Subject: Biology, Plant Sciences Keywords: 9-cis β-carotene; all-trans β-carotene; Dunaliella salina; red LED; blue LED; growth; light intensity; carotenoids; isomerisation
Online: 17 May 2019 (08:25:02 CEST)
Dunaliella salina is a rich source of 9-cis β-carotene, which has been identified as important in the treatment of retinal dystrophies and other diseases. We previously showed that chlorophyll absorption of red light photons in D. salina is coupled to oxygen reduction and phytoene desaturation and increases the pool size of β-carotene . Here we show for the first time that growth under red light also controls conversion of extant all-trans β-carotene to 9-cis β-carotene by β-carotene isomerases. Cells illuminated with red light from a light emitting diode (LED) during cultivation contained a higher 9-cis β-carotene content compared to cells illuminated with white or blue LED light. The 9-cis/all-trans β-carotene ratio in red light treated cultures reached >2.5:1 within 48 hours and was independent of light intensity. Illumination using red light filters that eliminated blue wavelength light also increased the 9-cis/all-trans β-carotene ratio. With norflurazon, a phytoene desaturase inhibitor which blocked downstream biosynthesis of β-carotene, extant all-trans β-carotene was converted to 9-cis β-carotene during growth with red light and the 9-cis/all-trans β-carotene ratio was ~2:1. With blue light under the same conditions, 9-cis β-carotene was likely destroyed at a greater rate than all-trans β-carotene (9-cis/all-trans ratio 0.5:1). Red light perception by the red light photoreceptor, phytochrome, may increase the pool size of anti-oxidant, specifically 9-cis β-carotene, both by upregulating phytoene synthase to increase the rate of biosynthesis of β-carotene and to reduce the rate of formation of reactive oxygen species (ROS), and by upregulating β-carotene isomerases to convert extant all-trans β-carotene to 9-cis β-carotene.
ARTICLE | doi:10.20944/preprints202212.0249.v1
Subject: Biology, Entomology Keywords: tan; Drosophila; Drosophila guttifera; CRM; cis-regulatory; evo-devo; yellow; transcription factor; cis-regulatory module; cis-regulatory element
Online: 14 December 2022 (06:48:07 CET)
How complex morphological patterns form is an intriguing question in developmental biology. However, the mechanisms that generate complex patterns remain largely unknown. Here we sought to identify the genetic mechanisms that regulate the tan (t) gene in a multi-spotted pigmentation pattern on the abdomen and wings of Drosophila guttifera. Previously, we showed that yellow (y) gene expression completely prefigures the abdominal  and wing  pigment patterns of this species. In the current study, we demonstrate that the t gene is co-expressed with the y gene in nearly identical patterns, both transcripts foreshadowing the adult abdominal and wing melanin spot patterns. We identified cis-regulatory modules (CRMs) of t, one of which drives reporter expression in six longitudinal rows of spots on the developing pupal abdomen, while the second CRM activates the reporter gene in a spotted wing pattern. Comparing the abdominal spot CRMs of y and t, we found a similar composition of putative transcription factor binding sites that are thought to regulate the complex expression patterns of both terminal pigmentation genes y and t. In contrast, the y and t wing spots appear to be regulated by distinct upstream factors. Our results suggest that the D. guttifera abdominal and wing melanin spot patterns have been established through the co-regulation of y and t, shedding light on how complex morphological traits may be regulated through the parallel coordination of downstream target genes.
REVIEW | doi:10.20944/preprints202002.0068.v1
Subject: Life Sciences, Genetics Keywords: cis-regulatory element; developmental modularity; evolutionary modularity; Heliconius
Online: 5 February 2020 (14:02:51 CET)
Developmental modularity has long been viewed as a hierarchical organization that facilitates evolution over macro-evolutionary time through modification or co-option of preexisting modules. More recently, developmental modularity has been proposed as a micro-evolutionary mechanism capable of driving rapid evolution of novel color pattern phenotypes between closely related taxa. In this scenario, swapping allelic variants of modular cis-regulatory elements (CREs) via recombination generates novel phenotypes by shuffling preexisting color pattern modules into new arrangements. Recent evidence from Drosophila and butterflies, however, provides a series of examples in which pleiotropic CREs function in multiple developmental contexts. The potential prevalence of pleiotropy in CRE function is a major barrier to the proposed evolutionary role of CRE modules and encourages us to reconsider the relative importance of modularity for microevolutionary change. Here we first review the case for the apparent frequent exchange of modular color pattern phenotypes as a mechanism facilitating diversification. We then contrast this with recent evidence of CRE pleiotropy and argue that exchange of CRE modules should not be the default assumption, even when phenotypes look modular. Finally, we review experimental data on Heliconius butterfly wing patterns—which appear modular—and introduce the concept of evolutionary modularity as an alternative to developmental modularity. Evolutionary modularity reconciles the appearance of modularity in comparative genomic studies of Heliconius color patterns with experimental data supporting a non-modular architecture. We propose that evolutionary modularity provides a potentially important pathway for exchange of phenotypic elements between hybridizing taxa independent of the underlying developmental architecture.
ARTICLE | doi:10.20944/preprints201910.0330.v1
Online: 29 October 2019 (10:23:19 CET)
Accumulating evidence suggests that mast cells should play critical roles in disruption and maintenance of intestinal homeostasis, although it remains unknown how they affect local microenvironment. Interleukin-9 (IL-9) was found to play critical roles in intestinal mast cell accumulation induced in various pathological conditions, such as parasite infection and oral allergen-induced anaphylaxis. Newly recruited intestinal mast cells trigger inflammatory responses and damage epithelial integrity through release of a wide variety of mediators including mast cell proteases. We established a novel culture model (mucosal mast cell-like cultured mast cells, MMC-like MCs), in which murine IL-3-dependent bone marrow-derived cultured mast cells (BMMCs) were further cultured in the presence of stem cell factor and IL-9. In MMC-like MCs, drastic up-regulation of Mcpt1 and Mcpt2 was found. Although histamine storage and tryptase activity were significantly downregulated in the presence of SCF and IL-9, it was entirely reversed when mast cells were co-cultured with a murine fibroblastic cell line, Swiss 3T3. MMC-like MCs underwent degranulation upon IgE-mediated antigen stimulation, which was found to less sensitive to lower concentrations of IgE in comparison with BMMCs. This model might be useful for investigation of the spatiotemporal changes of newly recruited intestinal mast cells.
REVIEW | doi:10.20944/preprints201810.0714.v1
Subject: Biology, Other Keywords: ncRNA; cis-encoded ncRNA; trans-encoded ncRNA; riboswitch; CRISPR.
Online: 30 October 2018 (08:48:47 CET)
Genes encoding regulatory RNAs known as short RNAs (sRNAs) or non-coding sRNAs (ncRNAs), modulate physiological responses through different mechanisms, through RNA-RNA interaction or RNA-protein interaction. These molecules transcribed in trans and in cis relative to the target RNA. They are located between the coding regions of proteins, i.e., in the intergenic regions of the genome and show signals of promoters and termini sequences generally Rho-independent. The size of the ncRNAs genes ranges from ~ 50 to ~ 500 nucleotides and several transcripts are processed by RNase with smaller end products, which modulate physiological responses through different mechanisms, by RNA-RNA interaction or RNA-protein interactions and some interactions may be stabilized by the Hfq chaperone. The Riboswitches constitute another class of ncRNAs, located in the 5'UTR region of an mRNA that promote transcriptional regulation through their interaction with a linker molecule. Recently, in prokaryotes, CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) regions have described, which repeats of sequences of palindromic bases are. Each replicate consists of short segments of "spacer DNA" from exposures prior to a bacteriophage virus or exogenous plasmid. The CRISPR system consists of an immune system of resistance to exogenous molecules.
Subject: Life Sciences, Other Keywords: tomato; 7-epi-zingiberene; 9-hydroxy-zingiberene; 9-hydroxy-10,11-epoxy zingiberene; spectrophotometer; absorbance; introgression; breeding; wild relatives
Online: 29 September 2021 (16:24:30 CEST)
Tomato (Solanum lycopersicum), an important vegetable crop, is a host for numerous pests and pathogens. Consequently, tomato breeders are striving to improve pest resistance. Many acces-sions of the wild relative S. habrochaites display high resistance towards arthropod pests such as spider mites and whiteflies and the presence of the sesquiterpene hydrocarbon 7-epi zingiberene in its trichomes has been associated with arthropod resistance. Consequently, tomato breeders are attempting to introgress 7-epi zingiberene from wild to cultivated tomato, which requires the ability to quantify zingiberene. 7-Epi zingiberene has conjugated double bonds causing it to ab-sorb uv light. In fact, de Freitas, et al.  have claimed that measurement of absorbance at 270 nm of tomato leaflet washes can be used to quantify zingiberene. However, this claim has never been critically evaluated. We initially evaluated the use of uv absorbance to estimate zingiberene content of leaflet washes from an interspecific hybrid tomato BC4F2 generation that was segre-gating widely for presence and abundance of zingiberene. When absorbances at 270 nm were compared with zingiberene measured by gas chromatography the resulting relationship did not obey the Beer-Lambert law. Consequently, we examined in detail aspects of the uv-absorbance of zingiberenoids by: 1) obtaining uv absorbance spectra for three isolated zingiberenoids and de-termining the relationship between the abundance of each isolated compound and absorbance at single wavelengths; 2) obtaining uv absorbance spectra of leaflet washes of relevant wild acces-sions and parents; 3) obtaining average absorbance spectra for interspecific generations of tomato that were segregating for abundance of zingiberenoids and determining their λmax values in the 250-280 nm region; 4) evaluating by regression the relationship between absorbance at a single wavelength and the concentration of zingiberene and when present, its derivatives, as measured by gas chromatography in several interspecific hybrid generations; and 5) exploring the potential use of absorbances at multiple wavelengths to improve estimates of concentrations of zingi-berenoids. Results indicated that isolated zingiberenoids as well as leaflet washes of wild tomatoes that contain zingiberenoids have broad absorbance spectra in the uv region with a λmax of 264 nm. The relationship between abundance of isolated zingiberenoids and absorbance at a single wavelength of 264 nm did obey the Beer-Lambert Law. Average absorbance spectra for leaflet washes from BC3F5 generation plants sampled by two methods, as well as from a BC5F1 and a BC3F3 generation showed subtle shifts in the λmax away from 264 nm. Furthermore, the rela-tionship between absorbance at 264 nm and zingiberenoid content of these generations did not obey the Beer-Lambert Law in that in each case regression of absorbance on zingiberenoid content of the leaflet washes resulted in non-zero intercept estimates that varied considerably among generations and sampling methods. Use of multiple wavelengths for estimation zingiberenoids in these breeding generations was explored and inclusion of additional absorbances at one or two wavelengths identified by stepwise regression always improved estimates of zingiberenoid content from absorbance data. However, the identified wavelength(s) differed among generations. Taken together the results indicate that measurement of absorbance of tomato leaflet washes at a single wavelength is not a reliable quantitative estimate of zingiberenoids in the leaflet wash. These estimates can be improved by utilizing absorbance at multiple wavelengths, but the par-ticular wavelengths will likely vary among generations. Lastly, measurement of absorbance may be a useful tool in identifying those relatively rare individuals in a generation that is widely segregating for zingiberenoid content. However, even in this situation the determination of the actual zingiberene content e.g., for comparison with the donor parent, would need to be back-stopped by a valid quantitative method such as gas chromatography.
REVIEW | doi:10.20944/preprints202209.0339.v1
Subject: Medicine & Pharmacology, Ophthalmology Keywords: cis-prenyltransferase; DHDDS; dolichol; Nogo-B receptor; retinal degeneration; RP59
Online: 22 September 2022 (10:18:11 CEST)
Retinitis pigmentosa-59 (RP59) is a rare, recessive form of RP, caused by mutations in the gene encoding DHDDS (dehydrodolichyl diphosphate synthase). DHDDS forms a heterotetrameric complex with Nogo-B Receptor (NgBR; gene NUS1) to form a cis-prenyltransferase (CPT) enzyme complex, which is required for synthesis of dolichol, which in turn is required for protein N-glycosylation as well as other glycosylation reactions in eukaryotic cells. Herein, we review the published phenotypic characteristics of RP59 models extant, with an emphasis on their ocular phenotypes, based primarily upon knock-in of known RP59-associated DHDDS mutations as well as cell type- and tissue-specific knockout of DHDDS alleles in mice. We also briefly review findings in RP59 patients with retinal disease and other patients with DHDDS mutations causing epilepsy and other neurologic disease. We discuss these findings in the context of addressing “knowledge gaps” in our current understanding of the underlying pathobiology mechanism of RP59, as well as their potential utility for developing therapeutic interventions to block the onset, or to dampen the severity or progression, of RP59.
Subject: Life Sciences, Biochemistry Keywords: circular RNAs (circRNAs); biogenesis; trans-acting proteins; cis-regulatory elements
Online: 16 July 2021 (14:48:13 CEST)
Circular RNAs (circRNAs), which are a class of non-coding RNA with covalently closed loops, play important roles in epigenetics regulation of gene expression at both the transcriptional and post-transcriptional level. Accumulating evidence demonstrated that numerous circRNAs were abnormally expressed in tumors and their dysregulation was involved in the tumorigenesis and metastasis of cancer. Although the functional mechanisms of many circRNAs have been revealed, why circRNAs are dysregulated in cancer remains elusive. CircRNAs are generated by a “backsplicing” process, which is regulated by different cis-regulatory elements and trans-acting proteins. Therefore, how these cis- and trans-elements change during tumorigenesis and how they regulate the biogenesis of circRNAs in cancer are two questions that interest us. In this review, we summarized the pathways for the biogenesis of circRNAs; and then illustrated why circRNAs dysregulated in cancer by discussing the changes of cis-regulatory elements and trans-acting proteins that related to circRNA splicing and maturation in cancer.
ARTICLE | doi:10.20944/preprints202001.0048.v1
Subject: Biology, Horticulture Keywords: cis-regulatory element; data mining; NBS-LRR resistance genes; Zucchini
Online: 5 January 2020 (17:22:10 CET)
Although Cucurbita pepo is one of the most variable species of the plant kingdom, Zucchini morphotype has undergone intensive breeding that has led to a narrow genetic base making the crop vulnerable to pest and diseases. This vulnerability makes the knowledge of resistance genes of utmost importance. In this study, a data mining search of Zucchini summer squash genome database was conducted to identify and annotate members of the NBS-encoding gene family. In order to characterize the retrieved genes in detail, they have been studied in the bases of phylogenetic relationships, structural diversity, conserved protein motifs, gene duplications and promoter region analysis. Our study shows that the NBS-encoding gene family is relatively small in Zucchini (34 members, which are separated into non-TIR- and TIR-NBS-LRR subfamilies) with a significantly lower number of R-genes than in other species. Duplications have not played a major role in the expansion of this type of genes in C. pepo. Among the cis-regulatory elements presented in these sequences, six motifs are over-represented. These elements were reported to be involved in pathogens or plant stress induced responses. These results will contribute to the identification, isolation and characterization of candidate R-genes, thereby providing insight into NBS gene family evolution in the species.
Subject: Social Sciences, Economics Keywords: economic growth; CO2 emissions; cancer incidence; the CIS region; panel data estimation
Online: 12 January 2020 (16:33:48 CET)
It is widely discussed that growth of GDP has a vague impact on environmental pollution due to the emissions of carbon dioxide from consumed fossil fuels in production, transportation and power generation, and creation of required instruments to control environmental pollution as well. Due to the fact that environmental pollution can be a reason of mortality increase in a society, the main purpose of this study is to investigate the relationship between economic growth, fossil fuel consumption, mortality (from cardiovascular disease, cancer, diabetes and chronic respiratory disease) and environmental pollution using Generalized Method of Moments (GMM) estimation technique in the case of CIS member states over the period of 1993-2018. The major results revealed CO2 emissions in in the region of CIS have a positive effect on increase of mortality from cardiovascular disease, cancer, diabetes and chronic respiratory disease. In regards to fossil fuel consumption, the estimation proved that this variable affects mortality from cardiovascular disease, cancer, diabetes and chronic respiratory disease positively. In addition, we found effect of economic growth, population growth and inflation rate positively, while any improvement in human development index (HDI) has a negative effect on increase of mortality from cardiovascular disease, cancer, diabetes and chronic respiratory disease in the CIS region. It is recommended that the CIS member states carry out different policies to improve energy transition indicating movement from fossil fuel energy sources to renewable ones. Moreover, we recommend the CIS member states to enhance various policies for easy access to the electricity from green sources and increase of renewable supply through improved technologies, sustainable economic growth, and increase of using green source in daily social life.
REVIEW | doi:10.3390/sci1010005.v1
Subject: Keywords: carbocyanine dyes; isomerization; trans and cis isomers; <em>meso</em>-substituted cyanines
Online: 29 November 2018 (00:00:00 CET)
One of the important features of polymethine (cyanine) dyes is isomerization around one of C–C bonds of the polymethine chain. In this review, spectral properties of the isomers, photoisomerization and thermal back isomerization of carbocyanine dyes, mostly meso-substituted carbocyanine dyes, are considered. meso-Alkyl-substituted thiacarbocyanine dyes are present in polar solvents mainly as cis isomers and, hence, exhibit no photoisomerization, whereas in nonpolar solvents, in which the dyes are in the trans form, photoisomerization takes place. In contrast, the meso-substituted dyes 3,3′-dimethyl-9-phenylthiacarbocyanine and 3,3′-diethyl-9-(2-hydroxy-4-methoxyphenyl)thiacarbocyanine occur as trans isomers and exhibit photoisomerization in both polar and nonpolar solvents. The behavior of these dyes may be explained by the fact that the phenyl ring of the substituent in their molecules can be twisted at some angle, removing the substituent from the plane of the molecule and reducing its steric effect on the conformation of the trans isomer. In some cases, photoisomerization of cis isomers of meso-substituted carbocyanine dyes is also observed (for some meso-alkyl-substituted dyes complexed with DNA and chondroitin-4-sulfate; for 3,3′-diethyl-9-methoxythiacarbocyanine in moderate polarity solvents). The cycle photoisomerization–thermal back isomerization of cyanine dyes can be used in various systems of information storage and deserves further investigation using modern research methods.
ARTICLE | doi:10.20944/preprints201801.0085.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: microglia; cyanobacterium; Scytonema; lipopolysaccharide; cytokine; chemokine; superoxide; MMP-9; rat
Online: 10 January 2018 (08:52:56 CET)
Cosmopolitan Gram-negative cyanobacteria may affect human and animal health by contaminating terrestrial, marine and freshwater environments with toxins, such as lipopolysaccharide (LPS). The cyanobacterial genus Scytonema (S) produces several toxins, but to our knowledge the bioactivity of genus Scytonema LPS has not been investigated. We recently reported that cyanobacterium Oscillatoria sp. LPS elicited classical and alternative activation of rat microglia in vitro . Thus, we hypothesized that treatment of brain microglia in vitro with either cyanobacteria S. javanicum or S. ocellatum LPS might stimulate classical and alternative activation with concomitant release of superoxide anion (O2−), matrix metalloproteinase-9 (MMP-9) and cytokines and chemokines. Microglia were isolated from neonatal rats and treated in vitro with either S. javanicum LPS, S. ocellatum LPS, or E. coli LPS (positive control) in a concentration-dependent manner for 18 hours at 35.9 °C. We observed that treatment of microglia with either E. coli LPS, S. javanicum or S. ocellatum LPS generated statistically significant and concentration-dependent O2−, MMP-9 and pro-inflammatory cytokines IL-6 and TNF-α, pro-inflammatory chemokines MIP-2/CXCL-2, CINC-1/CXCL-1 and MIP-1α/CCL3, and the anti-inflammatory cytokine IL-10. Thus, our results provide experimental support for our working hypothesis because both S. javanicum and S. ocellatum LPS elicited classical and alternative activation of microglia and concomitant release of O2-, MMP-9 and cytokines and chemokines in a concentration-dependent manner. To our knowledge this is the first report on the toxicity of cyanobacteria S. javanicum and S. ocellatum LPS to microglia, an immune cell type involved in neuroinflammation and neurotoxicity in the central nervous system.
ARTICLE | doi:10.20944/preprints202105.0393.v1
Subject: Chemistry, Food Chemistry Keywords: cannabidiol (CBD); ∆9-tetrahydrocannabinol (∆9-THC); cannabinol (CBN); ∆8-tetrahydrocannabinol (∆8-THC); cannabinoids; CBD oil; nuclear magnetic resonance spectroscopy (NMR); PULCON methodology; 1H NMR; qNMR
Online: 17 May 2021 (16:56:15 CEST)
Toxicologically relevant levels of the psychoactive ∆9-tetrahydocannabinol (∆9-THC) as well as high levels of non-psychoactive cannabinoids potentially occur in CBD (cannabidiol) oils. For consumer protection in the fast-growing CBD oil market, facile and rapid quantitative methods to determine the cannabinoid content are crucial. However, the current standard method, i.e., liquid chromatography combined with tandem mass spectrometry (HPLC-MS/MS), requires a time-consuming multistep sample preparation. In this study, a quantitative nuclear magnetic resonance spectroscopy (qNMR) method for screening cannabinoids in CBD oils was developed. Contrary to the HPLC-MS/MS method, this qNMR features a facile sample preparation, i.e., only diluting the CBD oil in deuterochloroform. Pulse length-based concentration determination (PULCON) enables a direct quantification using an external standard. The signal intensities of the cannabinoids were enhanced during the NMR spectra acquisition by means of multiple suppression of the triglycerides which are a major component of the CBD oil matrix. The validation confirmed linearity for CBD, cannabinol (CBN), ∆9-THC and ∆8-THC in hemp seed oil with sufficient recoveries and precision for screening. Comparing the qNMR results to HPLC-MS/MS data for 46 commercial CBD oils verified the qNMR accuracy for ∆9-THC and CBD but with higher limits of detection. The developed qNMR method paves the way for increasing the sample throughput as a complementary screening before HPLC-MS/MS.
REVIEW | doi:10.20944/preprints202208.0418.v1
Subject: Medicine & Pharmacology, Oncology & Oncogenics Keywords: cannabidiol; Δ-9-tetrahydrocannabinol; cancer; nausea; vomiting; pain management; antitumor; marijuana
Online: 24 August 2022 (10:42:56 CEST)
Cannabis has been used as an herbal remedy for thousands of years and recent research indicates promising new uses in medicine. Researchers have been particularly interested in the potential uses of cannabinoids in treating cancer due their ability to regulate cancer-related cell cycle pathways, leading to many beneficial effects such as tumor growth prevention, cell cycle obstruction, and cell death. The aim of this review is to summarize current knowledge on mechanisms of cannabinoids and their role in treating chemotherapy-induced nausea and vomiting, relieving cancer-associated pain, and obstructing tumor cell growth.
ARTICLE | doi:10.20944/preprints202206.0020.v1
Subject: Earth Sciences, Environmental Sciences Keywords: Landsat-9 data; Qinghai-Tibet Plateau; Lake Waterbody; GEE; Algorithms comparison
Online: 1 June 2022 (13:14:56 CEST)
The monitoring of lake waterbody area in the Qinghai Tibet Plateau (QTP) is of great significance to deal with global climate change. As the latest generation of Landsat series satellites, Landsat-9 data not only have higher radiometric resolution, but also cooperate with other Landsat satellites to greatly improve the temporal resolution. It has great application potential in lake waterbody area monitoring. In order to explore the performance of different algorithms for extracting waterbody and lake waterbody area in Landsat-9 data under large-scale QTP regions, this study relies on Google Earth Engine (GEE) platform and selects 10 waterbody extraction algorithms as the basis to realize the quantitative evaluation of QTP lake waterbody area extraction results. The results show that the Random Forest (RF) algorithm performs best in all models. The overall accuracy of waterbody extraction is 95.84%, and the average error of lake waterbody area extraction is 1.505%. Among the traditional threshold segmentation waterbody extraction algorithms, the overall accuracy of the NDWI waterbody extraction method is 89.89%, and the average error of lake waterbody area extraction is 3.501%, which is the highest performance model in this kind of algorithms. This study proves that Landsat-9 data can effectively classify QTP waterbodies. With the development of cloud computing technologies such as Gee, more complex models such as RF can be selected to improve the extraction accuracy of water body and Lake area in large-scale research.
Subject: Medicine & Pharmacology, Allergology Keywords: microRNA; sevoflurane; desflurane; hypoxia inducible factor-1α; matrix metalloproteinase 9; glioma
Online: 23 March 2021 (09:14:01 CET)
Inhalational anesthetics was previously reported to suppress glioma cell malignancy, but underlying mechanisms remain unclear. The present study aims to investigate the effects of sevoflurane and desflurane on glioma cell malignancy changes via microRNA (miRNA) modulation. The cultured H4 cells were exposed to 3.6% sevoflurane or 10.3% desflurane for 2 hrs. The miR-138, -210 and -335 expression were determined with qRT-PCR. Cell proliferation and migration were assessed with wound healing assay, Ki67 staining and cell count kit 8 (CCK8) assay with/without miR-138/-210/-335 inhibitor transfections. The miRNA downstream proteins, hypoxia inducible factor-1α (HIF-1α) and matrix metalloproteinase 9 (MMP9), were also determined with immunofluorescent staining. Sevoflurane and desflurane exposure to glioma cells inhibited their proliferation and migration. Sevoflurane exposure increased miR-210 expression whereas desflurane exposure upregulated both miR-138 and miR-335 expressions. The administration of inhibitor of miR-138, -210 or -335 inhibited the suppressing effects of sevoflurane or desflurane on cell proliferation and migration, in line with the HIF-1α and MMP9 expression changes. These data indicated that inhalational anesthetics, sevoflurane and desflurane, inhibited glioma cell malignancy via miRNA upregulation and their downstream effectors, HIF-1α and MMP9, downregulation. The implication of the current study warrants further study.
ARTICLE | doi:10.20944/preprints201709.0157.v1
Subject: Chemistry, Organic Chemistry Keywords: rare earth metal complexes; 1,3-bis(oxazolinymethylidene)isoindoline ligand; polymerization; isoprene; cis-1,4-selectivity
Online: 29 September 2017 (14:50:39 CEST)
A series of novel chiral nonmetallocene pincer-type rare earth metal dialkyl complexes bearing the chiral monoanionic tridentate C2-symmetric 1,3-bis(oxazolinymethylidene)isoindoline (BOXMI) ligand (BOXMI)Ln(CH2SiMe3)2 1-3 (1, Ln = Sc, yield = 57%; 2, Ln = Lu, yield = 55%; 3, Ln = Y, yield = 62%) have been prepared in moderate yields via the acid-base reaction between the BOXMI ligand and rare earth metal tri(trimethylsilylmethyl) complexes. The X-ray diffractions show that both of the complexes 1 and 2 contain one Boxmi ligand and two trimethylsilylmethyl ligands, adopting a distorted-trigonal-bipyramidal configuration. In the presence of cocatalyst such as borate and AlR3, these complexes 1-3 exhibit high activities up to 6.8 × 104 (g of polymer)/(molLn h) and high cis-1,4-selectivities up to 97%) in the polymerization of isoprene in toluene, yielding the cis-1,4-polyisoprenes with high molecular weights (Mn up to 710000 g/mol) and bimodal molecular weight distributions (Mw/Mn = 2.0-4.5).
ARTICLE | doi:10.20944/preprints201810.0267.v1
Subject: Earth Sciences, Environmental Sciences Keywords: Mg/Ca; biominerliazation; nucleation site; Bacillus licheniformis DB1-9; carbonic anhydrase; ammonia
Online: 12 October 2018 (11:56:44 CEST)
Biomineralization has become a research hotspot and attracted widespread attention in the field of carbonate sedimentology. In this study, Bacillus licheniformis DB1-9 was used to induce the calcium carbonate precipitation at different magnesium calcium molar ratios in the laboratory to further explore the biomineralization mechanism. Phylogenetic tree shows that the bacteria belongs to Bacillus licheniformis species. The ammonia and carbonic anhydrase can be released by this bacteria, resulting in the pH increase, and the carbonic anhydrase can also promote the hydration reaction of carbon dioxide and subsequently produce the bicarbonate and carbonate ions to elevate the supersaturation of calcium carbonate in the liquid culture medium to facilitate the precipitation of carbonate minerals. The calcites have a shape of rhombohedron, dumbell, and elongation, and aragonite often appears in the form of mineral aggregates, besides that there are also the spherical and the fusiform minerals. FTIR result shows there are some organic functional groups, such as C-O-C and C=O, beside of the characteristic peaks of the calcite and the aragonite, indicating that microbial metabolism is closely related to the mineral formation. The superthin slices of the bacteria analyzed by HRTEM, SAED, EDS and STEM show that the surface and EPS can adsorb a large number of calcium ions and magnesium ions and EPS may act as the nucleation sites, what’s more, the intracellular nanometer-scale sphere areas show the amorphous structures, and the intracellular calcium ions and magnesium ions suggeste that they can be transported from the outside to inside the cell by diffusion along the concentration grade from high to low. This study may provide some references to further understand the biomineralization mechanism induced by microorganisms in the laboratory and the field, and also helps to explore the reason of the transition of calcite sea to aragonite sea in the geological history.
REVIEW | doi:10.20944/preprints202103.0500.v1
Subject: Chemistry, Analytical Chemistry Keywords: cyclolinopeptide A; cyclosporine A; immunosuppression; PGE2; edge-to-face; cis-peptide bond; homo amino acids
Online: 19 March 2021 (12:53:06 CET)
The consequences of manipulations in structure and amino acid composition of native cyclolinopeptide A (CLA) from linen seeds and its linear precursor on their biological activities and mechanisms of action are reviewed. The modifications included truncation of the peptide chain, replacement of amino acid residues with proteinogenic or non-proteinogenic ones, modifications of peptide bond, and others. The studies revealed changes in the immunosuppressive potency of these analogs investigated in a number of in vitro and in vivo experimental models, predominantly in rodents, as well as differences in their postulated mechanism of action. The modified peptides were compared with cyclosporine A and parent CLA. Some of the synthesized and investigated peptides show potential therapeutic usefulness.
ARTICLE | doi:10.20944/preprints202209.0181.v1
Subject: Social Sciences, Geography Keywords: geographical location; relief; climate; hydrographic; biological; comfort; grid index; 9 assessment; tourist route
Online: 13 September 2022 (13:39:08 CEST)
The article describes the methodology of the experimental analysis of operational and cost-effective assessment using geographic information system (GIS) technologies, as opposed to the assessment of the tourism potential of the nature of the Fergana Valley in Uzbekistan using long term and costly classical approaches. Based on the ArcGIS (10.8) grid index approach of 20 natural geographical indicators of the valley, such as geographical location, relief, climate, hydrographic and biological, the level of tourism comfort was determined and the location of 6 tourist-recreation zones were defined. The level of accuracy of the tourist-recreational zones all situated utilizing GIS technologies was confirmed by field-expedition approaches.
ARTICLE | doi:10.20944/preprints202103.0139.v1
Subject: Life Sciences, Other Keywords: ACTH(6-9); Neuroprotection; MPP+; H2O2; tert-butyl hydroperoxide; cyanide; melanocortins; oxidative stress
Online: 3 March 2021 (16:49:08 CET)
Stabilized melanocortin analog peptide ACTH(6-9)PGP (FRWGPGP) possess a wide range of neuroprotective activities. However, its mechanism of action remains poorly understood. In this paper, we studied the pro-proliferative and cytoprotective activity of the adrenocorticotropic hormone fragment 6-9 (FRWG) linked with the peptide Prolyl-Glycyl-Proline on the SH-SY5Y cells in the model of oxidative stress-related toxicity. The peptide dose-dependently protected cells from H2O2, tert-butyl hydroperoxide, and KCN. The mechanism of its action was the modu-lation of proliferation-related (NF-kB and Nrf-2) and antioxidant-related (HO-1, Nqo1, Gclc) genes and apoptosis decrease.
ARTICLE | doi:10.20944/preprints201710.0200.v1
Subject: Chemistry, Medicinal Chemistry Keywords: 4-Thiazolidinones; ORAC assay; Metalloproteinase-9; Docking study; Keratinocytes cultures; Nuclear factor -kB.
Online: 31 October 2017 (16:36:16 CET)
Nine 2-(1,2-benzothiazol-3-yl)-N-(4-oxo-2-phenyl-1,3-thiazolidin-3-yl) propanamides were designed and synthesized, combining benzisothiazole and 4-thiazolidinone in one frame. The aim of the study was to verify their effectiveness to contrast the inflammatory/oxidative process in which free oxygen and nitrite (ROS and RNS) radicals, advanced glycation products (AGEs), inflammatory cytokines and matrix metalloproteinases (MMPs) are involved. Docking studies of all the compounds were performed in order to explore their binding mode at the MMP-9 protein. An appreciable anti-inflammatory/wound healing effects of the tested compounds was highlighted. Derivative 23, bearing a 4-carboxyphenyl substituent at C2 of the 4-thiazolidinone ring, exhibited the highest activity, being able to inhibit MMP-9 at nanomolar level (IC50 = 40 nM).
ARTICLE | doi:10.20944/preprints201810.0185.v1
Subject: Biology, Animal Sciences & Zoology Keywords: long non-coding RNA; bovine mammary gland; linseed/safflower oil; lipid metabolism; fatty acid synthesis; cis-regulation
Online: 9 October 2018 (10:53:39 CEST)
This study aimed to characterize the long non-coding RNA (lncRNA) expression in the bovine mammary gland and to infer their functions in dietary response to 5% linseed oil (LSO) or 5% safflower oil (SFO). Twelve cows (six per treatment) in mid lactation were fed a control diet for 28 days followed by a treatment period (control diet supplemented with 5% LSO or 5% SFO) of 28 days. Mammary gland biopsies were collected from each animal on day-14 (D-14, control period), D+7 (early treatment period) and D+28 (late treatment period) and were subjected to RNA-Sequencing and subsequent bioinformatics analyses. Functional enrichment of lncRNA was performed via potential cis regulated target genes located within 50 Kb flanking regions of lncRNAs and having expression correlation of >0.7 with mRNAs. A total of 4955 lncRNAs (325 known and 4630 novel) were identified which potentially cis targeted 59 and 494 genes in LSO and SFO treatments, respectively. Enrichments of cis target genes of lncRNAs indicated potential roles of lncRNAs in immune function, nucleic acid metabolism and cell membrane organization processes as well as involvement in Notch, cAMP and TGF-β signaling pathways. Thirty-two and 21 lncRNAs were differentially expressed (DE) in LSO and SFO treatments, respectively. Six genes (KCNF1, STARD13, BCL6, NXPE2, HHIPL2 and MMD) were identified as potential cis target genes of six DE lncRNAs. In conclusion, this study indicated potential roles for lncRNAs in mammary gland immune functions and development and provided potential candidate genes and pathways via which lncRNAs can function in diet responses.
REVIEW | doi:10.20944/preprints202008.0102.v1
Subject: Mathematics & Computer Science, Probability And Statistics Keywords: epidemiology; disaster epidemiology; data matching; record linkage; probabilistic record linkage; interagency cooperation; 9/11 health
Online: 4 August 2020 (16:06:37 CEST)
Since its post-World War II inception, the science of record linkage has grown exponentially and is used across industrial, governmental, and academic agencies. The academic fields that rely on record linkage are diverse, ranging from history to public health to demography. In this paper, we introduce the different types of data linkage and give a historical context to their development. We then introduce the three types of underlying models for probabilistic record linkage: Fellegi-Sunter based methods, machine learning methods, and Bayesian methods. Practical considerations such as data standardization and privacy concerns are then discussed. Finally, recommendations are given for organizations developing or maintaining record linkage programs, with an emphasis on organizations measuring long-term complications of disasters such as 9/11.
ARTICLE | doi:10.20944/preprints201705.0013.v1
Subject: Materials Science, General Materials Science Keywords: Pb(Zn1/3Nb2/3) O3-9%PbTiO3; relaxor ferroelectric crystals; structure phase transition; electromechanical coupling factor
Online: 1 May 2017 (10:35:10 CEST)
Piezoelectric properties are of significant importance to medical ultrasound, actuators, sensor, and countless other device applications. The mechanism of piezoelectric properties can be deeply understood from structure evolutions. In this paper, we report a diagram of structure evolutions of the Pb(Zn1/3Nb2/3)0.91Ti0.09O3 (PZN-9PT) single crystal with excellent piezoelectric properties among the orthorhombic, tetragonal, and cubic phases with temperature increasing from room temperature to 220 C. Through fitting the temperature dependence XRD curves with Gauss and Lorenz functions, we obtained the evolutions of the content ratio of three kinds of phases (orthorhombic, tetragonal and cubic) and the lattice parameters of the PZN-9PT system with the changes of temperature. The XRD fitting results together with Raman and dielectric spectrums show that the phase transitions of PZN-9PT are a typical continuous evolution process, very similar to the phase transition of paraffin from solid to liquid. Additionally, resonance and anti-resonance spectrum show excellent piezoelectric properties of the crystals, which probably originate from the nano twin domains, as demonstrated by the TEM images. Of particular attention is that the thickness electromechanical coupling factor kt is up to 72%.
ARTICLE | doi:10.20944/preprints202111.0176.v1
Subject: Life Sciences, Microbiology Keywords: whole genome sequencing; antibiotic resistance; Salmonella Enteritidis; Salmonella Typhimurium; Salmonella Bovismorbificans; colistin resistance; mcr-1; mcr-9
Online: 9 November 2021 (13:46:05 CET)
Polymyxin resistance, determined by mcr genes located on plasmid DNA, currently pose a high epidemiological threat. Non-typhoid Salmonella (NTS) are one of the key pathogens causing diarrheal diseases. Here, we report the isolation and whole genome sequencing of multidrug colistin-resistant/susceptible isolates of non-typhoid Salmonella enterica serovars carries mcr genes. Non-typhoid strains of Salmonella enterica subsp. enterica were isolated during microbiological monitoring of the environment, food, and diarrheal disease patients between 2018 and 2020 in Russia (n=586). mcr-1 genes were detected using a previously developed qPCR assay and whole genome sequencing of mcr positive isolates was performed by both short-read (Illumina) and long-read (Oxford Nanopore) approaches. Three colistin-resistant isolates including two isolates of S. Enteritidis and one isolate of S. Bovismorbificans carried the mcr-1.1 gene located on IncX4 and IncI2 conjugative plasmids, respectively. The phenotypically colistin-susceptible isolate of S. Typhimurium carried a mcr-9 gene on plasmid IncHI2. In conclusion, we present the first three cases of mcr gene carrying NTS isolates detected in Russia with both outbreak and sporadic epidemiological background.
ARTICLE | doi:10.20944/preprints202106.0726.v1
Subject: Medicine & Pharmacology, Allergology Keywords: 9-tetrahydrocannabinol, intrauterine growth restriction, liver, metabolism, triglycerides, oxidative stress, mitochondria, miR-203a-3p, miR-29a/b/c
Online: 30 June 2021 (09:50:15 CEST)
Rates of gestational cannabis use have increased despite limited evidence for its safety in fetal life. Recent animal studies demonstrate that prenatal exposure to 9-tetrahydrocannabinol (9-THC, the psychoactive component of cannabis) promotes intrauterine growth restriction (IUGR), culminating in postnatal metabolic deficits. Given IUGR is associated with impaired hepatic function, we hypothesized that 9-THC offspring would exhibit hepatic dyslipidemia. Pregnant Wistar rat dams received daily injections of vehicular control or 3 mg/kg 9-THC i.p. from embryonic day (E) 6.5 through E22. Exposure to 9-THC decreased the liver to body weight ratio at birth, followed by catch-up growth by three weeks of age. At six months, 9-THC-exposed male offspring exhibited increased visceral adiposity and higher hepatic triglycerides. This was instigated by augmented expression of enzymes involved in triglyceride synthesis (ACC, SCD, FABP1, and DGAT2) at three weeks. Furthermore, the expression of hepatic DGAT1/DGAT2 was sustained at six months, concomitant with mitochondrial dysfunction (i.e., elevated p66shc) and oxidative stress. Interestingly, decreases in miR-203a-3p and miR-29a/b/c, both implicated in dyslipidemia, was also observed in these 9-THC-exposed offspring. Collectively, these findings indicate that prenatal 9-THC exposure results in long-term dyslipidemia associated with enhanced hepatic lipogenesis. This is attributed by mitochondrial dysfunction and epigenetic mechanisms.
REVIEW | doi:10.20944/preprints201809.0430.v1
Subject: Mathematics & Computer Science, Geometry & Topology Keywords: Spin(9); octonions; vector fields on spheres; Hopf fibration; locally conformally parallel; Clifford structure; Clifford system; symmetric spaces
Online: 21 September 2018 (06:07:27 CEST)
Starting from Thomas Friedrich’s work “Weak Spin(9) structures on 16-dimensional Riemannian manifolds”, we review several interactions between Spin(9) and geometries related to octonions. Several topics are discussed in this respect: explicit descriptions of the Spin(9) canonical 8-form and its analogies with quaternionic geometry, the role of Spin(9) both in the classical problems of vector fields on spheres and in the geometry of the octonionic Hopf fibration. Next, we deal with locally conformally parallel Spin(9) manifolds in the framework of intrinsic torsion. Finally, we discuss applications of Clifford systems and Clifford structures to Cayley-Rosenfeld planes and to three series of Grassmannians.
Subject: Medicine & Pharmacology, Other Keywords: adult 1; classification 2; consensus 3; goal 4; guideline 5; immune thrombocytopenia 6; indication 7; ITP 8; therapy 9
Online: 28 February 2020 (16:18:38 CET)
Despite the publication in 2009 of a paper on ‘terms and definitions of immune thrombocytopenia’, (ITP) some unresolved issues remain and are reflected by the disagreement in the treatment suggested for primary ITP in adults. Considering that these disagreements could be ascribed to non-shared goals, a ‘consensus’ to classify the different lines of treatment for primary ITP in adults according to their indications and goals was proposed in October 2018 to the XIX annual meeting of the Italian Gruppo di Studio delle Piastrine (GSP), a non-profit platelet study group of scientists and physicians. Having approved the project, 60 potential co-authors and experts in the world were invited to take part to a consensus through e-Delphy method and nine of the 12 who initially accepted the invitation completed the work. Agreement was reached on a classification of four lines of treatment for primary ITP in adults based on their indications and goals. The consensus obtained regarded also the criteria, ‘timing’ included, to consider practicable elective splenectomy in these patients. In our opinion, the classification of the lines of treatment for primary ITP in adults here proposed could facilitate the realization of better shared evidence-based guidelines for the treatment of the disease.
ARTICLE | doi:10.20944/preprints202204.0077.v1
Subject: Life Sciences, Biochemistry Keywords: Delta-9-tetrahydrocannabinol; cannabidiol; cannabinoids; NLRP3 inflammasome; STAT3; TYK2; cytokine storm; interleukins; TNF-α; macrophages; primary lung bronchial epithelial cells
Online: 8 April 2022 (08:51:26 CEST)
Cannabinoids, mainly cannabidiol (CBD) and Δ9-tetrahydrocannabinol (THC), are the most studied group of compounds obtained from Cannabis sativa because of their several pharmaceutical properties. Current evidence suggests a crucial role of cannabinoids as potent anti-inflammatory agents for the treatment of chronic inflammatory diseases; however, the mechanisms remain largely unclear. Cytokine storm, a dysregulated severe inflammatory response by our immune system, is involved in the pathogenesis of numerous chronic inflammatory disorders, including coronavirus disease 2019 (COVID-19), which results in the accumulation of pro-inflammatory cytokines. Therefore, we hypothesized that CBD and THC reduce the levels of pro-inflammatory cytokines by inhibiting key inflammatory signalling pathways. The nucleotide-binding and oligomerization domain (NOD)-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome signalling has been implicated in a variety of chronic inflammatory diseases, which results in the release of pyroptotic cytokines, interleukin-1β (IL-1β) and IL-18. Likewise, the activation of the signal transducer and activator of transcription-3 (STAT3) causes increased expression of pro-inflammatory cytokines. We studied the effects of CBD and THC on lipopolysaccharide (LPS)-induced inflammatory response in human THP-1 macrophages and primary human bronchial epithelial cells (HBECs). Our results revealed that CBD and, for the first time, THC, significantly inhibited NLRP3 inflammasome activation following LPS + ATP stimulation, leading to a reduction in the levels of IL-1β in THP-1 macrophages and HBECs. CBD attenuated the phosphorylation of nuclear factor-κB (NF-κB) and both cannabinoids inhibited the generation of oxidative stress post-LPS. Our multiplex ELISA data revealed that CBD and THC significantly diminished the levels of IL-6, IL-8, and tumor necrosis factor-α (TNF-α) after LPS treatment in THP-1 macrophages and HBECs. In addition, the phosphorylation of STAT3 was significantly downregulated by CBD and THC in THP-1 macrophages and HBECs, which was in turn, attributed to the reduced phosphorylation of tyrosine kinase-2 (TYK2) by CBD and THC after LPS stimulation in these cells. Overall, CBD and THC were found to be effective in alleviating the LPS-induced cytokine storm in human macrophages and primary HBECs, at least via modulation of NLRP3 inflammasome and STAT3 signalling pathways. The encouraging results from this study warrant further investigation of these cannabinoids in vivo.
Subject: Life Sciences, Immunology Keywords: NK cell biology; NK cell subsets; NK activating receptors; cell adhesion molecules; granule polarization; cytotoxicity assay; cis interactions; trogocytosis; NK cell degranulation; NK-Based Immunotherapies
Online: 14 February 2020 (03:13:05 CET)
NK population is characterized by distinct NK cell subsets which respond differently to the various activating stimuli. For this reason, the determination of the optimal cytotoxic activation of the different NK subsets can be a crucial aspect to be exploited to counter cancer cells in oncologic patients. To evaluate how the triggering of different combination of activating receptors can affect the cytotoxic responses of different NK cell subsets, we developed a microbead-based degranulation assay. By using this new assay, we were able to detect CD107a+ degranulating NK cells even within the less cytotoxic subsets (i.e. resting CD56bright and unlicensed CD56dim NK cells), thus demonstrating its high sensitivity. Interestingly, signals delivered by the co-engagement of NKp46 with 2B4, but not with CD2 or DNAM-1, strongly cooperate to enhance degranulation on both licensed and unlicensed CD56dim NK cells. Of note, 2B4 is known to bind CD48 hematopoietic antigen, therefore this observation may provide the rationale why CD56dim subset expansion correlates with successful hematopoietic stem cell transplantation mediated by alloreactive NK cells against host T, DC and leukemic cells, while sparing host non-hematopoietic tissues and graft versus host disease. The assay further confirms that activation of LFA-1 on NK cells leads to their granule polarization, even if, in some cases, this also takes to an inhibition of NK degranulation, suggesting that LFA-1 engagement by ICAMs on target cells may differently affect NK cell response. Finally, we observed that NK cells undergo a time-dependent spontaneous (cytokine-independent) activation after blood withdrawal, an aspect that may strongly bias the evaluation of the resting NK cell response. Altogether our data may pave the way to develop new NK activation and expansion strategies that target the highly cytotoxic CD56dim NK cells and can be feasible and useful for cancer and viral infection treatment.
Subject: Life Sciences, Biophysics Keywords: consciousness 1; subjective experience 2; will 3; agency 4; self 5; psychopathology 6; treatment 7; transcranial near infrared light 8; biophotomodulation 9
Online: 25 May 2021 (08:44:47 CEST)
In this paper I will address Dr. Sonne’s questions about will, agency, choice, consciousness, relevant brain regions, impacts of disorders and their therapeutics, and I will do this by referring to my theory, Dual-brain Psychology, which posits that within most of us there exist two mental agencies with different experiences, wills, choices, and behaviors. Each of these agencies is associated as a trait with one brain hemisphere (either left or right) and its composite regions. One of these agencies is more adversely affected by past traumas and is more immature and more symptomatic while the other is more mature and healthier. The theory has extensive experimental support through 17 peer-reviewed publications with clinical and non-clinical research. I will discuss how this theory relates to the questions that Dr. Sonne presented and will discuss also my published theory on the physical nature of subjective experience and its relation to the brain and how that theory interacts with DBP, and how the 2 theories relate to subjective experience, will, behavior, psychopathology and its treatment.
ARTICLE | doi:10.20944/preprints201809.0272.v1
Subject: Life Sciences, Molecular Biology Keywords: Keywords: 1; genome 2; epigenetics 3; neurodevelopmental disorders; 4; chromosome anomalies; 5; retrotransposon; 6; chromosome rearrangement; 7; neurologic disease; 8; birth defects; 9; development 10; infection
Online: 15 September 2018 (18:07:03 CEST)
Abstract: The purpose of this study was to understand the role of infection in the origin of chromosomal anomalies linked to neurodevelopmental disorders. In patients with neurodevelopmental disorders, DNA’s from viruses and bacteria including known teratogens were tested against chromosome anomalies known to cause the disorders. Results support a theory that parental infections disrupt elaborate multi-system gene coordination needed for neurodevelopment. Genes essential for neurons, lymphatic drainage, immunity, circulation, angiogenesis, barriers, structure, and chromatin activity were all found close together in polyfunctional clusters that were deleted in neurodevelopmental disorders. These deletions account for immune, circulatory, and structural deficits that accompany neurologic deficits. In deleted clusters, specific and repetitive human DNA matched infections and passed rigorous artifact tests. In some patients, epigenetic driver mutations were found and may be functionally equivalent to deleting a cluster or changing topologic chromatin interactions because they change access to large chromosome segments. In three families, deleted DNA sequences were associated with intellectual deficits and were not included in any database of genomic variants. These sequences were thousands of bp and unequivocally matched foreign DNAs. Analogous homologies were also found in chromosome anomalies of a recurrent neurodevelopmental disorder. Viral and bacterial DNAs that match repetitive or specific human DNA segments are thus proposed to interfere with highly active break repair during meiosis, and sometimes delete polyfunctional clusters, and disable epigenetic drivers. Mis-repaired gametes produce zygotes containing rare chromosome anomalies which cause neurologic disorders and accompanying non-neurologic signs. Neurodevelopmental disorders may be examples of assault on the human genome by foreign DNA with some infections more likely tolerated because they resemble human DNA segments. Further tests of this model await new technology.
ARTICLE | doi:10.20944/preprints201901.0294.v1
Subject: Mathematics & Computer Science, Analysis Keywords: : Data preprocessing 1; data validation 2; recommendation engine 3; E-commerce 4; Click-through rate 5; Buy-through rate 6; online customer behavior 7; non-parametric outlier removal 8; personalization 9
Online: 29 January 2019 (09:49:55 CET)
E-commerce businesses employ recommender models to assist in identifying a personalized set of products for each visitor. To accurately assess the recommendations’ influence on customer clicks and buys, three target areas—customer behavior, data collection, user-interface —will be explored for possible sources of erroneous data. Varied customer behavior misrepresents the recommendations’ true influence on a customer due to the presence of B2B interactions and outlier customers. Non-parametric statistical procedures for outlier removal are delineated and other strategies are investigated to account for the effect of a large percentage of new customers or high bounce rates. Subsequently, in data collection we identify probable misleading interactions in the raw data, propose a robust method of tracking unique visitors, and accurately attributing the buy influence for combo products. Lastly, user-interface issues discuss the possible problems caused due to the recommendation widget’s positioning on the e-commerce website and the stringent conditions that should be imposed when utilizing data from the product listing page. This collective methodology results in an exact and valid estimation of the customer’s interactions influenced by the recommendation model in the context of standard industry metrics such as Click-through rates, Buy-through rates, and Conversion revenue.
BRIEF REPORT | doi:10.20944/preprints202003.0338.v3
Subject: Medicine & Pharmacology, Pathology & Pathobiology Keywords: Severe Acute Respiratory Syndrome Coronavirus-2; (soluble) ACE2; eosinophil; asthma; IL-10; Lung fibrosis; hypercapnic acidosis; hypoxia; infarction; hypertension; cardiac dysfunction; respiratory distress; coagulopathy; Angiotensin; renin; Ang (1-7); Ang (1-9); Mas receptor; AT2 receptor
Online: 6 May 2020 (04:40:25 CEST)
The article describes the rational for inhibition of the angiotensin-converting enzyme 2 (ACE2) pathways as specific targets in patients infected by SARS-CoV-2 in order to prevent the establishment of positive feedback loops triggered by COVID-19 in some predisposed subjects. Making use of a large quantity of published reports in which human/rodent ACE2 pathway inhibitors were administered in vivo, it is hypothesized a possible therapeutic pharmacological intervention through an inhibition strategy of the zinc metalloprotease ACE2 and its downstream pathway for SARS-CoV-2 patients. Of even more interest, metal (zinc) chelators and renin inhibitors (both FDA approved drugs) may also work alone or in combination in inhibiting the positive feedback loops, initially triggered by COVID-19 and subsequently sustained by hypoxia independently on viral trigger, when both arms of renin-angiotensin system (ACE2 and ACE) are upregulated, leading to critical, advanced and untreatable stages of the disease.