ARTICLE | doi:10.20944/preprints201801.0142.v2
Subject: Environmental And Earth Sciences, Waste Management And Disposal Keywords: ater-borne; iodine excess; impairement; control and prevention
Online: 8 February 2018 (15:21:11 CET)
Since the water-borne iodine excessive goiter was firstly found and reported in 19 in Hebei Province, it was confirmed successively. The national water-borne investigation carried out in 2005 demarcated the water-borne iodine excess areas and water-borne iodine excess endemial areas. The high iodine water well was found In 129 counties of 11 provinces, about 30.98 million people of threatened population lived in water-borne iodine excess areas and water borne iodine excess endemial areas. In these areas, the measures of prevention and control was effectively implemented. In 2016, the new standard of iodine excess area was issued, the iodine excess areas redrawed, and in these areas, non-iodized salt should be supplied and the drinking water should be gradually improved of water, and to control the damage of water-borne iodine excess at an early date
SHORT NOTE | doi:10.20944/preprints202108.0475.v1
Subject: Biology And Life Sciences, Food Science And Technology Keywords: Iodine; Iodine types; Iodine radioisotope; Iodine 129; Iodine toxicity; iodine intake; Iodine content in Canadian food.
Online: 24 August 2021 (14:40:05 CEST)
When you type” Iodine” in google scholar, you will end up with 2,200,000 articles that are titled with anything regarding iodine, except “what is it”. Here in this short note review, a summary of iodine that includes its origin, structure, types, sources, uses, concentration, toxicity, and iodine intake and how to measure it, was collected and infused in a nutshell.
ARTICLE | doi:10.20944/preprints202007.0473.v1
Subject: Biology And Life Sciences, Food Science And Technology Keywords: Pregnancy; Iodine; Dietary habits; Iodine supplement, Urinary iodine concentration
Online: 21 July 2020 (03:42:20 CEST)
Background: The nutritional status of women during pregnancy can have a considerable effect on maternal and fetal health, and on perinatal outcome. The aim was to assess the changes occurring in dietary iodine intake, KI supplementation, and smoking habit, and the impact of these changes on the urinary iodine concentration (UIC) during pregnancy in a population of women in Catalonia (Spain). Methods: Between 2009-2011 an observational study including a cohort of women whose pregnancy was monitored in the publically-funded health system in a central region of Catalonia. Women received individual educational counseling imparted, a dietary questionnaire was completed, and a urine sample collected for iodine determination at each trimester visit. Results: 633 (67.9%) women answered the questionnaire at all 3 visits. The percentage of women with a desirable UIC (≥150μg/L) increased from the first to the second trimester and remained stable in the third (p<0.001). Analysis of the relationship between UIC≥150 μg/L and the women’s dietary habits showed that the percentage with UIC≥150 μg/L increased with greater consumption of milk, fresh vegetables, and fruit in the first trimester, and the same was true for iodized salt use in all three trimesters and iodine supplementation in all three. Conclusion: During pregnancy increased intake of milk, iodized salt, and iodine supplements was associated with an increase in the UIC.
REVIEW | doi:10.20944/preprints202006.0345.v1
Subject: Medicine And Pharmacology, Obstetrics And Gynaecology Keywords: congenital hypothyroidism; transient; iodine deficiency; iodine excess; pregnancy; supplementation
Online: 28 June 2020 (19:51:04 CEST)
The iodine intake in a pregnant woman has been closely correlated with development of transient congenital hypothyroidism which leads to decline in neurocognitive abilities of the child later in life as the effects are very subtle at birth. Both low and excess ingestion of iodine has been found to contribute to this cause, although iodine deficiency is more commonly observed in women of underdeveloped nations. It poses risks not only to the foetus but also to the mother leading to obstetric complications such as still birth and spontaneous abortions. It can be prevented using WHO recommended daily iodine supplementation in deficient regions or decreasing the excess load in groups exposed to high iodine. Programmes designed to screen the new-born at birth can also help in improving the quality of life of the child. The deficient iodine condition is managed by administration of levothyroxine in dosage range of 10-15 mcg/kg/day. Generally, the prognosis of infants starting treatment early in life have a better neurocognitive outcome as compared to the treated infants late age at a later age. Avoidance of agents causing iodine exposure has resulted in decrease in the abnormal thyroid function levels.
ARTICLE | doi:10.20944/preprints202308.0639.v1
Subject: Medicine And Pharmacology, Endocrinology And Metabolism Keywords: iodine; pancreatitis; hypothyroidism; rabbits
Online: 8 August 2023 (08:37:22 CEST)
Pancreatic alterations like inflammation and insulin resistance accompany hypothyroidism. Molecular iodine (I2) exerts antioxidant and differentiation actions in several tissues, and the pancreas is an iodine-uptake tissue. We analyzed the effect of two oral I2 doses on pancreatic disorders in a model of hypothyroidism for 30 days. Adult female rabbits were divided into the following groups: control, moderate oral dose of I2 (0.2 mg/kg, M-I2), high oral dose of I2 (2.0 mg/kg, H-I2), oral dose of methimazole (MMI; 10 mg/kg), MMI+M-I2, and MMI+H-I2. Moderate or high I2 supplementation did not modify circulating metabolites or pancreatic morphology. The MMI group showed circulating reductions of thyroxine (T4) and triiodo-thyronine (T3), moderate glucose increments, and significant increases in cholesterol and low-density lipoproteins. Acinar fibrosis, high insulin content, lipoperoxidation, and over-expression of GLUT4 were observed in the pancreas of this group. M-I2 supplementation normalized the T4 and cholesterol, but T3 remained low. Pancreatic alterations were prevented, nuclear factor erythroid-2-related factor-2 (Nrf2), antioxidant enzymes, and peroxisome proliferator-activated receptor gamma (PPARG) maintained their basal values. In MMI+H-I2, hypothyroidism was avoided, but pancreatic alterations and low PPARG expression remained. In conclusion, M-I2 supplementation reestablishes thyronine synthesis and diminishes pancreatic alterations, possibly related to Nrf2 and PPARG activation.
ARTICLE | doi:10.20944/preprints202109.0170.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: molecular iodine; immune response; breast cancer
Online: 9 September 2021 (10:45:34 CEST)
Molecular iodine (I2) induces apoptotic, antiangiogenic, and antiproliferative effects in breast cancer cells. Little is known about its effects on the tumor immune microenvironment. We studied the effect of oral (5 mg/day) I2 supplementation alone (I2) or together with conventional chemotherapy (Cht+I2) on the im-mune component of breast cancer tumors from a previously published pilot study conducted in Mexico. RNA-seq, I2 and Cht+I2 samples showed significant increases in expression of Th1 and Th17 pathways. Tumor immune composition determined by deconvolution analysis revealed significant increases in M0 macrophages and B lymphocytes in both I2 groups. Real-time RT-PCR showed that I2 tumors overexpress T-BET (p = 0.019) and interferon-gamma (IFNγ; p = 0.020) and silence tumor growth factor-beta (TGFβ; p = 0.049); whereas in Cht+I2 tumors, GATA3 is silenced (p = 0.014). Preliminary methylation analysis shows that I2 activates IFNγ gene promoter (by increasing its unmethylated form) and silences TGFβ in Cht+I2. In conclusion, our data showed that I2 supplements induce the activation of the immune response and that when combined with Cht, the Th1 pathways are stimulated. The molecular mechanisms involved in these responses are being analyzed, but preliminary data suggest that methylation/demethylation mechanisms could also participate.
REVIEW | doi:10.20944/preprints202308.1380.v1
Subject: Chemistry And Materials Science, Polymers And Plastics Keywords: amylose; iodine; iodide; starch; UV-vis; DFT
Online: 21 August 2023 (03:08:53 CEST)
The nature of the blue color in the iodine-starch reaction (or, in most cases, iodine-iodide-starch reaction, i.e. as I2 as well as I- are typically present) has for decades elicited debate. The intensity of the color suggests a clear charge-transfer nature of the band at ~600 nm, and there is consensus regarding the fact that the hydrophobic interior of the amylose helix is the location where iodine binds. Three types of possible sources of charge transfer have been proposed: (1) chains of neutral I2 molecules, (2) chains of poly-iodine anions (complicated by the complex speciation of the I2 - I- mixture), or (3) mixtures of I2 molecules and iodide or polyiodide anions. An extended literature review of the topic is provided here. According to the most recent data, the best candidate for the “blue complex” is a I2-I5-I2 unit – expected to occur in repetitive manner inside the amylose helix.
ARTICLE | doi:10.20944/preprints202110.0343.v1
Subject: Biology And Life Sciences, Food Science And Technology Keywords: iodine nutritional status; BRAFV600E; papillary thyroid cancer
Online: 25 October 2021 (10:57:18 CEST)
Papillary thyroid carcinoma (PTC) accounts for approximately 85%-90% of all thyroid cancers. BRAFV600E mutation is a highly specific target for papillary thyroid carcinoma (PTC) and may have a reciprocal causative relationship with iodide-metabolizing genes. Here, we performed a review of studies published in the past 10 years to determine the relationship between iodine intake and BRAFV600E mutation in patients with PTC. We searched the MEDLINE, PubMed, and EMBASE databases for studies published from 2009 to 2019; seven partially matched the selection criteria and were suitable for review, and five passed all selection criteria. We divided the patients into three groups by iodine intake: low (urinary iodine concentration [UIC] <100 μg/L), adequate (UIC 100–200 μg/L), and high iodine intake groups (UIC ≥200 μg/L). Between-group analysis revealed no significant differences in the odds ratio of the prevalence of BRAFV600E mutation between the high and adequate/low iodine intake groups and between the adequate and low iodine intake groups. To further analyzed the results of studies, they exhibited U-shaped curves in the relation of deficient and excessive dietary iodine intake in BRAFV600E mutation. The results might suggest that iodine intake slightly influences the prevalence of BRAFV600E mutation in patients with PTC despite the heterogeneity of studies. Further research should explore potential mechanisms underlying the associations between iodine intake and BRAF mutation in PTC. The systematic review was registered in PROSPERO (CRD42021279462).
ARTICLE | doi:10.20944/preprints202002.0419.v1
Subject: Medicine And Pharmacology, Medicine And Pharmacology Keywords: Biofilm; Silver Gel; Betadine; Providone-Iodine; Antimicrobial
Online: 28 February 2020 (11:45:13 CET)
Betadine (Providone-Iodine) solution is a topically applied antiseptic, which has been used for wound care and surgery for decades for the prevention and treatment of skin and wound infections. However, several studies have documented the ineffectiveness of Betadine solution. Other topical antimicrobial dressings, including those that contain silver, have been used in the management of infected wounds. The present study was undertaken to determine if the combination of 5% Betadine solutions and silver colloidal gel (Ag-gel), is more effective than the individual materials in inhibiting the growth of both Gram negative and Gram positive bacteria. These determinations were carried out by both the colony forming unit (CFU) assay, and confocal laser scanning microscopy (CLSM). Ag-gel showed complete inhibition on all the bacteria, except Klebsiella pneumoniae CI strain while 5% Betadine concentrations did not completely kill any of the tested bacteria. However, K. pneumoniae was completely eliminated in the presence of the combination of 5% Betadine solution plus Ag-gel. Confocal laser microscopy confirmed the CFU results. Thus this study demonstrated that while the individual treatments are not effective in killing all the bacteria tested, the combination of 5% Betadine solution and Ag-gel completely kill all bacteria tested, including K. penumoniae CI.
ARTICLE | doi:10.20944/preprints201802.0015.v1
Subject: Medicine And Pharmacology, Dietetics And Nutrition Keywords: iodine; pregnancy; qualitative research; awareness; perceptions; nutrition
Online: 2 February 2018 (07:29:44 CET)
Iodine is essential for thyroid hormones synthesis and normal neurodevelopment; however, 60% of pregnant women do not meet the WHO recommended intake. Using a qualitative design, we explored perceptions, awareness and experiences of pregnancy nutrition, focusing on iodine. Women in the perinatal period (n=48) were interviewed and filled in a food frequency questionnaire for iodine. Almost all participants achieved the recommended 150 μg/day intake for non-pregnant adults (99%), but only 81% met the increased demands of pregnancy (250 μg/day). Most were unaware of the importance, sources and recommendations of iodine intake. Attitudes to dairy products consumption were positive (e.g. helps with heartburn; easy to increase). Increased fish consumption was considered less achievable, with barriers around taste, smell, heartburn and morning sickness. Community midwives were the main recognised provider of dietary advice. The dietary advice received focused most often on multivitamin supplements rather than food sources. Analysis highlighted a clear theme of commitment to change behaviour, motivated by pregnancy, with desired focus on user-friendly documentation and continued involvement of the health services. The study highlights the importance of redirecting advice on dietary requirements in pregnancy and offers practical suggestions from women in the perinatal period as the main stakeholder group.
ARTICLE | doi:10.20944/preprints201910.0328.v1
Subject: Biology And Life Sciences, Food Science And Technology Keywords: Republic of Moldova; salt; sodium; potassium; iodine; population
Online: 29 October 2019 (10:15:58 CET)
In the Republic of Moldova, nearly 90% of all deaths are due to noncommunicable diseases (NCDs), tha majority of which (58%) are caused by cardiovascular disease (CVD). Excess salt (sodium) and inadequate potassium intakes are associated with high CVD. Moreover, salt iodisation is the preferred policy to prevent iodine deficiency and associated disorders. However, there is no survey that has directly measured sodium, potassium and iodine consumption in adults in the Republic of Moldova. The aim is to estimate population sodium, potassium and iodine intakes and explore knowledge, attitudes and behaviour (KAB) towards the use of salt, amongst the adult population in the Republic of Moldova. Proportional random samples of adults were obtained from 28 of the 37 Districts and Municipalities and one Administrative Territorial Unit of Moldova. Participants attended a screening including demographic, anthropometric and physical measurements. Dietary sodium, potassium and iodine intakes were assessed by 24h urinary sodium (UNa), potassium (UK) and iodine (UI) excretions. Creatinine was measured. KAB was collected by questionnaire. Eight hundred and fifty-eight participants (326 men and 532 women, 18–69 years) were included in the analysis (response rate 66%). Mean age was 48.5 yrs (SD 13.8). Mean UNa was 172.7 (79.3) mmoL/day, equivalent to 10.8 g of salt/day and potassium excretion 72.7 (31.5) mmoL/day, equivalent to 3.26 g/day. Men ate more sodium and potassium than women. Only 11.3% of the sample had a salt intake below the World Health Organization (WHO) recommended target of 5 g/day and approximately 39% met WHO targets for potassium excretion (>90 mmoL/day). Whilst 81.7% declared limiting their consumption of processed food and over 70% declared not adding salt at the table, only 8.8% looked at sodium content of food, 31% still added salt when cooking and less than 1% took other measures to control salt consumption. Measures of awareness were significantly more common in urban compared to rural areas. Mean urinary iodine was 225 (SD: 152; median 196) mcg/24h, with no difference between sexes. According to WHO criteria, 41.0% had adequate iodine intake, 28.6% had intake below requirements and 17.8% and 12.6% had above requirement or excessive levels, respectively. Iodine content of salt table was 21.0 (SD: 18.6) mg/kg, with no difference between men and women. However, the content was lower in rural than urban areas (16.7 [SD: 18.6] vs 28.1 [SD: 16.5] mg/kg, p<0.001). There were weak or no correlations between urinary sodium and iodine excretions, and between urinary iodine excretion and iodine concentration in the table salt used in the participants’ households, indicating that in most cases participants were not using iodised salt as their main source of salt, more so in rural areas. In the Republic of Moldova, salt consumption is unequivocally high, potassium consumption is lower than recommended, both in men and in women, whilst iodine intake is still inadequate in 1 in 3 people, although severe iodine deficiency is rare. Salt consumed is often not iodised, with less iodised salt being used in rural areas.
ARTICLE | doi:10.20944/preprints201707.0056.v1
Subject: Medicine And Pharmacology, Dietetics And Nutrition Keywords: Iodine; processed foods; universal salt iodization; case studies
Online: 19 July 2017 (23:41:44 CEST)
The current performance indicator for universal salt iodization (USI) is the percent of households using adequately iodized salt. However, the proportion of dietary salt from household salt is decreasing with the increase in consumption of processed foods and condiments globally. This paper reports on case studies supported by the GAIN-UNICEF USI Partnership Project to investigate processed food industry use of adequately iodized salt in contrasting national contexts. Studies were conducted in Egypt, Indonesia, the Philippines, the Russian Federation, and Ukraine. In all cases, the potential iodine intake from iodized salt in selected food products was modelled according to the formula: Quantity of salt per unit of food product x minimum regulated iodine level of salt at production x average daily per capita consumption of the product. The percent of adult recommended nutrient intake for iodine potentially provided by the average daily intake of bread and frequently consumed foods and condiments was from 10% to 80% at the individual product level. The potential contribution to iodine intake from the use of iodized salt in the processed food industry is of growing significance. National USI strategies should encourage co-operative industry engagement and include regulatory monitoring of iodized salt use in the food industry in order to achieve optimal population iodine status.
ARTICLE | doi:10.20944/preprints201907.0152.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: molecular iodine; breast cancer; chemoresistance; immune response; transcriptomic analysis
Online: 11 July 2019 (05:49:35 CEST)
This study analyzes oral supplement of molecular iodine (I2) alone and in combination with the neoadjuvant therapy 5-fluorouracil/epirubicin/cyclophosphamide or taxotere/epirubicin (FEC/TE) in women with Early (stage II) and Advanced (stage III) breast cancer. In the Early group, 30 women were treated with I2 (5 mg/day) or placebo (colored water) for 7–35 days before surgery. For the Advanced group, 30 patients received I2 or placebo along with FEC/TE treatment. After surgery, all patients received FEC/TE + I2 for 170 days. I2 supplementation showed a significant attenuation of the side effects and absence of tumor chemoresistance. Control, I2, FEC/TE, and FEC/TE+I2 groups exhibit response rate of 0, 33%, 73%, and 100%, respectively, and a pathologic complete response of 18%, and 36% in the last two groups. Five-year disease-free survival rate was significantly higher in patients with I2 supplement before and after surgery compared to those receiving the supplement only after surgery (82% vs. 46%). I2-treated tumors exhibit less invasive potential, and significant increases in apoptosis, estrogen receptor expression, and immune cell infiltration. Transcriptomic analysis indicated activation of the antitumoral immune response. The results led us to register a phase III clinical trial analyzing chemotherapy + I2 treatment for advanced breast cancer.
ARTICLE | doi:10.20944/preprints202109.0088.v1
Subject: Environmental And Earth Sciences, Environmental Science Keywords: Iodine; leaching; HYDRUS 1D model; Simulation; Organic and inorganic amendments
Online: 6 September 2021 (12:07:01 CEST)
This study investigated the ability of a HYDRUS 1D model for predicting the vertical distribution of potassium iodine (200 ppm) in soil columns after amendment with five different common remediation materials (gypsum, lime, fly ash, charcoal and sawdust) at a rate of 2.5% (w/w), relative to an unamended control soil. Results shows that relative to the unamended soil, iodine leaching was decreased by all amendments but that the magnitude of the decreases varied with the soil amendment applied. Iodine content was highest in the upper layer of the soil columns and decreased progressively with soil depth. The model was evaluated via comparison of the model simulated values with measured values from the soil column studies. The results showed that the HYDRUS 1D model efficiency was near to 1, indicating that the stimulated results were near to the measured values. Therefore, this study showed that iodine leaching through a soil could be ascertained well using a HYDRUS 1D model. The model over predicted iodine leaching, resulting to a weak correspondence between the simulated and the measured results for iodine leaching. This suggests that the HYDRUS-1D model does not explain accurately different organic and inorganic amended soil and the preferential flow that occurs in these columns. This may be due to the fact that Freundlich isotherm, which is part of the transport equations, does not sufficiently describe the mechanism of iodine adsorption onto the soil particles. This study would help to select amendments for an effective management strategy to reduce exogenous iodine losses from agro-ecosystems. This would also improve understanding of iodine transport in soil profile.
REVIEW | doi:10.20944/preprints202010.0159.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: Thyroid carcinoma; non-coding RNA; radioactive iodine; drug resistance; prognosis
Online: 7 October 2020 (14:28:40 CEST)
Thyroid cancer is the most prevalent malignancy of the endocrine system and the ninth most common cancer globally. Despite the advances in the management of thyroid cancer, there are critical issues with the diagnosis and treatment of thyroid cancer that result in the poor overall survival of undifferentiated and metastatic thyroid cancer patients. Recent studies have revealed the role of different non-coding RNAs (ncRNAs), such as microRNAs (miRNAs), long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs) that are dysregulated during thyroid cancer development or the acquisition of resistance to therapeutics, and may play key roles in treatment failure and poor prognosis of the thyroid cancer patients. Here, we systematically review the emerging roles and molecular mechanisms of ncRNAs that regulate thyroid tumorigenesis and drug response. We then propose the potential clinical implications of ncRNAs as novel diagnostic and prognostic biomarkers for thyroid cancer.
ARTICLE | doi:10.20944/preprints202302.0409.v1
Subject: Chemistry And Materials Science, Applied Chemistry Keywords: Activated carbon; Acacia seed pods; Methylene blue; Iodine number; Phosphoric acid
Online: 23 February 2023 (10:25:25 CET)
Due to its high specific surface area and rich porous structure, acacia-derived porous activated carbon is the most potentially effective material for wastewater treatment. This research study aimed to prepare activated carbon using Acacia erioloba seedpods as carbonaceous materials and phosphoric acid as an activating agent. The specific surface area of the prepared activated carbon sample was characterised by Brunauer–Emmett–Teller instrument. The specific surface area value was 387 m2/g. The activated carbon prepared was then sieved into three different particle sizes of 50, 100 and 200 micrometres and characterised using various analytical procedures, including proximate analysis to study moisture content, ash content, volatile matter content and fixed carbon content. The bulk density, SEM, power of hydrogen, iodine number and methylene blue number index were also investigated to determine the adsorption properties of the prepared activated carbon. Batch adsorption dynamics for the removal of organic compounds such as methylene blue and unsaturated character of fatty acid from aqueous solution were also carried out at room temperature to evaluate the prepared activated carbon's applicability in water treatment. The iodine number was 528, 638, and 554 mg/g for the 50, 100, and 200 μm activated carbon particles, respectively. From the results, the adsorption of methylene blue favoured the Freundlich adsorption model, showing higher correlation (R2) values than the Langmuir model. The results indicate that methylene blue particles were adsorbed on heterogeneous surfaces.
ARTICLE | doi:10.20944/preprints201902.0001.v2
Subject: Chemistry And Materials Science, Analytical Chemistry Keywords: color; free fatty acids; iodine absorption value; paraanisidine value; peroxide value
Online: 6 February 2019 (06:36:41 CET)
Deep fat frying is not novel, but a classical antiquity culinary technique preferred chiefly for its swiftness, amenity, conferment of a crisp texture, attractive sensorial and organoleptic qualities and thus delectableness of the fries. Regrettably, repeated use of oils for deep frying impacts the storage life and nutritional suitability of fries. This concerted study investigated the effects of continuous deep fat frying on the physicochemical properties of ten brands of edible cooking oils: Fortune Butto, Roki, Tamu, Best Fry, Golden Fry, Mukwano, Sunny, Sunvita, Sunlite and Sunseed used in deep frying of potato chips in Kampala, Uganda. Three oil samples from local Irish chip fryers were also collected. The color value (CV) and the acidification of the oils as free fatty acid (FFA), peroxide value (POV), paraanisidine value (AnV) and iodine adsorption value (IV) before and between ten successive deep-fryings using potato chips were determined. The possible reuse of the oils was estimated from the frying round when a quality criterion surpassed national or CODEX specifications for the respective edible cooking oils. For fresh oils, the statistical parameter ranges were: CV (0.4R 3.4Y-7.7R 70Y), % FFA (0.0430-0.1508), POV (0.5951-6.6134 meqO2/Kg), AnV (0.90-4.30) and IV (57.62-128.35gI2/100g). By the tenth fry, the values were respectively 3.0R 23Y-20.4R 70Y, 0.2286-0.4817, 11.1138-15.7525 meqO2/Kg, 10.31-22.16 and 53.66-126.03 gI2/100g. Reuse of the oils for continuous frying of potatoes on the same day can be done only up to 7 times on average for hard oils and 6 times for soft oils.
ARTICLE | doi:10.20944/preprints202307.1246.v1
Subject: Chemistry And Materials Science, Materials Science And Technology Keywords: micro/nano-porous graphite; iodine; fission products; diffusion; high temperature; rutherford backscattering spectrometry
Online: 19 July 2023 (08:24:26 CEST)
Using analysis methods such as Rutherford backscattering Spectrometry, scanning electron microscopy, X-ray diffraction, and Raman spectroscopy, the diffusion behavior of iodine in micro/nano-porous graphite under high-temperature conditions was studied. The results indicate that iodine diffusion leads to the contraction of graphite microcrystals, a decrease in interlayer spacing, and an increase in defect density, resulting in a reduction in microcrystal size. Upon diffusion of iodine out of iodine-loaded graphite, the microcrystal size of the graphite increases, the interlayer spacing appears to return to the initial state, and the defect density decreases. By comparing the iodine diffusion performance of nanoporous graphite G400 and G450 with microporous graphite G500, it was determined that nanoporous graphite exhibits better inhibition of iodine diffusion compared to microporous graphite. Studying the diffusion behavior of iodine in micro/nano-porous graphite has significant academic significance and engineering value for the screening, design, and performance optimization of nuclear graphite.
ARTICLE | doi:10.20944/preprints201908.0253.v1
Subject: Chemistry And Materials Science, Medicinal Chemistry Keywords: halogen bonding; fluorine; iodine; pentafluorosulfanyl; titration; ab initio calculation; NMR study; drug design
Online: 25 August 2019 (15:41:59 CEST)
The activation of halogen bonding by the substitution of the pentafluorosulfanyl (SF5) group was studied using a series of SF5-substituted iodobenzenes. The simulated electrostatic potential values of SF5-substituted iodobenzenes, ab initio molecular orbital calculations of intermolecular interactions of SF5-substituted iodobenzenes with pyridine, and the 13C NMR titration experiments of SF5-substituted iodobenzenes in the presence of pyridine or tetra (n-butyl) ammonium chloride (TBAC) indicated the obvious activation of halogen bonding, although this was highly dependent on the position of SF5-substitution on the benzene ring. 3,5-Bis-SF5-iodobenzene was the most effective halogen bond donor followed by o-SF5-substituted iodobenzene, while the m- and p-SF5 substitutions did not activate the halogen bonding of iodobenzenes. The 2:1 halogen bonding complex of 3,5-bis-SF5-iodobenzene and 1,4-diazabicyclo[2.2.2]octane (DABCO) was also confirmed. Since SF5-containing compounds have emerged as promising novel pharmaceutical and agrochemical candidates, the 3,5-bis-SF5-iodobenzene unit should be an attractive fragment of rational drug design capable of halogen bonding with biomolecules.
ARTICLE | doi:10.20944/preprints202307.0262.v1
Subject: Medicine And Pharmacology, Pharmacology And Toxicology Keywords: DCL ligand; iodine radioisotopes; radiolabeled pharmaceuticals; targeted delivery; prostatic specific membrane antigen; prostate cancer
Online: 5 July 2023 (04:43:46 CEST)
Prostate-specific membrane antigen (PSMA) has been identified as a target for the development of theranostic agents. In our current work, we describe the design and synthesis of novel N-[N-[(S)-1,3-dicarboxypropyl]carbamoyl]-(S)-L-lysine (DCL) urea-based PSMA inhibitors with a chlorine-substituted aromatic fragment at the lysine ε-nitrogen atom, a dipeptide as peptide fragment of the linker, including two phenylalanine residues in the L-configuration, and 3- or 4-(tributylstannyl)benzoic acid as prosthetic group in their structures for radiolabeling. The standard compounds ([127I]PSMA-m-IB and [127I]PSMA-p-IB) for comparative and characterization studies were firstly synthesized using two alternative synthetic approaches. An important advantage of the alternative synthetic approach in which the prosthetic group (NHS-activated esters of compounds) is first conjugated with the polypeptide sequence, followed by replacement of the Sn(Bu)3 group with radioiodine, is that the radionuclide is introduced in the final step of synthesis, thereby minimizing operating time with iodine-123 during the radiolabeling process. The obtained DCL urea-based PSMA inhibitors were radiolabeled with iodine-123. The radiolabeling optimization results showed that the radiochemical yield of [123I]PSMA-p-IB was higher than those of [123I]PSMA-m-IB, which were 74.9± 1.0% and 49.4 ± 1.2%, respectively. The radiochemical purity of [123I]PSMA-p-IB after purification was greater than 99.50%. The initial preclinical evaluation of [123I]PSMA-p-IB demonstrated a considerable affinity and specific binding to PC-3 PIP (PSMA-expressing cells) in vitro. The in vivo biodistribution of this new radioligand [123I]PSMA-p-IB showed less accumulation than [177Lu]Lu-PSMA-617 in several normal organs (liver, kidney and bone). These results warrants further preclinical development including toxicology evaluation and experiments in tumor-bearing mice.
ARTICLE | doi:10.20944/preprints202305.2034.v1
Subject: Public Health And Healthcare, Public Health And Health Services Keywords: iodine deficiency; glucose challenge test; large for gestational age; thyroglobulin; io-dine-containing supplements; maternal dysglycemia
Online: 30 May 2023 (04:08:48 CEST)
It is unclear how maternal glycemic status and maternal iodine status influence birth weight in mild-to-moderate iodine deficiency (ID). We studied the association between birth weight and both maternal glucose levels and iodine intake in pregnant women with mild-to-moderate ID. Glucose values were assessed using a glucose challenge test (GCT), non-fasting glucose before delivery; iodine status was assessed using an iodine food frequency questionnaire, serum thyroglobulin (Tg) and urinary iodine concentrations (UIC). Thyroid antibodies and free thyroxine (FT4) were measured. Obstetric and an-thropometric data were also collected. Large for gestational age (LGA) was predicted using a Cox proportional hazards model with multiple confounders. Tg>13g/L was in-dependently associated with LGA (adjusted hazard ratio = 3.4, 95% CI: 1.4–10.2, p=0.001). Estimated iodine intake correlated with FT4 among participants reporting io-dine-containing supplements (ICS) after adjusting for confounders (β = 0.4 95 %CI: 0.0002-0.0008, p=0.001). Newborn weight percentiles were inversely correlated with maternal FT4 values (β=-0.2 95 %CI:-0.08 - -56.49, p=0.049). We conclude that in mild-to-moderate ID regions, maternal insufficient iodine status may increase LGA risk. Iodine status and ICS intake may modify the effect maternal dysglycemia has on offspring weight.