Microcystis aeruginosa is a common cyanobacteria found in water blooms and often causes ecological harm. Antibiotics are also increasingly used for the prevention and treatment of bacterial infections in aquaculture. However, since most antibiotics cannot be fully metabolized, they enter the water environment and cause ecological impacts. In this paper, the effects of the two quinolone antibiotics (enrofloxacin and ciprofloxacin) on the population density and microcystins (MCs) production of Microcystis aeruginosa were studied. It is of great significance for the ecological risk assessment of antibiotics to the water environment. The results showed that the 96h EC50 values of enrofloxacin and ciprofloxacin to Microcystis aeruginosa were 56.10mg/L and 49.80mg/L respectively, and the toxicity of ciprofloxacin to Microcystis aeruginosa was slightly stronger than that of enrofloxacin. With the increase of the two quinolone antibiotic concentration, the growth inhibition rate (IR) increased, but when the concentration reached a certain height, the IR would reach its threshold. Long-term exposure to low concentrations of these two quinolone antibiotics is not only more likely to lead to the outbreak of Microcystis aeruginosa, but also increase its toxin production capacity. The highest contents of MCs in enrofloxacin and ciprofloxacin groups were 95.539 μg/g and 93.720 μg/g, respectively. The MCs value of these three enrofloxacin treatment groups was more than above 51.8 times that of control group (CK) on the 4th day; from 8th day to 14th day, the MCs value of these three enrofloxacin treatment groups was more than above 3.2 times that of CK group. For another ciprofloxacin, the MCs value of the treatment group was more than 64.98 times that of the CK group on the 4th day, and from 8th day to 14th day, the MCs value of the treatment group was more than 2.7 times that of the CK group. These findings provide crucial management rationale.

INTRODUCTION: Superficial cutaneous bacterial infections have a high incidence in geriatric patients. The most implicated pathogens are gram-positive cocci (Staphylococcus aureus, Streptococcus pyogenes) while gram-negative germs are also implicated. Resistances to common topical antibiotics (mupirocin, fusidic acid) require alternatives to gram-positive and gram-negative microorganisms.Ozenoxacin cream for topical use (non-fluorinated bactericidal quinolone), in other countries and with other galenics, is indicated in children older than 6 months and in adults as a treatment of superficial bacterial infections, such as acne. In Spain, ozenoxacin cream is indicated only for non-bullous impetigo; scientific evidence show effectiveness also in other superficial skin bacterial infections.A cases series of clinical use of ozenoxacin in bacterial superficial skin infections in geriatric patients (institutionalized or community dwelling) is presented.METHODS: Multicenter case series (March-August 2022) of bacterial superficial skin infections treated with ozenoxacin cream (10mg/g every 12h, 5days); data from medical records (controls: 1-3-5 days), after obtaining informed consent (use of data and images).RESULTS: Series of 28 patients (mean age: 84,79) from nine nursing homes and one outpatient geriatric service, including acute and subacute/chronic cases.In all cases treatment was ozenoxacin 10mg/g topical cream applied every 12 hours for 5 days according to medical prescription (except for one case in which 3 days were enough for complete healing and another case treated for 10 days).Results showed complete healing in all 20 acute cases and significant clinical improvement in all subacute/chronic cases (with complete healing in one of them). Professionals scored the effectiveness in acute cases as a mean 4.5 points (maximum score: 5, p<.0001) and in subacute/chronic cases as 3.8 points (p=.010).There was no skin irritation or other adverse effects in anyone of the patients, and clinical improvement of pain, itching and other symptoms was observed, suggesting an anti-inflammatory effect. DISCUSSION AND CONCLUSIONS: Our results seem to demonstrate the effectiveness and tolerability of ozenozacin cream in bacterial infections other than non-bullous impetigo. Ozenoxacin cream is indicated only for the treatment of non-bullous impetigo; however, it is also shown to be effective, both in the scientific evidence and in our case series, for other superficial bacterial skin infections, both acute and subacute/chronic, suggesting the opportunity for clinical studies with an experimental design to evaluate the findings of clinical practice and to be able to have a therapeutic alternative to compensate for the complications of the appearance of resistance.

The quinolone decoquinate (DCQ) is widely used in veterinary practice for the treatment of bacte-rial and parasitic infections, most notably coccidiosis in poultry and in ruminants. We have in-vestigated the effects of treatment of Toxoplasma gondii in infected human foreskin fibroblasts (HFF) with DCQ. It induced distinct alterations in the parasite mitochondrion within 24h, which persisted even after long-term (500 nM, 52 days) treatment, although there was no parasiticidal effect. Based on the low half-maximal effective concentration (IC50) of 1.1 nM and the high selec-tivity index of >5000, the efficacy of oral treatment of pregnant mice experimentally infected with T. gondii oocysts with DCQ at 10 mg/kg/day for 5 days was assessed. However, the treatment had detrimental effects, induced higher neonatal mortality than T. gondii infection alone, and did not prevent vertical transmission. Thus, three quinoline-O-carbamate derivatives of DCQ antici-pated to have better physicochemical properties than DCQ were assessed in vitro. One such com-pound RMB060 displayed an exceedingly low IC50 of 0.07 nM when applied concomitantly with infection of host cells and had no impact on HFF viability at 10 µM. As was the case for DCQ, RMB060 treatment resulted in alteration of the mitochondrial matrix and loss of cristae, but the changes became apparent at just 6h after commencement of treatment. After 48h, RMB060 induced the expression of the bradyzoite antigen BAG1, but TEM did not reveal any other features remi-niscent of bradyzoites. Exposure of infected cultures to 300 nM RMB060 for 52 days did not re-sult in complete killing of all tachyzoites, although mitochondria remained ultrastructurally damaged and there was a slower proliferation rate. Treatment of mice infected with T. gondii oocysts with RMB060 did reduce parasite burden in non-pregnant mice and dams, but vertical transmission to pups could not be prevented.

Although phylogenetic analysis shows coronaviruses (CoV) share similar genome sequences, CoVs encode different number of proteins (5 to 14). The newly isolated viruses harbour more proteins than the old ones. Therefore, identifying the functional protein unites will benefits to understand the molecular interactions of the virus, and then identify molecular targets for antiviral drug. Here, the comparative in-silico analysis of 33 coronavirus proteomes show that coronaviruses harbour diverse number of protein functional motifs. Coronaviruses harbour wide-range of motifs including those involved in integrin-binding and ESCRT pathway before virus budding. For example, SARS-CoV-2, but not SARS-CoV-1, encodes PPxY motif, which is required for virus entry and budding of HIV, influenza and adenoviruses. The quinolone inulding the antiviral FGI-104 is able to block ESCRT pathway and viral budding and has been used against HIV, HCV and Ebola virus.

Chitosan decorated copper nanoparticles (CS/CuNPs) catalysts were synthesized via reduction methods utilizing green protocol. The CS/CuNPs hybrid catalysts were tested for the synthesis of quinoline derivatives utilizing one-pot multicomponent reaction (MCR) under ultrasonic irradiation. The best catalyst (CS/CuNPs) that provided good conversion reaction yield and high turnover frequency (TOF) was characterized using Fourier transform infrared (FTIR), Thermogravimetric analyses (TGA), X-ray diffraction (XRD), , scanning electron microscopy (SEM), transmission electron microscope (TEM) and X-ray photoelectron spectroscopy (XPS) techniques. Generalization of the scope of the proposed catalytic process was studied using different aldehydes. Excellent products yield and high TOF in even shorter reaction time (~5 min) was attained. Recyclability performance of the catalyst over five times re-use without detectable loss in product yield was recorded. The current method is green process utilizing environmentally benign catalyst and considered to be promising sustainable protocol for the synthesis of fine chemicals.