59 research outputs found

    Neoflavonoids as Inhibitors of HIV-1 Replication by Targeting the Tat and NF-kB Pathways

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    Twenty-eight neoflavonoids have been prepared and evaluated in vitro against HIV-1. Antiviral activity was assessed on MT-2 cells infected with viral clones carrying the luciferase reporter gene. Inhibition of HIV transcription and Tat function were tested on cells stably transfected with the HIV-LTR and Tat protein. Seven 4-phenylchromen-2-one derivatives showed HIV transcriptional inhibitory activity but only the phenylchrome-2-one 10 inhibited NF- B and displayed anti-Tat activity simultaneously. Compounds 10, 14, and 25, inhibited HIV replication in both targets at concentrations <25 M. The assays of these synthetic 4-phenylchromen-2-ones may aid in the investigation of some aspects of the anti-HIV activity of such compounds and could serve as a scaffold for designing better anti-HIV compounds, which may lead to a potential anti-HIV therapeutic dru

    3-Phenylcoumarins as Inhibitors of HIV-1 Replication

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    We have synthesized fourteen 3-phenylcoumarin derivatives and evaluated their anti-HIV activity. Antiviral activity was assessed on MT-2 cells infected with viral clones carrying the luciferase gene as reporter. Inhibition of HIV transcription and Tat function were tested on cells stably transfected with the HIV-LTR and Tat protein. Six compounds displayed NF-ÎşB inhibition, four resulted Tat antagonists and three of them showed both activities. Three compounds inhibited HIV replication with IC50 values < 25 ÎĽM. The antiviral effect of the 4-hydroxycoumarin derivative 19 correlates with its specific inhibition of Tat functions, while compound 8, 3-(2-chlorophenyl)coumarin, seems to act through a mechanism unrelated to the molecular targets considered in this research

    Catheter Colonization and Abscess Formation Due to Staphylococcus epidermidis with Normal and Small-Colony-Variant Phenotype Is Mouse Strain Dependent

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    Coagulase-negative staphylococci (CoNS) form a thick, multilayered biofilm on foreign bodies and are a major cause of nosocomial implant-associated infections. Although foreign body infection models are well-established, limited in vivo data are available for CoNS with small-colony-variant (SCV) phenotype described as causative agents in implant-associated infections. Therefore, we investigated the impact of the Staphylococcus epidermidis phenotype on colonization of implanted PVC catheters and abscess formation in three different mouse strains. Following introduction of a catheter subcutaneously in each flank of 8- to 12-week-old inbred C57BL/6JCrl (B6J), outbred Crl:CD1(ICR) (CD-1), and inbred BALB/cAnNCrl (BALB/c) male mice, doses of S. epidermidis O-47 wild type, its hemB mutant with stable SCV phenotype, or its complemented mutant at concentrations of 106 to 109 colony forming units (CFUs) were gently spread onto each catheter. On day 7, mice were sacrificed and the size of the abscesses as well as bacterial colonization was determined. A total of 11,500 CFUs of the complemented mutant adhered to the catheter in BALB/c followed by 9,960 CFUs and 9,900 CFUs from S. epidermidis wild type in BALB/c and CD-1, respectively. SCV colonization was highest in CD-1 with 9,500 CFUs, whereas SCVs were not detected in B6J. The minimum dose that led to colonization or abscess formation in all mouse strains was 107 or 108 CFUs of the normal phenotype, respectively. A minimum dose of 108 or 109 CFU of the hemB mutant with stable SCV phenotype led to colonization only or abscess formation, respectively. The largest abscesses were detected in BALB/c inoculated with wild type bacteria or SCV (64 mm2 vs. 28 mm2). Our results indicate that colonization and abscess formation by different phenotypes of S. epidermidis in a foreign body infection model is most effective in inbred BALB/c followed by outbred CD-1 and inbred B6J mice

    Estrous cycle staging before mating led to increased efficiency in the production of pseudopregnant recipients without negatively affecting embryo transfer in mice

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    The goal was to increase pseudopregnant mice production by estrous cycle staging by visual examination before pairing and to determine the effect of such pseudopregnant recipients on embryo transfer. To compare methods of estrous cycle staging over 14 days, groups consisted of 10 females in proestrus-estrus and 10 vasectomized males; group 1: only daily visual observation; group 2: daily visual observation and cytological examination on day 1; group 3: daily visual observation and daily cytological examination. The average time to first vaginal plug was 1.8 days in group 1, 2.7 days in group 2, and 3.2 days in group 3, whereas the average time between consecutive vaginal plugs was 9.2 days (group I), 10 days (group 2), and 9.25 days (group 3). The average time between consecutive estrous cycles was 9.7 days (group 1),11.8 days (group 2), and 9.4 days (group 3). The congruence between visual and cytological examination in determining proestrus-estrus in group 2 was 100% and that for the four stages in group 3 was 79% with a range of 44% to 100%. From 162 plug-positive females originally selected in proestrus-estrus, 49%, 30%, 19%, and 2% were plug-positive on Day 1, Day 2, Day 3, and Day 4, respectively, showing that pseudopregnant mice production was significantly increased on the first 2 days. From 192 plug-positive females originally selected randomly, these values were 31%, 21%, 35%, 10%, and 3% on d1, d2, d3, d4, and d5, respectively. No significant differences were observed between groups with respect to embryo transfers with fresh or cryopreserved embryos although the number of pups born per litter was higher in group A with fresh (7.57 vs. 6.39) and cryopreserved-thawed embryos (5.0 vs. 4.38). Furthermore, the sex ratio and the genotype of the pups were not significantly affected. (C) 2016 Elsevier Inc. All rights reserved

    Rodent and Germplasm Trafficking: Risks of Microbial Contamination in a High-Tech Biomedical World Prevalence and Persistence of Pathogens in Mice

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    Abstract High-tech biomedical advances have led to increases both in the number of mice used for research and in exchanges of mice and/or their tissues between institutions. The latter are associated with the risk of dissemination of infectious agents. Because of the lack of international standardization of health surveillance programs, health certificates for imported rodents may be informative but may not address the needs of the importing facility. Preservation of mouse germplasm is achieved by cryopreservation of spermatozoa, embryos, or ovaries, and embryonic stem cells are used for the production of genetically engineered mice. After embryo transfer, recipients and rederived pups that test negative in microbiological screening for relevant microorganisms are released into full barrier holding areas. However, current research shows that embryos may also transmit microorganisms, especially viruses, to the recipient mice. In this article, we discuss regulations and practical issues in the shipping of live mice and mouse tissues, including spermatozoa, embryos, ovaries, and embryonic stem cells, and review work on microbial contamination of these biological materials. In addition, we present ways to reduce the risk of transmission of pathogens to mice under routine conditions

    D-aspartate treatment in vitro improves mouse sperm fertility in young B6N mice

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    We previously reported that the administration of D-aspartate (D-Asp) in drinking water over a 2-4-week period to 7-week-old mice resulted in higher sperm quality and increased in vitro fertilisation (IVF) rates associated with a systemic increase of luteinizing hormone and testosterone levels in the serum. The goal of this study was to investigate the effects of in vitro treatment with D-Asp on the IVF rate, embryo transfer, and sperm parameters of cryopreserved-thawed C57BL/6NTacCnrm (B6N) spermatozoa derived from young and adult mice. In this study, cryopreserved-thawed B6N spermatozoa from males aging 9, 11, 13, and 16 weeks were treated for 1 h with 4 mM D-Asp during capacitation. Thereafter, the in vitro fertilisation ability and the embryo transfer efficiency were analysed. Also, the kinetic activity of the treated spermatozoa and the acrosome reaction were measured after 1 h, 2 h, and 5 h of incubation. The capacitation rate of spermatozoa was determined after 1 h of pre-incubation. Spermatozoa from 9- and 11-week-old mice, which were treated with D-Asp, led to significantly increased IVF rates. However, spermatozoa derived from 13- and 16-week-old mice did not lead to a significant improvement in the fertilisation rate. At all ages examined, no differences were observed in the birth rate and sperm kinetic parameters. After 1 h incubation under the same conditions as the IVF was performed, the capacitation rate and the acrosome reaction were significantly higher with the D-Asp-treated spermatozoa from 9-week-old (67.5% vs. 41% and 14.5% vs. 10.5%, respectively) and 11-week-old mice (78.5% vs. 41.1% and 21.0% vs. 3.8%, respectively), corresponding to the improved IVF results. Therefore, the present results demonstrate, for the first time, a direct role of D-Asp in the capacitation process and acrosome reaction. (C) 2020 Elsevier Inc. All rights reserved

    Influence of polygamous versus monogamous mating on embryo production in four different strains of mice after superovulatory treatment

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    We determined the effect of monogamous or polygamous mating with 2 females on vaginal plug (VP) rate, embryo donors (ED), 2-cell embryo production, and male performance after superovulation of females aging 24d or 45-48d. C57BL/6NCrl (B6N), BALB/cAnCrl (BALB/cN), FVB/NCrl (FVB/N), and Crl:CD1(ICR) (CD-1) females received 5 IU eCG and 5 IU hCG (24d) or 7.5 IU eCG and 7.5 IU hCG (45-48d) 48 h apart. After the hCG injection, females were paired with males, which alternated weekly in monogamous or polygamous mating. Significant differences in the percentage of VP-positive females between monogamous and polygamous mating were observed for B6N (71% vs. 49%), FVB/N (77% vs. 51%), and CD-1 (90% vs. 67%) at 45-48d. BALB/cN and CD-1 showed higher VP rates than B6N and FVB/N. A significantly higher percentage of ED was found for monogamous than for polygamous mating for FVB/N (87% vs. 61%) at 24d and for B6N (91% vs. 53%) and CD-1 (90% vs. 68%) at 45-48d. In all strains of mice and in both age groups, no significant differences were observed in the number of intact 2-cells per VP-positive female, ED or treated female between monogamous and polygamous mating except in the B6N strain where monogamous mating resulted in a significantly higher number of intact 2-cell embryos per treated female than polygamous mating at both ages. The present results imply that polygamous mating can be implemented for 2-cell embryo production in all strains studied except for B6N when all females are euthanized. However, when only VP+ females are sacrificed polygamous mating can be employed for all 4 strains studied. (C) 2018 Elsevier Inc. All rights reserved
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