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BACKGROUND: Cyclosporin A is widely used in Mexico as immunosuppressive therapy in organ transplantation and in the treatment of autoimmune disorders. Although several generic oral formulations of cyclosporin A are available in Mexico, information concerning the bioequivalence of these formulations in the Mexican population is not available in the published literature. OBJECTIVE: The aim of this study was to compare the bioequivalence and tolerability of a generic (test) and a branded (reference) soft-gelatin capsule formulation of cyclosporin A microemulsion 100 mg available in Mexico. METHODS: This randomized, open-label, 2-period cross-over study was performed at the Universidad Autónomade Nuevo León, Monterrey, México. Eligible subjects were healthy male volunteers who were randomly assigned to receive a single 100-mg dose of the test or reference formulation, followed by a 2-week washout period and administration of the alternate formulation. Doses were administered after a 12-hour overnight fast. For analysis of pharmacokinetic properties, including C(max), AUC(0-t), and AUC(0-infinity) , blood samples were obtained at intervals over the 48-hour period after dosing. The formulations were considered bioequivalent if the log-transformed ratios of Cma x and AUC were within the predetermined equivalence range (80%-125%). Tolerability was assessed by monitoring vital signs and laboratory tests (hematology, blood biochemistry, hepatic function, and urinalysis), and by questioning subjects about adverse events. RESULTS: Thirty-six male subjects (mean age, 22.08 years [range, 18-29 years]; mean weight, 78.23 kg [range, 72-89 kg]; mean height, 177 cm [range, 169-185 cm]) were enrolled in the study, and 34 (17 each randomized to receive the test or reference formulation first) completed it. No period or sequence effect was observed. The 90% CIs for the log-transformed ratios of C(max), AUC(0-t), and AUC(0-infinity) were 85.12 to 92.85, 92.14 to 99.75, and 92.19 to 99.72, respectively (all, P <0.05). Similar results were found for the data without log-transformation. No adverse events occurred or were reported by patients during the study. CONCLUSIONS: In this small study in healthy adult male Mexican volunteers, a single 100-mg dose of the test formulation was bioequivalent to a single 100-mg dose of the reference formulation based on the regulatory definition (rate and extent of absorption). Both formulations were well tolerated. [ABSTRACT FROM AUTHOR]

Now in its 25th year, the Mutant Mouse Resource and Research Center (MMRRC) consortium continues to serve the United States and international biomedical scientific community as a public repository and distribution archive of laboratory mouse models of human disease for research. Supported by the National Institutes of Health (NIH), the MMRRC consists of 4 regionally distributed and dedicated vivaria, offices, and specialized laboratory facilities and an Informatics Coordination and Service Center (ICSC). The overarching purpose of the MMRRC is to facilitate groundbreaking biomedical research by offering an extensive repertoire of mutant mice that are essential for advancing the understanding of human physiology and disease. The function of the MMRRC is to identify, acquire, evaluate, characterize, cryopreserve, and distribute mutant mouse strains to qualified biomedical investigators around the nation and the globe. Mouse strains accepted from the research community are held to the highest scientific standards to optimize reproducibility and enhance scientific rigor and transparency. All submitted strains are thoroughly reviewed, documented, and validated using extensive scientific quality control measures. In addition, the MMRRC conducts resource-related research on cryopreservation, mouse genetics, environmental conditions, and other topics that enhance operations of the MMRRC. Today, the MMRRC maintains an archive of mice, cryopreserved embryos and sperm, embryonic stem (ES) cell lines, and murine hybridomas for nearly 65,000 alleles. Since its inception, the MMRRC has fulfilled more than 20,000 orders from 13,651 scientists at 8441 institutions worldwide. The MMRRC also provides numerous services to assist researchers, including scientific consultation, technical assistance, genetic assays, microbiome analysis, analytical phenotyping, pathology, cryorecovery, husbandry, breeding and colony management, infectious disease surveillance, and disease modeling. The ICSC coordinates MMRRC operations, interacts with researchers, and manages the website (mmrrc.org) and online catalogue. Researchers benefit from an expansive list of well-defined mouse models of disease that meet the highest scientific standards while submitting investigators benefit by having their mouse strains cryopreserved, protected, and distributed in compliance with NIH policies., (© 2024. The Author(s).)

The Mouse Metabolic Phenotyping Center (MMPC)Live Program was established in 2023 by the National Institute for Diabetes, Digestive and Kidney Diseases (NIDDK) at the National Institutes of Health (NIH) to advance biomedical research by providing the scientific community with standardized, high quality phenotyping services for mouse models of diabetes and obesity. Emerging as the next iteration of the MMPC Program which served the biomedical research community for 20 years (2001-2021), MMPCLive is designed as an outwardly-facing consortium of service cores that collaborate to provide reduced-cost consultation and metabolic, physiologic, and behavioral phenotyping tests on live mice for U.S. biomedical researchers. Four MMPCLive Centers located at universities around the country perform complex and often unique procedures in vivo on a fee for service basis, typically on mice shipped from the client or directly from a repository or vendor. Current areas of expertise include energy balance and body composition, insulin action and secretion, whole body carbohydrate and lipid metabolism, cardiovascular and renal function, food intake and behavior, microbiome and xenometabolism, and metabolic pathway kinetics. Additionally, an opportunity arose to reduce barriers to access and expand the diversity of the biomedical research workforce by establishing the VIBRANT Program. Directed at researchers historically underrepresented in the biomedical sciences, VIBRANT-eligible investigators have access to testing services, travel and career development awards, expert advice and experimental design consultation, and short internships to learn test technologies. Data derived from experiments run by the Centers belongs to the researchers submitting mice for testing which can be made publicly available and accessible from the MMPCLive database following publication. In addition to services, MMPCLive staff provide expertise and advice to researchers, develop and refine test protocols, engage in outreach activities, publish scientific and technical papers, and conduct educational workshops and training sessions to aid researchers in unraveling the heterogeneity of diabetes and obesity., (© 2024. The Author(s).)

Atorvastatin is widely recommended for long-term secondary prevention in STEMI patients with no contraindication. Although high-dose atorvastatin has been shown to reduce important patient outcomes such as MACE, there is still doubt that high-dose atorvastatin could have the same protective effect in patients undergoing PCI in the short and long term. We searched the following electronic databases: Scopus, Web of Science, MEDLINE, EMBASE, and Cochrane Central considering studies that enrolled adult patients with a confirmed diagnosis of STEMI or NSTEMI undergoing PCI. The intervention must have been atorvastatin alone compared to a placebo, standard care, or a different atorvastatin dose. A total of (n = 11) studies were included in the quantitative analysis. Information on (N = 5,399) patients was available; 2,654 were assigned to receive high-dose atorvastatin therapy, and 2,745 comprised the control group. High-dose atorvastatin pre-loading significantly reduced MACE at one month of follow-up (RR: 0.78; 95% CI: 0.67-0.91; p = 0.014) in both STEMI and NSTEMI. All-cause mortality was reduced in patients with STEMI (RR: 0.28; 95% CI: 0.10-0.81; p = 0.029). The quality of the body of evidence was rated overall as moderate. Patients presenting with STEMI or NSTEMI benefit from high-dose atorvastatin pre-loading before PCI by reducing MACE at 30 days. The use of high-dose atorvastatin in STEMI patients reduced all-cause mortality. The beneficial effects of atorvastatin pre-loading are limited to 30 days post-PCI., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 García-Campa et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

As part of the Reproducibility Project: Cancer Biology, we published Registered Reports that described how we intended to replicate selected experiments from 29 high-impact preclinical cancer biology papers published between 2010 and 2012. Replication experiments were completed and Replication Studies reporting the results were submitted for 18 papers, of which 17 were accepted and published by eLife with the rejected paper posted as a preprint. Here, we report the status and outcomes obtained for the remaining 11 papers. Four papers initiated experimental work but were stopped without any experimental outcomes. Two papers resulted in incomplete outcomes due to unanticipated challenges when conducting the experiments. For the remaining five papers only some of the experiments were completed with the other experiments incomplete due to mundane technical or unanticipated methodological challenges. The experiments from these papers, along with the other experiments attempted as part of the Reproducibility Project: Cancer Biology, provides evidence about the challenges of repeating preclinical cancer biology experiments and the replicability of the completed experiments., Competing Interests: TE Employed by the nonprofit Center for Open Science that has a mission to increase openness, integrity, and reproducibility of research, AD Was employed by the nonprofit Center for Open Science that has a mission to increase openness, integrity, and reproducibility of research, AA, KH No competing interests declared, RA, LB, JC, SD, TT, BW, JW Employed by the University of California, Davis Mouse Biology Program, a Science Exchange associated lab during experimentation, PA Was employed by Cancer Metabolism Facility at Sanford Burnham Prebys Medical Discovery Institute, a Science Exchange associated lab during experimentation, HC, JK, VS, AT, LY Employed by Applied Biological Materials, a Science Exchange associated lab during experimentation, CD, BH, EM, MS Was employed by TGA Sciences, a Science Exchange associated lab during experimentation, EI Employed by and hold shares in Science Exchange Inc, SP Employed by Kinexus Bioinformatics Corporation, a Science Exchange associated lab during experimentation, NP, RT Was employed by and hold shares in Science Exchange Inc, AP Was employed by Applied Biological Materials, a Science Exchange associated lab during experimentation, DS Employed by BioFactura, a Science Exchange associated lab during experimentation, DS Employed by Cancer Metabolism Facility at Sanford Burnham Prebys Medical Discovery Institute, a Science Exchange associated lab during experimentation, (© 2021, Errington et al.)

The mammalian brain relies on neurochemistry to fulfill its functions. Yet, the complexity of the brain metabolome and its changes during diseases or aging remain poorly understood. Here, we generate a metabolome atlas of the aging wildtype mouse brain from 10 anatomical regions spanning from adolescence to old age. We combine data from three assays and structurally annotate 1,547 metabolites. Almost all metabolites significantly differ between brain regions or age groups, but not by sex. A shift in sphingolipid patterns during aging related to myelin remodeling is accompanied by large changes in other metabolic pathways. Functionally related brain regions (brain stem, cerebrum and cerebellum) are also metabolically similar. In cerebrum, metabolic correlations markedly weaken between adolescence and adulthood, whereas at old age, cross-region correlation patterns reflect decreased brain segregation. We show that metabolic changes can be mapped to existing gene and protein brain atlases. The brain metabolome atlas is publicly available ( https://mouse.atlas.metabolomics.us/ ) and serves as a foundation dataset for future metabolomic studies., (© 2021. The Author(s).)

The mouse is the most commonly used model species in biomedical research. Just as human physical and mental health are influenced by the commensal gut bacteria, mouse models of disease are influenced by the fecal microbiome (FM). The source of mice represents one of the strongest influences on the FM and can influence the phenotype of disease models. The FM influences behavior in mice leading to the hypothesis that mice of the same genetic background from different vendors, will have different behavioral phenotypes. To test this hypothesis, colonies of CD-1 mice, rederived via embryo transfer into surrogate dams from four different suppliers, were subjected to phenotyping assays assessing behavior and physiological parameters. Significant differences in behavior, growth rate, metabolism, and hematological parameters were observed. Collectively, these findings show the profound influence of supplier-origin FMs on host behavior and physiology in healthy, genetically similar, wild-type mice maintained in identical environments.

Physical chitosan hydrogels are potential biomaterials for several biomedical applications, such as wound healing, tissue repair, and drug delivery. Controlling the microstructural organization of chitosan gels is one of the keys for monitoring the physical, mechanical, and biological properties. As a result, the main objective of the present work was to explore the microstructural organization of chitosan hydrogels in relation with the processing conditions of gelation. For this purpose, different gelation routes were studied, that is, chitosan solution neutralization of an aqueous or hydroalcoholic solution and neutralization of an alco-gel. Overall, the resulting morphology after processing was determined by the medium viscosity during neutralization and the nature and concentration of the base. The effect of these processing parameters on the morphology was evaluated mainly through small angle light scattering (SALS) measurements including in situ measurements during chitosan neutralization. As a result, we reported different bulk microstructures consisting in 200-400 nm aggregates (primary particles) agglomerated into micrometer range clusters or arranged into more organized structures, that is, forming microchannels (4-6 μm). We thus established a qualitative and quantitative relation between supramolecular morphology and gelation conditions of chitosan hydrogels.

Background: The proprietary form of topiramate is indicated in Mexico as an antiepileptic agent and in the prophylaxis of migraine headaches. However, before generic topiramate is placed on the market, pharmacokinetic studies investigating the bioequivalence of generic and branded formulations are needed., Objective: The aim of this study was to compare the bioequivalence and tolerability of a generic (test) and a branded (reference) formulation of topiramate 100 mg in healthy Mexican volunteers., Methods: This open-label, randomized-sequence, 2-period crossover study was conducted at Ipharma SA de CV, Monterrey, Mexico. Eligible subjects were healthy male Mexican volunteers aged 18 to 45 years. Participants were randomly assigned to receive 100 mg of the test or reference formulation, followed by a 3-week washout period and administration of the alternate formulation. Doses were administered after a 12-hour overnight fast. For analysis of pharmacokinetic properties, including C(max), AUC(0-t), and AUC(0-infinity), blood samples were obtained over a 144-hour period after dosing. The formulations were to be considered bioequivalent if calculations of a 90% CI for the ratio of the means of the measures for the test and reference formulations fell within bioequivalence limits, 80% to 125%, for logarithmic (log) transformation of C(max) and AUC, and if two 1-sided t tests showed P < 0.05. Tolerability was assessed using vital sign measurement (blood pressure, body temperature, heart rate, and respiratory rate), laboratory analysis (hematology, blood biochemistry, hepatic function, and urinalysis), and subject interview., Results: Twenty-eight men (mean age, 22.21 years [range, 18-28 years]; mean weight, 75.04 kg [range, 62-96 kg]; mean height, 177 cm [range, 163-192 cm]) were enrolled in this study, and 28 (14 each randomized to receive the test or reference formulation first) completed it. No period or sequence effects were observed. The 90% CIs for the log-transformed C(max), AUC(0-t) and AUC(0-infinity) were 94.70 to 112.05, 98.88 to 105.16, and 98.80 to 105.28, respectively (all, P < 0.05). No adverse events were reported by the volunteers or found on clinical laboratory testing during the study., Conclusions: This study did not find any statistically significant differences in C(max) or AUC values between the test and reference formulations of oral topiramate 100 mg in this population of healthy adult male Mexican volunteers. On that basis, and according to both the rate and extent of absorption, the test and reference formulations met the regulatory criteria for bioequivalence. Both formulations were well tolerated.

As ribonucleic acid (RNA) molecules play important roles in many biological processes including gene expression and regulation, their secondary structures have been the focus of many recent studies. Despite the computing power of supercomputers, computationally predicting secondary structures with thermodynamic methods is still not feasible when the RNA molecules have long nucleotide sequences and include complex motifs such as pseudoknots. This paper presents RNAVLab (RNA Virtual Laboratory), a virtual laboratory for studying RNA secondary structures including pseudoknots that allows scientists to address this challenge. Two important case studies show the versatility and functionalities of RNAVLab. The first study quantifies its capability to rebuild longer secondary structures from motifs found in systematically sampled nucleotide segments. The extensive sampling and predictions are made feasible in a short turnaround time because of the grid technology used. The second study shows how RNAVLab allows scientists to study the viral RNA genome replication mechanisms used by members of the virus family Nodaviridae.

Background: Loratadine is a long-acting antihistamine with selective peripheral histamine H(1)-receptor antagonistic activity and fewer sedative effects compared with conventional antihistamines, and is widely used in Mexico. Although several generic formulations of loratadine are available in Mexico, based on a literature search, information concerning the bioavailability of each formulation in the Mexican population is not available., Objective: The aim of this study was to compare the bioavailability and tolerability of 2 oral formulations of loratadine 20 mg (two 10-mg tablets) used in Mexico: Sensibit (test formulation; Laboratorios Liomont S.A. de C.V., Mexico City, Mexico) and Clarityne (reference formulation; Schering-Plough S.A. de C.V., Mexico City, Mexico) in healthy volunteers., Methods: This open-label, randomized, 2-period crossover study was conducted at Universidad Autónoma de Nuevo León, Monterrey, Nuevo León, Mexico. Eligible subjects were healthy male Mexican volunteers aged > or=18 years. Subjects were randomly assigned to receive a single 20-mg dose (two 10-mg tablets) of the test or reference formulation, followed by a 2-week washout period, followed by the same dose of the alternate formulation. A 400-mg dose of ketoconazole (2 doses in 24 hours) was administered to each subject before the administration of each formulation, and a 200-mg dose of ketoconazole was given together with each formulation (ie, a total of 600 mg of ketoconazole was administered). Doses were administered after a 12-hour overnight fast. For analysis of pharmacokinetic properties, including C(maX), AUC(0-t), and AUC(0-infinity), blood samples were drawn at 0.25, 0.5, 0.75, 1, 1.25, 1.5, 2, 2.5, 3, 5, 8, 12, 16, and 22 hours after dosing. The formulations were considered bioequivalent if the geometric mean ratios of C(maX) and AUC were within the predetermined equivalence range of 80% to 125%. Tolerability was assessed by monitoring vital signs and subject interview regarding the potential presence of adverse events (AEs)., Results: Thirty-two subjects were enrolled in the study (mean age, 22 years [range, 18-28 years]; mean weight, 68.9 kg [range, 58-79 kg]; mean height, 170.8 cm [range, 158-183 cm]). Sixteen subjects received the test formulation first. No period or sequence effect was observed. The 90% CIs for the corresponding ratios of CmaX, AUC(0-t), and AUC(0-infinity) were 81.43% to 106.01%, 83.12% to 100.23%, and 84.06% to 101.10% (all, P < 0.05), meeting the predetermined criteria for bioequivalence. Similar results were found for data without a logarithmic transformation. No AEs were reported throughout the study., Conclusions: In this small study in healthy Mexican volunteers, a single, 20-mg dose of the test formulation of loratadine was found to be bioequivalent to that of the reference formulation based on the rate and extent of absorption when concomitantly administered with ketoconazole. Both formulations were well tolerated.

Background: Azithromycin is related to erythromycin but is more active against gram-negative bacteria and less active against streptococci and staphylococci compared with erythromycin. For these reasons, and because of convenience of dosing (QD for 3 days), azithromycin is widely used in Mexico. Although several generic formulations of azithromycin are available in Mexico, information concerning the bioavailability of each formulation in the Mexican population is not available., Objective: The aim of this study was to compare the bioavailability and tolerability of 2 oral formulations of azithromycin 500 mg used in Mexico: Macrozit (trademark of Laboratorios Liomont, S.A. de C.V., Mexico City, Mexico; test formulation) and Azitrocin (trademark of Pfizer, S.A. de C.V., Mexico City, Mexico; reference formulation)., Methods: This 2 x 2, crossover, randomized, open-label study was conducted at the Department of Pharmacology and Toxicology, Universidad Autóma de Nuevo Leon, Monterrey, Mexico. Eligible subjects were healthy volunteers of either sex and with the following characteristics: age > or =19 to 25 years, weight 54 to 77 kg, and height 159 to 177 cm. Subjects were randomly assigned to receive Macrozit followed by Azitrocin, or vice versa, with a 3-week washout period between doses. After a 12-hour (overnight) fast, subjects received a single, 500-mg dose of each formulation. For analysis of pharmacokinetic properties, including C(max), AUC(0-t), and AUC(0-infinity), blood samples were drawn at 0.5, 1, 1.5, 2, 2.5, 3, 4, 6, 12, 24, 48, 72, 96, and 120 hours after dosing. The formulations were considered bioequivalent if the logarithm (ln)-transformed ratios of C(max) and AUC were within the predetermined equivalence range of 80% to 125% and if P < or = 0.05 for the 90% CIs. Tolerability was assessed by monitoring and subject interview regarding the potential presence of adverse events (AEs)., Results: Twenty-eight subjects were enrolled in the study; 27 completed it (14 men, 13 women; mean age, 21.7 years). Fourteen subjects received the test formulation first. No period or sequence effect was observed. The 90% CIs for the corresponding ratios of C(max), AUC(0-t), and AUC(0-infinity) were 80.67 to 107.21, 91.39 to 107.59, and 90.61 to 106.19 (all, P < 0.05). Similar results were found for data without a logarithmic transformation. No AEs were found throughout the study., Conclusions: In this small study in healthy Mexican volunteers, a single, 500-mg dose of Macrozit was found to be bioequivalent to that of Azitrocin based on the rate and extent of absorption. Both formulations were well tolerated.