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Clostridioides difficile (C. difficile) is widely distributed in the intestinal tract of humans, animals, and in the environment. It is the most common cause of diarrhea associated with the use of antimicrobials in humans and among the most common healthcare-associated infections worldwide. Its pathogenesis is mainly due to the production of toxin A (TcdA), toxin B (TcdB), and a binary toxin (CDT), whose genetic variants may be associated with disease severity. We studied genetic diversity in 39 C. difficile isolates from adults and children attended at two Mexican hospitals, using different gene and genome typing methods and investigated their association with in vitro expression of toxins. Whole-genome sequencing in 39 toxigenic C. difficile isolates were used for multilocus sequence typing, tcdA, and tcdB typing sequence type, and phylogenetic analysis. Strains were grown in broth media, and expression of toxin genes was measured by real-time PCR and cytotoxicity in cell-culture assays. Clustering of strains by genome-wide phylogeny matched clade classification, forming different subclusters within each clade. The toxin profile tcdA+/tcdB+/cdt+ and clade 2/ST1 were the most prevalent among isolates from children and adults. Isolates presented two TcdA and three TcdB subtypes, of which TcdA2 and TcdB2 were more prevalent. Prevalent clades and toxin subtypes in strains from children differed from those in adult strains. Toxin gene expression or cytotoxicity was not associated with genotyping or toxin subtypes. In conclusion, genomic and phenotypic analysis shows high diversity among C. difficile isolates from patients with healthcare-associated diarrhea. IMPORTANCE: Clostridioides difficile is a toxin-producing bacterial pathogen recognized as the most common cause of diarrhea acquired primarily in healthcare settings. This bacterial species is diverse; its global population has been divided into five different clades using multilocus sequence typing, and strains may express different toxin subtypes that may be related to the clades and, importantly, to the severity and progression of disease. Genotyping of children strains differed from adults suggesting toxins might present a reduced toxicity. We studied extensively cytotoxicity, expression of toxins, whole genome phylogeny, and toxin typing in clinical C. difficile isolates. Most isolates presented a tcdA+/ tcdB+/cdt+ pattern, with high diversity in cytotoxicity and clade 2/ST1 was the most prevalent. However, they all had the same TcdA2/TcdB2 toxin subtype. Advances in genomics and bioinformatics tools offer the opportunity to understand the virulence of C. difficile better and find markers for better clinical use.
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Toxinas Bacterianas , Clostridioides difficile , Infecções por Clostridium , Infecção Hospitalar , Diarreia , Variação Genética , Tipagem de Sequências Multilocus , Filogenia , Humanos , Clostridioides difficile/genética , Clostridioides difficile/classificação , Clostridioides difficile/isolamento & purificação , Diarreia/microbiologia , Diarreia/epidemiologia , México/epidemiologia , Criança , Toxinas Bacterianas/genética , Adulto , Infecções por Clostridium/microbiologia , Infecções por Clostridium/epidemiologia , Infecção Hospitalar/microbiologia , Infecção Hospitalar/epidemiologia , Proteínas de Bactérias/genética , Enterotoxinas/genética , Masculino , Pré-Escolar , Feminino , Prevalência , Adolescente , Sequenciamento Completo do Genoma , Fenótipo , Genoma Bacteriano/genética , Lactente , Pessoa de Meia-Idade , GenômicaRESUMO
p-type Ag-N dual acceptor doped ZnO thin films with long electrical stability were deposited by DC magnetron reactive co-sputtering technique. After deposition, the films were annealed at 400 °C for one hour in a nitrogen-controlled atmosphere. The deposited films were amorphous. However, after annealing, they crystallize in the typical hexagonal wurtzite structure of ZnO. The Ag-N dual acceptors were incorporated substitutionally in the structure of zinc oxide, and achieving that; the three samples presented the p-type conductivity in the ZnO. Initial electrical properties showed a low resistivity of from 1 to 10-3 Ω·cm, Hall mobility of tens cm2/V·s, and a hole concentration from 1017 to 1019 cm-3. The electrical stability analysis reveals that the p-type conductivity of the ZnO:Ag,N films is very stable and does not revert to n-type, even after 36 months of aging. These results reveal the feasibility of using these films for applications in short-wavelength or transparent optoelectronic devices.
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Identifying edentulous victims in forensic contexts poses a significant challenge. It has been reported that having a denture to reproduce and compare Palatal Rugae (PR) patterns is crucial for identifying edentulous individuals, yet there are no validated protocols for conducting this procedure. In this study, a new method was developed and validated for plaster molding of the internal surface of upper dentures, along with a protocol involving focus-stacked photographs and reference scales. Thirty-eight edentulous subjects participated in the study, obtaining plaster models of the patients (PM), and their dentures (AM) were standardized. The AM/PM model was highlighted and photographed with ten shots in different z-focuses for each model, using standard lighting and aligning the position of the PR perpendicular to the photographic axis using tubular spirit levels and modeling clay. The images were processed using the stacking technique and analyzed by three observers through the proposed protocol using Adobe® Photoshop®. The results were analyzed based on the intra-observer and inter-observer agreement levels, with a 95% confidence interval. This study demonstrated high-precision intra-observer and inter-observer agreement (k = 1) in the matching of Palatal Rugae (PR) and maxillary morphology obtained from participants and their dentures. The protocol is simple, cost-effective, and precise. It enables standardization of the technique for obtaining plaster models, and the exposure of PR and photographic protocol minimizes the presence of artifacts in the images, thereby reducing the likelihood of errors and promoting the reproducibility of both the recording technique and the comparison of the PR.
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PURPOSE: Literature reviews outline minimally invasive approaches for abdominal diastasis in patients without skin excess. However, few surgeons are trained in endoscopic rectus sheath plication, and no simulated training programs exist for this method. This study aimed to develop and validate a synthetic simulation model for the training of skills in this approach under the Messick validity framework. METHODS: A cross-sectional study was carried out to assess the participants' previous level of laparoscopic/endoscopic skills by a questionnaire. Participants performed an endoscopic plication on the model and their performance was evaluated by one blinded observer using the global rating scale OSATS and a procedure specific checklist (PSC) scale. A 5-level Likert survey was applied to 5 experts and 4 plastic surgeons to assess Face and Content validity. RESULTS: Fifteen non-experts and 5 experts in abdominal wall endoscopic surgery were recruited. A median OSATS score [25 (range 24-25) vs 14 (range 5-22); p < 0.05 of maximum 25 points] and a median PSC score [11 (range 10-11) vs 8 (range 3-10); p < 0.05 of maximum 11 points] was significantly higher for experts compared with nonexperts. All experts agreed or strongly agreed that the model simulates a real scenario of endoscopic plication of the rectus sheath. CONCLUSION: Our simulation model met all validation criteria outlined in the Messick framework, demonstrating its ability to differentiate between experts and non-experts based on their baseline endoscopic surgical skills. This model stands as a valuable tool for evaluating skills in endoscopic rectus sheath plication.
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Competência Clínica , Reto do Abdome , Treinamento por Simulação , Humanos , Estudos Transversais , Reto do Abdome/cirurgia , Modelos Anatômicos , Endoscopia/educação , Endoscopia/métodosRESUMO
The implementation of university sustainability affects brand perceptions by conferring attributes related to commitment and reputation, especially by students. The proper management of sustainability is related to an improvement in the university brand perceived by its stakeholders, including students. For this reason, this research aims to analyse whether university sustainability positively affects brand positioning among university students. For this purpose, a theoretical and quantitative mixed-method investigation is proposed that allows the establishment of a structural model in which the relationships between the dimensions of university sustainability with the dimensions of brand positioning are evident. The empirical analysis found that some dimensions of university sustainability, such as the institutional framework, campus operations and some dimensions of the substantive functions, positively affect brand positioning in university students and generate commitment to the university from both the prestige and reputation of the brand.
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BACKGROUND: The characteristics of synovial fluid (SF) in geriatric patients differ from those in younger patients. In Mexico, epidemiologic data on the incidence of different rheumatic diseases in geriatric patients are scarce. OBJECTIVE: To describe the physical characteristics of geriatric SF and the prevalence of crystals in knee and other joint aspirates from patients with previously diagnosed joint disease. MATERIALS AND METHODS: A retrospective study was performed with a baseline of 517 SF samples between 2011 and 2023. White blood cell count was performed by Neubauer chamber and crystals were identified by polarized light microscopy. Descriptive statistical analysis was performed and prevalence was reported as a percentage. RESULTS: The mean age of the adults was 73.5±5.0 years, 54.4% were women and 45.6% were men. The mean SF volume was 6.3±9.5mL in older adults and 15.3±24.9mL in those younger than 65 years. The mean viscosity in older adults was 9.5±4.5mm and the mean leukocyte count was 7352±16,402leukocytes/mm3. Seventy percent of the older adults' SFs were referred to the laboratory for osteoarthritis (OA), with lower proportions for rheumatoid arthritis (RA) (14.6%) and gout (5.1%). Of the crystals observed in the geriatric population, 14.6% corresponded to monosodium urate crystals (CUM) and 18.9% to calcium pyrophosphate crystals (CPP). CONCLUSIONS: The characteristics of LS in older adults were smaller volume, increased viscosity, and non-inflammatory. The main diagnoses were OA, RA, and gout. The crystal content of the SF of the geriatric population corresponded mainly to CPP.
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Líquido Sinovial , Humanos , Líquido Sinovial/química , Idoso , Masculino , Feminino , Estudos Retrospectivos , Pessoa de Meia-Idade , Gota/epidemiologia , Idoso de 80 Anos ou mais , Artrite Reumatoide , México/epidemiologia , Contagem de Leucócitos , Fatores EtáriosRESUMO
BACKGROUND/AIM: Enzyme-mediated grafting of poly (gallic acid) (PGAL) and L-arginine and a-L-lysine onto PGAL produces reactive oxygen species (ROS)-suppressor multiradical molecules with low cytotoxicity, high thermostability and water solubility with cancer treatment potential. This study examined the anticancer effects of these molecules in hepatic (HepG2, ATCC HB-8065), breast (MCF7, ATCC HTB-22), and prostate (PC-3, ATCC CRL-1435 and DU 145, ATCC HTB-81) cancer cell lines, as well as in fibroblasts from healthy human skin as control cells. MATERIALS AND METHODS: PGAL was synthesized by the oxidative polymerization of the naturally abundant GA using laccase from Trametes versicolor. Insertions of amino acids L-arginine and α-L-lysine on the PGAL chain were carried out by microwave. The cells of dermal fibroblast (Fb) were obtained from primary skin cultures and isolated from skin biopsies. The cancer cells lines of hepatic (HepG2), breast (MCF7), and prostate (PC-3, DU 145) were obtained from ATCC. The viability of the cancer cells and the primary culture was obtained by the MTT assay. Proliferation was demonstrated by crystal violet assay. Cell migration was determined by Wound healing assay. Finally, cell cycle analysis was carried out with cells. RESULTS: The results show that 200 µg/ml of PGAL cultured in vitro with prostate cancer cells decreased viability, proliferation, and migration, as well as arrested cells in the G1 and S phases of the cell cycle. In contrast, the dermal fibroblasts and the hepatic line remained unaffected. The random grafting of L-Arg and a-L-Lys onto the PGAL chain also decreased the viability of prostate cancer cells. CONCLUSION: PGAL and PGAL-grafted amino acids are potential adjuvants for prostate cancer treatment, with improved physicochemical characteristics compared to GA.
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Ácido Gálico , Neoplasias da Próstata , Salicilatos , Masculino , Humanos , Ácido Gálico/farmacologia , Lisina , Trametes , Neoplasias da Próstata/patologia , Células MCF-7 , Arginina/farmacologia , Proliferação de CélulasRESUMO
Objetivo: la ferritina es importante en el almacenamiento de hierro intracelular, en una forma soluble no tóxica. Sus niveles en la gestación se la relacionan con la salud de la madre y con su descendencia. El objetivo es escribir los niveles séricos de ferritina y prevalencia de déficit de ferritina, así como los factores sociodemográficos asociados en gestantes de Colombia. Metodología: estudio transversal; análisis secundario de la Encuesta de Situación Nutricional de Colombia, 2015. Se evaluaron en 1.234 embarazadas con edades entre 12 y 48 años: sus características sociodemográficas y antropométricas, la distribución de los niveles séricos y la prevalencia de déficit de ferritina. Para estimar la asociación entre las diferentes variables sociodemográficas y los niveles séricos, o la prevalencia de déficit de ferritina, se utilizaron modelos de regresión multivariables. Resultados: la prevalencia de deficiencia de ferritina fue de 44.5 % (IC 95 % 40.1 % a 49.0 %), los niveles séricos de ferritina oscilaron entre 4 µg/L y 295,7 µg/L, con un promedio de 29.3 µg/L (IC 95 % 26,5 µg/L-32.2 µg/L). Las gestantes del segundo (OR (OR 2.19 IC 95 % 1.50 a 3.19) y tercer trimestre (OR 3.84 IC 95 % 2.68 a 5.50), aquellas que residen en la región Atlántica (OR 2.18 IC 95 % 1.25 a 3.82) y en la región Orinoquia (OR 2.41 IC 95 %1.19 a 4.88), mostraron asociación con el déficit de ferritina. Conclusión: se halló alta prevalencia en el déficit de ferritina en gestantes colombianas.
Introduction: Ferritin is important in the storage of intracellular iron, in a non-toxic soluble form. Its levels during pregnancy are related to the health of the mother and her offspring. Objective: To describe the serum ferritin levels and the prevalence of ferritin deficiency, and the associated sociodemographic factors in pregnant women in Colombia. Methodology: Cross-sectional study; secondary analysis of the Nutritional Situation Survey of Colombia, 2015. The following were evaluated in 1,234 pregnant women aged between 12 and 48 years: their sociodemographic and anthropometric characteristics, the distribution of serum levels, and the prevalence of ferritin deficiency. To estimate the association between the different sociodemographic variables and serum levels, or the prevalence of ferritin deficiency, multivariate regression models were used. Results: The prevalence of ferritin deficiency was 44.5% (95% CI 40.1% to 49.0%), serum ferritin levels ranged from 4 µg/L to 295.7 µg/L, with a average of 29.3 µg/L (95% CI 26.5 µg/L - 32.2 µg/L). Pregnant women in the second (OR (OR 2.19 95% CI 1.50 to 3.19) and third trimester (OR 3.84 95% CI 2.68 to 5.50), those residing in the Atlantic region ( OR 2.18 95% CI 1.25 to 3.82) and in the Orinoquia region (OR 2.41 95% CI 1.19 to 4.88), showed an association with ferritin deficiency. Conclusion: A high prevalence of ferritin deficiency was found in Colombian pregnant women.
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Humanos , Feminino , GravidezRESUMO
Ankylosing spondylitis (AS) is an autoinflammatory disease that affects the sacroiliac joints, causing stiffness and pain in the back. MICA is a ligand of the NKG2D receptor, and an increase in its expression affects the immune response in various diseases. NLRP3 is a multiprotein complex that promotes the release of IL-1ß, but its role in AS has been minimally explored. The objective of this study was to analyze the association and interaction of polymorphic variants of the MICA and NLRP3 genes in patients with AS. In this case-control study, patients with AS were included and compared with healthy controls of Mexican origin. The polymorphisms rs4349859 and rs116488202 of MICA and rs3806268 and rs10754558 of NLRP3 were genotyped using TaqMan probes. Associations were determined using logistic regression models, while interactions were analyzed by the multifactorial dimensionality reduction (MDR) method. A P value < 0.05 was considered statistically significant. The minor allele of rs4349859 (A) and rs116488202 (T) of MICA polymorphisms showed risk associations with AS (OR = 9.22, 95% CI = 4.26-20.0, P < 0.001; OR = 9.36, 95% CI = 4.17-21.0, P < 0.001), while the minor allele of the rs3806268 (A) polymorphism of NLRP3 was associated with protection (OR = 0.55, 95% CI = 0.33-0.91, P = 0.019). MDR analysis revealed synergistic interactions between the MICA and NLRP3 polymorphisms (P = 0.012). In addition, high- and low-risk genotypes were identified among these variants. The study findings suggest that the MICA rs4349859 A allele and rs116488202 T allele are associated with AS risk. An interaction between MICA and NLRP3 was observed which could increase the genetic risk in AS.
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Espondilite Anquilosante , Humanos , Espondilite Anquilosante/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Estudos de Casos e Controles , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , GenótipoRESUMO
CagY is the largest and most complex protein from Helicobacter pylori's (Hp) type IV secretion system (T4SS), playing a critical role in the modulation of gastric inflammation and risk for gastric cancer. CagY spans from the inner to the outer membrane, forming a channel through which Hp molecules are injected into human gastric cells. Yet, a tridimensional structure has been reported for only short segments of the protein. This intricate protein was modeled using different approaches, including homology modeling, ab initio, and deep learning techniques. The challengingly long middle repeat region (MRR) was modeled using deep learning and optimized using equilibrium molecular dynamics. The previously modeled segments were assembled into a 1595 aa chain and a 14-chain CagY multimer structure was assembled by structural alignment. The final structure correlated with published structures and allowed to show how the multimer may form the T4SS channel through which CagA and other molecules are translocated to gastric cells. The model confirmed that MRR, the most polymorphic and complex region of CagY, presents numerous cysteine residues forming disulfide bonds that stabilize the protein and suggest this domain may function as a contractile region playing an essential role in the modulating activity of CagY on tissue inflammation.