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1.
Diagn Microbiol Infect Dis ; 110(2): 116428, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39094238

RESUMEN

Acinetobacter baumannii poses a significant health threat because of its frequent implications in hospital outbreaks and multidrug resistance (MDR). Here, we studied four A. baumannii isolates recovered during a hospital outbreak of severe or fatal cases to elucidate their diversity and factors contributing to their increased virulence and antibiotic resistance. The isolates were identified using MALDI-ToF and characterized using comparative genomics, PCR, and antimicrobial susceptibility tests. They were classified as ST126 and exhibited fewer than five chromosomal single-nucleotide variants and the same extrachromosomal content, indicating that they are a single strain (A. baumannii AB01). A. baumannii AB01 showed an MDR phenotype that could be linked to the carriage of parC and gyrA mutations, efflux transporters, aminoglycoside resistance genes, a class C beta-lactamase, and three carbapenemases, some of which are encoded on a 72 kb plasmid. ST126 is infrequent and has not been reported in Latin America, and our genomic data indicate a plausible origin for A. baumannii AB01 within the Pan Pacific region.


Asunto(s)
Infecciones por Acinetobacter , Acinetobacter baumannii , Proteínas Bacterianas , Brotes de Enfermedades , Farmacorresistencia Bacteriana Múltiple , Pruebas de Sensibilidad Microbiana , Plásmidos , beta-Lactamasas , beta-Lactamasas/genética , Humanos , Infecciones por Acinetobacter/microbiología , Infecciones por Acinetobacter/epidemiología , Acinetobacter baumannii/genética , Acinetobacter baumannii/efectos de los fármacos , Acinetobacter baumannii/enzimología , Acinetobacter baumannii/aislamiento & purificación , Farmacorresistencia Bacteriana Múltiple/genética , Plásmidos/genética , Proteínas Bacterianas/genética , Antibacterianos/farmacología , Masculino , Femenino , Infección Hospitalaria/microbiología , Infección Hospitalaria/epidemiología , Persona de Mediana Edad
2.
Biochim Biophys Acta Mol Basis Dis ; 1870(6): 167256, 2024 08.
Artículo en Inglés | MEDLINE | ID: mdl-38782303

RESUMEN

The primary cilium, hereafter cilium, is an antenna-like organelle that modulates intracellular responses, including autophagy, a lysosomal degradation process essential for cell homeostasis. Dysfunction of the cilium is associated with impairment of autophagy and diseases known as "ciliopathies". The discovery of autophagy-related proteins at the base of the cilium suggests its potential role in coordinating autophagy initiation in response to physiopathological stimuli. One of these proteins, beclin-1 (BECN1), it which is necessary for autophagosome biogenesis. Additionally, polycystin-2 (PKD2), a calcium channel enriched at the cilium, is required and sufficient to induce autophagy in renal and cancer cells. We previously demonstrated that PKD2 and BECN1 form a protein complex at the endoplasmic reticulum in non-ciliated cells, where it initiates autophagy, but whether this protein complex is present at the cilium remains unknown. Anorexigenic pro-opiomelanocortin (POMC) neurons are ciliated cells that require autophagy to maintain intracellular homeostasis. POMC neurons are sensitive to metabolic changes, modulating signaling pathways crucial for controlling food intake. Exposure to the saturated fatty acid palmitic acid (PA) reduces ciliogenesis and inhibits autophagy in these cells. Here, we show that PKD2 and BECN1 form a protein complex in N43/5 cells, an in vitro model of POMC neurons, and that both PKD2 and BECN1 locate at the cilium. In addition, our data show that the cilium is required for PKD2-BECN1 protein complex formation and that PA disrupts the PKD2-BECN1 complex, suppressing autophagy. Our findings provide new insights into the mechanisms by which the cilium controls autophagy in hypothalamic neuronal cells.


Asunto(s)
Autofagia , Beclina-1 , Cilios , Hipotálamo , Neuronas , Canales Catiónicos TRPP , Animales , Ratones , Beclina-1/metabolismo , Cilios/metabolismo , Hipotálamo/metabolismo , Hipotálamo/citología , Neuronas/metabolismo , Canales Catiónicos TRPP/metabolismo , Canales Catiónicos TRPP/genética
3.
Paediatr Anaesth ; 34(9): 858-865, 2024 09.
Artículo en Inglés | MEDLINE | ID: mdl-38619275

RESUMEN

BACKGROUND: Latin America comprises an extensive and diverse territory composed of 33 countries in the Caribbean, Central, and South America where Romance languages-languages derived from Latin are predominantly spoken. Economic disparities exist, with inequitable access to pediatric surgical care. The Latin American Surgical Outcomes Study in Pediatrics (LASOS-Peds), a multi-national collaboration, will determine safety of pediatric anesthesia and perioperative care. OBJECTIVE: Below, we provide a descriptive initiative to share how pediatric anesthesia in Brazil, Chile, and Mexico operate. Theses descriptions do not represent all of Latin America. DESCRIPTIONS AND CONCLUSIONS: Brazil an upper middle-income country, population 203 million, has a public system insufficiently resourced and a private system, resulting in inequitable safety and accessibility. Surgical complications constitute the third leading cause of mortality. Anesthesiology residency is 3 years, with required rotations in pediatric anesthesia; five hospitals offer pediatric anesthesia fellowships. Anesthesiology is a physician-only practice. A Pediatric Anesthesia Committee within the Brazilian Society of Anesthesiology offers education through seasonal courses and workshops including pediatric advanced life support. Chile is a high-income country, population 19.5 million, the majority cared for in the public system, the remainder in university, private, or military systems. Government efforts have gradually corrected the long-standing anesthesiology shortage: twenty 3-year residency programs prepare graduates for routine pediatric cases. The Chilean Society of Anesthesiology runs a 1-month program for general anesthesiologists to enhance pediatric anesthesia skills. Pediatric anesthesia fellowship training occurs in Europe, USA, and Australia, or in two 2-year Chilean university programs. Public health policies have increased the medical and surgical pediatric specialists and general anesthesiologists, but not pediatric anesthesiologists, which creates safety concerns for neonates, infants, and medically complex. Chile needs more pediatric anesthesia fellowship programs. Mexico, an upper middle-income country, with a population of about 126 million, has a five-sector healthcare system: public, social security for union workers, state for public employees, armed forces for the military, and a private "self-pay." There are inequities in safety and accessibility for children. Pediatric Anesthesiology fellowship is 2 years, after 3 years residency. A shortage of pediatric anesthesiologists limits accessibility and safety for surgical care, driven by added training at low salary and hospital under appreciation. The Mexican Society of Pediatric Anesthesiology conducts refresher courses, workshops, and case conferences. Insufficient resources and culture limits research.


Asunto(s)
Anestesiología , Pediatría , Humanos , Chile , Anestesiología/educación , Pediatría/educación , Niño , México , Brasil , Internado y Residencia
4.
Oncol Lett ; 25(6): 223, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37153033

RESUMEN

Glioblastomas are the most aggressive and common primary brain tumors in adults. Glioblastoma cells have a great capacity to migrate and invade the brain parenchyma, often reaching the contralateral hemisphere. Progesterone (P4) and its metabolite, allopregnanolone (3α-THP), promote the migration and invasion of human glioblastoma-derived cells. P4 induces migration in glioblastoma cells by the activation of the proto-oncogene tyrosine-protein kinase Src (cSrc) and focal adhesion kinase (Fak). In breast cancer cells, cSrc and Fak promote invasion by increasing the expression and activation of extracellular matrix metalloproteinases (MMPs). However, the mechanism of action by which P4 and 3a-THP promote invasion in glioblastoma cells remains unclear. The effects of P4 and 3α-THP on the protein expression levels of MMP-2 and -9 and the participation of cSrc in progestin effects in U251 and U87 human glioblastoma-derived cells were evaluated. It was determined by western blotting that the P4 increased the protein expression level of MMP-9 in U251 and U87 cells, and 3α-THP increased the protein expression level of MMP-9 in U87 cells. None of these progestins modified MMP-2 protein expression levels. The increase in MMP-9 expression was reduced when the intracellular progesterone receptor and cSrc expression were blocked with small interfering RNAs. Cell invasion induced by P4 and 3α-THP was also blocked by inhibiting cSrc activity with PP2 or by cSrc gene silencing. These results suggest that P4 and its metabolite 3α-THP induce the invasion of glioblastoma cells by increasing MMP-9 expression through the cSrc kinase family. The results of this study provide information of interest in the context of targeted therapies against molecular pathways involved in glioblastoma invasion.

5.
Diagnostics (Basel) ; 12(11)2022 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-36428856

RESUMEN

Midazolam is a drug that is metabolized by cytochrome P450 (CYP450) enzymes, particularly CYP3A4 and CYP3A5. The present study aimed to determine the sex and age influence on association of CYP450 polymorphism with midazolam levels in critically ill children. Seventy-two DNA samples were genotyped by real-time PCR. Children ≤ five years of age who carry the rs776746 (T) allele in CYP3A5 gene were associated with lower plasma midazolam levels. The concentration median in patients was 0.0 ng/mL, while in patients with the normal (C) allele, it was 438.17 ng/mL (Q25 135.75-Q75 580.24), p = 0.005. The midazolam plasmatic concentration in female patients with the minor (T) allele was 0.0 ng/mL (Q250.00-Q75204.3), while in patients with the normal (C) allele median it was 459.0 ng/mL (Q25296.9-Q75789.7), p = 0.002. Analysis of the dominant model for the rs2740574 variant in CYP3A4 revealed a median of 0.38 L/kg (Q250.02-Q751.5) for the volume of distribution parameter in female patients with the normal T allele, while female patients with the minor C allele showed a median of 18.1 L/kg (Q257.5-Q7528.7) p = 0.02. Our results suggest an altered midazolam metabolism due to the presence the allelic rs2740574 variants of CYP3A4 and rs776746 of CYP3A5, and also the strong influence of age and sex.

6.
Oncol Lett ; 24(5): 397, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36276488

RESUMEN

Glioblastoma (GB) is the most frequent primary brain tumor with a very poor prognosis. Sex hormones are crucial players in the development of GBs. 17 ß-estradiol (E2) signaling is involved through its corresponding intracellular receptors [estrogen receptor α (ERα) and ß (ERß)] in GB cell proliferation and progression. E2 activates G-protein coupled estrogen receptor (GPER), leading to rapidly occurring effects, independently of gene transcription. GPER activation is involved in tumor progression in various cancer types. Currently, available data concerning the occurrence and role of GPER in GB are very limited. In the present study, it was observed that GPER was expressed in human brain tumor cell lines [U251 (astrocytoma-derived cell line), U87, LN229 and T98 (glioblastoma-derived cell line)]. Immunofluorescence assays revealed that GPER localizes in the plasma membrane, cytoplasm and nucleus. An in silico analysis identified two potential E2 response elements in the promoter region of the GPER gene. E2 increased GPER expression in the U251, U87 and LN229 cell lines. Molecular modeling data derived from in silico analysis predicted the three-dimensional conformation of GPER, and docking analysis identified potential binding sites of E2 and its specific agonist, G1. Taken together, these results indicate that GPER may be differentially expressed in human GB cell lines with E2 possibly upregulating GPER expression. The present study raises further questions about the implications of GPER-mediated E2 signaling in the biology of GBs.

7.
Cells ; 11(6)2022 03 08.
Artículo en Inglés | MEDLINE | ID: mdl-35326371

RESUMEN

The intake of food with high levels of saturated fatty acids (SatFAs) is associated with the development of obesity and insulin resistance. SatFAs, such as palmitic (PA) and stearic (SA) acids, have been shown to accumulate in the hypothalamus, causing several pathological consequences. Autophagy is a lysosomal-degrading pathway that can be divided into macroautophagy, microautophagy, and chaperone-mediated autophagy (CMA). Previous studies showed that PA impairs macroautophagy function and insulin response in hypothalamic proopiomelanocortin (POMC) neurons. Here, we show in vitro that the exposure of POMC neurons to PA or SA also inhibits CMA, possibly by decreasing the total and lysosomal LAMP2A protein levels. Proteomics of lysosomes from PA- and SA-treated cells showed that the inhibition of CMA could impact vesicle formation and trafficking, mitochondrial components, and insulin response, among others. Finally, we show that CMA activity is important for regulating the insulin response in POMC hypothalamic neurons. These in vitro results demonstrate that CMA is inhibited by PA and SA in POMC-like neurons, giving an overview of the CMA-dependent cellular pathways that could be affected by such inhibition and opening a door for in vivo studies of CMA in the context of the hypothalamus and obesity.


Asunto(s)
Autofagia Mediada por Chaperones , Humanos , Insulina/metabolismo , Neuronas/metabolismo , Obesidad/metabolismo , Proopiomelanocortina/metabolismo , Ácidos Esteáricos/metabolismo , Ácidos Esteáricos/farmacología
8.
Front Endocrinol (Lausanne) ; 13: 703733, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35197928

RESUMEN

Glioblastomas (GBM) are the most frequent and aggressive brain tumors. 17ß-estradiol (E2) increases proliferation, migration, and invasion of human GBM cells; however underlying mechanisms are no fully understood. Zeste 2 Enhancer Homologous enzyme (EZH2) is a methyltransferase part of Polycomb 2 repressor complex (PRC2). In GBM, EZH2 is overexpressed and involved in the cell cycle, migration, and invasion processes. We studied the role of EZH2 in the pro-oncogenic actions of E2 in human GBM cells. EZH2 gene silencing and pharmacological inhibition of EZH2 blocked proliferation, migration, and invasion of GBM cells induced by E2. We identified in silico additional putative estrogen response elements (EREs) at the EZH2 promoter, but E2 did not modify EZH2 expression. In silico analysis also revealed that among human GBM samples, EZH2 expression was homogeneous; in contrast, the heterogeneous expression of estrogen receptors (ERs) allowed the classification of the samples into groups. Even in the GBM cluster with high expression of ERs and those of their target genes, the expression of PCR2 target genes did not change. Overall, our data suggest that in GBM cells, pro-oncogenic actions of E2 are mediated by EZH2, without changes in EZH2 expression and by mechanisms that appear to be unrelated to the transcriptional activity of ERs.


Asunto(s)
Proteína Potenciadora del Homólogo Zeste 2 , Glioblastoma , Movimiento Celular/genética , Proliferación Celular , Proteína Potenciadora del Homólogo Zeste 2/genética , Proteína Potenciadora del Homólogo Zeste 2/metabolismo , Estradiol/farmacología , Glioblastoma/genética , Glioblastoma/metabolismo , Glioblastoma/patología , Humanos
9.
Rev. argent. microbiol ; Rev. argent. microbiol;52(4): 101-110, dic. 2020. graf
Artículo en Inglés | LILACS | ID: biblio-1340925

RESUMEN

Abstract This work aimed to investigate the prevalence of Trichinella infection in horses (Equus ferus caballus) handled by rural slaughterhouses across five distinctive socioeconomic regions in Mexico. Serum samples were obtained by non-probabilistic convenience sampling in the Eastern, Southern Central and Western regions (100 samples of each). Additionally, muscle tissue samples were collected from the East (n = 45), Southeastern (n = 88), Southern Central (n = 39) and Southwestern (n = 11) regions. Antibodies were determined by Western blot and the muscle tissue was examined by artificial digestion. A global antibody prevalence of 2% was obtained. Regionally, a prevalence of 5% was observed in the East and 1% in the Southern Central region. No antibodies were detected in the West region and no larvae were found in the muscle tissue samples. These findings support the low presence of Trichinella in Mexican horses, which can positively impact the Mexican horse meat trade.


Resumen Se investigó la prevalencia de Trichinella en caballos (Equus ferus caballus) demataderos rurales en cinco regiones socioeconómicas de México. Los sueros se obtuvieron por Trichinella muestreo de conveniencia no probabilístico en las regiones Este, Centrosur y Oeste (100 muestras de cada una). Además se colectaron muestras de tejido muscular de animales de las regionesEste (n = 45), Centro Sur (n = 39), Sudeste (n = 88) y Sudoeste (n = 11). Los anticuerpos se determinaron por Western blot y el tejido muscular se examinó por digestión artificial. Se obtuvo una prevalencia global de anticuerpos del 2%. A nivel regional se observó una prevalencia del 5% enel Este y del 1% en el Centrosur. No se detectaron anticuerpos en el Oeste y no se encontraron larvas en el tejido muscular. Los datos respaldan la baja presencia de Trichinella en caballos mexicanos, lo que puede impactar positivamente en su comercio.


Asunto(s)
Animales , Trichinella , Triquinelosis , Enfermedades de los Caballos , Factores Socioeconómicos , Triquinelosis/veterinaria , Triquinelosis/epidemiología , Mataderos , Enfermedades de los Caballos/epidemiología , Caballos , Carne , México/epidemiología
10.
Rev Argent Microbiol ; 52(4): 288-292, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32507326

RESUMEN

This work aimed to investigate the prevalence of Trichinella infection in horses (Equus ferus caballus) handled by rural slaughterhouses across five distinctive socioeconomic regions in Mexico. Serum samples were obtained by non-probabilistic convenience sampling in the Eastern, Southern Central and Western regions (100 samples of each). Additionally, muscle tissue samples were collected from the East (n=45), Southeastern (n=88), Southern Central (n=39) and Southwestern (n=11) regions. Antibodies were determined by Western blot and the muscle tissue was examined by artificial digestion. A global antibody prevalence of 2% was obtained. Regionally, a prevalence of 5% was observed in the East and 1% in the Southern Central region. No antibodies were detected in the West region and no larvae were found in the muscle tissue samples. These findings support the low presence of Trichinella in Mexican horses, which can positively impact the Mexican horse meat trade.


Asunto(s)
Enfermedades de los Caballos , Trichinella , Triquinelosis , Mataderos , Animales , Enfermedades de los Caballos/epidemiología , Caballos , Carne , México/epidemiología , Factores Socioeconómicos , Triquinelosis/epidemiología , Triquinelosis/veterinaria
11.
12.
Materials (Basel) ; 12(21)2019 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-31671868

RESUMEN

Modern concrete infrastructure requires structural components with higher mechanical strength and greater durability. A solution is the addition of nanomaterials to cement-based materials, which can enhance their mechanical properties. Some such nanomaterials include nano-silica (nano-SiO2), nano-alumina (nano-Al2O3), nano-ferric oxide (nano-Fe2O3), nano-titanium oxide (nano-TiO2), carbon nanotubes (CNTs), graphene and graphene oxide. These nanomaterials can be added to cement with other reinforcement materials such as steel fibers, glass, rice hull powder and fly ash. Optimal dosages of these materials can improve the compressive, tensile and flexural strength of cement-based materials, as well as their water absorption and workability. The use of these nanomaterials can enhance the performance and life cycle of concrete infrastructures. This review presents recent researches about the main effects on performance of cement-based composites caused by the incorporation of nanomaterials. The nanomaterials could decrease the cement porosity, generating a denser interfacial transition zone. In addition, nanomaterials reinforced cement can allow the construction of high-strength concrete structures with greater durability, which will decrease the maintenance requirements or early replacement. Also, the incorporation of nano-TiO2 and CNTs in cementitious matrices can provide concrete structures with self-cleaning and self-sensing abilities. These advantages could help in the photocatalytic decomposition of pollutants and structural health monitoring of the concrete structures. The nanomaterials have a great potential for applications in smart infrastructure based on high-strength concrete structures.

13.
J Agric Food Chem ; 61(44): 10439-46, 2013 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-24164234

RESUMEN

Low-temperature conditioning of garlic "seed" cloves accelerated the development of the crop cycle, decreased plant growth, and increased the synthesis of phenolic compounds and anthocyanins in the outer scale leaves of the bulbs at harvest time, leading to 3-fold content increase compared with those conditioned at room temperature. Cold conditioning of "seed" cloves also altered the anthocyanin profile during bulb development and at harvest. Two new anthocyanins are reported for the first time in garlic. The high phenolics and anthocyanin contents in bulbs of plants generated from "seed" cloves conditioned at 5 °C for 5 weeks were preceded by overexpression of some putative genes of the phenolic metabolism [6-fold for phenylalanine ammonia lyase (PAL)] and anthocyanin synthesis [1-fold for UDP-sugar:flavonoid 3-O-glycosyltransferase (UFGT)] compared with those conditioned at room temperature.


Asunto(s)
Antocianinas/química , Ajo/crecimiento & desarrollo , Fenoles/metabolismo , Proteínas de Plantas/genética , Antocianinas/biosíntesis , Frío , Ajo/química , Ajo/genética , Ajo/metabolismo , Regulación del Desarrollo de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Fenoles/química , Proteínas de Plantas/metabolismo , Semillas/química , Semillas/enzimología , Semillas/genética , Semillas/crecimiento & desarrollo , Temperatura
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