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1.
Infect Genet Evol ; : 105644, 2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-39038632

RESUMO

IncQ-type plasmids have become important vectors in the dissemination of blaGES among different bacterial genera and species from different environments around the world, and studies estimating the occurrence of Guiana extended-spectrum (GES)-type ß-lactamases are gaining prominence. We analyzed the genetic aspects of two IncQ1 plasmids harboring different blaGES variants from human and environmental sources. The blaGES variants were identified using polymerase chain reaction (PCR) in Aeromonas veronii isolated from hospital effluent and Klebsiella variicola isolated from a rectal swab of a patient admitted to the cardiovascular intensive care unit in a different hospital. Antimicrobial-susceptibility testing and transformation experiments were performed for phenotypic analysis. Whole-genome sequencing was performed using Illumina and Oxford Nanopore platforms. The comparative analysis of plasmids was performed using BLASTn, and the IncQ1 plasmids showed a high identity and similar size. A. veronii harbored blaGES-7 in a class 1 integron (In2061), recently described by our group, and K. variicola carried blaGES-5 in the known class 1 integron. Both integrons showed a fused gene cassette that encodes resistance to aminoglycosides and fluoroquinolones, with an IS6100 truncating the 3'-conserved segment. The fused genes are transcribed together, although the attC site is disrupted. These gene cassettes can no longer be mobilized. This study revealed a mobilome that may contribute to the dissemination of GES-type ß-lactamases in Brazil. Class 1 integrons are hot spots for bacterial evolution, and their insertion into small IncQ-like plasmids displayed successful recombination, allowing the spread of blaGES variants in various environments. Therefore, they can become prevalent across clinically relevant pathogens.

2.
Plants (Basel) ; 13(11)2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38891346

RESUMO

Khat leaves, indigenous to eastern Africa, have been chewed for centuries for their stimulant effects, attributed to alkaloids such as cathinone and cathine. Although associated with gastric disorders like gastritis and gastro-oesophageal reflux disease, the underlying molecular mechanisms remain unclear. This study aimed to examine the morpho-anatomy of khat leaves using light microscopy and histochemistry and to assess the effects of leaf extracts and alkaloids on human gastric epithelial cells (GES-1). The study identified specific cells in the palisade-spongy transition zone as storage sites for psychoactive alkaloids. Leaf extracts were prepared by mimicking the chewing process, including a prolonged salivary phase followed by a gastric phase. Cytotoxicity and cell viability were evaluated using LDH and MTT assays, respectively. Additionally, the impact on IL-8 secretion, a key chemokine in gastric inflammation, was analysed under normal and TNF-α-stimulated conditions. The results showed no increase in cytotoxicity up to 250 µg/mL. However, there was a significant decrease in cell metabolism and a reduction in both basal and TNF-α-induced IL-8 secretion, but cathinone and cathine were inactive. These findings suggest that khat may not directly cause the gastric issues reported in the literature, which would rather be attributed to other confounding factors, highlighting the need for further research to clarify its biological impacts.

3.
ACS Appl Mater Interfaces ; 16(26): 33740-33751, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38907704

RESUMO

A two-dimensional (2D) broken-gap (type-III) p-n heterojunction has a unique charge transport mechanism because of nonoverlapping energy bands. In light of this, type-III band alignment can be used in tunneling field-effect transistors (TFETs) and Esaki diodes with tunable operation and low consumption by highlighting the advantages of tunneling mechanisms. In recent years, 2D tunneling photodiodes have gradually attracted attention for novel optoelectronic performance with a combination of strong light-matter interaction and tunable band alignment. However, an in-depth understanding of the tunneling mechanisms should be further investigated, especially for developing electronic and optoelectronic applications. Here, we report a type-III tunneling photodiode based on a 2D multilayered p-GeS/n+-SnSe2 heterostructure, which is first fabricated by the mechanical exfoliation and dry transfer method. Through the Simmons approximation, its various tunneling transport mechanisms dependent on bias and light are demonstrated as the origin of excellent bidirectional photoresponse performance. Moreover, compared to the traditional p-n photodiode, the device enables bidirectional photoresponse capability, including maximum responsivity values of 43 and 8.7 A/W at Vds = 1 and -1 V, respectively, with distinctive photoactive regions from the scanning photocurrent mapping. Noticeably, benefiting from the in-plane anisotropic structure of GeS, the device exhibits an enhanced photocurrent anisotropic ratio of 9, driven by the broader depletion region at Vds = -3 V under 635 nm irradiation. Above all, the results suggest that our designed architecture can be potentially applied to CMOS imaging sensors and polarization-sensitive photodetectors.

4.
Int J Antimicrob Agents ; 64(2): 107257, 2024 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-38914141

RESUMO

OBJECTIVES: To describe the in vivo emergence of ceftazidime-avibactam resistance in GES-type carbapenemases and to characterize an unusual outbreak of GES-6-producing Serratia marcescens during the COVID-19 pandemic in Spain. METHODS: Retrospective study to describe a GES-CPSM outbreak based on whole genome sequencing and antimicrobial susceptibility testing (AST). Transferability of blaGES-carrying plasmid was assessed by conjugation experiments. RESULTS: In December 2020, we identified a cluster of S. marcescens harbouring blaGES-6 involving 9 patients. Whole-genome sequence analysis revealed a clonal relationship (≤3 SNPs) between the first isolates identified in each of the evolved patients and environmental samples with GES-CPSM detection. Plasmid analysis showed that the blaGES-6 gene was located in an IncQ3-type plasmid. Triparental mating experiments using a helper plasmid demonstrated mobilization of the blaGES-6-carrying plasmid. Our results also demonstrate within-host evolution in S. marcescens isolates, leading to a transition from blaGES-6 to the new blaGES-55, caused by the P162S mutation, in a subsequent infection in one of the affected patients. In blaGES-55 we identified emergence of ceftazidime-avibactam resistance along with an increase of carbapenems susceptibility. This patient had been treated with a 14-day course of ceftazidime-avibactam. AST of the transformants bearing blaGES-6 and blaGES-55 plasmids, confirmed susceptibility variation affecting ceftazidime-avibactam and carbapenems. CONCLUSIONS: We report an unusual outbreak of GES-6 whose incidence is becoming increasing. Transition from GES-6 to GES-55 may readily occur in vivo leading to ceftazidime-avibactam resistance, which brings to the fore the critical need for developing more accurate diagnosis tools for detection of GES ß-lactamases and optimise the use of antimicrobials.

5.
Mar Pollut Bull ; 205: 116647, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38941806

RESUMO

The loggerhead sea turtle Caretta caretta has been chosen as bioindicator to monitor the amount of litter ingested by marine animals within the European Marine Strategy Framework Directive and the Barcelona Regional Sea Convention. European Member States and Contracting Parties are committed to achieve the Good Environmental Status (GES), which is reached when the quantity of ingested litter does not adversely affect the health of the species concerned. Although the monitoring strategy has been outlined for more than a decade, to date no threshold values have been adopted to verify GES achievement. After five years of extensive monitoring along the Italian coasts, this study evaluates the suitability of five different GES scenarios and proposes a new threshold value (i.e., "there should be less than 33% of sea turtles having more than 0.05 g of ingested plastic in the GI") for its implementation in the European seas and the Mediterranean basin.


Assuntos
Monitoramento Ambiental , Tartarugas , Animais , Tartarugas/fisiologia , Monitoramento Ambiental/métodos , Itália , Plásticos , Poluentes Químicos da Água/análise
6.
Zhongguo Zhong Yao Za Zhi ; 49(8): 2230-2246, 2024 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-38812238

RESUMO

Total triterpenoids from the fruits of Chaenomeles speciosa(TCS) are active components in the prevention and treatment of gastric mucosal damage, which have potential anti-aging effects. However, it is still unclear whether TCS can improve gastric aging, especially its molecular mechanism against gastric aging. On this basis, this study explored the effect and mechanism of TCS on senescent GES-1 cells induced by D-galactose(D-gal) to provide scientific data for the clinical use of TCS to prevent gastric aging. GES-1 cells cultured in vitro and those transfected with overexpression GLS1(GLS1-OE) plasmid of glutaminase 1(GLS1) were induced to aging by D-gal, and then TCS and or GLS1 inhibitor bis-2-(5-phenylacetamido-1,3,4-thiadiazol-2-yl) ethyl sulfide(BPTES) were given. Cell survival rate, positive rate of ß-galactosidase(SA-ß-gal) staining, mitochondrial membrane potential(MMP), and apoptosis were investigated. GLS1 activity, levels of glutamine(Gln), glutamate(Glu), α-ketoglutarate(α-KG), urea, and ammonia in supernatant and cells were detected by enzyme-linked immunosorbent assay(ELISA) and colorimetric methods. The mRNA and protein expressions of GLS1 and the related genes of the mitochondrial apoptosis signaling pathway were measured by real-time fluorescence quantitative PCR and Western blot. The results manifested that compared with the D-gal model group and GLS1-OE D-gal model group, TCS significantly decreased the SA-ß-gal staining positive cell rate and MMP of D-gal-induced senescent GES-1 cells and GLS1-OE senescent GES-1 cells, inhibited the survival of senescent cells, and promoted their apoptosis(P<0.01). It decreased the activity of GLS1 and the content of Gln, Glu, α-KG, urea, and ammonia in supernatant and cell(P<0.01), reduced the concentration of cytochrome C(Cyto C) in mitochondria and the mRNA and protein expressions of GLS1 and proliferating nuclear antigen in cells(P<0.01). The mRNA expression of Bcl-2 and Bcl-xl, the protein expression of pro-caspase-9 and pro-caspase-3, and the ratio of Bcl-2/Bax and Bcl-xl/Bad in cells were decreased(P<0.01). Cyto C concentration in the cytoplasm, the mRNA expressions of Bax, Bad, apoptosis protease activating factor 1(Apaf-1), and protein expressions of cleaved-caspase-9, cleaved-caspase-3, cleaved-PARP-1 were increased(P<0.01). The aforementioned results indicate that TCS can counteract the senescent GES-1 cells induced by D-gal, and its mechanism may be closely related to suppressing the Gln/GLS1/α-KG metabolic axis, activating the mitochondrial apoptosis pathway, and thereby accelerating the apoptosis of the senescent cells and eliminating senescent cells.


Assuntos
Apoptose , Frutas , Galactose , Glutaminase , Glutamina , Mitocôndrias , Transdução de Sinais , Triterpenos , Apoptose/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Triterpenos/farmacologia , Triterpenos/química , Humanos , Transdução de Sinais/efeitos dos fármacos , Linhagem Celular , Frutas/química , Glutamina/farmacologia , Glutamina/metabolismo , Glutaminase/metabolismo , Glutaminase/genética , Senescência Celular/efeitos dos fármacos , Ácidos Cetoglutáricos/farmacologia , Ácidos Cetoglutáricos/metabolismo
7.
Antioxidants (Basel) ; 13(5)2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38790723

RESUMO

Gastric diseases represent a significant global public health challenge, characterized by molecular dysregulation in redox homeostasis and heightened oxidative stress. Although prior preclinical studies have demonstrated the cytoprotective antioxidant effects of alginate oligosaccharides (AOSs) through the Nrf2 pathway, whether such mechanisms apply to gastric diseases remains unclear. In this study, we used the GES-1 gastric cell line exposed to hydrogen peroxide (H2O2) as a damage model to investigate the impact of AOS on cell viability and its associated mechanisms. Our results revealed that pre-incubation with AOS for either 4 h or 24 h significantly improved the viability of GES-1 cells exposed to H2O2. In addition, AOS reduced the intracellular ROS levels, activating the Nrf2 signaling pathway, with increased Nrf2 protein and mRNA expression and a significant upregulation of the target genes HO-1 and NQO1. The activation of Nrf2 was correlated with decreased Keap1 protein expression and an increased level of the autophagy protein p62/SQSTM1, suggesting the activation of Nrf2 through a noncanonical pathway. This study suggests that AOS is a potential treatment for protecting gastric epithelial cells from oxidative stress by activating the p62/SQSTM1-Keap1-Nrf2 axis and laying the foundation for future investigations about its specific therapeutic mechanisms.

8.
Adv Mater ; 36(28): e2313721, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38669677

RESUMO

Germanium-based monochalcogenides (i.e., GeS and GeSe) with desirable properties are promising candidates for the development of next-generation optoelectronic devices. However, they are still stuck with challenges, such as relatively fixed electronic band structure, unconfigurable optoelectronic characteristics, and difficulty in achieving free-standing growth. Herein, it is demonstrated that two-dimensional (2D) free-standing GeS1-xSex (0 ≤ x ≤ 1) nanoplates can be grown by low-pressure rapid physical vapor deposition (LPRPVD), fulfilling a continuously composition-tunable optical bandgap and electronic band structure. By leveraging the synergistic effect of composition-dependent modulation and free-standing growth, GeS1-xSex-based optoelectronic devices exhibit significantly configurable hole mobility from 6.22 × 10-4 to 1.24 cm2V-1s⁻1 and tunable responsivity from 8.6 to 311 A W-1 (635 nm), as x varies from 0 to 1. Furthermore, the polarimetric sensitivity can be tailored from 4.3 (GeS0.29Se0.71) to 1.8 (GeSe) benefiting from alloy engineering. Finally, the tailored imaging capability is also demonstrated to show the application potential of GeS1-xSex alloy nanoplates. This work broadens the functionality of conventional binary materials and motivates the development of tailored polarimetric optoelectronic devices.

9.
ACS Appl Mater Interfaces ; 16(13): 16445-16452, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38528798

RESUMO

Zero-valent intercalation of atomic metals into the van der Waals gap of layered materials can be used to tune their electronic, optical, thermal, and mechanical properties. Here, we report the impact of intercalating ∼3 atm percent of zero-valent copper into germanium sulfide (GeS). Advanced many-body calculations predict that copper introduces quasi-localized intermediate band states, and time-resolved THz spectroscopy studies demonstrate that those states have prominent effects on the photoconductivity of GeS. Cu-intercalated GeS exhibits a faster rise of transient photoconductivity and a shorter lifetime of optically injected carriers following near-gap excitation with 800 nm pulses. At the same time, Cu intercalation improves free carrier mobility from 1100 to 1300 cm2 V-1 s-1, which we attribute to the damping of acoustic phonons observed in Brillouin scattering and consequent reduction of phonon scattering.

10.
Indian J Endocrinol Metab ; 28(1): 35-42, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38533281

RESUMO

Introduction: Gastrointestinal neuropathies are frequently found in diabetic patients. The pathogenesis of diabetic gastroparesis (DG) is multifactorial. The usual treatment for DG includes dietary modifications, prokinetic and antiemetic agents. There is increasing demand for more effective medicines to treat DG. The current study was conducted on the Pistacia lentiscus stem extract to add to the armamentarium of DG treatment and to find the efficacy of P. lentiscus plant extract (mastic gum) in comparison to levosulpiride in DG for improvement in gastroparesis symptoms and gastric emptying scintigraphy (GES) in a single centric double-blind non-inferiority randomised control trial. Methods: Thirty-eight individuals were recruited and equally randomised into two study groups based on Gastroparesis Cardinal Symptom Index (GCSI) score and TC99 Radionuclide GES, mastic gum group and levosulpiride group. Both pre and post-intervention (8 weeks) GCSI scores were calculated, GES was performed to quantify the improvement in gastric emptying. Power analysis was performed using G*POWER software version 3.1.9.7 and data analysis using SPSS 23.0, variables measured in mean ± standard deviation (SD). Various statistical tests were used such as independent t-test, Chi-square test or Fisher's exact test, Wilcox Mann-Whitney test, analysis of variance (ANOVA) test, and posthoc pairwise tests. Results: The mastic gum is found effective in the improvement of 4 h gastric emptying percentage from the mean (SD) 76.60 (± 9.96) to mean (SD) 97.20 (2.17)% (P < 0.001). Mastic gum has the property of HbA1c reduction, which is more significant than that of levosulpiride (P = 0.044). Mastic gum also had significant Low density lipoprotein (LDL) (mg/dL) levels reduction, (P < 0.001), compared to levosupiride. An absolute increase was observed in haemoglobin (HB) level in mastic gum at a 2-month mean (SD) of 1.03 (0.77) (g/dL) (P-value <0.001). Conclusions: To our knowledge, this is the first study to compare the effect of levosulpiride with mastic gum concerning improvement in diabetic gastroparesis (DG) using GES. In the study, mastic gum was found to have great properties to improve DG with many important pleiotropic effects.

11.
JBRA Assist Reprod ; 28(2): 263-268, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38381778

RESUMO

OBJECTIVE: The objective of this research is to investigate the association between the concentrations of soluble human leukocyte G antigen (sHLA-G) in the follicular fluid (FF) in infertile patients with peritoneal endometriosis submitted to in vitro fertilization. METHODS: We performed a cross-sectional study, including ninety-six women undergoing in vitro fertilization (IVF) ageing ≤ 40 years. Infertile patients were classified into two groups: with endometriosis diagnosed by laparoscopy and without endometriosis due to tubal factor. ELISA measured soluble HLA-G in the FF of a pool of punctured (more than 17mm) follicles from women with endometriosis and without endometriosis who were subjected to ovulation induction for IVF. Embryos obtained after fertilization were classified according to the graduated embryo score (GES). RESULTS: Groups were comparables in terms of age, the number of follicles, AMH, FSH and all included reproductive outcomes. There was no association between sHLA-G concentrations and the average score of the generated embryos (p>0.05). Measurement of sHLA-G in the follicle fluid in women with endometriosis and without endometriosis (tubal factor) showed no significant difference (p>0.05). We also compared sHLA-G per follicle and per embryo, which were not different between both groups (p>0.05). CONCLUSIONS: Patients with peritoneal endometriosis submitted to IVF did not demonstrate an altered sHLA-G in the follicular fluid compared to the follicular fluid sHLA-G concentration in tubal factor patients. Also, this molecule was not linked to any other reproductive outcome.


Assuntos
Endometriose , Fertilização in vitro , Líquido Folicular , Antígenos HLA-G , Infertilidade Feminina , Humanos , Feminino , Endometriose/metabolismo , Líquido Folicular/metabolismo , Líquido Folicular/química , Adulto , Antígenos HLA-G/metabolismo , Antígenos HLA-G/análise , Estudos Transversais , Infertilidade Feminina/metabolismo , Gravidez
12.
Gastric Cancer ; 27(2): 324-342, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38310631

RESUMO

Helicobacter pylori (H. pylori, Hp) has been designated a class I carcinogen and is closely associated with severe gastric diseases. During colonization in the gastric mucosa, H. pylori develops immune escape by inducing host immune tolerance. The gastric epithelium acts as the first line of defense against H. pylori, with Toll-like receptors (TLRs) in gastric epithelial cells being sensitive to H. pylori components and subsequently activating the innate immune system. However, the mechanism of immune tolerance induced by H. pylori through the TLR signalling pathway has not been fully elucidated. In this research, we detected the expression of TLRs and inflammatory cytokines in GES-1 cells upon sustained exposure to H. pylori or H. pylori lysate from 1 to 30 generations and in Mongolian gerbils infected with H. pylori for 5 to 90 weeks. We found that the levels of TLR6 and inflammatory cytokines first increased and then dropped during the course of H. pylori treatment in vitro and in vivo. The restoration of TLR6 potentiated the expression of IL-1ß and IL-8 in GES-1 cells, which recruited neutrophils and reduced the colonization of H. pylori in the gastric mucosa of gerbils. Mechanistically, we found that persistent infection with H. pylori reduces the sensitivity of TLR6 to bacterial components and regulates the expression of inflammatory cytokines in GES-1 cells through TLR6/JNK signaling. The TLR6 agonist obviously alleviated inflammation in vitro and in vivo. Promising results suggest that TLR6 may be a potential candidate immunotherapy drug for H. pylori infection.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Neoplasias Gástricas , Animais , Humanos , Receptor 6 Toll-Like/metabolismo , Gerbillinae , Neoplasias Gástricas/metabolismo , Citocinas/metabolismo , Infecções por Helicobacter/complicações , Mucosa Gástrica/metabolismo
13.
Microbiol Spectr ; 12(2): e0301523, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38230931

RESUMO

Rapid and reliable detection of carbapenemase-producing Enterobacterales (CPE) is crucial for prompt treatment and infection control. Most assays target the primary four enzymes (KPC, OXA-48-like, VIM, and NDM), often missing less common variants (e.g., GES, IMI, OXA-23, and OXA-58). Therefore, assays based on the hydrolysis of carbapenems are recommended in addition to differentiation tests such as PCR or immunochromatographic assays. The aim of this study was to compare the currently Clinical and Laboratory Standards Institute (CLSI)-recommended tests mCIM (modified carbapenem inactivation method) and Carba NP with new colorimetric tests (NitroSpeed-Carba NP) and novel variations of the carbapenem inactivation method (CIM) such as simplified CIM (sCIM) or modified zinc-supplemented CIM (mzCIM). The challenge collection included 205 clinical isolates, 139 CPE vs 66 non-CPE. Among all 205 isolates, the sensitivity/specificity of mCIM was 81.3%/98.5%, Carba NP 76.3%/100%, NitroSpeed-Carba NP 86.3%/78.8%, sCIM 100%/94%, and mzCIM 97.8%/98.5%. For rare carbapenemases (n = 48), the sensitivity of mzCIM (98.3%) and sCIM (100%) was higher than that of mCIM (60.4%), Carba NP (50%), or NitroSpeed-Carba NP (70.2%). Most indeterminate results occurred for mCIM (14.4%), Carba NP (8.2%), and sCIM (6.3%). The detection of rare carbapenemases remains challenging with the currently recommended assays. The CIM-based tests demonstrated superior sensitivity, with sCIM and mzCIM outperforming the currently recommended mCIM and Carba NP, especially among isolates with weakly hydrolyzing carbapenemases (e.g., OXA-23 and OXA-58). Although colorimetric assays provide more rapid results, laboratories have to be aware of the low sensitivity for rare carbapenemases. Both sCIM and the new mzCIM performed well, are cost-effective, and can easily be implemented in any laboratory.IMPORTANCEDetection of so-called rare carbapenemases (e.g., GES, IMI, OXA-23, and OXA-58) in Enterobacterales is challenging, and data on the performance of currently available assays are scarce. This study systematically assessed the performance of currently recommended and novel hydrolysis-based assays on a set of molecularly characterized isolates. It demonstrates that the currently recommended assays mCIM and Carba NP perform well on isolates producing common carbapenemases such as KPC, VIM, NDM, and OXA-48, but have only a moderate sensitivity in the detection of rare carbapenemases. In contrast, the newer CIM-based variants, sCIM and mzCIM, are equally capable of detecting frequent and uncommon carbapenemases. These assays could potentially help to improve our knowledge on the epidemiology of these "rare" enzymes.


Assuntos
Carbapenêmicos , Gammaproteobacteria , Enterobacteriaceae , Colorimetria/métodos , Testes de Sensibilidade Microbiana , beta-Lactamases/análise , Proteínas de Bactérias/análise , Antibacterianos
14.
J Agric Food Chem ; 71(48): 18722-18734, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-37980612

RESUMO

Ethanolic gastric mucosal impairment is one of the most common disorders in the gastrointestinal system. In this study, we investigated the potential alleviating effects of sea cucumber peptides on Ges-1 impairment caused by ethanol and the associated mechanisms. The sea cucumber peptide VLLY could promote the proliferation and migration of healthy Ges-1 cells. After ethanol injury, VLLY peptide treatment could greatly promote the migration of Ges-1 cells, scavenge intracellular and mitochondrial ROS, reverse mitochondrial fission and F-actin depolymerization, and improve mitochondrial respiration. VLLY peptide restored mitochondrial dynamics by downregulating Drp1 and Fis1 and upregulating Mfn2 against excessive mitochondrial fission. In addition, the VLLY peptide maintained the mitochondrial membrane potential, ablated the leakage of cytochrome c to the cytoplasm, upregulated the expression of the antiapoptotic factor Bcl-XL, decreased the expression of the proapoptotic factors of Bax, BAD, and cleaved caspase-3, and finally blocked the mitochondria-related apoptotic pathway. These findings strongly suggested that sea cucumber peptides could promote proliferation and migration of healthy Ges-1 cells and reverse ethanol-induced excess mitochondrial fission and maintain mitochondrial homeostasis through the Fis1/Bax pathway, thereby improving ethanol-induced apoptosis. VLLY offers a new perspective for improving the ethanolic gastric mucosal epithelial cell injury.


Assuntos
Apoptose , Dinâmica Mitocondrial , Proteína X Associada a bcl-2/metabolismo , Etanol
15.
Pathogens ; 12(10)2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37887772

RESUMO

(1) Background: Pseudomonas aeruginosa is a Gram-negative bacterium with several intrinsic and acquired antimicrobial resistance mechanisms. The spread of carbapenemase-encoding genes, an acquired mechanism, enables carbapenem resistance in clinical settings. Detection of the carbapenemase-producer strains is urgent. Therefore, we aimed to characterize carbapenemase production in the clinical strains of P. aeruginosa at a tertiary-care center. (2) Methods: We included clinical strains of P. aeruginosa (from August 2011 to December 2018) with resistance towards at least one carbapenem. Strains were isolated in a tertiary-care center in Mexico City. Antimicrobial susceptibility profiles were determined by broth microdilution. Screening for carbapenemase-encoding genes was performed in all strains. Phenotypic assays (CarbaNP and mCIM) were conducted. Additional modifications to mCIM were also tested. (3) Results: One-hundred seventy-one P. aeruginosa strains out of 192 included in this study were resistant towards at least one of the carbapenems tested. Forty-seven of these strains harbored a carbapenemase-encoding gene. VIM (59.6%) and GES (23.4%) were the most frequently found carbapenemases in our study, followed by IMP (14.9%). (4) Among the most frequent carbapenemase genes identified, metallo-ß-lactamases were the most prevalent, which impair new treatment options. Searching for carbapenemase genes should be performed in resistant isolates to stop transmission and guide antimicrobial treatment.

16.
BMC Health Serv Res ; 23(1): 1129, 2023 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-37858166

RESUMO

INTRODUCTION: The public policy called Explicit health guarantees (GES) could serve as a basis for the future implementation of universal health coverage in Chile. An improvement in the quality of health of the Chilean population has been observed since the launching of the GES, which has a high adherence (84% of the beneficiary population uses this health program). This work seeks the social determinants related to a portion of the remaining 16% of people who do not use the GES. METHODS: This secondary analysis study used a sample of GES recipients (n = 164,786) from the National Socioeconomic Characterization Survey (CASEN) 2020. The GES recipients included in the study responded that they had been under medical treatment for 20 of the 85 pathologies included in the GES, and they had not had access to such policy due to "trust in physician/facility," "decided not to wait," or "lack of information." The CASEN survey chose the 20 pathologies. The Average Marginal Effects of social determinants of the non-use of the GES health plan were predicted using multivariable and panel multinomial probit regression analyses, where the outcome variable assumed three possible values (the three reasons for not accessing) while taking those variables reported in previous studies as independent variables. RESULTS: A higher probability of non-access due to distrust in the physician/facility among adults with higher economic income was found. Among those who prefer not to wait are vulnerable groups of people: women, people with a lower-middle income, those who belong to groups with longer waiting times, and ethnic groups. The people who least access the GES due to lack of information correspond to part of the migrant population and those belonging to the lowest income group. CONCLUSIONS: The GES policy must necessarily improve the timeliness and quality of the services to make them attractive to groups that currently do not have access to them, managing waiting times rather than referrals and using patient-centered evaluations, especially in those most vulnerable groups that do not access GES because they choose not to wait or lack the necessary information, thereby improving their health literacy.


Assuntos
Renda , Determinantes Sociais da Saúde , Adulto , Humanos , Feminino , Fatores Sociais , Inquéritos e Questionários , Análise de Regressão
17.
Antimicrob Agents Chemother ; 67(11): e0067523, 2023 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-37819082

RESUMO

Pseudomonas aeruginosa high-risk clones pose severe threats to public health. Here, we characterize the imipenem/relebactam (IR) resistance mechanisms in P. aeruginosa high-risk clones sequence type 235 (ST235) and ST463 in China. Minimum inhibitory concentrations (MICs) were determined, and Illumina short-read sequencing was performed for 1,168 clinical carbapenem-resistant P. aeruginosa (CRPA) isolates. The gene copy number and expression level were analyzed by Illumina sequencing depth and reverse transcription-quantitative PCR, respectively. Resistance conferred by bla GES-5 was evaluated by cloning experiments. ST463 and ST235 accounted for 9.8% (115/1,168) and 4.5% (53/1,168) of total isolates, respectively, and showed high frequencies of extensively drug-resistant and difficult-to-treat resistant phenotypes. The overall IR-resistant rate in CRPA was 21.0% (245/1,168). However, the IR resistance rate was 81.7% (94/115) in ST463-PA and 52.8% (28/53) in ST235-PA. Of the ST463 isolates, 92.2% (106/115) were Klebsiella pneumoniae carbapenemase-producing P. aeruginosa (KPC-PA), and all 94 IR-resistant ST463-PA produced KPC-2. Compared to IR-susceptible ST463 KPC-2-PA, IR-resistant ST463 KPC-2-PA exhibited significantly higher bla KPC-2 copy numbers and expression levels. In ST463 KPC-2-PA, 16 mg/L relebactam resulted in additional fourfold reductions in imipenem MIC50/90 values compared to 4 mg/L relebactam. In ST235, 1.9% (1/53) carried bla IMP carbapenemase and 54.7% (29/53) carried bla GES carbapenemase. Other than the IMP producer, all 27 IR-resistant ST235-PA produced GES-5. Cloning experiments revealed that imipenem resistance in bla GES-5-carrying PAO1 transformants was generally unaffected by relebactam. In conclusion, IR-resistant CRPA isolates in China were mainly distributed in P. aeruginosa high-risk clones ST463 and ST235. The major underlying IR resistance mechanisms were bla KPC-2 overexpression and bla GES-5 carriage.


Assuntos
Infecções por Pseudomonas , Pseudomonas aeruginosa , Humanos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , beta-Lactamases/metabolismo , Carbapenêmicos/uso terapêutico , Células Clonais/metabolismo , Imipenem/farmacologia , Imipenem/uso terapêutico , Testes de Sensibilidade Microbiana , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/metabolismo , Infecções por Pseudomonas/tratamento farmacológico
18.
Int J Mol Sci ; 24(20)2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37894827

RESUMO

Helicobacter pylori is a leading cause of chronic gastric inflammation, generally associated with gastritis and adenocarcinoma. Activation of the NF-κB pathway mainly contributes to the inflammatory phenotype observed in H. pylori infection in humans and experimental models. Since the gastric epithelium undergoes rapid turnover, inflammation and pathogenicity of H. pylori result from early phase and chronically activated pathways. In the present study we investigated the early host response to H. pylori in non-tumoral human gastric epithelial cells (GES-1). To dissect the pathogen-specific mechanisms we also examined the response to tumor necrosis factor (TNF), a prototypical cytokine. By analyzing the activation state of NF-κB signaling, cytokine expression and secretion, and the transcriptome, we found that the inflammatory response of GES-1 cells to H. pylori and TNF results from activation of multiple pathways and transcription factors, e.g., NF-κB and CCAAT/enhancer-binding proteins (CEBPs). By comparing the transcriptomic profiles, we found that H. pylori infection induces a less potent inflammatory response than TNF but affects gene transcription to a greater extent by specifically inducing transcription factors such as CEBPß and numerous zinc finger proteins. Our study provides insights on the cellular pathways modulated by H. pylori in non-tumoral human gastric cells unveiling new potential targets.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Humanos , NF-kappa B/metabolismo , Infecções por Helicobacter/complicações , Células Epiteliais/metabolismo , Inflamação/metabolismo , Mucosa Gástrica/metabolismo , Citocinas/metabolismo
19.
J Phys Condens Matter ; 35(50)2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37669661

RESUMO

van der Waals heterostructures have provided an unprecedented platform to tune many physical properties for two-dimensional materials. In this work, thermal transport properties of van der Waals heterostructures formed by vertical stacking of monolayers GeS and SnS have been investigated systematically based on machine learning interatomic potential. The effect of van der Waals interface on the lattice thermal transport of 2D SnS and GeS can be well clarified by introducing various stacking configurations. Our results indicate that the van der Waals interface can strongly suppress the thermal transport capacity for the considered heterostructures, and either the average thermal conductivity per layer or the 2D thermal sheet conductance for the considered heterostructures is lower than that of corresponding monolayers. The suppressed thermal conductivity with tunable in-plane anisotropy in SnS/GeS heterostructures can be ascribed to the enhanced interface anharmonic scattering, and thus exhibits obvious interface-dependent characteristics. Therefore, this work highlights that the van der Waals interface can be employed to effectively modulate thermal transport for the 2D puckered group-IV monochalcogenides, and the suppressed lattice thermal conductivity together with interface-dependent phonon transport properties in the SnS/GeS heterostructure imply the great potential for corresponding thermoelectrical applications.

20.
Antibiotics (Basel) ; 12(9)2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37760691

RESUMO

Carbapenem-resistant Pseudomonas aeruginosa (CRPA) are a global health concern. The antimicrobial resistance, virulence, and molecular typing of 57 CRPA isolated from 43 patients who attended a specific Tunisian hospital from September 2018 to July 2019 were analyzed. All but one were multidrug-resistant CRPA, and 77% were difficult-to-treat-resistant (DTR) isolates. The blaVIM-2 gene was detected in four strains (6.9%), and among the 36 blaGES-positive CRPA (62%), the blaGES-5 gene was the predominant variant (86%). Three strains co-harbored the blaVIM-2 and blaGES-45 genes, and seven CRPA carried the blaSHV-2a gene (14%). OprD alterations, including truncations by insertion sequences, were observed in 18 strains. Regarding the 46 class 1 integron-positive CRPA (81%), the blaGES-5 gene was located in integron In717, while the blaGES-29 and blaGES-45 genes were found in two new integrons (In2122 and In4879), and the blaVIM-2 gene was found in In1183 and the new integron In2142. Twenty-four PFGE patterns and thirteen sequence types (three new ones) were identified. The predominant serotype O:11 and exoU (81%) were mostly associated with ST235 and the new ST3385 clones. The seven blaSHV-2a-CRPA from different patients belonged to ST3385 and the same PFGE pattern. The blaGES-5- and blaVIM-2 + blaGES-45-positive CRPA recovered mostly from ICU patients belonged to the high-risk clone ST235. Our results highlight the alarming prevalence of blaGES-5- and ST235-CRPA, the co-existence of blaGES-45 and blaVIM-2, and their location within integrons favoring their dissemination.

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