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1.
Oral Dis ; 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38623870

RESUMO

OBJECTIVES: The splicing factor transformer-2 homolog beta (Tra2ß) plays a pivotal role in various cancers. Nonetheless, its role in oral squamous cell carcinoma (OSCC) has not been comprehensively explored. This study sought to discern the influence of Tra2ß on OSCC and its underlying mechanisms. MATERIALS AND METHODS: We assessed Tra2ß expression in OSCC utilizing immunohistochemistry, qRT-PCR, and western blotting techniques. siRNA transfection was used to silence Tra2ß. Whole transcriptome RNA sequencing (RNA-seq) analysis was carried out to reveal the alternative splicing (AS) events. KEGG pathway analysis enriched the related pathways. Colony formation, transwell, wound healing, and Annexin V-FITC/PI were employed to appraise the consequences of Tra2ß silencing on OSCC. RESULTS: Tra2ß was highly expressed in both OSCC tissues and cell lines. Knockdown of Tra2ß-regulated AS events with skipped exon (SE) accounts for the highest proportion. Meanwhile, downregulation of Tra2ß reduced cell proliferation, migration, and invasion, however increasing cell apoptosis. Moreover, Wnt signaling pathway involved in the function of Tra2ß knockdown which was demonstrated directly by a discernible reduction in the expression of GSK3/ß-catenin signaling axis. CONCLUSIONS: These findings suggest that knockdown of Tra2ß may exert anti-tumor effects through the GSK3/ß-catenin signaling pathway in OSCC.

2.
Microorganisms ; 12(3)2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38543480

RESUMO

The common adverse effects and the complicated administration of tetracycline and metronidazole greatly affect the clinical application of the classical bismuth quadruple therapy (BQT) for Helicobacter pylori eradication. This pilot study aimed to evaluate the efficacy and safety of minocycline/amoxicillin-based BQT for H. pylori eradication. Firstly, consecutive H. pylori isolates collected at West China Hospital of Sichuan University between 2018 and 2021 were included for susceptibility testing of tetracycline and minocycline using E-test strips. Secondly, both treatment-naïve and experienced patients were included to receive a 14-day minocycline/amoxicillin-based BQT: esomeprazole 40 mg or vonoprazan 20 mg, bismuth colloidal pectin 300 mg, amoxicillin 1000 mg, and minocycline 100 mg, all given twice daily. Among a total of 101 H. pylori isolates, tetracycline resistance was 3.0%, whereas minocycline resistance was nil. A total of 114 patients (treatment-naïve/experienced, 72/42) received the minocycline/amoxicillin-based BQT. The overall intention-to-treat (ITT) and per protocol (PP) eradication rates were 94.7% (108/114) and 97.3% (108/111), respectively. The ITT and PP eradication rates were 91.7% (66/72) and 95.7% (66/69) among the treatment-naïve patients, and both were 100.0% among the treatment-experienced patients. No serious adverse event was recorded. This pilot study suggests that minocycline/amoxicillin-based BQT is an excellent therapy for H. pylori eradication.

3.
Curr Top Med Chem ; 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38231069

RESUMO

The Hedgehog (Hh) signaling pathway plays a crucial role in diverse biological pro-cesses such as cell differentiation, proliferation, senescence, tumorigenesis, malignant transfor-mation, and drug resistance. Aberrant Hh signaling, resulting from mutations and excessive acti-vation, can contribute to the development of various diseases during different stages of biogenesis and development. Moreover, it has been linked to unfavorable outcomes in several human can-cers, including basal cell carcinoma (BCC), multiple myeloma (MM), melanoma, and breast can-cer. Hence, the presence of mutations and excessive activation of the Hh pathway presents obsta-cles and constraints in the realm of cancer treatment. Extant research has demonstrated that small molecule inhibitors are regarded as the most effective therapeutic approaches for targeting the Hh pathway in contrast to traditional chemotherapy and radiotherapy. Consequently, this review fo-cuses on the present repertoire of small molecule inhibitors that target various components of the Hh pathway, including Hh ligands, Ptch receptors, Smo transmembrane proteins, and Gli nuclear transcription factors. This study provides a comprehensive analysis of small molecules' structural and functional aspects in the preclinical and clinical management of cancer. Additionally, it elu-cidates the obstacles encountered in targeting the Hh pathway for human cancer therapy and pro-poses potential therapeutic approaches.

4.
BMC Microbiol ; 23(1): 360, 2023 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-37993791

RESUMO

BACKGROUND: Helicobacter pylori lipopolysaccharide (LPS) structures vary among strains of different geographic origin. The aim of this study was to characterize the LPS O-antigen profiles of H. pylori strains isolated from Southwest China, and to further analyze the association of Lewis antigen expression with clinical outcomes and antibiotic resistance. RESULTS: A total of 71 H. pylori isolates from Southwest China were included for LPS profiling by silver staining and Western blotting after SDS-PAGE electrophoresis. We demonstrated that all the clinical isolates had the conserved lipid A and core-oligosaccharide, whereas the O-antigen domains varied significantly among the isolates. Compared with the common presence of the glucan/heptan moiety in LPS O-antigen structure of European strains, the clinical isolates in this study appeared to lack the glucan/heptan moiety. The expression frequency of Lex, Ley, Lea, and Leb was 66.2% (47/71), 84.5% (60/71), 56.3% (40/71), and 31.0% (22/71), respectively. In total, the expression of type II Lex and/or Ley was observed in 69 (97.2%) isolates, while type I Lea and/or Leb were expressed in 49 (69.0%) isolates. No association of Lewis antigen expression with clinical outcomes or with antibiotic resistance was observed. CONCLUSIONS: H. pylori strains from Southwest China tend to produce heptan-deficient LPS and are more likely to express type I Lewis antigens as compared with Western strains. This may suggest that H. pylori evolves to change its LPS structure for adaptation to different hosts.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Humanos , Lipopolissacarídeos/metabolismo , Antígenos O , Antígenos do Grupo Sanguíneo de Lewis/metabolismo , Glucanos
5.
Neural Netw ; 167: 668-679, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37717324

RESUMO

This article focuses on the neural adaptive output feedback control study related to nonaffine stochastic multiple-input, multiple-output nonlinear plants. First, a K-filter state observer based on a radial basis function neural network is designed to estimate the remaining unavailable states. Then, a novel adaptive command-filtered backstepping output feedback control framework is established, where an improved command filter with a fractional-order parameter is applied to conquer the calculation size problem. Specifically, the highlight of this work is that it designs a modified error compensation signal and incorporates the concept of deferred constraint to eradicate the negative effect caused by the filter errors. In addition, the network bandwidth resources, control impulse, and control accuracy are synthesized using an amended switching event-triggered mechanism. The theoretical analysis proved that the proposed control approach guarantees that the tracking error can converge to a preassigned region within a user-defined time while the violation of the deferred output constraint can be excluded. Two illustrative studies are provided to demonstrate the validity and superiority of the developed control method.


Assuntos
Algoritmos , Dinâmica não Linear , Simulação por Computador , Retroalimentação , Redes Neurais de Computação
6.
Eur J Pharmacol ; 957: 175996, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37597646

RESUMO

BACKGROUND: Frizzled 6 (Fzd6) is involved in the development of various disorders; however, its role in the etiology of depression remains unclear. We aimed to determine the potential regulatory mechanisms of Fzd6 as a Wnt receptor in depression. METHODS: Mice were divided into four groups: wild-type control (Fzd6WT-control), Fzd6 mutant control (Fzd6Q152E-control), wild-type reserpine (Fzd6WT-reserpine), and Fzd6 mutant reserpine (Fzd6Q152E-reserpine). Reserpine (0.5 mg/kg) was injected intraperitoneally for 10 days. Four behavioral experiments were performed to assess the effects of Fzd6Q152E on depression-like behaviors in the reserpine-treated mice. Blood samples were collected for an enzyme-linked immunosorbent assay (ELISA). Gene expression in the hippocampus was quantified using quantitative real-time polymerase chain reaction (qRT-PCR), and protein expression levels in the hippocampus were identified using western blotting. RESULTS: The Fzd6 mutation affected reserpine-induced depression-like behavioral changes in mice. ELISA revealed significantly reduced serum levels of 5-hydroxytryptamine (5-HT), brain-derived neurotrophic factor (BDNF), and norepinephrine in both Fzd6Q152E-reserpine and Fzd6WT-reserpine mice, with a more pronounced decrease in Fzd6Q152E-reserpine mice, especially in norepinephrine expression. The qRT-PCR results showed significantly decreased Fzd6 expression in Fzd6Q152E-reserpine mice and altered expression of Dkk2, Gsk-3ß, Lrp6, Wnt2, Wnt3, and Wnt3a in the Wnt pathway. Western blotting revealed decreased Fzd6 protein expression in Fzd6Q152E-control mice compared to Fzd6WT-control mice, whereas Fzd6 protein expression was restored in Fzd6Q152E-reserpine mice, and Gsk-3ß expression was significantly changed. CONCLUSION: Fzd6 potentially influences reserpine-induced depressive behavioral changes and serum depressive factor alterations and modulates the expression of the Wnt signaling pathway in the hippocampus of depressed mice.


Assuntos
Depressão , Via de Sinalização Wnt , Animais , Camundongos , Depressão/induzido quimicamente , Depressão/genética , Glicogênio Sintase Quinase 3 beta , Reserpina , Mutação , Norepinefrina , Serotonina
7.
Int J Mol Sci ; 24(14)2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37511140

RESUMO

Helicobacter pylori has a unique lipopolysaccharide structure that is essential in maintaining its cell envelope integrity and imbues the bacterium with natural resistance to cationic antimicrobial peptides (CAMPs). Our group has recently elucidated the complete set of LPS glycosyltransferase genes in H. pylori reference strain G27. Here, with a series of eight systematically constructed LPS glycosyltransferase gene mutants (G27ΔHP1578, G27ΔHP1283, G27ΔHP0159, G27ΔHP0479, G27ΔHP0102, G27ΔwecA, G27ΔHP1284 and G27ΔHP1191), we investigated the roles of H. pylori LPS glycosyltransferases in maintaining cell morphology, cell wall permeability, and antimicrobial susceptibilities. We demonstrated that deletion of these LPS glycosyltransferase genes did not interfere with bacterial cell wall permeability, but resulted in significant morphological changes (coccoid, coiled "c"-shape, and irregular shapes) after 48 h growth as compared to the rod-like cell shape of the wild-type strain. Moreover, as compared with the wild-type, none of the LPS mutants had altered susceptibility against clarithromycin, levofloxacin, amoxicillin, tetracycline, and metronidazole. However, the deletion of the conserved LPS glycosyltransferases, especially the O-antigen-initiating enzyme WecA, displayed a dramatic increase in susceptibility to the CAMP polymyxin B and rifampicin. Taken together, our findings suggest that the LPS glycosyltransferases play critical roles in the maintenance of the typical spiral morphology of H. pylori, as well as resistance to CAMPs and rifampicin. The LPS glycosyltransferases could be promising targets for developing novel anti-H. pylori drugs.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Humanos , Lipopolissacarídeos , Helicobacter pylori/genética , Glicosiltransferases/genética , Rifampina , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia , Metronidazol , Amoxicilina , Claritromicina , Parede Celular , Peptídeos Catiônicos Antimicrobianos , Permeabilidade , Infecções por Helicobacter/microbiologia
8.
Math Biosci Eng ; 20(5): 8561-8582, 2023 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-37161212

RESUMO

Hydraulic servo actuators (HSAs) are often used in the industry in tasks that request great power, high accuracy and dynamic motion. It is well known that an HSA is a highly complex nonlinear system, and that the system parameters cannot be accurately determined due to various uncertainties, an inability to measure some parameters and disturbances. This paper considers an event-triggered learning control problem of the HSA with unknown dynamics based on adaptive dynamic programming (ADP) via output feedback. Due to increasing practical application of the control algorithm, a linear discrete model of HSA is considered and an online learning data driven controller is used, which is based on measured input and output data instead of unmeasurable states and unknown system parameters. Hence, the ADP-based data driven controller in this paper requires neither the knowledge of the HSA dynamics nor exosystem dynamics. Then, an event-based feedback strategy is introduced to the closed-loop system to save the communication resources and reduce the number of control updates. The convergence of the ADP-based control algorithm is also theoretically shown. Simulation results verify the feasibility and effectiveness of the proposed approach in solving the optimal control problem of HSAs.

9.
J Infect Dis ; 226(Suppl 5): S503-S509, 2022 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-36478246

RESUMO

BACKGROUND: Helicobacter pylori eradication regimens should be guided by antimicrobial susceptibility testing. The objective of this study was to evaluate the molecular-based Mosprie assay for detecting H. pylori resistance to clarithromycin and levofloxacin using gastric biopsies. METHODS: A total of 185 culture-positive frozen gastric biopsies were included for Mosprie assay and also for 23S rRNA and gyrA gene sequencing. The susceptibility results by the Mosprie assay were compared with the E-test results retrospectively retrieved. The discordant results were analyzed by sequencing of the 23S rRNA and gyrA genes. RESULTS: Susceptibility concordance between the Mosprie assay and E-test for clarithromycin and levofloxacin was 97.30% (180/185) and 88.11% (163/185), respectively. The full agreement between clarithromycin genotypes by Mosprie assay and the 23S rRNA sequencing results was observed in the 5 samples with discordant Mosprie assay and E-test results. However, for levofloxacin, of the 16 discordant samples with resistant phenotype but a susceptible genotype by Mosprie assay, 6 were found to have levofloxacin resistance-related gyrA gene mutations. CONCLUSIONS: The rapid and reliable Mosprie assay can be recommended for H. pylori susceptibility testing of clarithromycin and levofloxacin on gastric biopsies. Future technical improvements are needed in detecting levofloxacin resistance-associated gene mutations.


Assuntos
Claritromicina , Helicobacter pylori , Claritromicina/farmacologia , Levofloxacino/farmacologia , Helicobacter pylori/genética , Estudos Retrospectivos
10.
J Infect Dis ; 226(Suppl 5): S479-S485, 2022 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-36478247

RESUMO

BACKGROUND: The aim of this study was to evaluate the rifamycin cross-resistance in Helicobacter pylori, and whether the use of rifampicin E-test strips to screen H. pylori rifabutin resistance is appropriate. METHODS: A total of 89 H. pylori isolates were included. Rifampicin minimum inhibitory concentrations (MICs) were obtained by E-test, while the MICs for rifapentine, rifaximin, and rifabutin were determined by agar dilution method. The rifamycin resistance rates based on different breakpoints were compared. Isolates with high-level rifampicin resistance were subjected to whole-genome sequencing. RESULTS: A wide distribution of MICs (mostly in the range 0.125-8 mg/L) was observed for rifampicin, rifapentine, and rifaximin. Using MIC >1, ≥ 4, and > 4 mg/L as the breakpoints, resistance rates to rifampicin/rifapentine/rifaximin were 60.4%/48.3%/38.2%, 28.1%/25.8%/23.6%, and 15.7%/16.9%/7.9%, respectively. However, the rifabutin MICs of all the tested H. pylori isolates were extremely low (≤0.016 mg/L). Applying MIC ≥ 0.125 mg/L as the breakpoint, rifabutin resistance was nil. No mutation was found in the rpoB gene sequences of the 2 isolates with high-level rifampicin resistance. CONCLUSIONS: There is a lack of cross-resistance between rifabutin and other rifamycins in H. pylori. The use of rifampicin E-test to predict H. pylori rifabutin resistance is inappropriate.


Assuntos
Helicobacter pylori , Rifabutina , Rifabutina/farmacologia , Helicobacter pylori/genética
11.
J Infect Dis ; 226(Suppl 5): S486-S492, 2022 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-36478248

RESUMO

BACKGROUND: Helicobacter pylori infection is an infectious disease and thus the eradication treatment should be guided by susceptibility testing. This study aimed to assess the applicability of broth microdilution as a routine susceptibility testing method for H. pylori. METHODS: Susceptibility profiles of clarithromycin (CLR) and levofloxacin (LEV) resistance in 76 clinical H. pylori isolates were simultaneously assessed using agar dilution and broth microdilution methods. The correlation between the minimum inhibitory concentrations (MICs) obtained by the 2 methods was assessed by means of linear regression analysis. RESULTS: The correlation between the MICs determined by broth microdilution method and agar dilution method was good for both CLR (r = 0.966) and LEV (r = 0.959). The susceptibility agreement between the 2 methods was 100% for CLR and 96.1% for LEV. Using the broth microdilution method, the false resistance was found in 3.9% (3 of 76) strains for LEV susceptibility testing. No false susceptibility was found for either CLR or LEV, and no false resistance was found for susceptibility testing of CLR. CONCLUSIONS: The broth microdilution method is suitable for routine susceptibility testing of clinical H. pylori isolates.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Humanos
12.
Int J Mol Sci ; 23(18)2022 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-36142176

RESUMO

The pathogenesis of type 2 diabetes (T2D) is highly related to the abnormal self-assembly of the human islet amyloid polypeptide (hIAPP) into amyloid aggregates. To inhibit hIAPP aggregation is considered a promising therapeutic strategy for T2D treatment. Melatonin (Mel) was reported to effectively impede the accumulation of hIAPP aggregates and dissolve preformed fibrils. However, the underlying mechanism at the atomic level remains elusive. Here, we performed replica-exchange molecular dynamics (REMD) simulations to investigate the inhibitory effect of Mel on hIAPP oligomerization by using hIAPP20-29 octamer as templates. The conformational ensemble shows that Mel molecules can significantly prevent the ß-sheet and backbone hydrogen bond formation of hIAPP20-29 octamer and remodel hIAPP oligomers and transform them into less compact conformations with more disordered contents. The interaction analysis shows that the binding behavior of Mel is dominated by hydrogen bonding with a peptide backbone and strengthened by aromatic stacking and CH-π interactions with peptide sidechains. The strong hIAPP-Mel interaction disrupts the hIAPP20-29 association, which is supposed to inhibit amyloid aggregation and cytotoxicity. We also performed conventional MD simulations to investigate the influence and binding affinity of Mel on the preformed hIAPP1-37 fibrillar octamer. Mel was found to preferentially bind to the amyloidogenic region hIAPP20-29, whereas it has a slight influence on the structural stability of the preformed fibrils. Our findings illustrate a possible pathway by which Mel alleviates diabetes symptoms from the perspective of Mel inhibiting amyloid deposits. This work reveals the inhibitory mechanism of Mel against hIAPP20-29 oligomerization, which provides useful clues for the development of efficient anti-amyloid agents.


Assuntos
Diabetes Mellitus Tipo 2 , Melatonina , Amiloide/metabolismo , Proteínas Amiloidogênicas , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Humanos , Ligação de Hidrogênio , Polipeptídeo Amiloide das Ilhotas Pancreáticas/química , Melatonina/farmacologia , Simulação de Dinâmica Molecular , Conformação Proteica em Folha beta
13.
ISA Trans ; 130: 692-701, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36055825

RESUMO

The finite-time synchronization issue of reaction-diffusion memristive neural networks (RDMNNs) is studied in this paper. To better synchronize the parameter-varying drive and response systems, an innovative gain-scheduled integral sliding mode control scheme is proposed, where the 2n controller gains can be scheduled and an integral switching surface function that contains a discontinuous term is involved. Moreover, by constructing a novel Lyapunov-Krasovskii functional and combining reciprocally convex combination (RCC) method, a less conservative finite-time synchronization criterion for RDMNNs is derived in the form of linear matrix inequalities (LMIs). Finally, three numerical simulations are exploited to illustrate the effectiveness, superiority and practicability of this paper.


Assuntos
Redes Neurais de Computação , Difusão , Fatores de Tempo
14.
BMC Microbiol ; 22(1): 196, 2022 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-35964011

RESUMO

BACKGROUND: The prevalence of Helicobacter pylori antibiotic susceptibility in the Tibet Autonomous Region, China is not determined. This study aimed to evaluate the antibiotic resistance patterns of H. pylori isolates there. RESULTS: A total of 153 (38.5%) H. pylori strains were successfully isolated from 397 patients in People's Hospital of Tibet Autonomous Region, China. The overall resistance rates were as follows: clarithromycin (27.4%), levofloxacin (31.3%), metronidazole (86.2%), amoxicillin (15.6%), tetracycline (0%), furazolidone (0.6%), and rifampicin (73.2%). Only 2.0% of H. pylori isolates were susceptible to all tested antimicrobials, with mono resistance, dual resistance, triple resistance, quadruple resistance, and quintuple resistance being 18.3%, 44.4%, 18.3%, 12.4%, and 4.6%, respectively. The resistance rates to levofloxacin (40.5%) and amoxicillin (21.5%) in strains isolated from female patients were significantly higher than those from male patients (21.6% and 9.5%, respectively). CONCLUSIONS: This study demonstrates high H. pylori resistance rates to clarithromycin, levofloxacin, metronidazole, and rifampicin, whereas moderate resistance to amoxicillin, and negligible resistant to tetracycline, and furazolidone in Tibet Autonomous Region, China. The high resistance to rifampicin warns further investigation of its derivative, rifabutin.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Amoxicilina , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , China/epidemiologia , Claritromicina , Farmacorresistência Bacteriana , Feminino , Furazolidona , Infecções por Helicobacter/tratamento farmacológico , Infecções por Helicobacter/epidemiologia , Humanos , Levofloxacino , Masculino , Metronidazol , Testes de Sensibilidade Microbiana , Rifampina , Tetraciclina/farmacologia , Tibet/epidemiologia
15.
Spectrochim Acta A Mol Biomol Spectrosc ; 276: 121195, 2022 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-35366509

RESUMO

Herein, a novel type of red-emitting carbon dots called TN-CDs was created via a one-step hydrothermal approach using neutral red and tartaric acid as raw materials. The fluorescence of TN-CDs was gradually quenched as the amount of water increased, and the color of the solution changed from yellow to pink mauve (or purple to pink). The reaction could be completed within only 5 s in various organic solvents such as N,N-Dimethylformamide (DMF), methanol (MeOH), acetonitrile (ACN), and ethanol (EtOH) with linear detection ranges of 1.2%-35.0%, 0.5%-20.0%, 0.25%-5.0% and 0%-16.0%, respectively. In addition, we prepared a reusable test strip and then combined it with TN-CDs to detect water content in DMF, as well as integrated it with smartphone software, a UV lamp, and a dark chamber for real-time, on-site, visual quantitative detection of the water content.


Assuntos
Carbono , Água , Corantes Fluorescentes , Smartphone , Solventes
16.
Helicobacter ; 27(2): e12873, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35151236

RESUMO

BACKGROUND AND AIMS: As with other infectious diseases, Helicobacter pylori eradication regimens should be guided by susceptibility testing to achieve excellent success rate, especially in the era of high antibiotic resistance. However, susceptibility testing for H. pylori is rarely performed, which can be partly ascribed to the current lack of standardization of testing methods and the lack of unified consensus on the antibiotic resistance breakpoints. The aim of this review was to call for an international consensus on standardization and harmonization of H. pylori susceptibility testing. METHODS: We summarize and compare the advantages and disadvantages of four different phenotypic antimicrobial susceptibility testing (AST) methods (agar dilution, E-test, disk diffusion, and broth microdilution) and the molecular susceptibility testing method for H. pylori. RESULTS: The standard phenotypic testing methods and the molecular testing methods have their own advantages and disadvantages. Compared to the standard phenotypic methods, the molecular testing method does not require successful H. pylori culture, and therefore, is much more rapid and convenient for clinical use. However, the currently available molecular testing method is only suitable for detecting clarithromycin and quinolone susceptibility profiles in H. pylori. Although the standard AST is time-consuming, it is currently the only way to test the susceptibility of H. pylori to all the commonly used antibiotics. CONCLUSION: To make H. pylori susceptibility testing become a clinical routine, an international consensus on standardization and harmonization of H. pylori AST is needed. Future efforts are needed for optimizing broth culture of H. pylori, and developing commercial AST plates for achieving high throughput and automated susceptibility testing for H. pylori.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Claritromicina , Farmacorresistência Bacteriana , Infecções por Helicobacter/diagnóstico , Infecções por Helicobacter/tratamento farmacológico , Humanos , Testes de Sensibilidade Microbiana , Padrões de Referência
17.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 38(6): 644-649, 2022 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-37308410

RESUMO

Objective: To study the protective effects of resveratrol (RSV) on cardiac function in rats with high altitude hypobaric hypoxia and its mechanisms. Methods: Thirty-six rats were randomly divided into control group, hypobaric hypoxia group (HH) and hypobaric hypoxia + RSV group (HH+RSV) according to the random number, 12 rats in each group. Rats in the HH and HH+RSV groups were subjected to chronic long-term high altitude hypobaric hypoxia intervention for 8 weeks in a hypobaric chamber at a simulated altitude of 6 000 m for 20 h / d. The rats of HH + RSV were fed with RSV at a dose of 400 mg/(kg·d). The rats were tested once a week for body weight and twice a week for food intake. Before execution, the rats were tested by blood cell analyzer for routine blood parameters and echocardiogram for cardiac function parameters in each group. The routine blood indexes of each group were measured by blood cell analyzer, the cardiac function indexes of each group were measured by echocardiography, myocardial hypertrophy was evaluated by HE staining, myocardial tissue reactive oxygen levels were evaluated by dihydroethidium (DHE) staining. Oxidative stress was evaluated by serum and myocardial tissue total antioxidant capacity (T-AOC), superoxide dismutase activity (SOD) and malondialdehyde (MDA) content. Results: Compared with the C group, the body mass and food intake of rats were decreased significantly (P<0.05) in HH group, while compared with the C group, RSV had no significant effects on the body mass and food intake of rats in the HH+RSV group (P>0.05). Compared with the C group, the levels of erythrocytes and hemoglobin of rats in the HH group were increased significantly (P<0.05), while the platelet concentration was decreased significantly(P<0.05); compared with the HH group, the erythrocyte and hemoglobin levels were decreased significantly (P<0.05) and platelet concentration was increased significantly(P<0.05) in rats of the HH+RSV group. Compared with the C group, the cardiac coefficient, myocardial fiber diameter and thickness were significantly increased in the HH group (P<0.05); compared with the HH group, the cardiac coefficient and myocardial fiber thickness were significantly decreased in the HH+RSV group (P<0.05). Echocardiographic analysis showed a significant increase in ventricular wall thickness (P<0.05) and a significant decrease in ejection fraction and cardiac output (P<0.05) in the HH group compared with the C group, and a significant decrease in ventricular wall thickness and a significant improvement in cardiac function (P<0.05) in the HH+RSV group compared with the HH group. The results of DHE staining showed that myocardial tissue reactive oxygen levels were increased significantly in the HH group compared with the C group (P<0.05); myocardial tissue reactive oxygen levels were significantly restored in the HH+RSV group compared with the HH group (P<0.05). The oxidative/antioxidant results showed that the serum and myocardial T-AOC and SOD activities were decreased significantly (P<0.05) and the MDA level was increased significantly (P<0.05) in the HH group compared with the C group; the serum and myocardial T-AOC and SOD activities were increased significantly (P<0.05) and the MDA level was decreased significantly(P<0.05) in the HH+RSV group compared with the HH group. Conclusion: Long-term plateau hypobaric hypoxia exposure leads to myocardial hypertrophy and reduced cardiac function in rats. Resveratrol intervention significantly improves myocardial hypertrophy and cardiac function in rats caused by altitude hypobaric hypoxia exposure, which is closely related to reducing of reactive oxygen species and improving myocardial oxidative stress levels.


Assuntos
Doença da Altitude , Antioxidantes , Animais , Ratos , Resveratrol , Hipóxia , Oxigênio , Hipertrofia , Superóxido Dismutase
18.
IEEE Trans Cybern ; 52(1): 178-191, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32142465

RESUMO

This article investigates a spatial- L∞ -norm-based reliable bounded control problem for a class of nonlinear partial differential equation systems in a finite-time interval. The main novelties are reflected in the following aspects: 1) inspired by the sector-nonlinearity approach, the considered nonlinear system is reconstructed by a Takagi-Sugeno fuzzy model, which provides an effective method for control design. Besides, several actuator failures, such as stuck faulty, outage faulty, and bias faulty, are taken into account and modeled by a novel Markov process; 2) partial areas' states are sampled and transmitted based on a new distributed event-triggered communication strategy, which reduces the cost of the system design and saves the limited network resources to some extent; and 3) on the basis of the first two works, a new piecewise fuzzy controller, which requires fewer actuators compared with the distributed control method, is constructed. Then, some sufficient conditions to guarantee the finite-time boundedness (in the sense of spatial L∞ norm) and mixed L2-L∞/H∞ disturbance attenuation performance are established, and a new linear matrix inequality relax technique is introduced to deal with the strict constraint that is caused by the asynchronous phenomenon between plant and controller. Finally, two simulation studies are given to illustrate the effectiveness and advantages of the developed controller.

19.
IEEE Trans Neural Netw Learn Syst ; 33(9): 5045-5056, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-33819162

RESUMO

For the considered reaction-diffusion inertial memristive neural networks (IMNNs), this article proposes a novel gain-scheduled generalized pinning control scheme, where three pinning control strategies are involved and 2n controller gains can be scheduled for different system parameters. Moreover, a time delay is considered in the controller to make it has a memory function. With the designed controller, drive-and-response systems can be synchronized within a finite-time interval. Note that the final finite-time synchronization criterion is obtained in the forms of linear matrix inequalities (LMIs) by introducing a memristor-dependent sign function into the controller and constructing a new Lyapunov-Krasovskii functional (LKF). Furthermore, by utilizing some improved integral inequality methods, the conservatism of the main results can be greatly reduced. Finally, three numerical examples are provided to illustrate the feasibility, superiority, and practicability of this article.


Assuntos
Redes Neurais de Computação , Difusão , Fatores de Tempo
20.
IEEE Trans Neural Netw Learn Syst ; 33(10): 5416-5428, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33852399

RESUMO

This article considers neural network (NN)-based adaptive finite-time resilient control problem for a class of nonlinear time-delay systems with unknown fault data injection attacks and actuator faults. In the procedure of recursive design, a coordinate transformation and a modified fractional-order command-filtered (FOCF) backstepping technique are incorporated to handle the unknown false data injection attacks and overcome the issue of "explosion of complexity" caused by repeatedly taking derivatives for virtual control laws. The theoretical analysis proves that the developed resilient controller can guarantee the finite-time stability of the closed-loop system (CLS) and the stabilization errors converge to an adjustable neighborhood of zero. The foremost contributions of this work include: 1) by means of a modified FOCF technique, the adaptive resilient control problem of more general nonlinear time-delay systems with unknown cyberattacks and actuator faults is first considered; 2) different from most of the existing results, the commonly used assumptions on the sign of attack weight and prior knowledge of actuator faults are fully removed in this article. Finally, two simulation examples are given to demonstrate the effectiveness of the developed control scheme.

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