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1.
Pharmacol Res ; 206: 107254, 2024 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-38862069

RESUMO

Gut damage during carbapenem-resistant and hypervirulent Klebsiella pneumoniae (CR-HvKP) infection is associated with a death risk. Understanding the mechanisms by which CR-HvKP causes intestinal damage and gut microbiota alteration, and the impact on immunity, is crucial for developing therapeutic strategies. This study investigated if gastrointestinal tract damage and disruption of gut microbiota induced by CR-HvKP infection undermined host immunity and facilitated multi-organ invasion of CR-HvKP; whether the therapeutic value of the rifampicin (RIF) and zidovudine (ZDV) combination was attributed to their ability to repair damages and restore host immunity was determined. A sepsis model was utilized to assess the intestinal pathological changes. Metagenomic analysis was performed to characterize the alteration of gut microbiota. The effects of the RIF and ZDV on suppressing inflammatory responses and improving immune functions and gut microbiota were evaluated by immunopathological and transcriptomic analyses. Rapid colonic damage occurred upon activation of the inflammation signaling pathways during lethal infections. Gut inflammation compromised host innate immunity and led to a significant decrease in probiotics abundance, including Bifidobacterium and Lactobacillus. Treatment with combination drugs significantly attenuated the inflammatory response, up-regulated immune cell differentiation signaling pathways, and promoted the abundance of Bifidobacterium (33.40 %). Consistently, supplementation of Bifidobacterium alone delayed the death in sepsis model. Gut inflammation and disrupted microbiota are key disease features of CR-HvKP infection but can be reversed by the RIF and ZDV drug combination. The finding that these drugs can restore host immunity through multiple mechanisms is novel and deserves further investigation of their clinical application potential.

2.
Andrologia ; 54(3): e14348, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34932839

RESUMO

Researches were reported that respiratory diseases can lead to male infertility; however, it is unclear whether there is a relationship between pulmonary fibrosis (PF) and male infertility. This study examined the influence of PF on sperm quality and its mechanisms. The key signalling pathway of male infertility caused by PF was predicted based on bioinformatics research. After modelling, we evaluated semen quality. Real-time quantitative polymerase chain reaction and Western blotting were used to measure the protein and mRNA expression levels of phosphatidylinositol 3-kinase (PI3K), phosphorylation-protein kinase B (p-Akt) and B-cell lymphoma 2 (Bcl2) in rat testicular cells. Compared with group A (48.77 ± 4.67; 59.77 ± 4.79), the sperm concentration and total sperm viability of group B (8.44 ± 1.71; 15.39 ± 3.48) showed a downward trend (p < 0.05). Western blotting showed that the protein expressions of PI3K, p-Akt and Bcl2 in the testes of group B (0.30 ± 0.06; 0.27 ± 0.05; 0.15 ± 0.03) was significantly lower than those of group A (0.71 ± 0.07; 0.72 ± 0.06; 0.50 ± 0.06) (p < 0.05). The hypoxic environment induced by PF can inhibit the expression of PI3K, p-Akt and Bcl2 protein and eventually cause dysfunctional spermatogenesis.


Assuntos
Proteínas Proto-Oncogênicas c-akt , Fibrose Pulmonar , Animais , Masculino , Fosfatidilinositol 3-Quinase/metabolismo , Fosfatidilinositol 3-Quinase/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fibrose Pulmonar/metabolismo , Ratos , Análise do Sêmen , Espermatozoides
3.
Pharm Biol ; 59(1): 167-174, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33569974

RESUMO

CONTEXT: The leech and centipede granules have good curative effects on many diabetic vascular diseases, including diabetes-induced erectile dysfunction (DIED). OBJECTIVE: To explore the effect of leech and centipede on erectile function in rats with diabetes-induced erectile dysfunction and its possible mechanism. MATERIALS AND METHODS: Thirty male Sprague-Dawley DIED rats were randomly divided into the model group (Group M), low-dose group (Group DD), high-dose group (Group DG) and tadalafil group (Group T) (n = 6); diabetic rats were induced by streptozotocin. Apomorphine was used to induce diabetic erectile dysfunction. The 'leech-centipede' granules (0.15 and 0.6 g/kg) were intragastrically administered in the DD and DG groups for 8 weeks. Blood glucose, serum insulin, testosterone, cGMP levels and protein expression changes were measured in each group. RESULTS: After 8 weeks, the erectile function of rats in the DG group significantly improved (1.26 ± 0.73). Penis tissue cGMP levels were higher in the DG group (1.48 ± 0.11) than in the M group (0.58 ± 0.15). Protein and mRNA expression levels of NOS were significantly higher (0.77 ± 0.05; 0.61 ± 0.02) but those of PDE5 (0.43 ± 0.05; 0.61 ± 0.03) were lower in the DG group than in the M group (0.37 ± 0.06; 0.51 ± 0.01; 0.78 ± 0.06; 0.81 ± 0.04). CONCLUSION: The leech-centipede can improve erectile dysfunction in DIED rats by regulating the expression of cGMP, NOS, and PDE5-related molecules in the PDE5 pathway. This study provides a potential mechanism for the treatment of DIED with leech-centipede.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Disfunção Erétil/tratamento farmacológico , Extratos de Tecidos/farmacologia , Animais , Glicemia/efeitos dos fármacos , GMP Cíclico/metabolismo , Nucleotídeo Cíclico Fosfodiesterase do Tipo 5/metabolismo , Diabetes Mellitus Experimental/complicações , Disfunção Erétil/etiologia , Masculino , Óxido Nítrico Sintase/metabolismo , Ereção Peniana/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Estreptozocina
4.
Pharm Biol ; 59(1): 547-556, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33962551

RESUMO

CONTEXT: Achyranthes bidentata Blume (Amaranthaceae) (ABR) and semen vaccariae (SV) are used commonly in the clinical treatment of erectile dysfunction in males with diabetes mellitus (DMED) to strengthen the kidney and promote blood circulation, and often achieve good curative effects. OBJECTIVE: Explore mechanistic details of ABR + SV treatment against DMED. MATERIALS AND METHODS: Prediction of key targets by network pharmacology. A rat model of DM was established by streptozotocin injection (55 mg/kg). Apomorphine (100 µg/kg) was injected into rats to screen the DMED model. Group C (n = 6) and group M (n = 6) were gavaged with deionized water; group T (n = 6) was given Achyranthis bidentatae radix-semen vaccariae granule suspension (2.5 g/kg). It lasted 8 weeks. Real-time reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and western blotting (WB) were used to measure the expression of tissue-related proteins and mRNA. RESULTS: The predicted key targets are albumin (ALB), caspase-3 (CASP3), vascular endothelial growth factor A (VEGFA), angiotensin-converting enzyme (ACE), and endothelial nitric oxide synthase (eNOS). Compared with the M group (0.52 ± 0.04; 0.50 ± 0.03; 0.49 ± 0.02; 0.23 ± 0.03), CASP3, VEGFA, and ACE protein expression reduced in the T group (0.39 ± 0.06; 0.34 ± 0.03; 0.39 ± 0.03), and eNOS protein expression increased (0.34 ± 0.03). CONCLUSION: ABR + SV can improve erectile function in DMED rats. This study provides a potential mechanism for the treatment of DMED with ABR + SV and can benefit from more patients.


Assuntos
Achyranthes , Diabetes Mellitus Experimental/tratamento farmacológico , Disfunção Erétil/tratamento farmacológico , Farmacologia em Rede/métodos , Extratos Vegetais/uso terapêutico , Vaccaria , Animais , Diabetes Mellitus Experimental/patologia , Modelos Animais de Doenças , Disfunção Erétil/patologia , Masculino , Extratos Vegetais/isolamento & purificação , Ratos , Ratos Sprague-Dawley , Resultado do Tratamento
5.
Zhonghua Nan Ke Xue ; 27(12): 1059-1063, 2021 Dec.
Artigo em Zh | MEDLINE | ID: mdl-37454312

RESUMO

Objective: To investigate the impact of asthma on erectile function in rats and the expressions of related proteins. METHODS: Male rats were injected intraperitoneally with ovalbumin solution to induce asthma followed by subcutaneous injection of apomorphine at 100 µg/kg into the neck, and then observed for reduced frequency or loss of penile erection. Based on the results of observation, a model of asthma-induced ED (AED) was made in 6 of the animals, and another 6 normal male rats were taken as controls. The histomorphology of the corpus cavernosum was observed by HE staining, and the mRNA and protein expressions of phosphodiesterase 5 (PDE5) and nitric oxide synthase 3 (eNOS) in the testis tissue were determined by RT-qPCR and Western blot. RESULTS: Compared with the normal controls, the rats in the AED model group showed disorderly distribution of sinusoids and decreased density of endothelial and smooth muscle cells in the corpus cavernosum. The mRNA and protein expressions of PDE5 were significantly higher (P < 0.05), while those of eNOS remarkably lower in the AED model than in the control group (P < 0.05). CONCLUSIONS: Asthma can induce ED and change the histomorphology of the corpus cavernosum in rats by affecting the expressions of PDE5 and eNOS proteins.

6.
Aging Male ; 22(4): 278-286, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30451062

RESUMO

Objective: The study was aimed to evaluate the influences of erectile dysfunction (ED) in a rat model of stroke combined with hyperlipidemia (HLP). Methods: Male Sprague-Dawley rats were divided into control and hyperlipidemia (HLP) groups. HLP model was constructed by feeding with high-fat and cholesterol diets. Serum levels of total cholesterol (TC), low density lipoprotein (LDL), high density lipoprotein (HDL), triglyceride (TG), and non-HDL were identified to check the model was success. Stroke model was established by FeCl3. ICP/MAP value was detected to evaluate the erectile function of rats. Serum level of lipoproteins and the expressions of endothelial nitric oxide synthase (eNOS), vascular endothelial growth factor (VEGF) were detected by ELISA. Hematoxylin-eosin (HE) staining of corpus cavernosum and measurement of penis length were utilized to assessment erectile function. Western blot was used. Results: TC, TG, LDL, and non-HDL-C in serum were up-regulated, while HDL level was attenuated. After treatment, the serum lipid level recovered. From the ICP/MAP values, the erectile function of both two treatment groups recovered. The expression of PDE5A was up-regulated, while the levels of eNOS and cGMP were suppressed after surgery. The length of penis was decreased, and corpus cavernosum was damaged following HLP and stroke. However, the erectile function was recovered after treatment. Conclusion: Stroke combined HLP caused ED through NO-cGMP-PDE5 pathway.


Assuntos
Disfunção Erétil , Hiperlipidemias , Acidente Vascular Cerebral , Animais , Dietoterapia/métodos , Modelos Animais de Doenças , Disfunção Erétil/sangue , Disfunção Erétil/diagnóstico , Disfunção Erétil/etiologia , Disfunção Erétil/terapia , Hiperlipidemias/sangue , Hiperlipidemias/complicações , Hiperlipidemias/fisiopatologia , Lipoproteínas/sangue , Masculino , Óxido Nítrico Sintase Tipo III/sangue , Ereção Peniana/fisiologia , Pênis/patologia , Pênis/fisiopatologia , Ratos , Ratos Sprague-Dawley , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/fisiopatologia , Fatores de Crescimento do Endotélio Vascular/sangue
7.
Cancer Cell Int ; 18: 164, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30377411

RESUMO

BACKGROUND: Primary or acquired resistance to cetuximab often occurs during targeted therapy in metastatic colorectal cancer (mCRC) patients. In many cancers, the key role of the long noncoding RNA (lncRNA) urothelial carcinoma-associated 1 (UCA1) in anticancer drug resistance has been confirmed. Emerging evidence has shown that specific exosomal lncRNAs may serve as meaningful biomarkers. In this study, we hypothesize that exosomal UCA1 might predict the response to cetuximab in CRC patients. METHODS: First, acquired cetuximab-resistant cell lines were generated, and UCA1 expressions in these cells and their exosomes were compared. We also systematically evaluate the stability of exosomal UCA1. Thereafter, the predictive value of exosomal UCA1 in CRC patients treated with cetuximab was evaluated. Finally, through cell apoptosis assays and immunofluorescence staining, we analyzed the role of UCA1-containing exosomes in conferring cetuximab resistance. RESULTS: UCA1 expression was markedly higher in cetuximab-resistant cancer cells and their exosomes. Exosomal UCA1 was shown to be detectable and stable in serum from CRC patients. In addition, circulating UCA1-containing exosomes could predict the clinical outcome of cetuximab therapy in CRC patients, and UCA1 expression was considerably higher in the progressive disease/stable disease patients than in the partial response/complete response patients. Furthermore, exosomes derived from cetuximab-resistant cells could alter UCA1 expression and transmit cetuximab resistance to sensitive cells. CONCLUSIONS: We discovered a novel role of UCA1-containing exosomes, showed their capability to transmit drug resistance and investigated their potential clinical use in predicting cetuximab resistance.

8.
Physiol Plant ; 154(1): 142-61, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25270993

RESUMO

Seed germination is a critical phase in the plant life cycle, but the specific events associated with seed germination are still not fully understood. In this study, we used two-dimensional gel electrophoresis followed by mass spectrometry to investigate the changes in the proteome during imbibition of Oryza sativa seeds at optimal temperature with or without abscisic acid (ABA) and high temperature (germination thermoinhibition) to further identify and quantify key proteins required for seed germination. A total of 121 protein spots showed a significant change in abundance (1.5-fold increase/decrease) during germination under all conditions. Among these proteins, we found seven proteins specifically associated with seed germination including glycosyl hydrolases family 38 protein, granule-bound starch synthase 1, Os03g0842900 (putative steroleosin-B), N-carbamoylputrescine amidase, spermidine synthase 1, tubulin α-1 chain and glutelin type-A; and a total of 20 imbibition response proteins involved in energy metabolism, cell growth, cell defense and storage proteins. High temperature inhibited seed germination by decreasing the abundance of proteins involved in methionine metabolism, amino acid biosynthesis, energy metabolism, reserve degradation, protein folding and stress responses. ABA treatment inhibited germination and decreased the abundance of proteins associated with methionine metabolism, energy production and cell division. Our results show that changes in many biological processes including energy metabolism, protein synthesis and cell defense and rescue occurred as a result of all treatments, while enzymes involved in methionine metabolism and weakening of cell wall specifically accumulated when the seeds germinated at the optimal temperature.


Assuntos
Ácido Abscísico/fisiologia , Germinação , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Sementes/metabolismo , Temperatura Alta , Proteoma , Plântula/crescimento & desenvolvimento
9.
Cell Physiol Biochem ; 33(5): 1527-36, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24854841

RESUMO

BACKGROUND: Photodynamic therapy (PDT) is a new treatment for esophageal cancer which has been shown to be effective in the elimination of tumor. However, PDT could induce the activation of nuclear factor-kappa B (NF-κB) in many photosensitizers based PDT, which plays a negative role in PDT. In addition, our previous results have shown that dihydroartemisinin (DHA), which was the most potent one of artemisinin derivatives, has anticancer activity in esophageal cancer cells. METHODS: Cell viability was determined by MTT analysis, and apoptosis was evaluated by flow cytometry. Nuclear extract was obtained for determining NF-κB DNA-binding activity, while total protein extract obtained for downstream gene expression by western blot. RESULTS: We demonstrated DHA enhanced PDT-induced growth inhibition and apoptosis in both human esophageal cancer cell lines Eca109 and Ec9706 in vitro. The mechanism was at least partially due to DHA deactivated PDT-induced NF-κB activation, so as to decrease tremendously the expression of its target gene Bcl-2. CONCLUSION: Our results demonstrate that DHA augments PDT-induced growth inhibition and apoptosis in esophageal cancer cells, and that inactivation of NF-κB activity is a potential mechanism by which DHA sensitizes esophageal cancer cells to PDT-induced growth inhibition and apoptosis.


Assuntos
Antineoplásicos/farmacologia , Artemisininas/farmacologia , Neoplasias Esofágicas/tratamento farmacológico , NF-kappa B/antagonistas & inibidores , Fotoquimioterapia , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Artemisininas/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patologia , Humanos , NF-kappa B/metabolismo , Relação Estrutura-Atividade
10.
Int J Antimicrob Agents ; 63(2): 107055, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38081547

RESUMO

Klebsiella pneumoniae is an important clinical bacterial pathogen that has hypervirulent and multidrug-resistant variants. Uniform Manifold Approximation and Projection (UMAP) was used to cluster genomes of 16 797 K. pneumoniae strains collected, based on core genome distance, in over 100 countries during the period 1937 to 2021. A total of 60 high-density genetic clusters of strains representing the major epidemic strains were identified among these strains. Using UMAP bedding, the relationship between genetic cluster, capsular polysaccharide (KL) types and sequence type (ST) of the strains was clearly demonstrated, with some important STs, such as ST11 and ST258, found to contain multiple clusters. Strains within the same cluster often exhibited significant diverse features, such as originating from different areas and being isolated in different years, as well as carriage of different resistance and virulence genes. These data enable the routes of evolution of the globally prevalent K. pneumoniae strains to be traced. Alarmingly, carbapenem-resistant K. pneumoniae strains accounted for 51.7% of the test strains and worldwide transmission was observed. Carbapenem-resistant and hypervirulent K. pneumoniae strains are mainly reported in China; however, these strains are increasingly reported in other parts of the world. Also identified in this study were several key genetic loci that facilitate development of a new K. pneumoniae typing method to differentiate between high- and low-risk strains. In particular, the acrR, ompK35 and hha genes were predicted to play a key role in expression of the resistance and virulence phenotypes.


Assuntos
Infecções por Klebsiella , Klebsiella pneumoniae , Humanos , Infecções por Klebsiella/epidemiologia , Infecções por Klebsiella/microbiologia , Carbapenêmicos , Virulência/genética , Genômica , Antibacterianos/farmacologia , beta-Lactamases/genética
11.
ACS Cent Sci ; 10(2): 439-446, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38435534

RESUMO

The therapeutic effects of antibodies include neutralization of pathogens, activation of the host complement system, and facilitation of phagocytosis of pathogens. However, antibody alone has never been shown to exhibit bactericidal activity. In this study, we developed a monoclonal antibody that targets the bacterial cell surface component Pseudaminic acid (Pse). This monoclonal antibody, Pse-MAB1, exhibited direct bactericidal activity on Acinetobacter baumannii strains, even in the absence of the host complements or other immune factors, and was able to confer a protective effect against A. baumannii infections in mice. This study provides new insight into the potential of developing monoclonal antibody-based antimicrobial therapy of multidrug resistant bacterial infections, especially those which occurred among immunocompromised patients.

12.
Sci Total Environ ; 926: 171924, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38522537

RESUMO

This study employs a comprehensive approach combining metagenomic analysis and bacterial isolation to elucidate the microbial composition, antibiotic resistance genes (ARGs), and virulence factors (VFGs) present in shrimps from market and supermarket. Metagenomic analysis of shrimps revealed a dominance of Proteobacteria and Bacteroidetes with Firmicutes notably enriched in some samples. On the other hand, the dominant bacteria isolated included Citrobacter portucalensis, Escherichia coli, Salmonella enterica, Vibrio species and Klebsiella pneumonaie. Metagenomic analysis unveiled a diverse spectrum of 23 main types and 380 subtypes of ARGs in shrimp samples including many clinical significant ARGs such as blaKPC, blaNDM, mcr, tet(X4) etc. Genomic analysis of isolated bacterial strains identified 14 ARG types with 109 subtype genes, which complemented the metagenomic data. Genomic analysis also allowed us to identify a rich amount of MDR plasmids, which provided further insights into the dissemination of resistance genes in different species of bacteria in the same samples. Examination of VFGs and mobile genetic elements (MGEs) in both metagenomic and bacterial genomes revealed a complex landscape of factors contributing to bacterial virulence and genetic mobility. Potential co-occurrence patterns of ARGs and VFGs within human pathogenic bacteria underlined the intricate interplay between antibiotic resistance and virulence. In conclusion, this integrated analysis for the first time provides a comprehensive view and sheds new light on the potential hazards associated with shrimp products in the markets. The findings underscore the necessity of ongoing surveillance and intervention strategies to mitigate risks posed by antibiotic-resistant bacteria in the food supply chain using the novel comprehensive approaches.


Assuntos
Decápodes , Genes Bacterianos , Animais , Humanos , Antibacterianos/farmacologia , Bactérias/genética , Plasmídeos , Resistência Microbiana a Medicamentos/genética , Crustáceos
13.
Microbiol Res ; 285: 127769, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38797112

RESUMO

Carbapenem-resistant Klebsiella pneumoniae (CRKP) has emerged as a global threat due to its high mortality in clinical patients. However, the specific mechanisms underlying this increased mortality remain unclear. The objective of this study is to investigate how the development of a resistance phenotype contributes to the significantly higher mortality associated with this pathogen. To achieve this, a collection of isogeneic strains was generated. The clinical carbapenem-susceptible K. pneumoniae (CSKP) strain HKU3 served as the control isolate, while HKU3-KPC was created through conjugation with a blaKPC-2-bearing plasmid and served as clinical CRKP strain. Using a sepsis model, it was demonstrated that both HKU3 and HKU3-KPC exhibited similar levels of virulence. Flow cytometry, RNA-seq, and ELISA analysis were employed to assess immune cell response, M1 macrophage polarization, and cytokine storm induction, revealing that both strains elicited comparable types and levels of these immune responses. Subsequently, meropenem was utilized to treat K. pneumoniae infection, and it was found that meropenem effectively reduced bacterial load, inhibited M1 macrophage polarization, and suppressed serum cytokine production during HKU3 (CSKP) infection. However, these effects were not observed in the case of HKU3-KPC (CRKP) infection. These findings provide evidence that the high mortality associated with CRKP is attributed to its enhanced survival within the host during antibiotic treatment, resulting in a cytokine storm and subsequent host death. The development of an effective therapy for CRKP infections could significantly reduce the mortality caused by this pathogen.


Assuntos
Antibacterianos , Enterobacteriáceas Resistentes a Carbapenêmicos , Carbapenêmicos , Infecções por Klebsiella , Klebsiella pneumoniae , Meropeném , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/patogenicidade , Klebsiella pneumoniae/genética , Infecções por Klebsiella/microbiologia , Infecções por Klebsiella/mortalidade , Infecções por Klebsiella/tratamento farmacológico , Virulência , Antibacterianos/farmacologia , Meropeném/farmacologia , Carbapenêmicos/farmacologia , Animais , Camundongos , Enterobacteriáceas Resistentes a Carbapenêmicos/efeitos dos fármacos , Enterobacteriáceas Resistentes a Carbapenêmicos/genética , Humanos , Macrófagos/microbiologia , Macrófagos/imunologia , beta-Lactamases/genética , beta-Lactamases/metabolismo , Sepse/microbiologia , Sepse/mortalidade , Sepse/tratamento farmacológico , Citocinas/metabolismo , Testes de Sensibilidade Microbiana , Proteínas de Bactérias/genética , Modelos Animais de Doenças , Carga Bacteriana
14.
Microbiol Res ; 282: 127672, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38447456

RESUMO

Antibiotic resistance is a global health issue, with Klebsiella pneumoniae (KP) posing a particular threat due to its ability to acquire resistance to multiple drug classes rapidly. OXA-232 is a carbapenemase that confers resistance to carbapenems, a class of antibiotics often used as a last resort for treating severe bacterial infections. The study reports the earliest known identification of six OXA-232-producing KP strains that were isolated in Zhejiang, China, in 2008 and 2009 within a hospital, two years prior to the first reported identification of OXA-232 in France. The four KP strains carry the OXA-232 gene and exhibit hypervirulent loci, suggesting a broader temporal and geographical spread and integration of this resistance and virulence than previously recognized with implications for public health. Global analysis of all OXA-232-bearing KP strains revealed that OXA-232-encoding plasmids are conservative, while the strains were very diverse suggesting the plasmid mediated transmission of this carbapenemase genes. Importantly, a large proportion of the OXA-232-bearing KP strains also carried virulence plasmids, in particular the recent emergence of ST15 type of KP that carried both OXA-232-encoding plasmids and hypervirulent (hv) plasmids in China since 2019, highlighting the importance of the emergence of this type of KP strains in clinical setting. The early detection and investigations of OXA-232 in these strains warrants the retrospective studies to uncover the true timeline of antibiotic resistance spread, which could provide valuable insights for shaping future strategies to tackle the global health crisis.


Assuntos
Proteínas de Bactérias , Klebsiella pneumoniae , Klebsiella pneumoniae/genética , Estudos Retrospectivos , Testes de Sensibilidade Microbiana , Proteínas de Bactérias/genética , Antibacterianos/farmacologia , Plasmídeos/genética , China
15.
EBioMedicine ; 101: 104998, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38340556

RESUMO

BACKGROUND: The epidemiological features of the Klebsiella pneumoniae causing bloodstream infections in Hong Kong and their potential threats to human health remained unknown. METHODS: K. pneumoniae strains collected from four hospitals in Hong Kong during the period of 2009-2018 were subjected to molecular typing, string test, antimicrobial susceptibility testing, whole genome sequencing and analysis. Clinical data of patients from whom these strains were isolated were analyzed retrospectively using univariate and multivariate logistic regression approaches. FINDINGS: The 240 Klebsiella spp. strains belonged to 123 different STs and 63 different capsule loci (KLs), with KL1 and KL2 being the major type. 86 out of 212 BSI-KP (40.6%) carried at least one of the virulence genes iuc, iro, rmpA or rmpA2. Virulence plasmid correlated well with the string test positive result, yet 8 strains without rmp genes were also hypermucoviscous, which was due to wzc mutation. The mortality rate of bloodstream infection patients was 43.0%. Univariant analysis showed that factors including renal replacement therapy (FDR adjusted p = 0.0007), mechanical ventilation (FDR adjusted p < 0.0001) and respiratory sepsis (FDR adjusted p < 0.0001) were found to pose the highest risk of death upon infection by Klebsiella spp. INTERPRETATION: This study revealed the high mortality rate and risk factors associated with bloodstream infections caused by K. pneumoniae in Hong Kong, which warrants immediate action to develop effective solution to tackle this problem. FUNDING: Theme Based Research Scheme (T11-104/22-R), Research Impact Fund (R5011-18 F) and Postdoctoral Fellowship (PDFS2223-1S09).


Assuntos
Infecções por Klebsiella , Sepse , Humanos , Hong Kong/epidemiologia , Klebsiella/genética , Epidemiologia Molecular , Estudos Retrospectivos , Infecções por Klebsiella/tratamento farmacológico , Infecções por Klebsiella/epidemiologia , Klebsiella pneumoniae/genética , Antibacterianos
16.
Microbes Infect ; : 105380, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38909679

RESUMO

Acinetobacter baumannii (AB) infections have become a global public health concern due to the continued increase in the incidence of infection and the rate of resistance to carbapenems. This study aimed to investigate the genomic features of AB strains recovered from a tertiary hospital and assess the clinical implications of the findings. A total of 217 AB strains were collected between 2016 and 2018 at a tertiary hospital in Guangzhou, with 183 (84.33%) being carbapenem-resistant AB (CRAB), with the main mechanism being the carriage of the blaOXA-23 gene. The overall mortality rate of patients caused by such strains was 15.21% (n = 33). Artificial lung ventilation and the use of meropenem were mortality risk factors in AB-infected patients, while KL2 AB infection was negatively associated. Core genome multilocus sequence typing and clustering analysis were performed on the integrated AB genome collection from the NCBI database and this study to illustrate the population structure among China. The results revealed diverse core genome profiles (n = 17) among AB strains from China, and strains from this single hospital exhibited most of the core genome profiles (n = 13), suggesting genetic variability within the hospital and transmission across the country. These findings show that the high transmission potential of the CRAB strains and meropenem usage that confers a selective advantage of CRAB clinically are two major factors that pose significant challenges to the effective clinical management of AB infections. Understanding the genetic features and transmission patterns of clinical AB strains is crucial for the effective control of infections caused by this pathogen.

17.
Int J Mol Sci ; 14(9): 18973-88, 2013 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-24065098

RESUMO

Estrogen-related genes and the fat mass and obesity-associated (FTO) gene play a critical role in estrogen metabolism, and those polymorphisms are associated with a poor prognosis in breast cancer. However, little is known about the association between these polymorphisms and the efficacy of anastrozole. The aim was to investigate the impact of the genetic polymorphisms, CYP19A1, 17-ß-HSD-1 and FTO, on the response to anastrozole in metastatic breast carcinoma (MBC) and to evaluate the impact of those polymorphisms on various clinicopathologic features. Two-hundred seventy-two women with hormone receptor-positive MBC treated with anastrozole were identified retrospectively. DNA was extracted from peripheral blood and genotyped for five variants in three candidate genes. Time to progression was improved in patients carrying the variant alleles of rs4646 when compared to patients with the wild-type allele (16.40 months versus 13.52 months; p = 0.049). The rs4646 variant alleles were significantly associated with longer overall survival (37.3 months versus 31.6 months; p = 0.007). This relationship was not observed with the rs10046, rs2830, rs9926298 and rs9939609 polymorphisms. The findings of this study indicate that rs4646 polymorphism in the CYP19A1 gene may serve as a prognostic maker of the response to anastrozole in patients with MBC who are treated with anastrozole.


Assuntos
Inibidores da Aromatase/uso terapêutico , Aromatase/genética , Neoplasias da Mama/genética , Nitrilas/uso terapêutico , Triazóis/uso terapêutico , 17-Hidroxiesteroide Desidrogenases/genética , Regiões 3' não Traduzidas , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Dioxigenase FTO Dependente de alfa-Cetoglutarato , Anastrozol , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Feminino , Frequência do Gene , Genótipo , Humanos , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Proteínas/genética , Estudos Retrospectivos , Análise de Sobrevida
18.
Microbiol Spectr ; : e0488622, 2023 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-37615439

RESUMO

In this work, we collected foodborne Salmonella strains in Shenzhen, China, during 2014-2017 and investigated the genetic profile of all cefotaxime-resistant isolates in the collection. The strains were subjected to antimicrobial susceptibility tests, whole-genome sequencing, bioinformatics analysis, and conjugation studies. A total of 79 cefotaxime-resistant Salmonella were identified and found to exhibit multidrug resistance. Resistance rate recorded during the study period increased from 1.9% to 9.1%. Salmonella Typhimurium was the predominant serovar, and CTX-M family genes were dominant among the ESBLs genes detected. Notably, CTX-M-bearing plasmids or transposons often contain other drug resistance genes. Furthermore, a combination of CTX-M-55 and CTX-M-65 genes was detected for the first time in foodborne Salmonella strains. Our findings reveal the prevalence and molecular characteristics of cefotaxime-resistant foodborne Salmonella strains in southern China. IMPORTANCE Cefotaxime-resistant Salmonella strains pose an increasing threat to human health by causing infections with limited treatment options. It is therefore necessary to undertake a surveillance on the prevalence of such strains and investigate the resistance and transmission mechanisms. In this work, various ESBL genes flanked by different IS located in different mobile genetic elements were detectable among cefotaxime-resistant Salmonella strains. These data show that the high prevalence and genotypic diversity of cefotaxime-resistant foodborne Salmonella strains in China are possibly attributed to the evolution and transmission of a wide range of multidrug resistance-encoding mobile genetic elements.

19.
Sci Total Environ ; 902: 166026, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37541513

RESUMO

Understanding tetracycline resistance in Vibrio parahaemolyticus from food products is crucial for effective control measures against this foodborne pathogen. This study aimed to investigate the prevalence, evolution routes, and mechanism of transmission of tetracycline resistance in Vibrio parahaemolyticus isolates collected from food products in Shenzhen, China. A total of 2342 non-duplicate Vibrio parahaemolyticus were isolated from 3509 food samples during the period 2013-2021. Among these 2342 Vibrio parahaemolyticus strains, 530 (21.37 %) were resistant to tetracycline. These tetracycline-resistant Vibrio parahaemolyticus strains were mainly isolated from shrimp samples, with the highest resistance rate (46.9 %) observed in 2019. Phylogenetic and genomic analyses of 387 isolates carrying the tet genes revealed that five different types of tet genes (tet(34), tet(A), tet(B), tet(M), and tet(E)) were present. The tet(A) gene was the most common (65 % of isolates), while tet(E) and tet(M) genes were only detected in specific years. Although tet(A) is the most commonly detected gene, it only encodes resistance in a low percentage of strains (47/129). On the other hand, the resistance rate is highest in isolates carrying tet(B) (41/55). Interestingly, V. parahaemolyticus carrying the tet genes were not necessarily tetracycline-resistant, and vice versa. A total of six different types of plasmids and two transposable units were found to carry the tet genes. V. parahaemolyticus strains that harbored these plasmids were often resistant to multiple antibiotics, indicating that horizontal transfer of antibiotic resistance genes is common among V. parahaemolyticus strains. Our findings suggest a high prevalence of tetracycline resistance in Vibrio parahaemolyticus strains recovered from food products in Shenzhen, China. These results provide valuable insight into the evolution and transmission of tetracycline resistance in foodborne Vibrio parahaemolyticus isolates and highlight the need for effective control measures to prevent the spread of antibiotic resistance.


Assuntos
Resistência a Tetraciclina , Vibrio parahaemolyticus , Resistência a Tetraciclina/genética , Prevalência , Filogenia , Antibacterianos/farmacologia , Tetraciclina/farmacologia , Vibrio parahaemolyticus/genética , China/epidemiologia
20.
CNS Neurosci Ther ; 29(8): 2267-2280, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36942495

RESUMO

INTRODUCTION: Neuro-navigated repetitive transcranial magnetic stimulation (rTMS) is effective in alleviating cognitive deficits in Alzheimer's disease (AD). However, the strategy for target determination and the mechanisms for cognitive improvement remain unclear. METHODS: One hundred and thirteen elderly subjects were recruited in this study, including both cross-sectional (n = 79) and longitudinal experiments (the rTMS group: n = 24; the sham group: n = 10). The cross-sectional experiment explored the precise intervention target based on the cortical-hippocampal network. The longitudinal experiment investigated the clinical efficacy of neuro-navigated rTMS treatment over a four-week period and explored its underlying neural mechanism using seed-based and network-based analysis. Finally, we applied connectome-based predictive modeling to predict the rTMS response using these functional features at baseline. RESULTS: RTMS at a targeted site of the left angular gyrus (MNI: -45, -67, 38) significantly induced cognitive improvement in memory and language function (p < 0.001). The improved cognition correlated with the default mode network (DMN) subsystems. Furthermore, the connectivity patterns of DMN subsystems (r = 0.52, p = 0.01) or large-scale networks (r = 0.85, p = 0.001) at baseline significantly predicted the Δ language cognition after the rTMS treatment. The connectivity patterns of DMN subsystems (r = 0.47, p = 0.019) or large-scale networks (r = 0.80, p = 0.001) at baseline could predict the Δ memory cognition after the rTMS treatment. CONCLUSION: These findings suggest that neuro-navigated rTMS targeting the left angular gyrus could improve cognitive function in AD patients. Importantly, dynamic regulation of the intra- and inter-DMN at baseline may represent a potential predictor for favorable rTMS treatment response in patients with cognitive impairment.


Assuntos
Doença de Alzheimer , Estimulação Magnética Transcraniana , Humanos , Idoso , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/terapia , Doença de Alzheimer/psicologia , Estudos Transversais , Lobo Parietal , Resultado do Tratamento , Imageamento por Ressonância Magnética
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