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1.
Mol Biol Rep ; 51(1): 978, 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39269555

RESUMEN

BACKGROUND: Tumour necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) is an apoptosis inducer that exhibits an ideal therapeutic safety profile with less adverse effects than conventional chemotherapy. However, the occurrence of TRAIL resistance has been reported in various cancers including colorectal cancer (CRC). Substantial efforts have been channelled towards managing TRAIL resistance including identifying molecular targets. Interleukins (ILs) have been recently shown to play critical roles in modulating TRAIL sensitivity in cancer cells. METHODS AND RESULTS: This study investigated the roles of two ILs, IL-8 and IL⍺, in TRAIL resistance in CRC. TRAIL-resistant HT-29 and TRAIL-sensitive HCT 116 cells, were treated with human recombinant IL-8 and IL-1⍺. The results indicated that treatment with IL-8 (2.5 ng/mL) significantly protected TRAIL-sensitive HCT 116 cells from TRAIL-induced cell death (p < 0.05). However, IL-1⍺ did not play a role in modulating CRC cells' responses to TRAIL. Data from RT-qPCR and Western blotting revealed the molecular regulations of IL-8 on TRAIL decoy receptor genes (OPG) and autophagy-related genes (BECN1 and LC3B) expression. The activation of the phosphoinositide 3-kinase (PI3K) pathway was shown to counteract TRAIL-induced cell death. By inhibiting its activation with wortmannin, the protective role of IL-8 against TRAIL treatment was reversed, suggesting the involvement of the PI3K pathway. CONCLUSION: Collectively, findings from this study identified the role of IL-8 and PI3K in modulating CRC cells' sensitivity to TRAIL. Further validation of these two potential molecular targets is warranted to overcome TRAIL resistance in CRC.


Asunto(s)
Apoptosis , Neoplasias Colorrectales , Interleucina-8 , Fosfatidilinositol 3-Quinasas , Transducción de Señal , Ligando Inductor de Apoptosis Relacionado con TNF , Humanos , Ligando Inductor de Apoptosis Relacionado con TNF/farmacología , Ligando Inductor de Apoptosis Relacionado con TNF/metabolismo , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/patología , Interleucina-8/metabolismo , Interleucina-8/genética , Células HCT116 , Fosfatidilinositol 3-Quinasas/metabolismo , Transducción de Señal/efectos de los fármacos , Células HT29 , Apoptosis/efectos de los fármacos , Resistencia a Antineoplásicos/efectos de los fármacos , Resistencia a Antineoplásicos/genética , Línea Celular Tumoral , Muerte Celular/efectos de los fármacos
2.
Bioprocess Biosyst Eng ; 47(8): 1163-1182, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38491194

RESUMEN

Alternanthera sessilis (AS) leaf extract was used to synthesize zinc oxide nanoparticles (ZnO NPs). Bioanalytical characterization techniques such as X-ray diffraction (XRD) and field emission scanning electron microscope (FESEM) confirmed the formation of crystalline ZnO NPs with average sizes of 40 nm. The AS-ZnO NPs antimicrobial activity was analyzed under dark (D) and white light (WL) conditions. The improved antimicrobial activity was observed against Escherichia coli, Staphylococcus aureus and Bacillus subtilis at the minimal inhibitory concentration (MIC) of 125 and 62.5 µg/mL under WL than the D at 125 and 250 µg/mL for E. coli, B. subtilis, and Pseudomonas aeruginosa, respectively. In contrast, the growth of P. aeruginosa and S. aureus was not completely inhibited until 1 mg/mL AS-ZnO NPs under WL and D. Similarly, AS-ZnO NPs displayed a weaker inhibitory effect against carbapenem-sensitive P. aeruginosa (CSPA) and carbapenem-resistant P. aeruginosa (CRPA) strains of PAC023, PAC041 and PAC032, PAC045 under D. Interestingly, the distinct inhibitory effect was recorded against CSPA PAC041 and CRPA PAC032 in which the bacteria growth was inhibited 99.9% at 250, 500 µg/mL under WL. The cytotoxicity results suggested AS-ZnO NPs demonstrated higher toxicity to MCF-7 breast cancer cells than the RAW264.7 macrophage cells. Further, AS-ZnO NPs exhibited higher catalytic potential against tetracycline hydrochloride (TC-H) degradation at 65.6% and 60.8% under WL than the dark at 59.35% and 48.6% within 120 min. Therefore, AS-ZnO NPs can be used to design a photo-improved antimicrobial formulation and environmental catalyst for removing TC-H from wastewater.


Asunto(s)
Antineoplásicos , Pseudomonas aeruginosa , Tetraciclina , Óxido de Zinc , Óxido de Zinc/química , Óxido de Zinc/farmacología , Pseudomonas aeruginosa/efectos de los fármacos , Pseudomonas aeruginosa/crecimiento & desarrollo , Tetraciclina/farmacología , Tetraciclina/química , Ratones , Antineoplásicos/farmacología , Antineoplásicos/química , Nanopartículas del Metal/química , Animales , Antibacterianos/farmacología , Antibacterianos/química , Pruebas de Sensibilidad Microbiana , Humanos , Extractos Vegetales/química , Extractos Vegetales/farmacología , Farmacorresistencia Bacteriana , Células RAW 264.7 , Nanopartículas/química
3.
Toxicol Appl Pharmacol ; 481: 116767, 2023 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-38007073

RESUMEN

Current treatments for stomach cancer are often effective in curing cancer. However, these treatments can also have significant side effects, and they may not be effective in all cases. Hence synthetic compounds exhibit promise as potential agents for cancer treatment. In a previous study, we identified (E)-N'- (2,3,4-trihydroxybenzylidene) isonicotinohydrazide (ITHB4) as a novel antimycobacterial derivative of isoniazid with cytotoxic effects on the MCF-7 breast cancer cell line. This led us to investigate the potential anti-cancer properties of ITHB4 against adenocarcinoma gastric (AGS) cell line. The cytotoxic effect of ITHB4 has been determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay and further confirmed for anticancer properties by means of apoptosis, reactive oxygen species (ROS), nuclear fragmentation, lactate dehydrogenase (LDH), caspases, cytokines and morphological including phenotypic changes of cells assay. The ITHB4 demonstrated a lower IC50 in inhibiting growth of AGS cells at 24 h compared to 48 and 72 h. ITHB4 has also shown no toxicity human immune cells. Treatment of ITHB4 against AGS for 24 h eventually lead to formation of early apoptotic AGS cells, reduced mitochondrial membrane potential, nuclear condensation, and nuclear fragmentation lastly increased in ROS levels together with the release of LDH, and secretion of caspases. The altered cytokine profile in ITHB4 treated AGS hints at the possibility that ITHB4 may possess anti-tumor and anti-inflammatory properties. Our results in this study demonstrate that ITHB4 has almost similar chemotherapeutic properties against gastric adenocarcinoma cells compared to breast cancer cell. This is suggesting that the anticancer capabilities of this compound should be in vivo and clinically assessed.


Asunto(s)
Adenocarcinoma , Antineoplásicos , Neoplasias de la Mama , Neoplasias Gástricas , Humanos , Femenino , Neoplasias Gástricas/metabolismo , Isoniazida/farmacología , Especies Reactivas de Oxígeno/metabolismo , Línea Celular Tumoral , Apoptosis , Caspasas , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Adenocarcinoma/metabolismo , Neoplasias de la Mama/tratamiento farmacológico , Proliferación Celular
4.
Microb Pathog ; 161(Pt A): 105231, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34619310

RESUMEN

The interplay of immune mediators is paramount to optimal host anti-viral immune responses, especially against chronic hepatitis B virus (HBV) infection. Here, we investigated the dynamic changes in host immune responses in chronic HBV-infected individuals with and without liver cirrhosis by examining the signatures of apoptosis and plasma levels of pro-inflammatory cytokines, chemokines, and cytotoxic proteins. A total of 40 chronic HBV patients with and without liver cirrhosis were studied for plasma levels of immune mediators, and signatures of apoptosis in peripheral blood mononuclear cells (PBMCs). The intracellular concentrations of reactive oxygen species (ROS) in patients with chronic HBV with liver cirrhosis was relatively higher as compared to chronic HBV patients. The onset of apoptosis was sustained due to ongoing liver inflammation in concert with plasma TNF-α and IL-6 levels. Plasma VEGF was upregulated among chronic HBV patients with liver cirrhosis, whereas CCL2, CCL5 and granzyme B levels were down-regulated. High levels of ROS, IL-6 and TNF-α correlated with ongoing inflammation among chronic HBV patients with liver cirrhosis, which likely attributed to the expression of biosignatures of apoptosis and activation in immune cells.


Asunto(s)
Hepatitis B Crónica , Citocinas , Virus de la Hepatitis B , Hepatitis B Crónica/complicaciones , Humanos , Leucocitos Mononucleares , Cirrosis Hepática
5.
Genomics ; 112(1): 501-512, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-30980902

RESUMEN

Differences in expression of potential virulence and survival genes were associated with B. pseudomallei colony morphology variants. Microarray was used to investigate B. pseudomallei transcriptome alterations among the wild type and small colony variant (SCV) pre- and post-exposed to A549 cells. SCV pre- and post-exposed have lower metabolic requirements and consume lesser energy than the wild type pre- and post-exposed to A549. However, both the wild type and SCV limit their metabolic activities post- infection of A549 cells and this is indicated by the down-regulation of genes implicated in the metabolism of amino acids, carbohydrate, lipid, and other amino acids. Many well-known virulence and survival factors, including T3SS, fimbriae, capsular polysaccharides and stress response were up-regulated in both the wild type and SCV pre- and post-exposed to A549 cells. Microarray analysis demonstrated essential differences in bacterial response associated with virulence and survival pre- and post-exposed to A549 cells.


Asunto(s)
Burkholderia pseudomallei/genética , Burkholderia pseudomallei/patogenicidad , Células A549 , Apoptosis , Burkholderia pseudomallei/efectos de los fármacos , Burkholderia pseudomallei/metabolismo , Farmacorresistencia Bacteriana/genética , Perfilación de la Expresión Génica , Humanos , Viabilidad Microbiana , ARN Bacteriano/aislamiento & purificación , Estrés Fisiológico/genética , Virulencia , Factores de Virulencia/genética
6.
BMC Infect Dis ; 18(1): 455, 2018 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-30185168

RESUMEN

BACKGROUND: Burkholderia pseudomallei is the causative agent of melioidosis, which is a potentially life threatening disease endemic in Southeast Asian countries. In Malaysia, cystic fibrosis (CF) is an uncommon condition. The association between CF and B.pseudomallei infections has been reported previously. However, this is the first case report of a pediatric melioidosis relapse and co-infection with other Gram-negative bacteria in Malaysia. CASE PRESENTATION: A 14-year-old Chinese Malaysian boy presented with a history of recurrent pneumonia, poor growth and steatorrhoea since childhood, and was diagnosed with CF. B. pseudomallei was cultured from his sputum during three different admissions between 2013 and 2016. However, the patient succumbed to end stage of respiratory failure in 2017 despite antibiotics treatment against B.pseudomallei. The isolates were compared using multilocus-sequence typing and repetitive-element polymerase chain reaction (PCR), and confirmed that two of the isolates were of same sequence type, which may indicate relapse. CONCLUSIONS: CF patients should be aware of melioidosis in endemic regions, as it is an emerging infectious disease, especially when persistent or recurrent respiratory symptoms and signs of infection occur. The high prevalence rates of melioidosis in Malaysia warrants better management options to improve quality of life, and life expectancy in patients with CF. Travel activities to endemic regions should also be given more consideration, as this would be crucial to identify and initiate appropriate empiric treatment.


Asunto(s)
Fibrosis Quística/diagnóstico , Melioidosis/diagnóstico , Adolescente , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Burkholderia pseudomallei/efectos de los fármacos , Burkholderia pseudomallei/genética , Burkholderia pseudomallei/aislamiento & purificación , Enfermedad Crónica , Fibrosis Quística/complicaciones , ADN Bacteriano/aislamiento & purificación , ADN Bacteriano/metabolismo , Humanos , Malasia , Masculino , Melioidosis/complicaciones , Melioidosis/tratamiento farmacológico , Tipificación de Secuencias Multilocus , Neumonía/complicaciones , Neumonía/diagnóstico , Recurrencia , Esputo/microbiología , Tomografía Computarizada por Rayos X
7.
J Infect Dis ; 211(5): 827-34, 2015 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-25165162

RESUMEN

OBJECTIVES: The bsa locus of Burkholderia pseudomallei encodes several proteins that are components of the type III secretion system (TTSS). BipC was postulated as one of the TTSS-3 effector proteins, but its role in the pathogenesis of B. pseudomallei infection is not well understood. Thus, the aim of this study was to determine its role(s) in the virulence of B. pseudomallei pathogenesis. METHODS: A bipC TTSS-3-deficient strain of B. pseudomallei and complemented strains were generated to assess the role of BipC as a type III translocation apparatus. Human cell lines and a mouse model of melioidosis were used for in vitro and in vivo assays, respectively. RESULTS: A significant 2-fold reduction was demonstrated in the percentage of adherence, invasion, intracellular survival, and phagosomal escape of the bipC mutant. Interestingly, microscopic studies have shown that BipC was capable of delayed B. pseudomallei actin-based motility. The virulence of the mutant strain in a murine model of melioidosis demonstrated that the bipC mutant was less virulent, compared with the wild type. CONCLUSION: The results suggested that BipC possesses virulence determinants that play significant roles in host cell invasion and immune evasion.


Asunto(s)
Sistemas de Secreción Bacterianos , Burkholderia pseudomallei/patogenicidad , Proteínas de Transporte de Membrana/metabolismo , Factores de Virulencia/metabolismo , Animales , Burkholderia pseudomallei/genética , Burkholderia pseudomallei/metabolismo , Línea Celular , Modelos Animales de Enfermedad , Eliminación de Gen , Prueba de Complementación Genética , Humanos , Evasión Inmune , Melioidosis/microbiología , Melioidosis/patología , Proteínas de Transporte de Membrana/genética , Ratones Endogámicos BALB C , Virulencia , Factores de Virulencia/genética
8.
ScientificWorldJournal ; 2014: 132971, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25379514

RESUMEN

Burkholderia pseudomallei, the causative agent of melioidosis, is intrinsically resistant to many antibiotics. Ceftazidime (CAZ), the synthetic ß-lactam, is normally used as the first-line antibiotic therapy for treatment of melioidosis. However, acquired CAZ resistance can develop in vivo during treatment with CAZ, leading to mortality if therapy is not switched to a different antibiotic(s) in a timely manner. In this study, susceptibilities of 81 B. pseudomallei isolates to nine different antimicrobial agents were determined using the disk diffusion method, broth microdilution test and Etest. Highest percentage of susceptibility was demonstrated to CAZ, amoxicillin/clavulanic acid, meropenem, imipenem, and trimethoprim/sulfamethoxazole. Although these drugs demonstrated the highest percentage of susceptibility in B. pseudomallei, the overall results underline the importance of the emergence of resistance in this organism. PCR results showed that, of the 81 B. pseudomallei, six multidrug resistant (MDR) isolates carried bpeB, amrB, and BPSS1119 and penA genes. Genotyping of the isolates using random amplified polymorphic DNA analysis showed six different PCR fingerprinting patterns generated from the six MDR isolates clusters (A) and eight PCR fingerprinting patterns generated for the remaining 75 non-MDR isolates clusters (B).


Asunto(s)
Antibacterianos/farmacología , Proteínas Bacterianas/genética , Burkholderia pseudomallei/efectos de los fármacos , Burkholderia pseudomallei/genética , Proteínas de Transporte de Membrana/genética , Amoxicilina/farmacología , Proteínas Bacterianas/metabolismo , Burkholderia pseudomallei/crecimiento & desarrollo , Ácido Clavulánico/farmacología , Dermatoglifia del ADN , Farmacorresistencia Bacteriana , Expresión Génica , Humanos , Imipenem/farmacología , Malasia , Melioidosis/tratamiento farmacológico , Melioidosis/microbiología , Proteínas de Transporte de Membrana/metabolismo , Meropenem , Pruebas de Sensibilidad Microbiana , Tienamicinas/farmacología , Combinación Trimetoprim y Sulfametoxazol/farmacología
9.
Iran J Basic Med Sci ; 27(2): 214-222, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38234660

RESUMEN

Objectives: Pneumococcal cell wall (PCW) is an inflammatory component in Streptococcus pneumoniae. The cell surface proteins and the toll-like receptors (TLR) signaling response were investigated in the human lung epithelial (A549) cells inoculated with PCW of different serotypes. Materials and Methods: The presence of genes encoding these proteins was determined using polymerase chain reaction (PCR). The structure of the cell walls was analyzed by proton nuclear magnetic resonance (1H NMR). The A549 cell line was challenged with PCW extracts of different serotypes. RNA from the infected host cells was extracted and tested against a total of 84 genes associated with TLR signaling pathways (TLR 1-6 and 10) using RT2 Profiler PCR Array. Results: Cell surface proteins; ply, lytA, nanA, nanB, and cbpD genes were present in all serotypes. The distribution and structure of surface protein genes suggest behavioral changes in the molecules, contributing to the resilience of the strains to antibiotic treatment. Conclusion: TLR2 showed the highest expression, while serotypes 1, 3, and 5 induced higher TNFα and IL-1α, suggesting to be more immunogenic than the other strains tested.

10.
Gene ; 896: 148057, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38043836

RESUMEN

Colorectal cancer (CRC) is ranked as the second leading cause of mortality worldwide, mainly due to metastasis. Epithelial to mesenchymal transition (EMT) is a complex cellular process that drives CRC metastasis, regulated by changes in EMT-associated gene expression. However, while numerous genes have been identified as EMT regulators through various in vivo and in vitro studies, little is known about the genes that are differentially expressed in CRC tumour tissue and their signalling pathway in regulating EMT. Using an integration of systematic search and bioinformatic analysis, gene expression profiles of CRC tumour tissues were compared to non-tumour adjacent tissues to identify differentially expressed genes (DEGs), followed by performing systematic review on common identified DEGs. Fifty-eight common DEGs were identified from the analysis of 82 tumour tissue samples obtained from four gene expression datasets (NCBI GEO). These DEGS were then systematically searched for their roles in modulating EMT in CRC based on previously published studies. Following this, 10 common DEGs (CXCL1, CXCL8, MMP1, MMP3, MMP7, TACSTD2, VIP, HPGD, ABCG2, CLCA4) were included in this study and subsequently subjected to further bioinformatic analysis. Their roles and functions in modulating EMT in CRC were discussed in this review. This study enhances our understanding of the molecular mechanisms underlying EMT and uncovers potential candidate genes and pathways that could be targeted in CRC.


Asunto(s)
Neoplasias Colorrectales , Transición Epitelial-Mesenquimal , Humanos , Transición Epitelial-Mesenquimal/genética , Neoplasias Colorrectales/patología , Transducción de Señal/genética , Expresión Génica , Biología Computacional , Regulación Neoplásica de la Expresión Génica , Línea Celular Tumoral
11.
Artículo en Inglés | MEDLINE | ID: mdl-37773580

RESUMEN

Almost 70% of clinically used antineoplastic drugs are originated from natural products such as plants, marine organism, and microorganisms and some of them are also structurally modified natural products. The naturally occurring drugs may specifically act as inducers of selective cytotoxicity, anti-metastatic, anti-mutagenic, anti-angiogenesis, antioxidant accelerators, apoptosis inducers, autophagy inducers, and cell cycle inhibitors in cancer therapy. Precisely, several reports have demonstrated the involvement of naturally occurring anti-breast cancer drugs in regulating the expression of oncogenic and tumor suppressors associated with carcinogen metabolism and signaling pathways. Anticancer therapies based on nanotechnology have the potential to improve patient outcomes through targeted therapy, improved drug delivery, and combination therapies. This paper has reviewed the current treatment for breast cancer and the potential disadvantages of those therapies, besides the various mechanism used by naturally occurring phytochemicals to induce apoptosis in different types of breast cancer. Along with this, the contribution of nanotechnology in improving the effectiveness of anticancer drugs was also reviewed. With the development of sciences and technologies, phytochemicals derived from natural products are continuously discovered; however, the search for novel natural products as chemoprevention drugs is still ongoing, especially for the advanced stage of breast cancer. Continued research and development in this field hold great promise for advancing cancer care and improving patient outcomes.

12.
PeerJ ; 11: e15305, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37361034

RESUMEN

Background: Uropathogenic Escherichia coli (UPEC) is the predominant agent causing various categories of complicated urinary tract infections (cUTI). Although existing data reveals that UPEC harboured numerous virulence determinants to aid its survival in the urinary tract, the reason behind the occurrence of differences in the clinical severity of uninary tract infections (UTI) demonstrated by the UPEC infection is poorly understood. Therefore, the present study aims to determine the distribution of virulence determinants and antimicrobial resistance among different phylogroups of UPEC isolated from various clinical categories of cUTI and asymptomatic bacteriuria (ASB) E. coli isolates. The study will also attempt a relational analysis of the genotypic characteristics of cUTI UPEC and ASB E. coli isolates. Methods: A total of 141 UPEC isolates from cUTI and 160 ASB E. coli isolates were obtained from Universiti Malaya Medical Centre (UMMC). Phylogrouping and the occurrence of virulence genes were investigated using polymerase chain reaction (PCR). Antimicrobial susceptibility of the isolates to different classes of antibiotics was determined using the Kirby Bauer Disc Diffusion method. Results: The cUTI isolates were distributed differentially among both Extraintestinal Pathogenic E. coli (ExPEC) and non-ExPEC phylogroups. Phylogroup B2 isolates were observed to possess the highest average aggregative virulence score (7.17), a probable representation of the capability to cause severe disease. Approximately 50% of the cUTI isolates tested in this study were multidrug resistant against common antibiotics used to treat UTI. Analysis of the occurrence of virulence genes among different cUTI categories demonstrated that UPEC isolates of pyelonephritis and urosepsis were highly virulent and had the highest average aggregative virulence scores of 7.80 and 6.89 respectively, compared to other clinical categories. Relational analysis of the occurrence of phylogroups and virulence determinants of UPEC and ASB E. coli isolates showed that 46.1% of UPEC and 34.3% of ASB E. coli from both categories were distributed in phylogroup B2 and had the highest average aggregative virulence score of 7.17 and 5.37, respectively. The data suggest that UPEC isolates which carry virulence genes from all four virulence genes groups studied (adhesions, iron uptake systems, toxins and capsule synthesis) and isolates from phylogroup B2 specifically could predispose to severe UTI involving the upper urinary tract. Therefore, specific analysis of the genotypic characteristics of UPEC could be further explored by incorporating the combination of virulence genes as a prognostic marker for predicting disease severity, in an attempt to propose a more evidence driven treatment decision-making for all UTI patients. This will go a long way in enhancing favourable therapeutic outcomes and reducing the antimicrobial resistance burden among UTI patients.


Asunto(s)
Bacteriuria , Infecciones Urinarias , Escherichia coli Uropatógena , Humanos , Bacteriuria/tratamiento farmacológico , Escherichia coli Uropatógena/genética , Infecciones Urinarias/tratamiento farmacológico , Factores de Virulencia/genética , Antibacterianos/farmacología
13.
PLoS One ; 17(5): e0267296, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35522610

RESUMEN

Asymptomatic bacteriuria (ASB) caused by Escherichia coli (E. coli) is a significant condition associated with pregnancy and is considered as prognostic for the development of symptomatic urinary tract infection (UTI). However, treating all ASB increases the use of antibiotics and leads to the development of multidrug resistance (MDR). Therefore, this study aimed to identify the distribution of UPEC associated virulence genes and antibiotic susceptibility among phylogroups of E. coli isolated from ASB in pregnancy. Moreover, the gene expression of selected virulence genes was also compared among two E. coli isolates (with different pathogenic potential) to determine its pathogenicity. One hundred and sixty E. coli isolates from midstream urine samples of pregnant women with ASB were subjected to PCR-based detection for its phylogroups and virulence genes. The antibiotic susceptibility of isolated strains was determined by the disc diffusion method. Expression of the virulence genes were determined through microarray analysis and quantitative Real-Time PCR. The prevalence of ASB in this study was 16.1%. Within ASB isolates, the occurrence of phylogroup B2 was the highest, and isolates from this group harboured most of the virulence genes studied. Overall, the most identified virulence genes among all phylogroups in descending order were fimH, chuA, kpsMTII, usp, fyuA, hlyA, iroN, cnf, papC, sfa, ompT, and sat. In this study, higher resistance to antibiotics was observed for ampicillin (77.5%), amoxicillin-clavulanate (54.4%), trimethoprim-sulfamethoxazole (46.9%) and amikacin (43.8%) compared to the other tested antibiotics and 51.9% of the tested isolates were MDR. Furthermore, hierarchical clustering and gene expression analysis demonstrated extreme polarization of pathogenic potential of E. coli causing ASB in pregnancy necessitating the need for bacterial isolate focused approach towards treatment of ASB.


Asunto(s)
Bacteriuria , Infecciones por Escherichia coli , Infecciones Urinarias , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Bacteriuria/diagnóstico , Bacteriuria/tratamiento farmacológico , Bacteriuria/microbiología , Escherichia coli , Infecciones por Escherichia coli/diagnóstico , Infecciones por Escherichia coli/tratamiento farmacológico , Infecciones por Escherichia coli/epidemiología , Femenino , Humanos , Masculino , Embarazo , Infecciones Urinarias/diagnóstico , Infecciones Urinarias/tratamiento farmacológico , Infecciones Urinarias/microbiología , Virulencia/genética , Factores de Virulencia/genética
14.
Pathogens ; 12(1)2022 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-36678359

RESUMEN

Melioidosis, also known as Whitmore's disease, is a potentially fatal infection caused by the Gram-negative bacteria Burkholderia pseudomallei with a mortality rate of 10-50%. The condition is a "glanders-like" illness prevalent in Southeast Asian and Northern Australian regions and can affect humans, animals, and sometimes plants. Melioidosis received the epithet "the great mimicker" owing to its vast spectrum of non-specific clinical manifestations, such as localised abscesses, septicaemia, pneumonia, septic arthritis, osteomyelitis, and encephalomyelitis, which often lead to misdiagnosis and ineffective treatment. To date, antibiotics remain the backbone of melioidosis treatment, which includes intravenous therapy with ceftazidime or meropenem, followed by oral therapy with TMP-SMX or amoxicillin/clavulanic acid and supported by adjunctive treatment. However, bacteria have developed resistance to a series of antibiotics, including clinically significant ones, during treatment. Therefore, phage therapy has gained unprecedented interest and has been proposed as an alternative treatment. Although no effective phage therapy has been published, the findings of experimental phage therapies suggest that the concept could be feasible. This article reviews the benefits and limitations of antibiotics and phage therapy in terms of established regimens, bacterial resistance, host specificity, and biofilm degradation.

15.
Front Vet Sci ; 9: 1056723, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36590813

RESUMEN

The One Health concept was initiated to promote the integration of human, animal, and environmental ecosystems into healthcare to ensure effective control and the sustainable governance of multifaceted health matters. Climate change, deforestation, and rigorous farming disrupt the environment, which serves as the natural habitat for many animals and microbes, increasing the likelihood of disease transmission between humans and animals. Melioidosis (neglected tropical diseases) and glanders are of humans and animals caused by the gram-negative bacteria Burkholderia pseudomallei and its close relative Burkholderia mallei, respectively. In Malaysia, although melioidosis is endemic, it is not a notifiable disease. Hence, the true prevalence of melioidosis in Malaysia is unknown and varies in different regions of the country, with reported hotspots associated with agriculture-related activities. To date, no incidence of human glanders has been reported in Malaysia, although occupational exposure for equine handlers and veterinary professionals remains a concern. Additionally, antibiotics are widely used in the healthcare and veterinary sectors to treat or prevent B. pseudomallei and B. mallei infections, leading to the emergence of resistance in B. pseudomallei. Lack of surveillance, research, assessment, and management of glanders and melioidosis is a major issue in Malaysia. Proper assessment systems and cross-discipline cooperation are vital to recognize and manage both diseases. Experts and practitioners from clinical and veterinary disciplines, environmentalists, law enforcement, policymakers, researchers, local communities, and other experts need to communicate, collaborate, and coordinate activities to fill the knowledge gap on glanders and melioidosis to reduce morbidity and mortality rates in the country. This review aims to define the organizational and functional characteristics of One Health surveillance approaches for glanders and melioidosis from a Malaysian perspective.

16.
Antibiotics (Basel) ; 11(11)2022 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-36421313

RESUMEN

Non-carbapenemase-producing carbapenem-resistant Klebsiella pneumoniae (NC-CRKP) confers carbapenem resistance through a combination of chromosomal mutations and acquired non-carbapenemase resistance mechanisms. In this study, we aimed to evaluate the clinical and molecular profiles of NC-CRKP isolated from patients in a tertiary teaching hospital in Malaysia from January 2013 to October 2019. During the study period, 54 NC-CRKP-infected/colonised patients' isolates were obtained. Clinical parameters were assessed in 52 patients. The all-cause in-hospital mortality rate among NC-CRKP patients was 46.2% (24/52). Twenty-three (44.2%) patients were infected, while others were colonised. Based on the Charlson Comorbidity Index (CCI) score, 92.3% (48/52) of the infected/colonised patients had a score of ≥ 1. Resistance genes found among the 54 NC-CRKP isolates were blaTEM, blaSHV, blaCTX-M, blaOXA, and blaDHA. Porin loss was detected in 25/54 (46.3%) strains. None of the isolated strains conferred carbapenem resistance through the efflux pumps system. In conclusion, only 25/54 (46.3%) NC-CRKP conferred carbapenem resistance through a combination of porin loss and the acquisition of non-carbapenemase resistance mechanisms. The carbapenem resistance mechanisms for the remaining strains (53.7%) should be further investigated as rapid identification and distinction of the NC-CRKP mechanisms enable optimal treatment and infection control efforts.

17.
Transbound Emerg Dis ; 69(2): 477-484, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33506647

RESUMEN

Burkholderia pseudomallei, a Gram-negative bacterial pathogen that causes melioidosis, is of public health importance in endemic areas including Malaysia. An investigation of the molecular epidemiology links of B. pseudomallei would contribute to better understanding of the clonal relationships, transmission dynamics and evolutionary change. Multilocus sequence typing (MLST) of 45 clinical B. pseudomallei isolates collected from sporadic melioidosis cases in Malaysia was performed. In addition, a total of 449 B. pseudomallei Malaysian strains submitted to the MLST database from 1964 until 2019 were included in the temporal analysis to determine the endemic sequence types (STs), emergence and re-emergence of ST(s). In addition, strain-specific distribution was evaluated using BURST tool. Genotyping of 45 clinical strains was resolved into 12 STs, and the majority were affiliated with ST46 (n = 11) and ST1342 (n = 7). Concomitantly, ST46 was the most prevalent ST in Malaysia, which was first reported in 1964. All the Malaysian B. pseudomallei strains were resolved into 76 different STs with 36 of them uniquely present only in Malaysia. ST1342 was most closely related to ST1034, in which both STs were unique to Malaysia and first isolated from soil samples in Pahang, a state in Malaysia. The present study revealed a high diversity of B. pseudomallei in Malaysia. Localized evolution giving rise to the emergence of new STs was observed, suggesting that host and environmental factors play a crucial role in the evolutionary changes in B. pseudomallei.


Asunto(s)
Burkholderia pseudomallei , Melioidosis , Animales , Burkholderia pseudomallei/genética , Malasia/epidemiología , Melioidosis/epidemiología , Melioidosis/microbiología , Melioidosis/veterinaria , Tipificación de Secuencias Multilocus/veterinaria , Filogenia
18.
Electrophoresis ; 32(2): 310-20, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21254130

RESUMEN

Bacterial secreted proteins are known to be involved in virulence and may mediate important host-pathogen interactions. In this study, when the stationary phase culture supernatant of Burkholderia pseudomallei was subjected to 2-DE, 113 protein spots were detected. Fifty-four of the secreted proteins, which included metabolic enzymes, transcription/translation regulators, potential virulence factors, chaperones, transport regulators, and hypothetical proteins, were identified using MS and database search. Twelve of these proteins were apparently reactive to antisera of mice that were immunised with B. pseudomallei secreted proteins. These proteins might be excellent candidates to be used as diagnostic markers or putative candidate vaccines against B. pseudomallei infections.


Asunto(s)
Proteínas Bacterianas/inmunología , Burkholderia pseudomallei/inmunología , Animales , Proteínas Bacterianas/análisis , Proteínas Bacterianas/metabolismo , Burkholderia pseudomallei/metabolismo , Masculino , Ratones , Ratones Endogámicos BALB C , Proteoma/análisis , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
19.
Front Microbiol ; 12: 718774, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34759896

RESUMEN

On a global scale, antimicrobial resistance (AMR) is recognized as a One Health challenge due to the continual and increased development and distribution of resistant microbes and genes among humans, animals, and the environment. These sectors contribute to the increase in AMR, as antibiotics are widely used in healthcare to treat or prevent bacterial infection; as growth enhancers, therapeutics and metaphylactics in animal husbandry; and transmitted in the environment through irrigation using wastewater or inappropriate disposal and treatment of human and agricultural waste. However, there is a major drawback in terms of the lack of research assessing the coexistence of AMR in these sectors. Extensive research highlighted food-animal manufacture structures that are likely to harbor reservoirs or promote transmission of AMR, in addition to increasing human colonization with AMR commensal bacteria. Numerous antibiotic stewardship policies have been designed and implemented in medical practices and animal husbandry in high- and middle-income countries. However, research concentrating on high-income settings, attitudes, emotions, and beliefs on the utilization of antimicrobials remain underexplored in lower- and middle-income countries such as Malaysia. Microbiological, epidemiological, and social science exploration are required at community and farming across the One Health range to fill huge gaps in information and knowledge of AMR. Manipulating human activities and character associated with antibiotics is a multifaceted progression that includes elements like knowledge, social behavior, attitudes, approaches, social standards, socioeconomic settings, peer pressure, experiences, and biophysical environment. Therefore, understanding these aspects in the utilization of antimicrobial drugs among the different sectors is essential to develop and implement policies to curb AMR development and transmission that overarch all sectors within the One Health consortium in Malaysia.

20.
Iran J Basic Med Sci ; 24(11): 1538-1545, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35317109

RESUMEN

Objectives: To investigate the potential anti-breast cancer activity of zerumbone in regulating apoptotic mediators and cytokines in comparison with paclitaxel (positive control). Materials and Methods: In this study, assays such as viability, apoptosis, reactive oxygen species, cell cycle, DNA fragmentation, and cytokines were carried out on MCF-7 cells after treatment with zerumbone and paclitaxel. Results: The results showed that zerumbone demonstrated a higher (18-fold) IC50 value (126.7 µg/ml) than paclitaxel (7.29 µg/ml) in order to suppress proliferation and induce cell death of MCF-7. The cell cycle arrest at the G0/G1 phase and excessive intracellular ROS production during the in vitro zerumbone treatment indicated occurrence of apoptotic cell death although nuclear DNA fragmentation was not observed. The flow cytometer analysis of treated cells revealed secretion of proinflammatory cytokines suggesting the potential immunomodulatory activity of zerumbone. Conclusion: Although, zerumbone exhibited a higher IC50 value compared with paclitaxel yet its anticancer activity against MCF-7 cells is still parallel to paclitaxel hence zerumbone has the potential to be an antineoplastic agent in the treatment of breast cancer especially the luminal type A.

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