Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 28
Filtrar
Más filtros













Base de datos
Intervalo de año de publicación
2.
iScience ; 27(3): 109043, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38375225

RESUMEN

This study investigated the potential of using SARS-CoV-2 viral concentrations in dust as an additional surveillance tool for early detection and monitoring of COVID-19 transmission. Dust samples were collected from 8 public locations in 16 districts of Bangkok, Thailand, from June to August 2021. SARS-CoV-2 RNA concentrations in dust were quantified, and their correlation with community case incidence was assessed. Our findings revealed a positive correlation between viral concentrations detected in dust and the relative risk of COVID-19. The highest risk was observed with no delay (0-day lag), and this risk gradually decreased as the lag time increased. We observed an overall decline in viral concentrations in public places during lockdown, closely associated with reduced human mobility. The effective reproduction number for COVID-19 transmission remained above one throughout the study period, suggesting that transmission may persist in locations beyond public areas even after the lockdown measures were in place.

4.
iScience ; 26(7): 107215, 2023 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-37496674

RESUMEN

Developing an effective therapy to overcome carbapenemase-positive Klebsiella pneumoniae (CPKp) is an important therapeutic challenge that must be addressed urgently. Here, we explored a Ca-EDTA combination with aztreonam or ceftazidime-avibactam in vitro and in vivo against diverse CPKp clinical isolates. The synergy testing of this study demonstrated that novel aztreonam-Ca-EDTA or ceftazidime-avibactam-Ca-EDTA combination was significantly effective in eliminating planktonic and mature biofilms in vitro, as well as eradicating CPKp infections in vivo. Both combinations revealed significant therapeutic efficacies in reducing bacterial load in internal organs and protecting treated mice from mortality. Conclusively, this is the first in vitro and in vivo study to demonstrate that novel aztreonam-Ca-EDTA or ceftazidime-avibactam-Ca-EDTA combinations provide favorable efficacy and safety for successful eradication of carbapenemase-producing Klebsiella pneumoniae planktonic and biofilm infections.

5.
iScience ; 26(7): 107019, 2023 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-37351501

RESUMEN

Equitable SARS-CoV-2 surveillance in low-resource communities lacking centralized sewers is critical as wastewater-based epidemiology (WBE) progresses. However, large-scale studies on SARS-CoV-2 detection in wastewater from low-and middle-income countries is limited because of economic and technical reasons. In this study, wastewater samples were collected twice a month from 186 urban and rural subdistricts in nine provinces of Thailand mostly having decentralized and non-sewered sanitation infrastructure and analyzed for SARS-CoV-2 RNA variants using allele-specific RT-qPCR. Wastewater SARS-CoV-2 RNA concentration was used to estimate the real-time incidence and time-varying effective reproduction number (Re). Results showed an increase in SARS-CoV-2 RNA concentrations in wastewater from urban and rural areas 14-20 days earlier than infected individuals were officially reported. It also showed that community/food markets were "hot spots" for infected people. This approach offers an opportunity for early detection of transmission surges, allowing preparedness and potentially mitigating significant outbreaks at both spatial and temporal scales.

6.
J Bioinform Comput Biol ; 21(2): 2350006, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-37120707

RESUMEN

Antimicrobial resistance is a major public health concern. Antimicrobial peptides (AMPs) are one of the host defense mechanisms responding efficiently against multidrug-resistant microbes. Since the process of screening AMPs from a large number of peptides is still high-priced and time-consuming, the development of a precise and rapid computer-aided tool is essential for preliminary AMPs selection ahead of laboratory experiments. In this study, we proposed AMPs recognition models using a new peptide encoding method called amino acid index weight (AAIW). Four AMPs recognition models including antimicrobial, antibacterial, antiviral, and antifungal were trained based on datasets combined from the DRAMP and other published databases. These models achieved high performance compared to the preceding AMPs recognition models when evaluated on two independent test sets. All four models yielded over 93% in accuracy and 0.87 in Matthew's correlation coefficient (MCC). An online AMPs recognition server is accessible at https://amppred-aaiw.com.


Asunto(s)
Antiinfecciosos , Péptidos Catiónicos Antimicrobianos , Péptidos Catiónicos Antimicrobianos/farmacología , Péptidos Catiónicos Antimicrobianos/química , Péptidos Antimicrobianos , Antiinfecciosos/farmacología , Antiinfecciosos/química , Antibacterianos , Antifúngicos
7.
Sci Total Environ ; 858(Pt 1): 159816, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36461562

RESUMEN

The monkeypox virus is excreted in the feces of infected individuals. Therefore, there is an interest in using viral load detection in wastewater for sentinel early surveillance at a community level and as a complementary approach to syndromic surveillance. We collected wastewater from 63 sewered and non-sewered locations in Bangkok city center between May and August 2022. Monkeypox viral DNA copy numbers were quantified using real-time polymerase chain reaction (PCR) and confirmed positive by Sanger sequencing. Monkeypox viral DNA was first detected in wastewater from the second week of June 2022, with a mean copy number of 16.4 copies/ml (n = 3). From the first week of July, the number of viral DNA copies increased to a mean copy number of 45.92 copies/ml. Positive samples were Sanger sequenced and confirmed the presence of the monkeypox virus. Our study is the first to detect monkeypox viral DNA in wastewater from various locations within Thailand. Results suggest that this could be a complementary source for detecting viral DNA and predicting upcoming outbreaks.


Asunto(s)
Mpox , Humanos , Aguas Residuales , ADN Viral , Tailandia , Heces
8.
Sci Rep ; 12(1): 12939, 2022 07 28.
Artículo en Inglés | MEDLINE | ID: mdl-35902639

RESUMEN

The global prevalence of colistin-resistant Klebsiella pneumoniae (ColRkp) facilitated by chromosomal and plasmid-mediated Ara4N or PEtN-remodeled LPS alterations has steadily increased with increased colistin usage for treating carbapenem-resistant K. pneumoniae (CRkp). Our study demonstrated the rising trend of ColRkp showing extensively and pandrug-resistant characteristics among CRkp, with a prevalence of 28.5%, which was mediated by chromosomal mgrB, pmrB, or phoQ mutations (91.5%), and plasmid-mediated mcr-1.1, mcr-8.1, mcr-8.2 alone or in conjunction with R256G PmrB (8.5%). Several genetic alterations in mgrB (85.1%) with increased expressions of Ara4N-related phoPQ and pmrK were critical for establishing colistin resistance in our isolates. In this study, we discovered the significant associations between extensively drug-resistant bacteria (XDR) and pandrug-resistant bacteria (PDR) ColRkp in terms of moderate, weak or no biofilm-producing abilities, and altered expressions of virulence factors. These ColRkp would therefore be very challenging to treat, emphasizing for innovative therapy to combat these infections. Regardless of the underlying colistin-resistant mechanisms, colistin-EDTA combination therapy in this study produced potent synergistic effects in both in vitro and in vivo murine bacteremia, with no ColRkp regrowth and improved animal survival, implying the significance of colistin-EDTA combination therapy as systemic therapy for unlocking colistin resistance in ColRkp-associated bacteremia.


Asunto(s)
Bacteriemia , Enterobacteriaceae Resistentes a los Carbapenémicos , Infecciones por Klebsiella , Animales , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Bacteriemia/tratamiento farmacológico , Proteínas Bacterianas/metabolismo , Enterobacteriaceae Resistentes a los Carbapenémicos/genética , Carbapenémicos/farmacología , Carbapenémicos/uso terapéutico , Colistina/farmacología , Colistina/uso terapéutico , Farmacorresistencia Bacteriana/genética , Ácido Edético/farmacología , Infecciones por Klebsiella/tratamiento farmacológico , Infecciones por Klebsiella/epidemiología , Infecciones por Klebsiella/microbiología , Klebsiella pneumoniae , Ratones , Pruebas de Sensibilidad Microbiana , Prevalencia
9.
Sci Rep ; 12(1): 13140, 2022 07 30.
Artículo en Inglés | MEDLINE | ID: mdl-35907887

RESUMEN

Snakebite, classified by World Health Organization as a neglected tropical disease, causes more than 100,000 deaths and 2 million injuries per year. Currently, available antivenoms do not bind with strong specificity to target toxins, which means that severe complications can still occur despite treatment. Moreover, the cost of antivenom is expensive. Knowledge of venom compositions is fundamental for producing a specific antivenom that has high effectiveness, low side effects, and ease of manufacture. With advances in mass spectrometry techniques, venom proteomes can now be analyzed in great depth at high efficiency. However, these techniques require genomic and transcriptomic data for interpreting mass spectrometry data. This study aims to establish and incorporate genomics, transcriptomics, and proteomics data to study venomics of a venomous snake, Daboia siamensis. Multiple proteins that have not been reported as venom components of this snake such as hyaluronidase-1, phospholipase B, and waprin were discovered. Thus, multi-omics data are advantageous for venomics studies. These findings will be valuable not only for antivenom production but also for the development of novel therapeutics.


Asunto(s)
Daboia , Mordeduras de Serpientes , Animales , Antivenenos/química , Proteoma/análisis , Proteómica/métodos , Mordeduras de Serpientes/tratamiento farmacológico , Serpientes , Ponzoñas
10.
Sci Rep ; 12(1): 11390, 2022 07 06.
Artículo en Inglés | MEDLINE | ID: mdl-35794134

RESUMEN

Overcoming colistin-resistant Acinetobacter baumannii (CoR-AB) has become a major concern due to the lack of effective antibiotics. This study aimed to explore the prevalence of CoR-AB clinical isolates in Thailand, their mechanisms of resistance, and test the efficacy of colistin plus sulbactam against CoR-AB isolates. The colistin resistance rate among carbapenem-resistant A. baumannii was 15.14%. The mcr gene or its variants were not detected in CoR-AB isolates by PCR screening. The lipid A mass spectra of CoR-AB isolates showed the additional [M-H]- ion peak at m/z = 2034 that correlated to the phosphoethanolamine (pEtN) addition to lipid A (N = 27/30). The important amino acid substitutions were found at position S14P, A138T, A227V in PmrB that are associated with overexpression of the pEtN transferase (PmrC) and contributed the pEtN addition. The lipopolysacccharide production genes (lpxACD) were not related to lipid A mass spectra. A colistin plus sulbactam combination exhibited the synergy rate at 86.7% against CoR-AB isolates compare to sulbactam (85.89% resistance) or colistin (15.14% resistance) alone. The excellent synergistic activity of colistin plus sulbactam combination has the potential for the treatment of CoR-AB infections.


Asunto(s)
Infecciones por Acinetobacter , Acinetobacter baumannii , Infecciones por Acinetobacter/tratamiento farmacológico , Acinetobacter baumannii/genética , Acinetobacter baumannii/metabolismo , Colistina/uso terapéutico , Etanolaminas , Humanos , Lípido A/metabolismo , Pruebas de Sensibilidad Microbiana , Fosfatidiletanolaminas/metabolismo , Sulbactam/farmacología , Sulbactam/uso terapéutico
11.
J Proteomics ; 259: 104559, 2022 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-35283353

RESUMEN

This study focuses on comprehensive characterization of the venom proteome of the beaked sea snake (Hydrophis schistosus) from Songkhla Lake, Thailand. H. schistosus can be considered as the deadliest sea snake commonly found in the Pacific and Indian oceans. Their envenomation causes muscular paralysis and rhabdomyolysis. To develop effective treatment for this snakebite, it is necessary to understand the detailed venom composition. In this study, multiple mass spectrometry-based approaches were employed. Bottom-up proteomics revealed that tryptic digestion in-solution provided a higher number of toxin proteins identified and a larger sequence coverage, compared to in-gel digestion. In addition, a venom gland transcriptome-derived database was constructed and used as a reference, which 43 known and novel toxin proteins were identified using this database and the UniProtKB. Three-finger toxin and phospholipase A2 were shown to be top two most abundant protein families. Minor compositions included other toxin families and a number of non-toxin proteins. Moreover, a hybrid de novo sequencing was performed to enhance identification of the small proteins/peptides. Using non-digested samples, there were 46 predicted toxin peptides. The finding from this study could lead to a better understanding in pathological effects of the snakebite and the future development of effective antivenoms. SIGNIFICANCE: This study provides a better understanding of the venom proteome composition of the beaked sea snake (H. schistosus) found in the Gulf of Thailand, using a combination of different sample preparation techniques, Serpentes protein database searching, transcriptome-derived protein database searching, and a hybrid de novo peptide sequencing strategy. It revealed 13 toxin protein families and novel proteins in the beaked sea snake venom including new species of phospholipase A2s (PLA2s) and three-finger toxins (3FTxs). It could serve as a basis for the development of snakebite treatments and for the discovery of novel pharmaceutical drugs from the toxin peptides.


Asunto(s)
Hydrophiidae , Mordeduras de Serpientes , Toxinas Biológicas , Animales , Venenos Elapídicos/química , Hydrophiidae/metabolismo , Lagos , Fosfolipasas A2/metabolismo , Proteoma/metabolismo , Proteómica/métodos , Tailandia
12.
Sci Rep ; 11(1): 21659, 2021 11 04.
Artículo en Inglés | MEDLINE | ID: mdl-34737332

RESUMEN

The global rapid emergence of azithromycin/ceftriaxone resistant Neisseria gonorrhoeae threatens current recommend azithromycin/ceftriaxone dual therapy for gonorrhea to ensure effective treatment. Here, we identified the first two N. gonorrhoeae isolates with decreased ceftriaxone susceptibility in Thailand. Among 134 N. gonorrhoeae isolates collected from Thai Red Cross Anonymous Clinic, Bangkok, two isolates (NG-083 and NG-091) from urethral swab in male heterosexual patients had reduced susceptibility to ceftriaxone (MICs of 0.125 mg/L). Both were multidrug resistant and strong biofilm producers with ceftriaxone tolerance (MBEC > 128 mg/L). NG-083 and NG-091 remained susceptible to azithromycin (MIC of 1 mg/L and 0.5 mg/L, respectively). Reduced susceptibility to ceftriaxone was associated with alterations in PBP2, PBP1, PorB, MtrR, and mtrR promoter region. NG-083 belonged to sequence type (ST) 7235 and NG-091 has new allele number of tbpB with new ST. Molecular docking revealed ceftriaxone weakly occupied the active site of mosaic XXXIV penicillin-binding protein 2 variant in both isolates. Molecular epidemiology results revealed that both isolates display similarities with isolates from UK, USA, and The Netherlands. These first two genetically related gonococcal isolates with decreased ceftriaxone susceptibility heralds the threat of treatment failure in Thailand, and importance of careful surveillance.


Asunto(s)
Ceftriaxona/farmacología , Farmacorresistencia Bacteriana/efectos de los fármacos , Gonorrea/epidemiología , Adulto , Antibacterianos/farmacología , Azitromicina/farmacología , Cefixima/farmacología , Ceftriaxona/metabolismo , Farmacorresistencia Bacteriana/genética , Resistencia a Múltiples Medicamentos/genética , Heterosexualidad , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Simulación del Acoplamiento Molecular , Neisseria gonorrhoeae/genética , Neisseria gonorrhoeae/patogenicidad , Tailandia/epidemiología
13.
Sci Rep ; 11(1): 21676, 2021 11 04.
Artículo en Inglés | MEDLINE | ID: mdl-34737361

RESUMEN

Development of an effective therapy to overcome colistin resistance in Klebsiella pneumoniae, a common pathogen causing catheter-related biofilm infections in vascular catheters, has become a serious therapeutic challenge that must be addressed urgently. Although colistin and EDTA have successful roles for eradicating biofilms, no in vitro and in vivo studies have investigated their efficacy in catheter-related biofilm infections of colistin-resistant K. pneumoniae. In this study, colistin resistance was significantly reversed in both planktonic and mature biofilms of colistin-resistant K. pneumoniae by a combination of colistin (0.25-1 µg/ml) with EDTA (12 mg/ml). This novel colistin-EDTA combination was also demonstrated to have potent efficacy in eradicating colistin-resistant K. pneumoniae catheter-related biofilm infections, and eliminating the risk of recurrence in vivo. Furthermore, this study revealed significant therapeutic efficacy of colistin-EDTA combination in reducing bacterial load in internal organs, lowering serum creatinine, and protecting treated mice from mortality. Altered in vivo expression of different virulence genes indicate bacterial adaptive responses to survive in hostile environments under different treatments. According to these data discovered in this study, a novel colistin-EDTA combination provides favorable efficacy and safety for successful eradication of colistin-resistant K. pneumonia catheter-related biofilm infections.


Asunto(s)
Colistina/uso terapéutico , Ácido Edético/uso terapéutico , Klebsiella pneumoniae/efectos de los fármacos , Animales , Antibacterianos/uso terapéutico , Biopelículas/efectos de los fármacos , Infecciones Relacionadas con Catéteres/tratamiento farmacológico , Catéteres/microbiología , Colistina/metabolismo , Combinación de Medicamentos , Farmacorresistencia Bacteriana/efectos de los fármacos , Femenino , Infecciones por Klebsiella/microbiología , Klebsiella pneumoniae/patogenicidad , Ratones , Ratones Endogámicos C57BL , Pruebas de Sensibilidad Microbiana , Virulencia
14.
Int J Infect Dis ; 108: 296-299, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33989774

RESUMEN

INTRODUCTION: SARS-CoV-2 RNA is excreted in feces of most patients, therefore viral load in wastewater can be used as a surveillance tool to develop an early warning system to help and manage future pandemics. METHODS: We collected wastewater from 24 random locations at Bangkok city center and 26 nearby suburbs from July to December 2020. SARS-CoV-2 RNA copy numbers were measured using real-time polymerase chain reaction (PCR). RESULTS: SARS-CoV-2 RNA was detected in wastewater from both the city center and suburbs. Except for July, there were no significant differences in copy numbers between the city center and suburbs. Between October and November, a sharp rise in copy number was observed in both places followed by two to three times increase in December, related to SARS-CoV-2 cases reported for same month. CONCLUSIONS: Our study provided the first dataset related to SARS-CoV-2 viral RNA in the wastewater of Bangkok. Our results suggest that wastewater could be used as a complementary source for detecting viral RNA and predicting upcoming outbreaks and waves.


Asunto(s)
COVID-19 , Aguas Residuales , Humanos , ARN Viral/genética , SARS-CoV-2 , Tailandia
16.
iScience ; 23(9): 101530, 2020 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-33083760

RESUMEN

Signaling through stimulator of interferon genes (STING) leads to the production of type I interferons (IFN-Is) and inflammatory cytokines. A gain-of-function mutation in STING was identified in an autoinflammatory disease (STING-associated vasculopathy with onset in infancy; SAVI). The expression of cyclic GMP-AMP, DNA-activated cGAS-STING pathway, increased in a proportion of patients with SLE. The STING signaling pathway may be a candidate for targeted therapy in SLE. Here, we demonstrated that disruption of STING signaling ameliorated lupus development in Fcgr2b-deficient mice. Activation of STING promoted maturation of conventional dendritic cells and differentiation of plasmacytoid dendritic cells via LYN interaction and phosphorylation. The inhibition of LYN decreased the differentiation of STING-activated dendritic cells. Adoptive transfer of STING-activated bone marrow-derived dendritic cells into the FCGR2B and STING double-deficiency mice restored lupus phenotypes. These findings provide evidence that the inhibition of STING signaling may be a candidate targeted treatment for a subset of patients with SLE.

17.
Front Immunol ; 11: 1101, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32582187

RESUMEN

The levels of interferon-alpha are high in the serum and synovial fluid of rheumatoid arthritis (RA) patients. Activation of the stimulator of type I interferon genes (STING) mediates the productions of type I interferon and promotes chronic inflammation. STING plays a significant role in autoimmune lupus mice. However, the function of STING in collagen-induced arthritis (CIA) model has never been described. This study aimed to test the function of STING in CIA. The Sting-deficient mice developed arthritis comparable to WT mice. The levels of anti-collagen antibody from Sting-deficient mice were significantly higher than the WT mice. The B cells derived from Sting-deficient mice showed better survival than WT mice in response to the B cell receptor (BCR) stimulation. Activation of STING also induced B cell death, especially in activated B cells. This study demonstrated that the inhibition of STING promotes anti-collagen antibodies and B cell survival, which suggested that STING acts as a negative regulator of B cell function in the CIA model.


Asunto(s)
Artritis Experimental/inmunología , Artritis Reumatoide/inmunología , Autoanticuerpos/inmunología , Linfocitos B/inmunología , Proteínas de la Membrana/inmunología , Animales , Formación de Anticuerpos/inmunología , Autoantígenos/inmunología , Colágeno Tipo II/inmunología , Ratones
18.
Ann Clin Microbiol Antimicrob ; 19(1): 8, 2020 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-32169075

RESUMEN

Treatment of infections by Pseudomonas aeruginosa forming biofilms after antimicrobial testing on planktonic bacteria can result in substantial failure. Therefore, we offer a robust and simple experimental platform to test the impact of antimicrobials on biofilms. Antibiotic response patterns varied uniquely within biofilm formation capacity and minimal biofilm eradication concentrations (MBECs) has a significantly better discriminatory power than minimum inhibitory concentrations (MICs) to differentiate the overall efficiency of antibiotics to eradicate biofilm. Our resazurin-based 96-well-plate platform is able to emulate bacterial responses to antibiotics under biofilm conditions in a fast, simple, and cost-effective screening method adaptable to automation, and warrants trials in the clinic.


Asunto(s)
Antibacterianos/farmacología , Biopelículas/efectos de los fármacos , Pruebas de Sensibilidad Microbiana/métodos , Infecciones por Pseudomonas , Pseudomonas aeruginosa/efectos de los fármacos , Humanos , Infecciones por Pseudomonas/microbiología
19.
Bioinformatics ; 35(24): 5313-5314, 2019 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-31318409

RESUMEN

SUMMARY: Identification of the amino-acid motifs in proteins that are targeted for post-translational modifications (PTMs) is of great importance in understanding regulatory networks. Information about targeted motifs can be derived from mass spectrometry data that identify peptides containing specific PTMs such as phosphorylation, ubiquitylation and acetylation. Comparison of input data against a standardized 'background' set allows identification of over- and under-represented amino acids surrounding the modified site. Conventionally, calculation of targeted motifs assumes a random background distribution of amino acids surrounding the modified position. However, we show that probabilities of amino acids depend on (i) the type of the modification and (ii) their positions relative to the modified site. Thus, software that identifies such over- and under-represented amino acids should make appropriate adjustments for these effects. Here we present a new program, PTM-Logo, that generates representations of these amino acid preferences ('logos') based on position-specific amino-acid probability backgrounds calculated either from user-input data or curated databases. AVAILABILITY AND IMPLEMENTATION: PTM-Logo is freely available online at http://sysbio.chula.ac.th/PTMLogo/ or https://hpcwebapps.cit.nih.gov/PTMLogo/. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Asunto(s)
Procesamiento Proteico-Postraduccional , Programas Informáticos , Aminoácidos , Posición Específica de Matrices de Puntuación , Proteínas
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA