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1.
Ann Hepatobiliary Pancreat Surg ; 28(1): 59-69, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38049111

RESUMEN

Backgrounds/Aims: Pancreaticoduodenectomy (PD) is the only radical treatment for periampullary malignancies. Superior mesenteric artery (SMA) first approach combined with total meso-pancreas (MP) excision was conducted to improve the oncological results. There has not been any previous research of a technique that combines the SMA first approach and total MP excision with a detailed description of the MP macroscopical shape. Methods: We prospectively assessed 77 patients with periampullary malignancies between October 2020 and March 2022 (18 months). All patients had undergone PD with SMA first approach combined total MP excision. The perioperative indications, clinical data, intra-operative index, R0 resection rate of postoperative pathological specimens (especially mesopancreatic margin), postoperative complications, and follow-up results were evaluated. Results: The median operative time was 289.6 min (178-540 min), the median intraoperative blood loss was 209 mL (30-1,600 mL). Microscopically, there were 19 (24.7%) cases with metastatic MP, and five cases (6.5%) with R1-resection of the MP. The number of lymph nodes (LNs) harvested and metastatic LNs were 27.2 (maximum was 74) and 1.8 (maximum was 16), respectively. Some (46.8%) patients had pancreatic fistula, but mostly in grade A, with 7 patients (9.1%) who required re-operations. Some 18.2% of cases developed postoperative refractory diarrhea. The rate of in-hospital mortality was 1.3%. Conclusions: The PD with SMA first approach combined TMpE for periampullary malignancies was effective in achieving superior oncological statistics (rate of MP R0-resection and number of total resected LNs) with non-inferior short-term outcomes. It is necessary to evaluate survival outcomes with long-term follow-up.

2.
Molecules ; 28(8)2023 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-37110831

RESUMEN

Multi-target drug development has become an attractive strategy in the discovery of drugs to treat of Alzheimer's disease (AzD). In this study, for the first time, a rule-based machine learning (ML) approach with classification trees (CT) was applied for the rational design of novel dual-target acetylcholinesterase (AChE) and ß-site amyloid-protein precursor cleaving enzyme 1 (BACE1) inhibitors. Updated data from 3524 compounds with AChE and BACE1 measurements were curated from the ChEMBL database. The best global accuracies of training/external validation for AChE and BACE1 were 0.85/0.80 and 0.83/0.81, respectively. The rules were then applied to screen dual inhibitors from the original databases. Based on the best rules obtained from each classification tree, a set of potential AChE and BACE1 inhibitors were identified, and active fragments were extracted using Murcko-type decomposition analysis. More than 250 novel inhibitors were designed in silico based on active fragments and predicted AChE and BACE1 inhibitory activity using consensus QSAR models and docking validations. The rule-based and ML approach applied in this study may be useful for the in silico design and screening of new AChE and BACE1 dual inhibitors against AzD.


Asunto(s)
Acetilcolinesterasa , Enfermedad de Alzheimer , Humanos , Acetilcolinesterasa/uso terapéutico , Enfermedad de Alzheimer/tratamiento farmacológico , Inhibidores de la Colinesterasa/farmacología , Inhibidores de la Colinesterasa/uso terapéutico , Inhibidores de la Colinesterasa/química , Simulación del Acoplamiento Molecular , Secretasas de la Proteína Precursora del Amiloide , Ácido Aspártico Endopeptidasas , Precursor de Proteína beta-Amiloide
3.
J Biotechnol ; 366: 46-53, 2023 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-36933867

RESUMEN

Traditionally produced fish sauce can contain significant amounts of histamine. In some instances, the histamine concentration may be well above the limit recommended by the Codex Alimentarius Commission. The aim of this study was to discover new bacterial strains capable of growing under the stressful environmental conditions of fish sauce fermentation and metabolizing histamine. In this study, 28 bacterial strains were isolated from Vietnamese fish sauce products based on their ability to grow at high salt concentrations (23% NaCl) and tested for their ability to degrade histamine. Strain TT8.5 showed the highest histamine-degradation (45.1 ± 0.2% of initially 5 mM histamine within 7 days) and was identified as Virgibacillus campisalis TT8.5. Its histamine-degrading activity was shown to be localized intracellularly and the enzyme is a putative histamine dehydrogenase. The strain exhibited optimal growth and histamine-degrading activity at 37°C, pH 7%, and 5% NaCl in halophilic archaea (HA) histamine broth. It also showed pronounced histamine-degrading activity in HA histamine broth when cultivated at temperatures of up to 40 °C as well as in the presence of up to 23% NaCl. After treatment with immobilized cells, 17.6-26.9% of the initial histamine in various fish sauce products were reduced within 24 h of incubation, while no significant changes in other parameters of fish sauce quality were observed after this treatment. Our results indicate that V. campisalis TT8.5 is of potential interest to be applied in histamine degradation of traditional fish sauce.


Asunto(s)
Histamina , Virgibacillus , Animales , Histamina/metabolismo , Cloruro de Sodio/farmacología , Virgibacillus/metabolismo , Peces/metabolismo , Fermentación , Archaea/metabolismo
4.
Emerg Infect Dis ; 29(4): 778-781, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36696624

RESUMEN

Mpox was diagnosed in 2 women returning to Vietnam from the United Arab Emirates. The monkeypox viruses belonged to an emerging sublineage, A.2.1, distinct from B.1, which is responsible for the ongoing multicountry outbreak. Women could contribute to mpox transmission, and enhanced genomic surveillance is needed to clarify pathogen evolution.


Asunto(s)
Monkeypox virus , Mpox , Humanos , Femenino , Mpox/diagnóstico , Mpox/epidemiología , Emiratos Árabes Unidos/epidemiología , Vietnam/epidemiología
5.
Front Oncol ; 12: 888927, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36091142

RESUMEN

Introduction: Invasive Candida infection, or candidiasis, especially in gastrointestinal tract (GIT) is an infrequent but aggressive disease caused by Candida species. Candidiasis of gastrojejunostomosis after extensive gastrointestinal surgery may cause serious complications such as perforative peritonitis and anastomotic stenosis, which requires surgical interventions. Case presentation: Our two patients had undergone pancreaticoduodenectomy (PD), respectively, due to pancreatic ductal adenocarcinoma and intraductal papillary mucinous neoplasms of the pancreatic head. Both the patients were malnutritioned and debilitated before the surgery, and they required reoperation for postoperative Candidiasis-relevant complication.In the first case, the patient was readmitted to the hospital with symptoms of perforative peritonitis, for which he underwent surgery and had Candida found in both gastrojejunostomosis ulcer and peritoneal fluid. In our second case, the patient was admitted to the hospital twice after the first operation and diagnosed with Candida-induced gastrojejunostomosis stenosis by esophagogastroduodenoscopy (EGD) and endoscopic biopsy. Fluconazole was indicated for a 2-week regimen. Blood sample withdrawn afterward showed no evidence of fungal agents, and the anastomotic stenosis responded well to treatment. However, after 3 weeks, he came back with cachexia and symptoms of gastrojejunostomotic stenosis. EGD showed no image of fungal agents but anastomotic stenosis due to chronic inflammatory process. The patient was then reoperated to redo his gastrojejunostomosis. Conclusion: Candidiasis of gastrojejunostomosis after extensive gastrointestinal surgery such as PD is a very aggressive condition that may cause perforative peritonitis and anastomotic stenosis. However, there have been no publications on this disorder, and the strategic treatment remains unknown. We hereby present a report of two cases with postoperative gastrojejunostomosis candidiasis presenting with non-specific but aggressive and early clinical symptoms.

6.
Environ Dev Sustain ; : 1-46, 2022 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-35966336

RESUMEN

We are the first to empirically analyze the nexus of digital transformation and energy security (ES). This paper utilizes six indicators to reflect three aspects of ES, including acceptability, develop-ability, and sustainability. Applying the panel-corrected standard errors (PCSEs) and the feasible generalized least square estimates (FGLS) model to the international sample of 27 European countries over 2015 to 2019, this research reveals exciting findings. First, a promotion in digital transformation causes a significantly positive effect on the acceptability and sustainability of ES but a negative impact on develop-ability of ES. Second, the ES positively affects the digital transformation, especially the digital transformation in the business and public sectors. Third, results obtained from the dynamic fixed effects (DFEs) estimator for the autoregressive distributed lag (ARDL) method suggest that setting ES goals toward reducing energy consumption and pollution emission promotes the digital transformation process in the business sector of countries in the short run, while the promotion of renewable energy consumption helps countries enhance the digitalization process in the long run. Notably, digitalization is beneficial for sustainable economic development, reflected by a rise in non-fossil and renewable energy consumption and a diminish in CO2 emission, especially in the long run. Fourth, there is a nonlinear effect of the online transaction and digital public services on the acceptability, develop-ability, and sustainability of ES. In a similar spirit, the digital transformation is also accelerated more quickly if the efficiency of the energy system reaches a certain point.

7.
Clin Cancer Res ; 28(3): 540-551, 2022 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-34785581

RESUMEN

PURPOSE: Combined hepatocellular-cholangiocarcinoma (cHCC-CCA) is a rare malignancy associated with an overall poor prognosis. We aimed to investigate the immune profile of cHCC-CCA and determine its impact on disease outcome. EXPERIMENTAL DESIGN: We performed a multicenter study of 96 patients with cHCC-CCA. Gene expression profile was analyzed using nCounter PanCancer IO 360 Panel. Densities of main immune cells subsets were quantified from digital slides of IHC stainings. Genetic alterations were investigated using targeted next-generation sequencing. RESULTS: Two main immune subtypes of cHCC-CCA were identified by clustering analysis: an "immune-high" (IH) subtype (57% of the cases) and an "immune-low" (IL) subtype (43% of the cases). Tumors classified as IH showed overexpression of genes related to immune cells recruitment, adaptive and innate immunity, antigen presentation, cytotoxicity, immune suppression, and inflammation (P < 0.0001). IH cHCC-CCAs also displayed activation of gene signatures recently shown to be associated with response to immunotherapy in patients with HCC. Quantification of immunostainings confirmed that IH tumors were also characterized by higher densities of immune cells. Immune subtypes were not associated with any genetic alterations. Finally, multivariate analysis showed that the IH subtype was an independent predictor of improved overall survival. CONCLUSIONS: We have identified a subgroup of cHCC-CCA that displays features of an ongoing intratumor immune response, along with an activation of gene signatures predictive of response to immunotherapy in HCC. This tumor subclass is associated with an improved clinical outcome. These findings suggest that a subset of patients with cHCC-CCA may benefit from immunomodulating therapeutic approaches.


Asunto(s)
Neoplasias de los Conductos Biliares/inmunología , Neoplasias de los Conductos Biliares/terapia , Carcinoma Hepatocelular/inmunología , Carcinoma Hepatocelular/terapia , Colangiocarcinoma/inmunología , Colangiocarcinoma/terapia , Inmunoterapia , Neoplasias Hepáticas/inmunología , Neoplasias Hepáticas/terapia , Neoplasias Primarias Múltiples/inmunología , Neoplasias Primarias Múltiples/terapia , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de los Conductos Biliares/diagnóstico , Neoplasias de los Conductos Biliares/genética , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/genética , Colangiocarcinoma/diagnóstico , Colangiocarcinoma/genética , Femenino , Predicción , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/genética , Masculino , Persona de Mediana Edad , Neoplasias Primarias Múltiples/diagnóstico , Neoplasias Primarias Múltiples/genética , Resultado del Tratamiento
8.
Open Forum Infect Dis ; 6(7)2019 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-31363772

RESUMEN

BACKGROUND: Hand, foot, and mouth disease (HFMD) has become a major public health concern in the Asia-Pacific region. Knowledge of its economic burden is essential for policy makers in prioritizing the development and implementation of interventions. METHODS: A multi-hospital-based study was prospectively conducted at 3 major hospitals in Ho Chi Minh City, Vietnam, during 2016-2017. Data on direct and productivity costs were collected alongside clinical information and samples and demographic information from study participants. RESULTS: A total of 466 patients were enrolled. Two hundred three of 466 (43.6%) patients lived in Ho Chi Minh City, and 72/466 (15.5%) had severe HFMD. An enterovirus was identified in 74% of 466 patients, with EV-A71, CV-A6, CV-A10, and CV-A16 being the most common viruses identified (236/466, 50.6%). The mean economic burden per case was estimated at US$400.80 (95% confidence interval [CI], $353.80-$448.90), of which the total direct (medical) costs accounted for 69.7%. There were considerable differences in direct medical costs between groups of patients with different clinical severities and pathogens (ie, EV-A71 vs non-EV-A71). In Vietnam, during 2016-2017, the economic burden posed by HFMD was US$90 761 749 (95% CI, $79 033 973-$103 009 756). CONCLUSIONS: Our findings are of public health significance because for the first time we demonstrate that HFMD causes a substantial economic burden in Vietnam, and although multivalent vaccines are required to control HFMD, effective EV-A71 vaccine could substantially reduce the burden posed by severe HFMD. The results will be helpful for health policy makers in prioritizing resources for the development and implementation of intervention strategies to reduce the burden of HFMD.

9.
PLoS One ; 14(3): e0212734, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30865664

RESUMEN

BACKGROUND: The highest burden of disease from hepatitis C virus (HCV) is found in Southeast Asia, but our understanding of the epidemiology of infection in many heavily burdened countries is still limited. In particular, there is relatively little data on acute HCV infection, the outcome of which can be influenced by both viral and host genetics which differ within the region. We studied HCV genotype and IL28B gene polymorphism in a cohort of acute HCV-infected patients in Southern Vietnam alongside two other cohorts of chronic HCV-infected patients to better understand the epidemiology of HCV infection locally and inform the development of programs for therapy with the increasing availability of directly acting antiviral therapy (DAAs). METHODS: We analysed plasma samples from patients with acute and chronic HCV infection, including chronic HCV mono-infection and chronic Human Immunodeficiency Virus (HIV)-HCV coinfection, who enrolled in four epidemiological or clinical research studies. HCV infection was confirmed with RNA testing. The 5' UTR, core and NSB5 regions of HCV RNA positive samples were sequenced, and the genotype and subtype of the viral strains were determined. Host DNA from all HCV positive patients and age- and sex-matched non-HCV-infected control individuals were analysed for IL28B single nucleotide polymorphism (SNP) (rs12979860 and rs8099917). Geolocation of the patients were mapped using QGIS. RESULTS: 355 HCV antibody positive patients were analysed; 54.6% (194/355) and 46.4% (161/355) were acute and chronic infections, respectively. 50.4% (81/161) and 49.6.4% (80/161) of chronic infections had HCV mono-infection and HIV-HCV coinfection, respectively. 88.7% (315/355) and 10.1% (36/355) of the patients were from southern and central regions of Vietnam, respectively. 92.4% (328/355) of patients were HCV RNA positive, including 86.1% (167/194) acute and 100% (161/161) chronic infections. Genotype could be determined in 98.4% (322/328) patients. Genotypes 1 (56.5%; 182/322) and 6 (33.9%; 109/322) predominated. Genotype 1 including genotype 1a was significantly higher in HIV-HCV coinfected patients compared to acute HCV patients [43.8% (35/80) versus 20.5% (33/167)], (p = <0.001), while genotype 6 was significantly higher in chronic HCV mono-infected patients [(44.4% (36/81) versus 20.0% (16/80)] (p = < 0.004) compared to HIV-HCV coinfected patients. The prevalence of IL28B SNP (rs12979860) homozygous CC was 86.46% (83/96) in control individuals and was significantly higher in acutely-infected compared to chronically-infected patients [93.2 (82/88) versus 76.1% (35/46)] (p = < 0.005). CONCLUSION: HCV genotype 6 is highly prevalent in Vietnam and the high prevalence in treatment naïve chronic HCV patients may results from poor spontaneous clearance of acute HCV infection with genotype 6.


Asunto(s)
Coinfección , Genotipo , Infecciones por VIH , VIH-1/genética , Hepacivirus/genética , Hepatitis C Crónica , ARN Viral/genética , Enfermedad Aguda , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Coinfección/epidemiología , Coinfección/genética , Femenino , Infecciones por VIH/epidemiología , Infecciones por VIH/genética , Hepatitis C Crónica/epidemiología , Hepatitis C Crónica/genética , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Prevalencia , Vietnam/epidemiología
10.
Basic Res Cardiol ; 114(2): 8, 2019 01 14.
Artículo en Inglés | MEDLINE | ID: mdl-30643968

RESUMEN

Mice with a global deletion of α1AMPK are characterized by endothelial dysfunction and NADPH oxidase subunit 2 (NOX-2)-mediated vascular oxidative stress. However, the underlying mechanisms are incompletely understood and may involve endothelial NOX-2 upregulation or facilitated vascular infiltration of phagocytic cells. Therefore, the current study was designed to investigate the vascular effects of chronic angiotensin II (AngII) infusion in mice with an endothelial-specific α1AMPK deletion. A mouse strain with endothelial-specific α1AMPK deletion was generated by breeding α1AMPKflox/flox mice with TekCre+ or Cadh5Cre+ mice. Chronic AngII infusion (0.5 mg/kg/day for 7day) caused mild endothelial dysfunction in wild-type mice that was significantly aggravated in endothelial α1AMPK knockout mice. Aortic NOX-2 and CD68 expression were increased, indicating that infiltrating leukocytes may significantly contribute to enhanced vascular oxidative stress. Flow cytometry revealed a higher abundance of aortic CD90.2+ T-cells, CD11b+F4/80+ macrophages and Ly6G-Ly6C+ monocytes. Vascular mRNA expression of monocyte chemoattractant protein 1, CCL5 and vascular cell adhesion molecule 1 was enhanced in AngII-infused mice lacking endothelial α1AMPK, facilitating the recruitment of inflammatory cells to the vessel wall. In addition, AngII-induced upregulation of cytoprotective heme oxygenase 1 (HO-1) was blunted in mice with endothelial α1AMPK deletion, compatible with an impaired antioxidant defense in these animals. In summary, endothelial expressed α1AMPK limits the recruitment of inflammatory cells to the vessel wall and maintains HO-1 mediated antioxidant defense. Both mechanisms reduce vascular oxidative damage and preserve endothelial function during chronic AngII treatment.


Asunto(s)
Proteínas Quinasas Activadas por AMP/metabolismo , Endotelio Vascular/metabolismo , Angiotensina II/toxicidad , Animales , Antioxidantes/metabolismo , Endotelio Vascular/efectos de los fármacos , Hemo-Oxigenasa 1/metabolismo , Inflamación/metabolismo , Masculino , Proteínas de la Membrana/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Estrés Oxidativo/efectos de los fármacos , Estrés Oxidativo/fisiología
11.
Emerg Infect Dis ; 24(4): 654-662, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29553326

RESUMEN

Hand, foot and mouth disease (HFMD) is a major public health issue in Asia and has global pandemic potential. Coxsackievirus A6 (CV-A6) was detected in 514/2,230 (23%) of HFMD patients admitted to 3 major hospitals in southern Vietnam during 2011-2015. Of these patients, 93 (18%) had severe HFMD. Phylogenetic analysis of 98 genome sequences revealed they belonged to cluster A and had been circulating in Vietnam for 2 years before emergence. CV-A6 movement among localities within Vietnam occurred frequently, whereas viral movement across international borders appeared rare. Skyline plots identified fluctuations in the relative genetic diversity of CV-A6 corresponding to large CV-A6-associated HFMD outbreaks worldwide. These data show that CV-A6 is an emerging pathogen and emphasize the necessity of active surveillance and understanding the mechanisms that shape the pathogen evolution and emergence, which is essential for development and implementation of intervention strategies.


Asunto(s)
Enfermedades Transmisibles Emergentes/epidemiología , Enfermedades Transmisibles Emergentes/virología , Infecciones por Coxsackievirus/epidemiología , Infecciones por Coxsackievirus/virología , Enterovirus Humano A , Enfermedad de Boca, Mano y Pie/epidemiología , Enfermedad de Boca, Mano y Pie/virología , Adolescente , Adulto , Niño , Enterovirus Humano A/clasificación , Enterovirus Humano A/genética , Enterovirus Humano A/aislamiento & purificación , Femenino , Genoma Viral , Genómica/métodos , Humanos , Masculino , Filogenia , Filogeografía , Vietnam/epidemiología , Secuenciación Completa del Genoma , Adulto Joven
12.
Bioorg Chem ; 71: 160-169, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28196602

RESUMEN

In our search for novel small molecules targeting histone deacetylases, we have designed and synthesized two series of novel N-hydroxybenzamides incorporating 2-oxoindolines (4a-g, 6a-g). Biological evaluation showed that these benzamides potently inhibited HDAC2 with IC50 values in sub-micromolar range. In three human cancer cell lines the synthesized compounds were up to 4-fold more cytotoxic than SAHA. Docking experiments indicated that the compounds tightly bound to HDAC2 at the active binding site with binding affinities much higher than that of SAHA. Our present results demonstrate that these novel and simple N-hydroxybenzamides are potential for further development as anticancer agents and further investigation of similarly simple N-hydroxybenzamides should be warranted to obtain more potent HDAC inhibitors.


Asunto(s)
Antineoplásicos/química , Antineoplásicos/farmacología , Histona Desacetilasa 2/antagonistas & inhibidores , Inhibidores de Histona Desacetilasas/química , Inhibidores de Histona Desacetilasas/farmacología , Indoles/química , Indoles/farmacología , Antineoplásicos/síntesis química , Benzamidas/síntesis química , Benzamidas/química , Benzamidas/farmacología , Línea Celular Tumoral , Química Clic , Cristalografía por Rayos X , Ensayos de Selección de Medicamentos Antitumorales , Histona Desacetilasa 2/metabolismo , Inhibidores de Histona Desacetilasas/síntesis química , Histona Desacetilasas/metabolismo , Humanos , Ácidos Hidroxámicos/síntesis química , Ácidos Hidroxámicos/química , Ácidos Hidroxámicos/farmacología , Indoles/síntesis química , Simulación del Acoplamiento Molecular , Neoplasias/tratamiento farmacológico , Neoplasias/enzimología , Relación Estructura-Actividad
13.
Med Chem ; 11(3): 296-304, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25256241

RESUMEN

The search for newer histone deacetylase (HDAC) inhibitors has attracted a great deal of interest of medicinal chemists worldwide, especially after the first HDAC inhibitor (Zolinza(®), widely known as SAHA or Suberoylanilide hydroxamic acid) was approved by the FDA for the treatment of Tcell lymphoma in 2006. As a continuity of our ongoing research in this area, we designed and synthesized a series of 5-aryl-1,3,4-thiadiazole-based hydroxamic acids as analogues of SAHA and evaluated their biological activities. Most of the compounds in this series, e.g. compounds with 5-aryl moiety being 2- furfuryl (5a), 5-bromofuran-2-yl (5b), 5-methylfuran-2-yl (5c), thiophen-2-yl (5d), 5-methylthiophen-2-yl (5f) and pyridyl (5g-i), were found to have potent anticancer cytotoxicity with IC50 values of generally 5- to 10-fold lower than that of SAHA in 4 human cancer cell lines assayed. Those compounds with potent cytotoxicity were also found to have strong HDAC inhibition effects. Docking studies revealed that compounds 5a and 5d displayed high affinities towards HDAC2 and 8.


Asunto(s)
Antineoplásicos/farmacología , Inhibidores de Histona Desacetilasas/farmacología , Histona Desacetilasas/metabolismo , Ácidos Hidroxámicos/farmacología , Simulación del Acoplamiento Molecular , Tiadiazoles/química , Antineoplásicos/síntesis química , Antineoplásicos/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Inhibidores de Histona Desacetilasas/síntesis química , Inhibidores de Histona Desacetilasas/química , Humanos , Ácidos Hidroxámicos/síntesis química , Ácidos Hidroxámicos/química , Células MCF-7 , Estructura Molecular , Relación Estructura-Actividad
14.
Diagn Microbiol Infect Dis ; 79(4): 463-7, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24923210

RESUMEN

Treatment options for multidrug-resistant pathogens remain problematic in many regions and individual countries, warranting ongoing surveillance and analysis. Limited antimicrobial susceptibility information is available for pathogens from Vietnam. This study determined the bacterial susceptibility of aerobic gram-negative pathogens of intra-abdominal infections among patients in Vietnam during 2009-2011. A total of 905 isolates were collected from 4 medical centers in this investigation as part of the Study for Monitoring Antimicrobial Resistance Trends. Antimicrobial susceptibility and extended-spectrum beta-lactamase (ESBL) rates among the appropriate species were determined by a central laboratory using Clinical and Laboratory Standards Institute methods. Among the species collected, Escherichia coli (48.1% ESBL-positive) and Klebsiella pneumoniae (39.5% ESBL-positive) represented the majority (46.4%) of the isolates submitted for this study. Ertapenem MIC90 values were lowest for these 2 species at 0.12 and 0.25µg/mL and remained unchanged for ESBL-positive isolates. Imipenem MIC90 values were also the same for all isolates and ESBL-positive strains at 0.25 and 0.5µg/mL, respectively. Ertapenem MIC90 values for additional species with sufficient numbers for analysis, including Enterobacter cloacae, Proteus mirabilis, Acinetobacter baumannii, and Pseudomonas aeruginosa, were 1, 0.06, >4, and >4µg/mL, respectively. Analysis of beta-lactamases in a subset of 132 phenotypically ESBL-positive Enterobacteriaceae demonstrated that CTX-M variants, particularly CTX-M-27 and CTX-M-15, were the predominant enzymes. High resistance rates in Vietnam hospitals dictate continuous monitoring as antimicrobial inactivating enzymes continue to spread throughout Asia and globally.


Asunto(s)
Farmacorresistencia Bacteriana , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Gramnegativas/genética , Infecciones por Bacterias Gramnegativas/epidemiología , Infecciones por Bacterias Gramnegativas/microbiología , Infecciones Intraabdominales/epidemiología , Infecciones Intraabdominales/microbiología , beta-Lactamasas/genética , Antibacterianos/farmacología , Carbapenémicos/farmacología , Infección Hospitalaria , Ertapenem , Bacterias Gramnegativas/clasificación , Bacterias Gramnegativas/aislamiento & purificación , Humanos , Pruebas de Sensibilidad Microbiana , Vietnam/epidemiología , beta-Lactamas/farmacología
16.
Nat Prod Commun ; 4(3): 323-5, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19413107

RESUMEN

From the methanolic extract of the roots of Clerodendrum philipinum, a new rearranged abietane diterpene (1) and eight known compounds were isolated by various chromatography methods. Their structures were identified by means of spectroscopic methods, including 1D- and 2D-NMR, as 17(15-->16),18(4-->3)-bisabeo-11,12,14,16-tetrahydroxy-3,5,8,11,13,15-abietahexaen-7-one (1), binankadsurin A, clerodenoside A, martynoside, acteoside, isoacteoside, astragalin, p3-sitosterol, and daucosterol. Binankadsurin A was found for the first time from a Clerodendrum species.


Asunto(s)
Abietanos/análisis , Abietanos/aislamiento & purificación , Clerodendrum/química , Lignanos/análisis , Lignanos/aislamiento & purificación , Cromatografía , Glucósidos/aislamiento & purificación , Quempferoles/aislamiento & purificación , Espectroscopía de Resonancia Magnética , Metanol , Estructura Molecular , Fenoles/aislamiento & purificación , Sitoesteroles/aislamiento & purificación
17.
J Virol ; 83(13): 6363-74, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19386701

RESUMEN

The respiratory syncytial virus (RSV) M2-1 protein is an essential cofactor of the viral RNA polymerase complex and functions as a transcriptional processivity and antitermination factor. M2-1, which exists in a phosphorylated or unphosphorylated form in infected cells, is an RNA-binding protein that also interacts with some of the other components of the viral polymerase complex. It contains a CCCH motif, a putative zinc-binding domain that is essential for M2-1 function, at the N terminus. To gain insight into its structural organization, M2-1 was produced as a recombinant protein in Escherichia coli and purified to >95% homogeneity by using a glutathione S-transferase (GST) tag. The GST-M2-1 fusion proteins were copurified with bacterial RNA, which could be eliminated by a high-salt wash. Circular dichroism analysis showed that M2-1 is largely alpha-helical. Chemical cross-linking, dynamic light scattering, sedimentation velocity, and electron microscopy analyses led to the conclusion that M2-1 forms a 5.4S tetramer of 89 kDa and approximately 7.6 nm in diameter at micromolar concentrations. By using a series of deletion mutants, the oligomerization domain of M2-1 was mapped to a putative alpha-helix consisting of amino acid residues 32 to 63. When tested in an RSV minigenome replicon system using a luciferase gene as a reporter, an M2-1 deletion mutant lacking this region showed a significant reduction in RNA transcription compared to wild-type M2-1, indicating that M2-1 oligomerization is essential for the activity of the protein. We also show that the region encompassing amino acid residues 59 to 178 binds to P and RNA in a competitive manner that is independent of the phosphorylation status of M2-1.


Asunto(s)
ARN Viral/metabolismo , Virus Sincitial Respiratorio Humano/química , Proteínas Virales/química , Proteínas Estructurales Virales/metabolismo , Sitios de Unión , Dicroismo Circular , Fosforilación , Dominios y Motivos de Interacción de Proteínas , Mapeo de Interacción de Proteínas , Estructura Cuaternaria de Proteína , Estructura Secundaria de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Virus Sincitial Respiratorio Humano/genética , Proteínas Virales/genética , Proteínas Virales/aislamiento & purificación
18.
J Gen Virol ; 88(Pt 1): 196-206, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17170452

RESUMEN

The respiratory syncytial virus (RSV) phosphoprotein (P) is a major polymerase co-factor that interacts with both the large polymerase fragment (L) and the nucleoprotein (N). The N-binding domain of RSV P has been investigated by co-expression of RSV P and N proteins in Escherichia coli. Pull-down assays performed with a series of truncated forms of P fused to glutathione S-transferase (GST) revealed that the region comprising the last nine C-terminal amino acid residues of P (233-DNDLSLEDF-241) is sufficient for efficient binding to N. Site-directed mutagenesis shows that the last four residues of this peptide are crucial for binding and must be present at the end of a flexible C-terminal tail. The presence of the P oligomerization domain (residues 100-160) was an important stabilizing factor for the interaction. The tetrameric full-length P fused to GST was able to pull down both helical and ring structures, whereas a monomeric C-terminal fragment of P (residues 161-241) fused to GST pulled down exclusively RNA-N rings. Electron-microscopy analysis of the purified rings showed the presence of two types of complex: undecamers (11N) and decamers (10N). Mass-spectrometry analysis of the RNA extracted from rings after RNase A treatment showed two peaks of 22,900 and 24,820 Da, corresponding to a mean RNA length of 67 and 73 bases, respectively. These results suggest strongly that each N subunit contacts 6 nt, with an extra three or four bases further protected from nuclease digestion by the ring structure at both the 5' and 3' ends.


Asunto(s)
Fosfoproteínas/metabolismo , Regiones Promotoras Genéticas/fisiología , Virus Sincitiales Respiratorios/química , Ribonucleoproteínas/química , Sustitución de Aminoácidos , Espectrometría de Masas , Fragmentos de Péptidos/química , Fragmentos de Péptidos/metabolismo , Fosfoproteínas/química , ARN Bacteriano/análisis , Proteínas Recombinantes de Fusión/biosíntesis , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/metabolismo , Ribonucleoproteínas/metabolismo
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