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1.
J Invertebr Pathol ; 205: 108142, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38788921

RESUMO

This study aims to investigate the use of pond apple (Annona glabra) compounds as a novel strategy to prevent and treat acute hepatopancreatic necrosis disease (AHPND) as well as to better understand the mechanism of health improvement in shrimp. The A. glabra leaf extracts were extracted using various solvents and examined for in vitro and in vivo activity against Vibrio parahaemolyticus strains. In comparison with ethanol and water extracts, methanol extract showed the strongest bactericidal effect (MBC/MIC ratio of 2.50 ± 1.00), with minimal inhibitory concentration (MIC) of 0.023 ± 0.012 mg ml-1 and minimum bactericidal concentration (MBC) of 0.065 ± 0.062 mg ml-1. White leg shrimp (P. vannamei, body weight 10.37 ± 0.27 g) fed A. glabra methanol extracts-containing diets (AMEDs) at 1 %, 1.5 %, and 2.0 % demonstrated no deleterious effects on survival and were significantly increased in length and weight after 30 days of feeding. The level of total haemocyte, hyaline haemocyte on day 15 and granulocyte on day 30 remarkably increased (p < 0.05) in shrimps fed AMEDs groups compared to those in the control group. The finding demonstrates that granulocyte was induced time dependently. In particular, the survival rate of V. parahaemolyticus challenged shrimps under medication with AMEDs at 1.5 % and 2.0 % was significantly higher (p < 0.05) than that of the control group. The decrease in bacterial load of Vibrio spp. and V. parahaemolyticus was obviously recorded in hepatopancreas shrimp given AMEDs 1.5 % and 2.0 % and may be linked to herb characteristics such as antibacterial activity, enhancing innate immunity, and its potential to maintain the integrity of hepatopancreatic tissue. Our findings suggest that A. glabra extract might be used as a health enhancer in commercial farmed shrimp.


Assuntos
Annona , Hepatopâncreas , Penaeidae , Extratos Vegetais , Vibrio parahaemolyticus , Animais , Penaeidae/microbiologia , Penaeidae/efeitos dos fármacos , Extratos Vegetais/farmacologia , Vibrio parahaemolyticus/efeitos dos fármacos , Annona/química , Hepatopâncreas/efeitos dos fármacos , Hepatopâncreas/patologia , Antibacterianos/farmacologia
2.
Int J Psychiatry Med ; 58(2): 86-101, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36437044

RESUMO

OBJECTIVE: This research was conducted to identify the prevalence and associated factors of depressive disorders, as well as evaluate the recognition rate of general practitioners in detecting these mental health issues in primary care. METHOD: Five hundred and twelve participants (55.3% female, mean age = 46.35 years) were assessed by psychiatrists based on the DSM-5 clinical procedures over a two-month survey in a primary care facility in Ho Chi Minh City, Vietnam. RESULTS: There were 15.8% (95% confidence interval [CI] 12.9-19.2) of the population having depressive disorders, with major depressive disorder being the most prevalent subtype at 8% (95% CI 5.9-10.6). General practitioners could detect depressive disorders in 2.5% of all cases (95% CI .5-7.7). Significantly linked with depressive disorders in multivariable analysis were Chinese ethnic or other minority races (adjusted odds ratios [aOR] = 4.10, 95% CI 1.04-16.12), and low economic status (aOR = 5.41, 95% CI 1.29-22.59). CONCLUSIONS: The high prevalence of depressive disorders in outpatients of primary care clinics may raise the awareness of the practitioners about screening and other appropriate actions to tackle the issue.


Assuntos
Transtorno Depressivo Maior , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Transtorno Depressivo Maior/diagnóstico , Transtorno Depressivo Maior/epidemiologia , Vietnã/epidemiologia , Estudos Transversais , Prevalência , Atenção Primária à Saúde
3.
Molecules ; 28(13)2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37446780

RESUMO

Removing antibiotics from water is critical to prevent the emergence and spread of antibiotic resistance, protect ecosystems, and maintain the effectiveness of these vital medications. The combination of ozone and electrocoagulation in wastewater treatment provides enhanced removal of contaminants, improved disinfection efficiency, and increased overall treatment effectiveness. In this work, the removal of sulfamethoxazole (SMX) from an aqueous solution using an ozone-electrocoagulation (O-EC) system was optimized and modeled. The experiments were designed according to the central composite design. The parameters, including current density, reaction time, pH, and ozone dose affecting the SMX removal efficiency of the OEC system, were optimized using a response surface methodology. The results show that the removal process was accurately predicted by the quadric model. The numerical optimization results show that the optimum conditions were a current density of 33.2 A/m2, a time of 37.8 min, pH of 8.4, and an ozone dose of 0.7 g/h. Under these conditions, the removal efficiency reached 99.65%. A three-layer artificial neural network (ANN) with logsig-purelin transfer functions was used to model the removal process. The data predicted by the ANN model matched well to the experimental data. The calculation of the relative importance showed that pH was the most influential factor, followed by current density, ozone dose, and time. The kinetics of the SMX removal process followed the first-order kinetic model with a rate constant of 0.12 (min-1). The removal mechanism involves various processes such as oxidation and reduction on the surface of electrodes, the reaction between ozone and ferrous ions, degradation of SMX molecules, formation of flocs, and adsorption of species on the flocs. The results obtained in this work indicate that the O-EC system is a potential approach for the removal of antibiotics from water.


Assuntos
Ozônio , Poluentes Químicos da Água , Sulfametoxazol/química , Ozônio/química , Ecossistema , Poluentes Químicos da Água/química , Antibacterianos , Eletrocoagulação , Redes Neurais de Computação , Água
4.
Chemistry ; 28(3): e202103437, 2022 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-34731507

RESUMO

The precise detection of the toxic gas H2 S requires reliable sensitivity and specificity of sensors even at minute concentrations of as low as 10 ppm, the value corresponding to typical exposure limits. CuO can be used for H2 S dosimetry, based on the formation of conductive CuS and the concomitant significant increase in conductance. In theory, at elevated temperature the reaction is reversed and CuO is formed, ideally enabling repeated and long-term use of one sensor. Yet, the performance of CuO tends to drop upon cycling. Utilizing defined CuO nanorods we thoroughly elucidated the associated detrimental chemical changes directly on the sensors, by Raman and electron microscopy analysis of each step during sensing (CuO→CuS) and regeneration (CuS→CuO) cycles. We find the decrease in the sensing performance is mainly caused by the irreversible formation of CuSO4 during regeneration. The findings allowed us to develop strategies to reduce CuSO4 formation and thus to substantially maintain the sensing stability even for repeated cycles. We achieved CuO-based dosimeters possessing a response time of a few minutes only, even for 10 ppm H2 S, and prolonged life-time.


Assuntos
Cobre , Nanotubos
5.
Conserv Biol ; 36(3): e13873, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34865262

RESUMO

Tree diversity in Asia's tropical and subtropical forests is central to nature-based solutions. Species vulnerability to multiple threats, which affect provision of ecosystem services, is poorly understood. We conducted a region-wide, spatially explicit assessment of the vulnerability of 63 socioeconomically important tree species to overexploitation, fire, overgrazing, habitat conversion, and climate change. Trees were selected for assessment from national priority lists, and selections were validated by an expert network representing 20 countries. We used Maxent suitability modeling to predict species distribution ranges, freely accessible spatial data sets to map threat exposures, and functional traits to estimate threat sensitivities. Species-specific vulnerability maps were created as the product of exposure maps and sensitivity estimates. Based on vulnerability to current threats and climate change, we identified priority areas for conservation and restoration. Overall, 74% of the most important areas for conservation of these trees fell outside protected areas, and all species were severely threatened across an average of 47% of their native ranges. The most imminent threats were overexploitation and habitat conversion; populations were severely threatened by these factors in an average of 24% and 16% of their ranges, respectively. Our model predicted limited overall climate change impacts, although some study species were likely to lose over 15% of their habitat by 2050 due to climate change. We pinpointed specific natural areas in Borneo rain forests as hotspots for in situ conservation of forest genetic resources, more than 82% of which fell outside designated protected areas. We also identified degraded areas in Western Ghats, Indochina dry forests, and Sumatran rain forests as hotspots for restoration, where planting or assisted natural regeneration will help conserve these species, and croplands in southern India and Thailand as potentially important agroforestry options. Our results highlight the need for regionally coordinated action for effective conservation and restoration.


Especies de Árboles Valoradas y Amenazadas de Asia Tropical y Subtropical Resumen La diversidad de árboles en los bosques tropicales y subtropicales de Asia es un eje central para las soluciones basadas en la naturaleza. La vulnerabilidad de las especies ante las múltiples amenazas, las cuales afectan el suministro de servicios ambientales, es un tema poco comprendido. Realizamos una evaluación regional espacialmente explícita de la vulnerabilidad de 63 especies de árboles de importancia socioeconómica ante la sobreexplotación, incendios, sobrepastoreo, conversión del hábitat y cambio climático. Los árboles se seleccionaron para su evaluación a partir de listas nacionales de prioridades, y las selecciones fueron validadas por una red de expertos de 20 países. Usamos el modelado de idoneidad Maxent para predecir el rango de distribución de las especies, conjuntos de datos espaciales de libre acceso para mapear la exposición a las amenazas y rasgos funcionales para estimar la susceptibilidad a las amenazas. Con base en la vulnerabilidad a las amenazas actuales y al cambio climático, identificamos las áreas prioritarias para su conservación y restauración. En general, el 74% de las áreas más importantes para la conservación de estos árboles quedó fuera de las áreas protegidas y todas las especies estaban seriamente amenazadas en promedio en el 47% de su distribución nativa. Las amenazas más inminentes fueron la sobreexplotación y la conversión del hábitat; las poblaciones estuvieron seriamente amenazadas por estos factores en promedio en el 24% y 16% de su distribución, respectivamente. Nuestro modelo predijo un impacto general limitado del cambio climático, aunque algunas especies estudiadas tuvieron la probabilidad de perder más del 15% de su hábitat para el 2050 debido a este factor. Identificamos áreas naturales específicas en las selvas de Borneo como puntos calientes para la conservación in situ de los recursos genéticos forestales, más del 82% de los cuales estaban fuera de las áreas protegidas designadas. También identificamos áreas degradadas en los Ghats Occidentales, los bosques secos de Indochina y las selvas de Sumatra como puntos calientes para la restauración, en donde la siembra o la regeneración natural asistida ayudarán a conservar estas especies. Además, identificamos campos de cultivo al sur de India y Tailandia como potenciales opciones importantes de agrosilvicultura. Nuestros resultados resaltan la necesidad de acciones regionales coordinadas para la conservación y restauración efectivas.


Assuntos
Ecossistema , Árvores , Mudança Climática , Conservação dos Recursos Naturais , Florestas , Tailândia
6.
Phytopathology ; 112(7): 1524-1536, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35238604

RESUMO

Cassiicolin (Cas), a toxin produced by Corynespora cassiicola, is responsible for Corynespora leaf fall disease in susceptible rubber trees. Currently, the molecular mechanisms of the cytotoxicity of Cas and its host selectivity have not been fully elucidated. Here, we analyzed the binding of Cas1 and Cas2 to membranes consisting of different plant lipids and their membrane disruption activities. Using high-speed atomic force microscopy and confocal microscopy, we reveal that the binding and disruption activities of Cas1 and Cas2 on lipid membranes are strongly dependent on the specific plant lipids. The negative phospholipids, glycerolipids, and sterols are more sensitive to membrane damage caused by Cas1 and Cas2 than neutral phospholipids and betaine lipids. Mature Cas1 and Cas2 play an essential role in causing membrane disruption. Cytotoxicity tests on rubber leaves of Rubber Research Institute of Vietnam (RRIV) 1, RRIV 4, and Prang Besar (PB) 255 clones suggest that the toxins cause necrosis of rubber leaves, except for the strong resistance of PB 255 against Cas2. Cryogenic scanning electron microscopy analyses of necrotic leaf tissues treated with Cas1 confirm that cytoplasmic membranes are vulnerable to the toxin. Thus, the host selectivity of Cas toxin is attained by the lipid-dependent binding activity of Cas to the membrane, and the cytotoxicity of Cas arises from its ability to form biofilm-like structures and to disrupt specific membranes.


Assuntos
Proteínas Associadas a CRISPR , Hevea , Lipídeos , Doenças das Plantas , Folhas de Planta/metabolismo , Borracha
7.
Heart Vessels ; 37(8): 1326-1336, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35178606

RESUMO

We sought to examine the impact of gender differences in clinical outcomes at 3 years also comparing the role of double versus single stenting approach for the treatment of coronary unprotected LM bifurcation lesions. We retrospectively analyzed both the procedural and medical data of patients referred to our hub center for complex LM bifurcation disease, treated using Crossover provisional stenting, T or T-and-Protrusion (TAP), Culotte, and Nano-inverted-T (NIT) techniques between January 1st, 2008 and May 1st 2018. The main outcome of the study was to evaluate the association between gender and target lesion failure (TLF) based on the different stenting technique used. Five hundred and sixty-seven patients (251 females, mean age 70.0 ± 10 years, mean Syntax score 31.6 ± 6.3) were evaluated. Crossover, T or TAP, culotte and NIT techniques were performed in 171 (30.1%), 61 (10.7%), 98 (17.2%) and 237 (41.8%) patients, respectively with no differences in baseline and peri-procedural items among gender. At a mean follow-up of 37.1 ± 10.8 months (range 22.1-39.3 moths), the overall TLF rate, cardiovascular mortality and stent thrombosis were 12.1%, 3.1% and 1.0%, respectively. Female gender was associated with an increased rate of major bleeding when treated with double stent strategy (p = 0.02). No gender difference in TLF was noted among gender, independently from the stenting approach used. Among patients with ULM bifurcation disease undergoing PCI, TLF rates were not different between genders at 3-year follow-up either using a single or double stent technique.


Assuntos
Doença da Artéria Coronariana , Intervenção Coronária Percutânea , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/cirurgia , Feminino , Humanos , Masculino , Intervenção Coronária Percutânea/métodos , Estudos Retrospectivos , Fatores de Risco , Stents , Fatores de Tempo , Resultado do Tratamento
8.
Am J Otolaryngol ; 43(3): 103397, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35210111

RESUMO

PURPOSE: To evaluate the efficiency of a biodegradable gel containing hyaluronic acid and berberine hydrochloride in endoscopic sinus surgery. METHODS: Sixty-six chronic rhinosinusitis patients with or without nasal polyps who underwent bilateral endoscopic sinus surgery (ESS) were randomly received a biodegradable gel containing hyaluronic acid and berberine hydrochloride or merocel in both middle meatal spacers at the end procedure of ESS. Lund-Kennedy endoscopic score (LKES) was used to examine status of nasal cavity on preoperative day and postoperative day 1 to 7. The LKES ratio was calculated as the LKES on postoperative day divided into the LKES on preoperative day. Visual analogue score (VAS) was used to assess patient's status from the first postoperative day to the hospital discharge day. The average VAS during hospital stays was calculated by the sum of VAS in each examination day divided into the number of examined day. The LKES ratio, the average of VAS during hospital stays and length of hospitalized day of the patients were used as clinical outcome indices in early stage after surgery. A general linear model adjusted for confounding factors was used for data analysis. RESULTS: Adjusted mean of LKES ratio were lower in group used biodegrable gel of hyaruloic acid and berberin hydrochlode (study group) than those in merocele group in the postoperative day 1 to day 7. However, significant difference was found in the adjusted mean of LKES ratio on the postoperative day 2 to 6. Similarly, the adjusted mean of VAS during hospital stays and length of hospitalized day after surgery in study group were significantly decreased as compared with those in merocele group. CONCLUSIONS: Biodegradable material containing hyaluronic acid and berberine hydrochloride was more effective than merocel in length of hospital stay, post-operative symptoms, and sinus cavity's status in early stage after ESS.


Assuntos
Berberina , Pólipos Nasais , Rinite , Sinusite , Doença Crônica , Endoscopia/métodos , Humanos , Ácido Hialurônico , Pólipos Nasais/cirurgia , Estudos Prospectivos , Rinite/diagnóstico , Rinite/cirurgia , Sinusite/diagnóstico , Sinusite/cirurgia , Resultado do Tratamento
9.
Appl Microbiol Biotechnol ; 105(16-17): 6345-6354, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34410438

RESUMO

VP28 is an envelope protein of White Spot Syndrome Virus (WSSV), which has been shown in previous studies to induce a high immune response in shrimp. VP28 has been produced in some host systems such as Escherichia coli, Bacillus subtilis, and Pichia pastoris as free protein. Here we showed a new strategy of anchoring VP28 on the Saccharomyces cerevisiae yeast surface and using the yeast cell extract combined with probiotic as an oral vaccine for shrimp farming. We have successfully constructed a recombinant yeast cell capable of expressing VP28 on the cell surface. The feeding diet combined with VP28 anchored yeast cell extract provided significant assurance to Litopenaeus vannamei, challenged by WSSV, resulting in a relative percent survival (RPS) of 87.10 ± 2.15%. Interestingly, the utilization of VP28 anchored yeast cell extract could enhance the efficiency of probiotic strains like Lactobacillus and Bacillus on shrimp farming. The results in both laboratory scales and field trials using extract of VP28 displaying Saccharomyces showed a growth-promoting effect in shrimp, assessed through average shrimp weight. Taken together, our results in this study demonstrated a new successful strategy of using yeast cell surface as a tool to produce VP28-based oral vaccine for shrimp aquaculture. KEY POINTS: • A new strategy of using VP28 antigen as anchored protein on S. cerevisiae yeast cell surface (S. cerevisiae::VP28) • The utilization of VP28 antigen and yeast as S. cerevisiae::VP28 extract enhanced potential protection of Litopenaeus vannamei against White Spot Syndrome Virus (RPS 87.10%) • The use of S. cerevisiae::VP28 extract increased efficiency of probiotic on shrimp growth-promoting effect either lab-scale or field trial.


Assuntos
Penaeidae , Saccharomyces cerevisiae , Agricultura , Animais , Antígenos de Superfície , Saccharomyces cerevisiae/genética , Saccharomycetales , Proteínas do Envelope Viral
10.
Environ Monit Assess ; 193(12): 774, 2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34741217

RESUMO

This research explored the long-term relationships of climate parameters and coastal water quality nearby shrimp farms in two countries. In Thailand, two sampling points in canals located in Bangkok and Trang provinces were selected as the urban and tourism areas, respectively. In northern Vietnam, the canals located in Thai Binh and Quang Ninh provinces were used as the urban and tourism areas, respectively. The diurnal monitoring of water quality and weather was performed at each site to evaluate the relationships between climate and water quality, pollution load, and risk analysis. A questionnaire was also used to assess the climate and water exposure, vulnerability, and adaptability of each site. All data were ranked on a scale of 1 to 5 to integrate each factor. It was determined that the main water quality problem was fecal pollution. Notably, aquaculture farming in northern Vietnam is more vulnerable than in Thailand; however, Vietnam farmers were adaptable for climate variability.


Assuntos
Turismo , Qualidade da Água , Aquicultura , Monitoramento Ambiental , Tailândia , Vietnã
11.
Analyst ; 145(9): 3376-3384, 2020 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-32239000

RESUMO

A simple and fast method was developed for the determination of quercetin. The concentration of quercetin can be determined based on the fluorescence emission resulting from the coordinative interactions between quercetin and the yttrium ion (Y3+). Notably, a portable platform to quantitatively analyze quercetin was constructed. This platform incorporates our custom-built homemade reader based on a photodiode, and Arduino hardware, which accepts a paper ribbon on which Y3+ is deposited as an input. In addition, the color change of the paper ribbon was identified using a smartphone via the hue values of the photographs. The limits of detection for quercetin using spectroscopy, a smartphone, and a custom-built reader were calculated to be 27, 110, and 129 nM, respectively. The use of a custom-built device and a smartphone for detecting quercetin via fluorescence from the prepared paper ribbon reduces the time and cost of quercetin detection. This approach could be employed for on-site sensing of quercetin in real samples.

12.
Phys Chem Chem Phys ; 22(47): 27590-27599, 2020 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-33241818

RESUMO

KYF4 polycrystalline materials singly doped with Sm3+ ions and co-doped with Tb3+/Sm3+ ions were synthesized by the hydrothermal technique. The optical spectra of all samples were measured at room temperature. The features of the ligand field and the optical properties of Sm3+ ions in KYF4 were studied via Judd-Ofelt theory. A three-level model was used to estimate the validity of the Judd-Ofelt analysis for KYF4:Sm3+. The luminescence quenching of KYF4:Sm3+ relates to energy transfer through cross relaxation between Sm3+ ions. For KYF4:Tb3+,Sm3+, the luminescence of Sm3+ ions is enhanced due to the energy transfer process from Tb3+ to Sm3+. The chromaticity features of the luminescence from KYF4:Tb3+,Sm3+ were estimated by the chromaticity coordinates and correlated color temperature (CCT). The dominant interaction mechanism and the energy transfer parameters for the Sm3+-Sm3+ and Tb3+-Sm3+ energy transfer processes were analyzed by using the Inokuti-Hirayama model.

13.
Inorg Chem ; 57(18): 11696-11703, 2018 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-30160112

RESUMO

We report a novel example of supramolecular cages containing a Lewis acidic trigonal boron center. Self-assembly of the tris(pyridyl)borane donor 1 with diruthenium (2) or platinum (3), as an electron acceptor, furnished boron-containing trigonal prismatic supramolecular cages 5 and 6, which were characterized by 1H NMR and electrospray ionization time-of-flight mass spectroscopy and X-ray crystallography. The molecular structure of cage 5 was confirmed as a trigonal prismatic cage with an inner dimension of about 400 Å3. The fluoride binding properties of borane ligand 1 and Pt cage 6 were studied. UV/vis absorption titration studies demonstrated that the boron center of cage 6 undergoes strong binding interaction with the fluoride ion, with an estimated binding constant of 1.3 × 1010 M-2 in acetone based on the 1:2 binding isotherm. The binding was also confirmed by 1H NMR titration. Photoluminescence titration studies showed that cage 6 emitted borane-centered fluorescence (τ = 2.21 ns), which was gradually quenched upon addition of fluoride. When excess fluoride was added to a solution of 6, however, dissociation of the pyridyl ligand from the Pt(II) center was observed.

14.
Nanotechnology ; 29(20): 205501, 2018 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-29480163

RESUMO

Cuprous oxide (Cu2O) nanostructure has been synthesized using an electrochemical method with a two-electrode system. Cu foils were used as electrodes and NH2(OH) was utilized as the reducing agent. The effects of pH and applied voltages on the morphology of the product were investigated. The morphology and optical properties of Cu2O particles were characterized using scanning electron microscopy, x-ray diffraction, and diffuse reflectance spectra. The synthesized Cu2O nanostructures that formed in the vicinity of the anode at 2 V and pH = 11 showed high uniform distribution, small size, and good electrochemical sensing. These Cu2O nanoparticles were coated on an Indium tin oxide substrate and applied to detect non-enzyme glucose as excellent biosensors. The non-enzyme glucose biosensors exhibited good performance with high response, good selectivity, wide linear detection range, and a low detection limit at 0.4 µM. Synthesized Cu2O nanostructures are potential materials for a non-enzyme glucose biosensor.


Assuntos
Técnicas Biossensoriais/métodos , Cobre/química , Técnicas Eletroquímicas/métodos , Glucose/análise , Nanoestruturas/química , Eletrodos , Polímeros de Fluorcarboneto/química , Concentração de Íons de Hidrogênio , Nanoestruturas/ultraestrutura , Compostos de Estanho/química , Difração de Raios X
15.
BMC Infect Dis ; 18(1): 112, 2018 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-29510687

RESUMO

BACKGROUND: Drug resistant tuberculosis (TB) is increasing in prevalence worldwide. Treatment failure and relapse is known to be high for patients with isoniazid resistant TB treated with standard first line regimens. However, risk factors for unfavourable outcomes and the optimal treatment regimen for isoniazid resistant TB are unknown. This cohort study was conducted when Vietnam used the eight month first line treatment regimen and examined risk factors for failure/relapse among patients with isoniazid resistant TB. METHODS: Between December 2008 and June 2011 2090 consecutive HIV-negative adults (≥18 years of age) with new smear positive pulmonary TB presenting at participating district TB units in Ho Chi Minh City were recruited. Participants with isoniazid resistant TB identified by Microscopic Observation Drug Susceptibility (MODS) had extended follow-up for 2 years with mycobacterial culture to test for relapse. MGIT drug susceptibility testing confirmed 239 participants with isoniazid resistant, rifampicin susceptible TB. Bacterial and demographic factors were analysed for association with treatment failure and relapse. RESULTS: Using only routine programmatic sputum smear microscopy for assessment, (months 2, 5 and 8) 30/239 (12.6%) had an unfavourable outcome by WHO criteria. Thirty-nine patients were additionally detected with unfavourable outcomes during 2 year follow up, giving a total of 69/239 (28.9%) of isoniazid (INH) resistant cases with unfavourable outcome by 2 years of follow-up. Beijing lineage was the only factor significantly associated with unfavourable outcome among INH-resistant TB cases during 2 years of follow-up. (adjusted OR = 3.16 [1.54-6.47], P = 0.002). CONCLUSION: One third of isoniazid resistant TB cases suffered failure/relapse within 2 years under the old eight month regimen. Over half of these cases were not identified by standard WHO recommended treatment monitoring. Intensified research on early identification and optimal regimens for isoniazid resistant TB is needed. Infection with Beijing genotype of TB is a significant risk factor for bacterial persistence on treatment resulting in failure/relapse within 2 years. The underlying mechanism of increased tolerance for standard drug regimens in Beijing genotype strains remains unknown.


Assuntos
Antituberculosos/uso terapêutico , Isoniazida/uso terapêutico , Mycobacterium tuberculosis/efeitos dos fármacos , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Pulmonar/tratamento farmacológico , Adolescente , Adulto , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mycobacterium tuberculosis/genética , Recidiva , Rifampina/uso terapêutico , Fatores de Risco , Escarro/microbiologia , Falha de Tratamento , Vietnã , Adulto Jovem
16.
J Chem Ecol ; 44(7-8): 631-636, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30003401

RESUMO

Leucinodes orbonalis is one of the most damaging insect pests affecting eggplant in the Mekong Delta of Vietnam. While (E)-11-hexadecenyl acetate (E11-16:OAc) and its alcohol, (E)-11-hexadecenol (E11-16:OH), have been identified as major and minor sex pheromone components, respectively, few males were attracted to a blend of these compounds in Vietnamese fields. In order to utilize synthetic pheromone of L. orbonalis as a tool for sustainable pest management programs, we reexamined the pheromone of this species in order to search for other minor components. Gas chromatography-electroantennogram detection and gas chromatography/mass spectrometry analyses of abdominal tip extract revealed the presence of two electroantennogram-active compounds, E11-16:OAc and (3Z,6Z,9Z)-3,6,9-tricosatriene (Z3,Z6,Z9-23:H) in a ratio of 100:2. An extract of the abdomen and thorax showed an additional electroantennogram-active component, (3Z,6Z,9Z)-3,6,9-docosatriene (Z3,Z6,Z9-22:H), with the three compounds (E11-16:OAc, Z3,Z6,Z9-23:H and Z3,Z6,Z9-22:H) being present in a ratio of 100:45:1, indicating that the trienes were mainly present on the cuticular surface. In the field, traps baited with E11-16:OAc and the C23 triene, in a mix of 10:1, caught more male moths than traps baited with the acetate alone. A field evaluation of other polyunsaturated hydrocarbons showed that the C22 triene found in body extract also increased catches when added to the acetate, but no other hydrocarbons did. In contrast, to other studies with this moth, the addition of E11-16:OH to E11-16:OAc plus the C22 or C23 triene, resulted in decreased trap catches.


Assuntos
Hidrocarbonetos/química , Lepidópteros/fisiologia , Atrativos Sexuais/química , Solanum melongena/parasitologia , Acetatos/análise , Animais , Antenas de Artrópodes/fisiologia , Feminino , Frutas/parasitologia , Cromatografia Gasosa-Espectrometria de Massas , Hidrocarbonetos/análise , Masculino , Polienos/análise , Atrativos Sexuais/análise , Comportamento Sexual Animal/fisiologia
17.
J Nanosci Nanotechnol ; 18(4): 2294-2303, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29442895

RESUMO

This paper presents the results of zeta potential, water contact angle, atomic force microscopy image, in vitro solubility, and content of heavy metals in polylactic acid (PLA)/chitosan (CS) nanoparticles loading nifedipine. In addition, the In Vivo test of the PLA/CS nanoparticles loading nifedipine in the mice is also one of highlights of this work. The Zeta potential result shows that the charged surface of the PLA/CS nanoparticles loading nifedipine is neutral, negative or complex depending on nifedipine content. Nifedipine plays a role in increase of hydrophobic property, swelling degree and regular surface as well as decrease of surface rough of the nanoparticles. The PLA/CS/nifedipine nanoparticles are dissolved in the solutions with pH 6.8, pH 4.5 and pH 1.2. The In Vivo test of PLA/CS nanoparticles loading nifedipine on mice was evaluated by the change in diastolic pressure, systolic pressure, arterial pressure and heart rate. The obtained results confirm that the PLA/CS nanoparticles loading nifedipine is suitable to apply in the treatment of hypertension patients lately.


Assuntos
Bloqueadores dos Canais de Cálcio/administração & dosagem , Quitosana/química , Nanopartículas , Nifedipino/administração & dosagem , Poliésteres/química , Animais , Bloqueadores dos Canais de Cálcio/farmacocinética , Humanos , Camundongos , Nifedipino/farmacocinética , Polímeros
18.
Mikrochim Acta ; 186(1): 36, 2018 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-30564967

RESUMO

A method is described for the colorimetric determination of chromate [chromium(VI)]. It is based on the use of graphene oxide (GO) nanoparticles acting as a peroxidase mimic. A blue color is generated by oxidation of 3,3,5,5-tetramethylbenzidine by H2O2 which is catalyzed by GO. This color-forming reaction is prevented in the presence of 8-hydroxyquinoline (8-HQ). However, in the presence of Cr(VI), the blue color will be formed from TMB owing to the oxidation of the inhibitor 8-HQ by Cr(VI). The color can be measured by a spectrophotometry (at 652 nm) or detected visually. Under optimal experimental conditions, response is linear in the 50 to 430 nM range of chromate concentration, and the limit of detection is 5.8 nM (at S/N = 3). The assay is highly selective and was successfully applied to the determination of Cr(VI) in spiked water samples. Graphical abstract Schematic of the colorimetric assay for Cr(VI). TMB: 3,3,5,5-tetramethylbenzidine.

19.
Angew Chem Int Ed Engl ; 57(38): 12483-12488, 2018 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-30091167

RESUMO

An approach to the design of nido-carborane-based luminescent compounds that can exhibit thermally activated delayed fluorescence (TADF) is proposed. 7,8-Dicarba-nido-undecaboranes (nido-carboranes) having various 8-R groups (R=H, Me, i-Pr, Ph) are appended to the meta or para position of the phenyl ring of the dimesitylphenylborane (PhBMes2 ) acceptor, forming donor-acceptor compounds (nido-m1-m4 and nido-p1-p4). The bulky 8-R group and meta substitution of the nido-carborane are essential to attain a highly twisted arrangement between the donor and acceptor moieties, leading to a very small energy splitting between the singlet and triplet excited states (ΔEST <0.05 eV for nido-m2, -m3, and -p3). These compounds exhibit efficient TADF with microsecond-range lifetimes. In particular, nido-m2 and -m3 display aggregation-induced emission (AIE) with TADF properties.

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