Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
1.
Viruses ; 15(3)2023 03 20.
Artículo en Inglés | MEDLINE | ID: mdl-36992498

RESUMEN

A One Health cross-sectoral surveillance approach was implemented to screen biological samples from bats, pigs, and humans at high-risk interfaces for zoonotic viral spillover for five viral families with zoonotic potential in Viet Nam. Over 1600 animal and human samples from bat guano harvesting sites, natural bat roosts, and pig farming operations were tested for coronaviruses (CoVs), paramyxoviruses, influenza viruses, filoviruses and flaviviruses using consensus PCR assays. Human samples were also tested using immunoassays to detect antibodies against eight virus groups. Significant viral diversity, including CoVs closely related to ancestors of pig pathogens, was detected in bats roosting at the human-animal interfaces, illustrating the high risk for CoV spillover from bats to pigs in Viet Nam, where pig density is very high. Season and reproductive period were significantly associated with the detection of bat CoVs, with site-specific effects. Phylogeographic analysis indicated localized viral transmission among pig farms. Our limited human sampling did not detect any known zoonotic bat viruses in human communities living close to the bat cave and harvesting bat guano, but our serological assays showed possible previous exposure to Marburg virus-like (Filoviridae), Crimean-Congo hemorrhagic fever virus-like (Bunyaviridae) viruses and flaviviruses. Targeted and coordinated One Health surveillance helped uncover this viral pathogen emergence hotspot.


Asunto(s)
Quirópteros , Infecciones por Coronavirus , Coronavirus , Filoviridae , Salud Única , Humanos , Animales , Porcinos , Vietnam/epidemiología , Filogenia , Zoonosis
2.
ACS Appl Mater Interfaces ; 14(22): 25397-25408, 2022 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-35608926

RESUMEN

Due to adverse health effects and the broad sources of per- and polyfluoroakyl substances (PFAS), PFAS removal is a critical research area in water purification. We demonstrate the functionalization of thin-film composite (TFC) hollow fiber nanofiltration (HFN) membranes by MXene nanosheets during the interfacial polymerization (IP) process for enhanced removal of perfluorooctane sulfonic acid (PFOS) from water. A MXene-polyamide (PA) selective layer was fabricated on top of a polysulfone (PSF) hollow fiber support via IP of trimesoyl chloride (TMC) and a mixture of piperazine (PIP) and MXene nanosheets to form MXene-PA thin-film nanocomposite (TFN) membranes. Incorporating MXene nanosheets during the IP process tuned the morphology and negative surface charge of the selective layer, resulting in enhanced PFOS rejection from 72% (bare TFC) to more than 96% (0.025 wt % MXene TFN), while the water permeability was also increased from 13.19 (bare TFC) to 29.26 LMH/bar (0.025 wt % MXene TFN). Our results demonstrate that both electrostatic interaction and size exclusion are the main factors governing the PFOS rejection, and both are determined by PA selective layer structural and chemical properties. The lamella structure and interlayer of MXene nanosheets inside the PA layer provided different transport mechanisms for water, ions, and PFAS molecules, resulting in enhanced water permeability and PFAS rejection due to traveling through the membrane by both diffusions through the PA layer and the MXene intralayer channels. MXene nanosheets showed very promising capability as a 2D additive for tuning the structural and chemical properties of the PA layer at the permeability-rejection tradeoff.

3.
Front Public Health ; 10: 826116, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35356028

RESUMEN

Despite the discovery of several closely related viruses in bats, the direct evolutionary progenitor of SARS-CoV-2 has not yet been identified. In this study, we investigated potential animal sources of SARS-related coronaviruses using archived specimens from Sunda pangolins (Manis javanica) and Chinese pangolins (Manis pentadactyla) confiscated from the illegal wildlife trade, and from common palm civets (Paradoxurus hermaphroditus) raised on wildlife farms in Viet Nam. A total of 696 pangolin and civet specimens were screened for the presence of viral RNA from five zoonotic viral families and from Sarbecoviruses using primers specifically designed for pangolin coronaviruses. We also performed a curated data collection of media reports of wildlife confiscation events involving pangolins in Viet Nam between January 2016 and December 2020, to illustrate the global pangolin supply chain in the context of Viet Nam where the trade confiscated pangolins were sampled for this study. All specimens from pangolins and civets sampled along the wildlife supply chains between February 2017 and July 2018, in Viet Nam and tested with conventional PCR assays designed to detect flavivirus, paramyxovirus, filovirus, coronavirus, and orthomyxovirus RNA were negative. Civet samples were also negative for Sarbecoviruses, but 12 specimens from seven live pangolins confiscated in Hung Yen province, northern Viet Nam, in 2018 were positive for Sarbecoviruses. Our phylogenetic trees based on two fragments of the RdRp gene revealed that the Sarbecoviruses identified in these pangolins were closely related to pangolin coronaviruses detected in pangolins confiscated from the illegal wildlife trade in Yunnan and Guangxi provinces, China. Our curated data collection of media reports of wildlife confiscation events involving pangolins in Viet Nam between January 2016 and December 2020, reflected what is known about pangolin trafficking globally. Pangolins confiscated in Viet Nam were largely in transit, moving toward downstream consumers in China. Confiscations included pangolin scales sourced originally from Africa (and African species of pangolins), or pangolin carcasses and live pangolins native to Southeast Asia (predominately the Sunda pangolin) sourced from neighboring range countries and moving through Viet Nam toward provinces bordering China.


Asunto(s)
COVID-19 , Pangolines , Animales , Animales Salvajes , China , Humanos , Filogenia , SARS-CoV-2 , Vietnam/epidemiología
5.
J Pharm Pract ; 33(2): 176-182, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30060679

RESUMEN

Telepharmacy is a rapidly growing area of communication within pharmaceutical care delivery, especially in rural areas. The purpose of this literature review is to determine how telepharmacy is currently being practiced within community and ambulatory pharmacy settings, its effectiveness, and how it is being regulated across the United States. A literature review was performed using PubMed, Ovid MEDLINE, and the Google search engine. State-specific rules were researched using board of pharmacy and legislative online resources. Telepharmacy has been successfully implemented within community pharmacy settings through the creation of remote dispensing sites. The increasing focus of state regulations on telepharmacy services and practices shows the growth and acceptance of this modality of pharmacy practice. There is wide variation among state regulations pertaining to the setup and operation of telepharmacies. Trends in telemedicine show that telepharmaceutical care is likely to continue to expand as it allows for a better allocation of resources and access to more patients. However, research needs to be conducted to specifically analyze the value and place for telepharmacy services.


Asunto(s)
Telemedicina/legislación & jurisprudencia , Telemedicina/tendencias , Servicios Comunitarios de Farmacia , Prescripciones de Medicamentos , Accesibilidad a los Servicios de Salud , Humanos , Derivación y Consulta , Gobierno Estatal , Estados Unidos
6.
J Food Biochem ; 44(3): e13143, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31910490

RESUMEN

Rhodomyrtus tomentosa was reported to contain various bioactive metabolites, especially phenolic compounds. In the present study, the suppressive activity of phenolic compound from R. tomentosa fruits on mast cell activation was investigated in vitro. The result showed that myricetin was isolated from R. tomentosa fruits and its characterization was identified by nuclear magnetic resonance spectroscopy. Notably, myricetin was found to be effective in inhibition of mast cell degranulation by attenuating the release of ß-hexosaminidase and the elevation of intracellular calcium. Moreover, myricetin exhibited inhibitory effect on the production of IL-4 and Tumor necrosis factor alpha (TNF-α) in a concentration-dependent manner. Furthermore, high antioxidant activity of myricetin due to scavenging 1,1-diphenyl-2-picryl-hydrazyl (DPPH) and ABTS+ radicals was also evidenced. Notably, the activation of FcɛRI-mediated signaling molecules including Syk, PLCγ, and NF-κB was also suppressed by myricetin treatment. Accordingly, myricetin from R. tomentosa fruits could be suggested as a functional food for the amelioration of allergic diseases. PRACTICAL APPLICATIONS: Polyphenol have been shown to exert various biological activities and health beneficial effects. Results from the present study revealed that myricetin from R. tomentosa fruits possesses the inhibitory effect on allergic response in mast cells. Therefore, myricetin from R. tomentosa fruits could be developed as a functional ingredient for the amelioration of allergic diseases.


Asunto(s)
Frutas , Myrtaceae , Regulación hacia Abajo , Flavonoides , Mastocitos
7.
PLoS One ; 15(8): e0237129, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32776964

RESUMEN

Outbreaks of emerging coronaviruses in the past two decades and the current pandemic of a novel coronavirus (SARS-CoV-2) that emerged in China highlight the importance of this viral family as a zoonotic public health threat. To gain a better understanding of coronavirus presence and diversity in wildlife at wildlife-human interfaces in three southern provinces in Viet Nam 2013-2014, we used consensus Polymerase Chain Reactions to detect coronavirus sequences. In comparison to previous studies, we observed high proportions of positive samples among field rats (34.0%, 239/702) destined for human consumption and insectivorous bats in guano farms (74.8%, 234/313) adjacent to human dwellings. Most notably among field rats, the odds of coronavirus RNA detection significantly increased along the supply chain from field rats sold by traders (reference group; 20.7% positivity, 39/188) by a factor of 2.2 for field rats sold in large markets (32.0%, 116/363) and 10.0 for field rats sold and served in restaurants (55.6%, 84/151). Coronaviruses were also detected in rodents on the majority of wildlife farms sampled (60.7%, 17/28). These coronaviruses were found in the Malayan porcupines (6.0%, 20/331) and bamboo rats (6.3%, 6/96) that are raised on wildlife farms for human consumption as food. We identified six known coronaviruses in bats and rodents, clustered in three Coronaviridae genera, including the Alpha-, Beta-, and Gammacoronaviruses. Our analysis also suggested either mixing of animal excreta in the environment or interspecies transmission of coronaviruses, as both bat and avian coronaviruses were detected in rodent feces on wildlife farms. The mixing of multiple coronaviruses, and their apparent amplification along the wildlife supply chain into restaurants, suggests maximal risk for end consumers and likely underpins the mechanisms of zoonotic spillover to people.


Asunto(s)
Animales Salvajes/virología , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/transmisión , Coronavirus/genética , Carne/virología , Zoonosis/epidemiología , Zoonosis/transmisión , Animales , Quirópteros/virología , Infecciones por Coronavirus/diagnóstico , Infecciones por Coronavirus/virología , Reservorios de Enfermedades/virología , Heces/virología , Abastecimiento de Alimentos , Humanos , Filogenia , Reacción en Cadena de la Polimerasa , Puercoespines/virología , ARN Viral/genética , Ratas , Riesgo , Vietnam/epidemiología , Zoonosis/diagnóstico , Zoonosis/virología
8.
Chem Asian J ; 12(21): 2819-2826, 2017 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-28569412

RESUMEN

Mono-, di-, tri-, and tetraarylated thieno[3,2-b]thiophenes were synthesized by direct site-selective Pd-catalyzed C-H activation reactions with various aryl bromides in the presence of a phosphine-free Pd(OAc)2 /KOAc catalyst system in N,N-dimethylacetamide (DMAc). The arylation of 2-arylthieno[3,2-b]thiophene took place at the C3 position if the 2-aryl substituents possessed electron-withdrawing groups and at the C5 position if they were bulky and possessed electron-donating groups.

9.
J Mol Graph Model ; 71: 135-153, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27914300

RESUMEN

Dihydrofolate reductase (DHFR), a key enzyme in tetrahydrofolate-mediated biosynthetic pathways, has a structural motif known to be highly conserved over a wide range of organisms. Given its critical role in purine and amino acid synthesis, DHFR is a well established therapeutic target for treating a wide range of prokaryotic and eukaryotic infections as well as certain types of cancer. Here we present a structural-based computer analysis of bacterial (Bacilli) and plasmid DHFR evolution. We generated a structure-based sequence alignment using 7 wild-type DHFR x-ray crystal structures obtained from the RCSB Protein Data Bank and 350 chromosomal and plasmid homology models we generated from sequences obtained from the NCBI Protein Database. We used these alignments to compare active site and non-active site conservation in terms of amino acid residues, secondary structure and amino acid residue class. With respect to amino acid sequences and residue classes, active-site positions in both plasmid and chromosomal DHFR are significantly more conserved than non-active site positions. Secondary structure conservation was similar for active site and non-active site positions. Plasmid-encoded DHFR proteins have greater degree of sequence and residue class conservation, particularly in sequence positions associated with a network of concerted protein motions, than chromosomal-encoded DHFR proteins. These structure-based were used to build DHFR specific phylogenetic trees from which evidence for horizontal gene transfer was identified.


Asunto(s)
Evolución Molecular , Conformación Proteica , Homología Estructural de Proteína , Tetrahidrofolato Deshidrogenasa/química , Secuencia de Aminoácidos/genética , Bacillus/química , Bacillus/genética , Sitios de Unión , Dominio Catalítico/genética , Cristalografía por Rayos X , Modelos Moleculares , Filogenia , Plásmidos/química , Plásmidos/genética , Estructura Secundaria de Proteína , Alineación de Secuencia , Tetrahidrofolato Deshidrogenasa/metabolismo
10.
Vaccine ; 33(24): 2778-85, 2015 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-25917677

RESUMEN

Early protection with a high potency (>6PD50) foot-and-mouth disease (FMD) O1 Manisa (Middle-East South Asia lineage) vaccine against challenge with O/VIT/2010 (O Mya98 lineage) was tested in pigs. Only two pigs that were vaccinated seven days prior to challenge had any demonstrable antibodies as a result of vaccination at the time of challenge. However, 80% and 60% of pigs that were vaccinated seven and four days prior to coronary band challenge were protected. Vaccination significantly reduced the amount of virus excreted in nasal swabs, saliva and faeces compared to unvaccinated and infected controls. Virus and viral RNA could be detected in some pigs until termination of the experiment 14 days after challenge. Antibodies to the non-structural proteins (NSP) were detected in only one pig that was challenged four days post vaccination (dpv) and transiently in two pigs that were challenged sevendpv at only one time point. For each vaccine and control group, a group of unvaccinated pigs were kept in the same room but with no direct contact with the infected pigs to determine whether vaccination prevented transmission. Despite the presence of live virus and viral RNA in these indirect contact pigs, the groups in contact with the vaccinated and infected pigs did not develop clinical signs nor did they sero-convert. Contact pigs in the same room as unvaccinated challenged controls did show signs of disease and virus infection that resulted in sero-conversion to the NSP. A breach of the wall that separated the two groups at nine days post challenge might have contributed to this finding. This study showed that high potency vaccine can provide protection to pigs soon after vaccination and that aerosol transmission within rooms is a rare event.


Asunto(s)
Virus de la Fiebre Aftosa/inmunología , Fiebre Aftosa/prevención & control , Sus scrofa/inmunología , Enfermedades de los Porcinos/prevención & control , Potencia de la Vacuna , Vacunas Virales/inmunología , Animales , Anticuerpos Antivirales/inmunología , Heces/virología , Fiebre Aftosa/transmisión , Virus de la Fiebre Aftosa/genética , Virus de la Fiebre Aftosa/aislamiento & purificación , ARN Viral/genética , ARN Viral/aislamiento & purificación , Saliva/virología , Porcinos , Enfermedades de los Porcinos/virología , Vacunación/veterinaria , Vacunas Virales/administración & dosificación , Viremia/virología
11.
Org Lett ; 12(10): 2406-9, 2010 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-20429533

RESUMEN

Substitution of the fluoro or methoxy group in unprotected 2-fluoro- and 2-methoxybenzoic acids to afford N-aryl and N-alkyl anthranilic acids occurs upon reaction with lithioamides under mild conditions in the absence of a metal catalyst.


Asunto(s)
Amidas/química , Benzoatos/química , Litio/química , Compuestos Organometálicos/química , ortoaminobenzoatos/síntesis química , Estructura Molecular , Estereoisomerismo , ortoaminobenzoatos/química
12.
J Biomol Tech ; 13(4): 199-204, 2002 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19498985

RESUMEN

A series of successful microarray experiments typically results in a data matrix containing a list of a few thousand genes and their measured expression values across various conditions tested. The understanding of why some genes are clustered in their expression pattern can be greatly facilitated by gathering all prior knowledge about all the genes in a given cluster. Here we demonstrate a strategy using the NCI60 data set (Scherf U, Ross DT,Waltham M, et al., Nature Genet 2000;24(3):236-244) on a cluster of genes highly expressed in the melanoma cell lines. By traversing public databases using cross-references between the databases,we show that the Gene Ontology (GO) classifications of some of the genes are consistent with their products' involvement in melanin biosynthesis.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA