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1.
mBio ; 14(5): e0045123, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37623322

RESUMO

IMPORTANCE: The relevance of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) ORF8 in the pathogenesis of COVID-19 is unclear. Virus natural isolates with deletions in ORF8 were associated with wild milder disease, suggesting that ORF8 might contribute to SARS-CoV-2 virulence. This manuscript shows that ORF8 is involved in inflammation and in the activation of macrophages in two experimental systems: humanized K18-hACE2 transgenic mice and organoid-derived human airway cells. These results identify ORF8 protein as a potential target for COVID-19 therapies.


Assuntos
COVID-19 , SARS-CoV-2 , Camundongos , Animais , Humanos , SARS-CoV-2/genética , Fatores de Virulência/genética , Sistema Respiratório , Camundongos Transgênicos
2.
J Virol ; 96(17): e0072322, 2022 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-35975999

RESUMO

The production of type I interferon (IFN) is the hallmark of the innate immune response. Most, if not all, mammalian viruses have a way to circumvent this response. Fundamental knowledge on viral evasion of innate immune responses may facilitate the design of novel antiviral therapies. To investigate how human metapneumovirus (HMPV) interacts with the innate immune response, recombinant viruses lacking G, short hydrophobic (SH), or M2-2 protein expression were assessed for IFN induction in A549 cells. HMPV lacking G or SH protein expression induced similarly low levels of IFN, compared to the wild-type virus, whereas HMPV lacking M2-2 expression induced significantly more IFN than the wild-type virus. However, sequence analysis of the genomes of M2-2 mutant viruses revealed large numbers of mutations throughout the genome. Over 70% of these nucleotide substitutions were A-to-G and T-to-C mutations, consistent with the properties of the adenosine deaminase acting on RNA (ADAR) protein family. Knockdown of ADAR1 by CRISPR interference confirmed the role of ADAR1 in the editing of M2-2 deletion mutant virus genomes. More importantly, Northern blot analyses revealed the presence of defective interfering RNAs (DIs) in M2-2 mutant viruses and not in the wild-type virus or G and SH deletion mutant viruses. DIs are known to be potent inducers of the IFN response. The presence of DIs in M2-2 mutant virus stocks and hypermutated virus genomes interfere with studies on HMPV and the innate immune response and should be addressed in future studies. IMPORTANCE Understanding the interaction between viruses and the innate immune response is one of the barriers to the design of antiviral therapies. Here, we investigated the role of the G, SH, and M2-2 proteins of HMPV as type I IFN antagonists. In contrast to other studies, no IFN-antagonistic functions could be observed for the G and SH proteins. HMPV with a deletion of the M2-2 protein did induce type I IFN production upon infection of airway epithelial cells. However, during generation of virus stocks, these viruses rapidly accumulated DIs, which are strong activators of the type I IFN response. Additionally, the genomes of these viruses were hypermutated, which was prevented by generating stocks in ADAR knockdown cells, confirming a role for ADAR in hypermutation of HMPV genomes or DIs. These data indicate that a role of the HMPV M2-2 protein as a bona fide IFN antagonist remains elusive.


Assuntos
Imunidade Inata , Interferon Tipo I , Metapneumovirus , Proteínas Virais , Células A549 , Adenosina Desaminase , Antivirais/metabolismo , Humanos , Interferon Tipo I/antagonistas & inibidores , Interferon Tipo I/imunologia , Metapneumovirus/genética , Metapneumovirus/metabolismo , Proteínas de Ligação a RNA , Proteínas Virais/genética , Proteínas Virais/metabolismo
3.
AJNR Am J Neuroradiol ; 42(9): 1676-1682, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34244129

RESUMO

BACKGROUND AND PURPOSE: Second opinion reports of neurologic head and neck imaging are requested with increased regularity, and they may contain a recommendation to the clinician. Our aim was to investigate the frequency and determinants of the presence of a recommendation and the adherence by the referring physician to the recommendation in a second opinion neurology head and neck imaging report and the diagnostic yield of these recommendations. MATERIALS AND METHODS: This retrospective study included 994 consecutive second opinion reports of neurology head and neck imaging examinations performed at a tertiary care center. RESULTS: Of the 994 second opinion reports, 12.2% (121/994) contained a recommendation. An oncologic imaging indication was significantly (P = .030) associated with a lower chance of a recommendation in the second opinion report (OR = .67; 95% CI, 0.46-0.96). Clinicians followed 65.7% (88/134) of the recommendations. None of the investigated variables (patient age, sex, hospitalization status, indication for the second opinion report, experience of the radiologist who signed the second opinion report, strength of the recommendation, and whether the recommendation was made due to apparent quality issues of the original examination) were significantly associated with the compliance of the referring physician to this recommendation. The 134 individual recommendations eventually led to the establishment of 52 (38.2%) benign diagnoses and 28 (20.6%) malignant diagnoses, while no definitive diagnosis could be established in 56 (41.2%) cases. CONCLUSIONS: Recommendations are relatively common in second opinion reports of neurology head and neck imaging examinations, though less for oncologic indications. They are mostly followed by requesting physicians, thus affecting patient management. In most cases, they also lead to the establishment of a diagnosis, hence adding value to patient care.


Assuntos
Médicos , Encaminhamento e Consulta , Humanos , Radiologistas , Estudos Retrospectivos
4.
mSphere ; 6(3)2021 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-33980679

RESUMO

Human respiratory syncytial virus (HRSV) is the leading cause of bronchiolitis in infants. Two subgroups of HRSV (A and B) routinely cocirculate. Most research has been performed with HRSV-A strains because these are easier to culture than HRSV-B strains. In this study, we aimed to compare the replicative fitness and HRSV-induced innate cytokine responses of HRSV-A and HRSV-B strains in disease-relevant cell culture models. We used two recombinant (r) clinical isolate-based HRSV strains (A11 and B05) and one recombinant laboratory-adapted HRSV strain (A2) to infect commercially available nasal, bronchial, and small-airway cultures. Epithelial cells from all anatomical locations were susceptible to HRSV infection despite the induction of a dominant type III interferon response. Subgroup A viruses disseminated and replicated faster than the subgroup B virus. Additionally, we studied HRSV infection and innate responses in airway organoids (AOs) cultured at air-liquid interface (ALI). Results were similar to the commercially obtained bronchial cells. In summary, we show that HRSV replicates well in cells from both the upper and the lower airways, with a slight replicative advantage for subgroup A viruses. Lastly, we showed that AOs cultured at ALI are a valuable model for studying HRSV ex vivo and that they can be used in the future to study factors that influence HRSV disease severity.IMPORTANCE Human respiratory syncytial virus (HRSV) is the major cause of bronchiolitis and pneumonia in young infants and causes almost 200,000 deaths per year. Currently, there is no vaccine or treatment available, only a prophylactic monoclonal antibody (palivizumab). An important question in HRSV pathogenesis research is why only a fraction (1 to 3%) of infants develop severe disease. Model systems comprising disease-relevant HRSV isolates and accurate and reproducible cell culture models are indispensable to study infection, replication, and innate immune responses. Here, we used differentiated AOs cultured at ALI to model the human airways. Subgroup A viruses replicated better than subgroup B viruses, which we speculate fits with epidemiological findings that subgroup A viruses cause more severe disease in infants. By using AOs cultured at ALI, we present a highly relevant, robust, and reproducible model that allows for future studies into what drives severe HRSV disease.


Assuntos
Brônquios/virologia , Nariz/virologia , Organoides/microbiologia , Vírus Sincicial Respiratório Humano/genética , Vírus Sincicial Respiratório Humano/fisiologia , Replicação Viral , Brônquios/citologia , Citocinas/análise , Citocinas/imunologia , Células Epiteliais/virologia , Humanos , Imunidade Inata , Técnicas In Vitro , Cinética , Nariz/citologia , Vírus Sincicial Respiratório Humano/classificação , Vírus Sincicial Respiratório Humano/imunologia
5.
Braz J Med Biol Res ; 54(3): e10504, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33503201

RESUMO

Molecular changes that affect mitochondrial glycolysis have been associated with the maintenance of tumor cells. Some metabolic factors have already been described as predictors of disease severity and outcomes. This systematic review was conducted to answer the question: Is the glycolytic pathway correlated with the prognosis of oral squamous cell carcinoma (OSCC)? A search strategy was developed to retrieve studies in English from PubMed, Scopus, and ISI Web of Science using keywords related to squamous cell carcinoma, survival, and glycolytic pathway, with no restriction of publication date. The search retrieved 1273 publications. After the titles and abstracts were analyzed, 27 studies met inclusion criteria. Studies were divided into groups according to two subtopics, glycolytic pathways and diagnosis, which describe the glycolytic profile of OSCC tumors. Several components of tumor energy metabolism found in this review are important predictors of survival of patients with OSCC.


Assuntos
Glicólise , Neoplasias Bucais/diagnóstico , Carcinoma de Células Escamosas de Cabeça e Pescoço/diagnóstico , Humanos , Neoplasias Bucais/metabolismo , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo
6.
Braz. j. med. biol. res ; 54(3): e10504, 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1153517

RESUMO

Molecular changes that affect mitochondrial glycolysis have been associated with the maintenance of tumor cells. Some metabolic factors have already been described as predictors of disease severity and outcomes. This systematic review was conducted to answer the question: Is the glycolytic pathway correlated with the prognosis of oral squamous cell carcinoma (OSCC)? A search strategy was developed to retrieve studies in English from PubMed, Scopus, and ISI Web of Science using keywords related to squamous cell carcinoma, survival, and glycolytic pathway, with no restriction of publication date. The search retrieved 1273 publications. After the titles and abstracts were analyzed, 27 studies met inclusion criteria. Studies were divided into groups according to two subtopics, glycolytic pathways and diagnosis, which describe the glycolytic profile of OSCC tumors. Several components of tumor energy metabolism found in this review are important predictors of survival of patients with OSCC.


Assuntos
Humanos , Neoplasias Bucais/diagnóstico , Carcinoma de Células Escamosas de Cabeça e Pescoço/diagnóstico , Glicólise , Neoplasias Bucais/metabolismo , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo
7.
Int Endod J ; 52(12): 1750-1757, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31356685

RESUMO

AIM: To describe an in vitro experimental model of cystic structure formation to conduct research on radicular cyst development. METHODOLOGY: To form spheroid structures, various numbers (1 × 104 , 5 × 104 or 1 × 105 ) of epithelial cells (HaCaT and Cal27) were seeded in 96-well plates previously coated with 1.5% low-melting agarose. After 24 h, the spheroids were collected, embedded in 3D collagen matrix and transferred to 24-well plates previously coated with polymerized collagen and kept for up to 21 days. Images of spheroids were captured at each time-point (1, 5, 9, 15 and 21 days), and samples underwent histological and confocal microscopy analyses. Spheroid area, perimeter and cell dispersion were measured. One-way Anova was used for statistical analysis. RESULTS: Both epithelial cell lines were able to generate regular and circular spheroids after 24 h of incubation regardless of cell density. Spheroid structures in the collagen matrix were uniform in most samples until day 15, when several spots that appeared to be new cultures were seen. Spheroids from HaCaT were significantly more stable than those from Cal27 (P < 0.05). Starting on the third day, the examination of histological sections revealed a cavity with epithelial lining morphology, similar to a pathological radicular cyst. CONCLUSIONS: This study describes an experimental model of cystogenesis in vitro that may be used to test theories and investigates the effects of different growth factors during cyst development and maintenance.


Assuntos
Colágeno , Esferoides Celulares , Linhagem Celular , Células Epiteliais
8.
Med Oral Patol Oral Cir Bucal ; 24(3): e346-e353, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31011146

RESUMO

BACKGROUND: The present study attempted to provide information regarding non-muscle myosin II (MII) isoforms immunoreactivity in patients with head and neck squamous cell carcinoma (HNSCC) and analysis of the patients' clinical status after 5 years of monitoring. MATERIAL AND METHODS: A semiquantitative analysis of the immunoreactivity of the MII isoforms was performed in 54 surgical specimens and its correlation with clinical and pathological variables and prognosis was verified. Data were analyzed using chi-square, Mann-Whitney and Kruskal-Wallis tests. To evaluate the survival over the total monitoring time and any connection with the proteins studied, the Kaplan-Meier analysis was used. P values ≤0.05 were considered statistically significant. RESULTS: In the advanced stages of pathological tumor-node-metastasis, the expression of MIIB in adjacent non-neoplastic epithelial tissues tended to increase (p = 0.057). In tumoral zones there was an association of high expression among the three isoforms (MIIA/MIIB p=0,001, MIIB/MIIC p=0,006 and MIIA/MIIC p=0,012). Negative clinical evolution in patients was directly correlated to increased MIIC expression in the tumoral zone of invasion in HNSCC (p = 0.017). Based on clinical evolution after the monitoring period, patients with tumors expressing MIIC had poorer prognoses (p = 0.048). CONCLUSIONS: The present study suggests that MIIB expression in non-neoplastic adjacent epithelial tissues may indicate a potential for regional metastasis and that MIIC expression in the tumoral zone of invasion is predictive of negative evolution of the disease.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Carcinoma de Células Escamosas de Cabeça e Pescoço , Biomarcadores Tumorais , Humanos , Miosina Tipo II , Prognóstico
9.
Toxicon ; 162: 32-39, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30849455

RESUMO

Lonomia obliqua is a caterpillar of potential therapeutic interest whose venom is able to induce severe blood leakage and modulate leukocyte migration. Since both phenotypes are associated with changes in cytoskeleton dynamics and cell adhesion properties, the aim of this study was to analyze the effects of Lonomia obliqua bristle extract (LOBE) in cell adhesion and migration signaling. Proteomic analysis revealed that epithelial cells (CHO-K1) exposed to LOBE (30 µg/mL, 30 min) exhibited changes in levels of actin regulatory proteins, including RhoGTPases. These changes correlated with an increase in the activity of the RhoGTPase family member Rac as measured by Förster resonance energy transfer (FRET). When plated in migration promoting conditions, CHO-K1 cells exposed to LOBE (10 µg/mL) showed an increase in membrane ruffling after short (30 min) period of incubation that was accompanied by changes in the distribution of the adhesion markers paxillin, vinculin and an increase of focal adhesion kinase autophosphorylation levels (Y397), suggesting changes in cell-extracellular matrix (ECM) adhesion properties and signaling. These data suggest that LOBE possesses bioactive molecules that are capable to modulated cell migration signaling, cytoskeletal dynamics and cell-ECM properties of several cell types.


Assuntos
Venenos de Artrópodes/toxicidade , Adesão Celular/efeitos dos fármacos , Mariposas/química , Proteínas rac1 de Ligação ao GTP/metabolismo , Actinas/metabolismo , Animais , Células CHO , Movimento Celular/efeitos dos fármacos , Cricetulus , Citoesqueleto/fisiologia , Larva/química , Paxilina/metabolismo , Fosforilação , Proteoma/análise , Vinculina/metabolismo
10.
J Environ Manage ; 165: 298-312, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26431614

RESUMO

Pesticide application rates are high and increasing in upland agricultural systems in Thailand producing vegetables, fruits and ornamental crops, leading to the pollution of stream water with pesticide residues. The objective of this study was to determine the maximum per hectare application rates of two widely used pesticides that would achieve non-hazardous pesticide concentrations in the stream water and to evaluate how farm household incomes would be affected if farmers complied with these restricted application rates. For this purpose we perform an integrated modeling approach of a hydrological solute transport model (the Soil and Water Assessment Tool, SWAT) and an agent-based farm decision model (Mathematical Programming-based Multi-Agent Systems, MPMAS). SWAT was used to simulate the pesticide fate and behavior. The model was calibrated to a 77 km(2) watershed in northern Thailand. The results show that to stay under a pre-defined eco-toxicological threshold, the current average application of chlorothalonil (0.80 kg/ha) and cypermethrin (0.53 kg/ha) would have to be reduced by 80% and 99%, respectively. The income effect of such reductions was simulated using MPMAS. The results suggest that if farm households complied with the application thresholds then their income would reduce by 17.3% in the case of chlorothalonil and by 38.3% in the case of cypermethrin. Less drastic income effects can be expected if methods of integrated pest management were more widely available. The novelty of this study is to combine two models from distinctive disciplines to evaluate pesticide reduction scenarios based on real-world data from a single study site.


Assuntos
Agricultura/economia , Modelos Teóricos , Controle de Pragas/métodos , Resíduos de Praguicidas/análise , Poluentes Químicos da Água/análise , Água/química , Agricultura/métodos , Tomada de Decisões , Nitrilas/análise , Nitrilas/química , Resíduos de Praguicidas/química , Piretrinas/análise , Piretrinas/química , Solo/química , Tailândia , Movimentos da Água , Poluentes Químicos da Água/química , Abastecimento de Água
11.
Rev Sci Tech ; 35(3): 905-911, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28332641

RESUMO

The newly identified Middle East respiratory syndrome coronavirus (MERS-CoV), which causes severe respiratory disease, particularly in people with comorbidities, requires further investigation. Studies in Qatar and elsewhere have provided evidence that dromedary camels are a reservoir for the virus, but the exact modes of transmission of MERS-CoV to humans remain unclear. In February 2014, an assessment was made of the suitability and sensitivity of different types of sample for the detection of MERSCoV by real-time reverse-transcription polymerase chain reaction (RT-PCR) for three gene targets: UpE (upstream of the E gene), the N (nucleocapsid) gene and open reading frame (ORF) 1a. Fifty-three animals presented for slaughter were sampled. A high percentage of the sampled camels (79% [95% confidence interval 66.9-91.5%, standard error 0.0625]; 42 out of 53) were shown to be shedding MERS-CoV at the time of slaughter, yet all the animals were apparently healthy. Among the virus-positive animals, nasal swabs were most often positive (97.6%). Oral swabs were the second most frequently positive (35.7%), followed by rectal swabs (28.5%). In addition, the highest viral load, expressed as a cycle threshold (Ct) value of 11.27, was obtained from a nasal swab. These findings lead to the conclusion that nasal swabs are the candidate sample of choice for detecting MERS-CoV using RT-PCR technology in apparently healthy camels.


Des travaux de recherche approfondis sont encore nécessaires concernant le coronavirus responsable du syndrome respiratoire du Moyen-Orient (MERSCoV), un virus identifié récemment et qui provoque des troubles respiratoires sévères en particulier chez les individus atteints de pathologies multiples. Les études effectuées au Qatar et ailleurs ont démontré que les dromadaires font office de réservoirs du virus ; toutefois, les modalités précises de la transmission du MERS-CoV à l'être humain demeurent obscures. En février 2014, une équipe de chercheurs a évalué l'adéquation et la sensibilité de plusieurs types d'échantillons pour détecter le MERS-CoV en utilisant l'amplification en chaîne par polymérase couplée à une transcription inverse en temps réel (RT-PCR) spécifique pour trois cibles génétiques, à savoir la séquence UpE (en amont du gène E), le gène N (nucléocapside) et le cadre de lecture ORF1a. Pour ce faire, divers prélèvements ont été effectués sur 53 dromadaires destinés à l'abattage. Un fort pourcentage de ces dromadaires (79 % [intervalle de confiance à 95 % compris entre 66,9 et 91,5 %, erreur standard : 0,0625], soit 42 sur 53) excrétaient le MERSCoV au moment de l'abattage, mais aucun ne présentait le moindre signe clinique. Les échantillons dans lesquels le plus de cas positifs ont été détectés étaient les écouvillons nasaux (97,6 %). Venaient ensuite les écouvillons oraux, qui ont détecté 35,7 % de cas positifs, puis les écouvillons rectaux (28,5 % de cas positifs détectés). Par ailleurs, ce sont les écouvillons nasaux qui ont permis d'obtenir l'intensité la plus élevée de la réponse de la RT-PCR, exprimée en une valeur du seuil de cycles de 11,27. Ces résultats permettent de conclure que les écouvillons nasaux sont les échantillons à privilégier pour la détection du MERS-CoV par RTPCR chez les dromadaires asymptomatiques.


Es preciso investigar más a fondo el coronavirus del síndrome respiratorio de Oriente Medio (MERS-CoV), recién identificado, que provoca una grave enfermedad respiratoria, sobre todo en personas con afecciones concomitantes. Estudios realizados en Qatar y otros lugares han deparado pruebas de que los dromedarios son un reservorio del virus, pero aún no están del todo claros los modelos exactos de transmisión del MERS-CoV al ser humano. Los autores describen un análisis realizado en febrero de 2014 de la idoneidad y sensibilidad de distintos tipos de muestra para detectar el MERS-CoV mediante una reacción en cadena de la polimerasa acoplada a transcripción inversa en tiempo real (RTPCR) dirigida contra tres genes: el gen UpE (upstream of the E gene: en dirección 5' desde el gen E); el gen N (nucleocápside) y el marco de lectura abierto (ORF) 1a. Para ello se tomaron muestras de 53 animales enviados al sacrificio. Se comprobó que un elevado porcentaje de los dromedarios analizados (un 79% [intervalo de confianza al 95%: 66,9­91,5%; error estándar: 0,0625], esto es, 42 de 53) excretaban virus en el momento del sacrificio, pese a que todos los animales parecían estar sanos. Entre los ejemplares positivos para el MERS-CoV, las muestras que con más frecuencia arrojaban resultado positivo eran los frotis nasales (97,6%). Las segundas, por orden de frecuencia, eran los frotis bucales (35,7%), seguidos de los frotis rectales (28,5%). Además, la carga viral más alta, expresada por un valor de ciclo umbral (Ct) (o punto de cruce) de 11,27, se obtuvo a partir de un frotis nasal. Estos resultados llevan a la conclusión de que los frotis nasales son el tipo de muestra más adaptado para detectar el MERS-CoV en dromedarios aparentemente sanos mediante la técnica de RT-PCR.


Assuntos
Camelus , Infecções por Coronavirus/veterinária , Coronavírus da Síndrome Respiratória do Oriente Médio/isolamento & purificação , Fatores Etários , Animais , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Reservatórios de Doenças , Humanos , Coronavírus da Síndrome Respiratória do Oriente Médio/genética , Boca/virologia , Mucosa Nasal/virologia , Roupa de Proteção , Catar/epidemiologia , RNA Viral/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Reto/virologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Fatores de Risco , Carga Viral/veterinária , Eliminação de Partículas Virais
12.
Environ Pollut ; 191: 70-9, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24811948

RESUMO

The application of agrochemicals in Southeast Asia is increasing in rate, variety and toxicity with alarming speed. Understanding the behavior of these different contaminants within the environment require comprehensive monitoring programs as well as accurate simulations with hydrological models. We used the SWAT hydrological model to simulate the fate of three different pesticides, one of each usage type (herbicide, fungicide and insecticide) in a mountainous catchment in Northern Thailand. Three key parameters were identified: the sorption coefficient, the decay coefficient and the coefficient controlling pesticide percolation. We yielded satisfactory results simulating pesticide load dynamics during the calibration period (NSE: 0.92-0.67); the results during the validation period were also acceptable (NSE: 0.61-0.28). The results of this study are an important step in understanding the modeling behavior of these pesticides in SWAT and will help to identify thresholds of worst-case scenarios in order to assess the risk for the environment.


Assuntos
Modelos Químicos , Praguicidas/química , Simulação por Computador , Tailândia , Movimentos da Água , Poluentes Químicos da Água/análise
13.
Dis Aquat Organ ; 108(2): 137-47, 2014 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-24553419

RESUMO

Effects of dissolved pesticides on fish are widely described, but little is known about effects of pesticide-contaminated feeds taken up orally by fish. In integrated farms, pesticides used on crops may affect grass carp that feed on plants from these fields. In northern Vietnam, grass carp suffer seasonal mass mortalities which may be caused by pesticide-contaminated plants. To test effects of pesticide-contaminated feeds on health and bioaccumulation in grass carp, a net-cage trial was conducted with 5 differently contaminated grasses. Grass was spiked with 2 levels of trichlorfon/fenitrothion and fenobucarb. Unspiked grass was used as a control. Fish were fed at a daily rate of 20% of body mass for 10 d. The concentrations of fenitrothion and fenobucarb in pond water increased over time. Effects on fish mortality were not found. Fenobucarb in feed showed the strongest effects on fish by lowering feed uptake, deforming the liver, increasing blood glucose and reducing cholinesterase activity in blood serum, depending on feed uptake. Fenobucarb showed increased levels in flesh in all treatments, suggesting bio-concentration. Trichlorfon and fenitrothion did not significantly affect feed uptake but showed concentration-dependent reduction of cholinesterase activity and liver changes. Fenitrothion showed bioaccumulation in flesh which was dependant on feed uptake, whereas trichlorfon was only detected in very low concentrations in all treatments. Pesticide levels were all detected below the maximum residue levels in food. The pesticide-contaminated feeds tested did not cause mortality in grass carp but were associated with negative physiological responses and may increase susceptibility to diseases.


Assuntos
Ração Animal/análise , Carpas , Inseticidas/toxicidade , Animais , Carbamatos/administração & dosagem , Carbamatos/farmacocinética , Carbamatos/toxicidade , Comportamento Alimentar , Fenitrotion/administração & dosagem , Fenitrotion/farmacocinética , Fenitrotion/toxicidade , Doenças dos Peixes/induzido quimicamente , Inseticidas/farmacocinética , Triclorfon/administração & dosagem , Triclorfon/farmacocinética , Triclorfon/toxicidade , Poluentes Químicos da Água/toxicidade , Aumento de Peso/efeitos dos fármacos
14.
Neth J Med ; 71(7): 377-85, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24038567

RESUMO

In this new Dutch guideline for hepatitis C virus infection we provide recommendations for the management of hepatitis C infection. Until 2012 the standard for treatment consisted of pegylated interferon alpha (peg-IFNa) and ribavirin. The advent of first-generation direct antiviral agents such as boceprevir and telaprevir has changed the concept of treatment of adult chronic hepatitis C genotype 1 infected patients. There are three benefits of boceprevir and telaprevir. They increase the likelihood of cure in 1) naive genotype 1 patients and 2) in patients who did not respond to earlier treatment with peg-IFNa and ribavirin, while 3) allowing shortening of treatment duration from 48 weeks to 24 or 28 weeks, which is possible in 40-60% of non-cirrhotic naive (boceprevir and telaprevir) and relapsing patients (telaprevir). The use of boceprevir and telaprevir is associated with multiple side effects and awareness of these side effects is needed to guide the patient through the treatment process. This guideline, formulated on behalf of The Netherlands Association of Hepato-gastroenterologists, The Netherlands Association of Internal Medicine, and The Dutch Association for the Study of Liver Disease, serves as a manual for physicians for the management and treatment of acute and chronic hepatitis C virus monoinfection in adults.


Assuntos
Antivirais/uso terapêutico , Hepacivirus , Hepatite C Crônica/tratamento farmacológico , Oligopeptídeos/uso terapêutico , Prolina/análogos & derivados , Adulto , Antivirais/efeitos adversos , Interações Medicamentosas , Genótipo , Hepacivirus/genética , Humanos , Interferon alfa-2 , Interferon-alfa/uso terapêutico , Países Baixos , Oligopeptídeos/efeitos adversos , Polietilenoglicóis/uso terapêutico , Prolina/efeitos adversos , Prolina/uso terapêutico , Proteínas Recombinantes/uso terapêutico , Ribavirina/uso terapêutico
17.
Panminerva Med ; 54(1): 1-9, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22278112

RESUMO

Hepatitis C virus (HCV) is the most common infectious cause of chronic liver disease in Europe. With the introduction of interferon based therapy in combination with ribavirin treatment of chronic HCV has become feasible. This therapy has become the standard of care for patients with HCV and depending on the HCV genotype treatment is successful in 40-70% of patients. In the recent years a new class of drugs have emerged that changed the landscape of HCV treatment. These direct antiviral agents inhibit the NS3/N4A serine protease of HCV. Prototypes are telaprevir and boceprevir and they specifically exert antiviral activity against genotype 1 HCV. A series of landmark trials has paved the way for introduction of these agents, and they have documented a great improvement in the care of genotype 1 HCV patients. Telaprevir and boceprevir are given in combination with pegylated interferon and ribavirin and are useful for treatment naive as well as treatment experienced patients. The clinician should be aware of these developments as they have implications for side effect management, and drug-drug interactions. Finally, strategic use of these agents comes with stopping rules and require close monitoring of the HCV viral load.


Assuntos
Antivirais/uso terapêutico , Hepatite C/tratamento farmacológico , Antivirais/efeitos adversos , Quimioterapia Combinada , Hepatite C/diagnóstico , Hepatite C/epidemiologia , Humanos , Seleção de Pacientes , Guias de Prática Clínica como Assunto , Medição de Risco , Fatores de Risco , Resultado do Tratamento , Carga Viral
18.
J Thromb Haemost ; 9(9): 1835-46, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21696539

RESUMO

BACKGROUND AND OBJECTIVE: Platelets abundantly express glycoprotein CD36 with thrombospondin-1 (TSP1) and oxidized low-density lipoprotein (oxLDL) as proposed ligands. How these agents promote platelet activation is still poorly understood. METHODS AND RESULTS: Both TSP1 and oxLDL caused limited activation of platelets in suspension. However, immobilized TSP1 and oxLDL, but not LDL, strongly supported platelet adhesion and spreading with a major role of CD36. Platelet spreading was accompanied by potent Ca(2+) rises, and resulted in exposure of P-selectin and integrin activation, all in a CD36-dependent manner with additional contributions of α(IIb) ß(3) and ADP receptor stimulation. Signaling responses via CD36 involved activation of the protein tyrosine kinase Syk. In whole blood perfusion, co-coating of TSP1 or oxLDL with collagen enhanced thrombus formation at high-shear flow conditions, with increased expression on platelets of activated α(IIb) ß(3), P-selectin and phosphatidylserine, again in a CD36-dependent way. CONCLUSIONS: Immobilized TSP1 and oxLDL activate platelets partly via CD36 through a Syk kinase-dependent Ca(2+) signaling mechanism, which enhances collagen-dependent thrombus formation under flow. These findings provide novel insight into the role of CD36 in hemostasis.


Assuntos
Antígenos CD36/sangue , Lipoproteínas LDL/sangue , Ativação Plaquetária/fisiologia , Trombose/sangue , Trombose/imunologia , Trombospondina 1/sangue , Sinalização do Cálcio , Movimento Celular , Colágeno/farmacologia , Humanos , Proteínas Imobilizadas , Técnicas In Vitro , Microscopia de Vídeo , Modelos Biológicos , Ativação Plaquetária/efeitos dos fármacos , Adesividade Plaquetária , Transdução de Sinais , Trombose/etiologia
19.
Aliment Pharmacol Ther ; 34(3): 335-43, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21668459

RESUMO

BACKGROUND: Treatment failure occurs in 20% of autoimmune hepatitis patients on prednisolone and azathioprine (AZA). There is no established second line treatment. AIM: To assess the efficacy of mycophenolate mofetil as second line treatment after AZA-intolerance or AZA-nonresponse in autoimmune hepatitis and overlap syndromes. METHODS: Consecutive patients from the Dutch Autoimmune Hepatitis Group cohort, consisting of 661 patients, with autoimmune hepatitis or overlap syndromes, AZA-intolerance or AZA-nonresponse and past or present use of mycophenolate mofetil were included. Primary endpoint of mycophenolate mofetil treatment was biochemical remission. Secondary endpoints were biochemical response (without remission), treatment failure and prevention of disease progression. RESULTS: Forty-five patients treated with mycophenolate mofetil were included. In autoimmune hepatitis remission or response was achieved in 13% and 27% in the AZA-nonresponse group compared to 67% and 0% in the AZA-intolerance group (P = 0.008). In overlap-syndromes remission or response was reached in 57% and 14% in the AZA-nonresponse group and 63% and 25% of the AZA-intolerance group (N.S.); 33% had side effects and 13% discontinued mycophenolate mofetil. Overall 38% had treatment failure; this was 60% in the autoimmune hepatitis AZA-nonresponse group. Decompensated liver cirrhosis, liver transplantations and death were only seen in the autoimmune hepatitis AZA-nonresponse group (P < 0.001). CONCLUSIONS: Mycophenolate mofetil induced response or remission in a majority of patients with autoimmune hepatitis and azathioprine-intolerance and with overlap syndromes, irrespective of intolerance or nonresponse for azathioprine. In autoimmune hepatitis with azathioprine nonresponse mycophenolate mofetil is less often effective.


Assuntos
Hepatite Autoimune/tratamento farmacológico , Imunossupressores/uso terapêutico , Ácido Micofenólico/análogos & derivados , Adolescente , Adulto , Idoso , Criança , Estudos de Coortes , Feminino , Hepatite Autoimune/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Ácido Micofenólico/uso terapêutico , Países Baixos , Estudos Retrospectivos , Índice de Gravidade de Doença , Síndrome , Resultado do Tratamento , Adulto Jovem
20.
Neth J Med ; 67(5): 177-81, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19581667

RESUMO

BACKGROUND: Recently, the Dutch Association of Gastroenterology and Hepatology issued new guidelines for the treatment of chronic hepatitis C virus (HCV). These guidelines reflect the current standard of care. Before these guidelines were published and implemented we (1) studied the current clinical care of HCV patients among Dutch physicians, and (2) identified areas for future refinement in the current treatment. METHODS: We conducted a non-targeted survey among Dutch medical specialists in Gastroenterology, Hepatology and Internal Medicine who actively treat HCV patients. The questionnaire contained items about facility, duration and dosing of treatment, and side effect management using clinical vignettes followed by short questions. RESULTS: We received 49 questionnaires from treating HCV specialists. The majority (65%) of respondents treat HCV patients during regular outpatient clinics, while 35% treat these patients in a separate setting dedicated to the care of HCV patients. The majority of physicians follow the stipulated dosage regimens of pegylated interferon (88%) and ribavirin (83%). A minority (13%) exceed the advised dosage of ribavirin. Side effects such as neutropenia are mostly managed by decreasing the interferon dosage (42%). Some 35% of physicians reduce ribavirin if haemoglobin levels drop below 5.4 mmol/l, and 41% initiate erythropoietin treatment. CONCLUSION: Dutch clinical practice reflects the recently issued HCV guidelines. An important area of refinement in treatment of HCV is the management of side effects.


Assuntos
Fidelidade a Diretrizes , Hepatite C/terapia , Guias de Prática Clínica como Assunto , Padrões de Prática Médica , Antivirais/administração & dosagem , Genótipo , Fidelidade a Diretrizes/estatística & dados numéricos , Hepacivirus/genética , Humanos , Países Baixos , Padrões de Prática Médica/estatística & dados numéricos , Ribavirina/administração & dosagem , Sociedades Médicas , Inquéritos e Questionários , Carga Viral
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