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1.
Remote Sens Environ ; 125: 147-156, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23049143

RESUMO

Environmental variability has important influences on mosquito life cycles and understanding the spatial and temporal patterns of mosquito populations is critical for mosquito control and vector-borne disease prevention. Meteorological data used for model-based predictions of mosquito abundance and life cycle dynamics are typically acquired from ground-based weather stations; however, data availability and completeness are often limited by sparse networks and resource availability. In contrast, environmental measurements from satellite remote sensing are more spatially continuous and can be retrieved automatically. This study compared environmental measurements from the NASA Advanced Microwave Scanning Radiometer on EOS (AMSR-E) and in situ weather station data to examine their ability to predict the abundance of two important mosquito species (Aedes vexans and Culex tarsalis) in Sioux Falls, South Dakota, USA from 2005 to 2010. The AMSR-E land parameters included daily surface water inundation fraction, surface air temperature, soil moisture, and microwave vegetation opacity. The AMSR-E derived models had better fits and higher forecasting accuracy than models based on weather station data despite the relatively coarse (25-km) spatial resolution of the satellite data. In the AMSR-E models, air temperature and surface water fraction were the best predictors of Aedes vexans, whereas air temperature and vegetation opacity were the best predictors of Cx. tarsalis abundance. The models were used to extrapolate spatial, seasonal, and interannual patterns of climatic suitability for mosquitoes across eastern South Dakota. Our findings demonstrate that environmental metrics derived from satellite passive microwave radiometry are suitable for predicting mosquito population dynamics and can potentially improve the effectiveness of mosquito-borne disease early warning systems.

2.
Vet Parasitol Reg Stud Reports ; 34: 100761, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36041796

RESUMO

Trichostrongylid nematodes can cause serious loss in the livestock economy; nevertheless, infections with these ubiquitous nematodes in animals from developing countries are largely neglected. The present paper provides a systematic review and meta-analysis to evaluate the status of trichostrongyle infections in domestic ruminants from Egypt. Out of 626 collected publications, 118 were defined suitable for inclusion in this review and represented trichostrongyle infections in 5 ruminant species (sheep, goats, cattle, buffaloes and camels) from Egypt. Published surveys have mostly focused on sheep, which had the highest (44.8%) pooled prevalence of trichostrongyle infections based on 95% confidence interval (35.9-53.6%) with no significant variations among sheep in different Egyptian regions. Goats had lower infection prevalence (31.2%, 21.5-40.8%) in comparison to sheep, and no significant regional differences were also found. The management and marketing practices likely account for the wide distribution of infection among small ruminants across Egypt. Variable trichostrongyle infection rates were estimated for camels (38.8%, 28.9-48.7%), cattle (27.4%, 14.4-40.3%) and buffaloes (12.2%, 8.0-16.4%). The prevalence of infection was significantly high during winter (52.1%, 32.2-72.1%), which provide favorable conditions for development and survival of larvae on pastures. The most common trichostrongyle identified in infected animals was Haemonchus contortus. The parasite was detected in 38.8% (29.9-47.6%) of infected sheep, 35.3% (24.8-45.7%) of infected goats and in 40.6% (18.6-62.5%) of infected camels. Clinical infections have been reported in a limited number of studies. Analysis of fecal egg counts (FECs) revealed that more than half (52.7%, 30.4-75.0%) of the tested sheep had low counts (<500 eggs per gram EPG), whereas only a few sheep (6.1%, 3.5-8.7%) had high counts >2000 EPG, implying that subclinical infections are common; however, the clinical infections cannot be completely ruled out. Anthelmintic resistance does not appear to be serious in trichostrongyle populations infecting ruminants from Egypt; nonetheless there have been a few cases of albendazole resistance in trichostrongyles infecting sheep. This paper contributes to a better understanding of the epidemiology and economic implications of trichostrongyle infections in ruminants from Egypt, which is crucial for establishing effective control strategies against these ubiquitous nematodes.


Assuntos
Bison , Doenças dos Bovinos , Doenças das Cabras , Nematoides , Doenças dos Ovinos , Animais , Búfalos , Camelus , Bovinos , Doenças dos Bovinos/epidemiologia , Egito/epidemiologia , Doenças das Cabras/epidemiologia , Doenças das Cabras/parasitologia , Cabras , Ovinos , Doenças dos Ovinos/epidemiologia , Doenças dos Ovinos/parasitologia
3.
Environ Health Perspect ; 130(8): 87006, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35972761

RESUMO

BACKGROUND: West Nile virus (WNV), a global arbovirus, is the most prevalent mosquito-transmitted infection in the United States. Forecasts of WNV risk during the upcoming transmission season could provide the basis for targeted mosquito control and disease prevention efforts. We developed the Arbovirus Mapping and Prediction (ArboMAP) WNV forecasting system and used it in South Dakota from 2016 to 2019. This study reports a post hoc forecast validation and model comparison. OBJECTIVES: Our objective was to validate historical predictions of WNV cases with independent data that were not used for model calibration. We tested the hypothesis that predictive models based on mosquito surveillance data combined with meteorological variables were more accurate than models based on mosquito or meteorological data alone. METHODS: The ArboMAP system incorporated models that predicted the weekly probability of observing one or more human WNV cases in each county. We compared alternative models with different predictors including a) a baseline model based only on historical WNV cases, b) mosquito models based on seasonal patterns of infection rates, c) environmental models based on lagged meteorological variables, including temperature and vapor pressure deficit, d) combined models with mosquito infection rates and lagged meteorological variables, and e) ensembles of two or more combined models. During the WNV season, models were calibrated using data from previous years and weekly predictions were made using data from the current year. Forecasts were compared with observed cases to calculate the area under the receiver operating characteristic curve (AUC) and other metrics of spatial and temporal prediction error. RESULTS: Mosquito and environmental models outperformed the baseline model that included county-level averages and seasonal trends of WNV cases. Combined models were more accurate than models based only on meteorological or mosquito infection variables. The most accurate model was a simple ensemble mean of the two best combined models. Forecast accuracy increased rapidly from early June through early July and was stable thereafter, with a maximum AUC of 0.85. The model predictions captured the seasonal pattern of WNV as well as year-to-year variation in case numbers and the geographic pattern of cases. DISCUSSION: The predictions reached maximum accuracy early enough in the WNV season to allow public health responses before the peak of human cases in August. This early warning is necessary because other indicators of WNV risk, including early reports of human cases and mosquito abundance, are poor predictors of case numbers later in the season. https://doi.org/10.1289/EHP10287.


Assuntos
Conceitos Meteorológicos , Febre do Nilo Ocidental , Previsões , Humanos , América do Norte/epidemiologia , Vigilância em Saúde Pública , Estações do Ano , Estados Unidos/epidemiologia , Febre do Nilo Ocidental/epidemiologia , Vírus do Nilo Ocidental
4.
BMC Cancer ; 11: 456, 2011 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-22014088

RESUMO

BACKGROUND: Magnolol, a plant lignan isolated from the bark and seed cones of Magnolia officinalis, has been shown to have chemopreventive effects on chemically-induced skin cancer development. The objectives of this investigation are to study the anticarcinogenic effects of magnolol on UVB-induced skin tumor development in SKH-1 mice, a model relevant to humans, and determine the possible role of apoptosis and cell cycle arrest involved in the skin tumor development. METHODS: UVB-induced skin carcinogenesis model in SKH-1 mice was used for determining the preventive effects of magnolol on skin cancer development. Western blottings and flow cytometric analysis were used to study the effects of magnolol on apoptosis and cell cycle. RESULTS: Magnolol pretreated groups (30, 60 µ g) before UVB treatments (30 mJ/cm2, 5 days/week) resulted in 27-55% reduction in tumor multiplicity as compared to control group in SKH-1 mice. Magnolol pretreatment increased the cleavage of caspase-8 and poly-(-ADP-ribose) polymerase (PARP), increased the expression of p21, a cell cycle inhibitor, and decreased the expression of proteins involved in the G2/M phase of cell cycle in skin samples from SKH-1 mice.Treatment of A431 cells with magnolol decreased cell viability and cell proliferation in a concentration dependent manner. Magnolol induced G2/M phase cell cycle arrest in A431 cells at 12 h with a decreased expression of cell cycle proteins such as cyclin B1, cyclin A, CDK4, Cdc2 and simultaneous increase in the expression of Cip/p21, a cyclin-dependent kinase inhibitor. Magnolol induced apoptosis in vivo and in vitro with an increased cleavage of caspase-8 and PARP. Phospho-signal transducers and activators of transcription 3 (Tyr705), B-Raf, p-MEK, and p-AKT were down-regulated, whereas phosphorylation of ERK was induced by magnolol in A431 cells. CONCLUSIONS: Magnolol pretreatments prevent UVB-induced skin cancer development by enhancing apoptosis, causing cell cycle arrest at G2/M phase, and affecting various signaling pathways. Magnolol could be a potentially safe and potent anticarcinogenic agent against skin cancer.


Assuntos
Anticarcinógenos/farmacologia , Compostos de Bifenilo/farmacologia , Carcinoma de Células Escamosas/tratamento farmacológico , Lignanas/farmacologia , Neoplasias Induzidas por Radiação/tratamento farmacológico , Neoplasias Cutâneas/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Western Blotting , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/prevenção & controle , Caspases/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Quinases Ciclina-Dependentes/metabolismo , Ciclinas/metabolismo , Citometria de Fluxo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Camundongos , Neoplasias Induzidas por Radiação/patologia , Neoplasias Induzidas por Radiação/prevenção & controle , Fosforilação/efeitos dos fármacos , Fator de Transcrição STAT3/metabolismo , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/prevenção & controle , Raios Ultravioleta
5.
J Med Entomol ; 48(3): 669-79, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21661329

RESUMO

This study compared the spatial and temporal patterns of Culex tarsalis Coquillett and Aedes vexans Meigen populations and examined their relationships with land cover types and climatic variability in Sioux Falls, SD. Between 24 and 30 CDC CO2-baited light traps were set annually in Sioux Falls from May to September 2005-2008. Land cover data were acquired from the 2001 National Land Cover Dataset and the percentages of selected land cover types were calculated within a 600-m buffer zone around each trap. Meteorological information was summarized from local weather stations. Cx. tarsalis exhibited stronger spatial autocorrelation than Ae. vexans. Land cover analysis indicated that Cx. tarsalis was positively correlated with grass/hay, and Ae. vexans was positively correlated with wetlands. No associations were identified between irrigation and the host-seeking population of each species. Higher temperature in the current week and 2 wk prior and higher precipitation 3-4 wk before collection of host-seeking adult mosquitoes had positive influences on Cx. tarsalis abundance. Temperature in the current week and rainfall 2-3 wk before sampling had positive influences on Ae. vexans abundance. This study revealed the different influences of weather and land cover on important mosquito species in the Northern Great Plains region, which can be used to improve local vector control strategies and West Nile virus prevention efforts.


Assuntos
Aedes/fisiologia , Culex/fisiologia , Animais , Ecossistema , Feminino , Insetos Vetores/fisiologia , Densidade Demográfica , South Dakota , Tempo (Meteorologia) , Febre do Nilo Ocidental/prevenção & controle , Vírus do Nilo Ocidental/fisiologia
6.
Vet Parasitol ; 293: 109418, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33866048

RESUMO

Trichostrongyle nematodes can be a major threat to the profitability of small ruminant producers depending of the species and intensity of trichostrongyles parasitizing their herd. Haemonchus contortus, Teladorsagia circumcincta, and Trichostrongylus colubriformis are typically the most common and clinically important species. Three lectins (PNA, LCA and AAL) have been reported to bind specifically to eggs from these three genera and therefore could be used to quantify the intensity of each species in individual animals. Peanut agglutinin (PNA) has been the most commonly tested lectin because it selectively binds intensely to eggs of the most pathogenic species, H. contortus. Lens culinaris agglutinin (LCA) and Aleuria aurantia agglutinin (AAL) have shown specificity to T. circumcincta and Trichostrongylus spp. respectively, however, these lectins have only been evaluated using eggs harvested directly from adult females, and not from fecal samples. The purpose of the present study is to describe a method to sequentially stain H. contortus, T. circumcincta and Trichostrongylus spp. fecal eggs with PNA, LCA and AAL, and then evaluate the resultant staining patterns seen with eggs collected from a naturally infected goat shown with PCR to contain H. contortus, T. circumcincta, Ostertagia leptospicularis, Trichostrongylus colubriformis and Trichostrongylus axei eggs. These results were also compared with patterns observed with eggs stained with single lectins and double combinations of lectins. The various patterns were then compared to those seen with egg samples collected from an ewe shown to only contain H. contortus. PNA bound intensely and uniformly to all eggs from samples containing only H. contortus eggs; however, some eggs additionally bound LCA and AAL in localized patches of varying size, and a few eggs exhibited intense and uniform binding of all three lectins. Single PNA-staining of goat samples containing the five trichostrongyles species identified most eggs as H. contortus, and triple-staining showed patterns consistent with those seen for H. contortus. Binding of AAL to non-Haemonchus eggs was uniform but showed significant variations in intensity. Lesser staining eggs tended to also stain intensely with LCA, which is consistent with published binding pattern for T. circumcincta. Most eggs that AAL bound intensely to did not bind with LCA, which is consistent with published binding pattern for Trichostrongylus spp. Autofluorescence was observed with the DAPI filter-cube among most non-Haemonchus eggs. This study demonstrates the need for additional field studies to further validate the specificity of these three lectins for use in identifying eggs from the three species of trichostrongyles.


Assuntos
Doenças das Cabras , Lectinas , Infecções por Nematoides , Coloração e Rotulagem , Animais , Ascomicetos , Doenças das Cabras/diagnóstico , Doenças das Cabras/parasitologia , Cabras , Haemonchus , Lectinas/metabolismo , Infecções por Nematoides/diagnóstico , Infecções por Nematoides/parasitologia , Infecções por Nematoides/veterinária , Óvulo , Coloração e Rotulagem/veterinária
7.
Vet Clin North Am Food Anim Pract ; 36(1): 59-71, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32029189

RESUMO

Parasite species infecting cattle throughout northern North American are generally the same as those found throughout North America. Throughout Canada, cattle are primarily infected with Ostertagia ostertagi and Cooperia oncophora, whose larvae survive cold winters within soil of pastures. Overwintering larvae of these species maintain a temporary population of refugia available in spring to grazing cattle. Cattle from northern United States are also infected with Cooperia punctata and Haemonchus placei, whose larvae cannot survive cold winters within pastures. Anthelmintics with persistent activity are used during spring to recover some of these losses; however, anthelmintic resistance limits effectiveness of this strategy.


Assuntos
Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/prevenção & controle , Infecções por Nematoides/veterinária , Animais , Anti-Helmínticos/administração & dosagem , Bovinos , Doenças dos Bovinos/tratamento farmacológico , Doenças dos Bovinos/parasitologia , Indústria de Laticínios/métodos , Feminino , Trato Gastrointestinal/parasitologia , Nematoides/isolamento & purificação , Infecções por Nematoides/tratamento farmacológico , Infecções por Nematoides/epidemiologia , Infecções por Nematoides/prevenção & controle , América do Norte/epidemiologia , Estações do Ano
8.
J Med Entomol ; 57(3): 862-871, 2020 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-31799615

RESUMO

Mosquito surveillance has been conducted across South Dakota (SD) to record and track potential West Nile virus (WNV) vectors since 2004. During this time, communities from 29 counties collected nearly 5.5 million mosquitoes, providing data from over 60,000 unique trapping nights. The nuisance mosquito, Aedes vexans (Meigen) was the most abundant species in the state (39.9%), and most abundant in most regions. The WNV vector, Culex tarsalis Coquillett (Diptera: Culicidae), was the second most abundant species (20.5%), and 26 times more abundant than the other Culex species that also transmit WNV. However, geographic variation did exist between WNV vector species, as well as relative abundance of vector and nuisance mosquitoes. The abundance of Ae. vexans decreased from east to west in South Dakota, resulting in an increase in the relative abundance of Cx. tarsalis. Other species are reported in this study, with various relative abundances throughout the different regions of South Dakota. WNV infection rates of mosquitoes showed that Cx. tarsalis had the most positive sampling pools and the highest vector index of all the species tested. This study addressed the need for an updated summary of the predominant mosquito species present in the United States Northern Great Plain and provides infection rate data for WNV among these predominant species.


Assuntos
Aedes/virologia , Culex/virologia , Mosquitos Vetores/virologia , Vírus do Nilo Ocidental/isolamento & purificação , Animais , Feminino , Dinâmica Populacional , South Dakota
9.
Mar Drugs ; 7(2): 153-65, 2009 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-19597578

RESUMO

Sarcophine-diol (SD), one of the structural modifications of sarcophine, has shown chemopreventive effects on 12-dimethylbenz(a)anthracene-initiated and 12-O-tetradecanoylphorbol-13-acetate-promoted skin tumor development in female CD-1 mice. The objective of this study was to determine the chemopreventive effects of SD on UVB-induced skin tumor development in hairless SKH-1 mice, a model more relevant to human skin cancer, and to determine the possible mechanisms of action. Carcinogenesis was initiated and promoted by UVB radiation. Female hairless SKH-1 mice were divided into two groups having 27 mice in each group: control and SD treatment. The control group was topically treated with 100 microL acetone and SD treatment group was topically treated with SD (30 microg/100 microL in acetone) 1 hour before each UVB radiation for 32 weeks. Tumor counts were recorded on a weekly basis for 30 weeks. Effects of SD on the expression of caspases were investigated to elucidate the possible mechanism of action. The proteins from epidermal homogenates of experimental mice were used for SDS-PAGE and Western blotting using specific antibodies against caspase-3, caspase-8 and caspase-9 respectively. TUNEL assay was used for determining DNA fragmented apoptotic cells in situ. Results showed that at the end of experiment, tumor multiplicity in control and SD treatment groups was 25.8 and 16.5 tumors per mouse respectively. Furthermore, Topical treatment of SD induced DNA fragmented apoptotic cells by upgrading the expressions of cleaved caspase-3 and caspase-8. This study clearly suggested that SD could be an effective chemopreventive agent for UVB-induced skin cancer by inducing caspase dependent apoptosis.


Assuntos
4-Butirolactona/análogos & derivados , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma de Células Escamosas/prevenção & controle , Neoplasias Induzidas por Radiação/prevenção & controle , Neoplasias Cutâneas/prevenção & controle , Raios Ultravioleta , 4-Butirolactona/farmacologia , Animais , Peso Corporal/efeitos dos fármacos , Carcinoma de Células Escamosas/patologia , Caspase 3/metabolismo , Caspase 8/metabolismo , Fragmentação do DNA/efeitos dos fármacos , Feminino , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Camundongos , Camundongos Pelados , Modelos Animais , Neoplasias Cutâneas/patologia
10.
Cytotechnology ; 71(1): 127-148, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30600465

RESUMO

The intestinal epithelium is a major site of interaction with pathogens. In bovine intestinal epithelial cells (BIECs), Toll-like receptors (TLRs) play an important role in innate immune responses against enteric pathogens. This study is aimed at establishing a stable bovine intestinal epithelial cell line that can be maintained by a continuous passage so that studies on innate immune responses against various enteric pathogens can be performed. The main goal was to establish pure cultures of primary and immortalized bovine intestinal epithelial cells from the ileum and then characterize them biochemically and immunologically. Mixed epithelial and fibroblast bovine ileal intestinal cultures were first established from a 2-day old calf. Limiting dilution method was used to obtain a clone of epithelial cells which was characterized using immunocytochemistry (ICC). The selected clone BIEC-c4 was cytokeratin positive and expressed low levels of vimentin, confirming the epithelial cell phenotype. Early passage BIEC-c4 cells were transfected with either simian virus 40 (SV40) large T antigen or human telomerase reverse transcriptase (hTERT), or human papillomavirus (HPV) type 16E6/E7 genes to establish three immortalized BIEC cell lines. The expression of SV40, hTERT and HPV E6/E7 genes in immortalized BIECs was confirmed by a polymerase chain reaction (PCR). Immunocytochemistry and immunofluorescence assays also confirmed the expression of SV40, hTERT and HPV E6 proteins. The immortalized BIECs were cytokeratin positive and all except HPV-BIECs expressed low levels of vimentin. A growth kinetics study indicated that there were no significant differences in the doubling time of immortalized BIECs as compared to early passage BIEC-c4 cells. All four BIEC types expressed TLR 1-10 genes, with TLR 3 and 4 showing higher expression across all cell types. These newly established early passage and immortalized BIEC cell lines should serve as a good model for studying infectivity, pathogenesis and innate immune responses against enteric pathogens.

11.
J Parasitol ; 105(4): 484-490, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31268411

RESUMO

Trichostrongylid nematodes are a common cause of gastroenteritis in sheep. Despite its worldwide distribution, Teladorsagia circumcincta has not been included in reports listing the various trichostrongyles infecting sheep from Egypt. Herein, we describe the presence of 2 T. circumcincta haplotypes infecting small ruminants from Egypt. For this study, fresh fecal samples were collected from 340 sheep and 115 goats reared at 5 districts in Dakahlia governorate and its surroundings, Egypt. Trichostrongyle eggs were harvested from the samples, and then subjected to DNA isolation and analysis. Polymerase chain reaction (PCR) amplification was carried out for the second internal transcribed spacer of ribosomal DNA (ITS2 rDNA). Purified PCR products of T. circumcincta were sequenced, and the revealed sequences were subjected to the nucleotide and phylogenetic analysis. A relatively high prevalence of trichostrongyles eggs was identified in sheep (33.2%) and a lower prevalence was found in goats (14.7%). Molecular analysis revealed, for the first time, 2 sheep herds from Egypt that were infected with T. circumcincta. Both infected herds were raised by the Bedouins in rural areas of El Mahalla El Kubra city. No T. circumcincta infections were found in any of the goats. Nucleotide sequence analysis revealed 2 haplotypes (Te1 and Te2) from 7 successfully sequenced samples (5 from the first and 2 from the second herd). Te1 was the major haplotype in both herds, and Te2 was retrieved from a single sample. Phylogenetic analysis displayed that the Te1 haplotype clustered with one from Cyprus, which might have been introduced to Egypt via goats imported from Cyprus due to a program to improve meat and milk production in Egypt. The present results could be beneficial in understanding the epidemiology of T. circumcincta and other trichostrongyles in Egypt, and have implementations in the effective control strategies used in this region.


Assuntos
Gastroenterite/veterinária , Doenças dos Ovinos/parasitologia , Trichostrongyloidea/isolamento & purificação , Tricostrongiloidíase/veterinária , Animais , DNA de Helmintos/análise , DNA de Helmintos/isolamento & purificação , DNA Espaçador Ribossômico/química , Egito/epidemiologia , Fezes/parasitologia , Gastroenterite/epidemiologia , Gastroenterite/parasitologia , Doenças das Cabras/epidemiologia , Doenças das Cabras/parasitologia , Cabras , Haplótipos , Filogenia , Reação em Cadeia da Polimerase/veterinária , Prevalência , População Rural , Alinhamento de Sequência/veterinária , Análise de Sequência de DNA/veterinária , Ovinos , Doenças dos Ovinos/epidemiologia , Trichostrongyloidea/genética , Tricostrongiloidíase/epidemiologia , Tricostrongiloidíase/parasitologia
12.
In Vitro Cell Dev Biol Anim ; 55(7): 533-547, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31183683

RESUMO

Intestinal sub-epithelial myofibroblasts (ISEMFs) are mesenchymal cells that do not express cytokeratin but express α-smooth muscle actin and vimentin. Despite being cells with diverse functions, there is a paucity of knowledge about their origin and functions primarily due to the absence of a stable cell line. Although myofibroblast in vitro models for human, mouse, and pig are available, there is no ISEMF cell line available from young calves. We isolated and developed an ileal ISEMF cell line from a 2-d-old calf that expressed α-smooth muscle actin and vimentin but no cytokeratin indicating true myofibroblast cells. To overcome replicative senescence, we immortalized primary cells with SV40 large T antigen. We characterized and compared both primary and immortalized ileal ISEMF cells for surface glycan and Toll-like-receptor (TLR) expression by lectin-binding assay and real-time quantitative PCR (RT-qPCR) assay respectively. SV40 immortalization significantly decreased surface lectin binding for lectins GSL-I, PHA-L, ECL, Jacalin, Con-A, LCA, and LEL. Both cell types expressed TLRs 1-9 and showed no significant differences in TLR expression. Thus, these cells can be useful in vitro model to study ISEMF's origin, physiology, and functions.


Assuntos
Técnicas de Cultura de Células/métodos , Íleo/citologia , Mucosa Intestinal/citologia , Miofibroblastos/citologia , Actinas/biossíntese , Animais , Antígenos Transformantes de Poliomavirus/genética , Antígenos Virais de Tumores/genética , Bovinos , Linhagem Celular Transformada , Queratinas/biossíntese , Receptores Toll-Like/biossíntese , Vimentina/biossíntese
13.
Virology ; 528: 152-163, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30616205

RESUMO

Influenza viruses are a group of respiratory pathogens that have evolved into four different types: A, B, C, and D. A common feature is that all four types are capable of replicating and transmitting among pigs. Here, we describe the development of isogenous cell culture system from the swine respiratory tract to study influenza viruses. Phenotypic characterization of swine primary nasal turbinate, trachea and lung cells revealed high expression of cytokeratin and demonstrated tissue site dependent expression of tight junction proteins. Furthermore, lectin binding assay on these cells demonstrated higher levels of Sia2-6Gal than Sia2-3Gal receptors and supported the replication of influenza A, B, C, and D viruses to appreciable levels at both 33 and 37 °C, but replication competence was dependent on virus type or temperature used. Overall, these swine primary respiratory cells showed epithelial phenotype, which is suitable for studying the comparative biology and pathobiology of influenza viruses.


Assuntos
Células Epiteliais/virologia , Pulmão/citologia , Orthomyxoviridae/fisiologia , Traqueia/citologia , Animais , Técnicas de Cultura de Células , Queratinas/genética , Pulmão/virologia , Fenótipo , Suínos , Proteínas de Junções Íntimas/genética , Traqueia/virologia , Replicação Viral
14.
Int J Pharm ; 350(1-2): 113-21, 2008 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-17913410

RESUMO

Aim of this study was to prepare polyamine-conjugated PAMAM dendrimers and study their permeability across Caco-2 cell monolayers. Polyamines, namely, arginine and ornithine were conjugated to the amine terminals of the G4 PAMAM dendrimers by Fmoc synthesis. The apical-to-basolateral (AB) and basolateral-to-apical (BA) apparent permeability coefficients (P(app)) for the PAMAM dendrimers increased by conjugating the dendrimers with both of the polyamines. The enhancement in permeability was dependent on the dendrimer concentration and duration of incubation. The correlation between monolayer permeability and the decrease in transepithelial electrical resistance (TEER) with both the PAMAM dendrimers and the polyamine-conjugated dendrimers suggests that paracellular transport is one of the mechanisms of transport across the epithelial cells. Cytotoxicity of the polyamine-conjugated dendrimers was evaluated in Caco-2 cells by MTT (methylthiazoletetrazolium) assay. Arginine-conjugated dendrimers were slightly more toxic than PAMAM dendrimer as well as ornithine-conjugated dendrimers. Though investigations on the possible involvement of other transport mechanisms are in progress, results of the present study suggest the potential of dendrimer-polyamine conjugates as drug carriers to increase the oral absorption of drugs.


Assuntos
Epitélio/metabolismo , Poliaminas/farmacocinética , Células CACO-2 , Sobrevivência Celular/efeitos dos fármacos , Dendrímeros , Impedância Elétrica , Humanos , Permeabilidade , Poliaminas/farmacologia
15.
Acta Trop ; 185: 242-250, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29727611

RESUMO

Models that forecast the timing and location of human arboviral disease have the potential to make mosquito control and disease prevention more effective. A common approach is to use statistical time-series models that predict disease cases as lagged functions of environmental variables. However, the simplifying assumptions required for standard modeling approaches may not capture important aspects of complex, non-linear transmission cycles. Here, we compared a set of alternative models of human West Nile virus (WNV) in 2004-2017 in South Dakota, USA. We used county-level logistic regressions to model historical human case data as functions of distributed lag summaries of air temperature and several moisture indices. We tested two variations of the standard model in which 1) the distributed lag functions were allowed to change over the transmission season, so that dependence on past meteorological conditions was time varying rather than static, and 2) an additional predictor was included that quantified the mosquito infection growth rate estimated from mosquito surveillance data. The best-fitting model included temperature and vapor pressure deficit as meteorological predictors, and also incorporated time-varying lags and the mosquito infection growth rate. The time-varying lags helped to predict the seasonal pattern of WNV cases, whereas the mosquito infection growth rate improved the prediction of year-to-year variability in WNV risk. These relatively simple and practical enhancements may be particularly helpful for developing data-driven time series models for use in arbovirus forecasting applications.


Assuntos
Surtos de Doenças , Modelos Estatísticos , Temperatura , Pressão de Vapor , Febre do Nilo Ocidental/epidemiologia , Animais , Doenças Endêmicas , Humanos , Mosquitos Vetores , South Dakota/epidemiologia , Vírus do Nilo Ocidental
16.
Biomed Res Int ; 2018: 2014764, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30112366

RESUMO

In 2016, we compared susceptibility to the insecticide, permethrin, between the West Nile virus vector, Culex tarsalis Coquillett, and a major nuisance mosquito, Aedes vexans (Meigen), using baseline diagnostic dose and time values determined using the CDC bottle bioassay protocol. Mosquitoes were collected in the wild in Brookings County, South Dakota, situated in the Northern Great Plains of the USA. The determined diagnostic dose and time were then used in 2017 to validate these measurements for the same 2 mosquito species, collected at a second location within Brookings County. The diagnostic dose was determined for multiple time periods and ranged from 27.0 µg/ml at 60 min to 38.4 µg/ml at 30 min. There was no significant difference detected in mortality rates between Cx. tarsalis and Ae. vexans for any diagnostic time and dose. For practical purposes, mosquitoes in 2017 were tested at 38 µg/ml for 30 min; expected mortality rates were 93.38% for Cx. tarsalis and 94.93% for Ae. vexans. Actual 2017 mortality rates were 92.68% for Cx. tarsalis and 96.12% for Ae. vexans, validating the usefulness of this baseline at an additional location and year.


Assuntos
Culex/efeitos dos fármacos , Inseticidas/farmacologia , Mosquitos Vetores , Permetrina/farmacologia , Aedes , Animais , Culex/virologia , Insetos Vetores , Febre do Nilo Ocidental/prevenção & controle , Vírus do Nilo Ocidental
17.
Vet Parasitol ; 145(3-4): 361-5, 2007 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-17289268

RESUMO

Despite the development of several recent PCR assays for the egg stages of various trichostrongyles, there have been no protocols described for preserving field samples for PCR without refrigeration. In this study, Lugol's iodine (LI), sodium azide (SA), and neutral buffered formalin (NBF) were evaluated using Haemonchus contortus eggs to determine their potential as a preservative for trichostrongyle egg samples to be processed with real-time PCR. When egg recovery, embryo development, and egg morphology were evaluated from fecal samples preserved with LI, NBF, and SA, there was equally good recovery and preservation for the first month. Preserved eggs were detectable for 1 month, but after 6 months, none could be recovered. When real-time PCR analysis was performed on eggs isolated from faeces preserved with LI and SA, there was no detectable inhibition compared to fresh, non-preserved eggs; however, NBF significantly inhibited amplification. The results from this study demonstrate that for PCR applications LI and SA are effective preservatives for H. contortus eggs, resulting in good preservation of morphology while allowing for uninhibited PCR.


Assuntos
Fixadores , Haemonchus/citologia , Haemonchus/genética , Óvulo/citologia , Óvulo/metabolismo , Reação em Cadeia da Polimerase/métodos , Preservação Biológica/métodos , Animais , Formaldeído , Iodetos , Azida Sódica
18.
PLoS Curr ; 92017 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-28736681

RESUMO

INTRODUCTION: Predicting the timing and locations of future mosquito-borne disease outbreaks has the potential to improve the targeting of mosquito control and disease prevention efforts. Here, we present and evaluate prospective forecasts made prior to and during the 2016 West Nile virus (WNV) season in South Dakota, a hotspot for human WNV transmission in the United States. METHODS: We used a county-level logistic regression model to predict the weekly probability of human WNV case occurrence as a function of temperature, precipitation, and an index of mosquito infection status. The model was specified and fitted using historical data from 2004-2015 and was applied in 2016 to make short-term forecasts of human WNV cases in the upcoming week as well as whole-year forecasts of WNV cases throughout the entire transmission season. These predictions were evaluated at the end of the 2016 WNV season by comparing them with spatial and temporal patterns of the human cases that occurred. RESULTS: There was an outbreak of WNV in 2016, with a total of 167 human cases compared to only 40 in 2015. Model results were generally accurate, with an AUC of 0.856 for short-term predictions. Early-season temperature data were sufficient to predict an earlier-than-normal start to the WNV season and an above-average number of cases, but underestimated the overall case burden. Model predictions improved throughout the season as more mosquito infection data were obtained, and by the end of July the model provided a close estimate of the overall magnitude of the outbreak. CONCLUSIONS: An integrated model that included meteorological variables as well as a mosquito infection index as predictor variables accurately predicted the resurgence of WNV in South Dakota in 2016. Key areas for future research include refining the model to improve predictive skill and developing strategies to link forecasts with specific mosquito control and disease prevention activities.

19.
Vet Parasitol ; 135(3-4): 297-302, 2006 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-16303253

RESUMO

A multiplex PCR assay for differentiating strongyle eggs from cattle has recently been described; however, the egg disruption and DNA extraction procedures, though effective, are inadequate for large studies or clinical application. The purpose of this research was to evaluate methods for disrupting trichostrongyle eggs, then assess commercial kits for extracting egg DNA using Ostertagia ostertagi as a model species. Egg disruption procedures tested included probe sonication, bath sonication, bead beating, boiling, microwaving, proteinase K/SDS digestion, freezing, and various combinations of the above with the incorporation of sodium dodecyl sulfate. These procedures were evaluated in conjunction with four commercial DNA extraction kits: DNA Stool mini kit and DNeasy Plant kit (Qiagen), Fast DNA kit (QBiogene), and the MAP extraction kit (Tetracore). Results showed that egg disruption was best accomplished with the bead beater and ceramic beads, resulting in 100% disruption within 1min. When DNA extraction was preceded by the isolation of eggs from feces, all procedures except the Fast DNA kit produced PCR-ready DNA from at least two eggs. The DNeasy Plant kit allowed consistent detection of DNA released from one egg. Due to the morphological similarities among trichostrongyle eggs in ruminants, strongyle eggs in equids, and hookworm eggs, the methods described herein may have broad application to other nematodes.


Assuntos
Doenças dos Bovinos/diagnóstico , DNA de Helmintos/isolamento & purificação , Ostertagia/isolamento & purificação , Animais , Bovinos , Doenças dos Bovinos/parasitologia , DNA de Helmintos/análise , DNA de Helmintos/química , Diagnóstico Diferencial , Fezes/parasitologia , Ostertagia/genética , Contagem de Ovos de Parasitas/veterinária , Reação em Cadeia da Polimerase/métodos , Reação em Cadeia da Polimerase/veterinária , Sensibilidade e Especificidade , Especificidade da Espécie , Trichostrongyloidea/isolamento & purificação
20.
J Histochem Cytochem ; 53(2): 197-205, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15684332

RESUMO

Galectins are an evolutionarily conserved family of 15 different lectins found in various combinations in virtually every type of animal cell. One of the primary galectins expressed in intestinal epithelium is galectin-4, a tandem-repeat galectin with two carbohydrate-recognition domains in a single polypeptide chain. In the current study, we produced an anti-galectin-4 monoclonal antibody (MAb) for determining the distribution of galectin-4 in porcine small intestine to enhance our understanding of where galectin-4 performs its functions in the small intestine. In immunohistochemistry studies, this MAb detected galectin-4 primarily in the cytoplasm of absorptive epithelial cells lining intestinal villi. Mature epithelial cells at the villous tips stained the most intensely with this MAb, with progressively less intense staining observed along the sides of villi and into the crypts. In addition to its cytoplasmic localization, galectin-4 was also associated with nuclei in villous tip cells, indicating that some galectin-4 may migrate to the nucleus during terminal maturation of these cells. In intestinal crypts, a specific subset of cells, which may be enteroendocrine cells, expressed galectin-4 at a relatively high level. Galectin-4 distribution patterns were similar in all three regions (duodenum, jejunum, and ileum) of porcine small intestine.


Assuntos
Galectina 4/metabolismo , Intestino Delgado/metabolismo , Animais , Anticorpos Monoclonais , Especificidade de Anticorpos , Citoplasma/metabolismo , Citoplasma/ultraestrutura , Duodeno/metabolismo , Duodeno/ultraestrutura , Células Enteroendócrinas/metabolismo , Células Enteroendócrinas/ultraestrutura , Células Epiteliais/metabolismo , Células Epiteliais/ultraestrutura , Galectina 4/imunologia , Galectina 4/ultraestrutura , Íleo/metabolismo , Íleo/ultraestrutura , Imuno-Histoquímica , Mucosa Intestinal/metabolismo , Mucosa Intestinal/ultraestrutura , Intestino Delgado/ultraestrutura , Jejuno/metabolismo , Jejuno/ultraestrutura , Suínos
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