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1.
Int J Hyg Environ Health ; 260: 114390, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38772087

RESUMO

OBJECTIVES: In the US, violations of drinking water regulations are highest in lower-income rural areas overall, and particularly in Central Appalachia. However, data on drinking water use, quality, and associated health outcomes in rural Appalachia are limited. We sought to assess public and private drinking water sources and associated risk factors for waterborne pathogen exposures for individuals living in rural regions of Appalachian Virginia. METHODS: We administered surveys and collected tap water, bottled water, and saliva samples in lower-income households in two adjacent rural counties in southwest Virginia (bordering Kentucky and Tennessee). Water samples were tested for pH, temperature, conductivity, total coliforms, E. coli, free chlorine, nitrate, fluoride, heavy metals, and specific pathogen targets. Saliva samples were analyzed for antibody responses to potentially waterborne infections. We also shared water analysis results with households. RESULTS: We enrolled 33 households (83 individuals), 82% (n = 27) with utility-supplied water and 18% with private wells (n = 3) or springs (n = 3). 58% (n = 19) reported household incomes of <$20,000/year. Total coliforms were detected in water samples from 33% (n = 11) of homes, E. coli in 12%, all with wells or springs (n = 4), and Aeromonas, Campylobacter, and Enterobacter in 9%, all spring water (n = 3). Diarrhea was reported for 10% of individuals (n = 8), but was not associated with E. coli detection. 34% (n = 15) of saliva samples had detectable antibody responses for Cryptosporidium spp., C. jejuni, and Hepatitis E. After controlling for covariates and clustering, individuals in households with septic systems and straight pipes had significantly higher likelihoods of antibody detection (risk ratios = 3.28, 95%CI = 1.01-10.65). CONCLUSIONS: To our knowledge, this is the first study to collect and analyze drinking water samples, saliva samples, and reported health outcome data from low-income households in Central Appalachia. Our findings indicate that utility-supplied water in this region was generally safe, and individuals in low-income households without utility-supplied water or sewerage have higher exposures to waterborne pathogens.

2.
Infect Immun ; 91(10): e0027523, 2023 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-37725059

RESUMO

Cryptosporidium species are a leading cause of pediatric diarrheal disease and death in low- and middle-income countries and pose a particular threat to immunocompromised individuals. As a zoonotic pathogen, Cryptosporidium can have devastating effects on the health of neonatal calves. Despite its impact on human and animal health, consistently effective drug treatments for cryptosporidiosis are lacking and no vaccine is available. We previously showed that C. parvum mucin-like glycoproteins, gp40, and gp900 express an epitope identified by a monoclonal antibody 4E9. 4E9 neutralized C. parvum infection in vitro as did glycan-binding proteins specific for the Tn antigen (GalNAc-α1-S/T). Here, we show that 4E9 ameliorates disease in vivo in a calf challenge model. The 4E9 epitope is present on C. hominis in addition to C. parvum gp40 and gp900 and localizes to the plasma membrane and dense granules of invasive and intracellular stages. To characterize the epitope recognized by 4E9, we probed a glycan array containing over 500 defined glycans together with a custom-made glycopeptide microarray containing glycopeptides from native mucins or C. parvum gp40 and gp15. 4E9 exhibited no binding to the glycan array but bound strongly to glycopeptides from native mucins or gp40 on the glycopeptide array, suggesting that the antibody epitope contains both peptide and glycan moieties. 4E9 only recognized glycopeptides with adjacent S or T residues in the motif S*/T*-X-S*/T* where X = 0 or 1. These data define the 4E9 epitope and have implications for the inclusion of the epitope in the development of vaccines or other immune-based therapies.


Assuntos
Criptosporidiose , Cryptosporidium parvum , Cryptosporidium , Animais , Bovinos , Humanos , Criança , Criptosporidiose/prevenção & controle , Epitopos , Glicopeptídeos/metabolismo , Anticorpos Monoclonais/metabolismo , Mucinas/metabolismo , Polissacarídeos/metabolismo
3.
Trends Parasitol ; 39(7): 499-500, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37150658

RESUMO

Invasive Cryptosporidium sporozoites contain organelles that secrete unique proteins to facilitate invasion and remodeling of the infected cell. By identifying a novel secretory organelle, 'small granules', and defining the global content of all the secretory organelles, Guérin et al. set the stage to uncover molecular determinants of virulence at the host cell interface.


Assuntos
Criptosporidiose , Cryptosporidium , Humanos , Criptosporidiose/parasitologia , Interações Hospedeiro-Parasita , Secretoma , Organelas/metabolismo , Proteínas de Protozoários/metabolismo
4.
Nutrients ; 15(5)2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36904212

RESUMO

The profile of the intestinal microbiota is known to be altered in malnourished young children in low- and middle-income countries. However, there are limited studies longitudinally evaluating the intestinal microbiota in malnourished young children in resource-limited settings over the first two years of life. In this longitudinal pilot study, we determined the effect of age, residential location, and intervention on the composition, relative abundance, and diversity of the intestinal microbiota in a representative sample of children under 24 months of age with no diarrhea in the preceding 72 h in the urban and rural areas of Sindh, Pakistan nested within a cluster-randomized trial evaluating the effect of zinc and micronutrients on growth and morbidity (ClinicalTrials.gov Identifier: NCT00705445). The major findings were age-related with significant changes in alpha and beta diversity with increasing age. There was a significant increase in the relative abundance of the Firmicutes and Bacteroidetes phyla and a significant decrease in that of the Actinobacteria and Proteobacteria phyla (p < 0.0001). There were significant increases in the relative abundances of the major genera Bifidobacterium, Escherichia/Shigella and Streptococcus (p < 0.0001), and no significant change in the relative abundance of Lactobacillus. Using the LEfSE algorithm, differentially abundant taxa were identified between children in the first and second years of age, between those residing in rural and urban areas, and those who received different interventions at different ages from 3 to 24 months. The numbers of malnourished (underweight, wasted, stunted) or well-nourished children at each age, in each intervention arm, and at urban or rural sites were too small to determine if there were significant differences in alpha or beta diversity or differentially abundant taxa among them. Further longitudinal studies with larger numbers of well-nourished and malnourished children are required to fully characterize the intestinal microbiota of children in this region.


Assuntos
Microbioma Gastrointestinal , Desnutrição , Humanos , Criança , Pré-Escolar , Lactente , Paquistão , Projetos Piloto , Bactérias , Proteobactérias
5.
Infect Immun ; 90(11): e0039722, 2022 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-36286526

RESUMO

Cryptosporidium is a leading cause of diarrhea and death in young children and untreated AIDS patients and causes waterborne outbreaks. Pathogenic mechanisms underlying diarrhea and intestinal dysfunction are poorly understood. We previously developed stem-cell derived human intestinal enteroid (HIE) models for Cryptosporidium parvum which we used in this study to investigate the course of infection and its effect on intestinal epithelial integrity. By immunofluorescence and confocal microscopy, there was robust infection of undifferentiated and differentiated HIEs in two and three-dimensional (2D, 3D) models. Infection of differentiated HIEs in the 2D model was greater than that of undifferentiated HIEs but lasted only for 3 days, whereas infection persisted for 21 days and resulted in completion of the life cycle in undifferentiated HIEs. Infection of undifferentiated HIE monolayers suggest that C. parvum infects LGR5+ stem cells. Transepithelial electrical resistance measurement of HIEs in the 2D model revealed that infection resulted in decreased epithelial integrity which persisted in differentiated HIEs but recovered in undifferentiated HIEs. Compromised epithelial integrity was reflected in disorganization of the tight and adherens junctions as visualized using the markers ZO-1 and E-cadherin, respectively. Quantitation using the image analysis tools Tight Junction Organizational Rate and Intercellular Junction Organization Quantification, measurement of monolayer height, and RNA transcripts of both proteins by quantitative reverse transcription PCR confirmed that disruption persisted in differentiated HIEs but recovered in undifferentiated HIEs. These models, which more accurately recapitulate human infection, will be useful tools to dissect pathogenic mechanisms underlying diarrhea and intestinal dysfunction in cryptosporidiosis.


Assuntos
Criptosporidiose , Cryptosporidium parvum , Cryptosporidium , Criança , Humanos , Pré-Escolar , Criptosporidiose/genética , Cryptosporidium parvum/fisiologia , Intestinos , Diarreia/metabolismo , Mucosa Intestinal/metabolismo
6.
Sci Rep ; 11(1): 20540, 2021 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-34654825

RESUMO

In a prospective observational study, seroconversion to a specific pathogen can serve as a marker of an incident infection, whether or not that infection is symptomatic or clinically diagnosed. While self-reported symptoms can be affected by reporting bias, seroconversion is likely to be free of this bias as it is based on objective measurements of antibody response. Non-invasive salivary antibody tests can be used instead of serum tests to detect seroconversions in prospective studies. In the present study, individuals and families were recruited at a Lake Michigan beach in Wisconsin in August 2011. Data on recreational water exposure and baseline saliva samples (S1) were collected at recruitment. Follow-up data on gastrointestinal symptoms were collected via a telephone interview approximately 10 days post-recruitment. Follow-up saliva samples were self-collected approximately 2 weeks (S2) and 30-40 days post-recruitment (S3) and mailed to the study laboratory. Samples were analyzed for immunoglobulin (Ig) G responses to recombinant antigens of three noroviruses and Cryptosporidium, as well as protein purification tags as internal controls, using an in-house multiplex suspension immunoassay on the Luminex platform. Responses were defined as ratios of antibody reactivities with a target protein and its purification tag. Seroconversions were defined as at least four-fold and three-fold increases in responses in S2 and S3 samples compared to S1, respectively. In addition, an S2 response had to be above the upper 90% one-sided prediction limit of a corresponding spline function of age. Among 872 study participants, there were seven (0.8%) individuals with seroconversions, including six individuals with seroconversions to noroviruses and two to Cryptosporidium (one individual seroconverted to both pathogens). Among 176 (20%) individuals who reported swallowing lake water, there were six (3.4%) seroconversions compared to one (0.14%) seroconversion among the remaining 696 individuals: the crude and age-standardized risk differences per 1000 beachgoers were 32.7 (95% confidence limits 5.7; 59.6) and 94.8 (4.6; 276), respectively. The age-adjusted odds ratio of seroconversion in those who swallowed water vs. all others was 49.5 (4.5; 549), p = 0.001. Individuals with a norovirus seroconversion were more likely to experience vomiting symptoms within 4 days of the index beach visit than non-converters with an odds ratio of 34 (3.4, 350), p = 0.003. This study contributed further evidence that recreational water exposure is associated with symptomatic and asymptomatic waterborne infections, and that salivary antibody assays can be used in epidemiological surveys of norovirus and Cryptosporidium infections.


Assuntos
Infecções Assintomáticas/epidemiologia , Praias/estatística & dados numéricos , Infecções por Caliciviridae/epidemiologia , Criptosporidiose/epidemiologia , Saliva/imunologia , Adolescente , Adulto , Anticorpos/análise , Infecções por Caliciviridae/imunologia , Criança , Criptosporidiose/imunologia , Feminino , Humanos , Lagos/virologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Microbiologia da Água , Wisconsin/epidemiologia , Adulto Jovem
7.
Am J Trop Med Hyg ; 105(6): 1706-1711, 2021 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-34583337

RESUMO

In low-resource settings, Cryptosporidium spp. is a common cause of diarrheal disease in children under the age of 3 years. In addition to diarrhea, these children also experience subclinical episodes that have been shown to affect growth and cognitive function. In this study, we screened polymorphisms in the promoter and exon1 regions of the mannose binding lectin 2 (MBL2) gene, as well as single nucleotide polymorphisms (SNPs) described in toll-like receptors (TLR) TLR1, TLR2, TLR4, and TLR9 and TIR domain-containing adaptor protein (TIRAP) genes among children with cryptosporidial diarrhea (cases) and children who only experienced asymptomatic (subclinical) cryptosporidiosis (controls). Among the polymorphisms screened, the variant allele B at codon 54 (rs1800450) of the MBL2 gene was associated with susceptibility to cryptosporidial diarrhea (odds ratio [OR] = 2.2, 95% confidence interval [CI] 1.1-4.5). When plasma MBL levels were compared, 72% of cases were found to be deficient compared with 32% among controls (OR = 5.09). Among TLR polymorphisms screened, multivariate analysis showed that heterozygous genotypes of TLR4 896A/G (rs4986790, OR = 0.33, 95% CI: 0.11-0.98) and TIRAP 539 C/T (rs8177374, OR = 0.19, 95% CI: 0.06-0.64) SNPs were associated with protection from cryptosporidial diarrhea. Although not statistically significant, these findings suggest that polymorphisms of MBL2 and TLR genes influence susceptibility to symptomatic cryptosporidial diarrhea even in settings with high exposure levels. Further studies to validate these findings in a larger cohort and to understand the role of these polymorphisms in mediating innate and adaptive immune responses to cryptosporidial infection are necessary.


Assuntos
Criptosporidiose/genética , Diarreia/parasitologia , Lectina de Ligação a Manose/genética , Polimorfismo Genético , Receptores Toll-Like/genética , Imunidade Adaptativa , Estudos de Casos e Controles , Pré-Escolar , Estudos de Coortes , Criptosporidiose/imunologia , Criptosporidiose/metabolismo , Diarreia/genética , Humanos , Imunidade Inata , Índia , Lactente , Pobreza , Áreas de Pobreza , População Urbana
8.
Am J Trop Med Hyg ; 105(1): 196-203, 2021 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-34029209

RESUMO

The high burden of soil-transmitted helminth infections has been studied in India; however, little data exist on zoonotic helminths, and on animal-associated exposure to soil-transmitted helminths. Our study took place in the Jawadhu Hills, which is a tribal region in Tamil Nadu, India. Using a One Health approach, we included animal and environmental samples and human risk factors to answer questions about the associations among infected household soil, domestic animals, and human risk factors. Helminth eggs were identified by microscopy in animal and soil samples, and a survey about risk factors was administered to the head of the household. Contact with animals was reported in 71% of households. High levels of helminth infections were found across domestic animal species, especially in goats, chickens, and dogs. Helminth eggs were recorded in 44% of household soil (n = 43/97) and separately in 88% of soil near a water source (n = 28/32). Animal contact was associated with 4.05 higher odds of having helminth eggs in the household soil (P = 0.01), and also having a water source at the household was associated with a 0.33 lower odds of having helminth eggs in the household soil (P = 0.04). Soil moisture was a mediator of this association with a significant indirect effect (P < 0.001). The proportion mediated was 0.50. While our work does not examine transmission, these results support consideration of animal-associated exposure to STH and potentially zoonotic helminths in future interventions to reduce helminth burden. Our study provides support for further investigation of the effects of animals and animal fecal matter on human health.


Assuntos
Cestoides/isolamento & purificação , Fezes/parasitologia , Povos Indígenas/estatística & dados numéricos , Enteropatias Parasitárias/epidemiologia , Solo/parasitologia , Água/parasitologia , Zoonoses/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Criança , Pré-Escolar , Monitoramento Epidemiológico , Feminino , Helmintíase/epidemiologia , Humanos , Índia , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Saúde Única/estatística & dados numéricos , Contagem de Ovos de Parasitas , Vigilância da População , Fatores de Risco , Adulto Jovem
9.
Am J Clin Nutr ; 113(6): 1556-1564, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33668048

RESUMO

BACKGROUND: Environmental enteric dysfunction (EED) may influence growth during and recovery from moderate acute malnutrition (MAM), however, biomarkers to assess these relations have yet to be identified. OBJECTIVES: The objectives of this study were to: 1) develop a score for EED based on host fecal mRNA transcripts, 2) compare biomarkers of EED with each other, and 3) examine associations between the EED biomarkers and recovery from MAM and growth outcomes. METHODS: In a cohort of 520 Sierra Leonean MAM children, biomarkers of EED included the lactulose: mannitol (L: M) test, 15 host fecal mRNA transcripts, and host fecal proteins [α-1-antitrypsin (AAT), myeloperoxidase (MPO), neopterin (NEO)]. Anthropometry data were also collected and z scores were computed for length-for-age (LAZ) and weight-for-length (WLZ). Recovery from MAM was defined as midupper arm circumference ≥12.5 cm. Factor analysis was used to identify EED scores using the mRNA transcripts, and mixed effects regression was conducted to test for associations. RESULTS: The 15 host fecal mRNA transcripts were clustered into 3 scores: gut inflammation (GI) score, gut structure (GS) score, and gut defense (GD) score. We found agreement between certain inflammation markers (GI score and MPO), and permeability markers (GS score and AAT; AAT and the L: M excretion ratio). Antimicrobial gut defense (GD score) was inversely associated with percent lactulose excreted, a measure of intestinal permeability. LAZ (ß: -0.08; 95% CI: -0.14, -0.02) and WLZ (ß: -0.03; 95% CI: -0.06, -0.01) were negatively associated with GI score. A high GD score (ß: 0.36; 95% CI: 0.08, 0.64) and low AAT (ß: -1.35; 95% CI: -2.35, -0.36) were associated with recovery from MAM. CONCLUSIONS: Scores derived from host fecal mRNA transcript variably correlated with the L: M test and host fecal proteins. Markers of intestinal inflammation, permeability, and defense were associated with growth outcomes and recovery from MAM.


Assuntos
Desenvolvimento Infantil , Transtornos da Nutrição Infantil/complicações , Transtornos da Nutrição Infantil/epidemiologia , Enteropatias/epidemiologia , Enteropatias/etiologia , Biomarcadores/química , Criança , Transtornos da Nutrição Infantil/sangue , Fezes/química , Humanos , Inflamação/metabolismo , Permeabilidade , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Serra Leoa
11.
Curr Opin Microbiol ; 58: 124-129, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33113480

RESUMO

Cryptosporidium is a leading cause of diarrhea and death in young children and untreated AIDS patients in resource-poor settings, and of waterborne outbreaks of disease in developed countries. However, there is no consistently effective treatment for vulnerable populations. Progress towards development of therapeutics for cryptosporidiosis has been hampered by lack of optimal culture systems to study it. New advances in organoid/enteroid technology have contributed to improved platforms to culture and propagate Cryptosporidium. Here we discuss recent breakthroughs in the field and highlight different models for functional ex vivo organoid or enteroidderived culture systems. These systems will lead to a better understanding of the mechanisms of host-parasite interactions in vivo.


Assuntos
Técnicas de Cultura de Células/métodos , Criptosporidiose/parasitologia , Cryptosporidium/fisiologia , Intestinos/parasitologia , Organoides/parasitologia , Animais , Cryptosporidium/genética , Humanos , Modelos Biológicos
12.
Methods Mol Biol ; 2052: 373-402, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31452173

RESUMO

Conventional cell cultures utilizing transformed or immortalized cell lines or primary human epithelial cells have played a fundamental role in furthering our understanding of Cryptosporidium infection. However, they remain inadequate with respect to their inability to emulate in vivo conditions, support long-term growth, and complete the life cycle of the parasite. Previously, we developed a 3D silk scaffold-based model using transformed human intestinal epithelial cells (IECs). This model supported C. parvum infection for up to 2 weeks and resulted in completion of the life cycle of the parasite. However, transformed IECs are not representative of primary human IEC.Human intestinal enteroids (HIEs) are cultures derived from crypts that contain Lgr5+ stem cells isolated from human biopsies or surgical intestinal tissues; these established multicellular cultures can be induced to differentiate into enterocytes, enteroendocrine cells, goblet cells, Paneth cells, and tuft cells. HIEs better represent human intestinal structure and function than immortalized IEC lines. Recently, significant progress has been made in the development of technologies to culture HIEs in vitro. When grown in a 3D matrix, HIEs provide a spatial organization resembling the native human intestinal epithelium. Additionally, they can be dissociated and grown as monolayers in tissue culture plates, permeable supports or silk scaffolds that enable mechanistic studies of pathogen infections. They can also be co-cultured with other human cells such as macrophages and myofibroblasts. The HIEs grown in these novel culture systems recapitulate the physiology, the 3D architecture, and functional diversity of native intestinal epithelium and provide a powerful and promising new tool to study Cryptosporidium-host cell interactions and screen for interventions ex vivo. In this chapter, we describe the 3D silk scaffold-based model using transformed IEC co-cultured with human intestinal myofibroblasts and 2D and 3D HIE-derived models of Cryptosporidium, also co-cultured with human intestinal myofibroblasts.


Assuntos
Técnicas de Cultura de Células/métodos , Cryptosporidium/crescimento & desenvolvimento , Células Epiteliais/parasitologia , Mucosa Intestinal/parasitologia , Organoides , Engenharia Tecidual/métodos , Linhagem Celular , Células Cultivadas , Técnicas de Cocultura/métodos , Cryptosporidium/genética , Cryptosporidium/patogenicidade , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Células Epiteliais/ultraestrutura , Humanos , Mucosa Intestinal/citologia , Mucosa Intestinal/fisiologia , Microscopia Eletrônica de Varredura , Miofibroblastos , Oocistos/crescimento & desenvolvimento , Receptores Acoplados a Proteínas G/metabolismo , Esporozoítos/isolamento & purificação , Células-Tronco/citologia , Células-Tronco/metabolismo , Alicerces Teciduais , Fluxo de Trabalho
13.
Int J Parasitol ; 50(1): 47-54, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31756313

RESUMO

Soil-transmitted helminth infections propagate poverty and slow economic growth in low-income countries. As with many other neglected tropical diseases, environmental conditions are important determinants of soil-transmitted helminth transmission. Hence, remotely sensed data are commonly utilised in spatial risk models intended to inform control strategies. In the present study, we build upon the existing modelling approaches by utilising fine spatial resolution Landsat 8 remotely sensed data in combination with topographic variables to predict hookworm prevalence in a hilly tribal area in southern India. Hookworm prevalence data collected from two field surveys were used in a random forest model to investigate the predictive capacity of 15 environmental variables derived from two remotely sensed images acquired during dry and rainy seasons. A variable buffer radius (100-1000 m) was applied to the point-prevalence locations in order to integrate environmental conditions around the village centroids into the modelling approach and understand where transmission is more likely. Elevation and slope were the most important variables in the models, with lower elevation and higher slope correlating with higher transmission risk. A modified normalised difference water index was among other recurring important variables, likely responsible for some seasonal differences in model performance. The 300 m buffer distance produced the best model performance in this setting, with another spike at 700 m, and a marked drop-off in R2 values at 1000 m. In addition to assessing a large number of environmental correlates with hookworm transmission, the study contributes to the development of standardised methods of spatial linkage of continuous environmental data with point-based disease prevalence measures for the purpose of spatially explicit risk profiling.


Assuntos
Ancylostomatoidea/parasitologia , Infecções por Uncinaria/epidemiologia , Solo/parasitologia , Animais , Humanos , Índia , Modelos Estatísticos , Doenças Negligenciadas , Prevalência , Fatores de Risco
14.
Artigo em Inglês | MEDLINE | ID: mdl-31684018

RESUMO

Systematically collected hospitalization records provide valuable insight into disease patterns and support comprehensive national infectious disease surveillance networks. Hospitalization records detailing patient's place of residence (PoR) can be utilized to better understand a hospital's case load and strengthen surveillance among mobile populations. This study examined geographic patterns of patients treated for cholera at a major hospital in south India. We abstracted 1401 laboratory-confirmed cases of cholera between 2000-2014 from logbooks and electronic health records (EHRs) maintained by the Christian Medical College (CMC) in Vellore, Tamil Nadu, India. We constructed spatial trend models and identified two distinct clusters of patient residence-one around Vellore (836 records (61.2%)) and one in Bengal (294 records (21.5%)). We further characterized differences in peak timing and disease trend among these clusters to identify differences in cholera exposure among local and visiting populations. We found that the two clusters differ by their patient profiles, with patients in the Bengal cluster being most likely older males traveling to Vellore. Both clusters show well-aligned seasonal peaks in mid-July, only one week apart, with similar downward trend and proportion of predominant O1 serotype. Large hospitals can thus harness EHRs for surveillance by utilizing patients' PoRs to study disease patterns among resident and visitor populations.


Assuntos
Cólera/epidemiologia , Hospitalização/estatística & dados numéricos , Adolescente , Adulto , Criança , Pré-Escolar , Registros Eletrônicos de Saúde , Feminino , Humanos , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Sorogrupo , Adulto Jovem
15.
F1000Res ; 72018.
Artigo em Inglês | MEDLINE | ID: mdl-30228873

RESUMO

The intestinal apicomplexan parasite Cryptosporidium is a major cause of diarrheal disease in humans worldwide. However, treatment options are severely limited. The search for novel interventions is imperative, yet there are several challenges to drug development, including intractability of the parasite and limited technical tools to study it. This review addresses recent, exciting breakthroughs in this field, including novel cell culture models, strategies for genetic manipulation, transcriptomics, and promising new drug candidates. These advances will stimulate the ongoing quest to understand Cryptosporidium and the pathogenesis of cryptosporidiosis and to develop new approaches to combat this disease.


Assuntos
Antiprotozoários/uso terapêutico , Criptosporidiose/prevenção & controle , Cryptosporidium/efeitos dos fármacos , Descoberta de Drogas , Animais , Criptosporidiose/parasitologia , Cryptosporidium/isolamento & purificação , Humanos
16.
Water Res ; 142: 289-300, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-29890477

RESUMO

Quantifying sporadic waterborne infections in community settings can be challenging. Salivary antibody immunoassays are a promising non-invasive tool that can be used in prospective studies of common infections, especially those involving children. This study was conducted in a Massachusetts city, which uses a microbiologically contaminated river as its water source, during summer-early winter periods before and after construction of a new drinking water treatment plant. Monthly saliva samples (7480 samples from 1170 children and 816 adults) were analyzed for immunoglobulin G (IgG) responses to recombinant proteins of Cryptosporidium, one genogroup I (GI) and two GII noroviruses. Immunoconversion was defined as at least four-fold increase in specific antibody responses between two monthly samples with a post-conversion response above a flexible age-dependent cut-off. Episodes of gastroenteritis (diarrhea or vomiting or cramps) were associated with 3.2 (95% confidence limits 1.1; 9.5) adjusted odds ratio (aOR) of immunoconversion to Cryptosporidium; episodes of combined diarrhea and vomiting symptoms were associated with 3.5 (0.8; 15.0) and 4.6 (1.7; 12.6) aORs of an immunoconversion to GI and GII noroviruses, respectively. Swimming in natural water bodies or chlorinated pools was associated with 2.3 (0.4; 15.4) and 4.9 (1.6; 15.5) aORs of immunoconversion to Cryptosporidium, respectively. In a subset of study participants who did not use home water filters, consumption of at least some amount of non-boiled tap water reported in a monthly recall survey was associated with 11.1 (1.2; 100.0) and 0.6 (0.1; 2.5) aORs of immunoconversion to Cryptosporidium before and after the new water treatment plant construction, respectively. Among individuals who used home water filters, associations between non-boiled tap water consumption and Cryptosporidium immunoconversion were not significant before and after new plant construction with aORs of 0.8 (0.2; 3.3) and 0.3 (0.1; 1.6), respectively. The interaction effect of study phase and non-boiled tap water consumption on Cryptosporidium immunoconversions was statistically significant in the entire study population with aOR of 5.4 (1.1; 25.6). This was the first study that has used a salivary antibody immunoassay to demonstrate significant associations between gastrointestinal symptoms and Cryptosporidium and norovirus infections, and between water-related exposures and Cryptosporidium infections.


Assuntos
Infecções por Caliciviridae/diagnóstico , Criptosporidiose/diagnóstico , Imunoensaio/métodos , Doenças Transmitidas pela Água/diagnóstico , Adolescente , Adulto , Animais , Infecções por Caliciviridae/etiologia , Criança , Criptosporidiose/etiologia , Diarreia/parasitologia , Diarreia/virologia , Água Potável/parasitologia , Água Potável/virologia , Feminino , Gastroenterite/parasitologia , Gastroenterite/virologia , Humanos , Masculino , Massachusetts , Pessoa de Meia-Idade , Estudos Prospectivos , Recreação , Rios/parasitologia , Rios/virologia , Saliva/parasitologia , Saliva/virologia , Doenças Transmitidas pela Água/parasitologia , Doenças Transmitidas pela Água/virologia
17.
Mol Biochem Parasitol ; 221: 56-65, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29581010

RESUMO

Cryptosporidium spp. are the causative agents of diarrheal disease worldwide, but effective treatments are lacking. Cryptosporidium employs mucin-like glycoproteins with O-glycans to attach to and infect host intestinal epithelial cells. The Tn antigen (GalNAcα1-Ser/Thr) is an O-glycan essential for these processes, as Tn-specific lectins and a Tn-specific monoclonal antibody block attachment to and infection of host cells in vitro. The enzymes in Cryptosporidium catalyzing their synthesis, however, have not been studied. Previously, we identified four genes encoding putative UDP N-acetyl-α-d-galactosamine:polypeptide N-acetylgalactosaminyltransferases (ppGalNAc-Ts) in the genomes of three Cryptosporidium spp. Here we report the in silico analysis, cloning, expression, purification, and characterization of one of the four enzymes Cryptosporidium parvum (Cp)-ppGalNAc-T4. This enzyme contains the characteristic domains and motifs conserved in ppGalNAc-Ts and is expressed at multiple time points during in vitro infection. Recombinant soluble Cp-ppGalNAc-T4 was enzymatically active against an unmodified EA2 peptide suggesting that it may function as an "initiating" ppGalNAc-T. Cp-ppGalNAc-T4 also exhibited a strong preference for UDP-GalNAc over other nucleotide sugar donors and was active against unmodified and O-glycosylated versions of the C. parvum gp40-derived peptide, with a preference for the former, suggesting it may play a role in modifying this glycoprotein in vivo. Given the importance of mucin-type O-glycosylation in Cryptosporidium spp., the enzymes that catalyze their synthesis may serve as potential therapeutic targets.


Assuntos
Cryptosporidium parvum/enzimologia , N-Acetilgalactosaminiltransferases/genética , N-Acetilgalactosaminiltransferases/metabolismo , Uridina Difosfato N-Acetilgalactosamina/metabolismo , Antígenos Glicosídicos Associados a Tumores/metabolismo , Clonagem Molecular , Cryptosporidium parvum/genética , Células Epiteliais/metabolismo , Expressão Gênica , Perfilação da Expressão Gênica , Células HEK293 , Humanos , Modelos Moleculares , N-Acetilgalactosaminiltransferases/química , N-Acetilgalactosaminiltransferases/isolamento & purificação , Conformação Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Especificidade por Substrato , Polipeptídeo N-Acetilgalactosaminiltransferase
18.
PLoS One ; 12(8): e0182642, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28820902

RESUMO

Despite availability of high quality medical records, health care systems often do not have the resources or tools to utilize these data efficiently. Yet, hospital-based, laboratory-confirmed records may pave the way for building reliable surveillance systems capable of monitoring temporal trends of emerging infections. In this communication, we present a new tool to compress and visualize medical records with a local population profile (LPP) approach, which transforms information into statistically comparable patterns. We provide a step-by-step tutorial on how to build, interpret, and expand the use of LPP using hospitalization records of laboratory-confirmed cholera. We abstracted case information from the databases maintained by the Department of Clinical Microbiology at Christian Medical College in Vellore, India. We used a single-year age distribution to construct LPPs for O1, O139, and non O1/O139 serotypes of Vibrio cholerae. Disease counts and hospitalization rates were converted into fitted kernel-based probability densities. We formally compared LPPs with the Kolmogorov-Smirnov test, and created multi-panel visuals to depict temporal trend, age distribution, and hospitalization rates simultaneously. Our first implementation of LPPs revealed information that is typically gathered from surveillance systems such as: i) estimates of the demographic distribution of diseases and identification of a population at risk, ii) changes in the dominant pathogen presence; and iii) trends in disease occurrence. The LPP demonstrated the benefit of increased resolution in pattern detection of disease for different Vibrio cholerae serotypes and two demographic categories by showing patterns and anomalies that would be obscured by traditional methods of analysis and visualization. LPP can be used effectively to compile basic patient information such as age, sex, diagnosis, location, and time into compact visuals. Future development of the proposed approach will allow public health researchers and practitioners to broadly utilize and efficiently compress large volumes of medical records without loss of information.


Assuntos
Cólera/epidemiologia , Hospitalização , Prontuários Médicos , Vigilância da População , Humanos , Índia/epidemiologia
19.
Trends Parasitol ; 33(9): 662-664, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28750950

RESUMO

The pyrazolopyridine KDU731 is a promising drug candidate for treatment of diarrhea caused by Cryptosporidium in young children in the resource-limited world. KDU731, a PI (4) kinase inhibitor, blocks Cryptosporidium infection in vitro and in vivo in immunocompromised mice and dramatically reduces oocyst shedding, diarrhea, and dehydration in neonatal calves.


Assuntos
Criptosporidiose/complicações , Criptosporidiose/tratamento farmacológico , Diarreia/tratamento farmacológico , Diarreia/etiologia , Pirazóis/uso terapêutico , Piridinas/uso terapêutico , Animais , Bovinos , Doenças dos Bovinos/tratamento farmacológico , Cryptosporidium/efeitos dos fármacos , Desidratação/tratamento farmacológico , Desidratação/etiologia , Humanos , Hospedeiro Imunocomprometido , Camundongos , Pirazóis/farmacologia , Piridinas/farmacologia
20.
Arch Virol ; 162(9): 2875-2879, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28477174

RESUMO

Bisegmented dsRNA viruses that infect most or all isolates of apicomplexan parasite Cryptosporidium parvum are currently assigned to a single species, Cryptosporidium parvum virus 1, in genus Cryspovirus, family Partitiviridae. An analysis of existing sequence data suggested that the complete sequences of both cryspovirus genome segments, dsRNA1 and dsRNA2, had yet to be determined. We therefore set out to accomplish this for the virus strain that infects C. parvum isolate Iowa. The results suggest that several previous cryspovirus sequences are indeed truncated at one or both segment termini and also identify sequences at or near the termini that are conserved in both segments. Complete sequences of other cryspovirus strains, including ones from other Cryptosporidium species, are needed for refining their classification into one or more virus species.


Assuntos
Cryptosporidium parvum/virologia , Genoma Viral , Vírus de RNA/genética , Vírus de RNA/isolamento & purificação , Sequência de Bases , Filogenia , RNA Viral/genética
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