Tryptophan Metabolites And Their Predicted Microbial Sources In Fecal Samples From Healthy Individuals.

Gut microbiota produce tryptophan metabolites (TMs) important to homeostasis. However, measuring TM levels in stool and determining their microbial sources can be difficult. Here, we measured TMs from the indole pathway in fecal samples from 21 healthy adults with the goal to: 1) determine fecal TM concentrations in healthy individuals; 2) link TM levels to bacterial abundance using 16S and whole genome shotgun (WGS) sequencing data; and 3) predict likely bacterial sources of TM production.

Fully resolved assembly of Cryptosporidium parvum.

Background: Cryptosporidium parvum is an apicomplexan parasite commonly found across many host species with a global infection prevalence in human populations of 7.6%. Understanding its diversity and genomic makeup can help in fighting established infections and prohibiting further transmission.

Prevalence of Clostridium difficile infections among Kenyan children with diarrhea.

Background: Diarrhea causes significant morbidity and mortality among children worldwide. Regions most affected by diarrhea include Sub-Saharan Africa and Southeast Asia, where antibiotics are in common use and can make children more vulnerable to Clostridium difficile and pathogens that are not affected by these drugs. Indeed, C.

Adenovirus 36 antibody detection: Improving the standard serum neutralization assay.

Adenovirus 36 (AdV36) causes weight gain in animal models, including non-human primates. In humans, AdV36-neutralizing antibodies are associated with adiposity; however, longitudinal studies in large populations are needed to clarify AdV36's contribution. The current gold standard for detection of AdV36-specific antibody is the serum neutralization assay (SNA), which requires long incubation times and highly trained personnel.

Fecal Indole as a Biomarker of Susceptibility to Cryptosporidium Infection.

Cryptosporidium causes significant diarrhea worldwide, especially among children and immunocompromised individuals, and no effective drug treatment is currently available for those who need it most. In this report, previous volunteer infectivity studies have been extended to examine the association between fecal indole and indole-producing (IP) gut microbiota on the outcome of a Cryptosporidium infection. Fecal indole concentrations (FICs) of 50 subjects and 19 taxa of common gut microbiota, including six IP taxa (11 subjects) were determined in stool samples collected before and after a challenge with Cryptosporidium oocysts.

A rapid and specific method for the detection of indole in complex biological samples.

Indole, a bacterial product of tryptophan degradation, has a variety of important applications in the pharmaceutical industry and is a biomarker in biological and clinical specimens. Yet, specific assays to quantitate indole are complex and require expensive equipment and a high level of training. Thus, indole in biological samples is often estimated using the simple and rapid Kovács assay, which nonspecifically detects a variety of commonly occurring indole analogs.

Cryptosporidium muris: infectivity and illness in healthy adult volunteers.

Although Cryptosporidium parvum and C. hominis cause the majority of human cryptosporidiosis cases, other Cryptosporidium species are also capable of infecting humans, particularly when individuals are immunocompromised. Ten C.

Cryptosporidium meleagridis: infectivity in healthy adult volunteers.

Most Cryptosporidium infections in humans are caused by C. parvum or C. hominis.

Texas needs physicians trained in public health: a new 4-year integrated MD/MPH degree program.

Traditionally, medicine and public health have not worked as synergistic disciplines because they are based on fundamentally different models. However, a number of very recent imperatives emphasize the need for dual training in these fields to address major public health problems facing society as well as the documented and forecasted workforce shortages. In response to this need, two University of Texas institutions based in San Antonio, Texas, partnered in 2007 to offer a dual 4-year Doctor of Medicine/Master of Public health (MD/MPH) degree program, one of a handful in the nation.

Cryptosporidium muris in a Texas canine population.

Molecular technology has led to the discovery of previously unrecognized Cryptosporidium species in new hosts, such as C. canis in humans. The notion that dogs may transmit Cryptosporidium species to humans has significant public health implications, and additional studies are merited.

Cryptosporidium hominis: experimental challenge of healthy adults.

Cryptosporidium hominis causes diarrhea in humans and has been associated with community outbreaks. This study describes the infectivity, illness, and serologic response after experimental challenge of 21 healthy adult volunteers with 10-500 C. hominis (TU502) oocysts.

High levels of CXCL10 are produced by intestinal epithelial cells in AIDS patients with active cryptosporidiosis but not after reconstitution of immunity.

Chemokines play key roles in attracting immune cells to sites of infections. However, few data on chemokine expression in the gut during human infections are available. We examined expression of chemokines in intestinal tissues of AIDS patients during active Cryptosporidium infection and during resolution of such an infection.

Evaluation of recombinant oocyst protein CP41 for detection of cryptosporidium-specific antibodies.

Cryptosporidium is an important cause of diarrhea in developed and developing countries, and its epidemiology is of interest. The methodologies used in the detection of Cryptosporidium-specific antibodies vary widely, which complicates comparison of results. This study assesses the performance of a Cryptosporidium recombinant protein (rCP41) in a serological assay compared to that of a crude antigen preparation.

Cryptosporidiosis in children.

Cryptosporidiosis is an important enteric parasitic infection that is associated with significant morbidity and mortality, especially among individuals who are immunosuppressed and infants and children in the developing world. The seroprevalence of this pathogen is high worldwide, suggesting that exposure occurs commonly. The routes of Cryptosporidium spp.

Combined use of enzyme-linked immunosorbent assay and flow cytometry to detect antibodies to Trypanosoma cruzi in domestic canines in Texas.

Canines may be sentinels and/or reservoirs for human Trypanosoma cruzi exposures. This study adapted a method originally designed for human diagnostics to detect serum immunoglobulin G to T. cruzi in canines.

Antibody response of healthy adults to recombinant thrombospondin-related adhesive protein of cryptosporidium 1 after experimental exposure to cryptosporidium oocysts.

Thrombospondin-related adhesive protein of Cryptosporidium 1 (TRAP-C1) belongs to a group of proteins that are also found in Toxoplasma gondii, Eimeria tenella, and Plasmodium species. TRAP-related proteins are needed for gliding motility, host-cell attachment, and invasion. The objective of this study was to characterize the antibody response to recombinant TRAP-C1 (rTRAP-C1) in healthy volunteers exposed to C.

Substance P expression correlates with severity of diarrhea in cryptosporidiosis.

Cryptosporidiosis, caused by Cryptosporidium parvum, is self-limited in immunocompetent hosts but may cause chronic diarrhea in patients with acquired immunodeficiency syndrome (AIDS). Substance P (SP), a neuropeptide belonging to the tachykinin family, is expressed in gastrointestinal tract and can cause electrogenic chloride anion secretion. Therefore, we studied SP mRNA and protein expression in jejunal tissue samples of patients with AIDS with naturally occurring chronic cryptosporidiosis and healthy volunteers with mild cryptosporidiosis or asymptomatic infection after experimental C.

Cryptosporidiosis.

Purpose Of Review: Cryptosporidiosis is a self-limited diarrheal disease that occurs in the community setting but can be chronic and potentially serious in immunocompromised patients. Community outbreaks are often associated with water-borne transmission. Cryptosporidium research has increased dramatically since the human disease was first recognized in 1976.

Interleukin-8, tumor necrosis factor-alpha, and lactoferrin in immunocompetent hosts with experimental and Brazilian children with acquired cryptosporidiosis.

To examine the importance of intestinal inflammation in the diagnosis and pathogenesis of human cryptosporidiosis, stools of healthy adult volunteers before and after experimental infection were tested for fecal lactoferrin, interleukin-8 (IL-8), and tumor necrosis factor-alpha (TNF-alpha). Stool samples of Brazilian children with well-defined Cryptosporidium infection, with or without diarrhea, were also tested for IL-8 and TNF-alpha. Only one of the 14 volunteers challenged with Cryptosporidium had increased fecal lactoferrin.

Characterization of aminopeptidase activity from three species of microsporidia: Encephalitozoon cuniculi, Encephalitozoon hellem, and Vittaforma corneae.

Microsporidia are obligate intracellular parasites of the phylum Microspora. To date, more than 1,200 species within 144 genera have been described, with 14 infecting humans. Currently, no effective treatment exists for human microsporidiosis.

Cryptosporidium dose-response studies: variation between hosts.

The issue of variation is highly important in dose-response analysis: variation among genetically related pathogens infecting the same host, but also variation among hosts, in susceptibility to infection by the same pathogen. This latter issue is addressed here for the protozoan parasite Cryptosporidium parvum, the causative agent for many outbreaks of water-borne gastrointestinal illness. In human feeding studies, infectivity has been shown to be low in subjects with high preexisting anti-Cryptosporidium IgG-levels.

Cryptosporidium dose response studies: variation between isolates.

The infectivity of three different isolates of the waterborne protozoan parasite Cryptosporidium parvum has been tested in human feeding studies. These three isolates (Iowa, TAMU, and UCP) have different ID50s, indicating substantial variation in their infectivity for humans. This finding is of great importance for quantitative risk assessment as it provides strong evidence for heterogeneity in infectivity among isolates of the same species.