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Probiotics are live microorganisms that, when administered in sufficient doses, provide health benefits on the host. The United States Food and Drug Administration (FDA) requires phase I safety studies for probiotics when the intended use of the product is as a drug. The purpose of the study was to determine the safety of Bifidobacterium animalissubsp lactis(B. lactis) strain BB-12 (BB-12)-supplemented yogurt when consumed by a generally healthy group of adults who were prescribed a 10-day course of antibiotics for a respiratory infection. Secondary aims were to assess the ability of BB-12 to affect the expression of whole blood immune markers associated with cell activation and inflammatory response. A phase I, double-blinded, randomized controlled study was conducted in compliance with FDA guidelines for an Investigational New Drug (IND). Forty participants were randomly assigned to consume 4 ounces of either BB-12 -supplemented yogurt or non-supplemented control yogurt daily for 10 d. The primary outcome was to assess safety and tolerability, assessed by the number of reported adverse events. A total of 165 non-serious adverse events were reported, with no differences between the control and BB-12 groups. When compared to the control group, B lactisfecal levels were modestly higher in the BB-12-supplemented group. In a small subset of patients, changes in whole blood expression of genes associated with regulation and activation of immune cells were detected in the BB-12-supplemented group. BB-12-supplemented yogurt is safe and well tolerated when consumed by healthy adults concurrently taking antibiotics. This study will form the basis for future randomized clinical trials investigating the potential immunomodulatory effects of BB-12-supplemented yogurt in a variety of disease states.

Diarrhea is a leading cause of mortality and morbidity in children younger than 5 years in impoverished regions of the world. Our aim was to compare the fecal microbiota of healthy children with that of children with clinical diarrhea in a population from a tropical highland in Colombia, South America. Our hypothesis was that a reduced prevalence of inherent Lactobacillusand Bifidobacteriumspecies would be associated with enteric viral and bacterial pathogens.

Diarrhea is a leading cause of mortality and morbidity in children younger than 5 years in impoverished regions of the world. Our aim was to compare the fecal microbiota of healthy children with that of children with clinical diarrhea in a population from a tropical highland in Colombia, South America. Our hypothesis was that a reduced prevalence of inherent Lactobacillusand Bifidobacteriumspecies would be associated with enteric viral and bacterial pathogens. Children between 1 and 5 years of age from 2 different locations were evaluated for presence of clinical diarrhea. Nucleic acid, isolated from fecal samples, was used to determine by molecular protocols the abundance of inherent bacterial species and presence of enteric pathogens compared with clinically healthy children. The effect of host demographic factors on incidence of diarrhea was also analyzed. The composition of the fecal microbiota was affected by host demographic factors: age, health status, location, and sex. In partial support of our hypothesis, the relative abundance of commensal Bifidobacteriumand Lactobacillusspecies was inversely correlated with incidence of diarrhea regardless of location. Our results suggested that changes in fecal microbiota composition of children with clinical diarrhea are associated with certain demographic factors that should be considered before designing a prophylactic intervention. Delivery of certain Lactobacillusspecies and Bifidobacteriumspecies or a diet rich in bifidogenic components that promote growth of Bifidobacteriumspecies could provide a prophylactic effect to ameliorate the effect of diarrhea in children at risk.

The influence of the distribution of carbon black between phases of binary heterogeneous blends of polyethylene with elastomers on the viscosity of their melts was studied.

Giardia duodenalisis a pathogenic intestinal protozoan parasite of humans and many other animals. Giardia duodenalisis found throughout the world, and infection is known to have adverse health consequences for human and other mammalian hosts. Yet, many aspects of the biology of this ubiquitous parasite remain unresolved. Whole genome sequencing and comparative genomics can provide insight into the biology of G. duodenalisby helping to reveal traits that are shared by all G. duodenalisassemblages or unique to an individual assemblage or strain. However, these types of analyses are currently hindered by the lack of available G. duodenalisgenomes, due, in part, to the difficulty in obtaining the genetic material needed to perform whole genome sequencing. In this study, a novel approach using a multistep cleaning procedure coupled with a hybrid sequencing and assembly strategy was assessed for use in producing high quality G. duodenalisgenomes directly from cysts obtained from feces of two naturally infected hosts, a cat and dog infected with assemblage A and D, respectively. Cysts were cleaned and concentrated using cesium chloride gradient centrifugation followed by immunomagnetic separation. Whole genome sequencing was performed using both Illumina MiSeq and Oxford Nanopore MinION platforms. A hybrid assembly strategy was found to produce higher quality genomes than assemblies from either platform alone. The hybrid G. duodenalisgenomes obtained from fecal isolates (cysts) in this study compare favorably for quality and completeness against reference genomes of G. duodenalisfrom cultured isolates. The whole genome assembly for assemblage D is the most contiguous genome available for this assemblage and is an important reference genome for future comparative studies. The data presented here support a hybrid sequencing and assembly strategy as a suitable method to produce whole genome sequences from DNA obtained from G. duodenaliscysts which can be used to produce novel reference genomes necessary to perform comparative genomics studies of this parasite.

Giardia duodenalisis an enteric protozoan parasite commonly found in humans and many other animals around the world. The parasite is grouped into genetically related strains called assemblages which display differing degrees of host specificity. Although mixed assemblage infections have been documented the full extent of the occurrence and importance of mixed infections remains to be characterized as current sequencing technologies lack the sensitivity to readily detect mixed infections. Here we have developed a next generation amplicon sequencing (NGS) protocol and analysis pipeline for detecting Giardiaassemblages using the beta-giardin gene. NGS was validated using 37 isolates that included Giardia murisand six assemblages (A-F) of Giardia duodenalisobtained from seven different hosts. NGS was compared to traditional PCR and direct Sanger sequencing for its ability to detect Giardiaspecies, assemblages, and mixed assemblage infections. We demonstrate that NGS works as well as PCR and Sanger sequencing for assemblage detection as the same assemblage was observed in all samples by both methods. NGS has the further benefit of detecting mixed assemblage infections, low abundance assemblages, and intra-assemblage variation in samples which would have been missed using direct Sanger sequencing alone. NGS represents a powerful new tool for exploring Giardiainfections not only in infected hosts but also in environmental specimens which may aide in understanding Giardiaepidemiology.