Enhanced GII.4 human norovirus infection in gnotobiotic pigs transplanted with a human gut microbiota

The role of commensal microbiota in enteric viral infections has been explored extensively, but the interaction between human gut microbiota (HGM) and human norovirus (HuNoV) is poorly understood. In this study, we established an HGM-Transplanted gnotobiotic (Gn) pig model of HuNoV infection and disease, using an infant stool as HGM transplant and a HuNoV GII.4/2006b strain for virus inoculation. Compared to germ-free Gn pigs, HuNoV inoculation in HGMT Gn pigs resulted in increased HuNoV shedding, characterized by significantly higher shedding titres on post inoculation day (PID) 3, 4, 6, 8 and 9, and significantly longer mean duration of virus shedding. In addition, virus titres were significantly higher in duodenum and distal ileum of HGMT Gn pigs on PID10, while comparable and transient HuNoV viremia was detected in both groups. 16S rRNA gene sequencing demonstrated that HuNoV infection dramatically altered intestinal microbiota in HGMT Gn pigs at the phylum (Proteobacteria, Firmicutes and Bacteroidetes) and genus (Enterococcus, Bifidobacterium, Clostridium, Ruminococcus, Anaerococcus, Bacteroides and Lactobacillus) levels. In summary, enhanced GII.4 HuNoV infection was observed in the presence of HGM, and host microbiota was susceptible to disruption upon HuNoV infection

Mechanisms and microenvironment investigation of cellularized high density gradient collagen matrices via densification

Biological tissues and biomaterials are often defined by unique spatial gradients in physical properties that impart specialized function over hierarchical scales. The structure of these materials forms continuous transitional gradients and discrete local microenvironments between adjacent (or within) tissues, and across matrix-cell boundaries, which is difficult to replicate with common scaffold systems. Here, the matrix densification of collagen leading to gradients in density, mechanical properties, and fibril morphology is studied. High-density regions form via a fluid pore pressure and flow-driven mechanism, with increased relative fibril density (10x), mechanical properties (20x, to 94.40 +/- 18.74 kPa), and maximum fibril thickness (1.9x, to >1 mu m) compared to low-density regions, while maintaining porosity and fluid/mass transport to support viability of encapsulated cells. Similar to the organization of the articular cartilage zonal structure, it is found that high-density collagen regions induce cell and nuclear alignment of primary chondrocytes. Chondrocyte gene expression is maintained in collagen matrices, and no phenotypic changes are observed as a result of densification. Collagen densification provides a tunable platform for the creation of gradient systems to study complex cell-matrix interactions. These methods are easily generalized to compression and boundary condition modalities useful to mimic a broad range of tissues

Taiwan Aboriginals and Peoples of the Pacific-Asia Region: Multivariate Craniometric Comparisons.

RefereedStepwise discriminant function analysis and Mahalanobis’s generalized distance are applied to twenty-nine cranial measurements recorded in 2,531 male crania representing five Taiwan aboriginal cranial series and fifty prehistoric, modern, and near modern human groups. The Taiwan aboriginal cranial series include modern samples of Atayal, Bunun, Pazeh, Babuza, and archaeological human remains from the Shi San Hang site (ca 1800-500 BP). The comparative cranial series represent East Asia, Southeast Asia, Australia, New Guinea, island Melanesia, Polynesia, and Micronesia. The results of two separate analyses, one using five and the other using fifty-five groups, are presented. A relatively close connection between the Babuza, Pazeh, and Shi San Hang aboriginal cranial series is observed while the Atayal and Bunun series remain relatively well differentiated. Connections between Taiwan aboriginal groups and cranial series from Polynesia suggest that Taiwan’s aboriginal inhabitants may have been the ancestral source of these inhabitants of Remote Oceania. Similarly, these results suggest that the ultimate source of Taiwan’s prehistoric and modern aboriginal groups may be among the early inhabitants of eastern (Northeast or Southeast) Asia. The results of the present craniometric analysis are compared with other lines of evidence which have been used to examine the affinities and origins of Taiwan’s aboriginal peoples