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A Gram-stain-negative, aerobic, rod-shaped bacterium, designated strain YQF-2T, was isolated from coastal sediment sampled in Jiangsu Province and characterized phylogenetically and phenotypically. Optimal bacterial growth occurred at 28 °C (range 4–38 °C) and pH 7 (pH 6–10). Phylogenetic analysis based on 16S rRNA gene sequences showed that strain YQF-2T was related to members of the genus Rheinheimera and shared the highest sequence identities with Rheinheimera pacifica KMM 1406T (98.6%), followed by Rheinheimera aestuarii H29T (98.4%), Rheinheimera japonica KMM 9513T (98.3%), Rheinheimera aquimaris SW-353T (98.3%), Rheinheimera hassiensis E48T (97.8%) and Rheinheimera muenzenbergensis E49T (97.7%). The 16S rRNA gene sequence identities between strain YQF-2T and other members of the genus Rheinheimera were below 97.2%. The digital DNA–DNA hybridization value between strain YQF-2T and R. pacifica KMM 1406T was 23.3±2.3%. The average nucleotide identity value between strain YQF-2T and R. pacifica KMM 1406T was 79.7%. The unique respiratory quinone was ubiquinone-8. Phosphatidylethanolamine and phosphatidylglycerol were identified as the major polar lipids. The strain had summed feature 3 (C16:1 ω7c and/or C16:1 ω6c), summed feature 8 (C18:1 ω7c and/or C18:1 ω6c), C16:0, C12:0 3-OH and iso-C17:0 3-OH as major fatty acids. The G+C content of the genomic DNA was 50.0 mol%. On the basis of phenotypic, genotypic and phylogenetic evidence, strain YQF-2T represents a novel species of the genus Rheinheimera , for which the name Rheinheimera lutimaris sp. nov. is proposed, with the type strain YQF-2T (=KCTC 72184T=MCCC 1K03663T).

Many key functions performed by the liver depend on the interaction between parenchymal cells and the microenvironment comprised of neighboring cells and extracellular matrix. The biological macromolecules in the matrix, which are dynamically changing, participate in various physiological processes through interactions with cell surface receptors, antigens, and ion channels. We found the rat liver biomatrix scaffold (LBS) prepared from adult rats is more effective in enhancing the function of hepatic spheroids than those derived from newborn or senile rats. Combined with matrisome and bioinformatics analyses, we further found that the glycoproteins, fibronectin and fibrinogen may have special potential for improving hepatocyte function. Human primary hepatocyte organoids and HepaRG spheroids showed more mature hepatocyte phenotype after adding fibronectin and fibrinogen to the culture system. During the cultivation of hepatic spheroids, fibrinogen resulted in an increase in cell-cell junction by promoting cell aggregation and helping fibronectin to assemble on cell surface, which resulted in activation of Wnt/β-catenin pathway. Fibronectin-integrin αVβ1-Wnt/β-catenin may be the axis of signal transduction in parenchymal cell microenvironment. Importantly, fibrinogen enhances the signal transduction. These results suggest that the addition of fibronectin and fibrinogen to the 3D culture system is a new strategy for inducing parenchymal cell functional maturation.

The prevalence of nonalcoholic fatty liver disease (NAFLD), a common cause of chronic liver disease, continues to increase in parallel with that of obesity. Currently, there are no preclinical models to study its complex pathogenesis nor to assess candidate therapies. We have established a tissue-engineered (TE) liver by seeding cells into liver-derived matrix scaffolds and then perfusing the scaffolds with a medium that dynamically provides requisite nutrients, vitamins, minerals, and hormones. Liver-specific biomatrix scaffolds, comprised of almost all of the liver's known extracellular matrix (ECM) components and matrix-bound soluble signals (e.g., growth factors/cytokines), were recellularized with human hepatic cell line HepG2 and perfused with a complete medium enabling the cells to form functioning liver tissue. By perfusing the system with medium with a high fat content, the cells established a TE fatty (TEF) liver model paralleling that of livers in NAFLD patients. The high fat medium containing 500 μM of free fatty acids (FFAs) (oleic acid:palmitic acid = 2:1) caused the TEF livers to accumulate 2-times more fat than those in the control medium over an 8 day culture period and significantly influenced the capacity of fatty acid synthesis and metabolism. PDK4, CYP2E1, and CYP7A1 genes associated with NAFLD and other liver diseases were all up-regulated, and the metabolic activity of CYP3A4 was significantly impaired. Excess FFAs also induced alterations in transporters and key enzymes in the lipid biosynthesis pathway. The TEF liver was used to test if an antisteatotic drug, Metformin, used in patients with NAFLD, would be able to provide effects paralleling those observed in some patients. Metformin treatment of the TEF liver model caused reduced cellular triglycerides, activated AMPK molecule, inhibited mTORC1 signaling pathway, which thus affected the synthesis and metabolism of FFAs. Overall, the TEF liver offers a stable and reproducible model to study the NAFLD development process and antisteatotic drug effects.

Sweat glands perform a vital thermoregulatory function in mammals. Like other skin components, they originate from epidermal progenitors. However, they have low regenerative potential in response to injury. We have established a sweat gland culture and expansion method using 3D organoids cultures. The epithelial cells derived from sweat glands in dermis of adult mouse paw pads were embedded into Matrigel and formed sweat gland organoids (SGOs). These organoids maintained remarkable stem cell features and demonstrated differentiation capacity to give rise to either sweat gland cells (SGCs) or epidermal cells. Moreover, the bipotent SGO-derived cells could be induced into stratified epidermis structures at the air−liquid interface culture in a medium tailored for skin epidermal cells in vitro. The SGCs embedded in Matrigel tailored for sweat glands formed epithelial organoids, which expressed sweat-gland-specific markers, such as cytokeratin (CK) 18 and CK19, aquaporin (AQP) 5 and αATP. More importantly, they had potential of regeneration of epidermis and sweat gland when they were transplanted into the mouse back wound and claw pad with sweat gland injury, respectively. In summary, we established and optimized culture conditions for effective generation of mouse SGOs. These cells are candidates to restore impaired sweat gland tissue as well as to improve cutaneous skin regeneration.

The 16S-23S rRNA gene internal transcribed spacer (ITS) regions of Klebsiella spp., including Klebsiella pneumoniae subsp. pneumoniae, Klebsiella pneumoniae subsp. ozaenae, Klebsiella pneumoniae subsp. rhinoscleromatis, Klebsiella oxytoca, Klebsiella planticola, Klebsiella terrigena , and Klebsiella ornithinolytica , were characterized, and the feasibility of using ITS sequences to discriminate Klebsiella species and subspecies was explored. A total of 336 ITS sequences from 21 representative strains and 11 clinical isolates of Klebsiella were sequenced and analyzed. Three distinct ITS types—ITS none (without tRNA genes), ITS glu [with a tRNA Glu (UUC) gene], and ITS ile+ala [with tRNA Ile (GAU) and tRNA Ala (UGC) genes]—were detected in all species except for K. pneumoniae subsp. rhinoscleromatis , which has only ITS glu and ITS ile+ala . The presence of ITS none in Enterobacteriaceae had never been reported before. Both the length and the sequence of each ITS type are highly conserved within the species, with identity levels from 0.961 to 1.000 for ITS none , from 0.967 to 1.000 for ITS glu , and from 0.968 to 1.000 for ITS ile+ala . Interspecies sequence identities range from 0.775 to 0.989 for ITS none , from 0.798 to 0.997 for ITS glu , and from 0.712 to 0.985 for ITS ile+ala . Regions with significant interspecies variations but low intraspecies polymorphisms were identified; these may be targeted in the design of probes for the identification of Klebsiella to the species level. Phylogenetic analysis based on ITS regions reveals the relationships among Klebsiella species similarly to that based on 16S rRNA genes.

We used Inter-Simple Sequence Repeats (ISSR) markers to reveal the genetic diversity of 95 Fusarium oxysporum f. sp. cubense ( FOC ) isolates from banana in China, for the rational control of the disease.Eight primers were chosen for analyzing FOC isolates to study their genetic diversity by ISSR-PCR. All isolates were clustered using Unweighted Pair-Group Method with Arithmetic means (UPGMA) analysis by NTSYSpc v2.10e software.A total of 52 sites were generated, among them 92.3% were polymorphic. Genetic distance was 0.57 to 1.00 based on the Nei's standard. Isolates were grouped into six distinct clusters (A, B, C, D, E and F) based on ISSR analysis using a genetic distance threshold of 0.68, the proportion of 51.06%, 39.58%, 5.20%, 2.08%, 1.04%, and 1.04%, respectively.There were high levels of genetic variation among the FOC isolates, and the ISSR clustering groups had obvious correlation with hosts and races of the pathogen.