The Impact of Damage Accumulation on the Kinetics of Network Strength Recovery for a Physical Polymer Gel Subjected to Shear Deformation

Shear rheophysical experiments were used to quantify the kinetics of strength recovery of model thermoreversible polymer gels that were fractured and ultimately sheared to different total magnitudes of strain (700 and 4000%) before resting for set periods of time. Relationships between the amount of strength recovered and the normalized ratio of resting times to characteristic relaxation times were developed. It was found that gels displayed fully healed networks within timescales that were 2-3 orders of magnitude greater than the gel’s characteristic relaxation time. Gels deformed to 700% applied strain either healed slower at lower gel concentrations as compared to experiments at larger applied strains due to possible viscous heating or healed faster from incomplete fracture propagation for higher gel concentrations

In Vitro Efficacy of Myxococcus fulvus ANSM068 to Biotransform Aflatoxin B1

Aflatoxin B1 (AFB1) is commonly found in cereals and animal feeds and causes a significant threat to the food industry and animal production. Several microbial isolates with high AFB1 transformation ability have been identified in our previous studies. The aim of this research was to characterize one of those isolates, Myxococcus fulvus ANSM068, and to explore its biotransformation mechanism. The bacterial isolate of M. fulvus ANSM068, isolated from deer feces, was able to transform AFB1 by 80.7% in liquid VY/2 medium after incubation at 30 °C for 72 h. The supernatant of the bacterial culture was more effective in transforming AFB1 as compared to the cells alone and the cell extract. The transformation activity was significantly reduced and eradicated after the culture supernatant was treated with proteinase K, proteinase K plus SDS and heating. Culture conditions, including nitrogen source, initial pH and incubation temperature were evaluated for an optimal AFB1 transformation. Liquid chromatography mass spectrometry (LCMS) analyses showed that AFB1 was transformed to a structurally different compound. Infrared analysis (IR) indicated that the lactone ring on the AFB1 molecule was modified by the culture supernatant. Chromatographies on DEAE-Ion exchange and Sephadex-Molecular sieve and SDS-PAGE electrophoresis were used to determine active components from the culture supernatant, indicating that enzyme(s) were responsible for the AFB1 biotransformation. This is the first report on AFB1 transformation by a strain of myxobacteria through enzymatic reaction(s)

Xenopus as a Model System for the Study of GOLPH2/GP73 Function: Xenopus golph2 Is Required for Pronephros Development

GOLPH2 is a highly conserved protein. It is upregulated in a number of tumors and is being considered as an emerging biomarker for related diseases. However, the function of GOLPH2 remains unknown. The Xenopus model is used to study the function of human proteins. We describe the isolation and characterization of Xenopus golph2, which dimerizes and localizes to the Golgi in a manner similar to human GOLPH2. Xenopus golph2 is expressed in the pronephros during early development. The morpholino-mediated knockdown of golph2 results in edema formation. Additionally, Nephrin expression is enhanced in the glomus, and the expression of pronephric marker genes, such as atp1b1, ClC-K, NKCC2, and NBC1, is diminished in the tubules and duct. Expression patterns of the transcription factors WT1, Pax2, Pax8, Lim1, GATA3, and HNF1β are also examined in the golph2 knockdown embryos, the expression of WT1 is increased in the glomus and expanded laterally in the pronephric region. We conclude that the deletion of golph2 causes an increase in the expression of WT1, which may promote glomus formation and inhibit pronephric tubule differentiation

Genome comparisons indicate recent transfer of wRi-like <i>Wolbachia</i> between sister species <i>Drosophila suzukii</i> and <i>D. subpulchrella</i>

Wolbachia endosymbionts may be acquired by horizontal transfer, by introgression through hybridization between closely related species, or by cladogenic retention during speciation. All three modes of acquisition have been demonstrated, but their relative frequency is largely unknown. Drosophila suzukii and its sister species D. subpulchrella harbor Wolbachia, denoted wSuz and wSpc, very closely related to wRi, identified in California populations of D. simulans. However, these variants differ in their induced phenotypes: wRi causes significant cytoplasmic incompatibility (CI) in D. simulans, but CI has not been detected in D. suzukii or D. subpulchrella. Our draft genomes of wSuz and wSpc contain full-length copies of 703 of the 734 single-copy genes found in wRi. Over these coding sequences, wSuz and wSpc differ by only 0.004% (i.e., 28 of 704,883 bp); they are sisters relative to wRi, from which each differs by 0.014%–0.015%. Using published data from D. melanogaster, Nasonia wasps and Nomada bees to calibrate relative rates of Wolbachia versus host nuclear divergence, we conclude that wSuz and wSpc are too similar—by at least a factor of 100—to be plausible candidates for cladogenic transmission. These three wRi-like Wolbachia, which differ in CI phenotype in their native hosts, have different numbers of orthologs of genes postulated to contribute to CI; and the CI loci differ at several nucleotides that may account for the CI difference. We discuss the general problem of distinguishing alternative modes of Wolbachia acquisition, focusing on the difficulties posed by limited knowledge of variation in absolute and relative rates of molecular evolution for host nuclear genomes, mitochondria, and Wolbachi

Management of liver failure in general intensive care unit

OBJECTIVE: To produce French guidelines on Management of Liver failure in general Intensive Care Unit (ICU). DESIGN: A consensus committee of 23 experts from the French Society of Anesthesiology and Critical Care Medicine (Société française d'anesthésie et de réanimation, SFAR) and the French Association for the Study of the Liver (Association française pour l'étude du foie, AFEF) was convened. A formal conflict-of-interest (COI) policy was developed at the start of the process and enforced throughout. The entire guideline process was conducted independently of any industrial funding. The authors were advised to follow the principles of the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system to guide their assessment of the quality of evidence. The potential drawbacks of making strong recommendations in the presence of low-quality evidence were emphasised. Some recommendations were ungraded. METHODS: Two fields were defined: acute liver failure (ALF) and cirrhotic patients in general ICU. The panel focused on three questions with respect to ALF: (1) Which etiological examinations should be performed to reduce morbidity and mortality? (2) Which specific treatments should be initiated rapidly to reduce morbidity and mortality? (3) Which symptomatic treatment should be initiated rapidly to reduce morbidity and mortality? Seven questions concerning cirrhotic patients were addressed: (1) Which criteria should be used to guide ICU admission of cirrhotic patients in order to improve their prognosis? (2) Which specific management of kidney injury should be implemented to reduce morbidity and mortality in cirrhotic ICU patients? (3) Which specific measures to manage sepsis in order to reduce morbidity and mortality in cirrhotic ICU patients? (4) In which circumstances, human serum albumin should be administered to reduce morbidity and mortality in cirrhotic ICU patients? (5) How should digestive haemorrhage be treated in order to reduce morbidity and mortality in cirrhotic ICU patients? (6) How should haemostasis be managed in order to reduce morbidity and mortality in cirrhotic ICU patients? And (7) When should advice be obtained from an expert centre in order to reduce morbidity and mortality in cirrhotic ICU patients? Population, intervention, comparison and outcome (PICO) issues were reviewed and updated as required, and evidence profiles were generated. An analysis of the literature and recommendations was then performed in accordance with the GRADE® methodology. RESULTS: The SFAR/AFEF Guidelines panel produced 18 statements on liver failure in general ICU. After two rounds of debate and various amendments, a strong agreement was reached on 100% of the recommendations: six had a high level of evidence (Grade 1 ±), seven had a low level of evidence (Grade 2 ±) and six were expert judgments. Finally, no recommendation was provided with respect to one question. CONCLUSIONS: Substantial agreement exists among experts regarding numerous strong recommendations on the optimum care of patients with liver failure in general ICU

The Cost of Cache-Oblivious Searching

info:eu-repo/semantics/publishe