Developmental changes in sulphation of chondroitin sulphate proteoglycan during myogenesis of human muscle cultures

The synthesis and secretion of chondroitin sulphate proteoglycan (CSPG) was examined in human muscle cultures during myogenesis prior to myoblast fusion and following myotube formation. Results from this study demonstrate that the major CSPG secreted into the medium had a Kav of 0.15 on Sephacryl 500 (exclusion limit of 10(7) Da) and contained predominantly unsulphated residues in mononucleated cell cultures but these became increasingly sulphated in postfusion cultures. Fibroblasts synthesised small amounts of a smaller molecular weight CSPG indicating that the Kav 0.15 proteoglycan is solely synthesised by cells of the myogenic lineage. These findings illustrate that sulphation of CSPG is developmentally regulated during myogenesis of human muscle cells grown under differentiating conditions.     

Surrogate modeling of articular cartilage degradation to understand the synergistic role of MMP-1 and MMP-9: a case study

Biomechanics and Modeling in Mechanobiology - A characteristic feature of arthritic diseases is cartilage extracellular matrix (ECM) degradation, often orchestrated by the overexpression of matrix...     

Growth and Physiology of Maize (Zea mays L.) in a Nickel-Contaminated Soil and Phytoremediation Efficiency Using EDTA

Journal of Plant Growth Regulation - Nickel (Ni) element is strongly phytotoxic at high concentrations for several plants, but due to its dual behavior and complicated chemistry, it has received...     

Free radical scavenging activity,total phenolic content,total antioxidant status,and total oxidant status of endemic Thermopsis turcica

Thermopsis turcica, endemic to Turkey, is in danger of extinction. Studies on this species are very few due to the fact that it was only discovered in 1983 and grows in a small circumscribed area in Turkey. In this study, free radical scavenging activity, total phenolic content, total oxidant status (TOS), and total antioxidant status (TAS) of methanol (TTM) and acetone (TTA) extracts of T. turcica were measured spectroscopically. Free radical scavenging activity was determined according to the elimination of DPPH radicals and total phenol content was determined by the Folin–Ciocalteu reaction. Total oxidant status (TOS) and total antioxidant status (TAS) were measured with commercially available kits. Methanol and acetone extracts of T. turcica were found to have a specific radical scavenging effect. This effect was found to be related to the total phenolic content of the extracts. Since the TTA had a higher phenolic content than the methanol extract, it had a stronger radical scavenging effect. In addition, the total antioxidant capacity of the methanol extract was observed to be higher than that of its acetone counterpart. As a result, due to its antioxidative properties, T. turcica is thought to be a natural source of antioxidants.     

Isolation and Molecular Identification of Fungi with Magnesite Enrichment Potential from KÜMAŞ Quarries in Turkey

Abstract

Magnesite is an important raw material used in various industrial applications, especially the production of high-temperature resistant materials. Due to its high reactant nature, magnesite ore is not found in pure form and it contains a great variety of pollutants such as calcium compounds, which restrict its use when exceeding 1% of the ore. Thus, the development of efficient strategies for the removal of pollutants remains a crucial step for magnesite utilization. In this regard, our present work was conducted to isolate and identify active fungal strains that remove calcium pollutants without changing the main magnesium content of the ore. For this aim, magnesite ore samples were collected from two quarries (Turanoca?? and Ortaocak) of KÜMA? Magnesite Inc. and fungal isolation studies were done by using the ore’s flora. Active isolates were chosen according to their CaCO₃ and MgCO₃ dissolving capabilities and identified by using conventional light microscopy and molecular characterization techniques. 71 fungal isolates were obtained from the isolation step and 14 of them were chosen as active isolates that solve calcium compounds while not affecting the magnesium component. The data of the microscopic examination and 18S rDNA gene sequence analysis showed that 14 active strains with magnesite enrichment potential grouped in Aspergillus alliaceus (3), Aspergillus flavus (2), Aspergillus leporis (1), Aspergillus nomius (1), Fusarium tricinctum (2), Penicillium chrysogenum (1) and Penicillium sp. (4).     

Effect of collagenase–gelatinase ratio on the mechanical properties of a collagen fibril: a combined Monte Carlo–molecular dynamics study

Loading in cartilage is supported primarily by fibrillar collagen, and damage will impair the function of the tissue, leading to pathologies such as osteoarthritis. Damage is initiated by two types of matrix metalloproteinases, collagenase and gelatinase, that cleave and denature the collagen fibrils in the tissue. Experimental and modeling studies have revealed insights into the individual contributions of these two types of MMPs, as well as the mechanical response of intact fibrils and fibrils that have experienced random surface degradation. However, no research has comprehensively examined the combined influences of collagenases and gelatinases on collagen degradation nor studied the mechanical consequences of biological degradation of collagen fibrils. Such preclinical examinations are required to gain insights into understanding, treating, and preventing degradation-related cartilage pathology. To develop these insights, we use sequential Monte Carlo and molecular dynamics simulations to probe the effect of enzymatic degradation on the structure and mechanics of a single collagen fibril. We find that the mechanical response depends on the ratio of collagenase to gelatinase—not just the amount of lost fibril mass—and we provide a possible mechanism underlying this phenomenon. Overall, by characterizing the combined influences of collagenases and gelatinases on fibril degradation and mechanics at the preclinical research stage, we gain insights that may facilitate the development of targeted interventions to prevent the damage and loss of mechanical integrity that can lead to cartilage pathology.

     

Systematics,genetics, and biogeography of intertidal mites (Acari,Oribatida) from the Andaman Sea and Strait of Malacca

This study demonstrates for the first time the presence of marine‐associated mites in the Andaman Sea and Strait of Malacca and reveals a relatively high diversity of these taxa with six species from two different families: Selenoribatidae and Fortuyniidae. Indopacifica, a new genus of Selenoribatidae, is described from Thailand and Malaysia, with two new species, Indopacifica pantai n. sp. and Indopacifica parva n. sp. The genus is characterized by the unique combination of following characters: lacking lamellar ridges, incomplete dorsosejugal suture, fourteen pairs of notogastral setae, and presence of epimeral foveae. A phylogenetic reconstruction based on 18S ribosomal RNA sequences clearly confirms the distinctness of the new genus Indopacifica and places it close to the genus Rhizophobates. The lack of molecular genetic data of possible relatives impedes a clear assessment, and hence, we emphasize the need for further combined approaches using morphological and molecular genetic sequence data. All species show wide distribution areas within this geographic region suggesting that these taxa are good dispersers despite their minute size and wingless body. Molecular genetic data demonstrate recent gene flow between far distant populations of I. pantai n. sp. from the coasts of Thailand and two islands of Malaysia and hence confirm this assumption. The seasonally changing surface currents within this geographic area may favor hydrochorous dispersal and hence genetic exchange. Nevertheless, morphometric data show a slight trend to morphological divergence among the studied populations, whereas this variation is suggested to be a result of genetic drift but also of habitat differences in one population of Alismobates pseudoreticulatus.     

DNA fingerprinting of human isolates of Salmonella enterica serotype Paratyphi B in Malaysia

AIMS: DNA fingerprinting of Salmonella enterica serotype Paratyphi B isolated in Malaysia during 1982-83, 1992 and 1996-2002 was carried out by pulsed-field gel electrophoresis (PFGE), antimicrobial susceptibility tests and D-tartrate utilization tests to assess the extent of genetic diversity of these isolates in Malaysia. METHODS AND RESULTS: Eighty-six human isolates and one food isolate of Salm. Paratyphi B were analysed by PFGE, antimicrobial susceptibility tests and D-tartrate utilization tests. Sixty-five strains were D-tartrate-negative (dT-) while 22 strains were D-tartrate-positive (dT+). Thirty-seven per cent of the Salm. Paratyphi B strains were resistant to one or more antimicrobial agents. PFGE analysis clearly distinguished the dT- and dT+ strains into two clusters based on the unweighted pair group average method (UPGMA). Twenty-two XbaI-pulsotypes were observed among the 65 dT- strains while 17 XbaI-pulsotypes were observed among the 22 isolates of Salm. Paratyphi B dT+. CONCLUSIONS: The present study showed that PFGE was very discriminative with 33.7% of the strains yielding distinct fingerprints. Paratyphoid fever in Malaysia is probably caused by one predominant, endemic clone of Salm. Paratyphi B dT- with various subtypes. There was no association between the pulsotypes and the severity of the disease indicating that the severity of the disease is probably multifactorial. SIGNIFICANCE AND IMPACT OF THE STUDY: The findings of the present study verify the usefulness of PFGE in characterizing strains of Salm. Paratyphi B. This is the first report on the application of PFGE on a large collection of Salm. Paratyphi B in Malaysia.