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During extraction of coalbed methane well, the most used method is pumping unit discharge and extraction system. The conventional mono-barrel pump is usually used as the discharge and extraction pump; the main problem of this pump is that pump is stuck by coal dust with standing valve and traveling valve are also stuck by coal dust, leading to frequent operation of the system and severely affecting the production efficiency of coalbed methane. In order to effectively solve this problem, a set of string integrating discharge, extraction and bailing of coal dust has been developed, which uses new coal dust-proof pump and basket settling pipe, making it possible to integrate discharge, extraction and sand bailing in coalbed methane wells. The new coaldust-proof pump utilizes long plunger structure with highly standing valve and large-diameter travelling valve, which cannot only effectively prevent coaldust from sticking the standing valve and travelling valve, but also effectively prevent coaldust from entering pump barrel and causing stuck pump. The coaldust deposited during discharge and extraction goes into the basket sand setting pipe, which will be removed together with coaldust deposited in the sand setting pipe during pump inspection, diminishing the work of bailing coaldust and saving the cost. Field application shows that the pipe string integrating coalbed methane discharge, extraction and coaldust bailing by vertical well can meet the site requirement, extend the pump inspection cycle and has good promotion prospect. [ABSTRACT FROM AUTHOR]

[This corrects the article on p. 3517 in vol. 9, PMID: 28804568.].

The clinical utility of Traditional Chinese Medicine (TCM) herbs/roots extracts in osteoporosis (OP) and osteoarthritis (OA) has been described in multiple reports, but there have been few studies of TCM for preventing bone loss and cartilage degradation simultaneously. Six-month-old female Sprague-Dawley rats each were subjected to ovariectomized (OVX) or sham surgery and treated orally once daily with herbal extracts or vehicle. Body weight was recorded weekly, and blood samples were collected from fasting animals at different time points. Biochemical markers of bone resorption and cartilage degradation were analyzed. Changes in bone mineral density and calcium content were determined in the femoral center and femoral telocentric end of rats. Out of 56 TCM herbs/roots extracts, only kudzu root demonstrated consistent joint protective effects. OVX resulted in a marked increase in bone resorption and cartilage degradation, which could be significantly reversed by kudzu after three weeks of treatment. Compared to vehicle, kudzu induced a significant increase in bone mineral density in the femoral center and femoral telocentric end, and calcium content. The results show that kudzu exerts direct effects on articular cartilage in the OVX rat and can effectively prevent the acceleration of cartilage degradation induced by ovariectomy. Moreover, kudzu has demonstrated positive effects on metabolic health (cause a weight reduction) and may represent a possible treatment for OP and OA with high body mass index. Further studies are needed to investigate the potential effects of kudzu root in postmenopausal women., Competing Interests: None.

Aim: The present study describes the assessment of true formation of type III collagen in different pathologies using a neo-epitope specific competitive Enzyme-linked immunosorbent assay (ELISA) towards the N-terminal propeptide of type III collagen (PRO-C3)., Methods: The monoclonal antibody was raised against the N-protease mediated cleavage site of the N-terminal propeptide of type III collagen and a competitive ELISA was developed using the selected antibody. The assay was evaluated in relation to neo-epitope specificity, technical performance, and as a marker for liver fibrosis and muscle mass using the rat carbon tetrachloride (CCl4) model and a study of immobilization induced muscle loss in humans, respectively., Results: The ELISA was neo-epitope specific, technically stable and can be assessed in serum and plasma samples. In the CCl4 liver fibrosis model it was observed that serum PRO-C3 were significantly elevated in rats with liver fibrosis as seen by histology (56% elevated in the highest quartile of total hepatic collagen compared to control rats, p<0.001) and correlated significantly to total hepatic collagen in the diseased rats (r=0.46, p<0.01) and not in control rats, suggesting the pathological origin of the epitope. Human plasma PRO-C3 correlated significantly to muscle mass at baseline (R(2)=0.44, p=0.036)., Conclusion: The developed neo-epitope specific serum ELISA for type III procollagen (PRO-C3) reflects true formation as it is specific for the propeptide cleaved off the intact collagen molecule. In a clinical and in a rodent study we showed that this marker was highly related to liver fibrosis and muscle mass.

Extracellular matrix remodelling is a prerequisite for plaque rupture in atherosclerotic lesion. Versican, an extracellular matrix proteoglycan present in normal and atherosclerotic arteries is a substrate for matrix metalloproteinases (MMPs) present in macrophage rich areas. The aim of the current study was to develop an immunoassay to detect a specific MMP-12 derived versican degradation fragment (VCANM) and assess its potential as a biomarker for extracellular matrix remodelling in atherosclerosis. A mouse monoclonal antibody raised against VCANM was used for the development of a competitive ELISA for detection of the fragment in plasma. VCANM was measured in plasma of patients with different levels of heart diseases. Patients experiencing I) acute coronary syndrome, II) stable ischemic heart disease and III) demonstrating high levels of coronary calcium deposits had significantly higher plasma levels of VCANM compared to a control group of individuals with no detectable coronary calcium deposits. VCANM was also detected by immunohistochemistry in coronary artery sections of patients with different degrees of atherosclerosis. VCANM ability to separate patients with atherosclerotic diseases from healthy individuals suggested VCANM as a potential biomarker for the pathological arterial matrix remodelling associated with atherosclerosis.

The alpha1,2-fucosyltransferase family (alpha1,2FT) is the largest family of glycosyltransferases in the genome of the free-living nematode Caenorhabditis elegans, and early evidence suggests that each member may have a unique activity. Here we describe a C. elegans gene (designated CE2FT-2) encoding an alpha1,2FT that has the potential to generate the sequence Fucalpha1-2Galbeta1-3GalNAcalpha-R, which is the H-type 3 blood group structure. The CE2FT-2 cDNA encodes a putative transmembrane protein that shows approximately 42% amino acid identity to a previously cloned C. elegans alpha1,2FT (termed CE2FT-1), but has a very low identity ( approximately 16-20%) to alpha1,2FT sequences in humans, rabbits, and mice. A recombinant form of CE2FT-2 expressed in human 293T cells has a high alpha1,2FT activity toward Galbeta1-3GalNAcalpha-O-pNP, but unexpectedly, the enzyme is inactive toward the acceptor Galbeta-O-phenyl. Thus, CE2FT-2 differs from all other alpha1,2FTs previously described from animals that all utilize Galbeta-O-phenyl. CE2FT-2 is expressed at all stages of worm development, but remarkably, promoter analysis of the CE2FT-2 gene using green fluorescent protein reporter constructs indicates that the CE2FT-2 is expressed exclusively in pharyngeal cells of the worm from embryo to an adult stage. Because pharyngeal cells are known to secrete their glycoconjugates to the nematode surface, these results may indicate that products of CE2FT-2 contribute to interactions of the nematode with its environment or are used as ligands for bacterial attachment. These findings, along with those on other alpha1,2FTs in C. elegans, suggest that each alpha1,2FT in this organism may have a unique acceptor specificity, expression pattern, and biological function.