Carboxy-terminal Procollagen Research Articles

Effect of minimally invasive anterior lateral approach for total hip arthroplasty on serum type I collagen propeptide, tartrate-resistant acid phosphatase 5b and hip joint function in patients with femoral neck fracture

To analyze the level of serum N-terminal propeptide of type I precollagen (PINP) and tartrate resistant acid phosphatase 5b(TRACP-5b) in patients with femoral neck fracture(FNF) after minimally invasive anterior lateral approach with total hip arthroplasty and the effects of hip function. From September 2016 to May 2017, 98 cases of femoral neck fracture were divided into control group and observation group, 49 cases in each group. There were 49 patients in control group, including 30 males and 19 females, ranging in age from 63 to 72 years old, who underwent minimally invasive anterolateral total hip arthroplasty. There were 49 patients in observation group, including 29 males and 20 females, ranging in age from 62 to 73 years old, who underwent minimally invasive anterolateral total hip arthroplasty. The perioperative conditions(operation time, bleeding volume, incision length, hospitalization time), bone metabolism indexes including PINP, TRACP-5b, fibroblast growth factor(FGF), bone gla-protein(BGP), propetide carboxy-terminal procollagen (PICP), bone-specific alkaline phosphatase(BAP), and pain mediators such as prostaglandin E2 (PGE2) and 5-hydroxytrytamine (5-HT) levels were compared between the two groups. The hip joint function and complications were evaluated. The operation time of the observation group was longer than that of the control group(P<0.05); there was no significant difference in bleeding volume, incision length and hospitalization time between two groups(P>0.05). PINP, fibroblast growth factor, BGP, PICP and BAP in observation group were higher than those in control group 1 month after operation, and TRACP-5b was lower than those in control group(P<0.05); PGE2 and 5-HT in observation group 1 month after operation were lower than those before operation, and lower than those in control group(P<0.05). The excellent and good rate of hip function in observation group was higher than that in control group (P<0.05), and the incidence of complications was not significantly different from that in the control group (P>0.05). Minimally invasive anterolateral approach total hip arthroplasty is safe and reliable, and can improve hip function, improve bone metabolism, promote fracture healing, alleviate pain in patients with femoral neck fracture, which is worthy of promotion.

KOSTNYY METABOLIZM I POTERYa KOSTNOY TKANI V OTDALENNYE SROKI POSLE ALLOTRANSPLANTATsII TRUPNOY POChKI (ATP) (ODNOMOMENTNOE ISSLEDOVANIE)

Bone turnover markers [osteocalcin (OC), carboxyterminal procollagen I propeptide (PICP), bone alkaline phosphatase (bALP), deoxypyridinoline (DPD), β -crosslaps (CTX), bone acid phosphatase (bACP), parathyroid hormone (PTH)], day calcium excretion (uCaV) and lumbar and hip bone mineral content (BMC) were determined in 195 patients [78 women and 74 men with intact renal function as well as 11 women and 31 men with renal failure (RF)] 40±33 months following KT. KT recipients received triple immunosuppressive therapy (CysA, prednisolone and azathioprine). All groups showed bone remodeling dissociation namely bone resorption increase (high CTX, DPD, bACP) and bone formation retard (mild enhanced level OC, normal or low bALP) in association with high PTH, decreased uCaV and BMC levels. High bone turnover and low uCaV were much more high degree in RF. Vertebral and femur BMC decrease was mild (osteopenia) and only men with RF revealed peripheral osteoporosis. Hyperparathyroidism was associated with decreased transplant function and was main predictor of high bone turnover and bone loss after KT.

Effect of cyclical stretch on matrix synthesis of human patellar tendon cells

The significance of mobilization and loading for healing ligaments and tendons is generally accepted today. Local deformation of cells thereby represents the key stimulus for the cellular response. Less is known, however, about the effects of cyclic strain on the cellular and molecular level. The aim of the in vitro investigation was to determine the effect of cyclic mechanical strain on collagen type I and III and on fibronectin formation in human patellar tendon derived fibroblasts. Human patellar tendon derived fibroblasts from 5 donors (mean age 29.2 years) were cultured under standard conditions. Monolayers of subconfluently grown 3rd passage cells were stretched in rectangular silicone dishes with cyclic movement along their longitudinal axes. Cyclic strain (5%, 1 Hz) was applied for 30 min and 60 min, respectively. Carboxyterminal procollagen type I propeptide (P-I-CP) and aminoterminal procollagen type III propeptide (P-III-NP) release was measured by a radio-immunoassay 6 h and 12 h after stretching. The release of fibronectin was measured by nephelometry following immunoreaction with a specific antiserum. Cells from each donor without any cyclic stretching served as controls. Compared with the controls, only cyclic stretching for 60 min resulted in a significantly increased release of P-I-CP and fibronectin after 6 h. The release of P-III-NP was significantly increased 12 h after 30 min of cyclic stretching as well as 6 h and 12 h after 60 min of cyclic stretching, respectively. We conclude that cyclic stretching causes a time-dependent, differential regulation of formation of fibronectin and collagen type I and III. This may effect the quality and thus the mechanical properties of healing tendon and ligament tissues. In order to improve current treatment protocols and to enlarge our knowledge of tissue healing, it is necessary to understand the cellular response to cyclic strain.

Diagnostic value of connective tissue metabolites in Schistosoma mansoni related liver disease

Reliable non-invasive markers of hepatosplenic involvement in schistosomiasis are needed for determination of morbidity levels in endemic populations and for diagnosis and follow-up of affected individuals. Serum levels of connective tissue metabolites have been investigated as fibrosis markers in various hepatic disorders, but their accuracy in the detection of hepatosplenic schistosomiasis under endemic conditions has not been fully elucidated. 206 adult inhabitants of a Tanzanian village highly endemic for schistosomiasis mansoni (prevalence 88%) underwent clinical, parasitological and sonographic work-up; sera were tested for aminoterminal procollagen III-peptide (PIIIP), carboxyterminal procollagen IV peptide (NC1) and laminin. Connective tissue marker levels did not correlate with the presence or intensity of infection. NC1 levels were significantly correlated with periportal liver fibrosis ( P<0.001), splenomegaly ( P<0.002), portal vein dilatation ( P<0.004) and the presence of portosystemic collaterals ( P<0.001); for PIIIP and laminin, none of the respective relationships was significant. Due to wide overlap of NC1 levels between individuals with normal sonography findings and those with advanced periportal fibrosis and portal hypertension, the sensitivity and positive predictive value of this markers to detect these individuals were low (<40%), although specificity and overall accuracy in the given setting were good (80–90%). It is concluded that PIIIP and laminin are not useful as diagnostic serum markers of hepatosplenic schistosomiasis at the community level; NC1 was significantly related to various indices of hepatosplenic involvement, but its low sensitivity precludes its use as a screening tool under endemic conditions.

Toward the biochemical assessment of myocardial fibrosis in hypertensive patients

The serum concentrations of amino-terminal procollagen type III and carboxy-terminal procollagen type I-derived peptides, which have been proposed as useful markers of the tissue synthesis of collagen types III and type I, respectively, were abnormally increased in patients with essential hypertension and became normal after angiotensin-converting enzyme (ACE) inhibition. An association was found between baseline serum concentrations of these peptides and left ventricular hypertrophy, diastolic dysfunction, and ventricular arrhythmias in hypertensive patients. On the other hand, increased serum concentration of the carboxy-terminal procollagen type I-derived peptide was found in spontaneously hypertensive rats compared with normotensive Wistar-Kyoto control rats. An association was found between the serum concentration of this peptide and the extent of myocardial fibrosis and the hydroxyproline concentration in the left ventricle of spontaneously hypertensive rats. It is proposed that procollagen-derived peptides in serum may be markers of exaggerated collagen tissue synthesis involved in hypertensive myocardial fibrosis.

Synthesis of collagen by chick calvaria in the presence of 2,2'-bipyridyl. Lack of the aminoterminal extension peptides.

A precursor of type I collagen was accumulated when cranial bones from embryonic chicken were cultured in vitro in the presence of 2,2'-bipyridyl. While biochemical studies demonstrate that the precursor was present as a covalently linked trimer, evaluation of electron micrographs of segment-long-spacing aggregates show that the molecules of this precursor have an extension at the carboxy terminus only. These data provide further evidence that the inter-chain disulfide bonds in procollagen are located at the carboxy-terminal extension, and secondly, that 2,2'-bipyridyl does not interfere with a normal cleavage of procollagen peptides at the amino terminus, but inhibits the cleavage of the carboxy-terminal procollagen peptides.