Rolipram plays an anti-fibrotic effect in ligamentum flavum fibroblasts by inhibiting the activation of ERK1/2.

BACKGROUND: Fibrosis is an important factor and process of ligamentum flavum hypertrophy. The expression of phosphodiesterase family (PDE) is related to inflammation and fibrosis. This article studied the expression of PDE in hypertrophic ligamentum flavum fibroblasts and investigated whether inhibition of PDE4 activity can play an anti-fibrotic effect. METHODS: Samples of clinical hypertrophic ligamentum flavum were collected and patients with lumbar disc herniations as a control group. The collagenase digestion method is used to separate fibroblasts. qPCR is used to detect the expression of PDE subtypes, type I collagen (Col I), type III collagen (Col III), fibronectin (FN1) and transforming growth factor ß1 (TGF-ß1). Recombinant TGF-ß1 was used to stimulate fibroblasts to make a fibrotic cell model and treated with Rolipram. The morphology of the cells treated with drugs was observed by Sirius Red staining. Scratch the cells to observe their migration and proliferation. WB detects the expression of the above-mentioned multiple fibrotic proteins after drug treatment. Finally, combined with a variety of signaling pathway drugs, the signaling mechanism was studied. RESULTS: Multiple PDE subtypes were expressed in ligamentum flavum fibroblasts. The expression of PDE4A and 4B was significantly up-regulated in the hypertrophic group. Using Rolipram to inhibit PDE4 activity, the expression of Col I and TGF-ß1 in the hypertrophic group was inhibited. Col I recovered to the level of the control group. TGF-ß1 was significantly inhibited, which was lower than the control group. Recombinant TGF-ß1 stimulated fibroblasts to increase the expression of Col I/III, FN1 and TGF-ß1, which was blocked by Rolipram. Rolipram restored the increased expression of p-ERK1/2 stimulated by TGF-ß1. CONCLUSION: The expressions of PDE4A and 4B in the hypertrophic ligamentum flavum are increased, suggesting that it is related to the hypertrophy of the ligamentum flavum. Rolipram has a good anti-fibrosis effect after inhibiting the activity of PDE4. This is related to blocking the function of TGF-ß1, specifically by restoring normal ERK1/2 signal.

HIF-1α-Mediated miR-623 Regulates Apoptosis and Inflammatory Responses of Nucleus Pulposus Induced by Oxidative Stress via Targeting TXNIP.

Excessive apoptosis and inflammatory responses of nucleus pulposus (NP) cells induced by oxidative stress contribute to intervertebral disc degeneration (IVDD). Though some microRNAs are associated with IVDD, the specific microRNA that can mediate apoptotic and inflammatory responses of NP cells induced by oxidative stress synchronously still needs further identification. Here, we find that microRNA-623 (miR-623) is downregulated in IVDD and its expression is regulated by hypoxia-inducible factor-1α (HIF-1α) under oxidative stress conditions. Mechanistically, HIF-1α is observed to promote miR-623 expression by directly binding to its promoter region (-1,994/-1,987 bp). Functionally, miR-623 is found to work as an intermediator in alleviating apoptosis and inflammatory responses of NP cells induced by oxidative stress via regulating thioredoxin-interacting protein (TXNIP) expression by directly targeting its 3'-untranslated region (3'-UTR). Thus, on elucidating the expression and functional mechanisms of miR-623, our study suggests that miR-623 can be a valuable therapeutic target for treating oxidative stress-induced IVDD.

[Determination of 7 penicilins and penicilloic acids in milk products by high performance liquid chromatography-tandem mass spectrometry].

OBJECTIVE: A high performance liquid chromatography-tandem mass spectrometric method was established for determination of 7 penicilins (cloxacillin, nafcillin, oxacillin, penicillin V, amoxicillin, penicillin G, ampicillin) and their penicilloic acids (cloxacilloic acid, nafcilloic acid, oxacilloic acid, penicilloic acid V, amoxicilloic acid, penicilloic acid G and ampicilloic acid) in milk products. And the 7 penicilins and penicilloic acids in milk products were surveyed. METHODS: The 7 penicilins and penicilloic acids in milk products were extracted by water in super-sonic instrument , precipitated proteins by acetonitrile and degreased fat by n-hexane with liquid-liquid extraction, then the purified solution was concentrated by nitrogen, dissolved with acetonitrile-water (10 + 90, V/V) and cleaned by 0.22 µm millipore filter. The filtrate was detected by high performance liquid chromatography-tandem mass spectrometry, identified by electrospray ionization (ESI) in positive mode using multiple reaction monitoring, and quantified with external standards. RESULTS: The calibration curves of 7 penicilins and penicilloic acids showed good linearity in the range of 1.0-200 µg/kg with correlation coefficients were above 0.9992. The detection limits of the method were from 0.03 µg/kg to 0.15 µg/kg. The recoveries of three spiking levels ranged from 80.0% to 110.0%, and RSDs of 7.06% or less were obtained. CONCLUSION: The method for determination of 7 penicilins and penicilloic acids in milk products by HPLC-MS/MS was of operation convenience, less interference from impurities and good accuracy, which could meet the requirements for the determination of 7 penicilins and penicilloic acids residues in milk products.

Basic occupational health services in Baoan, China.

OBJECTIVES: The aim of the study was to develop a model of basic occupational health services (BOHS) in Baoan, which could provide occupational health services (OHS) universally for workers and control occupational hazards. METHODS: Steps involved in the BOHS strategy included construction of the BOHS system, capacity building, health training and education, surveillance of workplaces and the health of workers, risk assessment, control and evaluation processes. RESULTS: This model provided BOHS to employees universally, especially migrant workers in small- and medium-sized enterprises (SMEs) who had been underserved. It expanded the coverage of OHS and improved their content. The knowledge and recognition rate of occupational diseases, the coverage rates of working places and workers rose significantly after three years development. Furthermore, BOHS were cost-effective and accepted by both employers and employees. CONCLUSIONS: Our experience suggests that a BOHS strategy might be a feasible and effective way of protecting the health of workers confronted with occupational hazards.

[A follow-up study on dietary factors of kidney stones in Bao'an district, Shenzhen City].

OBJECTIVE: To evaluate the major dietary factors of kidney stones in Bao'an District of Shenzhen City and provide a scientific base for further effective prevention of kidney stones. METHODS: Following the process of stratified cluster random sampling in Bao'an district, a cross-sectional study (July-Aug, 2000) was conducted for collecting the base-line data on kidney stones from a population of permanent residents who were over 15 years old, exclusive of those who had had kidney stones or could not correctly respond to the questionnaire review. Then, a follow-up survey (July-Sept, 2002) for incident kidney stone cases was carried out among those residents. The methods for measurement included questionnaire and face-to-face interview, clinical examination and abdominal ultrasonography. All the investigators and interviewers were trained for the field work. And the data processing, dataset and analyses were performed using Visual-Fox 6.0 and SAS 6.12. The risk factors of kidney stoned were comprehensively analyzed for dietary, life style, and family history of stones. The statistical analyses included case-control comparison, factor analysis, correlation analysis, cluster analysis and logistic regression. RESULTS: There were 305 kidney stones patients among 4552 follow-up members, the cumulative incidence of 2 years was 6.92%. The kidney stones were associated with the factors: menopause, RR=2.433; family history of stones, RR=1.544; sea foods, the RR (5-7 times/week vs < or = 1-2 times/month) was 9.032; fruits, the RR (< or = 1-2 times/month vs > or = 1-2 times/week) was 2. 249; sweet foods, the RR (5-7 times/week vs 1-2 times/week) was 2. 568; bean and bean products, the RR (5-7 times/week and < or = 1-2 times/month vs 1-2 times/week) was 2.184 and 1.689. CONCLUSION: Changing the inappropriate habitual eating patterns and generalizing the use of proportioning dietary should be the main measures to prevent kidney stones.

[A 1:2 matched case-control study on congenital external malformation during perinatal period].

OBJECTIVE: To investigate the risk factors for congenital external malformation. METHODS: A 1:2 matched case-control study was conducted with 52 cases of congenital external malformation during perinantal period collected from surveillance in Baoan District of Shenzhen City from January to June in 2000. RESULTS: Simple and multiple conditional logistic regression analysis showed that the major risk factors for congenital external malformations during perinatal period were preterm labor (beta(k) = 1.4171, s(theta, beta(kappa)) = 0.4601, OR = 4.115), adverse mental stimulus (beta(kappa) = 2.1870, s(theta beta(kappa)) = 0.7873, OR = 8.909), taking medicine (beta(k) = 1.9178, s(theta beta(kappa)) = 0.8072, OR = 6.808) and exposure to hazardous chemicals during early pregnancy (beta(k) = 0.9602, s(theta beta(kappa)) = 0.4262, OR = 2.612). CONCLUSIONS: Congenital external malformation during perinatal period was caused by multiple risk factors and results of the study showed that environmental and mental factors were in obvious connection with its occurrence.