[Evaluation of therapeutic efficacy of arthroplasty with Swanson prosthesis in the surgical treatment of 2-5 metatarsophalangeal joint diseases].

OBJECTIVE: Metatarsophalangeal joint is an important joint for daily weight-bearing walking. Osteoarthritis, osteochondrosis of the metatarsal head, rheumatoid arthritis can often cause the destruction of 2-5 metatarsophalangeal joint, leading to pain, limited joint movement and toe deformities, severely affecting the forefoot function. The purpose of this study is to report the results of middle-long term follow-up after performing Swanson double-stem silicon implant arthroplasty in patients with diseases of 2-5 metatarsophalangeal joint. METHODS: From January 2010 to October 2015, 21 patients with 2-5 metatarsophalangeal joint replacement were performed with Swanson double-stem silicone prosthesis. In the study, 16 cases were successfully followed up, 2 men and 14 women with an average age (66.7±5.5) years. There were 9 cases diagnosed with rheumatoid arthritis, 5 cases with severe osteoarthritis and 2 cases with osteochondrosis of the metatarsal head. The American Association of foot and ankle surgery Maryland foot scoring system and visual analogue score (VAS) were used to evaluate the walking function, metatarsophalangeal joint mobility and pain degree before and after surgery. RESULTS: The follow-up time ranged from 17 months to 5 years, with an average of 3.2 years. According to Maryland foot scoring system of the American Association of foot and ankle surgery, the preoperative score was (60.69±6.12) points and postoperative score was (88.13±5.84) points. Range of motion of metatarsophalangeal joint: preoperative: back extension 5.4°±3.1°, plantar flexion 4.4°±2.7°; postoperative: back extension 15.7°±4.5°, plantar flexion 12.2°±4.3°, the motion of 2-5 metatarsophalangeal joint after operation was significantly improved compared with that before operation (P < 0.01). The preoperative VAS was (6.8±0.9) points and the last follow-up was (2.3±0.8) points, the pain symptom of metatarsophalangeal joint was improved obviously after operation. The postoperative score was significantly higher than the preoperative score according to Maryland foot scoring system (P < 0.01), the excellent rate was 81.3%. CONCLUSIONS: With the advantages of alleviating pain, preserving the length and alignment of metatarsophalangeal joint, improving the function of walking, and correcting the deformity, Swanson double-stem silicon implant arthroplasty is a reproducible and safe option for the reconstruction of the 2-5 metatarsophalangeal joint. However, there is still some probability of adverse reactions and still room for improvement.

MiR-201-5p alleviates lipopolysaccharide-induced renal cell dysfunction by targeting NOTCH3.

OBJECTIVE: Lipopolysaccharide (LPS)-induced inflammation and dysfunction in the kidney may be the major risk factors for subsequent acute kidney injury (AKI). Previous studies have reported that up-regulation of notch receptor 3 (NOTCH3) expression is accompanied with renal epithelium and podocyte damage. Herein, we aimed to investigate whether NOTCH3 was involved in lipopolysaccharide (LPS)-induced AKI and renal cell dysfunction. MATERIALS AND METHODS: Septic mice were established using LPS (20 mg/kg) intraperitoneally. mRNA and protein expression in the kidney and renal cell was performed by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and Western blotting, respectively. Cell counting kit-8 (CCK8) and flow cytometry were used to measure cell viability and apoptosis, respectively. Bioinformatics algorithm and Luciferase reporter gene assay were performed to validate whether NOTCH3 was a direct target of miR-201-5p. RESULTS: Up-regulation of NOTCH3 and down-regulation of miR-201-5p were observed in the kidney of LPS-induced septic mice. LPS-stimulated TCMK-1 and MPC5 cells led to an increase in NOTCH3 and a decrease in miR-201-5p expression levels. Bioinformatics algorithm and experimental measurements validated that NOTCH3 was a direct target of miR-201-5p. Overexpression of miR-201-5p protected against LPS-induced renal cell growth inhibition, apoptosis and inflammatory response via the suppression of toll-like receptor 4 (TLR4)/NOTCH3 signaling pathway. CONCLUSIONS: The novel role of miR-201-5p via the inhibition of LPS-activated TLR4/NOTCH3 might provide a potential therapeutic strategy for the treatment of LPS-induced AKI.

Nucleus accumbens-associated protein-1 promotes glycolysis and survival of hypoxic tumor cells via the HDAC4-HIF-1α axis.

Nucleus accumbens-associated protein-1 (NAC1), a nuclear factor of the BTB/POZ gene family, has emerging roles in cancer. In this study, we identified the NAC1-HDAC4-HIF-1α axis as an important pathway in regulating glycolysis and hypoxic adaptation in tumor cells. We show that nuclear NAC1 binds to histone deacetylase type 4 (HDAC4), hindering phosphorylation of HDAC4 at Ser246 and preventing its nuclear export that leads to cytoplasmic degradation of the deacetylase. Accumulation of HDAC4 in the nuclei results in an attenuation of HIF-1α acetylation, enhancing the stabilization and transcriptional activity of HIF-1α and strengthening adaptive response of cells to hypoxia. We also show the role of NAC1 in promoting glycolysis in a mouse xenograft model, and demonstrate that knockdown of NAC1 expression can reinforce the antitumor efficacy of bevacizumab, an inhibitor of angiogenesis. Clinical implication of the NAC1-HDAC4-HIF-1α pathway is suggested by the results showing that expression levels of these proteins are significantly correlative in human tumor specimens and associated with the disease progression. This study not only reveals an important function of NAC1 in regulating glycolysis, but also identifies the NAC1-HDAC4-HIF-1α axis as a novel molecular pathway that promotes survival of hypoxic tumor cells.

Interaction of Sirt3 with OGG1 contributes to repair of mitochondrial DNA and protects from apoptotic cell death under oxidative stress.

Sirtuin 3 (Sirt3), a major mitochondrial NAD(+)-dependent deacetylase, targets various mitochondrial proteins for lysine deacetylation and regulates important cellular functions such as energy metabolism, aging, and stress response. In this study, we identified the human 8-oxoguanine-DNA glycosylase 1 (OGG1), a DNA repair enzyme that excises 7,8-dihydro-8-oxoguanine (8-oxoG) from damaged genome, as a new target protein for Sirt3. We found that Sirt3 physically associated with OGG1 and deacetylated this DNA glycosylase and that deacetylation by Sirt3 prevented the degradation of the OGG1 protein and controlled its incision activity. We further showed that regulation of the acetylation and turnover of OGG1 by Sirt3 played a critical role in repairing mitochondrial DNA (mtDNA) damage, protecting mitochondrial integrity, and preventing apoptotic cell death under oxidative stress. We observed that following ionizing radiation, human tumor cells with silencing of Sirt3 expression exhibited deteriorated oxidative damage of mtDNA, as measured by the accumulation of 8-oxoG and 4977 common deletion, and showed more severe mitochondrial dysfunction and underwent greater apoptosis in comparison with the cells without silencing of Sirt3 expression. The results reported here not only reveal a new function and mechanism for Sirt3 in defending the mitochondrial genome against oxidative damage and protecting from the genotoxic stress-induced apoptotic cell death but also provide evidence supporting a new mtDNA repair pathway.

Expression of Mina53 and its significance in gastric carcinoma.

AIM: To study the expression of Mina53 and its relationships with clinicopathological characteristics, antioncogene inactivation and tumor proliferation in human gastric carcinoma, and to explore the role of Mina53 in carcinogenesis and tumor progression. METHODS: Expression of Mina53 and proliferating cell nuclear antigen (PCNA) was determined in gastric carcinoma (n=79), gastric dysplasia (n=21) and normal gastric tissues (n=20), while p53 was measured in gastric carcinoma tissues by immunohistochemistry. RESULTS: Mina53 was negatively expressed in all normal mucosa tissues. Dysplasia specimens showed weakly positive staining for Mina53 in 3 of 21 cases. Elevated expression of Mina53 was observed in 72 (91.1%) of the gastric carcinomas. No significant associations were found between Mina53 and clinicopathological characteristics such as sex, age, histological differentiation, distant metastasis and lymph node metastasis (p>0.05). There was a significant association with depth of invasion (X2=5.385, p<0.05) and TMN stage (X2=6.255, p<0.05). In gastric carcinoma, positive staining for p53 was detected in 53 of 79 cases (67.1%), showing a significant association with Mina53 (X2=5.161, p<0.05). The mean (+/- SD) PCNA labeling index for gastric carcinoma was 39.47+/-16.92%. Mina53 expression was positively associated with PCNA level (r=0.756, p<0.01). CONCLUSION: Mina53 was overexpressed in gastric carcinoma and associated with tumor proliferation and antioncogene inactivation. Mina53 could therefore play an important role in the carcinogenesis and progression of gastric carcinoma.

[Determination of triptolide in human plasma by gas chromatography-electron capture detection].

A method for the determination of tiptolide in human plasma by gas chromatography-electron capture detection is described. An SE-54 capillary column (30 m x 0.25 mm i.d.) was used. Nitrogen was used as the carrier gas. After NaOH solution being added, the plasma was extracted with ether-chloroform (3:1, V/V) and then reacted with trifluoroacetic anhydride. A good linearity was obtained from 1.0 microgram/L to 50.0 micrograms/L of tiptolide in human plasma, r = 0.9990. The detection limit of it in plasma was 0.5 microgram/L. The average recovery was 96.3%. The method is sensitive and precise.

[Determination of bromhexine in plasma by gas chromatography-electron capture detection and pharmacokinetic studies].

This paper reports a gas chromatography-electron capture detection(GC-ECD) method for the study of pharmacokinetics of bromhexine in healthy human body. A2 m x 3 mm i.d. silanized glass column packed with 5% SE-30 was used. The carrier gas was nitrogen. The internal standard was 5-chloro-2-amino-diphenyl ketone. After NaH2PO4-Na2HPO4 buffer (pH 6.0) being added, the plasma was extracted with n-hexane-dichloromethane (9:1, V/V). A good linearity was obtained from 1.0 microgram/L to 50.0 micrograms/L of bromhexine in human plasma, r = 0.9994. The detection limit of bromhexine in plasma was 0.5 microgram/L. The average recovery was 97.5%. The pharmacokinetics of bromhexine was determined by this method after a single oral dose of 8 mg bromhexine capsule given to each of 8 volunteers. The results showed that the plasma concentration-time courses conformed to one compartment model. The established GC-ECD method is a good method for the determination of bromhexine in human plasma. The method is rapid, simple, precise and sensitive.

Acetylcholine-induced and nitric oxide-mediated vasodilation in burns.

Microvascular endothelial cells actively participate in local regulation of blood flow and blood-tissue exchange by producing various vasoactive substances including nitric oxide (NO). This study examined microcirculatory changes in the early stage of thermal injury and the NO-related mechanisms. Resistance arterioles of rat cremaster muscle were observed using intravital microscopy. Arteriolar diameter and flow velocity were measured and flow rate was calculated after administration of various vasoactive agonists in burns. In fluid-resuscitated rats with stable systemic blood pressure, microvascular caliber and blood flow were not significantly altered in the first hour following a 25% total body surface area full-thickness scald burn. Topical application of acetylcholine (ACh), an endothelium-dependent vasodilator, increased arteriolar diameter and flow rate in a dose-dependent fashion. The dose-responsive effects of ACh were significantly greater in burned rats than in sham-burned rats, and the augmentation was blocked by inhibition of NO production with NG-monomethyl-l-arginine (L-NMMA). Topical application of adenosine, an endothelium-independent vasodilator, and sodium nitroprusside, an exogenous NO donor, markedly increased arteriolar diameter and flow rate. The effects were not significantly different in burned and sham-burned animals, and the adenosine-induced vasodilation was not blocked by L-NMMA. These data suggest that endothelium-dependent and NO-mediated arteriolar dilation is enhanced in the early stage of thermal injury. This effect may play an important role in the pathophysiological events of microcirculation and blood-tissue exchange in burns.