Association of vitamin D receptor gene polymorphisms with systemic lupus erythematosus: a meta-analysis

OBJECTIVES

Vitamin D receptor gene polymorphisms has been shown to be associated with systemic lupus erythematosus (SLE). Several studies have been published which have investigated the association between VDR gene polymorphisms with SLE risk, but the results have been inconclusive. The study was designed to investigate whether the vitamin D receptor gene polymorphisms are associated with the risk of SLE.

METHODS

A meta-analysis was conducted on associations between the vitamin D receptor gene polymorphisms and SLE using (1) allele contrast and (2) the recessive, (3) the dominant, and (4) the additive models.

RESULTS

A total of 11 case-control studies of 1683 patients and 1883 unrelated healthy individuals were included. The results of meta-analysis indicated that the BsmI and FokI polymorphisms are associated with increased risk of SLE. The overall ORs are 2.14 [95%CI (1.20-3.82), p=0.01] ( BB + Bb vs. bb) and 1.75 [95%CI(1.03-2.97), P=0.04]( FF + Ff vs. ff), respectively, while the ApaI and TaqI polymorphism were not associated. In subgroup analysis by ethnicity, the increased risk of SLE remained in the Asian subgroup for the BsmI and FokI polymorphism, whereas no significant association was found in other populations for other polymorphisms.

CONCLUSIONS

The current study suggested that the BsmI and FokI polymorphism are associated with increased risk of SLE, especially in the Asian population, but further studies are needed to confirm our results.

Comparison of proximal turndown of central slip combined with suture of lateral bands versus free tendon grafting for central slip reconstruction after an open finger injury

We randomized patients with open finger injury and central slip insertion defects into a proximal turn-down group (final n = 28) and a palmaris longus tendon graft group (final n = 20). In the proximal turn-down group, the dorsal central slip of the extensor tendon in the proximal phalanx was split, leaving it attached distally. We turned the strip from proximal to distal and fixed it using the distal joint capsule of the proximal interphalangeal joint as the distal insertion of reconstruction, and the extended central slips were then fixed to the middle phalanx. The dorsal traumatic central slip was stitched with lateral bands using 2-0 suture to form a new conjoint tendon. The injured central slip in the comparison group was sutured using autogenous palmaris longus tendon and fixed in drilled holes in the middle phalanx. Outcomes assessment was performed according to Dargan's criteria during postoperative follow-up. Motion range in the proximal turndown group was significantly greater than in the graft group (p < 0.05). We observed no boutonniere deformity in both the proximal turndown and graft group.

HMGB1-LPS complex promotes transformation of osteoarthritis synovial fibroblasts to a rheumatoid arthritis synovial fibroblast-like phenotype

It is generally believed that some inflammatory antigens can recognize Toll-like receptors on synovial fibroblasts (SFs) and then activate downstream signals, leading to the formation of RASFs and inducing rheumatoid arthritis (RA). The objective of the current work was to study on the hypothesis that outer PAMP (LPS) binds to the inner DAMP (HMGB1) and becomes a complex that recognizes TLRs/RAGE on SFs, thus initiating a signaling cascade that leads to the secretion of inflammatory cytokines and chemokines, production of tissue-destructive enzymes, and formation of RASFs, finally resulting in RA. Osteoarthritis synovial fibroblasts (OASFs) were co-cultured with HMGB1–LPS complex in vitro for five generations to induce the transformation of human SFs to RA-like SFs (tOASFs). Then, changes of tOASFs in cell cycle and apoptosis–autophagy balance were investigated in vitro, and the pathogenicity of tOASFs was evaluated in a SCID mouse model in vivo. In vitro cell cycle analysis showed more tOASFs passing through the G1/S checkpoint and moving to S or G2 phase. Flow cytometry and confocal microscopy showed that apoptosis was reduced and autophagy was enhanced significantly in tOASFs as compared with those in OASFs. The expression of certain receptors and adhesion molecules in tOASFs was upregulated. In vivo experiments showed that tOASFs attached to, invaded, and degraded the co-implanted cartilage. In addition, histochemistry showed excessive proliferation of tOASFs and the expression of matrix metalloproteinases (MMPs). Based on the above findings, we conclude that HMGB1–LPS complex could promote the formation of RASFs.

Deep penetration of nanoparticulate drug delivery systems into tumors: challenges and solutions

In recent decades, nanoparticulate drug delivery systems have attracted extensive attention in cancer therapy for such appealing properties as small particle size, huge surface area, narrow size distribution and prolonged circulation time. Although several nanomedicines have successfully reached the clinical, evidences have proved that therapeutic efficacy isn't improved significantly, except for better toleration and less side effects. Given that the physiological abnormalities in tumors, multiple biobarriers need to be overcome before nanomedicines are delivered to the target site. Passive targeting nanoparticles ensure nanomedicines' extensive extravasation from tumor vessels via enhanced permeation and retention effect, but the diffusion distance is limited to 2-3 cell layer thicknesses. Active targeting nanoparticles tend to bind the peripheral cells of the tumor mass, hindering nanoparticles further penetration into the tumor core region. Therefore, how to improve the deep penetration of nanomedicines into tumors is a formidable task for achieving the desired anticancer therapeutic efficacy. This review demonstrates the penetration obstacles existing in tumor region for nanoparticles, summarizes the important properties of nanomedicines affecting tumor deep penetration and highlights the solutions to improve tumor deep penetration of nanoparticles.

Mesohepatectomy for centrally located liver tumours

BACKGROUND

Mesohepatectomy (MH) avoids unnecessary sacrifice of functional parenchyma compared with extended hepatectomy (EH). The aim of this study was to compare the results of MH with those of EH in the management of centrally located liver tumours (CLLTs).

METHODS

All patients with CLLTs treated by liver resection between 2005 and 2011 were enrolled in this retrospective study. The decision to use MH or EH was made on an individual basis. Outcomes of the procedures were compared and a classification system for MH was devised consisting of four types, with type IV representing the most complex procedure.

RESULTS

MH was performed in 292 patients and EH in 138. MH was associated with a longer duration of operation (P < 0.001), higher intraoperative transfusion rate (P < 0.001) and lower complication rates (P = 0.001) compared with EH. There were no significant differences in hepatic inflow occlusion rate (P = 0.075), blood loss (P = 0.241) and length of hospital stay (P = 0.804) between the two groups. Type IV lesions had the longest duration of operation, greatest blood loss, and highest intraoperative transfusion and morbidity rates (all P < 0.050).

CONCLUSION

MH is a feasible and safe alternative to EH in selected patients with CLLTs. The proposed classification system may be useful in guiding the surgical treatment of CLLTs.

Long-range ordered graphite oxide liquid crystals

Liquid crystallinity of graphite oxide prepared without the aid of sonication was observed, which exhibited a spontaneous highly-ordered alignment.

Morphologic control of Sb-rich Sb2Se3 to adjust its catalytic hydrogenation properties for p-nitrophenol

Sb-rich Sb₂Se₃ with hollow sphere morphology is an efficient catalyst for the hydrogenation of p-nitrophenol.

Glucomannan-mediated facile synthesis of gold nanoparticles for catalytic reduction of 4-nitrophenol

A facile one-pot approach for synthesis of gold nanoparticles with narrow size distribution and good stability was presented by reducing chloroauric acid with a polysaccharide, konjac glucomannan (KGM) in alkaline solution, which is green and economically viable. Here, KGM served both as reducing agent and stabilizer. The effects of KGM on the formation and stabilization of as-synthesized gold nanoparticles were studied systematically by a combination of UV-visible (UV-vis) absorption spectroscopy, transmission electron microscopy, X-ray diffraction, dynamic light scattering, and Fourier transform infrared spectroscopy. Furthermore, the gold nanoparticles exhibited a notable catalytic activity toward the reduction of 4-nitrophenol to 4-aminophenol.

Kinetically controlled self-assembly of redox-active ferrocene-diphenylalanine: from nanospheres to nanofibers

Putting metals into organic compounds such as peptides can lead to many new desirable properties. Here we designed a novel bioorganometallic molecule, ferrocene-diphenylalanine (Fc-FF), and investigated its self-assembly behavior. We directly observed a morphological transition from metastable nanospheres to nanofibers, which led to the formation of a self-supporting hydrogel. The strong hydrophobic interaction of the Fc moiety was suggested to have a key role in this kinetically controlled self-assembly process. Moreover, the redox center of the ferrocene group further allowed us to reversibly control the self-assembly behavior of Fc-FF by altering its redox state.

Preventing childhood falls within the home: overview of systematic reviews and a systematic review of primary studies

In most countries falls are the most common medically attended childhood injury and the majority of injuries in pre-school children occur at home. Numerous systematic reviews have reviewed evidence of the effectiveness of falls prevention interventions, but this evidence has not been synthesised into an overview, making it difficult for policy makers and practitioners to easily access the evidence. To synthesise all available evidence, we conducted an overview of reviews of home safety interventions targeting childhood falls, extracted data from primary studies included in the reviews and supplemented this with a systematic review of primary studies published subsequent to the reviews. Bibliographic databases, websites, conference proceedings, journals and bibliographies of included studies were searched for systematic reviews of studies with experimental or controlled observational designs. Thirteen reviews were identified containing 24 primary studies. Searches for additional primary studies identified five further studies not included in reviews. Evidence of the effect of interventions on falls or fall injuries was sparse, with only one of three primary studies reporting this outcome finding a reduction in falls. Interventions were effective in promoting the use of safety gates and furniture corner covers. There was some evidence of a reduction in baby walker use. The effect on the use of window safety devices, non-slip bath mats/decals and the reduction of tripping hazards was mixed. There was limited evidence that interventions were effective in improving lighting in corridors, altering furniture layout and restricting access to roofs. Most interventions to prevent childhood falls at home have not been evaluated in terms of their effect on reducing falls. Policy makers and practitioners should promote use of safety gates and furniture covers and restriction of baby walker use. Further research evaluating the effect of interventions to reduce falls and falls-related injuries is urgently required.

Association of NPP1 polymorphism with postoperative progression of ossification of the posterior longitudinal ligament in Chinese patients

Ossification of the posterior longitudinal ligament (OPLL) is a condition of the spine that can cause paralysis by compressing the spinal cord. The aim of this study was to evaluate the possible role of nucleotide pyrophosphatase phosphodiesterase 1 gene (NPP1) polymorphism in the etiology and pathology of the OPLL in Chinese patients. DNA from patients with OPLL (N = 95) and without OPLL (N = 90) were genotyped for 4 NPP1 single-nucleotide polymorphisms (SNPs): A533C, C973T, IVS15-14T→C, and IVS20-11delT. An association study evaluated the relationship between specific SNP genotypes and susceptibility. We also evaluated whether genotypes of these SNPs were associated with disease severity and the probability of disease progression after surgery. The C973T and IVS15-14T SNPs were associated with the existence of the disease. The TT genotypes of C973T and IVS15→14T as well wild-type IVS20 (lack of deletion) were associated with more severe disease. Patients with the T deletion of IVS20 or the AA genotype of A533C had an approximately 3 times greater chance of not having than having disease progression after surgery. We concluded that the 4 SNPs analyzed appeared to have different effects on the etiology and pathology of OPLL. To our knowledge, this study is the first to investigate the relationship between these SNPs and disease progression after surgery. Our findings suggest that the presence of specific genotypes of the IVS20-11delT and A533C SNPs may predict disease outcome after surgical intervention.

Metformin reverses multidrug resistance and epithelial-mesenchymal transition (EMT) via activating AMP-activated protein kinase (AMPK) in human breast cancer cells

Breast cancer is the most frequently diagnosed tumor type and the primary leading cause of cancer deaths in women worldwide and multidrug resistance is the major obstacle for breast cancer treatment improvement. Emerging evidence suggests that metformin, the most widely used antidiabetic drug, resensitizes and cooperates with some anticancer drugs to exert anticancer effect. However, there are no data regarding the reversal effect of metformin on chemoresistance in breast cancer. In the present study, we investigated the resistance reversal effect of metformin on acquired multidrug-resistant breast cancer cells MCF-7/5-Fu derived from MCF-7 breast cancer cells and innate multidrug-resistant MDA-MB-231 breast cancer cells, and we found that metformin resensitized MCF7/5-FU and MDA-MB-231 to 5-fluorouracil (5-FU), adriamycin, and paclitaxel. We also observed that metformin reversed epithelial-mesenchymal transition (EMT) phenotype and decreased the invasive capacity of MCF7/5-FU and MDA-MB-231 cells. However, there were no significant changes upon metformin-treated MCF7 cells. Moreover, we found metformin treatment activated AMPK signal pathway in MCF7/5-FU and MDA-MB-231 cells and compound C, the AMPK inhibitor, could partly abolish the resensitization and EMT reversal effect of metformin. To the best of our knowledge, we are the first to report that metformin can resensitize multidrug-resistant breast cancer cells due to activating AMPK signal pathway. Our study will help elucidate the mechanism of chemoresistance and establish new strategies of chemotherapy for human breast cancer.

Determination of quercetin, plumbagin and total flavonoids in Drosera peltata Smith var. glabrata Y.Z.Ruan

BACKGROUND

Drosera peltata Smith var. glabrata Y.Z.Ruan, a kind of wild carnivorous plants in the family Droseraceae, has been used for the treatment of rheumatism and bruises in Chinese folk. None of compounds in this herb has been quantified in the previous studies.

OBJECTIVE

To develop a validated and reliable HPLC method for the simultaneous determination of two bioactive constituents - quercetin and plumbagin, and establish a simple UV spectrophotometry method for the analysis of total flavonoids content.

MATERIALS AND METHODS

Chromatographic separation was performed by using a HPLC system consisting of an Agilent Eclipse XDB C18 column and a gradient elution system of acetonitrile and water (containing 0.1% phosphoric acid, V/V) within 20 minutes. Comparing with quercetin complex with Al(NO3)3, the total flavonoids were determined by UV spectrophotometry at 269 nm.

RESULTS

Both methods were validated for linearity (r(2)≥0.9994 for quercetin and plumbagin in the HPLC method, r(2) = 0.9994 for quercetin in the UV spectrophotometry method), precision (The within-day and between-day variability was less than 0.738% and 1.64% for quercetin and plumbagin in the HPLC method, and was less than 1.67% for quercetin in the UV spectrophotometry method.) and recovery (The recoveries of the HPLC method were 96.7-100.4% and 97.4-100.4% for quercetin and plumbagin, respectively, and the recovery of the UV spectrophotometry method was 96.7-99.6% for quercetin.).

CONCLUSION

The proposed methods are simple and accurate, and could be practiced to rapidly determine quercetin, plumbagin and total flavonoids in the herbal drug, which provide effective approaches for quality control.

A Bmi1-miRNAs cross-talk modulates chemotherapy response to 5-fluorouracil in breast cancer cells

The polycomb group transcriptional modifier Bmi1 is often upregulated in numerous cancers and is intensely involved in normal and cancer stem cells, and importantly is as a prognostic indicator for some cancers, but its role in breast cancer remains unclear. Here, we found Bmi1 overexpression in 5-Fu (5-fluorouracil)-resistant MCF-7 cells (MCF-7/5-Fu) derived from MCF-7 breast cancer cells, MDA-MB-231 and MDA-MB-453 breast cancer cells compared to MCF-7 cells, was related with 5-Fu resistance and enrichment of CD44⁺/CD24^- stem cell subpopulation. Bmi1 knockdown enhanced the sensitivity of breast cancer cells to 5-Fu and 5-Fu induced apoptosis via mitochondrial apoptotic pathway, and decreased the fraction of CD44⁺/CD24^- subpopulation. In addition, our analysis showed inverse expression pattern between Bmi1 and miR-200c and miR-203 in selected breast cancer cell lines, and miR-200c and miR-203 directly repressed Bmi1 expression in protein level confirmed by luciferase reporter assay. MiR-200c and miR-203 overexpression in breast cancer cells downregulated Bmi1 expression accompanied with reversion of resistance to 5-Fu mediated by Bmi1. Inversely, Bmi1 overexpression inhibited miR-200c expression in MCF-7 cells, but not miR-203, however ectopic wild-type p53 expression reversed Bmi1 mediated miR-200c downregulation, suggesting the repressive effect of Bmi1 on miR-200c maybe depend on p53. Thus, our study suggests a cross-talk between Bmi1 and miR-200c mediated by p53, and Bmi1 interference would improve chemotherapy efficiency in breast cancer via susceptive apoptosis induction and cancer stem cell enrichment inhibition.

Risk factors for postoperative wound complications of calcaneal fractures following plate fixation

BACKGROUND

A fairly high prevalence of wound complications after open reduction and internal plate fixation (ORIF) of closed calcaneal fractures via the extensile lateral approach has been reported. The goal of this study was to analyze and identify independent risk factors for wound complications among closed calcaneal fractures undergoing ORIF.

METHODS

The medical records of all closed calcaneal fracture patients who underwent ORIF from July 2005 to July 2012 were reviewed to identify those who developed a wound complication. Then we constructed a univariate and multivariate logistic regression to evaluate the independent associations of potential risk factors for surgical wound complication. Records showed 479 patients who underwent ORIF of a closed calcaneal fracture from July 2005 to July 2012. The patients were followed for 3 to 28 months, with an average follow-up period of 14.2 months. Eleven patients had bilateral fractures, for a total of 490 fractured calcanei.

RESULTS

The overall rate of postoperative wound complications following ORIF of closed calcaneus fractures was 17.8% (87 wound complications in 490 operations). With the regression model, smoking history (odds ratio, 5.79; 95% CI: 1.55 to 21.70; P = .009), diabetes mellitus (odds ratio, 6.23; 95% CI: 1.37 to 28.31; P = .018), Sanders type (odds ratio, 5.44; 95% CI: 2.02 to 14.64; P = .001), number of residents and/or fellows present during the case (odds ratio, 1.63; 95% CI: 1.06 to 2.52; P = .028), duration of surgery (odds ratio, 4.54; 95% CI: 1.46 to 14.12; P < .001), estimated blood loss (odds ratio, 1.02; 95% CI: 1.01 to 1.04%; P < .001), and 10 or more people present in the operating room during the entire case (odds ratio, 2.30; 95% CI: 1.79 to 2.94; P < .001) were risk factors for wound complication. Tourniquet use (odds ratio, 0.02; 95% CI: 0.00 to 0.08; P < .001), which was associated with a decreased risk for the development of a wound complication, was observed as a protective factor. Diabetes mellitus, Sanders type, and smoking were the strongest risk factors for postoperative wound complication after adjusting for all other variables.

CONCLUSIONS

Smoking, diabetes mellitus, Sanders type, number of residents and/or fellows present during the case, duration of surgery, estimated blood loss, and high number of persons present in the operating room during the entire case were related to an increased risk for postoperative wound complication of closed calcaneal fractures following ORIF. Tourniquet use was associated with a decreased risk for the development of a wound complication.

LEVEL OF EVIDENCE

Level III, retrospective comparative series.

Low concentration of metformin induces a p53-dependent senescence in hepatoma cells via activation of the AMPK pathway

The induction of senescence for cancer treatment has provoked considerable interest recently. Metformin, a first-line drug for diabetes mellitus type 2, appears to be associated with a lower risk and improved outcomes in hepatocellular carcinoma (HCC). The mechanism involved in function of metformin in HCC is poorly understood. We show that low doses of metformin induced hepatoma cell senescence characterized by accumulation of senescence-associated β-galactosidase activity (SA-β-gal) and the senescence marker Dec1, whereas the higher doses initiated apoptotic cell death. Metformin-induced senescence was accompanied by enhanced phosphorylation levels of AMP-activated protein kinase (AMPK) and its downstream target acetyl-CoA carboxylase (ACC). The expression of acetylated p53 at Lys382 (Ac-p53) and p21 was also increased, while phosphorylation of p53 at Ser15 (p-p53), p53, p16 and pRB was rarely altered after metformin treatment. Moreover, inhibition of AMPK decreased p-AMPK, p-ACC, Ac-p53 and p21 expression, diminished SA-β-gal staining and restored hepatoma cell proliferation. In addition, p53 siRNA transfection attenuated metformin-induced SA-β-gal staining. Intriguingly, co-expression of SIRT1 and p53 dramatically reduced the levels of Ac-p53, however, low doses of metformin treatment partially reversed the effect of SIRT1 on p53 acetylation and elevated SA-β-gal activity. These observations indicate that activation of the AMPK pathway promotes senescence in hepatoma cells exposed to low concentrations of metformin in a p53-dependent manner. Further, low doses of metformin may have the potential to be used as an adjuvant to HCC therapy.