Identification of potential biomarkers of gout through weighted gene correlation network analysis.

Background: Although hyperuricemia is not always associated with acute gouty arthritis, uric acid is a significant risk factor for gout. Therefore, we investigated the specific mechanism of uric acid activity. Methods: Using the gout-associated transcriptome dataset GSE160170, we conducted differential expression analysis to identify differentially expressed genes (DEGs). Moreover, we discovered highly linked gene modules using weighted gene coexpression network analysis (WGCNA) and evaluated their intersection. Subsequently, we screened for relevant biomarkers using the cytoHubba and Mcode algorithms in the STRING database, investigated their connection to immune cells and constructed a competitive endogenous RNA (ceRNA) network to identify upstream miRNAs and lncRNAs. We also collected PBMCs from acute gouty arthritis patients and healthy individuals and constructed a THP-1 cell gout inflammatory model, RT-qPCR and western blotting (WB) were used to detect the expression of C-X-C motif ligand 8 (CXCL8), C-X-C motif ligand 2 (CXCL2), and C-X-C motif ligand 1 (CXCL1). Finally, we predicted relevant drug targets through hub genes, hoping to find better treatments. Results: According to differential expression analysis, there were 76 upregulated and 28 downregulated mRNAs in GSE160170. Additionally, WGCNA showed that the turquoise module was most strongly correlated with primary gout; 86 hub genes were eventually obtained upon intersection. IL1ß, IL6, CXCL8, CXCL1, and CXCL2 are the principal hub genes of the protein-protein interaction (PPI) network. Using RT-qPCR and WB, we found that there were significant differences in the expression levels of CXCL8, CXCL1, and CXCL2 between the gouty group and the healthy group, and we also predicted 10 chemicals related to these proteins. Conclusion: In this study, we screened and validated essential genes using a variety of bioinformatics tools to generate novel ideas for the diagnosis and treatment of gout.

Porphyrin Functionalized Carbon Quantum Dots for Enhanced Electrochemiluminescence and Sensitive Detection of Cu2.

Porphyrin (TMPyP) functionalized carbon quantum dots (CQDs-TMPyP), a novel and efficient carbon nanocomposite material, were developed as a novel luminescent material, which could be very useful for the sensitive detection of copper ions in the Cu2+ quenching luminescence of functionalized carbon quantum dots. Therefore, we constructed a sensitive "signal off" ECL biosensor for the detection of Cu2+. This sensor can sensitively respond to copper ions in the range of 10 nM to 10 µM, and the detection limit is 2.78 nM. At the same time, it has good selectivity and stability and a benign response in complex systems. With excellent properties, this proposed ECL biosensor provides an efficient and ultrasensitive method for Cu2+ detection.

TSAb Modulates Microglia M1 Polarization via Activation of the TSHR-Mediated NF-κB Signaling Pathway.

INTRODUCTION: Thyrotropin receptor-stimulating antibody (TSAb) is a pathogenic antibody in the serum of patients with Graves' disease. The binding of TSAb to thyroid-stimulating hormone receptor (TSHR) in non-thyroid tissue may be associated with the occurrence and development of Graves' disease-related complications. However, only few studies have been conducted on the effects of TSAb on the brain, and the pathogenesis of acute hyperthyroidism myopathy (ATM) is unclear. Therefore, this study aimed to explore the effect of TSAb on the polarization of BV-2 cells in the brain and its possible mechanism and provide a basic experimental basis for ATM. METHODS: BV-2 cells were treated with different concentrations of TSAb. The relative survival rate of BV-2 cells was determined using the CCK-8 assay; the migration ability of BV-2 cells was detected using the Transwell migration assay; and the expression levels of M1/M2 polarization markers (CD86, inducible nitric oxide synthase [iNOS], CD206, and arginase 1 [Arg-1]), TSHR, tumor necrosis factor-alpha (TNF-α), and nuclear factor-kappa B (NF-κB) protein in BV-2 cells were measured using WB. RESULTS: Compared with the negative control group, the proliferative activity of BV-2 cells was significantly increased in the 20, 50, and 100 ng/mL TSAb groups, and the migration ability of BV-2 cells was significantly enhanced in the 50 and 100 ng/mL TSAb groups. The expression levels of M1 polarization markers (CD86 and iNOS), TSHR, TNF-α, and NF-κB protein in BV-2 cells treated with 50 and 100 ng/mL TSAb for 24 h were significantly upregulated, whereas those of M2 polarization markers (CD206 and Arg-1) significantly decreased. CONCLUSIONS: TSAb can induce abnormal activation of microglia, polarize to the M1 phenotype, and promote the inflammatory cascade reaction, in which TSHR plays a key role in NF-κB activation and proinflammatory cytokine release.

New Horizons for MXenes in Biosensing Applications.

Over the last few decades, biosensors have made significant advances in detecting non-invasive biomarkers of disease-related body fluid substances with high sensitivity, high accuracy, low cost and ease in operation. Among various two-dimensional (2D) materials, MXenes have attracted widespread interest due to their unique surface properties, as well as mechanical, optical, electrical and biocompatible properties, and have been applied in various fields, particularly in the preparation of biosensors, which play a critical role. Here, we systematically introduce the application of MXenes in electrochemical, optical and other bioanalytical methods in recent years. Finally, we summarise and discuss problems in the field of biosensing and possible future directions of MXenes. We hope to provide an outlook on MXenes applications in biosensing and to stimulate broader interests and research in MXenes across different disciplines.

Curcumin induces apoptosis and inhibits the growth of adrenocortical carcinoma: Identification of potential candidate genes and pathways by transcriptome analysis.

Adrenocortical carcinoma (ACC) is an endocrine tumour with high malignancy, high invasiveness and poor prognosis. Curcumin, a major component in turmeric, has been reported to have good efficacy and biological safety in treating cancer. However, the role and mechanism of curcumin in ACC have not yet been fully investigated and were thus the focus of this study. In vitro, ACC SW-13 and NCI-H295R cells were treated with curcumin and their viability, migration and invasion were assessed by CCK-8 and Transwell assays. Apoptosis was detected via flow cytometry and western blotting. High-throughput sequencing and comprehensive bioinformatics analyses were performed to elucidate the molecular processes underlying curcumin activity. In vivo, SW-13 cells were injected into nude mice, and the tumour volumes and weights were observed after 2 weeks of curcumin treatment. Organelle changes were observed by electron microscopy, and potential candidate genes and pathways were analysed by RT-qPCR and western blotting. The role of the CHOP target gene in curcumin-induced ACC cell apoptosis was verified via lentiviral transfection experiments. Curcumin inhibited the viability, migration and invasion, and induced the apoptosis of ACC cells. Transcriptome sequencing analysis showed that curcumin treatment markedly changed the gene expression levels. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses showed that the MAPK and endoplasmic reticulum (ER) stress pathways were the predominant pathways associated with curcumin-induced apoptosis of ACC cells. Subsequent in vivo and in vitro results demonstrated that the JNK, p38 MAPK and ER stress pathways were activated in curcumin-treated ACC cells, and that C/EBP homologous protein induction was responsible for curcumin-induced apoptosis of ACC cells. In summary, curcumin induced ACC cell apoptosis and inhibited tumour growth by activating the JNK, p38 MAPK and ER stress pathways. Thus, curcumin may be a potential therapeutic drug for ACC.

Tauroursodeoxycholic acid mediates endoplasmic reticulum stress and autophagy in adrenocortical carcinoma cells.

Adrenocortical carcinoma (ACC) is an invasive tumor that occurs in the endocrine system. Increasing evidence has shown that endoplasmic reticulum (ER) stress and autophagy play an important role in tumor formation. Tauroursodeoxycholic acid (TUDCA) is an ER chemical chaperone that can alleviate ER stress. In the present study, TUDCA promoted the proliferation, migration and invasion of ACC SW-13 and NCI-H295R cells. Reverse transcription-quantitative PCR and western blot analysis showed that the expression of glucose-regulated protein 78, a promoter of ER stress, was decreased. The expression levels of protein kinase R (PKR)-like ER kinase and activating transcription factor 6 were correspondingly decreased, and the downstream proteins, C/EBP homologous protein and JNK, were also decreased. The expression levels of the autophagy factor microtubule-associated protein light chain 3-II/I and the anti-apoptotic factor Bcl-2 increased following TUDCA treatment, while the expression of the pro-apoptotic factor Bax decreased. TUDCA alleviated ER stress in ACC SW-13 and NCI-H295R cells and induced autophagy, thereby inhibiting ACC cell apoptosis. ER stress- and autophagy-related signaling pathways are involved in the occurrence of ACC, which may provide potential therapeutic targets for ACC treatment.

Differences in clinical characteristics and prognosis of Penicilliosis among HIV-negative patients with or without underlying disease in Southern China: a retrospective study.

BACKGROUND: The incidence of Penicillium marneffei infection has recently increased. This fungus can cause fatal systemic mycosis in both immunocompetent and immunocompromised patients without HIV infection. METHODS: We retrospectively analysed Penicilliosis patients between January 1, 2003 and August 1, 2014 at the First Affiliated Hospital of Guangxi Medical University. HIV-negative patients with Penicilliosis were divided into two groups: patients with underlying disease (Group D) and patients without underlying disease (Group ND). HIV-positive patients were excluded. The relationships between overall survival and the study variables were assessed using univariate and multivariate analyses. RESULTS: During 11 years, Penicillium marneffei infection was diagnosed in 109 patients. Sixty-six (60.55 %) patients were HIV-positive and excluded from these cases. Forty-three patients were HIV-negative were enrolled. Among these patients, 18 (41.86 %) patients were in Group D, and 25 (58.14 %) were in Group ND. The most common underlying disease was diabetes. There were no statistically significant differences between the two groups in clinical characteristics, except for immune state and prognosis. Group ND had higher lymphocyte cell counts, CD4 cell counts, and CD4 T-cell percentages than Group D (P < 0.05). Patients in Group D had higher recurrence and mortality rates than Group ND (P < 0.05). In the univariate analysis, only underlying disease, CD4 cell percentage, and T lymphocyte cell percentage were significantly associated with overall survival. CONCLUSIONS: Penicillium marneffei can infect HIV-negative patients and can cause fatal systemic mycosis. There were no clear differences in clinical manifestations among HIV-negative patients with and without underlying disease. However, Penicillium marneffei in HIV-negative patients in with underlying diseases may cause immune function decline and a deficiency in T-cell-mediated immunity. Underlying disease, CD4 cell percentage, and T lymphocyte cell percentage may be potential risk factors affecting prognosis. Timely, effective, and longer courses of antifungal treatments are important in improving prognoses.

The correlation of plasma omentin-1 with insulin resistance in non-obese polycystic ovary syndrome.

OBJECTIVES: Aberrant circulating adipokines are considered to be related to the pathological mechanism of polycystic ovary syndrome (PCOS). This study aims to evaluate the relationship between plasma omentin-1 levels, metabolic and hormonal parameters in the setting of non-obese Chinese women with PCOS. MATERIAL AND METHODS: This was a case-controlled, cross-sectional study of 153 non-obese (BMI<25kg/m(2)) PCOS and 114 age-matched healthy non-obese control individuals. Levels of plasma omentin-1, fasting blood glucose, insulin and sexual hormones and ovary volume were analyzed in all subjects. RESULTS: Plasma omentin-1 levels of non-obese PCOS individuals were significantly lower than in healthy non-obese controls. Body Mass Index (BMI), homeostasis model of assessment for insulin resistance index (HOMA-IR), levels of testosterone, luteinizing hormone (LH) and follicle-stimulating hormone (FSH), LH/FSH ratio and ovary volume (OV) were significantly higher in subjects with PCOS than controls. In the HOMA-IR stratified subgroups, PCOS individuals with insulin resistance had lower omentin-1 than those without insulin resistance after BMI adjustment. Omentin-1 was negatively correlated with BMI, HOMA-IR and fasting insulin. Multiple linear regressions revealed that BMI contributed to omentin-1 levels. Ovary volume was negatively correlated to HOMA-IR but had no correlation with omentin-1. CONCLUSIONS: Plasma omentin-1 concentrations were decreased in the non-obese PCOS group. Insulin resistance could further decrease plasma omentin-1 in non-obese individuals with PCOS independent of BMI status.

A Retrospective Analysis of 7 Human Immunodeficiency Virus-Negative Infants Infected by Penicillium marneffei.

Infection with Penicillium marneffei has rarely been reported in human immunodeficiency virus (HIV)-negative infants. We aimed to determine the epidemiological, clinical, pathological, and immunological characteristics of 7 HIV-negative infants infected by P. marneffei, and to provide insights into its diagnosis and treatment.We retrospectively reviewed the cases of 7 HIV-negative infants infected by P. marneffei who presented to the First Affiliated Hospital of Guangxi Medical University between January 1, 2003 and December 1, 2014. The infants' median age was 23.43 months (SD = 8.34), and all lived in Guangxi Province in China, where P. marneffei is endemic. The median time from disease onset to diagnosis was 2.29 months (SD = 2.12). Of the cases studied, 5 (71.43%) had medical histories that included frequent pneumonia or bronchopneumonia, thrush, congenital megacolon, glucose-6-phosphate dehydrogenase deficiency, and hemophagocytic syndrome. The most common symptoms were fever, cough, and anemia, followed by lymphadenopathy, hepatosplenomegaly, and being underweight. Four patients had slightly elevated white blood cell counts. The lymphocyte and CD4 T-cell counts were normal. The CD8 T-cell counts, serum immunoglobulin (Ig) G titer, and serum IgA titer were low in 5 patients, and the serum IgM titers were high in 3 infants. Caseous necrosis was observed in 3 patients whose lymph nodes were affected. One case who received intravenous amphotericin B and 3 cases who received intravenous voriconazole improved, and these patients were cured after continual treatment with oral voriconazole for 6 or 12 months. The remaining patients died before they received antifungal treatment.P. marneffei causes severe disease and disseminated infections, and it has high mortality rates in HIV-negative infants in endemic areas. P. marneffei susceptibility may be associated with immunodeficiencies or immune disorders. In endemic areas, clinicians should aware of disseminated P. marneffei infections when infants present with serious or recurrent infections, even if they are HIV negative. P. marneffei is highly susceptible to amphotericin B and voriconazole. Timely diagnosis and treatment can improve patients' prognoses. Intravenous voriconazole could be recommended as the initial antifungal agent for HIV-negative infants infected by P. marneffei, because of its low nephrotoxicity, high sensitivity, and high efficacy levels.

Treatment of Disseminated Talaromyces marneffei with Tracheal Infection: Two Case Reports.

Talaromyces marneffei infection involving the trachea presents as diffuse irregular nodules that grow on the tracheal lumen and/or rarely present as concurrent severe eosinophilia. Herein, we report two patients without HIV infection whose main tracheal and/or principal bronchi were involved by T. marneffei infection, which manifested as diffuse proliferative nodules. In case 1, the infection primarily affected the main trachea, resulting in structural cartilage damage, tracheal stenosis, and tracheal absence. In case 2, there were diffuse proliferative nodules in the trachea and bronchi with marked eosinophilia. The final diagnosis was made based on a positive culture from bronchiolar lavage fluid, skin, and tracheal polyps. Case 1 was administered antifungal treatment combined with surgery, but relapse occurred during a 3-month follow-up period. Case 2 was treated by intravenous liposomal amphotericin B combined with atomized inhaled liposomal amphotericin B, and he later showed improvement; there was no relapse during the 12-month period of antifungal treatment. Importantly, atomized inhaled amphotericin B antifungal treatment for T. marneffei infection has never been previously reported.

A Meta-analysis Reveals S-1-based Chemotherapy Improves the Survival of Patients With Advanced Gastric Cancer.

The aim of this study was to compare the efficacy and safety of S-1-based therapy versus non-S-1-based therapy in advanced gastric cancer (AGC) patients.Eligible studies stratifying objective response rate (ORR), progression-free survival (PFS), overall survival (OS), and adverse events (AEs) in AGC patients were identified from Embase, Pubmed, Cochrane Library, and China National Knowledge Infrastructure databases. The STATA package (version 11.0) was used to pool the data from the eligible studies.Fifteen studies with 2973 AGC cases, of which 1497 (50.4%) received S-1-based therapy and 1476 (49.6%) received non-S-1-based therapy, were identified in the meta-analysis. AGC patients who had received S-1-based therapy had a higher median OS, median PFS, and ORR than those who had received 5-fluorouracil (FU)-based therapy (OS: hazard ratio [HR] 0.89, 95% confidence interval [CI] 0.80-0.98, P = 0.015; PFS: HR 0.88, 95% CI 0.80-0.98, P = 0.016; ORR: OR 1.25, 95% CI 1.08-1.45, P = 0.003, respectively). S-1-based therapy had similar efficacy to capecitabine-based therapy in terms of median OS (HR 1.14, 95% CI 0.91-1.41, P = 0.253), median PFS (HR 1.01, 95% CI 0.82-1.25, P = 0.927), and ORR (OR 0.84, 95% CI 0.63-1.12, P = 0.226). Subgroup analysis for grade 3 to 4 toxicity showed higher incidence of neutropenia (relative risk [RR] = 0.827, P = 0.006), nausea (RR = 0.808, P = 0.040), and lower diarrhea (RR = 1.716, P = 0.012) in 5-FU-based arm, and higher diarrhea (RR = 0.386, P = 0.007) in capecitabine-based arm.S-1-based chemotherapy is favorable to AGC patients with better clinical benefit than 5-FU-based chemotherapy and with equivalent antitumor compare with capecitabine-based therapy.

A novel approach for enriching cancer stem cells from the human SW-13 adrenocortical carcinoma cell line.

The present study was undertaken to develop a new method for enriching cancer stem cells (CSCs) from the human adrenal cortical carcinoma (ACC) cell line SW-13. Given that the existence of CSCs in ACC causes resistance to conventional chemotherapies, treatment with cyclophosphamide was used for in vivo selection of CSCs in a BALB/c nude mouse tumor xenograft model established using the ACC cell line SW-13. The characteristics of CSCs in three generations of tumor xenografts were assessed for single-cell colony formation, flat colony formation, and cell sphere formation in serum-free suspension culture. The formation rates of single-cell colonies, flat colonies, and cell spheres were significantly higher for tumor xenograft cells treated with cyclophosphamide than for untreated engrafted tumor cells. Flow cytometry to examine expression of the CSC markers C-X-C chemokine receptor type-4 (CXCR4; CD184) and ATP-binding cassette sub-family G member-2 (ABCG2; CDw338) revealed markedly higher levels of CXCR4 and ABCG2 in cyclophosphamide-treated xenograft tumor cells compared to untreated tumor cells. Together, these results indicate that cyclophosphamide treatment of tumor xenograft cells caused enrichment of CSCs with a strong capability for self-renewal and proliferation. In this method, the administration of cyclophosphamide selectively kills cancer cells without toxicity to CSCs and thereby provides a practical approach for achieving the enrichment of CSCs in ACC.

Pilon fractures: a new classification and therapeutic strategies.

BACKGROUND: Operative decision-making of Pilon fractures are of great challenges until now. The aim of this study was to investigate the guidance of the four-column theory in decision-making therapeutic strategies for Pilon fractures and its result. METHODS: One hundred and ten cases (107 patients) of Pilon fractures classified by the four-column theory and treated by ORIF, were reviewed. According to the four-column classification scheme, lateral column of 85 cases, posterior column of 66 cases, medial column of 77 cases, and anterior column of 61 cases are involved. Among all the 110 cases, single column of 14 cases, two columns of 46 cases, three columns of 17 cases, and all of four columns of 33 cases are involved. RESULTS: One hundred and eight cases have been followed up. The average follow up time is 14.7 months, varying between 7 and 52 months. The average healing time is 3.6 months, ranging from 2.5 to 8.0 months. Reduction of 86.1% reviewed Pilon cases are good or acceptable according to Burwell and Charley's Radiology Evaluation System. Ankle function of 87.1% cases are excellent or good according to the AOFAS evaluation system. CONCLUSION: As a simple and comprehensive classification, the four-column classification can contribute to reasonable operation decision-making and good prognosis of Pilon fracture.

[Effectiveness of a double-tsuge suture method in repairing Achilles tendon ruptures].

OBJECTIVE: To investigate the effectiveness of a double-tsuge suture method with absorbable polydioxanone-cord (PDS-II) in repair of Achilles tendon ruptures. METHODS: Between January 2005 and December 2008, 36 patients suffering from Achilles tendon ruptures were treated operatively. Of 36 patients, there were 29 males and 7 females with a mean age of 36 years (range, 21-50 years), including 22 cases of acute closed injuries, 6 cases of fresh open injuries (the time between injury and hospitalization was 1-10 days, mean 6 days), and 8 cases of old closed injuries (the time between injury and hospitalization was 43-63 days, mean 51 days). The injury reasons were sport injury (25 cases), incised injury (6 cases), falling injury (4 cases), and other (1 case). The results of "heel test" and the Thompson sign were positive in all patients. Operation was performed by using a double-tsuge suture method with a No. 0 PDS-II. After the ankle joint was fixed with short leg plaster cast at 30 degrees plantar flexion position for 6 weeks, the cast was removed and then functional exercises were done. RESULTS: Poor healing of incision occurred in 2 cases of old Achilles tendon ruptures and was cured after symptomatic treatment; healing of incision by first intention was achieved in the others. The patients were followed up 12 to 24 months (mean, 15 months). No rerupture, deep venous thromboembolism, or reflex sympathetic dystrophy occurred during follow-up. When compared with the range of motion of ankle joint of normal side, 7 cases had no change, 16 cases had a loss of 1-10 degrees, 12 cases had a loss of 10-20 degrees, and 1 case had a loss of 25 degrees. The average score was 90 (range, 74-96) according to Termann clinical evaluation criterion; the results were excellent in 24 cases, good in 11 cases, and fair in 1 case, and the excellent and good rate was 97.2%. CONCLUSION: The double-tsuge suture method is easy-to-operate, which has the smallest interference to the blood supply of Achilles tendon because of no crossing or transversal intratendon suture. PDS-II can provide highly strong stability, furthermore, it can be degenerated completely with tiny foreign body reaction, so there is no tendency to develope local adhesion. This technique achieves good results and is associated with a low morbidity of complications.

[New strategy for decision making of Pilon fracture].

OBJECTIVE: To study the guidance of four column theory in decision making of Pilon fractures and its result. METHODS: Ninety-one cases of Pilon fractures classified by four column method and treated by open reduction internal fixation (ORIF) were reviewed from March 2005 to June 2009. Four column classification:lateral column of 67 cases were involved, posterior column of 34 cases were involved, medial column of 34 cases were involved and anterior column of 34 cases were involved. Among all the 94 fractures, single column of 20 fractures were involved, 2 columns of 49 fractures were involved, 3 columns of 15 fractures were involved and all of 4 columns of 10 fractures were involved. RESULTS: Eighty-nine cases had been followed up. The average follow-up time was 16.2 months ranging between 6.0 and 39.0 months. The average healing time was 3.7 months ranging from 3.0 to 5.0 months. Reduction of 91% reviewed Pilon cases were good or acceptable according to Burwell and Charley's radiology evaluation system. Ankle function of 87.6% cases were excellent or good according to AOFAS evaluation system. CONCLUSION: As a simple and comprehensive classification, four column classification can contribute to reasonable operating decision making and good prognosis of Pilon fracture.

[Arthroscopic assisted diagnosis and treatment of knee extension limitation].

OBJECTIVE: To figure out the incidence and etiology of knee extension limitation and then to find out the proper methods of arthroscopic assisted diagnosis and treatment. METHODS: We reviewed 303 cases of arthroscopic assisted operation from January to October 2003, 95 cases of which suffered from knee extension limitation before operation, including 54 male and 41female and the mean age was 36.2 years old. The direct reasons of knee extension limitation were identified by routine arthroscopic examination and operations were carried out according to results of the examination. RESULTS: Incidence of knee extension limitation in this group of patients was 31.4%. Trauma, mainly meniscus and ligament injury accounted for 67.4%, which was the most common reason of knee extension limitation. Acute or chronic arthritis like degenerative arthritis, non-specific synovitis, synovial chondromatosis, rheumatoid arthritis, pigmented villonodular synovitis, gouty arthritis and acute pyogenic arthritis formed another common reason. The follow-up period ranged from 3 to 20 months, average 13.3 months. 82 cases gained full extension immediately after operation, 9 cases gained full extension after 3 weeks rehabilitation post-operation, 4 cases did not gain full extension 1 year after operation, recurrence was observed in 4 cases. CONCLUSIONS: Arthroscopy is the best method for diagnosis of knee extension limitation at present. Satisfactory results can be expected after early arthroscopic assisted treatment.

[Favorable effect of chitosan sustained-release FK506 incorporated conduits on axonal regeneration in rat sciatic nerve].

OBJECTIVE: To investigate the efficacy of 3 mm gap bridging repairing neurotmesis with chitosan sustained-release FK506 incorporated conduits. METHODS: Forty-five adult male SD rats were divided randomly into 3 groups. The rats were received a neurotomy to bilateral sciatic nerve and subsequently reconnected with regeneration chambers. The bridging conduits of group A, B and C were made of silicon tube, chitosan and chitosan sustained-release FK506 incorporated respectively. Conduits absorption and surrounding tissue cicatrization were observed at 6, 8 and 12 weeks after neurotomy. The nerve regeneration and functional recovery were evaluated by electrophysiology, histological changes, morphometric analysis, and weighing of gastrocnemius muscles. RESULTS: The silicon tubes of group A adhered severely with surrounding tissue. Bridging grafts of group B and C adhered relatively slightly and could be stripped easily from surrounding tissue. The regeneration chambers still existed fully at 6 weeks and began to be degraded at 8 weeks after neurotomy. The bridging grafts of group B and C were disintegrated at 12 weeks and the continuity of sciatic nerve was established without obvious adhesion with surrounding tissue. The statistical evaluation for nerve regeneration demonstrated that rats of group C showed the best results. Although rats of group B and A were found to be the second and the third respectively, there is no significant difference between them. CONCLUSION: Remaining 3 mm gap bridging repairing rat sciatic nerve with chitosan sustained-release FK506 incorporated conduits, which stabilize for more than 2 months before degradation in vivo, can significantly promote nerve regeneration and facilitate function recovery without adverse effects.

Differential expression of human telomerase catalytic subunit mRNA by in situ hybridization in pheochromocytomas.

In pheochromocytomas, it is very difficult to predict malignant potential by conventional histology or immunohistochemical and molecular markers. We investigated the expression of human telomerase catalytic component (hTERT) mRNA, hTERT protein, Ki-67 antigen, and p27kip1 in pheochromocytomas (27 benign, 7 suspected malignant, and 7 malignant), and evaluated the possibility of expressions of these proteins, and hTERT mRNA serve as diagnostic markers for predicting the biological behavior of these tumors. All tumors showed the classical histology and typical immunohistochemical pattern. By in situ hybridization, hTERT mRNA was expressed in 5/7 malignant tumors (defined as the presence of metastasis and/or extensive local invasion) as compared with 3/27 benign tumors. We examined the hTERT by immunohistochemistry to confirm the mRNA. hTERT mRNA expression was correlated with hTERT protein expression. All benign tumors exhibited no immunopositivity or <1% of cells stained for Ki-67 antigen. Six out of seven malignant tumors have shown either hTERT mRNA expression or Ki-67 immunoreactivity. While no statistical difference in p27kip1 expressions was observed among benign, malignant, and suspected malignant tumors, there was a statistical difference between the normal adrenal medulla samples and tumors (p < 0.001). Thus, hTERT mRNA detection by in situ hybridization, hTERT expression, and Ki-67 antigen expression are all useful tools for differentiating malignant from benign pheochromocytomas.

[Effect of FK506 on axonal regeneration of rat sciatic nerve in regeneration chamber: an experimental study].

OBJECTIVE: To evaluate the effect of FK506 on expediting nerve regeneration of rat Sciatic Nerve in regeneration chamber and to look for a proper way of its administration to treat peripheral nerve injuries. METHODS: Sixty adult male SD rats which were randamizely divided into 3 groups received a neurotomy to bilateral sciatic nerves, then we reconnected the broken nerves with silicon tube to make regeneration chambers. The regeneration chambers were filled with either normal saline (group A and group B) or 1 microg/ml FK506 (group C). The rats of group B also received daily injection of FK506 (1 mg/kg) at the back of the neck for 14 days. Local immunoreaction, weight of fresh gastrocnemius muscles, histological changes and electrophysiology were observed at designate time after neurotomy. RESULTS: At 6 weeks postoperation the extent of local lymphocytes infiltration in group B and C were less than that in group A, all results in group B were much better than that of group A. Results of group C were better than that of group A without significance. CONCLUSIONS: (1) Systemic administration of FK506 (1 mg/kg) showed neuroprotective and neurotrophic effect, which can facilitate nerve regeneration and promote functional recovery. (2) Local administration of FK506 (1 microg/ml) showed some extent of neuroprotective effect at early period of nerve injury, but the neurotrophic function is uncertain and still needs to be studied further.

[An experimental study of the neuroprotective effect of FK506 on acute spinal cord injury in dogs].

OBJECTIVE: To explore the neuroprotective effect of FK506 on acute spinal cord injury in dogs. METHODS: Acute spinal cord injury model was made with the Allen technique. Animals were randomly divided into 3 groups. Group A (n = 8) was the control group and received operation but no therapy, while group B and C (n = 8) received a single dose of FK506 (0.18 mg/kg and 0.3 mg/kg, respectively) administered with an arterial duct 2 h after spinal cord injury (SCI). Spine MRI, neurological function, histopathological examination of injured spinal cord and immunohistochemical examination of expression of NF(200) in neurons and GFAP in astrocytes were assessed at certain time after injury. RESULTS: Neurological function score of group C and B was better than that of group A (P < 0.05), with significance between group C and A, while no significance between group B and A statistically. The signal scope of spinal cord injury on MRI in group C was the smallest among all the groups, and the signal scope in group B was smaller than that in group A, which was directively associated with the neurological outcome. The expression of NF and GFAP was significantly higher in group C than in group A (P < 0.05), but without statistical significance between group B and A. CONCLUSION: Local administration of FK506 (0.3 mg/kg) possesses neuroprotective effect on acute spinal cord injury, which can improve neurological function recovery and attenuate secondary spinal cord injury. Local administration of FK506 possesses a dosage-effect relation.