Systematic evaluation of the incidence of the knee donor area after autobone cartilage mosaic xentoplasty / 中国骨伤

OBJECTIVE@#To provide an overview of the incidence of knee donor -site morbidity after autologous osteochondral mosaicplasty.@*METHODS@#A comprehensive search was conducted in PubMed, EMbase, Wanfang Medical Network, and CNKI databases from January 2010 to April 20, 2021. Relevant literature was selected based on predefined inclusion and exclusion criteria, and data were evaluated and extracted. The correlation between the number and size of transplanted osteochondral columns and donor-site morbidity was analyzed.@*RESULTS@#A total of 13 literatures were included, comprising a total of 661 patients. Statistical analysis revealed an incidence of knee donor-site morbidity at 8.6% (57/661), with knee pain being the most common complaint, accounting for 4.2%(28/661). There was no significant correlation between the number of osteochondral columns and postoperative donor-site incidence (P=0.424, N=10), nor between the diameter size of osteochondral columns and postoperative donor-site incidence(P=0.699, N=7).@*CONCLUSION@#Autologous osteochondral mosaicplasty is associated with a considerable incidence of knee donor-site morbidity, with knee pain being the most frequent complaint. There is no apparent correlation between donor-site incidence and the number and size of transplanted osteochondral columns. Donors should be informed about the potential risks.

Cardiometabolic disease patterns among elderly patients with colorectal cancer in China / 中华肿瘤杂志

Objective: To explore the distribution patterns of cardiometabolic diseases (CMD) in elderly patients with colorectal cancer, and provide a reference for the prevention and treatment of cardiovascular metabolic diseases in these patients. Methods: Clinical data of 3 894 elderly patients with colorectal cancer from January 2008 to March 2018 admitted in the Chinese PLA General Hospital were recruited and the incidence rate of CMD was retrospectively analyzed. The influence factors of elderly patients with colorectal cancer combined with CMD were analyzed by multivariate Logistic regression model. Results: The morbidity rate of CMD in elderly patients with colorectal cancer is 33.4% (1 301/3 894), among them, the morbidity rate of the male was 31.9% (768/2 409), and that of the female was 35.9% (533/1 485). There was not significant difference between these two sex (P=0.074). The morbidity rates of CMD in patients of 65-74 years, 75-84 years and ≥85 years were 30.6% (754/2 462), 37.0% (479/1 294) and 49.3% (68/138), respectively, with significant differences (P<0.001). Multiple Logistic regression analysis revealed that female (OR=1.213, 95%CI: 1.056-1.394), age (75-84 years group: OR=1.344, 95%CI: 1.164-1.552; ≥85 years group: OR=2.345, 95%CI: 1.651-3.331) and body mass index (BMI 18.5-24.9 kg/m(2) group: OR=1.319, 95%CI: 1.065-1.638; ≥25 kg/m(2) group: OR=2.041, 95%CI: 1.627-2.561) were independent risk factors for elderly colorectal cancer patients with CMD. Conclusion: The morbidity rate of CMD in elderly patients with colorectal cancer increases with age and it is urgent to strengthen multidisciplinary cooperation and develop reasonable treatment plans to extend the survival and life quality of these patients.

Clinical effects of arthroscopy-assisted anterior cruciate ligament tibial eminence avulsion fracture compared with traditional open surgery:a Meta-analysis / 中国骨伤

OBJECTIVE@#To systematically evaluate the clinical efficacy of arthroscopy and traditional incision in the treatment of tibial avulsion fracture of anterior cruciate ligament (ACL).@*METHODS@#From July 2010 to July 2020, clinical comparative trial about arthroscopy and traditional incision in the treatment of ACL tibial avulsion fracture was conducted by using computer-based databases, including Embase, Pubmed, Central, Cinahl, PQDT, CNKI, Weipu, Wanfang, Cochrane Library, CBM. Literature screening and data extraction were carried out according to the inclusion and exclusion criteria, and the quality of the included literature was evaluated by improved Jadad score and Ottawa Newcastle scale (NOS). The operation time, hospital stay, fracture healing time, knee range of motion, postoperative excellent and good rate, complication rate, Lysholm score, International Knee Documentation Committee (IKDC) score and Tegner score were statistically analyzed by Review Manager 5.3 software.@*RESULTS@#Finally, 16 literatures were included, including 1 randomized controlled trial and 15 non randomized controlled trials, with a total of 822 patients (405 in arthroscopy group and 417 in traditional incision group). Meta analysis showed that the operation time [MD=-9.03, 95% CI(-14.36, -3.70), P<0.001], hospital stay [MD=-5.81, 95%CI(-9.32, -2.31), P=0.001] and fracture healing time [MD=-14.61, 95% CI(-17.93, -11.28), P<0.001] in the arthroscopy group were better than those in the traditional incision group. The incidence of complications in arthroscopy group was lower than that in traditional incision group[OR=0.15, 95%CI(0.07, 0.33), P<0.001]. The postoperative excellent and good rate[OR=4.39, 95%CI (1.96, 9.82), P<0.001], knee mobility[MD=6.78, 95%CI(2.79, 10.77), P<0.001], Lysholm score[MD=11.63, 95%CI(4.91, 18.36), P<0.001], IKDC score[MD=7.83, 95%CI(6.09, 9.57), P<0.001] and Tegner score[MD=0.60, 95%CI(0.31, 0.89), P<0.001] in the arthroscopic group were higher than those in the traditional incision group.@*CONCLUSION@#Compared with the traditional open reduction and internal fixation, arthroscopic surgery in patients with ACL tibial avulsion fracture can shorten the operation time, hospital stay and fracture healing time, reduce the incidence of postoperative complications, and obtain good postoperative knee function. It can be recommended as one of the first choice for patients with ACL tibial avulsion fracture.

Conversion of serum anti-Schistosoma japonicum antibodies detected by immunological tests following treatment with praziquantel: a meta-analysis / 中国血吸虫病防治杂志

Objective To evaluate the conversion of serum antibodies against Schistosoma japonicum in humans and livestock detected by immunological tests following treatment with praziquantel. Methods The studies pertaining to serological tests of schistosomiasis japonica published from 1991 to 2020 were retrieved in electronic databases, including Chinese National Knowledge Infrastructure, WanFang Data, PubMed and ScienceDirect. Data were extracted from included studies. The publication bias was assessed with funnel plots using the software RevMan version 5.3, and the conversion of antibodies against S. japonicum was evaluated through meta-analysis. Results A total of 40 publications were included in the final meta-analysis, consisting of 33 Chinese publications and 7 English publications, and all immunological tests were performed with indirect hemagglutination test (IHA) and enzyme-linked immunosorbent assay (ELISA). Pooled analysis showed that the negative rates of serum anti-S. japonicum antibody were 45.36% [95% confidential interval (CI): (43.96%, 46.76%)] and 20.83% [95% CI: (19.69%, 21.97%)] detected by ELISA and IHA within 6 months post praziquantel treatment, 62.95% [95% CI: (61.59%, 64.31%)] and 55.61% [95% CI: (54.21%, 57.01%)] within 6 to 12 months after treatment and 85.92% [95% CI: (84.94%, 86.90%)] and 86.90% [95% CI: (85.95%, 87.85%)] over 12 months after treatment, respectively. Conclusions The negative rate of the serum anti-S. japonicum antibody by IHA and ELISA increased with the time of post-treatment with praziquantel. The overall negative rates of anti-S. japonicum antibody detected by IHA and ELISA are low within 12 months post praziquantel treatment. However, a high negative rate of anti-S. japonicum antibody is detected if there is no new contact with infested water after 12 months of praziquantel treatment.

Cognitive and willngness to EV71 vacci natior among parents for children in Dongming District of Pudong / 中国学校卫生

Objective@#To understand cognition and willingness of EV71 vaccination among parents of children, so as to provide scientific basis for vaccination.@*Methods@#A cross-sectional survey (census) was adopted. A questionnaire survey was conducted among parents of 2 783 preschool children from 12 kindergartens to analyze the parents’ cognition towards EV71 vaccine and willingness of vaccination of EV71 vaccine.@*Results@#Among the 2 783 parents surveyed, 1 843 heard of EV71 vaccine. The parents’ awareness rate of EV71 vaccine was 51.9%. The main source of EV71 vaccinerelated information was obtained through hospitals(n=887), followed by schools(n=752). 1 014 received EV71 vaccine. The main reason of EV71 vaccination was that vaccine was believed to be effective in preventing hand,foot and mouth disease(HFMD) (76.1%), while the main reason for unwillingness for vaccination was lack of knowledge(31.7%). And 2 478 considered that EV71 vaccine should be included in planned immunization. Multivariate Logistic regression analysis showed that children in public schools(OR=0.72, 95%CI=0.59-0.89), mothers from urban residents(OR=0.76, 95%CI=0.64-0.90), parents lack of EV71 vaccine awareness(OR=0.42,95%CI=0.35-0.49), and perceived high price of EV71 vaccine (OR=0.66, 95%CI=0.47-0.92) had a low vaccination rate. Higher EV71 vaccination rate was related to children’ status as baby class (OR=2.55,95%CI=1.18-5.52),bottom class (OR=2.24,95%CI=1.54-3.24) and middle class(OR=1.51, 95%CI=1.05-2.15)(P<0.05).@*Conclusion@#EV71 vaccination in preschool children in our jurisdiction was relatively high. School type, mother’s household registration, children’s grade and the parental percption of EV71 vaccine price are the main factors influencing EV71 vaccine vaccination in preschool children.

Material properties and clinical application status of Biodentine / 口腔疾病防治

@#Biodentine is a bioactive dentin replacement material whose main component is high-purity tricalcium silicate without dicalcium silicate. It has a shorter cure time; although it has a higher solubility, it hardly affects the volume of the material. It has a low X-ray barrier property, low porosity, high bulk density, and high compressive strength and is not affected by moisture or a dry environment. It has strong acid corrosion resistance, can increase dentin resistance, and has biocompatibility due to the lack of cytotoxicity. It has antibacterial activity against various bacteria, with strong antibacterial activity against Streptococcus sanguis. Since 2010, Biodentine has been widely used in clinical treatments such as dental restoration, pulp capping, pulpectomy, et al. In clinical applications, Biodentine is primarily used as a permanent dentin substitute or as a temporary enamel substitute within 6 months. As a new dentin substitute material with a short clinical application time, the long-term efficacy of Biodentine requires further follow-up observation studies.

Xylanase gene mutation by error-prone pcr and expression in Pichia pastoris / Mutação do gene da xilanase por pcr propensa a erros e expressão em Pichia pastoris

Xylanase can hydrolyze xylan for reducing its anti-nutritional impact and improving nutrient availability, so obtaining suitable xylanase to degrade xylan is essential. Error-prone PCR and gene transformation were used in this study to obtain the ideal xylanase for degrading xylan effectively. The result showed that one mutant xylanase gene with high xylanase expression was obtained. After the mutant xylanase gene was connected with pGAPZA and transformed into Pichia pastoris (P. pastoris), the recombinant P. pastoris with mutant gene was found to produce higher xylanase activity (0.1480 U/mL) than that with the native xylanase gene (0.1360 U/mL) after 12 h incubation (p<0.05). The optimal temperature and pH of xylanase expressed by native and mutant genes were the same, i.e. 40°C and 5.50 (p<0.05). In addition, adding 0.2% Tween 80 during recombinant P. pastoris incubation could significantly increase xylanase yield by about 30-35% (p<0.05). The mutant xylanase could significantly increase xylose yield from wheat meal more than the native xylanase (p<0.05).

A xilanase pode hidrolisar o xilano para reduzir seu impacto antinutricional e melhorar a disponibilidade de nutrientes, portanto, obter xilanase adequada para degradar o xilano é essencial. A PCR propensa a erros e a transformação genética foram utilizadas neste estudo para obter a xilanase ideal para degradar eficazmente a xilana. O resultado mostrou que um gene mutante de xilanase com alta expressão de xilanase foi obtido. Depois que o gene mutante da xilanase foi conectado ao pGAPZA e transformado em Pichia pastoris (P. pastoris), o recombinante P. pastoris com o gene mutante produziu maior atividade de xilanase (0,1480 U / mL) do que com o gene nativo da xilanase (0,1360 U / mL) após 12 h de incubação (p <0,05). A temperatura e o pH ótimos da xilanase expressa pelos genes nativos e mutantes foram os mesmos, ou seja, 40 ºC e 5,50 (p <0,05). Além disso, a adição de Tween 80 a 0,2% durante a incubação de P. pastoris recombinante poderia aumentar significativamente o rendimento de xilanase em cerca de 30-35% (p <0,05). A xilanase mutante poderia aumentar significativamente o rendimento de xilose da farinha de trigo mais do que a xilanase nativa (p <0,05).

The hepatic ectonucleotide pyrophosphatase/phosphodiesterase 1 gene mRNA abundance is reduced by insulin and induced by dexamethasone

Hormones regulate hepatic gene expressions to maintain metabolic homeostasis. Ectonucleotide pyrophosphatase/phosphodiesterase 1 has been thought to interfere with insulin signaling. To determine its potential role in the regulation of metabolism, we analyzed its gene (Enpp1) expression in the liver of rats experiencing fasting and refeeding cycles, and in primary rat hepatocytes and human hepatoma HepG2 cells treated with insulin and dexamethasone using northern blot and real-time PCR techniques. Hepatic Enpp1 expression was induced by fasting and reduced by refeeding in the rat liver. In primary rat hepatocytes and HepG2 hepatoma cells, insulin reduced Enpp1 mRNA abundance, whereas dexamethasone induced it. Dexamethasone disrupted the insulin-reduced Enpp1 expression in primary hepatocytes. This is in contrast to the responses of the expression of the cytosolic form of phosphoenolpyruvate carboxykinase gene to the same hormones, where insulin reduced it significantly in the process. In addition, the dexamethasone-induced Enpp1 gene expression was attenuated in the presence of 8-Br-cAMP. In conclusion, we demonstrated for the first time that hepatic Enpp1 is regulated in the cycle of fasting and refeeding, a process that might be attributed to insulin-reduced Enpp1 expression. This insulin-reduced Enpp1 expression might play a role in the development of complications in diabetic patients.

miR-429 promotes capecitabine-resistance in pancreatic cancer PANC-1 cells by down-regulating PTEN and activating PI3K/AKT signaling pathway / 中国肿瘤生物治疗杂志

@# Objective: To explore the mechanism of miR-429 targeting PTEN to affect capecitabine-resistance in pancreatic cancer PANC-1 cells though the PI3K/AKT signaling pathway. Methods: Capecitabine-resistant pancreatic cancer cell line PANC-1/CAP was constructed, and the expression of miR-429 and PTEN were detected by quantitative Real-time polymerase chain reaction (qRT-PCR) and Western blotting. The effect of miR-429 knock-down on cell proliferation viability, apoptosis and capecitabine-resistance was measured by colony formation assay, CCK-8 assay andAnnexin V-FITC/PI double staining flow cytometry assay, respectively. Subsequently, dual luciferase reporter assay verified that PTEN was a target gene of miR-429. Furthermore, the effect of miR-429 on PTEN-PI3K/ AKT signaling pathway was measured by Western blotting. Results: miR-429 was found to be up-regulated in PANC-1 cells and PANC-1/CAP cells compared with the non-malignant pancreatic ductal cell line (HPDE6-C7) (P<0.05 or P<0.01). Moreover, silencing of miR-429 significantly decreased cell proliferation viability, capecitabine-resistance and enhanced apoptosis of PANC-1/CAP cells; additionally, dual luciferase reporter assay confirmed that PTEN was a target of miR-429 (P<0.05 or P<0.01). Suppression of miR-429 up-regulated PTEN and blocked the PI3K/AKT signaling pathway to decrease cell proliferation viability and further reduce the capecitabine-resistance of PANC-1/CAP cells (P<0.05 or P<0.01). Conclusion: miR-429/PTEN-PI3K/AKT signaling pathway plays a certain role in regulating the capecitabine-resistance of pancreatic cancer, and inhibition of miR-429 expression may reverse the resistance of PANC-1/CAPto capecitabine.

Survey of traditional Dai medicine reveals species confusion and potential safety concerns: a case study on Radix Clerodendri Japonicum / 中国天然药物

The adulteration of herbal products is a threat to consumer safety. In the present study, we surveyed the species composition of commercial Radix Clerodendri Japonicum products using DNA barcoding as a supervisory method. A reference database for plant-material DNA-barcode was successfully constructed with 48 voucher samples from 12 Clerodendrum species. The database was used to identify 27 Radix Clerodendri Japonicum decoction piece samples purchased from drug stores and hospitals. The DNA sequencing results revealed that only 1 decoction piece (3.70%) was authentic C. japonicum, as recorded in the Dai Pharmacopeia, whereas the other samples were all adulterants, indicating a potential safety issue. The results indicate that decoction pieces that are available in the market have complex origins and that DNA barcoding is a suitable tool for regulation of Dai medicines.

A short term clinical study of fibular osteotomy for knee osteoarthritis / 中国骨伤

<p><b>OBJECTIVE</b>To study clinical effects of fibular osteotomy for the treatment of knee osteoarthritis.</p><p><b>METHODS</b>From January 2015, 12 patients (15 knees) with knee osteoarthritis were treated with fibular osteotomy. The main symptom was interval inside pain. All the patients were female with an average age of 61.3 years old. Early postoperative ambulation of joints was carried out after surgery, and the corresponding radiographic assessment before and after operations were performed with record. Finally, the following indicators were analyzed:VAS, KSS, HSS, respectively before, 2 days and 2 months after the operation.</p><p><b>RESULTS</b>The average hospitalization time was (6.0±2.4) days, and the time of unilateral operation was (33.3±8.4) minutes without significant bleeding. There were no obvious complications such as wound infection, delayed healing and nerve damage. All the patients could walk around 1 day after operations with a chief complaint of the obvious reduction or disappear of the interval medial knee pain. The VAS score, HSS score and KSS clinical score were significantly improved 2 days after surgery compared to the scores before operation. These above scores and functional score were significantly improved 2 months after operation compared to the scores before operation. X ray films of the weight bearing knees were taken 2 days after surgery, showing increased height of medial joint space to some extent compared to that before operation.</p><p><b>CONCLUSIONS</b>A fibular osteotomy has been proved to significantly reduce the postoperative pain and facilitate the good recovery of joint function with the advantages of simple surgical procedures and slighttrauma. Therefore, it is an effective method for the treatment of knee osteoarthritis with varus deformity.</p>

Protease gene shuffling and expression in Pichia pastoris

Four kinds of neutral and alkaline protease genes from Aspergillus oryzae and Bacillus subtilis were isolated and shuffled. The shuffled genes were selected, inserted into pGAPZαA plasmid and transformed into Escherichia coli. The gene which could express high-activity protease was selected by screening the sizes of transparent zones around the colonies on casein plates. After an ideal protease gene was selected, it was sequenced and then transformed into Pichia pastoris X33. The result showed that the base in 1022th position of shuffled protease gene was changed from thymine to cytosine, inferring that cysteine was changed to arginine in the mutant protease. After 48 h incubation for the transformed P. pastoris with the mutant or native protease genes, the mutant protease activity was 36.4% higher than the native protease (P<0.05). The optimal pH and temperature of the mutant protease were 6.5-8.0 and 30-70°C, respectively, which indicated better stability than the native protease (P<0.05).

Human amnion mesenchymal cells inhibit lipopolysaccharide-induced TNF-α and IL-1ß production in THP-1 cells

BACKGROUND: Human amnion mesenchymal cells (hAMCs), isolated from the amniotic membrane of human placenta, are a unique population of mesenchymal stem cells. Recent studies demonstrated that hAMCs could inhibit the activities and functions of several immune cells. However, their effect on inflammatory macrophages is largely unknown. This study investigated the effect of hAMCs on expression of inflammatory cytokines and mitogen-activated protein kinases (MAPKs)/NF-kB pathway in human THP-1 macrophages induced by lipopolysaccharide (LPS). RESULTS: The levels of TNF-α and IL-1ß secreted by LPS- stimulated THP-1 cells were increased significantly compared with those in the control group. After co-culture with different numbers of hAMCs, the levels of TNF-α and IL-1ß in LPS-stimulated THP-1 cells were significantly reduced compared with the LPS group. The mRNA expression of TNF-α and IL-1ß were also markedly inhibited. Moreover, treating LPS-stimulated THP-1 cells with hAMCs supernatants could also suppress TNF-α and IL-1ß production in THP-1 cells. Important signaling pathways involved in the production of TNF-α and IL-1ß were affected by hAMCs co-culture: hAMCs remarkably suppressed NF-kB activation and down-regulated the phosphorylation of ERK and JNK in LPS- stimulated THP-1 cells. CONCLUSIONS: Human amnion mesenchymal cells inhibited the production of TNF-α and IL-1ß secreted by LPS-stimulated THP-1 cells, partly through the suppression of NF-kB activation and ERK and JNK phosphorylation.

Research on pericellular matrix properties for chondrcytes / 中国骨伤

Pericellular matrix (PCM) is a narrow tissue region surrounding chondrocytes, which "chondron" with its enclosed cells. A number of studies suggested that PCM is rich in proteoglycans, collagen and fibronectin, and plays an important role in regulating microenvironment of chondrocytes. Direct measures of PCM properties through micropipette aspiration technique showed that PCM was different from mechanical property of chondrocytes and nature extracellular matrix. However, the function of PCM is not clear, and need further study.

Massive and painful ascites as a presenting manifestation of systemic lupus erythematosus flare: a case report and literature review / Ascitis dolorosa y masiva como forma de presentación de una reactivación lúpica: Presentación de un caso

Lupus peritonitis (LP) is extremely rare. Acute LP is characterized by rapid onset of ascites and severe abdominal pain, in addition to other well-recognized clinical features of a general systemic lupus erythematosus (SLE) fare. Ascites associated with acute LP has been rarely reported as the prominent feature of a SLE fare. We report a 39-year-old woman who developed massive, painful ascites as the presenting manifestation of a SLE fare. Diagnostic workup ruled out the possibility of hepatic, cardiovascular, infectious, or malignant diseases, and confirmed the presence of a SLE fare. The patient was treated with methyl prednisolone and hydroxychloroquine resulting in dramatic improvement of her condition. During ambulatory follow up, she has remained asymptomatic up to the moment of this writing. Adrenal steroids and hydrocychloroquine may be useful for the management of SLE fares in patients with massive, painful ascites due to acute LP.

La peritonitis lúpica es rara. El cuadro agudo se caracteriza por ascitis de comienzo rápido, dolor abdominal severo y otras manifestaciones de una recidiva de un lupus eritematoso sistémico (LES). Sólo ocasionalmente e ha informado que la ascitis y peritonitis lúpica sean las principales manifestaciones de una recidiva lúpica. Presentamos a una mujer de 39 años que presentó ascitis masiva y dolorosa como la primera manifestación de una reactivación lúpica. El estudio diagnóstico descartó problemas hepáticos, pulmonares, cardiacos, cáncer o infecciones y confirmó la reactivación lúpica. La paciente se trató con metilprednisolona y cloroquina, resultando en una mejoría dramática. Al momento de preparar este informe, la paciente permanece asintomática en control ambulatorio. Los corticoides y cloroquina pueden ser medicamentos útiles para el tratamiento de pacientes con ascitis dolorosa y masiva secundaria a peritonitis lúpica.

Application of Factor Analysis in study on dose-effect relationship in traditional Chinese medicine prescription / 中草药

Objective: By taking classical prescription of Gegen Qinlian Decoction (GQD) as the example, this research aims at studying the law of change between the clinical dosage of Chinese medicine and its effect. Methods: The test groups were divided into nine groups according to nine different dosages of GQD (1.65-28.05 g/kg). Each group was given the same dosage for six times. Then the factors of serum protein, blood sugar, insulin, glycated hemoglobins, and insulin resistance index were extracted. Results: Two common factors were extracted and the variance contribution rates were 55.601% and 24.157%, respectively. The first factor could represent blood sugar, glycated hemoglobins, and insulin resistance index, while the second factor could represent serum protein and insulin. Conclusion: Through analyzing the experimental data of GQD in the treatment of diabetes mellitus, it is found that Factor Analysis can achieve better results in eliminating the interference from human factors. Therefore, Factor Analysis is an effective and suitable method for studying the dose-effect relationship of Chinese material medica in clinical therapy.

Enhancement of GABA-activated currents by arginine vasopressin in rat dorsal root ganglion neurons / 生理学报

A growing number of studies have shown that arginine vasopressin (AVP) plays an analgesia role in the modulation of nociception. Previous studies have focused on the central mechanisms of AVP analgesia. The aim of the present study was to find out whether peripheral mechanisms are also involved. The effect of AVP on GABA-activated currents (IGABA) and GABAA receptor function in freshly isolated dorsal root ganglion (DRG) neurons of rats were studied using whole cell patch clamp technique. The result showed that, IGABA were potentiated by pre-treatment with AVP (1 × 10⁻¹⁰-1 × 10⁻⁵ mol/L) in a concentration-dependent manner. Meanwhile, the GABA concentration-response curve was shifted upwards, with an increase of (49.1 ± 4.0)% in the maximal current response but with no significant change in the EC50 values. These results indicate that the enhancing effect is non-competitive. In addition, the effects of AVP on IGABA might be voltage-independent. This potentiation of IGABA induced by AVP was almost completely blocked by the V1a receptor antagonist SR49059 (3 × 10⁻⁶ mol/L). Also it could be removed by intracellular dialysis of either GDP-β-S (5 × 10⁻⁴mol/L), a non-hydrolyzable GDP analog, or GF109203X (2 × 10⁻⁶ mol/L), a selective protein kinase C (PKC) inhibitor, with the re-patch clamp. These results suggest that AVP up-regulates the function of the GABAA receptor via G protein-coupled receptors and PKC-dependent signal pathways in rat DRG neurons, and this potentiation may underlie the analgesia induced by AVP.

Identification of microRNAs and mRNAs associated with multidrug resistance of human laryngeal cancer Hep-2 cells

Multidrug resistance (MDR) poses a serious impediment to the success of chemotherapy for laryngeal cancer. To identify microRNAs and mRNAs associated with MDR of human laryngeal cancer Hep-2 cells, we developed a multidrug-resistant human laryngeal cancer subline, designated Hep-2/v, by exposing Hep-2 cells to stepwise increasing concentrations of vincristine (0.02-0.96'µM). Microarray assays were performed to compare the microRNA and mRNA expression profiles of Hep-2 and Hep-2/v cells. Compared to Hep-2 cells, Hep-2/v cells were more resistant to chemotherapy drugs (∼45-fold more resistant to vincristine, 5.1-fold more resistant to cisplatin, and 5.6-fold more resistant to 5-fluorouracil) and had a longer doubling time (42.33±1.76 vs 28.75±1.12'h, P<0.05), higher percentage of cells in G0/G1 phase (80.98±0.52 vs 69.14±0.89, P<0.05), increased efflux of rhodamine 123 (95.97±0.56 vs 12.40±0.44%, P<0.01), and up-regulated MDR1 expression. A total of 7 microRNAs and 605 mRNAs were differentially expressed between the two cell types. Of the differentially expressed mRNAs identified, regulator of G-protein signaling 10, high-temperature requirement protein A1, and nuclear protein 1 were found to be the putative targets of the differentially expressed microRNAs identified. These findings may open a new avenue for clarifying the mechanisms responsible for MDR in laryngeal cancer.

Normal age-related viscoelastic properties of chondrons and chondrocytes isolated from rabbit knee / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The mechanical microenvironment of the chondrocytes plays an important role in cartilage homeostasis and in the health of the joint. The pericellular matrix, cellular membrane of the chondrocytes, and their cytoskeletal structures are key elements in the mechanical environment. The aims of this study are to measure the viscoelastic properties of isolated chondrons and chondrocytes from rabbit knee cartilage using micropipette aspiration and to determine the effect of aging on these properties.</p><p><b>METHODS</b>Three age groups of rabbit knees were evaluated: (1) young (2 months, n = 10); (2) adult (8 months, n = 10); and (3) old (31 months, n = 10). Chondrocytes were isolated from the right knee cartilage and chondrons were isolated from left knees using enzymatic methods. Micropipette aspiration combined with a standard linear viscoelastic solid model was used to quantify changes in the viscoelastic properties of chondrons and chondrocytes within 2 hours of isolation. The morphology and structure of isolated chondrons were evaluated by optical microscope using hematoxylin and eosin staining and collagen-6 immunofluorescence staining.</p><p><b>RESULTS</b>In response to an applied constant 0.3 - 0.4 kPa of negative pressure, all chondrocytes exhibited standard linear viscoelastic solid properties. Model predictions of the creep data showed that the average equilibrium modulus (E(∞)), instantaneous modulus (E(0)), and apparent viscosity (m) of old chondrocytes was significantly lower than the young and adult chondrocytes (P < 0.001); however, no difference was found between young and adult chondrocytes (P > 0.05). The adult and old chondrons generally possessed a thicker pericellular matrix (PCM) with more enclosed cells. The young and adult chondrons exhibited the same viscoelastic creep behavior under a greater applied pressure (1.0 - 1.1 kPa) without the deformation seen in the old chondrons. The viscoelastic properties (E(∞), E(0), and m) of young and adult chondrons were significantly greater than that observed in young and adult cells, respectively (P < 0.001). The adult chondrons were stiffer than the young chondrons under micropipette aspiration (P < 0.001).</p><p><b>CONCLUSIONS</b>Our findings provide a theoretical model to measure the viscoelastic properties of the chondrons as a whole unit by micropipette aspiration, and further suggest that the properties of the chondrocytes and PCM have an important influence on the biomechanical microenvironment of the knee joint cartilage degeneration that occurs with aging.</p>

Aerobic biodegradation of nonylphenol ethoxylates in shaking-flask test

Nonylphenol ethoxylates (NPEOs), which are widely used for industrial and domestic purposes, exert adverse effects on wildlife after being used and discharged into the environment. However, their ultimate biodegradability and biodegradation pathway remains unclear. In this study, the aerobic degradability of nonylphenol ethoxylates (NPEOs) by the acclimated microorganisms in active sludge was examined using shaking-flask tests. The degradation of benzene rings in NPEOs was determined using UV spectroscopy and high performance liquid chromatography (HPLC). Results showed that more than 80 percent of benzene rings were removed after 8-10 days of degradation, and the majority of NPEOs were also removed after 9 days of degradation, indicating NPEOs and the benzene rings could be ultimately degraded by microorganisms in acclimated active sludge. Electrospray ionization-mass spectroscopy (ESI-MS) analysis of biodegradation intermediates indicate that stepwise omega, beta-oxidation of EO chains or fission of EO chains, and further omega, beta-oxidation of alkyl-chain for short-EO-chain NPEOs constitute the main pathway in the early stage, and complete biodegradation occur when the benzene rings in these molecules are opened in the later stage.