BACKGROUND:Dural repair materials in current application mainly include autologous tissue repair material, alograft material, heterogeneous biological material and synthetic material, most of which are imported products with expensive price. OBJECTIVE: To evaluate safety and efficacy of a new biological type dura mater patch made in China based on animal experiments. METHODS:Bilateral dura mater defect models were established in 24 healthy domestic dogs: on the left side of the implant model, a new type biological dura patch was transplanted as experimental group; on the right side, another brand artificial dura patch that was on sale was transplanted as control group. After 1, 3, 6 and 12 months of implantation, we compared degradation, angiogenesis, growth and surrounding tissue reaction of dural substitutes of the experimental group and control group by hematoxylin-eosin staining, detected residual dose of epoxy-cross-linked agent in dogs’ blood and cerebrospinal fluid by fluorescence spectrophotometry. RESULTS AND CONCLUSION: During 1-12 months of implantation, al dogs grew wel and no infection or motor disorder was observed. Pathological examination showed that dura substitutes of the experimental group and control group had good biocompatibility, no or slightly inflammatory response. After 6 months of implantation, the surface of the new biological dural substitute (experimental group) was degraded and became a transit-state biomaterial with surrounding tissue, but the control group materials showed no degradation. After 12 months of implantation, the dura patch in the experimental group degraded nearly 50%, which appeared with neovascularization; while, the dura patch in the control group degraded 30%, and neovascularization was observed in only a smal amount of samples. Epoxy compounds of cross-linked agent were not detected in dogs’ blood and cerebrospinal fluid after 1, 3, 7 and 14 postoperative days. These findings show that this new type of biological dural substitute is a safe and effective dural repair material.

Objective: To clarify the status of proliferation and differentiation of RCJ3.1C5.18 cells in chondrogenesis and explore insulin-like growth factor binding proteins (Igfbps) gene expression profile during the process. The results provided a research foundation for understanding the role of Igfbps in chondrogenesis. Methods: Fetal rat derived mesenchymal chondrogenic cell line RCJ3.1C5.18 was used, which progresses spontaneously to differentiated growth plate chondrocytes. The proliferation and differentiation status of cells were determined by cell staining, real-time PCR and Muse™ Cell Analyzer at days 1, 4, 7 and 10 of culture respectively. Igfbps gene expression was assessed by real-time PCR. Results: In the early period (1-4 days), cells proliferated rapidly and the expression of chondrocytes marker genes, such as typeⅡ collagen, SRY-box 9 and aggrecan increased gradually. Igfbp4 and Igfbp6 gene expression paralleled the expression of chondrocytes marker genes. On days 7-10 of culture, cells viability decreased and gradually developed hypertrophic-like and osteogenic-like characteristics, which was confirmed by specific staining and gene expression of alkaline phosphatase, matrix metallopeptidase 13.Igfbp1, Igfbp3 and Igfbp5 mRNA levels were up regulated gradually at this stage. Conclusions The status of proliferation and differentiation of cells are different in the process of chondrogenesis. Changes in Igfbp gene expression are associated with chondrocyte differentiation, suggesting that they have different role during chondrocyte proliferation and differentiation.

Fluorosis is an endemic disease caused by prolonged exposure to excessive fluoride and is considered a serious public health problem in many countries. In recent years, the damage of chronic fluorosis to the central nervous system has attracted extensive attention from scholars at home and abroad. The mechanisms of neurotoxicity caused by fluorosis include oxidative stress, inflammatory reaction, autophagy, neurotransmitters and related enzymes, changes in neural signaling pathways, abnormal neuronal energy metabolism of neurons, cell apoptosis, etc., causing permanent damage to human brain structure, impaired learning ability, memory dysfunction and behavioral problems. This article reviews the effects of fluorosis on the nervous system and related mechanisms, and provides a reliable basis for prevention and treatment of fluorosis.

When partial nephrectomy is performed by posterior abdominal approach, the surgical field is poorly exposed, resulting in increased surgical difficulty and risk of injury.In this study, 28 patients with T 1a stage kidney tumors underwent retroperitoneal laparoscopic partial nephrectomy. Intraoperatively, exposure of the surgical field was achieved using the percutaneous puncture of the renal fascia suspension technique. There were no dissatisfactory exposures due to peritoneal damage during the surgery, no additional tubes were inserted, and no conversions to open surgery were needed. The operation time was (76.5±20.3) minutes, blood loss was (92.1±18.7) ml, renal artery clamping time was (19.5±4.3) minutes. Postoperatively, there were no complications such as bleeding, infection, or hematuria.

Objective To observe the effect of resistance breathing training on breast cancer related lymphedema. Methods Sixty breast cancer patients with lymphedema after operation from October, 2013 to April, 2015 were randomly divided into control group (n=30) and experiment group (n=30). The control group received routine rehabilitation and manual lymphatic drainage, while the experiment group received resistance breathing training in addition, for four weeks. Their flow of lymph was measured with emission computer tomography (ECT), and their upper arm circumferences were measured, their upper limb volumes were measured with water displacement before and after treatment. Results The flow of lymph increased in both groups after treatment (t>3.446, P<0.05), while the difference of bilateral upper arm circumferences (t>2.143, P<0.05) and upper limb volumes (t>1.562, P<0.05) reduced, and all the indices improved more in the experiment group than in the control group (t>1.982, P<0.05). Conclusion Resistance breathing training may increase the back flow of lymph, to relieve the lymphedema of injured extremity.

ObjectiveTo study the prevalence of depression and the related influencing factors among the frontline healthcare professionals in the prevention and control of risk of imported COVID-19 cases， so as to provide references for improving their mental health status. MethodsBased on Wenjuanxing platform， a total of 984 frontline healthcare professionals participating in the screening and treatment of imported COVID-19 cases in Beijing Xiaotangshan hospital were assessed using Patients’ Health Questionnaire Depression Scale-9 item（PHQ-9）. ResultsA total of 770 questionnaires were collected with a valid rate of 78.3%， among which 344 cases （44.7%） had depressive symptoms. Logistic regression analysis showed that great changes in work content （OR=2.206， P<0.01）， sleep deprivation （OR=2.359， P<0.01）， six hours or less of sleep （OR=2.032， P<0.05）， focusing on epidemic information more than 1 hour per day （OR=1.095， P<0.05） were risk factors for depression， and regular exercise （OR=0.473， P<0.01） was a protective factor for depression relief. ConclusionThe frontline healthcare professionals in the prevention and control of risk of imported COVID-19 cases suffer a high risk of depression， while measures including scientific shift system， adequate sleep， less attention to the epidemic， and regular exercise may be effective in maintaining their physical and mental health.