OBJECTIVETo explore a new method for the therapy of avascular necrosis of the femoral head.

METHODSThe recombinant plasmid pCD-hVEGF165 was mixed with collagen and was implanted in the necrotic femoral head. The expression of vascular endothelial growth factor (VEGF) was examined by RNA dot hybridization and immunohistochemical techniques. Repair of the femoral head was observed by histological and histomorphometric analysis.

RESULTSThe expression of VEGF was detected in the femoral head transfected with the VEGF gene. The femoral head transfected with the VEGF gene showed a significant increase in angiogenesis 2 and 4 weeks after gene transfection and a significant increase in bone formation 6 and 8 weeks after gene transfection on histomorphometric analysis (P < 0.01).

CONCLUSIONSTransfection of the VEGF gene enhances bone tissue angiogenesis. Repair of osteonecrosis could be accelerated accordingly, thus providing a potential method for therapy of osteonecrosis.

Animals ; Femur Head Necrosis ; therapy ; Neovascularization, Physiologic ; Rabbits ; Random Allocation ; Transfection ; Vascular Endothelial Growth Factor A ; genetics

To explore a new method for the therapy of the avascular necrosis of the femoral head, the recombinant plasmid pCD-hVEGF165 was mixed with collagen and was implanted in the necrotic femoral head. The expression of vascular endothelial growth factor (VEGF) was detected by RNA dot hybridization and immunohistochemical method. The repair of the femoral head was observed by histological method. The results showed that the expression of VEGF was detectable in the femoral head treated with VEGF gene. Angiogenesis in these femoral heads was more abundant than the control. Bone repairing was augmented in the femoral head treated with VEGF gene. The results suggest that angiogenesis in bone tissue could be augmented by gene transfection of VEGF and bone repairing would be accelerated accordingly.
Animals ; Collagen ; therapeutic use ; Femur Head ; blood supply ; Femur Head Necrosis ; therapy ; Gene Transfer Techniques ; Genetic Therapy ; Implants, Experimental ; Neovascularization, Physiologic ; Osteogenesis ; Plasmids ; genetics ; Rabbits ; Random Allocation ; Recombinant Proteins ; biosynthesis ; genetics ; Vascular Endothelial Growth Factor A ; biosynthesis ; genetics

OBJECTIVETo investigate the role of apoptosis in radiation-induced mouse thymus lymphocyte damage and repair and provide the basis for understanding the molecular mechanism of radiation-induced lymphocyte damage and repair as well as the prevention and treatment of acute radiation sickness.

METHODSWe studied the dynamic changes of apoptosis of mouse thymus lymphocytes and the expression of bax and bcl-2 gene products after 2, 4, 6 and 8 Gy of whole body gamma-irradiation using in situ terminal labeling, DNA electrophoresis and immunohistochemical techniques.

RESULTSAt the early stage after irradiation, the percentage of apoptotic lymphocytes increased rapidly in accordance with the increasing of radiation doses, while the counts of the thymus and peripheral lymphocytes decreased sharply, showing an opposite change to lymphocyte apoptosis. After 6 Gy gamma-irradiation, typical morphological characteristics of thymus apoptotic lymphocytes in early, middle and late stages were found by transmission electron microscopy. The thymus lymphocytes displayed characteristic DNA ladders 4 hr and 8 hr after 2-6 Gy gamma-irradiation,using DNA gel electrophoresis techniques. Abnormal expression of bcl-2 and bax gene products were shown in irradiated lymphocytes.

CONCLUSIONSApoptosis plays an important role in the process of radiation-induced mouse thymus lymphocyte damage and repair. Bcl-2 and Bax proteins may regulate the process of lymphocyte apoptosis.

Animals ; Apoptosis ; radiation effects ; Dose-Response Relationship, Radiation ; Gamma Rays ; Lymphocytes ; physiology ; radiation effects ; Male ; Mice ; Proto-Oncogene Proteins ; analysis ; Proto-Oncogene Proteins c-bcl-2 ; analysis ; Thymus Gland ; pathology ; radiation effects ; Time Factors ; bcl-2-Associated X Protein

Background: Cardiopulmonary resuscitation (CPR) strategies in COVID-19 patients differ from those in patients suffering from cardiogenic cardiac arrest. During CPR, both healthcare and non-healthcare workers who provide resuscitation are at risk of infection. The Working Group for Expert Consensus on Prevention and Cardiopulmonary Resuscitation for Cardiac Arrest in COVID-19 has developed this Chinese Expert Consensus to guide clinical practice of CPR in COVID-19 patients. Main recommendations: 1) A medical team should be assigned to evaluate severe and critical COVID-19 for early monitoring of cardiac-arrest warning signs. 2) Psychological counseling and treatment are highly recommended, since sympathetic and vagal abnormalities induced by psychological stress from the COVID-19 pandemic can induce cardiac arrest. 3) Healthcare workers should wear personal protective equipment (PPE). 4) Mouth-to-mouth ventilation should be avoided on patients suspected of having or diagnosed with COVID-19. 5) Hands-only chest compression and mechanical chest compression are recommended. 6) Tracheal-intubation procedures should be optimized and tracheal-intubation strategies should be implemented early. 7) CPR should be provided for 20-30 min. 8) Various factors should be taken into consideration such as the interests of patients and family members, ethics, transmission risks, and laws and regulations governing infectious disease control. Changes in management: The following changes or modifications to CPR strategy in COVID-19 patients are proposed: 1) Healthcare workers should wear PPE. 2) Hands-only chest compression and mechanical chest compression can be implemented to reduce or avoid the spread of viruses by aerosols. 3) Both the benefits to patients and the risk of infection should be considered. 4) Hhealthcare workers should be fully aware of and trained in CPR strategies and procedures specifically for patients with COVID-19.