Objective To observe the influence of low or middle power microwave radiation on tissues adja-cent to titanium alloy implants. Methods Titanium alloy internal fixation plates were implanted into the upper femur of the right side of New Zealand white rabbits, the left femurs served as the control. Then the femurs were exposed to 20, 40, 60, or 80 W of microwave radiation at a frequency of 2450 MHz for 30 minutes, and real-time temperature of the implants and its adjacent muscles were recorded. The nerve conduction study of the sciatic nerve was performed by stimulating the nerve and recording from gastrocnemius in both groups. Finally, all the rabbits were sacrificed and histo-logical studies were performed on nerve and muscle sections. Results Compared to the control limbs, temperatures of limbs with titanium alloy implants increased significantly when exposed to microwave radiation at 60 and 80 W ( P<0.05) but no significant differences were revealed when exposed to radiation at 20 and 40 W ( P<0.05) . For the sciatic nerve conduction, significantly prolonged distal latency of CMAP ( P<0.05) and slower nerve conduction velocity ( P<0.05) were observed in the experimental limbs when exposed to microwave radiation at 60 and 80 W, but the decrease of CMAP amplitude was not significant (P>0.05). Pathological examination showed obvious congestion and bleeding in the intercellular spaces of skeletal muscle cells in the experiment group when exposed to radiation at 60 W, with no ob-vious pathological changes found in the sciatic nerve. However, when exposed to radiation at 80 W, vacuoles appeared in myocytes, the cellular structure was destroyed and the myelin sheath of the sciatic nerve swelled. Conclusion Ex-posure to microwave irradiation at 20 and 40 W, but not 60 and 80 W exerts no adverse effects on nerves and muscles adjacent to titanium alloy internal fixation plates. Consequently, continuous wave microwave irradiation at low powers (20~40 W) is a safer auxiliary treatment for limbs with titanium alloy implants.

A monoclonal antibody 1C34-5 raised against human peripheral mononuclear cells was produced. This antibody, a monoclonal IgG1. showed positive reaction with about 90% of T and B lymphocytes, monocytes. granulocytes and bone marrow cells, but negative reaction with red blood cells and platelets by indirect immunoflurorescent technique. 1C34-5 also reacted with leucocytic cell lines except a non-T non-B lymphoid line Reh but not with erythroid line K562, HeLa cells and fibroblast cells so far tested.This antibody was also assayed histologically by an indirect immunoperoxidase technique against a variety of human normal tissue frozen sections. It was found that 1C34-5 bound to all lymphoid tissues including lymph nodes, tonsil, thymus. Peyer's patches and leucocytes scattered in other tissues, but not to all non-hematopoietic tissues as well as erythropoietic foci in fetal liver. Thus. 1C34-5 appears to recognize a human leucocyte antigen specifically.

China ; Dust ; analysis ; Female ; Humans ; Male ; Manufactured Materials ; Occupational Exposure ; prevention & control ; statistics & numerical data ; Occupational Health

Objective To investigate the changes of airway resistance before and after Bronchial Diulation Test in patients with senile asthma and the effect of age on the degree of airway resistance. Methods A total of 29 (> 60 years)senile asthma patients and 21 younger(< 60 y)patients were enrolled in the study. The status of their pulmonary function was determined by MEFV(Maximum expiratory flow?volume curve)and an IOS(impulse oscillometry) system before and after Bronchial Diulation Test,The spirometric indexes such as forced vital capacity,total respiratory impedance,respiratory resistance and respiratory system reactance were collected and analyzed. Results Significant decreases of indexs were found after Bronchial Diulation Test compared with those before Bronchial Diulation Test in the study group(P<0.05,respectively). No significant difference in improvement of indexs was found between the group of patients with senile asthma(age > 60 years)and the group of healthy control(age < 60 years ). Each index of the airway resistance has a very good correlation with FEV1%,with the highest degree of relation is X5%. Conclusion The airway resistance of senile asthmatic patients was significantly improved after diuslation test and these indexes IOS would be valuable in evaluating the changes of airway resistance of senile asthma.

The authors described the procedures for the establishment of clone 515 of the cell strain of osteochondrosarcoma by capillary method.A single cell was sucked into a capillary tube by a microsyringe under the control of a micromanipulator.A segment of the capillary tube with the cell was then planted into the plasma clot in a Carrel flask. After the addition of conditioned medium,the flask was incubated at 37℃.Daily ob- servations were made.The propagation of the single cell,the migration of its progenies out of the capillary tube and the change in form and size of the cells were recorded. 63 days after the isolation,the progenies covered the whole bottom of the flask.First subculture was then made and the clone was established therefrom.

Objective To investigate the predictive value of combined analysis on single nucleotide polymorphisms (SNPs) of X-ray cross-complementing1 ( XRCC1 ) gene 194 and 399 codon,xeroderma pigmentosum group D (XPD) gene 312 codon and glutathione S-transferase P1 (GSTP1) gene 105 codon in platinum based chemotherapy.Methods Direct sequencing was performed to detect XRCC1,XPD and GSTP1 genotypes in peripheral blood from 50 cancer patients receiving platinum-based chemotherapy.Genetic polymorphisms of these genes related to sensitivity of platinum were reviewed.Results Favorable genotypes were Arg/Trp and Trp/Trp in XRCC1 194 codon,Arg/Arg in XRCC1 399 codon,Asn/Asn in XPD 312 codon and Val/Val in GSTP1 105 codon.The response rate to chemotherapy was 57.1％,75.0％,60.9％,85.7％ and 87.5％,respectively.The response rate for patients possessing ≥2 favorable genotypes and those possessing 1 or 0 favorable genotype was 78.9％,36.4％ and 0,respectively.Patients possessing ≥2 favorable genotypes demonstrated higher sensitivity to platinum based chemotherapy,compared with those possessing 1 or 0 favorable genotype ( x2 =25.79,P ＜ 0.01 ).Conclusions Combination analysis of genomic polymorphisms of XRCC1,XPD and GSTP1 may be useful in predicting sensitivity of platinum based chemotherapy.

In a fusion of BABL/C murine spleen cells immunizated with human fetal thymocytes and P_3X_(3)Ag_(,3), myeloma cells, six monoclonal antibodies(McAb) were produced. They were termed HIT_1. HIT_2. HIT_3. HIT_4.HIT_(6-1) and HIT_(6-2), respectively. The specificity of these McAbs were analysed by indirect immunofluorescence technique and FACS.Results showed that they reacted with 80～90%thymocytes,but hardly with peripheral blood mononuclear cells and spleen cells in adults,and nonreactive with red blood cells, granulocytes and platelets, According to their reaction with the tonsil cells, we can divide these six McAbs into three groups: Groupl including HIT_1, HIT_2, and HIT_(?) McAbs reacted approximately with 1/3 tonsil cells; basically GroupⅡ including HIT_(6-1) and HIT_(6-2) McAbs gave negative reaction with tonsil cells; GroupⅢ McAb HIT_4 reacted with 15% tonsil cells, which suggested these were a heterogeneous group McAbs with different specificities. In comparision with OKT series of McAbs in thymus, peripheral blood and tonsil, HIT_(1-3) are similar to OKT_(10) and,HTT6-l and HIT_(6-2) are just like OKT_6,but HIT_4 seems to be a new McAb different frOm HIT_(1-3) and HIT_(6-1) HII_(6-2). The competitive binding assay showed that HIT_(6-1) and HIT_(6-2) labeled with FITC can be inhibited by unlabeled HIT_(6-1) and HIT_(6-2) each other and can also be blocked by OKT_6, suggesting further these antibodies recognized a same epitope on thymocytes. Cross reaction were also demonstrated on HIT_1, and HIT_2 but not on HIT_3, suggesting HIT_1 and HIT_2 recognized the same determinant and HIT_3 recognized another. So six antibodies are McAbs against T cell differentiation antigens.They are useful for research the differentiation of T cells and the classification of malignant lymphadenosis diseases.

Objective To determine the power-time-ablation scope correlogram of a water-cooled single needle electrode radiofrequency (RF) ablation system and to establish a theoretical basis for its practical application.Methods RF ablations were performed using a water-cooled single needle electrode radiofrequency ablation system developed by the authors using fresh ox liver as well as liver and muscles of healthy adult New Zealand white rabbits.The temperature of the ablation area was monitored using a multichannel thermometric system.The maximum ablation scope was determined by detecting the rim at which the temperature was no less than 50 °C.The specific absorption rate (SAR) of the isolated liver tissue was calculated.Results In the treatment voltage range of 100-130V,the process was smooth and steady.No impedance variation was obvious.The maximum diameter of a single ablation was 51 cm.With the treatment voltage at 140-170 V,a larger ablation area could be reached in less time,but eventually the impedance began to increase while the ablation area was no longer expanded.When the treatment voltage reached the range of 180-200 V the impedance almost always increased rapidly out of limits,and the treatment system stopped automatically.The measured SAR value was consistent with the theoretical value.Pathology confirmed that both liver tissue and muscle tissue manifested typical coagulative necrosis.Conclusions The power amplifier,cooling,thermometric and control sections of the RF ablation system worked stably,and the practical ablation effect met the design and clinical treatment requirements.

Objective To explore the appropriate treatment according to the grading system of adolescent idiopathic cervical kyphosis.Methods A retrospective study was performed in 115 adolescent patients with idiopathic cervical kyphosis.The patients were divided into 4 groups according to the magnitude of kyphosis.The initial Cobb angle of 4 groups were 12.7°±1.4° 25.4°±4.8°,47.2°±4.4° and 62.6°±5.7° respectively.The patients in group I were treated with the collar support for 4-8 weeks.The patients in group Ⅱ were treated with skull traction (3-5 kg) and then fixed by cranio-cervical-thoracic plaster.According to the angles between the tangents of posterior vertebral body at each level on lateral cervical radiograph in extension,the anterior fusion levels of the group Ⅲ and angles and range of osteotomy in the group Ⅳ were decided.In group Ⅳ,the patients were treated by two steps.The anterior release and posterior osteotomy were performed firstly.Then skull traction (1/10 body weight) was maintained in order to correct the deformity for 7-10 days,fusion and anterior fusion with autologous bone graft and internal fixation was completed.Results Post-operative radiograph showed that Cobb angle were -5.5°±2.0°,-8.2°±6.1°,-4.5°±6.6° and -2.9°±7.9° in Ⅰ-Ⅳ group after treatment.The deformed appearance of the patients improved significantly.A improvement neck pain and neurologic function were found in all patients.Post-operative MRI showed that physiological curve of the cervical spine was restored,and the cerebrospinal fluid line was clear in the previous kyphosis area.Conclusion Adolescent idiopathic cervical kyphosis has specific characteristics.Surgical strategy is determined by the severity of deformity.

BACKGROUND: The study of cell transplantation to repair injured cardiac muscle and improve cardiac function of dilated cardiomyopathy (DCM) has become a hotspot in recent years. However, the effect of cardiac electrophysiology following transplantation is still unknown.OBJECTIVE: To explore the influence of ailogenic implanted mesenchymal stem cells (MSCs) on cardiac function, structure and electrophysiology of rabbits with DCM.DESIGN, TIME AND SETTING: Randomized controlled animal trial was performed at Electrophysiology Laboratory of Institute of Pediatrics, Chongqing Medical University between January 2004 and May 2006.MATERIALS: Forty-three New Zealand whiterabbits, weighing 3.0-3.5 kg, irrespective of gender, were selected. Adriamycin was produced by Haizheng Medical Products Company of Zhejiang Province, China, No. 050307. The Ultrasonograph SSD-5000 came from Aloka, Japan, and RM6240 multiplying channel electrophysiolograph of Chengdu Instrument Company was applied.METHODS: All animals were randomized into normal group (n=12), cell transplantation group (n=13), and DCM model group (n=13). Except the normal group, adriamycin was applied to create rabbit DCM model, I mg/kg, twice a week for successive 8 weeks. Bone marrow solution was harvested from the remaining 5 rabbits, and MSCs were isolated, amplified and purified using attachment method. Three weeks after modeling, the MSCs were transplanted into left ventricle anterior wall at four sites in cell transplantation group, model group was injected with matching DMEM/FI2 medium, while the normal group was not given any treatment.MAIN OUTCOME MEASURES: At four weeks postoperatively, left ventricular end-diastolic dimension, end systolic dimension,left ventricular ejection fraction, and shortening fraction were monitored by ultrasonograph; the value for monophasic action potential amplitude (MAPA) and the maximum velocity in 0 phase (V,,~), the value for 50% monophasic action potential durations (MAPDs0) and 90% monophasic action potential durations (MAPDg0) were detected by electrophysiolograph. In addition, the cardiac tissues harvested from implanted region were observed by light microscope and electron microscope, and also the expression of cardiac troponin T (cTnT) and connexin 43 (Cx43) was detected through immunohistochemistry.RESULTS: Of 43 rabbits, 9 rabbits each of the transplantation group died of the acute or chronic toxic effects of Adriamycin, finally, 25 rabbits were included in final analysis. Compared with model group, the end systolic dimension was diminished, and the left ventricular ejection fraction and shortening fraction in cell transplantation group were significantly increased (P ＜ 0.05). The MAPDs0 and MAPDgo in cell transplantation group prolonged significantly compared with model group (P ＜ 0.05). In model group,cardiac myocytes appeared mitochondria swelling and hyperplasia, and their sarcomere had different lengths, arranged unevenly,accompanied by abnormal contraction bands. In addition, myolysis was found in parts of myocardium under electron microscope.However, the structural abnormalities in the cell implantation group were less than the DCM model group, and the implanted MSCs could express cTnT and Cx43.CONCLUSION: Allogenic MSCs transplantation can improve cardiac function, lessen structural abnormalities and may inhibit the progression of electrophysiology derangement.