Showing papers by "Chinese PLA General Hospital published in 1998"

Sonographically guided microwave coagulation treatment of liver cancer: an experimental and clinical study.

Abstract: Percutaneous microwave coagulation was performed with a modified system in animal experiments and in a clinical study to evaluate this technique as a treatment option for liver cancer.As an in vitro study, a microwave electrode was inserted 5-6 cm into separated egg white, homogenate of pig liver, and pig liver, with different power outputs and different lengths of inner conductors. In the animal experiment, the sonographically guided coagulation was performed percutaneously nine times and at laparotomy 43 times on 17 adult dogs. The thermal needles were placed parallel to and 5 mm, 8-12 mm, and 15 mm from the electrode. Clinically, 41 patients with hepatocellular carcinoma and 10 patients with hepatic metastases were treated with a 60-W microwave emission for 240-300 sec.Microwave coagulation using the modified system at 60 W for 300 sec produced a necrosis volume of 3.7 x 2.6 x 2.6 cm. The coagulated volume was elliptic when the exposed inner conductor of the electrode was 27 mm. The temperature at the ...

Changes of skin perfusion after photodynamic therapy for port wine stain.

Abstract: OBJECTIVE To obtain an objective assessment of the curative effectiveness of photodynamic therapy (PDT) for port wine stain (PWS), we investigate the relationship between the microvascular perfusion changes of PWS and the blanching of the lesions before and after PDT. METHODS Twenty-four patients (18 females and 6 males with a total of 28 lesions) suffering from PWS were treated with PDT. The lesions of various extents were located on the face and neck. After intravenous injection of photosensitizer hepatoporphyrin derivative (HpD), the copper vapor laser was adopted as light source and the lesions of PWS were irradiated. The laser Doppler perfusion imager (LDI) was used to measure the microcirculatory perfusion of PWS before and after PDT and comparison with the normal skin was done. RESULTS All the lesions showed remarkable decrease of tissue perfusion after PDT. It was shown that the mean, maximal and minimal values of tissue perfusion in the pre-treatment group were significantly higher than those in control group (P < 0.01). Six months after PDT, the mean, maximal and minimal values of perfusion with the lesions were reduced, with significant difference from pre-treatment group (P < 0.01), but no significant difference from control's. The colors of lesions were correlated with decrease of microcirculatory perfusion, which became lightened close to normal skin color without causing any scarring. CONCLUSIONS PDT is one of the most effective modalities for PWS. The microcirculation perfusion can reflect the degrees of PWS objectively. The curative effectiveness of PDT for PWS is due to tissue microcirculation response.

Stapled anastomosis in esophageal resections with Chinese staplers: a retrospective study of 1965 consecutive cases.

Abstract: OBJECTIVES To investigate the safety and efficacy of mechanical anastomosis with Chinese staplers in the surgical treatment of esophageal carcinoma and carcinoma of gastric cardia in order to find out an alternative effective anastomotic technique to hand-sewn method. METHODS From August 1980 to April 1996, there were totally 1264 cases of esophageal carcinoma and 701 cases of carcinoma of gastric cardia receiving esophagogastric anastomosis with Chinese staplers combined with telescope suturing of seromuscular layers after resection of tumors, with age ranging from 28 years to 81 years and a man to woman ratio of 4:1 (1572/393). The anastomosis was performed at the cervical region in 44 patients, and intrathoracically in 1921. Our technical essential points also included fixation of the gastric substitute to the thoracic apex or mediastinum with 3-4 stitches to relieve the anastomotic tension. RESULTS Compared with the reported postoperative leakage rate from 2%-4% in China and 4.2%-12.3% abroad, our techniques reduced the total leakage rate to 0.8%, that is, cervical leakage rate was 11.4% (5/44), and intrathoracic leakage rate 0.57% (11/1921). The intrathoracic leakage rate was 0.99% (8/808) for the first 8 years, and 0.27% for the following 8 years. There was no leakage (0/350) in the last 3 years. There anastomotic stricture occurred in 98 patients (4.99%) which could be relieved by Bougie or balloon dilatation. The total operative mortality was reduced to 0.76%. CONCLUSIONS Mechanical anastomosis with Chinese staplers combined with telescope suturing should be an effective method to prevent the occurrence of anastomotic leakage after esophageal resections.

The clinicopathological and immunophenotypical features of 162 cases of gastrointestinal stromal tumor

Abstract: OBJECTIVE To demonstrate the clinicopathological and immunophenotypical features of gastrointestinal stromal tumor (GIST). METHODS One hundred and sixty-two cases of GIST were retrospectively studied. Among them, forty-six cases were immunostained using antibodies against vimentin, CD34, muscle specific actin (MSA), smooth muscle actin (SMA), neuron specific enolase(NSE), S-100 protein, synaptophysin (SYN), cytokeratin(CK), CEA, LCA. RESULTS Clinically, male patients predominated with a male to female ratio of 3.8:1. The average age was 50 (range 6-74). The most common symptoms were gastrointestinal bleeding and abdominal mass in 45% and 39% of the cases, respectively. The common anatomical locations were stomach (43%), ileum (20%), jejunum (18%). Pathologically, all the tumor arose from the muscular layer. The tumor diameter varied from 0.5 to 43 cm. In 55% of the cases, the tumor was malignant. The main component cell types were spindle and epithelioid in appearance. Immunophenotypically, percentage of positivity for the 10 antibodies was as follows: vimentin, 100% (39/39), CD34, 64% (23/36), MSA, 47% (16/34), SMA, 41% (14/34), NSE, 61% (17/28), S-100 protein, 19% (4/21), SYN, 15% (3/20), CK, CEA, and LCA were negative. CONCLUSION GIST is the most common mesenchymal tumor of the gastrointestinal tract. Immunostaining confirms that only some of the GIST shows partial differentiation toward smooth muscle, neuron, or both.

Photodynamic therapy for port wine stains

Abstract: Previous therapies for port wine stains usually cause unacceptable scarring or obtain poor effect. Because port wine is a congenital vasculopathy consisting of an abnormal network of capillaries in the upper dermis with an overlying normal epidermis and the researchers found the tumor blood vessels were occluded accompanying the necrosis of the tumor after PDT. The author and his colleagues started a series of animal and clinical studies since 1991 about photodynamic therapy for port wine stain an they established the method of PDT for PWS. The clinical studies of over 1500 cases proved that PWS can be cured by PDT without scar formation because there is no thermal effect involved. No relapse was found within a maximum follow-up of six years.

Stress distribution in the mandible with unilateral condylar fracture.

Abstract: OBJECTIVE The purpose of this study was to investigate the influence of unilateral condylar neck fracture upon the stress distribution in the mandible and the temporomandibular joint (TMJ) to realize primarily the biomechanical mechanism of the temporomandibular joint disorders (TMD) caused by TMJ injury. METHODS The character of stress distribution in the mandible of a normal human and a patient with TMD induced by unilateral condylar neck fracture followed by malpositioned healing was analyzed quantitatively and compared during centric occlusion by combining spiral computed tomography scanning technology with the three-dimensional finite element method. RESULTS The patient with unilateral condylar neck fracture followed by malpositioned healing had unbalanced stress distribution in the mandible, such as differing nature and value of stress. The stress in the fractured side was higher than in the nonfractured side, in which the condyle was more evident. The maximum principal stress and minimum principal stress of each region in the fractured mandible were much higher than those in a normal mandible. Stress quality also differed. CONCLUSIONS The abnormal stress changes after unilateral condylar neck fracture with malpositioned healing may be related to the effect of condylar shape change on masticatory muscle function and occlusion. TMJ injury not only damaged the condylar structure, but also compromised its biomechanic environment. It is preliminarily thought that unbalanced stress distribution, evidently increased stress, and varied stress character are biomechanic mechanisms of TMD. Condylar dislocated fracture should be treated promptly and properly to maintain the proper prognostic stress distribution.

Study on the metastatic mechanisms of human giant-cell lung carcinoma comparison between the strains C and D.

Abstract: The biologic characteristics of the two human giant-cell lung carcinoma strains with high (strain D) and low metastatic potential (strain C) were studied, including karyotype of chromosome, intracellular free calcium ([Ca2+]i), morphologic changes of cell surface and the expression of nm23-H1, p53, ras, c-myc, c-erbB2, bcl-2 genes and PCNA. The correlation between different biologic features and the metastatic potential of the two strains was analyzed. We found: 1) Both strains had the karyotypic abnormality of -13, -14, -15, +20, +21 with seven same marker chromosomes. Only strain D had the karyotypic abnormality of +7, -17, -18, +X, 7p+; 2) [Ca2+]i of the strain C (984.7 +/- 573.8) and D (517.6 +/- 216.6) was significantly different (p < 0.05). The amplitude of intracellular calcium oscillations of strain C was lower than the one of strain D; 3) strain C had more villous-like protrusions on the cell surface, whereas strain D had more bubble-like protrusions; 4) The expression of nm23-H1 and p53 protein of strain C was all higher than that of strain D. The expression of PCNA of strain C was lower than strain D; 5) nm23-H1 mRNA levels of strain C was lower than that of strain D. We consider that the karyotype of chromosomes, intracellular free calcium, the structure of cell membrane and the expression of nm23-H1 gene, p53 gene, PCNA could be closely related to the metastatic potential of human giant-cell lung carcinoma. They could be used as the sign for judging whether the tumor will metastasize in clinical practice as well as in judging the prognoses of patients.

Direct effects of laser irradiation on cells in photodynamic therapy

Abstract: Liu TCY et a! (SPIE 2887, pp. 140-15 1, 1996) have put forward the biological information model on low intensity laser irradiation (BIML). Low intensity laser irradiation couples with intracellular messenger through the chromophore absorption in the cell membrane: hot-color (red, orange, yellow) laser irradiation activates cAMP phosphodiesterase through G, protein or activates phosphoinositide phospholipase C (PLC) through Gq protein, or activates one of receptor-associated kinases: cAMPL; cold-color (green, blue, violet) laser irradiation activates adenylate cyclase through G, protein: cAMP'l'. In this paper, we applied BIML to studying the direct effects of laser irradiation on cells in photodynamic therapy. It was concluded that cold color laser irradiation PDT is better than hot color laser irradiation PDT from the viewpoint of the effects on cells and the short term effects on cancer, but hot color laser irradiation PDT is superior to cold color laser irradiation PDT with respect to the long term effects on cancer. Key Words: photodynamic therapy; cancer; transmemberane signal transduction

Microbiological turbidimetric method in determination of serum concentrations of ciprofloxaxin

Abstract: Aim The application of microbiological turbidimetric method to determination of serum concentrations (C) of ciprofloxacin (CPLX) was studied.Methods A series diluted concentrations of CPLX were prepared with blank serum. The solution was put in a research unit with standard bacteria (ATCC 27853) dilution of 107 cfu/ml and incubated in Avantage analysis system. Absorbance (A) was recorded once every 5 min in a wavelength of 670 nm.Results There was a liner relationship (r=0.9950,n=8) between concentrations of CPLX and absorbance. The regression equation was C=9.4020-22.55 A. The lowest detectable concentration was 0.03 μg/ml. The rate of recovery of the method was 96.5%～108.0%. The coefficient of variation within a day was 2.11%～9.13% while the coefficient of variation in different days was 1.99%～9.72%. Conclusion The microbiological turbidimetry is a rapid, convenient and accurate method to determine the concentration of CPLX.

Effects of gentamicin on survival and neuritogenesis of cultured mouse spiral ganglion cells

Abstract: The effect of gentamicin on survival and neuritogenesis of cultured spiral ganglion cell(SGC) from NIH mouse 1-5 days after birth was observed. Different doses (25, 50 and 100 mg/L) of gentamicin were add to the medium of SGC, and cultured for 14 days. After that, the specimen was fixed with 4% paraformaldehyde and stained with toluidine blue. The amount of survival SGC was counted, and the length of neurite was measured with micrometer under microscope. It was shown that the survival and length of neurite of SGC had no difference between Gentamicin treated groups and control groups, and there were also no difference among 3 gentamicin treated groups. It was suggested that gentamicin had no effect on survival and neuritogenesis of SGC. The effects of aminoglycoside antibiotics on SGC were probably secondary to the injury of Corti's Organ.