[Relationship between airway obstruction and inspiratory muscle function]

Measurement of Pimax (maximal static inspiratory mouth pressure), Pi (static inspiratory mouth pressure) and 5 routine pulmonary function tests, which inspect the degree of airway obstruction, was done in 157 patients with COPD and 55 normal subjects. The results indicated that along with the deterioration of COPD, the Pimax was getting decreased and the Pi/Pimax was getting increased. In the mild and moderate COPD groups, however, the Pi and Pi/Pimax showed no statistical significance, which was the only exception. Our results suggested that (1) the airway obstruction could reduce the inspiratory muscle strength; and (2) the Pi/Pimax might be useful in clinical practice for early diagnosis of inspiratory muscle insufficiency.

Serologic survey of giant pandas (Ailuropoda melanoleuca), and domestic dogs and cats in the Wolong Reserve, China

Sera from captive and recently rescued giant pandas (Ailuropoda melanoleuca) in the Wolong Reserve, China, were examined by serum neutralization or hemagglutination inhibition for antibodies to canine distemper virus (CDV), canine coronavirus (CCV), canine herpesvirus (CHV), pseudorabies virus (PRV), canine adenovirus type 2 (CAV), and canine parvovirus (CPV). Serum samples from village domestic dogs and cats, which run free throughout the reserve also were examined. Antibodies against CPV were detected in six of eight giant pandas and all dogs and cats tested. The origin of the virus was not determined. Two of eight giant pandas and two of seven dogs had CDV antibody titers. Three of eight pandas and three of seven dogs had CCV antibody titers. Four of eight pandas and two of seven dogs had CAV titers; the titers in dogs were very high. No pandas or dogs had evidence of exposure to CHV or PRV.

[Specific curative effects of nitrosourea drugs on tumor cells with Mer--phenotype in Chinese]

O6-Methylguanine DNA methyltransferase (O6-MT) activity and cellular sensitivity to nitrosourea drugs of 10 kinds of tumor cell strains derived from Chinese patients were measured by 3H radioactivity and colony-forming ability, respectively. The results in vitro showed that nimustine (Nim) 25 micrograms.ml-1 and carmustine (Car) 20 micrograms.ml-1 exhibited specific killing effects on Mer-phenotype tumor cells characterized by low O6-MT activity. In vivo both Nim and Car (25 mg.kg-1.wk-1 x 4 wk, ip) had specific curative ability to Mer- tumor cells implanted in nude mice. These findings suggested that assay of O6- MT activity in tumor biopsy could be used as a predictable guide to human tumor chemotherapy with nitrosourea compounds.

[Effects of "he xiang zhuang gongfu" on respiratory function in healthy adults]

Eleven healthy adults who practised He Xiang Zhuang Gongfu (HGF) were followed for 6 months; 15 pulmonary function tests were determined before HGF practice, 2 months and 6 months after HGF practice. All 11 subjects took the HGF exercise every day for 30 minutes. Samplings were taken before subjects had ever practised HGF as control value, immediately and 30 minutes after HGF exercise. In the 2nd month and 6th month of HGF practice. The results indicated that VO2 decreased after 2 and 6 months HGF practice, and the effect even persisted to 30 minutes after HGF exercise, indicating that HGF may reduce metabolic rate and decrease the oxygen consumption of body. The possible mechanism was discussed. MVV had an up tendency after HGF practice, which suggested the possibility of strengthening respiratory muscle by HGF. HGF may be a good physical exercise and can induce a wakeful hypometabolic physiologic state.

CT-based simulation with laser patient marking

A CT-based simulator has been assembled based on a commercial CT scanner, virtual simulation software developed at the University of North Carolina and a laser drawing device to transfer the radiation portals from the virtual simulator to the patient. The simulation process can be completed in approximately 1 h; under most cases, the treatment portals can be designed and the patient marked in one session. The device has an inherent accuracy of +/- 1 mm. The portal projection accuracy in clinical cases is observed to be better than 2 mm.

Correction for distortion in a beam outline transfer device in radiotherapy CT-based simulation

In using a CT scanner as a radiation therapy simulator, it would be helpful to be able to transfer the beam outline from the computer plan to the patient's skin. A beam outline transfer device has been constructed and installed on a Siemens' DRH CT scanner gantry. The planned treatment beam geometry from a 3-D computerized simulation and planning system can be projected onto the patient's skin surface accurately and efficiently. The positioning accuracy achieved is within +/- 0.1 cm over a 20 cm x 20 cm field. Integrating the device into the CT scanner, simplifies the device and reduces the cost over an externally mounted device. Two unsuccessful methods to correct the projection distortions are also mentioned. In order to achieve the reported beam outline transfer accuracy, a system based on our empirically derived calibration procedure is described.

[Pulmonary function disturbances in patients with hepatic cirrhosis]

The results of five pulmonary function tests on 52 patients with uncompensated hepatic cirrhosis were presented. Compared with matched healthy adults, the patients had decreased values of VC, TLC and DLCO, and their RV/TLC increased (P < 0.05-0.001). Possible pathogenic factors were investigated. The ascites showed evident influences on pulmonary function. In addition to the disorders detected by the above 4 tests, FRC decreased in the patients with ascites. A comparison between the patients with albumin below 30g/L and the patients with albumin above 30g/L revealed that reduced plasma albumin also played role in decreasing VC, TLC and DLCO. Besides the effects of ascites, severe varices of esophagus should have relation to the increase of RV/TLC and the decrease of DLCO.

[Application of DNA interstrand cross-link assay to estimate the sensitivity of tumor cells to alkylating agents]

Fluorometric method was modified and used to detect DNA interstrand crosslinks (ISC) in tumor cells after treatment with cisplatin. Linear dose-response curve was obtained. The difference of DNA ISC formation between HeLa S3 (containing O6-methylguanine methyltransferase, Mer+) and HeLa MR (devoid of O6-methyguanine methyltransferase, Mer-) cells was studied after treatment with alkylating agent 1-(4-amino-2-methyl-5-pyrimidinyl)methyl-3-(2-chloroethyl)-3-nitrosourea hydrochloride (ACNU). The survival fraction was also observed in Mer+ and Mer- cells treated with ACNU. It seems that DNA ISC formation may be used as one of the possible criteria in estimating the sensitivity of tumor cells to bifunctional alkylating agent and forecasting the efficacy of tumor chemotherapy.

[Argon replacing helium in measurement of pulmonary carbon monoxide diffusing capacity, its normal value and clinical application]

Measuring DL COSB of 120 normal subjects by using a gas mixture, in which helium was replaced by argon, we determined the DL COSB mean value, standard deviation and the predicted value formula for both sexes. The lower limit value of DL COSB for normal subjects was defined and the positive diagnostic value investigated. A ratio of actual value to predicted value below 80% was defined as abnormal. With this diagnostic criterion 43 cases of silicosis and diffuse pulmonary interstitial fibrosis were investigated, the positive rate of the cases being 90.70%, with a false positive rate of below 10% for normal subjects, which indicates that this gas mixture and the criterion are applicable for clinical practice.