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Biomedical subjects

J X Guo

Publications and source records attributed to J X Guo.

36 records · Page 2Linked to original sources
PubMed1993

Experimental studies of laser myocardial revascularization in rats.

Myocardial revascularization by Nd: YAG laser used in rats with myocardial infarction was studied. The left coronary artery was ligated and the laser channels with a diameter of 300 microns were made immediately by 2.5-4.2 W lasersonics YAG unit. After 24 hours, the rats were killed. Evaluation included hemodynamics, lactate dehydrogenase of myocardium and myocardial infarct size. The results showed that laser myocardial revascularization reduced myocardial infarct size and enzyme leakage, and improved left ventricular function. The study may provide theoretical basis for the clinical applications of this new technique in the treatment of ischemic heart disease.

Animals↗
PubMed1992

[Arteriography and bronchial artery embolization for massive hemoptysis in 100 cases of tuberculous].

Bronchial arteriography and embolization with sponge gelatin were performed in 100 tuberculous patients of massive hemoptysis. Three direct signs and other six indirect ones were found in arteriographies, Those signs were roentgenographic abnormalities for defining bleeding sites. 100 massive hemoptysis cases were treated with sponge gelatin embolization in bronchial artery. The results are satisfactory, the success rate were 92.9%, 87.4% and 79.0% at one week, one month and three months respectively. The advantages of arterial embolization and the reasons of failures were discussed in this paper.

Bronchial Arteries↗
PubMed1992

[Morphological and histological studies on the Chinese drug shan-dou-gen].

The Chinese drug "Shan-Dou-Gen" has been used for removing toxic heat, promoting the subsidence of swelling and soothing the sore throat since the ancient time. The authors made a survey of the drug "Shan-Dou-Gen" available in drug markets as well as the plant origin from the drug producing districts. The results showed that the drug "Shan-Dou-Gen" used in different regions in China at present are the roots or rhizomes derived from 9 species: Sophora tonkinensis Gagnep. (Leguminosae), Menispermum dauricum DC. (Menispermaceae), Indigofera amblyantha Craib (Leguminosae), I. carlesii Carib, I., fortunei Craib, I. decoa Lindl. var. ichangensis Y. Y. Fang et C. Z. Zheng, I. kirilowii Maxim. et Palibin, I. potaninii Craib, and Beesia calthaefolia (Maxim.) Ulbr. (Ranuculaceae). In this paper, the morphological characters of the crude drugs are described, compared and illustrated with photographs. The histological structures of the used parts are described, compared and illustrated with line drawings. The morphological and histological similarities and differences found among the above 9 species are summarized, and the key for the identification of the crude drugs is provided. As the drug "Shan-Dou-Gen" derived from different species has different actions and dosages, it is necessary to give different names to different species and use them correctly.

Medicine, Chinese Traditional↗
PubMed1989

Effects of pulse excimer laser irradiation on the human left ventricular wall.

This study was to assess the potential application of excimer lasers in the ablation of myocardium in vitro for the treatment of constant ventricular tachycardia or hypertrophic cardiomyopathy. A fresh human heart and EMG model 103 XeCl pulse excimer laser machine were used. The pulse repetition rate varied from 1 to 7 Hz. Irradiation directly on the left endocardial and epicardial walls lasted for 10 seconds and was repeated 3 times, creating 3 craters. The histological changes were examined by light microscope. Results showed very close relations between the depth or volume of vaporized craters and the pulse repetition rate on the endocardial (r = 0.9674, P less than 0.001 and r = 0.8962, P less than 0.01, respectively) and epicardial walls (r = 0.9602, P less than 0.001 and r = 0.9612, P less than 0.001, respectively). A sharp, clear border without debris or coagulating necrosis was seen under the microscope. We concluded that the pulse excimer laser, differing from Ar+ or Nd:YAG lasers, might be a powerful tool for manipulating the human ventricular wall, but more work needs to be done before it can be widely applied in the treatment of cardiovascular disease.

Chlorides↗
PubMed1989

[Percutaneous coronary laser angioplasty in a patient with chronic total obstruction of the right coronary artery].

Percutaneous coronary laser angioplasty was performed in one patient with total occlusion of right coronary artery without further balloon angioplasty in the ablated site. First of all, we used intracoronary urokinase in a total amount of 60,000 units that resulted in opening the total occluded right coronary artery to provide a passage of guidewire of laser catheter. Then a laser catheter was inserted through the guide catheter and its metal cap was in contact with the atherosclerotic lesion. The Nd:YAG laser was activated to vaporize the lesion (total energies of 54 J). Finally, the degree of residual stenosis was reduced from 95% to 20%. Percutaneous coronary laser angioplasty is a new method in treating coronary artery disease, yet it is still in its infant stage and further work is needed to develop this technological procedure.

Adult↗
PubMed1989

Clinical application of coronary laser angioplasty during coronary bypass surgery.

Laser irradiation offers the potential of removing atherosclerotic plaques from blood vessels. We used the Nd:YAG laser to treat coronary atherosclerotic obstruction in patients undergoing coronary bypass. Of the 7 patients treated, all were successfully recanalized without damage to the artery wall (a mild hematoma developed in 1 case), and follow-up examination showed patency 4 months after operation. We conclude that Nd:YAG laser shows promise for the treatment of atherosclerotic obstructions, but more study is needed before wide clinical application is justified.

Adult↗
PubMed1986

Rearrangement of tubulin, actin, and myosin in cultured ventricular cardiomyocytes of the adult rat.

Antitubulin, phalloidin, and antimyosin were used to study the distribution of microtubules, microfilaments, and myofibrils in cultured adult cardiomyocytes. These cells undergo a stereotypic sequence of morphological change in which myotypic features are lost and then reconstructed during a period of polymorphic growth. Microtubules, though rearranged during these events in culture, are always present in an organized network. Myosin and actin structures, on the other hand, initially degenerate. This initial degeneration is reversed when a cell attaches to the culture substratum. Upon attachment, new microtubules are laid down as a cortical network adjacent to the sarcolemma and, subsequently, as a network in the basal part of the cell. Actin and then myosin filament bundles appear next, in a pattern corresponding to the pattern of the microtubules. Finally, striated myofibrils are formed, first in the central part of the cell, and subsequently in the outgrowing processes of the cell. A mechanism is suggested by which the eventual polymorphic shape of a cell is related to the shape of its initial area of contact with the culture substratum. Finally, a model of myofibrillogenesis is proposed in which microtubules participate in the insertion of myosin among previously formed actin filament bundles to produce myofibrils.

Actins↗