1995年 · 第108卷第01期

Genomic DNA was extracted from peripheral blood lymphocytes of 105 healthy and 75 NIDDM Chinese subjects. The fragment located in exon 13 of the low density lipoprotein receptor (LDLR) gene was amplified by polymerase chain reaction (PCR), and digested with restriction enzyme HincII. LDL, TC and TG levels were measured in all subjects. Investigations were conducted to explore the correlation between the HincII RFLP of LDLR gene and NIDDM in the Chinese population. The results showed that no significant correlation existed between this RFLP locus and NIDDM. Marked differences were found, however, between the genotype distribution of low LDL level subgroups of NIDDM patients and normal controls. It was inferred that the H1 allele might be associated with high blood cholesterol levels, and the H2 allele with low cholesterol levels. Disturbances of lipid metabolism occur frequently in diabetes mellitus. This study suggested that differences in LDLR genotypes may affect the phenotypes of lipid metabolism.

Ten outbred pigs were each operated on for three times. First, a 130 cm length of terminal ileum of each pig was isolated on its vascular pedicle as a Thirty-Vella loop. One week later, the solitary ileal segments were transplanted heterotopically in two pigs. And after 28 days of heterotopic transplantation, the transplanted intestine was interposed into continuity of host intestine as orthotopic transplant. During the experiment, tests were made on 6th day after the first operation (period I), the 14th (II), 28th (III) day after heterotopic transplantation, and 3 weeks after interposition (IV) respectively for the levels of glucose, palmitate and leucine. Additionally, at period I, III, and IV, a 3 cm length of intestinal mucosa was excised for morphologic observation and determination of DNA, RNA and protein contents. After heterotopic transplantation, the absorptive function of transplanted intestine was severely impaired for two weeks. The absorption of glucose and palmitate was partially recovered by period III, at which time leucine level had return to normal. At period IV, the absorptive function of glucose and leucine had surpassed normal levels, while palmitate had risen to the level of pretransplantation. After transplantation, at period III, DNA, RNA and protein contents were well below normal. Three weeks after orthotopic transplantation, RNA and protein had risen to normal level, while DNA content remained below normal. The morphologic changes during the experiment were correlated with the changes of contents in RNA, protein and DNA.(ABSTRACT TRUNCATED AT 250 WORDS)

The structure of cancellous bone of synovial joints was studied under the scanning electron microscope in 4 young cadavers. It was discovered that in all specimens, the cancellous bone beneath the whole coverage of the articular cartilage had a honeycomb pattern in appearance formed by many arched trabeculae running in different directions, and that the major orientation of the arched trabeculae was toward the articular surface. The arms of one arched trabecula extended in different directions, forming the tops of other arched trabeculae; the direction of the collagen fibers conformed circumferentially with that of the arch, but the collagen fibers at the intermediate part of the common arm of the adjacent arched trabeculae crossed in a woven pattern, passing from one trabecula to another. It enables the whole end of the articular bone to have the capacity of integral deformation. That is the foundation of the character of compliance which is essential to the contact of the articular surfaces changing from incongrouity to total congrouity during normal load transmission. This special type of construction is just like the truss structure in the architectural engineering, and therefore the authors suggest to name it the "Truss Structure" of the cancellous bone. The relationship between integral deformation and the following two factors, compliance and incongrouity of the articular surface provides an explanation that the truss structure of the cancellous bone is the morphological basis of high load-bearing capacity and character of compliance of the synovial joint.

Warm ischemia is one of the most important causes of valvular damage from death of donor to its valve harvesting. This study aimed at using qualitative and quantitative methods to characterize warm ischemic injury through models of SD rat's aortic valves and design to show the relationship among ultrastructural, biological and biochemical changes concerning with the length of warm ischemia time (WIT). 102 harvested SD rat's aortic valves were divided into 6 groups of different ischemic time for this study. 432 photomicrographs of transmission electron microscopy (TEM) were put into computer for analysis. The volume ratio of nucleus to plasma in cells (Vnp) and the ratio of extramembrane area to volume of mitochondria (S/V) were used to characterize the degree of valvular cell injuries. Valvular cells culture and biochemical metabolism including glucose degradation and 3H-TdR absorption rate were adopted. The valvular cells depicted a significant decrease and 3H-TdR taking-up also being inhibited under the influence of prolonged WIT.

Hearts of pressure-overload hypertrophy show an increased activation of intracardiac renin-angiotensin system which may contribute to ischemia and reperfusion injury. The purpose of this study is to evaluate whether the hypertrophied myocardium is more vulnerable to ischemia and reperfusion injury and to find out its relation to the cardiac renin-angiotensin system. Hypertrophied rat hearts induced by abdominal aortic banding for 6 weeks were subjected to 2 hours of hypothermic ischemic arrest followed by 30 minutes of reperfusion, and their cardiac function recovery was compared with that of sham-operated normal control hearts. The cardiac renin activity and angiotensin II content before ischemia and after reperfusion were determined. It was found that both the pre-ischemic renin activity and angiotensin II level were higher in hypertrophied myocardium than those in the control: ischemia and reperfusion injury increased both renin activity and angiotensin II content in the two groups, but the renin activity and angiotensin II level were further elevated after reperfusion in the hypertrophied hearts than those in the control hearts. Meanwhile, the cardiac function recovery after 30 minutes reperfusion in the hypertrophied hearts was poorer than that in the control. Correlation analysis revealed that there was a negative correlation between the cardiac output recovery and the myocardial angiotensin II content (r=-0.8411, P<0.001). It is concluded that ischemia and reperfusion injury can activate cardiac renin-angiotensin system in isolated rat heart, which may be responsible for the increased susceptibility of the hypertrophied myocardium to ischemia and reperfusion injury.

The effects of single dose of PGE2 combined with vitamin E and with estradiol on experimental atherosclerosis were studied by means of morphological, ultrastructural, autoradiographic and several functional techniques. The results showed that two combined treatment groups had more coordinative inhibition on aortic and coronary atherosclerotic lesions, as well as on platelet aggregation, smooth muscle cell proliferation and lipid peroxidation than that of single dose of PGE2. It was revealed that the coordinative mechanism might be closely related to the synergistic inhibitory function of above-mentioned drugs on endothelial permeability, platelet aggregation, smooth muscle cell proliferation and lipid peroxidation.

The distribution of six lectin receptors, WGA, RCA-1, LCA, PSA, PNA and SBA in 111 human gliomas, 8 human normal brain tissues and 11 reactive hyperplasia of astrocytes was observed by means of avidin-biotin-peroxidase technique. Their grays were also quantified with the image analysis instrument. The results showed that WGA and RCA-1 might be used as markers for distinguishing well-differentiated astrocytomas from the reactive hyperplasia of astrocytes especially the reactivity of astrocytes had a specific feature with RCA-1. The difference in quantities of WGA, RCA-1, LCA, PSA receptors between astrocytomas, ependymomas and oligodendrogliomas, medulloblastomas might conduce to the diagnosis and classification. For astrocytomas, it was also showed that a quantity of LCA and PSA receptors was correlated with the degree of cell differentiation. Therefore, they can be used as valuable markers of the differentiation of astrocytomas.

Many patients with chronic venous insufficiency syndrome caused by the "relative valvular incompetency" with venous dilatation. Eighty-six per cent of the cases can be cured by reducing the femoral venous diameter by simply using the encircling suture method just distal to the first femoral valvular sinus. Our preliminary results suggest that such a method of surgical treatment is simple and efficient.

Reconstruction of the hypopharynx and upper esophagus after resection of advanced pyriform sinus cancer, is usually complicated and time-consuming. Laryngotracheal flap was used in hypopharyngoesophageal reconstruction for 26 elderly patients with advanced pyriform sinus cancer Pharyngocutaneous fistula developed in 5 patients and healed spontaneously without further surgery. Full diet was resumed in all the patients. The surgical technique and its advantages and disadvantages are discussed. The laryngotracheal flap in the reconstruction of hypopharyngoesophageal defect for elderly patients is a procedure of choice.

The association of gluckinase (GCK) gene with type 2 (non-insulin-dependent) diabetes mellitus was investigated in 168 Chinese subjects (85 unrelated type 2 diabetics and 83 non-diabetic controls). The microsatellite polymorphism marker, GCK-5', was amplified with polymerase chain reaction. Four alleles were observed in Chinese population with length varying from 137bp to 143bp and the most common one being the 139bp allele 3. In comparison with non-diabetics, allele 4 was significantly increased in type 2 diabetes (10% versus 38, respectively; χ 2=6.773, P=0.009); genotype 44 and 4X (X denotes any allele other than allele 4) were significantly increased in type 2 diabetes (16% versus 6% respectively; χ2=6.439, P=0.011). The frequency difference was also shown in overweight/obese subgroup comparison (χ2=7.718, P=0.021), but not in lean/normal-weight subgroup comparison. No differences of age of onset and frequency of positive family history were observed between type 2 diabetic patients with genotype 44 or 4X and those with XX. The risk for type 2 diabetes in Chinese with genotype 44 or 4X was about 3.5 times higher than in Chinese with genotype XX. Therefore, GCK gene was associated with Chinese type 2 diabetes.

Pregnancy induced hypertension (PIH) is a common complication in pregnancy and prenatal stage. Because the direct and indirect relationship between low calcium intake and many diseases, such as rachitis, young age myopia and hypertension, calcium supplementation has been a hot topic among nutritionists. Randomized trials of calcium supplementation during pregnancy were conducted in 212 healthy primipara. They were divided into 4 groups and gave 120mg, 240mg, 1g or 2g of calcium daily from 20 to 28 wks of gestation up to delivery respectively. As a result, the incidence of PIH was 8.9%, 7.5%, 8% and 4% respectively in these groups. The control group (106 pregnant women) who did not receive calcium gave an incidence of 18%. Supplementation of 2g of calcium daily showed significant results in lowering the incidence of PIH (P<0.05) without any adverse effects. In 1992 calcium supplementation was widely used in antenatal-clinic. 200 cases with intake of 2g calcium were compared with corresponding non-calcium supplementation cases, and the incidence of PIH was 7.5% and 16.5% (P<0.005) respectively. Mediating parathyroid hormone and renin activity are thought to be the effect of calcium on decreasing the incidence of PIH.

Multiple organ dysfunction (MOD) after valve replacement was studied in a period of 1980-1991. The incidences of MOD involving 2, 3 and 4 organs were 17.1%, 5.6% and 4.3% with corresponding mortalities of 12%, 18.5% and 76.2%. We focused on dysfunction of more than 3 organs, the dreadful complication, which can be divided clinically into three types: acute (type I), deteriorating (type II), and pulmonary infection (type III). In MOD, the function of heart and lung is primarily depressed after surgery. So the predisposing factors of MOD are acute pump failure and hypoxemia, and the possible triggering factor is infection, especially pulmonary infection, which re-endangers the organs recovering from the primary blows. Thus prevention of pulmonary infection is of same importance as treatment of pump failure and hypoxemia.

The pelvic radiographs of 60 patients with paraplegia or quadriplegia were reviewed and double cortical line in the acetabular roofs on both sides was found in 35 patients. It was concluded that the double cortical line was a radiologic sign of disuse osteoporosis after spinal cord injury. It was noticed that the acetabular double cortical line in incomplete paralysis was not so prominent as that in complete paralysis (P<0.05), suggesting that the degree of acetabular osteoporosis may be related to the severity of spinal cord injuries. The etiology of double cortical line and related factors were discussed.

Superior mesenteric ganglia of six fetuses (35-40 weeks old) were investigated by histochemical fluorescent method. In addition to solitary SIF cells and clusters of SIF cells reported previously, a new structure of SIF cells was found and named "SIF-cell nodule". The SIF-cell nodule was composed of a large number of SIF cells and was encapsulated by dense connective tissue. Some blood vessels and nerve fibers entered the nodule. Based on the morphology, we speculated that SIF-cell nodule might be an endocrine gland.