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Biomedical subjects

S Yu

Publications and source records attributed to S Yu.

At least 307 records · Page 17Linked to original sources
PubMed1996

Experimental study on the early efficacy of excimer laser with adjunctive balloon angioplasty in dog's femoral artery.

The effect of domestically-manufactured excimer laser with adjunctive balloon angioplasty in achieving revascularization and reduction of residual stenosis was assessed. 20 femoral arteries with thrombosis and occlusion from 12 dogs were subject to angiography. At first excimer laser angioplasty was done followed by balloon angioplasty. The diameter and residual stenosis of revascularized vessel were measured. The result showed that 17 out of 20 vessels (85%) were revascularized. The diameter of revascularized vessel by excimer laser were 1.22 +/- 0.14 mm, while residual stenoses were 54% +/- 5%. After adjunctive balloon angioplasty the diameter and residual stenoses were 2.04 +/- 0.16 mm and 20% +/- 7% respectively (P < 0.05 and P < 0.01). Complication in form of vasoperforation occurred in 3/20 vessels (15%). It is concluded that China- manufactured excimer laser angioplasty is effective when used for revascularization. While the reduction of narrowing and residual stenoses was enhanced after adjunction of balloon angioplasty. This method can be employed in treating peripheral occlusive disease effectively and safely.

Angioplasty, Balloon, Laser-Assisted↗
PubMed1996

Calcification of bovine pericardium: glutaraldehyde versus No-React biomodification.

BACKGROUND: Calcific degeneration is the most frequent cause of clinical dysfunction of glutaraldehyde (GA)-pretreated bioprosthetic heart valves. The No-React (NR) process has been shown to be a promising anticalcification treatment. In this comparative study, our objective was to delineate the advantages of the NR treatment over GA. METHODS: Bovine pericardial strips pretreated with GA and NR were individually incubated in calcium phosphate solution for 21 days at 37 degrees C. The pretreated bovine pericardium then was implanted subcutaneously in rats and retrieved at 14, 21, and 35 days after-implantation. Mineral and morphologic analyses were performed on each specimen. RESULTS: The NR-treated pericardium revealed significantly reduced in vitro calcification compared with the GA-treated tissue (mean tissue calcium content 1.3 +/- 0.2 versus 5.9 +/- 0.7 micrograms/mg; p < 0.001). Mineral analysis showed progressive calcification of the GA-pretreated pericardium over the period of implantation (calcium content increasing from 49.6 +/- 9.6 micrograms/mg after 2 weeks to 134.3 +/- 9.1 micrograms/mg at 5 weeks after-implantation). The NR-treated implants had calcified significantly less (p < 0.05) at each corresponding interval. Moreover, morphologic examinations demonstrated a protracted inflammatory response in the form of giant cell and mononuclear cell infiltration associated with intrinsic collagen disruption in the GA-treated tissue; the NR-treated pericardium maintained morphologic integrity with a mild inflammatory response. CONCLUSIONS: The NR biochemical process appears not only to attenuate pericardial calcification, but also to abort the host's destructive inflammatory response to the xenograft.

Animals↗
PubMed1996

No-react detoxification process: a superior anticalcification method for bioprostheses.

BACKGROUND: Glutaraldehyde pretreatment of bioprosthetic heart valves is the major pathogenic factor in their calcific degeneration. This comparative study investigates the merit of the No-React aldehyde detoxification process as an alternative modifier of xenograft tissues. METHODS: Glutaraldehyde- and No-React-pretreated porcine aortic valve cusps were implanted subcutaneously in 6-week-old rats (n = 20). At 3, 6, and 14 weeks, randomly selected animals were sacrificed and the explants underwent mineral and morphologic analyses. Glutaraldehyde- and No-React-treated bovine pericardium and porcine aortic valve cusp were incubated in fibroblast cell culture plates. Cell viability was observed under reversed microscope at 6, 24, 48, and 96 hours. Erythrosin B dye exclusion test was used to validate percent cell death. RESULTS: Pretreatment with No-React significantly inhibited calcification of aortic cusp subcutaneous implants throughout the 14-week period (mean tissue Ca2+ content = 1.3 +/- 0.7 micrograms/mg at 14 weeks.) Glutaraldehyde-treated cusps underwent protracted calcification (Ca2+ content = 190.6 +/- 89.5 micrograms/mg; p < 0.01). Morphologic findings correlated with mineral analyses. One-hundred percent of fibroblast cells survived in the presence of No-React-treated tissue, with a growth pattern indistinguishable from control cell culture (ie, in the presence of no tissue). The cells incubated with glutaraldehyde-treated tissue showed signs of nonviability by 6 hours, with 100% cell death by 48 hours. Dye exclusion tests validated these findings. CONCLUSIONS: The No-React detoxification process completely abolishes the cytotoxicity of the xenograft tissue and inhibits calcific degeneration.

Animals↗
PubMed1996

The ultrastructure of vesicle-containing cells and ER-cells of human peritoneum.

In 16 human specimens the mesothelial cells of the diaphragmatic peritoneum and the pelvic parietal peritoneum were observed by transmission electron microscopy and freeze fracture replica. There were two types of cells i.e. the vesicle-containing cells and ER-cells. The former were found only in the diaphragmatic peritoneum and contained numerous cytoplasmic vesicles. These vesicles could be alone or in clusters. The clustered vesicles were often fused to form large vacuoles which opened on the free surface of the cell, into the intercellular space, or through the basement membrane, or sometimes became secretory particles on the free surface of the cells. Some vesicles were also observed in the microvilli. The latter were only found in the pelvic parietal peritoneum and contained abundant endoplasmic reticulum. The vesicle-containing cells seemed to absorb the material from the peritoneal cavity. The ER-cells contained abundant endoplasmic reticulum and Golgi apparatus, and showed high synthetic activity, possibly related to the production of peritoneal fluid.

Adult↗
PubMed1996

A study of the three-dimensional organization of the human diaphragmatic lymphatic lacunae and lymphatic drainage units.

The peritoneal stomata, lymphatic drainage units and subperitoneal terminal lymphatics, called lymphatic lacunae, form a specialized drainage system in the diaphragm, by which absorption of fluid in bulk, particles and cells is carried out in the peritoneal cavity. The aim of this study is to elucidate the three-dimensional organization and function of the subperitoneal lymphatic lacunae and lymphatic drainage units by using lymphatic casts in the scanning electron microscope (SEM), ODO (OsO4-DMSO-OsO4) freeze fracture, conventional SEM and the transmission electron microscope (TEM). The subperitoneal lymphatic lacuna is unique for its large size and its multiple morphology and can be recognized by its broad, flattened enlargement and the blind-ends of lymphatic vessels, from which extend numerous main lymphatic vessels and side branches. These lymphatic vessels communicate with each other and form a rich lymphatic plexus under the diaphragmatic peritoneum. Two layers of lymphatic networks, i.e. the subperitoneal plexus and the deeper plexus are found in the muscular portion. Only one layer is present in the tendinous portion of the human diaphragm. The lymphatic plexus is denser in the tendinous portion than that in the muscular portion. The lymphatic lacunae occur exclusively in the muscular portion of the human diaphragm. The lumina of lymphatic lacunae are separated from the peritoneal cavity by a barrier consisting of cuboidal mesothelial cells, endothelial cells of the lymphatic lacunae and intervening connective tissue forming a lymphatic drainage unit. All these three components of the lymphatic drainage unit abut upon each other, but are not linked by specialized junctions. The cuboidal mesothelial cells frequently extend valve-like cytoplasmic processes that bridge the subperitoneal channel and make give it a tortuous course. The fibrous layer of the connective tissue is arranged in fiber bundles and gives a three-dimensional network forming the floor of the peritoneal stomata and the roof of the lymphatic lacunae. Via the fibrous network, the cuboidal mesothelial cells and the endothelial cells of the lacunae come into close contact with each other and form short subperitoneal channels which connect the peritoneal cavity with the subperitoneal lymphatic lacunae. The lymphatic drainage units may regulate the material absorption of the peritoneal stomata from the peritoneal cavity. It is suggested that the peritoneal stomata together with the subperitoneal channels, lymphatic drainage units and lymphatic lacunae comprise an important diaphragmatic lymphatic drainage system which plays an important role in the absorption of materials from the peritoneal cavity.

Diaphragm↗
PubMed1996

Copper homeostasis in rats fed on a high-sulphide diet.

The mechanism underlying the reduced Cu status in rats fed on a high-sulphide diet was investigated. Male rats aged 6 weeks were fed ad libitum on purified diets containing either 0 or 500 mg S2-/kg and demineralized water for a period of 2 weeks. The high-sulphide diet had no effect on feed intake, body-weight gain or weight of liver and kidney but significantly reduced Cu concentrations in plasma and kidney. Biliary Cu excretion was decreased significantly in rats fed on the high-sulphide diet. Apparent Cu absorption (Cu intake-faecal Cu) and true Cu absorption (Cu intake-(faecal Cu-biliary Cu)) were significantly lowered after sulphide feeding for 2 weeks. Rats fed on the high-sulphide diet excreted less Cu in urine than did the controls. We conclude that high sulphide intake reduces Cu status in rats through inhibition of Cu absorption which is reflected by a decrease in biliary Cu excretion as a secondary feature.

Animals↗
PubMed1996

Xylulose and glucose fermentation by Saccharomyces cerevisiae in chemostat culture.

Saccharomyces cerevisiae ATCC 24860 was cultivated in chemostat culture under anoxic conditions with 111.1 mmol of glucose liter-1 alone or with a mixture of 66.7 mmol of xylulose liter-1 and 111.1 mmol of glucose liter-1. The substrate consumption rate was 5.4 mmol g of cells-1 h-1 for glucose, whereas for xylulose it was 1.0 mmol g of cells-1 h-1. The ethanol yield decreased from 0.52 carbon mole of ethanol produced per carbon mole of sugar consumed during the utilization of glucose alone to 0.49 carbon mole produced per carbon mole consumed during the simultaneous utilization of xylulose and glucose, while cell biomass was maintained at 2.04 to 2.10 g liter-1. Xylulose coutilization was accompanied by a shift in product formation from ethanol to acetate and arabinitol. Xylulokinase activity was absent during glucose metabolism but detectable during simultaneous utilization of xylulose and glucose. Xylulose cometabolism resulted in increased in vitro activity of pyruvate decarboxylase and an increased concentration of the intracellular metabolite fructose 1,6-diphosphate without significant changes in the concentrations of 6-phosphogluconate and pyruvate. The results are discussed in relation to (i) altered enzyme activities and (ii) the redox flux of the cell.

Glucose↗
PubMed1996

Batroxobin accelerates lipid accumulation of peroxidized low density lipoprotein in mouse peritoneal macrophages.

Mouse peritoneal macrophages were incubated in DMEM medium with batroxobin (DF-521) to determine the effect of batroxobin on the internalization of peroxidized low-density lipoprotein (pox-LDL) by transmission electron microscopy. Although the morphology of the mouse peritoneal macrophages after incubation with DMEM, normal LDL (n-LDL) and n-LDL plus batroxobin was similar to that of the cells before incubation, they exhibited numerous cytoplasmic lipid droplets after incubation with pox-LDL for 4 h. After addition of batroxobin to the medium containing pox-LDL, the production of lipid droplets in the mouse peritoneal macrophages was tremendously accelerated. Batroxobin accelerates the phagocytosis and degradation of pox-LDL by macrophages.

Animals↗
PubMed1996

Experience in prevention of serious complications of laparoscopic cholecystectomy.

OBJECTIVE: To study the causes and prevention of the complications of laparoscopic cholecystectomy (LC). PATIENTS AND METHODS: Based on experience with 2 428 cases, the following should be paid attention to when dissecting and separating adhesions around the gallbladder and of the Calot's triangle. The best method for the prevention of mistaking the common bile duct (CBD) for the cystic duct is to find the junction of the cystic infundibulum and duct, separate the gallbladder wall along the infundibulum, and transect the cystic duct at the junction with the infundibulum. If dense adhesions around the gallbladder or of the Calot's triangle are met with, LC should be abandoned and open the cholecystectomy (OC) should be used instead. In separating the Calot's triangle, blunt dissection should be used to avoid burning the extrahepatic bile duct (EHBD), and blind hemostasis should be avoided. If the cystic artery lies in the upper part and the back of the cystic duct, the cystic duct should be dissected out, clipped and cut first, then the cystic artery be dealt with. If the cystic artery is in the front part of the pedicle of the gallbladder, the artery should be separated, clipped and cut first. Injury to the adjacent organs may be avoided by using electric coagulating hook correctly and avoiding accidental damage to the viscera, and keeping from viscera injury due to current chemotaxis in the closed cavity of the body. RESULTS: A total of 2427 patients were cured. One patient died of frequent episodes of supraventricular tachycardia and pneumonia on the 21st day after LC. CONCLUSION: If LC surgeons follow the above said principles of LC technique. LC is very safe for patients with benign diseases of the gallbladder.

Adolescent↗
PubMed1996

[Detection of minimal disease in bone marrow from non-Hodgkin's lymphoma and its clinical significance].

OBJECTIVE: Using some molecular biological techniques, we studied the clinical significance of minimal disease (MD) in bone marrow (BM) from the patients with non-Hodgkin's lymphomas (NHL). METHOD: Polymerase chain reaction (PCR) and restriction enzymes map analysis of PCR products (PCR/RE) were used to find the clonal gene rearrangement of IgH and TCR(gamma) for detecting MD in BM. The BM samples from 35 patients with NHL were examined by these techniques. RESULTS: The incidences of MD in BM were 66% (23/35), 51% (18/35) in IgH group and 49% (17/35) in TCR(gamma) group. While the frequency of BM involvement detected by BM smear was 26% (9/35). Not only majority of patients with NHL in this series but also above half of patients (7/12) in stage I and II had MD in their BM. MD was related to histologic grade and systemic symptoms (P < 0.05). The incidence tended to be increased gradually from stage I to stage IV, and these patients with MD to be poorer in response rate, mortality and recurrence rate, though without statistical significant correlation. CONCLUSIONS: NHL is a systemic disease. MD in BM may be a prognostic factor in NHL.

Base Sequence↗
PubMed1996

[Studies on microcystin contents in different drinking water in highly endemic area of liver cancer].

In order to study the pollution with microcystin (MC), a potent liver promoter, in drinking water in highly endemic area of liver cancer, cyanobacteria and its product MC were detected in drinking water in Haimen, Jiangsu Province during 1992 to 1993. Oscillatoria was identified as the most common species of cyanobacteria in pond-ditch and river water in Haimen, Jiangsu Province, which can produce MC. MC was detected in two of 65 water samples with high performance liquid chromatography, liquid chromatography and mass spectrography. In addition, studies were conducted in 989 samples collected from drinking water in Haimen, Jiangsu Province and more sensitive ELISA was used to detect their MC contents. Results showed proportions of samples with positive MC (greater than 50 pg/ml) were 17.3%, 31.9%, 4.3% and 0 for pond-ditch, river, shallow and deep well water, respectively, with average contents of 101, 160, 68 and 0 pg/ml, respectively. Proportions of positive MC samples and average MC contents for pond-ditch water were significantly greater than those in shallow and deep well water. It suggests studies on relationship between MC and liver cancer should be conducted further.

Carcinogens↗
PubMed1996

[A survey of moniliformin in rice and corn sampled from the areas with and without Keshan disease].

Moniliformin (MF) was determined quantitatively for 123 samples of rice and corn collected from the areas with Keshan disease in Sichuan and Yunnan provinces and the areas without Keshan disease in Beijing using thin layer chromatography (TLC) and high performance liquid chromatography (HPLC). Results showed MF was found in 8.8% of the 83 rice samples from the areas with the disease, ranging from 73.5 to 265.3 micrograms/kg, and in 2.5% of the 40 sample from the areas without the disease with an average of 179.5 micrograms/kg. MF was found in 81.4% of the 43 corn samples from the areas with the disease, ranging from 52.3 to 1116.0 micrograms/kg, and in 9.7% of the 61 samples from the areas without the disease ranging from 73.3 to 1082.2 micrograms/kg. There was significant difference between positive proportions for MF in rice and corn from the diseased and non-diseased areas, but no significant difference between their average amount of MF. Differences in contamination of MF between rice and corn was much greater than that between different areas.

Cardiomyopathies↗
PubMed1996

[Persistent and recurrent gynecologic malignant tumor treated within one year: analysis of 1,753 cases from 61 hospitals in China].

OBJECTIVE: To analyze the causes of persistent and recurrent gynecologic malignant tumors treated within 1 year. METHODS: 20,974 cases of gynecologic malignant tumors from 61 hospitals in 24 provinces admitted between 1983-1993 were collected. Out of the total, 1753 cases treated within 1 year with tumor persistence, recurrence or death were retrospectively analysed. RESULTS: The ovarian carcinoma and vaginal cancer had the highest rates of tumor persistence, recurrence or death. Among the 1587 cases of tumor persistence or recurrence, pathological grading were not performed in 56.52% of the cases. For surgical treatment, inappropriate operation were done in 81.68% (767/939) of the ovarian carcinoma, 64.38% (103/160) of the cervical carcinoma, and 70.08% (89/127) of the endometrial cancer. 55.47% (532/959) of ovarian cancer and 38.31% (59/154) of choriocarcinoma and malignant mole had insufficient chemotherapy. For cervical cancer, 54.90% (235/396) of the cases did not receive enough doses of radiotherapy. CONCLUSION: Accurate staging and standardized therapy are important for improving 1 year survival rate in malignant gynecologic tumors.

Choriocarcinoma↗
PubMed1996

[Measurement and analysis of bone mineral density of lumbar vertebrae and alveolar bone in patients with periodontitis].

Periodontitis and osteoporosis are world-wide diseases. It has been suggested that periodontitis and osteoporosis might be related. In order to evaluate this possible relationship, the bone mineral density (BMD) of the lumbar vertebrae and alveolar bone in 21 patients with severe chronic periodontitis (CP), 11 patients with rapidly progressive periodontitis (RPP), and 14 normal persons was measured by dual photon absorptiometry. The results show: The alveolar BMD of periodontitis patients is significantly lower than normal persons. The lumbar vertebrae BMD has not significantly different between periodontitis patients and normal persons. The lumbar vertebrae BMD and alveolar BMD have not significantly different between CP and RPP. We therefore suggest that the alveolar BMD and lumbar vertebrae BMD have not relationship, the osteoporosis is not an important factor in the pathogenesis of periodontitis.

Adult↗
PubMed1996

[In vitro culture of neonatal mouse calvaria as a model for study of bone resorption].

We established the in vitro culture system of neonatal mouse calvaria. Bone resorption was determined by the following examinations; (1) the release of calcium from the calvaria into the medium was measured by use of atomic absorption spectrophotometer, and the treated to control ratio was calculated and used as an index of bone resorption; (2) the concentration of osteocalcin in the cultured medium was determined by radioimmunoassay; (3) histological examination. By combined use of the examinations, we were able to objectively determine the bone resorption of cultured calvaria.

Animals↗
PubMed1996

[Relationship between c-erbB2 oncoprotein expression and biologic behavior of cervical squamous cell cancer].

OBJECTIVE: To investigate the relationship between c-erbB2 oncoprotein expression and biologic behavior and prognosis of cervical squamous cell cancer. METHOD: Immunohistochemistry was used to examine the c-erbB2 oncoprotein expression in 62 cases of cervical sequamous cell cancer, 9 cases of cervical iutraepithelical neoplasia (CIN) and 10 cases of normal epidermal tissues section of the cervix. RESULTS: Nineteen of 62 cancers and 1 of 9 cases of CIN showed positive staining. None of normal epithelium showed positive. In cervical cancer the positive staining rate of c-erbB2 oncoprotein in grade 1, 2 and 3 was 12.5%, 27.6% and 52.9% respectively. There was a significant difference between grade 1 + 2 and grade 3 (P = 0.019). In 20 cases operated on, 3 of 6 cases with positive staining had pelvic lymph node metastasis, while only 1 of 14 cases with negative staining had metastasis (P = 0.032). The 5-year survival rate of positive staining group was significantly lower than that of negative group (31.5% Vs 74.4%, P < 0.001). CONCLUSION: The c-erbB2 oncoprotein expression on cervical sequamous cell cancer was related to agressive biologic behavior and poor prognosis.

Adult↗