Search PubMed⌕ Search

Biomedical subjects

M C Wu

Publications and source records attributed to M C Wu.

At least 91 records · Page 5Linked to original sources
PubMed1990

The biopathologic characteristics of DNA content of hepatocellular carcinomas.

A gross morphologic classification of 66 small hepatocellular carcinomas (SHCC, less than or equal to 3 cm in diameter) was made and DNA content of 30 SHCC and 26 large hepatocellular carcinomas (LHCC, greater than 3 cm in diameter) was determined by image analysis technology. The three types of SHCC are as follows: type I, noncapsule type; type II, capsule type; and type III, infiltrative type. Of the SHCC, 73.3% had diploid DNA content, and 84.6% of LHCC had aneuploid DNA content. The postoperative 5-year survival rate of patients with SHCC was 62.1%, which is higher than the rate of 27.7% of patients with LHCC. There was no correlation between tumor size and serum alpha-fetoprotein (AFP) levels. The results suggest that the period when SHCC are 3 cm in size may be important as the changes of DNA stemlines and biological characteristics would occur then. The SHCC of less than 3 cm reflect relatively benign biological behavior of early hepatocellular carcinoma and this period is the best opportunity for the clinician to get the best prognosis. Currently determination of serum AFP is still one of the possible and effective methods to early finding SHCC.

Adult↗
PubMed1990

Expression of human granulocyte-macrophage colony-stimulating factor gene in insect cells by a baculovirus vector.

A plasmid pAc373GM-CSF was constructed and co-transfected into Spodoptera frugiperda (Sf9) cells with wild-type Autographa californica nuclear polyhedrosis virus (AcNPV) DNA. The recombinant virus vAc373GM-CSF was identified and purified by several rounds of plaque hybridization. By assaying the culture medium, we demonstrated recombinant virus infected Sf9 cells expressing hGM-CSF. Recombinant hGM-CSFs with apparent molecular masses of 14.5, 15.5 and 16.5 kDa were detected by the Western blot method. All 3 forms have biological activity of hGM-CSF. Following N-glycanase treatment, a single band of 14.5-15.5 kDa appeared in SDS-PAGE. Western blot analysis of expression in Sf9 cell treated with tunicamycin revealed only the presence of the 14.5 kDa species. Thus, the signal sequence of recombinant hGM-CSF could be recognized and cleaved by infected insect cell and the resultant molecule secreted into the media.

Animals↗
PubMed1990

Respiratory function in patients with spinal cord injuries: effects of posture.

The purpose of this study was to evaluate the respiratory function of spinal cord injuries (SCI) during different postures. Measurements were performed with a Fukuda PM 80 spirometer on 31 chronic stable SCI and 22 normal controls. Among the SCI patients, there were 12 quadriplegics and 19 paraplegics. The respiratory parameters, including forced vital capacity (FVC) and forced expiratory volume during first second (FEV1.0) were collected in each subject during supine, sitting and standing postures. The results revealed that SCI patient had impaired FVCs (p less than 0.05), the degree of impairment depending upon the level of cord injury (r = 0.81). The FEV1.0/FVC ratio of SCI was normal. For quadriplegics, the FVC during sitting and standing fell on 30 to 50% of normal values. The FVCs of paraplegics during all postures were around 80% of the predicted values. The FVC in the control group was reduced by 5 to 7% when changing postures from erect to supine. This study concludes that respiratory impairment does occur in SCI. The results obtained display a typical pattern of restrictive pulmonary impairment. The severity of the impairment is affected by the level of cord damage and is posturally dependent.

Adult↗
PubMed1990

Experience with orthotopic rat liver transplantation.

300 orthotopic liver transplantations in rats were performed for a variety of reasons. Male rats including Lewis, ACI, Wistar, and SD, with a body weight of 150 to 400 g, were used as liver donors and recipients. A midline abdominal incision was performed in both donor and recipient animals. The donor's liver was perfused through the aorta abdominalis. The recipient's liver was flushed via the protal vein (PV) with 2 ml of lactated Ringer's solution immediately after occlusion of the PV to make intrahepatic blood enter the circulation. The bile duct was reconstructed by end-to-end anastomosis via a Teflon catheter. The cuff technique was applied to anastomoses of the infrahepatic vena cava (VC) and PV. The suprahepatic VC was anastomosed using either suture or cuff technique. The operative success rate was 92.7% (278/300) on the average and 1-week survival rate 88.4% (199/225) in isografting. The model proved reliable for studies of liver transplantation.

Animals↗
PubMed1990

Aspects of treatment in alpha 1-antitrypsin deficiency: insights derived from a Swedish PiZZ series.

Data were analysed on 158 adult Swedish alpha 1-antitrypsin deficient individuals homozygous for the proteinase inhibitor allele (PiZZ), followed from 1963-1982. The initial forced expiratory volume in one second (FEV1) increased from 1.4 l in the early cohort to 1.9 l (p less than 0.001) in the late cohort of the study period but mean age (47 yrs) and the percentage of smokers (72%) remained unchanged. Smokers were found to have significantly lower FEV1 levels (p less than 0.01) and higher (p less than 0.005) mortality than non-smokers. The differences between current and ex-smokers in mortality and FEV1 level, however, were not significant. Longitudinal analysis of FEV1 rates of decline in 80 cases with follow-up FEV1 measurements failed to detect any significant difference between current and ex-smokers but investigations were performed late in the disease process. Low initial FEV1 value was found to be significantly associated with increased mortality (p less than 0.005). In order to detect a 40% difference in the rate of FEV1 decline as an outcome variable, 253 patients plus controls must be included in follow-up studies of replacement therapy. With mortality of severely affected patients as outcome variable only, 144 treated and untreated patients would be required. The need for earlier diagnosis and intervention against smoking in these cases is emphasized.

Adolescent↗
PubMed1989

Lipoperoxidation and T-cell leukemia of childhood. Effects of indomethacin.

Serum thiobarbituric acid (TBA) reactivity for lipoperoxidation products was assessed at diagnosis in children with T-cell and common acute lymphocytic leukemia (ALL) and T-lymphoblastic lymphoma. Comparisons were made among these groups and with healthy controls. Mean TBA reactivity (mumol malondialdehyde/L serum) was increased (P less than 0.01) in the T-cell leukemia group versus common ALL and T-lymphoblastic lymphoma patients and controls, respectively. The increase in lipoperoxidation products in T-cell ALL appeared to bear a positive relation to peripheral leukocyte counts, and was accompanied by increased serum prostaglandin E2 (PGE2) levels in most representative cases. Indomethacin added to a childhood T-cell ALL line (SUP-T3), at a concentration known to inhibit prostaglandin synthesis in vitro (i.e., 3 micrograms/mL), effected significant increases in the numbers of natural killer (NK; Leu-11+ and Leu-19+) cells (P less than 0.01) and B-lymphocytes (P less than 0.05), and significant decreases in cell viability (P less than 0.01). Indomethacin may be a useful agent for enhancing the antileukemic immune response in T-cell ALL.

Child↗
PubMed1989

Inhibition of myeloid differentiation by inhibitors of ADP-ribosylation.

Inhibitors of ADP-ribosylation inhibited the myeloid differentiation of murine myelomonocytic leukemia, WEHI-3BD+ cells induced by granulocyte colony-stimulating factor. Benzamide, at 2.0 mM, inhibited 50% of the WEHI-3BD+ cell differentiation but had no significant effect on the proliferation. However, benzylaminododecylguanine hydrochloride and p-methoxylbenzylaminodecamethylene guanidine sulfate at 2.0 and 2.2 microM, respectively, inhibited 50% of proliferation but had no effect at all on differentiation. The differential effects of inhibitors provide a model to study the role of ADP-ribosylation in myeloid differentiation.

Adenosine Diphosphate Ribose↗
PubMed1989

Expression of glycoconjugates in intrahepatic cholangiocellular carcinoma.

Twenty cases of intrahepatic cholangiocellular carcinoma (IHCCC) were studied by lectin histochemistry for their glycoconjugate expression. Combined alcian blue-peroxidic acid Schiff (ABPS) staining was also made for mucins in these tissues. Results showed that epithelial cells of intrahepatic bile ducts contained varied quantity of DBA, WGA, LCA, Con A, PHA, RCAI, BLAI, SJA, SBA, PSA and UEAI receptors but no PNA receptors. Lectin receptors were present at varying rates; 100% (Con A), 95% (PSA), 90% (LCA), 95% (WGA), 30% (BSAI), 35% (DBA), 65% (PHA), 74% (PNA), 85% (RCAI), 35% (SBA), 25% (SJA) and 55% (UEAI), respectively. The positive rates in well-differentiated IHCCC were significantly higher than those in either moderately or poorly-differentiated IHCCC. The distribution of lectin receptors in IHCCC was obviously different from that in peri-carcinomatous, cirrhotic and normal liver, and also differed from that in epithelial cells of normal intrahepatic bile ducts. All larger ducts were stained by ABPS and were mainly blue colour, while only 80% of IHCCC were positive for ABPS staining. Most of them were blue, others were red or purple. The results suggest that the expression of glycoconjugates had changed after the neoplastic transformation of bile duct cells.

Adenoma, Bile Duct↗
PubMed1989

Characteristics of the distribution of lectin receptors in intrahepatic cholangiocellular carcinoma.

The receptors of peanut agglutinin (PNA), Dolichos biflorus agglutinin (DBA) and Ulex europaeus agglutinin I (UEA-I) were localized in intrahepatic cholangiocellular carcinoma, hepatocellular carcinoma, intrahepatic bile ducts and normal, cirrhotic and pericarcinomatous liver using the avidin-biotin-peroxidase complex method. It was found that epithelial cells of normal bile ducts had many UEA-I receptors, fewer DBA receptors and no PNA receptors. The positive rates of PNA, UEA-I and DBA receptors in 18 cases of intrahepatic cholangiocellular carcinoma were 88.9%, 61.1% and 33.3% respectively, which were significantly higher than those in hepatocellular carcinoma (16.0%, 4.0% and 4.0% respectively). Hepatocytes in normal, cirrhotic and pericarcinomatous liver had no receptors for these three lectins. It is suggested that lectin receptor distribution in intrahepatic cholangiocellular carcinoma is obviously different from that in normal bile duct cells and in hepatocellular carcinoma, and might be used as an auxiliary index in its clinical diagnosis.

Adenoma, Bile Duct↗
PubMed1989

Milk and fat production in dairy cattle influenced by advanced subclinical bovine leukemia virus infection.

Genetic potentials (pedigree-estimated breeding value) for milk and for fat were compared in cows grouped according to subclinical stage of bovine leukemia virus infection. Genetic potential for milk production was significantly greater in seropositive cows with persistent lymphocytosis (622 +/- 72 kg) and in seropositive hematologically normal cows (554 +/- 34 34 kg) than in seronegative herdmates (418 +/- 53 kg). When 305-day twice-daily-milking mature equivalent milk production records for the current lactation were adjusted for genetic potential, bovine leukemia virus-infected cows that were hematologically normal had significantly greater milk production than did seronegative herdmates, suggesting that early bovine leukemia virus infection was positively associated with milk yield. Genetic potential for fat production was significantly greater for cows with persistent lymphocytosis (21 +/- 2 kg) than for other seropositive (16 +/- 1 kg) and seronegative herdmates (13 +/- 2 kg); however, 305-day twice-daily-milking mature equivalent fat production for the current lactation was not significantly different between the groups. Thus, cows with persistent lymphocytosis did not produce fat according to their genetic potential. As an apparent consequence of tendencies for greater milk yield and less fat production, milk fat percentage was significantly reduced in cows with persistent lymphocytosis (3.33 +/- 0.09%) and other seropositive cows (3.48 +/- 0.05%) relative to seronegative herdmates (3.67 +/- 0.07%). These results suggest a need to reevaluate the economic impact of bovine leukemia virus infection on the dairy industry.

Animals↗
PubMed1989

Joint report of the Third International Bovine Lymphocyte Antigen (BoLA) Workshop, Helsinki, Finland, 27 July 1986.

Two hundred and eighty-two alloantisera were submitted by 20 participating laboratories from 13 countries and tested against lymphocytes of 1298 cattle. The cell panel consisted of samples from 38 Bos taurus breeds, 11 Bos taurus crossbreeds, 4 Bos indicus breeds, 6 Bos taurus x Bos indicus, and a variety of other crossbred populations. Using a standardized lymphocytotoxicity test, all 17 previously identified BoLA specificities were confirmed. The workshop produced agreement on 16 new lymphocyte alloantigenic specificities. Three of the new specificities behaved as splits of previously identified BoLA specificities. Four of the new specificities behaved as alleles at the agreed BoLA-A locus. Seven new specificities are tentatively assigned to the BoLA-A locus but require further definition. Two new specificities may represent products of a second closely-linked BoLA locus.

Animals↗
PubMed1989

Effect of initial length of uterus per embryo on fetal survival and development in the pig.

Influence of initial length of uterus available to each embryo on its subsequent survival and development was determined by systematic restriction of the length available to each potential embryo. Fifty-seven pregnant crossbred gilts were laparotomized at d 3 of gestation, length of uterine horns was measured in situ and corpora lutea (CL) were counted. In Exp. 1, uterine space available to each potential embryo was restricted by ligating one uterine horn 5 cm from the tip per CL. Uteri were examined at d 20, 25 or 50. In Exp. 2, one uterine horn was ligated on d 3 at 10, 20 or 30 cm from the tip per CL and uteri were examined at d 50. Embryos in the restricted section (RS) had a specific mean uterine length available to each potential embryo of 5, 10, 20 or 30 cm. Embryos in the nonrestricted section (NRS) had a variable mean uterine length available to each potential embryo of 44 +/- 4 cm. When embryos were restricted to 5 cm, the proportion of surviving fetuses at d 20, 25 and 50 was 61, 12 and 8%, respectively, whereas in combined NRS it was 82%. When the uterus was examined at d 50 after restricting embryos to 10, 20 or 30 cm/CL, 25, 33 and 52% of fetuses survived; in combined NRS survival was 71%. Each fetus surviving to d 50 in RS was associated with 36 cm of initial uterine length but fetal survival was not associated with number of CL. In RS, 59% were female fetuses and in NRS 50% were females.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1989

Estimation and comparison of changes in the presence of informative right censoring: conditional linear model.

A general linear regression model for the usual least squares estimated rate of change (slope) on censoring time is described as an approximation to account for informative right censoring in estimating and comparing changes of a continuous variable in two groups. Two noniterative estimators for the group slope means, the linear minimum variance unbiased (LMVUB) estimator and the linear minimum mean squared error (LMMSE) estimator, are proposed under this conditional model. In realistic situations, we illustrate that the LMVUB and LMMSE estimators, derived under a simple linear regression model, are quite competitive compared to the pseudo maximum likelihood estimator (PMLE) derived by modeling the censoring probabilities. Generalizations to polynomial response curves and general linear models are also described.

Analysis of Variance↗
PubMed1989

Rehepatectomy for treating primary liver cancer.

From January 1960 to June 1987, 41 cases underwent reoperation for relapse of liver cancer. Hepatectomy was performed twice in 39 cases, three and four times each in one case. The 1,3 and 5-year survival rates after the first operation were 100%, 69.58% and 54.68% respectively, while those after the second operation were 75.0%, 34.62% and 34.62% respectively. The preliminary results of rehepatectomy are thus encouraging. The indicators for reintervention, types of operation, prophylactic measures against tumor recurrence and metastases, and evaluation of rehapatectomy are discussed.

Adolescent↗
PubMed1989

Small hepatocellular carcinoma. DNA content and biological characteristics.

The DNA content of 12 small hepatocellular carcinomas (SHCC, less than 3 cm in diameter) and 26 large hepatocellular carcinomas (LHCC) was quantitatively determined by means of TV-image analysis. The results showed that 8 patients (66.7%) with SHCC had DNA stem lines in diploid (2C), and 24 (92.3%) with LHCC had DNA stem lines in aneuploid (AN) (P less than 0.01). The incidences of tumor capsule breaking and cancerous thrombosis were 16% and 20% respectively in SHCC, significantly lower than 84% and 80% in LHCC (P less than 0.01). The 5-year survival rate was 75% in patients with SHCC after operation, much higher than 46.2% in patients with LHCC. No relations were found between DNA content, tumor size, pathological grading and serum AFP values of HCC. The results suggest that SHCC less than 3 cm in diameter reflects the early changes of biological characteristics; HCC of 3 cm in size may be at an important period when the changes of DNA stem lines and biological characteristics would occur; SHCC is possible to be determined by serum AFP values; and that the survival rate of the patients can be further improved by early finding and treatment of SHCC less than 3 cm in diameter.

Carcinoma, Hepatocellular↗