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Biomedical subjects

M Wang

Publications and source records attributed to M Wang.

At least 721 records · Page 40Linked to original sources
PubMed1996

Infected third branchial cleft cyst: retropharyngeal extension to the superior mediastinum.

The presentation of an infected branchial cleft cyst extending into the retropharyngeal space is extremely rare. However, differentiation of this lesion from a simple retropharyngeal abscess is important for surgical planning. The authors describe a 44-year-old woman in whom an infected third branchial cleft cyst was initially misdiagnosed as an abscess and drained surgically. Repeat surgery was necessary when the patient's symptoms recurred several weeks later.

Adult↗
PubMed1996

Research into analgesia by inhaling analgesic.

This article deals with analgesia by inhaling analgesic. According to Chinese medical theories, TCM analgesics were chosen from the literature and folk prescriptions screened and proved by analgesic tests on animals. A reasonable prescription was made up and the drug inhaled. Its analgesic effect was superior to that of dolantin injection (3 mg/kg body weight, intraperitoneal injection). Clinical trials showed its analgesic effect in 3-10 minutes and it lasted for more than 2 hours in over 70% of the cases for a total effective rate of 94.6%. The drug is absorbed quickly and acts directly on the nerve center. Its use is not addictive.

Administration, Inhalation↗
PubMed1996

Lipid peroxidation-induced putative malondialdehyde-DNA adducts in human breast tissues.

The etiology of the majority of human breast cancers is unknown; however, oxidative stress and lipid peroxidation have been suggested to play a role in breast carcinogenesis. To address this possibility, DNA adducts induced by malondialdehyde (MDA), an end product of lipid peroxidation, were analyzed in surgical specimens of normal breast tissues of 51 breast cancer patients using the nuclease P1-enhanced version of the 32P-postlabeling assay. Normal breast tissue samples from 28 noncancer patients receiving reduction mammoplasty served as controls. Two previously characterized putative MDA-deoxyadenosine (dA) and one MDA-deoxyguanosine adduct were detected in all tissue samples examined. Normal breast tissues from cancer patients exhibited significantly higher levels of the putative MDA adducts [median (42.5) and range (2.2-202.8) of relative adduct labeling x 10(9) values] than those found in noncancer controls (median, 15.67; range, 2.4-382.1; P = 0.0001, Mann-Whitney U test). Ten of the 51 cancer patients and 1 of the 28 controls were found to contain the putative MDA adducts at the level of > 1/10(7) nucleotides, a frequency comparable to that found in human liver. Age and body mass did not significantly influence the levels of these adducts. However, the presence of a previously detected benzo(a)pyrene-like DNA adduct in the breast tissues was associated with higher levels of the putative MDA-dA adducts in cancer patients (P = 0.012). The level of the putative MDA-dA adducts was significantly lower in smokers and former smokers compared to nonsmokers among cases after adjusting for age, body mass index, and status of the benzo(a)pyrene-like adduct (P = 0.009). Tumor tissues (n = 11) displayed significantly lower levels of the putative MDA adducts (median, 10.2; range, 5.3-20.6) than their corresponding normal adjacent tissues (median, 25.5; range, 10.5-138; P < 0.01). These findings provide evidence that lipid peroxidation products can accumulate in human breast tissues and reach relatively high levels in the breast tissues of women with breast cancer. There seems to be an interaction between these endogenous DNA modifications and carcinogen exposure-induced DNA adducts. Detection and quantitation of the putative MDA-DNA adducts may potentially be a useful tool in the understanding of breast cancer etiology.

Adult↗
PubMed1996

Familial occurrence of typical and severe lethal congenital contractural arachnodactyly caused by missplicing of exon 34 of fibrillin-2.

Genetic linkage studies have linked congenital contractural arachnodactyly (CCA), a usually mild heritable connective-tissue disorder, to FBN2, the fibrillin gene on chromosome 5. Recently, FBN2 mutations in two patients with CCA have been described. Here we report an A-->T transversion at the -2 position of the consensus acceptor splice site, resulting in the missplicing of exon 34, a calcium-binding epidermal growth factor-like repeat in fibrillin-2 in a mother and daughter with CCA. Significantly, the mother exhibited a classic CCA phenotype with arachnodactyly, joint contractures, and abnormal pinnae, whereas her daughter exhibited a markedly more severe CCA phenotype, which included cardiovascular and gastrointestinal anomalies that led to death in infancy. Analysis of cloned fibroblasts showed that the mother is a somatic mosaic for the exon 34 missplicing mutation, whereas all the daughter's cells harbored the mutation.

Adult↗
PubMed1996

Cytokine regulation of the matrix metalloproteinases and their inhibitors in human papillomavirus-18 transformed human prostatic tumor cell lines.

Cytokines may play a critical role in influencing the invasive and metastatic behavior of advanced cancers. To investigate the influence of cytokines on tissue inhibitor of metalloproteinase (TIMP) and matrix metalloproteinase (MMP) expression we have established cultures from prostate tissues of low Gleason sum 5 and high Gleason sum 10 cancers. We have examined the influence of different cytokines (interleukin [IL]-10, IL-4, IL-6, IL-2, and interferon-gamma) on TIMP-2, MMP-2, and MMP-9 protein and mRNA expression in human papillomavirus (HPV)-18 immortalized human prostate cell lines derived from the primary cultures. Western blot and northern blot analysis revealed that IL-10, IL-6 and IL-4 all upregulated TIMP-1 expression after 16-36 h. In contrast, IL-10 and IL-4 (but not IL-6) downregulated MMP-2 mRNA and protein levels to different degrees over 24-36 h. The levels of TIMP-2 and MMP-9 protein and mRNA were not influenced substantially by any of the cytokines. Also, IL-2 and interferon-gamma had little or no effect on any of these genes. In sum, the data showed that IL-10 (or IL-4) upregulated TIMP-1 and coordinately downregulated MMP-2 expression. Thus, cytokines might control the molar ratio of TIMP-1 and MMP-2 to influence the level of protease activity and perhaps the invasive behavior of malignant cells in vivo.

Adenocarcinoma↗
PubMed1996

Effects of alendronate and taxol on PC-3 ML cell bone metastases in SCID mice.

The combined influence of alendronate, a bisphosphonate compound, and taxol on the establishment and growth of human PC-3 ML subclones injected intravenously via the tail vein in SCID mice was investigated. The pretreatment of SCID mice with alendronate (0.04-0.1 mg/kg twice weekly or 0.1 mg/kg weekly) partially blocked the establishment of bone metastases by human PC-3 ML cells and resulted in tumor formation in the peritoneum and other soft tissues. However, alendronate pretreatment of mice (0.1 mg/kg twice weekly or weekly) and dosing along with taxol (10-50 mg/kg/day, twice weekly, or weekly) blocked the growth of PC-3 ML tumors in the bone marrow and soft tissues in a statistically significant manner and improved survival rates significantly (p < 0.001) by 4-5 weeks. ELISAs and zymography of matrix metalloproteinase production in vitro and in vivo showed that alendronate and taxol alone partially inhibited metalloproteinase production, but that taxol in combination with alendronate totally blocked protease production and release. The combined activities of alendronate and taxol appeared to inhibit the establishment and growth of tumors in SCID mice, perhaps, in part, as a result of inhibition of protease production and release.

Alendronate↗
PubMed1996

[Methodology for controlling healthy worker effect on coal miners' mortality].

This paper reports how to control the healthy worker effect (HWE) in a mortality study of coal miners. We used four methods, namely (1) age-specific corrective coefficient, (2) proportional mortality ratio (PMR), (3) corrective standarized mortality ratio (CSMR), and (4) a control group composed of factory workers. The results showed that all these methods could control HWE, and the total mortality in the coal miner group was significantly higher than that of the general population group (P < 0.05). However, the best way for controlling HWE awaits further studies.

Adult↗
PubMed1996

[A 5-year before-and-after comparison of lung function in asbestos workers].

A 5-year before-and-after comparison of lung function was carried out in 119 male asbestos workers. Of them 50 were healthy workers (0), 25 were patients with suspectable asbestosis (0+), 36 with Stage I asbestosis (Ias) and 8 with Stage II asbestosis (II as). The findings measured for before and after 5 years revealed that FVC, FEV and DLco declined in the four groups over the whole period of observation. The decrease in FVC and DLco was most marked and the differences were statistically significant (P < 0.05). Comparison among four groups showed that all indices of lung function in Group II as reduced significantly after 5 years (P < 0.01), indicating a rapid decrease of lung function in Group II as. It is suggested that FVC and DLco are the most sensitive indices in detecting very early abnormalities of lung function in asbestos workers.

Adult↗
PubMed1996

[Effect of birchdust on viability of alveolar macrophages and superoxide produced by alveolar macrophages in vitro].

Rabbit alveolar macrophages (AM) in vitro were used as a model in this wooddust toxicological experiment to study the effect of birchdust with different concentrations and exposure durations on the viability of AM and superoxide produced by AM. The results showed that the viability rates in three birchdust groups (400, 800, 1600 micrograms/ml) gradually decreased when the concentration at all the designed exposure durations (12, 18, 24 h) increased except the rates for the 6-hour period. On the contrary, the contents of superoxide (O2-.) at the first two durations (6, 12 h) increased rapidly and reached their highest level at the 18 hours. Moreover, the rapid increase of O2-. preceded the declination of viability rates, suggesting that birchdust toxicity in AM in vitro be probably related to dust-induced O2-. produced by AM.

Animals↗
PubMed1996

Overexpression of c-myc gene without gene amplification in human hepatocellular carcinoma.

OBJECTIVE: To clarify the relationship between c-myc gene amplification and expression in human hepatocellular carcinoma (HCC) tissue. METHODS: Levels of amplification, transcription and P62 myc expression of c-myc gene in tumor tissues and corresponding non-tumor tissues were systematically studied using Dot blot hybridization, in situ hybridization and immunohistochemical technique, respectively. The 14 pairs of specimens were resected from patients with HCC. RESULTS: The amplification of c-myc gene was not found in tumor and non-tumor tissues. Overexpression of c-myc mRNA transcription was detected in 11 tumor tissues and 10 non-tumor tissues. The positive rate of P62 myc was 85.7% (12/14) in tumor tissues and 92.9% (13/14) in non-tumor tissues, respectively. A close correlation was noticed between c-myc mRNA and P62 myc expression. The results suggested that c-myc gene overexpression was not related to its amplification. CONCLUSIONS: The overexpression of c-myc mRNA and gene product without amplification may be characteristic in HCC.

Carcinoma, Hepatocellular↗
PubMed1996

Approaches and reconstruction in skull base operation.

OBJECTIVE: To design convenient lateronasal and infrafrontal approaches or lateronasal subvolution approach to radically resect skull base tumors involving cranial cavity. METHODS: From 1987 through 1994, 22 patients with malignant tumors, 6 with benign tumors, one with a giant sphenoid sinus cyst and one with intranasal meningoencephalocele underwent the operation. Twenty-three cases had anterocranial fossa involved; 4, midcranial fossa; 2, anteromedial cranial fossa; and 1 case, posteromedial cranial fossa. Among the patients with malignant tumors, 11 underwent expansive maxillectomy and 10 had orbital contents resected. The intracranial approaches through lateronasal and infrafront (21 cases), nasal columella lateral subvolution (3 cases) and other approaches were used. RESULTS: The reconstruction of bony skull base defect in excess of 3.00 cm x 3.00 cm with total front musculocutaneous flap (8 cases), galeal and pericranial flap (5 cases) or other tissues (3 cases) has effectively prevented meningoencephalocele. Twelve cases had the dura resected in a range of 2.00 cm x 2.00 cm to 7.00 cm x 6.00 cm. Reconstruction of the dura defect with autofascia lata in 9 cases and other tissues in 3 cases effectively prevented the cerebrospinal fluid leak. Eight of 22 (36.4%) patients with malignant tumors have been alive and free of disease for 3-7 years after the operation. Six patients with benign tumors, one patient with giant sphenoid sinus cyst and one with meningoencephalocele were cured with this reconstructing method. CONCLUSIONS: Frontal musculocutaneous and pericranial flaps have advantages over free bone because of easy surviving and easy operating without occurrence of osteonecrosis and exclusive reaction.

Adolescent↗
PubMed1996

[The relationship between selenium and immunity in large bowel cancer].

44 patients with large bowel cancer were randomly divided into two groups, therapeutic and control group. The level of serum selenium, T lymphocyte subsets consisted of CD3, CD4, CD8, CD4/ CD8, NK and LAK cell activity were measured preoperation and postoperation. Simultaneously se content in tumor and normal tissue of the large bowel were measured in 35 cases. Serum se level (0.81 +/- 0.14 umol/L) was lowered in patients with large bowel cancer and increased significantly after se supplementation in the therapeutic group (P < 0.01). It was significantly different from that of the control group (P < 0.01), CD3, CD4, CD4/CD8, NK and LAK cell activity were obviously increased postoperatively in the therapeutic group and significantly different from those of the control group. The results suggest that supplement of Se can promote cell-mediated immunity in humans. In addition, Se can promote cell-mediated immunity in humans. The Se level of 22. 13 +/- 1.76 umol/g in tumor was significantly lower than that of 24.30 +/- 1.96 umol/g in normalmucosa in case of large bowel cancer (P < 0.01). This indicates that there may be a close relationship between low se level and the carcinogenesis of the colon and rectum.

Adult↗
PubMed1996

[Study of the amplification and expression of c-erbB2 oncogene in epithelial ovarian tumors].

Protooncogene c-erbB2 amplification and expression were studied in 62 cases of epithelial ovarian tumor by using immunohistochemical method and in situ hybridization. c-erbB2 gene amplification was observed in 30 of 47 ovarian cancers (63.8%) and in none of 15 benign tumors. The gene expression was found in 38 of the former and in 9 of the latter tumors. The gene amplification showed significant difference between malignant and benign tumors (P < 0.01). But for gene expression, only the strongly positive staining demonstrated significant difference (P < 0.01). There was correlation between c-erbB2 gene amplification and expression in epithelial ovarian carcionoma. The status of c-erbB2 gene amplification and expression had no relationship with histopathological types of ovarian carcinoma. The results indicate that there is extensive expression of c-erbB2 in epithelial ovarian tumors and it is over-expressed in ovarian carcinoma. Gene amplification is perhaps only one way by which c-erb2 gene is activated, and its overexpression might be one of the factors that promotes epithelial ovarian cancer development.

Carcinoma, Endometrioid↗
PubMed1996

[Effects of xueguantong on plasma endothelin and calcitonin gene-related peptide in quail atherosis model].

This paper mainly reported the antiatherogenic mechanism of action of Xueguantong on molecular level. After being established by feeding with high fat diet for 12 weeks, the quail atherosis models were given Xueguantong for 30 days. Then, determining their plasma endothelin and calcitonin gene-related peptide (CGRP) with radioimmunoassay (RIA) and observing the effects of Xueguantong on plasma endothelin and CGRP in quail atherosis models. Results showed that the plasma endothelin increased and CGRP decreased during quail atherosis formation. The plasma endothelin was decreased (P < 0.05) and CGRP was increased (P < 0.05) by using Xueguantong. It suggested that one of antiatherogenic mechanisms of Xueguantong was decreasing the endothelin and increasing the CGRP.

Animals↗