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M X Wang

Publications and source records attributed to M X Wang.

At least 55 records · Page 3Linked to original sources
PubMed1993

[Functional changes of hypothalamic-pituitary target gland axes and their clinical significance].

We examined the function of hypothalamic-pituitary target gland axes in 88 cases with epidemic hemorrhagic fever (EHF). It was found that all the three endocrine axes i.e. hypothalamic-pituitary-adrenocortical axis, hypothalamic-pituitary-thyroid axis and hypothalamic- pituitary-gonadal axis showed some functional impairment. In acute phase there were increased plasma ACTH, FSH and LH levels, which might be attributed to stress reaction in EHF patients. Most cases showed low or weak response of TSH to TRH and delayed response of LH to LHRH; some of the cases did not respond to 1mg of glucagon. These manifestations might be related with poor reserve of anterior pituitary or to disordered regulation of endocrine axes. The increased plasma cortisol and estradiol and the decreased plasma T3, T4 as well as testosterone during acute phase may have important clinical significance. Hence we suggest that in any case glucocorticosteroids should not be abused and that in severe patients thyroxine and durabolin should be administered to improve immunity and hepato-renal function.

Adult↗
PubMed1993

[Pathological characteristics of early gastric cancer in 1477 Chinese patients].

Pathological characteristics of early gastric cancer in Chinese patients were analyzed. The 1477 cases were collected from 55 hospitals in China. The peak age of early gastric cancer patients was between 50-59 years old. The incidence in female before 50 years old was higher than that in male but reversely after this age. Highly differentiated carcinomas were more frequently found in those cancer foci of < or = 0.5 cm in diameter. It was also detected that the bigger of its size the deeper of its infiltration was in those cancer foci between < 6 cm. In these early gastric cancers, type IIc was the commonest one (39.5%) whereas the least one was type I (4.0%). The most common site was in lower part of the stomach and less found in the upper part. Prognosis of the highly differentiated carcinoma was better than that of others. More signet ring cell carcinomas were found in early gastric cancer than in advanced cases, especially in the intramucosal cancers. Lymphatic metastasis was more (17.0%) in type IIc+III and the least is in type I (3.6%). Comparing with the Japanese cases of early gastric cancer, it was found that the peak age of early gastric cancer patients in Chinese was 10 years younger than that in Japanese patients. In the latter, its highest incidence age was 70 years old and most of them occurred in middle part of the stomach. In Japanese patients, type III and mucinous adenocarcinoma of EAG was hardly found.

Adenocarcinoma↗
PubMed1992

A whole genome approach to in vivo DNA-protein interactions in E. coli.

The increasingly rapid pace at which genomic DNA sequences are being determined has created a need for more efficient techniques to determine which parts of these sequences are bound in vivo by the proteins controlling processes such as gene expression, DNA replication and chromosomal mechanics. Here we describe a whole-genome approach to identify and characterize such DNA sequences. The method uses endogenous or artificially introduced methylases to methylate all genomic targets except those protected in vivo by protein or non-protein factors interfering with methylase action. These protected targets remain unmethylated in purified genomic DNA and are identified using methylation-sensitive restriction endonucleases. When the method was applied to the Escherichia coli genome, 0.1% of the endogenous adenine methyl-transferase (Dam methylase) targets were found to be unmethylated. Five foreign methylases were examined by transfection. Database-matched DNA sequences flanking the in vivo-protected Dam sites all fell in the non-coding regions of seven E. coli operons (mtl, cdd, flh, gut, car, psp and fep). In the first four operons these DNA sequences closely matched the consensus sequence that binds to the cyclic AMP-receptor protein. The in vivo protection at the Dam site upstream of the car operon was correlated with a downregulation of car expression, as expected of a feedback repressor-binding model.

Amino Acid Sequence↗
PubMed1992

An ocular melanoma-associated antigen. Molecular characterization.

Monoclonal antibody (MAb) 8-1H defines a highly conserved ocular melanoma-associated antigen. Based on a potential binding site of MAb8-1, we identified, molecularly cloned, and sequenced the gene, encoding this melanoma-associated antigen from a uveal melanoma copy DNA library. Nucleotide sequence analysis of the melanoma-associated antigen revealed characteristics of a membrane-bound protein of 238 amino acids (approximately 25 kd) with four transmembrane domains. The sequence of the ocular melanoma-associated antigen is identical to the sequence of a recently reported cutaneous melanoma-associated antigen, substantiating our previous studies regarding common antigens between ocular and cutaneous melanoma. In addition, the melanoma-associated antigen shares sequence homology with a number of transmembrane proteins that appear to be involved in growth regulation. The implication of the biological function of this ocular melanoma-associated antigen, its relevance to the malignant phenotype, and clinical applications of the molecular characterization of this melanoma-associated antigen are described.

Amino Acid Sequence↗
PubMed1992

Identification and characterization of a 30K glycoprotein of herpes simplex virus type 2.

A herpes simplex virus type 2 (HSV-2) type-specific monoclonal antibody (MAb), CH-A9, precipitated a glycoprotein with an M(r) of approximately 30,000 (g30K) from extracts of HSV-2-infected BHK cells labelled with [3H]leucine, [14C]fructose or [3H]glucosamine. The M(r) of this glycoprotein is lower than those of other HSV glycoproteins. Immunoassays of BHK cells infected with HSV-1-HSV-2 intertypic recombinants localized the gene encoding the target antigen of MAb CH-A9 to the unique long (UL) region at map units 0.490 to 0.564. Tunicamycin effectively inhibits N-linked glycosylation of g30K, which suggests that g30K may be modified by addition of N-linked oligosaccharides and that the amino acid sequence may contain Asn-X-Ser or Asn-X-Thr. The g30K was also purified on an immunoadsorbent column consisting of MAb CH-A9 linked to Sepharose 4B and was shown to be an HSV-2 type-specific antigen by indirect ELISA. The glycoprotein could induce HSV-2 type-specific neutralizing antibody in BALB/c mice. This evidence suggests that g30K may be a novel glycoprotein of HSV-2.

Animals↗
PubMed1992

Preparation and characterization of the monoclonal antibodies against Japanese encephalitis virus.

Six mouse monoclonal antibodies (MoAbs) against Japanese encephalitis virus (JEV) were prepared and analyzed with indirect immunofluorescence assay (IFA), enzyme linked immunosorbent assay (ELISA), haemagglutination inhibition test (HI), neutralization test (NT), antibody dependent cell mediated cytotoxicity (ADCC) assay, antigenic site specific analysis and relative affinity measurement. These MoAbs could be divided into three classes by indirect immunofluorescence cross reactivity among four flaviviruses, 2H4, 2F2, and nG2 were type specific; 2D2 and mC3 were subgroup specific; and mG9 was family specific. 2H4 and 2F2 had higher neutralization activity, 2D2 and mC3 had the function of inducing ADCC effect, mG9 had higher titer in HI. The six MoAbs recognized five antigenic sites on JEV envelope glycoprotein, 2H4 and 2F2 recognized the same or very similar antigenic site and their relative affinity was ranked as: nG2 > 2H4 > 2D2 > mG9 > 2F2 > mC3.

Animals↗
PubMed1992

Endothelial cell antigens recognized by IgA autoantibodies in patients with IgA nephropathy: partial characterization.

Antibodies directed against endothelial cells (AECA) have been described in IgA nephropathy. We have previously measured AECA of the IgA subclass (AECA-IgA) in the sera of patients with glomerulonephritis by an ELISA method, and have shown that patients with IgA nephritis (IgA N) and lupus nephritis (LN) had significantly greater AECA-IgA activity compared with normal controls [1]. In the current study, on Western blotting of the EC membrane components, 6 of 18 (33%) IgA N sera positive for AECA-IgA bound to molecules of 135 and 116 kDa and 10 of 18 (56%) to a molecule of 205 kDa. These EC membrane components recognized by AECA-IgA may be of importance in the pathogenesis of IgA nephropathy.

Autoantibodies↗
PubMed1992

[Determination of blood hormone levels in patients with "spleen deficiency" syndrome after major operations].

UNLABELLED: The character of "Spleen Deficiency" (SD) Syndrome was evaluated by determination of the blood levels of various gastroenteropancreatic hormones and thyroid hormone. Patients of SD group were diagnosed clinically by Syndrome Differentiation, and those of the normal group were volunteer blood donors. RIA was used to determine all the hormones except T3RUR. RESULTS: TT3, FT3 of the SD group were very significantly lower than that of normal group (P less than 0.001). The levels of rT3 in SD group were significantly higher than normal control (P less than 0.05). For TT4, T3RUR and FT4, there were no significant differences between the two groups. Among the gastroenteropancreatic hormones, gastrin in the SD group was significantly lower than that of the normal group (P less than 0.01), motilin was very significantly higher (P less than 0.002). The value of pp was similar in the two groups, under physiological conditions, however, in adults the hormone tended to increase with age. Since the average age of patients in the SD group was 54.9, and that of the normal group was 38.5, remarkably lower values were seen in the SD group. Other hormones such as VIP, SST, glucagon and insulin were of no significant difference between the two groups. The result showed that thyroid hormone and some of gastroenteric hormones in the blood of patients with SD after major operations were quite different from normal, and was common to patients with general SD Syndrome, with low T3 syndrome.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1990

Relation between plasma atrial natriuretic peptide (ANP) and glomerular ANP receptors in 5/6 nephrectomized rats.

Chronic renal failure (CRF) was induced in male wistar rats (Group I) by 5/6 nephrectomy and the sham-operated ones served as control (Group II). The results showed that in Group I, plasma atrial natriuretic peptide (ANP) levels increased progressively as the Scr was elevated. Plasma R-A rose simultaneously compared to the normal (P less than 0.001). At the 20th week after operation, urine volume and Na decreased significantly (P less than 0.05). The number of glomerular receptors decreased markedly at the 12th week (P less than 0.05) and 20th week (P less than 0.01). Our data suggest that in 5/6 nephrectomized rats, the elevation of plasma ANP level might be partly caused by the damage of glomerular ANP receptors, and the elevated plasma ANP could not play its role in diuresis, natriuresis, blood pressure depression and R-A inhibition as a result of the damage of kidney ANP receptors.

Animals↗
PubMed1989

Pathogenetic role of anti-vascular endothelial cell antibodies in systemic lupus erythematosus.

In order to study the relationship between vascular endothelial cell (VEC) antigen system and systemic lupus erythematosus (SLE), including lupus nephritis, Terasaki's microcytotoxicity test and indirect immunofluorescence were used to detect anti-VEC antibody. VEC was identified by electron microscopy. Sera of 21 SLE patients and of 100 healthy donors were examined. Among the 21 SLE patients evaluated, 17 had kidney injury and 13 were in active stage SLE. Results showed that anti-VEC antibody was found in 76.2% of 21 SLE patients, while only 1% of the controls were positive (P less than 0.05). This antibody was detected in 84.6% of patients in active stage SLE and in 62.5% of patients in inactive stage (P greater than 0.05). In patients with and without kidney injury, it was detected in 82.4% and 50%, respectively (P greater than 0.05). These data show that anti-VEC antibody does exist in the sera of SLE patients, the presence of which is closely related to SLE onset and is independent of whether the patient is in active stage of SLE or has kidney injury. In summary, our data suggest that anti-VEC antibody may be one of the triggering factors in the vasculitis of SLE. It is proposed that renal VEC may act as a target cell which can be attacked by anti-VEC antibody to constitute an in-situ immune complex formation in the kidney, leading to lupus nephritis.

Adolescent↗
PubMed1988

[Immunofluorescent localization of associated antigen of anti-human nasopharyngeal carcinoma cell monoclonal antibody].

The immunofluorescent localization of associated antigen of anti-human nasopharyngeal carcinoma (NPC) cell monoclonal antibody (McAb) was performed in different tissues (NPC, non-NPC tumor, chronic inflammation of nasopharyngeal mucosa, adult normal tissue and embryo tissue) with 5 control experiments. McAb (CN-1, Cs-C1) was produced by Department of Microbiology of our college and all the specimens were confirmed by pathology. The results revealed that Cs-C1 antigen was mainly found on the surface of NPC cells with a positive rate of 80.3%. Majority of the positive cells showed yellow-greenish linear fluorescence surrounding the cell membrane while some cells manifested granular fluorescence. In addition, Cs-C1 antigen was also found in a few embryo tissues, epithelial cells of the normal gastric mucosa and cells of the gastric cancer. It is suggested that Cs-C1 antigen be a kind of molecular structure, being gradually produced or increased in quantity during carcinogenesis, and belong to the tumor associated antigen. Cs-C1 antigen could be important in the study of carcinogenic mechanism of NPC cells and valuable to clinical immunodiagnosis.

Antibodies, Monoclonal↗
PubMed1987

[Precancerous lesion and carcinogenesis of stomach cancer].

A research on pathogenesis of gastric carcinoma was carried out by observing microcarcinoma, small carcinoma, early multicarcinoma as well as the mucosa around the cancer. The results show that the site of different types of carcinoma is correlated to the type of gastric dysplasia. In this paper, various types of gastric dysplasia and multicentric histogenesis of gastric cancer are discussed.

Adenocarcinoma↗
PubMed1986

The antigenic analysis of haemorrhagic fever with renal syndrome viruses in China by monoclonal antibodies.

Thirty-six strains of haemorrhagic fever with renal syndrome (HFRS) virus were isolated from patients and a number of host animals in various areas in China. They were analysed by an immunofluorescence test (IFAT) using 10 monoclonal antibodies (McAbs) specific for the HFRS virus; antigenic differences among the strains have been demonstrated. The HFRS virus strains revealed nine different reactions with the McAbs, showing that there are at least nine different antigenic determinants including group-, type- and strain-specific. Analysis of the results shows that antigenic differences among the HFRS virus strains are mainly related to differences in the host animals.

Antibodies, Monoclonal↗