Biomedical subjects

H Y Jiang

Publications and source records attributed to H Y Jiang.

33 records · Page 2Linked to original sources

PubMed1994

Frequent loss of heterozygosity on chromosome 9 in adenocarcinoma and squamous cell carcinoma of the esophagus.

Loss of heterozygosity (LOH) affecting chromosome 9p has been shown to occur frequently in head and neck cancer, glioma, mesothelioma, melanoma, lung cancer, and numerous other tumor types. Chromosome 9p is therefore presumed to contain a tumor suppressor gene or genes. Since esophageal cancer shares characteristics with some of the above tumor types, we performed a detailed examination of 60 patients with squamous cell carcinoma or adenocarcinoma of the esophagus for LOH at loci D9S162, IFNA, D9S171, D9S126, D9S104, D9S165, and D9S163. Multiplex polymerase chain reactions were performed with the inclusion of one radiolabeled nucleotide, and products were electrophoresed on denaturing polyacrylamide gels. Thirty-six of the 60 patients (60%) exhibited LOH at one or more loci on chromosome 9p. Eight of 17 patients (47%) with adenocarcinoma manifested LOH, while 28 of 43 (65%) with squamous cell carcinoma showed LOH. LOH was most frequent at loci D9S171 (19 of 23, or 83%) and D9S165 (24 of 32, or 75%). These data support the hypothesis that a tumor suppressor gene or genes located on this portion of chromosome 9p exert(s) an effect on esophageal cancer development.

Adenocarcinoma↗

PubMed1994

Microsatellite instability in ulcerative colitis-associated colorectal dysplasias and cancers.

Microsatellites are short nucleotide repeat sequences present throughout the human genome. Alterations of microsatellites, comprising extra or missing copies of these sequences, have been termed microsatellite instability. This abnormality occurs in sporadic and hereditary adenocarcinomas of the proximal colon, as well as in many other tumor types. We determined whether microsatellite instability occurred in ulcerative colitis-associated cancers or precancerous dysplasias. Sixty-three patients were evaluated, consisting of 188 samples of genomic DNA (63 normal controls, 68 cancers, 52 dysplasias, and 5 adjacent tissues) at loci D2S119, D2S123, D2S147, D10S197, and D11S904. Multiplex polymerase chain reaction was performed using one radiolabeled nucleotide, and the products were electrophoresed on denaturing polyacrylamide gels. Seventeen of the 63 patients (27%) possessed lesions showing instability at 1 or more loci. Fourteen of 68 tumor samples (21%) and ten of 52 dysplasias (19%) displayed instability. There was no tendency for a greater number of loci to manifest instability in more advanced lesions. Neither anatomic location nor loss of heterozygosity at the p53 locus were associated with microsatellite instability by 2-way table analysis. These data support a role for defective DNA repair in the generation of a subset of both early and advanced ulcerative colitis-associated colorectal neoplastic lesions.

Colitis, Ulcerative↗

PubMed1994

The MTS1 gene is frequently mutated in primary human esophageal tumors.

Homozygous and heterozygous deletions involving chromosome 9p21 have been reported in a variety of primary human tumors in vivo, and point mutations have been reported in melanoma cell lines in vitro within a probable tumor suppressor gene, MTS1, located at chromosome 9p21. We describe six sequence alterations occurring among twenty-four primary esophageal squamous carcinomas and nineteen primary esophageal adenocarcinomas analyzed by DNA sequencing of MTS1 exon 2. Nucleotide substitutions were observed in five squamous cell carcinomas and in one adenocarcinoma. Two occurred in the germline, while four were somatic alterations. All six nucleotide changes resulted in marked alterations in amino acid sequence. Four were nonsense mutations leading to premature termination codons; nucleotide substitutions identical to two of these stop codons were previously reported in other tumor types. Loss of heterozygosity occurred in all five informative (constitutionally heterozygous) cases in which a sequence alteration was present. Esophageal cancer is one primary human tumor in which MTS1 constitutes an apparent target of heterozygous or homozygous deletions occurring at chromosome 9p21.

Base Sequence↗

PubMed1994

Studies on mechanisms and blockade of carcinogenic action of female sex hormones.

Tumours of mice are induced by administration of Inj. Hydroxyprogesteroni Caproatis Co. (EP) in a practical subthreshold dose of carcinogenesis or 2.5-5 times the human contraceptive dose (simply referred to as 2.5- to 5-fold dose) combined with whole-body 0.5 Gy gamma-ray irradiation. Malignant transformation of Syrian golden hamster embryo (SHE) cells is also induced by 5-fold dose of EP combined with 0.3 Gy gamma-ray irradiation in vitro, thereby indicating that synergistic carcinogenesis can be obtained by combined use of physical and chemical carcinogens. The mechanisms of synergistic carcinogenesis have been further explained by cytogenetics, damage extent of the target cell DNA and production of free radicals. The Chinese traditional medicine with antioxidating effect (Sulekang Capsule, SC), food additive--butylated hydroxyanisole (BHA) and green tea can effectively inhibit the carcinogenic effect of EP or EP combined with gamma rays in mice. They all have marked ability to scavenge or remove the free radicals and thereby reduce the DNA damage.

17 alpha-Hydroxyprogesterone Caproate↗

PubMed1993

Homotransplantation of testis. A report of 11 cases.

Testis homotransplantation has been carried out in 11 patients since 1986. Of them, 8 suffered from congenital testicular dysplasia and the other 3 from orchiatrophy as a result of orchitis. Preoperatively, manifestations were a small penis, small testes, sexual dysfunction, indistinct secondary sex characteristics and low serum testosterone (1.7-7.35 mmol/L). Three cases had cadaver transplants and 8 had living relatives' transplants. The patients were followed up for 7 months to 4 years. The secondary sex characteristics and sexual function were improved remarkably after transplantation. Serum testosterone increased up to 12.8-18.2 mmol/L. All of 5 married patients resumed sexual intercourse satisfactorily. Three others got married after transplantation and have enjoyed normal sexual functions. Spermatozoa have been found in the semen in 3 of the cases.

Adult↗

PubMed1992

Inhibitory effect of cyclosporin A on T lymphocyte DNA synthesis.

The interference of Cyclosporin A (CyA) with peripheral lymphocytes DNA synthesis was investigated. The results showed that the drug could strongly inhibit T cell proliferation in response to PHA stimulation if added at the start or at the early phase of the process, and it failed to do so if added 48 h later when most cells had already started to proliferate. Without PHA, no obvious differences were detected between normal control and CyA-treated cells. A comparison was made between T cell DNA synthesis of peripheral blood lymphocytes of healthy volunteers and renal transplant patients. It was found that T-cell DNA synthesis of patients was significantly lower than that of the healthy controls. From the above it may be suggested that CyA activity on T cell proliferation is similar in vivo and in vitro.

Cell Cycle↗

PubMed1991

[Osteitis pubis as a similarity with prostatitis].

Twenty-eight male patients with osteitis pubis are reported. The clinical symptoms of this disease are very similar to those of chronic prostatitis. The authors think that if the patients with symptoms of prostatitis (prostatodynia) and the clinical data don't support the diagnosis of chronic prostatitis, the osteitis pubis should be considered. The patients with osteitis pubis often has tenderness over the pubic symphysis, and a plain film of the pubis should make the correct diagnosis.

Adult↗

PubMed1990

The effects of long-term using once-a-month injectable contraceptive norethisterone enanthate/estradiol valerate on coagulation in the Chinese.

Sixty-four Chinese women were studied for the effects of injecting once-a-month contraceptive norethisterone enanthate/estradiol valerate between 2 to 4 1/2 years on certain coagulation and fibrinolytic parameters, and 59 women not receiving any steroidal contraception were controls. In both groups there was no significant change in PT, fibrinogen, factor X activity, AT III antigen, AT III activity and fibrinolytic activity expressed by euglobulin lysis time. There was no significant difference in mean levels of factor VIIIR:Ag between the two groups, although a sub-group women in treatment group had higher than accepted levels of factor VIIIR:Ag.

Adult↗

PubMed1990

Hemostatic changes in women using a monthly injectable contraceptive for one year.

The effect of consecutively injecting a one-a-month contraceptive (norethisterone enantate 50 mg with estradiol valerate 5 mg) for one year on haematological parameters was evaluated in 42 Chinese women. The healthy volunteers were randomly allocated to either the treatment group (22) or a control group (20). Blood samples were collected in the follicular and luteal phases of a pretreatment cycle, on days 28 +/- 3 after the 1st, 3rd, 6th, 12th injections and in the luteal phase of the post-treatment cycle. The results showed that in both groups, prothrombin time and fibrinogen fluctuated significantly, and leucocyte count was not significantly changed during the whole course. Factor VIII-related antigen and antithrombin III (AT-III) antigen showed minor changes, although in the 3rd treatment cycle, the differences between the two groups in both parameters reached statistical significance. A progressive and significant decrease in Factor X and AT-III functional activity occurred with the monthly injectable treatment, decreasing by about 14% and 20%, respectively, after 12 months of treatment. Haemoglobin levels were increased in the treatment group after the 3rd injection and remained at the higher level during the study period. It is doubtful whether these changes are likely to be of clinical relevance.

Adult↗

PubMed1990

Experimental studies on the late effects of female sex hormones.

Inj. Hydroxyprogesterone Co. (EP) was injected i.m. into female Wistar rats, different strains of mice of both sex and Syrian golden hamsters with doses of 5-100 times the human contraceptive dose once or twice a month for 10-32 times. In some experiments EP was combined with whole-body 3 Gy gamma ray radiation once or twice. Results show that EP has obvious carcinogenicity and can enhance the gamma ray carcinogenicity, thereby increasing the tumor incidence or the ratio of malignant to benign tumours. Carcinogenic mechanisms of EP have also been studied.

17 alpha-Hydroxyprogesterone Caproate↗

PubMed1990