Search PubMed⌕ Search

Biomedical subjects

J Lang

Publications and source records attributed to J Lang.

At least 217 records · Page 12Linked to original sources
PubMed1996

[Management and prognosis of advanced ovarian cancer associated with bowel metastasis and obstruction].

OBJECTIVE: To investigate the high risk factors and prognostic factors of bowel metastasis and obstruction in the patients with late stage ovarian cancer by analyzing the clinical characteristics and to find out appropriate methods to solve this difficult problem. METHODS: 151 cases with ovarian cancer in stages I and IV who received the treatment from January 1, 1988 to December 31, 1992 were analyzed retrospectively. RESULTS: Operative residues, diffuse bowel metastasis, small intestinal involvement and papillary serous cystadenocarcinoma were found to be high risk factors for bowel obstruction. Age, duration between operation and obstruction, level of CA125 at occurrence of obstruction, numbers of operation and the histologic grade were disclosed as prognostic factors. The prognosis was much worse if the score is more than 6. CONCLUSION: Due attention paid to the high risk factors and the prognostic factors should be emphasized to improve the quality of life and the survival rate.

Adolescent↗
PubMed1996

[Diagnosis and management strategies of hereditary ovarian cancer syndrome].

OBJECTIVE: To describe the clinical profile of hereditary ovarian cancer syndrome (HOCS), focusing on the diagnosis and management strategies. METHOD: Eight patients from four families were identified with HOCS. The diagnosis was made by pedigree according to the criteria recommended by Lynch. Clinical manifestations and management strategies were discussed. RESULT: The incidence of epithelial ovarian cancer in HOCS family women was 20% which was higher than that in sporadic ovarian cancer (10%) (P < 0.05). The mean onset age in patients with HOCS was 41.6% years which was younger also than that in sporadic ovarian cancer. Serous cystadenocarcinoma was the predominant histological type of the HOCS, and the prognosis seems to be better. CONCLUSION: Women in families with HOCS are in a population of high risk for epithelial ovarian cancer. Management strategies should include periodical counselling, screening and surveillance. For women with established families, above 40 years of age and identified with HOCS or with histories of breast or colorectal cancer, prophylactic oophorectomy should be considered.

Adult↗
PubMed1995

Direct control of exocytosis by receptor-mediated activation of the heterotrimeric GTPases Gi and G(o) or by the expression of their active G alpha subunits.

The exocytotic release of potent hormones is a tightly controlled process. Its direct regulation without the involvement of second messengers would ensure rapid signal processing. In streptolysin O-permeabilized insulin-secreting cells, a preparation allowing dialysis of cytosolic macromolecules, activation of alpha 2-adrenergic receptors caused pertussis toxin-sensitive inhibition of calcium-induced exocytosis. This inhibition was mimicked very efficiently by the use of specific receptor-mimetic peptides, indicating the involvement of Gi and, to a lesser extent, of G(o). The regulation was exerted beyond the ATP-dependent step of exocytosis. In addition, low nanomolar amounts of pre-activated Gi/G(o) directly inhibited exocytosis. As transient overexpression of constitutively active mutants of G alpha i1, G alpha i2, G alpha i3 and G alpha o2 but not of G alpha o1 reproduced this regulation, the G alpha subunit alone is sufficient to induce inhibition. These results define exocytosis as an effector for heterotrimeric G-proteins and delineate the properties of the transduction pathway.

Adenosine Triphosphate↗
PubMed1995

VAMP-2 and cellubrevin are expressed in pancreatic beta-cells and are essential for Ca(2+)-but not for GTP gamma S-induced insulin secretion.

VAMP proteins are important components of the machinery controlling docking and/or fusion of secretory vesicles with their target membrane. We investigated the expression of VAMP proteins in pancreatic beta-cells and their implication in the exocytosis of insulin. cDNA cloning revealed that VAMP-2 and cellubrevin, but not VAMP-1, are expressed in rat pancreatic islets and that their sequence is identical to that isolated from rat brain. Pancreatic beta-cells contain secretory granules that store and secrete insulin as well as synaptic-like microvesicles carrying gamma-aminobutyric acid. After subcellular fractionation on continuous sucrose gradients, VAMP-2 and cellubrevin were found to be associated with both types of secretory vesicle. The association of VAMP-2 with insulin-containing granules was confirmed by confocal microscopy of primary cultures of rat pancreatic beta-cells. Pretreatment of streptolysin-O permeabilized insulin-secreting cells with tetanus and botulinum B neurotoxins selectively cleaved VAMP-2 and cellubrevin and abolished Ca(2+)-induced insulin release (IC50 approximately 15 nM). By contrast, the pretreatment with tetanus and botulinum B neurotoxins did not prevent GTP gamma S-stimulated insulin secretion. Taken together, our results show that pancreatic beta-cells express VAMP-2 and cellubrevin and that one or both of these proteins selectively control Ca(2+)-mediated insulin secretion.

Animals↗
PubMed1995

Laparoscopic surgical staging of ovarian cancer.

The feasibility of laparoscopic staging in patients with ovarian cancer was undertaken prospectively to determine the ability to adequately evaluate both the intraperitoneal cavity and the retroperitoneal lymph nodes. Two groups of ovarian cancer patients were evaluated: those with optimally debulked advanced disease undergoing second-look procedures and those with presumed stage I disease undergoing surgical staging. Twenty-four of the 44 laparoscopic second-look procedures (56%) were positive for persistent disease. Five of these patients had microscopic disease only, in the omentum, washings, pelvic peritoneum, and in para-aortic lymph nodes (2 patients). In the group of 14 patients undergoing staging for presumed early ovarian carcinoma, metastatic disease was discovered in 8 (57%) patients. Two patients had peritoneal washings positive for adenocarcinoma; 3 had pelvic disease, 1 confined to a fallopian tube and 2 to the pelvic peritoneum; and 3 patients had para-aortic lymph nodes positive for metastatic adenocarcinoma. There were no serious complications in this category. The average hospital stay was 1.6 days. Laparoscopic staging appears to be an accurate staging technique, and further investigation into the validity of this approach is warranted.

Adolescent↗
PubMed1995

Macular sparing as a perimetric artifact.

PURPOSE: We studied the hypothesis that the typical macular sparing of a few degrees was based on an unstable fixation coupled with a nystagmiform searching movement in the direction of the seeing hemiretina. METHODS: By means of microperimetry with a scanning laser ophthalmoscope, we recently tested the visual fields of 15 hemianoptic patients, through direct visual control of the retina. The tests provided us with accurate information about all fixation shifts that occurred. RESULTS: Twelve patients showed macular sparing of 1 to 5 degrees both in the Goldmann visual field and in the scanning laser ophthalmoscope field. Their fixation shifted regularly 1 to 10 degrees toward the seeing hemiretina one to two times per second, then returned rapidly to the foveola. Conversely, three patients showed greater macular sparing, and they all had particular characteristics--extensive fixation shifts, dual fixation, and limited quadrantanopsia. CONCLUSIONS: We believe that macular sparing could be interpreted as a perimetric (not an anatomic) artifact, provided that the results of these tests on 15 patients are confirmed by further similar studies.

Adolescent↗
PubMed1995

[Diagnosis and surgical treatment of bilateral paralysis of the superior oblique muscle].

BACKGROUND: Typically, bilateral superior oblique palsies manifest with small vertical deviation in primary position, reversing in lateral gaze, with a positive headtilt test on both sides, a V pattern, and a chin-down head position. In primary position, excyclotropia often exceeds 10 degrees and markedly increases in inferior gaze. PATIENTS AND METHODS: Retrospective study of 21 patients with bilateral SO palsy who underwent operations including various surgical techniques such as SO tucking, inferior oblique recessions and inferior rectus weakering procedures (recession, posterior fixation). Preoperative symptoms of this group of patients was compared to those of 60 patients with unilateral SO palsy. RESULTS: No significant difference was found between cases operated with complete SO tucking and cases operated with specific surgery on the anterior part of the tendon when pre- and postoperative excyclotropia was compared. Severe excyclotropia in primary gaze, markedly increasing in downgaze, was found to be statistically significantly associated with bilateral lesions (p = 0.001). CONCLUSION: Bilateral SO palsy, even when highly asymetrical, can be surely diagnosed by carefully measuring excyclotorsion in both primary and downgaze by using dissociating devices. To avoid iatrogenic postoperative Brown syndrome it is recommended to adjust the amount of bilateral superior oblique tucking peroperatively, according to the degree of tendon extensibility. In cases of very severe excyclotorsion such a procedure can be completed by mild bilateral simultaneous inferior oblique recessions.

Adolescent↗
PubMed1995

SNAP-25 is expressed in islets of Langerhans and is involved in insulin release.

SNAP-25 is known as a neuron specific molecule involved in the fusion of small synaptic vesicles with the presynaptic plasma membrane. By immunolocalization and Western blot analysis, it is now shown that SNAP-25 is also expressed in pancreatic endocrine cells. Botulinum neurotoxins (BoNT) A and E were used to study the role of SNAP-25 in insulin secretion. These neurotoxins inhibit transmitter release by cleaving SNAP-25 in neurons. Cells from a pancreatic B cell line (HIT) and primary rat islet cells were permeabilized with streptolysin-O to allow toxin entry. SNAP-25 was cleaved by BoNT/A and BoNT/E, resulting in a molecular mass shift of approximately 1 and 3 kD, respectively. Cleavage was accompanied by an inhibition of Ca(++)-stimulated insulin release in both cell types. In HIT cells, a concentration of 30-40 nM BoNT/E gave maximal inhibition of stimulated insulin secretion of approximately 60%, coinciding with essentially complete cleavage of SNAP-25. Half maximal effects in terms of cleavage and inhibition of insulin release were obtained at a concentration of 5-10 nM. The A type toxin showed maximal and half-maximal effects at concentrations of 4 and 2 nM, respectively. In conclusion, the results suggest a role for SNAP-25 in fusion of dense core secretory granules with the plasma membrane in an endocrine cell type- the pancreatic B cell.

Animals↗
PubMed1995

Acute changes in the EEG of workers exposed to mixtures of organic solvents.

In a pilot study, 11 workers were exposed to mixtures of organic solvents during the cleaning of printing rolls. The exposure was considered as low to moderate. The "electroencephalogram (EEG)" was recorded before and after the cleaning. The spectral power was calculated by Fast Fourier Transformation in six frequency bands. After exposure the spectral power in particular increased in the alpha-1 band and in the temporooccipital leads of the delta band in the closed-eye condition.

Adult↗
PubMed1995

[Overexpression of p53 in transitional cell carcinoma of the ovary].

To determine the prevalence of p53 abnormal protein expression in transitional cell carcinoma of the ovary in Peking Union Medical College hospital, and to analyse the correlation between the overexpression of p53 protein and prognostic parameters of transitional cell carcinoma of the ovary, thirty-two transitional cell carcinoma of the ovary and 20 normal ovaries were analysed. Detection of overexpression of p53 protein was carried out by immunohistochemical staining (IHS) using the monoclonal antibody DO-1 on paraffin sections. 41% of 32 samples of transitional cell carcinoma of the ovary showed positive IHS with DO-1, whereas only 5% of 20 normal ovaries showed weakly positive cytoplasmic staining (P < 0.01). p53 overexpression did not correlate with age, CA125 levels, histological grade and lymph node metastasis, but patients with overexpression of p53 had a poor prognosis. Overexpression of p53 is a more common event in transitional cell carcinoma of the ovary. Further studies are warranted to clarify the role of p53 in transitional cell carcinoma of the ovary.

Carcinoma, Transitional Cell↗
PubMed1995

Abdominal scar endometriosis: report of 28 cases.

Twenty-eight cases of abdominal scar endometriosis from January, 1980 to December, 1993 are reported. Of these patients, twenty-four underwent term cesarean section, and four underwent a midtrimester abortion by abdominal hysterotomy. The majority of patients manifested symptoms 1 year after the operation. The most common was a painful mass of scar tissue that became swollen and tender during menstruation. The pathogenesis, diagnosis and treatment are discussed. In correlation with the pathological findings, the effects of drug therapy are evaluated. It was found that surgical excision is the best method of treatment.

Abdominal Muscles↗
PubMed1995

Amplifications of proto-oncogenes in ovarian carcinoma.

Thirty-two cases of ovarian carcinoma, two of normal ovaries, four of benign epithelial ovarian tumor, and three of borderline epithelial ovarian tumor were studied using Southern blot hybridization of DNA. In 15 of the 32 cases of ovarian carcinoma, peripheral lymphocytes were also studied. The amplification rate of C-myc, C-N-ras, C-Ki-ras and C-erbB-2 in ovarian carcinoma were 50%, 44%, 31% and 25% respectively. The amplification of C-Ki-ras and C-N-ras took place chiefly in cases of early stage and those of good differentiation. The amplification of C-N-ras was also found in cases of advanced stage. The amplifications of C-myc and C-erbB-2 were chiefly found in cases above stage III and those of poor differentiation. A total of 83% of the patients who died were found to have amplifications of more than 2 proto-oncogenes, with which the amplification of C-erbB-2 was involved.

Adenocarcinoma, Clear Cell↗