Biomedical subjects

Y F Shi

Publications and source records attributed to Y F Shi.

At least 55 records · Page 3Linked to original sources

PubMed1992

[Application of serum somatomedin C level to assess the disease activity in patients with acromegaly].

Serum SMC level was measured in acromegalic patients with different disease activity. The serum SMC level of 10 untreated and 15 treated patients with active disease was 30.5 +/- 17.6 and 23.8 +/- 16.3 KU/L respectively. These levels were significantly higher than the value 2.7 +/- 2.8 KU/L in 7 patients during remitting state. The serum SMC level correlated with the basal and the nadir GH level and the area under the GH curve in glucose suppression test. The serum SMC levels in 6 patients with prolactinoma, 10 patients with Grave's disease and 8 patients with renal failure were all in normal range, but in 10 patients with liver cirrhosis it was 0.36 +/- 0.39 KU/L, which was significantly lower than the normal value. We concluded that serum SMC level is a good criterion for assessment of disease activity of acromegaly for it does not require a dynamic test and it does not increase in other diseases.

Acromegaly↗

PubMed1992

Prevalence of growth hormone deficiency of children in Beijing.

103,753 (male 51,994, female 51,759) primary and middle school students aged 6-15 years in two districts in Beijing city were surveyed from October 1987 to April 1989. The heights of the students were measured. According to the height standard of northern cities in China, 202 students with heights below the 3rd percentile for age were requested for detailed history, physical examination, screening GH test bone age, T4, SGPT, chest X-ray, routine urine test and sex chromatin (in female). If GH less than 10 micrograms/L, two provocative tests (L-dopa or clonidine and insulin hypoglycaemia test) were done. Then the heights of the short students were observed for 1/2-2 years. GHD was diagnosed in 12 cases based on the GH peak levels less than 10 micrograms/L in two provocative tests, whose growth velocity was slower than that for students of the same age and sex. Of these subjects with GHD, total GHD (GH less than 5 micrograms/L) was present in 7 and partial GHD (GH = 5-9.9 micrograms/L) in 5. The 12 GHD students (male 9, female 3) aged 8.9-15.7 years accounted for 1/8,646 in the total surveyed students. The male and female GHD accounted for 1/5,777 and 1/17,253 in the total males and females respectively.

Adolescent↗

PubMed1992

Tumors of the heart. An analysis of 79 cases.

There were 79 cases of cardiac tumors seen from 1957 to July 1988. 49 (62.0%) of them were benign and 30 (38.0%) malignant. All the 49 benign tumors except 2 were surgically excised and found to be myxoma. Of them, 18 patients were male and 31 female. 85.7% of the tumors were located in the left atrium, 12.2% in the right atrium and 2.0% in the left ventricle. Palpitation, dyspnea, chest oppression, fever, episodes of syncope and hemiplegia, cough, diastolic and systolic murmurs at the apical or tricuspid area were the common symptoms and signs. Atrial fibrillation was found only in 2 cases. Echocardiographic findings were diagnostic while ECG and X-ray findings were nonspecific. Four patients died after operation. Of the 30 cases of malignant tumors, 15 were secondary tumors metastasized mainly from the lung or mediastinal malignancies. Of 11 primary tumor cases (7 males and 4 females), 3 were malignant lymphoma, 2 mesothelioma of pericardium, 2 malignant myxoma, 1 angiosarcoma, 1 leiomyosarcoma, 1 fibrosarcoma and 1 rhabdomyosarcoma. Another 4 cases were not studied histopathologically. The clinical manifestations, ECG and X-ray findings of the 11 primary tumors were nonspecific but echocardiography was helpful to the diagnosis. Six patients were operated on and 1 died during hospitalization.

Adolescent↗

PubMed1991

In vivo administration of monoclonal antibodies to the CD3 T cell receptor complex induces cell death (apoptosis) in immature thymocytes.

Some thymocytes, upon activation via the TCR complex in vitro, undergo apoptotic cell death. In this report, we examine the cell death induced in the thymus after administration of anti-CD3 or anti-TCR antibodies. We found that shortly after antibody injection, cortical thymocytes undergo apoptosis as characterized by morphologic changes and DNA fragmentation. Anti-CD3 administration led to depletion of nearly all CD4+CD8+ thymocytes, and approximately 50% of CD4+CD8- thymocytes. This depletion predominantly affected cells bearing low levels of CD3, although some depletion also occurred among cells expressing intermediate and high levels. Administration of an anti-TCR antibody also induced apoptosis, but affected significantly fewer thymocytes than anti-CD3. This effect was probably not due to different binding affinities for the two antibodies, because both antibodies show similar dose response effects in an in vitro model of activation-induced apoptosis. This work demonstrates that findings on activation-induced apoptosis in vitro can be extended to the in vivo situation, and further, that the activation of cortical thymocytes, in situ, results in apoptosis and removal of the activated cells. The possible relationships between this activation-induced cell death in immature thymocytes and the process of negative selection of autoreactive T cells is discussed.

Animals↗

PubMed1991

High rates of ras codon 61 mutation in thyroid tumors in an iodide-deficient area.

Using polymerase chain reaction and sequence-specific oligonucleotide hybridization, the frequency of three ras oncogene mutations (N-ras, Ha-ras, and K-ras) in thyroid tumors (25 adenomas, 16 follicular carcinomas, and 22 papillary carcinomas) was investigated in both iodide-deficient and iodide-sufficient areas. The ras oncogene mutation rate was significantly higher in the iodide-deficient area, being 85 versus 17% in the adenomas, and 50 versus 10% in the follicular carcinomas. No mutations were found in papillary carcinomas. The most common mutation site was Ha-ras codon 61 with Gln----Arg substitution. Two ras mutations at codon 61 (Gln----Lys in N-ras and Gln----Arg in Ha-ras) were found in a microfollicular adenoma specimen from Eastern Hungary. We conclude that dietary iodine may modulate ras oncogene mutations, and that in the iodide-deficient area, ras oncogene activation may play a more important role in the initiation and/or maintenance of follicular tumors. Additional factors are, however, necessary to initiate carcinogenesis.

Adenocarcinoma↗

PubMed1991

Antiserum against homologous atrial natriuretic peptide diminishes the natriuretic response during mineralocorticoid escape in rats.

To elucidate the physiological role of atrial natriuretic peptide (ANP) in plasma during mineralocorticoid escape, we investigated the effects of passive immunization with ANP-specific antiserum on deoxycorticosterone (DOCA)-treated rats. Sodium was retained in excess of intake during the first day after treatment with DOCA, and sodium balance returned to control values by the second day, whereas the excretion of potassium exceeded the intake during all days after DOCA treatment. These changes in electrolyte balance were associated with a significant increase in plasma levels of ANP. Administration of ANP-specific antiserum significantly impaired the return to normal sodium balance as well as the augmented kaliuresis that were observed on the second day after injection of DOCA. No significant effect was observed on either sodium or potassium balance after the injection of normal rabbit serum. These results suggest that plasma ANP plays an important role in mineralocorticoid escape.

Animals↗

PubMed1991

[Prospective study of functional changes in the gallbladder and formation of gallstones induced by long-term treatment of somatostatin analogue SMS201-995 in patients of active acromegaly].

We reports the result about the changes of function of gallbladder in 17 acromegalic patients after treatment with long-acting somatostatin analogue SMS201-995 for 3-36 months by ultrasonogram. The number of cases developed bile sludges, gallstones, chronic and acute cholecystitis was 14, 8, 10 and 1 respectively during therapy. The contractibility of gallbladder after fatty meal was inhibited in all of the patients during the course of therapy. A bolus injection of SMS201-995 with a dosage of 100 micrograms for acromegalic patients resulted in marked suppression of the contractibility of the gallbladder. Our result indicates that the decreased contractibility of the gallbladder leads to the formation of gallstones during the long-term therapy of SMS201-995. Therefore, it is important to follow the gallbladder carefully in the course of the therapy of SMS201-995.

Acromegaly↗

PubMed1990

Activation-induced cell death in T cell hybridomas is due to apoptosis. Morphologic aspects and DNA fragmentation.

Some T cell hybridomas, upon activation via the TCR, rapidly undergo cell death. In this paper, we demonstrate that this activation-induced cell death (AICD) is accompanied by morphologic changes seen at the electron and light microscopy levels. The most striking changes are an extensive condensation of the chromatin and formation of membrane blebs. In addition to the morphologic changes, a significant portion of genomic DNA is broken at an interval of approximately 200 bp, producing a ladder of oligonucleosome-sized fragments after gel electrophoresis. Taken together, these observations indicate that AICD proceeds via apoptosis, or programmed cell death. This is additionally supported by the observation that AICD-associated phenomena are at least partially inhibited by cycloheximide or actinomycin D. Curiously, AICD and its associated DNA fragmentation are completely inhibited by aurintricarboxylic acid, a known nuclease inhibitor. The possible relationship between AICD in vitro, and the negative selection process (wherein selection may proceed via AICD of developing, autoreactive thymocytes) is discussed.

Aurintricarboxylic Acid↗

PubMed1990

Cloning and sequence of the human adrenodoxin reductase gene.

Adrenodoxin reductase (ferrodoxin:NADP+ oxidoreductase, EC 1.18.1.2) is a flavoprotein mediating electron transport to all mitochondrial forms of cytochrome P450. We cloned the human adrenodoxin reductase gene and characterized it by restriction endonuclease mapping and DNA sequencing. The entire gene is approximately 12 kilobases long and consists of 12 exons. The first exon encodes the first 26 of the 32 amino acids of the signal peptide, and the second exon encodes the remainder of signal peptide and the apparent FAD binding site. The remaining 10 exons are clustered in a region of only 4.3 kilobases, separated from the first two exons by a large intron of about 5.6 kilobases. Two forms of human adrenodoxin reductase mRNA, differing by the presence or absence of 18 bases in the middle of the sequence, arise from alternate splicing at the 5' end of exon 7. This alternately spliced region is directly adjacent to the NADPH binding site, which is entirely contained in exon 6. The immediate 5' flanking region lacks TATA and CAAT boxes; however, this region is rich in G + C and contains six copies of the sequence GGGCGGG, resembling promoter sequences of "housekeeping" genes. RNase protection experiments show that transcription is initiated from multiple sites in the 5' flanking region, located about 21-91 base pairs upstream from the AUG translational initiation codon.

Amino Acid Sequence↗

PubMed1990

Clinical and biochemical effects of incremental doses of the long-acting somatostatin analogue SMS 201-995 in ten acromegalic patients.

Ten patients (seven women, three men) with active acromegaly, five previously treated and five newly diagnosed, were included in an open-label prospective trial of 3 daily subcutaneous injections of the long-acting somatostatin analogue SMS 201-995 (Sandostatin) at increasing doses in order to obtain maximum growth hormone (GH) suppression. Four patients had received surgery, radiotherapy or bromocriptine. SMS 201-995 doses were increased in a stepwise fashion from 100 micrograms every 8 h (three times daily) to 200, 300 and finally 500 micrograms three times daily at monthly intervals if mean serum GH values failed to decrease to undetectable levels in over 75% of the samples. The optimal dose was maintained for up to 28 months. Significant clinical improvement of headache, soft tissue swelling, facial features, hyperhidrosis and paraesthesia occurred in all patients. Mean 12-h GH levels were significantly suppressed in four patients and fell to normal values in four. Suppression of GH levels was not achieved in two patients. Comparison of the mean interindividual GH values shows that the optimal efficacious dose is 100 micrograms t.i.d. in 7/10 patients. Somatomedin-C (SM-C) was also significantly reduced to below 50% of pretreatment levels in nine patients in whom it was measured. The subsequent increments of SMS 201-995 up to 500 micrograms three times daily did not produce further clinically relevant GH or SM-C suppression. Pituitary tumour shrinkage occurred in five patients. Thyroid function remained normal. Impaired glucose tolerance occurred in four patients. Side-effects (diarrhoea, abdominal discomfort) were mild and transient. Asymptomatic gallstones occurred in three patients on 1500 micrograms/day and one patient on 600 micrograms/day after 6-12 months treatment. This dose-finding study shows that 100 micrograms three times daily SMS 201-995 is an effective therapy for most of the acromegalic patients we treated.

Acromegaly↗

PubMed1990

Treatment of growth hormone deficient patients with recombinant somatropin for 1 year: results of a Chinese multicentre trial.

Fifty-nine patients with idiopathic growth hormone deficiency were included in a Chinese multicentre trial of recombinant somatropin, 0.5-0.7 IU/kg/week s.c. given in six or seven divided doses. The height velocity increased from 2.8 +/- 1.0 cm/year to 13.1 +/- 2.5 cm/year during 1 year of treatment, and typical catch-up growth was observed. The increase in height SDS for chronological age was significant, but the increase in height SDS for bone age was not statistically significant. No adverse reactions to the treatment were recorded. Recombinant somatropin was shown to be very effective and safe during the first year of therapy in patients with growth hormone deficiency.

Child↗

PubMed1990

[Comparison of the therapeutic results of bromocriptine treatment of prolactin microadenoma and macroadenoma].

26 infertile women with prolactinomas were treated by bromocriptine, 24 of them (92%) became pregnant. All of 11 cases with microadenoma restored fertility, 13 out of 15 patients with macroadenomas became fertile. The total is 32 pregnancies. 4 of 32 pregnancies developed spontaneous abortion or fetal death in uterus. In all the women with microadenomas and 11 cases with macroadenomas there were no symptom of enlargement of pituitary tumor, 2 patients with macroadenomas developed visual field defect or paralysis of left oculomotor nerves. 22 patients continued bromocriptine medication for 4.6 +/- 3.6 months and in 6 patients took bromocriptine until delivery. No congenital malformation were found, the development and intelligence were normal in their children. 4 women with microadenomas restored menses at postpartum without taking bromocriptine. The other patients still suffered amenorrhea and galactorrhea after delivery. 8 patients breast-feed their infants for 17.9 +/- 9.5 (7-33) months, no harmful effect on prolactinomas was found. Our data suggest: (1) The pregnancy rate in women with prolactinomas treated with bromocriptine was 92%. (2) Women with microprolactinomas who became pregnant appear to have a very low risk for developing complications and women with macroprolactinomas should be followed closely throughout pregnancy for pituitary tumors enlargement. (3) Bromocriptine therapy do not increase the risk of spontaneous abortion in women with prolactinoma and congenital anomalies of their offspring during pregnancy.

Adult↗

PubMed1990

[Clinical study of fifty cases of Klinefelter's syndrome].

The authors report the clinical manifestations of 50 cases of Klinefelter's Syndrome proven by chromosome studies. The number of cases with the genotype of 47 XXY, 46 XY/47 XXY, 46 XX/47 XXY and 48 XXXY were 42, 6, 1 and 1 respectively. The chief complaint of 68% of the patients was maldevelopment of sex and that of 26% was gynecomastia. One fourth of the patients was born when their mothers' age already exceeded 35. About 1/5 had low intelligence. Secondary sexual characteristics were absent in all the patients. About 2/5 had gynecomastia. The average testicular volume was 4.0-1.3 ml, but no sperm was found in their semen. Their serum testosterone concentration decreased to 5.4 +/- 5.3 mM/L, but the serum TeBG, FSH and LH levels were significantly increased to 66.8 +/- 22.0 nM/L, 24.7 +/- 7.1 IU/L and 12.3 +/- 7.3 IU/L.

Adolescent↗

PubMed1990

Clinical trial with somatonorm in idiopathic growth hormone deficiency in children.

This article reports the efficacy and safety of treatment with Somatonorm in 9 children with idiopathic growth hormone (GH) deficiency in China. The growth velocity increased from 2.6 +/- 0.2 cm/year before treatment to 10.7 +/- 0.5 cm/year at the end of 1-year treatment. The increment of human growth hormone (hGH) level and area under the response curve above the baseline level were larger after one injection of Somatonorm at the dose of 0.1 IU/kg sc than that of 0.17 IU/kg im. Increments of delayed bone age were not significant. There was no correlation between the increase of height growth velocities and the serum Somatomedin-C (SMC) levels during hGH therapy (r = -0.055). Blood sugar levels and blood alkaline phosphatase concentrations increased significantly after therapy. There were no significant side effects. Serum T4 levels of 3 patients dropped below normal after treatment. Serum anti-hGH antibody appeared at 3-12 month in 2 patients, but it did not attenuate the growth velocity.

Child↗

PubMed1990

Effect of acute water loading on plasma levels of antidiuretic hormone AVP aldosterone, ANP fractional excretion of sodium and plasma and urine osmolalities in myxedema.

We monitored the plasma and urine osmolalities, fractional excretion of sodium, fractional excretion of chloride, plasma levels of antidiuretic hormone (ADH, AVP), aldosterone and atrial natriuretic peptide (ANP) before and after acute water ingestion in 12 patients with overt hypothyroidism. The ability of the patients to dilute and concentrate urine was found impaired and the ability of excretion of water load decreased and delayed. Acute water load test was proved to be effective in evaluating the urinary excreting function for the patients. We hypothesize that inappropriate secretion of anti-diuretic hormone and elevated plasma ANP may be homeostatic factors for abnormal urinary excretion in patients with hypothyroidism.

Adolescent↗

PubMed1990

[Studies on the abnormal response of pituitary somatotropin to dopaminergic drugs in patients with acromegaly].

This article studies the effects of dopaminergic drugs on the pituitary GH secreting adenoma. The secretion of GH was enhanced and suppressed in 6 normal adults and 5 acromegalic patients respectively after intravenous infusion of dopamine and oral ingestion of L-dopa. Simultaneous administration of L-dopa and carbidopa (a drug that inhibits the conversion of L-dopa to dopamine in peripheral tissue) showed no suppressive or stimulatory effect on the secretion of GH in acromegaly. This result indicates that an abnormality in the GH secreting cell may be the cause of the different responses of GH to dopaminergic drugs in acromegaly.

Acromegaly↗

PubMed1990

[Evaluation of adult idiopathic growth hormone deficiency with other pituitary hormones deficiency].

The type and percentage of multiple pituitary hormone deficiency (MPHD) were studied in 42 patients with idiopathic growth hormone deficiency (IGHD). It was found that the development of secondary sexual characteristics was poor or absent in 39 patients (93%) with gonadotropin deficiency (GnD). Mean serum testosterone (T), luteinizing hormone (LH) and follicle-stimulating hormone (FSH) levels in the 39 patients were significantly less than those of normal adult males (P less than 0.01). Mean testicular volume in 36 patients with GnD was significantly less than that in 3 with normal T level. We also found that 24-hour urinary free cortisol level (24 hour UFC) was low in 24 (57.1%) of 42 patients, but it is important that none had obvious symptoms of hypoadrenocorticism such as hypoglycemia, hypotension etc and received adrenal-corticosteroid treatment. 22 (52.4%) of the 42 patients suffered from hypothyroidism, with serum thyroxine (T4) level lower than normal but thyrotrophin (TSH) within normal range. 6 patients with hypothyroidism had moderate symptoms such as cold intolerance, constipation, rough and dry skin, slowing down both mentally and physically. 17 patients have treated with thyroxine. From the results mentioned above, 14 of the 41 patients with MPHD had pan-pituitary hormones (LH, FSH, TSH, ACTH) deficiency, only one had isolated growth hormone deficiency. Among all the patients, 23 underwent breech delivery and 11 patients had birth asphyxia. We therefore conclude that: (1) most of the IGHD cases are complicated with other pituitary hormone deficiency; (2) most of the IGHD cases have with MPHD; (3) Breech delivery and birth asphyxia were important etiological factors of IGHD.

Adrenocorticotropic Hormone↗

PubMed1990

[Effect of rifampin on the metabolism of glucocorticoids in Addison's disease].

To investigate the effect of rifampicin on the metabolism of hydrocortisone, we measured serum sodium level and blood glucose concentration before lunch in a patient with Addison's disease when treated with hydrocortisone 30 mg/day alone and together with rifampicin 450 mg/day for more than two weeks. We also studied the area under the plasma cortisol curve (AUC), half-life (T 1/2) and clearance rate (CLs) of hydrocortisone after both oral ingestion and intravenous injection of 20 mg hydrocortisone. The results showed that rifampicin increased the metabolism of cortisol by shortening of its T 1/2, increasing its CLs and decreasing its AUC. It decreases the blood sodium level and glucose concentration and makes the patient liable to have hypoglycemic symptoms before lunch. We conclude that the increase of metabolism of cortisol after simultaneous taking of rifampicin may induce adrenal crisis in Addison's disease.

Addison Disease↗