Search PubMed⌕ Search

Biomedical subjects

J Sun

Publications and source records attributed to J Sun.

At least 487 records · Page 27Linked to original sources
PubMed1997

[Separation of pharmaceutical enantiomers on column and thin-layer plate of cellulose triacetate].

Microcrystalline cellulose triacetate (CTA) was prepared by heterogeneous acetylation of microcrystalline cellulose and used as liquid chromatographic chiral stationary phase and chiral thin layer plate to separate pharmaceutical enantiomers. The racemic Troegor's base, mathaqualone, chlormezanone and chloroquine were separated on the CTA chiral column and on the CTA chiral plate. 95% ethanol and the mixtures of 95% ethanol and water with different ratio and different pH values were used as mobile phase. The influences of eluent composition, pH and temperature on the chiral separation were discussed. The experimental results indicate that the CTA chiral plate was more sensitive to eluent composition and pH than chiral column possibly because the chiral adsorbent was not swollen on the plate.

Cellulose↗
PubMed1997

[Cyst of temporomandibular joint with two cases of clinical and pathological analysis]

In this paper,two cases of cyst of temporomandibular joint were reported.We studied eleven cases' literature combined with our clinical and pathological findings,including B typed ultrasonography, CT image and surgical management.We analyzed this kind of cyst from etiological pathological and clinical features and diagnostic therapeutic event.It is a very rare disease with the preferential incidence in woman.We suggested B typed supersonic exam be the first exam method,surgical removal is the best regime.But final diagnosis is depend upon biopsy.

Journal Article↗
PubMed1997

[Detection of hepatitis G virus RNA in sera in non A-E hepatitis patients using polymerase chain reaction with multiple set primers].

A double polymerase chain reaction, involoving nested primers deduced from NS3-5 regions of the hepatitis G virus (GBV-c/HGV) genome, was developed for a sensitive and specific detection of GBV-C (HGV) RNA. With this method, 10 anti-HGV positive patients with non A-E hepatitis and 10 healthy subjects were tested. Among 10 patients, GBV-C RNA was detected in 9, 8, 4, 9 patients by the NS-3 (1) primers, the NS3(2) primers, the NS4 primers, the NS5(1) primers and the NS5(2) primers respectively. Control sera from 10 healthy subjects did not reveal GBV-C (HGV) RNA by any set of the primers. These data suggest that the detection rate of GBV-C (HGV) RNA is different in various set of primers, the NS3(1) and the NS5(2) primers are superior to other primers and are more suitable for RT-PCR of GBV-C (HGV) RNA.

DNA Primers↗
PubMed1997

Simple and reliable methods to assess hepatocyte viability in bioartificial liver support system matrices.

New assays were compared with tritiated thymidine (3HTdR) and trypan blue dye exclusion for evaluating hepatocyte viability on cytodex 3 beads and in microcapsules, the matrices used in bioartificial liver support systems. They were the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) 5 min qualitative assay and the 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4 -sulfophenyl)-2H -tetrazolium, inner salt (MTS) 1 h quantitative assay. Both tetrazolium salts are cleaved in active mitochondria, the reaction occurring, therefore, in living cells only. After bathing at 39 degrees C with MTT for 5 min, porcine or rat hepatocytes on cytodex 3 beads were detached by collagenase while those in microcapsules were released by citrate treatment or passage through a fine needle. Cell viability was determined directly by microscope. The MTT 5 min metabolic inclusion test and MTS 1 h quantitative assay results correlated closely with those obtained by the 3HTdR, trypan blue dye exclusion, and fluorescein diacetate (FDA) methods. Both the new assays are sensitive, accurate, simple, and time-saving.

Animals↗
PubMed1997

beta-Carotene and alpha-tocopherol inhibit the development of atherosclerotic lesions in hypercholesterolemic rabbits.

Male New Zealand White rabbits were made hypercholesterolemic by feeding an atherogenic diet (0.5% cholesterol, 3% peanut oil, and 3% coconut oil) with or without (control) antioxidants for 8 weeks. The antioxidant treatments were intravenous injection of beta-carotene (25 mg/kg/BW, twice weekly), dietary supplementation of alpha-tocopherol (0.5%), and a combination of both. Antioxidant treatments significantly increased plasma and LDL antioxidant levels in the above three groups. Intravenous injection of beta-carotene significantly decreased total and LDL cholesterol concentrations, thoracic atherosclerotic lesion area, and intimal thickness, but had no effects on LDL oxidation ex vivo as compared to control. Added dietary alpha-tocopherol significantly decreased the susceptibility of LDL to oxidation ex vivo, aortic atherosclerotic lesion area and intimal thickness, but had no effects on plasma cholesterol levels as compared to control. Combination of both antioxidants significantly decreased total and LDL cholesterol concentrations, susceptibility of LDL to oxidation ex vivo, as well as atherosclerotic lesion area and intimal thickness at aortic arch and thoracic aorta as compared to control, but not beta-carotene or alpha-tocopherol groups. These data suggest that the antihypercholesterolemic effects of beta-carotene and antioxidant effects of alpha-tocopherol may benefit rabbits fed an atherogenic diet by inhibiting the development of atherosclerotic lesions.

Animals↗
PubMed1997

Evaluation of hydroxyethyl-starch-ferrioxamine as an intravascular MR contrast agent for assessment of myocardial perfusion.

PURPOSE: The present study was carried out to evaluate a new intravascular contrast agent hydroxyethyl-starch-ferrioxamine (HES-FO) for assessment of myocardial perfusion. MATERIAL AND METHODS: Isolated pig hearts were perfused with a crystalloid cardioplegic solution in a Langendorff apparatus. MR images were acquired along the short cardiac axis using T1- and T2*-weighted methods. Gd-DTPA and HES-FO were used as the standard extracellular and test contrast agents, respectively. RESULTS: We found that T1-weighted signal intensity was not significantly affected by HES-FO, but increased significantly in presence of Gd-DTPA. On the other hand, HES-FO resulted in a rapid, transient but significant decrease in T2*-weighted signal intensity. Although Gd-DTPA also decreased T2*-weighted signal intensity considerably, it took much longer for the T2*-weighted signal intensity to return to its initial steady-state with Gd-DTPA than with HES-FO. Moreover, increasing the dose of HES-FO (from 0.0023-0.0138 mmol/kg b.w.) had no effect on the time at which the T2* effect reached its maximum or on the duration of the T2* effect. However, these times and durations were affected significantly by increasing the dose of Gd-DTPA (0.0023-0.027 mmol/kg b.w.). CONCLUSION: The results suggest that HES-FO provides information regarding myocardial vascular flow which cannot be obtained using Gd-DTPA. It is expected that the combined use of intravascular and extracellular type contrast agents will allow more complete assessment of tissue perfusion.

Animals↗
PubMed1997

Existence of an abnormal nitric oxide metabolism seen in glomeruli and inner medullary collecting duct in diabetic rat.

OBJECTIVE: To investigate the nitric oxide (NO)-dependent 3', 5'-cyclic guanosine monophosphate (cGMP) stimulation or inhibition in isolated glomeruli and inner medullary collecting duct (IMCD) cells from normal and diabetic rats for elucidating the probable role of NO in diabetic nephropathy. METHODS: Glomeruli and IMCD cells were obtained from anesthetized diabetic rats, 2 weeks after streptozotocin-induction, and normal rats, and incubated for 10 minutes under basal state or adding different drugs. cGMP was measured by radioimmunoassay. RESULTS: Diabetic glomeruli had a higher generation of cGMP under basal state but failed to further response of L-arginine, which was contrary to the glomeruli from normal rats. NG-monomethyl-L-arginine prevented the elevation of cGMP after L-arginine stimulation in normal rats but not in diabetic rats. Acetylcholine produced a concentration-dependent of cGMP accumulation in the glomeruli of both groups, but the extent was relatively smaller in diabetic than in normal. A similar tendency was also observed in sodium nitroprusside treated glomeruli. However the cGMP increment in response to atrial natriuretic peptide was identical in the two groups. For the IMCD cells, neither the difference of basal cGMP nor those responses related to acetylcholine or sodium nitroprusside could be observed. But the attenuated response to L-arginine also existed in diabetic IMCD cells. CONCLUSION: Both diabetic glomeruli and IMCD cells have an abnormal NO metabolism, which may account in part for the disturbance of renal hemodynamics.

Animals↗
PubMed1997

Multiprimer--PCR for screening of IgH and T-cell receptor rearranged genes in acute lymphoblastic leukemia.

OBJECTIVE: To develop a multiprimer-polymerase chain reaction (multiprimer-PCR) method for detecting immunoglobulin heavy chain (IgH) and T-cell receptor (TCR) rearranged genes in the same amplification. METHODS: Multiprimer-PCR protocol, a mixture of four different primers used in the same reaction detected IgH CDR-III and TCR V gamma I-J gamma Ligenetic rearrangements in 40 acute lymphoblastic leukemia (ALL) patients. RESULTS: Thirteen cases were found to have IgH CDR-III and TCR V gamma I-J gamma genetic rearrangements. Ten cases were found to have TCR V gamma I-J gamma genetic rearrangements. Thirteen cases were found to have IgH CDR-III genetic rearrangements. The amplification result of multiprimer-PCR was the same as separate amplification. The sensitivity of multiprimer-PCR was 10(-4)-10(-5) DNA level, which was the same as separate PCR amplification. All positive cases with IgH rearranged gene were confirmed by Southern blot. CONCLUSION: Multiprimer-PCR could screen two distinct rearranged genes in a single amplification, and is more suitable for screening of specimens collected at diagnosis.

Adolescent↗
PubMed1997

[Sweat gland carcinoma of the vulva, report of 7 cases].

OBJECTIVES: To report the clinical and pathologic features and to evaluate the treatment results of 7 cases of sweat gland carcinoma of the vulva. METHODS: The clinical records of the 7 cases of sweat gland carcinoma of the vulva, admitted to our hospital for treatment between December, 1974 and December, 1994, were reviewed. The data including clinical and pathologic features, treatments and posttreatment follow-ups. Five of the 7 cases were referred from other hospitals, 4 followed by local resection and 1 with recurrence 7 years after surgery. RESULTS: 5/7 of the cases were alive for more than 5 years. One of the 5 cases recurred twice at 7 and 11 years after the initial treatment and each time remedied by radiotherapy, but eventually died of tumor with pulmonary metastasis at the 17th year. Two died within 5 years after treatment; one from cerebral hemorrhage and the other from extensive cancer metastasis 1 year and 9 months after surgery. CONCLUSIONS: The prognosis of sweat gland carcinoma of the vulva is fairly good. Wide local resection of the vulva or radical vulvectomy is the treatment of choice.

Adenocarcinoma↗
PubMed1997

[A clinical analysis of 153 uterine sarcomas].

OBJECTIVE: To evaluate the prognostic factors and treatment methods of 153 uterine sarcomas. METHODS: 153 cases of the uterine sarcoma were eligible for this retrospective study. Of the 153 cases, 48 were leiomyosarcomas, 47 mixed mesodermal sarcomas, 37 endometrial stromal sarcomas, 8 carcinosarcomas, 4 sarcoma botryoides, 1 fibrosarcoma, and 8 malignant lymphomas. 81 cases were in stage I, 11 stage II, 33 stage III and 11 stage IV. 38 cases were treated by surgery alone, 24 by surgery combined with radiation therapy, 50 by surgery plus chemotherapy, 23 by surgery plus radiation therapy and chemotherapy, 4 by radiation therapy alone, 3 by chemotherapy alone, and 11 by radiation therapy plus chemotherapy. RESULTS: The overall 5-year survival rate was 49.0%, and that of leiomyosarcomas, mixed mesodermal sarcomas and endometrial stromal sarcomas was 46.9%, 34.1% and 69.3% respectively (P < 0.01). The 5-year survival rate of lesions limited to the uterus (stage I + II), and that of pelvic cavity invasion (stage III) and distant metastases was 59.6%, 25.6% and 10.0% respectively (P < 0.01. When the uterus was smaller than a 3 months pregnant uterus, the 5-year survival rate was 49.9%. When the uterus size larger than a 3 months pregnant uterus, the survival rate was 18.8% (P < 0.05). Premenopausals surviving 5-year accounted for 56.3% and post-menopausal 28.9% (P < 0.01). CONCLUSIONS: The prognosis of uterine sarcoma is significantly associated with histologic type, clinical and surgico-pathological stage, uterine size and pre- or post-menopausal status. Radiation or chemotherapy alone is palliative. Postsurgical adjuvant radiotherapy significantly decreased vaginal and pelvic recurrences rates. A combination of surgery, radiotherapy and chemotherapy can reduce pelvic recurrence as well as enhance survivals.

Adolescent↗
PubMed1997

[Detecting pathogens of fetal defects in paraffin embedded tissues by polymerase chain reaction].

OBJECTIVE: To examine 3 types of pathogens in dead fetus with congenital defects for exploring the pathogenesis. METHODS: The paraffin embeded brain and liver tissues from 39 fetal autopsies with congenital defects were examined for toxoplasma, cytomegalovirus, and herpes simplex II by polymerase chain reaction. Among them 16 placentae were examined as well. RESULTS: Pathogens were detected in 25 of 39 cases, a positive rate of 64%. Nine out of the 13 fetuses with urogenital defects were positive for the shove pathogens, while 8 from the 12 with neural tube defects were positive as well. CONCLUSION: Intrauterine infection was one of the important causes of birth defects. The characteristics of placenta morphologic changes were described, and the significance of placenta investigation in congenital malformation was emphasized.

Animals↗
PubMed1997

[Carcinoma metastatic to the cervix: a study of 19 cases].

OBJECTIVES: To report the clinical features and to evaluate the treatment results of 19 cases of cervical metastatic carcinoma. METHODS: We analyzed retrospectively the 19 patients with carcinoma metastatic to the cervix treated during the period of 1959 to 1994 at Cancer Hospital, Chinese Academy of Medical Sciences. RESULTS: The average age of patients was 43.7. The main symptom was irregular vaginal discharge and (or) bleeding. In most patients, the primary cancers originated from digestive tract or ovary. The treatment methods included radiotherapy alone, radiotherapy combined with chemotherapy after operation, and surgery plus radiotherapy. The 1-, 2- and 5-years survival rates (life-time table were 68.5%, 47.3% and 26.2% respectively, and the longest period for survived patient with dysgerminoma has lived was more than 22 years. CONCLUSION: The active proper treatment of primary cancer can prolong the survival time of patients with carcinoma metastatic to the cervix. The patients whose metastatic lesions are limited to the cervix and sensitive to the radiation may be cured by radiotherapy and combination therapy.

Adolescent↗
PubMed1997

[Therapeutic modalities of endometrial carcinoma in stage I and II].

OBJECTIVE: To evaluate the effectiveness of different therapeutic modalities of endometrial carcinoma in stage I and stage II. METHODS: From 1984 to 1992, 205 patients with endometrial carcinoma in stage I and stage II were treated in our hospital. The clinical and pathological data were analyzed retrospectively. There were 122 cases in stage I and 83 in stage II. According to therapeutic methods, patients could be divided into 4 groups. Group 1 (surgery group): 81 cases; Group 2 (full dose preoperative intracavitary afterloading irradiation, A point 45G y +/- 10%, F point 50 Gy +/- 10%): 62 cases; Group 3 (non-full dose preoperative intracavitary afterloading irradiation, doses at both point A and point F less than 1/2 of full dose mentioned above): 36 cases; Group 4 (radiotherapy alone): 26 cases. There were no significant differences in pathological type, differential grade, median age and operative methods among the 4 groups. RESULTS: The 5-year survival rate of group 1 to group 4 was 83.1%, 96.5%, 84.8% and 62.5% respectively in stage I, and 82.0%, 90.9%, 51.4% and 62.7% respectively in stage II. The 5-year survival rate was significantly higher in group 2 (P < 0.05). CONCLUSIONS: The results suggested that operation combined with full dose preoperative intracavitary afterloading irradiation provided the best therapeutic effect, whereas non-full dose preoperative intracavitary afterloading irradiation showed none of benefit.

Adenocarcinoma↗
PubMed1997

[Dissociation and culture of primary auditory neurons in postnatal chicken].

In the present study, a primary culture of auditory neurons in 10-16-day old chickens was carried out. We observed the morphologic features of auditory neurons at different culturing stages by using phased-contrast and scanning electron microscope, and particularly described their growth and developmental process. The results indicated that a steady and reliable culturing method established here would contribute to the biological research of inner ear in vitro.

Animals↗
PubMed1997

Early intervention improves intellectual development in asphyxiated newborn infants. Intervention of Asphyxiated Newborn Infants Cooperative Research Group.

OBJECTIVE: To evaluate the effect of early intervention on the intellectual development in asphyxiated newborn infants. METHODS: Full term asphyxiated infants (Apgar score < or = 6 at 5 minutes after birth) were randomly assigned to early intervention group (34 cases) and conventional care (30 cases) group. The normal control group consisted of 38 infants. Sex, mother's educational background, environmental condition and physical development were not significantly different in the 3 groups. Zero to two years early intervention program was compiled on basis of the national and foreign material about 1 month ahead of average development of the child. It included motor, cognitive, speech development and social behavior. Parents were instructed to carry out early intervention. RESULTS: At the age of 1.5 years, average score of mental development index (MDI) in early intervention group was 14.6 higher than that in conventional care group (F = 18.86, P < 0.0001). MDI score in early intervention group caught up with that in normal control group (F = 2.17, P > 0.05). Conventional care group was 9.7 lower than normal control group (F = 10.14, P < 0.01). Two of 30 cases (6.7%) in conventional care group was mentally retarded while none was mentally retarded in the early intervention group. CONCLUSIONS: The results showed that the early intervention could promote intellectual development of asphyxiated infants and be of much benefit to the prevention of mental retardation.

Asphyxia Neonatorum↗
PubMed1997

[Improving the repair of the skull defects in 60 children].

The skull defects with neogenetic bone were repaired with a method in which the neogenetic bone, the cranial periosteum were sutured and fixed to a Ti-net. Totally 60 children were treated. This method has following advantages: 1. Averting trephining of skull to reduce blood loss and the possibility of brain injury: 2. The neogenetic bone is well protected so that it would grow more normally; 3. The method is easy and the operation time is shortened; 4. There is little reaction and postoperative results are satisfactory. The paper describes the principle and technic of the method.

Brain Injuries↗
PubMed1997

[Effects of nicotine on expression of c-fos-like protein in hippocampal formation in mice].

Expression of c-fos-like protein in hippocampal formation of mice, who were trained in a step-down test, was studied with immunohistochemical techniques to study the effects of nicotine on their learning and memory. Results showed that difference of their learning achievements (with number of errors in the test as an indicator) in a five-minute step-down test between trial and control groups did not reach statistical significance, but expression of c-fos-like protein in hippocampal formation in trial mice two hours after administration of nicotine was significantly different from that in controls. Number of positive c-fos cells in hippocampal CA3 and dentate gyrus of the mice treated with 2 mg/kg of nicotine was significantly greater than that in those treated with 1 mg/kg (P < 0.01), and there was no difference in it between those treated with 1 mg/kg of nicotine and controls treated with normal saline. It suggests that 2 mg/kg of nicotine may damage their learning and memory in mice.

Animals↗