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Biomedical subjects

Z Jiang

Publications and source records attributed to Z Jiang.

At least 145 records · Page 8Linked to original sources
PubMed1999

Development of L-type calcium channels and a nifedipine-sensitive motor activity in the postnatal mouse spinal cord.

Intrinsic membrane properties are important in the regulation of motoneuronal output during such behaviours as locomotion. A conductance through L-type calcium channels has been implicated as an essential component in the transduction of motoneuronal input to output during locomotion. Given the developmental changes in calcium currents occurring postnatally in some neurons, and the increasing interest in the study of spinal locomotor output in neonatal preparations, experiments were conducted to investigate the postnatal development of L-type calcium channels in mouse motoneurons. This was assessed both physiologically, using a chemically induced rhythmic motor output, and anatomically, using immunohistochemical methods. The electrophysiological data were obtained during rhythmic bursting produced by application of N-methyl-D-aspartate (NMDA) and strychnine to the isolated spinal cord at various postnatal ages. The L-type calcium channel blocker nifedipine has no effect on this ventral root bursting in postnatal day (P) P2-P5 animals, but reversibly reduced the amplitude and/or burst duration of this activity in animals greater than P7. The immunohistochemical evidence demonstrates a dramatic change in the cellular profile of both the alpha1C and alpha1D subunits of L-type calcium channels during postnatal development; the labelling of both subunits increases with age, approximating the adult pattern by P18. These results demonstrate that in the spinal cord, the L-type calcium channel profile develops both physiologically and anatomically in the early postnatal period. This development parallels the development of the mature functional behaviours of weight bearing and walking, and may be necessary for the production of complex motor behaviour in the mature mammal.

Age Factors↗
PubMed1999

Fimbria-mediated enhanced attachment of nontypeable Haemophilus influenzae to respiratory syncytial virus-infected respiratory epithelial cells.

Respiratory syncytial virus (RSV) infection is known to predispose children to otitis media and sinusitis due to bacteria such as nontypeable Haemophilus influenzae (NTHI). In this study, we investigated the role of NTHI surface outer membrane protein P5-homologous fimbriae (P5-fimbriae) in attachment to RSV-exposed A549 epithelial cells. Analysis by fluorescence flow cytometry showed that a live P5-fimbriated NTHI strain (NTHIF+) attached to a higher proportion of RSV-exposed A549 cells than to control cells (mean, 68% for RSV versus 29% for control; P = 0.008), while attachment of the P5-fimbriae-deficient isogenic mutant strain (NTHIF-) was significantly lower than in control cells and rose only slightly following RSV exposure (mean, 17% for RSV versus 10% for control, P = 0.229). Attachment of NTHIF+ did not correlate with the amount of RSV antigen expressed by A549 cells. Furthermore, paraformaldehyde-fixed NTHIF+ also demonstrated an enhanced binding to RSV-exposed cells. Observations by transmission electronic microscopy showed that the mean number of bacteria attached per 100 RSV-exposed A549 cells was higher for NTHIF+ than NTHIF- (99 versus 18; P < 0.001). No intracellular bacteria were identified. UV-irradiated conditioned supernatants collected from RSV-infected A549 cultures (UV-cRSV) also enhanced the attachment of NTHIF+ to A549, suggesting the presence of a preformed soluble mediator(s) in UV-cRSV that enhances the expression of receptors for P5-fimbriae on A549 cells. In summary, RSV infection significantly enhances NTHI attachment to respiratory epithelial cells. P5-fimbria is the critical appendage of NTHI that participates in this attachment. In clinical settings, blocking of the P5-fimbria-mediated attachment of NTHIF+ by passive or active immunity may reduce the morbidity due to NTHI during RSV infection.

Antigens, Viral↗
PubMed1999

Mouse mammary tumor virus carrying a bacterial supF gene has wild-type pathogenicity and enables rapid isolation of proviral integration sites.

Mouse mammary tumor virus (MMTV) has frequently been used as an insertional mutagen to identify provirally activated mammary proto-oncogenes. To expedite and facilitate the process of cloning MMTV insertion sites, we have introduced a bacterial supF suppressor tRNA gene into the long terminal repeat (LTR) of MMTV, thus allowing selection of clones containing it in lambda vectors bearing amber mutations. The presence of supF in the LTR should circumvent the screening process for proviral insertion sites, since only those lambda clones with supF-containing proviral-cellular junction fragments should be able to form plaques on a lawn of wild-type Escherichia coli (i.e., lacking supF). The resulting virus (MMTVsupF) induced mammary tumors at the expected rate in infected mice, deleted the appropriate T-cell population by virtue of its superantigen gene, and stably retained the supF gene after passage via the milk to female offspring. To test the selective function of the system, size-selected DNA containing two proviral-cellular junction fragments from an MMTV supF-induced mammary tumor was ligated into lambdagtWES.lambdaB, packaged, and plated on a supF-deficient bacterial host for selection of supF-containing clones. All plaques tested contained the desired cloned fragments, thus demonstrating the utility of this modified provirus for the rapid cloning of MMTV insertion sites.

Animals↗
PubMed1999

[A case report of heterosexual transmission of HIV infection between spouses with persistent condom use].

OBJECTIVE: To report a case of heterosexual transmission of HIV infection between spouses with consistent condom use. METHODS: The first case with HIV infection was detected in the contracted male workers returned from abroad in Qingdao in 1992 and both he and his spouse were given health education for AIDS/HIV prevention and instructions on condom use. And, his wife was followed-up every six months by detecting her serum anti-HIV. RESULTS: The wife of the index case was negative for anti-HIV in the first 12 blood tests before December 1996. But, she was found suspect of positive for anti-HIV an July 1997 and definitely positive for anti-HIV-1 in August 1997 during her 14th test. In the period of 1992 to 1997, they persisted in condom use during intercourse. Recall of the wife showed that she had low fever in May 1997, suggesting at the window phase of her acute HIV infection. It postulated that she infected with HIV curing March to April 1997. CONCLUSION: The case report indicated that incorrect use of condom could not prevent from HIV transmission between spouses.

Acquired Immunodeficiency Syndrome↗
PubMed1999

Treatment of postapoplectic thalamic spontaneous pain by electroacupuncture at huatuojiaji points.

The authors have treated 30 cases of postapoplectic thalamic spontaneous pain (PTSP) by electro-acupuncture at Huatuojiaji points (Extra), with the other 30 cases of PTSP treated by oral administration of carbamazepine as the controls. The total effective rate was 90% in the acupuncture group, and 86.7% in the control group. The difference in the total effective rate between the two groups was not statistically significant (P > 0.05), suggesting that electroacupuncture at Huatuojiaji (Extra) is a better therapy for PTSP.

Acupuncture Points↗
PubMed1999

[Glutamine dipeptide enriched enteral nutrition improving gut permeability in sever burns].

OBJECTIVE: To determine the effect of glutamine dipeptide on gut permeability in severe burns. METHODS: Twenty-four severe burn patients were randomly divided into two groups: control group and GLN group. All patients received enteral nutrition for 12 days after burn. Both groups were isocaloric and isonitrogen. GLN group patients were given nutrition solution enriched with glutamine dipeptide at a dosage at 0.5 g.kg-1.day-1 (equivalent to L-glutamine 0.3 mg.kg-1.day-1). On the day 1 and 12 after burn, the plasma amino acid was measured by a standard amino acid analyzer. On the day 1, 3, 6 and 12, the gut permeability was detected with Lactulose and Manitol assay by HPLC-PED, and then wound healing rate of burn area was determined on the day 30 and hospital stay was recorded. ANOVA was done for data analysis. RESULTS: The plasma GLN concentrations decreased in both groups on day 1, (control group: 361.3 +/- 70.8 microns/L, GLN group: 348.6 +/- 52.5 microns/L, P = 0.624, normal value: 659.5 +/- 35.0 microns/L), and the GLN group showed high plasma GLN concentration on day 12 (566.4 +/- 128.3 microns/L), with significant difference between control group (417.6 +/- 74.8 microns/L, P = 0.002). On day 1, L/M ratio value was the highest in both groups. On day 3, L/M ratio in the GLN group became lower than that of control group, and returned to normal on day 6 and maintained to day 12. There were significant differences of wound healing rate between the two groups and the length of hospital stay on day 30 (CONTROL GROUP: (81 +/- 7)%, GLN group: (89 +/- 7)%, 0.018) (CONTROL GROUP: 68 +/- 27 days, GLN group: 49 +/- 13 days, P = 0.049). CONCLUSION: The glutamine-dipeptide enriched enteral nutrition can improve the plasma GLN level after severe burn, decrease the gut permeability from early stage, ameliorate wound healing rate on day 30, and reduce hospital stay.

Adolescent↗
PubMed1999

[Clinical study of anastrozole in the treatment of postmenopausal women with advanced breast cancer].

OBJECTIVE: To study the effect and adverse reactions of anastrozole in the treatment of postmenopausal women with advanced breast cancer. METHODS: A multicenter, open, non-randomized and crossover clinical trial on the effect of anastrozole was conducted. Sixty-one postmenopausal women with advanced breast cancer were treated by oral anastrozole, 1 mg once every day. Each patient received 4-6 weeks of treatment. Plasma estradiol concentrations were determined 2 weeks before treatment and within 3 days after treatment discontinued. Effect and adverse reaction were evaluated. RESULTS: The response rate in 60 evaluable cases treated with anastrozole was 21.7% (CR = 0, PR = 13, MR = 2). The effect was correlated with postmenopausal time, previous endocrine therapy and ER status. Plasma level of estradiol was suppressed by 58.3%. The main adverse reactions, including nausea, fatigue, facial flush, were generally tolerable. CONCLUSION: As an aromatase inhibitor capable of decreasing plasma estradiol level, anastrozole is therapeutically effective for advanced breast cancer in postmenopausal women. Side effects are mild and tolerable.

Adult↗
PubMed1999

[Significance of platelet CD62p, CD63 assessment in type 2 diabetes mellitus patients with blood stasis].

OBJECTIVE: To study the relationship between blood stasis and platelet activation and the influential factors on the latter in type 2 diabetes mellitus (DM) patients. METHODS: Platelet CD62p, CD63 expressions were determined in 30 patients of type 2 DM with blood stasis, 27 patients of type 2 DM without blood stasis and 20 normal controls by flow cytometry. RESULTS: CD62p, CD63 levels were significantly higher in type 2 DM with blood stasis group than that without blood stasis group and in normal controls. CD62p was positively correlated with CD63, while positive correlation existed between HbA1c, LDL-C and CD62p in DM patients with blood stasis. CONCLUSION: The increased level of platelet activation was the primary molecular basis in type 2 DM. It was important to perform the Syndrome Differentiation of blood stasis and treatment of activating blood circulation to remove blood stasis in type 2 DM.

Adult↗
PubMed1999

[Clinical study on preventive effect of taozhi zhipu mixture on postoperative intestinal adhesion].

OBJECTIVE: To study the clinical effect of Taozhi Zhipu Mixture (TZM) in preventing postoperative intestinal adhesion. METHODS: Three hundred and ninety-six patients who had received abdominal operation were randomly divided into the treated group (188 cases) and the control group (208 cases). Same treatment was given to both groups excepting that the treated group received TZM orally or by nasogastric tube. The time of borborygmus recovering and first passing of flatus-defecation after operation was recorded. Patient's gastro-intestinal motion was observed by isotope tracing with I131 capsule. The frequency and intensity of borborygmus were measured by a tracer. All patients had been followed up for 2-3 years. RESULTS: The recovery of borborygmus, the first passing of flatus-defecation were much earlier, the I131 capsule passed gastro-intestinal tract more quickly, and tracer showed higher frequency and intensity of borborygmus in the treated group than those in the control group. Follow-up study also showed the treated group was better than the control group in the non-adhesion rate and the total effective rate (P < 0.05). CONCLUSION: TZM has good effect on stimulating postoperational gastro-intestinal peristalsis and preventing the occurrence of postoperational intestinal adhesion.

Adolescent↗
PubMed1999

[Lactulose mannitol ratio in patients after operation].

OBJECTIVE: To study lactulose (lactulose, L) and mannitol (mannitol, M) ratio in urine following operation and investigate the correlation between severity of stress and L/M ratio. METHODS: 20 patients who had received operation were enrolled and each patient was evaluated by APACH II scores. L/M permeability study was performed before the operation and 5 and 10 days after the operation. The L and M concentration was analyzed by HPLC with pulsed electrochemical detection (HPLC-PED). The correlation between L/M ratio and the severity of surgical stress were related. RESULTS: The L/M ratio before the operation was (0.023 +/- 0.002), increased to (0.042 +/- 0.005) in the 5th post-operative day (P < 0.01), and then returned to (0.024 +/- 0.002) (P > 0.05) compared with pre-operation in the 10th Post-operation. A significant correlation between the severity of stress and the L/M ratio was observed (r = 0.762). CONCLUSIONS: The L/M ratio was increased 5 days after the operation and the L/M ratio was correlated with severity of operative stress.

APACHE↗
PubMed1999

[Advances in affinity chromatography].

This review is mainly concerned with the recent advances in (i) mechanism of affinity chromatography; (ii) the use of new techniques such as combinational chemistry, molecular imprinting, de novo design, fusion expression in discovery of ligand; (iii) improvement of support and chromatographic system; (iv) application of affinity chromatography. The review includes 66 references.

Biomimetics↗
PubMed1999

[Excretion ratio of lactulose and mannitol as intestinal permeability index in healthy Chinese volunteers].

OBJECTIVE: To determine lactulose (L)/mannitol (M) excretion ratio with high pressure liquid chromatograph with pulsed electrochemical detection (HPLC-PED) in healthy Chinese volunteers. METHODS: Sixty healthy Chinese volunteers enrolled. For each volunteer the L/M permeability study was performed twice by two different doses, as small dose (1 g mannitol and 2 g lactulose) and regular dose (5 g mannitol and 10 g lactulose). The urine were collected during 6 hours after ingestion of the test solution. The M and L concentrations were analyzed by HPLC with pulsed electrochemical detection. RESULTS: The L/M ratio was 0.026 +/- 0.006 in the small doses tests, and 0.036 +/- 0.008 in the large doses tests. CONCLUSIONS: With HPLC-PED detection, a low doses of lactulose and mannitol can be used to study intestinal permeability. Determination of the L/M ratio may be a way of evaluating intestinal barrier function in clinical practice.

Adult↗
PubMed1999

[Vestibular potentials evoked by electrical stimulation].

OBJECTIVE: To identify the evoked potentials (VsEPs) by electrical stimulation were from vestibule. METHODS: The stimulating electrode was set on the round window of guinea pig. Constant current shocks of 0.05 ms (0.25-1.2 mA) were used to evoke VsEPs by means of vertex-pinna skin electrodes. RESULTS: These potentials were short latencies of (0.973 +/- 0.086) ms, (1.618 +/- 0.176) ms and (2.416 +/- 0.274) ms respectively, which reflected true potentials and were not from electrical stimulus artefacts. It was pure vestibular origin. As being masked with a continuous white noise (120 dB SPL) or removed ipsilateral auditory nerve, and even after facial neurectomy, waves were still existing, but disapeared after selective vestibular neurectomy. The twitching responses in the facial region had never been detected during the whole test. These potentials were bioelectric responses in the vestibular sensory pathway, characterized by threshold saturation, adaptability of excitation, dependent on intact vestibular nerve. CONCLUSIONS: We have set up animal model of recording VsEPs evoked by electrical stimulation on the round window of guinea pigs.

Animals↗
PubMed1999

Alteration in enterocyte gene expression may explain structural and functional changes following glutamine supplemented parenteral nutrition.

Following extensive bowel resection, the intestinal tract undergoes a variety of adaptive responses to enhance bowel function. The purpose of this study was to determine the effect of glutamine-supplemented parenteral nutrition on mucosal cellularity and gut function. In addition, enterocyte gene expression of two relevant systems was also characterized and related to the structural and functional changes that occurred. Male Wistar rats underwent a 60% small bowel resection and jugular vein catheterization and were randomized into two groups. The control group (n = 10) received a standard intravenous nutritional solution and the study group (n = 10) received a similar solution but enriched with alanylglutamine dipeptide. After 7 days blood was taken for amino acid analysis, and bowel was harvested to determine mucosal morphology and expression of mucosal cell glutaminase and IGF-I mRNA. Mesentery lymphnodes were cultured to determine the presence of bacteria and thus access bacteria translocation. Serum glutamine concentration and mucosal architecture were maintained in the study group compared to the controls. Seventy percent of lymphnodes were cultured positive in control vs. only 20% in the study group (P < 0.05). Jejunal mucosal glutaminase and ileum mucosal IGF-I mRNA increased twofold and threefold respectively compared to control animals. Parenteral nutrition supplemented with alanyl-glutamine dipeptide supports mucosal cellularity and regional immune function in rodents following intestinal resection, These alterations are associated with enhanced enterocyte expression of glutaminase and IGF-I. These changes may facilitate the structural and functional alterations which were observed in the glutamine treated animals.

Animals↗