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Biomedical subjects

Z Jing

Publications and source records attributed to Z Jing.

At least 19 recordsLinked to original sources
PubMed2004

Genome-wide identification of NBS genes in japonica rice reveals significant expansion of divergent non-TIR NBS-LRR genes.

A complete set of candidate disease resistance ( R) genes encoding nucleotide-binding sites (NBSs) was identified in the genome sequence of japonica rice ( Oryza sativaL. var. Nipponbare). These putative R genes were characterized with respect to structural diversity, phylogenetic relationships and chromosomal distribution, and compared with those in Arabidopsis thaliana. We found 535 NBS-coding sequences, including 480 non-TIR (Toll/IL-1 receptor) NBS-LRR (Leucine Rich Repeat) genes. TIR NBS-LRR genes, which are common in A. thaliana, have not been identified in the rice genome. The number of non-TIR NBS-LRR genes in rice is 8.7 times higher than that in A. thaliana, and they account for about 1% of all of predicted ORFs in the rice genome. Some 76% of the NBS genes were located in 44 gene clusters or in 57 tandem arrays, and 16 apparent gene duplications were detected in these regions. Phylogenetic analyses based both NBS and N-terminal regions classified the genes into about 200 groups, but no deep clades were detected, in contrast to the two distinct clusters found in A. thaliana. The structural and genetic diversity that exists among NBS-LRR proteins in rice is remarkable, and suggests that diversifying selection has played an important role in the evolution of R genes in this agronomically important species. (Supplemental material is available online at http://gattaca.nju.edu.cn.)

Amino Acid Sequence↗
PubMed2004

Modelling periodic oscillation of biological systems with multiple timescale networks.

In this paper, we aim to develop a new methodology to model and design periodic oscillators of biological networks, in particular gene regulatory networks with multiple genes, proteins and time delays, by using multiple timescale networks (MTN). Fast reactions constitute a positive feedback-loop network (PFN), while slow reactions consist of a cyclic feedback-loop network (CFN), in MTN. Multiple timescales are exploited to simplify models according to singular perturbation theory. We show that a MTN has no stable equilibrium but stable periodic orbits when certain conditions are satisfied. Specifically, we first prove the basic properties of MTNs with only one PFN, and then generalise the result to MTNs with multiple PFNs. Finally, we design a biologically plausible gene regulatory network by the cI and Lac genes, to demonstrate the theoretical results. Since there is less restriction on the network structure of a MTN, it can be expected to apply to a wide variety of areas on the modelling, analysing and designing of biological systems.

Biological Clocks↗
PubMed2001

Nocistatin, a peptide reversing acute and chronic morphine tolerance.

It has been reported that intracerebroventricular (i.c.v.) injection of nociception/orphanin FQ (OFQ) can antagonize morphine analgesia, whereas i.c.v. OFQ antibody can reverse morphine tolerance. Nocistatin (NST) is a recently characterized neuropeptide possessing an antagonizing effect on OFQ. Here we examine whether i.c.v. NST would result in a reversal of morphine tolerance. The results showed that: (1) i.c.v. NST at doses of 0.005, 0.05, 0.5, 5 or 50 ng per rat produced a bell-shaped dose-dependent reversal of chronic morphine tolerance, with maximum response at 0.5 ng. (2) Acute morphine tolerance could also be reversed, albeit partially, by i.c.v. NST at 0.5 ng. (3) The reversal of acute and chronic morphine tolerance by NST was completely abolished when NST (0.5 ng) was co-injected with (8 microg) OFQ. Since OFQ and NST are derived from the same preprohormone, the profile of its splicing in the CNS may play an important role in determining the effectiveness of morphine analgesia.

Analgesics, Opioid↗
PubMed2001

An evaluation of the colorimetric assays based on enzymatic reactions used in the measurement of human natural cytotoxicity.

In recent years colorimetric assays based on an enzymatic reaction such as the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay have been used in an attempt to replace the conventional isotopic assay for cell-mediated cytotoxicity. To clarify the problems in the colorimetric assays for natural cytotoxicity, K562 cells were employed as target cells and peripheral mononuclear cells (PBMCs) from cancer patients were used as effector cells. No correlation was found between the 51Cr assay and the MTT assay (P>0.05) or the N-acetyl-beta-D-glycosaminidase (NAG) release assay (P>0.05) in 16 cancer patients. Labeling effector cells showed that the 51Cr release levels of such cells in 19 chemotherapy patients were significantly higher than the levels from target cells in this group (P<0.01) and from effector cells in the control group (P<0.01). There was no correlation between the positive and negative 51Cr assays (P>0.05). The sensitivity of the MTT assay was greatly decreased by washing K562 cells prior to loading MTT solution. Enzyme release occurs as a result of cell metabolism and elevated enzyme release is associated with freezing. These findings indicate that the colorimetric assays based on an enzymatic reaction are not suitable for the detection of natural cytotoxicity in all populations, and are especially not suitable for the assay of natural cytotoxicity in chemotherapy patients.

Chromium Radioisotopes↗
PubMed2001

Public awareness of stuttering in Shanghai, China.

This study reports the results of an investigation of knowledge and public awareness of stuttering among laypersons in Shanghai, China. A total number of 1968 respondents answered a questionnaire including questions about prevalence, onset, gender distribution and occurrence in different cultures, cause, treatment, intelligence and heredity of stuttering. Stuttering appears to be a disorder that most people in the Shanghai area are familiar with, and for several aspects a considerable number of respondents held views that are in line with current knowledge about stuttering. For some aspects though knowledge is limited, indicating a need for disseminating scientific information on stuttering. The results of the present study are compared with a similar Belgium study.

Adult↗
PubMed2001

[Profile of telomerase and telomerase RNA expression in nasopharyngeal carcinogenesis of rats induced by N, N'dinitrosopiperazine (DNP)].

OBJECTIVE: To investigate the profile of telomerase and telomerase RNA expression in nasopharyngeal carcinogenesis (NPC) induced by N, N'dinitrosopiperazine (DNP) and examined histolofically. METHODS: Nasopharyngeal carcinomas of rats were induced by DNP and examined histologically. PCR-ELISA and nested RT-PCR were used to assay telomerase and telomerase RNA expression at different stages in the nasopharyngeal tissues of rats. RESULTS: During the carcinogenesis process, telomerase activity increased along with the formation of a nasopharyngeal carcinoma. Telomerase expression was positively related with nasopharyngeal carcinogenesis. Telomerase RNA expression was present and did not change during the NPC process. Expression of telomease RNA was earlier than telomerase activation. Telomerase activation and telomerase RNA expressin were also detected in the pre-cancerous nasopharyngeal lesions. CONCLUSION: Telomerase activation may participate in the onset and progression of NPC, and is an early step in NPC.

Animals↗
PubMed2001

Studies on the development of DNA vaccine against Cysticercus cellulosae infection and its efficacy.

DNA vaccine against Cysticercus cellulosae infection was developed and its efficacy was tested. A pair of primers specific to antigen B gene of C. cellulosae was designed which amplified the gene successfully with RT-PCR. The gene was ligated to PV93 vector, and the recombinant of antigen B gene and PV93 was transformed to JM83 cells. The transformed JM83 cells were cultured in a large scale and the plasmid purified. Based on the recombinant plasmid. a DNA vaccine was developed and used to vaccinate two groups of experimental pigs. In each group, there was a routine vaccine, an enhanced vaccine and a control group. Groups 1 and 2 were challenged at 4 months and at 14 days post vaccination respectively with eggs of Taenia solium. The antibody response was also tested with ELISA. The results suggested that all animals vaccinated AgB gene DNA vaccine, no matter by routine or enhanced vaccine, their antibodies reached maximum peak 23 days post vaccination and decreased gradually. When the animals were challenged 4 months after vaccination, they had strong immunity and the parasites decrease rates were 91.2% and 93.1% respectively. When pigs vaccinated with AgB gene DNA vaccine were challenged 14 days post vaccination with 18,000 eggs/pig. The animals showed strong immunity and the parasite decrease rates were 99.5% and 84.9% respectively. However at that time, the antibodies did not reach the peak. While in the control group, the number of C. cellulosae was as many as 2,500. It was concluded that the pigs vaccinated with DNA vaccine had strong immunity against infection of eggs of T. solium.

Animals↗
PubMed2000

In vivo gene expression profile analysis of metallothionein in renal cell carcinoma.

The antiapoptotic and mitogenic responses of metallothionein (MT) have been well documented in vitro. While MT protein overexpression, frequently encountered in a number of human primary tumors, has been shown to be correlated with disease progression, little information is available on the in vivo isoform expression of MT. In this study we have demonstrated the occurrence of MT proteins and further defined their differential expression profile in human primary renal cell carcinoma (RCC). Pooled normal human kidney RNA and paired biopsy specimens (tumor and control) obtained from 11 patients diagnosed with RCC with tumor grade ranging from 1-3 and a pathological staging of T2-T3 (N0M0) were used for the study. Samples were analyzed for the presence of MT protein using immunohistochemical (IHC) analysis and for MT isoform-specific mRNA expression by reverse transcriptase polymerase chain reaction. Metallothionein protein assumed both cytoplasmic and nuclear staining in cancer cells and was detected in eight of 11 samples (72%) with polyclonal antibodies. The immunoreactivity of MT protein, but not its cellular localization, in RCC specimens suggests a relationship between and advanced disease. While alterations in the basal level of expression of MT-1E, MT-1F and MT-1X genes remained unchanged, significant up-regulation of MT-2A and down-regulation of MT-1A and MT-1G transcripts was observed in RCC tissue specimens when compared with controls. Intriguingly, the paired RCC biopsy specimens had lower MT-1H transcripts than pooled normal human controls. We here provide the first report of the differential expression of MT isoforms in human RCC and that this data further support the role of MT-2A in tumorigenesis.

Adult↗
PubMed2000

Platelet-derived growth factor (PDGF)-AA: a self-imposed cytokine in the proliferation of human fetal osteoblasts.

PDGF, a multiple mitogen, stimulates osteoblast replication and bone collagen degradation, and it has been described as a key factor in bone metabolism. Recently, PDGF was disclosed to be the autocrine cytokine of human osteoblasts. PDGF's effect on human bone development needs elucidation, and the mechanism of PDGF-AA autocrining remains unclear. In this work, osteoblasts were isolated from human fetal calvaria which resemble the cells in developing bone tissue. Using an in vitro model, the effect of PDGF-AA on the cells was investigated with the results showing that (i) after PDGF-AA was added into the medium for 24 h, PCI of the cells increased by 48.2% (P<0.05), and PCI decreased after the removal of PDGF-AA. (ii) 24 h after treatment with PDGF-AA, the percentage of osteoblasts in G(0)/G(1)phase decreased and that in S phase increased. (iii) The expression of PDGF-A mRNA was upregulated by PDGF-AA, PDGF-BB, TGFbeta,and bFGF respectively. These results proved that: (i) PDGF-AA enhances cell replication by accelerating cell recycle and inducing the quiescent cells into the proliferation portion of cell cycle. (ii) PDGF-AA is a self-imposed cytokine in human fetal osteoblast replication.

Bone Development↗
PubMed2000

Modulation of transforming growth factor beta to platelet-derived growth factor receptor-alpha of human osteoblasts.

OBJECTIVE: To investigate the mechanism and the significance of TGF beta in modulating the expression of Platelet-Derived Growth Factor Receptor-alpha (PDGFR-alpha) in human osteoblasts. METHODS: The osteoblasts were isolated from human fetal calvaria. The percentage of cell increase (PCI) in every 4 hours was calculated to demonstrate the proliferation of osteoblasts affected by PDGF-AA and TGF beta. The osteoblasts were cultured with TGF beta for 24 hours and with PDGF-AA for another 24 hours, and the cells proliferation was shown by PCI too. The osteoblasts were cultured with TGF beta for 24 h, and the PDGFR-alpha of the cells were measured by immunofluorescent analysis. RESULTS: PCI was increased by 48.2% and 22.4% after PDGF-AA and TGF beta were added into the medium for 24 hours respectively (P < 0.05), and PCI decreased after the removal of the two cytokines. Preincubated with TGF beta for 24 hours and then stimulated with PDGF-AA, PCI grew slowly. TGF beta downregulated the expression of the PDGFR-alpha. CONCLUSION: TGF beta can downregulate the mitogenesis of PDGF-AA by lowering the number of PDGFR-alpha.

Cell Division↗
PubMed2000

[Mitogenesis of platelet-derived growth factors to human osteoblasts modulated by basic fibroblast growth factor].

OBJECTIVES: To investigate the mechanism by which basic fibroblast growth factor modulates the mitogenesis of platelet-derived growth factor to human osteoblasts. METHODS: The osteoblasts isolated from human fetal calvaria were incubated with PDGF-AB (100 ng/ml) or bFGF(10 ng/ml) combined with PDGF-AB (100 ng/ml); the growth curve was plotted. The(3)H-TdR incorporation of the osteoblasts was measured after the cells were incubated with different combination of bFGF and PDGF-AA or PDGF-BB. After incubated with bFGF (10 ng/ml) for 24 hours, the number of PDGFR-alpha and PDGFR-beta on the membrane of the osteoblasts was detected by fluoroimmunoassay. RESULTS: Four days after PDGF-AB added into the medium, the population of the osteoblasts was larger than that of the control (P < 0.05). The number of the osteoblasts incubated with PDGF-AB (12.1 x 10(4)) was 1.8 times as large as the control (6.8 x 10(4)) in the 10th day (P < 0.05), and that of the osteoblasts incubated with both bFGF and PDGF-AB increased more quickly than the cells only incubated with PDGF-AB. The incorporation of (3)H-TdR into the osteoblasts cultured with bFGF combined with PDGF-AA (533.6 +/- 13.1) was more than that cultured only with PDGF-AA (435.4 +/- 14.8, P < 0.01), so was the incorporation of (3)H-TdR of those cells cultured with bFGF and then PDGF-AA (633.8 +/- 51.5). bFGF up-regulated PDGFR-alpha and down-regulated PDGFR-beta on the surface of the human osteoblasts. CONCLUSION: bFGF elevates the mitogenesis of PDGF-AA or -AB to human osteoblasts by up-regulating PDGFR-alpha.

Cell Proliferation↗
PubMed1999

Psychological conditions diagnosed among veterans seeking Department of Defense Care for Gulf War-related health concerns.

The Comprehensive Clinical Evaluation Program is a US military program that provides a voluntary, clinically oriented evaluation for Gulf War health concerns. This article presents administrative data on psychological conditions (as coded using the International Classification of Diseases, 9th Revision) from the first year of the program. The most commonly diagnosed psychological conditions were medically unexplained physical-symptom syndromes; depression and anxiety, including post-traumatic stress disorder; and alcohol abuse or dependence. Psychological conditions were significantly related to a higher number of workdays lost, and the 19% of veterans with a primary diagnosis of a psychological condition reported 28% of the lost workdays among veteran who participated. Stressful Gulf War experiences were weakly but significantly related to psychological conditions. We conclude that among Gulf War veterans seeking evaluation for Gulf War-related health concerns, psychological conditions are common and are associated with important occupational morbidity.

Adult↗
PubMed1999

[Collagen expression of intra-acinar pulmonary arteries and right ventricle and intervention of Radix Astragali in rats with hypoxic pulmonary hypertension].

OBJECTIVE: To investigate the collagen expression effect of intra-acinar pulmonary arteries and the right ventricle and to observe the intervention effect of Radix Astragali in rats with hypoxic pulmonary hypertension. METHODS: Wistar male rats were divided into three groups: hypoxia group, which was fed in hypoxic environment (oxygen concentration was 9%-12%) under normal atmospheric pressure for three weeks (12 hours every day); intervention group, which was abdomenly injected with Radix Astragali and fed in the same environment as hypoxia group; and control group, which was fed in normal environment. Pulmonary artery pressure and cardiac output of the right ventricle were measured with catheterization and Fick's method. Protein expression of collagen in intra-acinar pulmonary arteries was assessed with histopathologic method. mRNA expressions of collagen in the right ventricle, and endothelin-1 and nitric oxide synthase in lung tissue were evaluated by RT-PCR technique. RESULTS: Compared with those in control group, pulmonary artery pressure and protein expression of collagen in intra-acinar pulmonary arteries and mRNA expression of type I collagen in the right ventricle and endothelin-1 in lung tissue were obviously increased in hypoxia group (mean pulmonary artery pressure: (24.8 +/- 3.6) mm Hg vs (18.8 +/- 1.7) mm Hg, P < 0.01; protein expression of collagen: (20.4 +/- 4.5) AU vs (3.4 +/- 1.1) AU (P < 0.01), but mRNA expression of nitric oxide synthase in lung tissue was declined. Compared with the data obtained in hypoxia group, cardiac output and mRNA expression of nitric oxide synthase in lung tissue were raised in intervention group (cardiac output: [(141 +/- 20) ml/min vs (118 +/- 40) ml/min, P < 0.01], but protein expression of collagen in intra-acinar pulmonary arteries and mRNA expression of type I collagen in the right ventricle and endothelin-1 in lung tissue were markedly decreased (protein expression of collagen: [(5.6 +/- 1.2) AU vs (20.4 +/- 4.5) AU, P < 0.001]. CONCLUSION: Changes of collagen expression in intra-acinar pulmonary arteries and right ventricle are one of the most important features in remodeling of pulmonary arteries and right ventricle in hypoxic pulmonary hypertension. Radix Astragali can partly inhibit the remodeling of pulmonary arteries and right ventricle, and regulate mRNA expression of endothelin-1, nitric oxide synthase, and collagen, thus contributing to the treatment of hypoxic pulmonary hypertension.

Animals↗
PubMed1999

[The study on edge detection method of medical color image].

Considering the specificity of the medical color image, in this paper a medical color image is decomposed as three color orthogonal feature: I1, I2 and I3 in K-L transformation method, and Kirsch algorithm is used to detect the edge of the monochrome image I1 including rich information. Finally, both clarity edge and rich detail of color backdisplay image are gained, if we adopt I2 and I3 to compensate I1.

Algorithms↗
PubMed1998

[A study of genetic heterogeneity in Pfeiffer syndrome].

OBJECTIVE: To understand the molecular pathology of Pfeiffer syndrome. METHODS: DNA from peripheral blood was examined in 4 families with Pfeiffer syndrome by SSCP-sequence analyses and PCR-restriction enzyme digestion. RESULTS: The authors found the mutations of FGFR2 gene in two families, an A to G transition in the 3' acceptor splice site of intron 8 in a family, and Asp321 Ala substitution in exon 9 in another family. In addition, the mutation in exon 5 of FGFR1 gene (Pro252Arg) was found in a family. CONCLUSION: These findings reveal the genetic heterogeneity of Pfeiffer syndrome and can help one understand the molecular mechanism of the disease.

Acrocephalosyndactylia↗
PubMed1998

Scattered radiation in scanning slot mammography.

Monte Carlo simulations were used to quantify the amount of scattered radiation a scanning slot detector geometry designed for use in digital mammography. Ratios of the scatter to primary (S/P) x-ray photon energy absorbed in the detector were obtained for a Lucite phantom, and were investigated as a function of photon energy, phantom thickness, and slot detector width. Over a Lucite phantom thickness range of 2-6 cm, the S/P ratios range from about 0.10 to 0.17 for a 4 mm wide slot detector at the x-ray photon energies used in mammography. These ratios increased by a factor of approximately 1.8 when the slot width was increased to 10 mm. In general, 20 keV photons gave S/P ratios similar to those of a 30 kVp x-ray spectrum (Mo target + 30 microns Mo filtration). The use of a 3 cm air gap reduced the S/P ratios by a factor of between 2.5 and 3.4, depending on the phantom thickness. For a constant primary energy fluence, coherent scatter was reduced as photon energy increased, whereas Compton scatter increased with increasing photon energy. With no air gap, the contributions of coherent and Compton scatter were found to be equal at 25 keV, whereas the introduction of a 3 cm air gap resulted in equal contributions for the two scatter processes at 36 keV. A 10 mm wide slot detector consisting of a 36.7 mg/cm2 thick Gd2O2S:Tb phosphor screen was compared to an ideal detector absorbing all incident primary/scatter photons. Average differences in the S/P ratios for these two detectors were 7% with no air gap and approximately 4% with a 3 cm air gap. The results obtained in this study will assist in the design of an optimal slot detector for use in digital mammography.

Breast↗
PubMed1998

[Detection of 17-ketosteroid and 17-hydroxycorticosteroid in urine after separation and collection by foam rubber].

Using foam rubber 17-ketosteroid (17-KS) and 17-hydroxycorticosteroid (17-OHCS) were separated and collected in urine. 17-KS and 17-OHCS were eluted down from the foam rubber with alcohol, colour reaction can be respectively produced by m-dinitrobenzene and phenyhydrazine hydrocholoride, then both of them were detected by spectro-photometry. The standard deviation of this method was +/- 0.032, and its minimum detectable concentration was 0.01 microgram.ml-1. The recovery rate of 17-KS and 17-OHCS estimation was from 99.0% to 101.0%, with co-efficients of variation less than 6.23%.

17-Hydroxycorticosteroids↗