Search PubMed⌕ Search

Biomedical subjects

Jun Gao

Publications and source records attributed to Jun Gao.

72 records · Page 4Linked to original sources

Research on the genetic variations of a1-fucosytransferase (FUT1) gene in 26 pig breeds.

Enterotoxigenic Escherichia coli F18(ECF18) is a main pathogen that causes edema disease and post-weaning diarrhoea in piglets, and al-fucosytransferase (FUT1) gene has been identified as a candidate gene for controlling the expression of the receptor for ECF18 bacteria. The genetic variations at position 307 nucleotide in open reading frame of FUT1 gene in 26 pig breeds (total 1458 individuals) from 5 western commercial pig breeds and 21 Chinese native pig breeds were investigated by PCR-RFLP. The results showed that the genetic polymorphisms of the FUT1 locus were only detected in 5 western pig breeds and the Chinese Lingao pig breed, 5 western pig breeds possessed 3 different genotypes, and Lingao pig breed had two susceptible genotypes GG and AG, while all the other 20 Chinese native pig breeds only presented the susceptible genotype GG. The results indicated that if M307G-A point mutation in the coding region of FUT1 gene was the key factor determining the expression of the ECF18 receptor, most of Chinese native pig breeds were absent of the genetic background on the resistance to ECF18 bacteria. In this case, it was inferred that the resistance gene to ECF18 might be originated from western pig breeds. In addition, it is of great importance for the conservation of Lingao pig breed as it is the only found Chinese native pig breed possessing resistance M307A allele in FUT1 gene. Generally, compared with exotic pig breeds, Chinese native pig breeds have stronger resistance to edema disease and post-weaning diarrhoea in piglets. The results suggested that further study should be done to identify and characterize putative QTL (quantitative trait locus) or/and the functional gene responsible for the resistance to ECF18 in Chinese native pig breeds.

Alleles↗

[Studies of the relationship of melanocortin receptor 1(MC1R) gene with coat color phenotype in pigs].

Although coat color in pigs has no direct relation with economic traits, it affects economic benefit significantly, coat color selection are widely used in pig breeding and production. PCR-Acc II-RFLP, PCR-BspH I-RFLP and PCR-SSCP were used in combination to analyze genotype at MC1R locus among individuals from 16 full-sib pedigrees and 6 Chinese native breeds including Jinhua, Jiaxing Black, Yushan Black, Leping Spotted, Shanggao Spotted and Shengxian Spotted pig. It was found that the Chinese native pig breeds carry a dominant black allele at MC1R at high frequency, this ED1 allele was suggested to be the major allele controlling black coat color in Chinese native pig breed. In addition, the evidence for a new allele was obtained in Shengxian Spotted pigs by PCR-SSCP analysis. It was reconfirmed from the result of pedigree analysis that ED1 was dominant over EP and e, while EP was incompletely dominant over e.

Alleles↗

[Ecological benefit assessment of urban vegetations by remote sensing and GIS].

As an important part of the urban ecosystem, urban vegetation plays an important role in improving urban environmental quality. The assessment of ecological benefits of urban or regional vegetations can help us more properly plan urban green space pattern, optimize urban vegetation structure, and further strengthen ecological construction. Through the discussion of the relevant researches at home and abroad, it's indicated that remote sensing and GIS could help as better evaluate the ecological effect of urban vegetations. This article introduced the UEA method adopted by AMERICAN FORESTS and CITYgreen software working with ArcView 3.2, as to make the best use of remote sensing and GIS in evaluating urban vegetation ecological effect quantitatively, and to promote sustainable development and ecological construction.

City Planning↗

[Polymorphism analysis of porcine myogenin gene by PCR-RFLP].

The polymorphisms of porcine myogenin gene in 561 pigs including Duroc, Landrace, Large Yorkshire, Nanchang white pig, Erhualian, Meishan, Yushan black pig, Leping spotted pig, Jinhua black head-hind pig and Shanggao black head-hind pig were detected by PCR-RFLPs with three different pairs of primers,and the PCR products were digested by MspI. The results showed that most of the Duroc, Landrace, Large Yorkshire, Nanchang white pigs presented as AA genotype, while more animals of the six Chinese local pig breeds except for Leping spotted pig presented as BB genotype at PCR1 MspI-RFLP site. The six Chinese local breeds presented as MM genotype except that one Yushan black pig presented as MN genotype, while more swines of the exotic breeds including Duroc, Landrace, Large Yorkshire presented as NN genotype, and Nanchang white pig appeared to be closer to the exotic breeds at PCR2 MspI-RFLP site. PCR product was obtained in all the swine by PCR3, but the MspI restriction site was not found in the tested pig breeds including Meishan and blood closely related Erhualian pig.

English Abstract↗

[Studies of microsatellite isolation from porcine PAC clone].

A novel microsatellite DNA was isolated from a single porcine PAC clone by sequencing the PAC clone directly with (CA)n repeat motif anchored primer. The specific primer pairs flanking the (CA)n repeat region were used to amplify the genomic DNA of 40 individuals from 8 pig breeds, which detected three alleles with the fragment length of 305 bp, 307 bp and 309 bp. The PCR product sequencing results of homozygous animals representing three alleles revealed that those three alleles contained 12,13 and 14 CA dinucleotide repeats respectively.

English Abstract↗

[Primary biliary cirrhosis: an analysis of 153 cases].

OBJECTIVE: To study the clinical, immunological and pathological features of primary biliary cirrhosis (PBC). METHODS: Clinical and laboratory data of 153 patients with PBC treated in our hospital were retrospectively analyzed. Of these patients, 35 underwent hepatic biopsy. RESULTS: Typical manifestations such as itch of skin and hepatosplenomegaly etc. were found in only 39.2% to 46.4% of the patients and jaundice was seen in 84.3%. The serum level of SB was gradually increased while that of CHE decreased along with progression of PBC (P < 0.01). The level of serum Albumin and ALT was significantly lower in late stage than in the early stages (P < 0.05). ALT and CHE were not correlated with SB. AST level was markedly higher in the late stage than in the early stage (P < 0.05). The levels of ALP and GGT rose at the early stage but remarkably decreased at the middle stage (ALP, P < 0.05) and at the late stage (GGT, P < 0.01). The positive rate of AMA was 83.7% and that of M2 69.3%. As for the 35 patients receiving hepatic biopsy, 10 were AMA positive and the other 25 AMA negative. CONCLUSION: More than half of the patients with PBC do not exhibit typical clinical symptoms and over 80% of the cases of PBC can be diagnosed by investigation of clinical features and detection of AMA and M2. For some cases that can not be definitely diagnosed by observation of clinical features, the final diagnosis should be determined by hepatic biopsy.

Adolescent↗

Modulation of serotonergic projection from dorsal raphe nucleus to basolateral amygdala on sleep-waking cycle of rats.

Putative serotonergic dorsal raphe nucleus (DRN) neurons display a dramatic role in the modulation of behavior. However, it is not clear how this modulation is mediated. The present study investigated the modulatory effects of serotonergic projection of the DRN to the basolateral amygdala (BLA) on the sleep-waking cycle using polysomnograph (PSG) in rats. DRN microinjection of kainic acid (KA) caused insomnia immediately. From the third day, however, slow wave sleep (SWS) and paradoxical sleep (PS) increased markedly. DRN microinjection of p-chlorophenylalanine (PCPA, once a day for 2 days), which inhibits the synthesis of serotonin (5-HT), led to similar effect to KA administration. The percent of sleep-wakefulness began to change on the third day after PCPA microinjection into the DRN, and the effect was most significant on the sixth day. The percent of sleep-wakefulness started to resume on the seventh day. SWS and PS were reduced after excitation of DRN neurons by microinjection of L-glutamate (L-Glu) into the DRN. Preapplication of the nonselective 5-HT receptor antagonist methysergide (MS) into bilateral BLA blocked the effect of DRN microinjection of L-Glu. Furthermore, bilateral BLA microinjection of 5-hydroxytryptophan (5-HTP), the precursor of 5-HT, on the sixth day after microinjection of PCPA into the DRN, could reverse the effect of PCPA microinjection. These results indicate that the modulation of the DRN on sleep is partially mediated by the serotonergic projection of the DRN to the BLA.

5-Hydroxytryptophan↗

Characterization of diet-induced obese rats that develop persistent obesity after 6 months of high-fat followed by 1 month of low-fat diet.

A subset of Sprague-Dawley rats developed persistent obesity when maintained on a high-fat diet for 6 months followed by a low-fat diet for 1 month, while another subset from the same cohort of rats remained lean on the same diet regimens. The diet-induced obese (DIO) rats had higher energy intake than expenditure, while diet-resistant (DR) rats maintained energy balance. DIO rats also had an increased respiratory quotient and higher levels of plasma leptin, insulin and cholesterol. In the hypothalamic areas, DIO rats had elevated NPY and AGRP mRNA, but not MCH mRNA. Our data suggest that the increase in hypothalamic expression of NPY and AGRP may contribute to the development of persistent obesity in DIO rats.

Agouti-Related Protein↗

[Relationship between HLA-DQA1, -DQB1 genes polymorphism and susceptilibity to bronchial asthma among Northern Hans].

OBJECTIVE: To investigate the relationship between human leukocyte antigen (HLA)- DQA1, -DQB1 genes polymorphism and susceptibility to bronchial asthma among the Hans in the northern China. METHOD: Sequence-specific primer polymerase chain reaction was used to gene frequencies of HLA-DQA1 and HLA-DQB1 genes among 125 unrelated asthmatics, 12 of which being probands of asthmatic pedigrees, and 96 healthy controls, all of Han nationality and living in Beijing or nearby areas for a long time. Radioimmunosorbent test was used to examine the serum IgE and TigE. The ventilatory function was test among the asthmatics. RESULTS: The frequencies of HLA-DQA1 0104 and HLA-DQB1 0201 were 0.204 and 0.284, significantly higher than those in the healthy controls (0.089 and 0.096 respectively, both P < 0.01). Conversely, the frequencies of HLA-DQA10301 and HLA DQB101301 in the asthmatics were 0.148 and 0.20, significantly lower than those in the controls (0.25 and 0.282 respectively, P < 0.01 and < 0.05). The correlation coefficients between HLA-DQA1 * 0104 and atopy, HLA-DQB1 * 0201 and atopy, and HLA-DQA1 * 0301 and atopy were 0.813 (P < 0.01), 0.289 (P < 0.01), and -0.168 (P < 0.05) respectively. Multi-variate logistic regression asthma. CONCLUSIONS: The alleles HLA-DQA1 * 0104 and HLA-DQB1 * 0201 are correlated with the susceptibility to asthma among Northern of Han nationality. HLA-DQA1 * 0104 is an independent risk factor of onset of asthma. The alleles HLA-DQA1 * 0301 and HLA-DQB10301 are correlated with resistance against asthma. HLA-DQ genes are involved in the regulation of human specific immune responses.

Adult↗

Gel protein capillary extraction apparatus. electronic protein transfer.

A gel protein capillary extraction apparatus is developed and demonstrated for its rapid and effective transfer of SDS-protein complexes from polyacrylamide gel to a fused-silica capillary. The small dimensions of capillary columns permit the application of high voltages for achieving rapid and effective transfer of gel proteins. Furthermore, the fused-silica capillaries are internally coated with polyacrylamide for the elimination of electroosmotic pumping and protein adsorption onto the capillary wall. The extracted proteins are present in a highly concentrated solution plug as the result of field amplification and sample stacking during the extraction process. Three model proteins, including cytochrome c (14 kDa), ovalbumin (45 kDa), and beta-galactosidase (116 kDa), are visualized using coomassie blue staining and electrophoretically extracted from the gels with protein loading as low as 50 ng. The SDS-cytochrome c complexes extracted from a 50-ng protein loading are concentrated in a 30-nL solution plug inside the capillary with an estimated concentration of 0. 1 mg/mL or 10(-5) M. The capillary format allows the straightforward integration of a miniaturized trypsin-membrane reactor for on-line proteolytic digestion and ESI-MS analysis for protein/peptide identification.

Calibration↗

High-resolution chiral separation using microfluidics-based membrane chromatography.

A plastic microfluidic system, containing porous poly(vinylidene fluoride) (PVDF) membranes adsorbed with bovine serum albumin (BSA), is demonstrated for high resolution chiral separation of racemic tryptophan and thiopental mixtures. Microfluidic networks on poly(dimethylsiloxane) (PDMS) substrates are fabricated by capillary molding technique. This miniaturized chiral separation system consists of two layers of PVDF membranes which are sandwiched between two PDMS slabs containing microchannels facing the membranes. On-line adsorption of BSA onto the membranes is employed for the preparation of chiral stationary phase and the evaluation of solution conditions in an effort to achieve maximum protein adsorption. Variations in the mobile phase conditions, including solution pH and ammonium sulfate concentration, are studied for their effects on chiral separation. Based on the large surface area to volume ratio of porous membrane media, adsorbed BSA onto the PVDF membranes enables high resolution separation of racemic mixtures with sample consumption of sub-nanogram or less in the integrated microfluidic networks. In addition, the membrane pore diameter in the submicron range eliminates the constraints of diffusional mass-transfer resistance during protein adsorption and chiral chromatographic processes.

Adsorption↗

Health equity in transition from planned to market economy in China.

This paper examines the impact of economic transition and health sector reform on health equities in the urban and rural populations of China in the 1990s. Since 1980, China has experienced a rapid economic development and fundamental transformation of its society. Three secondary data sources were used as the basis for the analysis and discussion: mortality data from the National Death Notification System; infant mortality from the National Maternal and Child Health Surveillance System; and morbidity, health care utilization and financing data from the National Health Household Interview Surveys. The analysis revealed a very complex picture with: general mortality rates decreasing in both urban and rural populations, but the differences between urban and rural increasing; declining infant mortality rates with narrowing of the urban-rural gap; health care needs declining in both urban and rural populations, but more rapidly in the urban areas; health service payments increasing in both urban and rural areas, while, at the same time, health insurance coverage decreased. The analysis suggests that despite overall improvements in the population's health status, the economic and health system policy reforms are leading to increased inequities in health care. The lowest income quintiles in both urban and rural areas are receiving less health care compared with their needs in 1998 than in 1993, and the urban-rural divide, in particular with regard to receiving inpatient health care, is widening appreciably. The reform of the health insurance system, combined with the market setting of prices for care, have had profound implications for all population groups, in particular the lower income segments and the rural populations. During the period 1993-98 the proportion of the urban population that had to cover the increasing cost of medical care themselves doubled.

China↗

[Relationship of growth hormone (GH 2) genotypes with some production performances in pig].

The genotypes of 117 Nanchang White pigs and 361 Large Yorkshire pigs at GH 2 locus were detected by PCR-RFLP. The PCR products were cut by Apa I, and produced two alleles: A(449 + 101 + 55 bp), and B(316 + 133 + 101 + 49 bp). Effects of different genotypes on some important production traits involving the birth weight, 2-month body weight, 6-month body weight, corrected back-fat thickness, average back-fat thickness, feed to gain ratio and lean percentage were analyzed. The results showed that in Nanchang White pigs, no significant differences were observed between different genotypes and different growth and carcass traits; while in Large Yorkshire, the pigs with BB genotype had more lean percentage than pigs with AA genotype (P < 0.05).

Adipose Tissue↗

[Studies of population genetic relationships among 24 Chinese and exotic pig breeds using AFLP analysis].

A total of 12 AFLP primer combinations were used to detect genetic variation of pooled DNA in a sample of 19 Chinese native pig breeds, 1 cultivated pig breed and 4 European and American pig breeds. The genetic similarity coefficient of 24 pig beeds was calculated from AFLP data, UPGMA cluster analysis was also performed. The 12 primer combinations generated more than 1000 bands, of which 208 bands were polymorphic, 17.3 polymorphic markers were detected by one primer combination on the average. Thirteen putative breed specific bands were produced in the pooled DNA of 8 pig breeds. The cultivated pig breed and 4 exotic pig breeds were clustere into one group, while 19 Chinese native pig breeds were gathered into the other group in the UPGMA tree. The result indicated that AFLP analysis had high assay efficiency index (Ai) and provided a valuable tool for assaying genetic diversity and breed characterization in pigs. Chinese native pig breeds and exotic pig breeds show remarkable genetic differentiation, which had farther genetic relationships. Nanchang White pig and Large White pig, Yushan Black pig and Yanshan Black pig had intimate genetic relationships with each other respectively, which were consistent with its breeding history, geographical distribution and RAPD analysis results. In addition, the reasons for cluster results of some pig breeds from AFLP data were not consistent with morphology, geographical distribution and existing classification were discussed.

Animals↗

[Association of polymorphism of human beta 2-adrenergic receptor gene and bronchial asthma].

OBJECTIVE: To investigate whether beta 2-adrenergic receptor gene (beta 2AR) polymorphism at position 16, 27, 164 is in association with asthma susceptibility or asthmatic phenotype (including nocturnal asthma, serum IgE level, bronchial responsiveness, the status of asthmatics). METHODS: By using PCR-RFLP and allelic-specific PCR (ASP), the polymorphism of beta 2AR gene at position 16, 27, 164 in 125 Han origin asthmatics and 96 normal healthy controls with the same ethnic nearby Beijing region were genotyped. All patients had their serum total IgE (TIgE) measured by RAST, pulmonary ventilatory function assessed by FEV1% and FEV1/FVC, bronchial responsiveness challenged by methacholine (if FEV1% > 70%), and brocho-reversibity by inhaling beta 2-agonist. RESULTS: There was higher prevalence of Gly16 homozygous of beta 2AR in asthmatics than that in normal healthy controls (22.4% vs 8.3%, P < 0.05), with odd ratio (OR) 2.918 (95% CI: 1.256-6.781); Also there was higher frequency of Gly16 homozygous of beta 2AR in nocturnal asthmatics than that in nonnocturnal asthmatics (35.3% vs 13.5%, P < 0.01), but Gly16 homozygous of beta 2AR was low an independent risk factor for the pathogenesis of asthma. The dose of methacholine was low in asthmatics carrying Gln27 homozygous beta 2AR than Glu27 homozygous beta 2AR and Gln/Glu27 heterozygous beta 2AR in brocho-challenge test [(0.205 +/- 0.275) vs (2.11 +/- 3.00) vs (1.575 +/- 0.828) mumol, P < 0.05]. CONCLUSIONS: Gly16 homozygous beta 2AR was associated with asthma susceptibility in Chinese patients with Han ethnic nearby Beijing region, and Gly16 homozygous beta 2AR was associated significantly with nocturnal asthma. Glu27 homozygous beta 2AR was related to hyper-bronchial reactivity of asthmatics.

Asthma↗

[Comparitive study of the threshold variability between blue-on-yellow perimetry and white-on-white perimetry].

PURPOSE: To compare the threshold variability of blue-on-yellow (B/Y) perimetry with white-white(W/W) perimetry, and evaluate the reproducibility of B/Y perimetry. METHODS: The B/Y perimetry and W/W perimetry in the Octopus 101 perimetry were used to examine the visual fields of 12 normal subjects (24 eyes), 16 cases (32 eyes) of primary open angle glaucoma (POAG), and 7 cases (14 eyes) of suspected POAG respectively. The B/Y perimetry and W/W perimetry were repeated to examine within 2 weeks. The point by point threshold variability of the two perimetries were compared and analysed. RESULTS: The total mean threshold variability for B/Y perimetry (2.61 +/- 0.94) dB was greater than that for W/W perimetry (2.11 +/- 0.90) dB in all subjects, but it had no significance (P = 0.6244). The total mean threshold variability for B/Y perimetry (2.07 +/- 0.54) dB was significantly greater than that for W/W perimetry (1.50 +/- 0.34) dB in normal subjects (P = 0.0006), while no significance was found in suspected POAG and POAG groups between the two perimetries (P = 0.0523 and 0.9371). The threshold variability in the areas of some eccentricities for B/Y perimetry were significantly greater than that for W/W perimetry in normal subjects and suspected POAG group, but no significance was found in POAG group for all eccentricities between the two perimetries. CONCLUSION: The threshold variability for B/Y perimetry was greater than that for W/W perimetry in normal subjects, but no significance was found in suspected POAG and POAG between the two perimetries.

Adult↗

Factors affecting the implementation of health legislation and its impact on the rural poor in China: a case study of implementation of the maternal and infant health care law in two poor counties.

This paper presents and discusses a case study of health legislation in China. In the transition to a market economy, legislation has been developed to offset the weakening in the central planning mechanism and political control that have historically influenced the behaviour of institutions and individuals in the Ministry of Health. There has been relatively little empirical examination of the implementation and impact of legislation as a tool for influencing health service provision in low-income countries. The study aimed to contribute towards filling this gap by exploring the factors affecting the implementation and impact of the Maternal and Infant Health Care Law, through a case study of two poor, rural counties in Chongqing municipality, China. The study found that key local actors perceive health legislation to be an important tool for safeguarding access to essential health care. However, the implementation of health legislation is inevitably a political process. The study illustrates the difficulties involved in efforts to influence provider behaviour through a national level legislative framework in a situation of decentralization of control over those providers, due to extreme regional variation in economic situations and limited resource inputs from the centre. Lessons are drawn for Chinese and international policy makers.

Child Health Services↗

Dynamic enhancements of sample loading and analyte concentration in capillary isoelectric focusing for proteome studies.

Capillary isoelectric focusing (CIEF) involves the use of the entire capillary filled with a mixture containing protein/peptide analytes and carrier ampholytes. Thus, the preparative capabilities of CIEF are inherently greater than most capillary-based electrokinetic separation techniques. To further increase sample loading and, therefore, the concentrations of focused analytes, a dynamic approach, which is based on electrokinetic injection of proteins/peptides from a solution reservoir, is demonstrated using a low p/ protein calibration kit and tryptic peptides from Saccharomyces cerevisiae. The proteins/peptides continuously migrate into the capillary and encounter a pH gradient established by carrier ampholytes originally present in the capillary for focusing and separation. Dynamic introduction and focusing in CIEF can be directly controlled by various electrokinetic conditions, including the injection time and the applied electric field strength. Differences in the sample loading are contributed by electrokinetic injection bias and are affected by the individual analyte's electrophoretic mobility. Depending on the mobilities of yeast peptides, the loading capacity of each peptide is measured to be around 8 to 45-fold of that obtained in conventional CIEF. By comparing with the concentrations of dilute yeast peptides originally present in the reservoir, an overall concentration factor of 1400-7700 together with excellent separation resolution is achieved using dynamic introduction and focusing. This concentration effect is further illustrated by detecting 10 pg/microL of bradykinin peptide spiked in yeast protein digest using only ultraviolet absorption.

Chemistry Techniques, Analytical↗