Biomedical subjects

Ling Zhou

Publications and source records attributed to Ling Zhou.

At least 37 records · Page 2Linked to original sources

PubMed2005

[The pulmonary protective effects of leukocyte depletion with a modified filter located at the cardiopulmonary bypass (CPB) venous line in canine].

OBJECTIVE: To investigate the pulmonary protective effects of short-term leukocyte depletion with a modified filter located at the CPB venous line in canine. METHODS: Sixteen healthy hybrid canines were randomly allocated to the LD-1 group, with an LD-1 filter installed in the CPB venous-line for a 5-minute leukocyte depletion at the beginning of the CPB, and to the control group. Blood samples were taken for routine test respectively at 9 time-points, namely pre-CPB, at 5, 10, 40, 70 min of the CPB, 5 min after aortic cross-clamp being off, at the discontinuation of the CPB, 5 min after protamine being administered, and 2 h after the CPB. Oxygen index (OI), pulmonary pathology and levels of interleukin-6 (IL-6) and interleukin-8 (IL-8) in plasma were measured at pre-CPB, 5 min after protamine being administered and 2 h after the CPB respectively. The levels of IL-6 and IL-8 in the bronchial alveolar lavage fluid (BALF) were measured at 2 h after the CPB. RESULTS; In LD-1 group, white blood cell (WBC) counts were significantly less than those in control group at 5 min of the CPB (P < 0.05), the filtration rate of WBC was (65.72 +/- 9.36)%. The WBC counts showed no significant difference in either group from 40 min of the CPB to 2 h after the CPB. OI was higher in LD-1 group than that in control group (P < 0.05) at 5 min after protamine being administered and 2 h after the CPB. There was significantly less WBC infiltration and alveolar edema of the lung in LD-1 group than that in control group at 5 min after protamine being administered and 2 h after the CPB. There were no significant differences of IL-6 and IL-8 in plasma between the two groups at 5 min after protamine being administered (P > 0.05), but the levels of IL-6 and IL-8 were much lower in the LD-1 group than those in the control group at 2 h after CPB. At 2 h after the CPB, IL-6 level in the BALF showed no significant difference in each group (P > 0.05); however, the level of IL-8 was lower in LD-1 group than that in control group (P < 0.05). CONCLUSION: The LD-1 filter in the CPB venous-line in canine model used for short-term leukocyte depletion filtration could reduce WBC counts significantly, decrease the levels of IL-6 and IL-8 in plasma, attenuate inflammatory response in the lung after CPB, so it has protective effect on canine lung.

Animals↗

PubMed2005

[Study on the effect of embryo extraction of chicken on improving the hemophthisis of malnutrition in rat].

OBJECTIVE: To study the effect of embryo extraction of chicken on improving the hemophthisis of malnutrition in rats. METHODS: The rats model of hemophthisis was established with the method of feeding the low iron feed and blood letting in caudal vein. The effect of embryo extraction of chicken on the biochemistry index of hemoglobin, serum transferrin saturation, serum ferritin, serum iron and organize iron were observed after the model rats were fed with the embryo extraction of chicken four weeks. RESULTS: The hemoglobin, serum transferrin saturation, serum ferritin, and serum iron can be increased remarkably by embryo extraction of chicken in the model of hemophthisis of rats. There is no side effect on the weight in rats. CONCLUSION: The embryo extraction of chicken holds a good function on improving the hemophthisis of malnutrition in rats.

Anemia, Iron-Deficiency↗

PubMed2005

[The relationship between the beta-2-adrenergic receptor gene +46 Arg 16/Gly variant and serum level of low density lipoprotein-cholesterol in Kazakans of Xinjiang].

OBJECTIVE: To investigate the distribution of beta-2-AR +46 A-->G variant in Kazakans of Xinjiang and the relationship of the variant with low density lipoprotein-cholesterol (LDL-C) level in this population. METHODS: The genotypes of beta-2-AR gene Arg16/Gly variant were detected by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique in 506 Kazakans with age from 30 to 69, and its distribution and relationship to LDL-C level were investigated. RESULTS: (1) The frequencies of genotypes AA, AG, GG and alleles A, G of beta-2-AR +46 variant in this population were 0.310, 0.455, 0.235 and 0.538, 0.462 respectively, which were accorded with Hardy-Weinberg equilibrium. (2) The Gly16/Gly genotype had highest LDL-C level in the three genotypes, and were significantly higher than Arg16/Gly genotype (P < 0.05). (3) Comparing the effect of beta-2-AR gene +46 variant on serum lipid in males with females, we found that females with Gly16/Gly genotype had the highest level of serum LDL-C. CONCLUSIONS: These data show that Gly16/Gly genotype of beta-2-AR gene +46 A-->G variant is associated with higher level of serum LDL-C in this population, especially in female.

Adult↗

PubMed2005

[Forward efficacy of lacrimal passage obstruction treated by double frequency YAG laser].

PURPOSE: To study the forward efficacy of lacrimal passage obstruction in different location treated by frequency-doubled YAG laser. METHODS: The forward efficacy of obstruction at different lacrimal passage located in 66 eyes from 64 cases treated by frequency-doubled Nd:YAG laser respectively were analyzed. RESULTS: The forward cure rate of stenosis of the puncta, dacryogogatresia, and common lacrimal duct stenosis is 100%, 94% and 89% respectively. As for dacryocystorhinostenosis, lower to 29%. CONCLUSION: Frequency-doubled YAG laser is more fit for puncta stenosis, dacryogogatresia and common lacrimal duct stenosis. Choosing the other treatment is suitable to dacryocystorhinostenosis which is accompanied by chronic dacyocystitis for YAG laser' s poor forward efficacy.

Adult↗

PubMed2004

Prevalence and age-related variation of Cryptosporidium species and genotypes in dairy calves.

Fifteen dairy farms in seven states on the east coast of the US were each visited on two consecutive years to determinate the prevalence of Cryptosporidium species in pre-weaned (5 days to 2 months) and post-weaned calves (3-11 months), respectively. After each of 971 fecal specimens collected directly from each calf was sieved and subjected to density gradient centrifugation to remove debris and concentrate oocysts, specimens were examined by immunofluorescence microscopy, and polymerase chain reaction (PCR). For all PCR-positive specimens the 18S rRNA gene of Cryptosporidium was sequenced. Cryptosporidium was identified from all farms. Types of housing appeared to have no influence with regard to prevalence of infection. Of 971 calves, 345 were infected with Cryptosporidium (35.5%), but more pre-weaned calves (253 of 503; 50.3%) than post-weaned calves (92 of 468; 19.7%) were found to be infected. A total of 278 PCR-positive specimens characterized by gene sequencing revealed Cryptosporidium parvum, Cryptosporidium andersoni, and two unnamed Cryptosporidium genotypes Bovine B (AY120911) and deer-like genotype (AY120910). The prevalence of these Cryptosporidium species and genotypes appeared to be age related between pre- and post-weaned calves. C. parvum, the only zoonotic species/genotype, constituted 85% of the Cryptosporidium infections in pre-weaned calves but only 1% of the Cryptosporidium infections in post-weaned calves. These findings clearly demonstrate that earlier reports on the presence and prevalence of C. parvum in post-weaned cattle that were based solely on oocyst morphology must be reassessed using molecular methods to validate species and genotype. This finding also indicates that persons handling or otherwise exposed to calves under 2 months of age are at greater risk of zoonotic infection from Cryptosporidium than the risk of infection from exposure to older calves.

Age Factors↗

PubMed2004

[Release of hepatocyte growth factor mediated by heparin].

OBJECTIVE: To observe the effects of sodium heparin and low molecular weight heparin on the release of plasma hepatocyte growth factor (HGF) in senior coronary heart disease patients. METHODS: Fifty-four senior patients with coronary heart disease were divided into three groups: intravenous sodium heparin, subcutaneous sodium heparin, and subcutaneous low molecular weight heparin (LMWH). Plasma HGF and vascular endothelial growth factor (VEGF) were measured before and after injection. RESULTS: Plasma HGF was increased rapidly and significantly after intravenous injection of sodium heparin, reaching its peak level (about 48 fold) after approximately 10 minutes. Plasma HGF was also increased rapidly and significantly after subcutaneous injection of sodium heparin and LMWH, reaching its peak level (about 4 and 5 fold in sodium heparin and LMWH respectively) after approximately 2-3 hours. CONCLUSION: The rise of plasma HGF after heparin treatment suggests that heparin has some other biological effects in addition to its anticoagulant property through HGF. By this mechanism, the administration of heparin may be of some importance in the reparation of cardio-vascular diseases.

Aged↗

PubMed2004

Trapidil inhibits monocyte CD40 expression by preventing IFN-gamma-induced STAT1 S727 phosphorylation.

Trapidil is a triazolopyrimidine that has been found to prevent restenosis after vascular injury. Although its precise mode of action is still unclear, several biological effects have been described including inhibition of IFN-gamma-induced CD40 expression on monocytes. Herein, we investigated the molecular mechanisms by which Trapidil exerts this inhibitory action. First, we observed that the inhibition of CD40 expression is associated with the suppression of CD40 gene transcription, as demonstrated by a clear decrease of CD40 nuclear RNA (nRNA) levels and unchanged CD40 mRNA half-life. IFN-gamma-induced CD40 transcription has been shown to be mediated by STAT1alpha dimers (p91/p84) which, after nuclear translocation, bind to GAS elements present in the promoter of IFN-gamma responsive genes. Electrophoresis mobility shift assay (EMSA) with both STAT1 consensus and CD40 mGAS probes showed that Trapidil did not affect the DNA binding ability of STAT1 dimers. STAT1 dimerization and activation are conferred by upstream phosphorylation of two amino acid residues of the STAT1 protein. The subsequent studies on these two potential STAT1 phosphorylation sites (Tyr701, Ser727) revealed that Trapidil attenuated IFN-gamma-induced Ser727 but not Tyr701 phosphorylation. The inhibition of CD40 transcription by Trapidil could at least partially owing to the impaired Ser727 phosphorylation of STAT1, since IFN-gamma failed to trigger CD40 expression in U3A S727A cells, a cell line displaying a point mutation at the Ser727 site. Collectively, our results indicate that phosphorylation of STAT1 at the Ser727 site enhances CD40 transcription and that Trapidil might be used as a selective inhibitor that could differentially modulate STAT1 target genes.

CD40 Antigens↗

PubMed2004

HI44a, an anti-CD44 monoclonal antibody, induces differentiation and apoptosis of human acute myeloid leukemia cells.

CD44 is a cell surface antigen that expresses on leukemia blasts from most acute myeloid leukemia (AML) patients. It has been reported that ligation of CD44 with some specific anti-CD44 monoclonal antibodies can reverse the differentiation blockage of leukemia cell lines. In this study, the differentiation and apoptosis-inducing effects of HI44a, another anti-CD44 monoclonal antibody (IgG2a), were investigated on leukemia cells obtained from 31 patients with AML-M2, AML-M3, AML-M4 or AML-M5. When the AML cells were treated with HI44a, the percentage of nitroblue tetrazolium (NBT)+ cells was significantly increased. The expression of CD11b, CD14 and CD15 on treated AML cells was also increased compared to control AML cells. In addition, HI44a was found to induce apoptosis of leukemia cells, as evidenced by an annexin-V assay. The mean percentage of apoptotic cells in HI44a-treated AML cells was significantly increased compared to that in control AML cells. Moreover, the level of c-myc transcript expression on AML cells was found to be obviously decreased in all detected patients. These results indicate that HI44a effectively induces both differentiation and apoptosis of AML cells and suggest that this activity of the anti-CD44 antibody may be associated with its inhibitory effect on c-myc transcript expression.

Acute Disease↗

PubMed2004

Genotypes of Cryptosporidium species infecting fur-bearing mammals differ from those of species infecting humans.

Of 471 specimens examined from foxes, raccoons, muskrats, otters, and beavers living in wetlands adjacent to the Chesapeake Bay, 36 were positive for five types of Cryptosporidium, including the C. canis dog and fox genotypes, Cryptosporidium muskrat genotypes I and II, and Cryptosporidium skunk genotype. Thus, fur-bearing mammals in watersheds excreted host-adapted Cryptosporidium oocysts that are not known to be of significant public health importance.

Animals↗

PubMed2004

Genetic diversity of Cryptosporidium spp. in captive reptiles.

The genetic diversity of Cryptosporidium in reptiles was analyzed by PCR-restriction fragment length polymorphism and sequence analysis of the small subunit rRNA gene. A total of 123 samples were analyzed, of which 48 snake samples, 24 lizard samples, and 3 tortoise samples were positive for Cryptosporidium: Nine different types of Cryptosporidium were found, including Cryptosporidium serpentis, Cryptosporidium desert monitor genotype, Cryptosporidium muris, Cryptosporidium parvum bovine and mouse genotypes, one C. serpentis-like parasite in a lizard, two new Cryptosporidium spp. in snakes, and one new Cryptosporidium sp. in tortoises. C. serpentis and the desert monitor genotype were the most common parasites and were found in both snakes and lizards, whereas the C. muris and C. parvum parasites detected were probably the result of ingestion of infected rodents. Sequence and biologic characterizations indicated that the desert monitor genotype was Cryptosporidium saurophilum. Two host-adapted C. serpentis genotypes were found in snakes and lizards.

Animals↗

PubMed2004

Host-adapted Cryptosporidium spp. in Canada geese (Branta canadensis).

The prevalence and distribution of Cryptosporidium spp. in the fecal droppings of the free-living waterfowl Canada geese were examined at 13 sites in Ohio and Illinois. On the basis of the analysis of the small-subunit rRNA gene by PCR, followed by restriction fragment length polymorphism analysis and DNA sequencing, 49 (23.4%) of 209 fecal specimens collected from 10 sites (76.9%) were positive for Cryptosporidium spp. The following five Cryptosporidium species and genotypes were identified: Cryptosporidium goose genotype I (in 36 specimens), Cryptosporidium goose genotype II (in 9 specimens), Cryptosporidium duck genotype (in 1 specimen), Cryptosporidium parvum (in 4 specimens), and C. hominis (in 2 specimens). Cryptosporidium goose genotype I was the most prevalent parasite and was found at all five Cryptosporidium-positive sites in Ohio and at four of five positive sites in Illinois, followed by Cryptosporidium goose genotype II, which was found at two of five positive sites in Ohio and at four of five positive sites in Illinois. Cryptosporidium goose genotype II was detected for the first time, and it is phylogenetically related to goose genotype I and the duck genotype. All three genotypes have not so far been reported in humans, and their pathogenicity in geese has not been determined. Only 10.2% of the Cryptosporidium-positive specimens had C. parvum and C. hominis. The results of this study indicate that Canada geese might only serve as accidental carriers of cryptosporidia infectious to humans and probably play a minor role in the animal-to-human transmission cycle of the pathogen.

Adaptation, Physiological↗

PubMed2004

Fatal Naegleria fowleri meningoencephalitis, Italy.

We report the first case of primary amebic meningoencephalitis in Italy, in a 9-year-old boy. Clinical course was fulminant, and diagnosis was made by identifying amebas in stained brain sections and by indirect immunofluorescence analysis. Naegleria fowleri was characterized as genotype I on the basis of polymerase chain reaction test results.

Amebiasis↗

PubMed2004

[The relationship between the variants in 5' upstream core promoter A(-6)G and A(-20)C of angiotensinogen gene and essential hypertension in Kazakans of Xinjiang].

OBJECTIVE: To investigate whether the variants A(-6)G and A(-20)C of angiotensinogen (AGT) gene are involved in the pathogenesis of essential hypertension in Kazakans. METHODS: T his case control study recruited 125 subjects with hypertension and 74 normotensive subjects from Kazakans of Xinjiang. Genomic DNA from leukocytes was analyzed for genetic variants A(-6)G and A(-20)C in 5' upstream core promoter of AGT gene by polymerase chain reaction (PCR), single strand conformation polymorphism (SSCP), restriction fragment length polymorphism (RFLP) and automatic sequencing. RESULTS: (1)There were only A(-6)G and A(-20)C variants in the -164 to +73 region of Kazakans' AGT gene. (2) The distributions of genotypes AA, AG, GG at locus -6 of AGT gene showed significant difference between the hypertensive group (0.39, 0.45, 0.16) and the normotensive group (0.49, 0.49, 0.02; Chi2=8.56, P=0.014). There were evident differences in the frequencies of the -6A and the -6G allele of the two groups (0.62, 0.38 and 0.73, 0.27; Chi2=5.35, P=0.021). (3) No significant difference was observed in the distribution of genotypes AA, AC, CC at locus -20 of AGT gene between the hypertensive group (0.69, 0.26, 0.05) and the normotensive group (0.65, 0.32, 0.03; Chi2=2.42, P=0.30). There was no distinct difference in the frequencies of the -20A allele and the -20C allele of the two groups (0.82, 0.18 and 0.82, 0.18; Chi2=0, P=0.99). (4) No significant difference was found at the levels of systolic and diastolic blood pressure between the groups corresponding to genotypes at the loci -6 and -20 of AGT gene. CONCLUSION: The results suggest that the polymorphism of A(-6)G in 5' upstream core promoter of the AGT gene may be involved in the pathogenesis of essential hypertension in Kazakans, while the A(-20)C variant may not play an important role in the etiology of essential hypertension in Kazakans.

5' Flanking Region↗

PubMed2004

[A study on risk factors among 125 type 2 diabetes mellitus with familial tendency].

OBJECTIVE: To study the risk factors regarding heredity and environment in familial incident type 2 diabetes mellitus (DM). METHODS: To compare the difference of environmental risk factors between type 2 DM, impaired glucose tolerance (IGT) and normal persons through study on familial information and environmental risk factors in 125 familial incident type 2 DM in-patients and out-patients from 1999 to 2001. Falconer was used to estimate heritability. Penrose was used to study the heredity damagers by polygene analysis. RESULTS: There was a significant constituent ratio diversity (P < 0.01) in triglyceride, body mass index, waist to hip ratio, hypertension history and physical activities history among 3 groups, while no significant diversity in blood lipids and history of coronary heart disease. 83.42% +/- 5.84% heritability of type 2 DM in 125 familial predigree indicated that dominant major gene might exist in these familiar pedigrees. Analysis of polygene in these groups showed type 2 DM might conform to the model of polygene heredity. CONCLUSION: This study suggested that type 2 DM had significant heritability and genetic heterogeneity, which generally appeared to be a disease of multi-factorial inheritance. Environmental risk factors, genetic factors and their interactions were due to type 2 DM.

Adult↗

PubMed2004

[Construction and immune potency of recombinant adenovirus containing codon-modified HIV-1 gp120].

BACKGROUND: To construct replication-deficient recombinant adenovirus expressing wild and codon-modified HIV-1 gp120. METHODS: The viral codons were changed to the codon usage of highly expressed mammal gene, the resulting modified gp120 gene was synthesized. The wild and modified gp120 genes were cloned into shuttle vector pShuttle-CMV respectively, and then the constructed plasmids containing gp120 gene was cotransformed with the backbone vector pADeasy-1 into E.coli BJ5183. Transfection of the recombinant AdEasy plasmid into 293 cells was performed to obtain recombinant adenoviruses. The mice were immunized with the recombinant adenoviruses. Their immunogenicity was evaluated by testing antibody and CTL levels of immunized mice. RESULTS: Two strains of recombinant adenovirus expressing wild and codon-modified HIV-1 gp120 were obtained. The protein expressing level of the recombinant adenoviruses containing modified genes was much higher than that containing wild genes. The mice immunized with recombinant adenoviruses elicited HIV-1 specific antibody and CTL response. The rAd-mod gp120 group was better than the rAd-wt gp120 group. CONCLUSION: Replication-deficient recombinant adenovirus expressing HIV-1 gp120 can elicit HIV-1 specific humoral and cellular response, the codon-modified recombinant virus was more efficient than the native.

AIDS Vaccines↗

PubMed2004

[Immortalization of human embryonic cervical epithelial cells induced by E6, E7 genes of human papillomavirus 16].

OBJECTIVE: To establish an immortalized cell line derived from the embryonic cervical epithelium by infection with the recombinant adeno-associated virus (rAAV) containing human papillomavirus (HPV)16 E6, E7, and to study the biological features of cervical cancer cell line. METHODS: Human embryonic cervical tissues were cultured in keratinocyte free serum (K-FS) medium and infected with rAAV containing HPV16 E6, E7. Morphological features and growth rate were examined by light, electronic and fluorescence microscopies. The fragments of E6, E7 were detected by polymerase chain reaction (PCR) and laser confocal microscopy. The biological characteristics of human cervical epithelium were observed by soft agar culture, scid mice inoculation and chromosome analysis. Cell proliferative dynamics was plotted by flow cytometry. RESULTS: After a long-term culture, the phenotype kept the characteristics of primary epithelial cells. They showed monolayer, anchorage-dependent and attachment-inhibited growth without forming colonies in soft agar culture. They were non-oncogenic when inoculated into scid mice. The tonofilament expression in the cervical cancer cells was inspected by electronic microscopy, demonstrating that the cells were squamous epithelium in origin. The cell line contained HPV16 E6, E7 genes by PCR and laser confocal detection. Chromosome analysis disclosed that the karyotype was diploid or polyploid. The 11th chromosome was assumed to be the integration site by rAAV containing HPV16 E6, E7. CONCLUSIONS: Establishment of the immortalized cervical epithelial cell line by infection with rAAV containing HPV16 E6, E7, supports that HPV16 E6, E7 may be the primary etiology of cervical cancer. It will facilitate further research on the etiology and pathogenesis of cervical cancer.

Animals↗

PubMed2004

[Control of chironomids in water by immobilized Bacillus thuringiensis var. israelensis de Barjac].

A strain from Bacillus thuringiensis var. israelensis de Barjac (B. t. i), having a fatal toxicity to chironomids, was immobilized in the PVA-H3BO3 gel beads confected with a bit of sodium alginate and activated carbon. The result showed that optimal weight ratios were 10% PVA, 1% sodium alginate and 20% activated carbon, respectively. When 4% calcium chloride saturated boric acid solution (pH=6.7) was used as gelatin agent for gelating 24 h, the produced gel beads had good performance in mechanical strength. This method is proved to be simple and cheap. The toxicity of the beads to chironomids is high and the release is slow.

Animals↗

PubMed2004

[Study on the relationship between sulfonylurea receptor 1 gene polymorphism and type 2 diabetes mellitus].

To study whether the 3c/t polymorphism of the sulfonylurea receptor 1 (SUR1) gene exon16 increased the risk of type 2 diabetes mellitus in type 2 diabetes mellitus pedigrees in Han population in south area of China. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method was used in 46 type 2 diabetes mellitus pedigrees. The polymorphism in SUR1 was tested and analyzed by Mantel-Haenszel chi(2) test. Frequencies of SUR1-3c/t polymorphism had no significant difference between type 2 diabetes mellitus and normal relatives (genotypes chi(2)=3.224, P=0.199; frequency of allele chi(2)=1.250, P=0.264). In all subjects, type 2 diabetes mellitus and normal relatives, SUR1-3c/t genotypes were listed (cc: 29.3%, 30.2%, 28.3%; ct: 50.7%, 53.8%, 47.2%; tt: 20%, 16.0%, 24.5% respectively). The frequencies of c were 54.7%, 57.1% and 51.9% respectively. The frequency of c is lower than Han population in northern China. The results show that SUR1 exon16-3c/t polymorphism is not associated with type 2 diabetes mellitus in the population.

ATP-Binding Cassette Transporters↗