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Ping Zhao

Publications and source records attributed to Ping Zhao.

At least 109 records · Page 6Linked to original sources
PubMed2004

[Analysis on factors related to X-ray outcomes in 93 SARS patients].

OBJECTIVE: To study the related factors of the X-ray outcomes in recovered SARS patients. METHODS: The X-ray results of 93 patients with SARS were studied retrospectively. The possible related factors analyzed were age, sex, body temperature at onset, range of the lesion, glucocorticoid administration time. The data were analyzed by chi square test. RESULTS: Among all the patients with abnormal X-ray result, 19 were male (54.29%), 16 (45.71%) were female, P > 0.01; 7 (58.33%) were above the age of 45; 28 (34.57%) were below the age of 45, P > 0.01; hyperpyrexia (>/= 39), 26 (50.00%), below 39, 9 (21.95%); multiple-lesion, 22 (52.38%), mono-lesion, 13 (25.49%), P < 0.01; glucocorticoid administration time within 5 days, 22 (38.60%) after 5 days, 12 (33.33%), P > 0.01; within 7 days, 21 (30.00%), after 7 days, 14 (60.87%), P < 0.01. CONCLUSION: The X-ray results of SARS were closely related to the severity of the disease (hyperpyrexia and bilateral lung field lesion). There was no significant correlation between X-ray result and the age or sex of the patients. Early use of glucocorticoid (within 5 days after onset), had no remarkable influence on the X-ray result. It was noted, however, the incidence of residual lesion in lung obviously increased if glucocorticoid was administered after 7 days of onset.

Adult↗
PubMed2003

Characterization of leachianone G 2"-dimethylallyltransferase, a novel prenyl side-chain elongation enzyme for the formation of the lavandulyl group of sophoraflavanone G in Sophora flavescens Ait. cell suspension cultures.

Leachianone G (LG) 2"-dimethylallyltransferase, a novel prenyl side-chain elongation enzyme, was identified in Sophora flavescens Ait. cultured cells. The enzyme transfers a dimethylallyl group to the 2" position of another dimethylallyl group attached at position 8 of LG to form sophoraflavanone G, a branched monoterpenoid-conjugated flavanone characteristic to this plant. This membrane-bound dimethylallyltransferase required Mg2+ (optimum concentration was 10 mm) for the reaction and had an optimum pH of 8.8. It utilized dimethylallyl diphosphate as the sole prenyl donor, and the 2'-hydroxy function in LG was indispensable to the activity. The apparent Km values for dimethylallyl diphosphate and LG were 59 and 2.3 microm, respectively. Subcellular localization of three enzymes that participated in the formation of the lavandulyl group was also investigated by sucrose density gradient centrifugation. Two prenyltransferases, naringenin 8-dimethylallyltransferase and LG 2"-dimethylallyltransferase, were localized in the plastids, whereas 8-dimethylallylnaringenin 2'-hydroxylase, which catalyzes the crucial step in the lavandulyl-group formation, was associated with the endoplasmic reticulum. These results suggest the close cooperation between the plastids and the endoplasmic reticulum in the formation of lavandulyl groups.

Cells, Cultured↗
PubMed2003

Efficient production and capture of 8-prenylnaringenin and leachianone G-biosynthetic intermediates of sophoraflavanone G--by the addition of cork tissue to cell suspension cultures of Sophora flavescens.

It has previously been demonstrated that the addition of cork tissue to cell suspension cultures of Sophora flavescens stimulates the production of sophoraflavanone G, most of which has been recovered from the added cork tissue. In the present study, it was found that two precursors of sophoraflavanone G, 8-prenylnaringenin (sophoraflavanone B) and leachianone G, both of which have never been detected either in cultured cells or in the original plants, also accumulated in the added cork tissue. Thirteen minor flavonoids including three prenylated flavonoids, in addition to 8-prenylnaringenin and leachianone G, were isolated from the cork tissue co-incubated with S. flavescens cells. The new compounds flavescenones A, B and C, were determined to be (3R)-5, 7, 2'-trihydroxy-6-gamma, gamma-dimethylallyl-4', 5'-methylenedioxyisoflavanone; 5, 7, 2'-trihydroxy-6-gamma, gamma-dimethylallyl-4', 5'-methylenedioxyisoflavone and 2-[2',4'-dihydroxy-3'-(gamma-hydroxymethyl-gamma-methylallyl)phenyl]-5,6-methylenedioxybenzofuran, respectively, by means of spectroscopic analyses that included 2D-NMR techniques.

Acetates↗
PubMed2003

Phage display selection on whole cells yields a small peptide specific for HCV receptor human CD81.

The human CD81 (hCD81), the most recently proposed receptor of hepatitis C virus (HCV), can especifically bind to HCV envelope glycoprotein 2 (E2). In this study, hCD81-expressing murine NIH/3T3 cells were used to select hCD81-binding peptides from a phage displayed nonapeptide library (PVIII9aaCys). Eighteen of the 75 clones selected from the library showed specific binding to the hCD81-expressing NIH/3T3 cells by enzyme linked immunosorbent assay (ELISA) and competitive inhibition test. Twelve out of the 18 clones shared the amino acid motif SPQYWTGPA. Sequence comparison of the motif showed no amino acid homology with the native HCV E2. The motif-containing phages could competitively inhibit the ability of HCV E2 binding to native hCD81-expressing MOLT-4 cells, and induce HCV E2 specific immune response in vivo. These results suggest that the selected motif SPQYWTGPA should be a mimotope of HCV E2 to bind to hCD81 molecules. Our findings cast new light on developing HCV receptor antagonists.

Amino Acid Motifs↗
PubMed2003

Explanation of vegetation succession in subtropical southern China based on ecophysiological characteristics of plant species.

A stomatal conductance model and a photosynthesis model were applied to field measurements of transpiration and photosynthesis of seven tree species growing in subtropical southern China. Parameter values of drought resistance and tolerance and biochemical assimilation capacity were obtained by means of nonlinear statistical regression, and were used to quantify species succession. The analysis indicated that the models adequately described the ecophysiological behavior of the trees under various environmental conditions. We found a general pattern of decreased drought resistance and tolerance, but increased biochemical assimilation capacity from pines to heliophilus broadleaf trees to mesophilus broadleaf trees. Succession was explained on the basis of these physiological characteristics together with positive feedbacks caused by changes in soil physical properties. The ecophysiological explanation of succession implies that: (1) fitness of a species for a particular succession stage at a particular location can be measured by stomatal behavior and biochemical assimilation capacity under local climate and soil conditions; (2) selection of species for a particular location at a particular succession stage can be guided by the parameter values provided in this study; and (3) succession may be accelerated by selecting trees with large root systems and large soil-root conductances that facilitate soil hydraulic redistribution of water.

China↗
PubMed2003

Cocirculation and evolution of two lineages of influenza B viruses in europe and Israel in the 2001-2002 season.

Forty-nine influenza B virus isolates collected in Belgium, Finland, Spain, and Israel during the 2001-2002 winter season were categorized into either of two lineages, B/Yamagata/16/88 or B/Victoria/2/87, based on the phylogenetic studies of HA1 sequences. The data trace the geographic spread of B/Victoria/2/87-like viruses and support the emergence of B/Hong Kong/1351/02-like viruses, possibly due to selective advantages of reassortment.

Amino Acid Sequence↗
PubMed2003

Pathogenicity of enterohemorrhagic Escherichia coli in neonatal calves and evaluation of fecal shedding by treatment with probiotic Escherichia coli.

The pathogenicity and fecal shedding of enterohemorrhagic Escherichia coli (EHEC) O26:H11, O111:NM, and O157:H7 were compared in calves (< 1 week of age) with or without prior treatment with probiotic bacteria (competitive exclusion E. coli). Three groups of 12 to 14 calves were used for these treatments. Half of the calves in each group were perorally administered 10(10) CFU of probiotic bacteria per calf, and, 2 days thereafter, 10(8) CFU of a five-strain mixture with one of the three EHEC serotypes per calf were administered to each calf. None of the EHEC serotypes caused clinical disease,and neither gross nor microscopic lesions attributable to EHEC were detected in control or probiotic-treated calves at necropsy. In calves administered E. coli O157:H7, fecal shedding was greatly reduced (> 6 log10 CFU/g) by 8 days after administration, and there was no significant difference (P > 0.05) in fecal shedding of E. coli O157:H7 between probiotic-treated and untreated control groups at that time. In contrast, control calves perorally administered E. coil of serotypes O111:NM or O26:H11 continued to shed substantial populations (10(2.1) to 10(6) CFU/g of feces and 10(2.5) to 10(4.9) CFU/g of feces, respectively) throughout 7 days postadministration of EHEC. In both groups administered either E. coli O111:NM or O26:H11, significantly less (P < 0.05) EHEC was isolated from feces at 7 days postadministration of EHEC and at necropsy from theprobiotic-treated group than from the untreated control group. Overall, neonatal calves shed in the feces from 1 to 7 days following peroral administration of EHEC greater populations of E. coli O111:NM and O26:H111 than E. coli O157:H7. In addition, treatment of calves with probiotic E. coli reduced fecal shedding of E. coli O111:NM and O26:H11 in most calves.

Animals↗
PubMed2003

Fecal shedding of enterohemorrhagic Escherichia coli in weaned calves following treatment with probiotic Escherichia coli.

The fecal shedding and pathogenicity of enterohemorrhagic E. coli (EHEC) O26:H11, EHEC O111:NM, and EHEC O157:H7 in weaned calves (8 to 10 weeks of age) were compared with and without treatment with a three-strain mixture of probiotic bacteria (competitive-exclusion E. coli). Three groups of 12 calves were each perorally given a five-strain mixture of one of the EHEC serotypes (10(10) CFU of total bacteria per calf). Seventy-two hours later, six calves from each group were each administered 10(10) CFU of probiotic bacteria. None of the EHEC serotypes caused significant clinical disease, although a few calves developed mild transient diarrhea or pyrexia. Gross or microscopic lesions attributable to EHEC were not detected in control or probiotic-treated calves at necropsy. For probiotic-treated calves given E. coli O157:H7 and for probiotic-treated calves given E. coli O111:NM, fecal shedding was reduced compared with that for untreated calves. For the probiotic-treated calves given E. coli O157:H7, the reductions in fecal shedding on days 8, 12, 14, 16, 20, 22, 28, and 30 after peroral administration were statistically significant (P<0.05). For probiotic-treated calves given E. coli O111:NM, there were statistically significant reductions (P<0.05) in fecal shedding on days 6, 8, 10, and 12. In contrast, there was no reduction in fecal shedding for calves administered E. coli O26:H11 and treated with the probiotic bacteria. In fact, calves in both the treated and the nontreated groups continued to shed large populations of E. coli O26:H11 throughout the 32-day trial. At necropsy, E. coli O157:H7 was isolated from five of six untreated calves and from only two of six probiotic-treated calves. E. coli O111:NM was isolated from four of six untreated calves at necropsy and from two of six probiotic-treated calves. However, E. coli O26:H11 was isolated from five of six untreated calves and from all six probiotic-treated calves. The results obtained in this study indicate that probiotic E. coli substantially reduced or eliminated fecal shedding of E. coli O157:H7 and E. coli O111:NM 8 to 30 days and 6 to 12 days after the administration of the probiotic culture, respectively, and reduced the persistence of E. coli O157:H7 in the gastrointestinal tract at necropsy (31 to 33 days after the administration of the probiotic culture). The probiotic E. coli did not reduce fecal shedding or gastrointestinal persistence of E. coli O26:H11.

Animals↗
PubMed2003

[Enhancement by an in vivo-activated promoter of immunogenicity of recombinant attenuated Salmonella typhimurium expressing hepatitis C virus core antigen].

The promoter of phoP-activated gene C (P(pagC)) of Salmonella typhimurium was cloned and used as transcriptionally regulating element for a plasmid that expresses hepatitis C virus core antigen. The resultant plasmid was transformed into attenuated Salmonella typhimurium SL7207 and its expression activity in vitro was determined. Mg(2+) inhibited the recombinant bacteria to express HCV core antigen in a dose-dependent manner. This recombinant strain, and another bacterial strain that constitutively expresses HCV core antigen were orally inoculated BALB/c mice respectively. The stability of the plasmid in the bacteria and the immune responses was analyzed. The results showed that the in vivo activated P(pagC) promoter could stabilize the plasmid in the bacteria and enhance the humoral and cellular immune responses greatly, showing a novel way to produce effective, cheap oral vaccine against hepatitis C.

Administration, Oral↗
PubMed2003

[Peritoneal lavage cytology in 66 patients with gastric carcinoma].

OBJECTIVE: To evaluate the clinical and prognostic value of peritoneal lavage cytology (PLC) in detecting free cancer cells (FCC). METHODS: PLC of 66 gastric cancer patients being operated was prospectively analyzed to assess the prognostic significance of positive cytological finding and its relation with serosal invasion, lymph node metastasis and stage classification. RESULTS: The overall positive rate of cytology was 36.4% (24/66). These was a closely relation between positive cytology results and serosal invasion (P = 0.025), abdominal lymph node involvement (P < 0.005) and stage classification. Peritoneal recurrence in patients with positive cytological findings was significantly higher than that with negative results (P = 0.006 7). CONCLUSION: Micrometastasis to the abdominal cavity, formed by free cancer cells exfoliated from the tumor, are significantly responsible for peritoneal dissemination. Serosal invasion and metastatic nodes have greater risk for positive cytology and implies poor prognosis. Peritoneal lavage cytology, if practiced in all gastric cancer patients being operated, can predict the operative effect and prognosis, increase the accuracy of clinical stage and provide information for further adjuvant therapy.

Adult↗
PubMed2003

[Establishment of a SCID mouse model for synergistic anti-tumor effect of human IL-12 and B7-1].

Human IL-12(hIL-12) has weak effect on mouse immunity cells, so the practical animal model is not available for the study of hIL-12 anti-tumor activity. In this work, the improved Winn assay was applied to evaluate the synergistic anti-tumor effects of hIL-12 and human costimulatory molecule B7-1(hB7-1) on human tumor in HuPBL-SCID mouse model. Three gene transferring solutions hIL-12, hB7-1 and their mixture(1:1) were prepared using the nonliposome transgene reagent and the expressing vectors, and hIL-12, hB7-1 or their mixture were transferred into tumor cell A375 respectively. Then A375 were co-injected into SCID mice with HuPBL, and rhIL-2 were injected i.p. as an anti-tumor agitator. On the other hand, LoVo and SPC tumor cells were also used to test the inhibitory effect of the mixture of hIL-12 and hB7-1. The anti-tumor effect of transferred genes was estimated by detecting tumor inhibition rate. Furthermore, the histochemical change of A375 implanting tumor tissue was also observed. Results showed that, to A375, the tumor inhibition rate of hIL-12, hB7-1, or their mixture were 74.06%, 66.98%, and 93.40%, respectively (P<0.01); and the mixture showed a good synergistic effect according to the Webb s fraction multiplication law. The tumor inhibition rate of the mixture in LoVo and SPC implanted mice were 98.37% and 97.39% respectively, also showing a good synergistic effect. Histochemical study in A375 implanted mice showed that in gene transfected mice, tumor cells were greatly inhibited and fully intruded by HuPBL cells; while in control group, tumor cells grew very well and HuPBL showed a conglomeration. At last, the human IgG and T cells in PBL of HuPBL-SCID mice were higher than non-HuPBL-SCID mice implanted A375; which showed that HuPBL-SCID mice could be applied for the evaluation of the anti-tumor effect of human IL-12 and B7-1. All data indicated that the combination of hIL-12 and hB7-1 gene might be a promising approach for in vivo cancer therapy.

Animals↗
PubMed2003

[Photosynthesis and free radical yield of Litchi chinensis leaves under increased CO2 partial pressure in atmosphere].

The maximum photosynthetic rate of litchi saplings leaves grown under a CO2 partial pressure of 77 +/- 5 Pa was 23% lower than that of 39.3 Pa, and slight decreases in respiration rate in light and CO2 compensation point excluding of respiration in light were observed. The maximum rates of carboxylation (Vcmax) and photosynthetic electron transport (Jmax) were decreased in saplings grown under 77 +/- 5 Pa CO2 partial pressure. It may suggest that there was a lower energy level of photosystem I(PSI) in the saplings leaves under 77 +/- 5 Pa CO2 partial pressure, and free radical yield decreased by 39% in the saplings under 77 +/- 5 Pa CO2, as comparied with that under atmospheric CO2. The percentage of infection by Peronophythora litchi increased from 1.8% under atmospheric CO2 to 9.5% under enriched CO2. It may mean that the decreasing photosynthetic and respiration metabolism would make it lower the production of O2-., and leaves were infected by P. litchi more easily. The controlling of the popularization of P. litchi for litchi plantation must be paid wide attention, as air CO2 partial pressure will increase continuously.

Carbon Dioxide↗
PubMed2003

Antigen-expressed recombinant Salmonella typhimurium driven by an in vivo-activated promoter is capable of inducing cellular immune response in transgenic mice.

To explore the approaches and mechanisms for reversing the immune tolerance in transgenic mouse, and the pathogenicity of hepatitis G virus (HGV), the promoter of phoP-activated gene (P(pagC)) of Salmonella typhimurium was used as a transcriptionally regulating element to construct an attenuated S. typhimurium expressing HGV NS3. The recombinant S. typhimurium was orally administered to HGV transgenic mice. As the results, HGV antigen in serum and liver as well as HGV mRNA in liver were decreased significantly, although the serum anti-HGV NS3 remained undetectable as the control transgenic mice. The spleen cell proliferation, in vitro HGV NS3 specific CTL, and IFN-gamma assays with the primed cultured splenocytes indicated the induction of Th1 immune responses in those administered transgenic mice. Adoptive transfer of fractionated primed spleen cells to the transgenic mice showed that T lymphocytes were responsible for, maybe through IFN-gamma, the down-regulation of HGV mRNA transcription. Histological examination found no significant inflammatory changes in liver of the transgenic mice. These findings suggested that the oral inoculation of the HGV NS3-expressed attenuated S. typhimurium driven by an in vivo-activated promoter should be a simple and effective approach for potential treatment of chronic viral infection.

Adoptive Transfer↗
PubMed2003

[Application of proteomic approach for solid tumor marker discovery].

In the post-genome era, the major mission of biology is to understand the functions of genome. To well know the whole book of genes, the proteins coded by different genes have to be studied more deeply since they are the final representatives of the specific genes. Proteomics is the key issue in the bioscience research. Using the two dimensional electrophoresis technique, the total proteins of tumor cells or tissues can be profiled first by their molecular weight and isoelectric points, after that, the specific interested proteins can be identified via mass spectrometry analysis combining with database searching. Cancer proteomics is a main part of the proteomics, by which we can understand the protein profiles during the different stages of the tumorigenesis and it brought a new hope for discovery of the tumor-specific biomarkers. Recently using proteomic tools with the laser capture microdissection (LCM) technique, more achievements have been made and many promising candidates of tumor-markers have been identified even most of them have not affirmed yet. This article will give a brief review about that.

Biomarkers, Tumor↗
PubMed2003

[Scientometrics and bibliometrics of biomedical engineering periodicals and papers].

This investigation was made to reveal the current status, research trend and research level of biomedical engineering in Chinese mainland by means of scientometrics and to assess the quality of the four domestic publications by bibliometrics. We identified all articles of four related publications by searching Chinese and foreign databases from 1997 to 2001. All articles collected or cited by these databases were searched and statistically analyzed for finding out the relevant distributions, including databases, years, authors, institutions, subject headings and subheadings. The source of sustentation funds and the related articles were analyzed too. The results showed that two journals were cited by two foreign databases and five Chinese databases simultaneously. The output of Journal of Biomedical Engineering was the highest. Its quantity of original papers cited by EI, CA and the totality of papers sponsored by funds were higher than those of the others, but the quantity and percentage per year of biomedical articles cited by EI were decreased in all. Inland core authors and institutions had come into being in the field of biomedical engineering. Their research topics were mainly concentrated on ten subject headings which included biocompatible materials, computer-assisted signal processing, electrocardiography, computer-assisted image processing, biomechanics, algorithms, electroencephalography, automatic data processing, mechanical stress, hemodynamics, mathematical computing, microcomputers, theoretical models, etc. The main subheadings were concentrated on instrumentation, physiopathology, diagnosis, therapy, ultrasonography, physiology, analysis, surgery, pathology, method, etc.

Authorship↗