PubMed Health⌕ Search

Biomedical subjects

Ping Zhao

Publications and source records attributed to Ping Zhao.

At least 127 records · Page 7Linked to original sources
PubMed2003

[Evaluation of antibacterial activity of amoxycillin sodium and clavulanate potassium and the pharmacoeconomics in the therapy of acute respiratory infection].

OBJECTIVE: To explore the antibacterial activity of amoxycillin sodium and clavulanate potassium (trade name: Anqi) in vitro and the pharmacoeconomics in the therapy of acute respiratory infection. METHODS: Minimal inhibition concentration (MIC), minimal bactericidal concentration (MBC) and bactericidal curve of amoxycillin sodium and clavulanate potassium against common pathogens were determined and compared with some other same kind of antibiotics without beta-Lactamase inhibitor. Eighty cases diagnosed as respiratory infection were randomly divided into 4 groups: group 1 was treated with i.v. Anqi; group 2 was treated with i.v. Anqi and oral consecutive strategy; group 3 was treated with iv ampicillin and sulbactam; group 4 was treated with i.v. cefuroxime. The clinical therapeutic effects were observed and cost-effectiveness analyzed. RESULTS: In terms of MIC, MBC and bactericidal curve of 135 bacterial strains, Anqi was superior to the other same-kind antibiotics without beta-lactamase inhibitor, this effect was especially obvious on Klebsiella pneumoniae and Escherichia coli which can produce extended spectrum beta-lactamases (ESBLs). The cost-effectiveness of the consecutive therapy group was the best. CONCLUSION: Anqi has a wide antimicrobial spectrum and strong effect on the bacteria producing ESBLs, the consecutive therapy strategy should be clinically recommended.

Amoxicillin↗
PubMed2003

[Advances in plant ecophysiological studies on re-vegetation of degraded ecosystem].

Natural force and human intervention lead to many local, regional, and sometimes global changes in plant community patterns. Regardless of the cause and intensity of these changes, ecosystem can recover most of their attributes through natural succession, or can be repaired by human assistance. The essentiality of restoration of degraded ecosystem is community succession, a process during which an ecosystem evolves from primary stage to advanced stage, and its structure and function change from simple to complex plant. Ecophysiological study could explain some macroscopical phenomena of the ecology of re-vegetation of degraded ecosystem, and provide a scientific base for assembling pioneering plant community. The advances in plant ecophysiological study on re-vegetation of degraded ecosystems were reviewed in this paper.

Biomass↗
PubMed2003

[Identification of HCV antigen epitopes from a random 15-peptide library by anti-HCV polycloral antibody].

AIM: To analyze epitope recognized by anti-HCV antibodies; patients suffered from hepatitis C. METHODS: Anti-HCV Abs were purified from the patients serum through an affinity chromatography column which was prepared with sepharose 4B coupled with protein A. These Abs were used for biopanning of a phage-displayed random 15-peptide library. RESULTS: After 3 rounds of biopanning, the ratio of output to input increased to 3.3 x 10(3) and the false positive rate reduced to 0.2%, suggesting that the enrichment was effective. After the third round of biopanning, sixteen clones were selected to conduct binding test to Abs from the patients and normal person's sera. Nine of them were proved to react specifically to the sera from the patients. From the deduced insert sequence in the coat protein VIII, the core sequence of WPWS was found in 8 clones. The positive phage clones could react to different patients' and not react to normal person's sera. CONCLUSION: These findings indicate that WPWS motif in the short peptide may mimic the HCV epitope recognized by anti-HCV Abs.

Amino Acid Sequence↗
PubMed2003

Neutralizing monoclonal antibody against anthrax lethal factor inhibits intoxication in a mouse model.

Anthrax toxin is the dominant virulence factor of Bacillus anthracis; drugs blocking its action could therefore have therapeutic benefit. We report here the production of a neutralizing monoclonal antibody (mAb) against anthrax lethal factor (LF) and the inhibition by the antibody of anthrax lethal toxin (LeTx) formation. The anti-LF monoclonal antibody LF8 neutralized the LeTx challenge both in vitro with macrophage J774A.1 cells and in vivo in nude mice. Our data suggested that LF8 binds LF at or near the PA binding domain. A set of dodecameric peptides was selected from a phage-displayed peptide library through their specific binding to anti-LF neutralizing mAb LF8. These small peptides compete with LF to bind LF8. Further investigation is undergoing to test the potential application of these peptides to the clinical treatment of anthrax infection by blocking LeTx formation.

Animals↗
PubMed2003

[Enhancement of cellular immune response to DNA vaccine encoding hepatitis C virus core and envelope 2 fusion antigen by murine Fms-like tyrosine kinase 3 ligand].

Hepatitis C virus (HCV) is an important human pathogen that causes chronic liver disease worldwide. It is desirable to develop vaccines to prevent HCV infection, or at least to prevent progression to chronicity. We once constructed an optimized hepatitis C virus core and envelope 2 fusion antigen DNA vaccine, which could induce humoral and cellular immune responses against HCV core and E2 protein in BALB/c mice efficiently. Flt3 (Fms-like tyrosine kinase 3) -ligand has been identified as an important cytokine for the generation of professional antigen-presenting cells, particularly dendritic cells. We reasoned that a DNA vaccine coexpressing the antigen and FL may activate immune responses more effectually. In this study, The influence of FL on this HCV DNA vaccine was evaluated. The cDNA encoding signal peptide and extracellular domain of murine FL was inserted into the plasmid pST-CE2t, and the resulting plasmid pST-CE2t/FL was transfected into COS7 cells. The HCV core and E2 protein were detected by Western blotting, and the soluble murine FL was detected by ELISA. Eight-week-old female BALB/c mice were inoculated intramuscularly with 100 microg pST-CE2t, pST-CE2t/FL or mock vector, respectively, and boosted at the same dosage 3 weeks later. Anti-HCV core and E2 total IgG and isotypes were measured at weeks 1,3,5,7. Splenocyte proliferative response to recombinant HCV core and E2 protrein were detected at week 7. SP2/0 cells expressing HCV core protein were used as target cells for the detection of cytotoxic T lymphocyte (CTL) response. Western blot analysis showed that a protein band with molecular weight about 70 kD from lysate of COS7 cells transfected with plasmid pST-CE2t/FL could be detected by anti-HCV core or E2 monoclonal antibodies, which indicated that pST-CE2t could express glucosylated HCV core and E2 fusion protein. Murine FL could be detected in the culture supernatant of COS7 cells transfected with pST-CE2t/FL. Plasmid pST-CE2t immunized mice developed higher anti-HCV core and E2 IgG seroconversion rates and titers than pST-CE2t/FL group did at different various times, but the IgG2a/IgG1 ratio of anti-HCV E2 protein in pST-CE2t/FL group is much higher than pST-CE2t group. Splenocytes from pST-CE2t or pST-CE2t/FL immunized mice could proliferate with stimulation of HCV core or E2 protein in vitro, although pST-CE2t/FL group showed much stronger response. Splenocytes from mice immunized with pST-CE2t/FL induced 79.03% +/- 9.95% of target cell lysis at the effector/target ratio of 100:1, which was significantly greater than the lysis (62.2% +/- 8.62%) observed in mice immunized with pST-CE2t. Our data demonstrated that the incorporation of FL can preferentially enhance the cellular response to this HCV fusion antigen DNA vaccine. In contrast, HCV specific antibodies were inhibited by FL in vaccinated mice. More and more data supports that recovery from acute HCV infection may depend upon the generation of broad-based cellular immune responses to viral proteins. So, FL may be of potential value as an adjuvant in the development of DNA-based immunization for prophylactic and therapeutic vaccine against HCV infection.

Animals↗
PubMed2003

[Cloning and functional analysis of promoter pagC from attenuated Salmonella typhimurium].

This study describes the cloning and function of promoter pagC (P(pagC)) from Salmonella typhimurium. The expression plasmid containing the in vivo-inducible promoter pagC and HGV-NS3 gene was introduced into the attenuated Salmonella typhimurium SL7207 to investigate the function of P(pagC). The expressed HGV-NS3 protein was detectable by SDS-PAGE and Western blotting in the recombinant bacteria in the presence of low concentration of Mg2+ (<50 mmol/L). When the concentration of Mg2+ reached to 50 mmol/L, the amount of expressed HGV-NS3 was decreased significantly. The recombinant bacteria were multiplied in LB medium containing 50 mmol/L of Mg2+ and used as a DNA vaccine to orally inoculate C57 mice for three times. The results of serum antibodies, T lymphocyte proliferative response and cytotoxic T lymphocyte response of immunized mice showed that the oral vaccine could iuduce strong humoral and cellular immune responses in mice, which indicates that the P(pagC) is a strong in vivo-inducible promoter and can be used in attenuated Salmonella typhimurium to construct an effective oral vaccine.

Animals↗
PubMed2002

[Breast cancer in multiple primary malignant neoplasms, epidemiological and clinical analysis].

OBJECTIVE: To investigate the epidemiological and clinical characteristics of breast cancer associated with multiple primary malignant neoplasmas (MPMNs). METHODS: The data of 519 patients of breast cancer associated with MPMNs admitted to the Cancer Hospital, CAMS and diagnosed by operation and pathology in the period of 1958 to 2001 were studied retrospectively to analyze the morbity, age of onset, sex ratio, predilection site of tumor, and the interval time between sequential tumors. The 519 patients, all female, were divided into four groups: bilateral primary breast cancer (1st group), synchronic Paget's disease (PD) associated with breast cancer in the same breast (2nd group), breast cancer as the first tumor associated with MPMNs (3rd group), and breast cancer as the second or third tumour associated with MPMNs (4th group). RESULTS: The constituent rate of bilateral primary breast cancer, synchronic Paget's disease (PD) associated with breast cancer in the same breast, breast cancer as the first tumor associated with MPMNs, and breast cancer as the second or third primary tumour associated with MPMNs was 3.0%, 0.8%, 3.2%, and 2.5% respectively. The median age of onset was 42.5, 47.3, 51.4, and 51.8 years respectively for the four groups. The mean interval time between the appearance of the first tumor and the appearance of the second tumor was 5.4, 0, 8.6, and 7.6 years in the four groups respectively. The predilection sites of second and third primary cancers in the third group were lung, breast, esophageal, ovary, and large intestine. The predilection sites of first primary cancer in the 4th group were uterus, ovary, large intestine, lung, lymphatic tissue, and esophagus successively. The involvement rate of breast in breast cancer associated with MPMNs was 72.4%. CONCLUSION: (1) Breast is one of the predilection organs of MPMNs. (2) The predilection organs of breast associated with MPMNs are the target organs of female hormone (eg, breast, ovary and uterus) and the organs involved by radiotherapy for breast cancer (eg, lung and esophagus). (3) Early diagnosis and timely and proper treatment have satisfactory effect.

Adult↗
PubMed2002

[Non-functional islet-cell tumor: analysis of 237 cases].

OBJECTIVE: To summarize the clinical aspects of nonfunctional islet-cell tumor (NIT) reported in Chinese periodicals. METHODS: Articles in Chinese on NIT were screened from the Chinese Bio-Medical Database (1981.1 - 1999.10). Data of epidemiology, clinical manifestations, diagnosis, defferential diagnosis, and treatment of NIT were analyzed. RESULTS: 60 articles and 237 cases of NIT were selected. The female to male ratio was 2.9:1. Abdominal mass was the most common clinical symptom. It was difficult for the pre-operative diagnosis of NIT and differentiation from pancreatic tumor or retroperitoneal mass. The malignant rate of NIT was 35%. The five-year survival rate of malignant NIT was 53.1%. CONCLUSION: NIT is rare. It occurs more often in female than in male. The preoperative diagnostic rate is rather low. The prognosis of malignant NIT is favorable. Active treatment is strongly recommended.

Adenoma, Islet Cell↗
PubMed2002

Response to pain by different gestational age neonates.

One hundred infants were divided into the following 3 gestational age (GA) groups: (I) premature infants (n = 30) with the gestational age between 29 and 32 weeks; (II) premature infants (n = 30) with the gestational age between 33 and 36 weeks; (III) full-term infants (n = 40). The recorded responses of all infants to pain included the behavioral responses to painful stimuli (cry, facial activity and limbs movement) and the variety of heart rate. The results indicated that the infants of 3 groups had different degree response to various painful stimuli. Pain expression in full term infants was more significant than premature infants to same stimuli. 33-weeks GA infants were differential from 29-weeks GA infants. Full term infants showed more vertical mouth stretch and more taut tongue and more hand to mouth than premature infants, but more horizontal mouth stretch in premature infants.

Gestational Age↗
PubMed2002

Origin of two isoprenoid units in a lavandulyl moiety of sophoraflavanone G from Sophora flavescens cultured cells.

Cell suspension cultures of Sophora flavescens produced large amounts of sophoraflavanone G, an 8-lavandulylated flavanone and lupalbigenin, a 6,3'-di-dimethylallylated isoflavone, by the simultaneous addition of cork tissues and methyl jasmonate. The labeling pattern of the isoprene units resulting after administration of [1-13C] glucose into the cell cultures in the presence of the above additives revealed that two isoprene units in the lavandulyl group of sophoraflavanone G and two dimethylallyl groups of lupalbigenin were biosynthesized via the 1-deoxy-D-xylulose-5-phosphate pathway.

Butadienes↗
PubMed2002

Selective mitochondrial glutathione depletion by ethanol enhances acetaminophen toxicity in rat liver.

Chronic alcohol consumption may potentiate acetaminophen (APAP) hepatotoxicity through enhanced formation of N-acetyl-p-benzoquinone imine (NAPQI) via induction of cytochrome P450 2E1 (CYP2E1). However, CYP2E1 induction appears to be insufficient to explain the claimed magnitude of the interaction. We assessed the role of selective depletion of liver mitochondrial glutathione (GSH) by chronic ethanol. Rats were fed the Lieber-DeCarli diet for 10 days or 6 weeks. APAP toxicity in liver slices (% glutathione-S-transferase alpha released to the medium, GST release) and NAPQI toxicity in isolated liver mitochondria (succinate dehydrogenase inactivation, SDH) from these rats were compared with pair-fed controls. Ethanol induced CYP2E1 in both the 10-day and 6-week groups by approximately 2-fold. APAP toxicity in liver slices was higher in the 6-week ethanol group than the 10-day ethanol group. Partial inhibition of NAPQI formation by CYP2E1 inhibitor diethyldithiocarbamate to that of pair-fed controls abolished APAP toxicity in the 10-day ethanol group only. Ethanol selectively depleted liver mitochondrial GSH only in the 6-week group (by 52%) without altering cytosolic GSH. Significantly greater GSH loss and APAP covalent binding were observed in liver slice mitochondria of the 6-week ethanol group. Isolated mitochondria of the 6-week ethanol group were approximately 50% more susceptible to NAPQI (25-165 micromol/L) induced SDH inactivation. This increased susceptibility was reproduced in pair-fed control mitochondria pretreated with diethylmaleate. In conclusion, 10-day ethanol feeding enhances APAP toxicity through CYP2E1 induction, whereas 6-week ethanol feeding potentiates APAP hepatotoxicity by inducing CYP2E1 and selectively depleting mitochondrial GSH.

Acetaminophen↗
PubMed2002

Effects of ethanol dose and ethanol withdrawal on rat liver mitochondrial glutathione: implication of potentiated acetaminophen toxicity in alcoholics.

Chronic ethanol consumption potentiates acetaminophen (APAP) hepatotoxicity through enhanced NAPQI formation via CYP2E1 induction and selective depletion of mitochondrial glutathione. Because the prevalence of the interaction is extremely low given the use of APAP and the incidence of alcohol abuse, we studied the effects of ethanol dose and ethanol withdrawal on selective mitochondrial glutathione (GSH) depletion and APAP toxicity in liver slices. Rats were fed the Lieber-DeCarli diet containing ethanol (0, 7, 18, 27, and 36% total energy) for 6 weeks. The highest ethanol-containing diet (36% energy as ethanol) was replaced by control diet for 2, 5, 12, and 17 h. Maximal CYP2E1 induction was caused by 36% energy as ethanol diet (2.2-fold, p < 0.05 versus control). The activity and liver protein content returned to the control level 17 h after ethanol withdrawal. The 36% energy as ethanol diet caused maximal mitochondrial GSH depletion (51%, p < 0.05 versus control), which was restored 17 h after ethanol withdrawal (22.0 +/- 4.9 versus 11.7 +/- 1.7 nmol/mg protein of 0 h, p < 0.01). Elevated glutathione S-transferase-alpha release in liver slices (a measure of toxicity) was observed in rats fed 36% energy as ethanol diet (1 mM APAP: 69 +/- 10 versus 3 +/- 1% of control, p < 0.01). Enhanced toxicity disappeared when ethanol dose decreased and when ethanol was removed (7.2% ethanol: 3 +/- 1% and 17 h: 2 +/- 1%, p < 0.01 versus 0 h 36% energy as ethanol). In conclusion, high-dose ethanol potentiated APAP hepatotoxicity via CYP2E1 induction and selective mitochondrial GSH depletion. Mitochondrial GSH depletion quickly reversed when ethanol was withdrawn. The time window for both mechanisms to act in concert is narrow.

Acetaminophen↗
PubMed2002

Regulation of lithospermic acid B and shikonin production in Lithospermum erythrorhizon cell suspension cultures.

Cell suspension cultures of Lithospermum erythrorhizon produced a large amount of lithospermic acid B, a caffeic acid tetramer, as well as shikonin derivatives (each ca. 10% of dry wt.) when cultured in shikonin production medium M-9. Various culture factors for increasing the production of lithospermic acid B were investigated. Lithospermic acid B production was inhibited by 2, 4-D or NH4+, whereas it was stimulated by Cu2+. These regulatory patterns were similar to those for the production of shikonin derivatives in these cell cultures, suggestive of close relations and similar metabolic regulation between the production of these compounds. Cultivation under light illumination, however, showed that these metabolisms were independently regulated. In particular, blue light showed a stimulatory effect on lithospermic acid B production, while shikonin production was strongly inhibited, indicative of an effective condition for lithospermic acid B production.

Benzofurans↗
PubMed2002

Occurrence of Salmonella enterica serotype typhimurium DT104A in retail ground beef.

Surveillance data of cattle and human isolates of Salmonella enterica serovar Typhimurium DT104 indicate that this pathogen emerged worldwide in the 1980s, particularly in cattle. Studies were conducted to determine the prevalence of Salmonella Typhimurium DT104 in ground beef. Samples were also tested for the presence of generic Escherichia coli. A total of 404 fresh ground beef samples obtained at retail stores from New York, San Francisco, Philadelphia, Denver, Atlanta, Houston, and Chicago were shipped overnight to Georgia for processing. Salmonella spp. were isolated from 14 (3.5%) samples. Eight different serotypes were identified among the isolates, including Salmonella Typhimurium (5), Salmonella Lille (3), Salmonella Montevideo (1), Salmonella Hadar (1), Salmonella Meleagridis (1), Salmonella Cerro (1), Salmonella Kentucky (1), and Salmonella Muenster (1). Antibiotic resistance profiles indicated that all five Salmonella Typhimurium isolates were resistant to ampicillin, streptomycin, sulfamethoxazole, ticarcillin, and tetracycline but that they were sensitive to chloramphenicol. Phage typing revealed that all five Salmonella Typhimurium isolates were DT104A, a subtype of DT104. All five Salmonella Typhimurium DT104A isolates were obtained from ground beef sampled from retail outlets in San Francisco. Pulsed-field gel electrophoresis (PFGE) genomic DNA profiles of the five Salmonella Typhimurium DT104A isolates from ground beef were indistinguishable from those of four control Salmonella Typhimurium DT104 penta-resistant isolates from cattle that were used for comparison. A total of 102 generic E. coli isolates were obtained, only three of which were multiresistant to antibiotics. In addition, three E. coli isolates were recovered from samples that were positive for Salmonella Typhimurium DT104A. No correlation of antibiotic resistance profiles was observed between Salmonella Typhimurium DT104A and generic E. coli, as two of the three E. coli isolates were susceptible to all of the antibiotics tested, and the third isolate was resistant only to cephalothin. These data indicate that Salmonella Typhimurium DT104A can be isolated from retail ground beef, and because there was little overlap in antibiotic resistance patterns between Salmonella Typhimurium DT104A and E. coli isolates from the same ground beef samples, these limited data suggest that the transfer of antibiotic resistance genes among enteric bacteria in ground beef may not be common. This latter observation is further supported by the limited isolation of multiantibiotic-resistant E. coli from retail ground beef.

Animals↗
PubMed2002

Marine oil spill contingency planning.

According to the practice researching and formulating "The Oil Spill Contingency Plan of South Chinese Sea", this paper analyses and discusses the structure, functions and main contents of marine oil spill contingency planning, programs the organizing and commanding system and emergency response system, and advances the planning and researching method to coordinate comprehensively and to design practically the detailed emergency response steps until to formulate the ease operating programs for the plan implementation(PPI) and the PPI to apply high-techniques supporting emergency administrations and response.

Disaster Planning↗
PubMed2002

[A study of the pour blood and the oxygen metabolic in tissue for extra-artery fascia flap].

OBJECTIVE: The aim of the work was to study the change for blood pour into the artery fascial flap and oxygen metabolic in tissue that knew the process of the flap. METHODS: We do the artery fascial flap in the rabbit, then measured the skin capillary blood flow and the content of the MDA. RESULTS: The content of the MDA rise when the blood flow descends in the flap, but it lives well. CONCLUSIONS: That the content of the MDA rise as time the blood flow descend in the flap is a gradual process of the whole flap from tip to end, the flap will not appear necrosis until the MDA reach a rather degree.

Animals↗
PubMed2002

[Clinical and pathological analysis collision carcinoma: report of 7 patients].

OBJECTIVE: To study the epidemiological, pathological, clinical features and therapy of collision carcinoma. METHODS: Seven patients were studied retrospectively against the background of the literature from 1980 to 2001, including the incidence, age of onset, sex ratio, predilection sites, clinical signs, pathological features and therapies. RESULTS: Collision carcinoma is rare, but more common in males than in females. The peak onset age is more than 65 years. It is found frequently in the stomach, liver, uterine, esophagogastric junction, and lung. Without special clinical features, it is difficult to diagnose. Pathological findings are the only way to make a correct diagnosis before operation. Operation is the major therapy, assisted by chemotherapy or/and radiotherapy when necessary. Collision carcinoma represents a coexistence of two adjacent but histologically different malignant neoplasmas without histological admixture in an organ. CONCLUSIONS: Collision carcinoma is rare but composed of mosaics of two malignant tumours. The clinical features of collision carcinoma need further investigation.

Adolescent↗