Clonal deletion is one mechanism responsible for tolerance in mixed hematopoietic chimeras.
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Animals↗
Biomedical subjects
Z Lin
Publications and source records attributed to Z Lin.
Vascular endothelial growth factor and other biological predictors related to the postoperative survival rate on non-small cell lung cancer.
OBJECTIVE: An analysis of postoperative 1-5 year-survival rates related to vascular endothelial growth factor (VEGF) and vascular endothelial growth factor receptor (VEGF-r), microvascular density (MVD), P53, H-ras, CerbB2, proliferative index (PI), divisional index (DI) were carried out on 127 cases of non-small cell lung cancer (NSCLC) treated with curative resection and aim to find out more sensitive molecular prognostic predictors for the reference of medicine and molecular pathology. METHODS: All the cases were staged strictly using the UICC criteria of 1997 and regional lymphonodes seen by the naked eye should be dissected and sent to pathology with lung specimens. Immunohistochemical analyses were used for those biological predictors. Kaplan-Meier curve, Cox univariance and multivariance analysis were used for the survival and prognostic predictors. RESULTS: 52 cases (40.9%) with high expression of VEGF showed a worse postoperative year-survival rate than cases with low expression, but no statistical difference. The difference of survival on stage I case with high and low expression were closed to be significant value (P=0.0643). P53, PI and DI were related to postoperative survival, P=0.0341, 0.0005 and 0.0162, respectively. Co-expression of VEGF combined with P53, PI and DI was calculated for the difference of year-survival rate by Cox multivariance analysis. The survival rates of cases with both negative VEGF +P53 or VEGF+PI co-expression rate were better than those with both positive or either positive, P values were 0.0159 and 0.0154, respectively. CONCLUSION: The post-operative year-survival of NSCLC was of no statistical difference between with high expression and low expression of VEGF, but in stage I case it was closed to be significant difference, it speculated that the neoangiogenesis is more obviously in early stage NSCLC, but in the later stage of NSCLC, it may be covered by more complicated molecular-biological factors such as P53 and other oncogens. Co-expression of VEGF combined with p53 or PI was more meaningful than a single biological predicator on survival rate of NSCLC, it is worth to do further studies.
Biomarkers, Tumor↗
Development of the NIST bone ash standard reference material for environmental radioactivity measurement.
The bone ash standard reference material (SRM), a blend of 4% contaminated human bone and 96% diluent bovine bone, has been developed for radiochemical method validation and quality control for radio-bone analysis. The massic activities of 90Sr, 226Ra, 230Th, 232Th, 234U, 235U, 238U, 238Pu, (239 + 240)Pu and (243 + 244)Cm were certified using a variety of radiochemical procedures and detection methods. Measurements confirmed undetectable radionuclide heterogeneity down to a sample size of 5 g. thereby implying adequate blending of particulate materials with dilution factors of up to 17,900. The results among most of the intercomparison laboratories and their methods were consistent. Disequilibrium was observed for decay chains: 234U(0.67 mBq/g)-230Th(0.47 mBq/g)-226Ra(15.1 mBq/g)-210Pb(23 mBq/g)-210Po(13 mBq/g) and 232Th(0.99 mBq/g)-228 Ra(6.1 mBq/g)-228Th(7.1 mBq/g). The disequilibria were the results of mixing occupationally contaminated human bone with natural bovine bone and the fractionation during internal biological processes. The massic activity of 210Pb, 228Th and 241Am were not certified because of insufficient 228Ra and 241Pu data and lack of knowledge in how 222Rn and its daughters will be fractionated in the SRM bottle over time.
Animals↗
An in vivo rat model for assessment of extrahepatic metabolism.
INTRODUCTION: Xenobiotic metabolism in extrahepatic tissues has been extensively studied in vitro, but it is difficult to estimate in vivo the share of xenobiotic transformation in extrahepatic tissues for lack of a suitable approach. In this paper an in vivo rat model for assessment of extrahepatic metabolism is described, and the model was investigated using the conversion of lidocaine to monoethylglycinexylidide (MEGX). METHODS: The rats were anesthetized with ethyl ether inhalation. The liver was exposed, the liver artery ligated, and the portal vein was clamped at its distal end. The left hepatic lobe was partly excised along its inferior margin, and a heparinized silicone catheter, diameter 0.2 cm, was inserted into the portal and left hepatic veins to allow the recirculation of portal vein blood. A sham operation was performed in the control group. RESULTS: Phenol red test showed that hepatic blood supply was absolutely blocked in model rats. At 30 min after establishing the portal-cavum bypass, the renal function and electrolytes did not change, but serum glucose decreased by 64.4 +/- 30.4%; 30 min after intravenous administration of 1.0% lidocaine 2 mg x kg(-1), serum MEGX in model rats was 32.0 +/- 7.14% of that in the control group, which mostly existed in a free form and was not induced by phenobarbital pretreatment. DISCUSSION: The model is easy to establish and provides an in vivo method to study the extrahepatic metabolism of xenobiotics.
Animals↗
Functional expression of horseradish peroxidase in E. coli by directed evolution.
In an effort to develop a bacterial expression system for horseradish peroxidase (HRP), we inserted the gene encoding HRP into the pET-22b(+) vector (Novagen) as a fusion to the signal peptide PelB. A similar construct for cytochrome c peroxidase (CcP) leads to high CcP activity in the supernatant. Expression of the wild-type HRP gene in the presence of isopropyl-beta-D-thiogalactopyranoside (IPTG) yielded no detectable activity against ABTS (azinobis(ethylbenzthiazoline sulfonate)). However, weak peroxidase activity was detected in the supernatant in the absence of IPTG. The HRP gene was subjected to directed evolution: random mutagenesis and gene recombination followed by screening in a 96-well microplate format. From 12 000 clones screened in the first generation, one was found that showed 14-fold higher HRP activity than wild-type, amounting to approximately 110 microg of HRP/L, which is similar to that reported from laborious in vitro refolding. No further improvement was obtained in subsequent generations of directed evolution. This level of expression has nonetheless enabled us to carry out further directed evolution to render the enzyme more thermostable and more resistant toward inactivation by H2O2. These results show that directed evolution can identify mutations that assist proteins to fold more efficiently in Escherichia coli. This approach will greatly facilitate efforts to "fine-tune" those many enzymes that are promising industrial biocatalysts, but for which suitable bacterial or yeast expression systems are currently lacking.
Biotechnology↗
Disordered eating in Japanese and Chinese female runners, rhythmic gymnasts and gymnasts.
Eating Attitude Test-26 (EAT-26) and self-administered questionnaires were used to survey eating attitudes and menstrual irregularity of Japanese (J) and Chinese (C) collegiate female runners (RUNs), rhythmic gymnasts (RGYMs), gymnasts (GYMs), and nonathletic controls (NAs). Athletes were recruited from several outstanding colleges for physical education and sport in each country. The prevalence of disordered eating (DE) was significantly higher in Japanese athletes (21% in JRUNs, 19% in JRGYMs, and 15% in JGYMs) than Chinese athletes (4% in CRUNs, 2% in CRGYMs, and none in CGYMs). Also, the prevalence of amenorrhea was very low in CRUNs (1%), CRGYMs (0%), and CGYMs (0%), as compared with their respective Japanese counterparts (JRUNs 22%, JRGYMs 10%, JGYMs 8%). There was no significant difference in the prevalence of DE and amenorrhea between Japanese and Chinese NAs. Multivariate logistic regression analysis using 10 independent variables regarding anthropometrics, athletics, weight and diet concern, and nationality indicated that high frequency of dieting during a lifetime, high athletic level and being Japanese were significant risks for the development of DE in athletes. It is concluded that the low prevalence of DE in the Chinese in this study is partly explained by the lack of socioculturally- and socioeconomically-imposed desire to be thin as well as by the low frequency of dieting during their lifetime.
Amenorrhea↗
Evaluation of analytical procedures for urinary codeine and morphine measurements.
Different analytical procedures for quantitation of total morphine and codeine in urine were evaluated. Hydrolysis of urine with hydrochloric acid and four different enzymes was compared. In order to effect complete hydrolysis of glucuronide conjugates, hydrolysis with 6.5M HCl containing bisulphite and heating at 100 degrees C for 20 min was required. Results using this hydrolysis procedure agreed well with results from direct analysis of free and conjugated forms by liquid chromatography. Use of more dilute HCl but at a higher temperature was not sufficient. Some enzymatic procedures appeared to give effective hydrolysis with a higher variability, but these procedures were more time-consuming. There was a good quantitative agreement between FID gas chromatography and ion-trap gas chromatography/mass spectrometry. The validated analytical procedure was applied to authentic patient samples.
Chromatography, Gas↗
Determination of the volatile anesthetics halothane, enflurane, isoflurane, and sevoflurane in biological specimens by pulse-heating GC-MS.
Four kinds of volatile anesthetics (halothane, enflurane, isoflurane, and sevoflurane) that were dissolved in 3 microL of experimental plasma samples were examined by the pulse-heating gas chromatographic-mass spectrometric method, and this approach was found to be reliable for qualitative and quantitative analysis. The analytical results also showed good recovery and accuracy. This method was then applied to real blood specimens taken from patients during surgery. The same blood specimens were also analyzed simultaneously by the conventional headspace method for comparison. The data for the clinical blood specimens examined by these two methods showed reasonable correlation coefficients of 0.914 (enflurane) and 0.937 (sevoflurane). These results indicate that the pulse-heating method is applicable for toxicological and clinical analysis of several kinds of volatile anesthetics.
Adult↗
Urine and plasma pharmacokinetics of codeine in healthy volunteers: implications for drugs-of-abuse testing.
Thirteen healthy volunteers participating in an open and randomized study received two single doses (25 and 50 mg) of codeine orally two weeks apart. Urine concentrations of opiates were studied for 96 h, and plasma concentrations of codeine and the metabolites codeine-6-glucuronide (C6G), morphine, morphine-3-glucuronide (M3G), and morphine-6-glucuronide (M6G) were monitored for 24 h. Plasma was analyzed by high-performance liquid chromatography. Measurements of urine were made with the EMIT opiate-screening assay and with gas chromatography-mass spectrometry for total (conjugates liberated by acid hydrolysis) codeine, morphine, and norcodeine. In urine, the ratio between total recovered morphine and codeine as expressed in percent ranged from 2.3 to 23.3% with a mean value of 9.8%. This ratio increased with time, and, in all but three subjects, rose to greater than 1 after 22-36 h. In 58% of cases, this occurred within the detection time in the EMIT assay. The detection time in the EMIT screening assay was found to be 20-39 h after the 25-mg dose and 30-52 h after the 50-mg dose. Elimination rates calculated from urine data corrected for creatinine concentration showed that morphine was eliminated more slowly than codeine. In plasma, the highest concentrations and area-under-curve values were observed for C6G, followed by codeine and M3G. All compounds had peak plasma values 1-2 h after dosing. The elimination of M3G was slower than that of C6G. We concluded that the relative proportion of codeine and morphine varies both between individuals and as a function of time and that morphine may be present in concentrations above those of codeine even after moderate and single doses of codeine. This must be taken into consideration when interpreting the presence of opiates during drugs-of-abuse testing.
Administration, Oral↗
The online screening technique for urinary benzodiazepines: comparison with EMIT, FPIA, and GC-MS.
Three commercial immunoassay systems (EMIT, EPIA, Online) for the screening of benzodiazepines in urine were evaluated using authentic patient samples with gas chromatography-mass spectrometry (GC-MS) as the reference method. The Online system (kinetic interaction of microparticles in solution) gained in performance by applying a 100-ng/mL cutoff limit and by incorporating beta-glucuronidase treatment, which could be automated on the Cobas Mira Plus instrument. When using enzymatic hydrolysis, all three immunoassay systems had high levels of sensitivity, including samples containing only flunitrazepam and nitrazepam metabolites. A high degree of concordance was observed between the Online and FPIA (fluorescence polarization immunoassay) systems when analyzing 138 randomly selected patient samples. The EMIT II and EMIT d.a.u. (enzyme multiplied immuno technique) systems gave a higher number of positive results, but the presence of benzodiazepines could not be verified by GC-MS in a substantial number of these cases. The rate of unconfirmed positive results was increased when enzyme hydrolysis was incorporated in the EMIT II assay. Although differences in the performances of the investigated assay systems were observed, they all seem appropriate for clinical use in detecting benzodiazepine intake in drug abusers when enzymatic hydrolysis is included.
Benzodiazepines↗
Reverse transcription-polymerase chain reaction and western blotting analysis for detection of p63 isoforms in uterine cervical cancers.
The aim of this study was to investigate the role of TAp63 and DeltaNp63 isoforms in uterine cervical cancers. The messenger RNA (mRNA) and protein expressions of TA and DeltaN forms as well as alpha, beta, and gamma isoforms of p63 were studied in seven SiHa, ME-180, SNU17, SNU902, SNU1160, SNU703, and SNU1299 human papillomavirus (HPV)-positive uterine cervical squamous cell carcinoma (SCC) cell lines, one HT3 HPV-negative SCC cell line, and one HeLa adenocarcinoma cell line using reverse transcription-polymerase chain reaction (RT-PCR) and western blotting. Fresh nonneoplastic and neoplastic tissues of uterine cervical and endometrial cancers were also studied. RT-PCR for TA and DeltaN form and three isoforms of p63 showed positive bands for both TA and DeltaN forms and for all three isoforms in cervical cancer cell lines but weak band for alpha isoform in HPV-negative HT3 SCC cell line and no band for beta isoform in HeLa adenocarcinoma cell line. RT-PCR for TA and DeltaN and three isoforms of p63 mRNA in tissue samples showed positive bands in almost all samples, except for gamma isoform, the expression was weak or absent in nonneoplastic tissues compared with neoplastic tissues. In western blotting, cancer cell lines and both nonneoplastic and neoplastic tissue samples showed expression of TA and DeltaN, and gamma isoform but beta isoform expression with or without alpha isoform was only found in cancer cell lines and neoplastic tissues. beta isoform, possibly of DeltaNp63, may be considered as an important isoform in uterine cervical squamous cell carcinogenesis.
Biomarkers, Tumor↗
The impact of California's smoking ordinances on worksite smoking policy and exposure to environmental tobacco smoke.
A subsample of 5776 respondents to the California Tobacco Survey who do not smoke and work indoors outside of their home was analyzed regarding worksite smoking policy and worksite exposure to environmental tobacco smoke. To obtain study results, survey responses were linked to tobacco ordinance data. Nonsmokers who worked in localities with moderate or strong laws were more likely to report worksite smoking policies than nonsmokers in localities without laws. Even in localities with strong laws, 23.5% of respondents reported no worksite policy, and 26.4% reported recent exposure to environmental tobacco smoke at the worksite. Comprehensive laws with minimal exemptions may be necessary to ensure adequate compliance and protection from environmental tobacco smoke.
Adolescent↗
As2O3 induces apoptosis of the human B lymphoma cell line MBC-1.
OBJECTIVE: To see how arsenic trioxide (As2O3) affects proliferation of the human B lymphoma cell line MBC-1. METHODS: We studied the effect of As2O3 on MBC-1 cells and its mechanism by morphological observation, flow cytometry assay and DNA gel electrophoresis. RESULTS: As2O3 could upregulate p53 gene expression at protein level, inducing cell apoptosis and inhibiting the proliferation of MBC-1 cells. Upregulation of p53 expression appears to be important in the apoptosis of MBC-1 cells. CONCLUSIONS: As2O3 can inhibit the proliferation of MBC-1 cells by upregulating p53 gene expression, thus inducing apoptosis.
Antineoplastic Agents↗
Beyond rheology modifications: hydrophilically modified silicone elastomers provide new benefits.
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Cosmetics↗
Both human SP-A1 and Sp-A2 genes are expressed in small and large intestine.
The human SP-A locus consists of two functional genes and one pseudogene, and SP-A is shown to play a role in local host defense and the regulation of inflammation in lung. Because the intestine, like the lung, is constantly exposed to foreign and potentially harmful substances, we investigated the hypothesis that both human SP-A genes are expressed in intestine. We demonstrate that both SP-A genes are expressed in human small and large intestine. The presence of SP-A mRNA in human intestine was detected by reverse transcription polymerase chain reaction (RT-PCR), Northern blot analysis, and immunohistochemistry. The size of intestinal SP-A mRNA is the same as that in human lung, but the level of expression, compared with that in the lung, is very low in both the small and large intestine. Immunohistochemical analysis revealed positive reactivity for SP-A in a subgroup of epithelial cells in the intestine. Expression of both SP-A1 and SP-A2 genes was established by gene-specific PCR amplification, PCR-based converted RFLP discrimination, and direct sequencing of RT-PCR products. We speculate that SP-A in the intestine plays a role in local host defense and inflammation.
Blotting, Northern↗
Pulmonary alveolar proteinosis: a review.
Pulmonary alveolar proteinosis (PAP) is a disorder that rapidly leads to respiratory failure, because the alveolar spaces fill with a lipid-rich, proteinaceous material that impedes gas exchange. The pathogenesis of this life-threatening process remained an enigma for decades. Recent analysis of the lung pathology and molecular genetics of affected families has provided a molecular basis for some cases of PAP-deficiency of surfactant protein SP-B. This lack result from mutations in the gene for SP-B. The common mutation, 121ins2, is present in about two-third of the patients with SP-B deficiency. Additional insights into the mechanism for this lipoproteinaceous accumulation within alveoli were contributed by serendipity in a granulocyte-macrophage colony stimulating factor (GM-CSF) knock-out mouse model developed to study basal hematopoiesis. In this model, hematopoiesis was unaffected, but the animals developed pulmonary alveolar proteinosis. Subsequently, mutations in the genes for GM-CSF or its receptor were identified as the cause for pulmonary alveolar proteinosis in some patients. In our review, we discuss the known clinical, pathologic, and molecular genetic aspects of pediatric PAP and consider avenues for future research.
Animals↗
A novel kind of antitumour drugs using sulfonamide as parent compound.
To obtain potent antitumour agents with low toxicity, sulfonamide derivatives containing 5-flurouracil and nitrogen mustard, respectively are designed and synthesised. 1-(3-(4-Acetylaminobenzenesulfonamido)-3-oxopropyl)-5-fluoropyrimidine-2,4-dione (4) was obtained by the coupling of p-acetamidobenzenesulfonamide with 3-(5-fluorouracil-1-yl) propionic acid. The hydrolysis of 4 led to 1-(3-(4-aminobenzenesulfonamido)-3-oxopropyl)-5-fluoropyrimidine-2,4-dione (5). Treatment of p-acetamidobenzenesulfonyl chloride with bis(2-chloroethyl) amine led to 4-acetylamino-N,N-bis(2-chloroethyl)benzenesulfonamide (6). Subsequent hydrolysis of 6 in hydrochloric acid led to 4-amino-N,N-bis(2-chloroethyl)benzenesulfonamide hydrochloride (7). Two different synthetic route were investigated in the synthesis of 2-[N(1)-2-pyrimidyl-aminobenzenesulfonamido] ethyl 4-bis(2-chloroethyl) aminophenyl butyrate (12b). Carbobenzyloxy was proved to be unsuitable for the protection of the aromatic amino group of sulfadiazine since the pyrimidine ring was also hydrogenated at the last step of the first route under the deprotection condition. In another route, acetyl was firstly used as the protective group, then it was replaced by the Schiff's base. The reaction of chlorambucil with 2-[N(1)-2-pyrimidinyl-(p-acetyl)aminobenzenesulfonamido] ethanol (10b) afforded 2-[N(1)-2-pyrimidinyl-(p-benzylidene)aminobenzenesulfonamido] ethyl 4-bis(2-chloroethyl) aminophenyl butyrate (11b). Compound 12b was obtained by the hydrolysis of 11b. The acute toxicity and antitumour activity of 5, 7 and 12b have been investigated in mice. Compound 12b exhibited high antitumour activity and low toxicity with a therapeutic index (TI) of 47.55.
Animals↗
Direct correlation between the titer of infectious bursal disease virus VP2-specific antibody and protection.
The titer of antibody specific to infectious bursal disease virus (IBDV) was measured by a new method and correlated with protection. Challenge was carried out in chickens with various antibody titers, which were measured using a latex agglutination-inhibition (LI) test, a rapid and easy technique for measuring IBDV VP2-specific antibody. When actively immunized chickens had LI titers of 1:2 or more, almost all were protected from subsequent challenge with highly virulent IBDV. In contrast, even when chickens passively immunized with maternally derived antibody had LI titers of 1:4, half were susceptible to the same challenge.
Agglutination Tests↗