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Biomedical subjects

Jun Zhu

Publications and source records attributed to Jun Zhu.

At least 55 records · Page 3Linked to original sources

A robust statistical procedure to discover expression biomarkers using microarray genomic expression data.

Microarray has become increasingly popular biotechnology in biological and medical researches, and has been widely applied in classification of treatment subtypes using expression patterns of biomarkers. We developed a statistical procedure to identify expression biomarkers for treatment subtype classification by constructing an F-statistic based on Henderson method III. Monte Carlo simulations were conducted to examine the robustness and efficiency of the proposed method. Simulation results showed that our method could provide satisfying power of identifying differentially expressed genes (DEGs) with false discovery rate (FDR) lower than the given type I error rate. In addition, we analyzed a leukemia dataset collected from 38 leukemia patients with 27 samples diagnosed as acute lymphoblastic leukemia (ALL) and 11 samples as acute myeloid leukemia (AML). We compared our results with those from the methods of significance analysis of microarray (SAM) and microarray analysis of variance (MAANOVA). Among these three methods, only expression biomarkers identified by our method can precisely identify the three human acute leukemia subtypes.

Biomarkers↗

Statistics for correlated data: phylogenies, space, and time.

Here we give an introduction to the growing number of statistical techniques for analyzing data that are not independent realizations of the same sampling process--in other words, correlated data. We focus on regression problems, in which the value of a given variable depends linearly on the value of another variable. To illustrate different types of processes leading to correlated data, we analyze four simulated examples representing diverse problems arising in ecological studies. The first example is a comparison among species to determine the relationship between home-range area and body size; because species are phylogenetically related, they do not represent independent samples. The second example addresses spatial variation in net primary production and how this might be affected by soil nitrogen; because nearby locations are likely to have similar net primary productivity for reasons other than soil nitrogen, spatial correlation is likely. In the third example, we consider a time-series model to ask whether the decrease in density of a butterfly species is the result of decreases in its host-plant density; because the population density of a species in one generation is likely to affect the density in the following generation, time-series data are often correlated. The fourth example combines both spatial and temporal correlation in an experiment in which prey densities are manipulated to determine the response of predators to their food supply. For each of these examples, we use a different statistical approach for analyzing models of correlated data. Our goal is to give an overview of conceptual issues surrounding correlated data, rather than a detailed tutorial in how to apply different statistical techniques. By dispelling some of the mystery behind correlated data, we hope to encourage ecologists to learn about statistics that could be useful in their own work. Although at first encounter these techniques might seem complicated, they have the power to simplify ecological research by making more types of data and experimental designs open to statistical evaluation.

Animals↗

[HLA-A, B, DRB1 gene polymorphism of Beijing population was studied by high-resolution polymerase chain reaction sequence-based typing].

OBJECTIVE: To investigate the gene polymorphism of human leukocyte antigen (HLA)-A, B, DRB1 loci in the population of Beijing region, and research on the application feasibility of polymerase chain reaction sequence-based typing (PCR-SBT) method. METHODS: PCR-SBT method was applied to determine HLA- A, B, DRB1 genotypes of 618 unrelated healthy individuals of Beijing region. RESULTS: A total of 84 different alleles and 199 genotypes of HLA-A, 143 alleles and 366 genotypes of HLA-B, 122 alleles and 286 genotypes of HLA-DRB1 were detected. CONCLUSION: The results showed the characteristics of HLA-A, B, DRB1 distributions, and provided more comprehensive and accurate gene data that may serve as normal reference values for all of Beijing people.

Asian People↗

[Genetic and correlation analysis for agronomic traits in flue-cured tobacco (Nicotiana tabacum L.)].

By using a genetic model including additive and dominance effects and their interaction with environments, 7 agronomic traits were analyzed for a diallel design in 4 environmental conditions with 14 flue-cured tobacco varieties (or breeding lines) and their 41 F1 crosses. It was revealed that additive effects were the major genetic component for plant height, internode length, and width of leaves. Number of leaves and length of leaves were mainly controlled by dominance x environment interaction effects. Additive x environment interaction effects and dominance x environment interaction effects played a major role for girth of stem. Yield performance was mainly controlled by additive effects and dominance x environment interaction effects. The varieties adapted to local environments tended to have highly positive additive effects. Dominance effects and the dominance x environment interaction effects could perform differently in positive or negative direction for many crosses. The breeding program for hybrids should consider the adaptation of hybrids to specific ecological environments. The analysis of correlation among agronomic traits indicated that most of phenotypic, genotypic, additive and dominance correlation coefficients were positive. Additive correlations were predominance in genetic correlations for most pairs of traits. Yield can be improved by indirect selection on plant height.

Genotype↗

[Effect of Guanfu Base A in patients with ventricular arrhythmias].

OBJECTIVE: To investigate the effect and safety of intravenous Guanfu Base A hydrochloride (GFA) in the treatment of ventricular arrhythmias. METHODS: Patients without severe structural heart disease presenting with equal or more than 150 premature ventricular contractions per hour and/or non sustained ventricular tachycardia in drug-free holter monitoring were recruited in this double blind randomized active-controlled study. Eligible patients were randomly assigned to receive GFA or propafenone intravenously by a proportion of 1:1 in a double-blind manner. Intravenous bolus of the study medicine was given, followed by maintenance infusion for 6 hours. 24 hours continuous electrocardiographic recordings were performed to evaluate the efficacy. Vital signs, electrocardiograms and adverse events were documented before, during and after drug administration. RESULTS: A total of 201 patients came from eight centres were randomized to GFA or propafenone group. The demographic characteristics, the extent of ventricular arrhythmias and baseline clinical findings were comparable between the two groups. There were no significant differences in the percentage of reducing premature ventricular contractions and the accumulated efficacy between two groups. GFA had tendency to be more effective than propafenone in reducing the number of ventricular ectopy (P = 0.0609). There were no significant differences in the onset of action after drug administration between two drugs. The tolerance of GFA was better than propafenone. The adverse events in GFA group were less severe than those in propafenone group. CONCLUSIONS: Intravenous GFA in controlling the premature ventricular contraction has comparable effect to IV propafenone. Tolerance of GFA was better than propafenone.

Adolescent↗

[Application of multiparameter flow cytometry in diagnosis of non-Hodgkin lymphoma].

OBJECTIVE: To evaluate the role and application of flow cytometry in the diagnosis of non-Hodgkin lymphoma (NHL). METHODS: Fresh cell samples from 40 cases of lymphoproliferative disorders were obtained by fine needle aspiration or excisional biopsies. Multiparameter flow cytometry was used to study the surface antigens of lymphoid cells. The immunophenotyping results were also correlated with morphologic features seen in the cytology preparations. RESULTS: Of the 40 cases with histologic diagnosis of NHL, 37 cases (92.5%) had the lymphoma diagnosis confirmed by this method. The concordance rate for the 20 cases of B-cell NHL was 100%. As for the 17 cases with histologic diagnosis of T-cell NHL, 12 cases (66.7%) were correctly diagnosed as T-cell NHL using flow cytometry, while 2 cases (11.8%) were interpreted as B-cell NHL and the remaining 3 cases (17.6%) were undiagnosed. CONCLUSION: Immunophenotyping by flow cytometry can serve as an ancillary technique in diagnosis and subclassification of NHL.

Adolescent↗

[Passive FTIR remote sensing of gaseous pollutant in heated plume].

The principle and techniques of passive remote sensing of gaseous pollutant in heated plume was illustrated and discussed in this paper. The algorithm of radiance spectra and transmittance spectra in measured region was proposed, and the method of retrieving gas concentrations with NLLS fitting algorithm was also proposed. The remote senseing of actual gaseous pollutant of smokestack was done, and the quantitative analysis of SO2 and CO2 was completed.

English Abstract↗

[Error analysis and calibration method of complex spectrum of Fourier transform infrared spectrometer].

The phase shift in complex spectrum of Fourier transform infrared (FTIR) spectrometer was discussed. A rigorous derivation showed the relation between the phase shift and complex spectrum. The reason for the radiation offset in FTIR measurement was analysed. The present article presents a calibration method of FTIR complex spectrum, which can adjust the radiation offset. The comparison between experiment data and theoretical computation showed that the method is precise.

English Abstract↗

[Prevalence analysis on congenital hydrocephalus in Chinese perinatal from 1996 to 2004].

OBJECTIVE: To study the epidemiological characteristics of congenital hydrocephalus in Chinese perinatal. METHODS: From 1996 to 2004, data gained from Chinese Birth Defects Monitoring Network were used to depict the epidemiology of congenital hydrocephalus in China. All perinatal born in hospitals had an access within 7 days after delivery. The affected cases were divided into two groups-isolated and syndromic hydrocephalus. And prevalence rates were calculated by year, by sex, by birth area (urban versus rural), by maternal age group and by geographic area (north versus south). Of the affected, fetal age at birth, birth weight, perinatal outcome and prenatal diagnosis were analysed. RESULTS: All 3012 perinatal with congenital hydrocephalus were identified among 4,282,536 births, then an overall prevalence rate was 7.03/10,000, rates of isolated and syndromic hydrocephalus were 5.67/10,000 and 1.36/10,000 respectively. Furthermore, the annual prevalence rates of hydrocephalus presented an increasing trend during that period. The rates in male and female births, in urban and rural area, were 7.09/10,000 and 6.76/10,000, 5.49/10,000 and 10.10/10,000 respectively. There were significant differences among maternal-age-specific prevalence rates, the highest (11.42/10,000) was in an age < 20 years group. For total and isolated hydrocephalus, higher rates were found in north part of China. On the contrary, a higher rate of syndromic hydrocephalus was observed in south part of China. Among the infants with hydrocephalus, the ratio of preterm delivery and of low birth weight were 57.97% and 50.92% respectively. The ratio of congenital hydrocephalus diagnosed antenatally, which could be an indicator representing the capability of detecting the malformation both prenatally and postnatally, showed an upward trend similar to the prevalence rates. The perinatal fatality rates of the total, isolated and syndromic hydrocephalus were 87.75%, 88.66% and 83.91% correspondingly. CONCLUSION: Based on comparison between prevalence rates in China and those reported in foreign countries, our country might be listed into a higher epidemic region of the congenital hydrocephalus. Significant differences were identified between rural and urban areas, between north and south parts of China. The improvement ability in prenatal and postnatal diagnosis should be partly accounted for the increasing prevalence rates of hydrocephalus in Chinese perinatal. The poor birth quality of the affected predicts poor prognosis.

China↗

[Surface enhanced Raman scattering spectra of phytic acid in the sol silver oxide].

Surface enhanced Raman scattering spectra of phytic acid were recorded in the sol oxide silver. Based on ab-initio/ STO-3 quantum calculations results, assignments to the vibrational modes of phytic acid were carried out. On the basis of the mechanism of SERS, the adsorption modes were suggested that phytic acid chemically adsorbed on the oxide silver surface through four phosphate bonds.

English Abstract↗

[The study of infrared background radiation of earth and atmosphere by airborne FTIR spectrometer].

The present article describes the experiment of airborne Fourier transform infrared (FTIR) spectrometer detecting the background radiation of earth and atmosphere. Considering the surface radiation and atmospheric absorbance and emission, the expression of radiations measured by airborne FTIR is given. It is indicated that the background radiations depend on four parameters: surface temperature, surface emissivity, atmospheric transmission and temperature. Based on theoretic analysis the measured spectra are compared and analyzed according to the differences in altitude and surface. Spectral characters of infrared background radiation are described.

English Abstract↗

[Effects of Apatococcus lobatus parasitization on leaf photosynthesis characteristics of orange (Citrus cv. Olinda)].

With 2-year pot-grown grafted Citrus cv. Olinda as test material, this paper studied the effects of Apatococcus lobatus parasitization on its leaf photosynthesis characteristics. No significant differences were observed between slightly affected and control leaves in their total chlorophyll (Chl a + b) and carotenoid (Car) contents, net photosynthetic rate (P(n)), intercellular CO2 concentration (C(i)), primary maximum photochemical efficiency of PS II (F(v)/F(m)), quantum efficiency of noncyclic electron transport of PS II (phiPS II), and photochemical quenching (qP), but for medium and severely affected leaves, their Chl a + b, Car, P(n), F(v)/F(m), phiPS II and qP decreased by 23.85%, 26.49%, 43.3%, 4.5%, 35.1% and 22.5%, and 37.61%, 44.04%, 64.5%, 8.6%, 63.6% and 40.1%, respectively, while C(i) increased, with significant differences to the control. It could be concluded that the massive parasitization of A. lobatus caused a stress to orange plant, and non-stomatal limitation was the dominating factor of P(n) reduction.

Chlorophyll↗

[Reversed phase high-performance liquid chromatography for determination of plasma olanzapine and pharmacokinetics of olanzapine in healthy Chinese volunteers].

OBJECTIVE: To establish a reversed phase high-performance liquid chromatography (HPLC) system for determining plasma concentration of olanzapine and analyze the pharmacokinetics of olanzapine in healthy Chinese volunteers. METHODS: Ten healthy male subjects received a single oral dose of 20 mg olanzapine tablets. The plasma concentrations of olanzapine were determined by HPLC, and the data were analyzed using 3P97 program. RESULTS: The plasma concentration curve of olanzapine following a single oral dose conformed to the two compartment open model. The main pharmacokinetics parameters of olanzapine were as follow: C(max) was 113.7-/+33.1 microg/L, T(max) 5.07-/+0.65 h, t(1/2) 35.44-/+4.21 h, AUC(0-144) 2,235-/+257 microg.h.L(-1), and AUC(0-inf) 2,516-/+301 microg.h.L(-1). CONCLUSION: The system established in this study allows for highly sensitive, selective and accurate determination of plasma concentration of olanzapine, and provides valuable information for clinical trials.

Adult↗

[Application of MALT-CLS method to FTIR quantitative analysis of atmospheric trace gas].

The MALT-CLS method for quantitative analysis of atmosphere trace gas by FTIR spectrometry was studied. Some experiments are described, such as long-path White cell, and passive remote sensing of aircraft. The characteristic of this method is that the calibration spectra are calculated from a database of absorption line parameters HITRAN using MALT program, including environmental and instrumental effects in the calculation. It is particularly useful in long open-path and solar FTIR spectroscopy, or passive remote sensing by FTIR.

English Abstract↗

[The Chinese registry on reperfusion strategies and outcomes in ST-elevation myocardial infarction].

OBJECTIVE: To analyze the current use of reperfusion strategies and the outcomes of patients with ST elevation acute coronary syndromes (ACS) in China. METHODS: A total of 518 consecutive patients (371 male and 147 females, mean age 65 +/- 11) with ST elevation ACS or newly discovered left bundle branch block were registered from 20 hospitals from 5 regions (ranging from large regional centre hospitals to small county hospitals) in China. Patient general characteristics, reperfusion patterns and outcomes were analyzed. Patients were followed up for 3 months. RESULTS: The median time from pain onset to presentation at the hospital was 4 hours. Pre-hospital delay > 12 hours was found in 20% patients. Fifty-six percent patients (292/518) underwent reperfusion therapy (134 with primary percutaneous coronary intervention and 158 with fibrinolysis). The median time from admission to reperfusion (door-to-needle) was 65 min in fibrinolysis group and 110 min (door-to-cath) in primary PCI group respectively. Urokinase was used in 67% (106/158) patients underwent fibrinolysis. Multivariate logistic regression analysis showed that age >/= 75 years (P < 0.01), previous myocardial infarction (P < 0.01) and history of congestive heart failure (P < 0.05) were associated with no reperfusion therapy. Mortality and congestive heart failure rates were significantly higher in patients with no reperfusion therapy not only at discharge (P < 0.01) but also at 3 months (P < 0.01) compared to patients underwent reperfusion. The incidence of combined outcomes (death or MI, and death, MI or Strobe) was also higher in patients without reperfusion therapy at 3 months (all P < 0.01) compared to patients underwent reperfusion. There were no differences on combined outcomes between fibrinolysis and primary PCI subgroups. CONCLUSION: Reperfusion therapy was the primary treatment of choice to improve the outcomes of patients with ST elevation ACS. Strategies to increase reperfusion therapy rate for ST elevation ACS are urgently needed in China.

Aged↗

[Functional analysis of rice P0491E01 gene regulating anther development].

The rice P0491E01 gene shares high similarity in amino acid sequence with Arabidopsis gene AtDAD1 (DEFECTIVE IN ANTHER DEHISCENCE1) which plays a key role in the biosynthesis of jasmonic acid. In this paper, we investigated the function of this gene in the anther development of rice using RNA interference strategy. An exon fragment of 263bp was cloned from genomic DNA of P0491E01 to construct RNAi vector pP0491RNAi. Then, pP0491RNAi was transformed into O. sativa japonica by Agrobacterium-mediated transformation and ten transgenic plants were obtained. GUS-staining and PCR analysis confirmed that T-DNA was integrated into rice genome. Three of the transgenic plants were male sterile, and the other transgenic plants showed reduced fertility. Cytological observation indicated that anther development in the early stage of male sterile transgenic plants was normal, however, the microspores could not develop into mature pollen grains. Further investigations of the expression of P0491E01 gene in these transgenic lines by RT-PCR revealed that its transcription was significantly reduced. The results suggest that P0491E01 may play an important role during the late stage of anther development.

Cyclopentanes↗

[Study on serum erythropoietin levels in patients with hematologic malignancies].

OBJECTIVE: To study whether hematologic malignancy patients with anemia have a lower erythropoietin (EPO) response. METHODS: Serum EPO levels were detected by ELISA in patients with hematologic malignancies and with iron deficiency anemia (IDA). Eighty patients with hematologic malignancies, including 13 multiple myeloma (MM), 7 chronic lymphocytic leukemia (CLL) and 60 non-Hodgkin's lymphoma (NHL) were studied. Thirty of them had anemia(21 NHL,6 MM and 3 CLL). Twenty patients with IDA were studied as the control. RESULTS: Hematologic malignancy patients with anemia had higher EPO levels [(97.8 +/- 183.9) IU/L] than those with normal Hb values [(27.8 +/- 85.4) IU/L; P <0.01]. In patients with IDA, serum EPO response was inversely correlated with Hb level (r= -0.5, P <0.05) , but no such inverse correlation was found in the hematologic malignancy patients with anemia (r = -0.14). After corrected for Hb level, the serum EPO levels were significantly lower in anemic patients with hematologic malignancies than in IDA patients (P = 0.032) , indicating a decreased EPO response in the former group. CONCLUSION: Anemia associated with hematologic malignancy might result from an inappropriately low EPO response. EPO treatment for these patients may be beneficial.

Adolescent↗

A bench-scale aeration study using batch reactors on swine manure stabilization to control odour in post treatment storage.

A bench-scale study on swine manure stabilization for odour control was conducted using batch aeration reactors. In trial 1, two aeration lengths, i.e., 0.5 and 4.0 day, were used under uncontrolled ambient temperature that increased gradually over the experimental period. While in trial 2, a 16.0-day aeration scheme was employed under constant 17 degrees C. An airflow rate of 1.2L/s/m(3) was used for both trials to aerate batch reactors containing finishing pig manure with initial total solids (TS) levels ranging from 0.5 to 4.0%. Manure stabilization during the 90-day post-treatment storage was evaluated by the changes in organic materials, nitrogen and volatile fatty acids (VFA). The odour generation potential in the treated manure was determined by the changes in VFA. Up to 827 mL of liquid was lost due to aeration related foaming. The reductions in total volatile solids (TVS), 5-day biochemical oxygen demand (BOD(5)), total Kjeldahl nitrogen (TKN) and VFA during storage were improved when aeration length increased. Low solids levels offered a more advantageous circumstance for manure stabilization and odour control. Biodegradation of organic matter, removal of nitrogen, and breakdown of VFA would increase with increasing ambient temperature. VFA removals in manure under 16.0-day aeration were higher than those under 0.5- and 4.0-day aeration; however, VFA regeneration started to exceed its consumption on day 20 (4 days after the aeration treatment). BOD(5) was the best estimate of VFA concentration in the aerated manure during storage. The 4.0-day aeration scheme was sufficient to stabilize manure to effectively assuage odour generation potential during the 90-day storage under increasing ambient temperature conditions.

Animals↗