REL-positive double minute chromosomes in follicular lymphoma.
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Adult↗
Biomedical subjects
Y Ning
Publications and source records attributed to Y Ning.
Detection of MOZ-CBP fusion in acute myeloid leukemia with 8;16 translocation.
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Acute Disease↗
Maternal recreational physical activity is associated with plasma leptin concentrations in early pregnancy.
BACKGROUND: A limited amount of literature suggests that plasma leptin concentrations are reduced with habitual physical activity in men and non-pregnant women. We investigated the relationship between maternal physical activity and plasma leptin during early pregnancy. METHODS: The study population included 879 normotensive, non-diabetic pregnant women who reported physical activity type, frequency, and duration in early pregnancy. Plasma leptin, measured in blood samples collected <16 weeks gestation, were determined using enzyme immunoassays. Weekly duration (h/week) and energy expended on recreational physical activity [metabolic equivalent score (MET)-h/week] were categorized by tertiles among active women. Physical activity intensity was categorized as none, moderate (<6 MET) and vigorous (> or =6 MET). Differences in leptin concentrations across categories were estimated using linear regression procedures. RESULTS: Mean leptin was 5.8 ng/ml lower among active versus inactive women (P=0.001). Mean leptin was lower among women in the highest levels (>12.8 h/week) of time performing physical activity (-8.1 ng/ml, P<0.001) and energy expenditure (>70.4 MET-h/week) (-8.3 ng/ml, P=0.001) compared with inactive women. Leptin was inversely associated with the intensity of physical activity. CONCLUSIONS: Our findings are consistent with other reports suggesting an independent inverse relationship between habitual physical activity and leptin concentrations. Our findings extend the literature to include pregnant women.
Adult↗
Leptin, soluble leptin receptor and leptin gene polymorphism in relation to preeclampsia risk.
Few investigators have simultaneously evaluated leptin, soluble leptin receptor (SLR) and leptin gene polymorphisms in preeclampsia cases and controls. We examined these three biomolecular markers in 40 preeclampsia cases and 39 controls. Plasma leptin and SLR concentrations were determined using immunoassays. Genotype for the tetranucleotide repeat (TTTC)(n), polymorphism in the 3 -flanking region of the leptin gene was determined using PCR. Alleles of the polymorphism were characterized by size distributions [short repeats (class I); and long repeats (class II)]. Logistic regression was used to calculate odds ratios (OR) and 95 % confidence intervals (CI). Leptin concentrations were higher in our cases than in the controls (53.1 4.7 vs. 17.7+/-2.4 ng/ml, p<0.05). SLR concentrations were slightly lower in our patients than in the controls (25.7+/-1.9 vs. 29.1+/-1.1 ng/ml, p>0.05). Elevated leptin (? 14.5 ng/ml) was associated with a 3.8-fold (CI 1.0-14.4) increased risk; whereas low SLR (< 28.5 ng/ml) was associated with a 6.3-fold (CI 1.7-23.2) increased risk of preeclampsia. The I/II genotype was associated with a 3.8-fold increased risk of preeclampsia (OR=3.8; 95 % CI 0.8-18.0); and the II/II genotype was not observed among our cases (0 % vs. 33 % p<0.001). Larger studies would be needed to confirm and further clarify the relations between functional variants in the leptin gene and preeclampsia risk.
Adult↗
Relationship of maternal plasma leptin and risk of pre-eclampsia: a prospective study.
OBJECTIVE: We measured maternal plasma leptin concentrations in 55 women with pre-eclampsia and 487 normotensive women to determine whether elevated leptin concentrations were associated with the occurrence of pre-eclampsia. METHODS: Maternal blood samples were collected at 13 weeks' gestation, on average. Plasma leptin concentrations were determined using immunoassay. Logistic regression procedures were used to calculate odds ratios (OR) and 95% confidence intervals (95% CI). RESULTS: Leptin concentrations were 78% higher in cases than control subjects (median 34.6 vs. 19.5 ng/ml; p < 0.001). Relative to women with leptin concentrations of < 27.4 ng/ml, those with elevated leptin concentrations (> or = 27.4 ng/ml) experienced a 2.3-fold increased risk of pre-eclampsia (OR 2.3; 95% CI 1.1-4.6). We observed evidence of a strong linear component of trend in risk of pre-eclampsia with increasing maternal plasma leptin concentration. Each 10-ng/ml increase in leptin concentration was associated with a 30% increase in pre-eclampsia risk (OR 1.3; 95% CI 1.1-1.5). Overweight women with elevated leptin concentrations experienced the highest risk of pre-eclampsia (OR 6.4; 95% CI 3.1-13.2) as compared with lean women with no leptin elevations. CONCLUSION: Elevated plasma leptin concentration and maternal overweight status appear to be independently associated with an increased risk of pre-eclampsia.
Female↗
Correlates of recreational physical activity in early pregnancy.
OBJECTIVE: Despite the well-documented benefits of a physically active lifestyle, over 25% of American adults report that they never engage in regular recreational physical activity. Little is known about the determinants of physical activity among pregnant women. We investigated the predictors of physical activity in 386 normotensive pregnant women. METHODS: Participants provided information about the type, frequency and duration of each physical activity performed during the first 20 weeks of pregnancy. We calculated odd ratios (OR) for active compared with inactive women using logistic regression models. RESULTS: Approximately 61% of women reported participating in some regular physical activity during pregnancy. Walking, swimming, gardening and jogging were the most common activities. Physical activity as an adolescent (OR 4.0) and during the year before pregnancy (OR 48.9) were the strongest predictors of physical activity in pregnancy. Active women who continued to exercise during pregnancy decreased the average intensity of their exercise and the weekly duration of exercise compared with the year before pregnancy. Nulliparas were twice as likely to engage in physical activity as compared with multiparas. Education and income were positively related with physical activity. Non-White women were 40-60% less likely to engage in physical activity as compared with White women. Smokers were also less likely to engage in physical activity. High protein intake was positively associated with physical activity, while the opposite was true for high carbohydrate intake. CONCLUSIONS: The identification of determinants of physical activity in pregnancy has important implications for developing strategies aimed at promoting a physically active lifestyle among young women.
Adult↗
The opdB locus encodes the trypsin-like peptidase activity of Treponema denticola.
High levels of Treponema denticola in subgingival dental plaque are associated with severe periodontal disease. T. denticola, along with Porphyromonas gingivalis and Bacteroides forsythus, are the only cultivatable oral microorganisms that produce significant amounts of "trypsin-like" peptidase activity. The ability of subgingival plaque to hydrolyze N-alpha-benzoyl-DL-arginine-2-naphthylamide (BANA) is associated with high levels of one or more of these organisms. The purpose of this study was to identify the gene encoding trypsin-like activity in T. denticola and thus facilitate molecular-level studies of its potential role in disease. Using published peptide sequences of a T. denticola surface-associated oligopeptidase with BANA-hydrolyzing activity, we identified the gene, designated opdB, in an apparently noncoding region of the T. denticola genome unannotated contigs (11/2000; http://www.tigr.org). The opdB gene begins with a TTG start codon and encodes a 685-residue peptide with high homology to the oligopeptidase B family in prokaryotes and eukaryotes. An isogenic T. denticola opdB mutant was constructed by allelic replacement mutagenesis using an ermF/AM gene cassette. The mutant lacked BANA-hydrolyzing activity and had a slightly slower growth rate than the parent strain. This mutant will be used in future studies of interactions of T. denticola with host cells and tissue.
Alleles↗
The telemedicine network of the People's Liberation Army.
In the early 1990s, the People's Liberation Army began to establish a telemedicine network for the non-emergency health-care of the personnel of military units and their families, as well as local civilian patients. All data were transferred over the ordinary telephone network. All the stations were uniformly equipped with PCs containing videoconferencing cards. The network comprised 13 management centres and 208 teleconsultation stations. To evaluate the telemedicine service, we conducted a survey with written questionnaires and telephone interviews. The questionnaire was sent to the person responsible for each telemedicine station. A total of 187 questionnaires were returned, a response rate of 85%. The survey showed that 1503 teleconsultation sessions had been conducted for military as well as civilian patients during the 18-month study period, and 1708 static images had been transferred across the network during these sessions.
China↗
Association of plasma cortisol and chronic lung disease in preterm infants.
BACKGROUND: It has been suggested that preterm infants may have developmental immaturity of the hypothalamic-pituitary-adrenal axis, and that decreased cortisol response to stress increases risk of chronic lung disease (CLD) secondary to inflammatory lung injury. METHODS: To investigate the relationship between endogenous corticosteroid and CLD, we measured plasma cortisol during the first 28 days of life in a subset of neonates in the North American Thyrotropin-Releasing Hormone (TRH) Collaborative Trial. Analyses were performed on 314 infants, 24 to 32 weeks' gestation, whose mothers received 1 or 2 courses of antenatal corticosteroids plus TRH or placebo. RESULTS: Mean cortisol was 3.1 microg/dL (range: 0.1-17.9) at birth, reached maximal levels at 24 hours (19.4 microg/dL, range: 0.8-124.6), and decreased to 5.9 microg/dL (range: 0.2-24.7) at 14 to 28 days of age; levels during the first week were not associated with gestational age. The Clinical Risk Index for Babies (CRIB), a neonatal assessment tool that is correlated with risk of mortality, was positively associated with cortisol level on days 1 and 3 through 7. TRH versus placebo treatment did not influence cortisol levels at any time point. To examine the relationship between cortisol and adverse outcome of death or CLD at 36 weeks' postmenstrual age (CLD36), logistic regression models adjusting for known contributing clinical factors (gestational age and CRIB score) were fit. There was a statistically borderline negative association between median cortisol level at 3 to 7 days and CLD36. After adjusting for gestational age and CRIB score, the predicted probability of CLD36 was only minimally influenced by the cortisol concentration. CONCLUSION: In preterm infants, basal plasma cortisol concentration during the first week is a weak predictor for CLD36. Possible benefits as well as risks of supplemental, low-dose cortisol treatment of high-risk preterm infants remain to be determined.
Bronchopulmonary Dysplasia↗
Insoluble components of concentrated air particles mediate alveolar macrophage responses in vitro.
We sought to characterize the bioactive constituents of concentrated ambient air particles (CAPs) through correlation of alveolar macrophage (AM) biological responses (production of TNF, macrophage inflammatory protein (MIP-2), nitrite; cell viability) to components of particle samples. CAPs samples collected on different days showed a range of bioactivity and a strong correlation was found between AM cytokine release and increased AM light scatter, a flow cytometric measure of relative particle load. Evaluation of soluble and insoluble fractions of CAPs suspensions indicate that 1) most biological effects on AMs are mediated by insoluble components and certain particle adsorbed factors such as endotoxin; 2) the variable bioactivity of CAPs collected on different days arises primarily from differences in the relative proportion of insoluble and soluble mass present in particle suspensions; and 3) the activation state of the AM influences which insoluble components are most bioactive. Use of endotoxin neutralizing agents (e.g., polymyxin-B) showed particle-adsorbed endotoxin in CAPs suspensions causes activation of normal (control) AMs while other (nonendotoxin) components are predominantly responsible for the enhanced cytokine release observed by primed AMs incubated with CAPs. The AM biological response did not correlate with any of a panel of elements quantified within insoluble CAPs samples (Al, Cd, Cr, Cu, Fe, Mg, Mn, Ni, S, Ti, V). These data demonstrate an important role for cell activation and phagocytosis of insoluble particulate matter in the response of AMs to CAPs suspensions.
Air Pollutants↗
An optimized set of human telomere clones for studying telomere integrity and architecture.
Telomere-specific clones are a valuable resource for the characterization of chromosomal rearrangements. We previously reported a first-generation set of human telomere probes consisting of 34 genomic clones, which were a known distance from the end of the chromosome ( approximately 300 kb), and 7 clones corresponding to the most distal markers on the integrated genetic/physical map (1p, 5p, 6p, 9p, 12p, 15q, and 20q). Subsequently, this resource has been optimized and completed: the size of the genomic clones has been expanded to a target size of 100-200 kb, which is optimal for use in genome-scanning methodologies, and additional probes for the remaining seven telomeres have been identified. For each clone we give an associated mapped sequence-tagged site and provide distances from the telomere estimated using a combination of fiberFISH, interphase FISH, sequence analysis, and radiation-hybrid mapping. This updated set of telomeric clones is an invaluable resource for clinical diagnosis and represents an important contribution to genetic and physical mapping efforts aimed at telomeric regions.
Chromosomes, Artificial, Yeast↗
Suppression of X-ray-induced chromatid breaks in human tumor cells by introduction of normal chromosome 4.
Human tumor cells in culture frequently show an infinite lifespan and are characterized by an abnormally high frequency of chromatid breaks after x-irradiation during G(2) phase of the cell cycle. This abnormally high frequency of persistent chromatid breaks results from deficient repair of the radiation-induced DNA damage. In three of four tumor cell lines, addition of a single human chromosome 4 from normal cells by microcell fusion resulted in efficient repair as evidenced by suppression of radiation-induced chromatid breaks to the level in normal cells. With respect to senescence-related gene (s), two of these four tumor cell lines belonged to complementation group A and one each to groups C and D. Chromosome 4 restored DNA repair efficiency in only one of the two tumor cell lines of complementation group A. These results suggest that chromosome 4 carries a DNA repair gene or gene(s) that complement the repair deficiency in three of these four tumor lines. Furthermore, the gene(s) involved in cellular senescence on chromosome 4 appear to differ from the gene(s) for repair of radiation-induced DNA damage during G(2).
Cell Division↗
Alveolar macrophage cytokine production in response to air particles in vitro: role of endotoxin.
The interaction of air particles and alveolar macrophages (AMs) may result in the release of proinflammatory cytokines. Normal mouse AMs were treated with concentrated air particle (CAPs) suspensions in vitro. After 5 h, cytokine release [macrophage inflammatory protein-2 (MIP-2) and tumor necrosis factor-alpha (TNF-alpha)] and phagocytosis of ambient air particles were measured. CAPs samples collected from urban air (Boston) on different days were used. The CAPs samples and their soluble and solid components caused significant MIP-2 and TNF-alpha production. Variability in the potency of samples collected on different days was observed. Trace endotoxin was measured in CAPs samples (EU/mg: 2.3 +/- 0.7, mean +/- SE, n = 10). A majority of biologic activity (cytokine induction) and endotoxin content was associated with the solid components. Neutralization of endotoxin by polymyxin B abrogated >80% of TNF-alpha induction by CAPs samples, but inhibited MIP-2 production by only approximately 40%. The trace endotoxin present in CAPs caused much more MIP-2 production than predicted by concentration alone (28 +/- 8-fold increase, n = 9), indicating synergistic interaction with other AM-activating components of the particles. Data suggest that low levels of endotoxin may interact with air particles to activate lung macrophages.
Air Pollutants↗
Trapping of bead-based reagents within microfluidic systems: on-chip solid-phase extraction and electrochromatography
A 330-pL chromatographic bed was fabricated on a glass substrate as part of an electroosmotically pumped microfluidic system. Two weirs within a sample channel formed a cavity in which octadecylsilane (ODS) coated silica beads (1.5-4 microns diameter) were trapped. ODS beads were mobilized into and out of the cavity using electroosmotic flow through a bead-introduction channel which accessed the cavity. This procedure allowed the beads in the cavity to be repeatedly exchanged. A 1 nM solution of a nonpolar analyte (BODIPY 493/503) in buffer was loaded onto the beads for different lengths of time using an electroosmotic flow of 1.2 nL/s. The material retained on the ODS phase was then eluted by electroosmotic flow of acetonitrile with a concentration enhancement of up to 500 times. Capillary electrochromatography was conducted using a similar device. BODIPY and fluorescein were loaded onto a 200-micron-long chromatographic bed and then separated in an isocratic CEC run with an acetonitrile/buffer mobile phase. Complete separation was achieved in less than 20 s with a 2-micron plate height.
Journal Article↗
An enhanced microfluidic chip coupled to an electrospray Qstar mass spectrometer for protein identification.
The combination of microfabricated fluidic systems (muFAB) and electrospray mass spectrometers (ESI-MS) will provide multiplexed and integrated analytical systems for proteins and other biomolecules. Implementation of this novel approach requires the development of robust and user-friendly muFAB devices. Here, we present new approaches that improve the robustness, user friendliness and performance of muFAB devices coupled to MS. First, we present the development of a convenient mount to connect a muFAB device to the ESI-MS and the incorporation of filters in the reservoirs and exit of the muFAB. This mount facilitates interfacing and significantly reduces the chemical noise observed by the MS. Furthermore, we demonstrate improvements in sample handling and delivery by using either a nonaqueous electrolyte or a cationic coating on the surfaces in the muFAB device and transfer capillary. These improvements are applied to protein analysis by continuous infusion of proteolytic digests.
Animals↗
Detection of chromosomal aberrations by a whole-genome microsatellite screen.
Chromosomal aberrations are a common cause of multiple anomaly syndromes that include developmental and growth retardation. Current microscopic techniques are useful for the detection of such aberrations but have a limit of resolution that is above the threshold for phenotypic effect. We hypothesized that a genomewide microsatellite screen could detect chromosomal aberrations that were not detected by standard cytogenetic techniques in a portion of these individuals. To test this hypothesis, we performed a genomewide microsatellite screen of patients, by use of a currently available genetic-marker panel that was originally designed for meiotic mapping of Mendelian traits. We genotyped approximately 400 markers on 17 pairs of parents and their children who had normal karyotypes. By using this approach, we detected and confirmed two cases of segmental aneusomy among 11 children with multiple congenital anomalies. These data demonstrate that a genomewide microsatellite scan can be used to detect chromosomal aberrations that are not detected by microscopic techniques.
Abnormalities, Multiple↗
Flat panel detector-based cone-beam volume CT angiography imaging: system evaluation.
Preliminary evaluation of recently developed large-area flat panel detectors (FPDs) indicates that FPDs have some potential advantages: compactness, absence of geometric distortion and veiling glare with the benefits of high resolution, high detective quantum efficiency (DQE), high frame rate and high dynamic range, small image lag (< 1%), and excellent linearity (approximately 1%). The advantages of the new FPD make it a promising candidate for cone-beam volume computed tomography (CT) angiography (CBVCTA) imaging. The purpose of this study is to characterize a prototype FPD-based imaging system for CBVCTA applications. A prototype FPD-based CBVCTA imaging system has been designed and constructed around a modified GE 8800 CT scanner. This system is evaluated for a CBVCTA imaging task in the head and neck using four phantoms and a frozen rat. The system is first characterized in terms of linearity and dynamic range of the detector. Then, the optimal selection of kVps for CBVCTA is determined and the effect of image lag and scatter on the image quality of the CBVCTA system is evaluated. Next, low-contrast resolution and high-contrast spatial resolution are measured. Finally, the example reconstruction images of a frozen rat are presented. The results indicate that the FPD-based CBVCT can achieve 2.75-lp/mm spatial resolution at 0% modulation transfer function (MTF) and provide more than enough low-contrast resolution for intravenous CBVCTA imaging in the head and neck with clinically acceptable entrance exposure level. The results also suggest that to use an FPD for large cone-angle applications, such as body angiography, further investigations are required.
Angiography↗
Chemoprevention of aflatoxin B1-initiated and carbon tetrachloride-promoted hepatocarcinogenesis in the rat by green tea.
Chemoprevention of hepatocarcinogenesis by green tea (GT) has been examined in young male Fischer rats fed AIN-76A diet with aflatoxin B1 (AFB1) and CCl4 as the initiator and promoter, respectively. Animals were administered AFB1 (0.25 mg/kg body wt ip) twice a week for 2 weeks, and 2 weeks later, CCl4 was injected (0.8 ml/kg body wt ip) once per week for 11 weeks. Rats given 0.5% GT in their drinking water before and during initiation (0-4 wk) or during promotion (6-16 wk) or throughout the experimental period were sacrificed 24 hours after the last dose of CCl4. Bromodeoxyuridine incorporation as a measure of cell proliferation and glutathione S-transferase placentalform- and gamma-glutamyl transpeptidase-positive hepatic foci were analyzed by histochemical methods. Feeding of GT during initiation or promotion inhibited the number of glutathione S-transferase placental form- and gamma-glutamyl transpeptidase-positive hepatic foci by 30-40% and the area and volume by 50%. GT treatment throughout the period inhibited the number of both types of hepatic foci by 60% and the area and volume by 75-80%. Cell proliferation was inhibited 35% by GT given during promotion, whereas inhibition was 65% when GT was given during initiation or throughout the period. These results indicate that GT feeding inhibits initiation and promotion steps of AFB1 hepatocarcinogenesis and that the inhibition of cell proliferation is responsible for the inhibition of promotion.
Aflatoxin B1↗