Biomedical subjects

Q Zhang

Publications and source records attributed to Q Zhang.

At least 613 records · Page 34Linked to original sources

PubMed1997

Crustacean hyperglycaemic hormone in the nervous system of the primitive crustacean species Daphnia magna and Artemia salina (Crustacea: Branchiopoda).

Crustacean hyperglycaemic hormone-immunoreactive neuronal systems are detected in the central and peripheral nervous systems of two entomostracan crustaceans, Daphnia magna and Artemia salina, by immunocytochemistry using specific antisera against crustacean hyperglycaemic hormones of the decapod crustaceans Orconectes limosus and Carcinus maenas. In D. magna, four small putative interneurones are detected in the brain. In the thorax, ten bipolar peripheral neurones are stained by both antisera. They are obviously segmental homologues with centrally projecting axons that form interdigitating varicose fibres and terminals in putative neurohaemal areas next to the surface of the anterior part of the thoracic ganglia. Similar immunopositive neurones occur both in the central and peripheral nervous systems of A. salina. A total of five groups of neurones occur in the protocerebrum, the deutocerebrum and the mandibular ganglion. Some of the protocerebral neurones are bipolar and project to the dorsal frontal organ. A single pair of peripheral multipolar neurones in the maxillary segment projects centrally into the ventral nerve cord and innervates unidentified somatic muscles and tissues in the maxillary and the first appendage segments. None of the brain neurones in both species show similarities to decapod X-organ sinus gland neurosecretory neurones. Chromatography of brain extracts of D. magna combined with immunodot blotting revealed two strongly immunoreactive fractions at retention times close to that of the crustacean hyperglycaemic hormone of crayfish. Moreover, preabsorption controls suggest that the cross-reacting peptides of D. magna and A. salina are structurally closely related to those of decapods.

Animals↗

PubMed1997

Evaluation of an extracorporeal membrane oxygenation system using a nonporous membrane oxygenator and a new method for heparin coating.

A new heparin binding method was applied to a miniature extracorporeal membrane oxygenation (ECMO) system with a nonporous membrane oxygenator (the priming volume, 45 mL; the membrane surface area, 0.4 m2; maximal flow rate, 2 L/min) that is resistant to plasma leakage. The authors evaluated the stability of the immobilized heparin in vitro and the feasibility of this system in animals. Samples of hollow fibers and tubing were rinsed at 40 degrees C for 4 days in normal saline, Ringer's lactate, and 1 mol/L NaCl solution. Heparin activities on hollow fibers after rinsing were 99 +/- 2.3% (mean +/- SD), 96 +/- 3.9%, and 93 +/- 2.0% of the control in each solution, while those of the tubing were 87 +/- 4.1%, 86 +/- 3.1%, and 76 +/- 8.6%, respectively. Veno-arterial ECMO using this heparin-coated system was performed on five beagles (8 to 12 kg) for 10 hours. Neither major thrombus formation nor plasma leakage was detected during the procedure in spite of a low flow rate (300 mL/min) and a reduced activated clotting time (mean, 128 seconds). Platelets decreased to 52% of the control (P < .01) at 1 hour, but no progressive decrease was seen thereafter. Antithrombin-III decreased (P < .01) and thrombin/antithrombin III complex increased (P < .05 at 4 hours and P < .01 at 6, 8, and 10 hours) during bypass, but the changes of fibrinogen and fibrinopeptide A were not significant. Fibrinogen/fibrin degeneration products, fibrinopeptide B beta 15-42, and plasma-free hemoglobin levels did not rise significantly. O2 transfer of the oxygenators at a flow rate of 300 mL/min were 12.3 +/- 0.4 mL/min at 30 minutes, 14.3 +/- 1.2 mL/min at 5 hours, and 14.7 +/- 1.7 mL/min at 10 hours (no statistical difference). Histological examination of the brains and the kidneys showed no evidence of thromboembolic sequela in any of the animals. These results suggest that this new system is a promising device for long-term ECMO in which the amount of systemic heparinization can be reduced with the minimal possibility of plasma leakage.

Animals↗

PubMed1997

Beta 2-microglobulin and calnexin can independently promote folding and disulfide bond formation in class I histocompatibility proteins.

Class I histocompatibility proteins fold and assemble with beta 2-microglobulin (beta 2m) into heterodimers before binding short peptides in the endoplasmic reticulum. Here, we show that class I proteins rapidly form disulfide bonds, and that the process is highly reversible in Daudi cells lacking beta 2m. Three distinct class I protein conformations are present in equal amounts in these cells, each associated with the molecular chaperone calnexin. When binding of calnexin is inhibited by the glucosidase inhibitor castanospermine, fully oxidized class I proteins are no longer detected, suggesting that calnexin is required for completion of folding. However, in Daudi cells transfected to express beta 2m, castanospermine decreases only slightly the levels of fully oxidized class I proteins, indicating that folding is much less dependent on calnexin in the presence of beta 2m. Furthermore, calreticulin, a chaperone with functional similarities to calnexin, associates with class I molecules in beta 2m-positive cells. but not in Daudi cells, consistent with completion of folding and disulfide bond formation of class I heavy chains before binding to calreticulin occurs. This study demonstrates that calnexin and beta 2m can function independently to promote folding of class I heavy chains prior to formation of stable class I dimers.

Burkitt Lymphoma↗

PubMed1997

Pulmonary phospholipid saturation increases with glucocorticoid receptor mRNAs in late gestation but not due to labor in the fetal rhesus monkey.

We report here changes in abundance of pulmonary cytosolic phospholipase A2 (cPLA2) and glucocorticoid receptor (GR) mRNAs and phospholipid (PL) fatty acids (FA) with gestational age, in either spontaneous or androstenedione-induced premature labor for 15 fetal rhesus monkeys and 1 neonate. Pulmonary RNA and lipids were extracted from the lungs of the rhesus monkeys, gestational ages ranging from 140 days to term. Northern hybridization analysis was performed for both cPLA2 and GR mRNAs. The results demonstrated the transcript of the cPLA2 constantly expressed and that of GR increased gradually in the lungs during the gestational stages studied. Phosphatidylcholine (PC), phosphatidylglycerol (PG) and phosphatidylinositol (PI) were separated by thin layer chromatography and the fatty acid composition in these PL was quantified by gas chromatography (GC). Regression analysis demonstrated that the expression of GR, mRNAs increased significantly with gestational age (P < 0.01). Furthermore, the level of GR mRNA is significantly correlated with that of cPLA2, with Pearson correlation coefficient of 0.83 (P < 0.01). The PC palmitate percentage increased significantly with gestational age (P < 0.01), while the PC unsaturation index and total polyunsaturated FA decreased during late gestation (P < 0.01). Changes in PG FA with gestational age were similar to those in PC, while PI FA did not change with gestational age. There was no effect of either spontaneous or induced labor on mRNA levels of cPLA2 and GR or the FA composition of pulmonary PL studied. We conclude that the pulmonary PL FA compositions are under developmental control.

Animals↗

PubMed1997

Copia-like retrotransposons in rice: sequence heterogeneity, species distribution and chromosomal locations.

Degenerated oligonucleotide primers were used to amplify, clone, and analyze sequence heterogeneity and chromosomal distribution of 23 PCR fragments corresponding to the reverse transcriptase domain of copia-like retrotransposons in rice. Of the 23 fragments 22 could be aligned by their deduced amino acid sequences and were divided into 6 groups according to the phylogenetic and Southern blot analyses. Amino acid sequence differences among the 22 aligned fragments ranged from 1 to 64%. Southern blot analysis of 10 rice accessions including indica, japonica and common wild rice, using these 23 fragments as probes, showed that copia-like retrotransposons were present in moderate to high copy numbers in all the rice genome although the exact copy number cannot be determined. The major difference revealed by southern analysis is a differentiation between the four indica varieties as one group and the four japonica varieties and the two wild rice accessions as another group. Polymorphisms were also detected among the indica and japonica varieties by major bands and repeatable minor bands. Five hybridization bands were mapped to chromosomes 3, 4, 8, and 9, respectively. All the five bands were inherited in a dominant Mendelian fashion and were not allelic with each other, indicating that the same element did not reside on the same location in different rice accessions. No transcript of the copia-like reverse transcriptase was detected on northern blot. The results suggest that the sequence heterogeneity and distributional variability of retrotransposons may be one of contributory factors causing genetic diversity in rice.

Amino Acid Sequence↗

PubMed1997

Autologous bone marrow mixed with HLA-haploidentical allogeneic marrow transplantation for treatment of patients with malignant blood diseases.

We have previously demonstrated that syngeneic marrow mixed with H-2 haploidentical marrow transplantation could provide not only protection against graft-versus-host disease (GVHD) but also anti-leukemic (GVL) effects in mice. In the present studies, we report clinical observations using autologous marrow mixed with HLA-haploidentical allogeneic marrow transplantation for treatment of patients with malignant blood diseases. Sixteen cases, including 12 with acute leukemia and four with advanced malignant lymphoma, were treated by autologous marrow, which was purged in vitro by hyperthemia (42.5 degrees C for 70 min) following incubation for 5 days with interleukin 2 (IL-2) in liquid culture and mixed with HLA haploidentical marrow cells from their sibling or parent. Acute GVHD was not observed in any patient after transplantation. Hematological rescue in the clinical setting was demonstrated in all cases but one who died early from hepatic veno-occlusive disease (VOD). Five cases who were transplanted at the time of CR2 or CR3 and in advanced phase of lymphoma, relapsed 4 to 7 months after transplantation. The relapse rate was 31.3%. None of eight patients who received allogeneic BMT within 2 h after ABMT relapsed with median follow-up of 12 months and two of them died from procedure-related complications. Seven cases are still alive and disease-free with a median follow-up of 12 months. Mixed chimerism was found in 3/6 cases, who had different sex donors, by analysis of sex chromosomes. These results show that mixed transplantation is a safe, effective and new approach to treating patients with malignant tumors. In order to detect the effects of GVL, studies are now in progress in our clinic.

Adult↗

PubMed1997

ETS-1 induces increased expression of erythroid markers in the pluripotent erythroleukemic cell lines K562 and HEL.

Members of the ETS gene family are known to be expressed in hematopoietic tissues and cell lines, and there is increasing evidence that ETS proteins may play a role in normal hematopoietic cell development. We demonstrate that ETS-1 can contribute to the development of an erythroid phenotype in vitro. The pluripotent erythroleukemic K562 and HEL cell lines express messages for a number of ETS genes, but only c-ETS-1 levels are elevated in response to treatment with hemin or cytosine arabinofuranoside (Ara-C), agents which induce erythroid differentiation. Furthermore, ETS-1 antisense oligonucleotides inhibit hemoglobinization of cells treated with Ara-C or hemin, and K562 and HEL cells infected with retrovirus expressing the c-ETS-1 gene exhibit a significant increase in erythroid character (as indicated by benzidine staining for hemoglobin (Hb) and surface marker analysis), a dramatic increase in responsiveness to hemin or Ara-C, and a decreased rate of proliferation (20-40% of control rates). In contrast, infection with virus expressing ETS-2 or vector sequences only causes no detectable changes in the proliferation or erythroid character of either the HEL or K562 cell lines. These data indicate a role for ETS-1 in erythroid differentiation.

Cell Differentiation↗

PubMed1997

Mutations at the lipoprotein lipase gene locus in subjects with diabetes mellitus, obesity and lipaemia.

1. The common association of obesity, diabetes mellitus and hyperlipidaemia may have a primary aetiological basis. Insulin resistance has been postulated as a possible cause, but defects in the plasma transport of triacylglycerol or fatty acids could also be primary determinants. 2. We have therefore studied 18 patients with diabetes mellitus, obesity and severe hypertriglyceridaemia for defects of a key protein involved in the clearance of plasma triacylglycerols, lipoprotein lipase. 3. DNA was prepared from leucocytes of 18 patients with the above syndrome, and exons encoding lipoprotein lipase were amplified by PCR. The products were sequenced using the dideoxy chain-termination method. 4. Eight of the subjects were found to possess genetic variants at the lipoprotein lipase gene locus. These were: (a) G579-->A, V108V; (b) G818-->A, G188E; (c) C829-->T, R192; (d) A1127-->G, N291S; (e) C1308-->G, F351L; (f) C1338-->A, T361T; and (g) C1595-->G, S447. Three of these, (c), (e) and (f), have not hitherto been described. Variant (f), appears to be a population polymorphism whose allele frequency in normolipidaemic diabetics was found to be 0.12 (162 chromosomes studied). The others are all rare at frequencies of < 0.01 and may contribute to the phenotype by impairing clearance of plasma triacylglycerols. 5. We conclude that genetic variants at the lipoprotein lipase locus occur commonly in subjects with this syndrome (four out of 18 subjects with probably functional mutants) and may affect the individual's response to obesity and diabetes mellitus for the development of lipaemia.

Adult↗

PubMed1997

Lysophosphatidic acid and microtubule-destabilizing agents stimulate fibronectin matrix assembly through Rho-dependent actin stress fiber formation and cell contraction.

Fibronectin (FN) matrix assembly is a cell-dependent process mediated by cell surface-binding sites for the 70-kDa amino-terminal region of FN. We have shown recently that lysophosphatidic acid (LPA) is a stimulator of FN matrix assembly. Disruption of microtubules has been shown to mimic some of the intracellular effects of LPA including the formation of actin stress fibers and myosin light chain phosphorylation. We compared the effects of microtubule disruption and LPA on FN binding and actin cytoskeleton organization. The disruption of microtubules by nocodazole or vinblastine increased FN binding to adherent cells. The modulation of binding sites was rapid, dynamic, and reversible. Enhanced binding was due to increases in both the number and affinity of binding sites. These effects are similar to the effects of LPA on FN binding. Binding induced by nocodazole was inhibited by the microtubule-stabilizing agent Taxol but not by pretreatment with a concentration of phospholipase B that totally abolished the stimulatory effect of LPA. Fluorescence microscopy revealed a close correlation among actin stress fiber formation, cell contraction, and FN binding. Blockage of the small GTP binding protein Rho or actin-myosin interactions inhibited the effects of both nocodazole and LPA on FN binding. These observations demonstrate that Rho-dependent actin stress fiber formation and cell contraction induce increased FN binding and represent a rapid labile way that cells can modulate FN matrix assembly.

Animals↗

PubMed1997

Advances in statistical methods to map quantitative trait loci in outbred populations.

Statistical methods to map quantitative trait loci (QTL) in outbred populations are reviewed, extensions and applications to human and plant genetic data are indicated, and areas for further research are identified. Simple and computationally inexpensive methods include (multiple) linear regression of phenotype on marker genotypes and regression of squared phenotypic differences among relative pairs on estimated proportions of identity-by-descent at a locus. These methods are less suited for genetic parameter estimation in outbred populations but allow the determination of test statistic distributions via simulation or data permutation; however, further inferences including confidence intervals of QTL location require the use of Monte Carlo or bootstrap sampling techniques. A method which is intermediate in computational requirements is residual maximum likelihood (REML) with a covariance matrix of random QTL effects conditional on information from multiple linked markers. Testing for the number of QTLs on a chromosome is difficult in a classical framework. The computationally most demanding methods are maximum likelihood and Bayesian analysis, which take account of the distribution of multilocus marker-QTL genotypes on a pedigree and permit investigators to fit different models of variation at the QTL. The Bayesian analysis includes the number of QTLs on a chromosome as an unknown.

Bayes Theorem↗

PubMed1997

Determination of the volume activity concentration of alpha artificial radionuclides with alpha spectrometer.

This paper introduces a method to determine the volume activity concentration of alpha and/or beta artificial radionuclides in the environment and radon/thoron progeny background-compensation based on a Si surface-barrier detector. By measuring the alpha peak counts of 218Po and 214Po in two time intervals, the activity concentration of 218Po, 214Pb and 214Bi aerosol particles were determined; meanwhile, the total beta count of 214Pb and 214Bi aerosols was also calculated from their decay scheme. With the average equilibrium factor of thoron progeny in general environment, the alpha and beta counts of thoron progeny were approximately evaluated by 212Po alpha peak counts. The alpha count of transuranic aerosols was determined by subtracting the trail counts of radon/thoron progeny alpha peaks. The total count of beta artificial radionuclides was determined by subtracting the beta counts of radon/thoron progeny aerosol particles. In our preliminary experiments, if the radon progeny concentration is less than 15 Bq m(-3), the lower limit of detection of transuranics concentration is less than 0.1 Bq m(-3). Even if the radon progeny concentration is as high as 75 Bq m(-3), the lower limit of detection of total beta activity concentration of artificial nuclides aerosols is less than 1 Bq m(-3).

Aerosols↗

PubMed1997

A specific method for the measurement of tacrolimus in human whole blood by liquid chromatography/tandem mass spectrometry.

Tacrolimus (FK 506) measurement by immunoassays in clinical samples of organ transplant patients often lacks a specific reference method. A method combining liquid chromatography (LC) with tandem mass spectrometry (MS/MS) was developed to quantify tacrolimus in whole blood. Liquid-liquid extraction was performed on 1 ml of sample before narrow-bore LC/MS/MS analysis. Ascomycin was used as an internal standard. The standard curve was composed of seven points ranging from 1 to 50 micrograms/l (average r2 = 0.9999). Limits of detection and quantitation were 0.25 and 0.75 microgram/l, respectively. Imprecision was < 5% across the therapeutic range. Tacrolimus recovery averaged 62%. The most abundant metabolites detected in clinical samples were 13-O- and 15-O-demethyl tacrolimus. This method was used in a comparison study with a microparticle enzyme immunoassay (MEIA): MEIA = 1.03 LC/MS/MS -0.084 (microgram/l), (Sy/x = 1.43), r2 = 0.933. With its high sensitivity and specificity, this LC/MS/MS method presents a good reference method for immunoassay evaluation as well as a valuable tool for metabolism studies.

Chromatography, High Pressure Liquid↗

PubMed1997

Relationship between the mucosal production of reactive oxygen radicals and density of Helicobacter pylori in patients with duodenal ulcer.

OBJECTIVE: To investigate the associations between the mucosal production of reactive oxygen radicals (RORs) in the gastric antrum and duodenum, Helicobacter pylori density and duodenal ulcer (DU). PATIENTS: Forty-seven endoscoped patients, comprising 22 with DU and 25 non-ulcer subjects, were included in the study. METHODS: Antral and duodenal biopsies were taken for histology, Helicobacter pylori culture and measurement of chemiluminescence. Biopsies were homogenized and cultured on Columbia blood agar plate. Colonies of H. pylori were counted and bacterial density expressed as colony-forming units (cfu)/mg of biopsy. Chemiluminescence was measured by luminometry and the results expressed as millivolt (mV)/min/mg of biopsy, after subtraction of background count. RESULTS: Thirty-one of 47 (66%) patients had antral H. pylori and 6/47 (12.8%) had proven duodenal colonization. Increased chemiluminescence (median (interquartile)) was found in H. pylori-infected patients compared to those without H. pylori in antral (90.0 (26.0, 249.0) vs. 7.0 (0.0, 10.0), P<0.001) and duodenal mucosa (22.0 (10.0, 100.0) vs. -2.5 (-10.0, 0.0) P<0.001). A positive correlation was found between antral H. pylori density and chemiluminescence response in both the antrum (r=0.77) and duodenum (r=0.52). DU patients showed an increased chemiluminescence compared to those non-ulcer subjects with or without H. pylori infection in antrum (163.5 (44.5, 297.8) vs. 33.0 (8.7, 168.0) (P=0.046) vs. 2.7 (0.1, 10.0), P<0.01) and duodenum (45.0 (17.5, 100.0) vs. 15.0 (-1.25, 22.5) vs. -2.5 (-10, 0.0), P<0.01). CONCLUSION: Increased production of RORs in the antrum and duodenum was found to be related to antral H. pylori density and associated with duodenal ulceration. The association between antral H. pylori and ROR release in the duodenum may be important in the pathogenesis of duodenal ulceration.

Biopsy↗

PubMed1997

Differential expression of the multigene family encoding the soybean mitochondrial alternative oxidase.

The alternative oxidase (AOX) of the soybean (Glycine max L.) inner mitochondrial membrane is encoded by a multigene family (Aox) with three known members. Here, the Aox2 and Aox3 primary translation products, deduced for cDNA analysis, were found to be 38.1 and 36.4 Kd, respectively. Direct N-terminal sequencing of partially purified AOX from cotyledons demonstrates that the mature proteins are 31.8 and 31.6 KD, respectively, implying that processing occurs upon import of these proteins into the mitochondrion. Sequence comparisons show that the processing of plant AOX proteins occurs at a characteristic site and that the AOX2 and AOX3 proteins are more similar to one another than to other AOX proteins, including soybean AOX1. Transcript analysis using a polymerase chain reaction-based assay in conjunction with immunoblot experiments indicates that soybean Aox genes are differentially expressed in a tissue-dependent manner. Moreover, the relative abundance of both Aox2 transcripts and protein in cotyledons increase upon greening of dark-grown seedlings. These results comprehensively explain the multiple AOX-banding patterns observed on immunoblots of mitochondrial proteins isolated from various soybean tissues by matching protein bands with gene products.

Amino Acid Sequence↗

PubMed1997

Localized reversible frameshift mutation in an adhesin gene confers a phase-variable adherence phenotype in mycoplasma.

The variable adherence-associated (Vaa) antigen of Mycoplasma hominis is an abundant surface lipoprotein adhesin that may mediate important interactions of this wall-less prokaryotic pathogen with the human host. Extensive mutational variation of Vaa size, as well as sequence and antigenic divergence, has been described previously. Using a series of clonal isolates representing an isogenic lineage of variants oscillating in Vaa expression, Vaa is further shown in this study to undergo high-frequency phase variation in expression, which correlated precisely with the ability of M. hominis to adhere to cultured human cells. Although no DNA rearrangements or sequence differences in the 5' regions flanking vaa alleles were detected between Vaa+ and Vaa variants, intragenic vaa sequences from this lineage revealed an oscillating mutation involving a single nucleotide deletion/insertion in a short tract of adenine residues near the 5' end of the mature Vaa coding sequence, which created a translational frameshift resulting in either a complete Vaa ORF or an in-frame UAG stop codon immediately downstream of the poly-A tract. Evidence for the occurrence of this high-frequency frameshift mutation in vivo was obtained from analysis of PCR-generated vaa sequences amplified from the joint synovial fluid of a patient with M. hominis-associated arthritis, which indicated that Vaa phase variation occurs during M. hominis infection in the natural host. These results identify a distinctive frameshift mutator element in the vaa gene that governs M. hominis adherence and highlight the importance of mutational alteration of primary gene products on the mycoplasma surface as a means of generating and maintaining functional diversity in the host.

Adhesins, Bacterial↗

PubMed1997

Binding of a novel host factor to the pT181 plasmid replication enhancer.

Replication enhancers are cis-acting genetic elements that stimulate the activity of origins of DNA replication. The enhancer found in plasmid pT181 of Staphylococcus aureus, called cmp, functions at a distance of 1 kb from the origin of DNA replication to stimulate the interaction between the replication initiation protein and the origin. DNA encoding cmp-binding activity was isolated by screening an expression library of S. aureus DNA in Escherichia coli, and a novel gene, designated cbf1, was identified. The cbf1 locus codes for a polypeptide of 313 amino acid residues (cmp-binding factor 1 [CBF1]; Mr = 35,778). In its COOH-terminal region, the protein sequence contains the helix-turn-helix motif common to many DNA binding proteins that usually bend DNA. The specificity of CBF1 binding for cmp was demonstrated by affinity chromatography using cmp DNA and by competition binding studies. DNase I footprinting analysis of the CBF1-cmp complexes revealed DNase I-hypersensitive sites in phase with the helical periodicity of DNA, implying that CBF1 increases distortion of the intrinsically bent cmp DNA.

Amino Acid Sequence↗

PubMed1997

Partitioning of lung tissue response and inhomogeneous airway constriction at the airway opening.

During a bronchial challenge, much of the observed response of lung tissues is an artifactual consequence of inhomogeneous airway constriction. Inhomogeneities, in the sense of time constant inequalities, are an inherently linear phenomenon. Conversely, if lung tissues respond to a bronchoagonist, they become more nonlinear. On the basis of these distinct responses, we present an approach to separate real tissue changes from airway inhomogeneities. We developed a lung model that includes airway inhomogeneities in the form of a continuous distribution of airway resistances and nonlinear viscoelastic tissues. Because time domain data are dominated by nonlinearities, whereas frequency domain data are most sensitive to inhomogeneities, we apply a combined time-frequency domain identification scheme. This model was tested with simulated data from a morphometrically based airway model mimicking gross peripheral airway inhomogeneities and shown capable of recovering all tissue parameters to within 15% error. Application to our previously measured data suggests that in dogs during histamine infusion 1) the distribution of airway resistances increases widely and 2) lung tissues do respond but less so than previously reported. This approach, then, is unique in its ability to differentiate between airway and tissue responses to an agonist from a single broadband measurement made at the airway opening.

Airway Resistance↗

PubMed1997

Association of natural killer cell activity with serum IgE.

Association of natural killer (NK) cell activity (NKCA) or NK cell subsets with total IgE or antigen-specific IgE in serum were studied among 66 healthy non-allergic males. NKCA was determined by using 61Cr release assay and NK subsets were counted usings surface antigens (CD16, CD57) in peripheral blood mononuclear cells. NKCA was associated mainly with the frequency of a CD16+,CD57- subset. When the subjects were classified into three groups according to total IgE values in serum (grade 0: IgE < 10 IU/ml; grade 1: IgE 10-400 IU/ml; grade 2: IgE > 400 IU/ml), one-way analysis of variance of NKCA showed that the grades of total IgE were significantly associated with increasing NKCA. In addition, NKCA in the grade 0 group was significantly lower than that in the grade 2 group and than a mixture of grade 1 group and grade 2 group. A similar finding was not observed between NKCA and RAST for specific IgE against mites. Therefore, NKCA may be related to total IgE level in serum.

Adult↗