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971.
972.
973.
Shim YK Vogt RF Middleton D Abbasi F Slade B Lee KY Marti GE 《Cytometry. Part B, Clinical cytometry》2007,72(5):344-353
BACKGROUND: Monoclonal B-cells can be detected in the peripheral blood of some adults without B-cell malignancies, a condition recently termed monoclonal B-cell lymphocytosis (MBL). The risk of individuals with MBL progressing to a B-cell malignancy is unknown. Polyclonal B-cell lymphocytosis (PCBL) has not been systematically studied in the general population. METHODS: We obtained lymphocyte subset counts on 1,926 residential adults aged 40-76 years in a series of environmental health studies between 1991 and 1994. We then conducted two follow-ups in 1997 and 2003 on consenting participants with B-cell lymphocytosis, which included nine participants with MBL. To ascertain the clinical implications of MBL, we reviewed medical records and death certificates. RESULTS: The overall prevalence of MBL was 0.57% (11/1,926): nine cases at baseline and two additional cases identified at follow-up. Two (19%) MBL cases subsequently developed a B-cell malignancy; MBL persisted in the remaining nine cases (81%). All PCBL cases where no clone emerged regressed to normal B-cell counts over the follow-up period. MBL was significantly more frequent in residents near a hazardous waste site than in the control populations (age-adjusted OR 6.2; 95%CI 1.1-36.2). CONCLUSION: MBL confers an elevated risk for developing a B-cell malignancy, although it occurs only in a minority of cases. PCBL is most often a transient state, but a monoclonal population can emerge and persist. Prospective studies are needed to distinguish stable from progressive forms of B-cell lymphocytosis and to clarify the etiologic role of environmental exposures. 相似文献
974.
Y Shim T G Hampton C A Straley J K Harrison L A Spero T M Bashore A D Pasipoularides 《Circulation research》1992,71(5):1174-1184
To investigate complementarity and competitiveness between the intrinsic and extrinsic components of the total left ventricular systolic load, hemodynamic data from 18 elderly subjects with severe aortic stenosis were analyzed before and after balloon dilation of the stenosed aortic valve. Multisensor micromanometric pressure measurements allowed calculation (simplified Bernoulli equation) of the ejection velocity and aortic input impedance spectra. Despite a 32% increase in the aortic valve area (from 0.56 +/- 0.04 to 0.74 +/- 0.05 cm2 [mean +/- SEM], p < 0.01), the peak left ventricular systolic pressure fell by only 12% (from 189 +/- 10 to 167 +/- 8 mm Hg, p < 0.01). This was accompanied by an increase in the impedance at the same cardiac output. In a subset of patients (n = 9) in whom the peak aortic systolic pressure rose after valvuloplasty (from 115 +/- 10 to 128 +/- 12 mm Hg, p < 0.01), a 40% increase in the aortic valve area was accompanied by a marked increase in the aortic input impedance. In this subset, the steady component of the aortic input impedance increased by 24% (from 960 +/- 96 to 1,188 +/- 134 dyne.sec/ml, p < 0.05), and the characteristic impedance increased by 25% (from 106 +/- 13 to 132 +/- 19 dyne.sec/ml, p < 0.05). Because of an increased aortic impedance acutely following the procedure, the total left ventricular systolic load after balloon dilation of the stenotic valve was only slightly decreased despite a significant increase in aortic valve area. This represents an example of complementarity and competitiveness between the intrinsic and extrinsic components of the total systolic ventricular load. It may explain why improvement in left ventricular performance may be modest acutely following balloon aortic valvuloplasty. 相似文献
975.
Sim SS Kim YC Shim HS Choi JC Min DS Rhie DJ Yoon SH Hahn SJ Kim MS Jo YH 《Scandinavian journal of gastroenterology》2001,36(1):16-22
BACKGROUND: Smooth muscle relaxation induced by various agents that increase the cellular levels of cyclic nucleotides (cAMP and cGMP) is accompanied by a decrease in intracellular Ca2+ concentration. However, little is known about the differences between the inhibitory effects of cAMP and cGMP on the contraction of smooth muscle. OBJECTIVE: To compare the effects and underlying mechanisms of cAMP and cGMP on the inhibition of gastric smooth muscle contraction, cyclic nucleotide promoting agents, as well as cell membrane permeable cyclic nucleotides were used. METHODS: Isometric contraction was measured from circular muscle strips prepared from the fundus of cat stomach in a cylinder-shaped chamber filled with Krebs-Ringer solution (pH 7.4, temperature 36 degrees C) bubbled with 5% CO2 in O2. The level of inositol phosphates (IPs) was measured. RESULTS: Forskolin and sodium nitroprusside significantly inhibited acetylcholine (ACh)-induced gastric smooth muscle contraction and increased the cellular levels of cAMP and cGMP, respectively. Direct application of 8-Br-cAMP and 8-Br-cGMP also significantly inhibited ACh-induced contraction. Both verapamil and TMB-8 inhibited ACh-induced contraction. The combined inhibitory effect of verapamil and TMB-8 was significantly greater than the effect of either one, separately. Forskolin or sodium nitroprusside similarly augmented the effect of verapamil. However, the inhibitory effect of TMB-8 was augmented only by 8-Br-cGMP or sodium nitroprusside but not by 8-BrcAMP or forskolin. Forskolin and 8-Br-cAMP significantly inhibited the formation of inositol phosphates stimulated by ACh. CONCLUSIONS: cAMP inhibits the contraction mechanism associated with intracellular Ca2+ mobilization as well as extracellular Ca2+ influx, while cGMP inhibits contraction by inhibiting the mechanism associated with extracellular Ca2+ influx. 相似文献
976.
Noncovalent functionalization of carbon nanotubes for highly specific electronic biosensors 总被引:10,自引:0,他引:10 下载免费PDF全文
Chen RJ Bangsaruntip S Drouvalakis KA Kam NW Shim M Li Y Kim W Utz PJ Dai H 《Proceedings of the National Academy of Sciences of the United States of America》2003,100(9):4984-4989
Novel nanomaterials for bioassay applications represent a rapidly progressing field of nanotechnology and nanobiotechnology. Here, we present an exploration of single-walled carbon nanotubes as a platform for investigating surface-protein and protein-protein binding and developing highly specific electronic biomolecule detectors. Nonspecific binding on nanotubes, a phenomenon found with a wide range of proteins, is overcome by immobilization of polyethylene oxide chains. A general approach is then advanced to enable the selective recognition and binding of target proteins by conjugation of their specific receptors to polyethylene oxide-functionalized nanotubes. This scheme, combined with the sensitivity of nanotube electronic devices, enables highly specific electronic sensors for detecting clinically important biomolecules such as antibodies associated with human autoimmune diseases. 相似文献
977.
Kyumin Shim Radhika Gulhar Ishwarlal Jialal 《Journal of diabetes and its complications》2019,33(3):212-216
Introduction
Metabolic syndrome (MetS) is a disorder defined by having three of five features: increased waist circumference (WC), hypertriglyceridemia, decreased high-density lipoprotein-cholesterol, hypertension and an elevated blood glucose (BG). Metabolic Syndrome ( MetS) affects 35% of American adults and significantly increases risk for Atherosclerotic cardiovascular disease (ASCVD) and type-2 diabetes (T2DM). An understanding of the metabolome will help elucidate the pathogenesis of MetS and lead to better management. We hypothesize that the metabolites, gamma-aminobutyric acid (GABA), d-pyroglutamic acid (PGA) and N-acetyl-d-tryptophan (NAT) will be altered in nascent MetS patients without the confounding of ASCVD or T2DM. We also correlated these metabolites with biomarkers of inflammation.Patients and methods
This was an exploratory study of 30 patients with nascent MetS and 20 matched controls undertaken in 2018.Metabolites were evaluated from patient's frozen early morning urine samples and were correlated with biomarkers of inflammation and adipokines. They were assayed by the NIH Western Metabolomics Center using liquid chromatography/mass spectrometry and standardized to urinary creatinine. All patients had normal hepatic and renal function.Results
GABA and PGA levels were significantly increased in MetS patients compared to controls: 2.8-fold and 2.9-fold median increases respectively with p?<?0.0001 and p?=?0.004, possibly deriving from glutamate. NAT was significantly decreased by 90% in MetS patients compared to controls, p?<?0.001. GABA correlates significantly with cardio-metabolic (CM) features including WC, blood pressure systolic (BP-S) while NAT correlated inversely with WC, BP-S, blood glucose (BG) and triglycerides (TG). GABA correlated positively with chemerin, leptin, Fetuin A and endotoxin. NAT correlated inversely with WC, BP-S, BG, TG, high sensitivity C - reactive protein (hsCRP), toll-like receptor-4 (TLR-4), lipopolysaccharide binding protein (LBP), chemerin and retinol binding protein-4 (RBP-4).Conclusions
We make the novel observation of increased GABA and PGA with decreased NAT in patients with MetS. While GABA and PGA correlates positively with CM features and biomediators of inflammation, the metabolite NAT correlated inversely. Thus, GABA and PGA could contribute to the pro-inflammatory state of MetS while NAT could mitigate this pro-inflammatory response. 相似文献978.
Dr. J. Aisenberg MD J. Wagreich J. Shim S. Almer E. Peen T. Heimann I. M. Gelernt A. Greenstein P. Rubin N. Harpaz L. Mayer D. Sachar 《Digestive diseases and sciences》1995,40(9):1866-1872
Refractory pouchitis (RP) is a debilitating complication of ileal pouch reservoirs that affects hypothesized that it reflects underlying Crohn's disease. Since perinuclear anti-neutrophil cytoplasmic antibody (pANCA) is found in approximately 70% of ulcerative colitis patients but only rarely in Crohn's disease patients, it may help distinguish Crohn's disease from ulcerative colitis. Therefore, to test whether RP reflects missed Crohn's disease, we determined the ANCA status of 26 patients with RP. The pANCA was positive in 42% of cases [50% of Kock pouch cases and 33% of ileoanal pull-through (IAPT) cases] and 57% of matched control subjects without pouchitis (N=42,P=NS). Moreover, 3/6 (50%) of IAPT RP subjects whose signs and symptoms most suggested Crohn's disease tested positive for pANCA. When compared to controls, IAPT cases exhibited significantly more preoperative extraintestinal manifestations (EIMs) of inflammatory bowel disease (P<0.05). The presence of preoperative EIMs was 100% predictive of postoperative EIMs (P<0.05). Review of pouch biopsies from cases of RP revealed no pathognomonic histologic features of Crohn's disease. These data confirm our previous suggestion that RP does not reflect underlying Crohn's disease but may be associated with the EIMs of inflammatory bowel disease. 相似文献
979.
We describe a case in which a polytetrafluoroethylene (PTFE)-covered stent was implanted to treat impending rupture of a coronary artery pseudoaneurysm related to a chest stab wound. In this case, transthoracic echocardiography was used to verify the characteristics of the pseudoaneurysm, and we concluded that a PTFE-covered stent may prevent rupture in post-traumatic pseudoaneurysm. 相似文献
980.
Plasma fibronectin levels in ischemic heart disease 总被引:6,自引:0,他引:6
Fibronectin is a paradigm adhesive protein which has been implicated in the regulation of several cellular processes and cell-cell interactions. Large amounts of fibronectin have been detected in atherosclerotic plaques, while hypertension in animal models has been shown to rapidly increase fibronectin expression in arterial walls. The aim of the present study was to determine the levels of plasma fibronectin (FN) in 133 patients with ischemic heart disease and in 36 normal controls, and to investigate the possible association with blood pressure. Plasma FN levels in patients with ischemic heart disease were found to be significantly elevated (mean+/-S.D.; 46.5+/-14.2 mg/dl) compared with the control group (38.0+/-14.2 mg/dl) (P=0.002). Plasma FN concentrations were significantly different between the hypertensive group (52.9+/-14.5 mg/dl) and the normal blood pressure group (41.4+/-11.8 mg/dl) among the patients with ischemic heart disease (P<0.001). Plasma FN concentration was positively correlated with total cholesterol, triglyceride, systolic blood pressure and body mass index. In conclusion, the plasma fibronectin level may have pathogenetic implications in association with lipid components and blood pressure in patients with ischemic heart disease. 相似文献