bluuebunny/crossref_metadata_2025_split huggingface dataset:
Monocyte Chemoattractant Protein-1 and Interleukin-8 are Increased in Bronchopulmonary Dysplasia: Relation to Isolation of Ureaplasma Urealyticum
Authors: Baier John R. , Loggins John , Kruger Thomas E. 
Published: August 2007

Background An exaggerated inflammatory response occurs in infants who subsequently develop bronchopulmonary dysplasia (BPD). Ureaplasma urealyticum (Uu) is frequently isolated from cultures of tracheal secretions obtained from very low birth weight infants and is associated with an increased risk of BPD. Methods We examined the relationships between isolation of genital mycoplasmas, tracheal aspirate (TA) interleukin-8 (IL-8), and monocyte chemoattractant protein-1 (MCP-1) concentrations and the development of BPD. Serial TAs were obtained prospectively from 35 very low birth weight infants, and IL-8 and MCP-1 concentrations were determined by enzyme-linked immunoadsorbent assay. Tracheal cultures for bacteria and genital mycoplasmas were performed on aspirates obtained during the first 2 days of life. Results Infants who developed BPD (n=18) were less mature (25.2±0.2 vs 27.8±0.5 weeks; P <0.001), of lower birth weight (746±28 vs 1052±41 g; P <0.001), and more likely to have a positive tracheal culture for Uu (39% vs 6%; P=0.026) than those who did not develop BPD (n=17). Tracheal concentrations of IL-8 and MCP-1 were significantly increased in infants who developed BPD (IL-8: P=0.0001; MCP-1: P <0.001, analysis of variance) and correlated with duration of mechanical ventilation and oxygen treatment. Uu-positive infants had an increased incidence of BPD (88% in infants with Uu vs 42% in infants without Uu; P=0.020) and had TA concentrations of IL-8 and MCP-1 that were significantly increased compared with those of Uu-negative infants. Conclusions Increased TA concentrations of IL-8 and MCP-1 during the first 2 weeks of life are associated with the development of BPD. Recovery of Uu from TAs is associated with a more robust inflammatory reaction and an increased risk of BPD.
Association of Reactive Nitrogen Species Metabolites, Myeloperoxidase, and Airway Inflammation in Lung Transplants
Authors: de Andrade João A. , Christie Jason D. , Alexander C. Bruce , Young K. Randall , McGiffin David C. , Zorn George L. , Jackson Robert M. 
Published: August 2007

Background We have previously reported that patients who had single or double lung transplants had higher concentrations than controls of nitrite and nitrate, which are metabolites of reactive nitrogen species (RNS), in bronchoalveolar lavage fluid (BALF) and serum. Methods This study investigates implications of RNS metabolites as markers of airway inflammation in a distinct group of lung transplant patients (n=40). All patients underwent spirometry, routine surveillance transbronchial lung biopsies, and bronchoalveolar lavage as required by clinical protocol. Four normal controls also had bronchoscopy for measurement of BALF nitrite (NO2−) and nitrate (NO3−). BALF NO2− and NO3−, myeloperoxidase (MPO), protein, and urea were assayed. Total nitrite (NO2− plus enzymatically reduced NO3−) and urea were measured in serum. Results BALF RNS metabolites were mainly NO3−. Forced expiratory volume in 1 s (FEV1) obtained near bronchoscopy was compared with best postoperative FEV1. Total nitrite in transplant patients’ BALF and serum were 3.8±0.2 and 49±5 μM, respectively. Total nitrite in controls’ BALF and serum were 2.2±0.7 and 19±2 μM, respectively ( P<0.05 compared with transplant values). Serum total nitrite correlated (Pearson product moment) with percentage of neutrophils in BALF ( R=0.650, P<0.0001), MPO ( R=0.431, P=0.0055), change in FEV1 from baseline (ΔFEV1) ( R=-0.348, P=0.0298), and days after transplantation ( R=0.345, P=0.0294). None of the associated variables, airway inflammation (quantified as a score, “B”), ΔFEV1, serum, or BALF total nitrite, were explained by infection. Univariate analysis of airway inflammation in patients showed that it was associated with BALF neutrophils, ΔFEV1, and serum total nitrite. Conclusions Serum nitrite appears to reflect the degree of airway inflammation in this lung-transplant study group.
Unanticipated Favorable Effects of Correcting Iron Deficiency in Chronic Hemodialysis Patients
Authors: Pollak Victor E. , Lorch Jonathan A. , Means Robert T. 
Published: August 2007

Background Correction of anemia in hemodialysis patients is seldom completely attained, and the response of parameters other than hemoglobin concentration to anemia correction has not been evaluated in detail. Methods Laboratory parameters that suggest iron deficiency occurred in 10-15% of 206 recombinant human erythropoietin (rhEPO)-treated patients. Oral iron was given for 9 months and intravenous iron thereafter on a patient-specific basis when iron deficiency was evident. Eighty-seven hemodialysis patients with data for 12 months were followed for another 12 months. A computerized information system enabled data management and analysis. Results With oral iron, serum ferritin decreased ( P<0.001), indicating further iron depletion. With intravenous iron, hemoglobin increased, evidence of iron deficiency decreased, and less rhEPO was needed. Striking macrocytosis appeared. Serum albumin and serum creatinine/kg body weight (an index of muscle mass) increased, while blood pressure decreased. Data were reanalyzed in four mean corpuscular volume (MCV) quartiles and two ferritin subsets at study onset. Iron deficient erythropoiesis (low MCV, mean corpuscular hemoglobin [MCH], and transferrin saturation) was striking in quartile 1; low ferritin was prevalent in all quartiles. With intravenous iron, hemoglobin increased only in quartile 1, the quartile with the greatest decrease (52%) in rhEPO dose. MCV increased in all quartiles ( P<0.001). Serum albumin increased in all MCV quartiles and both ferritin subsets, but significant creatinine/kg increase and blood pressure decrease occurred only in the low-ferritin subset. Conclusions Macrocytosis occurred with intravenous iron replacement. The universal MCV increase suggests unrecognized, inadequately treated, folic acid deficiency unmasked by an adequate iron supply. There was also improved well being. Effects were most clearly evident in patients with deficient iron stores.
Cortisol-Secreting Adrenal Adenomas Express 11β-Hydroxysteroid Dehydrogenase Type-2 Gene yet Possess Low 11β-HSD2 Activity
Authors: Mazzocchi Giuseppina , Aragona Francesco , Malendowicz Ludwik K. , Gottardo Lucia , Nussdorfer Gastone G. 
Published: August 2007

Background 11β-hydroxysteroid dehydrogenase Type-2 (11β-HSD2) is an unidirectional enzyme that catalyzes the conversion of glucocorticoid hormones cortisol and corticosterone (B) into their corresponding inactive forms, cortisone, and 11-dehydrocorticosterone (DH-B). We have provided evidence that 11β-HSD2 is expressed as messenger RNA (mRNA) and protein in human adrenocortical cells, where its activity is inhibited in vitro by the main glucocorticoid agonists, adrenocorticotropic hormone (ACTH) and angiotensin-II. It seemed worthwhile, therefore, to study the gene expression and activity of 11β-HSD2 in cortisol-secreting adrenocortical adenomas. Methods Three adrenal adenomas that produced Cushing syndrome were recruited. Three normal adrenal glands were obtained from patients who underwent unilateral nephrectomy with ipsilateral adrenalectomy for renal cancer. 11β-HSD2 gene expression was studied by reverse transcription-polymerase chain reaction (RT-PCR) in adenoma and normal adrenocortical tissue. Cortisol, B, cortisone, and DH-B production by adenoma and adrenal slices in vitro was assayed by quantitative high-performance liquid chromatography (HPLC), and the activity of 11β-HSD2 was evaluated by measuring the conversion of [3H]-cortisol to [3H]-cortisone. Results RT-PCR allowed the detection of the 11β-HSD2 mRNA in the three adrenal adenomas and normal adrenal cortices examined. Under basal conditions, adenoma slices secreted higher amounts of cortisol and B, but markedly lower amounts of cortisone and DH-B than adrenal slices. ACTH raised cortisol and B production from both specimens, and it lowered cortisone and DH-B yield. The level basal conversion of [3H]-cortisol to [3H]-cortisone was notably less in adenomas than in adrenals, and ACTH decreased it in both tissues. Conclusions Collectively, our findings indicate that cortisol-secreting adrenal adenomas express the 11β-HSD2 gene, but the activity of the enzyme is suppressed in adenomas when compared with the normal adrenal cortex. We advance the hypothesis that the elevated local concentration of steroid hormones that occur in adenomas down-regulates 11β-HSD2 activity, thereby contributing to their abnormal steroidogenic function.
Beneficial Intervention of Experimental Colitis by Passive Cigarette Smoking through the Modulation of Cytokines in Rats
Authors: Ko Joshua Ka-Shun , Sham Ngai-Fung , Guo Xin , Cho Chi-Hin 
Published: August 2007

Background Epidemiologic observations have indicated that cigarette smoking decreases the risk of ulcerative colitis, but the modes of action remain anonymous. The present study aimed to investigate the beneficial effects of passive cigarette smoking using an animal colitis model. We hypothesized that the underlying mechanisms may involve immunoregulation of cytokines. Methods Experimental colitis was induced in rats by enema administration of 2,4-dinitrobenzene sulfonic acid (DNBS). Passive cigarette smoking by rats was performed for 1 hour once daily, from 3 days before DNBS enema until they were sacrificed on day 8. Other groups of DNBS-treated rats received therapeutic treatment of cyclosporin A or pentoxifylline, a tumor necrosis factor (TNF)-α inhibitor. Macroscopic and histologic damage were graded, and the colonic levels of different cytokines and the levels/activities of parameters related to neutrophil activation were also measured. Results DNBS-induced colonic damage was improved in passive-cigarette-smoking rats. This was accompanied by attenuation of the elevated colonic myeloperoxidase and inducible nitric oxide synthase activities and leukotriene B4 level. Likewise, the augmentation in colonic levels of TNF-α, interleukin (IL)-1β, and IL-6 in colitis rats was also alleviated by passive cigarette smoking. In contrast, the deprivation of colonic IL-10 during colitis was preserved in cigarette-smoking rats. These effects were similarly accomplished by pentoxifylline and, to some degree, by cyclosporin A. Conclusions The results support the idea that the beneficial effects of passive cigarette smoking in experimental colitis involved immunoregulation of cytokines in colonic tissues.
Circadian Phase Resetting in Older People by Ocular Bright Light Exposure
Authors: Klerman E.B. , Duffy J.F. , Dijk D.-J. , Czeisler C.A. 
Published: August 2007

Background Aging is associated with frequent complaints about earlier bedtimes and waketimes. These changes in sleep timing are associated with an earlier timing of multiple endogenous rhythms, including core body temperature (CBT) and plasma melatonin, driven by the circadian pacemaker. One possible cause of the age-related shift of endogenous circadian rhythms and the timing of sleep relative to clock time is a change in the phase-shifting capacity of the circadian pacemaker in response to the environmental light-dark cycle, the principal synchronizer of the human circadian system. Methods We studied the response of the circadian system of 24 older men and women and 23 young men to scheduled exposure to ocular bright light stimuli. Light stimuli were 5 hours in duration, administered for 3 consecutive days at an illuminance of ˜10,000 lux. Light stimuli were scheduled 1.5 or 3.5 hours after the CBT nadir to induce shifts of endogenous circadian pacemaker to an earlier hour (phase advances) or were scheduled 1.5 hours before the CBT nadir to induce shifts to a later hour (phase delays). The rhythms of CBT and plasma melatonin assessed under constant conditions served as markers of circadian phase. Results Bright light stimuli elicited robust responses of the circadian timing system in older people; both phase advances and phase delays were induced. The magnitude of the phase delays did not differ significantly between older and younger individuals, but the phase advances were significantly attenuated in older people. Conclusions The attenuated response to light stimuli that induce phase advances does not explain the advanced phase of the circadian pacemaker in older people. The maintained responsiveness of the circadian pacemaker to light implies that scheduled bright light exposure can be used to treat circadian phase disturbances in older people.
Adenosine and Hemodialysis in Humans
Authors: Guieu Régis , Brunet Philippe , Sampol Jérome , Bechis Guy , Fenouillet E. , Mege J.L. , Capo C. , Vitte J. , Ibrahim Z. , Carrega L. , Lerda D. , Rochat Hervé , Berland Yvon , Dussol Bertrand 
Published: August 2007

Background Infections and hypotension are serious complications that develop during hemodialysis (HD) treatment. Adenosine (ADO), a strong hypotensive and immunosuppressive agent, may participate in these two HD complications, because high concentrations of ADO metabolites are found in dialyzed human plasma. ADO, which is released by endothelial cells, is quickly transformed into inosine (INO) by plasmatic ADO deaminase (ADA) and mononuclear cell ADO deaminase (MCADA). In plasma, the degradation of ADO into INO and its uptake by red blood cells (RBC) are both very rapid, resulting in the short half-life of ADO in blood. Methods Using liquid chromatography, we evaluated ADO and INO plasma concentrations before and after HD session. Results Before the HD session, ADO and INO plasma concentrations were higher in hemodialyzed patients than in controls and in peritoneally dialyzed patients. At the end of the HD session, ADO plasma concentration was increased. ADO plasma concentration for the undialyzed patients was in the same range as that of the controls. Before HD, ADA activity was higher in hemodialyzed patients (559±349 IU) than in controls (219±48 IU), and the activity rose during the session (665±135 IU). ADA activity in the undialyzed patients (222±80 IU) was in the same range as that of the controls (219±48 IU). Before the HD session, the MCADA activity (247±144 IU) was lower than in controls (624±99 IU). HD did not modify ADO RBC uptake. ADO inhibited mononuclear cell proliferation and interferon-γ production in humans. Finally, as much as 50 μM INO does not inhibit ADO uptake by RBC and does not modify ADA and MCADA activities. Conclusions These data indicate that chronic HD inhibited MCADA activity and increased ADO plasma concentration. Both high ADO plasma concentration and low MCADA activity may be involved in dialysis-induced immune system failure and thereby favor infectious diseases.
Lowering of Circulating Free-Fatty Acids Levels and Reduced Expression of Leptin in White Adipose Tissue in Postobesity Status
Authors: Greco Aldo V. , Mingrone Geltrude , Vettor Roberto , Manco Melania , Rosa Giuseppina , Capristo Esmeralda , Federspil Giovanni , Castagneto Marco , Gasbarrini Giovanni 
Published: August 2007

Background Our aim was to investigate the regulation of the gene expression of leptin in subcutaneous adipose tissue biopsies in morbid obesity before and after biliopancreatic diversion (BPD). Methods Longitudinal study in morbidly obese subjects investigated twice: before and 6 months after BPD. Fourteen morbidly obese women, 37±13 years old and with a body mass index of 51.6±8.2 kg/m2, were studied before and 6 months after BPD (40.6±8.0 kg/m2). Using reverse transcriptase polymerase chain reaction analysis, the mRNA expression of leptin was investigated in adipose tissue. Plasma leptin was measured by radioimmunoassay; plasma insulin was measured by microparticle enzyme immunoassay. Free fatty acids (FFA) were measured using a colorimetric kit. Results A significant decrease in leptin mRNA level was observed in comparison with pretreatment in BPD patients (59±34 vs 143±85 arbitrary units, P <0.01). A strict relationship between adipose tissue leptin mRNA and plasma leptin either before ( R2=0.80, P <0.0001) or after BPD ( R2=0.86, P <0.0001) and between plasma FFA concentration and insulin either before ( R2=0.65, P <0.001) or after BPD ( R2=0.92, P <0.0001) was observed. Finally, a significant correlation was found between changes in FFA and insulin ( R2=0.64, P <0.001), insulin and leptin ( R2=0.88, P <0.0001), and insulin and leptin mRNA ( R2=0.83, P <0.0001). Conclusion These data demonstrate a high correlation between leptin mRNA expression in adipose tissue and plasma leptin in postobese subjects after BPD. The significant relationship between both leptin mRNA and plasma leptin with insulin suggests that circulating insulin might regulate leptin expression. It might be hypothesized that plasma FFA concentration can act on the insulin secretion and subsequently on the leptin secretory pathway.
Saliva Analysis in the Clinical Setting: Revisiting an Underused Diagnostic Tool
Authors: Nagler Rafael M. , Hershkovich Oded , Lischinsky Sophie , Diamond Eric , Reznick Abraham Z. 
Published: August 2007

Background One purpose of this study was to compare various biochemical and immunological parameters in blood and saliva that are routinely evaluated only in the blood for general medical requirements. Another purpose was to concomitantly compare these and other oral/salivary parameters differentially in whole, parotid, and submandibular and sublingual saliva to examine the source of those parameters and their specific concentrations. Methods Twelve healthy individuals (6 women, 6 men) were examined in the blood-saliva comparison study, and 30 healthy individuals (15 women, 15 men) were studied in the intersalivary comparison study. Results On the basis of the results we obtained, we suggest a classification scheme using a whole saliva compositional profile as a diagnostic tool in the evaluation of systemic and/or local pathologies. This system may be used to analyze various components of saliva beyond those analyzed in this study, thereby increasing the clinician/s ability to locate and assess specific pathologies. We also suggest that consideration be given to the use of compositional saliva analysis in the diagnosis of general medical conditions in which there is a high correlation between the salivary and blood concentrations of relevant components. Conclusion We think that saliva analysis is a useful, worthwhile diagnostic tool because saliva collection is noninvasive, easy, and inexpensive and may be performed by the patient with no need for the involvement of medical personnel, if so desired.
In Vivo Treatment with Granulocyte Colony-Stimulating Factor does not Delay Apoptosis in Human Neutrophils by Increasing the Expression of the Vacuolar Proton ATPase
Authors: Zimbelman Julie , Thurman Gail , Leavey Patrick J. , Ellison Misoo C. , Ambruso Daniel R. 
Published: August 2007

Background Neutrophils die by apoptosis, and in vivo administration of granulocyte colony-stimulating factor (G-CSF) delays this apoptotic cell death. G-CSF administered in vitro correlates delayed apoptosis with upregulation of the vacuolar proton ATPase (v-ATPase). Because this enzyme requires assembly of membrane and cytosolic domains to function, we hypothesized that in vivo G-CSF would increase synthesis and assembly of v-ATPase components to delay apoptosis. Methods Volunteers received G-CSF for 5 days, and each had a paired control. Neutrophils were isolated from subjects before the first and after the fifth injection. Proteins from cytosol or plasma membrane or from whole cell lysates were resolved by SDS-polyacrylamide gel electrophoresis and immunoblotted with antibody to the 33kDa v-ATPase E subunit. Densitometry quantified immunoreactivity. Results No significant increase on the E subunit occurred between treated and control groups. Conclusion In vivo G-CSF does not increase the amount of v-ATPase in neutrophils. Although G-CSF in vivo delays apoptosis, the mechanism(s) by which this occurs is not known.
Effect of Desirable Fasting Triglycerides on the Postprandial Response to Dietary Fat
Authors: Miller Michael , Zhan Min , Georgopoulos Angeliki 
Published: August 2007

Background The National Cholesterol Education Program (NCEP) recently revised the “desirable” fasting triglyceride (TG) to < 150 mg/dL, and levels exceeding 200 mg/dL are defined as “high.” Methods To evaluate the postprandial response to dietary fat, 50 studies were conducted in nonobese, normocholesterolemic subjects. Following an overnight fast, subjects consumed an oral fat load (70 g/m2), and postprandial triglyceride (ppTG) measurements were assessed at 2, 4, 6, and 8 hours. Subjects were divided by fasting TG cutpoints of 100 and 150 mg/dL. Results The prevalence of ppTG samples exceeding 200 mg/dL was significantly lower with fasting TG < 100 mg/dL ( n = 116) compared with TG 100 to 150 mg/dL ( n = 56) (8% versus 25%; p = .004, chi-square analysis). In addition, fasting TG < 100 mg/dL ( n = 29) was associated with a reduced mean 4-hour peak ppTG level compared with fasting TG > 100 mg/dL ( n = 21) (125 mg/dL versus 249.8 mg/dL; p < .0001). Multiple linear regression analysis identified fasting TG as the most important determinant of the postprandial response after adjustment for other covariates ( p = .0005). Conclusions Because ppTG-rich lipoproteins contribute to coronary heart disease risk, fasting TG < 100 mg/dL may be a more desirable cutpoint than fasting TG < 150 mg/dL in coronary heart disease risk factor assessment.
Gallium-Inducible Transferrin-Independent Iron Acquisition is a Property of Many Cell Types: Possible Role of Alterations in the Plasma Membrane
Authors: Olakanmi Oyebode , Stokes John B. , Britigan Bradley E. 
Published: August 2007

BackgroundWe have previously shown that human myeloid cell types can acquire large amounts of iron (Fe)3+from low-molecular-weight chelates by a process that is independent of adenosine triphosphate and dramatically increased by gallium (Ga) and other multivalent cationic metals.MethodsTo provide further insight into the mechanism responsible and its relevance to other cellular systems, we investigated Fe acquisition from nitrilotriacetic acid (NTA) by several myeloid and nonmyeloid cell lines in the presence and absence of Ga.ResultsMost nonmyeloid cells examined exhibited similar ability to acquire Fe from NTA. Ga increased the apparent maximum velocity (Vmax), with minimal changes in apparent Michaelis constant ( Km), of all cell lines. Both erythrocytes and erythrocyte ghosts acquired Fe from NTA, which increased with Ga exposure, analogous to nucleated cells. However, liposomes made from phospholipids did not exhibit Ga-inducible Fe association. Enzymes that modify surface proteins and carbohydrates did not alter HL-60 cell Fe acquisition. Modifying HL-60 membrane fatty acid content had only a minimal effect. Ga exposure did not change membrane potential or fluidity. However, electron microscopy suggested that Ga alters plasma membrane physical properties.ConclusionMultivalent cations appear to induce changes in cell membranes that may alter their interaction with Fe3+and probably other multivalent cations.