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51.
Interferon-alpha (IFN-alpha) production by human intestinal mononuclear cells. Response to virus in control subjects and in Crohn''s disease.
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The virus induced production of interferon alpha by human intestinal lamina propria mononuclear cells was investigated. Intestinal and autologous peripheral cells from control subjects and patients with Crohn's disease were cultured in vitro with and without stimulation with the Newcastle disease virus. Interferon alpha was measured and characterised in the culture supernatants after 12 hours and the kinetics of production was evaluated over the following four days of culture. No detectable interferon alpha was found in cultures of unstimulated intestinal and autologous peripheral mononuclear cells from controls and Crohn's disease whereas interferon alpha was released in all cultures stimulated with the virus. In all 12 hours experiments in both groups, virus stimulated intestinal mononuclear cells yielded significantly less interferon alpha than the autologous peripheral cells. The kinetics experiments showed that control intestinal mononuclear cells appeared to be poorly responsive to virus stimulation showing a release of interferon alpha significantly lower than that of the autologous peripheral cells. The interferon alpha release at day 4 by control cells (either intestinal or peripheral) did not differ from that measured after the first 12 hours. In contrast, the interferon alpha produced by Crohn's disease cells progressively increased during the culture period and the amount of interferon alpha measured at day 4 was significantly higher than that released at 12 hours. These data suggest that normal human intestinal mononuclear cells are down regulated in their capability of producing interferon alpha and that in Crohn's disease their activation for this function is enhanced. These data also suggest that in Crohn's disease intestinal mononuclear cells exhibit a transient hyporesponsiveness to in vitro stimulation possibly related to massive in vivo exposure to interferon alpha inducers. 相似文献
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Maria Cristina Barbaro Angelina Lettiere Ana Márcia Spanó Nakano 《Revista latino-americana de enfermagem》2014,22(1):108-114
Objective
evaluate prenatal care for adolescents in health units, in accordance with the attributes of Primary Health Care (PHC) guidelines.Method
quantitative study conducted with health professionals, using the Primary Care Assessment Tool-Brazil to assess the presence and extent of PHC attributes.Results
for all the participating units, the attribute Access scored ≤6.6; the attributes Longitudinality, Coordination (integration of care), Coordination (information systems) and Integrality scored ≥6.6, and the Essential Score ≤6.6. Comparing basic units with family health units, the attribute scores were equally distributed; Accessibility scored ≤6.6, the others attributes scored ≥6.6; however, in the basic units, the Essential Score was ≤6.6 and, in the family health units, ≥6.6.Conclusion
expanding the coverage of family health units and the training of professionals can be considered strategies to qualify health care. 相似文献54.
Stefan J. Cano Anna Mayhew Allan M. Glanzman Kristin J. Krosschell Kathryn J. Swoboda Marion Main Birgit F. Steffensen Carole Brard Franoise Girardot Christine A.M. Payan Eugenio Mercuri Elena Mazzone Bakri Elsheikh Julaine Florence Linda S. Hynan Susan T. Iannaccone Leslie L. Nelson Shree Pandya Michael Rose Charles Scott Reza Sadjadi Mackensie A. Yore Cynthia Joyce John T. Kissel 《Muscle & nerve》2014,49(3):422-430
Introduction: Trial design for SMA depends on meaningful rating scales to assess outcomes. In this study Rasch methodology was applied to 9 motor scales in spinal muscular atrophy (SMA). Methods: Data from all 3 SMA types were provided by research groups for 9 commonly used scales. Rasch methodology assessed the ordering of response option thresholds, tests of fit, spread of item locations, residual correlations, and person separation index. Results: Each scale had good reliability. However, several issues impacting scale validity were identified, including the extent that items defined clinically meaningful constructs and how well each scale measured performance across the SMA spectrum. Conclusions: The sensitivity and potential utility of each SMA scale as outcome measures for trials could be improved by establishing clear definitions of what is measured, reconsidering items that misfit and items whose response categories have reversed thresholds, and adding new items at the extremes of scale ranges. Muscle Nerve 49 :422–430, 2014 相似文献
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Ekaterina Krauss Abbas Agaimy Angelina Gottfried Juergen Maiss Thomas Weidinger Heinz Albrecht Arndt Hartmann Werner Hohenberger Markus F Neurath Hermann Kessler Jonas Mudter 《International journal of clinical and experimental pathology》2014,7(11):7419-7431
Background & aims: Ileo-colonic strictures are common complication of Crohn’s disease (CD), and may result in repeated endoscopic or surgical therapy with a risk of further complications, such as perforation or short bowel syndrome. Strictures develop as a consequence of tissue remodelling and fibrosis due to chronic inflammation. This study compares the outcome of CD patients undergoing primarily endoscopic treatment with those undergoing surgery at an university hospital. Methods: In this study we retrospectively included 88 CD patients with intestinal strictures (37 males, 51 females, mean age 40 years, range 19-65 years) of both our medical and our surgical department, who underwent either surgical or endoscopic therapy between January 2002 and January 2006 with prospective, controlled follow-up, extended till January 2010 (mean follow-up period: 5 years; range 4-8 years). The primary end-point was operation- and symptom-free time. Patients were primarily divided into four groups: only surgical therapy, only endoscopic therapy, endoscopy with subsequent surgery, and initial surgical therapy followed by endoscopic dilations. Results: 53% of all patients remained surgery-free with mean follow-up of 49 months; a single endoscopic dilation was sufficient enough in 9 patients to achieve a surgery-free time of 51 months, other patients required up to 5 dilations. The average interval between first and second dilation was 6.5 months, between second and third 10.5 months. In the group of patients with only endoscopic therapy, surgery- and symptom-free time was shorter, as compared to the group of only surgical therapy. We found that stenoses in the surgical group with an average length of 6.5 cm were as expected longer, as compared to the endoscopic group (3 cm, ranging from 2-4 cm). The surgery-free time was 49 months (42-71 months, P = 0.723) with a symptom-free time of 12 months (4.5-46 months, P = 0.921). In the group of only surgically treated patients, 68.4% of the patients had only one stenosis, 18.4% had 2-3 stenoses and 13.2% more than 3 stenoses. In all patients the surgery- and symptoms- free time was 69 months (57-83 months, P = 0.850 and 0.908). The other two groups showed similar results. We found no significant effect of characteristic of stenosis (length, inflammation, the number of stenoses), injection of prednisolone, disease activity at the time of dilation and medication at the time of dilation on the long-term outcome. Importantly, the success of symptom free time correlated with the diameter of the balloon. Conclusions: Endoscopic dilation should be considered as a first-line therapy for short, accessible, fibrotic strictures. Careful patient selection and proper diagnostic imaging pre-procedure are essential requirements for safe and successful treatment. The balloon diameter seems to correlate positively with the long term outcome of dilation. However, at ever shorter intervals between endoscopic interventions, surgery should be discussed as an option for further treatment. 相似文献
57.
Dina V. Markovskaya Svetlana V. Cherepanova Evgeny Yu. Gerasimov Angelina V. Zhurenok Aleksandra V. Selivanova Dmitry S. Selishchev Ekaterina A. Kozlova 《RSC advances》2020,10(3):1341
Photocatalysts based on zinc hydroxide and a solid solution of CdS and ZnS were prepared via the precipitation method and used for photocatalytic hydrogen production from aqueous solutions of inorganic (Na2S/Na2SO3) and organic (ethanol) sacrificial agents. The photocatalysts were tested in cyclic experiments for hydrogen evolution and studied using X-ray diffraction (XRD), UV-Vis diffuse reflectance spectroscopy, high-resolution transmission electron microscopy (HRTEM), energy-dispersive X-ray spectroscopy (EDX), and X-ray photoelectron spectroscopy (XPS) techniques. Different transformations of the β-Zn(OH)2 co-catalyst were observed in the presence of inorganic and organic sacrificial agents; namely, ZnS was formed in Na2S/Na2SO3 solution, whereas the formation of ε-Zn(OH)2 was detected in solution with ethanol. The composite Zn(OH)2/Cd1−xZnxS photocatalysts have great potential in various photocatalysis processes (e.g., hydrogen production, CO2 reduction, and the oxidation of organic contaminants) under visible light.The nature of the sacrificial agent affects the transformations of a Zn(OH)2 co-catalyst during photocatalytic hydrogen production. 相似文献
58.
Vigna GB Donegà P Zanca R Barban A Passaro A Pansini F Bonaccorsi G Mollica G Fellin R 《Metabolism: clinical and experimental》2002,51(11):1463-1470
Hormone replacement therapy (HRT) seems to have a favorable influence on the plasma lipid profile. Only a few investigations have examined the effects of HRT versus hepatic hydroxymethyl glutaryl coenzyme A (HMG-CoA) reductase inhibitors. We compared the relative effects of different hypolipidemic strategies on lipoproteins and coagulative parameters in women with recent-onset spontaneous menopause. In this 24-week, placebo-controlled trial, 60 consecutive healthy women aged >/= 45 years, with amenorrhea from 6 to 60 months (mean, 1.9 +/- 1.4 years), serum follicle stimulating hormone (FSH) greater than 40 U/L, and slight to moderate hypercholesterolemia (low-density lipoprotein-cholesterol [LDL-C] 160 to 250 mg/dL, high-density lipoprotein-cholesterol [HDL-C] < 75 mg/dL, and triglycerides < 200 mg/dL) were enrolled and randomized to dietetic advice (placebo group), simvastatin 10 mg, 0.625 mg of conjugated equine estrogen (CEE), or 50 microg estrogen transdermal patch (ETP). In the latter 2 cases, the progestative nomegestrol was added to estrogens (days 17 to 28 of the cicle). Lipoprotein parameters were evaluated after separating very-low-density lipoproteins (VLDLs) by ultracentrifugation, while fasting glucose and insulin, homocysteine, and hemocoagulative parameters were determined in plasma. Fifty-four patients completed the trial. Total cholesterol (TC) and LDL-C significantly decrased in the simvastatin (-62 mg/dL [-20%] and -72 mg/dL [-30%], respectively), CEE (-42 mg/dL [-13%] and -45 mg/dL [-18%]), and ETP (-30 mg/dL [-10%] and -26 mg/dL [-11%]) groups compared to baseline, but only simvastatin showed an effect significantly superior to diet alone. Apolipoprotein (Apo) B was decreased by simvastatin (-25%, P <.001) and by CEE (-10%, P <.05); again, simvastatin was more effective than either diet or ETP. Triglyceride concentration and VLDL-C were unmodified by treatments. HDL-C and Apo A-I significantly increased in the simvastatin group (+18% and +8%, respectively), while HDL-C was unmodified by both HRT regimens and Apo A-I was reduced by ETP treatment (-17%); lipoprotein[a] (Lp[a]) was decreased by both HRTs (-38%, P <.05, and -22%, P =.07, for CEE and ETP, respectively). Among coagulative parameters, plasminogen activator inhibitor-1 (PAI-1) was significantly reduced by CEE (-29%, P <.05) but not ETP treatment (+16%, P = not significant), while fibrinogen, antithrombin, and homocysteine were unaffected by therapy. Thus, HRT, particularly CEE, seems well tolerated and moderately effective in improving the lipid pattern and, perhaps, the coagulative/fibrinolytic balance in postmenopausal hypercholesterolemic women; it may represent a therapeutic option in slightly dyslipidemic subjects. Statins are preferred in case of more severe disease. 相似文献
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Christine Jeanblanc Angelina Daisy Goodrich Evan Colletti Saloomeh Mokhtari Christopher D. Porada Esmail D. Zanjani Graça Almeida‐Porada 《British journal of haematology》2014,166(2):268-278
The fetal sheep model has served as a biologically relevant and translational model to study in utero haematopoietic stem cell transplantation (IUHSCT), yet little is known about the ontogeny of the bone marrow (BM) niches in this model. Because the BMmicroenvironment plays a critical role in the outcome of haematopoietic engraftment, we have established the correlation between the fetal‐sheep and fetal‐human BM niche ontogeny, so that studies addressing the role of niche development at the time of IUHSCT could be accurately performed. Immunofluorescence confocal microscopic analysis of sheep fetal bone from gestational days (gd) 25–68 showed that the BM microenvironment commences development with formation of the vascular niche between 25 and 36 gd in sheep; correlating with the events at 10–11 gestational weeks (gw) in humans. Subsequently, between 45 and 51 gd in sheep (c. 14 gw in humans), the osteoblastic/endosteal niche started developing, the presence of CD34+ CD45+ cells were promptly detected, and their number increased with gestational age. IUHSCT, performed in sheep at 45 and 65 gd, showed significant haematopoietic engraftment only at the later time point, indicating that a fully functional BM microenvironment improved engraftment. These studies show that sheep niche ontogeny closely parallels human, validating this model for investigating niche influence/manipulation in IUHSCT engraftment. 相似文献