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981.
982.
Iván Alvarez Anna Sureda Maria D Caballero Alvaro Urbano-Ispizua Josep M Ribera Miguel Canales Javier García-Conde Guillermo Sanz Reyes Arranz Maria T Bernal Javier de la Serna José L Díez José M Moraleda Daniel Rubió-Félix Blanca Xicoy Carmen Martínez Marivi V Mateos Jorge Sierra 《Biology of blood and marrow transplantation》2006,12(2):172-183
We report the results of reduced-intensity conditioning allogeneic stem cell transplantation (allo-RIC) in patients with advanced Hodgkin lymphoma (HL). Forty patients with relapsed or refractory HL were homogeneously treated with an RIC protocol (fludarabine 150 mg/m(2) intravenously plus melphalan 140 mg/m(2) intravenously) and cyclosporin A and methotrexate as graft-versus-host disease (GVHD) prophylaxis. Twenty-one patients (53%) had received >2 lines of chemotherapy, 23 patients (58%) had received radiotherapy, and 29 patients (73%) had experienced treatment failure with a previous autologous stem cell transplantation. Twenty patients (50%) were allografted in resistant relapse, and 38 patients received hematopoietic cells from an HLA-identical sibling. Five patients (12%) died from early transplant-related mortality (before day +100 after allo-RIC). One-year transplant-related mortality was 25%. Acute GVHD developed in 18 patients (45%). Chronic GVHD developed in 17 (45%) of the 31 evaluable patients. The response rate 3 months after the allo-RIC was 67% (21 [52%] complete remissions and 6 [15%] partial remissions). Eleven patients received donor lymphocyte infusions (DLIs) for disease relapse. The response rate after DLI was 54% (3 complete remissions and 3 partial remissions). Overall survival (OS) and progression-free survival (PFS) were 48% +/- 10% and 32% +/- 10% at 2 years, respectively. Refractoriness to chemotherapy was the only adverse prognostic factor for both OS (63% +/- 12% versus 35% +/- 13%; P = .05) and PFS (55% +/- 16% versus 10% +/- 9%; P = .006). For patients with failure of a prior autologous hematopoietic stem cell transplantation, results were especially good for those who experienced late relapses (>/=12 months: 2-year OS and PFS were 75% +/- 16% and 70% +/- 18%, respectively). These data suggest that allo-RIC is feasible in heavily pretreated HL patients and has an acceptable early transplant-related mortality. Results are better in patients allografted in sensitive disease. Both responses observed after the development of GVHD and DLI may suggest a graft-versus-HL effect. Allo-RIC has to be considered an effective therapeutic approach for patients who have had treatment failure with a previous autologous hematopoietic stem cell transplantation. 相似文献
983.
Mucosal FOXP3-expressing CD4+ CD25high regulatory T cells in Helicobacter pylori-infected patients 总被引:2,自引:0,他引:2
Lundgren A Strömberg E Sjöling A Lindholm C Enarsson K Edebo A Johnsson E Suri-Payer E Larsson P Rudin A Svennerholm AM Lundin BS 《Infection and immunity》2005,73(1):523-531
Helicobacter pylori chronically colonizes the stomach and duodenum and causes peptic ulcers or gastric adenocarcinoma in 10 to 20% of infected individuals. We hypothesize that the inability of patients to clear H. pylori infections is a consequence of active suppression of the immune response. Here we show that H. pylori-infected individuals have increased frequencies of CD4(+) CD25(high) T cells in both the stomach and duodenal mucosa compared to uninfected controls. These cells have the phenotype of regulatory T cells, as they express FOXP3, a key gene for the development and function of regulatory T cells, as well as high levels of the cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) protein. In contrast, mucosal CD4(+) CD25(low) and CD4(+) CD25(-) cells express little FOXP3 mRNA and low levels of the CTLA-4 protein. Mucosal CD4(+) CD25(high) T cells are present in individuals with asymptomatic H. pylori infections as well as in duodenal ulcer patients. The frequencies of CD4(+) CD25(high) cells are also increased in the stomachs of H. pylori-infected patients with gastric adenocarcinoma, particularly in cancer-affected tissues. These findings suggest that regulatory T cells may suppress mucosal immune responses and thereby contribute to the persistence of H. pylori infections. 相似文献
984.
The efficacy of montelukast in the treatment of cat allergen-induced asthma in children 总被引:3,自引:0,他引:3
Phipatanakul W Nowak-Wegrzyn A Eggleston PA Van Natta M Kesavan J Schuberth K Wood RA 《The Journal of allergy and clinical immunology》2002,109(5):794-799
BACKGROUND: Montelukast is a leukotriene antagonist approved for the treatment of childhood asthma in children age 2 years and older. There are limited studies on its effects on allergic asthma in children. OBJECTIVE: We sought to evaluate montelukast's effects on upper and lower airway responses to intense cat allergen exposure. METHODS: In a double-blind, placebo-controlled, cross-over trial 18 subjects aged 6 to 14 years with cat-induced asthma were randomly assigned to receive 1 week each of either montelukast or placebo, followed by a 1-hour cat challenge in an environmental exposure unit. Upper and lower respiratory tract symptoms were rated, and spirometry and acoustic rhinometry were performed. Challenges were stopped early if the subject became too uncomfortable or had a greater than 50% decrease in FEV1. RESULTS: Overall changes in FEV1 were significantly different with montelukast treatment and remained significant after adjusting for allergen level (P =.02; adjusted P =.01). Lower respiratory tract symptom scores were significantly reduced with montelukast versus placebo (P =.007) but lost significance after adjusting for allergen level (P =.16). Challenge length was significantly longer with montelukast versus placebo (P <.001) and remained significant after adjusting for allergen level (P =.019). Montelukast did not significantly affect upper respiratory responses, as measured by means of symptom scores (P =.43) and changes in acoustic rhinometry (P =.078). CONCLUSIONS: Montelukast was significantly more effective than placebo in attenuating lower respiratory responses and extending challenge length when cat-sensitive children with mild persistent asthma were exposed to high levels of cat allergen. 相似文献
985.
13-cis retinoic acid inhibits development and progression of chronic allograft nephropathy 总被引:3,自引:0,他引:3
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Adams J Kiss E Arroyo AB Bonrouhi M Sun Q Li Z Gretz N Schnitger A Zouboulis CC Wiesel M Wagner J Nelson PJ Gröne HJ 《The American journal of pathology》2005,167(1):285-298
Chronic allograft nephropathy is characterized by chronic inflammation and fibrosis. Because retinoids exhibit anti-proliferative, anti-inflammatory, and anti-fibrotic functions, the effects of low and high doses of 13-cis-retinoic acid (13cRA) were studied in a chronic Fisher344-->Lewis transplantation model. In 13cRA animals, independent of dose (2 or 20 mg/kg body weight/day) and start (0 or 14 days after transplantation) of 13cRA administration, serum creatinine was significantly lower and chronic rejection damage was dramatically reduced, including subendothelial fibrosis of preglomerular vessels and chronic tubulointerstitial damage. The number of infiltrating mononuclear cells and their proliferative activity were significantly diminished. The mRNA expression of chemokines (MCP-1/CCL2, MIP-1alpha/CCL3, IP-10/CXCL10, RANTES/CCL5) and proteins associated with fibrosis (plasminogen activator inhibitor-1, transforming growth factor-beta1, and collagens I and III) were strikingly lower in treated allografts. In vitro, activated peritoneal macrophages of 13cRA-treated rats showed a pronounced decrease in protein secretion of inflammatory cytokines (eg, tumor necrosis factor-alpha, interleukin-6). The suppression of the proinflammatory chemokine RANTES/CCL5 x 13cRA in fibroblasts could be mapped to a promoter module comprising IRF-1 and nuclear factor-kappaB binding elements, but direct binding of retinoid receptors to promoter elements could be excluded. In summary, 13cRA acted as a potent immunosuppressive and anti-fibrotic agent able to prevent and inhibit progression of chronic allograft nephropathy. 相似文献
986.
Aldea A Campistol JM Arostegui JI Rius J Maso M Vives J Yagüe J 《American journal of medical genetics. Part A》2004,(1):67-73
Familial Mediterranean fever (FMF) is an autosomal recessive disease characterized by recurring short attacks of fever and serositis. Secondary AA amyloidosis is the worst complication of the disease and often determines the prognosis. The MEFV gene, on chromosome 16p13.3, is responsible for the disease and around 30 mutations have been reported to date. Colchicine is the standard FMF treatment today, and prevents both attacks and amyloid deposition in 95% of patients. Here we describe a three-generation Spanish kindred with five family members affected by a severe periodic inflammatory disorder associated with renal AA amyloidosis and colchicine unresponsiveness. Clinical diagnosis of definite FMF disease was made based on the Tel-Hashomer criteria set. Genetic analyses revealed that all subjects were heterozygous for the new H478Y MEFV variant, segregating with the disease. In addition, mutations in the TNFRSF1A and CIAS1/PYPAF1/NALP3 genes, related to the dominantly inherited autoinflammatory periodic syndromes, were ruled out. However, the dominant inheritance of the disease, the long fever episodes with a predominant joint involvement, and the resistance to colchicine in these patients raise the question of whether the periodic syndrome seen in this kindred is a true FMF disease with unusual manifestations or rather another MEFV-associated periodic syndrome. We conclude that the new H478Y MEFV mutation is the dominant pathological variant causing the inflammatory periodic syndrome in this kindred and that full-length analyses of the MEFV gene are needed to obtain an adequate diagnosis of patients with clinical suspicion of a hereditary periodic fever syndrome, especially those from non-ancestral populations. 相似文献
987.
Anthony J McGoron Michael Capille Michael F Georgiou Pablo Sanchez Juan Solano Manuel Gonzalez-Brito John W Kuluz 《BMC medical imaging》2008,8(1):4
Background
Assessment of cerebral blood flow (CBF) by SPECT could be important in the management of patients with severe traumatic brain injury (TBI) because changes in regional CBF can affect outcome by promoting edema formation and intracranial pressure elevation (with cerebral hyperemia), or by causing secondary ischemic injury including post-traumatic stroke. The purpose of this study was to establish an improved method for evaluating regional CBF changes after TBI in piglets. 相似文献988.
Crivellato E Belloni A Nico B Nussdorfer GG Ribatti D 《The anatomical record. Part A, Discoveries in molecular, cellular, and evolutionary biology》2004,277(1):204-208
Exocytosis is considered the main route of granule discharge in chromaffin cells. We recently provided ultrastructural evidence suggesting that piecemeal degranulation (PMD) occurs in mouse adrenal chromaffin cells. In the present study, we processed rat adrenal glands for transmission electron microscopy (TEM), and examined chromaffin cells for changes characteristic of PMD. Both adrenaline (A)- and noradrenaline (NA)-storing cells express ultrastructural features suggestive of a slow and particulate mode of granule discharge. In adrenaline-containing cells, some granules present enlarged dimensions accompanied by eroded or dissolved matrices. Likewise, a number of granules in NA-releasing cells show content reduction with variably expanded granule chambers. Dilated, empty granule containers are recognizable in the cytoplasm of both cell types. Characteristically, altered granules and empty containers are seen intermingled with normal, resting granules. In addition, chromaffin granules often show irregular profiles, with budding or tail-like projections of their limiting membranes. Thirty 150-nm-diameter membrane-bound vesicles with a moderately electron-dense or -lucent internal structure are observable in the cytoplasm of both cell types. These vesicles are seen among the granules and some of them are fused with the perigranule membranes in the process of attachment to or budding from the granules. These data add further support to the concept that PMD may be an alternative secretory pathway in adrenal chromaffin cells. 相似文献
989.
Biomechanical Properties of Esophagus during Systemic Treatment with Epidermal Growth Factor in Rats
Zhao J Yang J Vinter-Jensen L Zhuang F Gregersen H 《Annals of biomedical engineering》2003,31(6):700-709
The epidermal growth factor (EGF) is a growth factor with effects on many cell types and tissue. Morphometric and passive biomechanical properties were studied in isolated segments of the esophagus in 22 EGF-treated rats and 12 control rats. The rats were divided into groups with EGF treatment for 2, 4, 7, and 14 days (n=6 for each group except n=4 for the 14 days EGF-treatment group) or saline treatment (n=3 for each group). The mechanical test was performed as a distension experiment in vitro where the whole esophagus was stretched to its in situ length and distended with pressures up to 10 cm H2O using a ramp distension protocol. The pressure and outer diameter were recorded. Circumferential stress (force per area) and strain (deformation) were computed from the diameter and pressure data using the zero-stress state as reference. The zero-stress state was obtained by cutting esophageal rings radially. This caused the rings to open up into a sector. EGF induced pronounced morphometric changes, e.g., the wall thickness, wall cross-sectional area, and inner and outer circumferential lengths significantly increased during the EGF treatment. Histological analysis showed mucosa and submucosa growth during EGF treatment. The opening angle and residual strains increased with the highest value in the 14 days EGF-treated group (P < 0.05). The change in opening angle depended largely on the change in mucosa thickness. Furthermore, the circumferential stiffness of the esophagus reached a maximum after 7 days EGF treatment (P < 0.01). © 2003 Biomedical Engineering Society.
PAC2003: 8719Rr, 8717Ee 相似文献
990.
Anna Siniscalchi Irene Badini Antonio Cintra Kjell Fuxe Clementina Bianchi Lorenzo Beani 《Neuroscience letters》1992,140(2):235-238
Spontaneous and electrically evoked endogenous acetylcholine release and [3H]-choline efflux from slices of guinea pig nucleus basalis magnocellularis (nbM) were studied. Tetrodotoxin reduced the spontaneous endogenous release by 55%, while the Ca2+-free medium reduced it by about 30%. Evoked [3H]-choline efflux was Na+ and Ca2+ dependent and frequency related. Physostigmine, 30 μM, nearly halved the stimulation-evoked efflux; atropine, 0.15 μM, not only antagonized, but even reversed this effect into facilitation. Pirenzepine, 1 μM, and AFDX 116, 1 μM, were less effective than atropine, and reversed the inhibitory effect of physostigmine only when applied together. 4-DAMP, 0.01 μM, was ineffective. These findings indicate that acetylcholine release in guinea pig nbM slices is inhibited by the cooperation of muscarinic autoreceptors, possibly belonging to the M1 and M2 subclasses. 相似文献