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71.
The present study was designed to establish the incidence of cytogenetic evolution (CE), defined as the acquisition of chromosomal defects during the course of MDS, in order to correlate it with the WHO classification and IPSS score, and to assess its impact on overall survival (OS) and risk of MDS/AML evolution (progression-free interval, PFI) by means of Cox models for time-dependent covariates. Adjustments for known risk factors were achieved by performing a bivariable analysis. The study was carried out in 153 MDS patients who were followed for a median period of 45.2 months. Disease progression occurred in 42.4% of patients after a 65.2-month median PFI, while CE occurred in 30.7% of patients. Our study shows that (1) CE was more common in advanced than in early MDS, and advanced MDS presented secondary chromosomal defects distinct from those of early MDS; (2) CE significantly affected OS and PFI independently of other prognostic variables; (3) del(7)(q31q34) was the only secondary chromosomal defect which significantly affected PFI; trisomy 8 had only a moderate influence.  相似文献   
72.

Purpose  

To apply the Brandwein-Gensler et al.’s histopathologic risk score (RS) system and to evaluate its impact on locoregional recurrence and overall survival in a series of cases of oral tongue cancer, along with variables of patient age and margin status.  相似文献   
73.
As part of our studies focused on the design and synthesis of new antimicrobial agents a series of 7‐fluoro‐3,4‐dihydro‐2H‐1,4‐benzothiazine derivatives ( 4a–4f , 4h ) and 7‐fluoro‐2H‐1,4‐benzothiazin‐3(4H)‐one analogues ( 4j–4o ) were synthesized and evaluated for their in vitro inhibitory activity against a representative panel of Gram‐positive and Gram‐negative bacteria strains and also toward selected fungi species. These compounds were prepared in one step from chloro‐substituted‐2‐amino‐5‐fluorobenzenethiol 6a–6c . The biological screening identified in compounds 4a , 4j and 4l the most promising results of both series showing an interesting antimicrobial activity. Our antibiotic investigation was also completed by testing the key intermediates 6a–6c . Surprisingly, 6a–6c emerged as the compounds exhibiting the highest antimicrobial activity by possessing a remarkable antibacterial effect against the Gram‐positive strains with MIC (minimal inhibitory concentration) values between 2 and 8 µg/mL and the fungi panel with MIC values between 2 and 8 µg/mL. These results may prove useful in the design of a novel pool of antimicrobial agents.  相似文献   
74.
Histamine may contribute to the pathology of MS and its animal model EAE. We explored the effects of histamine and specific HR agonists on activation and migratory capacity of myelin-autoreactive T cells. We show that histamine in vitro inhibits proliferation and IFN-γ production of mouse T cells activated against PLP(139-151). These effects were mimicked by the H1R agonist HTMT and the H2R agonist dimaprit and were associated with reduced activation of ERK½ kinase and with increased levels of cell cycle inhibitor p27Kip-1, both involved in T cell proliferation and anergy. H1R and H2R agonists reduced spontaneous and chemokine-induced adhesion of autoreactive T cells to ICAM-1 in vitro and blocked firm adhesion of these cells in inflamed brain microcirculation in vivo. Thus histamine, through H1R and H2R, inhibits activation of myelin-autoreactive T cells and their ability to traffic through the inflamed BBB. Strategies aimed at interfering with the histamine axis might have relevance in the therapy of autoimmune disease of the CNS.  相似文献   
75.
RATIONALE: Ca(2+) signaling controls the production of T helper (Th) type 2 cytokines known to be deleterious in asthma. Recently, we showed that Ca(2+) signaling was dihydropyridine (DHP)-sensitive in Th2 lymphocytes and that the DHP derivate, nicardipine, used in the treatment of cardiovascular pathologies, prevents Th2-dependent B cell polyclonal activation. OBJECTIVES: We tested the effect of nicardipine in experimental allergic asthma. METHODS: BALB/c mice immunized with ovalbumin (OVA) in alum and challenged with intranasal OVA were treated with nicardipine once the Th2 response, or even airway inflammation, was induced. We also tested the effect of nicardipine in asthma induced by transferring OVA-specific Th2 cells in BALB/c mice exposed to intranasal OVA. We checked the impact of nicardipine on T-cell responses and airway inflammation. MEASUREMENTS AND MAIN RESULTS: Nicardipine inhibited in vitro Ca(2+) response in Th2 cells. In vivo, it impeded the development of Th2-mediated airway inflammation and reduced the capacity of lymphocytes from lung-draining lymph nodes to secrete Th2, but not Th1, cytokines. Nicardipine did not affect antigen presentation to CD4(+) T lymphocytes, nor the initial localization of Th2 cells into the lungs of mice exposed to intranasal OVA; however, it reduced the production of type 2 cytokines and the amplification of the Th2 response in mice with asthma. Conversely, nicardipine had no effect on Th1-mediated airway inflammation. CONCLUSIONS: Nicardipine improves experimental asthma by impairing Th2-dependent inflammation. This study could provide a rationale for developing drugs selectively targeting DHP receptors of Th2 lymphocytes, potentially beneficial in the treatment of asthma.  相似文献   
76.
The term 'overlap syndromes of liver diseases' includes coexistence of autoimmune hepatitis (AIH), primary sclerosing cholangitis (PSC), primary biliary cirrhosis (PBC). Due to their unknown etiology, as well as their variable presentation with mixed clinical and biochemical features, these overlap syndromes are often a diagnostic and therapeutic challenge for hepatologists. The most frequent association reported occurs between AIH and PBC. More rare is the overlap between AIH and PSC, typical in young age and often concomitant with an inflammatory bowel disease as ulcerative colitis. The treatment of choice is based on ursodeoxycholic acid and immunosoppressive drugs, used at the same time or consecutively, according to the course of disease. Histological examination seems an important tool, but often does not help for a correct diagnosis due to lack of specificity. Two particular forms of variant syndrome are the so called outlier syndromes, without clear characteristics of overlap: the autoimmune cholangitis, probably a form of PBC anti-mitochondrial antibodies negative, and the hepatitis C virus related with stigmata of autoimmunity, such as nonspecific autoantibodies at low titer. The diagnostic score system elaborated in 1999 by the International AIH Group can help for diagnosis, even if its definite validity is lacking.  相似文献   
77.
78.
Agenesis of the gallbladder is a rare anomaly that is usually asymptomatic, but sometimes the patients may have symptoms compatible with a biliary disorder like cholelithiasis. Its preoperative diagnosis is often difficult, especially if dysplastic cyst is associated and simulates the gallbladder. When the diagnosis is doubtful its confirmation and treatment of dysplastic cyst require open surgery, careful dissection of the common bile duct to avoid biliary lesions and intraoperative ultrasonography or cholangiography to be performed to exclude other associated anomalies. The Authors describe the case of agenesis of gallbladder and dysplastic cyst associated and comment on its clinical, diagnostic, and therapeutic aspects.  相似文献   
79.
BACKGROUND: Hypertension has been traditionally considered a risk factor for restenosis following carotid arteriotomy. Genetic and morphological response to carotid arteriotomy in normotensive Wystar-Kyoto (WKY), spontaneously hypertensive (SHR), and Milan hypertensive (MHS) rats were analyzed. MATERIAL AND METHODS: C-myc, angiotensin II receptor-1 (AT1), angiotensin II receptor-2 (AT2), endothelin-1 receptor A (ET(A)), endothelin-1 receptor B (ET(B)), Bcl-2 family-members (Bcl-2/Bax, Bcl-X(L/S)) were analyzed in surgically injured as well as uninjured carotids of WKY and hypertensive strains (HS). Thirty-day histology and morphometry were accomplished on injured and uninjured carotids. RESULTS: C-myc mRNA is activated earlier and/or to a greater extent in hypertensive strains than in WKY. AT1 mRNA increases in WKY after injury, while it decreases in SHR and MHS. AT2 shows the opposite, decreasing in WKY and increasing in hypertensive strains. ET(A) mRNA decreases in all strains although with different timing and levels, associated with a replacement by ET(B) mRNA. Bcl-2/Bax ratio gradually decreases in WKY, while it shows only a transient decrease in SHR and MHS 4 h after the injury. Negative remodeling is observed in all injured carotids, although neointima was detected in WKY only. Thirty days following arteriotomy, morphometry demonstrated a significant decrease of luminal area, with consistent gain in the medial area in WKY, whereas hypertensive strains showed significant increase of the luminal area, consistent with a contemporary decrease of the medial area. CONCLUSIONS: Vaso-relaxant AT2 and ET(B) induced limited vasoconstriction in HS. Less apoptosis in hypertensive rats reduced cell proliferation, contrasting c-myc. These responses favorably modulated media/lumen area ratio following arteriotomy in HS.  相似文献   
80.
Archaeological, anthropological and pathological data suggest that thirteen skeletons found in a house at the Pompeii archaeological site, dated to 79 A.D., belong to one family. To verify this and to identify the relationships between these individuals, we analyzed DNA extracted from bone specimens. Specifically, hypervariable segment 1 (HVS1) of the human mitochondrial DNA (mtDNA) control region was amplified in two overlapping polymerase chain reactions and the sequences were compared to the revised Cambridge Reference Sequence. As independent controls, other polymorphic sites in HVS1, HVS2 and in the coding region were analyzed. We also amplified some short tandem repeats of the thirteen specimens. This study revealed that six of the thirteen individuals are indeed closely related.  相似文献   
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