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71.
72.
Polarized dermoscopy enables visualization of linear shiny white structures in melanomas, thought to be due to the existence of fibrosis in the dermis. Our objective was to establish the existence of two types of linear shiny white structures and assess their association with different histological structures. We performed a cross-sectional study including all non-acral, non-facial melanomas from our hospital with linear shiny white structures. The outcome variable was the type of linear shiny white structures: shiny white streaks and white strands. We evaluated their association with explanatory variables that may affect the reflectance of melanomas and Breslow index. We used χ2 statistics and also calculated the sensitivity and specificity of each linear shiny white structure to predict those variables. We detected linear shiny white structures in 118 melanomas. Regarding shiny white streaks, we only found a statistically significant positive relationship with fibrosis in the papillary dermis. Regarding white strands, we found statistically significant and positive relationships with hyperkeratosis, Breslow index of 0.8 mm or more and acanthosis. Sensitivity and specificity study revealed that the presence of shiny white streaks was the most sensitive (81.7%) and specific (72.3%) for fibrosis in the papillary dermis, and presence of white strands was the most sensitive (91.1%) and specific (85.7%) for hyperkeratosis.  相似文献   
73.
Primary cutaneous posttransplant lymphoproliferative disorders (PTLD) are rare. This retrospective, multicenter study of 35 cases aimed to better describe this entity. Cases were (re)‐classified according to the WHO‐EORTC or the WHO 2008 classifications of lymphomas. Median interval between first transplantation and diagnosis was 85 months. Fifty‐seven percent of patients had a kidney transplant. Twenty‐four cases (68.6%) were classified as primary cutaneous T cell lymphoma (CTCL) and 11 (31.4%) as primary cutaneous B cell PTLD. Mycosis fungoides (MF) was the most common (50%) CTCL subtype. Ten (90.9%) cutaneous B cell PTLD cases were classified as EBV‐associated B cell lymphoproliferations (including one plasmablastic lymphoma and one lymphomatoid granulomatosis) and one as diffuse large B cell lymphoma, other, that was EBV‐negative. Sixteen (45.7%) patients died after a median follow‐up of 19.5 months (11 [68.8%] with CTCL [6 of whom had CD30+ lymphoproliferative disorders (LPD)] and 5 [31.2%] with cutaneous B cell PTLD. Median survival times for all patients, CTCL and cutaneous B cell PTLD subgroups were 93, 93, and 112 months, respectively. Survival rates for MF were higher than those for CD30+ LPD. The spectrum of primary CTCL in organ transplant recipients (OTR) is similar to that in the general population. The prognosis of posttransplant primary cutaneous CD30+ LPD is worse than posttransplant MF and than its counterpart in the immunocompetent population. EBV‐associated cutaneous B cell LPD predominates in OTR.  相似文献   
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75.
INTRODUCTION: Hypereosinophilia can cause severe cardiac complications. The association between an acute lymphoblastic leukemia and hypereosinophilia was rare. We report a case of a 29-year-old man who presented a heart failure secondary to necrotic myocarditis related to an acute eosinophilic lymphoblastic leukaemia. EXEGESIS: The patient developed a heart failure and secondary a cardio-embolic stroke, due to a large mobile left ventricle thrombosis. His peripheral blood showed a total white count of 28,500 leucocytes/mm3 with 18,800 eosinophils/mm3. The myelogram cytology showed precursor B-cell acute lymphoblastic leukaemia with hypereosinophilia. CONCLUSION: The possibility of the rapid emergence of cardiac lesions in hypereosinophilic syndromes warrants very close physician vigilance. An Echocardiography and MRI performed at the early stage and in the follow-up allow to detect and to manage these cardiac disorders.  相似文献   
76.
During the last decade, we have witnessed an increase in the amount of data related with the presence of bacterial translocation in experimental models of cirrhosis. However, clinical studies have been limited by the lack of non-invasive methods to study this phenomenon. Over the past years, the research developed in our laboratory has been focused on the detection of bacterial DNA in serum and ascitic fluid of patients with cirrhosis and sterile ascites, the clinical and immunological implications of such finding. Initially, by means of a polymerase chain reaction (PCR)-based method and automated nucleotide sequencing, we were able to detect and identify the presence of fragments of bacterial DNA in the mentioned patients with culture-negative, non-neutrocytic ascites. Since then, we have accumulated a core of data suggesting that the presence of bacterial DNA may have an important role not only as a marker of bacterial translocation, but also as a short-term prognostic factor. Here, we discuss the past, present and future of this line of investigation.  相似文献   
77.
BACKGROUND/AIMS: Cirrhotic patients with spontaneous bacterial peritonitis show a marked activation of the cytokine cascade, and cytokines induce the synthesis of nitric oxide in vitro. Our aim was to assess whether patients with ascitic fluid infection show increased levels of nitric oxide, and whether this is related to the development of renal impairment. METHODS: Retrospective analysis of prospectively collected specimens from 168 patients with cirrhosis and presence of sterile or infected ascitic fluid. Routine biochemical data together with nitric oxide metabolites, tumour necrosis factor and interleukin-6 were measured. Univariate and multivariate analyses were performed to identify factors related to the development of renal impairment. RESULTS: Patients with infected ascites showed increased serum and ascitic-fluid levels of nitric oxide metabolites and cytokines compared with patients with sterile ascites. A significant direct correlation was observed between serum and ascitic fluid nitric oxide metabolite levels. Multivariate analysis identified ascitic-fluid nitric oxide metabolites as an independent predictor of renal impairment. CONCLUSIONS: The increased serum and ascitic fluid nitric oxide found in patients with infected ascites might induce a deterioration of the increased peripheral vasodilation found in this setting, leading to the development of renal impairment in a series of patients with spontaneous bacterial peritonitis.  相似文献   
78.
BACKGROUND: The detection of bacterial DNA in serum and ascitic fluid from patients with cirrhosis and ascites is interpreted as molecular evidence of intestinal bacterial translocation and considered sufficient to activate the cellular immune response. In vitro studies on ascitic fluid culture have shown a close relationship between the synthesis of several cytokines and nitric oxide and the presence of bacterial DNA. Since different cell types give rise to cytokines, flow cytometry becomes a powerful tool to discriminate between populations involved in a bacterial challenge. OBJECTIVE: To study the pre-activation status of macrophage/monocyte population ex vivo according to the presence of bacterial DNA. PATIENTS: Patients with cirrhosis and culture-negative, non-neutrocytic ascites, with or without the presence of bacterial DNA in blood and ascitic fluid were studied. METHODS: Flow cytometry analysis of intracellular cytokine expression in monocyte/macrophages from ascitic fluid was performed in basal conditions and after 12 h of cell stimulation adding lypopolysaccharide. RESULTS: Monocyte/macrophages from patients with bacterial DNA showed a significantly higher production of interleukin-6 and tumor necrosis factor alpha in basal conditions than that in cells from patients without the presence of bacterial DNA. The addition of lipopolysaccharide produced a non-significant increment in the expression of these cytokines in patients with the presence of bacterial DNA, while this increment became significant in the other group of patients. CONCLUSIONS: Bacterial translocation in patients with cirrhosis and ascites increases the basal intracellular cytokine expression, reducing its functional reserve capability.  相似文献   
79.
Besnier R  Francès C  Ankri A  Aiach M  Piette JC 《Lupus》2003,12(5):406-408
Sneddon syndrome (SNS) is characterized by the association of ischaemic cerebrovascular events and widespread livedo racemosa. Its pathophysiology is still controversial. The aim of this study was to evaluate the prevalence of factor V Leiden mutation in consecutive patients referred for SNS according to antiphospholipid antibodies (aPL) status. Fifty-three Caucasian patients were enrolled from 1996 to 2001. Diagnosis of SNS was based on the presence of a widespread livedo racemosa and at least one clinical neurologic ischaemic event. The following investigations were performed: detection of antithrombin III, protein C and protein S deficiency, lupus anticoagulant, anticardiolipin and anti-beta2 glycoprotein I antibodies, biologic false-positive test for syphilis, and factor V Leiden mutation by direct genomic analysis. Fisher's test and t-test were used for statistics. Detection of aPL on multiple determinations was negative in 31 patients (group 1) and positive in 22 patients (group 2). Factor V Leiden mutation was detected in six patients (11.3%), heterozygous in all. The frequency of this mutation was statistically higher in group 1 (6/31, 19.3%) than in group 2 (0/22; P = 0.035). Within aPL-negative SNS, the comparison of patients with versus without factor V Leiden mutation showed no difference for clinical data or familial history of thrombosis. A high prevalence of heterozygous factor V mutation was found in aPL-negative patients with SNS. This finding adds further arguments to consider SNS as a heterogeneous entity.  相似文献   
80.
The preferences of amino acid residues for ,psi backbone angles vary strikingly among the amino acids, as shown by the backbone angle found from the (3)J(H(alpha),H(N)) coupling constant for short peptides in water. New data for the (3)J(H(alpha),H(N)) values of blocked amino acids (dipeptides) are given here. Dipeptides exhibit the full range of coupling constants shown by longer peptides such as GGXGG and dipeptides present the simplest system for analyzing backbone preferences. The dipeptide coupling constants are surprisingly close to values computed from the coil library (conformations of residues not in helices and not in sheets). Published coupling constants for GGXGG peptides agree closely with dipeptide values for all nonpolar residues and for some polar residues but not for X = D, N, T, and Y, which are probably affected by polar side chain-backbone interactions in GGXGG peptides. Thus, intrinsic backbone preferences are already determined at the dipeptide level and remain almost unchanged in GGXGG peptides and are strikingly similar in the coil library of conformations from protein structures. The simplest explanation for the backbone preferences is that backbone conformations are strongly affected by electrostatic dipole-dipole interactions in the peptide backbone and by screening of these interactions with water, which depends on nearby side chains. Strong backbone electrostatic interactions occur in dipeptides. This is shown by calculations both of backbone electrostatic energy for different conformers of the alanine dipeptide in the gas phase and by electrostatic solvation free energies of amino acid dipeptides.  相似文献   
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