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1.
Pain control is one of the most challenging aspects in the management of chronic pancreatitis. Total pancreatectomy can successfully relieve the intractable abdominal pain in these patients but will inevitably result in insulin-dependent diabetes. Islet autotransplantation aims to preserve, as far as possible, the insulin secretory function of the islet cell mass thereby reducing (or even removing) the requirement for exogenous insulin administration after a total pancreactomy. Despite the relatively small number of centres able to perform these procedures, there are important technical variations in the details of their approaches. The aim of this review is to provide details of the current surgical practice for total pancreatectomy combined with islet autotransplantation, and outline the potential advantages and disadvantages of the variations adopted in each centre.  相似文献   
2.
The difficulty of fine localizing the polymorphisms responsible for genotype-phenotype correlations is emerging as an important constraint in the implementation and interpretation of genetic association studies, and calls for the definition of protocols for the follow-up of associated variants. One recent example is the 3435C>T polymorphism in the multidrug transporter gene ABCB1, associated with protein expression and activity, and with several clinical conditions. Available data suggest that 3435C>T may not directly cause altered transport activity, but may be associated with one or more causal variants in the poorly characterized stretch of linkage disequilibrium (LD) surrounding it. Here we describe a strategy for the follow-up of reported associations, including a Bayesian formalization of the associated interval concept previously described by Goldstein. We focus on the region of high LD around 3435C>T to compile an exhaustive list of variants by (1) using a relatively coarse set of marker typings to assess the pattern of LD, and (2) resequencing derived and ancestral chromosomes at 3435C>T through the associated interval. We identified three intronic sites that are strongly associated with the 3435C>T polymorphism. One of them is associated with multidrug resistance in patients with epilepsy (chi2 = 3.78, P = 0.052), and sits within a stretch of significant evolutionary conservation. We argue that these variants represent additional candidates for influencing multidrug resistance due to P-glycoprotein activity, with the IVS 26+80 T>C being the best candidate among the three intronic sites. Finally, we describe a set of six haplotype tagging single-nucleotide polymorphisms that represent common ABCB1 variation surrounding 3435C>T in Europeans.  相似文献   
3.
The growth response of the right ventricle was studied in rats following ligation of the left coronary artery, which produced infarcts comprising approximately 40% of the left ventricle. A month after surgery the weight of the right ventricle was increased 30%, and this hypertrophic change was characterized by a 17% wall thickening, consistent with the 13% greater diameter of myocytes. Myocardial hypertrophy was accompanied by an inadequate growth of the microvasculature that supports tissue oxygenation. This was seen by relative decreases in capillary luminal volume density (-27%) and capillary luminal surface density (-21%) and by an increase in the average maximum distance from the capillary wall to the mitochondria of myocytes (19%). In contrast, measurements of the mean myocyte volume per nucleus showed a proportional enlargement of these cells (32%), from 16,300 cu mu in control animals to 21,500 cu mu in experimental rats. Quantitative analysis of the right coronary artery revealed a 33% increase in its luminal area, commensurate with the magnitude of ventricular hypertrophy.  相似文献   
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Programmed myocyte cell death and activation of the immune system have been shown to occur in patients with congestive heart failure. Besides, unstable angina episodes are likely to be associated with immune activation. Our aim was to evaluate the role of changes in circulating levels of soluble Fas (sFas), suggestive of an enhanced inhibitory response to ongoing apoptosis, and soluble IL2 receptor (sIL2-R), indicative of T-lymphocyte activation, in chronic heart failure and unstable angina pectoris. Thirty patients affected by chronic heart failure (20 idiopathic and 10 ischemic cardiomyopathy) and 13 patients with unstable angina were evaluated. Twenty healthy individuals matched for age and gender were used as controls. A complete biochemical determination of indexes of myocardial damage including cardiac troponin I (cTnI) and creatine kinase (MB/CK) was performed. The results demonstrated that mean levels of sFas and sIL2-R were significantly increased in patients affected by chronic heart failure and unstable angina and were not associated with changes in renal function or with serum levels of cTnI. Highest values of sFas were found in NYHA class IV patients (IV NYHA class = 7.39 ± 0.52 vs. controls = 1.34 ± 0.12 ng/ml; P < 0.01) and more elevated in idiopathic than in ischemic cardiomyopathy (3.64 ± 0.40 vs. 1.82 ± 0.37 ng/ml; P < 0.01). Moreover, in chronic heart failure patients sFas and ejection fraction were negatively correlated (P = 0.01), whereas sFas and sIL2-R were positively correlated (P < 0.01). In unstable angina patients too, sFas and sIL2-R appeared to be correlated (P = 0.03); whereas sFas (angina group = 3.18 ± 0.39 vs. controls = 1.34 ± 0.12 ng/ml; P < 0.01) and sIL2-R (angina group = 0.46 ± 0.11 vs. controls = 0.00 UI/ml; P < 0.01) were higher in angina group than in controls. In most of the cases, the increase of sFas was associated with comparable changes in sIL2-R serum levels, indicating that the activation of Fas system is strictly associated with autoimmune–inflammatory reactions. This phenomenon, both in chronic heart failure and in unstable angina, occurs in the absence of biochemical evidences of myocardial damage and seems to parallel the activation of T cell. Soluble Fas could have a role in sustaining inflammatory response and in prolonging the detrimental effects correlated with it in chronic heart failure and angina pectoris.  相似文献   
6.
Monoclonal antibodies detect a new polymorphic antigenic determinant shared by HLA-A2, 3, 28, 29, 30, 31 and w33. This was demonstrated by population and family studies, including an HLA-A,B recombinant family, and by lysostrip experiments. Competition experiments, measuring the binding of 125I labelled MoAbs to B lymphoblastoid cell lines coated with anti-HLA conventional alloantisera and MoAbs showed that this new epitope is spatially distant from other known epitopes of A3 molecules and from monomorphic and polymorphic determinants of A2 molecules detected by monoclonal antibodies. On the other hand, anti-HLA-A2 polyclonal alloantisera are able to inhibit binding.  相似文献   
7.
A group of 45 children affected with Coeliac Disease (CD) was typed for HLA-A, B, C, D, and DR specificities. The most significant associations were found with two alleles of the D series, with both cellular and serological typing. It is suggested that the susceptibility to CD is determined by two different genes within the HLA region, the first in common with organ-specific autoimmune diseases and associated with DW3, the second possibly specific for CD and associated with Dw7.  相似文献   
8.
Thirty-four temporomandibular joints (TMJ) were examined in 17 normal subjects with two superconductive MR units at 1T and 1.5T. TMJ evaluation was performed with both SE sequences in occlusal position and with "fast" sequences (flash) during the gradual opening of the mouth. Therefore, both the anatomic features of the TMJs and their dynamic behavior during mouth opening were analyzed. The information acquired allowed the complete and non-invasive evaluation of TMJ function. The knowledge of the normal anatomic and functional patterns is of paramount importance for the diagnostic approach to TMJ pathologic conditions.  相似文献   
9.
The shell technique, used in the Pediatric Neurosurgical Department at the Catholic University, Rome, since the 1990s for the correction of trigonocephaly, is associated to a significant reduction in surgical time and intraoperative blood loss as compared to other procedures, while allowing an adequate remodelling of the bifrontal bone by means of multiple radial osteotomies. The technique does not necessitate the creation of a supraorbital bar, as the supraorbital ridges are modified in situ, further reducing the operative blood loss. In spite of reduced surgical time and manipulation, this procedure ensures aesthetic and functional results comparable to more extensive and complex cranial vault reshaping procedures. The main limitation of this technique is related to the surgical timing, as better results are obtained between 3 and 9 months of age, when the skull bone is still ductile to work with, thus allowing it to be remodelled by greenstick fractures. Moreover, in this age group, the cranial defects that result from the enlargement of the frontal bone flap by means of radial cuts and from the anterior displacement of its lateral portions may benefit from the more effective bone regeneration which characterizes younger children as compared to their older counterparts. A small number of cases showing either persistent hypotelorism or temporal depression have been observed in the post-operative period, although these residual deformities probably depend on a more extensive involvement of the cranial base in the synostotic process in these patients than on the procedure itself.  相似文献   
10.
COVID-19 is causing a high influx of patients suffering from serious respiratory complications leading the necessity to find effective therapies. These patients seem to present with cytokine perturbation and high levels of IL6. Tocilizumab and sarilumab could be effective in this condition.We retrospectively collected data about 112 consecutive hospitalized in a single center.Fifty (IL6 group) treated with tocilizumab (8 mg/kg intravenously [IV], 2 infusions 12 hours apart) or sarilumab 400 mg IV once and 62 treated with the standard of care but not anti-cytokine drugs (CONTROL group).To determine whether anti-IL6 drugs are effective in improving prognosis and reducing hospitalization times and mortality in COVID-19 pneumonia.To date 84% (42/50) of IL6 group patients have already been discharged and only 2/50 are still recovered and intubated in intensive care. Six/fifty patients (12%) died: 5/6 due to severe respiratory failure within a framework of severe acute respiratory distress syndrome (ARDS), 1 suffered an acute myocardial infarction, and 1 died of massive pulmonary thromboembolism. There were no adverse treatment events or infectious complications. Compared to the CONTROL group they showed a lower mortality rate (12% versus 43%), for the same number of complications and days of hospitalization.Anti-IL6 drugs seem to be effective in the treatment of medium to severe forms of COVID-19 pneumonia reducing the risk of mortality due to multi-organ failure, acting at the systemic level and reducing inflammation levels and therefore microvascular complications. However, it is essential to identify the best time for treatment, which, if delayed, is rendered useless as well as counterproductive. Further studies and ongoing clinical trials will help us to better define patients eligible as candidates for more aggressive intervention.  相似文献   
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