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991.
We report the case of a 37-years-old woman with inappropriate antidiuretic hormone syndrome due to an attack of acute porphyria. The patient was admitted to our hospital for abdominal pain, sleepiness and pink urine. Family and personal history were normal. Seven days before the admission the patient had a laparoscopy operation for endometriosis in her left ovary. The patient had had two normal pregnancies. The physical examination was normal, the skin turgor was good and no edema was present, the blood pressure was 140/90 mmHg. Her serum sodium was 114 mEq/L, serum osmolality 243 mOsm/kg, urine sodium 146 mEq/L and urine osmolality 457 mOsm/kg. Values from laboratory examination revealed a normal peripheral haematogram, a normal kidney function, normal liver, adrenal and thyroid function. The urine tested for amino-levulinic acid, coproporphyrin and uroporphyrin was strongly positive. These findings are compatible with Porphyria Variegata or Coproporphyria Hereditary. A diagnosis of Porphyria acute with SIADH was made, and water fluid restriction, i.v. hypertonic saline infusion and furosemide to correct the hyponatremia was begun. In 1966, lesions of the median eminence of the hypothalamus and both hypothalamic -hypophyseal tracts were described in a patient with Porphyria acute intermittent and SIADH. It was suggested that SIADH occurred because of damage to these areas of the brain from excessive exposure to porphyrins.  相似文献   
992.
The additional prognostic information provided by C-reactive protein (CRP) to parameters of left ventricular function in survivors of acute myocardial infarction (AMI) was investigated in 665 patients (326 with ST elevation and 339 with non-ST elevation). Cox multivariable analysis identified the following predictors of 6-month cardiac death: age (per 5 years hazard ratio [HR] 1.2, 95% confidence interval [CI] 1.1 to 1.4, p = 0.004), Killip class >I at presentation (HR 2.4, 95% CI 1.3 to 4.5, p = 0.0001), a reduced ejection fraction (per 5% HR 1.3, 95% CI 1.2 to 1.4, p = 0.0001), and greater CRP (per 5 mg/L HR 1.02, 95% CI 1.01 to 1.04, p = 0.02); the C-index of the model was 0.77 without and 0.78 with CRP. CRP is associated with mortality in addition to age and parameters of ventricular function (Killip class and ejection fraction) in survivors of AMI, although the relevance of its additive predictive role seems marginal.  相似文献   
993.
The normal counterpart of the neoplastic B cells in Burkitt lymphoma (BL) is still unclear. Based on immunoglobulin gene rearrangement studies, some authors suggest an origin from germinal center cells and others from memory B cells. However, most of these studies rely on cell lines or on a small series of cases. To help clarify the cell of origin of BL, semi-nested polymerase chain reaction (PCR) was performed to amplify the VDJ rearrangements of the immunoglobulin heavy chain (V(H)) genes, and the resultant amplificates were sequenced for comparison with known germline V(H) segments. The results of this approach revealed that all cases (15 endemic BL [eBL], 10 sporadic BL [sBL], and 6 AIDS-related BL) harbor mutated V(H) genes, with different mutation ranges among the 3 types of BL. The eBL and AIDS-related forms showed considerably higher mutation rates than the sBL form (5.1%, 5.4%, and 1.5%, respectively). The mutations in eBL and AIDS-related BL also showed signs of antigen selection, whereas no signs of antigen selection were found in sBL. Finally, after subcloning the amplificates, sequence analysis revealed no signs of ongoing mutations in any of the cases analyzed. Given that one of the main differences between eBL and AIDS-related BL on the one hand and sBL on the other hand is the association with Epstein-Barr virus (EBV), we compared EBV-positive and EBV-negative BLs independently of their geographic origin and HIV status. The differences in the number of somatic mutations and antigen selection were even more evident when this approach was used. According to our molecular results, it appears that EBV-positive and EBV-negative BL may originate from 2 distinct subsets of B cells, pointing to a particular role for the germinal-center reaction in the pathogenesis of these tumors. The different types of C-MYC translocation reported in BL may also be related to the different stages of B-cell maturation.  相似文献   
994.
We have investigated growth and vascularization of malignant glioma in mice upon conditional inhibition of fibroblast growth factor (FGF) receptor activity. C6 rat glioma cells were transfected with a dominant-negative fibroblast growth factor receptor-2 (FGFR2-DN) cDNA under the control of a tetracycline-regulated expression promoter (tet off) and implanted in the brain of immunodeficient mice. Magnetic resonance imaging analysis showed a significant decrease in tumor growth 14 days after implantation when FGFR2-DN was expressed compared to control. This size difference disappeared after 20 days. However, after 20 days, tumor and endothelial cells apoptosis were higher in the FGFR2-DN group and consequently angiogenesis was decreased whereas tumor cells were similarly associated with blood vessels at the tumor periphery. Pericyte coverage was not different between the two groups but a higher amount of pericytes not associated with vessels was found in the FGFR2-DN expressing group. This demonstrates, that conditional expression of inhibitor of FGF receptor activity in gliomas implanted in the brain of immunodeficient mice can be achieved efficiently, and that FGFs are major players in glioma development and in glioma angiogenesis.  相似文献   
995.
BACKGROUND: Estimates of the prevalence of atrial fibrillation (AF) in heart failure (HF) originate from patients enrolled in clinical trials. AIMS: To assess the prevalence and clinical correlates of AF among HF patients in everyday clinical practice from HF patients screened for the T-wave ALternans in Patients with Heart fAilure (ALPHA) study; to investigate the correlation between AF and functional status. METHODS AND RESULTS: Consecutive patients (N=3513) seen at nine Heart Failure Clinics were studied; 21.4% were in AF. AF prevalence was greater with increasing age (OR 1.04/year, p<0.001) in non-ischaemic cardiomyopathy (OR 2.34, p<0.001) and with increasing NYHA class (p<0.0001). Multiple logistic regression predictors of AF were age >70 years (OR 2.35), NYHA class II III or IV vs class I (OR 1.8, 4.4 and 3.1) and non-ischaemic cardiomyopathy (OR 3.2). A logistic model indicated that AF was associated with a 2.5 OR of being in NYHA class III-IV vs I-II while accounting for age, gender, left ventricular ejection fraction (LVEF), and aetiology of HF. CONCLUSIONS: The prevalence of AF in HF patients exceeds 20%, and increases with age and functional class. The presence of AF leads to a more severe NYHA class, indicating that AF contributes to the severity of heart failure.  相似文献   
996.
Based on clinical studies daily plasma exchange (PE) has become the first-choice therapy for thrombotic thrombocytopenic purpura (TTP) since 1991. Recent findings may explain its effectiveness, which particularly may include supply of ADAMTS-13 and removal of anti-ADAMTS-13 autoantibodies and unusually large von Willebrand factor (VWF) multimers. The most preferable PE regimens as well as replacement fluids are discussed and treatment-related adverse reactions are summarized. Proposals for a potential reduction of their frequency and for improvement of treatment efficiency are given. These suggestions are partially based on the experience of our institution in adult patients with severe ADAMTS-13 deficiency (<5% activity), and include (1) continuous calcium-gluconate infusion during PE in order to reduce citrate-related adverse reactions; (2) the evaluation of solvent/detergent-treated (S/D) plasma as replacement fluid in order to reduce adverse events due to fresh frozen plasma (FFP); (3) the evaluation of immunoadsorption in order to increase procedural efficiency in autoantibody removal; and (4) the substitution of ADAMTS-13 by means of recombinant drug instead of plasma.  相似文献   
997.
Severe deficiency of von Willebrand factor (VWF)-cleaving protease (ADAMTS-13) activity (<5% of normal) is a specific finding for acute idiopathic thrombotic thrombocytopenic purpura (TTP), a disorder that presents as thrombocytopenia, microangiopathic hemolytic anemia, and often organ dysfunction such as neurological disturbances or renal failure, and fever. Between January 2001 and July 2003, ADAMTS-13 activity was determined in plasma samples of 396 consecutive patients referred to our laboratory for diagnostic purposes. Plasma samples with ADAMTS-13 activity less than 5% were in addition tested for the presence of inhibitory antibodies. Patients were assigned to 10 predefined clinical categories according to information provided by the referring clinician: thrombotic microangiopathy (TMA) not further specified; neoplasia- or chemotherapy-associated TMA; TMA following hematopoietic stem cell transplantation; TMA with additional/alternative disorder; idiopathic TTP; hemolytic-uremic syndrome (HUS) not specified; HUS with diarrhea prodrome (D+HUS); atypical HUS; other hematological disorder; and no clinical information available. Severe ADAMTS-13 deficiency was found in 69 (17%) patients, including 42 with acquired idiopathic TTP, either at initial presentation or at relapse, 14 with confirmed or suspected hereditary TTP, 10 with TMA not further specified, two with neoplasia- or chemotherapy-associated TMA, and one in continued clinical remission 3.4 years after splenectomy for plasma-refractory TTP. Forty-three (62%) patients with ADAMTS-13 activity less than 5% displayed inhibitory antibodies. Severe ADAMTS-13 deficiency was found in 60% of patients diagnosed with acute idiopathic TTP, but in none of 130 patients diagnosed with HUS or in any of the 14 patients with hematopoietic stem cell transplantation-associated TMA. Thus, plasma ADAMTS-13 activity less than 5% does not identify all patients clinically diagnosed with TTP, and severe ADAMTS-13 deficiency is not invariably associated with clinical manifestations of microvascular platelet clumping.  相似文献   
998.
BACKGROUND: In chronic heart failure (CHF), changes in the extracellular space contribute to cardiac dysfunction. We aimed to determine whether aminoterminal-propeptide of type III procollagen (PIIINP), a marker of extracellular matrix turnover, might provide prognostic information in CHF patients. METHODS AND RESULTS: A total of 101 consecutive CHF patients (mean age 61.7 +/- 8.7 years, 88% males) were followed up between 1999 and 2001. The combined endpoint of the study was death and hospitalization for heart failure. During follow-up there were 15 deaths and 11 hospitalizations for worsening heart failure. At the survival analysis, age (P = .02), New York Heart Association class (P = .014), s-creatinine (P = .014), plasma-PIIINP (p-PIIINP) levels (P = .005), left ventricular ejection fraction (LVEF) (P = .0002), and a restrictive mitral filling pattern (P = .0003) predicted event-free survival. At the multivariate analysis, p-PIIINP levels predicted outcome independently of other clinical variables, hormones, and echocardiographic and exercise testing variables (P < .05 in all models). In patients with LVEF <31%, the presence of p-PIIINP >4.7 microg/L levels was significantly associated with a higher risk of death and hospitalization as compared with the other patients (event-free survival rate at 12 months: 45% versus 95%; at 24 months: 27% versus 88%; at 36 months: 18% versus 85%, P < .0001). CONCLUSIONS: In patients with CHF, PIIINP levels predict outcome independently of clinical status, hemodynamics and hormonal activation. PIIINP levels provide additional prognostic information to that of left ventricular function alone, suggesting that it may reflect more than cardiac extracellular matrix turnover.  相似文献   
999.
An unusual cause of acute-onset and progressively worsening visual loss is presented. A 60-year-old woman was referred for left homonymous hemianopsia to our Emergency Medicine Department because of a suspected vascular accident. Ten years earlier she had been diagnosed as having chronic lymphocytic leukemia. Brain computed tomography and magnetic resonance imaging revealed "bilateral foci of white matter abnormalities in the occipital regions, compatible with a diagnosis of progressive multifocal leukoencephalopathy". Her cerebrospinal fluid was positive for papovavirus JC. Progressive multifocal leukoencephalopathy due to papovavirus JC, a typical complication in AIDS patients, is a rare complication in patients with other immunosuppressive conditions, such as chronic lymphocytic leukemia.  相似文献   
1000.
We evaluated the use of CD34+ selected allogeneic peripheral blood as a source of hematopoietic progenitors for allogeneic transplantation in 11 patients with aplastic anemia (AA). The median age was 17 years (range, 6--9), and the median time between diagnosis and transplant 1 month (range, 1--4). Conditioning consisted of cyclophosphamide (50 mg/kg per day) on days--7 to--4 and antithymocyte globulin (30 mg/kg per day) on days--4 to--2 in nine patients. Total lymphoid irradiation was added to the preparative regimen for two. Graft-versus-host disease (GVHD) prophylaxis consisted of cyclosporine A and prednisone. Median doses of CD34+ and CD3+ cells infused were 3.91 x 10(6) and 0.3 x 10(6)/kg, respectively. The median time taken to achieve a neutrophil count >0.5 x 10(9)/l was 12 days and to recover a platelet count >20 x 10(9)/l, 13 days. Two patients developed acute GVHD grade I--II and one developed limited chronic GVHD. There were two treatment-related deaths. At a median follow-up of 44 months (range, 4--3), nine patients were alive with sustained and complete engraftment. This is a promising procedure in patients with AA, resulting in a rapid hematopoietic recovery, a low transplant-related mortality, and a low incidence of GVHD.  相似文献   
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