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31.
Crosslineage T-cell receptor delta (TCR delta) rearrangements are widely used as tumor markers for the follow up of minimal residual disease in childhood B-precursor acute lymphoblastic leukemia (ALL) by polymerase chain reaction (PCR). The major drawback of this approach is the risk of false-negative results due to clonal evolution. We investigated the stability of V delta 2D delta 3 rearrangements in a group of 56 childhood B-precursor ALL patients by PCR and Southern blot analysis. At the PCR level, V delta 2D delta 3-to-J alpha rearranged subclones (one pathway for secondary TCR delta recombination) were demonstrated in 85.2% of V delta 2D delta 3-positive patients tested, which showed that small subclones are present in the large majority of patients despite apparently monoclonal TCR delta Southern blot patterns. Sequence analysis of V delta 2D delta 3J alpha rearrangements showed a biased J alpha gene usage, with HAPO5 and J alpha F in 26 of 32 and 6 of 32 clones, respectively. Comparison of V delta 2D delta 3 rearrangement status between diagnosis and first relapse showed differences in seven of eight patients studied. In contrast, from first relapse onward, no clonal changes were observed in six patients studied. To investigate the occurrence of crosslineage TCR delta rearrangements in normal B and T cells, fluorescence-activated cell sorter-sorted peripheral blood CD19+/CD3- and CD19-/CD3+ cell populations from three healthy donors were analyzed. V delta 2D delta 3 rearrangements were detected at low frequencies in both B and T cells, which suggests that V delta 2-to-D delta 3 joining also occurs during normal B-cell differentiation. A model for crosslineage TCR delta rearrangements in B-precursor ALL is deduced that explains the observed clonal changes between diagnosis and relapse and is compatible with multistep leukemogenesis of B-precursor ALL.  相似文献   
32.
Abstract: Sub-clinical lung impairment, mostly represented by a reduced diffusion of alveolar gases, is a recognised complication of advanced primary biliary cirrhosis. The aim of the study was to evaluate the prevalence and type of pulmonary involvement in primary biliary cirrhosis and the relationship between lung function abnormalities and selected epidemiological and clinical variables. Sixty-one patients with different stages of primary biliary cirrhosis consecutively seen in our outpatient clinic were evaluated. The advancement of primary biliary cirrhosis was characterised by the histological stage, the presence of signs of portal hypertension and the Mayo Risk Score: a Cox regression model using serum bilirubin and albumin levels, prothrombin time, age and degree of oedema as selected variables. We measured static and dynamic lung volumes, by means of a spirometer, and diffusing capacity for carbon monoxide. Rheumatological disorders were evaluated by an independent rheumatologist. No patient complained of respiratory symptoms. Airway obstruction was present in one patient. In 24 patients (39%) the alveolar diffusion capacity was reduced. We did not find any significant relationship between diffusing capacity and smoking habits, advancement of liver disease and concomitant Sjogren syndrome. Reduced diffusion capacity showed a significant correlation with the presence of complete or incomplete CREST syndrome (p<0.01) and with the presence of circulating anti-centromere antibodies (p<0.05). Alveolar diffusion capacity is frequently impaired in patients with primary biliary cirrhosis, usually in the absence of clinical manifestations. These alterations mostly affect patients with concomitant CREST syndrome. Prospective studies are needed to evaluate if these abnormalities will eventually lead to clinical symptoms and if their progression could be influenced by different therapeutic regimens for primary biliary cirrhosis.  相似文献   
33.
H5N1 Virus Evolution in Europe-An Updated Overview   总被引:1,自引:0,他引:1  
Cattoli G  Fusaro A  Monne I  Capua I 《Viruses》2009,1(3):1351-1363
Since its emergence in South East Asia in 2003, Highly Pathogenic Avian Influenza (HPAI) A/H5N1 has reportedly caused outbreaks in poultry and/or wild birds in 62 countries, of which 24 were in Europe. Interestingly, out of the many genetic clades circulating in Asia, the westward spread of HPAI A/H5N1 to Central Asia, the Middle East, Europe and Africa was dominated by one single clade, namely clade 2.2. In this paper, we review and update through phylogenetic and gene migrational analysis the information concerning the evolution and the molecular epidemiology of HPAI A/H5N1 on the European continent.  相似文献   
34.
A male infant with a prenatal diagnosis (at 20 weeks' gestation) of cystic adenomatoid malformation was delivered after 38 weeks' gestation (birth weight, 3 kg) and admitted to the neonatal intensive care unit. During the first few days of life, he developed mild respiratory distress; a chest radiograph and computed tomography scan showed multiple cystic areas in the left lower lobe with hyperinflation and herniation of the upper lobe across the midline. At 3 weeks of age, a left lower lobectomy was performed for presumed cystic malformation. To our surprise the pathology reports revealed pulmonary interstitial emphysema. The postoperative chest radiograph was unchanged, and mechanical ventilation was necessary and required progressively increasing ventilatory settings to provide adequate support. High-frequency oscillatory ventilation and selective right bronchus intubation failed to improve lung function. After 3 weeks, a left thoracotomy was repeated and lung volume reduction was performed with removal of 50' of the peripheral hyperinflated parenchyma. Postoperative recovery was rapid; the child was weaned from the ventilator after 3 days and discharged after 3 weeks. Follow-up chest X-rays showed a normally expanded right lung with mediastinal structures back to midline and a small left lung. Favorable results persisted at 3 years of follow-up. This first and successful experience with lung volume reduction in a neonate suggests that infants who need removal of a large portion of lung parenchyma to achieve adequate ventilation and gas exchange, lung volume reduction surgery should be considered as an alternative to pneumonectomy.  相似文献   
35.
36.
Chest pain and other symptoms that may represent acute coronary syndromes (ACS) are common reasons for emergency department (ED) presentations, accounting for over six million visits annually in the United States [1]. Chest pain is the second most common ED presentation in the United States. Delays in diagnosis and inaccurate risk stratification of chest pain can result in serious morbidity and mortality from ACS, pulmonary embolism (PE), aortic dissection and other serious pathology. Because of the high morbidity, mortality, and liability issues associated with both recognized and unrecognized cardiovascular pathology, an aggressive approach to the evaluation of this patient group has become the standard of care. Clinical history, physical examination and electrocardiography have a limited diagnostic and prognostic role in the evaluation of possible ACS, PE, and aortic dissection, so clinicians continue to seek more accurate means of risk stratification. Recent advances in diagnostic imaging techniques particularly computed-tomography of the coronary arteries and aorta, have significantly improved our ability to diagnose life-threatening cardiovascular disease. In an era where health care utilization and cost are major considerations in how disease is managed, it is crucial to riskstratify patients quickly and efficiently. Historically, biomarkers have played a significant role in the diagnosis and risk stratification of several cardiovascular disease states including myocardial infarction, congestive heart failure, and pulmonary embolus. Multiple biomarkers have shown early promise in answering questions of risk stratification and early diagnosis of cardiovascular pathology however many do not yet have wide clinical availability. The goal of this review will be to discuss these novel biomarkers and describe their potential role in direct patient care.  相似文献   
37.
BackgroundSex-based differences in the association between C-reactive protein (CRP) and cardiovascular events in patients with coronary artery disease (CAD) are incompletely investigated. We investigated whether there are gender differences in the association between CRP and outcome in patients with CAD after percutaneous coronary intervention (PCI).MethodsThis study included 13,170 consecutive patients with CAD: 10,098 men and 3072 women. CRP was measured on admission in all patients. The primary outcome was 1-year mortality.ResultsCRP level (median [25th–75th percentiles]) was higher in women than in men (3.08 [1.30–8.37] mg/L vs 2.30 [0.92–6.47] mg/L; P < 0.001). CRP was > 3 mg/L in 4250 men (42.1%) and 1554 women (50.6%; P < 0.001). One-year mortality was 4.9% (n = 641 deaths). Deaths occurred in 318 men with CRP > 3 mg/L and 122 men with CRP ≤ 3 mg/L (mortality estimates 7.7% and 2.1%, P < 0.001) and in 154 women with CRP > 3 mg/L and 47 women with CRP ≤ 3 mg/L (mortality estimates 10.1% and 3.2%, P < 0.001). After adjustment in the Cox model, CRP was associated with increased risk of mortality in women (adjusted hazard ratio [HR] = 1.03, 95% confidence interval [CI] 1.01–1.04, P < 0.001 for each 5 mg/L increase) and in men (adjusted HR = 1.02 [1.01–1.03], P < 0.001, for each 5 mg/L increase). CRP predicted mortality with an area under the receiver-operating characteristic curve = 0.721, [0.683–0.760] in women and 0.732, [0.707–0.757] in men (P = 0.659).ConclusionsElevated CRP levels provide similar prognostic information in men and women with CAD after PCI which is independent and supplementary to that provided by conventional cardiovascular risk factors.  相似文献   
38.
There are no premonitory physical signs or biomarkers which can identify the genotypic status in Lynch syndrome II. Diagnosis is therefore dependent on the pedigree, with attention to cancer of all anatomic sites, inclusive of those cardinal features of its natural history. The tumor spectrum in Lynch syndrome II has continued to expand commensurately with increasing interest in this disorder. We report a family showing the constant cancer features of this syndrome but, in addition, occurrences of carcinoma of the bile duct, urologic system, and extremely early-onset carcinoma of the pancreas, in patients in the direct genetic lineage who were considered to be candidates for having inherited the deleterious genotype. Diagnosis of Lynch syndrome II is crucial in targeting its surveillance and management.  相似文献   
39.
Morrison  AE; Ludlam  CA; Kessler  C 《Blood》1993,81(6):1513-1520
Data have been collected from 47 centers in Europe and North America on the treatment with porcine factor VIII concentrate of 74 acute bleeding episodes in 65 patients with acquired hemophilia. The median initial anti-human factor VIII auto-antibody inhibitor level was 38 Bethesda unit (BU)/mL (range 1.2 to 1,024) whereas that against porcine was 1 BU/mL (range 0 to 15). The mean initial dose of porcine factor VIII infused was 84 IU/kg, which increased the plasma factor VIII:C activity by 0.85 IU/mL. Therapy was continued for a mean of 8.5 days during which time the average number of infusions was 11. Objective clinical responses were rated as good or excellent in 78% of recipients. Side effects were uncommon; only one patient experienced a severe anaphylactic reaction necessitating the discontinuation of porcine FVIII therapy. After therapy, no increase in the median level of anti- human FVIII or anti-porcine antibody was noted in the group as a whole, although 13 patients showed individual increases in either anti-human or anti-porcine antibody levels or both of more than 10 BU/mL. Of the 7 patients who subsequently rebled, 5 were successfully re-treated and 2 did not respond to further porcine factor VIII treatment. Porcine factor VIII is safe and clinically effective treatment for bleeding episodes associated with acquired hemophilia and should be considered as first-line therapy for patients whose acquired anti-factor VIII:C antibody cross-reacts with porcine factor VIII:C at low levels.  相似文献   
40.
ObjectiveTo screen for Escherichia coli (E. coli) resistant to tetracycline, followed by identification of tet efflux genes by polymerase chain reaction (PCR). In addition, detection of tetracycline residues in chicken livers and kidneys were conducted using high performance liquid chromatography-tandem quadrupole mass spectrometry (HPLC-MS-MS).MethodsStrains of E. coli were isolated from samples of chicken colon and screened for tetracycline resistance. Tetracycline genes conferring resistance (Tcr) were detected by polymerase chain reaction (PCR). Most of the isolates were resistant to tetracycline (97.9%).ResultsPCR analysis indicated that Tcr E. coli R-plasmids contained tet(A), tet(B) and a combination of both efflux genes. None of the isolates contained other efflux tet genes tet (C, D, E and Y). High performance liquid chromatography-tandem quadrupole mass spectrometry (HPLC-MS-MS), a sensitive technique, was used to detect residues of chlortetracycline (CTC), oxytetracycline (OTC), doxycycline (DC) in chicken livers and kidneys. The samples containing tetracycline residues were at 0.13-0.65 pg/μL levels.ConclusionsTetracycline and other antibiotics are commonly used in the poultry and meat production industry for prevention of microbial infections. Multiple antibiotic resistant bacteria in Oman have increased to alarming levels, threatening public health, domestic and may have adverse effect on environment.  相似文献   
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