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101.
Making a diagnosis of mitochondrial disease (MD) is extremely challenging and often employs the analysis of respiratory complex (RC) activities in biopsied skeletal muscle. Given both the invasive nature and expense of biopsied-muscle based testing for mitochondrial defects, buccal swab enzyme analysis has been explored as an alternative approach to the more invasive muscle biopsy. Case studies have recently suggested that buccal swabs from patients can be used to accurately assess mitochondrial enzyme activities including RC I and RC IV using a dipstick methodology combined with spectrophotometric analysis. In this study, forty patients with suspected MD who have previously been found to have significant defects in either RC I or RC IV in skeletal muscle were assessed by buccal swab analysis and compared to enzyme values obtained with unaffected controls (n=106) in the same age range. Buccal citrate synthase was used as an indicator of overall mitochondrial content, correlating well with overall buccal mitochondrial frataxin levels and was found to be elevated above control levels in 28% of the patients in this cohort. Of 26 cases with significant muscle RC I deficiency, 20 displayed significantly reduced levels of buccal RC I activity. All 7 of the patients with muscle RC IV deficiency showed significant buccal RC IV defect and 6 of the 7 patients with combined defects in muscle RC I and IV activity levels also exhibited analogous deficiencies in both buccal RC I and RC IV activities. In conclusion, the relatively high correlation (over 82%) of buccal and muscle RC deficiencies further supports the validity of this non-invasive approach as a potentially useful tool in the diagnosis of MD.  相似文献   
102.
Buccal bifurcation cyst (BBC) is a rare inflammatory odontogenic cyst that typically occurs at the buccal region of the first or second mandibular molars of children. In the current case, a 9-year-old boy complained of an extraoral soft tissue painful swelling. Intraoral examination revealed a partial eruption of the right permanent mandibular first molar with drainage of purulent material and clinical absence of the left mandibular first molar. Panoramic radiographic and computed tomography showed two well-defined areas surrounding the mandibular first molars consistent with cystic lesions. Surgical enucleations were performed and histopathologic analysis revealed inflammatory cysts. Based on the clinical, microscopic, radiographic, and CT images, the diagnosis of bilateral BBC was established. Patient has been under follow-up for about 1 year showing normal bone repair and eruption of the involved teeth. Although BBC is uncommon, it is important to recognize this entity.  相似文献   
103.
The purpose of this study was to retrospectively analyze the clinical presentation, treatment, and outcomes of children with Wilms tumor (WT) and intravascular extension who were treated at a single institution. A retrospective review was conducted of medical records of all children with Wilms tumor and intravascular extension treated at Virgen del Rocio Children's Hospital between 1992 and 2010. Seven patients (median age 3.4 years, range 2-8.1 years) were identified. At diagnosis, 6 of the 7 patients (85.7%) presented with tumor thrombus that reached the right atrium (RA) and 1 patient with infrahepatic inferior vena cava (IVC) thrombus. All patients received neoadjuvant chemotherapy (SIOP 2001 protocol) with vincristine, doxorubicin, and actinomycin D. Regression of the intravascular extension of the tumor was documented in all patients. Postchemotherapy level of extension was suprahepatic IVC in 1 patient, infrahepatic IVC in 2 patients, renal vein (RV) in 1 patient, and RA in 3 patients. Nephrectomy and thrombectomy were performed in all cases, requiring cardiopulmonary bypass for the 4 patients who presented with suprahepatic IVC and RA thrombus. The other 3 patients with infrahepatic IVC and RV involvement underwent cavotomy and thrombus extraction. Computed tomography, ultrasonography, and echocardiography were used for diagnosis and follow-up. All patients remain disease-free with a median follow-up of 6.3 years (range, 2-19 years). Neoadjuvant chemotherapy for WT with intravascular extension may facilitate the resection by decreasing the extent of the tumor thrombus. Cardiopulmonary bypass is indicated for suprahepatic IVC and RA involvement. Accurate diagnostic imaging is necessary.  相似文献   
104.
Little is known about the physiological roles of the M5 muscarinic receptor, the last member of the muscarinic receptor family (M1-M5) to be cloned. In the brain, the M5 receptor subtype is preferentially expressed by dopaminergic neurons of the substantia nigra and the ventral tegmental area. Dopaminergic neurons located in the ventral tegmental area are known to play important roles in mediating both the rewarding effects of opiates and other drugs of abuse and the manifestations of opiate/drug withdrawal symptoms. We therefore speculated that acetylcholine-dependent activation of M5 receptors might modulate the manifestations of opiate reward and withdrawal. This hypothesis was tested in a series of behavioral, biochemical, and neurochemical studies using M5 receptor-deficient mice (M5-/- mice) as novel experimental tools. We found that the rewarding effects of morphine, as measured in the conditioned place preference paradigm, were substantially reduced in M5-/- mice. Furthermore, both the somatic and affective components of naloxone-induced morphine withdrawal symptoms were significantly attenuated in M5-/- mice. In contrast, the analgesic efficacy of morphine and the development of tolerance to the analgesic effects of morphine remained unaltered by the lack of M5 receptors. The finding that M5 receptor activity modulates both morphine reward and withdrawal processes suggests that M5 receptors may represent a novel target for the treatment of opiate addiction.  相似文献   
105.
The iron status of African-American infants continues to be subject to debate. We characterized the iron status of 198 9-month-old inner-city infants (94% fed iron-fortified formula) using a comprehensive panel of measures and assessing lead and inflammation markers. The proportion with iron deficiency was calculated based on three approaches (> or = 2 abnormal iron measures with or without anemia for MCV model--NHANES II, ferritin model--NHANES III, or Sweden/Honduras study) and a promising new measure-body iron, calculated from ferritin and transferrin receptor (TfR). There were no sex differences for any iron measure. Hb < 110 g/l was observed in 25%; Hb < or = 105 g/l in 10.1%. Free erythrocyte protoporphyrin (FEP) values were elevated without elevated lead concentrations or an inflammatory response: mean FEP = 86.6 microg/dl red blood cells [75.5 micromol/mol heme]; 52.3% were > 80 microg/dl (1.42 micromol/l), almost half of which were accompanied by a second abnormal iron measure. The estimated prevalence of iron deficiency was 14.4, 5.3, and 2.5% for the MCV model, ferritin model, and Sweden/Honduras cutoffs, respectively, and 4.1% for body iron < 0 mg/kg. Regulation of iron storage is immature at < 1 year of age, making estimates of iron deficiency that depend on ferritin, including body iron, suspect in this age period. Thus, the "true" prevalence of iron deficiency could not be established with confidence due to major differences in the results, depending on the guidelines used. Functional indicators of poor iron status in young infants are urgently needed.  相似文献   
106.
Pregnancy has been reported in patients with hematological malignancies, such as acute leukemia, Hodgkin and malignant lymphoma and chronic myelocytic leukemia. Only 12 cases of pregnancy occurring in patients with multiple myeloma (MM) have been reported. The present report describes 6 additional cases of this rare association that received chemotherapy during pregnancy, including in the first trimester. The newborns were 3 male and 3 female with weight >2500 g and without evidence of fetal malformations. Longer follow-up (>3 years) did not give evidence of late complications in the children. Three mothers received stem cell transplantation.  相似文献   
107.
Primary lung lymphoma (PLL) and diffuse large B-cell lymphoma (DLBCL) is a rare entity and the biological features, clinical presentation, prognosis markers and treatment have not been well defined. We present 82 cases of PLL-DLBCL in a uniform population and treated with conventional chemotherapy: CHOP (cyclophosphamide, doxorubicin vincristine and prednisone). To the best of our knowledge, this is the largest series with long term follow reported. We also performed immunohistochemical studies to determine if the cell of origin [germinal center (GC) and non-GC] have a prognostic significance. All patients were at an early stage and low-clinical risk without bulk disease and normal levels of lactic dehydrogenase and beta 2 microglobulin. Complete response was achieved in 77 cases (94%), actuarial curves at 10 years showed that event-free survival (EFS) was 90% and overall survival was 92%. Fifty-nine patients were of GC phenotype and 23 of non-GC phenotype. Complete response (93% versus 91%), EFS (91% versus 80%) and overall survival (89% versus 78%) respectively, were not statistically different. Treatment was well tolerated, and second late events have not been seen. We conclude that PLL-DLBCL is an extranodal lymphoma with a good prognosis event in patients of non-GC phenotype.  相似文献   
108.

Background and Aims

A reduction in hepatic venous pressure gradient (HVPG) is the most accurate marker for assessing the severity of portal hypertension and the effectiveness of intervention treatments. This study aimed to evaluate the prognostic potential of blood-based proteomic biomarkers in predicting HVPG response amongst cirrhotic patients with portal hypertension due to Hepatitis C virus (HCV) and had achieved sustained virologic response (SVR).

Methods

The study comprised 59 patients from two cohorts. Patients underwent paired HVPG (pretreatment and after SVR), liver stiffness (LSM), and enhanced liver fibrosis scores (ELF) measurements, as well as proteomics-based profiling on serum samples using SomaScan® at baseline (BL) and after SVR (EOS). Machine learning with feature selection (Caret, Random Forest and RPART) methods were performed to determine the proteins capable of classifying HVPG responders. Model performance was evaluated using AUROC (pROC R package).

Results

Patients were stratified by a change in HVPG (EOS vs. BL) into responders (greater than 20% decline in HVPG from BL, or <10 mmHg at EOS with >10 mmHg at BL) and non-responders. LSM and ELF decreased markedly after SVR but did not correlate with HVPG response. SomaScan (SomaLogic, Inc., Boulder, CO) analysis revealed a substantial shift in the peripheral proteome composition, reflected by 82 significantly differentially abundant proteins. Twelve proteins accurately distinguished responders from non-responders, with an AUROC of .86, sensitivity of 83%, specificity of 83%, accuracy of 83%, PPV of 83%, and NPV of 83%.

Conclusions

A combined non-invasive soluble protein signature was identified, capable of accurately predicting HVPG response in HCV liver cirrhosis patients after achieving SVR.  相似文献   
109.
OBJECTIVES: The purpose of this study was to determine whether digoxin use is associated with increased flow cytometric markers of endothelial cell and platelet activation in patients with nonvalvular atrial fibrillation (AF). BACKGROUND: Increased intracellular calcium is a key event in platelet activation, and several studies have demonstrated that digitalis activates platelets in vitro. Intracellular calcium also is a key regulator of endothelial cell function, and endogenous digitalis-like substances have been shown to affect biologic processes in endothelial cells. METHODS: We studied 30 patients with nonvalvular AF. We measured the levels of (1) platelet expression of P-selectin (CD62P), (2) platelet microparticles (PMP); and (3) endothelial microparticles (EMP) identified by anti-CD31 (EMP31) and by anti-E-selectin antibodies (EMP62E). RESULTS: Patients who were taking digoxin (n = 16; mean digoxin level = 0.93 ng/dL) did not demonstrate any significant differences in clinical or echocardiographic characteristics compared with patients not taking digoxin (n = 14). Patients taking digoxin had significantly increased levels of CD62P expression in platelets and platelet-leukocyte conjugates and markedly increased markers of endothelial activation: EMP62E and EMP31. After adjusting for potential confounders (including age, congestive heart failure, coronary artery disease, ejection fraction, antiplatelet, beta-blocker, and calcium channel blocker use), the differences persisted. CONCLUSIONS: Digoxin use in patients with AF is associated with increased levels of endothelial and platelet activation. If digitalis activates endothelial cells and platelets at pharmacologic doses, use of digitalis in conditions such as AF could predispose to thrombosis and vascular events.  相似文献   
110.
Advances in recent years in the understanding of, and the genetic diagnosis of hereditary hemochromatosis (HH) have changed the approach to iron overload hereditary diseases. The ability to use a radiologic tool (MRI) that accurately provides liver iron concentration determination, and the presence of non-invasive serologic markers for fibrosis prediction (serum ferritin, platelet count, transaminases, etc), have diminished the need for liver biopsy for diagnosis and prognosis of this disease. Consequently, the role of liver biopsy in iron metabolism disorders is changing. Furthermore, the irruption of transient elastography to assess liver stiffness, and, more recently, the ability to determine liver fibrosis by means of MRI elastography will change this role even more, with a potential drastic decline in hepatic biopsies in years to come. This review will provide a brief summary of the different non-invasive methods available nowadays for diagnosis and prognosis in HH, and point out potential new techniques that could come about in the next years for fibrosis prediction, thus avoiding the need for liver biopsy in a greater number of patients. It is possible that liver biopsy will remain useful for the diagnosis of associated diseases, where other non-invasive means are not possible, or for those rare cases displaying discrepancies between radiological and biochemical markers.  相似文献   
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