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Adrenal tumors other than neuroblastoma are uncommon in children. The most frequently encountered are adrenocortical carcinoma and pheochromocytoma. This paper offers consensus recommendations for imaging of pediatric patients with a known or suspected primary adrenal malignancy other than neuroblastoma at diagnosis and during follow-up.  相似文献   
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In patients with bicuspid aortic valve (BAV), beta-blockers (BB) are assumed to slow ascending aorta (AAo) dilation by reducing wall shear stress (WSS) on the aneurysmal segment. The aim of this study was to assess differences in AAo peak velocity and WSS in BAV patients with and without BB therapy. BAV patients receiving BB (BB+, n = 30, age: 47 ± 11 years) or not on BB (BB?, n = 30, age: 46 ± 13 years) and healthy controls (n = 15, age: 43 ± 11 years) underwent 4D flow MRI for the assessment of in vivo aortic 3D blood flow. Peak systolic velocities and 3D WSS were calculated at the anterior and posterior walls of the AAo. Both patient groups had higher maximum and mean WSS relative to the control group (p = 0.001 to p = 0.04). WSS was not reduced in the BB+ group compared to BB? patients in the anterior AAo (maximum: 1.49 ± 0.47 vs. 1.38 ± 0.49 N/m2, p = 0.99, mean: 0.76 ± 0.2 vs. 0.74 ± 0.18 N/m2, p = 1.00) or posterior AAo (maximum: 1.45 ± 0.42 vs. 1.39 ± 0.58 N/m2, p = 1.00; mean: 0.65 ± 0.16 vs. 0.63 ± 0.16 N/m2, p = 1.00). AAo peak velocity was elevated in patients compared to controls (p < 0.01) but similar for BB+ and BB? groups (p = 0.42). Linear models identified significant relationships between aortic stenosis severity and increased maximum WSS (β = 0.186, p = 0.007) and between diameter at the sinus of Valsalva and reduced mean WSS (β = ?0.151, p = 0.045). Peak velocity and systolic WSS were similar for BAV patients irrespective of BB therapy. Further prospective studies are needed to investigate the impact of dosage and duration of BB therapy on aortic hemodynamics and development of aortopathy.  相似文献   
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The role played by host-pathogen interactions in regulation of expression of streptococcal virulence factors in vivo is beginning to become clear. We have reported that the expression of 2 streptococcal virulence factors, the streptococcal pyrogenic exotoxin (Spe) A and the cysteine protease SpeB, was reciprocally modulated during infection with Streptococcus pyogenes. To identify host signals mediating this reciprocal regulation, we cocultured clonal M1T1 isolates with human peripheral blood mononuclear cells (PBMCs). In accordance with our in vivo findings, when bacteria were in direct contact with human PBMCs or were separated in transwells, expression of speA was induced, whereas expression of speB was down-regulated. This phenomenon was mediated by transferrin and lactoferrin and was influenced by the iron-saturation status of these proteins. Iron chelation from media induced expression of speA, but to a much lesser degree than did that with apotransferrin and lactoferrin, suggesting additional effects of these ferrins on modulation of expression of speA and speB. Thus, ferrins may play an important role in host-pathogen interactions in skin and mucosal tissues.  相似文献   
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Under National TB/HIV framework, all TB patients are referred by Revised National Tuberculosis Programme (RNTCP) service providers to Integrated Counseling and Testing Centers (ICTCs) for voluntary counseling and testing (C&T) and ICTC “TB-suspects” are referred to RNTCP facilities for TB diagnosis and treatment. HIV–TB coinfected patients are then referred to Anti Retroviral Treatment (ART) center for initiation of ART between two weeks and two months of initiating TB treatment. During the third phase of National AIDS Control Programme (NACP-III, April 2007–April 2012), 30749/130503 (23.6%) TB/HIV cross-referrals were lost to follow up (LTFU) and there was missed opportunity for 940/1884 (49.9%) HIV–TB coinfected patients for initiation of ART during TB treatment. This motivated Delhi State AIDS Control Society (DSACS) and State TB Cell (STC) to revise existing cross-referral strategy. The new strategy was launched in May 2012, wherein HIV–TB coinfected and HIV-positive “TB-suspects” were referred to nearest ART center for HIV care and investigations of TB at Chest Clinic/Designated Microscopy Centre (DMC) located within the same hospital instead of referral to area RNTCP facility. Outcome of the strategy was evaluated in March 2013. The new HIV–TB cross-referral strategy in Delhi has shown advantage over national strategy: first, improved retention of coinfected clients in HIV care; second, ensured timely initiation of TB-treatment and ART; and third, significantly improved survival of HIV–TB coinfected patients.  相似文献   
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Genetic polymorphisms in the methylene tetrahydrofolate reductase (MTHFR) gene have been associated with the development of acute leukemias and various malignancies. The role of MTHFR polymorphism in the development of pediatric acute lymphoblastic leukemia (ALL) has been extensively studied among north Indians in various settings, yet its association with acute leukemias remains unresolved. To evaluate the relationship between functional MTHFR polymorphisms, C677T and A1298C and possible effect on risk of ALL in adults and children in North Indian population by comparing them with healthy controls. DNA was isolated from peripheral blood of 184 ALL patients (33 adults, 151 children) and 155 controls and analyzed by a PCR-restriction fragment length polymorphism assay. The frequency of MTHFR 677CT and 1298 AC genotypes were significantly lower among adult ALL cases when compared to the controls. We found a 1.74-fold reduced risk of ALL in individuals with 1298AC polymorphic variant and a 9.17-fold decreased risk of adult ALL. However, no statistically significant difference was evident between the above polymorphisms and susceptibility to ALL in children. Polymorphisms in the MTHFR gene possibly modulate risk of ALL in north Indian adults but not in children, although larger studies are needed.  相似文献   
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Metastatic tumors to the heart usually involve right sided chambers. We report a rare case of malignant phyllodes tumor of breast with metastatic involvement of left atrium occurring through direct invasion from mediastinal micro-metastasis and presenting as a left atrial mass causing arrhythmia.  相似文献   
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