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921.
922.
CONTEXT: Pituitary adenomas in Cushing disease (CD) are usually small and difficult to visualize. Bilateral inferior petrosal venous sampling (BIPSS) before and after ovine CRH stimulation is reserved for patients who have ACTH-dependent Cushing syndrome and negative magnetic resonance imaging (MRI) or positive MRI but inconsistent biochemical data. OBJECTIVE: The objective of the study was to evaluate the usefulness of BIPSS as a tool for localization of a pituitary adenoma in children with CD. DESIGN: The study was a retrospective review of the records of 141 children who were admitted for evaluation of CD from 1982 to 2004. SETTING: The study was conducted at a tertiary care center. INTERVENTIONS AND OUTCOME MEASURES: Lateralization of ACTH secretion during BIPSS was compared with MRI and surgical findings for the localization of a microadenoma. RESULTS: A total of 94 patients, 49 males and 45 females with an age range of 5.3 to 18.7 yr (13 +/- 3.2 yr), underwent BIPSS. Localization of a microadenoma by BIPSS agreed with surgical location in only 58% of the cases (95% confidence interval, 43-66). The combined use of information from the MRI and inferior petrosal venous sampling did not predict the location of the tumor more frequently than MRI alone (P > 0.1), which in this study localized a lesion in 39% of the patients (95% confidence interval, 28-50). The procedure was completed successfully in all patients, and no serious complications were recorded. CONCLUSIONS: Although BIPSS was safe and well tolerated in an experienced center, lateralization of the ACTH gradient during BIPSS was a poor predictor of the site of the adenoma in children with CD.  相似文献   
923.
The tumor microenvironment of colorectal carcinoma is a complex community of genomically altered cancer cells, nonneoplastic cells, and a diverse collection of microorganisms. Each of these components may contribute to carcinogenesis; however, the role of the microbiota is the least well understood. We have characterized the composition of the microbiota in colorectal carcinoma using whole genome sequences from nine tumor/normal pairs. Fusobacterium sequences were enriched in carcinomas, confirmed by quantitative PCR and 16S rDNA sequence analysis of 95 carcinoma/normal DNA pairs, while the Bacteroidetes and Firmicutes phyla were depleted in tumors. Fusobacteria were also visualized within colorectal tumors using FISH. These findings reveal alterations in the colorectal cancer microbiota; however, the precise role of Fusobacteria in colorectal carcinoma pathogenesis requires further investigation.  相似文献   
924.
Primary cystadenocarcinoma that arises in the broad ligament is extremely rare, especially when it is mucinous. We report the case of a 59-year-old woman with a cystic mass of the right broad ligament who underwent a complete excision of the mass (7 x 7 x 3 cm) with hysterectomy, right salpingo-oophorectomy, omentectomy, appendicectomy, and peritoneal biopsies. Pathologic examination showed a low-grade cystadenocarcinoma with a mucinous component limited to the broad ligament. Despite the chemotherapy (cisplatinum and cyclophosphamide) performed, early tumor recurrence occurred after approximately 6 months. Our observation revealed an abundant mucin production with pools of mucin similar to those of pseudomyxoma peritonei and an inflammatory infiltrate with prominent lipid phagocytosis. Immunohistochemical analysis demonstrated a strong and diffuse positivity for both cytokeratin 7 and epithelial membrane antigen. A less extensive staining with carcinoembryonic antigen and a focal unequivocal positivity with cytokeratin 20, particularly in mucin-secreting cells, were also observed. This finding could indicate a metaplastic process toward colonic phenotype similar to primary ovarian tumors.  相似文献   
925.
Activation of the spinal phospholipase A(2) (PLA(2)) -cyclooxygenase (COX) -prostaglandin signaling pathway is widely implicated in nociceptive processing. Although the role of spinal COX isoforms in pain signal transmission has been extensively characterized, our knowledge of PLA(2) enzymes in this cascade is limited. Among all PLA(2) groups, cytosolic calcium-dependent PLA(2) group IVA (cPLA(2)IVA) appears to be the predominant PLA(2) enzyme in the spinal cord. In the present study we sought to (i) characterize anatomical and cellular distribution and localization of cPLA(2)IVA in dorsal horn of rat spinal cord, (ii) verify efficacy and selectivity of intrathecal (IT) delivery of an antisense oligonucleotide (AS) targeting rat cPLA(2)IVA mRNA on spinal expression of this enzyme, and (iii) examine the effect of down-regulation of spinal cPLA(2)IVA on peripheral tissue injury-induced pain behavior. Here we demonstrate that cPLA(2)IVA is constitutively expressed in rat spinal cord, predominantly in dorsal horn neurons and oligodendrocytes but not in astrocytes or microglia. Intrathecal injection of AS significantly down-regulated both protein and gene expression of cPLA(2)IVA in rat spinal cord, while control missense oligonucleotide (MS) had no effect. Immunocytochemistry confirmed that the reduction occurred in neurons and oligodendrocytes. cPLA(2)IVA AS did not alter expression of several other PLA(2) isoforms, such as secretory PLA(2) (groups IIA and V) and calcium-independent PLA(2) (group VI), indicating that the AS was specific for cPLA(2)IVA. This selective knockdown of spinal cPLA(2)IVA did not change acute nociception (i.e. paw withdrawal thresholds to acute thermal stimuli and intradermal formalin-induced first phase flinching), however, it significantly attenuated formalin-induced hyperalgesia (i.e. second phase flinching behavior), which reflects spinal sensitization. Thus the present findings suggest that cPLA(2)IVA may specifically participate in spinal nociceptive processing.  相似文献   
926.
Infantile onset cardiomyopathies are highly heterogeneous with several phenocopies compared with adult cardiomyopathies. Multidisciplinary management is essential in determining the underlying etiology in children's cardiomyopathy. Elevated urinary excretion of 3‐methylglutaconic acid (3‐MGA) is a useful tool in identifying the etiology in some metabolic cardiomyopathy. Here, we report the delayed appearance of 3‐MGA‐uria, between 6 and 18 months in three patients (out of 100 childhood onset cardiomyopathy) with neonatal onset cardiomyopathy, secondary to TMEM70 mutations and TAZ mutations (Barth syndrome), in whom extensive metabolic investigations, performed in the first weeks of life, did not display 3‐MGA‐uria. Serial retrospective evaluations showed full characteristic features of TMEM70 and TAZ mutations (Barth syndrome) in these three patients, including a clearly abnormal monolysocardiolipin/cardiolipin ratio in the two Barth syndrome patients. Serially repeated metabolic investigations finally discovered the 3‐MGA‐uria biomarker in all three patients between the age of 6 and 18 months. Our observation provides novel insights into the temporal appearance of 3‐MGA‐uria in TMEM70 and TAZ mutations (Barth syndrome) and focus the importance of multidisciplinary management and careful evaluation of family history and red flag signs for phenocopies in infantile onset cardiomyopathies.  相似文献   
927.
Immune responses to vaccination are tested in clinical trials. This process usually requires years especially when immune memory and persistence are analyzed. Markers able to quickly predict the immune response would be very useful, particularly when dealing with emerging diseases that require a rapid response, such as avian influenza. To address this question we vaccinated healthy adults at days 1, 22, and 202 with plain or MF59-adjuvanted H5N1 subunit vaccines and tested both cell-mediated and antibody responses up to day 382. Only the MF59-H5N1 vaccine induced high titers of neutralizing antibodies, a large pool of memory H5N1-specific B lymphocytes, and H5-CD4+ T cells broadly reactive with drifted H5. The CD4+ response was dominated by IL-2+ IFN-γ IL-13 T cells. Remarkably, a 3-fold increase in the frequency of virus-specific total CD4+ T cells, measurable after 1 dose, accurately predicted the rise of neutralizing antibodies after booster immunization and their maintenance 6 months later. We suggest that CD4+ T cell priming might be used as an early predictor of the immunogenicity of prepandemic vaccines.  相似文献   
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929.
930.
Since its outbreak in December 2019, a consistent number of case reports have been published describing a complex spectrum of skin manifestations associated with COVID‐19. We report a first observation of demodicosis of the scalp after a severe acute respiratory syndrome coronavirus 2 (SARS‐COV‐2) infection.  相似文献   
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