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61.
High‐risk neuroblastoma has a poor prognosis despite multimodal treatment including high‐dose chemotherapy. A 7‐year‐old male with neuroblastoma received ex vivo‐expanded donor CD4+ T lymphocyte infusion (CD4+ DLI) after recurrence in the bone marrow following allogeneic hematopoietic stem cell transplantation from his HLA‐identical mother. The disease transiently responded to CD4+ DLI with reduction of tumor cells and a decrease of serum neuron‐specific enolase. The response was associated with development of continued high fever and an increase of cytotoxic T lymphocytes in peripheral blood. This case suggests a possibility of a graft‐versus‐tumor effect against neuroblastoma. Pediatr Blood Cancer 2009;52:895–897. © 2009 Wiley‐Liss, Inc.  相似文献   
62.
There have been few reports describing substances related to oxidative and intermediary metabolism in the cerebrospinal fluid (CSF) in patients with spinal degenerative disorders. This study investigated whether the concentrations of metabolites in the CSF differed between patients with spinal degenerative disorders and controls, and whether the concentrations of these metabolites correlated with the severity of symptoms. CSF samples were obtained from 30 patients with cervical myelopathy (Group M), 30 patients with lumbar radiculopathy (Group R), and 10 volunteers (control). Metabolites in these CSF samples were measured by nuclear magnetic resonance spectroscopy. There were no differences in the concentrations of lactate, alanine, acetate, glutamate, pyruvate, or citrate between Groups M and R, between Group M and the control, or between Group R and the control. In Group M, neither symptom duration nor the Japanese Orthopaedic Association score correlated with the concentration of any metabolite. In Group R, the symptom duration positively correlated with the concentration of lactate, glutamate, and citrate in CSF. The duration of nerve root block showed a negative correlation with the concentrations of acetate in CSF of the patients in Group R. In patients with lumbar radiculopathy, there is a possibility of increased aerobic metabolic activity or decreased gluconeogenic activity in patients with shorter symptom duration, and increased aerobic metabolic activity in patients with severe inflammation around a nerve root.  相似文献   
63.
64.
The cause(s) of sarcoidosis is unknown. Mycobacterium spp. are suspected in Europe and Propionibacterium spp. are suspected in Japan. The present international collaboration evaluated the possible etiological links between sarcoidosis and the suspected bacterial species. Formalin-fixed and paraffin-embedded sections of biopsy samples of lymph nodes, one from each of 108 patients with sarcoidosis and 65 patients with tuberculosis, together with 86 control samples, were collected from two institutes in Japan and three institutes in Italy, Germany, and England. Genomes of Propionibacterium acnes, Propionibacterium granulosum, Mycobacterium tuberculosis, Mycobacterium avium subsp. paratuberculosis, and Escherichia coli (as the control) were counted by quantitative real-time PCR. Either P. acnes or P. granulosum was found in all but two of the sarcoid samples. M. avium subsp. paratuberculosis was found in no sarcoid sample. M. tuberculosis was found in 0 to 9% of the sarcoid samples but in 65 to 100% of the tuberculosis samples. In sarcoid lymph nodes, the total numbers of genomes of P. acnes or P. granulosum were far more than those of M. tuberculosis. P. acnes or P. granulosum was found in 0 to 60% of the tuberculosis and control samples, but the total numbers of genomes of P. acnes or P. granulosum in such samples were less than those in sarcoid samples. Propionibacterium spp. are more likely than Mycobacteria spp. to be involved in the etiology of sarcoidosis, not only in Japanese but also in European patients with sarcoidosis.  相似文献   
65.
Autosomal recessive form of hyper-IgM syndrome type 2 (AR-HIGM2) is secondary to mutations affecting both alleles of AICDA gene encoding activation-induced cytidine deaminase, characterized by defects of immunoglobulin class switch recombination (CSR) and somatic hypermutation (SHM) in most of the patients. We herein report the immunological phenotype of seven patients carrying a single heterozygous R190X mutation in AICDA. Variable defect in in vivo CSR inherited as an autosomal dominant (AD) trait strongly suggests that this heterozygous AICDA mutation causes HIGM (AD-HIGM2). In AD-HIGM2 B cells, CSR was consistently found impaired in vitro. However, in contrast to AR-HIGM2, the CSR-induced double-stranded DNA breaks in the switch region of IgM heavy chain gene were detected. The SHM frequency in V regions of IgM heavy chain gene in B cells was normal in all (but one patient). The characteristics of the AD-HIGM2 phenotype indicate that the AID C-terminal region may be involved in DNA repair machinery required for CSR.  相似文献   
66.
Intrabiliary growth of liver metastases from colorectal cancer has rarely been studied. A surgically resected case of a metastatic liver tumor with prominent intrabiliary growth derived from rectal cancer is reported. The patient was a 62-year-old man who had received a low anterior resection for rectal cancer in March 2000. He was re-admitted due to obstructive jaundice in January 2003, and was diagnosed with hepatic malignancy in segment II of the liver with an intrabiliary tumor extending from the intrahepatic bile duct of segment II to the common hepatic duct. He underwent a left hepatectomy, a partial resection of segment VI, and an extrahepatic bile duct resection with reconstruction of the biliary tract. In the resected specimen, there were whitish tumors of 3 cm and 1.5 cm in diameter in segments II and VI, respectively, and an intrabiliary tumor originating from the main tumor in segment II extended to the common hepatic duct. Both the liver tumors and the intrabiliary tumor consisted of a well- to moderately differentiated adenocarcinoma, which showed the same histological features as the rectal cancer. The immunohistochemical findings strongly supported that these tumors, including the intrabiliary growth, were liver metastasis from the rectal cancer. The intrabiliary invasion and growth of metastatic liver tumors has generally been overlooked, notwithstanding their frequently observed biological behavior. The present case is informative, and further investigation into this type of metastatic liver tumor may be warranted.  相似文献   
67.
The Fas (CD95)/Fas ligand (CD178) system plays an important role in epithelial damage during the acute respiratory distress syndrome. The goal of this study was to determine whether proximal and distal human lung epithelial cells differ in their sensitivity to Fas ligand (rh-sFasL), and whether the response of lung epithelium to Fas ligation is modulated by proinflammatory cytokines. Although the expression of both Fas message and protein was similar in proximal and distal lung epithelial cells, only distal cells became apoptotic when exposed to serial dilutions of rh-sFasL. Stimulation with tumor necrosis factor-alpha, interleukin-1beta, or interferon-gamma significantly increased the sensitivity of proximal cells to rh-sFasL, and exposure to either tumor necrosis factor-alpha or interferon-gamma enhanced the sensitivity of distal cells to Fas ligation. These findings suggest that in normal human lungs, the responses of the epithelium to Fas ligation become more pronounced from proximal to distal locations. Furthermore, proinflammatory cytokines sensitize lung epithelium to Fas-induced death. These findings are relevant for understanding the role of the Fas/FasL system in acute lung injury, in which epithelial damage occurs primarily in distal airway and alveolar epithelium, whereas sFasL is present throughout the airspaces.  相似文献   
68.
AIMS: To investigate histopathological characteristics of melanocytic lesions affecting mucous membranes in various anatomical sites. Particular attention was paid to elucidation of morphological characteristics of early phases of mucosal melanoma in order to contribute to effective detection of this highly malignant neoplasm in the curable stages. METHODS: A total of 87 melanocytic lesions of mucous membranes were investigated histopathologically. There were 55 malignant melanomas including eight lesions of melanoma in situ, three in the radial growth phase (RGP) and 44 in the vertical growth phase (VGP), and 28 benign melanocytic lesions including four melanotic macules, 19 melanocytic naevi and five blue naevi. In addition, this series also included four equivocal lesions for which diagnoses were not definitely determined. With regard to malignant melanoma, histopathological patterns of in situ phase and RGP were intensely evaluated. RESULTS: Histopathological features of benign melanocytic lesions were essentially the same as those of the corresponding lesions of the skin. In the vast majority of mucosal melanomas, irrespective of anatomical sites, the main histopathological pattern seen in melanoma in situ and in RGP was the lentiginous pattern, which shows proliferation of atypical melanocytes in the lower layer of more or less acanthotic epithelium, though subtle variations of the pattern were detected. No association of melanocytic naevus was detected in any cases of melanoma. Based on these findings, we have proposed a unifying concept of de novo histogenesis of mucosal malignant melanoma. CONCLUSIONS: Our concept of histogenesis of mucosal melanoma assists in the identification of this highly malignant neoplasm in the early curable stages.  相似文献   
69.
Previous studies have shown that Peyer's patches (PP) are not required for intestinal immunoglobulin A (IgA) responses to orally administered soluble protein. However, the roles of PP in regulation of mucosal immune responses against bacterial antigen remain to be clarified. In the present study, we generated several gut-associated lymphoreticular tissue-null mice by treatment with anti-interleukin-7 receptor antibody, the fusion protein of lymphotoxin β receptor and IgG Fc, and/or tumor necrosis factor receptor p55 and IgG Fc. These mice were then immunized with recombinant Salmonella expressing the C fragment of the tetanus toxin (rSalmonella-Tox C). Orally immunized PP-null mice as well as isolated lymphoid follicle (ILF)-null, PP/ILF-null, and PP/ILF/mesenteric lymph node-null mice induced identical levels of tetanus toxoid (TT)-specific systemic IgG responses to those of control mice. However, PP-null mice, but not ILF-null mice, failed to induce TT-specific intestinal IgA antibodies. Analysis of TT-specific CD4+ T-cell responses showed a reduction of gamma interferon (IFN-γ) synthesis in the intestinal lamina propriae of PP-null mice given oral rSalmonella-Tox C. In contrast, TT-specific IFN-γ responses in the spleen and delayed-type hypersensitivity responses were intact in those immunized mice. Interestingly, Salmonella lipopolysaccharide (LPS)-specific fecal IgA responses were not elicited in PP-null mice, while serum IgG anti-LPS antibodies were identical to those of control mice. These results suggest that while none of the gut-associated lymphoreticular tissues are required for the induction of systemic immune responses, PP are an essential lymphoid tissue for induction and regulation of intestinal IgA immunity against orally administered rSalmonella.  相似文献   
70.

Purpose

Wedging of the vertebral body on radiological examination is a valuable indicator of a vertebral compression fracture, although it can also be observed in subjects with no history of trauma. The purpose of this study was to elucidate the normative value of vertebral wedging at the thoracolumbar junction in asymptomatic healthy subjects for differential diagnosis of vertebral compression fractures using MRI.

Methods

A total of 115 subjects without back pain at the time of the examination and without history of spinal trauma was included (68 males, 47 females, mean age 49.5?years). They underwent MRI of the thoracic and lumbar spine, and the ratio of anterior vertical height to posterior vertical height of the vertebral body (APR) was determined from T10 to L2 on T2 weighted sagittal images.

Results

APR was 0.92?±?0.08 at T10, 0.92?±?0.08 at T11, 0.90?±?0.06 at T12, 0.89?±?0.06 at L1, and 0.90?±?0.07 at L2, indicating that vertebral bodies at the thoracolumbar junction appear wedge-shaped rather than rectangular. Males, thinner subjects, smokers, and subjects with abnormalities of the endplates such as a Schmorl nodule had a significantly smaller APR than females, fatter subjects, non-smokers, and those without endplate abnormalities.

Conclusion

The normative values of APR obtained in the present study can represent a valuable reference in the diagnosis of vertebral compression fracture to help prevent confusion with physiological vertebral wedging.  相似文献   
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