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101.
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   
102.
Pancreatic anaplastic carcinoma (PAC) is rare and has an aggressive clinical course. We report an autopsy case of PAC focusing on the cytopathological characteristics of the tumor and immunocytochemical staining for vimentin, E‐cadherin, and zinc finger E‐box binding homeobox 1 (ZEB1), which markers are associated with epithelial markers of epithelial‐mesenchymal transition (EMT). A 50‐year‐old woman presented to our hospital with a chief complaint of jaundice. A pancreatic head tumor and multiple liver nodules were detected on abdominal computed tomography. Biliary cytology under endoscopic retrograde cholangiopancreatography suggested ductal adenocarcinoma. Three months after admission, she died of multiorgan failure. At autopsy, touch imprint cytology using squash preparation of the pancreatic tumor identified two different cell types; numerous isolated malignant cells with large and pleomorphic nuclei and a few clusters showing irregularly overlapped nuclei and irregular contours within the necrotic background. Immunocytochemically, isolated cells were positive for vimentin and ZEB1, and negative for E‐cadherin. Conversely, clusters were negative for vimentin and ZEB1, and positive for E‐cadherin. Histologically, the tumor was composed of sarcomatous cells with small foci of adenocarcinoma, which were consistent with a diagnosis of PAC. Immunohistochemical staining of the adenocarcinoma and sarcomatous cells corresponded to those of the clusters and isolated malignant cells, respectively. Immunostaining of these EMT markers is useful to distinguish sarcomatous cells from adenocarcinoma and can contribute to the accurate diagnosis of pancreatic tumors with EMT.  相似文献   
103.
104.
Autologous stem cell transplantation (ASCT) is a treatment option for HIV-positive patients with non-Hodgkin lymphoma (NHL) and multiple myeloma (MM). However, the prognosis after ASCT in HIV-positive Japanese patients remains unclear. The aim of this study was to evaluate the impact of HIV infection on transplant outcomes after ASCT in Japan. Using the national database of the Japan Society for Hematopoietic Cell Transplantation, we retrospectively evaluated patients with NHL (n?=?3862) and MM (n?=?2670) who underwent their first ASCT between 2001 and 2014. The presence of HIV antibody was used to diagnose HIV infection. Fifty-six patients with NHL (1.4%) and 23 with MM (.8%) were positive for HIV antibody. Among patients with NHL overall survival (OS) was lower in HIV-positive patients than in HIV-negative patients (5-year OS: HIV-positive patients, 44% versus HIV-negative patients, 65%; P?<?.001). In a multivariate analysis HIV infection was significantly associated with an increased risk of overall mortality (hazard ratio, 2.30; P?<?.001). The incidence of relapse was higher in HIV-positive patients (P?=?.036), whereas there was a similar incidence of nonrelapse mortality (P?=?.879). OS in patients with MM was similar between those with/without HIV infection (5-year OS: HIV-positive patients, 61% versus HIV-negative patients, 63%; P?=?.988). HIV infection was associated with a higher risk of overall mortality and relapse after ASCT for NHL in a Japanese population.  相似文献   
105.
Many families of centromeric repetitive DNA sequences isolated from Struthioniformes, Galliformes, Falconiformes, and Passeriformes are localized primarily to microchromosomes. However, it is unclear whether chromosome size-correlated homogenization is a common characteristic of centromeric repetitive sequences in Aves. New World and Old World quails have the typical avian karyotype comprising chromosomes of two distinct sizes, and C-positive heterochromatin is distributed in centromeric regions of most autosomes and the whole W chromosome. We isolated six types of centromeric repetitive sequences from three New World quail species (Colinus virginianus, CVI; Callipepla californica, CCA; and Callipepla squamata, CSQ; Odontophoridae) and one Old World quail species (Alectoris chukar, ACH; Phasianidae), and characterized the sequences by nucleotide sequencing, chromosome in situ hybridization, and filter hybridization. The 385-bp CVI-MspI, 591-bp CCA-BamHI, 582-bp CSQ-BamHI, and 366-bp ACH-Sau3AI fragments exhibited tandem arrays of the monomer unit, and the 224-bp CVI-HaeIII and 135-bp CCA-HaeIII fragments were composed of minisatellite-like and microsatellite-like repeats, respectively. ACH-Sau3AI was a homolog of the chicken nuclear membrane repeat sequence, whose homologs are common in Phasianidae. CVI-MspI, CCA-BamHI, and CSQ-BamHI showed high homology and were specific to the Odontophoridae. CVI-MspI was localized to microchromosomes, whereas CVI-HaeIII, CCA-BamHI, and CSQ-BamHI were mapped to almost all chromosomes. CCA-HaeIII was localized to five pairs of macrochromosomes and most microchromosomes. ACH-Sau3AI was distributed in three pairs of macrochromosomes and all microchromosomes. Centromeric repetitive sequences may be homogenized in chromosome size-correlated and -uncorrelated manners in New World quails, although there may be a mechanism that causes homogenization of centromeric repetitive sequences primarily between microchromosomes, which is commonly observed in phasianid birds.  相似文献   
106.
107.
Respiratory syncytial virus (RSV) infection has been hypothesized to be a risk factor for the development of allergy and asthma, but epidemiologic studies in humans still remain inconclusive. The association between RSV infection and allergic diseases may be dependent on an atopic background and previous history of RSV infection. It has been reported that RSV infection before sensitization to an allergen decreased the production of Th2‐like cytokines in the lung and the levels of allergen‐specific Th2‐type antibodies in the serum. However, the underlying mechanisms are largely unknown. In the present study, the role of pulmonary γδ T cells in RSV‐affected, allergen‐induced airway inflammation was investigated. BALB/c mice were sensitized to or challenged with ovalbumin (OVA) and infected with RSV either before or after the sensitization period. It became clear that sensitization and challenge of mice with OVA induced a large influx of γδ T cells to the lungs. However, prior RSV infection inhibited the infiltration of γδ T cells as well as activated γδ T cells, characterized by expression of CD40L or CD69 molecular in the cell surface. Moreover, prior RSV infection elevated the type 1 cytokine gene expression but suppressed type 2 cytokine expression in the lung γδ T cells. Adoptive transfer of γδ T cells from OVA‐sensitized and challenged mice increased airway inflammation, suggesting that γδ T cells may play a proinflammatory role in allergic responses. These results described here support the idea of an unknown γδ T cell‐dependent mechanism in the regulation of RSV‐affected, allergen‐induced allergic airway responses. J. Med. Virol. 85:149–156, 2012. © 2012 Wiley Periodicals, Inc.  相似文献   
108.
We analyzed the genetic aberrations on chromosome arms 1p, 10q, and 14q, which are thought to be loci that include putative tumor suppressor genes in meningiomas. We initially conducted molecular genetic testing on a total of 72 tumors including 15 atypical and 8 anaplastic meningiomas using double-target fluorescence in situ hybridization. An incidence of deletion of 1p was observed in 16.3% of histologically benign, 86.7% of atypical, and 87.5% of anaplastic meningiomas. Microsatellite analysis for loss of heterozygosity on 1p, 10q, and 14q was performed in 15 tumors (6 benign, 6 atypical, and 3 anaplastic meningiomas). We detected a limited deleted region on 1p36 in two tumors and suggest a new consistent region of deletion at 1p36.21p23 distal to D1S507 and proximal to D1S214, which spans 8.21 megabases. In addition, loss of 10q was detected in two of three secondary atypical meningiomas, and loss of 14q in two of three primary anaplastic meningiomas. We suggest that one of the putative suppressor genes is located at 1p36.21p23, and that 10q loss may contribute to the malignant progression from benign to atypical meningiomas.  相似文献   
109.
The water monitor lizard (Varanus salvator macromaculatus (VSA), Platynota) has a chromosome number of 2n?=?40: its karyotype consists of 16 macrochromosomes and 24 microchromosomes. To delineate the process of karyotype evolution in V. salvator macromaculatus, we constructed a cytogenetic map with 86 functional genes and compared it with those of the butterfly lizard (Leiolepis reevesii rubritaeniata (LRE); 2n?=?36) and Japanese four-striped rat snake (Elaphe quadrivirgata (EQU); 2n?=?36), members of the Toxicofera clade. The syntenies and gene orders of macrochromosomes were highly conserved between these species except for several chromosomal rearrangements: eight pairs of VSA macrochromosomes and/or chromosome arms exhibited homology with six pairs of LRE macrochromosomes and eight pairs of EQU macrochromosomes. Furthermore, the genes mapped to microchromosomes of three species were all located on chicken microchromosomes or chromosome 4p. No reciprocal translocations were found in the species, and their karyotypic differences were caused by: low frequencies of interchromosomal rearrangements, such as tandem fusions, or centric fissions/fusions between macrochromosomes and between macro- and microchromosomes; and intrachromosomal rearrangements, such as paracentric inversions or centromere repositioning. The chromosomal rearrangements that occurred in macrochromosomes of the Varanus lineage were also identified through comparative cytogenetic mapping of V. salvator macromaculatus and V. exanthematicus. Morphologic differences in chromosomes 6–8 between the two species could have resulted from pericentric inversion or centromere repositioning.  相似文献   
110.
To elucidate the effects of teeth on muscle fibers in the tongue during the developmental process, we examined the expression of muscle contractile proteins and the genes for those proteins in normal mice and microphthalmic (mi/mi) mice with impaired tooth eruption. The mice were observed during the growth period, including weaning, which is when feeding movements undergo major changes. Expression of the myosin heavy chain (MyHC)-2a protein, whose contraction speed is relatively slow, disappeared after weaning in normal mice, while it remained in high concentrations even after weaning in mi/mi mice. The presence of MyHC-2a after weaning in mice with no tooth eruption was attributed to a compensation for lack of proper masticatory function and sucking-like movements, as MyHC-2a is necessary for these movements.  相似文献   
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