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151.
Malakoplakia is a rare form of chronic granulomatous inflammation in mammals, and usually affects the urinary tract in humans. In this report, we present a case of granulomatous nephritis consistent with malakoplakia in a 4-year-old male cynomolgus monkey. Gross examination showed that the kidney was markedly enlarged and adhered to the surrounding organs. Histology showed that there was diffuse interstitial infiltration of histiocytes with abundant foamy eosinophilic cytoplasm resembling von Hansemann cells, PAS-positive granular cytoplasm and occasional PAS- and iron-positive intracellular small inclusion bodies. Electron microscopy showed that these histiocytes contained abundant lysosomes and phagolysosomes but no obvious Michaelis-Gutmann bodies. Based on these findings, a diagnosis of granulomatous nephritis consistent with early malakoplakia was made. This is the first report in a monkey of a renal lesion consistent with malakoplakia.  相似文献   
152.
The effects of bisphenol A (BPA) on placentation have not been fully determined. The aim of this study was to clarify the structural changes of the placenta, abortion rate, and survival of neonates after BPA administration in mice. BPA (10 mg/kg/day) was administered to pregnant mice (BPA mice) subcutaneously from the first day of pregnancy (Day 0) to Day 7 (8 days total). The number of embryos and weights of whole uteri were measured on Days 10 and 12. Morphological changes in the placentae were examined by light microscopy on the corresponding days of pregnancy. The number of neonates was also counted. Survival rates were periodically calculated for neonates from the first day after parturition (P-Day 0) to P-Day 56. The number of embryos and weight of the uterus on Days 10 and 12 were significantly decreased by BPA injection. No notable differences were recognized between the left and right uteri. The proportion of the labyrinthine zone per whole placenta in the BPA mice became lower than that in the controls, and that of the metrial gland was higher in the BPA mice. The intervillous spaces of the placenta were narrower in the BPA mice. Degenerative changes were found in the trophoblastic giant cells and spongiotrophoblast layers of the BPA mice. The number of BPA mouse neonates was drastically decreased within 3 days after birth, and no mice survived after P-Day 56. The results suggest that BPA not only disrupts placental functions and leads to abortion through chronic stimulation of gene expression by binding to DNA but that it also affects the mortality of neonates through indirect exposure of embryos.  相似文献   
153.
Cutaneous mastocytosis, which resembles a subset of urticaria pigmentosa in humans, is rare in dogs. We herein report unrepresentative neoplastic proliferation of mast cells in ventral skin removed routinely from a nine-month-old female laboratory beagle dog at necropsy. A histological examination revealed diffuse extensive cellular infiltration from the superficial to deep dermis in most parts of the skin around the fourth and fifth mammary papilla without nodule formation. Tumor cells were fairly monomorphic, well-differentiated mast cells with round nuclei of small distinct nucleoli and moderate to abundant, slightly eosinophilic and granular cytoplasm. A perivascular arrangement of mast cells was noted at the margin of the lesions. Infiltration of eosinophils and degeneration of collagen were not observed in the dermis. Cutaneous mastocytosis was diagnosed based on these features. A sequence analysis of lesions revealed the deletion of Gln555 to Ile570 within the juxtamembrane domain of c-kit (exon 11).  相似文献   
154.
 Two nucleoside triphosphatase (NTPase) cDNA clones were isolated from a cDNA library of Pisum sativum L., cv. Midoriusui. The genes encoding the cDNAs were designated PsAPY1 and PsAPY2. PsAPY1 included the N-terminal amino acid sequence of an NTPase bound to pea cell wall. The phylogenic analysis indicated that PsAPY1 belongs to an NTPase subfamily responsive to environmental stimuli and that PsAPY2 belongs to a discrete subfamily, the physiological role of which is almost unknown. The adenosine triphosphatase activity of recombinant PsAPY1 was regulated by an elicitor and a suppressor from the pea pathogen Mycosphaerella pinodes. Based on these findings, we discuss the role of NTPases in response to biological stresses. Received: May 27, 2002 / Accepted: July 31, 2002  相似文献   
155.
Two dogs were diagnosed with myotonia associated with hyperadrenocorticism and treated with trilostane. One dog showed temporary improvement, but the other dog showed no improvement. The dogs survived 2383 and 1902 days, respectively. Findings suggest that myotonia persists despite treatment, but this condition is not associated with a poor prognosis for survival.  相似文献   
156.
Blue native PAGE analysis for cell wall proteins from pea epicotyls demonstrated that cell wall-associated ecto-apyrase (ATPase) formed a large protein complex(es) ranging from 450 to 900?kDa; one of the components of the complex was copper amine oxidase (CuAO), which catalyzes the oxidation of amines with the subsequent generation of ammonia and hydrogen peroxide. CuAO activity was coordinately regulated in vitro with ATP-hydrolyzing activity by an elicitor and a suppressor from Mycosphaerella pinodes. Moreover, treatment of cell wall proteins with the suppressor caused the appearance of the apyrase monomer. On the basis of these results, M. pinodes may target the apyrase-containing protein complex(es) of the host to attenuate cell wall-based, extracellular defense(s) including the production of hydrogen peroxide.  相似文献   
157.
During the spring of 2001, approximately 10 000 yellow passion flower plants, from two orchards in the county of Livramento de Nossa Senhora, Bahia State, Brazil, exhibited intense yellow mosaic symptoms and drastic reduction of the leaf lamina and plant development. A large population of whiteflies ( Bemisia tabaci ) was also found colonizing the plants. All field samples collected tested positive for Passion fruit woodiness virus in DAS-ELISA. Five out of 20 passion flower plants inoculated with adult whiteflies collected from diseased plants in the field developed symptoms 20–30 days after inoculation. Two of these plants gave a positive reaction in TAS-ELISA using antiserum against a begomovirus. Degenerated PCR primers amplified viral DNA fragments from the DNA-A and DNA-B components of a begomovirus infecting these plants. The fragment corresponding to the core region of the coat protein (DNA-A) was cloned and sequenced. A phylogenetic analysis placed this begomovirus isolated from passion flower in the same clade of the New World begomoviruses as several other species from Brazil. Based on the symptoms induced by this virus alone, the disease was tentatively named passion flower little leaf mosaic.  相似文献   
158.
To initiate defense responses against invasion of pathogenic organisms, animals and plants must recognize microbe-associated molecular patterns (MAMPs). In this study, the elicitor activity of bacterial DNA on the model plant Arabidopsis thaliana was examined. EcoRI-digested plasmid DNA induced defense responses such as generation of reactive oxygen species and deposition of callose, whereas SmaI- and HapII-digested plasmid DNA and EcoRI-digested herring DNA did not remarkably induce these responses. Further, methylation of the CpG sequence of plasmid DNA and Escherichia coli DNA reduced the level of the defense responses. The endocytosis inhibitors wortmannin and amantadine significantly inhibited DNA-induced defense responses. These results suggest that non-methylated CpG DNA, as a MAMP, induced defense responses in Arabidopsis and that non-methylated DNA seems to be translocated into the cytoplasm by endocytosis.  相似文献   
159.
160.
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