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The objectives of this study were to evaluate morphologic, histochemical, and immunohistochemical characteristics of well-differentiated and anaplastic intraocular neoplasms of cats, and to develop a diagnostic algorithm for, and investigate the association of ruptured lenses with these neoplasms. Seventy-five feline globes with intraocular neoplasms were stained with hematoxylin and eosin and examined by light microscopy. Morphologic diagnoses included 33 intraocular sarcomas, 17 diffuse iris melanomas, 15 lymphosarcomas, three ciliary adenomas, one metastatic carcinoma, and six undifferentiated intraocular neoplasms. Sections of these globes were then stained with periodic acid Schiff (PAS), and immunohistochemical (IHC) labels for various cellular markers. Histochemical staining and IHC labeling confirmed cellular differentiation in 73/75 neoplasms but was discordant with morphologic diagnoses in 8/75. These included four neoplasms morphologically diagnosed as lymphosarcomas but which expressed differentiation antigens consistent with melanoma (n = 3) or ciliary adenocarcinoma (n = 1), and four tumors morphologically diagnosed as intraocular sarcomas that expressed differentiation antigens for melanoma (n = 2), metastatic carcinoma (n = 1), or remained undifferentiated (n = 1). Immunohistochemical labeling suggested a diagnosis in 5/6 morphologically undifferentiated neoplasms including one intraocular sarcoma, two diffuse iridal melanomas, and two ciliary adenocarcinomas. Based upon morphologic, histochemical, and IHC characterization, ruptured lens capsules were detected in 28/30 intraocular sarcomas, 3/24 diffuse iris melanomas and 1/11 lymphosarcomas, but not in ciliary epithelial neoplasms, metastatic carcinomas, or undifferentiated intraocular neoplasms. An algorithm is provided that facilitates stain and IHC label selection for differentiating anaplastic intraocular feline neoplasms. 相似文献
995.
Casrouge A Zhang SY Eidenschenk C Jouanguy E Puel A Yang K Alcais A Picard C Mahfoufi N Nicolas N Lorenzo L Plancoulaine S Sénéchal B Geissmann F Tabeta K Hoebe K Du X Miller RL Héron B Mignot C de Villemeur TB Lebon P Dulac O Rozenberg F Beutler B Tardieu M Abel L Casanova JL 《Science (New York, N.Y.)》2006,314(5797):308-312
Herpes simplex virus-1 (HSV-1) encephalitis (HSE) is the most common form of sporadic viral encephalitis in western countries. Its pathogenesis remains unclear, as it affects otherwise healthy patients and only a small minority of HSV-1-infected individuals. Here, we elucidate a genetic etiology for HSE in two children with autosomal recessive deficiency in the intracellular protein UNC-93B, resulting in impaired cellular interferon-alpha/beta and -lambda antiviral responses. HSE can result from a single-gene immunodeficiency that does not compromise immunity to most pathogens, unlike most known primary immunodeficiencies. Other severe infectious diseases may also reflect monogenic disorders of immunity. 相似文献
996.
Safety assessment of cre recombinase 总被引:1,自引:0,他引:1
Hileman RE Bonner HK Kaempfe TA Hammond BG Glenn KC 《Journal of agricultural and food chemistry》2006,54(22):8640-8647
Cre recombinase, when used as a tool in agricultural biotechnology, can precisely excise DNA sequences that may be useful in the introduction of a new trait but are not needed in the commercial product. Although the cre genetic material would not be present in the final product, the present studies were performed to assess the safety of Cre recombinase to provide confirmatory evidence of the safe use of Cre-lox technology in agricultural biotechnology. Cre recombinase shares no relevant sequence similarity to known allergens or toxins. When Cre recombinase was exposed to a pH 1.2 solution of simulated gastric fluid lacking pepsin, CD spectroscopy showed that there was a loss of secondary structure and that the protein was no longer active in a functional assay. Cre recombinase was degraded rapidly when exposed to pepsin in a standardized gastric digestion model; therefore, Cre recombinase would not survive the harsh gastric environment. When orally administered to mice as an acute dosage of 53 mg/kg of body weight, no treatment-related adverse findings were observed. These data support the conclusion that human and animal dietary exposure to Cre recombinase pose no known safety concerns; consistent with the fact that bacteriophage P1, the source of the cre gene and expressed protein, is commonly encountered in the environment and in normal enteric bacteria without reports of adverse consequences. 相似文献
997.
Ubiquitinated TDP-43 in frontotemporal lobar degeneration and amyotrophic lateral sclerosis 总被引:4,自引:0,他引:4
Neumann M Sampathu DM Kwong LK Truax AC Micsenyi MC Chou TT Bruce J Schuck T Grossman M Clark CM McCluskey LF Miller BL Masliah E Mackenzie IR Feldman H Feiden W Kretzschmar HA Trojanowski JQ Lee VM 《Science (New York, N.Y.)》2006,314(5796):130-133
Ubiquitin-positive, tau- and alpha-synuclein-negative inclusions are hallmarks of frontotemporal lobar degeneration with ubiquitin-positive inclusions and amyotrophic lateral sclerosis. Although the identity of the ubiquitinated protein specific to either disorder was unknown, we showed that TDP-43 is the major disease protein in both disorders. Pathologic TDP-43 was hyper-phosphorylated, ubiquitinated, and cleaved to generate C-terminal fragments and was recovered only from affected central nervous system regions, including hippocampus, neocortex, and spinal cord. TDP-43 represents the common pathologic substrate linking these neurodegenerative disorders. 相似文献
998.
Scott R. Hutson Aline Magnoni Timothy Beach Richard E. Terry Bruce H. Dahlin Mary Jo Schabel 《CATENA》2009,78(3):260
As time passes, phosphorus (P) in soils tends to become more tightly bound with minerals. Phosphate fractionation enables the measurement of loosely versus tightly bound P. Archaeologists have used P fractionation as a chronometric technique: older soils should have greater proportions of P tightly bound with minerals. Research at Chunchucmil, a large Maya ruin in Yucatan, Mexico, has used extractable P concentrations and other lines of evidence to investigate ancient uses of space. Because contemporary Maya villagers use the land among the Chunchucmil ruins in a number of ways, and because the ancient land surfaces are neither sealed nor deeply buried, we used P fractionation to determine whether geochemical signatures of activities such as gardening resulted from ancient or modern inhabitants. The fractionation results at Chunchucmil are unusual in comparison to studies from other sites. Furthermore, there are strong correlations between the sum of P fractions and carbonate. We discuss potential explanations for these patterns in P fractionation data. These explanations consider local pedology, differential length of ancient occupation, and localized dumping of the byproducts of maize processing. To examine the chemical signatures of maize processing, specifically soaking maize in lime water, contemporary samples of sediments and residues from this activity were analyzed. Our results suggest that dumping water from maize soaking provides a potential explanation for the ancient P patterns. 相似文献
999.
Invasive earthworms can have significant impacts on C dynamics through their feeding, burrowing, and casting activities, including the protection of C in microaggregates and alteration of soil respiration. European earthworm invasion is known to affect soil micro- and mesofauna, but little is known about impacts of invasive earthworms on other soil macrofauna. Asian earthworms (Amynthas spp.) are increasingly being reported in the southern Appalachian Mountains in southeastern North America. This region is home to a diverse assemblage of native millipedes, many of which share niches with earthworm species. This situation indicates potential for earthworm-millipede competition in areas subject to Amynthas invasion.In a laboratory microcosm experiment, we used two 13C enriched food sources (red oak, Quercus rubra, and eastern hemlock, Tsuga canadensis) to assess food preferences of millipedes (Pseudopolydesmus erasus), to determine the effects of millipedes and earthworms (Amynthas corticis) on soil structure, and to ascertain the nature and extent of the interactions between earthworms and millipedes. Millipedes consumed both litter species and preferred red oak litter over eastern hemlock litter. Mortality and growth of millipedes were not affected by earthworm presence during the course of the experiment, but millipedes assimilated much less litter-derived C when earthworms were present.Fauna and litter treatments had significant effects on soil respiration. Millipedes alone reduced CO2 efflux from microcosms relative to no fauna controls, whereas earthworms alone and together with millipedes increased respiration, relative to the no fauna treatment. CO2 derived from fresh litter was repressed by the presence of macrofauna. The presence of red oak litter increased CO2 efflux considerably, compared to hemlock litter treatments.Millipedes, earthworms, and both together reduced particulate organic matter. Additionally, earthworms created significant shifts in soil aggregates from the 2000-250 and 250-53 μm fractions to the >2000 μm size class. Earthworm-induced soil aggregation was lessened in the 0-2 cm layer in the presence of millipedes. Earthworms translocated litter-derived C to soil throughout the microcosm.Our results suggest that invasion of ecosystems by A. corticis in the southern Appalachian Mountains is unlikely to be limited by litter species and these earthworms are likely to compete directly for food resources with native millipedes. Widespread invasion could cause a net loss of C due to increased respiration rates, but this may be offset by C protected in water-stable soil aggregates. 相似文献
1000.
The brown marmorated stink bug. Halyomorpha halys, (BMSB) is an exotic pest causing damage to fruits and vegetables. They also transmit diseases. Integrated pest management strategies are lacking for this invasive. For the first time, information is presented on the virulence of several entomopathogenic fungi against BMSB. Three Beauveria bassiana and two Metarhizium anispoliae isolates were bioassayed against adult BMSB. One B. bassiana isolate was the active ingredient in BotaniGard® which produced 85 and 100% mortality in 9 and 12 days post treatment, respectively. Experimental isolates ERL 1170 and ERL 1540 were also efficacious. Metarhizium anispoliae isolates produced lower mortalities than the B. bassiana isolates. Data presented showed the potential for management of BMSB with entomopathogenic fungi. Copyright © 2012 Society of Chemical Industry 相似文献