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1.
Appl Opt ; 62(11): 2827-2834, 2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-37133125

RESUMO

Although a reflective optical system can theoretically realize ideal optical designs, it is not always the optimal choice compared with a refractive one because of the difficulty in achieving high wavefront accuracy. A promising solution is to build reflective optical systems by mechanically assembling all the optical and structural components made of cordierite, which is a ceramic with a very low thermal expansion coefficient. Interferometric evaluations of an experimental product demonstrated that diffraction-limited performance in the visible wavelength was achieved and maintained even after cooling to 80 K. This new technique may be the most cost-effective method for utilizing reflective optical systems, especially for cryogenic applications.

2.
Appl Opt ; 54(16): 5193-202, 2015 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-26192683

RESUMO

An immersion grating composed of a transmissive material with a high refractive index (n>2) is a powerful device for high-resolution spectroscopy in the infrared region. Although the original idea is attributed to Fraunhofer about 200 years ago, an immersion grating with high diffraction efficiency has never been realized due to the difficulty in processing infrared crystals that are mostly brittle. While anisotropic etching is one successful method for fabricating a fine groove pattern on Si crystal, machining is necessary for realizing the ideal groove shape on any kind of infrared crystal. In this paper, we report the realization of the first, to the best of our knowledge, machined immersion grating made of single-crystal CdZnTe with a high diffraction efficiency that is almost identical to that theoretically predicted by rigorous coupled-wave analysis.

4.
Biogerontology ; 14(1): 73-87, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23291976

RESUMO

Lactobacilli and bifidobacteria are probiotic bacteria that modify host defense systems and have the ability to extend the lifespan of the nematode Caenorhabditis elegans. Here, we attempted to elucidate the mechanism by which bifidobacteria prolong the lifespan of C. elegans. When the nematode was fed Bifidobacterium infantis (BI) mixed at various ratios with the standard food bacterium Escherichia coli strain OP50 (OP), the mean lifespan of worms was extended in a dose-dependent manner. Worms fed BI displayed higher locomotion and produced more offspring than control worms. The growth curves of nematodes were similar regardless of the amount of BI mixed with OP, suggesting that BI did not induce prolongevity effects through caloric restriction. Notably, feeding worms the cell wall fraction of BI alone was sufficient to promote prolongevity. The accumulation of protein carbonyls and lipofuscin, a biochemical marker of aging, was also lower in worms fed BI; however, the worms displayed similar susceptibility to heat, hydrogen peroxide, and paraquat, an inducer of free radicals, as the control worms. As a result of BI feeding, loss-of-function mutants of daf-16, jnk-1, aak-2, tol-1, and tir-1 exhibited a longer lifespan than OP-fed control worms, but BI failed to extend the lifespan of pmk-1, skn-1, and vhp-1 mutants. As skn-1 induces phase 2 detoxification enzymes, our findings suggest that cell wall components of bifidobacteria increase the average lifespan of C. elegans via activation of skn-1, regulated by the p38 MAPK pathway, but not by general activation of the host defense system via DAF-16.


Assuntos
Bifidobacterium/fisiologia , Caenorhabditis elegans/microbiologia , Caenorhabditis elegans/fisiologia , Longevidade/fisiologia , Envelhecimento/fisiologia , Animais , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Restrição Calórica , Dieta , Escherichia coli/fisiologia , Genes de Helmintos , Lipofuscina/metabolismo , Mutação , Carbonilação Proteica , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
5.
Acta Derm Venereol ; 90(6): 621-4, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21057747

RESUMO

Linear IgA/IgG bullous dermatosis (LAGBD) is an auto-immune blistering disease characterized by the local accumulation of IgA- and IgG-class anti-basement membrane autoantibodies. It typically presents as a generalized pruritic vesiculobullous eruption. No cases of localized LAGBD have yet been reported. We report a case of a 78-year-old man with LAGBD localized to the perianal area. The patient complained of suffering from persistent ulcers around the anus for more than 3 years. Physical examination revealed several blisters and ulcers up to 2-cm in diameter around the anus. No lesions were found elsewhere on the body. Histological analysis of a skin biopsy revealed subepidermal blistering, while direct immunofluorescence showed the linear deposition of IgA and IgG antibodies at the dermoepidermal junction. Indirect immunofluorescence of normal human skin whose layers had been separated using 1M NaCl showed the binding of both IgA and IgG to the epidermal side. Immunoblotting demonstrated the presence of circulating IgA and IgG autoantibodies that bound to a 120-kDa protein. This is the first case of localized LAGBD whose skin lesions were restricted to the perianal region.


Assuntos
Autoanticorpos/sangue , Autoantígenos/imunologia , Vesícula/imunologia , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Colágenos não Fibrilares/imunologia , Dermatopatias Vesiculobolhosas/imunologia , Úlcera Cutânea/imunologia , Pele/imunologia , Administração Oral , Idoso , Canal Anal , Biópsia , Vesícula/tratamento farmacológico , Vesícula/patologia , Dapsona/administração & dosagem , Técnica Direta de Fluorescência para Anticorpo , Técnica Indireta de Fluorescência para Anticorpo , Glucocorticoides/administração & dosagem , Humanos , Immunoblotting , Masculino , Prednisolona/administração & dosagem , Pele/efeitos dos fármacos , Pele/patologia , Dermatopatias Vesiculobolhosas/tratamento farmacológico , Dermatopatias Vesiculobolhosas/patologia , Úlcera Cutânea/tratamento farmacológico , Úlcera Cutânea/patologia , Resultado do Tratamento , Colágeno Tipo XVII
6.
Appl Environ Microbiol ; 76(12): 4105-8, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20418445

RESUMO

The survival times of Caenorhabditis elegans worms infected with Legionella pneumophila from day 7.5 or later after hatching were shorter than those of uninfected worms. However, nematodes fed bifidobacteria prior to Legionella infection were resistant to Legionella. These nematodes may act as a unique alternative host for Legionella research.


Assuntos
Antibiose , Bifidobacterium/fisiologia , Caenorhabditis elegans/microbiologia , Legionella pneumophila/crescimento & desenvolvimento , Legionella pneumophila/patogenicidade , Animais , Bifidobacterium/crescimento & desenvolvimento , Bifidobacterium/metabolismo , Contagem de Colônia Microbiana , Modelos Animais de Doenças , Análise de Sobrevida , Fatores de Tempo
9.
J Am Acad Dermatol ; 57(5 Suppl): S115-7, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17938020

RESUMO

Adult T-cell leukemia/lymphoma (ATLL) often involves the skin. Cases with skin lesions without either leukemic nor lymph node involvement have been categorized into a cutaneous type. While the clinical manifestations of the cutaneous-type ATLL are variable, including multiple papules, nodules, plaques, or erythroderma, a solitary skin nodule alone is rare, and only 2 cases have been reported in the literature. We present a 58-year-old Japanese patient with cutaneous-type ATLL that presented as a large, solitary skin nodule as the sole clinical feature. The skin tumor was completely resolved after treatment with x-ray and electron beam irradiation.


Assuntos
Leucemia-Linfoma de Células T do Adulto/patologia , Neoplasias Cutâneas/patologia , Humanos , Leucemia-Linfoma de Células T do Adulto/radioterapia , Masculino , Pessoa de Meia-Idade , Indução de Remissão , Neoplasias Cutâneas/radioterapia , Terapia por Raios X
10.
Appl Environ Microbiol ; 73(20): 6404-9, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17704266

RESUMO

This study aimed to develop a convenient model to investigate the senescence of host defenses and the influence of food and nutrition. A small soil nematode, Caenorhabditis elegans, was grown for 3 days from hatching on a lawn of Escherichia coli OP50 as the normal food source, and subsequently some of the nematodes were fed lactic acid bacteria (LAB). The life spans of worms fed LAB were significantly longer than the life spans of those fed OP50. To investigate the effect of age on host defenses, 3- to 7-day-old worms fed OP50 were transferred onto a lawn of Salmonella enterica serovar Enteritidis for infection. The nematodes died over the course of several days, and the accumulation of salmonella in the intestinal lumen suggested that the worms were infected. The 7-day-old worms showed a higher death rate during the 5 days after infection than nematodes infected at the age of 3 days; no clear difference was observed when the worms were exposed to OP50. We then investigated whether the LAB could exert probiotic effects on the worms' host defenses and improve life span. Seven-day-old nematodes fed LAB from the age of 3 days were more resistant to salmonella than worms fed OP50 until they were infected with salmonella. This study clearly showed that LAB can enhance the host defense of C. elegans and prolong life span. The nematode appears to be an appropriate model for screening useful probiotic strains or dietetic antiaging substances.


Assuntos
Bifidobacterium/crescimento & desenvolvimento , Caenorhabditis elegans/crescimento & desenvolvimento , Caenorhabditis elegans/microbiologia , Lactobacillus/crescimento & desenvolvimento , Salmonella enteritidis/patogenicidade , Ração Animal , Animais , Escherichia coli/crescimento & desenvolvimento , Ácido Láctico/metabolismo , Salmonella enteritidis/crescimento & desenvolvimento
13.
J Am Acad Dermatol ; 50(1): 126-9, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14699382

RESUMO

Elastofibroma is an uncommon fibroelastic tumor or tumorlike process that usually occurs between the scapula and the chest wall of elderly patients. This condition is rarely reported in the dermatologic literature, because it infrequently arises in the skin or within the subcutaneous tissue. We present a 78-year-old man with 15 separate subcutaneous nodules on the buttocks and upper extremities together with bilateral subscapular nodules. All specimens taken from different lesions were histologically confirmed as elastofibromas. As far as we know, this case with 17 distinct elastofibromas demonstrates the largest number ever reported in a single patient. Although the pathomechanism of the occurrence of multiple elastofibromas is unknown, it should be included in the differential diagnosis of multiple subcutaneous nodules.


Assuntos
Fibroma/patologia , Neoplasias Primárias Múltiplas/patologia , Neoplasias Cutâneas/patologia , Idoso , Humanos , Masculino
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