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1.
Phys Rev Lett ; 131(4): 041002, 2023 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-37566836

RESUMO

The LUX-ZEPLIN experiment is a dark matter detector centered on a dual-phase xenon time projection chamber operating at the Sanford Underground Research Facility in Lead, South Dakota, USA. This Letter reports results from LUX-ZEPLIN's first search for weakly interacting massive particles (WIMPs) with an exposure of 60 live days using a fiducial mass of 5.5 t. A profile-likelihood ratio analysis shows the data to be consistent with a background-only hypothesis, setting new limits on spin-independent WIMP-nucleon, spin-dependent WIMP-neutron, and spin-dependent WIMP-proton cross sections for WIMP masses above 9 GeV/c^{2}. The most stringent limit is set for spin-independent scattering at 36 GeV/c^{2}, rejecting cross sections above 9.2×10^{-48} cm at the 90% confidence level.

2.
J Prev Med Hyg ; 60(3): E256-E261, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31650063

RESUMO

OBJECTIVE: Cancers are one of the most important public health problems in Iran. Because of the importance of cancers, the purpose of the current study was to the prediction of the future incidence of the most common cancers among Iranian military community (MC) by using the time series analysis during 2007 to 2019. METHODS: In the current cross-sectional study, all registered cancers among Iranian MC entered the study. To select the best model of prediction, various methods including autocorrelation function (ACF), partial autocorrelation function (PACF), and Akaike information criterion (AIC) statistics were used. All analysis was performed by using ITSM, stata14, and Excel2010 software. RESULTS: The most prevalent cancers among Iranian MC were breast, prostate, and colon cancers respectively. The time series analysis was shown that the trend of all mentioned cancers in Iranian MC will increase in the coming years. CONCLUSIONS: The trend of most prevalent cancers among Iranian MC was increasing but the different factors like the growth of population size and improving the registration system should be regarded.


Assuntos
Neoplasias da Mama/epidemiologia , Neoplasias Colorretais/epidemiologia , Família Militar/estatística & dados numéricos , Militares/estatística & dados numéricos , Neoplasias da Próstata/epidemiologia , Veteranos/estatística & dados numéricos , Idoso , Feminino , Humanos , Incidência , Irã (Geográfico)/epidemiologia , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos
3.
Cell Death Dis ; 1: e24, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21364632

RESUMO

Inherited retinal degenerations, collectively termed retinitis pigmentosa (RP), constitute one of the leading causes of blindness in the developed world. RP is at present untreatable and the underlying neurodegenerative mechanisms are unknown, even though the genetic causes are often established. Acetylation and deacetylation of histones, carried out by histone acetyltransferases (HATs) and histone deacetylases (HDACs), respectively, affects cellular division, differentiation, death and survival. We found acetylation of histones and probably other proteins to be dramatically reduced in degenerating photoreceptors in the rd1 human homologous mouse model for RP. Using a custom developed in situ HDAC activity assay, we show that overactivation of HDAC classes I/II temporally precedes photoreceptor degeneration. Moreover, pharmacological inhibition of HDACs I/II activity in rd1 organotypic retinal explants decreased activity of poly-ADP-ribose-polymerase and strongly reduced photoreceptor cell death. These findings highlight the importance of protein acetylation for photoreceptor cell death and survival and propose certain HDAC classes as novel targets for the pharmacological intervention in RP.


Assuntos
Histona Desacetilases/metabolismo , Degeneração Neural/enzimologia , Degeneração Neural/patologia , Degeneração Retiniana/enzimologia , Degeneração Retiniana/patologia , Acetilação/efeitos dos fármacos , Animais , Morte Celular/efeitos dos fármacos , Citoproteção/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Inibidores de Histona Desacetilases/farmacologia , Histona Desacetilases/genética , Humanos , Isoenzimas/genética , Isoenzimas/metabolismo , Camundongos , Camundongos Mutantes , Análise de Sequência com Séries de Oligonucleotídeos , Células Fotorreceptoras de Vertebrados/efeitos dos fármacos , Células Fotorreceptoras de Vertebrados/enzimologia , Células Fotorreceptoras de Vertebrados/patologia , Poli(ADP-Ribose) Polimerases/metabolismo
4.
Cutan Ocul Toxicol ; 25(3): 185-94, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16980244

RESUMO

Unprotected dermal contact with weapons maintenance materials is highly probable during cleaning and maintenance of firearms. Several weapons maintenance materials of interest to the Department of Defense were evaluated for their irritating and sensitizing potential in a modified local lymph node assay (LLNA). Female BALB/c mice (n = 5) were topically exposed to Break-Free CLP, Royco 634, TW-25B, MC-25, or MC-2500. All compounds tested produced a positive response for irritancy and lymphocyte proliferation. Break-Free CLP and Royco 634 produced the greatest dermal irritation and highest LLNA stimulation index. Phenotyping of draining lymph node cells from animals treated with Break-Free CLP suggest that this material induces T-cell-mediated contact sensitization (Type IV hypersensitivity) in mice. These findings support the recommendation that persons handling or using weapons maintenance materials should protect their skin from repeated contact by wearing appropriate personal protective equipment.


Assuntos
Dermatite de Contato/etiologia , Irritantes/toxicidade , Óleos/toxicidade , Parafina/toxicidade , Pele/efeitos dos fármacos , Animais , Dermatite de Contato/patologia , Relação Dose-Resposta a Droga , Feminino , Luvas Protetoras , Ensaio Local de Linfonodo , Linfonodos/efeitos dos fármacos , Linfonodos/imunologia , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos BALB C , Medicina Naval , Pele/patologia
5.
Food Chem Toxicol ; 42(4): 649-58, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15019190

RESUMO

The seed coat extract of Tamarindus indica, a polyphenolic flavonoid, has been shown to have antioxidant properties. The present studies investigated the inhibitory effect of the seed coat extract of T. indica on nitric oxide production in vitro using a murine macrophage-like cell line, RAW 264.7, and in vitro and in vivo using freshly isolated B6C3F1 mouse peritoneal macrophages. In vitro exposure of RAW 264.7 cells or peritoneal macrophages to 0.2-200 microg/mL of T. indica extract significantly attenuated (as much as 68%) nitric oxide production induced by lipopolysaccharide (LPS) and interferon gamma (IFN-gamma) in a concentration-dependent manner. In vivo administration of T. indica extract (100-500 mg/kg) to B6C3F1 mice dose-dependently suppressed TPA, LPS and/or IFN-gamma induced production of nitric oxide in isolated mouse peritoneal macrophages in the absence of any effect on body weight. Exposure to T. indica extract had no effect on cell viability as assessed by the MTT assay. In B6C3F1 mice, preliminary safety studies demonstrated a decrease in body weight at only the highest dose tested (1000 mg/kg) without alterations in hematology, serum chemistry or selected organ weights or effects on NK cell activity. A significant decrease in body weight was observed in BALB/c mice exposed to concentrations of extract of 250 mg/kg or higher. Oral exposure of BALB/c mice to T. indica extract did not modulate the development of T cell-mediated sensitization to DNFB or HCA as measured by the local lymph node assay, or dermal irritation to nonanoic acid or DNFB. These studies suggest that in mice, T. indica extract at concentrations up to 500 mg/kg may modulate nitric oxide production in the absence of overt acute toxicity.


Assuntos
Macrófagos Peritoneais/efeitos dos fármacos , Óxido Nítrico/metabolismo , Extratos Vegetais/farmacologia , Sementes/química , Tamarindus , Administração Oral , Animais , Peso Corporal/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Combinação de Medicamentos , Feminino , Interferon gama/farmacologia , Lipopolissacarídeos/farmacologia , Linfonodos/efeitos dos fármacos , Linfonodos/metabolismo , Macrófagos Peritoneais/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Extratos Vegetais/administração & dosagem , Testes Cutâneos/métodos
6.
Urol J ; 1(2): 128-30, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-17874403
7.
Neuroreport ; 13(6): 745-50, 2002 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-11997680

RESUMO

In neonatal retinal explants cultured long-term green cones are missing. Recently it was reported that thyroid hormone beta2 receptors (TR-beta2) are essential for these green cones to differentiate. Therefore transcript level of these receptors was investigated in our mouse retinal explants. However, thyroid receptors function as heterodimers with retinoid receptors (RR); so the fate of selected RRs was similarly analyzed using semi-quantitative RT-PCR. Loss of TR-beta2 and RR (RXR-gamma and ROR-beta2) mRNAs was observed after culturing the neonatal retina for 12 days. This indicates that these proteins are involved in determination of green cone identity. In addition, levels of the selected RR transcripts are differentially affected by short- or long-term culture. In the latter case an attached retinal pigment epithelium seems to play a protective role. Furthermore, divergent diurnal peaks of RR mRNAs are present in young as well as aged mouse retina and neocortex. This data might be relevant in the context of human ageing disorders.


Assuntos
Regulação da Expressão Gênica/fisiologia , Neocórtex/crescimento & desenvolvimento , Receptores de Superfície Celular/genética , Receptores Citoplasmáticos e Nucleares , Receptores do Ácido Retinoico/genética , Receptores dos Hormônios Tireóideos/genética , Retina/crescimento & desenvolvimento , Fatores de Transcrição/genética , Envelhecimento/metabolismo , Animais , Diferenciação Celular/genética , Ritmo Circadiano/genética , Adaptação à Escuridão/genética , Regulação para Baixo/genética , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C3H , Neocórtex/citologia , Neocórtex/metabolismo , Membro 2 do Grupo F da Subfamília 1 de Receptores Nucleares , Técnicas de Cultura de Órgãos/métodos , RNA Mensageiro/metabolismo , Retina/citologia , Retina/metabolismo , Receptor alfa de Ácido Retinoico , Receptores X de Retinoides , Transcrição Gênica/fisiologia , Regulação para Cima/genética
8.
J Chem Neuroanat ; 22(4): 263-73, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11719023

RESUMO

The neonatal mouse retina remains viable as an explant in serum-supplemented growth media for more than 4 weeks. Interpretation of drug effects on this tissue is compromised by the enigmatic composition of the serum. We sought to remove this ambiguity by culturing neonatal as well as late postnatal mouse retina in serum-free nutrient medium. In this study three important observations were made, (1) there is histotypic development of neonatal as well as preservation of late postnatal mouse retinal structure during long-term culture in serum-free medium, although the late postnatal tissue tends to show some loss of cells in the outer nuclear layer. (2) Protein expression in explant photoreceptor cells was similar to that in the litter-matched ones, except for green cone opsin and interphotoreceptor retinoid-binding protein, although mRNA of the latter is present at similar amounts as in age-matched in vivo controls. (3) Cells of the inner retina stained by antibodies to calcium-binding proteins display some novel sprouting of processes. The results show that the mouse retina can be cultured as an explant for more than 4 weeks in a serum-free medium. This represents an important step forward because, (1) the possibility of interference of drug effects by unknown serum factors has been eliminated; and (2) the spent culture medium can be analyzed to investigate biomolecules released by the retina in vitro.


Assuntos
Técnicas de Cultura de Células/métodos , Meios de Cultura Livres de Soro/farmacologia , Proteínas do Olho , Células Fotorreceptoras Retinianas Cones/citologia , Animais , Anticorpos , Calbindina 2 , Calbindinas , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Corantes , Amarelo de Eosina-(YS) , Imunofluorescência , Expressão Gênica , Hematoxilina , Camundongos , Parvalbuminas/análise , Parvalbuminas/genética , Parvalbuminas/imunologia , RNA Mensageiro/análise , Células Fotorreceptoras Retinianas Cones/química , Células Fotorreceptoras Retinianas Cones/imunologia , Proteínas de Ligação ao Retinol/análise , Proteínas de Ligação ao Retinol/genética , Proteínas de Ligação ao Retinol/imunologia , Rodopsina/análise , Rodopsina/imunologia , Proteína G de Ligação ao Cálcio S100/análise , Proteína G de Ligação ao Cálcio S100/genética , Proteína G de Ligação ao Cálcio S100/imunologia
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