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1.
J Eur Acad Dermatol Venereol ; 34 Suppl 3: 3-11, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32557806

RESUMO

BACKGROUND: Macromolecules in skin cells are damaged when exposed to environmental stressors, leading to disrupted cellular function and homeostasis. While epidermal turnover can eliminate some of this damage, autophagy can rapidly remove these defective components. Niacinamide (Nam) is known to induce autophagy and optimizing formulations to maximize this response could provide improved homeostasis in stressed skin. OBJECTIVE: To determine (i) whether Nam can induce autophagy related 5 (ATG5), an autophagy marker, in human keratinocytes and (ii) whether optimized low pH Nam formulations can enhance the response in 3D skin models. METHODS: Human keratinocytes treated with Nam were evaluated for autophagosome accumulation and induction of ATG5 by gene expression, immunoblotting and immune-fluorescence microscopy. 3D skin equivalents were topically treated with Nam formulations at pH 5.8 and 3.8. Gene expression profiling and immunoblot analysis of ATG5 were performed. RESULTS: Nam treatment of keratinocytes led to an accumulation of autophagosomes with a maximal signal at 48 h. Gene expression of ATG5 was induced by Nam, and immunoblots stained for ATG5 showed a significant increase after 6 h of treatment. Gene expression profiling of 3D epidermal skin equivalents treated with Nam at pH 3.8 showed stronger induction of autophagy-related genes, including ATG5, compared with pH 5.8 formulas. Enrichment for gene ontology terms on autophagy showed an increased linkage with Nam formulas at pH 3.8. CONCLUSIONS: We found that Nam induces autophagosome accumulation and ATG5 levels in keratinocytes. We also discovered that a Nam formulation at pH 3.8 can further increase levels of ATG5 in 3D skin models when compared to Nam at pH 5.8. These data support that Nam can induce autophagy in keratinocytes and formulations at pH 3.8 can enhance the impact. We hypothesize that optimized formulations at pH 3.8 can improve skin ageing appearance via autophagy induction.


Assuntos
Proteína 5 Relacionada à Autofagia , Autofagia , Queratinócitos , Niacinamida , Proteína 5 Relacionada à Autofagia/genética , Expressão Gênica , Humanos , Concentração de Íons de Hidrogênio , Queratinócitos/metabolismo
2.
Int J Cosmet Sci ; 42(2): 217-219, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31955438

RESUMO

Niacinamide has been suggested to impact hair biology via stimulation of VEGF synthesis. Testing in an in vitro VEGF synthesis assay, it was found that niacinamide cannot stimulate VEGF synthesis across a broad dose-response range.


Assuntos
Cabelo/efeitos dos fármacos , Niacinamida/administração & dosagem , Administração Tópica , Relação Dose-Resposta a Droga , Cabelo/crescimento & desenvolvimento , Humanos , Niacinamida/farmacologia , Fator A de Crescimento do Endotélio Vascular/biossíntese
3.
Rev Sci Instrum ; 89(12): 124706, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30599610

RESUMO

The performance of a reversible helical electromagnetic launcher (RHEML) is reported and discussed. The results demonstrate the feasibility of using the RHEML as an electrically programmable shock tester (EPST). The data show that the reversible helical electromagnetic launcher can be operated with parallel-connected armatures that share current and force. This report is also the first-ever successful demonstration of iron-cored HEML stators. The electrical programmability of the EPST has been demonstrated by varying the shock pulse width in approximately 30 ms increments. The armature assembly has a total mass of approximately 25 kg (55 lbs). The stators are approximately 100 mm (4 in.) in diameter and 2.3 m (90 in.) long. The large mass reversible helical electromagnetic launcher is powered by a 1 MJ capacitive pulse forming network. The armature assembly has a measured minimum velocity of 0.4 m/s and a maximum velocity of 8.3 m/s. The minimum acceleration/deceleration force is 4.3 gees, while the maximum acceleration/deceleration force is 30.7 gees. The minimum shock pulse width is 16 ms, and the maximum shock pulse width is 150 ms.

4.
Sci Rep ; 7(1): 14576, 2017 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-29109440

RESUMO

The North Atlantic is characterized by diatom-dominated spring blooms that results in significant transfer of carbon to higher trophic levels and the deep ocean. These blooms are terminated by limiting silicate concentrations in summer. Numerous regional studies have demonstrated phytoplankton community shifts to lightly-silicified diatoms and non-silicifying plankton at the onset of silicate limitation. However, to understand basin-scale patterns in ecosystem and climate dynamics, nutrient inventories must be examined over sufficient temporal and spatial scales. Here we show, from a new comprehensive compilation of data from the subpolar Atlantic Ocean, clear evidence of a marked pre-bloom silicate decline of 1.5-2 µM throughout the winter mixed layer during the last 25 years. This silicate decrease is primarily attributed to natural multi-decadal variability through decreased winter convection depths since the mid-1990s, a weakening and retraction of the subpolar gyre and an associated increased influence of nutrient-poor water of subtropical origin. Reduced Arctic silicate import and the projected hemispheric-scale climate change-induced weakening of vertical mixing may have acted to amplify the recent decline. These marked fluctuations in pre-bloom silicate inventories will likely have important consequences for the spatial and temporal extent of diatom blooms, thus impacting ecosystem productivity and ocean-atmosphere climate dynamics.

5.
J Anim Sci ; 95(9): 4139-4149, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28991996

RESUMO

A 2 × 2 factorial assessed the effect of trace mineral (TM) sources fed within low- or high-S diets on the mineral status and performance of cattle. Angus crossbred steers ( = 48; 6/pen) were blocked by BW (316 ± 16.6 kg), assigned to low-S (0.27%; LS) or high-S (0.54%; HS; added as CaSO) diets, and supplemented TM at 10 mg Cu, 30 mg Zn, and 20 mg Mn/kg DM from hydroxy (HYD; IntelliBond; Micronutrients USA LLC, Indianapolis, IN) or inorganic (sulfates; ING) sources ( = 12 steers/treatment). Steers were fed corn silage and corn-based diets via GrowSafe bunks in the growing period (GP; 84 d) and finishing period (FP; 77 d), respectively. Plasma and liver were collected at trial initiation and end of GP and FP for mineral concentrations. End of GP and FP red blood cell lysate superoxide dismutase (SOD) and Mn-SOD activity and liver glutathione concentrations were measured. Data were used as a 2 × 2 factorial using Proc Mixed of SAS (SAS Inst. Inc., Cary, NC) with initial plasma and liver status analyzed as covariates. High S decreased ( < 0.01) liver Cu and tended ( ≤ 0.10) to decrease plasma Cu concentrations. Liver Cu concentrations were lower in HYD than ING in the FP ( < 0.01). High S decreased ( = 0.04) GP plasma Zn concentrations and tended to decrease ( = 0.10) GP liver Zn. There were GP ( = 0.05) and FP ( = 0.02) S × TM effects for liver Mn concentrations where GP LS-HYD was greater than all other treatments, whereas FP LS-HYD was lower than HS-HYD and LS-ING and FP HS-ING was less than LS-ING. Glutathione, SOD, and Mn-SOD were not different ( ≥ 0.13) in the GP, but S × TM tended to affect FP Mn-SOD ( = 0.10), where LS-HYD tended to be lower than LS-ING. Oxidized glutathione in FP tended to be lower ( = 0.06) for HYD than ING. In the GP, there were S × TM effects on performance where LS-HYD had greater ADG and G:F ( ≤ 0.05) than HS-HYD, whereas LS and HS-ING were intermediate. For FP performance S × TM effects were noted where LS-HYD and HS-ING tended ( = 0.10) to gain more than HS-HYD and HS-HYD had lower G:F ( = 0.04) than HS-ING. There were no effects of S × TM on final BW, DMI, or ADG ( ≥ 0.11); however, HS-HYD had lower G:F than other treatments overall ( = 0.05). High S decreased back fat and yield grade ( = 0.03), and rib eye area was smaller for HYD than ING ( = 0.02). In this study HS decreased markers of Cu and Zn status, and differential effects of HYD vs. ING minerals were noted across dietary phases, although all steers maintained adequate TM status.


Assuntos
Bovinos/fisiologia , Suplementos Nutricionais , Minerais/sangue , Oligoelementos/farmacologia , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta/veterinária , Glutationa/análise , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Silagem , Enxofre/metabolismo , Superóxido Dismutase/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Zea mays
8.
Pediatr Hematol Oncol ; 31(5): 425-34, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24383443

RESUMO

Transfusions of granulocytes can be used as an adjunct therapy to antimicrobials in patients with infection and neutropenia or granulocyte dysfunction. However, there is a lack of strong clinical evidence to support the use of this treatment strategy, particularly in children. We retrospectively reviewed the medical records of children who received granulocytes at our institution from April 2009 to October 2012, with emphasis on primary indication for the transfusion and clinical outcome in terms of infection. The patients had granulocyte dysfunction or severe neutropenia, defined as absolute neutrophil count (ANC) < 500 cells/mm(3) due to chemotherapy or hematopoietic stem cell transplant (HSCT), and reasonable hope for bone marrow recovery or engraftment. Eighteen children received granulocytes during 20 distinct episodes: 62% (n = 13) for acute infection, 29% (n = 5) for unresolved chronic infection during the time of HSCT, and 9% (n = 2) for other clinical conditions such as typhilitis and appendectomy. Overall, 92% (n = 12) of the episodes of acute infection had complete or partial resolution, as determined by review of vital signs, physical exam findings and discontinuation of antimicrobials. A substantial number (46%) of children who received granulocytes for acute infection developed respiratory adverse events, but all of these recovered. We conclude that granulocyte transfusions continue to be primarily used in neutropenic patients with acute infections, and that its use in this group of patients is reasonable. However, a prospective randomized clinical trial is needed to evaluate safety and whether the use of granulocytes is superior to antimicrobial-only therapy.


Assuntos
Granulócitos , Infecções/terapia , Transfusão de Leucócitos , Neutropenia/terapia , Doença Aguda , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Infecções/sangue , Infecções/etiologia , Contagem de Leucócitos , Masculino , Neutropenia/sangue , Neutropenia/etiologia , Estudos Retrospectivos
9.
Blood Cancer J ; 3: e167, 2013 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-24317089

RESUMO

Multiple myeloma is characterized by the production of substantial quantities of monoclonal protein. We have previously demonstrated that select inhibitors of the isoprenoid biosynthetic pathway (IBP) induce apoptosis of myeloma cells via inhibition of Rab geranylgeranylation, leading to disruption of monoclonal protein trafficking and induction of the unfolded protein response (UPR) pathway. Heat-shock protein 90 (HSP90) inhibitors disrupt protein folding and are currently under clinical investigation in myeloma. The effects of combining IBP and HSP90 inhibitors on cell death, monoclonal protein trafficking, the UPR and chaperone regulation were investigated in monoclonal protein-producing cells. An enhanced induction of cell death was observed following treatment with IBP and HSP90 inhibitors, which occurred through both ER stress and non-ER stress pathways. The HSP90 inhibitor 17-AAG abrogated the effects of the IBP inhibitors on intracellular monoclonal protein levels and localization as well as induction of the UPR in myeloma cells. Disparate effects on chaperone expression were observed in myeloma vs amyloid light chain cells. Here we demonstrate that the novel strategy of targeting MP trafficking in concert with HSP90 enhances myeloma cell death via a complex modulation of ER stress, UPR, and cell death pathways.

12.
Accid Anal Prev ; 41(5): 1034-9, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19664442

RESUMO

In an effort to improve pedestrian safety, several states in the United States changed their pedestrian laws by changing the requirement that drivers yield to pedestrians in crosswalks to a requirement that drivers stop for pedestrians in crosswalks. This study examined whether this change had an effect on pedestrian safety in the United States, with its focus on low-speed roads. To examine the association between changes in pedestrian laws and changes in pedestrian-involved fatal crashes, three approaches were employed: before-after analysis, time-series analysis, and cross-sectional analysis. Pedestrian-involved fatal traffic crashes on low-speed roads were extracted from the U.S. national fatal crash database, the Fatality Analysis Reporting System (FARS), from 1980 through 2005. This study found no statistically significant reduction in pedestrian-involved fatal crashes attributable to changes in the laws, yet this finding is not definitive because of study limitations such as the omission of relevant exposure data.


Assuntos
Acidentes de Trânsito/estatística & dados numéricos , Condução de Veículo/estatística & dados numéricos , Automóveis/estatística & dados numéricos , Segurança/estatística & dados numéricos , Caminhada/fisiologia , Análise de Variância , Estudos Transversais , Bases de Dados Factuais , Georgia , Humanos , Maryland , Minnesota , Nebraska , Oregon , Análise de Regressão , Estatística como Assunto , Fatores de Tempo , Estados Unidos , Washington
13.
Poult Sci ; 85(10): 1791-4, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17012170

RESUMO

Plasma uric acid (PUA) is a consensus physiological biomarker for many phenotypes in vertebrates because it is a reliable indicator for processes such as oxidative stress and tubular function. In birds, it is considered a major antioxidant and is also the primary endproduct of nitrogen metabolism. Despite this importance, knowledge of baseline levels of PUA in physiologically normal birds, including the turkey, Meleagris gallopavo, is limited. Here, we compared PUA levels in a total of 106 apparently normal male and female birds at 8 and 32 wk of age from 5 strains of the domestic turkey, including Bourbon Red, Narragansett, Blue Slate, Royal Palm, and Spanish Black. Though differences in PUA were not significant at 8 and 32 wk of age, BW, variety, and sex effects were highly significant. When adjusted for BW, female birds had, on average, a higher PUA per kilogram of BW than male birds. When adjusted for both sex and BW, Royal Palm birds had the lowest average PUA, and Blue Slate had the highest PUA. Results of these investigations represent the first comparative analysis of PUA in physiologically normal turkey varieties. They suggest that differences in basal plasma levels of uric acid in physiologically normal turkeys are influenced by sex, weight, and genetic background but may be independent of age.


Assuntos
Perus/sangue , Perus/classificação , Ácido Úrico/sangue , Envelhecimento , Animais , Feminino , Masculino , Perus/crescimento & desenvolvimento
15.
Pediatr Pulmonol ; 34(5): 395-7, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12357488

RESUMO

A 9-year-old boy developed significant hemoptysis and pulmonary parenchymal injury following blunt trauma. There was delayed development of hemoptysis following chest injury, and the trauma did not produce any evidence of external body injury.


Assuntos
Hemoptise/etiologia , Lesão Pulmonar , Ferimentos não Penetrantes/complicações , Criança , Hemoptise/diagnóstico por imagem , Humanos , Pulmão/diagnóstico por imagem , Pulmão/patologia , Masculino , Radiografia , Fatores de Tempo , Ferimentos não Penetrantes/diagnóstico por imagem
16.
Phys Rev Lett ; 88(1): 012502, 2002 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-11800940

RESUMO

The quality and intensity of gamma rays at the High Intensity gamma-ray Source are shown to make nuclear resonance fluorescence studies possible at a new level of precision and efficiency. First experiments have been carried out using an intense (10(7) gamma/s) beam of 100% linearly polarized, nearly monoenergetic, gamma rays on the semimagic nucleus (138)Ba. Negative parity quantum numbers have been assigned to 18 dipole excitations of (138)Ba between 5.5 MeV and 6.5 MeV from azimuthal gamma-intensity asymmetries.

17.
Cell Growth Differ ; 12(10): 487-96, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11682460

RESUMO

The cellular responses to carcinogen exposure influence cellular fate, which in turn modulates the neoplastic response. Certain hexavalent chromium [Cr(VI)] compounds are implicated as occupational respiratory carcinogens at doses that are both genotoxic and cytotoxic. We examined the mechanism of Cr(VI)-induced apoptosis in normal human fibroblasts (BJ) immortalized by human telomerase gene transfection (BJ-hTERT), and we assessed the spectrum of cumulative cellular fates [(a) regaining of replicative potential; (b) terminal growth arrest; or (c) apoptosis] for a narrow range of increasingly genotoxic doses of Cr(VI). Exposure of BJ-hTERT cells to Cr(VI) resulted in a dose-dependent increase in apoptosis that involved mitochondrial disruption as evidenced by mitochondrial membrane depolarization and cytochrome c release. The initial response to Cr(VI) exposure was inhibition of cell cycle progression. At the lowest dose tested (1 microM; 32% clonogenic survival), the cell cycle inhibition led to terminal growth arrest but no apoptosis. The fraction of terminally growth arrested cells increased as the dose was increased to 3 microM but then decreased at 4, 5, and 6 microM as apoptosis became the predominant cell fate. Our results suggest that cell populations exposed to Cr(VI) have a different spectrum of responses, depending on the extent of DNA damage, and that the regaining of replicative potential after relatively higher genotoxic exposures may be attributable to either escape from, or resistance to, terminal growth arrest or apoptosis.


Assuntos
Apoptose , Cromatos/farmacologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/patologia , Compostos de Sódio/farmacologia , Telomerase/metabolismo , Caspase 3 , Caspases/metabolismo , Ciclo Celular , Divisão Celular/efeitos dos fármacos , Linhagem da Célula , Células Cultivadas , Proteínas de Ligação a DNA , Relação Dose-Resposta a Droga , Humanos , Imuno-Histoquímica , Membranas Intracelulares , Microscopia de Fluorescência , Mitocôndrias/metabolismo , Fenótipo , Estresse Fisiológico , Telomerase/genética , Fatores de Tempo , Transfecção
18.
J Am Osteopath Assoc ; 101(6): 347-9, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11432085

RESUMO

The authors evaluated construct validity of scores for the Comprehensive Osteopathic Medical Licensing Examination (COMLEX-USA), the examination used to evaluate osteopathic physicians for licensure. They computed correlations between students' grades in the first 2 years of osteopathic medical school and their scores on the COMPLEX-USA Level 1 (N = 187) and Level 2 (N = 86), as well as correlations between third- and fourth-year clerkship grades and the COMLEX-USA Level 2. Correlations of Level 1 scores with grades for years one, two, and the first 2 years combined were .74, .80, and .81, respectively; for Level 2, correlations were .59, .70, and .71. Correlation between clerkship grades and scores for the COMLEX-USA Level 2 was .26. The strong correlation between COMLEX-USA results and grades for the didactic curriculum in the first 2 years of medical school provides evidence for the construct validity of scores for the COMLEX-USA Levels 1 and 2.


Assuntos
Educação de Graduação em Medicina/normas , Avaliação Educacional , Licenciamento em Medicina/normas , Medicina Osteopática/educação , Medicina Osteopática/legislação & jurisprudência , Adulto , Feminino , Humanos , Masculino , Sensibilidade e Especificidade , Estados Unidos
19.
Mol Vis ; 7: 95-100, 2001 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-11320353

RESUMO

PURPOSE: To determine the protein and transcript levels for rhodopsin (Rh1), arrestin 1 (Arr1), and arrestin 2 (Arr2) over a 12 h light/12 h dark cycle in the retina of the fruit fly, Drosophila melanogaster. This information is important for understanding the process of photoreceptor membrane turnover. METHODS: Drosophila were entrained for several generations to a daily 12 h light/12 h dark cycle. They were sacrificed at 4 h intervals, beginning at the time of onset of the light phase. Proteins were resolved by polyacrylamide gel electrophoresis (PAGE) and subjected to immunoblot analysis using antibodies directed to rhodopsin, NinaA, Arr1, and Arr2. Northern blots were incubated with riboprobes corresponding to the rhodopsin gene (ninaE), arrestin1 (arr1), and arrestin2 (arr2). RESULTS: In entrained Drosophila, protein and mRNA levels for rhodopsin, arrestin1, and arrestin2 were constant during a 12 h light/12 h dark cycle. CONCLUSIONS: These results indicate that rhodopsin and arrestin protein synthesis in Drosophila photoreceptors do not fluctuate on a daily cycle. These findings are similar to those obtained in Xenopus laevis, but in contrast to a variety of other vertebrate and invertebrate species.


Assuntos
Arrestinas/genética , Ritmo Circadiano/fisiologia , Proteínas de Drosophila , Drosophila melanogaster/genética , Fosfoproteínas/genética , Células Fotorreceptoras de Invertebrados/metabolismo , RNA Mensageiro/metabolismo , Rodopsina/genética , Animais , Animais Geneticamente Modificados , Arrestinas/metabolismo , Northern Blotting , Sondas de DNA , Drosophila melanogaster/metabolismo , Eletroforese em Gel de Poliacrilamida , Proteínas do Olho/genética , Proteínas do Olho/metabolismo , Expressão Gênica , Immunoblotting , Fosfoproteínas/metabolismo , Rodopsina/metabolismo
20.
J Psychosom Res ; 48(6): 547-54, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11033373

RESUMO

OBJECTIVES: Individuals with chronic fatigue and chronic fatigue syndrome (CFS) face debilitating symptoms as well as stressful life situations that may result from their condition. The goal of this study was to examine the coping strategies used by fatigue-discordant twin pairs. METHODS: We utilized a co-twin design to assess how twin pairs discordant for chronic fatigue and CFS cope with stress. All twin pairs were administered the Revised Ways of Coping Checklist. RESULTS: Overall, the pattern of coping strategies was similar for fatigued and non-fatigued twins. However, twins with chronic fatigue or CFS utilized more avoidance strategies than their non-fatigued counterparts; those with chronic fatigue also used more avoidance relative to problem-focused coping than their co-twins. CONCLUSIONS: These results suggest that while fatigue-discordant twins generally exhibit similar behavior patterns in order to cope with stress, there may be an association between fatigue and avoidance coping. Future research should focus on the role of avoidance and its relationship to fatiguing illnesses.


Assuntos
Adaptação Psicológica , Doenças em Gêmeos , Síndrome de Fadiga Crônica/psicologia , Adulto , Mecanismos de Defesa , Feminino , Humanos , Masculino , Inventário de Personalidade , Resolução de Problemas , Estresse Psicológico/complicações , Gêmeos Dizigóticos/psicologia , Gêmeos Monozigóticos/psicologia
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