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1.
Br Poult Sci ; 63(2): 211-217, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34309442

RESUMO

1. Mineral excretion is an issue in the poultry industry. The use of micro minerals in nano form can increase bioavailability and decrease excretion rate. However, information concerning the bioavailability of nano manganese (Mn) in broiler chicks is limited.2. This experiment studied the influences of hot-melt extrusion (HME)-processed manganese sulphate on body weight gain, Mn bioavailability, nutrient digestibility and meat quality in broiler chicks fed a corn-soybean meal-based diet as a starter and grower phase. A total of 700 birds (Ross 308, 1-day-old) were randomly placed in 35 cages (20 birds per cage). The broiler chicks were fed one of seven experimental diets, which consisted of a control (without supplemental Mn), different levels of MnSO4 (IN-Mn60; 60, 120, and 200 mg/kg), or HME MnSO4 (HME-Mn; 60, 120, and 200 mg/kg).3. There was an increased serum Mn content in broilers fed diet supplemented with HME-Mn. In the grower phase, increased dietary Mn levels elevated the concentrations in the serum, liver, and tibia. There were increases in the excreta Mn content of broilers fed increasing levels. The supplementation of HME-Mn showed a lower percentage of abdominal fat compared with the IN-Mn treatment diets. Supplementation with HME-Mn decreased intramuscular fat compared with the diets supplemented with IN-Mn. The supplementation of HME-Mn decreased the thiobarbituric acid reactive substances (TBARS) at d 6 of age. The HME-Mn source showed a greater decrease in TBARS compared with the IN-Mn treatment.4. In conclusion, HME processing increased bioavailability and could be used as an environmentally friendly method to facilitate lower levels of Mn in the diet of broiler chickens.


Assuntos
Galinhas , Manganês , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Disponibilidade Biológica , Dieta/veterinária , Suplementos Nutricionais , Carne
2.
Clin Radiol ; 74(8): 651.e1-651.e6, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31202566

RESUMO

AIM: To investigate whether the use of metformin during computed tomography (CT) with radiocontrast agents increases the risk of contrast-induced nephropathy (CIN) and metabolic acidosis after CT in type 2 diabetes patients with mild to moderate renal failure. MATERIALS AND METHODS: Patient records from January 2015 to December 2017 were reviewed retrospectively. A total of 374 patients were included in the final analysis. Of them, 157 patients received metformin, and 217 patients were taking other oral hypoglycaemic agents (OHAs) during radiocontrast administration. RESULTS: No significant difference in CIN incidence was observed between the metformin use group and the other OHAs group (p=0.085). Metabolic acidosis after CT was seen in 91 (58%) patients who used metformin and 141 (65%) patients who were taking other OHAs. There was no relationship between metabolic acidosis after CT and the use of metformin (p=0.195). Metabolic acidosis after radiocontrast agent exposure was associated with malignant disease, low serum albumin level, and low serum total CO2 level at baseline. CONCLUSION: These data show that other factors, but not metformin use, are associated with metabolic acidosis after radiocontrast agent exposure in patients with reduced renal function. These data support current recommendations that there is no need to discontinue metformin before CT using radiocontrast agents in patients with mild to moderate renal failure.


Assuntos
Acidose/induzido quimicamente , Meios de Contraste/efeitos adversos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/efeitos adversos , Metformina/efeitos adversos , Insuficiência Renal/induzido quimicamente , Administração Oral , Idoso , Feminino , Humanos , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/uso terapêutico , Incidência , Masculino , Metformina/administração & dosagem , Metformina/uso terapêutico , Intensificação de Imagem Radiográfica/métodos , Tomografia Computadorizada por Raios X/métodos
3.
Opt Lett ; 43(7): 1610, 2018 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-29601042

RESUMO

In this erratum the funding section of Opt. Lett.42, 215 (2017)OPLEDP0146-959210.1364/OL.42.000215 has been updated.

4.
Opt Lett ; 42(2): 215-218, 2017 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-28081077

RESUMO

We demonstrate laser-driven acceleration of electrons to MeV-scale energies at 1 kHz repetition rate using <10 mJ pulses focused on near-critical density He and H2 gas jets. Using the H2 gas jet, electron acceleration to ∼0.5 MeV in ∼10 fC bunches was observed with laser pulse energy as low as 1.3 mJ. Increasing the pulse energy to 10 mJ, we measure ∼1 pC charge bunches with >1 MeV energy for both He and H2 gas jets.

5.
Biomarkers ; 22(3-4): 326-330, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27881022

RESUMO

CONTEXT: YKL-40 is an inflammatory biomarker for endothelial dysfunction that may have a role in Kawasaki disease (KD). OBJECTIVES: We investigated the association of serum YKL-40 levels with KD and established laboratory parameters for YKL-40 levels and other inflammatory markers. METHODS: YKL-40 levels and other inflammatory markers of 23 KD patients, 9 disease control patients and 11 age-matched healthy controls. RESULTS: YKL-40 concentration in the serum of KD patients significantly increased during the acute disease phase compared with those of disease controls and healthy controls. CONCLUSIONS: Increased YKL-40 levels may provide a useful inflammatory marker for patients with KD.


Assuntos
Proteína 1 Semelhante à Quitinase-3/sangue , Síndrome de Linfonodos Mucocutâneos/patologia , Doença Aguda , Biomarcadores/sangue , Estudos de Casos e Controles , Humanos , Inflamação/sangue , Síndrome de Linfonodos Mucocutâneos/sangue
6.
Oral Dis ; 23(1): 91-96, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27588367

RESUMO

PURPOSE: We aimed to identify a combined prognostic factor for predicting better performance in risk stratification. MATERIALS AND METHODS: We reviewed the clinical and pathological variables of 316 patients with oral squamous cell carcinoma (OSCC) who underwent surgery. To identify a combined predictor, principal component analysis (PCA) was performed. RESULTS: Univariate analysis showed that the independent prognostic variables for overall survival (OS) were pathologic T stage (T1 vs T4, HR = 1.99, 95% CI: = 1.083-3.675, P = 0.026) and pathologic N stage (N0 vs N2, HR=1.90, 95% CI: = 1.17-3.08, P = 0.008). In the multivariate analysis, only pathologic T stage was significant (P = 0.006 and P = 0.007); however, the multivariate model was not significant (P = 0.191). The multivariate model became significant by including lymph node ratio (LNR) instead of pathologic N stage (P = 0.0025 in numeric LNR, P = 0.0007 in categorized LNR). Also, the performance of prediction model was improved by a combined prognostic factor (P = 0.0002). CONCLUSIONS: The newly identified combined prognostic factor included resection margin, differentiation, and LNR, and they were insignificant factors independently except for LNR. This combined prognostic factor showed a good performance although it did not include molecular markers; therefore, it may be used conveniently for risk stratification of patients with OSCC by combining only clinical information.


Assuntos
Carcinoma de Células Escamosas/diagnóstico , Neoplasias Bucais/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/mortalidade , Neoplasias Bucais/patologia , Neoplasias Bucais/cirurgia , Estadiamento de Neoplasias , Análise de Componente Principal , Prognóstico , Estudos Retrospectivos , Medição de Risco/métodos , Análise de Sobrevida , Adulto Jovem
7.
Genet Mol Res ; 16(2)2017 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-28407192

RESUMO

The Japanese oak silkmoth, Antheraea yamamai Guérin-Méneville, 1861 (Lepidoptera: Saturniidae), is an important natural resource of industrial value for silk fiber production. Owing to a lack of geographic and population genetic information, systematic domestication of An. yamamai has not been possible yet. In this study, 10 microsatellite markers developed using next-generation sequencing and two mitochondrial DNA (mtDNA) gene sequences (COI and ND4) were used to investigate the genetic variation and geographic structure of An. yamamai populations in South Korea. The two mtDNA gene sequences revealed very low total genetic variation and, consequently, low geographic variation, validating the use of more variable molecular markers. Genotyping of 76 An. yamamai individuals from nine localities in South Korea showed that the observed number of alleles at each locus ranged from 3 to 26, the polymorphism information content was 0.2990-0.9014, the observed and expected heterozygosities were 0.3252-0.9076 and 0.2500-0.9054, respectively, and FIS was -0.654-0.520. The population-based FIS, FST, RST, and global Mantel tests all suggested that the An. yamamai populations were overall well-interconnected, suggesting that any population can be used as a genetic source for domestication. Nevertheless, STRUCTURE analyses using microsatellite data and mtDNA sequences indicated the presence of two genetic pools in many populations, although a plausible explanation for this observation requires further studies.


Assuntos
Bombyx/genética , DNA Mitocondrial/genética , Repetições de Microssatélites , Polimorfismo Genético , Animais , Pool Gênico
8.
Clin Exp Allergy ; 46(11): 1398-1406, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27238356

RESUMO

BACKGROUND: Younger maternal age at birth is associated with increased risk of asthma in offspring in European descent populations, but has not been studied in Latino populations. OBJECTIVES: We sought to examine the relationship between maternal age at birth and prevalence of asthma in a nationwide study of Latino children. METHODS: We included 3473 Latino children aged 8-21 years (1696 subjects with physician-diagnosed asthma and 1777 healthy controls) from five US centres and Puerto Rico recruited from July 2008 through November 2011. We used multiple logistic regression models to examine the effect of maternal age at birth on asthma in offspring overall and in analyses stratified by ethnic subgroup (Mexican American, Puerto Rican and other Latino). Secondary analyses evaluated the effects of siblings, acculturation and income on this relationship. RESULTS: Maternal age < 20 years was significantly associated with decreased odds of asthma in offspring, independent of other risk factors (OR = 0.73, 95% CI: 0.57-0.93). In subgroup analyses, the protective effect of younger maternal age was observed only in Mexican Americans (OR = 0.53, 95% CI: 0.36, 0.79). In Puerto Ricans, older maternal age was associated with decreased odds of asthma (OR = 0.65, 95% CI: 0.44-0.97). In further stratified models, the protective effect of younger maternal age in Mexican Americans was seen only in children without older siblings (OR = 0.44, 95% CI: 0.23-0.81). CONCLUSION AND CLINICAL RELEVANCE: In contrast to European descent populations, younger maternal age was associated with decreased odds of asthma in offspring in Mexican American women. Asthma is common in urban minority populations but the factors underlying the varying prevalence among different Latino ethnicities in the United States is not well understood. Maternal age represents one factor that may help to explain this variability.


Assuntos
Asma/epidemiologia , Asma/etiologia , Hispânico ou Latino , Idade Materna , Adolescente , Estudos de Casos e Controles , Criança , Feminino , Hispânico ou Latino/estatística & dados numéricos , Humanos , Masculino , Vigilância da População , Fatores de Risco , Estados Unidos/epidemiologia , Adulto Jovem
9.
Clin Radiol ; 71(6): 532-6, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27063815

RESUMO

AIM: To evaluate the changes in serum creatinine and total CO2 levels in patients receiving metformin during administration of contrast medium. MATERIALS AND METHODS: Patient records from January 2012 to December 2012 after the administration of contrast medium were reviewed retrospectively. A total of 924 patients were included for the final analysis. Of them, 105 received metformin during contrast medium administration, 112 were taking other oral hypoglycaemic agents, and 707 patients were not diabetic (controls). RESULTS: No significant change in total CO2 levels was detected (p=0.678). Metabolic acidosis was present in 33 (31.4%) metformin users, 31 (28.6%) other oral hypoglycaemic agent users, and 153 (21.6%) control patients. In the present logistic regression analysis, age, baseline levels of creatinine, and total CO2 levels were associated with metabolic acidosis after contrast medium exposure. CONCLUSION: These data indicate the presence of a coexisting risk factor, other than metformin use, associated with metabolic acidosis after contrast medium exposure. No relationship was found between the use of metformin and metabolic acidosis during contrast medium exposure.


Assuntos
Acidose/epidemiologia , Dióxido de Carbono/sangue , Meios de Contraste/administração & dosagem , Creatinina/sangue , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Nefropatias/epidemiologia , Metformina/administração & dosagem , Acidose/sangue , Acidose/induzido quimicamente , Acidose/diagnóstico , Administração Oral , Idoso , Comorbidade , Meios de Contraste/efeitos adversos , Relação Dose-Resposta a Droga , Interações Medicamentosas , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/sangue , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/diagnóstico , Feminino , Humanos , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/efeitos adversos , Nefropatias/sangue , Nefropatias/diagnóstico , Masculino , Metformina/efeitos adversos , Pessoa de Meia-Idade , Prevalência , República da Coreia/epidemiologia , Fatores de Risco
10.
Genet Mol Res ; 15(3)2016 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-27706685

RESUMO

The slender shiner Pseudopungtungia tenuicorpa (Cypriniformes; Cyprinidae; Gobioninae) is an endangered freshwater fish species endemic to Korea. The current strategies for its conservation involve the study of population genetic characters and identification of management units. These strategies require suitable molecular markers to study genetic diversity and genetic structure. Here, we developed nine polymorphic microsatellite markers for P. tenuicorpa for the first time by applying an enrichment method from a size-selected genomic library. The developed microsatellite markers produced a total of 101 alleles (average 11.2). The observed and expected heterozygosities averaged 0.805 and 0.835, respectively. Among the nine identified markers, five markers showed successful amplification across five related Korean Gobioninae species. Thus, the microsatellite markers developed in this study will be useful to establish conservation strategies for both P. tenuicorpa and other related species.


Assuntos
Cyprinidae/genética , Genética Populacional , Repetições de Microssatélites , Alelos , Animais , Conservação dos Recursos Naturais , Cyprinidae/classificação , Espécies em Perigo de Extinção , Genoma , Biblioteca Genômica , Heterozigoto , Reação em Cadeia da Polimerase , República da Coreia , Especificidade da Espécie
12.
Clin Exp Immunol ; 177(1): 203-11, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24635044

RESUMO

The major goals of Kawasaki disease (KD) therapy are to reduce inflammation and prevent thrombosis in the coronary arteries (CA), but some children do not respond to currently available non-specific therapies. New treatments have been difficult to develop because the molecular pathogenesis is unknown. In order to identify dysregulated gene expression in KD CA, we performed high-throughput RNA sequencing on KD and control CA, validated potentially dysregulated genes by real-time reverse transcription-polymerase chain reaction (RT-PCR) and localized protein expression by immunohistochemistry. Signalling lymphocyte activation molecule CD84 was up-regulated 16-fold (P < 0·01) in acute KD CA (within 2 months of onset) and 32-fold (P < 0·01) in chronic CA (5 months to years after onset). CD84 was localized to inflammatory cells in KD tissues. Genes associated with cellular proliferation, motility and survival were also up-regulated in KD CA, and immune activation molecules MX2 and SP140 were up-regulated in chronic KD. CD84, which facilitates immune responses and stabilizes platelet aggregates, is markedly up-regulated in KD CA in patients with acute and chronic arterial disease. We provide the first molecular evidence of dysregulated inflammatory responses persisting for months to years in CA significantly damaged by KD.


Assuntos
Antígenos CD/metabolismo , Antígenos Nucleares/metabolismo , Plaquetas/imunologia , Síndrome de Linfonodos Mucocutâneos/imunologia , Proteínas de Resistência a Myxovirus/metabolismo , Fatores de Transcrição/metabolismo , Calcificação Vascular/imunologia , Doença Aguda , Antígenos CD/genética , Antígenos Nucleares/genética , Processos de Crescimento Celular/genética , Movimento Celular/genética , Sobrevivência Celular/genética , Doença Crônica , Vasos Coronários/patologia , Feminino , Ensaios de Triagem em Larga Escala , Humanos , Lactente , Masculino , Síndrome de Linfonodos Mucocutâneos/sangue , Síndrome de Linfonodos Mucocutâneos/genética , Proteínas de Resistência a Myxovirus/genética , Agregação Plaquetária/genética , RNA Mensageiro/análise , Família de Moléculas de Sinalização da Ativação Linfocitária , Fatores de Transcrição/genética , Regulação para Cima , Calcificação Vascular/sangue , Calcificação Vascular/genética
13.
Genes Immun ; 14(6): 401-6, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23719032

RESUMO

Mechanism of thymic compartmentalization was studied in the transgenic system using the promoter of thymic stromal cotransporter (TSCOT), a cortical thymic epithelium-specific gene. The transgenic 3.1 kb TSCOT (3.1T) and 4.4 kb TSCOT (4.4T) promoters recapitulated the thymic organ and the cortical epithelial cell-specific expression at the newborn stage. However, the 3.1T driving enhanced green fluorescent protein (EGFP; 3.1T-EGFP) or Cre-recombinase (3.1T-CreE) redistributed the expression into the medulla at the adult stages. Two Cre-transgenic lines (3.1T-CreE and 4.4T-CreE), when crossed with the ROSA LacZ or EGFP lines, showed the reporter expression in both the cortex and the medulla. TSCOT promoter activities were also verified in the transient thymic epithelial cell (TEC) population expressing keratin 5 and keratin 8. These indicate that the TSCOT promoter is turned on in the bipotent TEC precursors and regulated in a compartment-specific, developmentally regulated fashion. These transgenic lines provide the useful systems for delineating the specific pathways for TEC lineage development and function.


Assuntos
Linhagem da Célula , Células Epiteliais/metabolismo , Células-Tronco Pluripotentes/metabolismo , Regiões Promotoras Genéticas , Simportadores/genética , Timo/metabolismo , Animais , Diferenciação Celular , Células Epiteliais/citologia , Regulação da Expressão Gênica no Desenvolvimento , Queratinas/genética , Queratinas/metabolismo , Camundongos , Células-Tronco Pluripotentes/citologia , Simportadores/metabolismo , Timo/citologia , Timo/crescimento & desenvolvimento , Transcrição Gênica
14.
Int J Immunogenet ; 40(5): 356-60, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23594084

RESUMO

The human interleukin 6 receptor consists of two membrane-bound glycoproteins (IL-6Rα, IL-6RA and gp130/IL-6Rß, IL-6RB) interacting with IL-6, which is a multifunctional cytokine essential to the regulation of the immune response and acute-phase reactions. We have genotyped a single-nucleotide polymorphism (SNP) of the IL-6RA in Korean patients with systemic lupus erythematosus (SLE) (n = 300) and normal controls (NC, n = 299). Three SNPs were identified in the IL-6RA gene; -208 G ≥ A (NM_000565.3:c.-208G ≥ A, rs4845617) in the promoter region, 48841 T ≥ A (NM_000565.3:c.1067-17T ≥ A, rs4845374) in the intron 8 region and 48864 A ≥ C (NM_000565.3:c.1073A ≥ C, rs2228145) in the exon 9 region. There were no differences between the SLE and the NC in the genotype and haplotype frequencies. The 48864 A>C polymorphism was significantly associated with rash (P = 0.008). Also, the frequency of rash (P = 0.037), leucopenia (P = 0.033) and lymphopenia (P = 0.027) was significantly higher in patients with SLE having the haplotype HT2 [ATC]. These data suggest that genetic polymorphisms of IL-6RA gene may be associated with disease phenotypes of SLE in Korean.


Assuntos
Lúpus Eritematoso Sistêmico/genética , Receptores de Interleucina-6/genética , Adulto , Exantema/genética , Feminino , Frequência do Gene , Predisposição Genética para Doença , Haplótipos , Humanos , Linfopenia/genética , Masculino , Polimorfismo de Nucleotídeo Único , República da Coreia
15.
Mol Biol (Mosk) ; 47(4): 618-24, 2013.
Artigo em Russo | MEDLINE | ID: mdl-24466751

RESUMO

The upregulation of dopaminergic neuronal differentiation is necessary for stem cell therapy in Parkinson's disease (PD). In this study, neuronal differentiation efficiency increased by more than 2 times in P19 embryonic stem cells (ESCs) induced by N-acetylcysteine (NAC) and retinoic acid (RA) as compared to RA alone, with suppressed glial differentiation. The majority of NAC-treated stem cells grafted into brains of PD mice differentiated into dopaminergic neurons and persisted well for 6 weeks. Parkinsonism was also greatly improved after grafting NAC-treated cells in comparison to cells treated with only RA. Our results strongly suggest that NAC treatment may be an effective strategy for generating stem cells fated to become dopaminergic neurons for PD clinical therapy.


Assuntos
Acetilcisteína/farmacologia , Diferenciação Celular/efeitos dos fármacos , Células-Tronco Embrionárias/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Transtornos Parkinsonianos/patologia , Transtornos Parkinsonianos/terapia , Animais , Encéfalo/patologia , Células Cultivadas , Modelos Animais de Doenças , Dopamina/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Transplante de Células-Tronco , Tretinoína/farmacologia
16.
Ann Oncol ; 23(2): 361-7, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21566150

RESUMO

BACKGROUND: Nomograms are statistics-based tools that provide the overall probability of a specific outcome. In our previous study, we developed a nomogram that predicts recurrence of early gastric cancer (EGC) after curative resection. We carried out this study to externally validate our EGC nomogram. PATIENTS AND METHODS: The EGC nomogram was established from a retrospective EGC database that included 2923 consecutive patients. This nomogram was independently externally validated for a cohort of 1058 consecutive patients. For the EGC nomogram validation, we assessed both discrimination and calibration. RESULTS: Within the follow-up period (median 37 months), a total of 11 patients (1.1%) experienced recurrence. The concordance index (c-index) was 0.7 (P = 0.02) and the result of the overall C index was 0.82 [P = 0.006, 95% confidence interval (CI) 0.59-1.00]. The goodness of fit test showed that the EGC nomogram had significantly good fit for 1- and 2-year survival intervals (P = 0.998 and 0.879, respectively). The actual and predicted survival outcomes showed good agreement, suggesting that the survival predictions from the nomogram are well calibrated externally. CONCLUSIONS: A preexisting nomogram for predicting disease-free survival (DFS) of EGC after surgery was externally validated. The nomogram is useful for accurate and individual prediction of DFS, patient prognostication, counseling, and follow-up planning.


Assuntos
Adenocarcinoma/cirurgia , Recidiva Local de Neoplasia , Nomogramas , Neoplasias Gástricas/cirurgia , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Neoplasias Gástricas/patologia
17.
Opt Express ; 20(18): 19778-86, 2012 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-23037030

RESUMO

Two-dimensional (2-D) transverse photocurrent generation is studied and applied to control and optimize terahertz energy and polarization in two-color, laser-produced air filaments. A full control of terahertz output is demonstrated and explained in the context of 2-D photocurrent model.


Assuntos
Lasers , Iluminação/instrumentação , Gases em Plasma/química , Desenho Assistido por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Radiação Terahertz
18.
Phys Rev Lett ; 109(18): 183902, 2012 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-23215280

RESUMO

We observe off-axis phase-matched terahertz generation in long air-plasma filaments produced by femtosecond two-color laser focusing. Here, phase matching naturally occurs due to off-axis constructive interference between locally generated terahertz waves, and this determines the far-field terahertz radiation profiles and yields. For a filament longer than the characteristic two-color dephasing length, it emits conical terahertz radiation in the off-axis direction, peaked at 4-7° depending on the radiation frequencies. The total terahertz yield continuously increases with the filament length, well beyond the dephasing length. The phase-matching condition observed here provides a simple method for scalable terahertz generation in elongated plasmas.

19.
J Periodontal Res ; 47(6): 800-10, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22780690

RESUMO

BACKGROUND AND OBJECTIVE: Polycan is a promising candidate for the treatment of periodontal disease. This study was undertaken to examine whether Polycan, a type of ß-glucan, has a protective effect on ligature-induced experimental periodontitis and related alveolar bone loss in Sprague-Dawley rats. MATERIAL AND METHODS: Polycan was orally administered, daily, for 10 d, at 21.25, 42.5 or 85 mg/kg, beginning 1 d after ligation. Changes in body weight and alveolar bone loss were monitored, and the anti-inflammatory effects of Polycan were determined by measuring the levels of myeloperoxidase (MPO), interleukin-1beta (IL-1ß) and tumor necrosis factor-alpha (TNF-α) in gingival tissue. We also evaluated inducible nitric oxide synthase (iNOS) activity and malondialdehyde (MDA) concentrations as a measure of the antioxidant effect. RESULTS: Ligature placement led to a marked decrease in body weight, increased alveolar bone loss and increased concentrations of MPO, IL-1ß, TNF-α and MDA, as well as increased iNOS activity and inflammatory cell infiltration and decreased collagen-fiber content. Histological examination revealed increases in the number and activity of osteoclast cells, decreases in alveolar bone volume and elevated percentages of osteclasts on the alveolar bone surface. Daily oral treatment with 42.5 or 85 mg/kg of Polycan for 10 d led to significant, dose-dependent inhibition of the effect of ligature placement. CONCLUSION: Taken together, these results suggest that 10 d of oral treatment with Polycan effectively inhibits ligature placement-induced periodontitis and related alveolar bone loss via an antioxidant effect.


Assuntos
Perda do Osso Alveolar/prevenção & controle , Antioxidantes/uso terapêutico , Periodontite/tratamento farmacológico , beta-Glucanas/uso terapêutico , Animais , Antioxidantes/farmacologia , Peso Corporal/efeitos dos fármacos , Gengiva/metabolismo , Interleucina-1beta/análise , Peroxidação de Lipídeos , Masculino , Malondialdeído/análise , Óxido Nítrico Sintase Tipo II/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Peroxidase/metabolismo , Ratos , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/análise , beta-Glucanas/farmacologia
20.
Phys Chem Chem Phys ; 14(13): 4365-73, 2012 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-22270868

RESUMO

Microporous materials have a great importance in catalysis, delivery, storage and separation in terms of their performance and efficiency. Most microporous materials are comprised of inorganic frameworks, while thermally rearranged (TR) polymers are a microporous organic polymer which is tuned to optimize the cavity sizes and distribution for difficult separation applications. The sub-nano sized microcavities are controlled by in situ thermal treatment conditions which have been investigated by positron annihilation lifetime spectroscopy (PALS). The size and relative number of cavities increased from room temperature to 230 °C resulting in improvements in both permeabilities and selectivities for H(2)/CO(2) separation due to the significant increase of gas diffusion and decrease of CO(2) solubility. The highest performance of the well-tuned TR-polymer membrane was 206 Barrer for H(2) permeability and 6.2 of H(2)/CO(2) selectivity, exceeding the polymeric upper bound for gas separation membranes.


Assuntos
Dióxido de Carbono/química , Membranas Artificiais , Polímeros/química , Temperatura , Hidrogênio/química , Tamanho da Partícula , Polímeros/síntese química , Porosidade , Propriedades de Superfície
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