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1.
J Chem Phys ; 156(21): 214501, 2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35676139

RESUMO

Soret effect and diffusion in triethylene glycol (TEG)-water mixtures were investigated as a function of concentration at 25 °C by means of optical digital interferometry, with the use of a classical Soret cell. Diffusion D, thermal diffusion DT, and Soret ST coefficients are described for the full concentration range and an analysis is made individually for TEG-water mixture and within a series of n-ethylene glycol (n-EG) aqueous systems. All coefficients decrease with increasing the concentration of TEG and n-EG. ST shows a change of sign with concentration, and this change is directly related to the ability of the n-EG molecule to establish hydrogen bonding with water. Diffusion and thermal diffusion coefficients present a plateau behavior with increasing concentration, showing the occurrence of changes in the preferential interactions in aqueous solution with concentration and meaning that, at high TEG composition, ether oxygens can be involved in the molecular interactions.


Assuntos
Etilenoglicol , Água , Difusão , Polietilenoglicóis
2.
Arq. bras. med. vet. zootec. (Online) ; 72(1): 233-242, Jan.-Feb. 2020. tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-1088935

RESUMO

O objetivo do presente estudo foi avaliar o desempenho zootécnico, os parâmetrosmorfométricos, o comportamento social, a viabilidade econômica e a análise microbiológica da água de cultivo e de tecidos corpóreos de Betta splendens alimentados com folha da amendoeira Terminalia catappa (FFDA) como aditivo. Foram utilizados 28 machos de Bettas, acondicionados individualmente em aquários de 1,5L, por 50 dias. O experimento foi realizado em delineamento experimental inteiramente ao acaso, com quatro tratamentos: 0,00%; 0,25%; 0,50% e 0,75% de inclusão da FFAD e sete repetições. Ao término do experimento, foram avaliados os parâmetros: desempenho zootécnico (ganho de peso diário, consumo de ração, conversão alimentar aparente, taxa de eficiência proteica, taxa de crescimento específico e fator de condição), morfométrico (comprimento total, padrão e da cabeça, altura, índice de perfil e índice de cabeça), comportamento social, viabilidade econômica da ração, análise microbiana do conteúdo intestinal, filé e escama e análise microbiológica da água. Pela ANOVA, pelo teste de Tukey e pela regressão (P>0,05), os parâmetros: peso final, ganho de peso, comprimento padrão, comprimento total e taxa de crescimento específico foram influenciados pelos tratamentos (P<0,05), apresentando um efeito quadrático. Assim, recomenda-se o nível de 0,50% de Terminalia catappa como aditivo em dietas de Betta splendens.(AU)


The objective of this study was to evaluate the performance, morphometric parameters, social behavior, economic viability, the presence of enterobacteria in the intestinal contents and a microbiological analysis of the water culture of Betta splendens fed with almond-tree-leaf flour (ATLF) as an additive. Twenty-eight male B. splendens were individually put in 1.5 L aquariums. The experiment was done in a completely randomized experimental design with four treatments: 0.00%; 0.25%; 0.50% and 0.75%, of the ATLF, dehydrated Terminalia catappa with seven repetitions each. At the end of the experimental period, the parameters were evaluated: performance (daily weight gain, feed intake, apparent feed conversion, protein efficiency rate, specific growth rate and condition factor), morphometric (total length, standard head, height, profile index and head index), social behavior, economic viability of the feed, microbial analysis of intestinal contents, fillet and scales, and microbiological analysis of the water. Though ANAVA, Tukey test and regression analysis (P> 0.05), the parameters: final weight, weight gain, standard length, total length and specific growth rate were influenced by the treatments (P< 0.05), presenting a quadratic effect. Therefore, the 0.50% level of Terminalia catappa is recommended as additive in Betta splendens diets.(AU)


Assuntos
Animais , Perciformes/crescimento & desenvolvimento , Terminalia , Prebióticos/administração & dosagem
3.
Leukemia ; 25(6): 960-7, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21455214

RESUMO

Interleukin-7 (IL-7) activates phosphoinositide 3-kinase/Akt/mammalian target of rapamycin (PI3K/Akt/mTOR) pathway, thereby mediating viability, proliferation and growth of T-cell acute lymphoblastic leukemia (T-ALL) cells. Reactive oxygen species (ROS) can be upregulated by growth factors and are known to regulate proliferation and viability. Here, we show that IL-7 upregulates ROS in T-ALL cells in a manner that is dependent on PI3K/Akt/mTOR pathway activity and that relies on both NADPH oxidase and mitochondrial respiratory chain. Conversely, IL-7-induced activation of PI3K signaling pathway requires mitochondrial respiration and ROS. We have previously shown that IL-7-mediated activation of PI3K pathway drives the upregulation of the glucose transporter Glut1, promoting glucose uptake in T-ALL cells. Using phloretin to inhibit Glut function, we demonstrate that glucose uptake is mandatory for ROS upregulation in IL-7-treated T-ALL cells, suggesting that IL-7 stimulation leads to increased ROS via PI3K pathway activation and consequent upregulation of Glut1 and glucose uptake. Overall, our data reveal the existence of a critical crosstalk between PI3K/Akt signaling pathway and ROS that is essential for IL-7-mediated T-ALL cell survival, and that may constitute a novel target for therapeutic intervention.


Assuntos
Sobrevivência Celular , Interleucina-7/fisiologia , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patologia , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/fisiologia , Proliferação de Células , Humanos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor Cross-Talk , Serina-Treonina Quinases TOR/metabolismo , Células Tumorais Cultivadas , Regulação para Cima
6.
Arch Biochem Biophys ; 378(1): 131-41, 2000 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-10871053

RESUMO

A plasminogen activator enzyme (LV-PA) from Lachesis muta muta venom was purified to homogeneity using gel filtration and anion exchange chromatography. SDS-PAGE under reducing conditions showed a single protein band with an Mr of 33,000 Da. It is an acidic glycoprotein which activates plasminogen to plasmin indirectly, functioning via prior formation of a molecular complex, known as plasminogen activator. The purified preparation catalyzes the hydrolysis of several p-nitroanilide peptide substrates containing Lys at the scissile bond. In contrast, no hydrolysis was detected on the synthetic substrates TAME and BAPNA, which contain arginine. By the use of the plasmin-specific chromogenic substrate Tos-Gly-Pro-Lys-pNA, the preparation had a plasmin-like activity of 0.68 U/mg, which was 35.8-fold higher than that of the crude venom from which it was prepared. In vitro, fibrin hydrolysis using LV-PA as plasminogen activator displayed more similarity with the effect produced by streptokinase (SK). SDS-PAGE (10%) analysis showed a 115-kDa complex formation after incubation of plasminogen with either LV-PA or SK. At a molar ratio of 50:1 (fibrinogen:enzyme), the preparation exhibited weakly fibrinogenolytic activity. However, LV-PA is distinguished from thrombin in that it does not clot fibrinogen. After incubation of LV-PA with platelet-rich plasma, the enzyme (2 microM) showed no effect on platelet aggregation induced by ADP, epinephrine, or collagen. Comparison of the N-terminal sequence of LV-PA with other snake venom plasminogen activators revealed that LV-PA exhibits a high degree of sequence identity with the TsVPA from Trimeresurus stejnegeri (90%) and with the Haly-PA from Agkistrodon halys (85%). LV-PA also has homology with other snake venom serine proteinases such as the thrombin-like/gyroxin analogue (38%) from bushmaster venom and with other coagulation serine proteases. The proteinase was readily inhibited by treatment with p-nitrophenyl p-guanidinebenzoate, p-aminobenzamidine, and phenylmethanesulfonyl fluoride but was not affected by metal chelators.


Assuntos
Endopeptidases/isolamento & purificação , Ativadores de Plasminogênio/isolamento & purificação , Venenos de Víboras/enzimologia , Viperidae/metabolismo , Sequência de Aminoácidos , Animais , Caseínas/metabolismo , Endopeptidases/genética , Endopeptidases/farmacologia , Fibrinólise/efeitos dos fármacos , Humanos , Técnicas In Vitro , Dados de Sequência Molecular , Peso Molecular , Ativadores de Plasminogênio/genética , Ativadores de Plasminogênio/farmacologia , Agregação Plaquetária/efeitos dos fármacos , Homologia de Sequência de Aminoácidos , Especificidade por Substrato , Venenos de Víboras/química , Venenos de Víboras/genética , Viperidae/genética
7.
Br J Ophthalmol ; 83(4): 410-3, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10434861

RESUMO

AIMS: To describe the clinical course and treatment of Haemophilus influenzae associated scleritis. METHODS: Retrospective case series. RESULTS: Three patients developed scleritis associated with ocular H influenzae infection. Past medical history, review of systems, and laboratory testing for underlying collagen vascular disorders were negative in two patients. One patient had arthritis associated with an antinuclear antibody titre of 1:160 and a Westergren erythrocyte sedimentation rate of 83 mm in the first hour. Each patient had ocular surgery more than 6 months before developing scleritis. Two had cataract extraction and one had strabismus surgery. Nodular abscesses associated with areas of scleral necrosis were present in each case. Culture of these abscesses revealed H influenzae in all patients. Treatments included topical, subconjunctival, and systemic antibiotics. Scleral inflammation resolved and visual acuity improved in each case. CONCLUSION: H influenzae infection may be associated with scleritis. Accurate diagnosis and treatment may preserve ocular integrity and good visual acuity.


Assuntos
Infecções Oculares Bacterianas/tratamento farmacológico , Infecções por Haemophilus/tratamento farmacológico , Esclerite/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/uso terapêutico , Infecções Oculares Bacterianas/microbiologia , Feminino , Infecções por Haemophilus/complicações , Humanos , Estudos Retrospectivos , Esclerite/microbiologia , Acuidade Visual
8.
Ophthalmology ; 103(11): 1854-62; discussion 1862-3, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8942881

RESUMO

PURPOSE: The purpose of the study is to compare the clinical efficacy and safety of ciprofloxacin ophthalmic solution 0.3% (Ciloxan) with a standard therapy regimen (fortified tobramycin, 1.3%-cefazolin, 5.0%) for treating bacterial corneal ulcers. METHODS: This randomized, parallel group, double-masked, multicenter study was conducted in 324 patients at 28 centers in the United States, Europe, and India. Patients were randomized into 2 treatment groups: 160 to ciprofloxacin and 164 to fortified tobramycin-cefazolin. Positive microbiologic cultures were obtained in 188 (58%) of 324 patients. Of these, 176 patients met protocol criteria and were evaluated for treatment efficacy: 82 in the ciprofloxacin group and 94 in the standard therapy group. The dosing schedule for both treatment groups was 1 to 2 drops of the first study medication (ciprofloxacin or fortified tobramycin) every 30 minutes for 6 hours, then hourly for the remainder of day 1; 1 to 2 drops every hour on days 2 and 3; 1 to 2 drops every 2 hours on days 4 and 5, followed by 1 to 2 drops every 4 hours on days 6 to 14. The second medication (ciprofloxacin or cefazolin) was instilled 5 to 15 minutes after the first drug, following the same dosing frequency. Physician's judgment of clinical success, cure rate, changes in ocular sings, and symptoms and the rate of treatment failures were the primary efficacy criteria. RESULTS: Topical ciprofloxacin monotherapy is equivalent clinically and statistically to the standard therapy regimen of fortified antibiotics. No statistically significant treatment differences were found between ciprofloxacin (91.5%) and standard therapy (86.2%) in terms of overall clinical efficacy (P = 0.34). Similarly, no differences were noted in resolution of the clinical signs and symptoms (P > 0.08) or the time to cure (P = 0.55). The incidence of treatment failures was less in the ciprofloxacin group (8.5%) compared with the standard therapy group (13.8%). Significantly fewer patients treated with ciprofloxacin reported discomfort than did patients treated with the standard therapy regimen (P = 0.01). CONCLUSION: Ciprofloxacin ophthalmic solution 0.3% monotherapy is equivalent clinically and statistically to standard therapy (fortified tobramycin-cefazolin) for the treatment of bacterial corneal ulcers and produces significantly less discomfort.


Assuntos
Antibacterianos/uso terapêutico , Anti-Infecciosos/uso terapêutico , Cefazolina/uso terapêutico , Cefalosporinas/uso terapêutico , Ciprofloxacina/uso terapêutico , Úlcera da Córnea/tratamento farmacológico , Infecções Oculares Bacterianas/tratamento farmacológico , Tobramicina/uso terapêutico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/efeitos adversos , Anti-Infecciosos/efeitos adversos , Bactérias/isolamento & purificação , Cefazolina/efeitos adversos , Cefalosporinas/efeitos adversos , Criança , Ciprofloxacina/efeitos adversos , Córnea/microbiologia , Úlcera da Córnea/microbiologia , Método Duplo-Cego , Quimioterapia Combinada , Infecções Oculares Bacterianas/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Soluções Oftálmicas , Estudos Prospectivos , Tobramicina/efeitos adversos
9.
Am J Ophthalmol ; 122(2): 171-82, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8694085

RESUMO

PURPOSE: Two multicenter studies compared the efficacy and safety of rimexolone 1% ophthalmic suspension (Vexol 1%, Alcon) and 1% prednisolone acetate (Pred Forte, Allergan). METHODS: Patients with acute uveitis, recurrent iridocyclitis, or chronic uveitis treatable by topical corticosteroid were enrolled. Treatment regimen was one or two drops every hour during Week 1, every two hours during Week 2, four times a day during Week 3, and once a day for the last three days. Efficacy and safety were determined on Days 3, 4, 7 to 10, 14, 21, and 28. A poststudy evaluation was conducted 36 to 72 hours after treatment was stopped. RESULTS: When anterior chamber cell and flare were measured, rimexolone 1% was found to be as effective as 1% prednisolone. The largest difference observed between treatments was 0.5 score unit, not clinically significant. There were no statistically significant differences in cell scores in either study (P > .05). No statistically significant differences in flare scores were found except at Day 28 in Study One (P = .04). Also, prednisolone was found to be more likely than rimexolone to cause a clinically significant increase (10 mm Hg or more) in intraocular pressure (1.7 times more likely in Study One, eight times more likely in Study Two). CONCLUSION: Rimexolone 1% ophthalmic suspension is safe and effective for the treatment of uveitis.


Assuntos
Anti-Inflamatórios/uso terapêutico , Prednisolona/uso terapêutico , Pregnadienos/uso terapêutico , Uveíte/tratamento farmacológico , Doença Aguda , Administração Tópica , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Câmara Anterior/efeitos dos fármacos , Câmara Anterior/patologia , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/efeitos adversos , Criança , Doença Crônica , Método Duplo-Cego , Feminino , Humanos , Pressão Intraocular/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Soluções Oftálmicas , Prednisolona/administração & dosagem , Prednisolona/efeitos adversos , Pregnadienos/administração & dosagem , Pregnadienos/efeitos adversos , Recidiva , Segurança , Suspensões
10.
Am J Ophthalmol ; 117(4): 488-97, 1994 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-8154531

RESUMO

A multicenter, randomized, double-masked, parallel-group study compared the long-term efficacy and safety of lodoxamide 0.1% ophthalmic solution and placebo in 118 patients with vernal keratoconjunctivitis. The test drugs were instilled four times daily for 90 days. Lodoxamide 0.1% ophthalmic solution was significantly (P < .05) more effective than placebo in lowering severity scores for epithelial disease and corneal staining, evidence of the superior efficacy of lodoxamide 0.1% ophthalmic solution in reversing the corneal complications commonly associated with moderate to severe vernal keratoconjunctivitis. Additionally, lodoxamide 0.1% ophthalmic solution ameliorated the other key signs of vernal keratoconjunctivitis, including upper tarsal papillae, limbal signs (papillae, hyperemia, and Trantas' dots), and conjunctival discharge. The between-group differences in the relief of symptoms (itching, tearing, and photophobia) were clinically significant but not always statistically significant. Treatment-related adverse events were reported with similar frequency in both treatment groups, and none were serious.


Assuntos
Conjuntivite Alérgica/tratamento farmacológico , Doenças da Córnea/tratamento farmacológico , Ácido Oxâmico/análogos & derivados , Adolescente , Adulto , Idoso , Análise de Variância , Criança , Pré-Escolar , Conjuntivite Alérgica/complicações , Doenças da Córnea/etiologia , Método Duplo-Cego , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Soluções Oftálmicas , Ácido Oxâmico/administração & dosagem , Ácido Oxâmico/efeitos adversos
11.
Ann Ophthalmol ; 16(11): 1030-2, 1984 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-6517437
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