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1.
Bioresour Technol ; 143: 298-307, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23810951

RESUMO

An investigation of the potential to efficiently convert lipid-depleted residual microalgae biomass using thermochemical (gasification at 850 °C, pyrolysis at 550 °C, and torrefaction at 300 °C) processes to produce bioenergy derivatives was made. Energy indicators are established to account for the amount of energy inputs that have to be supplied to the system in order to gain 1 MJ of bio-energy output. The paper seeks to address the difference between net energy input-output balances based on a life cycle approach, from "cradle-to-bioenergy co-products", vs. thermochemical processes alone. The experimental results showed the lowest results of Net Energy Balances (NEB) to be 0.57 MJ/MJ bio-oil via pyrolysis, and highest, 6.48 MJ/MJ for gas derived via torrefaction. With the complete life cycle process chain factored in, the energy balances of NEBLCA increased to 1.67 MJ/MJ (bio-oil) and 7.01 MJ/MJ (gas). Energy efficiencies and the life cycle CO2 emissions were also calculated.


Assuntos
Biomassa , Dióxido de Carbono/metabolismo , Microalgas/metabolismo
2.
Arch Dis Child Fetal Neonatal Ed ; 94(5): F349-54, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19477913

RESUMO

OBJECTIVE: To conduct a systematic review of the efficacy of music for medical indications in term or preterm neonates. METHODS: We searched 17 electronic databases, subject bibliographies, reference lists and trials registries. Two reviewers independently screened studies for inclusion, assessed methodological quality, and extracted data. Meta-analysis was not feasible due to heterogeneity in outcomes so a qualitative analysis is presented. RESULTS: Nine randomised trials were included. The methodological quality was generally poor (median Jadad score = 1). The outcomes most commonly reported were physiological measures (heart rate (HR), respiratory rate, oxygen saturation (SaO2)), behavioural state and pain. Six studies evaluated music for the painful procedures circumcision (three trials) and heel prick (three trials). For circumcisions, one high quality pilot study (n = 23) showed benefits of music for the outcomes of HR, SaO2 and pain, while two low quality studies showed no difference. For heel prick, three low quality studies provided some evidence that music may be beneficial primarily for measures of behaviour and pain. The remaining studies evaluated the use of music in preterm infants to improve physiological and behavioural parameters (n = 31; benefits observed for behavioural parameters), to reinforce non-nutritive sucking via use of a pacifier activated lullaby (n = 32; significant increase in feeding rates), and to influence physiological stability and behaviours in infants with chronic lung disease (n = 22; no significant differences for outcomes assessed). CONCLUSIONS: The heterogeneity in study populations, interventions and outcomes precludes definitive conclusions around efficacy. There is preliminary evidence for some therapeutic benefits of music for specific indications; however, these findings need to be confirmed in methodologically rigorous trials.


Assuntos
Música/psicologia , Dor/psicologia , Comportamento de Sucção/fisiologia , Humanos , Recém-Nascido , Dor/prevenção & controle , Ensaios Clínicos Controlados Aleatórios como Assunto
3.
Indian J Pediatr ; 68(9): 829-34, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11669029

RESUMO

OBJECTIVES: To assess the validity of SNAP in predicting the outcome in terms of mortality and duration of hospital stay. The study was also undertaken to evolve the best cut-off SNAP scores for predicting mortality in different individual neonatal conditions. METHODS: 295 consecutive newborn admitted to NICU during an eleven month period were evaluated with the investigations required as per the specifications of SNAP. Neonates who succumbed within 24 hours of admission and those who were shifted to the NICU for observation purposes were excluded. RESULTS: In general, SNAP correlated well with mortality; the sensitivity and specificity of SNAP score > 15 in predicting mortality were 63% and 95% respectively. The positive and negative predictive values were 72% and 92.5% respectively. Very low birth weight babies and ventilated preterm neonates had higher mortality and the best cut-off SNAP score for predicting mortality in these groups was 10. In all the other groups, SNAP score > 15 correlated well with higher mortality. By using multiple regression analysis on three variables including birth weight, gestational age and SNAP, SNAP was found to show the best correlation with mortality. On correlating SNAP with duration of hospital stay, 76.8% of the surviving neonates with SNAP < 16 stayed for < 15 days, whereas the rest stayed longer despite low SNAP. All the 9 babies with SNAP > 15 who survived stayed for > 15 days. CONCLUSIONS: SNAP is a measure of illness severity and correlates well with neonatal mortality. SNAP may assist the clinician in explaining the probable outcome and therapeutic intervention needed and the cost of treatment to the parents. SNAP scores > 10 in VLBW babies and > 15 in others are associated with higher mortality.


Assuntos
Mortalidade Infantil , Doenças do Recém-Nascido/diagnóstico , Doenças do Recém-Nascido/mortalidade , Triagem Neonatal , Feminino , Humanos , Índia/epidemiologia , Recém-Nascido , Doenças do Recém-Nascido/terapia , Unidades de Terapia Intensiva Neonatal , Masculino , Estudos Prospectivos , Curva ROC , Reprodutibilidade dos Testes , Fatores de Risco , Índice de Gravidade de Doença
4.
Eur J Pharm Sci ; 14(3): 217-20, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11576826

RESUMO

Melatonin is a good candidate for transdermal delivery considering its short plasma half life, low molecular weight and a favorable octanol:water partition coefficient. Nimesulide is a nonsteroidal anti-inflammatory agent used orally and rectally for inflammatory disorders. The objective of this study was to investigate the skin sensitization potential of melatonin and nimesulide using the standard murine local lymph node assay (LLNA). Melatonin (0.5, 2.5, 5.0 and 10.0%, w/v) and nimesulide (0.5, 2.5, 5.0 and 10.0%, w/v) dissolved in acetone:olive oil (4:1, AOO) was applied (25 microl) on the dorsal surface of each ear of female CBA/Ca mice for three consecutive days. On the sixth day, [3H]methyl thymidine was administered intravenously and the uptake of [3H]methyl thymidine (dpm) by the draining lymph nodes was determined by established methods. Dinitrochlorobenzene (DNCB, 0.25%, w/v) and para-aminobenzoic acid (PABA, 2.5%, w/v) were used as positive and negative control, respectively. The mean dpm obtained with melatonin and nimesulide treatment at all concentrations were not significantly different (P>0.05) from that of AOO. The stimulation index (SI) values of melatonin and nimesulide at different concentrations were close to 1. The results of the present study using the standard LLNA approved by US Interagency Coordinating Committee in the Validation of Alternative Methods (ICCVAM) indicate that melatonin and nimesulide are not skin sensitizers. However, since LLNA has shown false negatives with many drugs, clinical trials are certainly needed to exclude the possibility of a weak or delayed type skin sensitization reaction. Further studies using modified LLNA procedures (extended exposure, alternative vehicle systems, pre-abrasion, etc.) may be useful in identifying the weak or delayed type skin sensitization reactions.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Melatonina/farmacologia , Pele/efeitos dos fármacos , Sulfonamidas/farmacologia , Animais , Inibidores de Ciclo-Oxigenase/farmacologia , Dinitroclorobenzeno , Relação Dose-Resposta a Droga , Linfonodos/efeitos dos fármacos , Camundongos , Pele/imunologia
5.
J Pharm Pharmacol ; 53(5): 617-27, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11370701

RESUMO

The carboxylic ionophore monensin was formulated into long-circulating nanoparticles with the help of polyethylene glycol/poly (DL-lactide-co-glycolide) diblock copolymers, in an attempt to enhance the cytotoxicity of a ricin-based immunotoxin, anti-My9, and anticancer drugs like adriamycin and tamoxifen. This study looked into various aspects involving the preparation (using a homogenizer and an EmulsiFlex homogenizer-extrusion device) and lyophilization of long-circulating monensin nanoparticles (LMNP) of particle size < 200 nm in diameter. The particle size of LMNP was reduced from 194 nm to 160 nm by passing the nanoparticles through an EmulsiFlex, before freeze-drying. There was a 4.8-83.7% increase in the particle size of LMNP after freeze-drying, which was dependent upon the manufacturing conditions such as use of the EmulsiFlex for size reduction before freeze-drying, the freezing method (rapid/slow) and the concentration of lyoprotectant (mannitol or trehalose) employed for freeze-drying. LMNP freeze-dried with 2.4% of trehalose showed minimal size change (< 9%) after freeze-drying. Further, the freezing method was found to have negligible effect on the particle size of LMNP freeze-dried with trehalose in comparison with mannitol. The entrapment efficiency of monensin in LMNP was found to be 14.2 +/- 0.3%. The LMNP were found to be spherical in shape and smooth in surface texture as observed by atomic force microscopy. In-vitro release of monensin from LMNP in phosphate buffered saline (PBS) pH 7.4 or PBS supplemented with 10% human serum indicated that there was an initial rapid release of about 40% in the first 8 h followed by a fairly slow release (about 20%) in the next 88 h. In-vivo studies conducted with Sprague-Dawley rats showed that 20% of monensin remained in circulation 4-8 h after the intravenous administration of LMNP. An in-vitro dye-based cytotoxicity assay (MTS/PMS method) showed that there was 500 times and 5 times potentiation of the cytotoxicity of anti-My9 immunotoxin by LMNP (5 x 10(-8) M of monensin) in HL-60 sensitive and resistant human tumour cell lines, respectively. Further, LMNP (5 x 10(-8) M of monensin) potentiated the cytotoxicity of adriamycin in MCF 7 and SW 620 cell lines by 100 fold and 10 fold, respectively, and that of tamoxifen by 44 fold in MCF 7 cell line as assessed by crystal violet dye uptake assay. Our results suggest that it is possible to prepare LMNP possessing appropriate particle size (< 200 nm), monensin content and in-vitro and in-vivo release characteristics with the help of a homogenizer and an EmulsiFlex homogenizer-extrusion device. LMNP can be freeze-dried with minimal increase in particle size by using a suitable concentration of a lyoprotectant like trehalose. Furthermore, LMNP could potentiate the cytotoxicity of immunotoxin, adriamycin and tamoxifen by 5-500 fold in-vitro, which will be further investigated in-vivo in a suitable animal model.


Assuntos
Antifúngicos/farmacocinética , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos/farmacologia , Doxorrubicina/farmacologia , Imunotoxinas/farmacologia , Monensin/farmacocinética , Ricina/farmacologia , Tamoxifeno/farmacologia , Animais , Antifúngicos/imunologia , Antifúngicos/farmacologia , Interações Medicamentosas , Excipientes/química , Liofilização , Meia-Vida , Concentração de Íons de Hidrogênio , Monensin/imunologia , Monensin/farmacologia , Tamanho da Partícula , Polietilenoglicóis/química , Polímeros , Ratos , Ratos Sprague-Dawley
6.
Toxicol Lett ; 119(2): 133-42, 2001 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-11311575

RESUMO

JP-8 is the major jet fuel used by US Air Force. JP-8+100 is a new jet fuel recently introduced by the US Air Force, which contains JP-8 plus three performance additives [butylated hydroxytoluene (BHT), metal deactivator (MDA) and 8Q405]. The purpose of the present study was to investigate the percutaneous permeation of JP-8+100 across pig ear skin in vitro and to study the effect of JP-8+100 exposure on the skin barrier function, moisture content and irritation in Yucatan minipigs. The influence of performance additives on the permeation of JP-8 was studied by adding each additive individually to JP-8. The percutaneous permeation and skin irritation data obtained with JP-8+100 were compared with that of JP-8. JP-8+100 spiked with 5.0 microCi of radiolabeled [14C]tridecane, nonane, naphthalene or toluene (selected components of JP-8+100) was used for the in vitro percutaneous permeation studies. For skin irritation studies, 250 microl of JP-8+100 was placed in a Hill top chamber and affixed over the marked treatment area for 24 h. The components of JP-8+100 such as tridecane, nonane, naphthalene and toluene permeated readily through pig ear skin without any apparent lag time. Compared to JP-8, the permeation of tridecane, toluene and nonane from JP-8+100 was significantly lower (P<0.05). However, the permeation of naphthalene from JP-8+100 was significantly higher than from JP-8. When BHT was added to JP-8, the permeation of all four chemicals were significantly decreased (P<0.05). Though the addition of 8Q405 to JP-8 decreased the permeation of all four chemicals, the values were not significantly different (P>0.05) from that of JP-8. Addition of MDA did not show any significant change in the permeation of the selected chemicals from JP-8. Application of JP-8+100 increased the transepidermal water loss (TEWL) about three times compared to the baseline level. The skin moisture content decreased consistently after the application of JP-8+100, though it was not significantly different (P>0.05) from the baseline level. JP-8+100 caused a moderate erythema (score: 1.60) and a moderate to severe edema (score: 2.60). These results suggest that JP-8+100 produces significant changes in the barrier function of the skin and a local irritant effect upon occlusive dermal exposure. However there was no significant difference in the skin irritation data observed from JP-8 and JP-8+100.


Assuntos
Hidrocarbonetos/toxicidade , Dermatopatias/induzido quimicamente , Pele/efeitos dos fármacos , Teratogênicos/toxicidade , Administração Cutânea , Animais , Orelha , Masculino , Modelos Animais , Pele/metabolismo , Suínos , Água/fisiologia
7.
Toxicology ; 161(1-2): 1-11, 2001 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-11295251

RESUMO

JP-8 is the major jet fuel used by US Army and Air Force. The purpose of the present study was to investigate the percutaneous absorption of JP-8 across pig ear skin and human skin in vitro and to study the effect of JP-8 exposure on the skin barrier function and irritation in Yucatan minipigs. JP-8 spiked with 5.0 microCi of radiolabeled (14C) tridecane, nonane, naphthalene or toluene (selected components of JP-8) was used for the in vitro percutaneous absorption studies with excised pig ear skin and human skin. For in vivo studies, 250 microl of JP-8 or two of its components (toluene or nonane) was placed in a Hill top chamber(R) and affixed over the marked treatment area for 24 h. Transepidermal water loss (TEWL), skin capacitance (moisture content) and skin irritation (erythema and edema) were evaluated before treatment and at 1,2 and 24 h after removal of the patches. The components of JP-8 such as tridecane, nonane, naphthalene and toluene permeated significantly through pig ear skin and human skin and the permeation rates were found to be proportional to their composition in JP-8. The steady state flux values of tridecane across pig ear skin and human skin did not differ significantly (P>0.05). Though the steady state flux values of nonane, naphthalene and toluene were statistically different between porcine and human skin (P<0.01), the values were close considering the large variations usually observed in the percutaneous absorption studies. Application of toluene, nonane or JP-8 increased the TEWL, JP-8 being the highest (3.5 times at 24 h compared to baseline level). The skin moisture content decreased after the application of JP-8, though it was not significantly different (P>0.05) from the baseline level. JP-8 caused a moderate erythema and a moderate to severe edema. Though the edema decreased after 24 h, the degree of erythema remained about the same until 24 h. The skin irritation caused by JP-8 was greater than neat toluene or nonane. The TEWL data of toluene, nonane and JP-8 correlated well with the skin irritation data (erythema and edema). Exposure of JP-8, which contains hundreds of aliphatic and aromatic hydrocarbons, caused significant changes in the barrier function of the skin as indicated by an increase in TEWL and produced a significant erythema and edema in minipigs. Furthermore, the disruption of barrier function of skin, as indicated by increased TEWL after exposure to JP-8 might result in increased permeation of its own components and/or other chemicals exposed to skin. The present study provides further evidence that pig ear skin may be used as a model for predicting the rates of permeation of chemicals through human skin.


Assuntos
Eritema/induzido quimicamente , Petróleo/toxicidade , Absorção Cutânea , Administração Cutânea , Animais , Cromatografia Gasosa , Orelha , Humanos , Hidrocarbonetos/administração & dosagem , Hidrocarbonetos/análise , Hidrocarbonetos/toxicidade , Masculino , Petróleo/análise , Porco Miniatura
8.
Tex Heart Inst J ; 27(3): 292-6, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11093416

RESUMO

Dual left anterior descending artery (or dual anterior interventricular artery) is a rare coronary anomaly. It is important to know the anatomic variants of this anomaly in patients with coronary artery disease who are undergoing either surgical myocardial revascularization or coronary angioplasty. We report the cases of 4 patients who had anatomic variants of dual left anterior descending coronary artery. These patients had developed coronary artery disease in the long or the short left anterior descending artery, or in both. The long left anterior descending artery was diseased in 1 patient, and the short left anterior descending artery was diseased in another In the 3rd and 4th patients, both the long and the short arteries were atherosclerotic and had developed severe stenosis. All 4 patients underwent successful myocardial revascularization. There was no electrocardiographic evidence of perioperative myocardial infarction. All patients were asymptomatic during the follow-up period, which ranged from 3 months to 1.5 years. Angiographers and surgeons alike must be aware of the variants of dual left anterior descending coronary artery, so that the diseased vessels can be correctly identified even if 1 of the dual arteries is 100% occluded.


Assuntos
Doença das Coronárias/cirurgia , Anomalias dos Vasos Coronários/cirurgia , Revascularização Miocárdica , Angiografia Coronária , Doença das Coronárias/complicações , Doença das Coronárias/diagnóstico por imagem , Anomalias dos Vasos Coronários/complicações , Anomalias dos Vasos Coronários/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade
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