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1.
Drug Dev Ind Pharm ; 48(5): 198-210, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35726510

RESUMO

OBJECTIVE: Patient acceptance of pediatric formulations is critical to compliance and consequently therapeutic outcomes; thus, having an in vitro method to evaluate sensory perception of pharmaceutical products would be beneficial. The objective of this research is to develop a sensitive and reproducible tribological method to characterize pharmaceutical suspensions at low force and sliding speeds. METHODS: The discriminating potential of the method was examined using tribology profiles (coefficient of friction (COF) vs. sliding speed) for commercially available products and products made for this study with widely varying sweetness, thickness, and grittiness; these formulations were used to judge the sensitivity of the method. Samples were measured using 3M Transpore™ surgical tape to simulate the tongue surface, steel half ring geometry, constant gap setting, target axial force of 2 N in a 600 s exponential ramp for rotation speed. RESULTS: The COF ranged from 0.1 to 0.6. For the speeds studied, the high viscosity commercial suspension ibuprofen drops and acetaminophen suspension show a classic Stribeck curve with an increasing COF at the higher rotation speeds, which indicates these formulations entered the hydrodynamic lubrication phase, while the lower viscosity suspensions only reached the mixed lubrication phase. CONCLUSION: The contribution of particles affects the COF in a dynamic tribologic pattern compared to products that are categorized as either low gritty or high viscosity. These results are important as they provide a potentially rapid in vitro method for screening pediatric medications and help to identify the factors that affect the palatability of pediatric formulations.


Assuntos
Composição de Medicamentos , Suspensões , Criança , Fricção , Humanos , Lubrificação , Viscosidade
2.
Menopause ; 24(6): 669-676, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28072610

RESUMO

OBJECTIVE: To assess sexual activity, sexual function, and their correlation with vaginal maturation status among middle-aged Chinese women. METHODS: A cross-sectional study with comparisons across age groups was carried out. In all, 120 women aged 45 to 60 years were recruited into three groups: 45 to 50 (youngest group), 51 to 55 (intermediate group), and 56 to 60 years old (eldest group). Sexual function was assessed through the Female Sexual Function Index (FSFI); vaginal maturation status was determined through the Vaginal Maturation Index (VMI) and pH value. Sexual activity was recorded with self-administered questionnaires. RESULTS: Low sexual frequency was present in a higher proportion of women, but sexual distress was identified within a lower proportion of women in the eldest group. The total FSFI score was significantly lower in the eldest group than in the youngest and intermediate groups (P < 0.01 and 0.05, respectively); however, the domain score of sexual desire, arousal, and satisfaction was lower in the eldest group than in the youngest group (P < 0.01, 0.05, and 0.05) only. The domain score for lubrication was lower in the eldest group than in both the youngest and intermediate groups (P < 0.01 and 0.05), and the pain score was lower in both the intermediate and eldest groups than in the youngest group (P < 0.01 and 0.05). A lower VMI (P < 0.001) and a higher pH value (P < 0.01) were observed in the eldest group, compared with the youngest group. Moreover, VMI was positively correlated with the total FSFI score, the domain score for sexual desire, and lubrication (r = 0.26, 0.25, 0.34; P < 0.05, 0.05, 0.01), but the opposite associations were demonstrated for pH value (r = -0.47, -0.37, -0.38; P < 0.01, respectively), especially with vaginal pain (r = -0.44, P < 0.01). CONCLUSIONS: Among middle-aged Chinese women, sexual desire is lower in 56 to 60-year-old women, compared with those aged 45 to 55 years, whereas vaginal dryness and dyspareunia become more prevalent with age. Importantly, sexual function is associated with vaginal maturation status in women at midlife.


Assuntos
Comportamento Sexual/fisiologia , Vagina/fisiopatologia , Fatores Etários , China/epidemiologia , Estudos Transversais , Dispareunia , Feminino , Humanos , Libido/fisiologia , Lubrificação , Menopausa/fisiologia , Pessoa de Meia-Idade , Disfunções Sexuais Fisiológicas/epidemiologia , Inquéritos e Questionários , Doenças Vaginais/fisiopatologia , Esfregaço Vaginal
3.
J Pharm Sci ; 106(2): 537-545, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27832838

RESUMO

The predictability of multivariate calibration models, calculated with offline near-infrared spectroscopy (NIRS), assessing impact of magnesium stearate (MgSt) fraction, blending time, and compression force on the tablet breaking force (TBF) of SPRESS® B820 was statistically compared. Tablets of lubricated SPRESS® B820 were prepared by varying lubrication and compression conditions using 24 full factorial design. Tablets were scanned in reflection mode on a benchtop NIRS. A qualitative principal component analysis and quantitative principal component regression (PCR) and partial least square (PLS) regression relationship between lubricant concentration, blending time, compression force, preprocessed NIR spectra, and measured TBF was calculated with calibration data set. The predictability of calibration models was validated with independent data set. Expected qualitative correlations between MgSt blending time and TBF and a nonlinear relationship between MgSt fraction and TBF were observed. Predictability of PLS comprehensive (0.25%-1% w/w MgSt) model was significantly different from individual 0.25%, 0.5%, and 1.0% w/w MgSt PLS models. In addition, PLS calibration models' predictability was different from PCR calibration models. Thus, added lubrication fraction and adopted multivariate methodology should be selected carefully during the calibration and validation stages as it may have a significant impact on the predictability of the developed models.


Assuntos
Lubrificantes/química , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Calibragem , Composição de Medicamentos , Análise dos Mínimos Quadrados , Lubrificação , Análise Multivariada , Análise de Componente Principal , Comprimidos
4.
Food Funct ; 8(2): 563-573, 2017 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-27722602

RESUMO

This study aims to investigate the relationship between rheological and tribological properties of commercial full fat and fat-free/low fat versions of liquid and soft solid colloidal systems (milk, yoghurt, soft cream cheese) with their sensory properties. Oscillatory measurements (strain, frequency), flow curves and tribological measurements (lubrication behaviour using Stribeck analysis) were conducted. Oral condition was mimicked using artificial saliva at 37 ○C. Discrimination test was conducted by 63 untrained consumers, followed by a qualitative questionnaire. Consumers significantly discriminated the fat-free/low fat from the full fat versions (p < 0.01) in all product classes, with most common verbatim used being "creamy", "sweet" for the full fat versus "watery", "sour" for the fat-free samples. Flow behaviour of both versions of milk showed overlapping trends with no significant differences identified both in absence and presence of saliva (p > 0.05). Full fat and fat free yoghurts had similar yielding behaviour and elastic modulus (G'), even in simulated oral conditions. However, in case of soft cream cheese, the full fat version had a moderately higher G' than the low fat counterpart. Even in presence of artificial saliva, there was slight but significant difference in viscoelasticity between the cream cheese variants depending on fat content (p < 0.05). Stribeck curve analyses showed that at lower entrainment velocities (1-100 mm s-1), both full fat yoghurt and soft cream cheese exhibited a significantly lower traction coefficient when compared to fat-free/low fat versions (p < 0.05), which might be attributed to the lubricating effect of the coalesced fat droplets. Surprisingly, whole and skim milks showed no significant difference in traction coefficients irrespective of the entrainment speeds (p > 0.05). Results suggest that sensory distinction between fat-free and full fat versions, particularly in semi-solid systems could be better predicted by lubrication data as compared to bulk rheology.


Assuntos
Queijo/análise , Leite/química , Percepção Gustatória , Iogurte/análise , Adulto , Animais , Queijo/economia , Coloides/química , Coloides/metabolismo , Feminino , Humanos , Lubrificação , Masculino , Pessoa de Meia-Idade , Leite/economia , Reologia , Viscosidade , Iogurte/economia , Adulto Jovem
5.
Climacteric ; 18 Suppl 1: 9-12, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26366794

RESUMO

The vagina is a most neglected organ. It is usually clinically considered with a minimalistic view, as a 'connecting tube' for a number of physiologic functions: passage of menstrual blood, intercourse, natural conception and delivery. Unmet needs include, but are not limited to, respect of vaginal physiologic biofilms; diagnosis and care of the optimal tone of the levator ani, which surrounds and partly support it; care of its anatomic integrity at and after delivery and at pelvic/vaginal surgery; care of long-term consequences of pelvic radiotherapy; long-term care of the atrophic changes it will undergo after the menopause, unless appropriate, at least local, estrogen therapy is used; appreciation and respect of its erotic meaning, as a loving, receptive, 'bonding' organ for the couple. The vaginal erotic value is key as a non-visible powerful center of femininity and sexuality, deeply and secretly attractive in terms of taste, scent (together with the vulva), touch and proprioception. The most welcoming when lubrication, softness and vaginal orgasm award the woman and the partner with the best of pleasures. Prevention of sexual/vaginal abuse is a very neglected unmet need, as well. Who cares?


Assuntos
Saúde Reprodutiva , Vagina/fisiologia , Canal Anal/fisiologia , Atrofia , Biofilmes , Coito , Parto Obstétrico , Estrogênios/fisiologia , Feminino , Ginecologia/métodos , Hormônios/fisiologia , Humanos , Lubrificação , Menopausa/fisiologia , Tono Muscular , Orgasmo/fisiologia , Dor , Diafragma da Pelve/fisiologia , Comportamento Sexual/fisiologia , Sexualidade/fisiologia , Vagina/microbiologia , Vagina/patologia , Vulva/fisiologia
6.
Chemosphere ; 89(9): 1135-41, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22749125

RESUMO

This paper reports on the (eco)toxicity and biodegradability of ionic liquids considered for application as lubricants or lubrication additives. Ammonium- and pyrrolidinium-based cations combined with methylsulphate, methylsulphonate and/or (CF(3)SO(2))(2)N(-) anions were investigated in tests to determine their aquatic toxicity using water fleas Daphnia magna, green algae Selenastrum capricornutum and marine bacteria (Vibrio fischeri). Additional test systems with an isolated enzyme (acetylcholinesterase) and isolated leukaemia cells from rats (IPC-81) were used to assess the biological activity of the ionic liquids. These compounds generally exhibit low acute toxicity and biological activity. Their biodegradability was screened according to OECD test procedures 301 B and 301 F. For choline and methoxy-choline ionic liquids ready biodegradability was observed within 5 or 10 d, respectively. Some of the compounds selected have a considerable potential to contribute to the development of more sustainable products and processes.


Assuntos
Líquidos Iônicos/toxicidade , Lubrificantes/toxicidade , Biodegradação Ambiental , Líquidos Iônicos/análise , Líquidos Iônicos/química , Líquidos Iônicos/metabolismo , Lubrificantes/análise , Lubrificantes/química , Lubrificantes/metabolismo , Lubrificação , Medição de Risco , Testes de Toxicidade
7.
J Sex Med ; 8(12): 3389-97, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21951616

RESUMO

INTRODUCTION: The effect of systemic lupus erythematosus (SLE) on women's sexual functioning has been rarely assessed. AIM: The aim of this study is to evaluate the impact of SLE on women's sexual functioning. METHODS: A total of 302 consecutive female outpatients with SLE were provided with a questionnaire composed of the Female Sexual Function Index (FSFI), questions for sociodemographic characteristics and comorbidities. Similarly, 2,159 hospital female employees were assessed as the control group. In patients, data of SLE duration and Sjögren's syndrome were derived from the chart records and the disease activity was assessed using the SLE Disease Activity Index 2000. MAIN OUTCOME MEASURES: The FSFI scores were compared between the patients and the controls. Correlates of the FSFI scores were determined in the patients. RESULTS: Of 302 eligible patients, 92.4% (279/302) responded, in addition to 73.2% (1,580/2,159) of controls. Ninety-five percent (255/268) of the respondent patients were in no-to-mild SLE disease activity. Among the respondents, 171 (61.3%) patients and 930 (58.9%) controls were sexually active in the previous month, P = 0.446. Of the sexually active patients, 52.5% (85/162) had impaired sexual function (the FSFI total score < 26.55) and so did 47.1% (408/867) of the sexually active controls, P = 0.206. With adjustment of age group, marital status and education level, patients had lower FSFI scores than controls only in the domains of lubrication and pain. Significant risk factors for lower FSFI scores in the patients included persistent activity or flare of SLE, menstrual cycle disturbances, and vascular disease. With further adjustment of other risk factors, only vascular disease remained significant as a risk factor for impaired sexual function (odds ratio = 5.7; 95% confidence interval 1.6-20.1). CONCLUSION: When not in an exacerbation period, the impact of SLE on women's sexual functioning is not great and is related to vascular factors.


Assuntos
Lúpus Eritematoso Sistêmico/psicologia , Disfunções Sexuais Fisiológicas/etiologia , Sexualidade/psicologia , Síndrome de Sjogren/psicologia , Estresse Psicológico/complicações , Doenças Vasculares/complicações , Adaptação Psicológica , Adulto , Idoso , Estudos de Casos e Controles , Estudos Transversais , Feminino , Indicadores Básicos de Saúde , Humanos , Modelos Logísticos , Lubrificação , Pessoa de Meia-Idade , Razão de Chances , Orgasmo , Pacientes Ambulatoriais , Fatores de Risco , Índice de Gravidade de Doença , Disfunções Sexuais Fisiológicas/psicologia , Estresse Psicológico/psicologia , Inquéritos e Questionários , Fatores de Tempo , Doenças Vasculares/psicologia , Adulto Jovem
8.
Sex Health ; 7(2): 193-8, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20465986

RESUMO

BACKGROUND: The importance of the acceptability of rectal microbicides for HIV and sexually transmissible infections (STIs) prevention is widely recognised. Given relatively consistent use of lubricants for anal intercourse (AI) and the potential for lubricant-like rectal microbicides, understanding barriers to lubricant use may help inform hurdles likely to be encountered once a rectal microbicide becomes available. METHODS: We conducted an internet-based survey using a 25-item questionnaire to assess AI and lubricant use, including lubricant preferences and barriers to use. RESULTS: The majority of the 6124 respondents who reported AI were male (93%), 25 years or older (80%) and from North America (70%). Consistent condom use during AI was reported by a minority (35%) and consistent lubricant use was reported by over half of respondents. Reasons for non-use differed by age and region. Among men, those <25 years were more likely to report barriers around cost compared with those 45 and older (odds ratio (OR) = 6.64; 95% confidence interval (CI) 3.14-14.03). European men (OR = 1.92; 95% CI 1.50-2.45), Latin American women (OR = 3.69; 95% CI 1.27-10.75) and Asian women (OR = 4.04; 95% CI 1.39-11.78) were more likely to report sexual preference as a reason for non-use. CONCLUSIONS: Rectal lubricants are widely used, but barriers to use vary by age and region for dry sex. A lubricant-like rectal microbicide would potentially be acceptable and such a product may be useful as a method of HIV prevention. However, targeted marketing and educational approaches may be needed to enhance use and acceptability of such a product.


Assuntos
Anti-Infecciosos Locais/administração & dosagem , Conhecimentos, Atitudes e Prática em Saúde , Lubrificantes/administração & dosagem , Lubrificação/métodos , Comportamento Sexual/estatística & dados numéricos , Administração Retal , Adulto , Canal Anal , Coito , Intervalos de Confiança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Doenças Virais Sexualmente Transmissíveis/prevenção & controle , Inquéritos e Questionários , Adulto Jovem
9.
J Biomech ; 43(9): 1787-93, 2010 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-20189572

RESUMO

During joint articulation, cartilage is subjected to compression, shear, and sliding, mechanical factors that regulate and affect cartilage metabolism. The objective of this study was to use an in vitro material-on-cartilage shear test to elucidate the effects of counter-surface roughness (Polished, Mildly rough, and Rough), lubricants (phosphate buffered saline (PBS) and bovine synovial fluid (bSF)), and compression offset on the shearing and sliding of normal human talar cartilage under dynamic lateral displacement. Peak shear stress (sigma(xz,m)) and strain (E(xz,m)) increased with increasing platen roughness and compression offset, and were 30% higher with PBS than with bSF. Compared to PBS, bSF was more effective as a lubricant for P than for M and R platens as indicated by the higher reduction in kinetic friction coefficient (-60% vs. -20% and -19%, respectively), sigma(xz,m) (-50% vs. -14% and -17%) and E(xz,m) (-54% vs. -19% and -17%). Cartilage shear and sliding were evident for all counter-surfaces either at low compression offset (10%) or with high lateral displacement (70%), regardless of lubricant. An increase in tissue shear occurred with either increased compression offset or increased surface roughness. This material and biomechanical test system allow control of cartilage sigma(xz,m) and E(xz,m), and hence, sliding magnitude, for an imposed lateral displacement. It therefore can facilitate study of cartilage mechanobiological responses to distinct regimes of cartilage loading and articulation, such as shear with variable amounts of sliding.


Assuntos
Cartilagem Articular/fisiologia , Modelos Biológicos , Líquido Sinovial/fisiologia , Animais , Bovinos , Força Compressiva/fisiologia , Simulação por Computador , Módulo de Elasticidade/fisiologia , Feminino , Dureza/fisiologia , Humanos , Lubrificação , Masculino , Pessoa de Meia-Idade , Resistência ao Cisalhamento/fisiologia , Estresse Mecânico , Propriedades de Superfície
10.
J Pharm Sci ; 99(2): 905-15, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19569202

RESUMO

The subdivision of scored tablets is an important problem for the exact individual therapy of patients. The recent guidelines of the EU require verification of the equal mass of the tablet halves, but this problem has previously never been investigated in papers published on the production technological aspects. Our aim was therefore to study the effects of the physicochemical properties of the raw materials and the effects of the compression process on the breaking parameters of the tablets. Artificial neural networks (ANNs) were applied for data analysis and modeling, which are very useful optimizing systems. The abilities of four different types of ANNs to predict the parameters of the compression process and the tablets were compared. The radial basis function and multilayer perceptron ANNs furnished statistically significant better results than linear or generalized regression neural networks. These ANN models revealed that the subdivision of scored tablets is strongly influenced by the production parameters and the compositions of the powder mixtures.


Assuntos
Composição de Medicamentos/métodos , Comprimidos , Algoritmos , Elasticidade , Excipientes , Testes de Dureza , Lubrificação , Modelos Teóricos , Redes Neurais de Computação , Organização e Administração , Tamanho da Partícula , Pós
11.
J Prosthet Dent ; 100(3): 183-93, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18762030

RESUMO

STATEMENT OF PROBLEM: Screw loosening is a problem for a percentage of implants. A probabilistic analysis to determine the cumulative probability distribution of the preload, the probability of obtaining an optimal preload, and the probabilistic sensitivities identifying important variables is lacking. PURPOSE: The purpose of this study was to examine the inherent variability of material properties, surface interactions, and applied torque in an implant system to determine the probability of obtaining desired preload values and to identify the significant variables that affect the preload. MATERIAL AND METHODS: Using software programs, an abutment screw was subjected to a tightening torque and the preload was determined from finite element (FE) analysis. The FE model was integrated with probabilistic analysis software. Two probabilistic analysis methods (advanced mean value and Monte Carlo sampling) were applied to determine the cumulative distribution function (CDF) of preload. The coefficient of friction, elastic moduli, Poisson's ratios, and applied torque were modeled as random variables and defined by probability distributions. Separate probability distributions were determined for the coefficient of friction in well-lubricated and dry environments. The probabilistic analyses were performed and the cumulative distribution of preload was determined for each environment. RESULTS: A distinct difference was seen between the preload probability distributions generated in a dry environment (normal distribution, mean (SD): 347 (61.9) N) compared to a well-lubricated environment (normal distribution, mean (SD): 616 (92.2) N). The probability of obtaining a preload value within the target range was approximately 54% for the well-lubricated environment and only 0.02% for the dry environment. The preload is predominately affected by the applied torque and coefficient of friction between the screw threads and implant bore at lower and middle values of the preload CDF, and by the applied torque and the elastic modulus of the abutment screw at high values of the preload CDF. CONCLUSIONS: Lubrication at the threaded surfaces between the abutment screw and implant bore affects the preload developed in the implant complex. For the well-lubricated surfaces, only approximately 50% of implants will have preload values within the generally accepted range. This probability can be improved by applying a higher torque than normally recommended or a more closely controlled torque than typically achieved. It is also suggested that materials with higher elastic moduli be used in the manufacture of the abutment screw to achieve a higher preload.


Assuntos
Dente Suporte , Implantes Dentários , Materiais Dentários/química , Planejamento de Prótese Dentária , Fenômenos Biomecânicos , Simulação por Computador , Dessecação , Elasticidade , Análise de Elementos Finitos , Fricção , Ligas de Ouro/química , Humanos , Lubrificação , Teste de Materiais , Modelos Biológicos , Método de Monte Carlo , Probabilidade , Estresse Mecânico , Propriedades de Superfície , Titânio/química , Torque
12.
Arch Oral Biol ; 53(11): 1011-6, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18603226

RESUMO

OBJECTIVE: Previous in vitro studies have described the wear characteristics of specimens in which enamel has been opposed to enamel and dentine opposed to dentine. The aim of this study was to assess the characteristics of wear between specimens in which enamel was opposed to dentine at loads simulating attrition and at pH values simulating different erosive environments. It was hypothesized that enamel would wear more slowly than dentine under all conditions. DESIGN: Opposing enamel and dentine specimens from 57 human third molar teeth were worn in electromechanical machines with various loads (32, 62 and 100 N) and lubricants (pH 1.2, 3.0 and 6.1). Tooth wear was quantified by measuring reduction in dentine volume over time using a 3D profilometer. Qualitative assessment was also carried out using scanning electron microscopy. RESULTS: Dentine wear increased with increasing load, and dentine wear was faster at pH 1.2 than at pH 3.0 or 6.1 for all loads tested. Interestingly, enamel wore more rapidly than dentine at pH 1.2 under all loads. At pH values of 3.0 and 6.1, enamel wear rates were not measurably different from zero and they were less than wear rates for opposing dentine specimens at all loads. Micrographic assessment showed extensive surface destruction of dentine wear facets due to erosion at pH 1.2. Dentine wear facets were smoother at pH 3.0 that at pH 6.1. CONCLUSIONS: When enamel wears against dentine in an acidic environment enamel will wear more rapidly at very low pH, while under less acid conditions dentine will wear faster than enamel.


Assuntos
Esmalte Dentário/patologia , Dentina/patologia , Atrito Dentário/patologia , Erosão Dentária/patologia , Esmalte Dentário/fisiopatologia , Dentina/fisiopatologia , Humanos , Concentração de Íons de Hidrogênio , Técnicas In Vitro , Lubrificação , Dente Serotino/patologia , Dente Serotino/fisiopatologia , Estresse Mecânico , Propriedades de Superfície , Atrito Dentário/fisiopatologia , Erosão Dentária/fisiopatologia
13.
Proc Inst Mech Eng H ; 222(3): 273-83, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18491697

RESUMO

New material combinations have been introduced as the bearing surfaces of hip prostheses in an attempt to prolong their life by overcoming the problems of failure due to wear-particle-induced osteolysis. This will hopefully reduce the need for revision surgery. The study detailed here used a hip simulator to assess the volumetric wear rates of large-diameter carbon-fibre-reinforced pitch-based poly(ether-ether-ketone) (CFR-PEEK) acetabular cups articulating against alumina femoral heads. The joints were tested for 25 x 10(6) cycles. Friction tests were also performed on these joints to determine the lubrication regime under which they operate. The average volumetric wear rate of the CFR-PEEK acetabular component of 54 mm diameter was 1.16 mm(3)/10(6) cycles, compared with 38.6 mm(3)/10(6) cycles for an ultra-high-molecular-weight polyethylene acetabular component of 28 mm diameter worn against a ceramic head. This extremely low wear rate was sustained over 25 x 10(6) cycles (the equivalent of up to approximately 25 years in vivo). The frictional studies showed that the joints worked under the mixed-boundary lubrication regime. The low wear produced by these joints showed that this novel joint couple offers low wear rates and therefore may be an alternative material choice for the reduction of osteolysis.


Assuntos
Acetábulo/patologia , Óxido de Alumínio/química , Cabeça do Fêmur/patologia , Prótese de Quadril , Cetonas/química , Polietilenoglicóis/química , Óxido de Alumínio/uso terapêutico , Benzofenonas , Materiais Biocompatíveis/química , Materiais Biocompatíveis/uso terapêutico , Carbono/uso terapêutico , Fibra de Carbono , Cerâmica/química , Cerâmica/uso terapêutico , Fricção , Prótese de Quadril/efeitos adversos , Humanos , Cetonas/uso terapêutico , Lubrificação , Teste de Materiais , Modelos Estruturais , Osteólise/etiologia , Osteólise/prevenção & controle , Polietilenoglicóis/uso terapêutico , Polietilenos/química , Polietilenos/uso terapêutico , Polímeros , Falha de Prótese , Propriedades de Superfície
14.
Environ Sci Technol ; 41(11): 4143-9, 2007 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-17612203

RESUMO

A comparative life cycle assessment examining soybean and petroleum-based lubricants is compiled using Monte Carlo analysis to assess system variability. Experimental data obtained from an aluminum manufacturing facility indicate significantly less soybean lubricant is required to achieve similar or superior performance. With improved performance and a lower use rate, a transition to soybean oil results in lower aggregate impacts of acidification, smog formation, and human health from criteria pollutants. Regardless of quantity consumed, soybean-based lubricants exhibit significant climate change and fossil fuel use benefits; however, eutrophication impacts are much greater due to non-point nutrient emissions. Fundamental tradeoffs in the carbon and nitrogen cycles are addressed in the analysis, demonstrating that a transition to soybean oil may result in climate change benefits at the expense of regional water quality.


Assuntos
Glycine max/química , Petróleo/análise , Alumínio , Conservação dos Recursos Naturais , Indústrias , Lubrificação , Método de Monte Carlo
16.
J Environ Manage ; 85(1): 198-203, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17110017

RESUMO

Major benefit uncertainties prevent monetary quantification of some environmental amenities. Replacing mineral lubricants with biodegradable substitutes is shown to be a case in point. However, it is possible to rank the social benefits of substituting mineral lubricants with regard to different applications and environments. As the private costs and benefits of substitution are mainly constant, only a policy that prioritizes full substitution in the applications with the greatest benefits can be efficient. It is shown that regulations requiring substitution in certain fields are likely to fulfil this criterion, while subsidies for production, processing, market introduction and research usually fail to meet the efficiency criterion.


Assuntos
Meio Ambiente , Lubrificação , Biodegradação Ambiental , Análise Custo-Benefício , Óleo Mineral , Óleos de Plantas , Incerteza
17.
J Environ Manage ; 85(1): 171-8, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17064840

RESUMO

The service life of lubricating oil produced in the United Arab Emirates (UAE) was examined using a car fueled with leaded or unleaded gasoline of the same grade in harsh local conditions. In addition, the economic impact of using leaded vs. unleaded gasoline via the effects on the useful life of engine oil was investigated. Every 500 km that the car was operated, the physical properties of the oil were examined to determine the optimum oil life before replacement. It was found that relative to unleaded gasoline, leaded gasoline resulted in a faster deterioration of lube oil properties and a reduced useful life of the oil. Many of the effects of use on the physical properties of oil became apparent from the beginning of its service, especially when leaded gasoline was used. Our findings indicate that the recommended useful life of oil when using leaded gasoline is 2500 km. With unleaded gasoline, deterioration of the physical properties of the lubricating oil became a concern after 3000 km. Thus with unleaded gasoline, it is recommended to have an oil change every 3500 km. These findings indicate that the decision of the UAE government to stop using lead compound additives to improve the octane number of gasoline will not only protect the environment from the harmful effects of lead compounds, but will also extend the useful life of oil. This extension will reduce the amount of used oil that is disposed of by up to 4678 tons/year. This reduction in oil use translates to a cost savings of about 23.4 million UAE Dirhams (=$6.37 million US Dollars) per year.


Assuntos
Gasolina , Chumbo , Petróleo/análise , Meio Ambiente , Poluição Ambiental/prevenção & controle , Umidade , Chumbo/análise , Lubrificação , Veículos Automotores , Temperatura , Emirados Árabes Unidos
19.
Am J Ophthalmol ; 139(3): 498-503, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15767060

RESUMO

PURPOSE: To compare the prevalence of keratoconjunctivitis sicca (KCS) in a prospective cohort of 22,382 diabetic patients with that in the general population. DESIGN: Prospective, observational, cohort study. SETTING: A district of israel's largest health maintenance organization. STUDY POPULATION: We followed the electronic medical records of all patients in the district older than 50 years (159,634 patients) between January 1 and December 31, 2003. Of those, 22,382 (14.0%) had diabetes. OBSERVATION PROCEDURE: The proportion of ocular lubrication consumers was compared among diabetic and nondiabetic patients. All HbA1c laboratory tests performed by the diabetic patients were documented (41,910 tests), and glycemic control was correlated with the consumption of ocular lubrication. MAIN OUTCOME MEASURES: Ocular lubrication use by diabetic patients compared with the general population and the relationship between glycemic control and ocular lubrication use. RESULTS: After age and gender adjustment, a significantly higher percentage of diabetic patients (20.6%) received ocular lubrication, compared with nondiabetic patients (13.8%, P < .001). The difference was significant for all age groups and for both sexes (P < .001). A similar significant difference was prominent between diabetic and nondiabetic patients aged 60 to 89 years who were frequent users of ocular lubrication. Ocular lubrication consumption increased with poorer glycemic control (mean annual HbA1c levels). Multivariate analysis revealed this effect to be independent of age, sex, place of birth, or place of residence. CONCLUSIONS: KCS is significantly more common among diabetic patients. Poor glycemic control correlates with increased artificial tear use in diabetic patients.


Assuntos
Complicações do Diabetes/epidemiologia , Ceratoconjuntivite Seca/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Glicemia/análise , Estudos de Coortes , Complicações do Diabetes/diagnóstico , Prescrições de Medicamentos/estatística & dados numéricos , Feminino , Hemoglobinas Glicadas/análise , Sistemas Pré-Pagos de Saúde/estatística & dados numéricos , Humanos , Israel/epidemiologia , Ceratoconjuntivite Seca/tratamento farmacológico , Lubrificação , Masculino , Pessoa de Meia-Idade , Soluções Oftálmicas/uso terapêutico , Prevalência , Estudos Prospectivos , Sistema de Registros
20.
J Endourol ; 19(2): 163-6, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15798411

RESUMO

PURPOSE: To compare the pain induced by outpatient flexible cystoscopy in men having local lidocaine jelly application or plain lubricant. PATIENTS AND METHODS: We performed a randomized, double-blind study to compare the anesthetic effect of intraurethral 2% lidocaine gel (N = 45) and plain lubricant (N = 46) in men undergoing outpatient flexible cystoscopy. The age, prostate size, and examination time were similar in the two groups. Before cystoscopy, we filled the urethra with 20 mL of gel, which was held for 15 minutes. A 15.5F flexible cystoscope was then used for examination. A 10-point visual analog pain scale (1 = least to 10 = most painful) and a four-point pain grade (grade 1 = least to grade 4 = most painful) were used to measure the pain perception. The amount of postoperative analgesic used and willingness to adopt the same anesthesia for future cystoscopy were also recorded. RESULTS: The mean pain scores for the lidocaine and plain gel groups were 2.8 +/- 1.1 and 2.5 +/- 1.1, respectively (P = 0.06), while the pain grades for the lidocaine gel and plain gel groups were 1.6 +/- 0.6 and 1.8 +/- 0.7, respectively (P = 0.19). In both groups, many patients (42.2% in the lidocaine gel group and 37% in the plain lubricant group) felt the external sphincter and prostatic urethra were the most uncomfortable areas during cystoscopy. Postcystoscopic analgesics were requested by 12 of 45 patients in the lidocaine group, but only 6 of 46 of the plain-gel group (P = 0.103). When patients were asked if they would desire general anesthesia for better pain control in future examinations, five of the lidocaine group responded positively, while three of the plain-gel group said they would (P = 0.62). The cost of lidocaine gel is about thrice that of the plain gel. CONCLUSION: Using plain lubricant is cheaper and faster than applying lidocaine gel. The pain score, pain grade, postcystoscopic analgesic requirement, and anesthetics requested for the next cystoscopy were similar in the two groups. However, a larger investigation will be needed to achieve more significant statistical power.


Assuntos
Anestésicos Locais/uso terapêutico , Clorexidina/análogos & derivados , Cistoscopia , Lidocaína/uso terapêutico , Dor/prevenção & controle , Idoso , Assistência Ambulatorial , Anestésicos Locais/economia , Anti-Infecciosos Locais/uso terapêutico , Clorexidina/uso terapêutico , Método Duplo-Cego , Géis , Humanos , Lidocaína/economia , Lubrificação , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Medição da Dor
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