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1.
Chemosphere ; 288(Pt 1): 132444, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34626658

RESUMO

Volatile fatty acids (VFAs) are the building blocks of the chemical industry, and they are the primary contributors to the planet's organic carbon cycle. VFA production from fossil fuels (mostly petroleum) is unsustainable, pollutes the environment, and generates greenhouse gases. As a result of these issues, there is a pressing need to develop alternate sources for the long-term generation of VFAs via anaerobic digestion. The accessible feedstocks for its sustainable production, as well as the influencing parameters, are discussed in this review. The use of VFAs as a raw material to make a variety of consumer products is reviewed in order to find a solution. It also bridges the gap between traditional and advanced VFA production and utilization methods from a variety of solid and liquid waste sources for economical stability.


Assuntos
Ácidos Graxos Voláteis , Gases de Efeito Estufa , Anaerobiose , Reatores Biológicos , Fermentação , Concentração de Íons de Hidrogênio
2.
Dis Esophagus ; 30(5): 1-5, 2017 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-28375446

RESUMO

Health-related quality of life (QOL) in children is not just related to physical symptoms but also how a disease impacts them psychosocially-mental, emotional, behavioral, and school functioning, all of which contribute to the growth and development of a child. A chronic disease, such as gastroesophageal reflux disease (GERD) characterized by troublesome symptoms and complications, can significantly impair a child's QOL. This makes it vital that treatment options aim at addressing this. Fundoplication, the surgical treatment for GERD, is one of the most common upper gastrointestinal surgeries performed by pediatric surgeons. As with any medical treatment, there is an inherent need to determine the efficacy of the procedure not only in terms of objective physiologic measures but also QOL measures for both the children and parents. There are currently limited and inconsistent data on QOL outcomes postfundoplication in children with GERD. This literature review aims at critically analyzing the data by comparing current trends with research and identifying gaps in evidence to justify the need for further research within the field.


Assuntos
Fundoplicatura/psicologia , Refluxo Gastroesofágico/psicologia , Refluxo Gastroesofágico/cirurgia , Qualidade de Vida , Adolescente , Criança , Pré-Escolar , Feminino , Fundoplicatura/métodos , Humanos , Lactente , Recém-Nascido , Masculino , Período Pós-Operatório , Resultado do Tratamento
3.
Adv Biomed Res ; 3: 101, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24800190

RESUMO

BACKGROUND: Fragile fractures are most likely manifestations of fatigue damage that develop under repetitive loading conditions. Numerous microcracks disperse throughout the bone with the tensile and compressive loads. In this study, tensile and compressive load tests are performed on specimens of both the genders within 19 to 83 years of age and the failure strength is estimated. MATERIALS AND METHODS: Fifty five human femur cortical samples are tested. They are divided into various age groups ranging from 19-83 years. Mechanical tests are performed on an Instron 3366 universal testing machine, according to American Society for Testing and Materials International (ASTM) standards. RESULTS: The results show that stress induced in the bone tissue depends on age and gender. It is observed that both tensile and compression strengths reduces as age advances. Compressive strength is more than tensile strength in both the genders. CONCLUSION: The compression and tensile strength of human femur cortical bone is estimated for both male and female subjecting in the age group of 19-83 years. The fracture toughness increases till 35 years in male and 30 years in female and reduces there after. Mechanical properties of bone are age and gender dependent.

4.
Free Radic Res ; 48(7): 740-8, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24628396

RESUMO

BACKGROUND: Because patients with cystic fibrosis (CF) are living longer, chronic malabsorption of carotenoids associated with CF resulting in decreased macular pigment (MP) may affect macular long-term health in later-life pathology. This study compared the macular pigment optical density (MPOD) and corresponding central macular volume (MV) of adult CF subjects and age-matched normal controls subjects to determine whether chronic malabsorption associated with CF could adversely affect macular photoreceptor anatomy. OBJECTIVE: Our aim was to compare MPOD with measurements of central MV in CF patients with age-matched controls. Design. In nine adult CF patients (ages: 29-46) without a history of carotenoid supplementation or known retinal or optic nerve disease MPOD and MV were measured by heterochromatic flicker photometry (HFP) and optical coherence tomography (OCT), respectively, and compared to results obtained from 14 age-matched controls. RESULTS: MPOD was significantly reduced at 15' and 30' eccentricities in CF subjects compared to normal subjects (mean difference -0.21 at 15', -0.25 at 30', p < 0.005). No significant difference, in MV noted at any of the eccentricities tested between CF and normal subjects (CF: normal MV ratios ranged from 0.94 to 1.1 for all eccentricities with p > 0.1 at all eccentricities). Best corrected vision acuity and fundus examination were normal in all subjects. CONCLUSIONS: Unsupplemented CF patients have markedly lower levels of macular carotenoids (e.g., lutein and zeaxanthin), but well-maintained visual function and no significant reductions in central MV primarily composed of macular photoreceptors. Future studies are needed to determine whether the lifelong decrease in protective central retinal carotenoids predisposes CF patients to later-life retinal pathology.


Assuntos
Fibrose Cística/complicações , Fibrose Cística/patologia , Macula Lutea/metabolismo , Pigmento Macular/metabolismo , Doenças Retinianas/metabolismo , Doenças Retinianas/patologia , Adulto , Fibrose Cística/metabolismo , Feminino , Humanos , Macula Lutea/patologia , Masculino , Pessoa de Meia-Idade , Doenças Retinianas/complicações
6.
Eye (Lond) ; 27(3): 438-42, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23288135

RESUMO

PURPOSE: To describe the results of photodynamic therapy (PDT) for juxtapapillary and peripheral retinal capillary hemangioma (RCH). PATIENTS AND METHODS: Interventional case series of four eyes (four patients) with juxtapapillary RCH and one eye (one patient) with peripheral RCH. Two eyes with juxtapapillary RCH had received two sessions of full-fluence, double-duration PDT; whereas other two eyes had received single session of half-fluence, single-duration PDT. The peripheral RCH was treated with a single session of full-fluence, single-duration PDT. RESULTS: Two patients had von Hippel-Lindau disease. Follow-up duration ranged from 4 months to 1 year. Pre-PDT visual acuity (VA) ranged from 20/200 to HM (juxtapapillary RCH) and 20/100 (peripheral RCH). Among the eyes with juxtapapillary RCH, tumor regression with partial resolution of macular edema was noted in two eyes (one eye each with half-fluence and full-fluence PDT), whereas two eyes had no change in tumor size with persistent macular edema. VA remained stable in three eyes and declined in one eye. In an eye with peripheral RCH, regression of tumor and macular edema with VA improvement was noted. Post-PDT complications included epiretinal membrane (one eye) and transient exudative retinal detachment (one eye). CONCLUSION: PDT can be effective in reducing macular edema associated with RCH but this does not always correspond with an improvement in VA especially for juxtapapillary tumors.


Assuntos
Hemangioma Capilar/tratamento farmacológico , Fotoquimioterapia , Fármacos Fotossensibilizantes/uso terapêutico , Porfirinas/uso terapêutico , Neoplasias da Retina/tratamento farmacológico , Adulto , Feminino , Hemangioma Capilar/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias da Retina/patologia , Tomografia de Coerência Óptica , Resultado do Tratamento , Verteporfina , Acuidade Visual/fisiologia , Adulto Jovem , Doença de von Hippel-Lindau/complicações
7.
Eye (Lond) ; 25(6): 775-83, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21436847

RESUMO

PURPOSE: The purpose of this study is to evaluate the macular morphological changes associated with idiopathic epiretinal membrane (iERM) using high-resolution Fourier-domain optical coherence tomography (FD-OCT), as they correlate with visual acuity and microperimetry (MP-1). METHODS: In all, 24 eyes (19 subjects) with iERM were imaged prospectively using FD-OCT with axial resolution of 4.5 µm and transverse resolution of 10 to 15 µm. MP-1 and Stratus OCT were carried out in a subset of eyes. RESULTS: The mean log of the minimum angle of resolution best-corrected visual acuity (BCVA) was 0.18±0.16 (range: -0.08 to 0.48, Snellen equivalent 20/15(-1) to 20/60). ERM was visualized in all 24 eyes with FD-OCT and in 17 eyes (85%) of 20 eyes imaged with Stratus OCT. Although BCVA correlated with macular thickening in the central 1 mm sub-field of the Stratus ETDRS (P=0.0005) and macular volume (central 3 mm area) on FD-OCT (P<0.0001), macular thickening on thickness map and volume correlated poorly with decrease in macular sensitivity on MP-1 (P=0.16). On FD-OCT, foveal morphological changes correlated best with decrease in BCVA, the strongest being central foveal thickness (P<0.0001). Other significant changes included blurring of the foveal inner segment-outer segment (IS-OS) junction and/or Verhoeff's membrane, vitreal displacement of foveal outer nuclear layer and foveal detachment (P<0.05). Foveal IS-OS junction disruption was seen in 25% of eyes on Stratus OCT but in none of the eyes on FD-OCT. CONCLUSION: FD-OCT allowed improved visualization of ERM and associated foveal morphological changes that correlated best with BCVA. Macular thickening correlated weakly with decreased macular function as assessed by MP-1.


Assuntos
Membrana Epirretiniana/fisiopatologia , Macula Lutea/patologia , Acuidade Visual/fisiologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Análise de Fourier , Humanos , Macula Lutea/fisiopatologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Tomografia de Coerência Óptica/métodos , Campos Visuais/fisiologia
8.
Int J Obes (Lond) ; 34(4): 614-23, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19949415

RESUMO

CONTEXT: Although recent trends in obesity have been well documented, generational patterns of obesity from early childhood through adulthood across birth cohorts, which account for the recent epidemic of childhood obesity, have not been well described. Such trends may have implications for the prevalence of obesity-associated conditions among population subgroups, including type 2 diabetes. OBJECTIVE: Our objective was to evaluate trajectories of obesity over the life course for the US population, overall and by gender and race. DESIGN, SETTING AND PARTICIPANTS: We conducted an age, period and birth cohort analysis of obesity for US individuals who participated in the National Health and Nutrition Examination Surveys (NHANES) (1971-2006). MAIN OUTCOME MEASURES: Obesity was defined as a body mass index >or=95th percentile for individuals aged 2-16 years or >or=30 kg m(-2) among individuals older than 16 years. Age was represented by the age of the individual at each NHANES, period was defined by the year midpoint of each survey, and cohort was calculated by subtracting age from period. RESULTS: Recent birth cohorts are becoming obese in greater proportions for a given age, and are experiencing a greater duration of obesity over their lifetime. For example, although the 1966-1975 and 1976-1985 birth cohorts had reached an estimated obesity prevalence of at least 20% by 20-29 years of age, this level was only reached by 30-39 years for the 1946-1955 and 1956-1965 birth cohorts, by 40-49 years for the 1936-1945 birth cohort and by 50-59 years of age for the 1926-1935 birth cohort. Trends are particularly pronounced for female compared with male, and black compared with white cohorts. CONCLUSIONS: The increasing cumulative exposure to excess weight over the lifetime of recent birth cohorts will likely have profound implications for future rates of type 2 diabetes, and mortality within the US population.


Assuntos
Diabetes Mellitus Tipo 2/epidemiologia , Obesidade/epidemiologia , Adolescente , Fatores Etários , Índice de Massa Corporal , Peso Corporal/fisiologia , Criança , Pré-Escolar , Estudos de Coortes , Diabetes Mellitus Tipo 2/etiologia , Diabetes Mellitus Tipo 2/fisiopatologia , Feminino , Humanos , Expectativa de Vida/tendências , Masculino , Modelos Estatísticos , Obesidade/complicações , Obesidade/fisiopatologia , Prevalência , Estados Unidos/epidemiologia
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