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1.
Int J Mol Sci ; 22(21)2021 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-34769201

RESUMO

Aging usually comes associated with increased visceral fat accumulation, reaching even an obesity state, and favoring its associated comorbidities. One of the processes involved in aging is cellular senescence, which is highly dependent on the activity of the regulators of the cell cycle. The aim of this study was to analyze the changes in the expression of p27 and cdk2 in different adipose tissue depots during aging, as well as their regulation by obesity in mice. Changes in the expression of p27 and CDK2 in visceral and subcutaneous white adipose tissue (WAT) biopsies were also analyzed in a human cohort of obesity and type 2 diabetes. p27, but not cdk2, exhibits a lower expression in subcutaneous than in visceral WAT in mice and humans. p27 is drastically downregulated by aging in subcutaneous WAT (scWAT), but not in gonadal WAT, of female mice. Obesity upregulates p27 and cdk2 expression in scWAT, but not in other fat depots of aged mice. In humans, a significant upregulation of p27 was observed in visceral WAT of subjects with obesity. Taken together, these results show a differential adipose depot-dependent regulation of p27 and cdk2 in aging and obesity, suggesting that p27 and cdk2 could contribute to the adipose-tissue depot's metabolic differences. Further studies are necessary to fully corroborate this hypothesis.


Assuntos
Tecido Adiposo Branco/metabolismo , Envelhecimento/metabolismo , Quinase 2 Dependente de Ciclina/metabolismo , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Obesidade/metabolismo , Animais , Feminino , Camundongos
2.
Radiographics ; 37(1): 323-345, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28076010

RESUMO

Foreign-body (FB) ingestion is less common in adults than in children, but still occurs. Diagnostic management of patients with suspected FB ingestion in emergency departments depends on FB type and location, both of which are related to the patient profile. In adults, fish and chicken bones are the most common FB types, and the oropharynx and cricopharyngeal muscle are the most common locations. Once accidentally swallowed, an FB may become lodged in the oropharynx, and in such cases indirect or fiberoptic laryngoscopy is the first clinical management option. For FBs that have passed beyond this location, radiologic study is recommended, including anteroposterior and lateral neck radiographs (LNRs) using the soft-tissue technique. This is a quick and simple imaging method that in emergency departments achieves detection rates of 70%-80% in assessing FBs in the hypopharynx and upper cervical esophagus. Careful initial evaluation using LNRs can determine the presence and nature of an FB, which helps with predicting the location and risk assessment, making further imaging-including computed tomography-unnecessary. Prevertebral soft-tissue swelling is a nonspecific indirect sign, which in the appropriate clinical context raises suspicion of a radiolucent FB or related complications. LNRs can sometimes be difficult to interpret due to the presence of multiple overlapping soft-tissue structures and variable patterns of laryngeal cartilage calcification in adults. Adequate performance in interpreting LNRs along with familiarity with the full diagnostic process in these patients will enable radiologists to use the right imaging technique for the right patient, as described in the clinical algorithm proposed by the authors. ©RSNA, 2017.


Assuntos
Bezoares/diagnóstico por imagem , Erros de Diagnóstico/prevenção & controle , Lesões do Pescoço/diagnóstico por imagem , Posicionamento do Paciente/métodos , Intensificação de Imagem Radiográfica/métodos , Lesões dos Tecidos Moles/diagnóstico por imagem , Adulto , Artefatos , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
3.
J Refract Surg ; 31(4): 230-5, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25884577

RESUMO

PURPOSE: To evaluate the effect of pupil size on image quality of a sectorial multifocal intraocular lens (IOL), the Lentis Mplus (Oculentis GmbH, Berlin, Germany), and the Acri.LISA IOL (Carl Zeiss Meditec, Jena, Germany). METHODS: The authors measured the MTFs of the Lentis Mplus LS-312 IOL and the Acri.LISA 366D IOL with three different sizes of pupil diameters: 3, 4, and 5 mm. The MTF was calculated from the cross-line spread function recorded with the OPAL Vector System (Image Science Ltd., Oxford, UK) by using fast Fourier-transform techniques. RESULTS: In distance focus, the image quality provided by the Lentis Mplus IOL was better than that of the Acri. LISA IOL with all pupil diameters. In near focus, the MTF of the Acri.LISA IOL was better with a 3-mm pupil, but poor with larger pupils. The aberration effect was equal in both IOLs in distance focus, but in near focus and with a 3-mm pupil, the Acri.LISA IOL was less affected by the aberration than the Lentis Mplus IOL. CONCLUSION: The Lentis Mplus IOL provides better distance image quality than the Acri.LISA IOL, whereas the near image quality of the Acri.LISA IOL is better with small-pupil diameter. The sectorial design makes this IOL more suitable for patients with a pupil diameter greater than 3 mm.


Assuntos
Lentes Intraoculares , Óptica e Fotônica , Pupila/fisiologia , Análise de Fourier , Humanos , Modelos Teóricos
4.
Radiographics ; 33(5): 1453-70, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24025935

RESUMO

Acute gastrointestinal bleeding is a common reason for emergency department admissions and an important cause of morbidity and mortality. Factors that complicate its clinical management include patient debility due to comorbidities; intermittence of hemorrhage; and multiple sites of simultaneous bleeding. Its management, therefore, must be multidisciplinary and include emergency physicians, gastroenterologists, and surgeons, as well as radiologists for diagnostic imaging and interventional therapy. Upper gastrointestinal tract bleeding is usually managed endoscopically, with radiologic intervention reserved as an alternative to be used if endoscopic therapy fails. Endoscopy is often less successful in the management of acute lower gastrointestinal tract bleeding, where colonoscopy may be more effective. The merits of performing bowel cleansing before colonoscopy in such cases might be offset by the resultant increase in response time and should be weighed carefully against the deficits in visualization and diagnostic accuracy that would result from performing colonoscopy without bowel preparation. In recent years, multidetector computed tomographic (CT) angiography has gained acceptance as a first-line option for the diagnosis and management of lower gastrointestinal tract bleeding. In selected cases of upper gastrointestinal tract bleeding, CT angiography also provides accurate information about the presence or absence of active bleeding, its source, and its cause. This information helps shorten the total diagnostic time and minimizes or eliminates the need for more expensive and more invasive procedures.


Assuntos
Angiografia/métodos , Cuidados Críticos/métodos , Hemorragia Gastrointestinal/diagnóstico por imagem , Hemorragia Gastrointestinal/prevenção & controle , Tomografia Computadorizada Multidetectores/métodos , Intensificação de Imagem Radiográfica/métodos , Doença Aguda , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
5.
Radiology ; 262(1): 109-16, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22084211

RESUMO

PURPOSE: To assess the diagnostic performance of computed tomographic (CT) angiography as the initial diagnostic examination for patients presenting to the emergency room with acute lower intestinal bleeding. MATERIALS AND METHODS: The study was reviewed and approved by the ethics committee, and written informed consent was obtained from each patient or their closest relative when the clinical condition precluded consent by the patient. This prospective study comprised 47 patients (27 men, 20 women; mean age, 68 years) with acute lower gastrointestinal tract bleeding who were referred to undergo emergency colonoscopy for evaluation. CT angiography was performed in all patients shortly after arrival to the emergency room. Findings identified at CT angiography included active extravasation (ongoing hemorrhage) or hyperattenuating intraluminal contents on noncontrast material-enhanced images (recent hemorrhage). Presence and location of bleeding and likely cause of hemorrhage were determined and compared with the standard of reference (angiography, colonoscopy, or surgical findings). Data collected were analyzed with a statistical software package. Sensitivity, specificity, and positive and negative predictive values of CT angiography in depicting ongoing or recent hemorrhage were calculated and compared with those of standard of reference. RESULTS: CT angiography demonstrated active bleeding in 14 patients and intraluminal hyperattenuating material in six patients. The sensitivity, specificity, positive predictive value, and negative predictive value of CT angiography in depicting active or recent bleeding were 100% (19 of 19), 96% (27 of 28), 95% (19 of 20), and 100% (27 of 27), respectively. Findings of CT angiography and the standard of reference were concordant for determining definite or potential cause of bleeding in 44 of 47 patients (93% accuracy). CONCLUSION: CT angiography performed in the emergency setting in patients with acute lower intestinal bleeding is feasible and correctly depicts the presence and location of active or recent hemorrhage, as well as the potential cause, in the majority of patients.


Assuntos
Angiografia/métodos , Hemorragia Gastrointestinal/diagnóstico por imagem , Trato Gastrointestinal Inferior/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Doença Aguda , Idoso , Colonoscopia , Meios de Contraste , Extravasamento de Materiais Terapêuticos e Diagnósticos , Feminino , Humanos , Masculino , Valor Preditivo dos Testes , Estudos Prospectivos , Interpretação de Imagem Radiográfica Assistida por Computador , Sensibilidade e Especificidade , Ácidos Tri-Iodobenzoicos
6.
J Refract Surg ; 28(5): 335-40, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22443805

RESUMO

PURPOSE: To evaluate the changes in optical quality when toric intraocular lenses (IOL) are rotated or tilted and to demonstrate that IOL rotation produces an increasing effect of aberrations. METHODS: Modulation transfer function (MTF) and average modulation were used to analyze the image quality of a toric IOL. The axis of the toric IOL was rotated 5°, 10°, 15°, 20°, 25°, and 30° in successive MTF measurements. The tilt values were 0° to 5°, in increments of 1°, plus a tilt of 15°. Pupil diameters of 3 and 5 mm were used. RESULTS: The MTF decay due to aberrations was more sensitive to rotation than tilt. The main decrement in the average modulation, of approximately 50% in both pupils, occurs when the IOL rotates from 0° to 5°. Between 0° and 1° tilt, the average modulation decreases approximately 25% for both pupils; with tilt >1°, the average modulation remains virtually unchanged. The points representing average modulation versus rotation angle are satisfactorily fitted by an exponential function, R=0.98. Average modulation versus tilt angle provides lower correlation degrees, R=0.91 and R=0.79, for 3- and 5-mm pupils, respectively. CONCLUSIONS: The MTF of the toric IOL decays with rotation and tilt, with greater decrement occurring in rotation from 0° to 5°. An asymptotic value exists in the average modulation decay, meaning that for angles higher than 15°, the average modulation of the toric IOL remains virtually constant.


Assuntos
Migração do Implante de Lente Intraocular/complicações , Lentes Intraoculares , Modelos Teóricos , Óptica e Fotônica , Rotação , Aberrações de Frente de Onda da Córnea/etiologia , Humanos
7.
Ophthalmology ; 118(1): 3-8, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20801517

RESUMO

PURPOSE: To compare the spectral transmission of different intraocular lenses (IOLs) with either ultraviolet (UV) or blue-light filters, and to analyze the performance of these filters with artificial light sources as well as sunlight. DESIGN: Experimental study. METHODS: The spectral transmission curve of 10 IOLs was measured using a PerkinElmer Lambda 800 UV/VIS spectrometer (Waltham, MA). Different filtering simulations were performed using the D65 standard illuminant as daylight and standard incandescent lamp and fluorescent bulb illuminants. MAIN OUTCOMES MEASURES: Spectral transmittance of the IOLs. RESULTS: All the IOLs studied provide good UVC (200-280 nm) and UVB (280-315 nm) protection, except for one that presented an appreciable window at 270 nm. Nevertheless, both natural and artificial sources have practically no emission under 300 nm. In the UVA (315-380 nm) range the curves of the different IOLs manifested different degrees of absorption. CONCLUSIONS: Not all the UV filters incorporated in different IOLs protect equally. The filters that provide greater photoprotection against UV radiation, even blue light, are yellow and orange. Then, yellow and orange IOL filters may be best suited for cases requiring special retinal protection. The filters that favor better photoreception of visible light (380-780 nm) are those that transmit this radiation close to 100%. Artificial illumination practically does not emit in the UV range, but its levels of illumination are very low when compared with solar light. A possible balance between photoprotection and photoreception could be a sharp cutoff filter with the cutoff wavelength near 400 nm and a maximum transmittance around 100%.


Assuntos
Lentes Intraoculares , Luz , Iluminação , Análise Espectral , Filtração , Fluorescência , Incandescência , Luz Solar , Raios Ultravioleta
8.
Eur J Ophthalmol ; 20(1): 71-5, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-19882520

RESUMO

PURPOSE: The imaging quality provided by a piggyback integrated by a monofocal intraocular lens (IOL) + a bifocal IOL of zero power and +3.75 diopters of addition is compared with the optics quality of a simple multifocal IOL of the same power and addition. METHODS: The imaging quality was evaluated by determining the modulation transfer function (MTF), using an artificial eye simulating in vivo conditions of the anterior chamber, including an artificial cornea and a wet cell containing physiologic solution where the IOL was positioned. The MTFs of the bifocal piggyback for near and distance vision were measured, with pupil diameters of 3 and 5 mm, and compared with the MTFs of an equivalent power of ReSTOR and TECNIS multifocal IOLs measured under the same conditions. RESULTS: The MTFs for distance and near focus of the bifocal piggyback are similar to the MTFs of the ReSTOR and TECNIS multifocal IOLs with the two diameters of pupil. A more accurate comparison, values of average modulation, and Strehl ratio show a greater similitude with ReSTOR than with TECNIS. CONCLUSIONS: The bifocal piggyback system provides a similar imaging quality to that obtained with a ReSTOR multifocal IOL and, like the ReSTOR, provides better performance in distance vision than in near vision, whereas the TECNIS multifocal IOL provides the best performance.


Assuntos
Lentes Intraoculares , Modelos Teóricos , Óptica e Fotônica , Órgãos Artificiais , Percepção de Profundidade/fisiologia , Olho , Humanos , Refração Ocular/fisiologia , Acuidade Visual/fisiologia
9.
Arq Bras Oftalmol ; 82(1): 56-61, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30652767

RESUMO

PURPOSE: The porcine eye is frequently used as a research model. This paper analyzes the effect of different storage methods on the transparency of pig crystalline lens. METHODS: A spectral transmission curve (from 220 to 780 nm) for the crystalline lens was determined experimentally after storage in different conditions: saline solution, formalin, castor oil, and freezing at -80°C. The total transmission in the visible spectrum, which was used as an index of transparency, was calculated from these curves. For comparative purposes, fresh lenses were evaluated and used as controls. RESULTS: Storing the porcine crystalline lens in saline solution or castor oil resulted in a transparency loss of approximately 10% after 24 h and storage in formalin resulted in a loss of nearly 30%. Storage by freezing at -80°C for 4 weeks maintained the transparency of the crystalline lens; the spectral transmission measured immediately after defrosting at room temperature coincided exactly with that of the freshly extracted lens. CONCLUSIONS: The transparency of porcine crystalline lens is affected by the storage method. The visible spectrum is the most affected, evidenced by the effect on the transparency and consequently the amount of light transmitted. The results show that freezing at -80°C maintains the transpa rency of the crystalline lens for at least 4 weeks.


Assuntos
Cristalino/anatomia & histologia , Preservação de Órgãos/métodos , Animais , Óleo de Rícino/química , Formaldeído/química , Congelamento , Cristalino/diagnóstico por imagem , Cristalino/fisiologia , Luz , Modelos Animais , Valores de Referência , Reprodutibilidade dos Testes , Espectrofotometria/instrumentação , Espectrofotometria/métodos , Suínos , Fatores de Tempo , Raios Ultravioleta
10.
J Cataract Refract Surg ; 34(9): 1571-7, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18721722

RESUMO

PURPOSE: To evaluate the efficacy of a standard double intraocular lens (IOL) system (IOL-Vip) in patients with low vision and central scotoma due to macular degeneration and assess the predictability of the residual refraction and magnification. SETTING: Ophthalmology Department, Hospital General Universitario, Valencia, Spain. METHODS: This interventional prospective noncomparative case series comprised 13 consecutive surgical procedures in 10 patients with central scotoma. Follow-up was 12 months. Evaluation included the difference between preoperative and postoperative best corrected visual acuity (BCVA), refraction, position of the IOLs, endothelial cell density, and occurrence of postoperative complications. Residual refraction and eye magnification were calculated using a theory developed in a previous study, and the values were compared with the clinical results. RESULTS: The mean BCVA was 1.37 logMAR preoperatively and 0.68 logMAR 1 year postoperatively. The mean best corrected clinical gain was 44%. There was no statistically significant difference between the clinically evaluated and theoretically calculated residual refractions (P = .17). No intraoperative or postoperative complications occurred. CONCLUSIONS: Implantation of the double IOL system improved BCVA in patients with low vision due to advanced maculopathy. The results were best in myopic patients (long eyes); patients with hyperopia (short eyes) had high residual refraction. The postoperative clinical gain and residual refraction were predictable, showing the feasibility of implanting a customized double IOL.


Assuntos
Implante de Lente Intraocular , Lentes Intraoculares , Degeneração Macular/complicações , Refração Ocular/fisiologia , Escotoma/fisiopatologia , Baixa Visão/fisiopatologia , Acuidade Visual/fisiologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Facoemulsificação , Estudos Prospectivos , Escotoma/etiologia , Resultado do Tratamento , Baixa Visão/etiologia
11.
J Cataract Refract Surg ; 33(10): 1781-9, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17889777

RESUMO

PURPOSE: To analyze the effect of different optical parameters of the eye on the outcomes of implantation of a double intraocular lens (IOL) magnification device in patients with low vision. SETTING: Fundación Oftalmológica del Mediterráneo, Valencia, Spain. METHODS: The eye's refraction and magnification before and after surgery were evaluated using a theoretical eye model based on paraxial optics approximation. Four parameters on which refraction and magnification are dependent were evaluated: anterior chamber depth (ACD), axial length (AL), mean keratometry (Km), and the distance between the 2 implanted IOLs. The 4 variables were analyzed separately in the first stage. Next, different combinations of ACD, AL, and Km values were studied. The goal was to predict what type of eye (in terms of ACD, AL, and Km values) is suitable for successful implantation of the double-IOL magnification device. RESULTS: Axial length had a significant influence on eye magnification. The Km value mainly affected refraction. The ACD did not influence the success of the procedure. The distance between the 2 IOLs was a decisive parameter in the analysis. CONCLUSIONS: Analysis of optical and biometric eye parameters could guide selection of patients for implantation of the double-IOL magnification device. Eyes with higher AL and Km values (myopic eyes) are the most suitable for this procedure.


Assuntos
Implante de Lente Intraocular , Lentes Intraoculares , Óptica e Fotônica , Refração Ocular/fisiologia , Baixa Visão/fisiopatologia , Câmara Anterior/anatomia & histologia , Biometria , Olho/anatomia & histologia , Humanos , Hiperopia/fisiopatologia , Hiperopia/cirurgia , Modelos Teóricos , Miopia/fisiopatologia , Miopia/cirurgia , Resultado do Tratamento , Baixa Visão/reabilitação
12.
J Cataract Refract Surg ; 33(12): 2111-7, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18053913

RESUMO

PURPOSE: To analyze the image quality with a refractive and 2 hybrid refractive-diffractive multifocal intraocular lenses (IOLs) in vitro to determine the IOL modulation transfer function (MTF) following the EN-ISO international standard for distance and near vision and to study the IOLs' behavior with different pupil sizes. SETTING: Fundación Oftalmológica del Mediterráneo, Valencia, Spain. METHODS: This study evaluated 4 IOLs: the hybrid refractive-diffractive AcrySof ReSTOR SN60D3 (Alcon) and Tecnis ZM900 (AMO), the refractive ReZoom NXG (AMO), and the monofocal AcrySof SN60WF (Alcon). The MTF was calculated from the cross-line spread function recorded with the OPAL Vector System (Image Science Ltd.) using fast Fourier transform techniques. The artificial eye model simulated in vivo conditions of the anterior chamber and included an artificial cornea and physiological solution, in which the IOLs were positioned. The pupil sizes varied between 2.0 mm and 5.0 mm in steps of 0.5 mm. RESULTS: For distance vision and small pupils (2.0 to 3.5 mm), the refractive IOL provided better image quality than the 2 hybrid IOLs. When the pupil was larger, the distance vision was similar with all IOLs. The 2 hybrid IOLs gave better image quality than the refractive IOL for near vision with any pupil size. With the refractive IOL and pupils smaller than 3.5 mm, near focusing did not occur, resulting in poor image quality. Of the hybrid IOLs, the AcrySof ReSTOR SN60D3 provided better distance image quality and the Tecnis ZM900 provided better near image quality. CONCLUSIONS: The refractive IOL gave better image quality than the hybrid IOLs at distance and with small pupils. With pupils larger than 3.5 mm, the quality was similar. Hybrid IOLs gave significantly better image quality for near vision with all pupil sizes. AcrySof ReSTOR SN60D3 IOLs give better distance vision than Tecnis ZM900 IOLs; the latter gave better near vision. The reference monofocal IOL provided better distance images than any multifocal IOL with all pupil sizes.


Assuntos
Sensibilidades de Contraste/fisiologia , Lentes Intraoculares , Desenho de Prótese , Pupila/fisiologia , Análise de Fourier , Humanos , Modelos Biológicos , Óptica e Fotônica
13.
Biomed Opt Express ; 8(10): 4621-4628, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-29082089

RESUMO

To study the optical changes on hydrogel-silicone intraocular lenses (IOLs) resulting from loading them with dexamethasone. We used prototype hydrogel(pHEMA)-silicone IOLs and loaded the matrices with an anti-inflammatory drug (dexamethasone). The optical properties we analyzed experimentally were a) modulation transfer function (MTF); b) spectral transmission; c) diopter power. These determinations were performed on drug-loaded IOLs, IOLs that had released the drug, and IOLs that had not been drug-loaded. Loading a hydrogel-silicone IOL with dexamethasone results in impairment of its optical qualities, in particular its MTF and spectral transmission, but not dioptric power. However, once the drug has been released, it almost recovers its initial optical properties.

14.
Cont Lens Anterior Eye ; 39(2): 141-7, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26483287

RESUMO

PURPOSE: To determine the spectral transmission of contact lenses (CLs), with and without an ultraviolet (UV) filter to evaluate their capacity for protection under UV radiation from artificial illumination (incandescent, fluorescent, xenon (Xe) lamps, or white LEDs (light-emitting diode)). METHODS: The transmission curves of nine soft CLs were obtained by using a PerkinElmer Lambda 35 UV-vis spectrophotometer. A CIE standard was used for the emission spectra of incandescent and fluorescent lamps, and Xe lamps and white LEDs were measured by using an International Light Technologies ILT-950 spectroradiometer. RESULTS: Five of the nine soft CLs analysed state that they incorporate UV filters, but the other four do not specify anything in this regard. The spectral transmission of all the CLs studied is excellent in the visible region. The CLs with UV filters filter out this radiation more or less effectively. Xe lamps emit a part in the UV region. Incandescent, fluorescent and white LEDs do not emit at all in the UV. CONCLUSIONS: Incorporating UV filters is important when the illumination is from a Xe lamp since this light source emits in the UV region. This, however, does not occur with incandescent and fluorescent lamps or white LEDs. The CLs that do incorporate UV filters meet all the standard requirements that the U.S. FDA (Food and Drug Administration) has for UV-blocking CLs Class II (OcularScience, CooperVision and Neolens), and AcuvueMoist and HydronActifresh400 even comply with the stricter Class I. The CLs without UV filters let UVA, UVB and even some UVC through.


Assuntos
Absorção de Radiação , Lentes de Contato Hidrofílicas , Filtração/instrumentação , Luz , Proteção Radiológica/instrumentação , Análise Espectral , Raios Ultravioleta
16.
Maturitas ; 80(3): 288-95, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25577153

RESUMO

The aim of this work is to study the prevalence of osteoporotic vertebral fractures in Spanish women over 45 years of age, based on the selection of a nationwide sample. An observational, cross-sectional, multicenter study was conducted during 2006, in all of Spain's regions. The sample analyzed was of 5000 individuals, representative of the female population over age 45 in Spain. A questionnaire was used to determine which factors are most often associated with vertebral fractures. We also assessed whether the Prevalent Vertebral Fracture Index, proposed by Vogt, is useful in indicating a possible osteoporotic vertebral fracture. Five hundred orthopedic surgeons, from various Spanish regions, were trained in different aspects of the study: inclusion and exclusion criteria, management of the risk factor questionnaire, and implementation of the Vogt questionnaire. The number of fracture cases was 1549 (31.79%). 528 Women (34.08%) had a single vertebral fracture, and 1021 (65.92%) had multiple vertebral fractures. The following factors were statistically significantly associated with vertebral fracture: age, late menarche, early menopause, diabetes mellitus, hyperparathyroidism, rheumatoid arthritis, height loss, daily physical activity, corticosteroid therapy, personal history of osteoporotic fracture and previous diagnosis of osteoporosis. The differences in Vogt score according to age and fracture status were statistically significant. The conclusion of the study is that vertebral osteoporotic fracture in the female Spanish population is frequent. The high prevalence in the Spanish population older than 60 years is probably related to malnutrition in the period from 1936 to 1952.


Assuntos
Vértebras Lombares/lesões , Fraturas por Osteoporose/epidemiologia , Fraturas da Coluna Vertebral/epidemiologia , Vértebras Torácicas/lesões , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Menarca , Pessoa de Meia-Idade , Fraturas por Osteoporose/etiologia , Prevalência , Fatores de Risco , Espanha/epidemiologia , Fraturas da Coluna Vertebral/etiologia , Inquéritos e Questionários , Saúde da Mulher
17.
Med Clin (Barc) ; 119(19): 721-4, 2002 Nov 30.
Artigo em Espanhol | MEDLINE | ID: mdl-12487966

RESUMO

BACKGROUND AND OBJECTIVE: To know the durability of consecutive regimens of antiretroviral treatment is important to design a long-term therapy, but there is not much information about this subject. PATIENTS AND METHOD: Retrospective epidemiological study of a sample of 401 patients who began antiretroviral treatment between January 1997 and April 2000 at ten Spanish hospitals. The duration of each consecutive antiretroviral regimen was calculated and the reasons for modification and discontinuation were described. RESULTS: In the 3 years and 3 months covered by the study, 48.6% of the patients received more than one regimen of therapy. Seventy five of the initial prescribed combinations included protease inhibitors. Median duration of consecutive lines of therapy was decreasing: 560, 360, 330 and 202 days for the first, second, third and fourth regimens, respectively. The main reason to modification was intolerance or toxicity (46.2, 49.1 and 47.1% for the first, second and third modification). A fifth of changes was originated by difficulties to follow the therapy. Virological failure was the reason for modification in 21.8, 24.5 and 26.5% of first, second and third changes. CONCLUSIONS: Duration of consecutive antiretroviral regimens progressively decreases. Intolerance or drug toxicity were the main reasons conditioning the change of treatment.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Adulto , Feminino , Humanos , Masculino , Estudos Retrospectivos , Espanha , Fatores de Tempo
18.
J Biomed Opt ; 19(12): 127006, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25539187

RESUMO

This study presents a method for measuring scattering in explanted intraocular lenses (IOLs). Currently, determining scattering in IOLs is usually performed by Scheimpflug cameras and the results are expressed in the units used by this apparatus. The method we propose uses a spectrophotometer and this makes it possible to measure the total transmission of the IOL by using an integrating sphere; the direct transmission is determined by the double-beam mode. The difference between these two transmissions gives a value of the scattering in percentage values of light lost. In addition, by obtaining the spectral transmission curve, information about the most scattered wavelengths is also obtained. The IOL power introduces errors when directly measured, particularly with high powers. This problem can be overcome if a tailor-made cuvette is used that shortens the distance between the IOL and the condensing lens of the spectrophotometer when the IOL powers are below 24 diopters. We checked the effectiveness of this method by measuring the scattering of three explanted IOLs from cornea donors. This method, however, does not make it possible to ascertain whether the scattering measured is caused by surface light scattering or internal light scattering.


Assuntos
Lentes Intraoculares , Espalhamento de Radiação , Espectrofotometria/métodos , Luz , Teste de Materiais
19.
Arq. bras. oftalmol ; 82(1): 56-61, Jan.-Feb. 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-973867

RESUMO

ABSTRACT Purpose: The porcine eye is frequently used as a research model. This paper analyzes the effect of different storage methods on the transparency of pig crystalline lens. Methods: A spectral transmission curve (from 220 to 780 nm) for the crystalline lens was determined experimentally after storage in different conditions: saline solution, formalin, castor oil, and freezing at -80°C. The total transmission in the visible spectrum, which was used as an index of transparency, was calculated from these curves. For comparative purposes, fresh lenses were evaluated and used as controls. Results: Storing the porcine crystalline lens in saline solution or castor oil resulted in a transparency loss of approximately 10% after 24 h and storage in formalin resulted in a loss of nearly 30%. Storage by freezing at -80°C for 4 weeks maintained the transparency of the crystalline lens; the spectral transmission measured immediately after defrosting at room temperature coincided exactly with that of the freshly extracted lens. Conclusions: The transparency of porcine crystalline lens is affected by the storage method. The visible spectrum is the most affected, evidenced by the effect on the transparency and consequently the amount of light transmitted. The results show that freezing at -80°C maintains the transpa rency of the crystalline lens for at least 4 weeks.


RESUMO Objetivos: Olho de porco é frequentemente usa do como modelos de pesquisa. Este estudo analisa o efeito de di ferentes métodos de armazenamento na preservação da transparência do cristalino de porco. Métodos: Uma curva de transmissão espectral (de 220 até 780 nm) para o cristalino foi experimentalmente determinada após armazenamento em diferentes condições: solução salina, formol, óleo de mamona e congelamento a -80°C. Transmissão total do espectro visível, que foi usada como um índice de transparência foi calculada a partir dessas curvas. Para fins comparativos, lentes frescas foram avaliadas e usadas como controles. Resultados: O armazenamento do cristalino suíno em solução salina ou óleo de mamona resultou uma perda de transparência de aproximadamente 10% após 24 h e o armazenamento em formol resultou uma perda de quase 30%. O armazenamento por congelamento a -80°C durante 4 semanas manteve a transparência do cristalino; a transmissão espectral medida imediatamente após o descongelamen to à temperatura ambiente coincidiu exatamente com a da lente extraída recentemente. Conclusão: A transparência do cristalino suíno é afetada pelo método de armazenamento. O espectro visível é o mais afetado, evidenciado pelo efeito sobre a transparência e consequentemente a quantidade de luz transmitida. Os resultados mostram que o congelamento a -80°C mantém a transparência do cristalino suíno por pelo menos 4 semanas.


Assuntos
Animais , Preservação de Órgãos/métodos , Cristalino/anatomia & histologia , Valores de Referência , Espectrofotometria/instrumentação , Espectrofotometria/métodos , Suínos , Fatores de Tempo , Raios Ultravioleta , Óleo de Rícino/química , Reprodutibilidade dos Testes , Modelos Animais , Formaldeído/química , Congelamento , Cristalino/fisiologia , Cristalino/diagnóstico por imagem , Luz
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