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1.
Tissue Cell ; 90: 102514, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39121582

RESUMEN

The vocal folds vibrate to produce voice, undergoing significant stress due to contact and shearing force. The epithelium operates as the primary protective layer of the tissue against stress and vibratory damage, as well as to provide a barrier against foreign organisms and toxins. Within the vocal fold epithelium, non-epithelial cells were identified that may interrupt the epithelium and compromise the epithelial barrier's protective function. Human vocal fold samples with a variety of pathologies were compared to normal vocal folds. Analysis included the number of cells in the epithelium and epithelial thickness. Vocal fold sections from 10 human tissue samples were assessed via H&E staining and immunofluorescent co-labeling. Three cell populations (vimentin expressing, CD-45 expressing, and cells expressing both) were identified within the epithelium. Statistical analysis revealed that the abnormal samples had a significantly greater number of vimentin-positive cells/area within the epithelium compared to the normal samples. Additionally, normal tissue samples had a significantly greater epithelial depth, suggesting a more robust epithelial barrier compared to tissue with pathology. Knowledge of the function of these cells could lead to a better understanding of how the local immune environment near and within vocal fold epithelium changes in the presence of different pathologies.


Asunto(s)
Pliegues Vocales , Pliegues Vocales/citología , Pliegues Vocales/metabolismo , Humanos , Células Epiteliales/metabolismo , Células Epiteliales/citología , Masculino , Epitelio/metabolismo , Femenino , Vimentina/metabolismo , Persona de Mediana Edad
2.
Thromb Update ; 3: 100048, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-38620639

RESUMEN

Background: Patients with severe SARS-CoV-2 infection have been shown to have abnormal coagulation parameters and are at increased risk of thromboembolism. The optimal thromboprophylaxis regimen that minimizes thrombosis without increased risk of serious bleeding is uncertain. Objectives: To describe the efficacy and safety of increased intensity (enhanced) thromboprophylaxis in patients with COVID-19 admitted to the medical intensive care unit (MICU). Methods: This is a retrospective cohort analysis of patients with a diagnosis of COVID-19 admitted to the MICU of an urban safety net hospital. With the exception of patients being supported with extracorporeal membrane oxygenation or on chronic anticoagulation who received therapeutic dosing of anticoagulation, thromboprophylaxis was given as either enoxaparin or unfractionated heparin in doses higher than those recommended for standard prophylaxis, but lower than those used for therapeutic anticoagulation. Main results: Of the 120 patients managed with an enhanced thromboprophylaxis protocol, 6 (5%) experienced thromboembolism as a result of their COVID-19 disease (1 pulmonary embolus, 4 deep vein thromboses, and 1 arterial embolism). Four patients experienced major bleeding while receiving therapeutic anticoagulation. Conclusions: In critically ill patients with COVID-19, increased intensity (enhanced) thromboprophylaxis appears to be effective at preventing clinically significant thromboembolic events without an increased risk of serious bleeding.

3.
Sci Total Environ ; 735: 139459, 2020 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-32485450

RESUMEN

Manure from livestock production has been associated with the contamination of water resources. To date, research has primarily focused on runoff of these contaminants from animal operations into surface water, and the introduction of poultry-derived pathogenic zoonoses and other contaminants into groundwater is under-investigated. We characterized pathogens and other microbial and chemical contaminants in poultry litter, groundwater, and surface water near confined poultry feeding operations (chicken layer, turkey) at 9 locations in Iowa and one in Wisconsin from May and June 2016. Results indicate that poultry litter from large-scale poultry confined feeding operations is a likely source of environmental contamination and that groundwater is also susceptible to such poultry-derived contamination. Poultry litter, groundwater, and surface water samples had detections of viable bacteria growth (Salmonella spp., enterococci, staphylococci, lactobacilli), multi-drug resistant Salmonella DT104 flost and int genes, F+ RNA coliphage (group I and IV), antibiotic resistance genes (ARGs; blaDHA, blaOXA-48, blaTEM, blaCMY-2, tetM), phytoestrogens (biochanin A, daidzein, formononetin), and a progestin (progesterone). In addition, mcr-1 (a colistin ARG), was detected in a groundwater sample and in another groundwater sample, antibiotic resistant isolates were positive for Brevibacterium spp., a potential signature of poultry in the environment. Detectable estrogenicity was not measured in poultry litter, but was observed in 67% of the surface water samples and 22% were above the U.S. Environmental Protection Agency trigger level of 1 ng/L. The transport of microbial pathogens to groundwater was significantly greater (p < 0.001) than the transport of trace organic contaminants to groundwater in this study. In addition to viable pathogens, several clinically important ARGs were detected in litter, groundwater, and surface water, highlighting the need for additional research on sources of these contaminants in livestock dominated areas.


Asunto(s)
Agua Subterránea , Aves de Corral , Animales , Iowa , Estiércol , Agua , Wisconsin
4.
Qual Life Res ; 29(7): 1731-1745, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32246433

RESUMEN

PURPOSE: Individuals with epidermolysis bullosa (EB) present with various clinical manifestations of different severities that affect quality of life (QoL). This systematic review synthesizes the current evidence about the QoL of individuals with EB. METHODS: We included observational studies with people of all age groups, both sexes, and any EB type. Studies with qualitative methodology, chapters of books, meeting proceedings, and abstracts were excluded. RESULTS: In this study, 12 articles comprising 745 individuals were included. More than half of the articles observed lower QoL in individuals with recessive dystrophic EB (RDEB) or junctional EB (JEB). Three articles indicated that EB affected QoL more in women than in men, and one article identified that children with EB suffered more than adults with the disease. Pain was frequently reported. Seven articles identified difficulty in sports, two identified a need for bathing assistance, and three identified eating difficulties. Additionally, participants reported that family relationships and friendships were affected, and they experienced feelings of anxiety and depression. Some of the instruments used evaluated QoL in general dermatologic conditions, and one was specific to EB. CONCLUSION: QoL is more affected in people who have RDEB and JEB. Regarding sex and age, women and children need special care in their monitoring. It is necessary that guidelines on pain management be more disseminated and put into practice. Future studies should use standardized specific instruments to assess the QoL in EB individuals, while considering the particularities of the different age groups.


Asunto(s)
Epidermólisis Ampollosa/psicología , Calidad de Vida/psicología , Estudios Transversales , Femenino , Humanos , Masculino
5.
Br J Dermatol ; 182(3): e89-e114, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32107777

RESUMEN

Epidermolysis bullosa (EB) is a complex rare condition that affects the skin and many parts of the body. Those born with EB have skin so fragile they are called 'butterfly children', their skin is quite simply as fragile as the wing of a butterfly. In the UK it is estimated that there are more than 5,000 people living with EB and 500,000 worldwide. Little clinical guidance for care existed until DEBRA International started a programme to develop clinical practice guidelines (CPGs). There were no previous guidelines and few published studies on foot care in EB so treatment decisions were largely based on individual opinion and experience. The panel - made up of clinical experts and people living with EB representing Australia, the UK, and the USA - aimed to describe foot problems in people of all ages with EB, and summarise current evidence and management. The authors used a logical podiatric (foot) care literature review focussed on patients with EB. The authors found that the evidence in this area was limited but several interventions (treatments) currently practised by podiatrists show positive outcomes. The study allowed the group to make recommendations on how to treat foot and nail disorders in patients with EB. Furthermore, the authors concluded that further research is needed. This is a summary of the study: Foot care in epidermolysis bullosa: evidence-based guideline.


Asunto(s)
Epidermólisis Ampollosa , Australia , Niño , Humanos , Piel
6.
Br J Dermatol ; 182(3): 593-604, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31397882

RESUMEN

This guideline was designed to provide service providers and users with an evidence-based set of current best practice guidelines for people and their families and carers, living with epidermolysis bullosa (EB). A systematic literature review relating to the podiatric care of patients with EB was undertaken. Search terms were used, for which the most recent articles relating to podiatric treatment were identified from as early as 1979 to the present day, across seven electronic search engines: MEDLINE, Wiley Online Library, Google Scholar, Athens, ResearchGate, Net and PubFacts.com. The Scottish Intercollegiate Guidelines Network (SIGN) methodology was used. The first guideline draft was analysed and discussed by clinical experts, methodologists and patients and their representatives at four panel meetings. The resulting document went through an external review process by a panel of experts, other healthcare professionals, patient representatives and lay reviewers. The final document will be piloted in three different centres in the U.K. and Australia. Following an EB community international survey the outcomes indicated six main areas that the community indicated as a priority to foot management. These include blistering and wound management, exploring the most suitable footwear and hosiery for EB, management of dystrophic nails, hyperkeratosis (callus), maintaining mobility and fusion of toes (pseudosyndactyly). The evidence here is limited but several interventions currently practised by podiatrists show positive outcomes.


Asunto(s)
Epidermólisis Ampollosa , Australia , Epidermólisis Ampollosa/terapia , Humanos
7.
Sci Total Environ ; 668: 867-880, 2019 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-30870754

RESUMEN

In many aquatic environments, municipal wastewater treatment facility (WWTF) effluent discharges influence local hydrologic and chemical connectivity between the surface-water and adjacent alluvial shallow-groundwater systems. Fourmile Creek located in Polk County, Iowa received effluent from the Ankeny WWTF for nearly forty years before it was shut down in November 2013. The decommissioning of the municipal WWTF provided a unique opportunity to characterize the recovery from impacts of treated wastewater discharge on water quality at the surface-water/groundwater interface in a shallow, unconfined alluvial aquifer. Dissolved major element and trace element concentrations in Fourmile Creek surface water, hyporheic-zone water, and shallow, unconfined groundwater were monitored upstream and downstream from the WWTF discharge before and after the shutdown. Multivariate statistical techniques including principal component analysis (PCA) and agglomerative hierarchical clustering (AHC) were used to differentiate source-water contributions, characterize elemental components, and describe surface-water/groundwater interaction dynamics. During the post-closure assessment, there was subsurface attenuation of wastewater constituents including Al, B, Cu, Gd, K, Mo, Na, P, Pb, Sb, and Zn. During the same time, groundwater concentrations increased for As, Ba, Ca, Fe, Mg, Mn, SiO2, Sr, and U and represented a profile characteristic of the shallow alluvial aquifer. Hydrologic conditions transitioned from predominantly wastewater infiltration and hyporheic exchange before the WWTF shutdown, to predominantly discharge of native groundwater. Precipitation-driven streamflow events created fluctuations in the groundwater water-table elevations, resulting in variable contact between the saturated and unsaturated zones within the unconfined, alluvial aquifer and intermittent exposure to constituents stored in the sediments. The inorganic fingerprint of municipal wastewater was flushed relatively quickly (≤19 weeks) from the hyporheic zone indicating that processes like diffusion or sorption/desorption that might extend recovery may not be important for many trace elements in this system.

8.
Sci Total Environ ; 559: 53-62, 2016 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-27054493

RESUMEN

Precipitation patterns and nutrient inputs affect transport of nitrate (NO3-N) and phosphorus (TP) from Midwest watersheds. Nutrient concentrations and yields from two subsurface-drained watersheds, the Little Cobb River (LCR) in southern Minnesota and the South Fork Iowa River (SFIR) in northern Iowa, were evaluated during 1996-2007 to document relative differences in timings and amounts of nutrients transported. Both watersheds are located in the prairie pothole region, but the SFIR exhibits a longer growing season and more livestock production. The SFIR yielded significantly more NO3-N than the LCR watershed (31.2 versus 21.3kgNO3-Nha(-1)y(-1)). The SFIR watershed also yielded more TP than the LCR watershed (1.13 versus 0.51kgTPha(-1)yr(-1)), despite greater TP concentrations in the LCR. About 65% of NO3-N and 50% of TP loads were transported during April-June, and <20% of the annual loads were transported later in the growing season from July-September. Monthly NO3-N and TP loads peaked in April from the LCR but peaked in June from the SFIR; this difference was attributed to greater snowmelt runoff in the LCR. The annual NO3-N yield increased with increasing annual runoff at a similar rate in both watersheds, but the LCR watershed yielded less annual NO3-N than the SFIR for a similar annual runoff. These two watersheds are within 150 km of one another and have similar dominant agricultural systems, but differences in climate and cropping inputs affected amounts and timing of nutrient transport.

9.
Clin Exp Dermatol ; 36(6): 579-83; quiz 583-4, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21671991

RESUMEN

This is a report of a study day held in London on 3 March 2010 to discuss measures with which to meet the nutritional requirements of patients with epidermolysis bullosa (EB). Members of national and international multidisciplinary teams (MDTs) caring for patients with EB attended this event. The study day focused on four challenging aspects of management intimately associated with nutritional status in EB, necessitating close cooperation between MDT members: iron-deficiency anaemia, gastrostomy placement and feeding, muscle mass and mobility, and dental health. The study day provided a unique forum for dietitians, doctors, nurses, physiotherapists, psychologists, psychotherapists, dentists, dental hygienists and occupational therapists to share knowledge and debate problems common to all who strive to promote best practice in this rare and complex group of conditions.


Asunto(s)
Epidermólisis Ampollosa/dietoterapia , Apoyo Nutricional/métodos , Adolescente , Adulto , Anemia Ferropénica/prevención & control , Niño , Prestación Integrada de Atención de Salud/organización & administración , Servicios de Salud Dental , Epidermólisis Ampollosa/complicaciones , Epidermólisis Ampollosa/fisiopatología , Ejercicio Físico , Femenino , Gastrostomía/métodos , Humanos , Comunicación Interdisciplinaria , Masculino , Necesidades Nutricionales , Estado Nutricional , Adulto Joven
10.
J Environ Qual ; 40(1): 166-75, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21488505

RESUMEN

A combination of above-normal precipitation during the winter and spring of 2007-2008 and extensive rainfall during June 2008 led to severe flooding in many parts of the midwestern United States. This resulted in transport of substantial amounts of nutrients and sediment from Iowa basins into the Mississippi River. Water samples were collected from 31 sites on six large Iowa tributaries to the Mississippi River to characterize water quality and to quantify nutrient and sediment loads during this extreme discharge event. Each sample was analyzed for total nitrogen, dissolved nitrate plus nitrite nitrogen, dissolved ammonia as nitrogen, total phosphorus, orthophosphate, and suspended sediment. Concentrations measured near peak flow in June 2008 were compared with the corresponding mean concentrations from June 1979 to 2007 using a paired t test. While there was no consistent pattern in concentrations between historical samples and those from the 2008 flood, increased flow during the flood resulted in near-peak June 2008 flood daily loads that were statistically greater (p < 0.05) than the median June 1979 to 2007 daily loads for all constituents. Estimates of loads for the 16-d period during the flood were calculated for four major tributaries and totaled 4.95 x 10(7) kg of nitrogen (N) and 2.9 x 10(6) kg of phosphorus (P) leaving Iowa, which accounted for about 22 and 46% of the total average annual nutrient yield, respectively. This study demonstrates the importance of large flood events to the total annual nutrient load in both small streams and large rivers.


Asunto(s)
Desastres/historia , Inundaciones/historia , Sedimentos Geológicos , Ríos/química , Historia del Siglo XXI , Iowa
11.
Health Phys ; 90(5): 446-58, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16607176

RESUMEN

The fallout in Sweden of radiocesium from nuclear weapons tests during the 1960's (137Cs) and from the Chernobyl accident in 1986 (134Cs and 137Cs) has transferred to humans through different ecological pathways. Data from whole-body burden measurements of 134Cs, 137Cs, and 40K in various Swedish populations between 1964 and 2002 have been compiled. This database enables an evaluation of the temporal and geographical dependence of the transfer of radiocesium from ground deposition to humans and the associated absorbed dose. The body burdens of 137Cs gradually decrease after the peak values reached in 1965 from nuclear weapons fallout and in 1987 from the Chernobyl fallout, but at a varying rate depending on the population. Assuming a dual exponential decrease, a short-term component of typically 1-2 y and a long-term component of 5-10 y are found in urban populations in Sweden. Among reindeer herders and hunters the effective ecological half-time is mono-exponential with a half-time of 5-7 y. The estimated time-integrated effective dose to an individual during a period of 50 y from the Chernobyl fallout is, on average, approximately 10 mSv for reindeer herders, which is 10-100 times higher than the estimated dose received by urban populations in the three major Swedish urban areas (Malmö, Göteborg, and Stockholm).


Asunto(s)
Radioisótopos de Cesio/análisis , Accidente Nuclear de Chernóbil , Guerra Nuclear , Exposición Profesional/análisis , Monitoreo de Radiación/métodos , Ceniza Radiactiva/análisis , Medición de Riesgo/métodos , Carga Corporal (Radioterapia) , Semivida , Humanos , Centrales Eléctricas , Dosis de Radiación , Liberación de Radiactividad Peligrosa , Efectividad Biológica Relativa , Factores de Riesgo , Suecia/epidemiología , Ucrania
12.
Sci Total Environ ; 367(1): 324-40, 2006 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-16504249

RESUMEN

Data from measurements on the body burden of (134)Cs, (137)Cs and (40)K in various Swedish populations between 1959 and 2001 has been compiled into a national database. The compilation is a co-operation between the Departments of Radiation Physics in Malmö and Göteborg, the National Radiation Protection Authority (SSI) and the Swedish Defense Research Agency (FOI). In a previous study the effective ecological half time and the associated effective dose to various Swedish populations due to internal contamination of (134)Cs and (137)Cs have been assessed using the database. In this study values of human body burden have been combined with data on the local and regional ground deposition of fallout from nuclear weapons tests (only (137)Cs) and Chernobyl debris (both (134)Cs and (137)Cs), which have enabled estimates of the radioecological transfer in the studied populations. The assessment of the database shows that the transfer of radiocesium from Chernobyl fallout to humans varies considerably between various populations in Sweden. In terms of committed effective dose over a 70 y period from internal contamination per unit activity deposition, the general (predominantly urban) Swedish population obtains 20-30 microSv/kBq m(-2). Four categories of populations exhibit higher radioecological transfer than the general population; i.) reindeer herders ( approximately 700 microSv/kBq m(-2)), ii.) hunters in the counties dominated by forest vegetation ( approximately 100 microSv/kBq m(-2)), iii.) rural non-farming populations living in sub-arctic areas (40-150 microSv/kBq m(-2)), and iv.) farmers ( approximately 50 microSv/kBq m(-2)). Two important factors determine the aggregate transfer from ground deposition to man; i.) dietary habits (intakes of foodstuff originating from natural and semi-natural ecosystems), and ii.) inclination to follow the recommended food restriction by the authorities. The transfer to the general population is considerably lower ( approximately a factor of 3) for the Chernobyl fallout than during the 1960s and 70s, which is partly explained by a higher awareness of the pathways of radiocaesium to man both by the public and by the regulating authorities, and by the time-pattern of the nuclear weapons fallout during the growth season in Sweden.


Asunto(s)
Radioisótopos de Cesio/análisis , Accidente Nuclear de Chernóbil , Guerra Nuclear , Monitoreo de Radiación , Ceniza Radiactiva , Contaminantes del Suelo/análisis , Carga Corporal (Radioterapia) , Radioisótopos de Cesio/farmacocinética , Encuestas Epidemiológicas , Humanos , Radioisótopos de Potasio/análisis , Radioisótopos de Potasio/farmacocinética , Contaminantes del Suelo/farmacocinética , Suecia
13.
Br J Ophthalmol ; 88(1): 57-61, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-14693774

RESUMEN

BACKGROUND/AIMS: To assess the variability in retinal vessel measurements at different points in the pulse cycle. METHODS: A healthy white male aged 19 years had 30 digitised images taken at three distinct points in the pulse cycle over a one hour period. A pulse synchronised ear clip trigger device was used to capture images at the desired point in the pulse cycle. Two trained graders measured the retinal vessel diameter of one large arteriole, one large venule, one small arteriole, and one small venule 10 times in each of these 30 images. RESULTS: Within an image, variability was similar between graders, pulse point, and vessel type. Across images taken at the same point in the pulse period, the change from the minimum to maximum measurement was between 6% and 17% for arterioles and between 2% and 11% for venules. In addition, measurements of small vessels had greater changes than large vessels and no point in the pulse period was more variable than another. Ignoring pulse cycle increased variability across images in the large venule, but not in the other vessel types. Mixed effect models were fit for each of the vessel types to determine the greatest source of variability. Controlling for pulse point and grader, the largest source of variability for all four vessels measured was across images, accounting for more than 50% of the total variability. CONCLUSION: Measurements of large retinal venules is generally less variable than measurements of other retinal vessels. After controlling for pulse point and grader, the largest source of variation is across images. Understanding the components of variability in measuring retinal vessels is important as these techniques are applied in epidemiological studies.


Asunto(s)
Pulso Arterial , Vasos Retinianos/anatomía & histología , Vasos Retinianos/fisiología , Adulto , Arteriolas/anatomía & histología , Arteriolas/fisiología , Técnicas de Diagnóstico Oftalmológico , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Masculino , Fotograbar , Reproducibilidad de los Resultados , Vénulas/anatomía & histología , Vénulas/fisiología
14.
Neurology ; 61(6): 806-11, 2003 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-14504325

RESUMEN

OBJECTIVE: To examine the relation of retinal microvascular abnormalities and MRI signs of cerebral atrophy in healthy middle-aged people. METHODS: A population-based, cross-sectional study involved 1,684 persons aged 51 to 72 years who had cerebral MRI and retinal photography in 1993 to 1995. Sulcal and ventricular size were quantified from the MRI scans and coded as grades 0 to 9, with sulcal widening (SW) and ventricular enlargement (VE) defined as grades 3 or higher. The presence or absence of retinopathy, microaneurysms, hemorrhages, and other characteristics were defined from retinal photographs using a standardized protocol. Generalized arteriolar narrowing was defined from a computer-assisted measurement of arteriolar diameters from digitized photographs. RESULTS: Persons with retinopathy had higher sulcal (p = 0.001) and ventricular (p = 0.03) grades than persons without retinopathy. After adjusting for age, gender, race, mean arterial blood pressure, diabetes, cigarette smoking, common carotid artery intima-media thickness, and other vascular risk factors, retinopathy was significantly associated with SW (odds ratio [OR], 1.9; 95% CI, 1.2, 3.0) and VE (OR, 1.5; 95% CI, 1.0, 2.3). These associations persisted even in people without diabetes or hypertension (OR 1.9, 95% CI, 0.8, 4.4 for SW; OR 2.7, 95% CI, 1.2, 6.5 for VE). Other retinal arteriolar characteristics (arteriovenous nicking, focal and generalized arteriolar narrowing) were not related to sulcal or ventricular grade. CONCLUSIONS: In healthy, middle-aged people, retinopathy is independently associated with sulcal and ventricular enlargement on MRI. This finding is compatible with the hypothesis that microvascular characteristics may influence the development of cerebral atrophic changes.


Asunto(s)
Encéfalo/patología , Imagen por Resonancia Magnética , Vasos Retinianos/ultraestructura , Envejecimiento/patología , Arteriolas/ultraestructura , Atrofia , Estudios Transversales , Retinopatía Diabética/epidemiología , Femenino , Estudios de Seguimiento , Fondo de Ojo , Humanos , Hipertensión/epidemiología , Incidencia , Masculino , Persona de Mediana Edad , Fotograbar , Reproducibilidad de los Resultados , Hemorragia Retiniana/epidemiología , Factores de Riesgo , Vénulas/ultraestructura
15.
Br J Ophthalmol ; 86(9): 1007-13, 2002 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12185128

RESUMEN

AIM: To examine the relation between blood pressure and retinal microvascular abnormalities in older people. METHODS: The Cardiovascular Health Study is a prospective cohort study conducted in four US communities initiated in 1989 to 1990. Blood pressure was measured according to standardised protocols at each examination. During the 1997-8 examination, retinal photographs were taken of 2405 people aged 69-97 years (2056 without diabetes and 349 with diabetes). Signs of focal microvascular abnormalities (focal arteriolar narrowing, arteriovenous nicking, and retinopathy) were evaluated from photographs according to standardised methods. To quantify generalised arteriolar narrowing, the photographs were digitised and diameters of individual arterioles were measured and summarised. RESULTS: In non-diabetic people, elevated concurrent blood pressure taken at the time of retinal photography was strongly associated with presence of all retinal microvascular lesions. The multivariable adjusted odds ratios, comparing the highest to lowest quintile of concurrent systolic blood pressure, were 4.0 (95% confidence intervals (CI): 2.4 to 6.9, p test of trend<0.001) for focal arteriolar narrowing, 2.9 (95% CI: 1.6 to 5.3, p<0.001) for arteriovenous nicking, 2.8 (95% CI: 1.5 to 5.2, p<0.001) for retinopathy, and 2.1 (95% CI: 1.4 to 3.1, p<0.001) for generalised arteriolar narrowing. Generalised arteriolar narrowing and possibly arteriovenous nicking were also significantly associated with past blood pressure measured up to 8 years before retinal photography, even after adjustment for concurrent blood pressure. These associations were somewhat weaker in people with diabetes. CONCLUSIONS: Retinal microvascular abnormalities are related to elevated concurrent blood pressure in older people. Additionally, generalised retinal arteriolar narrowing and possibly arteriovenous nicking are related to previously elevated blood pressure, independent of concurrent blood pressure. These data suggest that retinal microvascular changes reflect severity and duration of hypertension.


Asunto(s)
Presión Sanguínea/fisiología , Ojo/irrigación sanguínea , Enfermedades de la Retina/fisiopatología , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Retinopatía Diabética/fisiopatología , Femenino , Humanos , Masculino , Microcirculación , Estudios Prospectivos , Retina/fisiopatología
16.
Lancet ; 358(9288): 1134-40, 2001 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-11597667

RESUMEN

BACKGROUND: Retinal microvascular abnormalities reflect damage from hypertension and other vascular processes. We examined the relation of such abnormalities to incident stroke. METHODS: A cohort of 10358 men and women (aged 51 to 72 years) living in four US communities underwent retinal photography and standard grading for retinal microvascular abnormalities. The calibres of all retinal arterioles and venules were measured after digital conversion of the photographs, and a summary arteriole-to-venule ratio (AVR) was calculated as an index of arteriolar narrowing (smaller AVR indicates greater narrowing). Cases of incident stroke admitted to hospital were identified and validated by case record reviews. FINDINGS: Over an average of 3.5 years, 110 participants had incident strokes. After adjustment for age, sex, race, 6-year mean arterial blood pressure, diabetes, and other stroke risk factors, most retinal microvascular characteristics were predictive of incident stroke, with adjusted relative risks of 2.58 (1.59-4.20) for any retinopathy, 3.11 (1.71-5.65) for microaneurysms, 3.08 (1.42-6.68) for soft exudates, 2.55 (1.27-5.14) for blot haemorrhages, 2.26 (1.00-5.12) for flame-shaped haemorrhages, and 1.60 (1.03-2.47) for arteriovenous nicking. The relative risk of stroke increased with decreasing AVR (p=0.03). The associations were similar for ischaemic strokes specifically, and for strokes in individuals with hypertension, either with or without diabetes. INTERPRETATION: Retinal microvascular abnormalities are related to incident stroke. The findings support a microvascular role in the pathogenesis of stroke. They suggest that retinal photography may be useful for cerebrovascular-risk stratification in appropriate populations.


Asunto(s)
Arteriosclerosis , Enfermedades de la Retina/complicaciones , Vasos Retinianos/anomalías , Accidente Cerebrovascular/etiología , Diabetes Mellitus Tipo 2/complicaciones , Femenino , Hemodinámica , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Factores de Riesgo , Fumar/efectos adversos , Accidente Cerebrovascular/epidemiología , Encuestas y Cuestionarios , Estados Unidos/epidemiología
17.
Surv Ophthalmol ; 46(1): 59-80, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11525792

RESUMEN

Retinal microvascular abnormalities, such as generalized and focal arteriolar narrowing, arteriovenous nicking and retinopathy, reflect cumulative vascular damage from hypertension, aging, and other processes. Epidemiological studies indicate that these abnormalities can be observed in 2-15% of the nondiabetic general population and are strongly and consistently associated with elevated blood pressure. Generalized arteriolar narrowing and arteriovenous nicking also appear to be irreversible long-term markers of hypertension, related not only to current but past blood pressure levels as well. There are data supporting an association between retinal microvascular abnormalities and stroke, but there is no convincing evidence of an independent or direct association with atherosclerosis, ischemic heart disease, or cardiovascular mortality. New computer-related imaging methods are currently being developed to detect the presence and severity of retinal arteriolar narrowing and other microvascular characteristics. When reliably quantified, retinal microvascular abnormalities may be useful as risk indicators for cerebrovascular diseases.


Asunto(s)
Enfermedades Cardiovasculares/mortalidad , Hipertensión/mortalidad , Enfermedades de la Retina/complicaciones , Vasos Retinianos/patología , Enfermedades Cardiovasculares/etiología , Humanos , Hipertensión/etiología
18.
Arch Ophthalmol ; 119(4): 554-63, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11296021

RESUMEN

OBJECTIVE: To evaluate photographic measures of cytomegalovirus (CMV) retinitis as surrogate outcomes for changes in vision in patients with CMV retinitis related to the acquired immunodeficiency syndrome. METHODS: Data from 3 clinical trials of CMV retinitis treatments were analyzed. Two photographic assessments of retinitis in eyes involved at baseline were evaluated: progression (lesion border movement > or = 750 microm or occurrence of a new lesion) and change in area of retina involved with retinitis. Vision measures were decline in best-corrected visual acuity and change in visual field. Photographic measures were evaluated as surrogate outcomes based on 4 criteria: (1) association with vision measure; (2) ability to account for treatment-related differences in vision measure; (3) data completeness; and (4) sample size requirements. RESULTS: Data from 1001 involved eyes (666 patients) were analyzed. Progression and change in area involved were predictive of declines in vision measures, accounted for 50% and 66% of the treatment effect on visual field, and were available from 93% and 64% of involved eyes, respectively. Sample size estimates for a clinical trial were smallest with progression as the design outcome. CONCLUSION: Progression and change in area involved met the first and second criteria for surrogate outcomes for visual field loss; a complete evaluation for visual acuity decline was not possible because treatment-related differences were not observed. Progression met the logistical and sample size criteria better than change in area of retina involved with retinitis.


Asunto(s)
Infecciones Oportunistas Relacionadas con el SIDA/diagnóstico , Antivirales/uso terapéutico , Retinitis por Citomegalovirus/diagnóstico , Fotograbar/métodos , Agudeza Visual , Infecciones Oportunistas Relacionadas con el SIDA/tratamiento farmacológico , Adulto , Ensayos Clínicos como Asunto , Retinitis por Citomegalovirus/tratamiento farmacológico , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Resultado del Tratamiento , Campos Visuales
20.
Arch Ophthalmol ; 118(9): 1196-204, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10980764

RESUMEN

OBJECTIVE: To identify ocular and systemic factors that predict advancement of cytomegalovirus (CMV) retinitis during treatment. METHODS: Patients with acquired immunodeficiency syndrome were enrolled in a multicenter clinical trial designed to evaluate foscarnet sodium and ganciclovir sodium as therapy for newly diagnosed CMV retinitis. Ocular characteristics at baseline and measurements of retinitis were assessed from fundus photographs by graders at a fundus photograph reading center. The following measures of advancement were assessed: (1) lesion border movement of at least 750 microm or development of a new lesion in involved eyes; (2) rate of increase in retinal area with CMV in involved eyes; and (3) development of retinitis in uninvolved eyes of patients with unilateral disease at baseline. RESULTS: In eyes with retinitis, risk factors at baseline for advancement while receiving treatment included smaller area involved, active margins of retinitis, and posterior location. Risk factors for development of retinitis in uninvolved fellow eyes included blood and urine cultures positive for CMV and lower CD8(+) T-lymphocyte count. CONCLUSIONS: Lesion characteristics can be used to predict advancement of preexisting disease, whereas only systemic factors are associated with development of bilateral disease. These analyses describe retinitis activity before the introduction of potent antiretroviral therapies but provide an important reference point for patients in whom CMV retinitis develops after failure or intolerance of antiretroviral agents. Arch Ophthalmol. 2000;118:1196-1204


Asunto(s)
Infecciones Oportunistas Relacionadas con el SIDA/fisiopatología , Retinitis por Citomegalovirus/fisiopatología , Infecciones Oportunistas Relacionadas con el SIDA/tratamiento farmacológico , Infecciones Oportunistas Relacionadas con el SIDA/virología , Antivirales/uso terapéutico , Linfocitos T CD8-positivos/inmunología , Retinitis por Citomegalovirus/tratamiento farmacológico , Retinitis por Citomegalovirus/virología , Progresión de la Enfermedad , Foscarnet/uso terapéutico , Ganciclovir/uso terapéutico , Humanos , Recuento de Linfocitos , Factores de Riesgo , Cultivo de Virus
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