Histochemical and ultrastructural studies on the islets of langerhans of lean and obese hyperglycaemic mice with age

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The electroretinogram:a useful tool for evaluating age-related macular disease?

With an ageing population, the number of age-related macular disease (ARMD) cases will inevitably rise. This gives greater impetus for the need to identify the disease earlier and assess treatments to slow disease progression. Differing electroretinogram (ERG) modalities have been reviewed in relation to the objective assessment of retinal function in ARMD and for monitoring the effectiveness of clinical interventions. Conflicting results have been found with regard to the efficacy of ERG findings in the investigation of ARMD in previous years. The newer multifocal ERG paradigm provides spatial topographical information about retinal function in ARMD. It has shown promising results in monitoring effectiveness of clinical interventions and studies are continuing in this area. Better knowledge of retinal function in ARMD may lead to enhanced treatments at each phase of the disease.

Economic life in the modern age

Werner Sombart (1863-1941) may well have been the most famous and controversial social scientist in Germany during the early twentieth century. Highly influential, his work and reputation have been indelibly tainted by his embrace of National Socialism in the last decade of his life. Although Sombart left an enormous opus spanning disciplinary boundaries, intellectual reaction to his work inside and outside of Germany is divided and ambivalent. Sombart consistently responded to the social and political developments that have shaped the twentieth century. Economic Life in the Modern Age provides a representative sampling of those portions of Sombart's work that have stood the test of time. The volume opens with a substantial introduction reviewing Sombart's life and career, the evolution of his major intellectual concerns, his relation to Marx and Weber, and his political affiliation with the Nazis. The editors' selection of texts emphasizes areas of Sombart's economic and cultural thought that remain relevant, particularly to those intellectual trends that seek a more broadly based, cross-disciplinary approach to culture and economics. Sombart's writings on capitalism are represented by essays on the nature and origin of the market system and the diversity of motives among the bourgeoisie and the proletariat. Also included is an excerpt from Sombart's controversial The Jews and Modern Capitalism, exploring the widely perceived relation between economic life and Judaism as a religion. In essays on the economics of cultural processes, Sombart's comprehensive and expansive idea of cultural science yields prophetic insights into the nature of urbanism, luxury consumption, fashion, and the cultural secularization of love. The volume's final section consists of Sombart's reflections on the social influences of technology, the economic life of the future, and on socialism, including the influential essay "Why is there no Socialism in the United States." Encapsulating the most valuable aspects of his work, Economic Life in the Modern Age provides clear demonstration of Sombart's sense for fine cultural distinctions and broad cultural developments and the predictive power of his analyses. It will be of interest to sociologists, economists, political scientists, and specialists in cultural studies.

Studies on the growth rates of lichens

Progress in the field of lichen growth rates is briefly reviewed. The application of a new method of measuring growth rate to thalli of different size has led to the conclusion that there are changes in the radial growth rate during the life of a lichen thallus. For most of the life of a lichen thallus the radial growth rate is constant and the thallus radius increases linearly. Preceeding the linear phase the radial growth rate increases with time and the thallus radius increases logarithmically. There is no evidence for a postlinear phase in the radial growth of a lichen thallus. Studies on the growth rate of lichens are applied both to the problems of determining the age of a lichen thallus on an undated substratum and to an ecological investigation in the field.

Studies on the growth rates of lichens

Progress in the field of lichen growth rate studies is briefly reviewed. The application of a new method of measuring growth rate to thalli of different size has led to the conclusion that there are changes in the radial growth rate during the life of a lichen thallus. For most of the life of a lichen thallus the radial growth rate is constant and the thallus radius increases linearly. Preceding the linear phase the radial growth rate increases with time and the thallus radius increases logarithmically. There is no evidence for a postlinear phase in the radial growth of a lichen thallus. Studies on the growth rate of lichens are applied both to the problems of determining the age of a lichen thallus on an undated susbtratum and to an ecological investigation in the field.

A comparison of the vocational training system of Britain and West Germany as experienced by minimum-age school leavers.

The sectoral and occupational structure of Britain and West Germany has increasingly changed over the last fifty years from a manual manufacturing based to a non-manual service sector based one. There has been a trend towards more managerial and less menial type occupations. Britain employs a higher proportion of its population in the service sector than in manufacturing compared to West Germany, except in retailing, where West Germany employs twice as many people as Britain. This is a stable sector of the economy in terms of employment, but the requirements of the workforce have changed in line with changes in the industry in both countries. School leavers in the two countries, faced with the same options (FE, training schemes or employment) have opted for the various options in different proportions: young Germans are staying longer in education before embarking on training and young Britons are now less likely to go straight into employment than ten years ago. Training is becoming more accepted as the normal route into employment with government policy leading the way, but public opinion still slow to respond. This study investigates how vocational training has adapted to the changing requirements of industry, often determined by technological advancements. In some areas e.g. manufacturing industry the changes have been radical, in others such as retailing they have not, but skill requirements, not necessarily influenced by technology have changed. Social-communicative skills, frequently not even considered skills and therefore not included in training are coming to the forefront. Vocational training has adapted differently in the two countries: in West Germany on the basis of an established over-defined system and in Britain on the basis of an out-dated ill-defined and almost non-existent system. In retailing German school leavers opt for two or three year apprenticeships whereas British school leavers are offered employment with or without formalised training. The publicly held view of the occupation of sales assistant is one of low-level skill, low intellectual demands and a job anyone can do. The traditional skills - product knowledge, selling and social-communicative skills have steadily been eroded. In the last five years retailers have recognised that a return to customer service, utilising the traditional skills was going to be needed of their staff to remain competitive. This requires training. The German retail training system responded by adapting its training regulations in a long consultative process, whereas the British experimented with YTS, a formalised training scheme nationwide being a new departure. The thesis evaluates the changes in these regulations. The case studies in four retail outlets demonstrate that it is indeed product knowledge and selling and social-communicative skills which are fundamental to being a successful and content sales assistant in either country. When the skills are recognised and taught well and systematically the foundations for career development in retailing are laid in a labour market which is continually looking for better qualified workers. Training, when planned and conducted professionally is appreciated by staff and customers and of benefit to the company. In retailing not enough systematic training, to recognisable standards is carried out in Britain, whereas in West Germany the training system is nevertheless better prepared to show innovative potential as a structure and is in place on which to build. In Britain the reputation of the individual company has a greater role to play, not ensuring a national provision of good training in retailing.

Genetic studies of Cu-Pb-Zn mineralisation in Triassic red beds of Western Europe

Continental red bed sequences are host, on a worldwide scale, to a characteristic style of mineralisation which is dominated by copper, lead, zinc, uranium and vanadium. This study examines the features of sediment-hosted ore deposits in the Permo-Triassic basins of Western Europe, with particular reference to the Cu-Pb-Zn-Ba mineralisation in the Cheshire Basin, northwest England, the Pb-Ba-F deposits of the Inner Moray Firth Basin, northeast Scotland, and the Pb-rich deposits of the Eifel and Oberpfalz regions, West Germany. The deposits occur primarily but not exclusively in fluvial and aeolian sandstones on the margins of deep, avolcanic sedimentary basins containing red beds, evaporites and occasionally hydrocarbons. The host sediments range in age from Permian to Rhaetian and often contain (or can be inferred to have originally contained) organic matter. Textural studies have shown that early diagenetic quartz overgrowths precede the main episode of sulphide deposition. Fluid inclusion and sulphur isotope data have significantly constrained the genetic hypotheses for the mineralisation and a model involving the expulsion of diagenetic fluids and basinal brines up the faulted margins of sedimentary basins is favoured. Consideration of the development of these sedimentary basins suggests that ore emplacement occurred during the tectonic stage of basin evolution or during basin inversion in the Tertiary. ð34S values for barite in the Cheshire Basin range from 13.8% to 19.3% and support the theory that the Upper Triassic evaporites were the principal sulphur source for the mineralisation and provided the means by which mineralising fluids became saline. In contrast, δ34S values for barite in the Inner Moray Firth Basin (mean δ34S = + 29%) are not consistent with simple derivation of sulphur from the evaporite horizons in the basin and it is likely that sulphur-rich Jurassic shales supplied the sulphur for the mineralisation at Elgin. Possible sources of sulphur for the mineralisation in West Germany include hydrothermal vein sulphides in the underlying Devonian sediments and evaporites in the overlying Muschelkalk. Textural studies of the deeply buried sandstones in the Cheshire Basin reveal widespread dissolution and replacement of detrital phases and support the theory that red bed diagenetic processes are responsible for the release of metals into pore fluids. The ore solutions are envisaged as being warm (60-150%C), saline (9-22 wt % equiv NaCl) fluids in which metals were transported as chloride complexes. The distribution of δ34S values for sulphides in the Cheshire Basin (-1.8% to + 16%), the Moray Firth Basin (-4.8% to + 27%) and the German Permo-Triassic Basins (-22.2% to -12.2%) preclude a magmatic source for the sulphides and support the contention that sulphide precipitation is thought to result principally from sulphate reduction processes, although a decrease in temperature of the ore fluid or reaction with carbonates may also be important. Methane is invoked as the principal reducing agent in the Cheshire Basin, whilst terrestrial organic debris and bacterial reduction processes are thought to have played a major part in the genesis of the German ore deposits.

Effects of several coloured interventions on reading performance in age-related macular degeneration (ARMD)

A literature review revealed that very little work has been conducted to investigate the possible benefits of coloured interventions on reading performance in low vision due to ARMD, under conditions that are similar to the real world reading environment. Further studies on the use of colour, as a rehabilitative intervention in low vision would therefore be useful. A series of objective, subject based, age-similar controlled experiments were used to address the primary aims. Trends in some of the ARMD data suggested better reading performance with blue or green illuminance but there were also some individuals who performed better with yellow, or with illuminance of reduced intensity. Statistically, better reading in general occurred with a specialised yellow photochromic lens and also a clear lens than with a fixed lens or a neutral density filter. No reading advantage was gained from using the coloured screen facility of a video-magnifier. Some subjects with low vision were found to have co-existent binocular vision anomalies, which may have caused reading difficulties similar to those produced by ARMD. Some individuals with ARMD benefited from the use of increased local illuminance produced by either a standard tungsten or compact fluorescent lamp. No reading improvement occurred with a daylight simulation tungsten lamp. The Intuitive Colorimeter® can be used to detect and map out colour vision discrimination deficiency in ARMD and the Humphrey 630 Visual Field Analyser can be used to analyse the biocular visual field in subjects with ARMD. Some experiments highlighted a positive effect of a blue intervention in reading with ARMD.

Clinical studies of spatial and temporal aspects of vision: an investigation using psychophysical and electrophysiological techniques

Separate physiological mechanisms which respond to spatial and temporal stimulation have been identified in the visual system. Some pathological conditions may selectively affect these mechanisms, offering a unique opportunity to investigate how psychophysical and electrophysiological tests reflect these visual processes, and thus enhance the use of the tests in clinical diagnosis. Amblyopia and optical blur were studied, representing spatial visual defects of neural and optical origin, respectively. Selective defects of the visual pathways were also studied - optic neuritis which affects the optic nerve, and dementia of the Alzheimer type in which the higher association areas are believed to be affected, but the primary projections spared. Seventy control subjects from 10 to 79 years of age were investigated. This provided material for an additional study of the effect of age on the psychophysical and electrophysiological responses. Spatial processing was measured by visual acuity, the contrast sensitivity function, or spatial modulation transfer function (MTF), and the pattern reversal and pattern onset-offset visual evoked potential (VEP). Temporal, or luminance, processing was measured by the de Lange curve, or temporal MTF, and the flash VEP. The pattern VEP was shown to reflect the integrity of the optic nerve, geniculo striate pathway and primary projections, and was related to high temporal frequency processing. The individual components of the flash VEP differed in their characteristics. The results suggested that the P2 component reflects the function of the higher association areas and is related to low temporal frequency processing, while the Pl component reflects the primary projection areas. The combination of a delayed flash P2 component and a normal latency pattern VEP appears to be specific to dementia of the Alzheimer type and represents an important diagnostic test for this condition.

Objective and psychophysical studies of infant visual development

Distortion or deprivation of vision during an early `critical' period of visual development can result in permanent visual impairment which indicates the need to identify and treat visually at-risk individuals early. A significant difficulty in this respect is that conventional, subjective methods of visual acuity determination are ineffective before approximately three years of age. In laboratory studies, infant visual function has been quantified precisely, using objective methods based on visual evoked potentials (VEP), preferential looking (PL) and optokinetic nystagmus (OKN) but clinical assessment of infant vision has presented a particular difficulty. An initial aim of this study was to evaluate the relative clinical merits of the three techniques. Clinical derivatives were devised, the OKN method proved unsuitable but the PL and VEP methods were evaluated in a pilot study. Most infants participating in the study had known ocular and/or neurological abnormalities but a few normals were included for comparison. The study suggested that the PL method was more clinically appropriate for the objective assessment of infant acuity. A study of normal visual development from birth to one year was subsequently conducted. Observations included cycloplegic refraction, ophthalmoscopy and preferential looking visual acuity assessment using horizontally and vertically oriented square wave gratings. The aims of the work were to investigate the efficiency and sensitivity of the technique and to study possible correlates of visual development. The success rate of the PL method varied with age; 87% of newborns and 98% of infants attending follow-up successfully completed at least one acuity test. Below two months monocular acuities were difficult to secure; infants were most testable around six months. The results produced were similar to published data using the acuity card procedure and slightly lower than, but comparable with acuity data derived using extended PL methods. Acuity development was not impaired in infants found to have retinal haemorrhages as newborns. A significant relationship was found between newborn binocular acuity and anisometropia but not with other refractive findings. No strong or consistent correlations between grating acuity and refraction were found for three, six or twelve months olds. Improvements in acuity and decreases in levels of hyperopia over the first week of life were suggestive of recovery from minor birth trauma. The refractive data was analysed separately to investigate the natural history of refraction in normal infants. Most newborns (80%) were hyperopic, significant astigmatism was found in 86% and significant anisometropia in 22%. No significant alteration in spherical equivalent refraction was noted between birth and three months, a significant reduction in hyperopia was evident by six months and this trend continued until one year. Observations on the astigmatic component of the refractive error revealed a rather erratic series of changes which would be worthy of further investigation since a repeat refraction study suggested difficulties in obtaining stable measurements in newborns. Astigmatism tended to decrease between birth and three months, increased significantly from three to six months and decreased significantly from six to twelve months. A constant decrease in the degree of anisometropia was evident throughout the first year. These findings have implications for the correction of infantile refractive error.

What do we know about the experience of age related macular degeneration? A systematic review and meta-synthesis of qualitative research

Age Related Macular Degeneration (AMD) is the leading cause of registerable blindness with a high medical and societal cost burden. Much of the research examining experiences of living with AMD has been conducted independently with small sample sizes and has failed to impact on practice. Meta-synthesis of qualitative research can improve the understanding of the experience of living with AMD by drawing together findings of qualitative studies. This article presents a systematic review and meta-synthesis of qualitative studies investigating the experience of AMD (literature searched up to April 2012; published studies identified range from 1996 to 2009). The review highlights themes relating to: functional limitations, adaptation and independence; feelings about the future with vision impairment; interaction with the health service; social engagement; disclosure; and the emotional impacts of living with AMD. Attention to the experience of living with AMD can help us to better understand the needs of patients. This meta-synthesis aimed to bring together the findings of qualitative research studies and highlights important areas for consideration when caring for patients with AMD. Our findings suggest that a holistic approach to service provision and support for AMD is needed which takes into account individuals' needs and experiences when coping with and adjusting to living with AMD. This support should aim to reduce stigma, increase social engagement, and develop the psychological resources of patients with AMD.

Quantification of visual field loss in age-related macular degeneration

Background - An evaluation of standard automated perimetry (SAP) and short wavelength automated perimetry (SWAP) for the central 10–2 visual field test procedure in patients with age-related macular degeneration (AMD) is presented in order to determine methods of quantifying the central sensitivity loss in patients at various stages of AMD. Methods - 10–2 SAP and SWAP Humphrey visual fields and stereoscopic fundus photographs were collected in 27 eyes of 27 patients with AMD and 22 eyes of 22 normal subjects. Results - Mean Deviation and Pattern Standard Deviation (PSD) varied significantly with stage of disease in SAP (both p<0.001) and SWAP (both p<0.001), but post hoc analysis revealed overlap of functional values among stages. In SWAP, indices of focal loss were more sensitive to detecting differences in AMD from normal. SWAP defects were greater in depth and area than those in SAP. Central sensitivity (within 1°) changed by -3.9 and -4.9 dB per stage in SAP and SWAP, respectively. Based on defect maps, an AMD Severity Index was derived. Conclusions - Global indices of focal loss were more sensitive to detecting early stage AMD from normal. The SWAP sensitivity decline with advancing stage of AMD was greater than in SAP. A new AMD Severity Index quantifies visual field defects on a continuous scale. Although not all patients are suitable for SWAP examinations, it is of value as a tool in research studies of visual loss in AMD.

Quantification of visual field loss in age-related macular degeneration

Presentation Purpose:To determine methods of quantifying the sensitivity loss in the central 10o visual field in a cross section of patients at various stages of age-related macular degeneration (AMD). Methods:Standard and short-wavelength automated perimetry (SAP and SWAP) visual fields were collected using program 10-2 of the Humphrey Field Analyzer, in 44 eyes of 27 patients with AMD and 41 eyes of 22 normal subjects. Stereoscopic fundus photographs were graded by two independent observers and the stage of disease determined. Global indices were compared for their ability to delineate the normal visual field from early stages of AMD and to differentiate between stages. Results:Mean Deviation (MD) and Pattern Standard Deviation (PSD) varied significantly with stage of disease in SAP (both p<0.001) and SWAP (both p<0.001), but post-hoc analysis revealed overlap of functional values between stages. Global indices of focal loss, PSD and local spatial variability (LSV) were the most sensitive to detecting differences between normal subjects and early stage AMD patients, in SAP and SWAP, respectively. Overall, defects were confined to the central 5°. SWAP defects were consistently greater in depth and area than those in SAP. The most vulnerable region of the 10° field to sensitivity loss with increasing stage of AMD was the central 1°, in which the sensitivity decline was -4.8dB per stage in SAP and -4.9dB per stage in SWAP. Based on the pattern deviation defect maps, a severity index of AMD visual field loss was derived. Threshold variability was considerably increased in late stage AMD eyes. Conclusions:Global indices of focal loss were more sensitive to the detection of early stage AMD from normal. The sensitivity decline with advancing stage of AMD was greater in SWAP compared to SAP, however the trend was not strong across all stages of disease. The less commonly used index LSV represents relatively statistically unmanipulated summary measure of focal loss. A new severity index is described which is sensitive to visual field change in AMD, measures visual field defects on a continuous scale and may serve as a useful measure of functional change in AMD in longitudinal studies. Keywords: visual fields • age-related macular degeneration • perimetry

Understanding the IT-related attitudes and needs of persons with age-related macular degeneration : a case study

In the UK, 20 per cent of people aged 75 years and over are living with sight loss; this percentage is expected to increase as the population ages (RNIB, 2011). Age-Related Macular Degeneration (AMD) is the UK’s leading cause of severe visual impairment amongst the elderly. It accounts for 16,000 blind/partial sight registrations per year and is the leading cause of blindness among people aged 55 years and older in western countries (Bressler, 2004). Our ultimate goal is to develop an assistive mobile application to support accurate and convenient diet data collection on which basis to then provide customised dietary advice and recommendations in order to help support individuals with AMD to mitigate their ongoing risk and retard the progression of the disease. In this paper, we focus on our knowledge elicitation activities conducted to help us achieve a deep and relevant understanding of our target user group. We report on qualitative findings from focus groups and observational studies with persons with AMD and interviews with domain experts which enable us to fully appreciate the impact that technology may have on our intended users as well as to inform the design and structure of our proposed mobile assistive application.

The SECURE study:long-term safety of Ranibizumab 0.5 mg in neovascular age-related macular degeneration

Objective - To evaluate long-term safety of intravitreal ranibizumab 0.5-mg injections in neovascular age-related macular degeneration (nAMD). Design - Twenty-four–month, open-label, multicenter, phase IV extension study. Participants - Two hundred thirty-four patients previously treated with ranibizumab for 12 months in the EXCITE/SUSTAIN study. Methods - Ranibizumab 0.5 mg administered at the investigator's discretion as per the European summary of product characteristics 2007 (SmPC, i.e., ranibizumab was administered if a patient experienced a best-corrected visual acuity [BCVA] loss of >5 Early Treatment Diabetic Retinopathy Study letters measured against the highest visual acuity [VA] value obtained in SECURE or previous studies [EXCITE and SUSTAIN], attributable to the presence or progression of active nAMD in the investigator's opinion). Main Outcome Measures - Incidence of ocular or nonocular adverse events (AEs) and serious AEs, mean change in BCVA from baseline over time, and the number of injections. Results - Of 234 enrolled patients, 210 (89.7%) completed the study. Patients received 6.1 (mean) ranibizumab injections over 24 months. Approximately 42% of patients had 7 or more visits at which ranibizumab was not administered, although they had experienced a VA loss of more than 5 letters, indicating either an undertreatment or that factors other than VA loss were considered for retreatment decision by the investigator. The most frequent ocular AEs (study eye) were retinal hemorrhage (12.8%; 1 event related to study drug), cataract (11.5%; 1 event related to treatment procedure), and increased intraocular pressure (6.4%; 1 event related to study drug). Cataract reported as serious due to hospitalization for cataract surgery occurred in 2.6% of patients; none was suspected to be related to study drug or procedure. Main nonocular AEs were hypertension and nasopharyngitis (9.0% each). Arterial thromboembolic events were reported in 5.6% of the patients. Five (2.1%) deaths occurred during the study, none related to the study drug or procedure. At month 24, mean BCVA declined by 4.3 letters from the SECURE baseline. Conclusions - The SECURE study showed that ranibizumab administered as per a VA-guided flexible dosing regimen recommended in the European ranibizumab SmPC at the investigator's discretion was well tolerated over 2 years. No new safety signals were identified in patients who received ranibizumab for a total of 3 years. On average, patients lost BCVA from the SECURE study baseline, which may be the result of disease progression or possible undertreatment.