Alteration of timing of secretion of vascular endothelial growth factors is responsible for progression of diabetic retinopathy.

Diabetic retinopathy is one of the most common complications in diabetes mellitus due to persistent hyperglycaemia. Various biochemical mechanisms have been suggested to cause this complication. The authors' present study which included 100 patients of type-2 diabetes mellitus with different stages of diabetic retinopathy and without retinopathy shows that initiation of diabetic retinopathy is associated with increased anaerobic glycolysis and accelerated oxidative stress. Progression of this complication is guided by increased secretion of vascular endothelial growth factors. It is our assumption that increased secretion of vascular endothelial growth factors in early part of this disease e.g. before occurrence of morphological abnormality may modify this complication.

Relation between increased anaerobic glycolysis and visual acuity in long-standing type 2 diabetes mellitus without retinopathy.

In long-standing diabetes mellitus, blood flow to essential organs including the retina is reduced owing to macrovascular and/or microvascular changes. Poor glycolytic pathway of glucose metabolism owing to tissue hypoxia caused by ischemia at capillary bed of essential organs produces excessive lactic acid and less of adenosine triphosphate, which lead to poor cellular function. The purpose of the study was to evaluate the relationship between increased anaerobic glycolysis and visual acuity in type 2 diabetes mellitus without retinopathy. Fifty patients of type 2 diabetes mellitus of 10-12 years duration, without retinopathy, constituted the study group. The controls were 50 age-matched healthy persons without diabetes mellitus. Blood lactate level and best-corrected visual acuity (BCVA) were measured in both the groups. The mean blood lactate level was 1.05 mM/l in the control group and 2.32 mM/l in the study group. BCVA of 20/20 (log MAR 0) was seen in 48 (96%) patients of the control group and in 27 (54%) patients of the study group. BCVA of 20/30 (log MAR 0.2) was seen in 23 (46%) patients in the study group and 2 (4%) in the control group. Association of higher blood lactate level with decreased BCVA in the study group was statistically significant (P< 0.001).

Eye health and adolescence.

Complete development of eyes occurs between 8 and 11 years, though longitudinal growth of axial length may occur up to 13 years (approximately). Except a few, most of the eye diseases affecting adolescence age group are similar to adult type. Diseases like myopia, keratoconus, vernal keratoconjunctivitis, juvenile diabetic retinopathy and injuries to eye are exclusively diseases of adolescence that are commonly encountered. Psychologically, impact of eye disease on adolescent mind may be profound, thinking they might lose their eyesight. Early detection of diseases, prevention of injuries, health education and frequent eye check-up are essential.

Chromosomal aberrations in arsenic-exposed human populations: a review with special reference to a comprehensive study in West Bengal, India.

For centuries arsenic has played an important role in science, technology, and medicine. Arsenic for its environmental pervasiveness has gained unexpected entrance to the human body through food, water and air, thereby posing a great threat to public health due to its toxic effect and carcinogenicity. Thus, in modern scenario arsenic is synonymous with "toxic" and is documented as a paradoxical human carcinogen, although its mechanism of induction of neoplasia remains elusive. To assess the risk from environmental and occupational exposure of arsenic, in vivo cytogenetic assays have been conducted in arseniasis-endemic areas of the world using chromosomal aberrations (CA) and sister chromatid exchanges (SCE) as biomarkers in peripheral blood lymphocytes. The primary aim of this report is to critically review and update the existing in vivo cytogenetic studies performed on arsenic-exposed populations around the world and compare the results on CA and SCE from our own study, conducted in arsenic-endemic villages of North 24 Parganas (district) of West Bengal, India from 1999 to 2003. Based on a structured questionnaire, 165 symptomatic (having arsenic induced skin lesions) subjects were selected as the exposed cases consuming water having a mean arsenic content of 214.96 microg/l. For comparison 155 age-sex matched control subjects from an unaffected district (Midnapur) of West Bengal were recruited. Similar to other arsenic exposed populations our population also showed a significant difference (P < 0.01) in the frequencies of CA and SCE between the cases and control group. Presence of substantial chromosome damage in lymphocytes in the exposed population predicts an increased future carcinogenic risk by this metalloid.

The efficacy of topical administration of brimonidine to reduce ischaemia in the very early stage of diabetic retinopathy in good controlled type-2 diabetes mellitus.

It is now proved that diabetic micro-angiopathy is caused by ischaemia at the capillary bed of retina due to reduced capillary blood flow in long standing type-2 diabetes mellitus. Deranged metabolic process due to chronic hypoxia at the tissue level produces visual and vascular dysfunction. Brimonidine tartrate, an alpha-2 agonist which is commonly used in glaucoma to protect retinal ganglion cells from pressure related ischaemia induced cell apoptosis, is administered in very early stage of non-proliferative diabetic retinopathy to reduce ischaemia at the capillary bed of retina. Improved visual acuity and decreased micro-aneurysm formation, which indicate elimination of ischaemic stimulus at the tissue level, are seen in long standing type-2 diabetes mellitus.

Advanced textile composite ring for Ilizarov external fixator system.

The use of a radiolucent composite material permits easier and more accurate radiographic evaluation of the bone healing process, and results in a much lighter system. The finite element method (FEM) is employed to determine the worst possible in-service loading condition and the ring dimensions are modified accordingly. Half-ring prototypes are produced using two types of composite materials: knitted aramid fibre fabric reinforced epoxy and random short carbon (RSC) fibre reinforced epoxy. The in-plane compressive strength and axial stiffness of the complete frame are tested according to ASTM specifications. The performance is evaluated, and compared with an existing system in simulated in-service conditions.

Quantitative radiographic analysis of fiber reinforced polymer composites.

X-ray radiographic examination of the bone fracture healing process is a widely used method in the treatment and management of patients. Medical devices made of metallic alloys reportedly produce considerable artifacts that make the interpretation of radiographs difficult. Fiber reinforced polymer composite materials have been proposed to replace metallic alloys in certain medical devices because of their radiolucency, light weight, and tailorable mechanical properties. The primary objective of this paper is to provide a comparable radiographic analysis of different fiber reinforced polymer composites that are considered suitable for biomedical applications. Composite materials investigated consist of glass, aramid (Kevlar-29), and carbon reinforcement fibers, and epoxy and polyether-ether-ketone (PEEK) matrices. The total mass attenuation coefficient of each material was measured using clinical X-rays (50 kev). The carbon fiber reinforced composites were found to be more radiolucent than the glass and kevlar fiber reinforced composites.

The landless poor--India's growing problem.

PIP: The bulk of poverty in India is found among those with no land or insufficient land with which to feed themselves. This predicament is a result of both population growth and the failure of the government to create sufficient employment opportunities in rural areas. India's inheritance custom, which calls for a sharing of property among a deceased's heirs, has fragmented farms into ever smaller holdings. The sharecropping system has created obstacles against participation of the rural masses in the development effort. The failure of agrarian reform efforts in India is attributed to the resistance of the powerful land-owning interests, supported by small landowners. Industrialization has not provided employment for the many rural unemployed who drift to the cities. It is not the lack of agricultural investment per se that is the source of the problem of the landless poor. Rather, social and political issues are involved. Large farms tend to obtain whatever aid is available for rural development. The increased use of electrification and mechanization has reduced the amount of employment available for landless workers. Half of India's arable land remains in the hands of 7% of the big land-holders. Thus, the gap between the haves and the have-nots has actually increased as a result of agricultural development. Food production has increased, but the ability of the poor masses to purchase food has decreased. As long as they are weak economically, the poor are likely to remain weak politically. Thus, there is a need for both economic and political reform. Resources must be massively diverted for the benefit of the rural sector, and power must be developed within democratic organizations at the rural level. The consequences of such change may be unacceptable to the elite classes who control the state apparatus and have the power to eradicate poverty and reduce inequality, however.^ieng