Patient‐specific determination of change in ocular spherical aberration to improve near and intermediate visual acuity of presbyopic eyes

The purpose was to determine the optimum negative spherical aberration induction required to improve near and intermediate visual acuity (VA) of presbyopic eyes. A total of 174 normal and diabetic (no retinopathy) presbyopic eyes (age ≥ 40 years) were measured with visual adaptive optics simulator (Voptica, Spain). First, baseline uncorrected VA and aberrations were measured. VA at 40 cm (near), 80 cm (intermediate) and distance was measured. Then, a negative spherical aberration (SA) was added to baseline ocular SA, and VA at all targets was reassessed after correction of distance refractive error. Clinically, baseline SA and root mean square of higher order aberrations were similar between the normal and diabetic presbyopic eyes. Baseline VA of the diabetic eyes at near and intermediate was better than the same of normal eyes (P = 0.001). After SA change, VA at near and intermediate of both normal and diabetic presbyopic eyes improved. However, fewer diabetic eyes needed higher SA change than normal eyes (P = 0.03). The corresponding trends with change in VA at near and intermediate were also similar between the normal and diabetic eyes. Patient‐specific modulation of ocular SA to improve near and intermediate VA in a large cohort of eyes was successful in improving VA, sometimes even distance VA.      

A computational modeling for the detection of diabetic retinopathy severity

Prolonged diabetes ultimately leads to Diabetic Retinopathy (DR) which is one of the leading causes of preventable blindness in theworld. Through advanced image analysis techniques are used for abnormalities detection in retina that define and correlate theseverity of DR. A thorough study is done in this area in recent past years and on the basis of these studies we have developed acomputer based prediction model that is used to determine the severity of DR. To identify severity DR, we have analyzed thehuman eye image. We have extracted some important features from human eye image i.e. Blood Artery, Optical disc, Exudates.Based on these image and data we have designed an automated system for the determination of DR severity. This automated DRseverity assessment methods can be used to predict the clinical case and conditions when young clinicians would agree or disagreewith their more experienced fellow members. The algorithms described in this study may be used in clinical practice to validate orinvalidate the diagnoses. Algorithms or method developed here may also be used for pooling diagnostic knowledge for servingmankind. Here we have described a computational based low cost retinal diagnostic approach which can aid an ophthalmologist toquickly diagnose the various stages of DR. This system can accept retinal images and can successfully detect any pathologicalcondition associated with DR.     

Studies on process optimization methods for rapamycin production using Streptomyces hygroscopicus ATCC 29253

Rapamycin is a high-value product finding immense use as a drug, in organ transplantation, and as a potential immunosuppressant. Optimization of fermentation parameters of rapamycin production by Streptomyces hygroscopicus NRRL 5491 has been carried out. The low titer value of rapamycin in the original producer strain limits its applicability at industrial level. This study aims at improving the production of rapamycin by optimizing the nutrient requirements. Addition of l-lysine increased the production of rapamycin up to a significant level which supports the fact that it acts as precursor for rapamycin production, as found in previous studies. Effect of optimized medium on the Streptomyces growth rate as well as rapamycin production has been studied. The optimization study incorporates one at a time parameter optimization studies followed by tool-based hybrid methodology. This methodology includes the Plackett–Burman design (PBD) method, artificial neural networks (ANN), and genetic algorithms (GA). PBD screened mannose, soyabean meal, and l-lysine concentrations as significant factors for rapamycin production. ANN was used to construct rapamycin production model. This strategy has led to a significant increase of rapamycin production up to 320.89 mg/L at GA optimized concentrations of 25.47, 15.39, and 17.48 g/L for mannose, soyabean meal, and l-lysine, respectively. The present study must find its application in scale-up study for industrial level production of rapamycin.     

Autoacetylation of the MYST Lysine Acetyltransferase MOF Protein

The MYST family of histone acetyltransferases (HATs) plays critical roles in diverse cellular processes, such as the epigenetic regulation of gene expression. Lysine autoacetylation of the MYST HATs has recently received considerable attention. Nonetheless, the mechanism and function of the autoacetylation process are not well defined. To better understand the biochemical mechanism of MYST autoacetylation and the impact of autoacetylation on the cognate histone acetylation, we carried out detailed analyses of males-absent-on-the-first (MOF), a key member of the MYST family. A number of mutant MOF proteins were produced with point mutations at several key residues near the active site of the enzyme. Autoradiography and immunoblotting data showed that mutation of these residues affects the autoacetylation activity and HAT activity of MOF by various degrees demonstrating that MOF activity is highly sensitive to the chemical changes in those residues. We produced MOF protein in the deacetylated form by using a nonspecific lysine deacetylase. Interestingly, both the autoacetylation activity and the histone acetylation activity of the deacetylated MOF were found to be very close to that of wild-type MOF, suggesting that autoacetylation of MOF only marginally modulates the enzymatic activity. Also, we found that the autoacetylation rates of MOF and deacetylated MOF were much slower than the cognate substrate acetylation. Thus, autoacetylation does not seem to contribute to the intrinsic enzymatic activity in a significant manner. These data provide new insights into the mechanism and function of MYST HAT autoacetylation.     

On the age and growth of the freshwater eel (Anguilla anguilla)

The growth of over a 1000 eels from three different watersheds was investigated. Because of the difficulties of sexing eels we were only able to compare the size of females with that of eels with lobulate organs (some of the latter are potential females). Generally female eels grow faster than the others. There was little difference in the growth of eels with lobulate organs even though there was a great difference in the eel population density in the three localities. But, in any one locality there was a large range of growth. It is suggested that the competition for food is most acute amongst the smaller size groups. As they grow, eels tend to become cannibalistic and find small eels and elvers an easy source of food.
The growth of some continental eels has been related to temperature but this is not confirmed by experimental work. Nevertheless eels eat little or nothing at low temperature as is shown by the large percentage of eels with empty stomachs in our samples.     

Arsenic and cadmium resistance in environmental isolates of Yersinia enterocolitica and Yersinia intermedia

Environmental strains of Yersinia enterocolitica representing biotype 1A lack virulence plasmid (pYV) and are regarded as non-pathogenic. Though these occupy a diverse range of environmental niches, nothing is known about their resistance to heavy metals. The minimal inhibitory concentrations (MICs) of various metal ions, namely Ag+, Cu2+, Zn2+, Cd2+, As5+, and As3+, for strains of Yersinia enterocolitica (biotype 1A) and Yersinia intermedia (biotypes 1, 2, and 4), isolated from sewage effluents or pork, were determined. All isolates were resistant (MICs 2.5-5 mM) to Cd2+. The MICs of arsenic varied with bacterial strain and the chemical species of the arsenic used. For the majority of the strains, however, it was between 5-10 mM of Na2HAsO4.7H2O and NaAsO2, and 0.625-2.5 mM of As2O3. Except for one isolate, MICs of Ag+, Cu2+, and Zn2+ for these strains were in the range of 0.3-0.625 mM.