Bullous X linked retinoschisis: clinical features and prognosis

BACKGROUND/AIMS: A subset of patients with X linked retinoschisis (XLRS) have bullous schisis cavities in the peripheral retina. This study describes the characteristics and prognosis of the bullous form of XLRS. METHODS: A retrospective case series was performed of nine patients with molecularly proven bullous XLRS seen at a single tertiary centre. RESULTS: All cases of bullous peripheral schisis were bilateral, with one unilateral case at presentation which developed into bilateral bullous schisis over time. The mean age of onset was 1.9 years (range: 1 month-7 years, SD: 2.1 years) and at clinical diagnosis was 5.9 years (range: 1 month-27 years, SD: 9.0 years). Mean follow-up was 11 years (range: 6 months-36 years, SD: 10.8 years). Strabismus was the most common presentation (n=7). Other presenting complaints included decreased vision, floaters and an irregularly shaped pupil. The most frequently associated ocular features were strabismus (100%), vitreous haemorrhage (4/18 eyes, 22%), nystagmus (2/9, 22%) and persistent fetal vasculature (1/18, 6%). Localised tractional detachment was seen in 2/18 (11%) eyes, total detachment that underwent surgical repair in 1/18 (6%) and pigmented demarcation lines in a further 22% of the eyes. There was one eye with exudative retinal detachment. CONCLUSION: In XLRS, bullous schisis may be congenital or develop soon after birth and most commonly presents with strabismus. Cases may be complicated by some form of retinal detachment, which may be tractional or a Coats-like exudative detachment

Temperature dependence of J–V and C–V characteristics of n-InAs/p-GaAs heterojunctions prepared by flash evaporation technique and liquid phase epitaxy

In this work, n-type of InAs films have been successfully fabricated on p-GaAs monocrystalline substrates by both flash evaporation technique and liquid phase epitaxy. The elemental composition of the prepared films has been confirmed by energy dispersive X-ray (EDX) spectroscopy. The morphology of the films has been characterized by scanning electron microscopy (SEM). The current transport mechanisms of n-InAs/p-GaAs heterojunctions in the temperature range 300-400 K have been investigated. Temperature-dependent dark current density-voltage (J–V) studies under forward and reverse bias have been carried out for this purpose. In the temperature range studied, the dark current contribution in the low bias range is believed to be due to the generation-recombination of minority carriers in the space-charge region. A change in the preparation technique does not seem to have altered the dark current conduction mechanism. Capacitance-voltage (C–V) at various temperatures has been measured to identify the junction type as well as determination of the important junction parameters

A phylogeny analysis on six mullet species (Teleosti: Mugillidae) using PCR-sequencing method

In this study, genetic differences and phylogenic relationships among six Mugillidae species (Mugil cephalus, M. capito, Liza subviridis, L. saliens, L. aurata, Valamugil buchanani) were determined using PCR-sequencing. M. cephalus, L. subviridis, and V. buchanani from the Persian Gulf and Oman Sea, and L. aurata and L. saliens from the Caspian Sea were collected. Samples of an imported, Egyptian species M. capito were obtained from the Gomishan Research Center in Gorgan. Total DNA from the samples were extracted according to phenol-chloroform procedure. The extracted total DNAs were amplified using polymerase chain reaction (PCR) and then sequenced. The number of bases in the mitochondrial 16s rRNA genome used in this study approximated 600 base pairs. The size of the bands was identical in all the studied species and no heteroplasmia was observed. In addition, the numbers of variable, preserved, and Pi sites were about 114/624, 488/624, and 110/624, respectively. Analysis of the sequences showed great differences between Mugil species and the other studied species. The phylogenetic tree obtained through Neighbor-Joining method revealed that L. saliens and L. aurata were in the same branch while L. subviridis was in a separate branch. In contrast, Maximum Parsimony tree located L. subviridis and L. aurata in a single branch and assigned L. saliens to a distinct branch. This result brings in the question of monophyletic origin of the genus Liza

Evaluation of combined disc method for the detection of metallo-β-lactamase producing Gram negative bacilli

Aims: Infections due to metallo-β-lactamase (MBL) producing Gram negative rods are a cause of high mortality and morbidity. Early detection by an economical and accurate method may improve patient outcome. This study was aimed to evaluate the diagnostic accuracy of combined disc method for MBL detection by comparing it with MBL-Etest.Methodology and Results: This cross-sectional, validation study was carried out in the Department of Microbiology, Army Medical College, National University of Sciences and Technology, Rawalpindi, over a period of six months. A total of 52 non-duplicate Gram-negative rods isolated from the routine clinical specimens and found resistant to meropenem/imipenem on Kirby Bauer Disc Diffusion method were subjected to two tests for metallo-β-lactamase detection. One was combined Disc test using imipenem with Ethylene Diamine Tetraacetic Acid (EDTA), where a strain showing an increase in zone of inhibition of combined disc of ≥ 7 mm as compared to imipenem alone, was considered as MBL producer and the other one was MBL-Etest for which results were interpreted as per manufacturer’s guidelines. Combined disc method for MBL detection was found to have a sensitivity, specificity, positive predictive value, negative predictive value and accuracy of 97.5%, 100%, 100%, 92% and 98%.Conclusion, Significance and Impact of study: Combined disc method is an economical and reliable method for metallo-β-lactamase detection which can be used routinely in any laboratory

Chemical Sympathectomy Restores Baroreceptor-Heart Rate Reflex and Heart Rate Variability in Rats With Chronic Nitric Oxide Deficiency

Summary Nitric oxide (NO) plays a crucial role not only in regulation of blood pressure but also in maintenance of cardiac autonomic tone and its deficiency induced hypertension is accompanied by cardiac autonomic dysfunction. However, underlying mechanisms are not clearly defined. We hypothesized that sympathetic activation mediates hemodynamic and cardiac autonomic changes consequent to deficient NO synthesis. We used chemical sympathectomy by 6-hydroxydopamine to examine the influence of sympathetic innervation on baroreflex sensitivity (BRS) and heart rate variability (HRV) of chronic N G -nitro-L-arginine methyl ester (L-NAME) treated adult Wistar rats. BRS was determined from heart rate responses to changes in systolic arterial pressure achieved by intravenous administration of phenylephrine and sodium nitroprusside. Time and frequency domain measures of HRV were calculated from 5-min electrocardiogram recordings. Chronic L-NAME administration (50 mg/kg per day for 7 days orally through gavage) in control rats produced significant elevation of blood pressure, tachycardia, attenuation of BRS for bradycardia and tachycardia reflex and fall in time as well as frequency domain parameters of HRV. Sympathectomy completely abolished the pressor as well as tachycardic effect of chronic L-NAME. In addition, BRS and HRV improved after removal of sympathetic influence in chronic L-NAME treated rats. These results support the concept that an exaggerated sympathetic activity is the principal mechanism of chronic L-NAME hypertension and associated autonomic dysfunction

Influence of Melissa officinalis essential oil and its formulation on Typhlodromips swirskii and Neoseiulus barkeri (Acari: Phytoseiidae)

The toxicity of Melissa officinalis L. essential oil and its formulation (Melissacide) were evaluated against eggs and females of two predatory phytoseiid mites, Typhlodromips swirskii (Athias Henriot) and Neoseiulus barkeri (Hughes), using direct spray. Results indicate that both tested materials were potent on predatory females than egg stage. Typhlodromips swirskii was proved to be more sensitive to the oil and formulation than N. barkeri. Females mortality were (62-100%) in T. swirskii, and (46-69%) in N. barkeri, when both predatory mites were sprayed with LC50 and LC90 of the oil and Melissacide reported on Tetranychus urticae Koch. Females of both predators were suffered from reduction in food consumption when sprayed with two sublethal concentrations of Melissacide, while insignificant differences reported in daily number of eggs deposited by females of T. swirskii, when sprayed with its LC25 value of Melissacide and control

Phase Transformation in Micro-Alloyed Steels

Phase transformation in crystalline solid is an important factor that designs the microstructure and plays a great role in alloy development. Iron has an allotropic form, and this unique metallurgical property leads to phase transformation. Addition of micro-alloying elements enhances the phase transformation scenarios in steels. Phase transformation due to the addition of micro-alloying elements, together with exceptional precipitation hardening capabilities, substantially improves mechanical properties of steels of different grades. Ferrite transforming to other phases reduces the hardenability of steels. Micro-addition of elements forms precipitation in ferrite and austenite, which controls the microstructure and hence the mechanical properties of steels. Besides, interactions between different deformation sequences used in the production of steel and addition of elements as solute or precipitates regulate the microstructure. Ferrite grain refinement depends on the refinement of austenite grain size in one case, and austenite grain size growth can be varied by addition of various elements. Thus, a variety of elements influences phase transformation that leads to significantly modified properties

Combining Machine Learning Classifiers for Stock Trading with Effective Feature Extraction

The unpredictability and volatility of the stock market render it challenging to make a substantial profit using any generalized scheme. This paper intends to discuss our machine learning model, which can make a significant amount of profit in the US stock market by performing live trading in the Quantopian platform while using resources free of cost. Our top approach was to use ensemble learning with four classifiers: Gaussian Naive Bayes, Decision Tree, Logistic Regression with L1 regularization and Stochastic Gradient Descent, to decide whether to go long or short on a particular stock. Our best model performed daily trade between July 2011 and January 2019, generating 54.35% profit. Finally, our work showcased that mixtures of weighted classifiers perform better than any individual predictor about making trading decisions in the stock market