Integrating binocular vision assessment in refractive surgery work-up: Proposition and protocol

Refractive surgeries are one of most commonly performed surgeries for correcting visual impairment due to refractive errors. With the increase in demand for refractive surgeries, there is an enormous strain on the operating surgeon for delivering ideal outcomes i.e 20/20 visual acuity. Regression, under-correction and ectasia are the most dreaded complications post-refractive correction, for the surgeon as well as the patient. They have significant effects on the quantity of the vision and most importantly on the quality of life of the patient. With the advent of digital era and jobs requiring the eyes being glued to the screen for hours there has been a surge in the patients presenting with complaints of asthenopia, glare, halos, and difficulty in focusing; pointing towards diagnosis of non-strabismic binocular vision anomalies (NSBVA). NSBVA in a postrefractive surgery patient may masquerade as regression or under-correction. However, timely diagnosis of NSBVA in such patients would prevent the greater harm caused by wrongful re-correction. Home- and office-based vision therapy results in improvement in visual acuity in a large majority of these patients. This preferred practice pattern intends to guide the refractive surgeons to diagnose and treat the postrefractive surgery NSBVA following a case-based and algorithmic approach. It also emphasizes the inclusion of the binocular vision assessment as a part of the pre-operative workup for patients undergoing refractive procedures.     

Incidence and risk factors for urinary retention following laparoscopic inguinal hernia repair

Background

The incidence of postoperative urinary retention (PUR) has been reported to range from 1% to 22% in patients who have undergone laparoscopic inguinal hernia procedures. The objectives of this study were to determine the incidence of PUR and examine different risk factors that may be associated with the development of PUR in patients who have undergone laparoscopic inguinal hernia procedures.

Methods

A retrospective chart review was performed on 350 patients. Demographics, comorbidities, and operative and postoperative information were collected in patients undergoing laparoscopic inguinal hernia repair by 3 general surgeons from 2007 to 2011. Statistical analysis was done on patient demographics, medical histories, anesthesia notes, and postoperative notes to identify risk factors for the development of urinary retention after laparoscopic inguinal hernia repair.

Results

Three hundred fifty consecutive patients who underwent laparoscopic inguinal hernia repairs were reviewed. Twenty-nine patients developed PUR, an incidence of 8.3%. Age ≥60 years and history of benign prostatic hyperplasia showed significance on multivariate analysis, with odds ratios of 3.0 and 11.0 respectively (P < .05). Anesthesia time ≥2 hours (odds ratio, .75) was a contributing perioperative risk factor but only as an independent risk factor (P < .05).

Conclusions

History of benign prostatic hyperplasia, age ≥60 years, and anesthesia time ≥2 hours were significant independent risk factors for urinary retention after laparoscopic inguinal hernia repair. On multivariate analysis, only history of group and age ≥60 years showed significance. This is 1 of the largest studies to show that the development of PUR in laparoscopic inguinal hernia repair patients is a multifactorial process. Further studies should be conducted to corroborate our findings.     

Hapten Optimization for Cocaine Vaccine with Improved Cocaine Recognition

In the absence of any effective pharmacotherapy for cocaine addiction, immunotherapy is being actively pursued as a therapeutic intervention. While several different cocaine haptens have been explored to develop anticocaine antibodies, none of the hapten was successfully designed, which had a protonated tropane nitrogen as is found in native cocaine under physiological conditions, including the succinyl norcocaine (SNC) hapten that has been tested in phase II clinical trials. Herein, we discuss three different cocaine haptens: hexyl norcocaine (HNC), bromoacetamido butyl norcocaine (BNC), and succinyl butyl norcocaine (SBNC), each with a tertiary nitrogen structure mimicking that of native cocaine which could optimize the specificity of anticocaine antibodies for better cocaine recognition. Mice immunized with these haptens conjugated to immunogenic proteins produced high titre anticocaine antibodies. However, during chemical conjugation of HNC and BNC haptens to carrier proteins, the 2β methyl ester group is hydrolyzed, and immunizing mice with these conjugate vaccines in mice produced antibodies that bound both cocaine and the inactive benzoylecgonine metabolite. While in the case of the SBNC conjugate, vaccine hydrolysis of the methyl ester did not appear to occur, leading to antibodies with high specificity to cocaine over BE. Although we observed similar specificity with a SNC hapten, the striking difference is that SBNC carries a positive charge on the tropane nitrogen atom, and therefore, it is expected to have better binding of cocaine. The 50% cocaine inhibitory concentration (IC₅₀) value for SBNC antibodies (2.8 μm ) was significantly better than the SNC antibodies (9.4 μm ) when respective hapten–BSA was used as a substrate. In addition, antibodies from both sera had no inhibitory effect from BE. In contrast to BNC and HNC, the SBNC conjugate was also found to be highly stable without any noticeable hydrolysis for several months at 4 °C and 2–3 days in pH 10 buffer at 37 °C.     

Decision support system for age-related macular degeneration using discrete wavelet transform

Age-related macular degeneration (AMD) affects the central vision and subsequently may lead to visual loss in people over 60 years of age. There is no permanent cure for AMD, but early detection and successive treatment may improve the visual acuity. AMD is mainly classified into dry and wet type; however, dry AMD is more common in aging population. AMD is characterized by drusen, yellow pigmentation, and neovascularization. These lesions are examined through visual inspection of retinal fundus images by ophthalmologists. It is laborious, time-consuming, and resource-intensive. Hence, in this study, we have proposed an automated AMD detection system using discrete wavelet transform (DWT) and feature ranking strategies. The first four-order statistical moments (mean, variance, skewness, and kurtosis), energy, entropy, and Gini index-based features are extracted from DWT coefficients. We have used five (t test, Kullback–Lieber Divergence (KLD), Chernoff Bound and Bhattacharyya Distance, receiver operating characteristics curve-based, and Wilcoxon) feature ranking strategies to identify optimal feature set. A set of supervised classifiers namely support vector machine (SVM), decision tree, \(k\) -nearest neighbor ( \(k\) -NN), Naive Bayes, and probabilistic neural network were used to evaluate the highest performance measure using minimum number of features in classifying normal and dry AMD classes. The proposed framework obtained an average accuracy of 93.70 %, sensitivity of 91.11 %, and specificity of 96.30 % using KLD ranking and SVM classifier. We have also formulated an AMD Risk Index using selected features to classify the normal and dry AMD classes using one number. The proposed system can be used to assist the clinicians and also for mass AMD screening programs.     

Copper nanoparticles anchored onto boron-doped graphene nanosheets for use as a high performance asymmetric solid-state supercapacitor

There is a high demand for high energy and power density in the field of energy storage devices. To rectify these limitations, a novel asymmetric solid-state supercapacitor (ASSC) was designed and fabricated using a copper anchored boron doped graphene nanosheet (CuBG) as a negative electrode and reduced graphene nanoplatelets as a positive electrode with H₂SO₄/PVA as the quasi-solid electrolyte. The CuBG was prepared using a two step hydrothermal process followed by pyrolysis at different temperatures using chemical vapour deposition (CVD), using copper sulphate (CuSO₄) and boron-trioxide (B₂O₃) as precursors, for doping in graphene oxide. Owing to the remarkable structure and morphology of Cu nanoparticles on nanosheets of boron intercalated with graphene oxide, the nanosheets exhibit a high specific capacitance of 483 Fg⁻¹ at 1 Ag⁻¹ with a capacitance retention of 96% after 5000 cycles, respectively, in a two-electrode system. In addition, the designed and fabricated solid state ASSC device of rGO//CuBG exhibited a high energy and power density of 132.5 W h kg⁻¹ and 1000 W kg⁻¹, respectively, in a wide potential window of 2.0 V, with an excellent stability, retaining 91% of its initial specific capacitance after 5000 cycles. The electrochemical capacitance of CuBG was also evaluated in a three and two electrode system using a KOH and KOH/PVA solid electrolyte respectively. A specific capacitance of 87.5 Fg⁻¹ was achieved at 1 Ag⁻¹ using the fabricated asymmetric device with a 31.1 W h kg⁻¹ energy density at a corresponding power density of 800 W kg⁻¹ and an 85% capacitance was retained after 5000 cycles. The kinetics of the interfacial charge transport phenomena were analysed using a Nyquist plot of the electrochemical impedance analysis.

There is a high demand for high energy and power density in the field of energy storage devices.     

Maduromycosis of the brain. Case report.

A rare case of a gas-containing brain abscess due to verified maduromycosis is described. Blackish material over the abscess cavity revealed the fungal elements. The pus from the abscess contained Streptococcus hemolyticus and Klebsiella organisms.     

Constriction velocities of renal afferent and efferent arterioles of mice are not related to SMB expression

BACKGROUND: Constriction of renal arterioles contributes significantly to the control of perfusion and glomerular filtration. Afferent but not efferent arterioles express smooth muscle myosin heavy chain B (SMB) (with a 5'-insert of seven amino acids). The aim of the present study was to investigate (1) the constriction characteristics of afferent and efferent arterioles under physiologic load and (2) whether expression of SMB may causally contribute to these constriction characteristics. METHODS: We compared constriction parameters [constriction amplitude, maximal rate of constriction velocity ("dc/dt(max)"), and time to half-maximal constriction (t(1/2)) of in vitro perfused renal afferent and efferent arterioles of wild-type (smb(+/+)] and homozygous SMB knockout [smb(-/-)] mice upon stimulation with angiotensin II (Ang II) (10(-8) mol/L) and potassium chloride (KCl) (100 mmol/L). SMB expression was investigated by double-labeling immunofluorescence. RESULTS: Contraction amplitude and dc/dt(max) of mouse afferent arterioles upon Ang II stimulation were significantly greater compared to efferent arterioles. However, constriction amplitudes, dc/dt(max), and t(1/2) of afferent as well as efferent arterioles upon Ang II stimulation were similar in smb(+/+) and smb(-/-) mice. Constriction amplitudes upon KCl stimulation of afferent arterioles were similar in both smb(+/+) and smb(-/-) mice. Furthermore, KCl-induced dc/dt(max) and t(1/2) of afferent arterioles were similar in both smb(+/+) and smb(-/-) mice. SMB expression could be detected in afferent but not efferent arterioles in smb(+/+) mice. No SMB expression in either arteriole could be observed in smb(-/-) mice. CONCLUSION: Our results suggest that the presence of different alternatively 5'-spliced smooth muscle-myosin heavy chain (SM-MHC) isoforms does not dominate the different contractile features of physiologically loaded renal afferent or efferent arterioles.