Binocular potential score: a novel concept

OBJECTIVE: To assess the predictive value of an objective system for preoperative binocular potential scoring on the postoperative outcome in horizontal concomitant strabismus. METHODS: A prospective interventional study of 100 patients undergoing surgery for horizontal concomitant strabismus was conducted. The binocular potential score (BPS) was evaluated on the basis of age of onset, duration, intermittency, variability, vision, and responses on synoptophore and Worth four-dot test. Patients were grouped according four grades (I = the best and IV = the weakest). The surgical outcome was evaluated by binocular function and ocular alignment. RESULTS: All patients with a BPS of grade I maintained good binocular function postoperatively. Within-grade analysis revealed a statistically significant improvement in postoperative binocular function in patients with a BPS of grade II (P = .0047), grade III (P = .0030), and grade IV (P = .0143). Grade comparisons showed significant differences between grades II and IV (P = .00) and grades III and IV (P = .0005), but not between grades II and III. CONCLUSIONS: The BPS is a useful tool for predicting surgical outcome and it may be valuable to conduct multicentric trials using this objective measurement.     

Electroconvulsive therapy and venous angiomas: two case reports and review of the literature

According to the American Psychiatric Association, the risk for complications related to the electroconvulsive therapy (ECT) treatment of patients with cerebrovascular malformations is small. The literature contains a number of case studies presenting the uneventful treatment of patients with cerebral aneurysms with ECT. However, there is a paucity of cases presenting ECT in the context of a cerebral venous angioma. In this article, we present 2 cases of patients treated with ECT who were found to have documented venous angiomas. This is followed with a brief review of the literature.     

Purification and characterization of α-amylase in Moroccan locust,Dociostaurus maroccanus Thunberg (Orthoptera: Acrididae) and its inhibition by inhibitors from Phaseolus vulgaris L.

An α-amylase with molecular weight of 73?kDa was purified from midgut of Dociostaurus maroccanus using ammonium sulfate precipitation, gel filtration, and ion exchange chromatography. The optimal pH and temperature were 6 and 45?°C, respectively. As calculated using Lineweaver–Burk plots, the Km was about 0.62?mM and the Vmax was 1.113 (μmol/min/mg protein). Mn²⁺, Hg⁺, Zn²⁺ and ethylene diamine tetraacetic acid (EDTA) decreased α-amylase activity of D. maroccanus, whereas the addition of K⁺, Na⁺, Fe²⁺, Ba⁺, Mg²⁺, Ca²⁺ and Co²⁺ increased enzyme activity. Alpha-amylase inhibitors (AI1, AI2) with molecular weights of 43?kDa and 29?kDa, respectively, were purified from the seeds of Phaseolus vulgaris and its inhibitory effect on purified α-amylase of D. maroccanus was investigated. These inhibitors inhibited the D. maroccanus gut α-amylase activity significantly.     

Effects of the addition of low-dose ketamine to propofol-fentanyl anaesthesia during diagnostic gynaecological laparoscopy

Objectives

Diagnostic gynaecological laparoscopy (DGL) is a brief procedure, generally performed on an outpatient basis. Propofol-fentanyl is often used for anaesthesia in minor outpatient procedures because of its rapid onset, short duration of action and smooth patient awakening. However, propofol has various cardiovascular effects such as reduced arterial pressure, cardiac output and cardiac index. Ketamine is an intravenous anaesthetic and short-acting analgesic that could alleviate the haemodynamic effects of propofol due to its sympathomimetic activity. The aim of this placebo-controlled trial was to evaluate the effects of the addition of low-dose ketamine to propofol-fentanyl anaesthesia in DGL.

Study design

In this double-blind randomized trial, 60 healthy women undergoing gynaecological laparoscopy to investigate infertility were studied. Following injection of midazolam and fentanyl in all patients, the study group (n = 30) received ketamine 0.5 mg/kg and propofol 1–2.5 mg/kg, and the placebo group (n = 30) received saline 0.9% and propofol 1–2.5 mg/kg. Propofol was subsequently infused for the maintenance of anaesthesia.

Results

Patients in the study group had a significantly lower incidence of pain than patients in the placebo group during propofol injection (13% vs 87%, respectively; p < 0.0001). After induction of anaesthesia, 16 (53%) patients in the placebo group and three (10%) patients in the study group had a decreased heart rate (p < 0.001). The decrease in mean arterial pressure was greater in the placebo group compared with the study group (37% vs 7%, respectively; p < 0.001). During the procedure, the total mean ± standard deviation dose of propofol was 420 ± 65 mg in the placebo group and 330 ± 35 mg in the study group (p < 0.001). Pain scores for the first 3 h after the operation were significantly lower in the study group (p < 0.001).

Conclusion

Use of low-dose ketamine with propofol-fentanyl anaesthesia in patients undergoing DGL was associated with less pain during propofol injection, lower incidence of haemodynamic changes, lower total dose of propofol and improved postoperative analgesia.     

Robust-Deep: A Method for Increasing Brain Imaging Datasets to Improve Deep Learning Models’ Performance and Robustness

A small dataset commonly affects generalization, robustness, and overall performance of deep neural networks (DNNs) in medical imaging research. Since gathering large clinical databases is always difficult, we proposed an analytical method for producing a large realistic/diverse dataset. Clinical brain PET/CT/MR images including full-dose (FD), low-dose (LD) corresponding to only 5 % of events acquired in the FD scan, non-attenuated correction (NAC) and CT-based measured attenuation correction (MAC) PET images, CT images and T1 and T2 MR sequences of 35 patients were included. All images were registered to the Montreal Neurological Institute (MNI) template. Laplacian blending was used to make a natural presentation using information in the frequency domain of images from two separate patients, as well as the blending mask. This classical technique from the computer vision and image processing communities is still widely used and unlike modern DNNs, does not require the availability of training data. A modified ResNet DNN was implemented to evaluate four image-to-image translation tasks, including LD to FD, LD+MR to FD, NAC to MAC, and MRI to CT, with and without using the synthesized images. Quantitative analysis using established metrics, including the peak signal-to-noise ratio (PSNR), structural similarity index metric (SSIM), and joint histogram analysis was performed for quantitative evaluation. The quantitative comparison between the registered small dataset containing 35 patients and the large dataset containing 350 synthesized plus 35 real dataset demonstrated improvement of the RMSE and SSIM by 29% and 8% for LD to FD, 40% and 7% for LD+MRI to FD, 16% and 8% for NAC to MAC, and 24% and 11% for MRI to CT mapping task, respectively. The qualitative/quantitative analysis demonstrated that the proposed model improved the performance of all four DNN models through producing images of higher quality and lower quantitative bias and variance compared to reference images.     

Avoidance and escape conditioning adjust adult neurogenesis to conserve a fit hippocampus in adult male rodents

In this study, the connection between cognitive behaviors and the adult rodent hippocampus was investigated. Recording field potentials at performant pathway (PP)–hippocampal dentate gyrus (DG) synapses in transverse slices from the dorsal (d), intermediate (i), and ventral (v) hippocampus showed differences in paired-pulse responses and long-term potentiation in rats. The Barnes maze (BM) and passive avoidance (PA) tests indicated a decrease in escape latency and step-through latency in both rats and mice over training days. A decrease in the use of random or sequential strategy while an increase in the use of direct strategy to search for an escape box occurred in both groups. Evaluation of the levels of neurogenesis markers (Ki67 and BrdU/NeuN) by immunofluorescence assay in the dDG, iDG, and vDG revealed a long-axis disparity in the hippocampal dentate baseline cell proliferation and exposure to the BM and PA task changed the profile of baseline cell proliferation along the DG in both rats and mice. Also, these learning experiences changed the profile of BrdU⁺/NeuN⁺ cells along the DG of rats. Quantitation of hippocampal BDNF protein levels using ELISA exhibited no changes in BDNF levels due to learning experiences in rats. We demonstrate that PP–DG synaptic efficacy and neurogenesis are organized along a gradient. Avoidance and escape conditioning themselves are sufficient to change and calibrate adult neurogenesis along the hippocampal long axis in rodents. Further research will be required to determine the precise mechanisms underlying the role of experience-derived neuroplasticity in cognitive function and decline.     

Experimental Design and Surgical Approach to Create a Spinal Fusion Model in a New Zealand White Rabbit (Oryctolagus cuniculus)

There are several animal models routinely used for study of the spinal fusion process and animal selection largely depends on the scientific question to be answered. This review outlines the advantages and disadvantages of various animal models used to study spinal fusion and describes the New Zealand White (NSW) rabbit which is the most popular preclinical model to study spinal fusion. We outline critical steps required in planning and performing spinal fusion surgery in this model. This includes determination of the required animal number to obtain statistical significance, an outline of appropriate technique for posterolateral fusion and other components of completing a study. As advances in drug delivery move forward and our understanding of the cascade of gene expression occurring during the fusion process grows, performing and interpreting preclinical animal models will be vital to validating new therapies to enhance spinal fusion.     

Health literacy in Suriname

Background: Low health literacy is an independent predictor of cardiovascular mortality. However, data on health literacy in low- and middle-income countries are scarce. Therefore, we assessed the level of health literacy in Suriname, a middle-income country with a high cardiovascular mortality.

Methods: We estimated health literacy in a convenience sample at an urban outpatient center in the capital and at a semirural health center, using the validated Rapid Estimate of Adult Literacy in Medicine adapted for the Dutch language (REALM-D) instrument. REALM-D scores vary from 0 to 66 (all correct). The primary outcome was the level of health literacy. Furthermore, we assessed the effect of age, sex, ethnicity, disease history, research location, and level of education on health literacy with multivariable linear regression.

Results: We included 99 volunteers (52% men; 51% urban research location) with a mean age of 44.9 years (SD 13.4). The mean REALM-D score was moderate: 48.6 (SD 8.1). Greater health literacy was associated with male sex, an urban research location, and a higher educational level.

Conclusion: Health literacy was moderate in these Surinamese participants. Health care workers should take health literacy into account, and targeted interventions should be developed to improve health literacy in Suriname.