Fuzzy analytic hierarchy process based generation management for interconnected power system

Decision makers consistently face the challenge of simultaneously assessing numerous attributes, determining their respective importance, and selecting an appropriate method for calculating their weights. This article addresses the problem of automatic generation control (AGC) in a two area power system (2-APS) by proposing fuzzy analytic hierarchy process (FAHP), an multi-attribute decision-making (MADM) technique, to determine weights for sub-objective functions. The integral-time-absolute-errors (ITAE) of tie-line power fluctuation, frequency deviations and area control errors, are defined as the sub-objectives. Each of these is given a weight by the FAHP method, which then combines them into an single final objective function. This objective function is then used to design a PID controller. To improve the optimization of the objective function, the Jaya optimization algorithm (JOA) is used in conjunction with other optimization techniques such as sine cosine algorithm (SCA), Luus-Jaakola algorithm (LJA), Nelder-Mead simplex algorithm (NMSA), symbiotic organism search algorithm (SOSA) and elephant herding optimization algorithm (EHOA). Six distinct experimental cases are conducted to evaluate the controller's performance under various load conditions, with data plotted to show responses corresponding to fluctuations in frequency and tie-line exchange. Furthermore, statistical analysis is performed to gain a better understanding of the effectiveness of the JOA-based PID controller. For non-parametric evaluation, Friedman rank test is also used to validate the performance of the proposed JOA-based controller.

Radiologically-guided balloon sialoplasty for benign salivary duct obstruction: a 7-year UK service evaluation

Obstructive sialadenitis is the most common cause of non-malignant salivary gland disorders, with salivary gland strictures being responsible for approximately 23% of all benign obstructive disease. Significant advances in minimally invasive techniques, including radiologically-guided balloon sialoplasty, offer the potential for successful treatment with reduced complications. At present there is a paucity of follow-up data regarding patient outcomes and repeat interventions in those undergoing the procedure. Patients with parotid or submandibular gland sialadenitis secondary to gland stricture were identified and underwent radiologically-guided balloon sialoplasty at Queen Alexandra Hospital, Portsmouth, UK between 2015 and 2022. Patient outcomes, complications and reintervention rates were recorded prospectively over the seven-year period and analysed retrospectively. A total of 44 patients underwent radiologically-guided balloon sialoplasty. Forty (89%) underwent sialoplasty for parotid gland disease, with a minority (n = 5) receiving an intervention for submandibular gland strictures. A total of 37 (84%) had their obstruction successfully treated (82% of parotid gland obstructions and 100% of submandibular gland obstructions). Five patients (11%) required a repeat intervention. Seventeen successfully treated patients (85%) who attended follow-up clinic appointments described complete resolution of their symptoms, with the remaining three (15%) describing a partial response. Radiologically-guided balloon sialoplasty for the treatment of benign obstructive sialadenitis secondary to a gland stricture is a safe and effective method of eliminating the obstruction and relieving patients' symptoms. Most patients were symptom free at short-term follow up, with a minority requiring a second sialoplastic intervention.

Improved indirect instantaneous torque control based torque sharing function approach of SRM drives in EVs using hybrid technique

This manuscript proposes an improved indirect instantaneous torque control (IITC) based torque sharing function (TSF) method of switched reluctance motor (SRM) drives in electric vehicles (EVs) using a hybrid system. The proposed hybrid techniques are joint performance of both Reptile Search Algorithm (RSA) and Honey Badger Algorithm (HBA), hence it is named as Enhanced RSA (ERSA) method. Here, an IITC method of SRMs for EVs is utilized. It achieves the requirements of the vehicle, like minimum torque ripple, improved speed range, high effectiveness, and maximal torque per ampere (MTPA). To precisely specify the switched reluctance motor and its magnetic features are measured by the proposed method. The modified Torque sharing function compensates the torque error along with incoming phase, which contains the minimal rate of change of flux linkage. Finally, the ERSA method is implemented to define the best control parameters. Then, the proposed ERSA system is performed on the MATLAB platform and the performance is compared to different existing systems. The MSE for case 1 and case 2 using proposed system attains 0.01093 and 0.01095. The voltage deviation for case 1 and case 2 using proposed system reaches 5 and 5. The power factor for case 1 and case 2 reaches a value of 50 and 40 using the proposed system.

Primary neurolymphomatosis presenting as foot drop: A rare case report

ABSTRACT

Neurolymphomatosis (NL) is the direct infiltration of the peripheral nervous system (PNS) by lymphoma cells and represents the least common form of PNS involvement by lymphoma. Clinical presentation is varied, and early diagnosis remains challenging. Nerve biopsy remains the diagnostic gold standard, use of magnetic resonance imaging (MRI) and fluorodeoxyglucose-positron emission tomography (FDG-PET) may help in diagnosis and selecting targets for biopsy. We report an account of an older male patient who presented with subacute onset multifocal neuropathy involving bilateral lower limbs and left foot drop. The patient was initially misdiagnosed as chronic inflammatory demyelinating polyneuropathy; however radiological assessment revealed fusiform thickening of the L5 nerve root and biopsy from the site revealed extensive infiltration by diffuse large B cell type non-Hodgkin lymphoma (NHL). High index of suspicion is vital to ensure correct diagnosis, timely treatment, and to improve patient survival.

Mucormycosis infection associated with global COVID-19 pandemic - an institutional histopathological study

BACKGROUND

Coronavirus disease 2019 (COVID-19) in the recent times have instilled signs of immunosuppression globally which has further precipitated increasing range of opportunistic infections. Mucormycosis is a distressing opportunistic fungal infection with a high incidence and is the third commonest acute invasive infection following candidiasis and aspergillosis. The aim of the present observational study is to delineate the enigmatic histopathological profile between mucormycosis cases seen prior to pandemic (PPM) and pandemic associated mucormycosis (PAM).

MATERIAL AND METHODS

Tissue archives of 105 histopathologically diagnosed cases of mucormycosis were included and analysed for demographical details and histopathological parameters like fungal load and localization, granuloma formation, necrosis, inflammatory infiltrate and tissue invasion.

RESULTS

0ut of 105 included cases, 11/105 (10.48%) were reported PPM and 94/105 (89.52%) PAM. Among 94 cases of PAM, 51/94 (54%) cases also showed COVID-19 positivity, while 43/94 (46%) did not. Of all the histological variables, increased fungal load and necrosis were observed in PAM relative to PPM cases.

CONCLUSIONS

The histopathological variables like fungal load, necrosis, granuloma formation and tissue invasion, could help the clinician in assessing the clinical status at the time of tissue diagnosis and improve the treatment accordingly.

Intelligent cloud agent based action recognition detection using machine learning

On the lap of this present-day epoch, Human Activity Recognition (HAR) has been of considerable assistance in case of health monitoring and recovery. The utilization of machine learning approach integration with intelligent agent in the area of health informatics collected via Human Activity Recognition enhances the decision making quality and significance. Its specific homogenization into the Smart Healthcare Monitoring permits gathering, examining and learning from Internet of Things (IoT) wearable devices, undoubtedly achieving knowledge and making analysis on the patient’s state. Despite several research works conducted on Smart Healthcare Monitoring, there remains certain amount of pitfalls, like, time, overhead involved in analysis and also the falsification of analysis. To focus on these issues, a Statistical Partial Regression and Support Vector Intelligent Agent Learning (SPR-SVIAL) for Smart Healthcare Monitoring is proposed. The SPR-SVIAL method is split into two stages. First, data pre-processing along with the dimensionality reduced features are extracted by employing Statistical Partial Regression Feature Extraction model. Here, with the ceaseless thump to-pulsate heart information, triaxial accelerometer information, rest quality, actual work and mental attributes obtained from the input dataset acquired from IoT wearable devices, Partial Least Square is applied to extract the dimensionality reduced features, therefore contributing to Smart Healthcare Monitoring time and accuracy. Next, with these resultant features, Support Vector Intelligent Agent Learning is proposed for Smart Healthcare Monitoring that with the aid of Machine Learning and Intelligent Agent not only reduces the falsification of analysis but also reduces the overhead incurred. The SPR-SVIAL method is tested on simulators and the obtained results indicated better performance upon comparison with the other methods. The results show that we can reduce the time, overhead, false positive rate for healthcare monitoring and achieve a high accuracy rate by performing feature extraction for each of the data recording.

Trust based COVID-19 vaccine distribution using blockchain technology

The COVID-19 outbreak has impacted huge number of individuals all around the world and has caused a great economic loss all over the world. Vaccination is most effective solution to prevent this disease. It helps in protecting the whole community. It improves the human immune system and fights against corona virus reducing the death rate. This paper deals with the different types of COVID-19 vaccine and their related distribution, it includes measures to ensure safe and secured distribution of the vaccine through block chain technology with the help of supply chain. Any malfunction in the chain is identified by the trust value of the function point method and the value of the Markov Chain.

Blockchain security in virtual environment

This paper is to improve the privacy and security in the distributed virtual environment using blockchain technology. One of the feature it provides is greater security in the decentralized virtual environment. A key aspect of this technology is used for various fields like healthcare, finance, business and cloud environment. Key issue of the virtual environment is to protect the data privacy and security which is difficult to handle. To overcome this issue, a new security model to protect the virtual environment is created and will focus on different types of attacks in blockchain technology.

SARS-CoV-2-associated haemorrhagic encephalitis mimicking Herpes encephalitis

Although acute encephalopathy is quite commonly seen in patients of SARS-CoV-2 infection, encephalitis characterised by brain inflammation is relatively rare. Encephalitis caused by Herpes simplex type 1 is the most common cause of identified sporadic encephalitis, and early diagnosis and prompt treatment can prevent the devastating outcome. In this brief communication, we report a case of SARS-CoV-2 associated haemorrhagic encephalitis mimicking herpes encephalitis. In today's pandemic era, it is especially important to distinguish herpes encephalitis from SARS-CoV-2-associated encephalitis as treatment and prognosis of both the conditions differ greatly. This case highlights the importance of suspecting SARS-CoV-2 infection in a patient presenting with clinical symptoms and brain imaging suggestive of Herpes encephalitis.

Clinical usefulness of eosinopenia in differentiating COVID-19 versus other flu-like illness in outpatient set-up

Introduction and Aim:Corona virus disease 2019 (Covid-19) is a highly infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). COVID-19 has affected over 200 countries and territories. The aim of the present study is to evaluate the role of eosinopenia in differentiating COVID-19 suspect from other    flu-like illnesses in an outpatient setting.   Materials and Methods:It was a retrospective case control study in which data of 1252 suspected COVID 19 patients who visited the fever clinic were enrolled. Among this, 701 patients were found to have COVID-19 pneumonia and 551 had other flu-like illnesses. CBC (complete blood count) and CRP(C- reactive protein) were taken in all patients along with chest x-ray as routine protocol.   Results:Among the 701 positive patients, eosinopenia was seen in 527 patients and had a sensitivity of 75.2 % and specificity of 68.6 %. When combined with other lab parameters such as the increased CRP and lymphopenia, the specificity rises up to 78.6 %.   Conclusion:Our study shows that eosinopenia as an independent variable, is a reliable marker to differentiate COVID-19 suspect patients from other flu-like illnesses on outpatient basis, however when combined with other parameters like lymphopenia and CRP the specificity increases further.

Two-year results for ranibizumab for radiation retinopathy (RRR): a randomized, prospective trial

PURPOSE

To assess the efficacy of a treat-and-extend strategy with intravitreal ranibizumab for radiation-related macular edema.

METHODS

Forty eyes with radiation-induced macular edema and decreased visual acuity were enrolled in the phase IIb, prospective clinical trial and randomized into 3 cohorts: (A) monthly ranibizumab, (B) monthly ranibizumab with targeted retinal photocoagulation (TRP), or (C) as-needed ranibizumab and TRP. In year 2, all subjects entered a treat-and-extend protocol for ranibizumab. The primary outcome measure was mean change in early treatment diabetic retinopathy study (ETDRS) best-corrected visual acuity (BCVA) from baseline.

RESULTS

Through year 1, the mean change in ETDRS BCVA was significantly different between the three cohorts (p < 0.001); cohort A saw the largest gain with + 4.0 letters. Significant anatomic improvements were also seen in all cohorts. Comparatively, through year 2, cohorts A, B, and C had a mean change in ETDRS BCVA of - 1.9, - 3.9, and + 1.3 letters, respectively; additionally, no significant differences were found in absolute ETDRS BCVA across time (ANOVA, p = 0.123). Overall, 90% of eyes maintained VA 20/200 or better and 33.3% of subjects gained at least one line of vision. There were no significant differences in mean central macular thickness for any cohort compared to baseline (p = 0.09). The presence of retinal hemorrhage and intraretinal exudates stayed consistent from year 1 to year 2 for all cohorts.

CONCLUSIONS

Among eyes with radiation-related macular edema, a treat-and-extend regimen with ranibizumab may not result in as many visual and anatomic improvements as monthly injections. However, treat-and-extend still may prevent serious visual complications compared to historical controls.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02222610.

Health-related quality of life in patients with chronic obstructive pulmonary disease: A hospital-based study

Background & objectives:

Chronic obstructive pulmonary disease (COPD) adversely affects various functional and structural domains of the lungs, in addition to having an array of extra-pulmonary effects which affect overall well-being of a patient. This study was aimed at measuring the health-related quality of life (HRQOL) in COPD patients and relating the severity of disease and other factors with the degree of impairment of HRQOL.

Methods:

This cross-sectional study was conducted on 100 individuals with established COPD aged 45 yr or above. COPD severity was graded based on the Global Initiative for Obstructive Lung Disease (GOLD) staging system. Pulmonary function test was carried out as per the American Thoracic Society and European Respiratory Society task force standardised lung function testing guidelines. The quality of life was measured using the COPD-specific version of the St. George's Respiratory Questionnaire (SGRQ). The three component scores (activity, impact and symptoms) and the total score were compared across the various categories of age, gender and COPD grades. Using multivariable linear regression analysis, the relationship between COPD grades and various component scores, adjusting for age and gender, was determined.

Results:

The mean total SGRQ Classification score was found to be 48.5±17.1. There was a significant increase in the symptom, activity and impact component scores and the total scores of the participants with worsening of COPD grade. The activity, impact component scores and total score showed an increasing trend with age. However, the values of these three scores were lower in participants in the age group of 56-65 yr in comparison to those in the 45-55 yr age group. There was a significant increase in the symptom component score with increasing age across the study population. The difference in the various scores between males and females was not significant.

Interpretation & conclusions:

HRQOL is impaired in patients with COPD, and it deteriorates with increasing severity of the disease. The onset of COPD at a younger age has a much more significant deterioration of HRQOL, due to the early onset of symptoms and complications. These findings call for better early care and integration of pulmonary rehabilitation programmes into current health policies.

Towards practical implementation of the compressed sensing framework for multi-element synthetic transmit aperture imaging

Compressed sensing (CS) has been adapted to synthetic aperture (SA) ultrasound imaging to improve the frame-rate of the system. Recently, we proposed a novel CS framework using Gaussian under-sampling to reduce the number of receive elements in multi-element synthetic transmit aperture (MSTA) imaging. However, that framework requires different receive elements to be chosen randomly for each transmission, which may add to practical implementation challenges. Modifying the scheme to employ the same set of receive elements for all transmissions of MSTA leads to degradation of the recovered image quality. Therefore, this work proposes a novel sampling scheme based on a genetic algorithm (GA), which optimally chooses the receive element positions once and uses it for all the transmission of MSTA. The CS performance using GA sampling schemes is evaluated against the previously proposed CS framework on in-vitro and in-vivo datasets. The obtained results suggest that not only does the GA-based approach allows the use of the same set of sparse receive elements for each transmit, but also leads to the lowest CS recovery error (NRMSE) and 14% overall improvement in image contrast, in comparison to the previously-proposed Gaussian sampling scheme. Thus, using the CS framework along with GA, can potentially reduce the complexity in implementation of CS-framework to MSTA based systems.

Paraneoplastic cerebellar degeneration as a presenting manifestation of non-Hodgkin's lymphoma

Background

Paraneoplastic Cerebellar degeneration (PCD) is one of the classical paraneoplastic syndromes (PNS) which is characterised by subacute onset, progressive cerebellar ataxia and is usually associated with small cell lung carcinoma, adeno carcinoma of breast and ovary followed by Hodgkin’s lymphoma.

Objective

We herein report a case of subacute onset, progressive cerebellar ataxia in a 37-year-old female, who on evaluation was found to have non-Hodgkin’s lymphoma and experienced good clinical response to treatment.

Discussion

As compared to solid tumours, chances of association of PNS with Lymphomas is quite low and there are only few case reports in the literature showing association of PCD with non-Hodgkin’s lymphoma. As PCD is one of the classical PNS, it is very important to identify subtle cerebellar manifestations in an otherwise apparently normal individual, as early diagnosis and aggressive treatment can immensely improve the mortality and morbidity associated with this syndrome.

Conclusion

This case signifies the importance of suspecting PNS as an important differential diagnosis in a young patient presenting with subacute onset progressive cerebellar ataxia and evaluating her extensively for malignancy in spite of no paraneoplastic antibody been detected as early diagnosis and treatment can lead to gratifying response. We do agree that 2 weeks follow up is a short time interval to determine whether the response was sustained or not, for which a long term follow up is required.

Covid-19 associated Guillain-Barre Syndrome: Contrasting tale of four patients from a tertiary care centre in India

Background

Globally, more than 12 million people have been infected with COVID −19 infection till date with more than 500,000 fatalities. Although, Covid-19 commonly presents with marked respiratory symptoms in the form of cough and dyspnoea, a neurotropic presentation has been described of late as well.

Objective

In this brief communication we report four cases of Covid-19 who presented to our hospital with features suggestive of Guillain-Barre Syndrome (GBS).

Discussion

The mechanisms by which SARS-CoV-2 causes neurologic damage are multifaceted, including direct damage to specific receptors, cytokine-related injury, secondary hypoxia, and retrograde travel along nerve fibres. The pathogenesis of GBS secondary to Covid-19 is not well understood. It is hypothesised that viral illnesses related GBS could be due to autoantibodies or direct neurotoxic effects of viruses.

Conclusion

Nervous system involvement in Covid-19 may have been grossly underestimated. In this era of pandemic, it is very important for the physicians to be aware of association of GBS with Covid-19, as early diagnosis and treatment of this complication could have gratifying results. To the best of our knowledge, this is the first such case series of Guillain-Barre Syndrome associated with Covid-19 to be reported from India.

Randomized Trial of Monthly Versus As-Needed Intravitreal Ranibizumab for Radiation Retinopathy-Related Macular Edema: 1-Year Outcomes

PURPOSE

To assess efficacy of intravitreal ranibizumab injections and targeted panretinal photocoagulation (TRP) for radiation retinopathy-related macular edema.

DESIGN

Phase IIb, prospective, randomized clinical trial.

METHODS

Setting: Multicenter.

SUBJECTS

Forty eyes in 40 treatment-naïve patients with radiation-induced macular edema and a resulting decrease in visual acuity ranging between 20/25 and 20/400 (Snellen equivalent).

INTERVENTION

Patients either received intravitreal 0.5 mg ranibizumab monthly, monthly ranibizumab with TRP, or 3 monthly ranibizumab (loading doses) followed by as-needed (PRN) injections and TRP. After week 52, all subjects entered a treat-and-extend protocol for ranibizumab. MainOutcomeMeasures: Mean Early Treatment Diabetic Maculopathy Study (ETDRS) BCVA change from baseline.

RESULTS

Mean patient age was 57 years (range, 22-80 years), ETDRS BCVA was 56.7 letters (20/74 Snellen equivalent), and central macular thickness (CMT) was 423 μm (range, 183-826 μm). Thirty-seven patients completed the month 12 visit (92.5%), at which time the change in mean BCVA was +4.0 letters, -1.9 letters, and +0.9 letters in the monthly, monthly plus laser, and PRN plus laser cohorts, respectively. There was a significant difference in mean BCVA at 1 year among all 3 cohorts (P < .001), as well as between cohorts in pairwise comparisons, with the most significant gains in the monthly group. A total of 82.5% of the patients retained visual acuity of 20/200 or better, and 20.0% improved 10 or more ETDRS letters.

CONCLUSIONS

Ranibizumab may improve vision and anatomy in patients with radiation retinopathy-related macular edema and prevent vision loss through 48 weeks of therapy. Monthly injections were more effective than as-needed approach, and the addition of TRP yielded no therapeutic benefits.

Cardiorenal Amyloidosis

Amyloidosis is a conglomeration of diseases due to production and deposition of amyloid, a proteinaceous substance, into organs, tissues, nerves and other places in the body affecting their normal function. This case report is of a 65 year old gentleman, resident of Bihar admitted with a short history of two months. He came with chief complaints of swelling in both lower limbs associated with heaviness in legs, shortness of breath, dizziness, fatigue and passage of frothy urine for two months. He was investigated and found to have proteinuria, low voltage ECG, Echocardiography showed left ventricular hypertrophy, diastolic dysfunction, mitral regurgitation. Cardiac MRI showed dilated cardiomyopathy due to amyloidosis.

Detection and identification of COVID -19 based on chest medical image by using convolutional neural networks

Covid-19 pandemic has caused major out-break all around the world. This pandemic out-break requires lot of testing, which is a tedious process. Deep learning is a successful method that has evolved in image category in the past few years. In this work to detects the presence of coronavirus by using deep learning approach. Here, convolutional neural networks with specific focus on to classify Covid-19 chest radiography images. The database comprises Covid-19, normal and viral pneumonia chest X-ray images with 800 different samples under each class. We evaluated the model on 500 images and the networks has achieved a sensitivity rate of 95% and specificity rate of 97%. The DenseNet121 Architecture performed slightly better, compared to other state of art networks. The performance achieved by the method proposed is very encouraging and the accuracy rates can be improved further with larger datasets. Apart from sensitivity and specificity rates, the proposed model is also compared on receiver operating characteristic (ROC), and area under the curve (AUC) of each model. The model is implemented on the TensorFlow framework with the datasets that are publicly available for research community.

Lateral Resolution Improvement in Ultrasound Imaging System using Compressed Sensing: Initial Results

Compressed-Sensing (CS) has been applied to ultrasound imaging to reduce data or to reduce the data acquisition time. There appears to be no report that uses CS framework to reduce the number of active receive elements in Conventional Focused Beamforming (CFB). Thus, in our previous work, a novel undersampling scheme based on Gaussian distribution was investigated and reported for reducing the number of active receive elements and data in CFB. In this paper, we exploit the Gaussian sampling based CS framework to improve the lateral resolution (LR) of the ultrasound system without increasing the system's complexity and cost. A notable difference from our previous work being the use of waveatom as the sparsifying basis, instead of 2D-Fourier basis, and analysis of the proposed framework for different receive aperture sizes. Simulation data for this study were generated using Field II, and experimental data were acquired from an in-vitro cyst phantom using Verasonics V-64 ultrasound scanner. The results indicate that the proposed framework of choosing a limited number of receive elements from a receive aperture length that is three or four times the corresponding active aperture size obtained from the same number of consecutive receive elements yields nearly twice an improvement in LR and about 27% increase in contrast to that of CFB reference image. Thus, the findings suggest a possibility to improve the LR of the current ultrasound system without increasing the system complexity, which will be significant for affordable point-of-care ultrasound systems.

Reinforcing mitochondrial functions in aging brain: An insight into Parkinson's disease therapeutics

Mitochondria, the powerhouse of the neural cells in the brain, are also the seat of certain essential gene signaling pathways that control neuronal functions. Deterioration of mitochondrial functions has been widely reported in normal aging as well as in a spectrum of age-associated neurological diseases, including Parkinson's disease (PD). Evidences accumulated in the recent past provide not only advanced information on the causes of mitochondrial bioenergetics defects and redox imbalance in PD brains, but also much insight into mitochondrial biogenesis, quality control of mitochondrial proteins, and genes, which regulate intra- and extra-mitochondrial signaling that control the general health of neural cells. The mitochondrial quality control machinery is affected in aging and especially in PD, thus affecting intraneuronal protein transport and degradation, which are primarily responsible for accumulation of misfolded proteins and mitochondrial damage in sporadic as well as familial PD. Essentially we considered in the first half of this review, mitochondria-based targets such as mitochondrial oxidative stress and mitochondrial quality control pathways in PD, relevance of mitochondrial DNA mutations, mitophagy, mitochondrial proteases, mitochondrial flux, and finally mitochondria-based therapies possible for PD. Therapeutic aspects are considered in the later half and mitochondria-targeted antioxidant therapy, mitophagy enhancers, mitochondrial biogenesis boasters, mitochondrial dynamics modulators, and gene-based therapeutic approaches are discussed. The present review is a critical assessment of this information to distinguish some exemplary mitochondrial therapeutic targets, and provides a utilitarian perception of some avenues for therapeutic designs on identified mitochondrial targets for PD, a very incapacitating disorder of the geriatric population, world over.

Short-duration podcasts as a supplementary learning tool: perceptions of medical students and impact on assessment performance

BACKGROUND

Use of podcasts has several advantages in medical education. Podcasts can be of different types based on their length: short (1-5 min), moderate (6-15 min) and long (>15 min) duration. Short-duration podcasts are unique since they can deliver high-yield information in a short time. The perceptions of medical students towards short-duration podcasts are not well understood and this study aimed to analyze the same. An exploratory analysis of students' podcast usage and performance in summative assessments was also undertaken.

METHODS

First-year medical students (N = 94) participated in the study. Eight audiovisual podcasts, each ≤3 min duration (3-MinuTe Lessons; 3MTLs) were developed for two topics in biochemistry. The podcasts were made available for students after didactic lectures on the topics. Feedback was collected from students about their perceptions to 3MTLs using a self-reported questionnaire. The scores of students in summative assessments were compared based on their usage of 3MTLs.

RESULTS

Feedback revealed that 3MTLs were well received by students as a useful and convenient supplementary tool. Students used 3MTLs for topic review, to get an overview, as well as for quick revision and felt that 3MTLs were helpful in improving their understanding of the topic, clarify concepts and focus on important points and in turn, in preparation for assessments. A significant proportion (49%) felt that 3-min duration was optimal while, an equal proportion suggested an increase in the duration to 5 min with more information. The overall mean scores in assessments were not different between students based on 3MTLs usage. The pairwise comparisons revealed better scores amongst students who used 3MTLs for both topics.

CONCLUSION

Overall, short-duration podcasts were perceived by students as useful supplementary learning tools that aided them for revision and in preparation for assessments.

Macrophage Activation Syndrome

Macrophage Activation Syndrome (MAS) occurs as a severe life-threatening complication of several chronic rheumatic diseases. It is more frequent with systemic onset juvenile arthritis and adult onset Still's disease.1 It can be primary, infection related, malignancy associated or autoimmune3. We report a case of Macrophage Activation Syndrome presenting as pyrexia of unknown origin (PUO) and pancytopenia in the absence of any known triggering factor.

Sulphated Sugar Alpha-Cyclodextrin Sulphate, a Uniquely Potent Anti-HIV Agent, Also Exhibits Marked Synergism with AZT, and Lymphoproliferative Activity

Sulphated sugars, alpha-cyclodextrin sulphate (A-CDS), sodium pentosan polysulphate (PPS), and beta-cyclodextrin sulphate (B-CDS) were evaluated for their inhibitory effect on the replication of human immunodeficiency virus (HIV-1) in normal human peripheral blood mononuclear cells (PMNCs). All three drugs had potent anti-HIV activity, A-CDS being the most potent. A-CDS, PPS and B-CDS were also tested for their direct inhibitory effect on reverse transcriptase (RT) in vitro. PPS inhibited the RT reaction at 4.0 μg ml−1 and above whereas B-CDS and A-CDS did not. The drugs were not cytotoxic up to 100 μg ml−1 and also showed significant lymphoproliferative activities. PPS and B-CDS exhibited higher lymphoproliferative activity than A-CDS. A-CDS, B-CDS, and PPS showed profound antiviral synergism with AZT. An additive anti-HIV effect, rather than a synergestic effect, was observed between the sulphated sugars. Thus, these sulphated sugars, because of their nontoxic nature, lymphoproliferative activity and anti-HIV activity at low concentrations, may be valuable chemotherapeutic agents in the treatment of AIDS. In particular, A-CDS, because of its marked anti-HIV synergism with AZT (which would lower the required dose of AZT in vivo), could result in an efficacious and essentially nontoxic combination chemotherapy for AIDS.

Inhibition of the Binding of HIV rgp120 to CD4 by Dyes

We have found that several dye compounds have the ability to inhibit the binding of HIV rgpl 20 to the Leu3a epitope of CD4 on PBL. One of these compounds, selected for further testing as the best candidate, can inhibit the growth of HIV In vitro. The tested dyes have varying degrees of specificity and efficacy in inhibiting the binding of rgpl 20. These results may point towards compounds that can be useful therapeutics against HIV.

Alpha-Cyclodextrin Sulphate, an anti-HIV Agent, Retains its Antiviral Effect in the Presence of Hydrocortisol Phosphate

Cyclodextrin sulphates alpha (a) and beta (b) were found to be inhibitors of replication of human immunodeficiency virus (HIV-1) in phytohaemagglutinin (PHA)-stimulated human peripheral blood mononuclear cells (PBMC); the same cells were also stimulated to proliferate (Anand et al., 1990). B-Cyclodextrin sulphate was also found to stimulate another, more complex, cell proliferation-neovascularization process in rabbit cornea (Folkman et al., 1989). Since the process of neovascularization is generally associated with progression of tumour growth and other pathologies, it is obvious that its stimulation by an antiviral compound may be a serious side effect. Nevertheless endotoxin-induced neovascularization can be suppressed by simultaneous treatment with b-cyclodextrin sulphate and glucocorticoids (Folkman et al., 1989). The same co-treatment may possibly be used to improve antiviral action of cyclodextrin sulphates, but such a combination therapy may not be free of complications. Glucocorticoids also affect the stability of various cellular membranes. Treatment of cells in vitro by glucocorticoids is known to stabilize their lysozymes. Glucocorticoids affect both the proliferative capacity of the cells (Cristofalo, 1972) and cytopathic effects of rabies viral infection. Furthermore, it has been reported that the cytopathic effects of rabies and of yellow fever viruses were inhibited while those of the polio virus were only mildly affected (Hannoun et al., 1965). Consequently, in this work we evaluated effects of a glucocorticoid and of glucocorticoid-a-cyclodextrin sulphate combination on HIV-1 replication.

CSF ubiquitin as a specific biomarker in Alzheimer's disease

Alzheimer's disease (AD) is the most common cause of dementia worldwide. Although, many putative biomarkers are reported for AD, only a few have been validated in the clinical setting. Ubiquitin levels increase in cerebrospinal fluid (CSF) of patients with AD, but its diagnostic value is not clear. In this present study we evaluate the performance of ubiquitin as a diagnostic marker and deduce a statistical association with disease pathology in AD. Ubiquitin levels were estimated in subjects with AD, other forms of dementias, neurological disorders and healthy age matched population. The levels of ubiquitin were significantly higher in subjects with AD when compared with other groups (p<0.0001). A significant positive correlation was observed between ubiquitin, tau and apolipoprotein Eε4 genotype; with Aβ42 the correlation was negative. By comparing the effect size of the association between ubiquitin and a diagnosis of AD, we find that high ubiquitin levels are specific for AD. We obtained an odds ratio of 5.6 (95% CI 5.0-7.7) for ubiquitin, towards a diagnosis of AD based on clinical criteria, CSF biomarker signature (Aβ42+tau) and apolipoprotein Eε4 genotype. Hence, all our findings taken together provide a strong statistical association linking ubiquitin to the pathology in AD. We also find that, the performance of ubiquitin as a diagnostic marker is comparable to that of CSF Aβ42 or tau or apolipoprotein Eε4 genotype considered individually.