Dual-Mode Virus Detection: Combining Electrochemical and Fluorescence Modalities for Enhanced Sensitivity and Reliability.

This study introduces a dual-mode biosensor specifically designed for the quantitative detection of viruses in rapid analysis. The biosensor is unique in its use of both optical (fluorescence) and electrochemical (impedance) detection methods using the same nanocomposites, providing a dual confirmation system for virus (norovirus-like particles) quantification. The system is based on using two antibody-conjugated nanocomposites: CdSeS quantum dots and Au-N,S-GQD nanocomposites. For optical detection, the principle relies on the fluorescence quenching of CdSeS by Au-N,S-GQD in a sandwich structure with the target. Conversely, electrochemical detection is based on the change in impedance caused by the formation of the same sandwich structure. The biosensor demonstrated exceptional sensitivity, capable of detecting norovirus at concentrations of as low as femtomolar in the electrochemical method and picomolar in the optical method. In the dual-responsive concentration range from 10-13 to 10-10 M, the sensor is highly sensitive in both methods, creating significant changes in fluorescence intensity and impedance in the presence of virus. Furthermore, the biosensor exhibits a high degree of specificity, with a negligible response to nontarget proteins, even within complex test solutions. This work represents a significant advancement in the field of biosensor technology, offering a fast, accurate, and reliable method for diagnosing viral infections and diseases.

PSS functionalized and stabilized carbon nanodots for specific sensing of iron in biological medium.

Carbon Quantum Dots (CQDs) are already emerged as an excellent sensing element for its exceptional behavior in fluorescence, biocompatibility, and water dispersibility. However, its poor stability, selectivity and reproducibility in complex medium still be a big problem for its practical application. To overcome this, in the work, we have developed a new type of carbon quantum dot-PSS fluorescent nanocomposites which has been used for specific Fe3+ detection. The polystyrene sulfonate (PSS) polymer not only stabilize the QDs but also produces specific sites for Fe3+ to make a co-ordinate complex via Fe3+-SO3. The detection limit is calculated as low as 1 ppm which is adequate for measuring Fe3+ in blood or water samples. The mechanism of the quenching is very specific towards the Fe3+ ion due to the presence of PSS which makes the sensor selective among other metal ions and possible interferences. The rapid process of sensing, simple instrumentation, and excellent performances in presence of 1 % BSA and serum samples indicates the possible application for diagnostic usage in near future.

Diagnostic test accuracy of assessment tools for detecting delirium in patients with acute stroke: commentary of a systematic review.

Delirium is a common presentation after acute stroke. Post-stroke delirium is related to poor recovery, higher rates of mortality, falls, and longer hospital stays. Delirium can lead to challenging behaviour such as anger, aggression, and confusion. As such, it is important to identify delirium promptly for early management and to reduce the negative impact on post-stroke recovery and outcomes. An important aspect of identifying delirium depends on the use of efficient, easy to use and validated assessment tools. A wide range of tools are available, although it is not known how accurately they can identify post-stroke delirium. This article critically appraises a systematic review which identified delirium screening tools for patients with acute stroke, and summarised their accuracy.

Long-term use of doxycycline can improve chronic asthma and possibly remodeling: the result of a pilot observation.

UNLABELLED: Progressive loss of lung function and reversibility characterize chronic asthma. The conventional therapy is targeted to control the disease without targeting the loss of lung function or reversibility. In a prospective real-world observation of long-term use of add-on doxycycline as a matrix-metalloproteinase inhibitor, we documented significant improvement in lung function with possible reversal of remodeling. BACKGROUND: Chronic asthma shows progressive decline in lung function with reduction or even loss of reversibility secondary to remodeling. A set of endopeptidase enzymes known as matrix metalloproteinases are intimately related to the pathogenesis of asthma and remodeling. The inhibition of matrix metalloproteinases is recognized as a prospective way of treating asthma and its corresponding structural remodeling. METHODS: In a randomized, prospective, real-world study, we have observed the change in lung function (spirometry) with an add-on of long-term doxycycline to standard asthma therapy as per the Global Initiative for Asthma guidelines in a small asthmatic population. The change in terms of forced expiratory volume (FEV(1)), forced vital capacity (FVC), percent of FEV(1) (FEV(1)%), and forced expiratory flow (FEF(25-75)) were noted following variable duration of doxycycline therapy. RESULTS: There has been a global improvement in all the parameters in all the six patients suggesting improvement in obstruction, and reduction in air trapping following a treatment of add-on doxycycline for a mean duration of 162.83 ± 83.07 days. Of the changes seen, the post bronchodilator FEV(1), the FVC, and the FEF(25-75) showed significant improvements with the P-value set at 0.004, 0.054, and 0.031, respectively. There was also evidence of the reversal of remodeling from the improvement in the FEV(1)/FVC ratio. Moreover there was a greater than expected improvement of pre-bronchodilator FEV(1) after treatment that far surpassed the initial post-bronchodialator FEV(1) value. Even after such a change, there were presences of some reversibility suggesting room for further improvement. CONCLUSION: The results suggest significant improvements in the obstructive parameters used to evaluate asthma, with possible reversal of remodeling evident in chronic asthmatics when treated with doxycycline in addition to standard therapies. This observation needs further scientific validation.

Left ventricular diastolic dysfunction in COPD may manifest myocardial ischemia.

BACKGROUND: Left ventricular diastolic dysfunction (LVDD) is observed frequently in advanced COPD and it appears unrelated to the co-presence of its common risk factors as hypertension, diabetes, ischemic heart disease, etc. The patho-physiology of this association is yet unclear. We postulated that ischemia not apparent in the routine clinical evaluation could be the cause of such LVDD. METHOD: Advanced COPD (GOLD III & IV) patients being excluded of concomitant presence of hypertension, diabetes, ischemic heart disease, and hypothyroidism by conventional evaluations were looked for the presence of LVDD by tissue Doppler echocardiography. The subjects having LVDD were further evaluated with 99(m)Tc MIBI stress myocardial perfusion imaging to detect the presence of ischemia. RESULTS: 7 out of 14 patients of advanced COPD sufferers without any known risk factors for LVDD had reversible perfusion defect in the stress perfusion imaging predominantly involving the inferior wall myocardium (71.43%). Most of the defects, though significant, were not picked up by stress ECG. CONCLUSION: Reversible ischemic defects are quite common (50%) in advanced COPD patients with LVDD without the presence of common risk factors. This association needs further evaluation.

Prevalence of osteoporosis and osteopenia in advanced chronic obstructive pulmonary disease patients.

BACKGROUND: Reduction of bone mineral density (BMD) is a known and established phenomenon in chronic obstructive pulmonary disease (COPD). However, there have been no data regarding osteoporosis/osteopenia in COPD patients in India. AIM: To look for the degree and frequency of osteoporosis/osteopenia in our OPD patients being diagnosed as COPD. MATERIALS AND METHODS: Thirty-seven randomly selected patients with COPD were assessed for BMD with commercially available ultrasound bone densitometer (HOLOGIC SAHARA) in a pulmonary OPD. Some cofactors for reduced BMD were also noted. RESULTS: Out of the 37 COPD (all belonging to the GOLD III/IV category) patients studied, the BMD was found to be normal in 10 (27%) patients, while 27 (73%) patients were found to have osteopenia/osteoporosis [19 (51.35%) and 8 (21.62%) patients having osteopenia and osteoporosis, respectively]. CONCLUSION: Frequency of osteoporosis and osteopenia was found to be very high (73%) in our population of advanced COPD. The data suggest a need for further in-depth study regarding the issue.

Treatment of asthma: Identification of the practice behavior and the deviation from the guideline recommendations.

BACKGROUND: Despite an exponential development of the understanding of the disease with availability of good therapy and feasibility of good control along with availability of globally accepted guidelines, there remains a significant gap between the guidelines and prevailing practice behavior for treating asthma all over the globe. This perhaps stands as the single most deterrent factor for good asthma care worldwide. The objective of the study is to analyze the asthma prescriptions to find out the available status of the practice behaviour and the deviations from the guideline in asthma practice. MATERIALS AND METHODS: The asthma prescriptions of the referred patients presenting to the OPD services of the IPCR, Kolkata were photocopied and collected. They were further analyzed based on the available information upon a format being prepared on four major areas as qualifications, clinical recording habit, practice of evaluating patients, and treatment habit that stands apparent from the prescribed medications. The doctors were divided into three categories as a) MBBS, b) MD/DNB (medicine and respiratory medicine), and c) DM (non respiratory sub-specialities) and statistical analysis has been performed comparing the three groups as per the performance in the four pre-decided areas. RESULTS: All the groups fall short of any guideline or text of asthma care in all the areas involved. CONCLUSION: The practice behaviour of our doctors for asthma care appears deficient in several areas and seems far from guideline recommendations. This needs further evaluation and adoption of appropriate interventions.

The role of long-term doxycycline in patients of idiopathic pulmonaryfibrosis: The results of an open prospective trial.

OBJECTIVE: To evaluate the effect of long term use of doxycycline in IPF patients. MATERIALS AND METHODS: Patients of IPF, selected randomly from out patient services and diagnosed on the basis of HRCT chest, were put on doxycycline in an open prospective trial. They were followed up with monitoring of subjective well being along with measurement of pulse rate and arterial oxygen saturation at rest and after a fixed and certain exercise, forced vital capacity, six minutes walk test, St Georges Respiratory questionnaire, and serial chest X-rays. RESULTS: Out of seven patients put on doxycycline, six of them continued the drug for a mean period of 531.43 (+/- 328.88 days). All the patients tolerated the drug well and had shown uniform subjective and overall objective improvement in all the parameters concerned; the change in the radiological parameter being statistically significant. CONCLUSION: Doxycycline merits an appropriate clinical trial in the management of idiopathic pulmonary fibrosis. This widely used and relatively safe drug can add a new dimension to the therapeutic regimen. However, further in-depth studies will be required to evaluate its role in the management of IPF.