Poly(para toluene sulphonic acid) and gold nanoparticles modified glassy carbon electrode for simultaneous voltammetric sensing of xanthine and hypoxanthine.

A voltammetric sensor has been developed for the individual as well as simultaneous determination of xanthine (XA) and hypoxanthine (HX) based on an electroactive-polymerised layer of para toluene sulphonic acid and gold nanoparticles composite modified glassy carbon electrode ([p(PTSA)]/AuNPs/GCE)]. Under optimized conditions, an enhancement in the oxidation currents with well-separated and well-resolved peak position and a lower shift in the peak potentials were observed. By square wave voltammetry, the simultaneous determinations of XA and HX were achieved in the linear ranges 6.00 × 10-4 M to 3.00 × 10-6 M and 5.00 × 10-4 M to 1.00 × 10-5 M with detection limits of 4.09 × 10-7 M and 4.10 × 10-7 M, respectively. The mechanistic aspects were unveiled from linear sweep voltammetric studies and found that the electrode processes were diffusion-controlled. Finally, the sensor was successfully employed for the simultaneous determination of spiked amount of XA and HX in synthetic urine and serum samples.

A rare presentation of antisynthetase syndrome requiring intensive care in the midst of a COVID wave.

A 24-year-old female with pneumonia two months prior presented with fever, cough, and worsening dyspnoea in the midst of a COVID-19 spike. Her initial episode was treated as COVID-19 pneumonia. On presentation, her chest computed tomography was suggestive of bilateral lower zone organising pneumonia with mild fibrosis and was attributed to post-COVID sequelae with an infective exacerbation. Oral steroids and antibiotics were administered, following which she had initial improvement and then subsequent deterioration requiring intensive care unit (ICU) care. A detailed clinical examination (in-person and virtually) at this point revealed the presence of pigmented rashes over the knuckles and weakness of hip muscles. Laboratory work showed elevated creatine kinase levels and positive anti-Ro and anti-Jo1 antibodies, which pointed to a diagnosis of antisynthetase syndrome. Unique attributes of this case include younger age of presentation in an atypical ethnic group, which are possibly incited by COVID-19 infection in the peak of a COVID-19 wave. The work-up, diagnosis, and initial management of this patient were carried out through a hybrid ICU model, which functioned as a traditional ICU in the day and a tele-ICU at night with an appropriate network of subspecialists including rheumatologists consulting, thus highlighting a collaborative model in a low-resource setting capable of managing rare cases even in the midst of increasing critical care needs during the pandemic.

Tannic Acid Capped Copper Nanoclusters as a Cost-Effective Fluorescence Probe for Hemoglobin Determination.

For the first time, we report on a copper nanoclusters based fluorescence sensor for hemoglobin (Hgb). The aggregation-induced quenching of tannic acid capped copper nanoclusters' (TACuNCs) fluorescence by a Hgb-H2O2 mixture that mimics the Fenton's reagent is used here for the selective determination of Hgb. It is possible to effectively determine Hgb using this sensitive and cost-effective sensor in the linear range of 5.0 × 10-8 to 4.0 × 10-9 M with a detection limit of 5.6 × 10-10 M. The practical utility of the sensor is evident from the good recovery values obtained from Hgb spiked with artificial blood serum.

Simple and Cost-effective "Turn-on" Fluorescence Sensor for the Determination of Xanthine.

A simple and selective 'turn-on' fluorescence sensor have been developed for the determination of xanthine (XA) based on glutathione (GSH) capped copper nanoclusters (CuNCs) as the fluorescent probe. The proposed sensor possess several advantages such as sensitivity, short analysis time and requires no sample pretreatment. The conditions for the performances of the sensor have been optimized and good linear relationship was obtained between concentration and relative fluorescence intensity in the concentration range 9.0[Formula: see text]10-3 M to 8.0[Formula: see text]10-5 M with a detection limit 6.0[Formula: see text]10-6 M. The mechanism behind the fluorescence enhancement may be ascribed to the binding of XA on the surface of GSH CuNCs. The sensor have been successfully applied to determine XA in spiked physiological samples.

A Simple and Cost Effective Turn off Fluorescence Sensor for Biliverdin and Bilirubin Based on L-Cysteine Modulated Copper Nanoclusters.

The present article reports the efficiency of L-cysteine modulated copper nanoclusters (L-cys-CuNCs) as a fluorescent probe for the selective determination of naturally occurring bile pigments biliverdin (BVD) and bilirubin (BLR). These pigments were found to quench the fluorescence of L-cys-CuNCs through static processes. Under optimized conditions, the proposed strategy permitted the quantification of BVD and BLR in the range 4.00 × 10-5 to 5.00 × 10-7M and 1.00×10-5 to 1.00×10-6 M respectively with limits of detection 2.33 × 10-7M and 2.29 × 10-7 M. The practical utility of the developed sensor have been investigated in spiked blood and urine samples.

Antibiotic Prescription Practices for Surgical Prophylaxis in India: An Observational Study.

Perioperative prophylactic antibiotics following surgeries have been shown to reduce surgical site infections, and their administration is common practice. Despite clear guidelines regarding this being set forth by the Infectious Disease Society of America (IDSA), adherence to them is yet to translate to common practice in many parts of the world. A retrospective chart review of 409 patients who underwent elective surgeries over a period of 7 months at three different hospitals in India was performed. In-hospital antibiotic prescriptions of these patients were examined for any apparent inappropriateness (use of antibiotics with coverage broader than the target microbes and use of antibiotics with overlapping spectrum of target microbes). Four hundred ninety-five (48.9%) of the 1,012 patient intensive care unit (ICU) days had apparent inappropriateness in the choice of their prophylactic antibiotics and only 3.2% of the antibiotic units used were in accordance with the present IDSA guidelines. Injudicious use of broad-spectrum antibiotics for surgical prophylaxis is prevalent in low- and middle-income countries such as India. This poses the risk of emergence of resistant microorganisms in these areas and their potential spread across the borders. There is an acute need for diligent antibiotic stewardship programs in these areas to curb such practices.

Interaction of tetracycline with l-cysteine functionalized CdS quantum dots - Fundamentals and sensing application.

The present paper reports l-cysteine functionalized CdS quantum dots (QDs) as a simple and highly selective turn-off fluorescence sensor for the determination of tetracycline (TET). The unauthorized use of TET may pose serious health hazards in human beings and hence the detection and determination has become very essential. In this regard, we have developed a sensor that enable the quantification of TET in the range 6.00 × 10-4 M to 1.50 × 10-5 M with a limit of detection 7.78 × 10-6 M, under optimized conditions. Steady state and time resolved fluorescence spectroscopic studies were used for investigating the mechanism of quenching and was found to be a combination of static and dynamic processes. The analytical application of the proposed sensor was investigated in pharmaceutical formulation.