Randomized controlled trial to evaluate the rate of successful neonatal endotracheal intubation performed with a stylet versus without a stylet.

INTRODUCTION: Neonates in intensive care units often require endotracheal intubation and mechanical ventilation. During this intubation procedure, a stylet is frequently used along with an endotracheal tube. Despite the widespread use of a stylet, it is still not known whether its use increases the intubation success rate. This study examined the association between stylet use and the intubation success rate in surgical neonates. METHODOLOGY: This single-center study was conducted between December 2021 and December 2022 in the Neonatal surgical intensive care unit of a tertiary care center in Northern India. Infants were randomized to have the endotracheal intubation procedure performed using either an endotracheal tube alone or with a stylet. The primary outcome of the study was to assess the successful first-attempt neonatal endotracheal intubation rate with and without using a stylet. Apart from the rate of successful intubation, the duration of the intubation and complications during the intubation procedures as measured by bradycardia, desaturation episodes, and local trauma were also recorded. Both groups were thus compared on above mentioned outcomes. RESULTS: The total number of neonates enrolled were 200, and the overall success rate (81% in the stylet group vs. 73% in the non-stylet group) was not statistically significant. Intubation time was however less, when stylet was used (16.2 ± 4.3 vs. 17.5 ± 5.0 s, p = .046). When the endotracheal tube size was 3 or less, the success rate was substantially higher in the stylet group (80%) than the non-stylet group (63%), p = .03. No statistical difference was recorded for bleeding and local trauma, though the esophageal intubation rate was higher when intubation was attempted without the stylet. CONCLUSION: Endotracheal intubation using a stylet did not significantly improve the success rate of the procedure, however, intubation time significantly varied between groups and in different conditions. The rigidity and curvature provided by the stylet may facilitate the process of intubation when smaller caliber endotracheal tubes are used.

Additional Bicarbonate Infusion Complements WHO Rehydration Therapy in Children with Acute Diarrhea and Severe Dehydration Presenting with Severe Non-anion Gap Metabolic Acidemia: An Open Label Randomized Trial.

OBJECTIVES: To assess the efficacy and safety of bicarbonate infusion in children with Acute Diarrhea and Severe Dehydration (ADSD) having severe Non-Anion Gap Metabolic Acidemia (sNAGMA). METHODS: Children (aged 1-144 mo) with ADSD and sNAGMA (pH ≤7.2 and/or serum bicarbonate ≤15 mEq/L) were enrolled in an open-label randomized design. Controls (n = 25) received WHO-recommended rehydration therapy with Ringer Lactate, while intervention group (n = 25) received additional bicarbonate deficit correction. Primary outcome was time taken to resolve metabolic acidemia (pH >7.30 and/or bicarbonate >15 mEq/L). Secondary outcome measures were adverse outcome [composite of pediatric intensive care unit (PICU) transfer and deaths], acute care area free days in 5 d (ACAFD5), hospital stay, and adverse effects. RESULTS: Time taken to resolve metabolic acidemia was significantly lesser with intervention [median (IQR); 8 h (4, 12) vs. 12 h (8, 24); p = 0.0067]. Intervention led to acidemia resolution in significantly more children by 8 h and 16 h (17/25 vs. 9/25, p = 0.035 and 23/25 vs. 17/24, p = 0.018, respectively). Patients with fluid refractory shock needed lesser inotropes in intervention group [median Vasoactive Inotrope Score (VIS), 10.5 vs. 34]. Intervention led to significantly lesser adverse outcome (0/25 vs. 5/25, p = 0.049), and noticeably more ACAFD5 [median (IQR); 2 (1, 2) vs. 1 (1, 2); p = 0.12]. Two patients died in the control group while none in the intervention group. No adverse effect was documented. CONCLUSIONS: Additional calculated dose of bicarbonate infusion led to significantly early resolution of metabolic acidemia, lesser utilization of critical care facilities, and lesser adverse outcome in children with ADSD and sNAGMA, compared to standard therapy, with no adverse effect.

Association between intraoperative anatomical variation and histopathological parameters in cases of ureteropelvic junction obstruction in children: A cross-sectional study.

Introduction: The intraoperative anatomical findings (IOAF) of all ureteropelvic junction obstruction (UPJO) cases are not identical. Moreover, there is also controversy in the literature regarding histopathological (HP) findings in cases of UPJO. In the present study, we evaluated different IOAF and assessed their association with specific HP parameters. Materials and Methods: This was a cross-sectional study set-up, which was carried out in a tertiary care centre. Children with UPJO who underwent surgery between 2017 and 2020 were enrolled. The following IOAF were noted: Type of pelvis (extrarenal or intrarenal), insertion of the ureter (high or normal), presence of lower pole crossing vessel (CV), negotiation of UPJ segment with double J stent (3 Fr) and length of internal narrowing (LIN) at UPJ. The resected segment of UPJ was assessed at three levels (pelvis, UPJ and ureter) for various HP parameters including fibrosis, oedema, inflammation and smooth muscle hypertrophy (SMH). Results: Thirty-nine children were included in the study with a mean age of 31 months. The summary statistics of IOAF were intrarenal pelvis in 5 cases, high insertion of the ureter (HIU) in 9, CV in 6, negotiable UPJ in 23, and 16 cases showed LIN >1 cm. All cases showed SMH at the pelvis region and SMH with fibrosis at the UPJ region. At the pelvis region, there was an association between (1) HIU with oedema and chronic inflammation (CIF), (2) CV with CIF and (3) LIN with CIF and SMH. At the UPJ region, there was an association between (1) CV and negotiable UPJ with less fibrosis and (2) LIN with SMH. At the ureteric end, CV showed an association with less fibrosis and more CIF. Conclusion: All UPJO cases have some common HP findings. Although, some particular IOAF, i.e., presence of CV, negotiable UPJ, HIU and LIN showed association with specific HP parameters.

Gum Arabic-mediated liquid exfoliation of transition metal dichalcogenides as photothermic anti-breast cancer candidates.

Transition metal dichalcogenides (TMDs) have gained considerable attention for a broad range of applications, including cancer therapy. Production of TMD nanosheets using liquid exfoliation provides an inexpensive and facile route to achieve high yields. In this study, we developed TMD nanosheets using gum arabic as an exfoliating and stabilizing agent. Different types of TMDs, including MoS2, WS2, MoSe2, and WSe2 nanosheets, were produced using gum arabic and were characterized physicochemically. The developed gum arabic TMD nanosheets exhibited a remarkable photothermal absorption capacity in the near-infrared (NIR) region (808 nm and 1 W⋅cm-2). The drug doxorubicin was loaded on the gum arabic-MoSe2 nanosheets (Dox-G-MoSe2), and the anticancer activity was evaluated using MDA-MB-231 cells and a water-soluble tetrazolium salt (WST-1) assay, live and dead cell assays, and flow cytometry. Dox-G-MoSe2 significantly inhibited MDA-MB-231 cancer cell proliferation under the illumination of an NIR laser at 808 nm. These results indicate that Dox-G-MoSe2 is a potentially valuable biomaterial for breast cancer therapy.

A dose escalated fiducial marker-based image guided radical radiotherapy in locally advanced prostate cancers: A single institute experience from India.

Purpose: Image guided radiotherapy (IGRT) is one of the most commonly used treatment in LAPC. Dose escalation >74 Gy has shown to improve the biochemical control and freedom from failure rate in LAPC.We started treating LAPC patients with dose escalated IGRT in our institute since 2008. We did a retrospective analysis to see the biochemical relapse-free survival, cancer-specific survival, and bladder and rectal toxicity. Methods: A total of 50 consecutive prostate cancer patients were treated with dose escalated IGRT between January 2008 to Dec 2013. Out of these, 37 patients of LAPC were analyzed and their medical records were retrieved. All were biopsy proven adenocarcinoma of prostate with D'Amico high risk category (PSA >20 ng/mL or Gleason score (GS) >7 or T2c-T4). Three gold fiducial markers were placed in the prostate. Patients were immobilized in supine position with either ankle or knee rest. Partial bladder filling and rectum emptying protocol was followed. Clinical target volume (CTV) segmentation was done according to EORTC recommendation. Population based PTV expansion from CTV of 10 mm (cranio-caudal), 10 mm (medio-lateral), 10 mm (anterior) and 5 mm (posterior) was given. In patients with radiologically enlarged pelvic lymph node, whole pelvis intensity modulated radiation therapy (IMRT) to a dose of 50.4 Gy/28# followed by prostatic boost 26Gy/13# by IMRT using image guidance. Rest of the patients received prostate only RT to a dose of 76Gy/38# by IGRT. Daily On board KV images were taken and 2D-2D fiducial marker matching was done and shifts were applied on machine before treatment. Biochemical relapse was defined as per Phoenix definition (nadir + 2 ng/mL). Radiation Therapy Oncology Group (RTOG) toxicity grading system was used to document acute and late toxicity. Results: Median age of patients was 66 years. Median pre-treatment PSA was 22 ng/mL. Thirty patients (81%) had T3/T4 lesions and nodal metastasis was seen in 11 (30%). Median GS was 8. Median radiotherapy dose was 76 Gy. Imaging before radiation delivery was done in 19(51%) patients and 100% in 14 (38%) patients. With a median follow up of 6.5 years, 5-year biochemical relapse-free survival (bRFS) and cancer-specific survival (CSS) was 66% and 79% respectively. Mean bRFS and CSS were 71 months and 83 months however Median bRFS and CSS were not reached. Distant metastasis was seen in 8 (22%). RTOG grade III bladder and rectal toxicity was seen in 2 (6%) and 2 (6%) patients respectively. Conclusion: Dose escalated IGRT with fiducial marker positional verification for LAPC is doable in Indian setup provided more emphasis given on daily on-board imaging with rigorous bladder filling and rectal emptying protocol. Long term follow up is needed to assess the effect on distant disease-free survival and CSS.

Determination of lysophosphatidylcholine using peroxidase-mimic PVP/PtRu nanozyme.

Lysophosphatidylcholine (LPC) can be used as a biomarker for diseases such as cancer, diabetes, atherosclerosis, and sepsis. In this study, we demonstrated the ability of nanozymes to displace the natural derived enzyme in enzyme-based assays for the measurement of LPC. Synthesized polyvinylpyrrolidone-stabilized platinum-ruthenium nanozymes (PVP/PtRu NZs) had a uniform size of 2.48 ± 0.24 nm and superb peroxidase-mimicking activity. We demonstrated that the nanozymes had high activity over a wide pH and temperature range and high stability after long-term storage. The LPC concentration could be accurately analyzed through the absorbance and fluorescence signals generated by the peroxidation reaction using the synthesized nanozyme with substrates such as 3,3',5,5'-tetramethylbenzidine (TMB) and 10-acetyl-3,7-dihydroxyphenoxazine (Ampliflu™ Red). LPC at a concentration of 0-400 µM was used for the analysis, and the coefficient of determination (R2) was 0.977, and the limit of detection (LOD) was 23.1 µM by colorimetric assay. In the fluorometric assay, the R2 was 0.999, and the LOD was 8.97 µM. The spiked recovery values for the determination of LPC concentration in human serum samples were 102-115%. Based on these results, we declared that PVP/PtRu NZs had an ability comparable to that of the native enzyme horseradish peroxidase (HRP) in the enzyme-based LPC detection method.

A phase II study of neoadjuvant chemotherapy followed by organ preservation in patients with muscle-invasive bladder cancer.

Objective: Conservative approaches in muscle-invasive bladder cancer (MIBC) have been evolved to avoid aggressive surgery, but are limited to elderly, frail, and patients medically unfit for surgery. Our study aimed to assess the response rate of neoadjuvant chemotherapy (NACT) before radiotherapy (RT) in MIBC patients. Methods: Forty patients with urothelial carcinoma of stage T2-T4a, N0, M0 were enrolled between November 2013 and November 2015, and treated with three cycles of NACT with gemcitabine-cisplatin. Post-NACT response was assessed using Response Evaluation Criteria in Solid Tumors (RECIST) criteria. Patients who achieved complete response (CR) and partial response (PR) >50% were treated with radical RT, and those who had PR <50%, stable disease (SD), and progressive disease (PD) underwent radical cystectomy (RC). Survival analysis was done with Kaplan-Meier method and point-to-time events were analyzed with Cox-proportional hazards regression model. Results: After NACT, 35 (87.5%) patients achieved either PR >50% or CR, and were treated with RT. Five (12.5%) patients who had PR <50%, SD, or PD underwent RC. All patients who received radiation showed CR after 6 weeks. Median follow-up was 43 months (range: 10-66 months) and median overall survival (OS) was not reached. Three-year OS, local control, and disease-free survival were 70.1%, 60.9%, 50.6%, respectively, and 50% of patients preserved their functioning bladder. Three-year OS rate was 88.9% in patients who achieved CR to NACT, 73.1% in patients with PR ≥50% and 40% in patients with PR <50%. Conclusion: NACT followed by RT provides a high probability of local response with bladder preservation in CR patients. Appropriate use of this treatment regimen in carefully selected patients may omit the need for morbid surgery.

Mesoporous platinum nanoparticles as a peroxidase mimic for the highly sensitive determination of C-reactive protein.

The generation of a mesoporous structure in platinum nanoparticles can effectively enhance physical and chemical properties. In this study, mesoporous platinum nanoparticles (MPNs) were synthesized by a soft template-mediated one-pot chemical method. To develop a mesoporous structure, Pluronic F-127 was employed. The Pluronic F-127 surfactant forms self-assembled micelles, and the micelles act as the pore-directing agents in the synthesis of nanoparticles. Scanning electron microscopy results revealed that the MPN had a uniform size of 70 nm on average and a distinct mesoporous structure. The development of a concave mesoporous structure on the surface of the MPNs can increase the surface area and facilitate the efficient transport of reactants. The synthesized MPNs exhibited peroxidase-like activity. Furthermore, the MPNs showed excellent catalytic efficiency compared to HRP, due to the high surface area derived from the presence of the mesoporous structure. The peroxidase-like MPNs were applied to the enzyme-linked immunosorbent assay (ELISA) of C-reactive protein (CRP). The MPN-based ELISA exhibited sensitive CRP detection in the range from 0.24 to 7.8 ng/mL with a detection limit of 0.13 ng/mL. Moreover, the recoveries of the CRP concentrations in spiked human serum were 98.6% and 102%. These results demonstrate that as a peroxidase mimic, the MPNs can replace the natural enzymes in conventional ELISA for sensitive CRP detection.

Implications of left atrial enlargement and patent foramen ovale creation on early surgical outcomes in patients with total anomalous pulmonary venous connection.

INTRODUCTION: In patients with total anomalous pulmonary venous connection (TAPVC), left atrium (LA) is small and suprasystemic pulmonary artery (PA) pressures may be present in some patients. In our study, we studied the relationship between surgical LA enlargement and patent foramen ovale (PFO) creation separately on the outcomes of patients with TAPVC. MATERIALS AND METHODS: Out of the 130 patients operated in our institute between January 2014 and December 2020, LA was enlarged in 60 patients. LA enlargement was done using a larger patch for atrial septal defect (ASD) closure. Thus, the LA volume was increased by shifting the patch towards the right atrium (RA). Suprasystemic or high PA pressures were present in 60 patients. In 33 patients, PFO was created. Early surgical outcomes were determined on the basis of vasoactive inotropic score (VIS), hours of ventilation, hours of inotropic support, intensive care unit (ICU) stay, and hospital stay. RESULT: Between the LA enlarged and nonenlarged group there was statistically significant less VIS score (18 [13-27.5] vs. 24 [18-30], p value .019), hours of ventilation (23 [16-46.5] vs. 26 [18-60], p value .039), hours of inotropic support (45.5 [30-72] vs. 55 [38-84], p value .038), and ICU stay (7 [5-9] vs. 8 [7-10] p value .0352) and statistically nonsignificant less hospital stay (11.5 [9-13] vs. 12 [9-14], p value .424). In patients with preoperative suprasystemic or high PA pressures, there was a statistically significant less VIS score (16 [11-23.5] vs. 18 [13-25], p value .044), hours of ventilation (20 [14-37] vs. 22 [18-39], p value .038), hours of inotropic support (34 [29.5-71] vs. 38 [30-78], p value .042), and hospital stay (9 [5-12] vs. 11 [9-14], p value .038) and statistically nonsignificant less ICU stay (7 [5.5-9] vs. 7 [6-9], p value .886) in the group with a PFO with respect to the other group in which no PFO was created. CONCLUSION: In patients with TAPVC, LA can be enlarged by using a large ASD patch and thus shifting the septum towards RA. Early surgical outcomes were improved with LA enlargement. In patients with suprasystemic or high PA pressures, leaving a PFO improved the postoperative outcomes.

PVP-stabilized PtRu nanozymes with peroxidase-like activity and its application for colorimetric and fluorometric glucose detection.

Nanozymes have significant advantages over natural enzymes. The intrinsic peroxidase-like activity of Pt-based nanomaterials can be enhanced by alloying with other transition metals, such as Ru, that have great catalytic activity. In this study, we used polyvinylpyrrolidone (PVP) to synthesize well-dispersed and homogeneous nanostructures. PVP-stabilized Pt-Ru nanozymes (PVP/PtRu NZs) were synthesized and characterized. The PVP/PtRu NZs had an average size of 3.54 ±â€¯0.84 nm and exhibited an intense peroxidase-like activity. The PVP/PtRu NZs were used as peroxidase mimics for colorimetric and fluorometric glucose determination by the glucose oxidase and PVP/PtRu NZs cascade reaction. In the colorimetric assay, the linearly detectable range was 0.25-3.0 mM, with an R2 and limit of detection (LOD) of 0.988 and 138 µM, respectively. In the fluorometric assay, a linear relationship was found when the glucose concentration was between 5.0 and 300 µM (R2 = 0.997), with an LOD of 1.11 µM. Compared to the colorimetric assay, the fluorometric assay had greater sensitivity and a lower detection limit for the determination of glucose. Moreover, the PVP/PtRu NZs had high storage stability over a month and great recovery values in human serum and artificial urine, with a range of 94-106 %. From these results, PVP/PtRu NZs are expected to be used as promising peroxidase mimics in various fields such as biosensing, pharmaceutical processing, and the food industry.

Functionalized ultra-fine bimetallic PtRu alloy nanoparticle with high peroxidase-mimicking activity for rapid and sensitive colorimetric quantification of C-reactive protein.

The in situ synthesis is reported of citric acid-functionalized ultra-fine bimetallic PtRu alloy nanoparticles (CA@PtRu ANPs) through a simple one-pot wet chemical method. The cost-efficient CA@PtRu ANPs with an average diameter of 3.2 nm revealed to have enhanced surface area, peroxidase-like activity, high stability, and adequate availability of functional groups to bind biomolecules. Along with nanoparticle surface area, the surface charge has also significantly affected the peroxidase-like activity and the colloidal suspension stability. As an excellent immobilization matrix and peroxidase mimic, the CA@PtRu ANPs were utilized to develop non-enzymatic colorimetric immunoassay for rapid, selective, and sensitive quantification of C-reactive protein (CRP) biomarkers. In this immunoassay, CA@PtRu ANPs serve as enzyme mimic that significantly amplifies the color signals, and amine-functionalized silica-coated magnetic microbeads (APTES/SiO2@Fe3O4) act as CRP-recognizing capture probes. The absorbance curves of colorimetric immunoassay were measured in wavelengths between 550 and 750 nm, and the maximum absorbance at 652 nm was used to establish a linear relationship between absorbance and CRP concentrations. The developed colorimetric immunoassay showed rapid and sensitive quantification of CRP levels from 0.01 to 180 µg mL-1 with a LOD of 0.01 µg mL-1. Moreover, the mean recovery of CRP from spiked human serum samples lies between 97 and 109% (n = 3), which indicates that the proposed nanozyme-linked immunoassay has the potential to be used in rapid point-of-care applications.

Mucosal coaptation technique for early urinary continence after robot-assisted radical prostatectomy: a comparative exploratory study.

INTRODUCTION: Urinary incontinence is a troublesome complication following radical prostatectomy. Various robot-assisted radical prostatectomy (RARP). We describe our technique (Santosh-PGI) of urethral and urinary bladder mucosa coaptation for early continence following RARP. MATERIAL AND METHODS: We performed a prospective comparative study of patients planned for RARP between July 2018 and December 2019 at our centre. A total of 40 patients were enrolled in the study protocol. Following prostatectomy, patients were alternatively assigned into two groups. In one group, urethral and urinary bladder coaptation sutures were placed in a purse string manner using 3-0 Monocryl sutures and none in the another group. All patients underwent standard end to end vesico-urethral anastomosis as described by Van Velthoven. The urinary catheter was removed on day 10 after surgery. All patients were evaluated on day 1, 30 and 90 after catheter removal. RESULTS: The two groups, each with 20 patients, were comparable in terms of age, clinical staging and D'Amico risk classification. The operative time, blood loss and surgical margin positivity were comparable. Following catheter removal, 75% of patients in Group A (Mucosal coaptation) and 50% in Group B (Standard technique) were continent (p = 0.264). At 30 and 90 days, 90% and 95% in Group A and 60% and 80% in Group B reported continence respectively (p-0.078). Four patients in group B reported bothersome incontinence at 90 days follow-up. CONCLUSIONS: Urethral and urinary bladder mucosal coaptation is a simple innovative technique for early continence following RARP.

Comparison of Ventilator-free Days at 14 and 28 days as a Clinical Trial Outcome in Low- and Middle-income Countries.

AIMS AND OBJECTIVES: Reporting ventilator-free days (VFDs) with time frame of 28 days is a popular composite outcome measure (COM) in trials. However, early deaths and shorter pediatric intensive care unit (PICU) stay predominate in low- and middle-income countries (LMICs). A shorter time frame may reduce sample size required. We planned to compute sample size requirements for different effect sizes from datasets of previously conducted prospective studies for 28-day and 14-day time frames (VFD28 vs VFD14) to examine the hypothesis. MATERIALS AND METHODS: The VFD28 and VFD14 were defined. Datasets of five prospective studies from PICU of our hospital were analyzed to estimate sample sizes for target reductions of 1-9 days in VFDs and other COMs for the two time frames. Reconfirmation of results was done with datasets of two other studies from PICUs of two geographical extremes of the country. RESULTS: Time-to-event occurred within 14 days in majority of patients. Sample size required for VFD14 is about one-fifth to one-sixth of what is required for VFD28 for target reductions of 1-9 days for all the enrolled studies. The same was true for other COMs as well. The hypothesis was supported by datasets of two other studies used for reconfirmation. CONCLUSION: Choice of time frame for assessing VFDs and other COMs in clinical trials should be guided by the clinical context. A shorter time frame may be rewarding in terms of smaller sample size in the prevalent clinical setting of LMICs. Further confirmation with more datasets and prospective studies is desirable. HOW TO CITE THIS ARTICLE: Baranwal AK, Kumar MP, Gupta PK. Comparison of Ventilator-free Days at 14 and 28 days as a Clinical Trial Outcome in Low- and Middle-income Countries. Indian J Crit Care Med 2020;24(10):960-966.

Detection of Beijing strains of MDR M. tuberculosis and their association with drug resistance mutations in katG, rpoB, and embB genes.

BACKGROUND: Molecular epidemiological studies of Mycobacterium tuberculosis (MTB) are the core of current research to find out the association of the M. tuberculosis genotypes with its outbreak and transmission. The high prevalence of the Beijing genotype strain among multidrug resistance (MDR) TB has already been reported in various studies around India. The overall objective of this study was to detect the prevalence of Beijing genotype strains of MDR M. tuberculosis and their association with the clinical characteristics of TB patients. METHODS: In this study 381 M. tuberculosis clinical isolates were obtained from sputum samples from 2008 to 2014. The multiplex-PCR and Spoligotyping (n = 131) methods were used to investigate the prevalence of the Beijing genotype strain by targeting the Rv2820 gene and their association with drug resistance and clinical characteristics of TB patients. The drug susceptibility testing of first-line anti-TB drugs was performed by using the proportion method and MGIT960. A collection of isolates having Beijing and non-Beijing strains were also characterized to see if Beijing genotype strains had a higher rate of mutations at codons 516, 526 and 531 of the 81-bp region of the rpoB gene, codon 315 of the katG gene, and codon 306 of the embB gene. RESULTS: The sensitivities and specificities of multiplex-PCR assay compared to that of standard Spoligotyping was detected to be 100%. Further, we observe that the multi drug-resistance was significantly associated with Beijing genotype strains (p = 0.03) and a strong correlation between Beijing genotype strains and specific resistance mutations at the katG315, rpoB531, and embB306 codons (p = < 0.0001, < 0.0001 & 0.0014 respectively) was also found. CONCLUSIONS: This rapid, simple, and cost-effective multiplex PCR assay can effectively be used for monitoring the prevalence of Beijing genotype strains in low resource settings. Findings of this study may provide a scientific basis for the development of new diagnostic tools for detection and effective management of DR-TB in countries with a higher incidence rate of Beijing genotype strains.

Determination of glycated albumin using a Prussian blue nanozyme-based boronate affinity sandwich assay.

Nanozymes are effective substitutes for natural enzymes and offer multiple advantages. Here, synthesized Prussian blue nanoparticles (PBNPs) exhibited excellent peroxidase-like activity, catalyzing the oxidation of 3,5,3',5'-tetramethylbenzidine (TMB) in the presence of hydrogen peroxide within 1 min. Oxidized TMB (TMBox) underwent a color change from transparent to blue and then yellow by a stop solution. Moreover, the TMBox could be reduced on an indium tin oxide electrode, generating an electrochemical current, indicating that TMB can be used as a colorimetric and electrochemical indicator. The PBNPs modified with 3-aminophenylboronic acid (APBA) captured glycated albumin (GA) with a boronate affinity sandwich assay. As boronic acid binds to glycoproteins using cis-diol bonding, it can be used to detect GA. The APBA-modified PBNPs (PBBA) were involved with a sandwich complex formation and employed as nanozymes for the quantitative analysis of GA using colorimetric and electrochemical methods. Both methods showed strong linearities for different concentrations of GA. The results show that PBBA is a suitable alternative for natural enzymes and can be applied to sensitive determination of GA.

One-pot synthesized citric acid-modified bimetallic PtNi hollow nanospheres as peroxidase mimics for colorimetric detection of human serum albumin.

The combination of Pt with low-cost transition metal is an effective way to diminish the bulk utilization of costly Pt and to design new nanostructured materials with improved enzyme-like activity. In the present work, citric acid-functionalized platinum-nickel hollow nanospheres (CA@PtNi hNS) were synthesized through a simple one-pot wet chemical method, which involves the galvanic replacement reaction between the Ni nanoparticles and the Pt precursor that leads to the formation of hollow nanostructures. Transmission electron spectroscopic images revealed the uniformity of the CA@PtNi hNS, with an average diameter of 10.3 ± 2 nm. Moreover, zeta potential, FTIR, and XPS measurements confirmed the existence of citric acid in the CA@PtNi hNS. During synthesis, the use of citric acid not only facilitates monodispersity but also provides a negative surface charge (-11 mV) to the CA@PtNi hNS that electrostatically attracts the 3,3',5,5'-Tetramethylbenzidine (TMB) substrate. As-prepared CA@PtNi hNS possessed excellent peroxidase-like activity due to rich Pt surfaces, large surface area, and heterogeneous interaction between Pt and Ni atoms. Furthermore, a nanozyme-linked immunosorbent assay (NLISA) for human serum albumin (HSA) detection was developed by replacing the enzyme in a standard enzyme-linked immunosorbent assay with CA@PtNi hNS. The CA@PtNi hNS based-NLISA showed sensitive detection of HSA concentrations ranging from 0 to 400 ng mL-1 with a LOD of 0.19 ng mL-1 and an average of 112% recovery of HSA from the spiked human plasma samples. The outcomes of the present study confirm the applicability of CA@PtNi hNS as substitutes for natural enzymes.

Silver molybdate nanoparticles based immunosensor for the non-invasive detection of Interleukin-8 biomarker.

In this study, we report the silver molybdate nanoparticles (ß-Ag2MoO4 NPs) based non-invasive and sensitive electrochemical immunosensor for label-free detection of Interleukin-8 (IL-8) biomarker. The X-ray diffraction and Raman spectroscopy studies confirm the cubic spinel structures of ß-Ag2MoO4 NPs. High-resolution transmission electron microscopy study depicted average size of ß-Ag2MoO4 NPs as 27.15 nm. The cleaned indium tin oxide coated glass substrates were coated with spin-coated thin films of Ag2MoO4 NPs. These electrodes used for covalently immobilization of antibodies specific to IL-8 (Anti-IL-8) using EDC-NHS chemistry and unbound activated sites blocked by bovine serum albumin. Electrochemical response was obtained in the range of 1 fg mL-1 to 40 ng mL-1 and the sensitivity was found to be 7.03 µA ng-1mL cm-2 with LOD of 90 pg mL-1. Spiked samples prepared by human saliva were tested and found efficient detection with this immunoelectrode.

Intramacrophage Delivery of Dual Drug Loaded Nanoparticles for Effective Clearance of Mycobacterium tuberculosis.

The escalating global burden of tuberculosis necessitates radical strategies to curb its spread. In this study, rifampicin (RIF), a first line anti-tubercular antibiotic and curcumin (CUR), a promising antimycobacterial compound were co-encapsulated in polymeric nanoparticles to achieve intramacrophage delivery and improved Mycobacterium tuberculosis clearance. The dual loaded nanoparticles revealed average size ∼400 nm, low polydispersity and zeta potential of -26.89 ± 2.9 mV. Near complete release of both drugs from nanoparticles in artificial lysosomal fluid proposed drug release after macrophage internalisation. Nanoparticles were nontoxic to RAW 264.7 macrophages and aided 1.5-fold higher drug internalisation compared to free drugs. Enriched intracellular internalisation and lysosomal presence of nanoparticles was ascertained by confocal microscopy. Comparable minimum inhibitory concentration (MIC) of free RIF and CUR and nanoparticle encapsulated RIF and CUR confirmed retention of drug properties. High efficacy against Mycobacterium tuberculosis infected macrophages with RIF-CUR nanoparticles at 25× MIC (98.03 ± 2.5%), with complete clearance above 50× MIC suggests the dual loaded nanoparticles as a promising new nanosystem for tackling tuberculosis.

Pancreatic disease patients are at higher risk for Clostridium difficile infection compared to those with other co-morbidities.

BACKGROUND: Surveillance of Clostridium difficile infection (CDI) in patients with underlying diseases is important because use of prophylactic antibiotics makes them prone to CDI. Epidemiology of CDI in this high-risk population is poorly understood. A study was conducted to evaluate the impact of CDI in patients with specific underlying co-morbidities. METHOD: A total of 2036 patients, whose fecal samples were processed for C. difficile toxin A and B assay by ELISA formed the basis of study. Patients with underlying diseases were classified based on the organ/kind of disease as pancreatic (n = 340), renal (n = 408), hepatic (n = 245), malignant (n = 517) and miscellaneous disease (n = 526). Laboratory records of clinical and demographic details were reviewed. The association of CDI with age, gender, antibiotic receipt, clinical symptoms and underlying co-morbidities was analyzed. Variation in CDI cases based on age groups was also investigated. RESULT: Clostridium difficile toxin positivity was 21.6% in general, whereas it was 30.6% in the pancreatic, 17.9% in the renal, 19.6%, in the hepatic, 21.3% in the malignancy and 20.0% in the miscellaneous disease groups. Toxin positivity was the lowest (14.8%) for female gender under renal disease and the highest (31.8%) for patients aged 40 to < 60 years, under pancreatic disease. Bloody diarrhea was a significant predictor for C. difficile toxin positivity. C. difficile toxin status irrespective to the underlying diseases was neither dependent on gender, age-groups or the number of antibiotics used. Association between patients' gender, age and antibiotics receipt with underlying disease conditions, respective to C. difficile toxin status showed significance in relation to male gender (p < 0.05), age 40 to < 60 years (p = 0.03) and those receiving single (p = 0.09) or multiple antibiotics (p = 0.07). CONCLUSION: Pancreatic disease patients are at a higher risk for developing CDI, and particularly male gender, age 40 to < 60 years and those receiving antibiotics are at significant risk.

Polymeric curcumin nanoparticles by a facile in situ method for macrophage targeted delivery.

Targeting macrophages is a promising strategy for improved therapy of intracellular infections as macrophages exhibit rapid phagocytosis of particles >200 nm. Entrapment of Curcumin (CUR) in nanocarriers could provide bioenhancement and macrophage targeting. We present a simple and facile in situ nanoprecipitation approach for instantaneous and on-site generation of curcumin nanoparticles (ISCurNP). ISCurNP optimised by Box-Behnken design exhibited average size of 208.25 ± 7.55 nm and entrapment efficiency of 90.16 ± 1.17%. Differential scanning calorimetry and X-Ray diffraction confirmed amorphization of CUR in ISCurNP. Sustained release was observed over 72 hr in vitro at lysosomal pH 4.5. Rapid and high uptake in RAW 264.7 macrophages was confirmed by flow cytometry and high performance liquid chromatography. Confocal microscopy established localisation of ISCurNP in lysosomal compartment. The facile in situ nanoprecipitation method provides simple, scalable technology to enable macrophage targeted delivery of CUR, with great promise for improved therapy of intracellular infections.