Effect of lockdown amid second wave of COVID-19 on environmental noise scenario of the megacity Delhi, India.

This paper analyzes the impact of second wave of COVID-19 lockdown on environmental noise levels of 25 sites in Delhi city and compares the noise scenario during pre-lockdown, lockdown, and post-lockdown periods. The study utilized the noise monitoring data acquired from 25 real-time ambient noise monitoring stations, installed by the Delhi Pollution Control Committee, Delhi, at various sites throughout Delhi city. A significant reduction of up to 10 and 3 dB(A) in day and night equivalent noise levels, respectively, had been observed during the lockdown period as compared to the pre-lockdown and post-lockdown periods. The study also revealed that only nine sites, including four industrial and five commercial zone sites, complied with the ambient noise standards during lockdown period, and no silence or residential zone sites complied with the ambient noise standards even during the lockdown period. A roadmap for environmental noise management and control is suggested. The study also reports the community's perception toward the change in acoustic environment of Delhi city during the lockdown period by conducting an environmental noise perception survey. The present study should be helpful in devising noise control action plans and policy interventions for environmental noise management and control in the metropolitan city Delhi, India.

Impact of COVID-19 lockdown on ambient noise levels in seven metropolitan cities of India.

The paper analyzed the impact of lockdown on the ambient noise levels in the seventy sites in the seven major cities of India and ascertained the noise scenario in lockdown period, and on the Janta Curfew day in comparison to the pre-lock down period and year 2019 annual average values. It was observed that the majority of the noise monitoring sites exhibited a decrement in ambient day and night equivalent noise levels on the national Janta Curfew day and Lockdown period as compared with the normal working days attributed to the restricted social, economical, industrial, urbanization activity and reduced human mobility. A mixed pattern was observed at a few sites, wherein the ambient day and night equivalent noise levels during Janta curfew day and Lockdown period had been reported to be higher than that on the normal working days. The study depicts the noise scenario during the lockdown and pre-lockdown period for seventy sites in India and shall be instrumental in analyzing the consequences and implications of imposing lockdowns in future on the environmental noise pollution in Indian cities.

Anti-EGFR-resistant clones decay exponentially after progression: implications for anti-EGFR re-challenge.

BACKGROUND: Colorectal cancer (CRC) has been shown to acquire RAS and EGFR ectodomain mutations as mechanisms of resistance to epidermal growth factor receptor (EGFR) inhibition (anti-EGFR). After anti-EGFR withdrawal, RAS and EGFR mutant clones lack a growth advantage relative to other clones and decay; however, the kinetics of decay remain unclear. We sought to determine the kinetics of acquired RAS/EGFR mutations after discontinuation of anti-EGFR therapy. PATIENTS AND METHODS: We present the post-progression circulating tumor DNA (ctDNA) profiles of 135 patients with RAS/BRAF wild-type metastatic CRC treated with anti-EGFR who acquired RAS and/or EGFR mutations during therapy. Our validation cohort consisted of an external dataset of 73 patients with a ctDNA profile suggestive of prior anti-EGFR exposure and serial sampling. A separate retrospective cohort of 80 patients was used to evaluate overall response rate and progression free survival during re-challenge therapies. RESULTS: Our analysis showed that RAS and EGFR relative mutant allele frequency decays exponentially (r2=0.93 for RAS; r2=0.94 for EGFR) with a cumulative half-life of 4.4 months. We validated our findings using an external dataset of 73 patients with a ctDNA profile suggestive of prior anti-EGFR exposure and serial sampling, confirming exponential decay with an estimated half-life of 4.3 months. A separate retrospective cohort of 80 patients showed that patients had a higher overall response rate during re-challenge therapies after increasing time intervals, as predicted by our model. CONCLUSION: These results provide scientific support for anti-EGFR re-challenge and guide the optimal timing of re-challenge initiation.

Conduction block in immune-mediated neuropathy: paranodopathy versus axonopathy.

BACKGROUND AND PURPOSE: Conduction block is a pathognomonic feature of immune-mediated neuropathies. The aim of this study was to advance understanding of pathophysiology and conduction block in chronic inflammatory demyelinating polyneuropathy (CIDP) and multifocal motor neuropathy (MMN). METHODS: A multimodal approach was used, incorporating clinical phenotyping, neurophysiology, immunohistochemistry and structural assessments. RESULTS: Of 49 CIDP and 14 MMN patients, 25% and 79% had median nerve forearm block, respectively. Clinical scores were similar in CIDP patients with and without block. CIDP patients with median nerve block demonstrated markedly elevated thresholds and greater threshold changes in threshold electrotonus, whilst those without did not differ from healthy controls in electrotonus parameters. In contrast, MMN patients exhibited marked increases in superexcitability. Nerve size was similar in both CIDP groups at the site of axonal excitability. However, CIDP patients with block demonstrated more frequent paranodal serum binding to teased rat nerve fibres. In keeping with these findings, mathematical modelling of nerve excitability recordings in CIDP patients with block support the role of paranodal dysfunction and enhanced leakage of current between the node and internode. In contrast, changes in MMN probably resulted from a reduction in ion channel density along axons. CONCLUSIONS: The underlying pathologies in CIDP and MMN are distinct. Conduction block in CIDP is associated with paranodal dysfunction which may be antibody-mediated in a subset of patients. In contrast, MMN is characterized by channel dysfunction downstream from the site of block.

Antibacterial and antifungal activity of chitosan coated iron oxide nanoparticles.

BACKGROUND AND AIM: The emergence of resistance against antimicrobial agents has led to the development of more efficient agents and new techniques for treatment of various microbial infections. The aim of the present study is to determine the antibacterial and antifungal activity of bare and chitosan coated Fe3O4 nanoparticles (NPs) against five organisms, Escherichia coli (E. coli), Bacillus subtilis (B. subtilis), Candida albicans (C. albicans), Aspergillus niger (A. niger) and Fusarium solani (F. solani). METHODS: Fe3O4 NPs were synthesised by coprecipitation and surface coating was done by chitosan polymer to avoid agglomeration. The antimicrobial property of NPs was tested by agar well diffusion and analysed by measuring the diameter of the inhibition zone. RESULTS: Average particle size of Fe3O4 and chitosan coated Fe3O4 NPs was 10.4 ± 4.9 and 11.4 ± 5.2 nm, respectively. Mean diameter of inhibition zone of synthesised chitosan coated Fe3O4 NPs was in the range 14.5 to 18.5 mm. The effect of chitosan coated Iron oxide nanoparticles was F. solani/A. niger < C. albicans < E. coli/B. subtilis (p < 0.001). CONCLUSIONS: Chitosan coated Fe3O4 NPs are effective antimicrobial agents and so may be developed as a microbial resistant coating for biomedical devices.

Influence of protein tyrosine phosphatase gene (PTPN22) polymorphisms on rheumatic heart disease susceptibility in North Indian population.

This study was aimed to assess the association of Protein tyrosine phosphatase non-receptor22 (PTPN22) gene single nucleotide polymorphisms (SNPs) with rheumatic heart disease (RHD) susceptibility in 400 RHD patients and 300 controls. The PTPN22 polymorphisms (rs2476601, rs1217406 and rs3789609) were genotyped using Taqman probes (Applied Biosystems, Foster City, CA). Statistical analysis was performed by spss and haplotype analysis by snpstat. The frequencies of variant alleles were not different between controls and cases (rs2476601: 2.00% & 1.05%; rs1217406: 36.33% & 34.75%; and rs3789609: 38.17% & 40.00%, respectively]. However, G rs2476601 A rs1217406 T rs3789609 haplotype turned out to be a low risk factor for RHD (P = 0.0042) predisposition in females and adult patients. This study suggests PTPN22 haplotype may modulate the risk to RHD in North Indians.

Assessing the impact of irrigation treatments on thiram residual trends: correspondence with numerical modelling and field-scale experiments.

The present study was undertaken to study the trends of transport of thiram, a dithiocarbamate pesticide, at different time and depth in the fields under real field conditions for wheat crop. Numerical simulations were carried out by solving the coupled soil-water content movement and mass transport equations using HYDRUS- 1D. The supplementary data used for paramaterization of HYDRUS-1D comprise of irrigation treatments, climatic conditions, and soil characteristics. Results focus on the effects and influence of irrigation treatments on pesticide persistence and mobility. Modelling results were in good agreement with the experimentally determined thiram concentrations. Application of the model to measured field data of thiram movement indicates that the modelling approach can provide reliable and useful estimates of the mass flux of water and non-volatile pesticide in vadose zone. For policy-makers and planners, some regulation strategies are suggested for controlling inappropriate pesticide application under deficit irrigation or rain-fed conditions.

Morphometric analysis of epithelial thickness and blood vessels in different grades of oral submucous fibrosis.

BACKGROUND: Oral submucous fibrosis (OSF) is a common oral health problem in the Indian subcontinent. It is characterized by a juxtaepithelial inflammatory reaction followed by fibroelastic changes in the lamina propria. Traditionally, it is said to be associated with marked epidermal atrophy and decreased vasculature as the disease advances. OBJECTIVE: To assess the changes in epidermal thickness and mucosal vasculature in various stages of the disease. MATERIAL AND METHODS: Patients with histological diagnosis of OSF were included in the study. Demographic data and oral habits of each patient were collected. The severity of OSF was graded histologically according to Pindborg and Sirsat. Epithelial thickness and subepithelial blood vessel area, diameter and perimeter were measured and analysed using Image analysis software IMAGE PRO PLUS version 6.0. RESULTS: Thirty-five patients with OSF were studied. 25 (71.4%) were males and 10 (28.6%) were females with a male to female ratio of 1.3:1. Most patients were in the 31-40 yrs age group. The majority of patients (40%) chewed areca nut/dohra. Each grade of the disease was found to display either hyperplastic or atrophic epithelial changes. The mean blood vessel area, diameter and perimeter did not show any sustained change with the increasing severity (grade) of the disease. CONCLUSION: These findings question the role of ischaemia in the aetiopathogenesis of oral submucous fibrosis.

Role of inflammatory gene polymorphisms in left ventricular dysfunction (LVD) susceptibility in coronary artery disease (CAD) patients.

RATIONALE: Inflammation exacerbates a number of deleterious effects on the heart, most notable being left ventricular dysfunction (LVD). A promoter polymorphism of the NFKB1 gene (encodes p50 subunit) results in lower protein levels of NFkB p50 subunits, which in its dimmer (p50) form has anti-inflammatory effects. The active NFkB transcription factor promotes the expression of over 150 target genes including IL6 and TNF-α. Therefore, the aim of the present study was to assess the association of NFKB1, IL6 and TNF-α gene polymorphisms with LVD in coronary artery disease (CAD) patients. METHODS AND RESULTS: The present study included a total of 830 subjects (600 CAD patients and 230 controls) and was carried out in two (primary and replication) cohorts. CAD patients with reduced left ventricle ejection fraction (LVEF ≤45%) were categorized having LVD. The NFKB1 -94 ATTG ins/del (rs28362491), IL6 -174 G/C (rs1800795) and TNF-α -308 G/A (rs1800629) polymorphisms were genotyped by PCR/ARMS-PCR methods. The results of the primary cohort were validated in a replicative cohort and pooled by meta-analysis using Fisher's and Mantel-Haenszel test. The analysis showed that NFKB1 ATTG/ATTG genotype was significantly associated with LVD (Fisher's method p-value=0.007, Mantel-Haenszel OR=2.34), LV end diastole (p-value=0.013), end systole (p-value=0.011) dimensions, LV mass (p-value=0.024), mean LVEF (p-value=0.001) and myocardial infarction (p-value=0.043). CONCLUSION: Our data suggests that NFKB1 -94 ATTG ins/del polymorphism plays significant role in conferring susceptibility of LVD and ATTG/ATTG genotype may modulate risk of heart failure by increasing ventricular remodeling and worsening LV function.

Gross tracheal deviation: airway challenges and concerns--two case reports.

Practical guidelines and algorithms may not always help in difficult airway management. Large thyroid swellings may be responsible for several difficulties during the perioperative period, such as distortion of the airway, endocrine disturbances and metabolic effects. We here discuss the airway management of two patients with huge thyroid enlargement and gross tracheal deviation. One of those patients had also retrosternal extension of goiter. Both patients were scheduled for an excision of their colloid goiter.

Partial congenital arrhinia: never seen before adult presentation.

BACKGROUND: Arrhinia is defined as the partial or complete absence of the nasal structures. It is a defect of embryonal origin and can be seen in association with other craniofacial anomalies, central nervous system anomalies, absence of paranasal sinuses, and other palatal and ocular abnormalities. Very few patients with arrhinia have been reported so far in the history of modern medicine. CASE REPORT: This study reports an adult patient with congenital partial arrhinia and reviews the literature along with the embryological basis of such a rare disease. CONCLUSION: Arrhinia is a medical condition with scarce documentation in the literature. This article presents the clinical as well as radiological features of this rare entity.

Prospective randomized clinical trial comparing lightweight mesh and heavyweight polypropylene mesh in endoscopic totally extraperitoneal groin hernia repair.

BACKGROUND: The purported advantage of lightweight large-pore meshes is improved biocompatibility that translates into lesser postoperative pain and earlier rehabilitation. However, there are concerns of increased hernia recurrence rate. We undertook a prospective randomized clinical trial to compare early and late outcome measures with the use of a lightweight (Ultrapro) mesh and heavyweight (Prolene) mesh in endoscopic totally extraperitoneal (TEP) groin hernia repair. METHODS: A prospective study was performed on 402 patients (191 in Ultrapro and 211 in Prolene group) with bilateral groin hernias who underwent endoscopic TEP groin hernia repair from March 2006 to June 2007. All operations were performed by five consultants following a standardized operative protocol. Chronic groin pain and hernia recurrence were evaluated as primary outcome measures. Secondary outcome measure were early postoperative pain, operative time, number of fixation devices required to fix the mesh, return to normal daily activities of work, seroma, and testicular pain. RESULTS: At 1-year follow-up, incidence in Ultrapro versus Prolene group for chronic groin pain was 1.6% vs. 4.7% (p = 0.178) and recurrence was 1.3% vs. 0.2% (p = 0.078). In Ultrapro versus Prolene group, mean visual analogue score for postoperative pain at day 7 was 1.07 vs. 1.31 (p = 0.00), mean return to normal activities was 1.82 vs. 2.09 days (p = 0.00), and mean number of fixation devices per patient required to fix the mesh was 4.22 vs. 4.08 (p = 0.043). CONCLUSION: Lightweight meshes appear to have advantages in terms of lesser pain and early return to normal activity. However, more patients had hernia recurrence with lightweight meshes, especially for larger hernias. We surmise that the lightweight meshes have greater tendency to get displaced from their intended position during desufflation at the conclusion of endoscopic TEP repair.

Association between multiple respiratory viral infections and pediatric intensive care unit admission among infants with bronchiolitis.

BACKGROUND: It is unclear whether multiple respiratory viral infections are associated with more severe bronchiolitis requiring pediatric intensive care unit (PICU) admission. We aimed to identify the association between multiple respiratory viral infections and PICU admission among infants with bronchiolitis. METHODS: We performed a 1:1 case-control study enrolling previously healthy full-term infants (≤12 months) with bronchiolitis admitted to the PICU as cases and those to the general pediatric ward as controls from 2015 to 2017. Multiplex polymerase chain reaction (PCR) was used for detection of the respiratory viruses. We summarized the characteristics of infants admitted to the PICU and the general pediatric unit. Multivariable logistic regression analysis was used to fit the association between multiple respiratory viral infections (≥2 strains) and PICU admission. RESULTS: A total of 135 infants admitted to the PICU were compared with 135 randomly selected control infants admitted to the general pediatric unit. The PICU patients were younger (median: 2.2 months, interquartile range: 1.3-4.2) than the general ward patients (median: 3.2 months, interquartile range: 1.6-6.4). Respiratory syncytial virus (74.1%), rhinovirus (28.9%), and coronavirus (5.9%) were the most common viruses for bronchiolitis requiring PICU admission. Patients with bronchiolitis admitted to the PICU tended to have multiple viral infections compared with patients on the general ward (23.0% vs. 10.4%, P<0.001). In the multivariable logistic regression analysis, bronchiolitis with multiple viral infections was associated with higher odds of PICU admission (adjusted odds ratio: 2.56, 95% confidence interval: 1.17-5.57, P=0.02). CONCLUSION: Infants with multiviral bronchiolitis have higher odds of PICU admission compared with those with a single or nondetectable viral infection.

Seeded droplet microfluidic system for small molecule crystallization.

A microfluidic approach to seeded crystallization has been demonstrated using abacavir hemisulfate, a nucleoside analog reverse transcriptase inhibitor, in droplet reactors to control polymorphism and produce particles with a low particle size distribution. Two techniques are introduced: (1) the first technique involves an emulsion system consisting of a dispersed phase solvent and a continuous phase, which holds slight solubility of the dispersed phase solvent. The dispersed phase contains both a dissolved active pharmaceutical ingredient (API) and seeds of the desired polymorph. While the continuous phase enables solvent extraction, the negligible solubility of the API allows for growth of seeds inside droplets via extraction and subsequent API saturation. This technique demonstrates the ability to crystallize the API in spherical agglomerates via slow extraction of droplets. (2) The second technique utilizes a combined dispersed phase by joining in-flow a seed suspension stream with a supersaturated active pharmaceutical ingredient (API) stream. The combined dispersed phase is emulsified in a continuous phase for which the dispersed phase solvent and the API are both insoluble - droplets are incubated at temperatures below their saturation limit to induce crystal growth. Decreasing the concentration of seeds in its input stream resulted in a decreased number of crystals per droplet, increase in crystal size, and decrease in PSD. Temperature cycling was utilized as a proof of concept to demonstrate the ability to reduce the number of seeds per droplet where the optimal goal is to obtain a single seed per droplet for all droplets. Utilizing this approach in conjunction with the ability to produce monodispersed droplet reactors allows for enhanced control of particle size distribution (PSD) by precisely controlling the available mass for each individual seed crystal. The development of this technique as a proof-of-concept for crystallization can be expanded to manufacturing scales in a continuous manner using parallelized droplet generators and flow reactors to precisely control the temperature and crystal growth kinetics of individual droplets.

Laccase of Cyathus bulleri: structural, catalytic characterization and expression in Escherichia coli.

Cyathus bulleri, a ligninolytic fungus, produces a single laccase the internal peptides (3) of which bear similarity to laccases of several white rot fungi. Comparison of the total amino acid composition of this laccase with several fungal laccases indicated dissimilarity in the proportion of some basic and hydrophobic amino acids. Analysis of the circular dichroism spectrum of the protein indicated 37% alpha-helical, 26% beta-sheet and 38% random coil content which differed significantly from that in the solved structures of other laccases, which contain higher beta-sheet structures. The critical role of the carboxylic group containing amino acids was demonstrated by determining the kinetic parameters at different pH and this was confirmed by the observation that a critical Asp is strongly conserved in both Ascomycete and Basidiomycete laccases. The enzyme was denatured in the presence of a number of denaturing agents and refolded back to functional state with copper. In the folding experiments under alkaline conditions, zinc could replace copper in restoring 100% of laccase activity indicating the non-essential role of copper in this laccase. The laccase was expressed in Escherichia coli by a modification of the ligation-anchored PCR approach making it the first fungal laccase to be expressed in a bacterial host. The laccase sequence was confirmed by way of analysis of a 435 bp sequence of the insert.

Long-term symptomatic outcomes after Collis gastroplasty with fundoplication.

Collis gastroplasty with fundoplication is an accepted treatment for gastroesophageal reflux disease (GERD) complicated by short esophagus. The procedure can be done either via left thoracotomy or using minimally invasive laparoscopic techniques. Few centers have reported long-term follow-up for patients undergoing a Collis gastroplasty using both the open and minimal access techniques. Retrospective review of prospectively collected data at Creighton University was done to identify patients who underwent Collis gastroplasty with fundoplication for GERD. After approval from the institutional review board, the patients were contacted and administered a questionnaire regarding symptoms and satisfaction. Data were entered in a dataset and analyzed from the patient's perspective. Eighty-five patients underwent a Collis gastroplasty procedure over a period of 13 years. Forty-eight percent (41 cases) were performed laparoscopically, and a transthoracic open repair was performed in the rest. Long-term data (more than 9 months) was available on 52 patients. Surgery resulted in complete resolution of heartburn, chest pain, regurgitation, and dysphagia in 52, 22, 54, and 29% of patients, respectively. More than 75% of the patients were satisfied with the outcome of surgery, and more than 85% would recommend the procedure to another patient. Collis gastroplasty with fundoplication results in good long-term patient satisfaction and symptom control.

CT Texture Analysis of Cervical Lymph Nodes on Contrast-Enhanced [18F] FDG-PET/CT Images to Differentiate Nodal Metastases from Reactive Lymphadenopathy in HIV-Positive Patients with Head and Neck Squamous Cell Carcinoma.

BACKGROUND AND PURPOSE: Differentiating nodal metastases from reactive adenopathy in HIV-infected patients with [18F] FDG-PET/CT can be challenging because lymph nodes in HIV-positive patients often show increased [18F] FDG uptake. The purpose of this study was to assess CT textural analysis characteristics of HIV-positive and HIV-negative lymph nodes on [18F] FDG-PET/CT to differentiate nodal metastases from disease-specific nodal reactivity. MATERIALS AND METHODS: Nine HIV-positive patients with head and neck squamous cell carcinoma (7 men, 2 women; 29-62 years of age; median age, 48 years) with 22 lymph nodes (≥1 cm) who underwent contrast-enhanced CT with [18F] FDG-PET followed by pathologic evaluation of cervical lymph nodes were retrospectively reviewed. Twenty-six HIV-negative patients with head and neck squamous cell carcinoma with 61 lymph nodes were evaluated as a control group. Each lymph node was manually segmented, and an in-house-developed Matlab-based texture analysis program extracted 41 texture features from each segmented volume. A mixed linear regression model was used to compare the pathologically proved malignant lymph nodes with benign nodes in the 2 enrolled groups. RESULTS: Thirteen (59%) lymph nodes in the HIV-positive group and 22 (36%) lymph nodes in the HIV-negative control group were confirmed as positive for metastases. There were 7 histogram features (P = .017-0.032), 3 gray-level co-occurrence features (P = .009-.025), and 9 gray-level run-length features (P < .001-.033) that demonstrated a significant difference in HIV-positive patients with either benign or malignant lymph nodes. CONCLUSIONS: CT texture analysis may be useful as a noninvasive method of obtaining additional quantitative information to differentiate nodal metastases from disease-specific nodal reactivity in HIV-positive patients with head and neck squamous cell carcinoma.