Mycorrhization in trees: ecology, physiology, emerging technologies and beyond

Mycorrhization has been an integral part of plants since colonization by the early land plants. Over decades, substantial research has highlighted its potential role in improving nutritional efficiency and growth, development and survival of crop plants. However, the focus of this review is trees. Evidence have been provided to explain ecological and physiological significance of mycorrhization in trees. Advances in recent technologies (e.g., metagenomics, artificial intelligence, machine learning, agricultural drones) may open new windows to apply this knowledge in promoting tree growth in forest ecosystems. Dual mycorrhization relationships in trees and even triple relationships among trees, mycorrhizal fungi and bacteria offer an interesting physiological system to understand how plants interact with other organisms for better survival. Besides, studies indicate additional roles of mycorrhization in learning, memorizing and communication between host trees through a common mycorrhizal network (CMN). Recent observations in trees suggest that mycorrhization may even promote tolerance to multiple abiotic (e.g., drought, salt, heavy metal stress) and biotic (e.g. fungi) stresses. Due to the extent of physiological reliance, local adaptation of trees is heavily impacted by the mycorrhizal community. This knowledge opens the possibility of a non-GMO avenue to promote tree growth and development. Indeed, mycorrhization could impact growth of trees in nurserys and subsequent survival of the inoculated trees in field conditions. Future studies might integrate hyperspectral imaging and drone technologies to identify tree communities that are deficient in nitrogen and spray mycorrhizal spore formulations on them.

A Novel Report of mycetoma with Spinal Spread due to Madurella fahalli from India

Eumycetoma caused by Madurella fahalii, a drug-resistant fungus, has never been reported in India. Here, we describe a fatal case of eumycetoma with spinal involvement due to M. fahalii for the first time in India.

Pan-Indian Clinical Registry of Invasive Fungal Infections Among Patients in the Intensive Care Unit: Protocol for a Multicentric Prospective Study

BACKGROUND

Fungal infections are now a great public health threat, especially in those with underlying risk factors such as neutropenia, diabetes, high-dose steroid treatment, cancer chemotherapy, prolonged intensive care unit stay, and so on, which can lead to mycoses with higher mortality rates. The rates of these infections have been steadily increasing over the past 2 decades due to the increasing population of patients who are immunocompromised. However, the data regarding the exact burden of such infection are still not available from India. Therefore, this registry was initiated to collate systematic data on invasive fungal infections (IFIs) across the country.

OBJECTIVE

The primary aim of this study is to create a multicenter digital clinical registry and monitor trends of IFIs and emerging fungal diseases, as well as early signals of any potential fungal outbreak in any region. The registry will also capture information on the antifungal resistance patterns and the contribution of fungal infections on overall morbidity and inpatient mortality across various conditions.

METHODS

This multicenter, prospective, noninterventional observational study will be conducted by the Indian Council of Medical Research through a web-based data collection method from 8 Advanced Mycology Diagnostic and Research Centers across the country. Data on age, gender, clinical signs and symptoms, date of admission, date of discharge or death, diagnostic tests performed, identified pathogen details, antifungal susceptibility testing, outcome, and so on will be obtained from hospital records. Descriptive and multivariate statistical methods will be applied to investigate clinical manifestations, risk variables, and treatment outcomes.

RESULTS

These Advanced Mycology Diagnostic and Research Centers are expected to find the hidden cases of fungal infections in the intensive care unit setting. The study will facilitate the enhancement of the precision of fungal infection diagnosis and prompt treatment modalities in response to antifungal drug sensitivity tests. This registry will improve our understanding of IFIs, support evidence-based clinical decision-making ability, and encourage public health policies and actions.

CONCLUSIONS

Fungal diseases are a neglected public health problem. Fewer diagnostic facilities, scanty published data, and increased vulnerable patient groups make the situation worse. This is the first systematic clinical registry of IFIs in India. Data generated from this registry will increase our understanding related to the diagnosis, treatment, and prevention of fungal diseases in India by addressing pertinent gaps in mycology. This initiative will ensure a visible impact on public health in the country.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/54672.

An integrated FoodNet in North East India: fostering one health approach to fortify public health

BACKGROUND

Food safety is a critical factor in promoting public health and nutrition, especially in developing countries like India, which experience several foodborne disease outbreaks, often with multidrug-resistant pathogens. Therefore, implementing regular surveillance of enteric pathogens in the human-animal-environment interface is necessary to reduce the disease burden in the country.

OBJECTIVE

To establish a network of laboratories for the identification of major food and waterborne pathogens prevailing in the northeast region of India through integrated surveillance of animal, food, human, and environment and investigate the antimicrobial susceptibility pattern of the pathogens of public health significance.

METHODS

The Indian Council of Medical Research (ICMR) has identified FoodNet laboratories; based on their geographical location, inclination to undertake the study, preparedness, proficiency, and adherence to quality assurance procedures, through an 8-step process to systematically expand to cover the Northeastern Region (NER) with comprehensive diagnostic capacities for foodborne pathogens and diarrhea outbreak investigations. Network initiated in the NER given the unique food habits of the ethnic population.

FINDINGS

This surveillance network for foodborne enteric pathogens was established in Assam, Arunachal Pradesh, Tripura, and Sikkim, and expanded to other four states, i.e., Manipur, Mizoram, Meghalaya, and Nagaland, thereby covering the entire NER by including nine medical and three veterinary centers. All these centers are strengthened with periodic training, technical support, funding, capacity building, quality assurance, monitoring, centralized digital data management, and website development.

RESULTS

The ICMR-FoodNet will generate NER-specific data with close to real-time reporting of foodborne disease and outbreaks, and facilitate the updating of food safety management protocols, policy reforms, and public health outbreak response. During 2020-2023, 13,981 food samples were tested and the detection of enteric pathogens ranged from 3 to 4%. In clinical samples, the detection rate of the pathogens was high in the diarrheal stools (8.9%) when 3,107 samples were tested. Thirteen outbreaks were investigated during the study period.

CONCLUSION

Foodborne diseases and outbreaks are a neglected subject. Given the frequent outbreaks leading to the deaths of children, it is crucial to generate robust data through well-established surveillance networks so that a strong food safety policy can be developed for better public health.

Health equity and gendered border blindness: an exploration of healthcare services at the international border in Rajasthan

OBJECTIVES

Citizens' access to health care and the delivery of the healthcare services is significantly affected by the spatiality of the regions and the connectedness of the elements of the healthcare system. This network of healthcare system, region and delivery of services faces myriad challenges in the borderland geography, which is characterised by accentuated military presence, poor physical infrastructure, disinterest of habitation near the border, lack of adequate, necessary and allied services such as schools and industry, social seclusion, migration etc. All these factors amalgamate to create an effect of gender-blind phenomenon as well as border-blind phenomenon. This is particularly acute for women and children.

STUDY DESIGN

A phenomenology research design has been used for the study. It encapsulates qualitative aspects of the views of those who experience marginalisation inclusive of gender-blind experiences. Marginalised women and frontline healthcare workers at the borderland were considered for the inquiry in this study. The study is a composite description of the phenomenon.

METHODS

The border districts of Rajasthan from the Radcliffe line of Rajasthan have been identified for the purpose of the study. Using narrative ethnography along with interviews, an examination was executed from health professionals and marginalised women to comprehend health care access and equity from the service provider's perspective as well as the beneficiary's perspective.

RESULTS

The study provides a range of attributions based on which it could be established that health inequities exist in bordering rural areas.

CONCLUSIONS

The study realises the geopolitical influence of the Radcliffe line, where borderlands are commonly vital to the continuum struggle between the centre and state. Yet, there remains a gap towards implementing various schemes and services due to varied reasons for access from main to far-off border areas, making the situation vulnerable from a resource deficiency point of view. The Health Equity Framework cannot meet Social Determinants of Health in borderland areas of Rajasthan.

The Development of a Clinical Registry Digital Database on Invasive Fungal Infections in India: Advancing Epidemiological Understanding and Patient Care

A well-structured digital database is essential for any national priority project as it can provide real-time data analysis and facilitate quick decision making. In recent times, particularly after the COVID-19 pandemic, invasive fungal infections (IFIs) have emerged as a significant public health challenge in India, affecting vulnerable population, including immunocompromised individuals. The lack of comprehensive and well-structured data on IFIs has hindered efforts to understand their true burden and optimize patient care. To address this critical knowledge gap, the ICMR has undertaken a Pan-India pioneer initiative to develop a network of Advanced Mycology Diagnostic research centres in different geographical zones of the country (ICMR-MycoNet). Under the aegis of this project, a clinical registry on IFIs in the ICUs is initiated. This process paper presents a detailed account of the steps involved in the establishment of a web-based data entering and monitoring platform to capture data electronically, ensuring robust and secure data collection and management. This system not only allows participating ICMR-MycoNet centres to enter patient information directly into the database using standardized Case Report Form (CRF) but also includes data validation checks to ensure the accuracy and completeness of entered data. It is complemented by a real-time, web-based, and adaptable data visualization platform. This registry aims to provide crucial epidemiological insights, promote evidence-based hospital infection control programs, and ultimately improve patient outcomes in the face of this formidable healthcare challenge.

CNS Control after First-Line Osimertinib in Patients with Metastatic EGFR-Mutant NSCLC

PURPOSE/OBJECTIVE(S)

Although osimertinib (osi) has excellent intracranial activity in EGFR-mutant metastatic non-small cell lung cancer (NSCLC), there is no consensus regarding whether to continue osi for central nervous system (CNS) control with second-line chemotherapy (chemo) at the time of systemic progression. We aimed to compare CNS outcomes after first-line osi in patients receiving second-line chemo with or without continuation of osi.

MATERIALS/METHODS

We retrospectively reviewed patients with EGFR-mutant NSCLC with brain metastases (BrM) at the time of initiating first-line osi who experienced progression and started second-line chemo. Cumulative incidence of local and distant CNS progression, and extracranial (EC) progression was calculated from time of second-line chemo initiation with death as a competing risk. Overall survival (OS) was analyzed using Kaplan-Meier.

RESULTS

We included 52 patients with a median follow up of 9.6 months (range 0.4-36.4). Median OS and CNS progression-free survival (PFS) from the time of starting second-line chemo was 12.5 months (95% CI 8.1-16.9), and 5.3 months (95% CI 3.35-7.26), respectively. The 1-year cumulative incidence of local, distant CNS progression, any CNS progression, and EC progression was 14.4% (95% CI 4.5-24.2), 42.8% (95% CI 22.8-56.8), 42.8% (95% CI 22.8-56.8) and 66.8% (95% CI 53.5-80.2), respectively. After progression on first-line osi, 25 (48.1%) and 27 patients (51.9%) continued and discontinued osi, respectively. Patients who continued osi had significantly higher BrM burden than those who did not, with 17 (68%), 3 (12%), and 5 (20%) versus 26 (96%), 0, and 1 (3.7%) patient having <10 or >11 parenchymal brain lesions, or leptomeningeal disease (LMD) at the time of second line therapy, respectively (p<0.01). In those who continued osi vs those who did not, median OS (10.8 vs 12.5 months; p = 0.37), median intracranial PFS (5.3 vs 4.8 months; p = 0.99), 1-year cumulative incidence of local (8.4% versus 20 % p = 0.26), and 1-year distant CNS progression (24.8% vs 60%; p = 0.08) was not significantly different. CNS complications such as symptomatic, hospitalizations, and steroid initiation for CNS disease, and progression of LMD were not significantly different between the two groups. Eventually, 10 patients underwent salvage RT post first-line osi and median time to salvage RT was 7.8 months (range 2-9.4). Of patients who underwent salvage RT, 2 patients (20%) had continued osi with second-line chemo. Twelve patients (44.4%) who did not continue osi eventually re-started osi for progressive disease.

CONCLUSION

Patients who continued osi had significantly higher BrM tumor burden. Despite these patients being at higher risk for CNS progression, time to CNS progression and incidence of CNS complications were not significantly different in the two cohorts. Patients who discontinued osi were more likely to undergo salvage RT. Continuation of osi may allow patients to defer salvage RT.

Satellite Epidemic of Covid-19 Associated Mucormycosis in India: A Multi-Site Observational Study

BACKGROUND

Sudden upsurge in cases of COVID-19 Associated Mucormycosis (CAM) following the second wave of the COVID-19 pandemic was recorded in India. This study describes the clinical characteristics, management and outcomes of CAM cases, and factors associated with mortality.

METHODS

Microbiologically confirmed CAM cases were enrolled from April 2021 to September 2021 from ten diverse geographical locations in India. Data were collected using a structured questionnaire and entered into a web portal designed specifically for this investigation. Bivariate analyses and logistic regression were conducted using R version 4.0.2.

RESULTS

A total of 336 CAM patients were enrolled; the majority were male (n = 232, 69.1%), literate (n = 261, 77.7%), and employed (n = 224, 66.7%). The commonest presenting symptoms in our cohort of patients were oro-facial and ophthalmological in nature. The median (Interquartile Range; IQR) interval between COVID diagnosis and admission due to mucormycosis was 31 (18, 47) days, whereas the median duration of symptoms of CAM before hospitalization was 10 (5, 20) days. All CAM cases received antifungal treatment, and debridement (either surgical or endoscopic or both) was carried out in the majority of them (326, 97.02%). Twenty-three (6.9%) of the enrolled CAM cases expired. The odds of death in CAM patients increased with an increase in HbA1c level (aOR: 1.34, 95%CI: 1.05, 1.72) following adjustment for age, gender, education and employment status.

CONCLUSION

A longer vigil of around 4-6 weeks post-COVID-19 diagnosis is suggested for earlier diagnosis of CAM. Better glycemic control may avert mortality in admitted CAM cases.

Operationalising targeted next-generation sequencing for routine diagnosis of drug-resistant TB

BACKGROUND

Phenotypic drug susceptibility testing (pDST) for Mycobacterium tuberculosis can take up to 8 weeks, while conventional molecular tests identify a limited set of resistance mutations. Targeted next-generation sequencing (tNGS) offers rapid results for predicting comprehensive drug resistance, and this study sought to explore its operational feasibility within a public health laboratory in Mumbai, India.

METHODS

Pulmonary samples from consenting patients testing Xpert MTB-positive were tested for drug resistance by conventional methods and using tNGS. Laboratory operational and logistical implementation experiences from study team members are shared below.

RESULTS

Of the total number of patients tested, 70% (113/161) had no history of previous TB or treatment; however, 88.2% (n = 142) had rifampicin-resistant/multidrug-resistant TB (RR/MDR-TB). There was a high concordance between resistance predictions of tNGS and pDST for most drugs, with tNGS more accurately identifying resistance overall. tNGS was integrated and adapted into the laboratory workflow; however, batching samples caused significantly longer result turnaround time, fastest at 24 days. Manual DNA extraction caused inefficiencies; thus protocol optimisations were performed. Technical expertise was required for analysis of uncharacterised mutations and interpretation of report templates. tNGS cost per sample was US$230, while for pDST this was US$119.

CONCLUSIONS

Implementation of tNGS is feasible in reference laboratories. It can rapidly identify drug resistance and should be considered as a potential alternative to pDST.

Higher proinflammatory responses possibly contributing to suppressed cytotoxicity in patients with COVID-19 associated mucormycosis

INTRODUCTION

COVID-19 Associated Mucormycosis (CAM), an opportunistic fungal infection, surged during the second wave of SARS Cov-2 pandemic. Since immune responses play an important role in controlling this infection in immunocompetent hosts, it is required to understand immune perturbations associated with this condition for devising immunotherapeutic strategies for its control. We conducted a study to determine different immune parameters altered in CAM cases as compared to COVID-19 patients without CAM.

METHODOLOGY

Cytokine levels in serum samples of CAM cases (n = 29) and COVID-19 patients without CAM (n = 20) were determined using luminex assay. Flow cytometric assays were carried out in 20 CAM cases and 10 controls for determination of frequency of NK cells, DCs, phagocytes, T cells and their functionalities. The cytokine levels were analyzed for their association with each other as well as with T cell functionality. The immune parameters were also analyzed with respect to the known risk factors such as diabetes mellitus and steroid treatment.

RESULTS

Significant reduction in frequencies of total and CD56 + CD16 + NK cells (cytotoxic subset) was noted in CAM cases. Degranulation responses indicative of cytotoxicity of T cell were significantly hampered in CAM cases as compared to the controls. Conversely, phagocytic functions showed no difference in CAM cases versus their controls except for migratory potential which was found to be enhanced in CAM cases. Levels of proinflammatory cytokines such as IFN-γ, IL-2, TNF-α, IL-17, IL-1β, IL-18 and MCP-1 were significantly elevated in cases as compared to the control with IFN-γ and IL-18 levels correlating negatively with CD4 T cell cytotoxicity. Steroid administration was associated with higher frequency of CD56 + CD16- NK cells (cytokine producing subset) and higher MCP-1 levels. Whereas diabetic participants had higher phagocytic and chemotactic potential and had higher levels of IL-6, IL-17 and MCP-1.

CONCLUSION

CAM cases differed from the controls in terms of higher titers of proinflammatory cytokines, reduced frequency of total and cytotoxic CD56 + CD16 + NK cell. They also had reduced T cell cytotoxicity correlating inversely with IFN-γ and IL-18 levels, possibly indicating induction of negative feedback mechanisms while diabetes mellitus or steroid administration did not affect the responses negatively.

Clinical utility of target-based next-generation sequencing for drug-resistant TB

BACKGROUND: In high TB burden countries, access to drug susceptibility testing is a major bottleneck. Targeted next-generation sequencing (tNGS) is a promising technology for rapid resistance detection. This study assessed the role of tNGS for the diagnosis of drug-resistant TB (DR-TB).METHODS: A total of 161 samples from bacteriologically confirmed TB cases were subjected to tNGS using the Deeplex^® Myc-TB kit and sequenced using the MiSeq platform. These samples were also processed for conventional phenotypic DST (pDST) using 13 drugs on Mycobacteria Growth Indicator Tube and line-probe assays (MTBDRplus and MTBDRsl).RESULTS: There were 146 DR-TB and 15 drug-susceptible TB (DS-TB) samples. About 70% of patients with DR-TB had no previous TB treatment history. Overall, 88.2% had rifampicin-resistant/multidrug-resistant TB (RR/MDR-TB), 58.5% pre-extensively drug-resistant TB (pre-XDR-TB) and 9.2% had XDR-TB as defined by the WHO (2020). Around 8% (n = 13) of samples were non-culturable; however, identified 8 were resistant to first and second-line drugs using tNGS. Resistance frequency was similar across methods, with discordance in drugs less reliable using pDST or with limited mutational representation within databases. Sensitivities were aligned with literature reports for most drugs. We observed 10% heteroresistance, while 75% of strains were of Lineages 2 and 3.CONCLUSIONS: Programme data supported tNGS in the diagnosis of DR-TB for early treatment using individualised regimens.

A case control investigation of COVID-19 associated mucormycosis in India

Background

Increased occurrence of mucormycosis during the second wave of COVID-19 pandemic in early 2021 in India prompted us to undertake a multi-site case–control investigation. The objectives were to examine the monthly trend of COVID-19 Associated Mucormycosis (CAM) cases among in-patients and to identify factors associated with development of CAM.

Methods

Eleven study sites were involved across India; archived records since 1st January 2021 till 30th September 2021 were used for trend analysis. The cases and controls were enrolled during 15th June 2021 to 30th September 2021. Data were collected using a semi-structured questionnaire. Among 1211 enrolled participants, 336 were CAM cases and 875 were COVID-19 positive non-mucormycosis controls.

Results

CAM-case admissions reached their peak in May 2021 like a satellite epidemic after a month of in-patient admission peak recorded due to COVID-19. The odds of developing CAM increased with the history of working in a dusty environment (adjusted odds ratio; aOR 3.24, 95% CI 1.34, 7.82), diabetes mellitus (aOR: 31.83, 95% CI 13.96, 72.63), longer duration of hospital stay (aOR: 1.06, 95% CI 1.02, 1.11) and use of methylprednisolone (aOR: 2.71, 95% CI 1.37, 5.37) following adjustment for age, gender, occupation, education, type of houses used for living, requirement of ventilatory support and route of steroid administration. Higher proportion of CAM cases required supplemental oxygen compared to the controls; use of non-rebreather mask (NRBM) was associated as a protective factor against mucormycosis compared to face masks (aOR: 0.18, 95% CI 0.08, 0.41). Genomic sequencing of archived respiratory samples revealed similar occurrences of Delta and Delta derivates of SARS-CoV-2 infection in both cases and controls.

Conclusions

Appropriate management of hyperglycemia, judicious use of steroids and use of NRBM during oxygen supplementation among COVID-19 patients have the potential to reduce the risk of occurrence of mucormycosis. Avoiding exposure to dusty environment would add to such prevention efforts.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-022-07844-y.

UK multi-centre retrospective study of the learning curve and relative performance of the rhythmia high density mapping system for atrial ablation

Funding Acknowledgements

Type of funding sources: Public hospital(s). Main funding source(s): University Hospital Southampton

Background

Rhythmia HDx® is a novel ultra-high density electroanatomical mapping system using an innovative 64 electrode basket catheter. A learning curve is a recognised phenomenon for any new technology and was examined in this study.

Purpose

Comparison of performance, long-term success, and complications using Rhythmia for atrial ablation in the UK.

Methods

Retrospective data collection from three centres across the UK from the introduction of Rhythmia. Patients were matched with controls who had undergone ablation using the well-established Carto3 mapping system. Assessed were: fluoroscopy, radiofrequency ablation and procedure times; acute and long term success, and complications.

Results

253 study patients with 253 controls were included. Significant correlations existed between procedural efficiency metrics and centre experience for de novo atrial fibrillation (AF) ablation (procedure time, Spearman’s ρ = -0.624; ablation time, ρ = -0.795), and de novo atrial flutter (AFlut) ablation (ablation time, ρ = -0.566; fluoroscopy time, ρ = -0.520). No such correlations existed for redo AF, redo AFlut, de novo atrial tachycardia (AT), or redo AT cases. For de novo AF and AFlut, procedural efficiency metrics were significantly improved after 10 procedures in each centre, (procedure time [AF only, p = 0.001], ablation time [AF, p &lt; 0.0005; AFlut p &lt; 0.0005] and fluoroscopy time [AFlut only, p = 0.0022]), and became comparable to controls (Figures 1 and 2). Acute success and long-term success did not see significant improvement with experience but were comparable to the control group. There was no relationship between experience and complications, which were comparable to Carto3 (3.6% in both groups).

Conclusion

A short learning curve exists with the use of Rhythmia HDx for standardised procedures (de novo AF / AFlut). Procedural performance improves and becomes comparable to Carto3 following 10 cases at each centre. Clinical outcomes at 6 and 12 months, and complications are not affected by this learning curve and remain comparable with controls.

Mycobacterium tuberculosis strain lineage in mixed tribal population across India and Andaman Nicobar Island

In India, the tribal population constitutes almost 8.6% of the nation's total population. Despite their large presence, there are only a few reports available on Mycobacterium tuberculosis (M. tb) strain prevalence in Indian tribal communities considering the mobile nature of this population and also the influence of the mainstream populations they coexist within many areas for their livelihood. This study attempts to provide critical information pertaining to the TB strain diversity, its public health implications, and distribution among the tribal population in eleven Indian states and Andaman & Nicobar (A&N) Island. The study employed a population-based molecular approach. Clinical isolates were received from 66 villages (10 states and Island) and these villages were selected by implying situation analysis. A total of 78 M. tb clinical isolates were received from 10 different states and A&N Island. Among these, 16 different strains were observed by spoligotyping technique. The major M. tb strains spoligotype belong to the Beijing, CAS1_DELHI, and EAI5 family of M. tb strains followed by EAI1_SOM, EAI6_BGD1, LAM3, LAM6, LAM9, T1, T2, U strains. Drug-susceptibility testing (DST) results showed almost 15.4% of clinical isolates found to be resistant to isoniazid (INH) or rifampicin (RMP) + INH. Predominant multidrug-resistant (MDR-TB) isolates seem to be Beijing strain. Beijing, CAS1_DELHI, EAI3_IND, and EAI5 were the principal strains infecting mixed tribal populations across India. Despite the small sample size, this study has demonstrated higher diversity among the TB strains with significant MDR-TB findings. Prevalence of Beijing MDR-TB strains in Central, Southern, Eastern India and A&N Island indicates the transmission of the TB strains.

Eruptive keratoacanthomas associated with dupilumab therapy

We would like to present the case of eruptive keratoacanthomas associated with dupilumab therapy, which occurred in an 85-year-old woman receiving biologic therapy for the treatment of atopic dermatitis. With the increasing prevalence of Dupilumab usage, this is an important potential complication of which clinicians should be aware.

Irreversibility Analysis of 3D Magnetohydrodynamic Casson Nanofluid Flow Past Through Two Bi-Directional Stretching Surfaces with Nonlinear Radiation

Application of the nanoparticles with different non-Newtonian base fluid has huge application in the industries where the heat generation or energy transform takes place and many such applications are designing the advanced energy system at high temperature, aerodynamics, energy extraction etc. In the present study, we have analyzed irreversibility for a 3-dimensional MHD, incompressible, electrically conducting Casson nanofluid flow through the two horizontal stretching surfaces. To make it more practical and broad, the flow field has been incorporated with porosity, suction/injection, non-linear radiation with fall velocity with convective heating conditions at the boundaries and entropy generation which is an important physical phenomenon in thermodynamics. Influence of imperative parameters of the flow field and physical parameters have discussed with the entropy generation. In a limiting case, a comparison made. It is observed that the suction phenomena boost up the local Nusselt and Sherwood number at the surface while restricted the skin friction. The non-Newtonian rheology (as Casson number) restricted the skin friction and the same phenomena observed for the local heat and mass transfer. The entropy boosts up with the enhancement of the magnetic parameter, temperature ratio and Brinkman number. Further nanoparticle concentration improve the thermal conductivity leads an improvement in the efficiency of the heat transfer takes place. With the augment in thermal radiation, magnetic parameter and Brinkman number, the entropy generation of the systems gets accelerated.

Clinical efficacy of grape seed extract as an adjuvant to scaling and root planing in treatment of periodontal pockets

Grape seed extract (GSE), a naturally producing polyphenolic compound, is found to be a potent hostmodulatory agent and considered for management of periodontal disease. Its anti-bacterial, antioxidant, and anti-inflammatory property may aid in achieving periodontal health. To assess the clinical efficacy of GSE in adjunct to scaling and root planing (SRP) in healing of periodontal pockets. The present study was a longitudinal, parallel design, randomized clinical trial. Seventy-two patients (mean age 39.2±8.6 years) with periodontal pockets were randomly divided into two groups; Test group received intra-pocket delivery of GSE with SRP and Control group received SRP alone. The clinical parameters like Plaque Index (PI), Gingival Index (GI), Probing Depth (PD) and Relative Attachment Level (RAL) were recorded at baseline and 3 months. 64 patients completed the study. Test group at the end of 3 months had statistically significant reduced PD (p=0.002) and RAL (p=0.01). No significant difference was observed for PI and GI at the end of 3 months. Intra-pocket application of GSE with SRP could be beneficial in management of periodontal pockets.

Prevalence of pulmonary tuberculosis among the tribal populations in India

Importance

There is no concrete evidence on the burden of TB among the tribal populations across India except for few studies mainly conducted in Central India with a pooled estimation of 703/100,000 with a high degree of heterogeneity.

Objective

To estimate the prevalence of TB among the tribal populations in India.

Design, participants, setting

A survey using a multistage cluster sampling design was conducted between April 2015 and March 2020 covering 88 villages (clusters) from districts with over 70% tribal majority populations in 17 States across 6 zones of India. The sample populations included individuals ≥15 years old.

Main outcome and measures

Eligible participants who were screened through an interview for symptoms suggestive of pulmonary TB (PTB); Two sputum specimens were examined by smear and culture. Prevalence was estimated after multiple imputations for non-coverage and a correction factor of 1.31 was then applied to account for non-inclusion of X-ray screening.

Results

A total of 74532 (81.0%) of the 92038 eligible individuals were screened; 2675 (3.6%) were found to have TB symptoms or h/o ATT. The overall prevalence of PTB was 432 per 100,000 populations. The PTB prevalence per 100,000 populations was highest 625 [95% CI: 496–754] in the central zone and least 153 [95% CI: 24–281] in the west zone. Among the 17 states that were covered in this study, Odisha recorded the highest prevalence of 803 [95% CI: 504–1101] and Jammu and Kashmir the lowest 127 [95% CI: 0–310] per 100,000 populations. Findings from multiple logistic regression analysis reflected that those aged 35 years and above, with BMI <18.5 Kgs /m², h/o ATT, smoking, and/or consuming alcohol had a higher risk of bacteriologically positive PTB. Weight loss was relatively more important symptom associated with tuberculosis among this tribal populations followed by night sweats, blood in sputum, and fever.

Conclusion and relevance

The overall prevalence of PTB among tribal groups is higher than the general populations with a wide variation of prevalence of PTB among the tribal groups at zone and state levels. These findings call for strengthening of the TB control efforts in tribal areas to reduce TB prevalence through tribal community/site-specific intervention programs.

Understanding health care-seeking behaviour of the tribal population in India among those with presumptive TB symptoms

BACKGROUND AND OBJECTIVES

Understanding the drivers for care-seeking among those who present with symptoms of TB is crucial for early diagnosis of TB and prompt treatment, which will in turn halt further TB transmission. While TB is a challenge among the tribal population, little is known about the care-seeking behaviour and the factors influencing care-seeking behaviour among the tribal population across India.

METHODOLOGY

This community-based descriptive study was carried out in 17 states of India across 6 zones, covering 88 villages from tribal districts with over 70% tribal population. The sample population included individuals ≥15 years old who were screened through an interview for symptoms suggestive of pulmonary TB (PTB), currently and/or previously on anti-TB treatment. Those with symptoms were then assessed on their health-seeking behavior using a semi-structured interview schedule.

RESULTS

Among 74532 eligible participants screened for symptoms suggestive of TB, 2675 (3.6%) were found to be presumptive TB cases. Of them, 659 (24.6%) sought care for their symptoms. While 48.2% sought care after a week, 19.3% sought care after one month or more, with no significant difference in the first point of care; 46.9% approaching a private and 46.7% a public facility. The significant factors influencing care-seeking behaviour were knowledge on TB (OR: 4.64 (3.70-5.83), p < 0.001), age<35 years (OR: 1.60 (1.28-2.00), p < 0.001), co-morbidities like asthma (OR: 1.80 (1.38-2.35), p < 0.001) and blood pressure (OR: 2.59 (1.75-3.85), p < 0.001), symptoms such as blood in sputum (OR: 1.69 (1.32-2.16), p < 0.001), shortness of breath (OR: 1.43 (1.19-1.72), p < 0.001) and weight loss (OR: 1.59 (1.33-1.89), p < 0.001). The cough was the most often reported symptom overall. There were gender differences in symptoms that prompted care-seeking: Males were more likely to seek care for weight loss (OR: 1.78 (1.42-2.23), p<0.001), blood in the sputum (OR: 1.69 (1.25-2.28), p<0.001), shortness of breath (OR: 1.49 (1.18-1.88), p<0.001) and fever (OR: 1.32 (1.05-1.65), p = 0.018). Females were more likely to seek care for blood in sputum (OR: 1.68 (1.10-2.58), p = 0.018) and shortness of breath (OR = 1.35, (1.01-1.82), p = 0.048). The cough did not feature as a significant symptom that prompted care-seeking.

CONCLUSION

Delayed healthcare-seeking behaviour among those with symptoms presumptive of TB in the tribal population is a major concern. Findings point to differences across gender about symptoms that prompt care-seeking in this population. Gender-sensitive interventions with health system strengthening are urgently needed to facilitate early diagnosis and treatment among this population.

New TB drugs for the treatment of children and adolescents with rifampicin-resistant TB in Mumbai, India

SETTING: Médecins Sans Frontières (MSF) clinic in Mumbai, India.OBJECTIVE: To determine the final treatment outcomes, culture conversion and adverse events (AEs) during treatment among children and adolescents (0-19 years) with rifampicin-resistant tuberculosis (RR-TB) who received ambulatory injectable-free treatment, including bedaquiline (BDQ) and/or delamanid (DLM) during September 2014-January 2020.DESIGN: This was a retrospective cohort study based on review of routinely collected programme data.RESULTS: Twenty-four patients were included; the median age was 15.5 years (min-max 3-19) and 15 (63%) were females. None were HIV-coinfected. All had fluoroquinolone resistance. Twelve received treatment, including BDQ and DLM, 11 received DLM and one BDQ. The median exposure to BDQ (n = 13) and DLM (n = 23) was 82 (IQR 80-93) and 82 (IQR 77-96) weeks, respectively. Seventeen (94%) patients with positive culture at baseline (n = 18) had negative culture during treatment; median time for culture-conversion was 7 weeks (IQR 5-11). Twenty-three (96%) had successful treatment outcomes: cured (n = 16) or completed treatment (n = 7); one died. Eleven (46%) had 17 episodes of AEs. Two of 12 serious AEs were associated with new drugs (QTcF >500 ms).CONCLUSION: Based on one of the largest global cohorts of children and adolescents to receive new TB drugs, this study has shown that injectable-free regimens containing BDQ and/or DLM on ambulatory basis were effective and well-tolerated among children and adolescents and should be made routinely accessible to these vulnerable groups.

Nature of sorption of trivalent arsenic on novel iron oxyhydroxide stabilized starch/OMMT composite: A mechanistic approach

Materials which are chemically, energetically and operationally acceptable for arsenic water treatment are highly required. In this study a hybrid material (SICC) of aminated starch, oxyhydroxide of iron and OMMT clay has been demonstrated for arsenic treatment. This new material was highly efficient in arsenic water treatment which could reduce arsenic concentration far below detection limits. All binding interactions during material preparation and arsenic sorption were exclusively characterized with FT-IR, XRD and other spectroscopic tools. A molecular modeling on the basis of density functional theory was carried out to verify the above findings. Influence of material dose, treatment time, initial ion concentration, varying temperatures, etc., on extent of sorption was studied in detail. The thermodynamic parameters viz. ΔG (>-11 kJ/mol), ΔH (42.48 kJ/mol), ΔS (177.6 JK^-1 mol^-1) and E a (59.16 kJ/mol) determined the feasibility of the process, its endothermic behavior and most importantly the chemical nature of the sorption accompanied by ion-exchange to some extent. The sorption followed a monolayer chemisorption pattern as determined by the Langmuir model (R² = 0.973, R L = 0.081) with a q_max = 2.04 at 303 K. The binding of As(III) on the material was governed by a pseudo second order kinetic model.

Understanding demand for, and feasibility of, centre-based child-care for poor urban households: a mixed methods study in Dhaka, Bangladesh

Background

Centre-based child-care has potential to provide multiple health and development benefits to children, families and societies. With rapid urbanisation, increasing numbers of low-income women work with reduced support from extended family, leaving a child-care vacuum in many low- and middle-income countries. We aimed to understand perceptions of, and demand for, centre-based child-care in Dhaka, Bangladesh among poor, urban households, and test the feasibility of delivering sustainable centre-based child-care.

Methods

We used sequential mixed methods including a household survey (n = 222) and qualitative interviews with care-givers (n = 16), community leaders (n = 5) and policy-makers (n = 5). We co-produced and piloted a centre-based child-care model over ten-months, documenting implementation. A co-design focus group with mothers, parents’ meetings, and qualitative interviews with child-care centre users (n = 5), non-users (n = 3), ex-users (n = 3) and staff (2) were used to refine the model and identify implementation issues.

Results

We found 24% (95% CI: 16,37%) of care-givers reported turning-down paid work due to lack of child-care and 84% (95% CI:74, 91%) reported wishing to use centre-based child-care and were willing to pay up to 283 Takka (~$3.30) per month. Adjusted odds of reported need for child-care among slum households were 3.8 times those of non-slum households (95% CI: 1.4, 10). Implementation highlighted that poor households needed free child-care with food provided, presenting feasibility challenges. Meta-inference across quantitative and qualitative findings identified the impact of the urban environment on child-care through long working hours, low social capital and fears for child safety. These influences interacted with religious and social norms resulting in caution in using centre-based child-care despite evident need.

Conclusion

Sustainable provision of centre-based care that focuses on early childhood development requires subsidy and careful design sensitive to the working lives of poor families, particularly women and must respond to the dynamics of the urban environment and community values. We recommend increased research and policy focus on the evaluation and scale-up of quality centre-based child-care, emphasising early-childhood development, to support low-income working families in urban areas.

Gluconeogenic fructose-1,6-bisphosphatase from the mature sporocarps of common aquatic ferns: partial purification and basic characterization of this enzyme from Marsilea minuta (Polypodiopsida)

The present communication reports substantial activity of gluconeogenic fructose-1,6-bisphosphatase (FBPase; EC 3.1.3.11) in three common heterosporous aquatic ferns (Marsilea minuta, Salvinia natans, and Azolla pinnata) and also describes a protocol for its partial purification from mature sporocarps of Marsilea minuta. The cytosolic FBPase, obtained from Marsilea minuta, Salvinia natans, and Azolla pinnata was recognized as gluconeogenic enzyme due to its drastic catabolic inactivation in presence of externally administered glucose and its insensitivity towards photosynthetic light illumination. Cytosolic gluconeogenic FBPase was partially purified from mature sporocarps of Marsilea minuta to about 22-fold over homogenate following low-speed centrifugation (11, 400 × g), 30–80% ammonium sulfate fractionation followed by subsequent chromatography using matrices like CM-Cellulose, Sephadex G-200, and Ultrogel AcA 34. The profile of partially purified FBPase in PAGE under non-denaturing condition was recorded. The enzyme activity increased linearly with respect to protein concentration to about 100 µg and with respect to time up to 75 minutes. Temperature optimum was found at 35 °C. The effect of substrate concentration and kinetic analyses for FBPase were carried out using D-fructose-1,6-bisphosphate (D-FBP, the substrate) in the range of 0.0 to 1.0 mM at an interval of 0.1 mM concentration. The Km value for D-FBP of FBPase was 0.06129 mM and Vmax was 4525 nmole Pi released (mg)-1 protein h-1 as determined by nonlinear regression kinetics using Prism 8 software (Graph Pad). The enzyme was functional in a constricted pH range of 7.0 to 8.0, giving maxima at pH 7.5. This cytosolic enzyme was significantly stimulated by Mg2+ and strongly inhibited by Hg2+, Cu2+ and Zn2+.

A case of solitary kidney with duplex collecting systems and renal vascular variants in an adult male cadaver

We describe a unique solitary kidney with duplex collecting system and vascular variation observed in an 86-year-old white male formaldehyde- and phenol-fixed cadaver during routine academic dissection. The left renal fossa was empty with an intact adrenal gland, and the right renal fossa contained a fused renal mass with apparent polarity between the superior and inferior regions and two renal pelves converging into a single ureter. There were three right renal arteries supplying the renal mass; the superior and middle arteries were noted to be postcaval and the inferior artery was precaval. There were also two right renal veins draining into the inferior vena cava and following a regional distribution with the superior vein draining the inferior portion of the renal mass. Despite generally being asymptomatic, the detection of renal anatomical variants is clinically important for appropriate patient management and surgical interventions.

Antibacterial metabolites from Bipolaris specifera, an endophytic fungus from the endemic medicinal plant, Zingiber nimmonii (J. Graham) Dalzell

Eleven fungal endophytes were isolated from the plant parts of Z. nimmonii (J. Graham) Dalzell, an endemic species of the Western Ghats, India, a biodiversity hotspot area. The endophytic isolates were characterized by the sequencing of the Internal Transcribed Spacer (ITS) regions and designated as strains by depositing ITS sequences in the Gen Bank sequence database. All the strains were cultured in Potato Dextrose broth (PDB, 500 mL) contained in Erlenmeyer flasks to obtain the secondary metabolites. The culture filtrate was extracted with ethyl-acetate (EA) three times and concentrated by flash evaporation to obtain EA crude dry extract. The strains were evaluated for the antibacterial potentials against six pathogenic bacterial strains viz., Bacillus subtilis (MTCC 121), Staphylococcus aureus (MTCC 7443) Pseudomonas aeruginosa (MTCC 7093), Escherichia coli (MTCC 729), Enterobacter aerogenes (MTCC 111) and Klebsiella pneumoniae (MTCC 661). Nine endophytic fungal extracts except Alternaria consortiale and Hypocrea lixi showed inhibitory activities against at least two of the six test bacterial strains. Bipolaris specifera (KM114290) exhibited the highest inhibition zones ranging from 15.1 ± 0.3 to 26.7 ± 1.1 mm (diameter), against all six test bacteria in the agar disk diffusion assay, and with Minimum Inhibitory Concentrations (MIC's) of 0.04-0.14 mg/mL, followed by Aspergillus terreus. B. specifera extract was therefore selected and characterized for the identification of antibacterial compounds by chromatographic techniques. Seven antibacterial compounds viz., (1) Bicyclo[3.2.0]heptan-2-one, 6-hydroxy-5-methyl-6-vinyl; (2) Adipic acid divinyl ester; (3) 1,4-Naphthoquinone, 6-acetyl-2,5-dihydroxy; (4) Decanedioic acid, 3,7-dimethyl ester; (5) (Z)-4-Hexenoic acid 2-acetyl-2-methyl-ethyl ester and (6) Butanoic acid 2-acetyl-3-methyl-methyl ester and (7) Caffeic acid, were identified through liquid and gas chromatography. These compounds are mainly volatile esters of fatty acids, phenolics and adipic acid found rare in nature. This study envisages the possible drug discovery using endophytes from traditional and endemic medicinal species.

The performance of non-ECG gated chest CT for cardiac assessment - The cardiac pathologies in chest CT (CaPaCT) study

PURPOSE

Evaluating the prevalence of CAD on non-ECG gated chest CTs, image quality (IQ) and the clinical performance of the CAD-RADS classification for predicting cardiovascular events (CVE).

METHODS

215 consecutive patients referred for chest CTs between May 2016 and March 2018 were included (3rd-generation DSCT) using non-ECG gated acquisitions with automated tube voltage selection (110kV_qual.ref/40mAs_qual.ref), pitch 2.65-3.0 and individualized contrast media injection protocols. Dedicated cardiac post-processing reconstructions (0.6 mm/0.4 mm/Kernel Bv36) were added to standard chest reconstructions. Two independent cardiac radiologists performed a 3-step analysis. In case of discrepancy, a third reader gave the final decision. Step 1: visual presence of calcifications; 2: scans with calcifications assessed for IQ using a 5-point Likert scale (poor/sufficient/moderate/good/excellent); 3: stenosis severity was analysed in detail (if Likert sufficient-excellent using CAD-RADS). Electronic patient files were checked to see if pathology was previously mentioned (incidental) and whether patients developed an CVE during follow-up.

RESULTS

1: Calcifications were present in 156/215 cases (72.6 %), 74 of these were incidental. 2: In 68/156 (43.6 %) patients with calcifications IQ was rated sufficient-excellent. 3: CAD-RADS≥3 was seen in 39/68 patients (57.4 %), 12 times (30.8 %) findings were incidental. During follow-up (median 16 [0-35] months), 7/39 (18 %) patients with CAD-RADS≥3 developed a CVE. 17 patients died during follow-up.

CONCLUSION

Coronary calcification on non ECG-gated chest CTs was detected in 72.6 % of patients, cardiac assessment was feasible in nearly half of these patients. Only patients with a CAD-RADS≥3 developed CVE, therefore the CAD-RADS may help identify and guide patients at risk of future CVE.

Modeling the effect of area deprivation on COVID-19 incidences: a study of Chennai megacity, India

Objectives

Socio-economic inequalities may affect coronavirus disease 2019 (COVID-19) incidence. The goal of the research was to explore the association between deprivation of socio-economic status (SES) and spatial patterns of COVID-19 incidence in Chennai megacity for unfolding the disease epidemiology.

Study design

This is an ecological (or contextual) study for electoral wards (subcities) of Chennai megacity.

Methods

Using data of confirmed COVID-19 cases from May 15, 2020, to May 21, 2020, for 155 electoral wards obtained from the official website of the Chennai Municipal Corporation, we examined the incidence of COVID-19 using two count regression models, namely, Poisson regression (PR) and negative binomial regression (NBR). As explanatory factors, we considered area deprivation that represented the deprivation of SES. An index of multiple deprivations (IMD) was developed to measure the area deprivation using an advanced local statistic, geographically weighted principal component analysis. Based on the availability of appropriately scaled data, five domains (i.e., poor housing condition, low asset possession, poor availability of WaSH services, lack of household amenities and services, and gender disparity) were selected as components of the IMD in this study.

Results

The hot spot analysis revealed that area deprivation was significantly associated with higher incidences of COVID-19 in Chennai megacity. The high variations (adjusted R²: 72.2%) with the lower Bayesian Information Criteria (BIC) (124.34) and Akaike's Information Criteria (AIC) (112.12) for NBR compared with PR suggests that the NBR model better explains the relationship between area deprivation and COVID-19 incidences in Chennai megacity. NBR with two-sided tests and P <0.05 were considered statistically significant. The outcome of the PR and NBR models suggests that when all other variables were constant, according to NBR, the relative risk (RR) of COVID-19 incidences was 2.19 for the wards with high housing deprivation or, in other words, the wards with high housing deprivation having 119% higher probability (RR = e^0.786 = 2.19, 95% confidence interval [CI] = 1.98 to 2.40), compared with areas with low deprivation. Similarly, in the wards with poor availability of WaSH services, chances of having COVID-19 incidence was 90% higher than in the wards with good WaSH services (RR = e^0.642 = 1.90, 95% CI = 1.79 to 2.00). Spatial risks of COVID-19 were predominantly concentrated in the wards with higher levels of area deprivation, which were mostly located in the northeastern parts of Chennai megacity.

Conclusions

We formulated an area-based IMD, which was substantially related to COVID-19 incidences in Chennai megacity. This study highlights that the risks of COVID-19 tend to be higher in areas with low SES and that the northeastern part of Chennai megacity is predominantly high-risk areas. Our results can guide measures of COVID-19 control and prevention by considering spatial risks and area deprivation.

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COVID-19 cases was modelled using Poisson regression and negative binomial regression.

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An IMD was devised using geographically weighted principal component analysis.

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Area deprivation in Chennai has both positive and inverse associations with the COVID-19.

652The effect of varying irrigation flow rate during irrigated radiofrequency ablation on optimising lesion shape

Funding Acknowledgements

Investigator Sponsored Research grant from Boston Scientific

Introduction

Irrigated catheters are the standard tool for radiofrequency (RF) ablation in the left atrium and ventricles. However, pathological studies of irrigated RF lesions show a "tear-drop" shape, with the widest diameter some depth below the endocardial surface and relative endocardial sparing. This requires overlap of lesions to achieve contiguity at the endocardial surface. There has been little investigation into the effect of altering irrigation rate on lesion shape and volume.

Purpose

To test the hypothesis that varying the irrigation flow rate would optimise lesion shape by minimising endocardial sparing while maintaining lesion depth.

Methods

In an ex vivo animal heart model, irrigated ablation lesions were performed in porcine ventricular tissue at 30W using an Intellatip MiFi OI catheter with 5 different irrigation protocols: A. fixed rate (30ml/min); B. continuous reduction (30 to 2ml/min over 30s); C. continuous increase (2 to 30ml/min over 30s); D. stepwise reduction (30ml/min (10s) to 16ml/min (10s) to 2ml/min (10s)); E. stepwise increase (2ml/min (10s) to 16ml/min (10s) to 30ml/min (10s). Contact force (10g) and ablation duration (30s) were constant. Steam pops during ablation were recorded. Tissue sections were stained with triphenyltetrazolium chloride (TTC) after ablation to allow accurate measurement of lesion boundaries. Surface diameter, lesion depth, maximum diameter, and depth at maximum diameter were measured using Vernier Calipers to calculate lesion volume. Pictures of lesions were analysed further by ImageJ software to measure the degree of endocardial sparing. The optimal protocol was further tested against fixed-rate irrigation at 20W – 40W.

Results

10-20 lesions were performed for each irrigation protocol. Of the 4 experimental protocols, continuous reduction (protocol B) resulted in the most optimal lesion shape (Figure). With this protocol, endocardial sparing area was significantly reduced compared to fixed-rate irrigation (1.61 vs. 2.64mm2, P &lt; 0.0001), with a trend towards an increase in surface diameter (9.25 vs. 8.46mm, P = 0.08). There was no significant difference in lesion depth (5.35 vs. 4.77mm), lesion volume (374 vs. 332mm3) or maximum diameter (10.3 vs. 10.8mm). Steam pop occurred in 1 of 20 (5%) lesions in each of protocols A and B.

Significantly reduced endocardial sparing with preserved volume/depth was consistent for continuous reduction when compared to fixed-rate irrigation across power settings of 20W (17ml/min), 30 W (17ml/min or 30ml/min) and 40W (30ml/min) (P &lt; 0.0001).

Conclusions

Continuous reduction in irrigation flow rate from 30 to 2ml/min during irrigated RF ablation results in reduced endocardial sparing with preserved lesion depth and volume when compared to fixed-rate irrigation across power settings of 20 – 40W. This may allow for greater lesion spacing while maintaining endocardial contiguity and merits further investigation to improve irrigated RF ablation efficiency.

Abstract Figure

664Local catheter impedance drop during pulmonary vein isolation predicts conduction block in patients with paroxysmal atrial fibrillation: initial results of the LOCALIZE clinical trial

Funding Acknowledgements

Boston Scientific

Background

Radiofrequency (RF) catheter ablation for pulmonary vein isolation (PVI) requires resistively heating cardiac tissue to create conduction block. Creation of an RF lesion results in an impedance drop and the magnitude of this drop depends on the temperature and amount of myocardium being heated. Pre-clinical and clinical evaluation of an advanced local impedance (LI) metric found that greater LI drops were indicative of more effective lesion formation.

Purpose

To evaluate whether LI drop is associated with conduction block after first pass encirclement of the PVs in patients with paroxysmal AF.

Methods

LOCALIZE is an ongoing, single-arm, multi-center clinical trial (clinicaltrials.gov NCT03232645). LOCALIZE consists of an index PVI procedure (results presented here) and a 3-month follow-up mapping procedure. In the index procedure, electroanatomical maps of the left atrium were created and ipsilateral PVs were divided into 8 anatomical segments (n = 16 per patient). PVI was performed using point-by-point ablation with blinding of operators to LI. Following initial encirclement and a 20-minute wait period, coronary sinus-paced electroanatomical maps were created to identify gaps within anatomical segments. Gaps were annotated on the map and subsequently ablated. Mean LI drop within each segment was calculated offline as an estimate of regional RF energy delivery (Figure - Left). The diagnostic accuracy of LI drop for predicting segment block was assessed using receiver operating characteristic (ROC) analysis in segments with inter-lesion spacing ≤6mm.

Results

Forty-seven patients with paroxysmal AF underwent PVI at 5 centers (age 62 ± 11 years, male 55.3%). All patients left the index procedure with all PVs isolated. When blinded to LI (n = 3,064 ablations), median baseline LI was 106 (IQR: 97-115) Ω and median LI drop was 18.4 (12.7-24.9) Ω. After first pass encirclement, blocked segments had a significantly larger LI drop (20.2 [14.6-26.0] Ω) than segments with gaps (10.6 [6.9-15.1] Ω, p &lt; 0.01, Figure - Right). The association between LI drop and block was further evaluated along anatomical anterior/posterior wall thickness differences. Anterior block segments were found to have significantly larger LI drops (21.0 [15.9-27.2] Ω) than posterior block segments (16.6 [12.7-23.7] Ω, p &lt; 0.01). ROC analysis of segments with inter-lesion spacing ≤6mm identified optimal LI cut-off values of 16Ω in anterior segments and 11Ω posteriorly, which had positive predictive values for conduction block of 95.6% and 96.7%, respectively.

Conclusions

The magnitude of LI drop is predictive of acute PVI segment conduction block in patients with paroxysmal AF. The thinner posterior wall required smaller LI drops for block compared to the thicker anterior wall. With inter-lesion spacing of ≤6mm, reaching a LI drop of ≥16Ω anteriorly and ≥11Ω posteriorly was highly predictive of acute segment block in de novo PVI.

Abstract Figure. Local impedance drop in de novo PVI

Community engagement interventions for communicable disease control in low- and lower- middle-income countries: evidence from a review of systematic reviews

Background

Community engagement (CE) interventions include a range of approaches to involve communities in the improvement of their health and wellbeing. Working with communities defined by location or some other shared interest, these interventions may be important in assisting equity and reach of communicable disease control (CDC) in low and lower-middle income countries (LLMIC). We conducted an umbrella review to identify approaches to CE in communicable disease control, effectiveness of these approaches, mechanisms and factors influencing success.

Methods

We included systematic reviews that: i) focussed on CE interventions; ii) involved adult community members; iii) included outcomes relevant to communicable diseases in LLMIC; iv) were written in English. Quantitative results were extracted and synthesised narratively. A qualitative synthesis process enabled identification of mechanisms of effect and influencing factors. We followed guidance from the Joanna Briggs Institute, assessed quality with the DARE tool and reported according to standard systematic review methodology.

Results

Thirteen systematic reviews of medium-to-high quality were identified between June and July 2017. Reviews covered the following outcomes: HIV and STIs (6); malaria (2); TB (1); child and maternal health (3) and mixed (1). Approaches included: CE through peer education and community health workers, community empowerment interventions and more general community participation or mobilisation. Techniques included sensitisation with the community and involvement in the identification of resources, intervention development and delivery. Evidence of effectiveness of CE on health outcomes was mixed and quality of primary studies variable. We found: i) significantly reduced neonatal mortality following women’s participatory learning and action groups; ii) significant reductions in HIV and other STIs with empowerment and mobilisation interventions with marginalised groups; iii) significant reductions in malaria incidence or prevalence in a small number of primary studies; iv) significant reductions in infant diarrhoea following community health worker interventions. Mechanisms of impact commonly occurred through social and behavioural processes, particularly: changing social norms, increasing social cohesion and social capacity. Factors influencing effectiveness of CE interventions included extent of population coverage, shared leadership and community control over outcomes.

Conclusion

Community engagement interventions may be effective in supporting CDC in LLMIC. Careful design of CE interventions appropriate to context, disease and community is vital.

Molecular epidemiology, risk factors and hematological evaluation of asymptomatic Theileria annulata infected cattle in Odisha, India

BACKGROUND

Theileria annulata is a tick-borne apicomplexan parasite that affects bovine and causes severe economic losses. Aims: Our study aimed to determine the molecular prevalence of T. annulata infection in asymptomatic carrier cattle in Odisha, India, to study the association of potential risk factors with theileriosis, and to investigate the effect of the parasite infection on hematological parameters in naturally affected animals.

METHODS

A total of 226 cattle blood samples were collected from seven districts of Odisha, India. Molecular diagnoses of tropical theileriosis by polymerase chain reaction (PCR), cloning, sequencing, and phylogenetic analysis of isolated parasites were performed. Potential risk factors were investigated by univariable and multivariable logistic regression statistical analysis. Hematological parameters were compared between positive and negative animals.

RESULTS

All animals included in our study were clinically normal, however, 54.86% (124/226) of examined animals were positive by PCR for T. annulata. The multivariable logistic regression showed that contact with other cattle from different herds during grazing (P<0.0001; OR: 12.75; 95% CI: 5.21-31.21), previous history of clinical signs (P=0.002; OR: 3.31; 95% CI: 1.53-6.31), and frequency of a ectoparasiticides application pre year (P<0.0001; OR: 9.22; 95% CI: 3.03-28.09) were the potential risk factors for the occurrence of tropical theileriosis. Nucleotide sequence identity data demonstrated that T. annulata strain (MN818858) Odisha shared homology of 99.6%, 99.49%, and 99.36% with Uttar Pradesh, India (MF346035), Bahrain (AF214797), and Hyderabad, India (MK034702), respectively.

CONCLUSION

This is the first study to gain insight into the molecular epidemiology, risk factors, phylogeny, and hematological analysis of asymptomatic T. annulata infected cattle from India.

Corrigendum to "Dietary administration of Nexrutine inhibits rat liver tumorigenesis and induces apoptotic cell death in human hepatocellular carcinoma cells". [Toxicol. Rep. 2 (2014) (November) 1-11]

[This corrects the article DOI: 10.1016/j.toxrep.2014.11.006.].