Post-surgical ctDNA-based molecular residual disease detection in patients with stage I uterine malignancies

INTRODUCTION

Among uterine malignancies, endometrial cancer (EC) is the most common cancer of the female reproductive tract. Traditionally, risk stratification in EC is determined by standard clinicopathological risk factors. Although circulating tumor DNA (ctDNA) has emerged as a prognostic biomarker in various malignancies, its clinical validity in EC remains to be established.

METHODS

In this analysis of real-world data, 267 plasma samples from 101 patients with stage I EC were analyzed using a tumor-informed ctDNA assay (Signatera™ bespoke mPCR-NGS). Patients were followed post-surgically and monitored with ctDNA testing for a median of 6.8 months (range: 0.37-19.1).

RESULTS

Patients who tested ctDNA-positive at both their first time point and longitudinally experienced inferior recurrence-free survival (RFS) (HR = 6.2; p = 0.0006 and HR = 15.5; p < 0.0001, respectively), and showed a recurrence rate of 58% and 52%, vs. 6% and 0%, respectively for the ctDNA-negative patients. Most ctDNA-positive patients had high-risk histologies or sarcoma, versus low-risk and high-intermediate risk (H-IR) EC. Furthermore, patients with high-risk histologies who were ctDNA-positive showed shorter RFS compared to those who tested negative (HR = 9.5; p = 0.007), and those who tested positive in the low/H-IR cohort (HR = 0.25; p = 0.04). Post-surgically, detectable ctDNA was highly prognostic of clinical outcome and remained the only significant risk factor for recurrence when adjusted for clinicopathological risk factors, such as histologic risk group, mismatch repair (MMR), and p53 status.

CONCLUSION

Incorporating ctDNA monitoring along with traditional known risk factors may aid in identifying patients with stage I EC who are at highest risk of recurrence, and possibly aid in treatment stratification.

Exploring molecular profiles of calcification in aortic vascular smooth muscle cells and aortic valvular interstitial cells

Cardiovascular calcification can occur in vascular and valvular structures and is commonly associated with calcium deposition and tissue mineralization leading to stiffness and dysfunction. Patients with chronic kidney disease and associated hyperphosphatemia have an elevated risk for coronary artery calcification (CAC) and calcific aortic valve disease (CAVD). However, there is mounting evidence to suggest that the susceptibility and pathobiology of calcification in these two cardiovascular structures may be different, yet clinically they are similarly treated. To better understand diversity in molecular and cellular processes that underlie hyperphosphatemia-induced calcification in vascular and valvular structures, we exposed aortic vascular smooth muscle cells (AVSMCs) and aortic valve interstitial cells (AVICs) to high (2.5 mM) phosphate (Ph) conditions in vitro, and examined cell-specific responses. To further identify hyperphosphatemic-specific responses, parallel studies were performed using osteogenic media (OM) as an alternative calcific stimulus. Consistent with clinical observations made by others, we show that AVSMCs are more susceptible to calcification than AVICs. In addition, bulk RNA-sequencing reveals that AVSMCs and AVICs activate robust ossification-programs in response to high phosphate or OM treatments, however, the signaling pathways, cellular processes and osteogenic-associated markers involved are cell- and treatment-specific. For example, compared to VSMCs, VIC-mediated calcification involves biological processes related to osteo-chondro differentiation and down regulation of 'actin cytoskeleton'-related genes, that are not observed in VSMCs. Furthermore, hyperphosphatemic-induced calcification in AVICs and AVSMCs is independent of P13K signaling, which plays a role in OM-treated cells. Together, this study provides a wealth of information suggesting that the pathogenesis of cardiovascular calcifications is significantly more diverse than previously appreciated.

Longitudinal Monitoring of Circulating Tumor DNA to Assess the Efficacy of Immune Checkpoint Inhibitors in Patients With Advanced Genitourinary Malignancies

PURPOSE

Circulating tumor DNA (ctDNA) detection in blood has emerged as a prognostic and predictive biomarker demonstrating improved assessment of treatment response in patients receiving immune checkpoint inhibitors (ICIs). Here, we performed a pilot study to support the role of ctDNA for longitudinal treatment response monitoring in patients with advanced genitourinary (GU) malignancies receiving ICIs.

MATERIALS AND METHODS

Patients with histologically confirmed advanced GU malignancies were prospectively enrolled. All eligible patients received ICI treatment for at least 12 weeks, followed by serial collection of blood samples every 6-8 weeks and conventional scans approximately every 12 weeks until disease progression. ctDNA analysis was performed using Signatera, a tumor-informed multiplex-polymerase chain reaction next-generation sequencing assay. Overall, the objective response rate (ORR) was reported and its association with ctDNA status was evaluated. Concordance rate between ctDNA dynamics and conventional imaging was also assessed.

RESULTS

ctDNA analysis was performed on 98 banked plasma samples from 20 patients (15 renal, four urothelial, and one prostate). The median follow-up from the time of initiation of ICI to progressive disease (PD) or data cutoff was 67.7 weeks (range, 19.6-169.6). The ORR was 70% (14/20). Eight patients ultimately developed PD. The overall concordance between ctDNA dynamics and radiographic response was observed in 83% (15/18) of patients. Among the three patients with discordant results, two developed CNS metastases and one progressed with extracranial systemic disease while ctDNA remained undetectable.

CONCLUSION

In this pilot study, longitudinal ctDNA analysis for monitoring response to ICI in patients with advanced GU tumors was feasible. Larger prospective studies are warranted to validate the utility of ctDNA as an ICI response monitoring tool in patients with advanced GU malignancies.

Abstract 5600: Utility of circulating tumor DNA and transcriptomic profiling in predicting outcome in muscle invasive bladder cancer patients

Background: Standard treatment of localized muscle invasive bladder cancer (MIBC) is neoadjuvant chemotherapy (NAC) followed by radical cystectomy (RC); however, only 40-50% respond to NAC and approx. 50% experience relapse. Evaluation of treatment efficacy and early detection of relapse are therefore major clinical challenges.

Methods: We present a clinical update of a previously described cohort of 68 patients who received NAC prior to RC (NAC cohort; Christensen et al. JCO 2019; median follow-up (FU) of 58 months) together with evaluation of a retrospectively collected cohort of 120 patients who did not receive NAC (no-NAC cohort; median FU of 71 months). Circulating tumor DNA (ctDNA) was analyzed before NAC (NAC cohort, n=63), prior to RC (NAC cohort, n=67; no-NAC cohort, n=115) and after RC (NAC cohort, n=66; no-NAC cohort, n=37) using Signatera™. RNA-seq was performed on 176 tumors.

Results: Updated clinical FU for the NAC cohort showed that ctDNA-positive patients had significantly worse recurrence-free survival (RFS) compared to ctDNA-negative patients (before NAC: HR=16, 95%CI=3.6-70.5, p=0.0002; during surveillance after RC: HR=27.6, 95%CI=7.9-96.9, p&lt;0.0001). After NAC prior to RC, 84% (52/62) of patients were ctDNA-negative, and of these 81% (42/52) achieved pathological complete response (pCR), while none of the ctDNA-positive patients achieved pCR (PPV 100%; NPV 81%). For the no-NAC cohort, presence of ctDNA was also prognostic at both time points (before RC: HR=2.5, 95%CI=1.4-4.4, p=0.001; single time point after RC: HR=10.1, 95%CI=3.2-31.6, p&lt;0.0001). In both cohorts, transcriptomic pathway analysis showed an enrichment of oncogenic pathways, namely EMT and hypoxia (q&lt;0.0001), in tumors from ctDNA-positive patients (n=62/142). This may reflect a more aggressive cancer phenotype of ctDNA shedding tumors. Among those who were ctDNA-positive after NAC (n=7) we found enrichment of EMT (q&lt;0.0001) and TGF-β signaling (q=0.005), whereas there was enrichment of anti-tumor immune pathways, including IFNα and IFNγ response (q=0.03 and q=0.04), in patients with ctDNA clearance after NAC (n=11). Similarly, we found upregulation of IFNα and IFNγ response pathways (q&lt;0.0001) in ctDNA-negative patients without relapse in the no-NAC cohort (n=34/57). Finally, we classified all tumors according to the MIBC consensus classes and found more Ba/Sq tumors among the ctDNA-positive patients (p&lt;0.0001). We are currently investigating the potential clinical benefit of receiving NAC in ctDNA-positive and -negative patients by comparing the NAC and no-NAC treated patients.

Conclusion: Presence of ctDNA was associated with worse prognosis for both NAC and no-NAC treated patients. Transcriptomic analysis of primary tumors showed that anti-tumor immune responses may be associated with a particularly good outcome whereas EMT may be promoting more aggressive disease.

Citation Format: Sia Viborg Lindskrog, George Laliotis, Karin Birkenkamp-Demtröder, Iver Nordentoft, Philippe Lamy, Elshaddai Z. White, Natalia Pajak, Tine G. Andreasen, Punashi Dutta, Meenakshi Malhotra, Shruti Sharma, Mark Calhoun, Adam ElNaggar, Minetta C. Liu, Mads Agerbæk, Jørgen B. Jensen, Lars Dyrskjøt. Utility of circulating tumor DNA and transcriptomic profiling in predicting outcome in muscle invasive bladder cancer patients. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 5600.

Longitudinal detection of circulating tumor DNA in patients with advanced renal cell carcinoma

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Background: Treatment response monitoring is key to effective disease management for patients with advanced (RCC) and can potentially improve clinical outcomes. Circulating tumor DNA (ctDNA) has shown promise as a biomarker in the early identification of treatment response in a variety of tumor types. Herein, we evaluated ctDNA-derived molecular residual disease (MRD) detection and dynamics in both clear cell (ccRCC) and non-clear cell (nccRCC) RCC patients treated with standard of care therapy and provide correlations with clinical outcomes. Methods: This was a multi-center retrospective analysis of real-world data obtained from commercial ctDNA testing (Signatera, Natera, Inc.), 41 patients (142 plasma samples) with high-risk resected or metastatic RCC were analyzed for ctDNA. Clinical data were collected on IMDC risk category, pathologic subtype, tumor stage and grade including the presence of sarcomatoid/rhabdoid features. Progression on radiological imaging was based on RECIST 1.1. criteria. Results: Of the 41 patients, 73% (30/41) had ccRCC and the remaining 27% (11/41) were nccRCC. Immunotherapy was administered as a single agent or in combination with other immune checkpoint inhibitor agents/targeted therapy in 78% (32/41) in either frontline or refractory settings. ctDNA detection at any time point was 70% (29/41) and patients were followed-up for a median of 26.4 weeks (range: 0.9-90.6) from the first ctDNA time point. Fourteen patients (34%) experienced disease progression during follow-up and all had ctDNA detected ahead of radiological progression (100% sensitivity) with a median lead time of 13.6 weeks (range: 1-39.7 weeks). Concordance between clinical outcome and ctDNA status (detected or not detected) was observed in 78% (32/41) of the patients, 12% (5/41) showed discordance, and imaging data is pending for 10% (4/41) at the time of analysis. Conclusions: Collectively, our study demonstrates high concordance between MRD status and subsequent clinical outcomes. MRD had 100% sensitivity for predicting subsequent radiographic progression with significant median lead time. MRD may serve as a valuable tool for monitoring patients on immunotherapy-based regimens for RCC.

Utility of ctDNA in predicting outcome and pathological complete response in patients with bladder cancer as a guide for selective bladder preservation strategies

563

Background: Muscle-invasive bladder cancer (MIBC) accounts for ~25–30% of all bladder cancer diagnoses. With neoadjuvant chemotherapy (NAC) followed by radical cystectomy (RC) as standard-of-care, the 5-year survival rate ranges from 40%–60%. Bladder-sparing protocols (BSP) have emerged as a feasible alternative to RC for MIBC treatment, however better tools are needed. In this study, we evaluated the prognostic value of circulating tumor DNA (ctDNA) in predicting recurrence in patients who achieved pathological complete response (pCR). Methods: We analyzed a previously described cohort of 68 patients (656 plasma samples; Christensen et al., JCO 2019) with MIBC who received NAC prior to cystectomy. Patients had an updated median follow-up of 58.94 months (range: 7.19-81.77) post-cystectomy. ctDNA was analyzed at baseline (before NAC; N=64), and prior to cystectomy (N=65) using a commercially available assay (Signatera, Natera, Inc.). Additionally, exploratory RNA-Seq was performed on tumors from 59 patients (samples with >5M total counts were utilized). Pathway analysis was used to compare ctDNA-positive and ctDNA-negative patients who failed to achieve pCR. Results: Of the 64 patients with ctDNA results available at baseline, 59.4% (38/64) tested ctDNA-negative, and of these 84.2% (32/38) achieved pCR. Furthermore, 40.6% (26/64) tested ctDNA-positive, and only 34.6% (9/26) achieved pCR. Likewise, prior to cystectomy, 83.9% (52/62) of patients were ctDNA-negative, and 80.7% (42/52) achieved pCR, while none of the ctDNA-positive patients achieved pCR (positive predictive value 100%; negative predictive value 80.8%). Based on both ctDNA timepoints, the probability of ctDNA-negative patients to achieve pCR was significantly higher than ctDNA-positive patients ( p<0.0001). Notably, ctDNA-positive patients without pCR demonstrated significantly poorer RFS and OS compared to the ctDNA-negative patients, at both timepoints (Baseline: RFS; HR=8.2, p=0.017, OS; HR=8.4, p=0.015, prior to cystectomy: RFS; HR=5.2, p=0.0078, OS; HR=4.8, p=0.012). Furthermore, ctDNA status at baseline and before cystectomy was a better predictor of RFS compared to pCR (HR=8.5, p<0.0001, HR=14, p<0.0001, respectively). Transcriptomic pathway analysis of patients who did not achieve pCR showed an enrichment of oncogenic pathways, namely EMT and angiogenesis, in tumors from ctDNA positive patients, whereas tumors from ctDNA negative patients showed an enrichment of anti-tumor immune signatures, including IFNα and IFNγ. Conclusions: Absence of ctDNA was significantly associated with pCR both at baseline and prior to cystectomy, identifying patients who may benefit from BSP. Larger cohorts are warranted to test the prognostic value of ctDNA combined with transcriptomic profiling in informing patient selection for avoiding cystectomy.

Utility of myxedema score as a predictor of mortality in myxedema coma

OBJECTIVE

Myxedema crisis (MC) is a rare condition. There is a dearth of data regarding the predictors of mortality in MC. Predictive scores for mortality specific to the clinical and biochemical profile of MC are still lacking.

DESIGN AND METHODS

All consecutive patients presenting with MC from September 2006 to December 2020 comprised the new cohort. Patients managed between January 1999 and August 2006 comprised the old cohort. Both cohorts were compared for the determination of secular trends. Combined analysis of both the cohorts was done for clinico-demographic profile and predictors of mortality. Myxedema score (MS) and qSOFA (Quick Sequential Organ Failure Assessment) score were evaluated in all the patients.

RESULTS

A total of forty-one patients (new cohort; n = 18 and old cohort; n = 23) were enrolled into the study. There was a female predominance (80.5%). Nearly half (51.2%) of the patients were newly diagnosed with hypothyroidism on admission. Overall mortality was 60.9%. On comparative analysis among survivors and non-survivors, female gender (OR 20.4, p value 0.018), need for mechanical ventilation (OR16.4, p value 0.009), in-hospital hypotension (OR 9.1, p value 0.020), and high qSOFA score (OR 7.1, p value 0.023) predicted mortality. MS of > 90 had significantly higher mortality (OR-11.8, p value - 0.026) while MS of > 110 had 100% mortality. There was no change in secular trends over last 20 years. There was no difference in outcome of patients receiving oral or IV levothyroxine.

CONCLUSION

Myxedema crisis is associated with high mortality despite improvement in health care services. The current study is first to elucidate the role of the MS in predicting mortality in patients with MC.

Mesenchymal Stem Cell Therapy for Patients with Post COVID ARDS on ECMO Referred for Lung Transplantation - Single Center Experience from India

Purpose

India experienced a devastating second wave of the covid 19 pandemic triggered by the delta variant, which peaked in end of April and early May 2021 with average daily new cases hitting 300,000 to 400,000 and daily death toll reaching 3000 to 3500. ECMO emerged as an option for severe post covid ARDS and was offered in many centers across India for patients who were worsening despite full ventilatory support and prone positioning. A small minority of these patients who showed no improvement despite several weeks on ECMO were referred for lung transplantation to our center. Out of the 63 ECMO pts we received for Lung Transplantation 5 patients received Mesenchymal Stem Cell (MSC) infusion over and above standard treatment after getting necessary clearance from hospital Ethics committee and consent from patients’ family

Methods

We conducted a case control study on critically ill post covid ARDS patients on ECMO referred for lung transplantation to our center. 5 patients received 2 million umbilical cord derived MSCs/kgwt infused over 30 minutes, for 3 doses on days 0, 3 and 6 and was compared to other local ECMO patients (control group; n=58). The primary outcome was safety and secondary outcome was all cause mortality.

Results

All 5 patients tolerated MSC infusions well with no side effects observed. Out of the 5 patients who received MSC infusions 3 pts (60%) recovered and were weaned off ECMO successfully. 1 pt (20%) did not improve and expired, 1 pt (20%) did not recover and underwent successful lung transplantation and was discharged home. In the ECMO control group, 15 patients (26%) recovered without transplant, 23 pts (40%) underwent successful lung transplantation and 20 pts (34%) expired.

Conclusion

MSC IV infusion is safe and well tolerated without side effects in covid ARDS pts on ECMO. The efficacy of MSC in repairing the covid destroyed lung should be further evaluated in large randomised controlled studies.

Airway Complications After Lung Transplant for Post Coronaviral Disease (COVID-19) Acute Respiratory Distress Syndrome (ARDS) Related End Stage Lung Disease: Single Centre Experience

Purpose

Severe COVID-19 ARDS related end stage lung fibrosis with irreversible changes is a newer indication for lung transplantation with acceptable survival rate. Airway complication post lung transplant is a major source of morbidity and mortality with incidence as high as 25 to 49 percent. Patients with end stage COVID-19 fibrosis are likely to be clinically deconditioned with long duration of extracorporeal oxygenator (ECMO) support, high burden of sepsis and prolonged respiratory support which may affect the airways post lung transplantation.

Methods

This is a retrospective observational study after obtaining institutional ethical clearance. We reviewed electronic medical data of patients who underwent lung transplantation for post COVID-19 ARDS related fibrosis. We evaluated the incidence and type of airway complications and the various therapeutic interventions applied for its management.

Results

Between May 2020 and September 2021 our centre performed 23 bilateral lung transplants for end stage COVID-19 ARDS related fibrosis. 22 patients were on ECMO support with mean duration of 50.9 days before transplantation. All patients underwent lung transplantation with central Veno-Arterial ECMO support with mean organ ischaemia time of 360±154 minutes. The incidence of airway complication in our study group was 56%. We observed anastomotic narrowing in 3(13%), distal airway narrowing in 4(17%) and sloughing/coating of anastomotic site in 5(22%) patients. Nonspecific inflammatory polypi around the bronchial anastomotic site were noticed in 4(17%) and mild airway anastomotic dehiscence in 2 subjects. 8(34%) patients required serial bronchoscopy and balloon dilatation; 2 among them mandated additional cautery usage. 2 cases underwent polypectomy, further 4 subjects needed bronchial stent placement. 5 (21%) recipients were discharged with Tracheostomy while rest were successfully decannulated in the ward.

Conclusion

We observed a high incidence of airway complications in post lung transplant for COVID-19 ARDS related fibrosis. Early detection, timely management and serial follow up is of paramount importance in this subset of patients.

Tgfβ1-Cthrc1 Signaling Plays an Important Role in the Short-Term Reparative Response to Heart Valve Endothelial Injury

OBJECTIVE

Aortic valve disease is a common worldwide health burden with limited treatment options. Studies have shown that the valve endothelium is critical for structure-function relationships, and disease is associated with its dysfunction, damage, or injury. Therefore, therapeutic targets to maintain a healthy endothelium or repair damaged endothelial cells could hold promise. In this current study, we utilize a surgical mouse model of heart valve endothelial cell injury to study the short-term response at molecular and cellular levels. The goal is to determine if the native heart valve exhibits a reparative response to injury and identify the mechanisms underlying this process. Approach and Results: Mild aortic valve endothelial injury and abrogated function was evoked by inserting a guidewire down the carotid artery of young (3 months) and aging (16-18 months) wild-type mice. Short-term cellular responses were examined at 6 hours, 48 hours, and 4 weeks following injury, whereas molecular profiles were determined after 48 hours by RNA-sequencing. Within 48 hours following endothelial injury, young wild-type mice restore endothelial barrier function in association with increased cell proliferation, and upregulation of transforming growth factor beta 1 (Tgfβ1) and the glycoprotein, collagen triple helix repeat containing 1 (Cthrc1). Interestingly, this beneficial response to injury was not observed in aging mice with known underlying endothelial dysfunction.

CONCLUSIONS

Data from this study suggests that the healthy valve has the capacity to respond to mild endothelial injury, which in short term has beneficial effects on restoring endothelial barrier function through acute activation of the Tgfβ1-Cthrc1 signaling axis and cell proliferation.

Remission in Cushing's disease is predicted by cortisol burden and its withdrawal following pituitary surgery

AIM

To ascertain the predictors of remission and relapse in patients of Cushing's disease (CD) undergoing pituitary transsphenoidal surgery (TSS).

METHODS

Patients with CD subjected to TSS over 35 years at a tertiary care center were included. Patients were grouped into remission and persistent disease at 1 year after surgery, and were further followed up for relapse. Demographic, clinical, biochemical, histological, radiological and post-operative follow-up parameters were analyzed.

RESULTS

Of the 152 patients of CD, 145 underwent TSS. Remission was achieved in 95 (65.5%) patients at 1 year. Patients in remission had shorter duration of symptoms prior to presentation (p = 0.009), more frequent presence of proximal myopathy (p = 0.038) and a tumor size of < 2.05 cm (p = 0.016) in comparison to those with persistent disease. Post-TSS, immediate post-operative 0800-h cortisol (< 159.85 nmol/L; p = 0.001), histological confirmation of tumor (p = 0.045), duration of glucocorticoid replacement (median 90 days; p = 0.001), non-visualization of tumor on MRI (p = 0.003), new-onset hypogonadism (p = 0.001), 3-month 0800-h cortisol (< 384.9 nmol/L; p = 0.001), resolution of diabetes (p = 0.001) and hypertension (p = 0.001), and recovery of hypothalamic-pituitary-adrenal axis (p = 0.018) favored remission. In logistic regression model, requirement of glucocorticoid replacement (p = 0.033), and resolution of hypertension post-TSS (p = 0.003) predicted remission. None of the parameters could predict relapse.

CONCLUSION

The study could ascertain the predictors of remission in CD. Apart from the tumor characteristics, surgical aspects and low post-operative 0800-h cortisol, the results suggest that baseline clinical parameters, longer glucocorticoid replacement, and resolution of metabolic complications post-TSS predict remission in CD. Long-term follow-up is essential to look for relapse.

KPT-330 Prevents Aortic Valve Calcification via a Novel C/EBPβ Signaling Pathway

[Figure: see text].

Genetic and Developmental Contributors to Aortic Stenosis

Aortic stenosis (AS) remains one of the most common forms of valve disease, with significant impact on patient survival. The disease is characterized by left ventricular outflow obstruction and encompasses a series of stenotic lesions starting from the left ventricular outflow tract to the descending aorta. Obstructions may be subvalvar, valvar, or supravalvar and can be present at birth (congenital) or acquired later in life. Bicuspid aortic valve, whereby the aortic valve forms with two instead of three cusps, is the most common cause of AS in younger patients due to primary anatomic narrowing of the valve. In addition, the secondary onset of premature calcification, likely induced by altered hemodynamics, further obstructs left ventricular outflow in bicuspid aortic valve patients. In adults, degenerative AS involves progressive calcification of an anatomically normal, tricuspid aortic valve and is attributed to lifelong exposure to multifactoral risk factors and physiological wear-and-tear that negatively impacts valve structure-function relationships. AS continues to be the most frequent valvular disease that requires intervention, and aortic valve replacement is the standard treatment for patients with severe or symptomatic AS. While the positive impacts of surgical interventions are well documented, the financial burden, the potential need for repeated procedures, and operative risks are substantial. In addition, the clinical management of asymptomatic patients remains controversial. Therefore, there is a critical need to develop alternative approaches to prevent the progression of left ventricular outflow obstruction, especially in valvar lesions. This review summarizes our current understandings of AS cause; beginning with developmental origins of congenital valve disease, and leading into the multifactorial nature of AS in the adult population.

Health risks from PAHs and potentially toxic elements in street dust of a coal mining area in India

Polycyclic aromatic hydrocarbons (PAHs) and potentially toxic elements (PTEs) (Ba, Zn, Pb, Cu, Cr, Ni, As, Co) were determined in the road dusts of a coal mining area (Dhanbad, India) to assess their content and potential human health risks. Dust samples were collected from sign boards of the heavy traffic road connecting Dhanbad and Sindri. The total PAHs (∑PAHs, all values in mg/kg) content in the road dust samples varied from 3.98 to 13.1, with carcinogenic PAHs content of 14.8-34.4% of the ∑PAHs. Phenanthrene (2.72), fluorene (0.715) and pyrene (0.575) are the major PAHs. Principal component analysis revealed that these PAHs are probably originated from pyrogenic (coal combustion and traffic emission) and petrogenic (coal dust, tyre and road particles) sources. Among the PTEs, the mean content was higher for Ba (293 mg/kg) followed by Zn (224), Pb (128), Cu (52.6), Cr (45.2), Ni (22.0), As (17.5) and Co (8.11). The overall pollution load index varied from 0.43 to 1.0. Source analysis showed that PTEs in the road dust of the study site were derived from traffic emission (Zn, Fe, Mn, Co and Pb), coal dust (Cr, As and Ni) and soil (K, Mg, Ba, Sr and Ca). In general, the PTEs are lower, but the PAHs contents were elevated in the road dust samples. Although the exposure risks from PTEs are low, the risk to children (expressed as hazardous quotient) for As and Pb is near to the permissible limit of 1.0. Cancer risk from PAHs for adult (4.8 × 10^-6) and child (5.3 × 10^-6) has exceeded the acceptable limit of 10^-6.

Metamagnetic transition and observation of spin-fluctuations in the antiferromagnetic Heusler compound Pd2MnIn

We report detailed investigations on the structural, magnetic, magneto-transport and calorimetric aspects of a partially ordered Heusler compound Pd₂MnIn. The sample shows antiferomagnetic (AFM) state below around 120 K, though positive paramagnetic Curie temperature signifies a complex magnetic ground state with the presence of both ferromagnetic (FM) and AFM correlations. A clear spin-flop type metamagnetic transition is observed as evident from the magnetization and resistivity data. However, non-saturation of magnetization even at 145 kOe of applied field implies that the high field state may be a spin canted state, originating from the enhanced FM correlations by field induced conduction electron spin polarization. The sample shows a profound quadratic temperature dependence of resistivity below about 20-25 K indicating a spin-fluctuation dominated low temperature region. Previous electronic structure calculations show the existence of a subtle balance between superexchange mediated AFM state and an RKKY (Ruderman-Kittel-Kasuya-Yoshida) interaction mediated FM state in Pd₂MnIn. Such competing AFM-FM correlations can be accounted for the observed spin fluctuations.

Effect of Linagliptin on Incretin-axis and Glycaemic Variability in T1DM

BACKGROUNDS AND OBJECTIVES

Short-term studies have demonstrated potential therapeutic efficacy of dipeptidyl peptidase 4 inhibitors (DPP4 inhibitors) in patients with poorly controlled T1DM. In this study we evaluated the effect of DPP4 inhibitor, linagliptin, on glycaemic control and variability, and incretinaxis in well controlled T1DM patients to mitigate the effect of glucotoxicity on incretin secreting cells.

METHODS

Twenty T1DM patients were randomized to receive either linagliptin (10 patients, dose-5 mg/day) or placebo (10 patients), in addition to insulin for 3 months. HbA1C, continuous glucose monitoring (CGM) and mixed meal test (MMT) were performed before and at the end of the study period.

RESULTS

HbA1C reduction and change in glycaemic variability and insulin requirement in the linagliptin group did not attain the level of statistical significance. The increase in AUC GLP1 (Area under curve for GLP1) and decrease in AUC glucagon (Area under curve for glucagon) during the MMT in linagliptin group were also statistically insignificant.

INTERPRETATIONS AND CONCLUSIONS

Linagliptin is not effective in reducing HbA1C and glycaemic variability in relatively well controlled T1DM patients.

First report of Chikungunya virus circulation during a dengue outbreak in Arunachal Pradesh, a Northeastern state of India

Dengue has become a major public health problem in Pasighat, Arunachal Pradesh since 2012 outbreak. This region is rich in Aedes mosquitoes, the common vector for Dengue and Chikungunya (CHIK), however, active surveillance of CHIK is lacking in this part of India. Therefore, this study has been undertaken to detect the presence of CHIKV infection during 2014 and 2015 dengue outbreak in Arunachal Pradesh. A total of 116 (52 during 2014 and 64 during 2015 outbreak) dengue negative serum samples were collected from General Hospital, Pasighat and were screened for the presence of CHIK IgM antibodies. All the samples were further processed for CHIKV RNA detection by RT-PCR using specific primers. Phylogenetic tree was constructed by Neighbor Joining method using Kimura-2 parameter model. A total of 8 samples were found to be positive for IgM antibodies. RT-PCR showed CHIKV RNA positivity in 2 samples. Both of these samples belonged to 2014 outbreak. Phylogenetic tree revealed that the CHIKV circulating during the outbreak belonged to Eastern, Central and Southern African genotype. Sequence analysis showed two uniform nucleotide substitutions. Circulation of CHIKV masked by dengue is reported from this study. Therefore, CHIKV diagnosis should be made as a routine test in areas where dengue is already endemic so as to prevent misdiagnosis of the disease and to check its accomplishment before commencing an outbreak.

Glassy magnetic ground state and Kondo-like behaviour in Mn10FeGe8 alloy

We report a detailed investigation of the ground-state magnetic properties of newly synthesized [Formula: see text] [Formula: see text] alloy. The sample can be thought of being derived by substituting one Mn atom by Fe of the parent compound [Formula: see text] [Formula: see text]. Fe-substitution leads to a drastic change in the magnetic ground state as well as to the magneto-transport properties of the parent alloy. On cooling below 250 K, [Formula: see text] [Formula: see text] undergoes a transition from paramagnetic phase to a state having significant ferromagnetic correlations. The ground state is found to be canonical spin glass (CSG) type in nature as evident from the dc magnetization and ac susceptibility measurements. Interestingly, the resistivity data shows an upturn at low temperature below about 30 K, mimicking Kondo-like behaviour. [Formula: see text] [Formula: see text] turns out to be a rare example among 3d transition metal alloys, where a Kondo-like state coexists within a CSG phase.

Effect of Skin Application of Dorogov's Antiseptic-Stimulant on Behavioral Reactions in Rats

Local application of the Dorogov's antiseptic-stimulant onto the skin of 2-month-old male Sprague-Dawley rats in a low dose (0.5 g/kg/day) for 1 week increased motor and ultrasonic activity of experimental animals and the content of activated c-Fos⁺ neurons on the cingular, motor, insular, and pyriform cortex and in the striatum.

The inheritance of juvenile onset primary open angle glaucoma

Juvenile onset open angle glaucoma (JOAG) affects patients before 40 years of age, who present with high intraocular pressure and deep steep cupping of the optic nerve head. While it was considered to be inherited in an autosomal dominant fashion, recent studies have shown an autosomal recessive pattern as well as sporadic occurrence of the disease in several families. In this review, we analyze the genetic basis of the disease along with common mutations and their association with JOAG. We also analyzed the inheritance patterns in a large group of unrelated JOAG patients (n = 336) from Northern India wherein the prevalence of familial occurrence was assessed and segregation analysis performed, to determine the mode of inheritance.

Prevalence of lymphatic filariasis in a tea garden worker population of Dibrugarh (Assam), India after six rounds of mass drug administration

BACKGROUND & OBJECTIVES

Lymphatic filariasis (LF) is endemic in the state of Assam and mass drug administration (MDA) programme for LF elimination is being implemented in the state since 2004. A study on prevalence of microfilaria (mf), disease endemicity and vector infection was carried out in a tea garden population of Dibrugarh, Assam (India) to assess the effect of ongoing MDA programme on elimination of LF.

METHODS

Finger prick thick blood smears (20 mm3) were made from individuals aged ≥2 yr old during night blood survey in between 2000-0000 hrs during the period of November 2012 to February 2013. Blood smears were dehaemoglobinised, stained with Giemsa and examined under microscope for presence of mf. Indoor resting mosquitoes were collected during 0600-1000 hrs and female Culex quinquefasciatus were dissected and examined under microscope for larval forms of the parasite.

RESULTS

A total of 634 blood smears were collected and screened for mf and 47 (7.41%) individuals were found microfilaraemic, with predominance of males (74.5%). Highest mf rate (20.0%) was seen in the males of 30-39 yr age group while in females, age group of 10-19 yr recorded maximum mf rate (5.48%). Entomological collection and dissection of Cx. quinquefasciatus revealed presence of larval stages of the parasite and infection and infectivity rates recorded were 13.20 and 3.70%, respectively. Chronic clinical manifestations in the form of elephantiasis and hydrocele were recorded in 33 (5.73%) subjects of the 575 examined.

INTERPRETATION & CONCLUSION

Mass drug administration data showed six rounds of MDA with drug distribution coverage in between 63.42 and 95.93% in the study population. Out of 634 individuals examined 47 were found microfilaraemic giving an overall infection rate of 7.41%. Mosquito vector infection and infectivity rates were 13.20 and 3.70%, respectively. Presence of high mf rate, vector infectivity rate and clinical cases in the study population after six rounds of MDA warrants concerted efforts to be made for effective implementation and monitoring of MDA for success of LF elimination programme.

Genetic polymorphisms associated with sulphadoxine-pyrimethamine drug resistance among Plasmodium falciparum field isolates in malaria endemic areas of Assam

Background:

The emergence of antimalarial drug resistance malaria parasite is widespread in North eastern region of India. During January 2012-December 2013, we conducted active surveillance for detection of antifolate resistance-associated genetic polymorphisms in Plasmodium falciparum malaria parasite from different malaria endemic areas of Assam.

Materials and Methods:

A total of 281 field samples were collected from suspected malaria patients of which 106 malaria P. falciparum positive cases were detected in microscopic slide examination. A nested PCR was done for amplification of a 648 bp portion of the dhfr gene and 710 bp portion of the dhps gene.

Results:

Mutation analysis revealed existence of three different haplotypes of the P. falciparum dhfr gene of which ANRNI was highly prevalent (90%). Triple mutant haplotypes AIRNI (N51I + C59R + S108N) of the dhfr gene associated with pyrimethamine resistance were prevalent in Chirang district of Assam. Whereas, dhps mutation study revealed that triple mutant haplotype AGEAA (S436A + A437G + K540E) associated with Sulphadoxine resistance was found among 26% of P. falciparum field isolates. However, P. falciparum dhfr-dhps two locus mutation analysis showed that there were a total of nine dhfr-dhps genotypes.

Conclusion:

It was noticed that 93.62% (88/94) isolates had mutations in the sequences of both enzymes, which is an indication of prevalence of high grade of Sulphadoxine — pyrimethamine resistance in P. falciparum malaria parasites in Assam.

Microfilarial periodicity of Wuchereria bancrofti in Assam, Northeast India

BACKGROUND & OBJECTIVES

Wuchereria bancrofti has shown nocturnal periodicity in India and other endemic countries of the world except pacific regions where non-periodic or diurnal sub-periodic forms have been reported. Presence of sub-periodic form of W. bancrofti in Andaman and Nicobar Islands, India and a case report of sub- periodic form of W. bancrofti from Mysore, India provide basis for exploring the periodicity pattern of microfilaria of W. bancrofti prevalent in Assam, Northeastern region of India. State of Assam has unique geographical location as its Northeastern region shares international boundaries with Nepal, China, Bhutan, Myanmar and Bangladesh. Evolutionary association of W. bancrofti found in Assam is not known and possibility of its link with W. bancrofti form, prevalent in neighbouring countries may not be ruled out. Hence, this study was undertaken to know the microfilarial periodicity of W. bancrofti in Assam.

METHODS

Ten microfilaria positive adult male individuals having moderate to high microfilaraemia were selected. Informed written consent from each participant was obtained. The presence of microfilaria was observed at two hourly intervals over a period of 24 h using 50 μl of finger prick peripheral blood samples. Peripheral blood smears were processed, stained and examined under microscope and microfilaria counts were recorded.

RESULTS

Data collected were calculated and analyzed using modified statistical method, and the periodicity curve was prepared. Typical nocturnal periodicity was observed at a peak time of 0003 hrs with a periodicity index of 136.2.

INTERPRETATION & CONCLUSION

Analysis of the data revealed nocturnal periodicity of the W. bancrofti prevalent in the Assam with peak periodicity about one hour ahead of the other states in India. Findings will be helpful in evaluation and monitoring of ongoing MDA programme for elimination of LF in Assam.

Population genetic study of Plasmodium falciparum parasites pertaining to dhps gene sequence in malaria endemic areas of Assam

Plasmodium falciparum malaria parasite had developed resistance to almost all the currently used antimalarial drugs. The purpose of the study was to come across the genetic distances in P. falciparum dhps gene sequences circulating in Assam. A partial fragment of P. falciparum dhps gene containing major single nucleotide polymorphisms associated with sulphadoxine resistance were amplified and sequenced. Thereafter specific bioinformatics tools like BioEdit v7.0.9, ClustalW in Mega 5, DnaSP version v.5.10.01 etc were used for the analysis. A total of 100 P. falciparum positive cases in different malaria endemic areas of Assam were included for the study. Based upon the mutation analysis, a total of seven different P. falciparum dhps genotypes were observed with five variable sites. Maximum five haplotypes were found in the P. falciparum isolates from Jorhat district of Assam. Four polymorphic sites were observed in the P. falciparum dhps gene sequences in Karbi Anglong, NC Hills, Chirang and Jorhat whereas the isolates from other study areas had three polymorphic sites. A statistically significant positive value of Tajima's D were observed among the P. falciparum field isolates in Assam indicating that there is an excess of intermediate frequency alleles and can result from population bottlenecks, structure and/or balancing selection. Extensive gene flow took place among the P. falciparum population of Jorhat with Sivasagar, Chirang with Sivasagar and Chirang with Karbi Anglong. However, large genetic differentiation was observed among the P. falciparum isolates of NC Hills with Lakhimpur, Tinsukia, Dibrugarh and Golaghat and also the parasite population of Karbi Anglong with Lakhimpur and Tinsukia signifying little gene flow among the population. This finding has shown that mutant Pfdhps gene associated with sulphadoxine resistance is circulating in Assam. It is believed that, the parasite population may have undergone high level of breeding.