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Background: Biodosimetry is the quantification of absorbed radiation dose using biological material obtained from an exposed individual. Radiation can cause different types of chromosomal aberrations, including stable aberrations like translocations and unstable ones like micronuclei, dicentric chromosomes (DC), acentric, and ring forms. Dicentric chromosome assay has become the "gold standard" for cytogenetic biodosimetry due to its reproducibility, specificity (low baseline rates), and sensitivity to low doses. Using existing calibration curves and models obtained from in vitro irradiation of blood, the yield of DCs can be used to estimate the average whole-body absorbed dose. Purpose: To evaluate and compare the in vivo dose-response relation of DC aberration formation in peripheral blood lymphocytes of head and neck cancer (HNC) patients undergoing radiotherapy (RT) alone, cisplatin-based chemoradiation (CCRT), accelerated fractionation RT (AFRT), and CCRT with gefitinib (GCRT). Methodology: This prospective observational and analytical study was conducted from 2018 to 2021 in the Department of Radiation Oncology and Genetic Lab of tertiary care, teaching hospital after approval from the Institutional Ethics Committee. Biodosimetric analysis was done weekly in patients undergoing RT (n = 20) versus CCRT (n = 20), CCRT (n = 12) versus AFRT (n = 12), and CCRT (n = 6) versus GCRT (n = 6). The yield of DCs was measured in blood samples taken before starting treatment, that is, day 0 and during RT on days 6, 11, and 16 in RT alone versus CCRT; on days 7 and 13 in CCRT versus AFRT; and days 6 and 11 in CCRT versus GCRT from a blood sample drawn 1-2 h after RT. Phytohemagglutinin-stimulated lymphocytes were cultured using heparinized blood in RPMI-1640 medium supplemented with fetal bovine serum. Cells were arrested at metaphase using demecolcine, harvested by centrifugation, mounted, and stained with Giemsa. Cytogenetic analysis was performed by analyzing at least 100 metaphases with well-spread chromosomes. DC aberrations and acentric fragments were identified and recorded. To standardize the findings as per the customized field for every patient, the mean DC yield per cm² of the irradiated area was calculated and compared. Results: The mean yield of DC/cm² in the CCRT group was greater than the RT alone group by 16.33%, 28.57%, and 18.68% on days 6, 11, and 16 of treatment, respectively. This difference between the two groups at day 6 (P = 0.001), day 11 (P < 0.001), and day 16 (P < 0.001) was found to be statistically significant. The mean yield of DC/cm² in the CCRT group was greater than the AFRT group by 7.9% and 18.3% on days 7 and 13 of treatment, respectively. This difference at day 7 (P < 0.001) and day 13 (P < 0.001) was found to be statistically significant. The mean yield of DC/cm² in the CCRT group was greater than the GCRT group by 22.7% and 21.8% on days 6 and 11 of treatment, respectively. The difference at day 6 (P = 0.01) was statistically significant but, on day 11 (P = 0.065) this difference was found insignificant. Conclusion: There is a dose-dependent increase in the yield of DCs in lymphocytes of HNC patients undergoing RT with subsequent fractions. Cisplatin-based chemoradiation is the superior method of treatment intensification radio-biologically proven by higher DC yield. [ABSTRACT FROM AUTHOR]

Background Simultaneous left ventricular (LV) and aortic (Ao) pressure gradient assessment has been rendered challenging since the recall of the Langston catheter. Here we describe a simple method for simultaneous LV and Ao pressure gradient assessment using a Swan-Ganz catheter. Case summary We describe two cases where assessment of simultaneous left ventricle and Ao valve gradients was done using a Swan-Ganz catheter to assess the degree of Ao stenosis and dynamic LV outflow obstruction. Discussion Using Swan-Ganz catheter assessment of simultaneous left ventricle and Ao valve gradients can simplify the procedure with reduced cost and increased patient safety. [ABSTRACT FROM AUTHOR]

Management of patients on long-term anticoagulation requiring percutaneous coronary intervention is challenging. Triple therapy with oral anticoagulant and dual antiplatelet therapy is the standard of care. However, there is no strong evidence to support this strategy. There is emerging data regarding the safety and efficacy of dual therapy with oral anticoagulant and single antiplatelet therapy in these patients. In this comprehensive review we highlight available evidence regarding various antithrombotic regimens’ efficacy and safety in patient with coronary artery disease undergoing percutaneous coronary intervention with long-term anticoagulation therapy requirements. [ABSTRACT FROM AUTHOR]

Background: Complete revascularization of patients with ST-elevation myocardial infarction and multivessel coronary artery disease reduces adverse events compared to infarct-related artery only revascularization. Whether complete revascularization should be done as multivessel intervention during index procedure or as a staged procedure remains controversial.Method: We performed a meta-analysis of randomized controlled trials comparing outcomes of multivessel intervention in patients with ST-elevation myocardial infarction and multivessel coronary artery disease as staged procedure versus at the time of index procedure. Composite of death or myocardial infarction was the primary outcome. Mantel-Haenszel risk ratios were calculated using random effect model.Results: Six randomized studies with a total of 1126 patients met our selection criteria. At a mean follow-up of 13 months, composite of myocardial infarction or death (7.2% vs 11.7%, RR: 1.66, 95%CI: 1.09-2.52, P = 0.02), all cause mortality (RR: 2.55, 95%CI: 1.42-4.58, P < 0.01), cardiovascular mortality (RR: 2.8, 95%CI: 1.33-5.86, P = 0.01), and short-term (<30 days) mortality (RR: 3.54, 95%CI: 1.51-8.29, P < 0.01) occurred less often in staged versus index procedure multivessel revascularization. There was no difference in major adverse cardiac events (RR: 1.14, 95%CI: 0.88-1.49, P = 0.33), repeat myocardial infarction (RR: 1.14, 95%CI: 0.68-1.92, P = 0.61), and repeat revascularization (RR: 0.92, 95%CI: 0.66-1.28, P = 0.62).Conclusion: In patients with ST-elevation myocardial infarction and multivessel coronary artery disease, a strategy of complete revascularization as a staged procedure compared to index procedure revascularization results in reduced mortality without an increase in repeat myocardial infarction or need for repeat revascularization. [ABSTRACT FROM AUTHOR]

DNA nanotechnology enables the synthesis of nanometer-sized objects that can be site-specifically functionalized with a large variety of materials. For these reasons, DNA-based devices such as DNA origami are being considered for applications in molecular biology and nanomedicine. However, many DNA structures need a higher ionic strength than that of common cell culture buffers or bodily fluids to maintain their integrity and can be degraded quickly by nucleases. To overcome these deficiencies, we coated several different DNA origami structures with a cationic poly(ethylene glycol)-polylysine block copolymer, which electrostatically covered the DNA nanostructures to form DNA origami polyplex micelles (DOPMs). This straightforward, cost-effective, and robust route to protect DNA-based structures could therefore enable applications in biology and nanomedicine where unprotected DNA origami would be degraded. [ABSTRACT FROM AUTHOR]

DNA nanotechnology enables the synthesis of nanometer-sized objects that can be site-specifically functionalized with a large variety of materials. For these reasons, DNA-based devices such as DNA origami are being considered for applications in molecular biology and nanomedicine. However, many DNA structures need a higher ionic strength than that of common cell culture buffers or bodily fluids to maintain their integrity and can be degraded quickly by nucleases. To overcome these deficiencies, we coated several different DNA origami structures with a cationic poly(ethylene glycol)-polylysine block copolymer, which electrostatically covered the DNA nanostructures to form DNA origami polyplex micelles (DOPMs). This straightforward, cost-effective, and robust route to protect DNA-based structures could therefore enable applications in biology and nanomedicine where unprotected DNA origami would be degraded. [ABSTRACT FROM AUTHOR]

Objective: Use of surgical energy is integral to laparoscopic surgery (LS). Energized dissection (ED) has a potential to impact the biomolecular expression of inflammation due to ED-induced collateral inflammation. We did this triple-blind randomized controlled (RCT) study to assess this biomolecular footprint in an index LS, i.e., laparoscopic cholecystectomy (LC).Methods and Procedures: This RCT was conducted in collaboration with tertiary-level institutions, from January 2014 to December 2014 with institutional review board clearance. Consecutive, unselected, consenting candidates for LC were randomized (after anesthesia induction) into group I (ED) and group II (non-ED). They were managed with compliance to universal protocols for ethics, informed consent, anesthesia, drug usage and clinical pathway with blinded observers. Biomolecular inflammatory markers, i.e., interleukin 6 (IL-6), tumor necrosis factor-alpha (TNF-α) and highly sensitive CRP (HS-CRP), were measured with blood drawn juxta-preoperatively (H0), at 4 h (H4) and at 24 h (H24). The quantitative changes induced by ED on IL-6, TNF-α and HS-CRP at H0, H4 and H24 with their kinetic behavior were the study endpoint. Prospective data were analyzed statistically with a p value of <0.05 being significant.Results: Two cases from the ED group had biliary injury and hence were withdrawn from analysis. The ED (n = 49) and non-ED (n = 51) groups had similar demographic, clinical and H0 biomolecular variables. There was a significant increase in IL-6, TNF-α and HS-CRP from H0 to H4 in both the groups (p values <0.001). From H4 to H24, all three cytokines showed significant increase in ED group (p < 0.05), whereas in the non-ED group, IL-6 showed significant fall (p = 0.004) and TNF-α showed no significant change (p = 0.063). Both the groups showed H4-H24 elevation of HS-CRP (p = 0.000).Conclusion: Energized dissection adds to the cytokine-mediated postoperative inflammation. The additional ED-induced inflammation can be measured objectively by IL-6 and TNF-α levels.Clinical Trials Registry: Clinical Trials Registry, India (REF/2014/06/007153). [ABSTRACT FROM AUTHOR]

Success in any profession has no well-defined predictors. Knowledge, skills, training, and talent come in plenty but fail at times to achieve the universal goal of success. Some attribute it to luck. Apart from the tangible ingredients of a successful career, the intangibles like luck or something ill-defined is a real challenge. The intangibles seem like a chasm, an abyss, or a phantom obstacle. Presence of a guiding spirit who can handhold you to overcome these is essential for success. The aim of a professional is to learn, earn, and yearn for creativity. Practice of surgery is an ideal career to pursue the learning, earning, and yearning. More than any other profession, the guiding handholding spirit is required in surgical profession, the concept of mentoring. Originating from the Greco-Roman times when kind Odysseus left his son Telemachus under the care of his friend, mentor, it has become a universal defining necessity for a successful career in surgery. Indian history replete with such examples of mentorship, good as in the case of Dronacharya to Kaurvas but bad as denied by an able, competent, aspiring student like Eklavya. In the medical profession, there are very few Indian role models of mentorship. One name that comes to our mind is Dr. Krishan Mahajan. The more said is less revealed about him. “Knife before wife” was his commonly spoken advice to all who sought his mentorship. “Hard work is not easy but it is fair” so said a famous boxer, Larry Holmes. It is more than true for our profession as it is better to prepare and prevent, rather than repair and repent. [ABSTRACT FROM AUTHOR]

Around 100,000 medical conferences are organized all over the world and hence, they form an integral part of a medical professional's life. Oral presentations, especially award sessions, are judged by a panel of faculty judges who score individual presentations on various aspects including content, delivery and submission. Our objective was to compare the scores given by student-judges and faculty-judges for scientific presentations using the standardized score sheet. An objective, structured score-sheet was designed using existing literature. Five presentations, all made using PowerPoint, were judged using the structured score-sheet by seven student-judges and two-faculty judges. The mean score of all the score-sheets ( n = 45) was 38.5 + 5.4 (out of a maximum score of 50). There was no statistical difference between mean scores assigned by students or faculty ( p = 0.2). Thus, an objective, structured score sheet like ours, when used to judge scientific presentations, gave uniform results even when judges hailed from different levels of the medical hierarchy. [ABSTRACT FROM AUTHOR]

Blood vessels are subjected to numerous biomechanical forces that work harmoniously but, when unbalanced because of vascular smooth muscle cell (vSMC) dysfunction, can trigger a wide range of ailments such as cerebrovascular, peripheral artery, and coronary artery diseases. Human pluripotent stem cells (hPSCs) serve as useful therapeutic tools that may help provide insight on the effect that such biomechanical stimuli have on vSMC function and differentiation. In this study, we aimed to examine the effect of biomechanical strain on vSMCs derived from hPSCs. The effects of two types of tensile strain on hPSC-vSMC derivatives at different stages of differentiation were examined. The derivatives included smooth muscle-like cells (SMLCs), mature SMLCs, and contractile vSMCs. All vSMC derivatives aligned perpendicularly to the direction of cyclic uniaxial strain. Serum deprivation and shortterm uniaxial strain had a synergistic effect in enhancing collagen type I, fibronectin, and elastin gene expression. Furthermore, long-term uniaxial strain deterred collagen type III gene expression, whereas long-term circumferential strain upregulated both collagen type III and elastin gene expression. Finally, long-term uniaxial strain downregulated extracellular matrix (ECM) expression in more mature vSMC derivatives while upregulating elastin in less mature vSMC derivatives. Overall, our findings suggest that in vitro application of both cyclic uniaxial and circumferential tensile strain on hPSC-vSMC derivatives induces cell alignment and affects ECM gene expression. Therefore, mechanical stimulation of hPSC-vSMC derivatives using tensile strain may be important in modulating the phenotype and thus the function of vSMCs in tissue-engineered vessels. [ABSTRACT FROM AUTHOR]

Objective: Laparoscopic cholecystectomy (LC), a gold standard procedure can be done without energized dissection (ED). We did a randomized study for the outcomes of LC done with ED or without ED, i.e., with cold dissection (CD). Methods and Procedures: At a tertiary level institution, open-ended prospective-randomized control study was conducted between September 2008 and June 2013. Consecutive, unselected, consenting candidates for LC were enrolled following standard ethics, informed consent, anesthesia, and clinical pathway protocol. They were allocated to control group (LC with ED) or study group (LC with CD, as per our published technique with the option for rescue ED). The study points were based upon Clavien-Dindo grading of postoperative complications. They were either, peri-operative events potentially affecting, hospital stay (Grade I) or Grade II-V, e.g., peri-operative hemodynamic instability, needing intervention/blood transfusion, injury to biliary ducts/hollow viscous, postoperative biliary leak, postoperative re-intervention, re-hospitalization, mortality, and any adverse event during a 90-day follow-up period. The data were prospectively collected in an integrated 'hospital information system' that could be retrieved only by independent external coordinators. Results: Demographics, co-morbidities, and gallbladder inflammation profile of the control group ( n = 361) and study group ( n = 384) were comparable. There was no rescue ED usage in the study group. Hospital stay (Grade I adverse outcome dependent) was longer, i.e., 1.6 ± 1.03 in the control versus 1.35 ± 1.2 days in the study group ( p < 0.001). Grade II-IV complications were significantly more ( p < 0.009) in control group. There was one common bile duct (CBD) injury in each group. The index bilio-enteric anastomosis for CBD injury in control group failed and needed a revision with multiple interventions. There was one grade V adverse outcome, i.e., mortality in the control group. Conclusion: Avoiding the use of ED in LC is associated with better outcomes. [ABSTRACT FROM AUTHOR]

Constrictive pericarditis secondary to endocardial pacemaker inflammation, without associated pericardial effusion or infection, has yet to be described in the literature. We present a case of a 42-year-old man who developed recurrent ascites from regional constrictive pericarditis following pacemaker implant. Symptoms resolved after pericardiectomy. [ABSTRACT FROM AUTHOR]

The author discusses the emergence of modern surgeons as leaders in the adoption of technology. Topics covered include India's transition with a fast-growing economy driven by consumerism, the use of digital means of payment such as Mobile wallets and FreeCharge, and the effort of a modern surgeon to evolve fast-track protocols to reduce the side effects of surgery.