Toxicity assessment of carmine and its interaction with calf thymus DNA.

Carmine (CRM) is a colouring agent, extensively used in a variety of foods, beverages, cosmetics and pharmaceuticals. A battery of in vitro toxicity tests and chemical interaction studies of CRM with calf thymus DNA (ctDNA) have been conducted. Hemolysis assay clearly revealed the cytotoxic potential of CRM while Allium cepa and seed germination tests for phytotoxicity of CRM were also positive. DNA binding studies withplasmid nicking assay, clearly affirmed the genotoxic potential of CRM. The formation of CRM-ctDNA complex was suggested by UV-visible absorption and fluorescence spectra. The binding constant of CRM-ctDNA complex determined by ITC was found to be 1.72 x 106M-1. It also revealed the negative ΔH and ΔS values, indicating the role of hydrogen bonds and Van der Waals interactions in the formation of CRM-ctDNA complex. A remarkable (43.4%) displacement of Hoechst as compared to acridine orange (100%) suggests probable disruption of groove which might be possible due to the large size of CRM. Intercalatory mode of CRM binding was further confirmed by significant increase in double helix melting temperature of ctDNA and changes it's in circular dichroism spectra. Molecular docking also supported the notion that DNA binding involved both modes i.e. intercalatory as well as groove binding; moreover, it is consistent with the binding energies determined from ITC. In a nutshell, CRM is significantly cytotoxic to human and plant systems with its remarkable genotoxic potential too, wherein it targets DNA as a partial intercalator and ultimately break its backbone.Communicated by Ramaswamy H. Sarma.

Three-dimensional echocardiography assessment of carcinoid valvular heart disease: Images of each and all.

A 54-year-old male was found to have neuroendocrine carcinoma with hepatic metastasis. Two-dimensional (2D) transthoracic echocardiography (TTE) demonstrated dilated right ventricle and right atrium, and severe tricuspid and pulmonary regurgitation. Three-dimensional (3D) TTE en-face views showed thickened, retracted, and fixed tricuspid valve and pulmonic valve which remained widely open throughout the cardiac cycle. 3D TTE, particularly en-face views, demonstrates incremental value over 2D TTE by providing precise valvular anatomic details comparable to surgical findings. 3D TTE also offers a unique opportunity to assess all four valves simultaneously with en-face views to delineate their relationships with surrounding structures.

High-definition blood flow imaging in the assessment of left ventricular function: Initial experience and comparison with contrast echocardiography.

OBJECTIVES: The study aimed to assess the accuracy and reproducibility of the high-definition blood flow imaging (HD-Flow) in evaluation of left ventricular (LV) function by comparison with contrast echocardiography (Contrast). BACKGROUND: Contrast improves endocardial border visualization and assists in precise assessment of LV function. HD-Flow, a novel ultrasound technique that enhances blood flow discrimination in LV, could possibly be used for improving endocardial border definition without contrast. METHODS: Eighty patients with technically limited transthoracic echocardiograms had HD-Flow, and contrast performed sequentially. LV endocardial visualization, image acquisition time, wall motion, volumes, ejection fraction (EF), stroke volume (SV), and stroke volume index (SVI) were compared. Inter- and intra-observer agreements were examined in a randomly selected subgroup. RESULTS: Both HD-Flow and contrast significantly improved the percentage of the well-defined endocardial border segments (71% at baseline vs 94.1% by HD-Flow vs 94.9% by contrast, X2  = 401, P < 0.001). The acquisition time for HD-Flow was significantly less when compared to contrast (2.13 ± 1.18 minutes vs 10.96 ± 3.51 minutes, P < 0.001). LV end-diastolic volume (EDV), end-systolic volume (ESV), EF, SV, and SVI measured by the two methods correlated well (EDVr = 0.97, ESVr = 0.96, EFr = 0.90, SVr = 0.77, SVIr = 0.74, all P < 0.001). In comparison, HD-Flow was neither significantly different in detecting LV wall motion abnormality nor in EF, SV, and SVI measurements, but slightly underestimated LV volumes. CONCLUSIONS: HD-Flow imaging is feasible and user-friendly in enhancing LV endocardial definition. This technique is useful in both qualitative and quantitative assessment of LV function.

Echocardiographic assessment of the right ventricle in the current era: Application in clinical practice.

The right ventricle has unique structural and functional characteristics. It is now well recognized that the so-called forgotten ventricle is a key player in cardiovascular physiology. Furthermore, there is accumulating evidence that demonstrates right ventricular dysfunction as an important marker of morbidity and mortality in several commonly encountered clinical situations such as heart failure, pulmonary hypertension, pulmonary embolism, right ventricular myocardial infarction, and adult congenital heart disease. In contrast to the left ventricle, echocardiographic assessment of right ventricular function is more challenging as volume estimations are not possible without the use of three-dimensional (3D) echocardiography. Guidelines on chamber quantification provide a standardized approach to assessment of the right ventricle. The technique and limitations of each of the parameters for RV size and function need to be fully understood. In this era of multimodality imaging, echocardiography continues to remain a useful tool for the initial assessment and follow-up of patients with right heart pathology. Several novel approaches such as 3D and strain imaging of the right ventricle have expanded the usefulness of this indispensable modality.

Evolving new concepts in the assessment of aortic stenosis.

Echocardiography has been pivotal in evaluating aortic stenosis (AS) over the past several decades. Recent experience has shown a wide spectrum in the clinical presentation of AS. A better understanding of the underlying hemodynamic principles has resulted in emergence of new subtypes of AS. New treatment modalities have also been introduced, requiring precise evaluation of aortic valve (AV) pathology for implementation of these therapies. This review will discuss new concepts and indices in the use of echocardiography in patients with AS. Specifically, we will address the hemodynamic characteristics, clinical presentation, and management of normal-flow, high-gradient; paradoxical low-flow, low-gradient; and classical low-flow, low-gradient aortic stenoses.

Incremental value of transthoracic real time three-dimensional echocardiography in assessment of a right ventricular mass.

A 52-year-old male with a right ventricular mass that filled the entire right ventricle and assumed its shape was evaluated by two-dimensional and real time three-dimensional (3D) echocardiography. Contrast enhanced 3D imaging and quantitative assessments of the size of the mass were performed. The clinical correlation, the imaging characteristics of the mass, and the pattern of vascularity were consistent with metastatic hepatocellular carcinoma. The case illustrates the incremental role of 3D echo in defining the size, shape, spatial relationship, attachments, consistency, and vascularity of the right ventricular mass.

Real time three-dimensional echocardiography in assessment of left ventricular dyssynchrony and cardiac resynchronization therapy.

Left ventricular (LV) mechanical dyssynchrony is an important prognostic marker for higher morbidity and mortality in patients with symptomatic heart failure. However, the response rate to resynchronization varies among patients meeting current guidelines for Cardiac resynchronization therapy (CRT). Two-dimensional echocardiography and Doppler-based techniques have shown variable results in the assessment of LV dyssynchrony. There is an obvious need for a noninvasive tool that can reliably measure LV dyssynchrony. Accurate prediction of response to CRT will improve patient selection for such therapy. Real time three-dimensional echocardiography (RT3DE) is a novel noninvasive imaging modality that has been recently used in quantitative evaluation of global and regional LV function. A number of published studies have described the use of RT3DE in the measurement of LV dyssynchrony in patients with normal or reduced LV function. The systolic dyssynchrony index derived from RT3DE has been used to quantify LV dysynchrony and to evaluate and predict the response to CRT. This review will discuss the recently published data regarding the role of RT3DE in CRT.

Assessment of cytotoxic and genotoxic potential of refinery waste effluent using plant, animal and bacterial systems.

The work described here presents the toxic effect of Mathura refinery wastewater (MRWW) in plant (Allium cepa), bacterial (E. coli K12) and human (blood) system. The samples were collected from adjoining area of Mathura refinery, Dist. Mathura, U.P. (India). Chromosomal aberration test and micronucleus assay in (A. cepa) system, E. coli K12 survival assay as well as hemolysis assay in human blood were employed to assess the toxicity of MRWW. MRWW exposure resulted in the formation of micronuclei and bridges in chromosomes of A. cepa cells. A significant decline occurred in survival of DNA repair defective mutants of E. coli K12 exposed to MRWW. On incubation with MRWW, calf thymus DNA-EtBr fluorescence intensity decreased and percent hemolysis of human blood cells increased. An induction in the MDA levels of MRWW treated A. cepa roots indicated lipid peroxidation also. Collectively, the results demonstrate a significant genotoxic and cytotoxic potential of MRWW.

Assessment of left atrial appendage by live three-dimensional echocardiography: early experience and comparison with transesophageal echocardiography.

BACKGROUND: Live Three-Dimensional Echocardiography (L3D, Sonos 7500, Philips) has the potential to visualize all cardiac structures including left atrial appendage (LAA). We tested the feasibility of evaluating LAA by L3D and compared the findings to transthoracic echocardiography (2D) and in a subset of patients with transesophageal echocardiography (TEE). METHODS: L3D images were obtained in 204 consecutive patients referred for routine 2D or TEE. We performed wide-angled acquisitions from parasternal and apical views. TomTec system (4D Cardio-view, RT 1.2) was used to visualize LAA from multiple vantage points. RESULTS: LAA was adequately visualized by L3D in 139 of 204 (68.1%) patients. L3D visualization was dependent on image quality, suboptimal in 100 and diagnostic in 104 patients. Overall, LAA was visualized in 93 (45.5%) patients by 2D compared to 139 (68.1%) by L3D (P < 0.0001). In 100 patients with suboptimal image quality by L3D, LAA visualization was 16% by 2D and 35% by L3D, whereas in 104 patients with diagnostic images, LAA was visualized in 77 (74%) by 2D and in all 104 (100%) patients by L3D (P < 0.0001). In 37 patients referred for transesophageal echocardiography (TEE), live three-dimensional echocardiography (L3D) visualized left atrial appendage (LAA) in 34 patients with diagnostic image quality. Eight patients with LAA thrombi on TEE had thrombi detected by L3D as well. All patients with LAA thrombus had enlarged LA by both 2D and TEE. CONCLUSIONS: L3D is a promising technique in evaluation of LAA with and without thrombi. In patients with good quality transthoracic images L3D may be used as a screening tool in assessment of LAA.

Color M-mode flow propagation velocity and conventional doppler indices in the assessment of diastolic left ventricular function during isometric exercise.

BACKGROUND AND OBJECTIVE: Color M-mode flow propagation velocity (Vp) was shown to be a preload-independent measure of diastolic function. To study the effects of an increase in afterload induced by isometric handgrip exercise on diastolic function assessment in patients with cardiomyopathy, we measured Vp and conventional Doppler indices at baseline and at 30% of predetermined maximum handgrip strength. METHODS: Twenty-four patients with systolic dysfunction were divided into two groups: Group I comprising 12 patients with E/A < 1 (early filling velocity/atrial contraction velocity) and Group II comprising 12 patients with E/A > 1. All the patients underwent measurement of Vp, E velocity, its deceleration time (DT), A velocity, isovolumic relaxation time (IVRT), and pulmonary atrial flow reversal velocity (PFR) at baseline and at 30% of predetermined maximum handgrip strength. Twelve healthy controls underwent these same measurements. RESULTS: When comparing baseline to peak echocardiographic data, no significant changes were noted in Vp in any of the groups while a shift of pulsed Doppler indices of Group I toward a pattern closer to that of Group II was noted and a decrease in E velocity and E/A ratio with an increase in IVRT occurred in healthy controls. CONCLUSIONS: Color M-mode flow propagation velocity seems to be an afterload-independent measure of diastolic function in patients with moderate to severe cardiomyopathy while pulsed Doppler indices are more sensitive to loading conditions induced by isometric exercise.

Crimean-Congo hemorrhagic fever outbreak in Rawalpindi, Pakistan, February 2002: contact tracing and risk assessment.

A 25-year-old woman, later identified as index case of Crimean-Congo hemorrhagic fever (CCHF), presented to Holy Family Hospital in Rawalpindi, Pakistan with fever and generalized coagulopathy. A retrospective contact tracing was conducted to explore the modes of exposure possibly associated with transmission of CCHF infection among contacts. We traced 32 contacts of the index case and 158 contacts of secondary cases and tested them for IgG and IgM antibodies against CCHF virus by an enzyme-linked immunosorbent assay technique. According to the type of exposure, contacts were divided into five subsets: percutaneous contact with blood, blood contact to unbroken skin, cutaneous contact to non-sanguineous body fluids, physical contact with patients without body fluids contact, and close proximity without touching. Two out of four contacts who reported percutaneous exposure tested positive for antibodies to CCHF virus. We conclude that simple barrier methods and care in provision of CCHF cases may prevent transmission of this infection.

Color M-mode flow propagation velocity versus conventional Doppler indices in the assessment of diastolic left ventricular function in patients on chronic hemodialysis.

BACKGROUND AND OBJECTIVE: Color M-mode flow propagation velocity (Vp) has been reported as a preload-independent measure of diastolic function. To study the effects of loading conditions on diastolic function assessment in patients on chronic hemodialysis, we measured Vp and conventional Doppler indices pre- and posthemodialysis. METHODS: Twenty hemodialysis patients with normal systolic function underwent measurement of Vp, early filling velocity (E), its deceleration time (DT), atrial contraction velocity (A), isovolumic relaxation time (IVRT), and pulmonary atrial flow reversal velocity (PFR) pre- and posthemodialysis. Twelve healthy controls underwent these same measurements. RESULTS: Hemodialysis patients had significantly slower Vp at baseline than normal controls, while E/A, DT, IVRT, and pulmonary flow reversal were not significantly different. E, IVRT, and PFR were affected by hemodialysis, while color M-mode flow propagation velocities, A, and DT were not. CONCLUSION: Color M-mode flow propagation velocity seems to be a preload-independent measure of diastolic function in chronic hemodialysis patients in whom isolated diastolic dysfunction appears prevalent.