Role of Stress Echocardiography in the functional assessment of prosthetic Mitral Valve.

Usually, the assessment of prosthetic valves by echocardiography is done at rest. For the patients with prosthetic valves, the echocardiogram taken at rest will not represent the true functional status of the valve. Patient`s day to day activities may induce symptoms. So in order to assess the functional status of the prosthetic valves, it is necessary that stress echocardiogram is done to mimic the daily activities of the patient. So it is assumed that the abnormalities observed under high flow conditions will not be seen at rest as the pressure gradients are related to flow. Resting studies of valve hemodynamics are found to be insufficient to diagnose valve dysfunction sometimes. Earlier, studies were done using cardiac catheterization with special emphasis on changes in prosthetic function observed with various types of physical stress like exercise or drug-induced stress. But these studies suffered from an inability to adequately stress catheterized patients .Moreover the procedures were cumbersome to the patient and also to the physician. With the advent of Doppler echocardiography, it was possible that studies could be done after significant exercise with increased ease and low risk. Using Doppler echocardiography, studies of exercise-induced changes in aortic and mitral prosthetic valve hemodynamics had started coming. AIM OF STUDY: 1. To study about the resting echo profile of patients with prosthetic mitral valve 2. To assess the function of the prosthetic valves by doing stress echocardiography by treadmill exercise and dobutamine infusion. CONCLUSION: 1. This Study helps in comparing the hemodynamic changes noted with stress induced by dobutamine and treadmill exercise.. 2. Normally functioning prosthetic valves in the mitral position can produce significant increases in valvular pressure gradients under conditions of high flow, and thus an estimation of diastolic cardiac flow must be measured before concluding that the valve dysfunction has occurred. 3. Dobutamine produces a greater augmentation in the effective mitral orifice area when compared to exercise. 4. Exercise protocol produces much higher increase in the pressure gradients when compared with dobutamine. 5. An abnormal increase in the pressure gradient without an increase in EOA signifies significant valve dysfunction and these patients should be monitored periodically for further deterioration and further action. Thus this study helps in finding dysfunction of prosthetic valves in the earlier stages itself

1-[2-(2,4-Dinitro­benzyl­ideneamino)phen­yl]-3-phenyl­thio­urea

In the title compound, C20H15N5O4S, the central benzene ring makes dihedral angles of 59.5 (1) and 51.7 (1)°, respectively, with the terminal phenyl and benzene rings. The mol­ecular structure exhibits weak intra­molecular N—H⋯N and C—H⋯S inter­actions. In the crystal structure, mol­ecules are linked by weak inter­molecular N—H⋯S and C—H⋯O inter­actions, forming a chain along [11]

Methyl 9-(4-bromo­phen­yl)-8a,9,9a,10,11,12,13,14a-octa­hydro-8H-benzo[f]chromeno[3,4-b]indolizine-8a-car­box­ylate

In the title compound, C27H26BrNO3, the mean plane of the naphthalene ring system makes a dihedral angle of 22.0 (1)° with the bromo-substituted benzene ring. The pyrrolidine and piperidine rings exhibit envelope and chair conformations, respectively. An inter­molecular C—H⋯Br inter­action is observed

(E)-4-Bromo-2-[(2,6-diisopropyl­phen­yl)imino­meth­yl]phenol

In the title compound, C19H22BrNO, the dihedral angle between the benzene rings is 76.17 (14)° and an intra­molecular O—H⋯N hydrogen bond with an S(6) graph-set motif is present. One methyl group is disordered over two sets of sites with site occupancies of 0.66 (3) and 0.34 (3). A weak inter­molecular C—H⋯π inter­action is observed in the crystal structure

N′-[(1E)-3-Bromo-5-chloro-2-hy­droxy­benzyl­idene]-4-tert-butyl­benzo­hydrazide ethanol monosolvate

In the title compound, C18H18BrClN2O2·C2H6O, the hy­droxy group forms an intra­molecular O—H⋯N hydrogen bond, which influences the conformation of the Shiff base mol­ecule, where the two aromatic rings form a dihedral angle of 21.67 (8)°. Inter­molecular N—H⋯O and O—H⋯O hydrogen bonds link two Shiff base mol­ecules and two solvent mol­ecules into a centrosymmetric heterotetra­mer. Weak inter­molecular C—H⋯O inter­actions link further tetra­mers related by translation along the a axis into chains

5-Methyl-12-phenyl­sulfonyl-12H-naphtho­[1,2-b]carbazole

In the title compound, C27H19NO2S, the naphtho­carbazole unit is approximately planar (r.m.s. deviation = 0.002 Å) except for the N atom, which is displaced by 0.122 (1) Å out of the mean plane. The dihedral angle between the naphtho­carbazole mean plane and the phenyl ring of the phenyl­sulfonyl substituent is 83.16 (3)°. An inter­molecular C—H⋯π inter­action involving the phenyl group and the pyrrole ring is observed in the crystal structure

6-Methyl-2,7-diphenyl-1,4-diazepan-5-one

The title compound, C18H20N2O, crystallizes with two mol­ecules in the asymmetric unit. The seven-membered ring in both mol­ecules adopts a distorted chair conformation. The dihedral angles between the phenyl rings are 43.2 (1) and 54.7 (1)° in the two mol­ecules. The crystal packing features N—H⋯O and weak N—H⋯π and C—H⋯π inter­actions

1-(Phenyl­sulfon­yl)benzo[1,2:2′,3′]thieno[5′,4′-b]carbazole

In the title compound, C24H15NO2S2, the ring system composed of the five fused rings is almost planar (r.m.s. deviation for all non-H atoms = 0.056 Å). The dihedral angle between the fused ring system and the phenyl ring is 83.4 (9)°. The crystal packing is stabilized by C—H⋯π and π–π inter­actions between parallel ring systems [centroid–centroid distances = 3.526 (3), 3.877 (3) and 3.712 (3) Å]

Method development and validation for acrylamide in potato cutlet by UHPLC-MS/MS

Surge in consumption of healthy and safe foods has challenged researchers to develop sensitive, precise, robust detection and quantification of food contaminants like acrylamide even if they are present in trace. Keeping this in view, a robust and sensitive analytical method was developed and validated for acrylamide quantification in a potato-based food product (potato cutlet), using LC-MSMS with positive electrospray ionization (+ESI). The method consists of adding acrylamide-d3 (deuterium labelled acrylamide) as an internal standard, extraction by modified QuEChERS method with d-SPE clean-up. Extracts were run on a reverse phase C-18 column for analysis by liquid chromatography. The limit of detection (LOD) and limit of quantification (LOQ) were determined as 0.7 and 2.0 μg kg− 1 , respectively, demonstrating the sensitivity of the method for trace detection. The developed method showed excellent results in terms of recoveries (91.0–109.16%), repeatability (RSD 1.8–10.60%), reproducibility (RSD 2.3–11.24%) and robustness (RSD 1.74–4.54%). The repeatability, reproducibility and robustness respectively, show the consistency, accuracy and stability of the developed method. The deviations in ion ratio and retention time were 17.25% and − 0.01 min, respectively. Compared to previous findings, the current study has achieved lower LOD and LOQ levels that reveals the higher sensitivity of this method for acrylamide quantification in potato cutletMinistry of Food Processing Industries, Government of India | Ref. Q-29/11/2018-R&DUniversidade de Vigo/CISU