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81.
The need for a reliable bioanalytical method is of primary importance during preclinical studies. The aim of the present study was simultaneous determination of pioglitazone (CAS 111025-46-8) (PIO) and glimepiride (CAS 93479-97-1) (GLM) in plasma of rats. A high-performance liquid chromatographic method has been developed and validated using C18 column and UV detector. A mobile phase composed of acetonitrile and ammonium acetate buffer pH 4.5 in the ratio of 55:45%. The plasma samples clean-up was carried out using solid phase cartridges. The method was in the linear range of 50-8000 ng/mL for PIO and 50-2000 ng/mL for GLM. The coefficient of regression was found to be > or = 0.99. Precision and accuracy were within the acceptable limits, as indicated by relative standard deviation varying from 1.5 to 6.1% for PIO and 3.1 to 7.0% for GLM whereas the accuracy ranged from 97.0 to 106.4% for PIO and 96.5 to 106.4% for GLM. The mean extraction recovery was found to be 90.2 +/- 4.5, 76.8 +/- 2.8 and 85.2 +/- 5.2% for PIO, GLM and internal standard, respectively. Moreover, PIO and GLM were stable in plasma, up to 30 days of storage at -70 degrees C and after being subjected to bench top, auto-sampler, and three freeze-thaw cycles. The developed method was applied for preclinical pharmacokinetic studies.  相似文献   
82.
83.
Isolated single coronary artery without other congenital cardiac anomalies is very rare among the different variations of anomalous coronary patterns. The prognosis in patients with single coronary varies according to the anatomic distribution and associated coronary atherosclerosis. If the left main coronary artery travels between the aorta and pulmonary arteries, it may be a cause of sudden cardiac death. We present multimodality images of a single coronary artery, in which the whole coronary system originated by a single trunk from the right sinus of Valsalva with inter-arterial course of left main coronary artery. This rare type of single coronary artery was classified as RII-B type according to Lipton's scheme of classification. A significant flow-limiting lesions were found in the right coronary artery that was successfully treated with percutaneous coronary intervention.  相似文献   
84.
Background: Coronary artery anomalies are rare congenital abnormalities, most often found incidentally on conventional coronary angiography and CT angiography (CTA). CTA better delineates the origin and course of anomalous coronaries. Anomalous origin of coronary artery from the opposite aortic sinus of Valsalva (ACAOS) has a prevalence of 1% with a very few having an interarterial (malignant) course. There is limited literature, especially in the Indian population, dealing with this topic.Methods: In this retrospective observational study, angiographic data of 8500 consecutive patients from June 2011 to December 2019 at a large tertiary care hospital in western India was analyzed. Patients diagnosed with ACAOS underwent CTA for delineation of the exact anatomy. Those with a non-malignant course with evidence of ischemia clinically or on stress myocardial perfusion imaging (MPI), underwent PCI. Others with a non-malignant course were medically managed. Patients with malignant (interarterial) course were revascularized by coronary artery bypass graft (CABG) surgery in case of LCA involvement or positive MPI test. Asymptomatic patients with negative MPI were managed medically. Clinical follow-up over 12 months of patients undergoing PCI and those with a malignant course showed no major adverse cardiovascular events (MACE).Results: Of the 8500 patients studied, 74 (0.87%) had ACAOS. Of these, 51 (68.9%) patients had anomalous origin of right coronary artery (RCA) from the left aortic sinus, 21 (28.4%) had anomalous origin of the circumflex artery (Cx) from the right aortic sinus and two patients (2.7%) had an anomalous origin of the left main coronary artery (LCA) from the right aortic sinus. Interarterial course was found in five (6.7%) patients. Of these, four patients underwent CABG-one asymptomatic patient with LCA from right aortic sinus and three with positive MPI in anomalous RCA. All five patients with malignant course and ten patients who underwent PCI were free of MACE over 12 months’ clinical follow up.Conclusions: ACAOS is a rare anomaly and if interarterial course is excluded, then PCI is feasible in selected cases with significant stenosis. Patients with malignant course with inducible ischemia or LCA involvement should undergo surgical revascularisation.  相似文献   
85.
We previously demonstrated that refeeding after a prolonged fast activates a subset of neurons in the ventral parvocellular subdivision of the paraventricular nucleus (PVNv) as a result of increased melanocortin signaling. To determine whether these neurons contribute to satiety by projecting to the nucleus tractus solitarius (NTS), the retrogradely transported marker substance, cholera toxin-β (CTB), was injected into the dorsal vagal complex of rats that were subsequently fasted and refed for 2 h. By double-labeling immunohistochemistry, CTB accumulation was found in the cytoplasm of the majority of refeeding-activated c-Fos neurons in the ventral parvocellular subdivision of the hypothalamic paraventricular nucleus (PVNv). In addition, a large number of refeeding-activated c-Fos-expressing neurons were observed in the lateral parvocellular subdivision (PVNl) that also contained CTB and were innervated by axon terminals of proopiomelanocortin neurons. To visualize the location of neuronal activation within the NTS by melanocortin-activated PVN neurons, α-MSH was focally injected into the PVN, resulting in an increased number of c-Fos-containing neurons in the PVN and in the NTS, primarily in the medial and commissural parts. All refeeding-activated neurons in the PVNv and PVNl expressed the mRNA of the glutamatergic marker, type 2 vesicular glutamate transporter (VGLUT2), indicating their glutamatergic phenotype, but only rare neurons contained oxytocin. These data suggest that melanocortin-activated neurons in the PVNv and PVNl may contribute to refeeding-induced satiety through effects on the NTS and may alter the sensitivity of NTS neurons to vagal satiety inputs via glutamate excitation.  相似文献   
86.
4 months male child presented with failure to thrive. On general examination child had normal O2 saturation with characterstic elfin facies. Further evaluation of the patient showed major manifestations of Williams syndrome in form of supravalvar aortic stenosis, branched pulmonary artery stenosis along with cardiomyopathy. Although the entity is known, this article shows comprehensive diagnostic workup with the aid of multimodality imaging techniques. The genetic diagnosis of Williams syndrome was confirmed using fluroscent in situ hybridisation techniques (FISH). In this patient most of the manifestations of elastin vasculopathy were noted in the form of involvement of ascending aorta, pulmonary arteries and myocardium. We also want to emphasis the importance of echocardiography in newborn patients with dysmorphic facies as Williams syndrome can be easily missed in neonatal period.A 4 month old male child presented with symptoms of heart failure and poor weight gain. On examination, O2 saturation in both limbs was 99% and there was no significant blood pressure difference in all four limbs. He had a characterstic ‘elfin facies’ with a sunken nasal bridge, a long philtrum, wide mouth, prominent lower lip, small chin and low set ears (Fig. 1). 2D echocardiography showed situs solitus, concentric left ventricular hypertrophy with mild narrowing in the supravalvular region (Fig. 2) with systolic gradients of 26 mm Hg across the segment (Fig. 3) (Online Video 1). The right pulmonary artery (RPA) after its origin showed significant short segment stenosis with peak systolic gradients of 32 mmHg. The left pulmonary artery (LPA) after its origin showed mild narrowing (Figs. 4 and 5) (Online Video 2). Cardiac CT demonstrated supravalvular aortic stenosis (SVAS) with hour glass appearance of the aorta (Figs. 6 and 7) with bilateral pulmonary artery stenosis (PAS) involving RPA more than LPA (Figs. 8 and 9). Fluorescent in-situ hybridization (FISH) studies (Fig. 10) showed heterozygous deletion of elastin gene (Chromosome 7q11.23) and confirmed the diagnosis of Williams syndrome (WS).Open in a separate windowFig. 1Characterstic elfin facies.Open in a separate windowFig. 22D echocardiography showing mild narrowing in the supravalvular region.Open in a separate windowFig. 3Doppler showing gradients of 26 mm Hg across narrowed supravalvular region.Open in a separate windowFig. 42D echocardiography with color Doppler showing bilateral PAS.Open in a separate windowFig. 5Doppler investigation showing peak systolic gradients of 32 mmHg across the narrowed segment of RPA.Open in a separate windowFig. 6Cardiac CT with 3D reconstruction showing supravalvular aortic stenosis (SVAS).Open in a separate windowFig. 7Cardiac CT (Coronal section) showing SVAS.Open in a separate windowFig. 8Cardiac CT (Transverse section) showing bilateral PAS.Open in a separate windowFig. 9Cardiac CT with 3D reconstruction showing bilateral pulmonary artery stenosis (PAS) involving RPA more than LPA.Open in a separate windowFig. 10Fluorescent in-situ hybridization studies showing deletion of elastin gene (Chromosome 7q11.23).Supplementary data related to this article can be found online at http://dx.doi.org/10.1016/j.ihj.2015.02.026.The following are the Supplementary data related to this article:Video 1: Subcostal view showing turbulence in supravalvar region of aorta and the branched pulmonary arteries.Click here to view.(1.3M, mp4)Video 2: High parasternal view showing confluent pulmonary arteries with turbulence across the branched pulmonary arteries.Click here to view.(853K, mp4)WS is a genetic disorder occurring with a frequency of 1 in 20,000–50,000 live births. Manifestations of WS include congenital heart disease, hypertension, dysmorphic facial features, infantile hypercalcaemia and mental retardation. Apart from supravalvular AS and branched PA stenosis other cardiac abnormalities observed are bicuspid aortic valve, mitral valve regurgitation, coarctation of the aorta, ventricular or atrial septal defects. In neonates, cardiovascular symptoms were evident in 47% of WS children.1 PA stenosis often tends to regress spontaneously and SVAS tends to progress with time. In this patient most of the manifestations of elastin vasculopathy were noted in the form of involvement of ascending aorta and pulmonary arteries. The concentric left ventricular hypertrophy observed in our patient may be an expression of hypertrophic cardiomyopathy which is known to be associated with WS.1 In neonatal period all newborn patients with dysmorphic facies should be evaluated with echocardiography so that the cardiac abnormalities are not missed.  相似文献   
87.

Background

Balloon mitral valvotomy (BMV) is a well-established therapeutic modality for rheumatic mitral stenosis (RMS). However, there are chances of procedural failure and the more ominous post-procedural severe mitral regurgitation. There are only a few prospective studies, which have evaluated the pathogenic mechanisms for these major complications of BMV, especially in relation to the subvalvular apparatus (SVA) pathology.

Methods

All symptomatic patients of RMS suitable for BMV by echocardiographic criteria in a span of 1 year were selected. In addition to the standard echocardiographic assessment of RMS (Wilkins score and score by Padial et al.), a separate grading and scoring system was assigned to evaluate the severity of the SVA pathology. The SVA score was ‘I’, when none of the two SVAs had severe disease, ‘II’ when one of the two SVAs has severe disease, and ‘III’ when both SVAs had severe disease. With these scoring systems, the outcomes of BMV (successful procedure, failure, and post-procedural mitral regurgitation) were analyzed. Emergency valve replacement was performed depending on clinical situation, and in cases of replacement, the pathology of the excised mitral valves were compared with echocardiographic findings.

Results

Of the 356 BMVs performed in a year, 43 patients had adverse outcomes in the form of failed procedure (14 patients) and mitral regurgitation (29 patients). Forty-one among these had a SVA score of III. The sensitivity and specificity of the MR score was lesser than the SVA score (sensitivity 0.34 vs. 1.00, specificity 0.92 vs. 0.99, respectively). The mitral valvular morphology in 39 patients who underwent post-procedural valve replacements correlated well with echocardiography findings.

Conclusion

It is important to assess the degree of SVA pathology in the conventional echocardiographic assessment for RMS, as BMV would have adverse events when both SVAs were severely diseased.  相似文献   
88.
The goal of treatment of major depression should be full remission. Many patients, however, fail to achieve or maintain symptom-free status. Residual depressive symptoms are common, even where there has been a robust response to antidepressant therapy. In clinical studies, approximately one-third of patients achieve a full remission, one-third experience a response and one-third are nonresponders. Partial remission is characterized by the presence of poorly defined residual symptoms. These symptoms typically include depressed mood, psychic anxiety, sleep disturbance, fatigue and diminished interest or pleasure. It is currently unclear which factors predict partial remission. However, it is clear that residual symptoms are powerful predictors of relapse, with relapse rates 3-6 times higher in patients with residual symptoms than in those who experience full remission. Residual symptoms are also associated with more medical and psychiatric visits, increased public assistance, disability benefits, thoughts of and attempts at suicide and chronicity. The risk of stroke and coronary events is also higher in patients with residual depressive symptoms. The substantial proportion of patients who achieve only partial remission has traditionally been neglected in antidepressant trials. Given that residual symptoms may relate, in part, to an incompatibility between patient and treatment, further research is needed to predict a better match. These symptoms are a clinically relevant state of illness, and the correct choice of initial antidepressant treatment should offer the greatest chance of achieving full remission.  相似文献   
89.
We describe an unusual complication of the Inoue balloon technique, which has been treated successfully by application of a different technique. This technique has not been described elsewhere to the best of our knowledge.  相似文献   
90.
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