Absence of Mycobacterium avium ss paratuberculosis-specific IS900 sequence in intestinal biopsy tissues of Indian patients with Crohn’s disease

Background and Objective  

The role of Mycobacterium avium ss paratuberculosis (MAP) in the etiopathology of Crohn’s disease (CD) remains controversial, because of conflicting reports demonstrating the presence of MAP-specific insertion sequence from intestinal biopsy tissues of patients clinically diagnosed for the disease. The present study was carried out to investigate the presence of MAP DNA in the intestinal tissues of CD patients to ascertain the relevance of MAP in Indian patients with CD.     

Pulmonary valve preservation in Tetralogy of Fallot with a mildly hypoplastic annulus-should we do it?

Background  

The decision to preserve the pulmonary valve during intracardiac repair of Tetralogy of Fallot [TOF] is traditionally based on the intra-operative measurement of pulmonary annulus by a Hegar dilator as per Rowlatt’s table. We sought to evaluate if there can be flexibility in not using a transannular patch repair in Indian population with mildly hypoplastic pulmonary annulus.     

Potassium channel opening: a subtle two-step

Voltage-gated K⁺ channels undergo a voltage-dependent conductance change that plays a key role in modulating cellular excitability. While the Open state is captured in crystal structures of Kv1.2 and a chimeric Kv1.2/Kv2.1 channel, the Close state and the mechanism of this transition are still a subject of debate. Here, we propose a model based on mutagenesis combined with measurements of both ionic and gating currents which is consistent with the idea that the Open state is the default state, the energy of the electric field being used to keep the channel closed. Our model incorporates an 'Activated state' where the bulk of sensor movement is completed without channel opening. The model accounts for the well characterized electrophysiology of the 'V2' and 'ILT' mutations in Shaker, where sensor movement and channel opening occur over distinct voltage ranges. Moreover, the model proposes relatively small protein rearrangements in going from the Activated to the Open state, consistent with the rapid transitions observed in single channel records of Shaker type channels at zero millivolts.     

Cardiac MRI in the management of congenital heart disease in children, adolescents, and young adults

Recent advances in MRI have made this modality an important tool for evaluating heart disease. Faster scanning techniques, high spatial resolution, lack of ionizing radiation, lack of dependence on contrast material, and capability for functional imaging have made it an emerging noninvasive diagnostic tool with great potential in younger patients with heart disease. This article discusses the role of cardiac MRI, methods of evaluation, and newer application of MRI in evaluating congenital heart disease in pediatric and young adult patients.     

Effect of treatment on systolic time intervals in systemic arterial hypertension

Twenty-six hypertensive patients and 25 control subjects were studied, and their systolic time intervals (STI) were measured. It was found that an alteration in STI, signifying left ventricular dysfunction, sets in most of the hypertensives earlier than any evidence of left ventricular hypertrophy (LVH) by clinical, radiological or electrocardiographic criteria. The parameters affected are the PEP interval which shows prolongation and PEP/LVET ratio which is increased. After treatment, the left ventricular performance was found to improve in those who did not reveal evidence of LVH. Thus, STI may be a sensitive indicator of early left ventricular dysfunction in hypertensives and a useful guide to assess improvement after treatment at a stage when other non-invasive methods are not so useful.     

Tropical calcific pancreatitis: strong association with SPINK1 trypsin inhibitor mutations

BACKGROUND & AIMS: Tropical calcific pancreatitis (TCP) is a chronic pancreatitis unique to developing countries in tropical regions. The cause of TCP is obscure. Whereas environmental factors, such as protein energy malnutrition and ingestion of cassava, have been implicated, a genetic predisposition to the disease also may be important. In the present study we report on mutations in the serine protease inhibitor, Kazal type 1 (SPINK1) gene in north Indian patients with TCP. METHODS: We studied 66 unrelated TCP patients (44 men, 49 with diabetes, and 6 with family history of TCP), 25 relatives, and 92 healthy control subjects. Samples were analyzed for SPINK1 variants (-53C>T, L14P, N34S, P55S, and 272T>C) and cationic trypsinogen (PRSS1) variants (A16V, K23R, N29I, and R122H) by melting curve analysis. RESULTS: Twenty-nine patients (44%) carried the N34S missense mutation, of whom 9 (14%) were homozygotes. In contrast, only 2 (2.2%) control subjects were N34S heterozygotes (prevalence ratio 20.2; 95% confidence interval 5.0-81.8; P < 0.0001 vs. TCP). The severity of pancreatitis did not differ between TCP patients with or without N34S, or among those heterozygous or homozygous for N34S. Among TCP patients with or without diabetes, the frequency of N34S carriers (43% vs. 47%) and N34S homozygotes (14% vs. 12%) was similar. CONCLUSIONS: TCP is highly associated with the SPINK1 N34S mutation. The high prevalence of N34S in TCP patients with and without diabetes suggests that these 2 subtypes have a similar genetic predisposition. The genetic predisposition to TCP resembles, at least in part, the idiopathic chronic pancreatitis found in industrialized countries.     

Interruption of aortic arch in adults: surgical experience with extra-anatomic bypass

We reviewed our 3-year experience in treating interruption of the aorta in adult patients. Clinical profiles, surgical management, and results of early and mid-term follow-up are presented. From August 2001 through June 2003, 7 adult patients underwent an extra-anatomic bypass procedure to repair interruption of the aortic arch. Five patients underwent ventral aortic repair through a mid-sternotomy and an upper midline laparotomy, and 2 patients underwent repair through a left posterolateral thoracotomy. A bovine collagen-impregnated polyester fiber graft was used in 6 patients, and a Gore-Tex graft was interposed in 1 patient. All repairs were performed without cardiopulmonary bypass. Follow-up was complete in all patients. The mean follow-up was 1728 +/- 1 months (range, 9-31 months). No neurologic, renal, or gastrointestinal complications were noted in any patient. There was no in-hospital or late mortality or need for re-intervention. All patients were asymptomatic; however, 5 patients had mild residual hypertension. Graft patency in all the patients was confirmed by computed tomographic angiography. Interruption of the aorta is rare in adults. Ventral aortic repair through a midline approach is our preferred technique for surgical repair of this entity, because it avoids the extensive network of collateral vessels on the chest wall, enables simultaneous treatment of associated lesions, and in all likelihood reduces morbidity and mortality.