Pulmonary mass and multiple lung nodules mimicking a lung neoplasm as amiodarone-induced pulmonary toxicity

Amiodarone is an effective anti-arrhythmic agent. However, during long-term therapy, patients can develop severe adverse pulmonary reactions that are potentially life-threatening. A case of amiodarone-induced pulmonary toxicity is presented in a 78-year-old woman. She developed dyspnea and a pulmonary mass with associated multiple lung nodules mimicking a lung cancer following 5 years of treatment with amiodarone for atrial fibrillation. After drug withdrawal, and without any additional treatment, clinical and radiological improvement was observed, and radiological findings resolved completely within 6 months.     

Electrocardiographic prediction of the site of lesion in the anterior descending artery in acute myocardial infarction

INTRODUCTION AND OBJECTIVES: The goal of this study was to analyze the value of electrocardiography in predicting the site of the lesion in the left anterior descending coronary artery, in relation to the first septal and the first diagonal branches, in patients with acute anterior myocardial infarction. METHOD: Ninety consecutive patients who were admitted to the coronary unit with acute anterior myocardial infarction from July 1998 to May 2000 were studied retrospectively. The electrocardiographic changes were analyzed and correlated with the site of the lesion in the anterior descending artery, as determined by coronary angiography. RESULTS: The most useful parameters in predicting the site of the lesion in the left anterior descending coronary artery in acute anterior myocardial infarction are: 1) For lesions proximal to the first septal branch, ST-segment elevation in aVR (p < 0.001) and the absence of Q wave in V4-V6 (p = 0.01). 2) For lesions proximal to the first diagonal branch, abnormal Q wave in aVL (p = 0.01) and ST depression in III (p = 0.05). 3) For lesions proximal to both the first septal and first diagonal branches, ST elevation in aVR (p < 0.001), abnormal Q wave in aVL (p = 0.02), and absence of Q wave in V4-V6 (p = 0.01). 4) For lesions distal to both the first septal and first diagonal branches, abnormal Q wave in V4-V6 (p = 0.001) and absence of ST depression in III (p < 0.001). CONCLUSIONS: In acute anterior myocardial infarction, electrocardiography is useful for predicting the site of the lesion in the left anterior descending coronary artery in relation to the first septal and the first diagonal branches.     

Comparison of stent versus balloon angioplasty for pulmonary vein stenosis complicating pulmonary vein isolation

Introduction: Pulmonary vein stenosis (PVS) is a rare but significant complication of pulmonary vein isolation (PVI). Dilation and stent angioplasty have been described but not compared.
Methods and Results: All percutaneous interventions for PVS complicating PVI between December 2000 and March 2007 were reviewed. Acute success, defined as post-intervention stenosis ≤30%, and long-term outcome of dilation versus stent angioplasty were compared. Freedom from restenosis was defined as freedom from repeat intervention. Overall outcome for all interventions was examined. We studied 34 patients with 55 stenotic veins followed for a mean of 25 months. Dilation was performed in 39 veins and stenting in 40 veins (16 primarily, 24 after dilation restenosis). Acute success and restenosis rates were 42% and 72% for dilation versus 95% (P < 0.001) and 33% for stenting. Time to restenosis was greater for stent angioplasty (P = 0.003). Stents ≥10 mm in diameter had lower restenosis than smaller stents. Risk factors for restenosis included small reference vessel diameter and longer time from PVI to intervention for PVS. All but two patients experienced improvement (n = 10) or resolution of symptoms (n = 22). The mean percent stenosis decreased from 82% to 21% for the entire cohort and mean flow to the lung quadrant increased from 10% to 17%.
Conclusion: Stent angioplasty results in less restenosis than dilation, particularly for stents ≥10 mm. Early referral may improve long-term patency by minimizing reference vessel atrophy. Most patients with PVS post-PVI can be improved symptomatically with catheter intervention.     

Evolving concepts on regulation and function of renin in distal nephron

Sustained stimulation of the intrarenal/intratubular renin–angiotensin system in a setting of elevated arterial pressure elicits renal vasoconstriction, increased sodium reabsorption, proliferation, fibrosis, and eventual renal injury. Activation of luminal AT₁ receptors in proximal and distal nephron segments by local Ang II formation stimulates various transport systems. Augmented angiotensinogen (AGT) production by proximal tubule cells increases AGT secretion contributing to increased proximal Ang II levels and leading to spillover of AGT into the distal nephron segments, as reflected by increased urinary AGT excretion. The increased distal delivery of AGT provides substrate for renin, which is expressed in principal cells of the collecting tubule and collecting ducts, and is also stimulated by AT₁ receptor activation. Renin and prorenin are secreted into the tubular lumen and act on the AGT delivered from the proximal tubule to form more Ang I. The catalytic actions of renin and or prorenin may be enhanced by binding to prorenin receptors on the intercalated cells or soluble prorenin receptor secreted into the tubular fluid. There is also increased luminal angiotensin converting enzyme in collecting ducts facilitating Ang II formation leading to stimulation of sodium reabsorption via sodium channel and sodium/chloride co-transporter. Thus, increased collecting duct renin contributes to Ang II-dependent hypertension by augmenting distal nephron intratubular Ang II formation leading to sustained stimulation of sodium reabsorption and progression of hypertension.     

Low RKIP expression associates with poor prognosis in bladder cancer patients

Urothelial bladder cancer (UBC) is a heterogeneous type of disease. It is urgent to screen biomarkers of tumour aggressiveness in order to clarify the clinical behaviour and to personalize therapy in UBC patients. Raf kinase inhibitory protein (RKIP) is a metastasis suppressor, and its downregulation is associated with metastatic events in an increasing number of solid tumours. We evaluated the clinical and prognostic significance of RKIP expression in patients with high risk of progression UBC. Using immunohistochemistry, we determined RKIP expression levels in a series of 81 patients with high-grade pT1/pTis or muscle-invasive UBC. Staining of CD31 and D2-40 was used to assess blood and lymphatic vessels, in order to distinguish between blood and lymphatic vessel invasion (LVI). We found that 90 % of pT1/pTis tumours, 94 % of non-muscle invasive papillary tumours and 76 % of the cases without LVI occurrence expressed RKIP in >10 % of cells. In this group, we observed a subgroup of tumours (42 %) in which the tumour centre was significantly more intensely stained than the invasion front. This heterogeneous pattern was observed in 63 % of the cases with LVI. Low RKIP expression was associated with poorer 5-year disease-free and overall survival rates, and remained as an independent prognostic factor for disease-free survival. Loss of RKIP expression may be an important prognostic factor for patients with high risk of progression bladder cancer.     

Evaluation of the humoral immune response and cross reactivity against <Emphasis Type="Italic">Mycobacterium tuberculosis</Emphasis> of mice immunized with liposomes containing glycolipids of <Emphasis Type="Italic">Mycobacterium smegmatis</Emphasis>

Mycobacterium smegmati s (Ms) is a nonpathogenic mycobacteria of rapid growth, which shares many characteristics with Mycobacterium tuberculosis (MTB), the major causative agent of tuberculosis. MTB has several cell wall glycolipids in common with Ms, which play an important role in the pathogenesis of tuberculosis and the induction of a protective immune response against MTB infection in some animal models. In this study, the humoral immune response and cross reactivity against MTB, of liposomes containing a mixture of cell wall glycolipids of Ms and commercial lipids was evaluated, in order to study its possible use as a component of a vaccine candidate against tuberculosis. Liposomes containing total lipids extracted from Ms, distearoyl phosphatidyl choline and cholesterol were prepared by the dehydration-rehydration technique. Balb/c mice were immunized with the liposomes obtained and the antibody response and cross reactivity against MTB were tested by ELISA. Total lipids extract from Ms showed the presence of several polar glycolipids in common with MTB, such as phosphatidylinositol mannosides. Liposomes that contained glycolipids of Ms were capable of inducing a specific IgG antibody response that allowed the recognition of surface antigens of MTB. The results of this study demonstrated the presence of immunogenic glycolipids in Ms, which could be included to enhance the protective effects of subunit vaccine formulations against tuberculosis.