Dipeptidyl peptidase IV expression in cancer and stromal cells of human esophageal squamous cell carcinomas,adenocarcinomas and squamous cell carcinoma cell lines

Dipeptidyl peptidase IV (DPPIV) is a transmembrane serine protease which is involved in the process of tumor invasion and development of metastases in human cancers. The aim of this study was to investigate the expression of DPPIV in cancer and stromal cells of both esophageal adenocarcinoma and squamous cell carcinoma (SCC). Tissue material from 159 patients was analyzed using immunohistochemistry. Western blotting was performed on cell lines and fresh frozen tissue sections. Results were compared with clinicopathological features. Evaluation of the immunohistochemical findings revealed significant differences between DPPIV expression in carcinoma cells and stromal cells, depending on the histological tumor type. A significantly higher level of DPPIV was found in adenocarcinomas compared to SCCs while no DPPIV was detected in normal esophageal epithelium. Overexpression of DPPIV in patients with adenocarcinoma was additionally associated with distant metastases. Thus, differences of DPPIV level in esophageal carcinomas compared with normal epithelium showed that esophageal malignancies were associated with an increased amount of cell surface‐bound DPPIV. Radiotherapy in patients had no impact on DPPIV expression in analyzed tissue samples. There was no correlation between DPPIV expression in cancer or stromal cells and survival of the patients.     

Prolonged Asymptomatic Torsade de Pointes

Torsade de pointer is often associated with syncope, particularly when prolonged. We report a cane of prolonged asymptomatic torsade de pointes in a 68-year-old woman being treated with quinidine gluconate for paroxysmal atrial fibrillation. Ambulatory monitoring obtained one week after an increase in the daily qninidine dosage demonstrated one minute of polymorphous ventricular tachycardia. The patient remained entirely asymptomatic throughout the time of the arrhythmia. Therefore, a lack of symptoms in patients at risk for torsade de pointes may not exclude the presence of this arrhythmia.     

Relationship Between Serum Potassium Concentration and Risk of Recurrent Ventricular Tachycardia or Ventricular Fibrillation

INTRODUCTION: Electrolyte abnormalities are considered a correctable cause of a life-threatening ventricular arrhythmia according to American Heart Association/American College of Cardiology Practice Guidelines, and ventricular tachycardia or ventricular fibrillation in the setting of an electrolyte abnormality is considered a class III indication for defibrillator implantation. However, there are little data to support this recommendation. The purpose of this study was to determine the risk of a recurrent sustained ventricular arrhythmia in patients with a low serum potassium concentration at the time of an initial episode of a sustained ventricular arrhythmia. METHODS AND RESULTS: One hundred sixty-nine consecutive patients who presented with a sustained ventricular arrhythmia and a serum potassium concentration determined on the day of the arrhythmia underwent defibrillator implantation. All patients had structural heart disease and left ventricular ejection fraction of 0.32+/-0.15. On the day of the index arrhythmia, 30% of the patients had a serum potassium concentration <3.5 or >5.0 mEq/L, including 7% who had a serum potassium concentration <3.0 or >6.0 mEq/L. For the entire cohort of patients, freedom from a recurrent sustained ventricular arrhythmia was 18% at 5 years and was not significantly different among patients with a serum potassium concentration <3.5 mEq/L (23%), between 3.5 and 5.0 mEq/L (16%), and >5.0 mEq/L (5%; P = 0.1). CONCLUSION: The results of the present study suggest that patients with structural heart disease and an abnormal serum potassium concentration at the time of an initial episode of sustained ventricular tachycardia or ventricular fibrillation are at high risk for a recurrent ventricular arrhythmia; therefore, implantable defibrillator therapy may be reasonable.     

Synthesis of specifically labeled peptides*

The unnatural labeled amino acid N-acetyl-D-3-(2-naphthyl)-[2,3-³H] alanine having a specific activity of 43.7 Ci/mmol was obtained in 98.7% optical yield by asymmetric reduction of 2-N-acetylamino-3-(2-naphthyl)acrylic acid with tritium gas in the presence of the chiral homogeneous catalyst (S,S)BPPM-Rh⁺. This amino acid was used in a microscale solution phase synthesis of the labeled LHRH antagonist [Ac-D-(2,3-³H) Nal¹, D-p-Cl-Phe², D-Trp³, D-hArg (Et₂)⁶, D-Ala¹⁰] LHRH. The chiral synthesis of labeled amino acids as a strategy for the general synthesis of labeled peptides is discussed.     

Some legal issues relating to passive smoking at the workplace

This paper will discuss some of the current legal issues concerning passive smoking at the workplace. Employers who introduce ‘No Smoking’ policies must take care in the manner in which they introduce any rules and the extent to which the new rules affect those employees who have always been permitted to smoke at work. Changing the rules in an arbitrary fashion may give rise to claims for breach of contract. Smokers may also sue for constructive dismissal should the new rules be imposed in an unreasonable manner. But employers who have followed a fair procedure may have the right to discipline or finally dismiss any smoker who refuses to accept the new rules.