Carcinoma of the ampulla of Vater in a haemophiliac patient

Malignancy in patients with haemophilia: a review of the literature

Haemophilia A and B are rare X-linked conditions. Elevated rates of HIV and hepatitis C related malignancies in these patients are well reported, however rates of other types of cancers are not. Therefore, a retrospective literature review of cancer in patients with haemophilia was conducted. A Medline search of articles from January 1966 to July 2009 utilizing the keywords haemophilia, leukaemia, malignancy, mortality, neoplasm and cancer was performed. The articles were reviewed and additional relevant publications were located from the references. Data on age, type and severity of haemophilia, HIV status, type of malignancy and outcomes were recorded as available. Thirty-two cases of leukaemia were identified as well as 159 malignant solid tumours. Specific incidence and prevalence rates could not be calculated due to the limited nature of the information available in the reports. Many types of malignancy have been reported in persons with haemophilia irrespective of infection with HIV and hepatitis C yet prevalence and incidence rates compared to the general population remain unknown. Patients with haemophilia can manifest non infectious related malignancies and symptomatic patients should be evaluated accordingly.

Ca2+ channel-blocking activity of propranolol and betaxolol in isolated bovine retinal microartery

The relaxant action of the standard beta-blocker propranolol was compared with betaxolol, a beta-blocker with established vasorelaxant properties. Ring segments of bovine retinal microartery (n=36, theta=237 microm), which lacks adrenergic nerves and beta-adrenoceptors, were mounted in an organ bath for isometric force recording. l-, d-, dl-Propranolol and betaxolol were equally effective in relaxing tonic K+-induced contractions. The median effective dose (ED50) value was approximately 10(-5) M for both beta-blockers. The relaxation by both beta-blockers was unaffected by endothelium removal. Like verapamil, both beta-blockers induced smaller relaxation of tonic prostaglandin F2alpha (PGF2alpha)-induced force, which depended less on Ca2+ influx than did K+-induced force: K+-, but not PGF2alpha-induced contractions were abolished in Ca2+-free medium. The minor betaxolol-induced relaxation of tonic PGF2alpha-induced force was blocked in Ca2+-free medium. With repeated exposures to PGF2alpha in Ca2+-free medium, initial phasic PGF2alpha-induced force declined less with every exposure than did subsequent tonic force. When the preparations were briefly equilibrated with K+- and Ca2+-rich solution before every exposure to PGF2alpha phasic force did not decline, indicating that phasic force primarily depended on Ca2+ released from intracellular stores. Both beta-blockers failed to relax phasic PGF2alpha-induced force. Thus propranolol and betaxolol are equipotent vasorelaxant drugs in retinal microartery, both probably acting via Ca2+ channel blockade. This activity (that shows no stereospecificity) thus appears to be a more general property of beta-blockers. Microarteries might be more sensitive to this activity than are conductance arteries.

Initial experience with a new long-acting beta-blocker, nadolol, in hypertensive patients

Nadolol, a new beta-blocker that is not metabolized and has a uniquely long pharmacological half-life (up to 24 hours) was employed as the sole drug therapy for thirty-one patients with mild to moderately severe essential hypertension. Twenty-two patients had a reduction over 3 months of 10% or more in supine diastolic pressure, including twelve who became normotensive. Daily dosage, administered in two divided doses, ranged up to 640 mg; however, twenty patients required 160 mg or less. Twenty-three patients continued therapy for a median additional period of 15 months, during which satisfactory control was maintained in seventeen patients. Side-effects of nadolol caused termination of therapy in only one patient.