Deja vu: nosocomial hepatitis B virus transmission and fingerstick monitoring.

Purpose: Three patients with acute hepatitis B virus infection were identified who had been hospitalized on the same medical ward during a 19-day period several months earlier. An investigation was undertaken to determine if nosocomial transmission had occurred.

Subjects And Methods: A cohort study of patients admitted to the medical ward during the 19-day period in 1995 was conducted.

Dynamic properties of cardiovascular systems.

A recently derived mathematical model of an isolated heart is extended here to a closed-loop cardiovascular system. Taking the end-diastolic volume as state variable, the authors show that the closed-loop cardiovascular system can be described by a one-dimensional nonlinear discrete dynamical system that depends on parameters describing the systolic and diastolic properties of the heart, heart rate, total peripheral resistance, and arterial capacitance. Studies of this model show that the system possesses a rich spectrum of dynamical behavior, from stable points through stable cycles to a "chaotic" behavior.

Periodicities of cardiac mechanics.

Using a finite-difference equation to model cardiac mechanics, we simulated the stable action of the left ventricle. This model describes the left ventricular end-diastolic volume as a function of the previous end-diastolic volume and several physiological parameters describing the mechanical properties and hemodynamic loading conditions of the heart. Our theoretical simulations demonstrated that transitions (bifurcations) can occur between different modes of dynamic organization of the isolated working heart as parameters are changed.

Stability analysis of one-dimensional dynamical systems applied to an isolated beating heart.

In this paper we propose a new model of an isolated beating heart. The model is described by a one-dimensional non-linear discrete dynamical system which depends on several parameters. Applying stability analysis we investigate the dynamic properties of the non-linear system.

Prolapse of gastrostomy tube resulting in entero-enteric fistula and intussusception.

A case is reported in which a surgical gastrostomy tube migrated into the duodenum and eroded through the jejunal wall into an adjacent loop of jejunum. This resulted in an entero-enteric fistula, small bowel obstruction and intussusception. Since the number of gastrostomy tubes being placed endoscopically and surgically is increasing, gastroenterologists and surgeons should be alerted to these and other potential complications.

Marked elevation of transaminases and alkaline phosphatase during asymptomatic cholangitis associated with calcific pancreatitis-induced common bile duct stricture.

Cholestasis due to chronic pancreatitis has been well documented. Previous reports describe the gamut of biochemical, radiological and clinical findings in these patients. We wish to present the unusual association of a relatively asymptomatic cholangitis due to common bile duct (CBD) stricture induced by calcific pancreatitis.