Radioactivity in trinitite six decades later.

The first nuclear explosion test, named the Trinity test, was conducted on July 16, 1945 near Alamogordo, New Mexico. In the tremendous heat of the explosion, the radioactive debris fused with the local soil into a glassy material named Trinitite. Selected Trinitite samples from ground zero (GZ) of the test site were investigated in detail for radioactivity. The techniques used included alpha spectrometry, high-efficiency gamma-ray spectrometry, and low-background beta counting, following the radiochemistry for selected radionuclides. Specific activities were determined for fission products (90Sr, 137Cs), activation products (60Co, 133Ba, 152Eu, 154Eu, 238Pu, 241Pu), and the remnants of the nuclear fuel (239Pu, 240Pu). Additionally, specific activities of three natural radionuclides (40K, 232Th, 238U) and their progeny were measured. The determined specific activities of radionuclides and their relationships are interpreted in the context of the fission process, chemical behavior of the elements, as well as the nuclear explosion phenomenology.

Rapidly progressive fibrosing cholestatic hepatitis--hepatitis C virus in HIV coinfection.

Fibrosing cholestatic hepatitis (FCH) is a severe and progressive form of liver dysfunction seen in organ transplant recipients infected with hepatitis B virus or hepatitis C virus (HCV) and has been attributed to cytopathic liver injury. To date, no case of FCH due to HCV has been reported in HIV-positive individuals. We describe two cases of HCV-induced FCH in two patients coinfected with HIV, culminating in rapidly progressive liver failure and death. Histological features and progression in both cases were not consistent with drug effect or obstruction. Late institution of interferon-based therapy was ultimately unsuccessful. The HCV RNA was not markedly elevated in these cases, suggesting that the cytopathic effect of HCV in these patients was not simply a consequence of viral load. FCH may in part explain the accelerated development of cirrhosis previously observed among coinfected patients. Clinicians should remain vigilant for FCH in the HIV/HCV population and consider antiviral treatment in this setting.

The liver in heart failure.

Severe congestive heart failure is associated with two distinct forms of liver dysfunction: jaundice that is related to passive congestion and acute hepatocellular necrosis that is caused by impaired perfusion. Cardiac cirrhosis (fibrosis) may result from prolonged recurrent congestive heart failure. Ischemic hepatitis (shock liver) usually manifests as asymptomatic elevation of the serum aminotransferase levels after an episode of hypotension, although the clinical presentation may mimic that of acute viral hepatitis. In most cases, ischemic hepatitis is of little clinical consequence and is self-limited. Acute liver failure may occur in patients with preexisting cirrhosis, severe chronic heart failure, or sustained hepatic ischemia.