Diagnostic criteria for degenerative, inflammatory, proliferative nonneoplastic and neoplastic liver lesions in medaka (Oryzias latipes): consensus of a National Toxicology Program Pathology Working Group

Women residing in villages in three districts of Pakistan were recruited, trained to deliver primary care and mobilize their communities for health, assigned to limited catchment areas, provided with supervisory and managerial support, and remunerated. Their comprehensive activities substantially reduced infant, child and maternal mortality within a year and generated positive perceptions of family planning in the communities. The programme was cost-effective and appeared suitable as a model for reforming the organization and provision of health care services.     

Ultrasonography by emergency physicians in patients with suspected ureteral colic

We performed a prospective study of patients with suspected ureteral colic to evaluate the test characteristics of bedside renal ultrasonography (US) performed by emergency physicians (EPs) for detecting hydronephrosis, and to evaluate how US can be used to predict the likelihood of nephrolithiasis. Thirteen EPs performed US, recorded the presence of hydronephrosis, and made an assessment of the likelihood of nephrolithiasis. All patients underwent i.v. pyelography (IVP) or unenhanced helical computed tomography (CT). There were 126 patients in the study: 84 underwent IVP; 42 underwent helical CT. Test characteristics of bedside US for detecting hydronephrosis were: sensitivity 72%, specificity 73%, positive predictive value (PPV) 85%, negative predictive value (NPV) 54%, accuracy 72%. The PPV and NPV for the ability of the EP to predict nephrolithiasis after performing US were 86% and 75%, respectively. We conclude that bedside US performed by EPs may be used to detect hydronephrosis and help predict the presence of nephrolithiasis.     

Hereditary hemochromatosis

Genetic (hereditary) hemochromatosis is probably the most common autosomal recessive disorder found in white Americans, of whom about 5/1,000 (0.5 percent) are homozygous for the associated gene. The hemochromatosis gene is probably located close to the HLA-A locus on the short arm of chromosome 6. Homozygous individuals may develop severe and potentially lethal hemochromatosis, especially after age 39. Hereditary hemochromatosis involves an increased rate of iron absorption from the gut with subsequent progressive storage of iron in soft organs of the body. Excess iron storage eventually produces pituitary, pancreatic, cardiac, and liver dysfunction and death may result from cardiac arrhythmias, congestive heart failure, and/or hepatic failure or cancer. Early diagnosis can prevent these excess iron-induced problems. Iron overload owing to HLA-linked hereditary hemochromatosis can be distinguished from other causes of hemochromatosis by liver biopsies and interpretations. Patients at risk for genetic hemochromatosis should be screened, identified, and treated as early as age 20 to prevent or minimize the deadly complications of hemochromatosis. Population screening should include measurements of serum iron concentration, total iron binding capacity (TIBC), percent saturation of transferrin, and serum ferritin concentrations. Family members of hereditary hemochromatosis patients are at increased risk and should be tested. Screening, identification and early treatment (phlebotomies, sometimes in combination with the use of Desferal or other iron-chelating agents) may help prevent or reduce iron-related organ damage and premature deaths. Early diagnosis and treatment will reduce the population of aging individuals with severe, complicated hemochromatosis and dramatically reduce medical costs (billions of U.S. dollars per annum) associated with the management of this disease.     

Impact of anti-vaccine movements on pertussis control: the untold story

To assess the impact of anti-vaccine movements that targeted pertussis whole-cell vaccines, we compared pertussis incidence in countries where high coverage with diphtheria-tetanus-pertussis vaccines (DTP) was maintained (Hungary, the former East Germany, Poland, and the USA) with countries where immunisation was disrupted by anti-vaccine movements (Sweden, Japan, UK, The Russian Federation, Ireland, Italy, the former West Germany, and Australia). Pertussis incidence was 10 to 100 times lower in countries where high vaccine coverage was maintained than in countries where immunisation programs were compromised by anti-vaccine movements. Comparisons of neighbouring countries with high and low vaccine coverage further underscore the efficacy of these vaccines. Given the safety and cost-effectiveness of whole-cell pertussis vaccines, our study shows that, far from being obsolete, these vaccines continue to have an important role in global immunisation.     

Update on implantable cardioverter-defibrillators. New, safer devices have led to changes in indications

The safety and efficacy of ICDs have improved significantly in the past few years. Recent evidence supports the value of these devices not only for secondary prevention of sudden cardiac death, but also for primary prevention in post-myocardial infarction patients with poor left ventricular function, unsustained ventricular tachycardia, and inducible ventricular tachycardia on electrophysiologic study. Transvenous defibrillation using the defibrillator case as the high-voltage electrode and a biphasic shock is currently the procedure of choice. Implantation is simple, and the defibrillation thresholds are acceptably low. However, the possibility of interactions must be considered in patients with cardiac pacemakers.     

Pioneer Venus Sounder Probe Solar Flux Radiometer

The Solar Flux Radiometer aboard the Pioneer Venus Sounder Probe operated successfully during its descent through the atmosphere of Venus. The instrument measured atmospheric radiance over the spectral range from 400 to 1800 nm as a function of altitude. Elevation and azimuthal measurements on the radiation field were made with five optical channels. Twelve filtered Si and Ge photovoltaic detectors were maintained near 30°C with a phase-change material. The detector output currents were processed with logarithmic transimpedance converters and digitized with an 11-bit A/D converter. Atmosphetic sampling in both elevation and azimuth was done according to a Gaussian integration scheme. The serial output data averaged 20 b/s, included housekeeping (sync, spin period, sample timing and mode). The data were used to determine the deposition of solar energy in the atmosphere of Venus between 67 km and the surface along with upward and downward fluxes and radiances with an altitude resolution of several hundred meters. The results allow for more accurate modelling of the radiation balance of the atmosphere than previously possible.     

Can retrograde perfusion mitigate cerebral injury after particulate embolization? A study in a chronic porcine model

OBJECTIVE: We assessed the impact on histologic and behavioral outcome of an interval of retrograde cerebral perfusion after arterial embolization, comparing retrograde cerebral perfusion with and without inferior vena caval occlusion with continued antegrade perfusion. METHODS: Sixty Yorkshire pigs (27 to 30 kg) were randomly assigned to the following groups: antegrade cerebral perfusion control; antegrade cerebral perfusion after embolization; retrograde cerebral perfusion control; retrograde cerebral perfusion after embolization; retrograde cerebral perfusion with inferior vena cava occlusion, retrograde cerebral perfusion with inferior vena cava occlusion control, and retrograde cerebral perfusion with inferior vena cava occlusion after embolization. After cooling to 20 degrees C, a bolus of 200 mg of polystyrene microspheres 250 to 750 (microm diameter (or saline solution) was injected into the isolated aortic arch. After 5 minutes of antegrade cerebral perfusion, 25 minutes of antegrade cerebral perfusion, retrograde cerebral perfusion, or retrograde cerebral perfusion with inferior vena cava occlusion was instituted. After the operation, all animals underwent daily assessment of neurologic status until the time of death on day 7. RESULTS: Aortic arch return, cerebral vascular resistance, and oxygen extraction data during retrograde cerebral perfusion showed differences, suggesting that more effective flow occurs during retrograde cerebral perfusion with inferior vena cava occlusion, which also resulted in more pronounced fluid sequestration. Microsphere recovery from the brain revealed significantly fewer emboli after retrograde cerebral perfusion with inferior vena cava occlusion. Behavioral scores showed full recovery in all but one control animal (after retrograde cerebral perfusion with inferior vena cava occlusion) by day 7 but were considerably lower after embolization, with no significant differences between groups. The extent of histopathologic injury was not significantly different among embolized groups. Although no histopathologic lesions were present in either the antegrade cerebral perfusion control group or the retrograde cerebral perfusion control group, mild significant ischemic damage occurred after retrograde cerebral perfusion with inferior vena cava occlusion even in control animals. CONCLUSIONS: Although effective washout of particulate emboli from the brain can be achieved with retrograde cerebral perfusion with inferior vena cava occlusion, no advantage of retrograde cerebral perfusion with inferior vena cava occlusion after embolization is seen from behavioral scores, electroencephalographic recovery, or histopathologic examination; retrograde cerebral perfusion with inferior vena cava occlusion results in greater fluid sequestration and mild histopathologic injury even in control animals. Retrograde cerebral perfusion with inferior vena cava occlusion shows clear promise in the management of embolization, but further refinements must be sought to address its still worrisome potential for harm.     

Baseband emulators for the protocol testing of multimediacommunication networks

The testing of protocols for survivable computer communications networks that use different propagation media, so that the vulnerability of any one medium is offset by the availability of another, is considered. The design and construction of a prototype testbed that can emulate the effects of a stressed medium at either a packet or bit level is discussed, with particular reference to the Multi-Media Link Emulation currently under development. The design incorporates emulation-service protocols that fit in below the user packet switch network protocol and replace the actual user physical link layer and makes use of a seven-event fault set. The components of the ultimate system and its present implementation status are described