Association of extrarenal Wilms'' tumor with a horseshoe kidney

Nephroblastoma (Wilms' tumor) is the most common renal malignancy in childhood. Extrarenal Wilms' tumor is uncommon, and the diagnosis is almost always postsurgical. The authors report two cases, located in the sigmoid mesocolon, one of these having an associated horseshoe kidney. Both were treated with excision followed by chemotherapy. They are now 36 months and 7 months postchemotherapy, respectively, and are symptom and recurrence free. Both had favorable histological findings. Association with a horseshoe kidney raises an important issue regarding the histogenesis of these tumors. The authors believe that there is a nexus between the fusion of metanephric blastema during the sixth to seventh week of intrauterine life and the "ectopic" metanephric blastema cells that may give rise to extrarenal Wilms' tumor. Association with a horseshoe kidney with an extrarenal Wilms' tumor has been reported on five previous occasions. The authors closely examine the link between the two.     

Infection complicating percutaneous liver biopsy in liver transplant recipients

There is controversy about the frequency of and risk factors for infectious complications of percutaneous liver biopsy in liver transplant recipients. The aim of this study was to identify the incidence and nature of complications associated with liver biopsy after orthotopic liver transplantation (OLT), with particular emphasis on infection. The medical records of all patients undergoing OLT between January 1990 and August 1994 were reviewed retrospectively to identify complications requiring hospitalization within one week of percutaneous liver biopsy. The nature and severity of complications were recorded and possible risk factors for infectious complications were examined. One hundred ninety-eight patients underwent 1,136 percutaneous liver biopsies. There were eleven complications (0.96%), including as follows: 7 infections, 3 bleeding episodes, and 1 vasovagal reaction. Infections after percutaneous liver biopsy included fever and bacteremia (n = 6), and fever without bacteremia (n = 1). All infections developed only in patients with underlying biliary tract abnormalities; the frequency of infection was higher (9.8%) in patients with choledochojejunostomy when compared with those with choledochocholedochostomy (1.4%). Bacteremia was more likely caused by skin flora in patients with choledochocholedochostomy (CDC) and by enteric bacteria in patients with choledochojejunostomy (CDJ). All infections were treated successfully with parenteral antibiotics. We conclude that biliary tract abnormalities are the primary risk factors for infection after percutaneous liver biopsy, although the risk is higher in patients with CDJ than with CDC. These data support the use of antibiotic prophylaxis before percutaneous liver biopsy in OLT recipients with biliary tract abnormalities.     

Public health surveillance for hereditary hemochromatosis

The recent realization that hemochromatosis is a common condition has created opportunities to develop unified public health surveillance for this disorder and its complications and to design programs to prevent unnecessary illness and death resulting from this disorder. Public health surveillance for hemochromatosis can be used to measure the magnitude of the problem (for example, to establish the number of persons with evidence of early iron overload); identify research needs; reveal the natural history of the disease; detect changes in health care practices, such as use of screening tests; and evaluate interventions, such as phlebotomy. Existing surveillance has been limited to periodic measurement of morbidity and mortality done by using hospital discharge records, health examination surveys, vital statistics, and data from small research registries. The improvement of surveillance will entail the ongoing collection of information from population-based surveys, such as the Behavioral Risk Factor Surveillance System; the collection of data on provider practices (for example, through the National Ambulatory Medical Care Survey); and the establishment of population-based registries. Creating population-based registries requires consensus on case definitions; strategies to encourage case ascertainment and reporting; policies and procedures for protecting privacy and ensuring confidentiality; and partnerships among providers, researchers, and public health officials. Longitudinal data from population-based registries will provide insight into determinants of disease expression, such as pattern or degree of iron overload. This information is critical for developing evidence-based recommendations for population screening, monitoring changes in medical practices, and assessing the effect of preventive measures.     

Essential design and fabrication considerations for the reliable performance of an electrothermal MEMS microgripper

Microsystem Technologies - Over the past years, microelectromechanical systems (MEMS) have become a vital component within a wide range of technologies, making the study of their performance and...     

Mouse hepatitis virus receptor activities of an MHVR/mph chimera and MHVR mutants lacking N-linked glycosylation of the N-terminal domain

Mouse hepatitis virus binds to the N-terminal domain of its receptor, MHVR, a murine biliary glycoprotein with four immunoglobulin-like domains (G.S. Dveksler, M. N. Pensiero, C. W. Dieffenbach, C. B. Cardellichio, A.A. Basile, P.E. Elia, and K. V. Holmes, Proc. Natl. Acad. Sci. USA 90:1716-1720, 1993). A recombinant protein with only the anchored N-terminal domain was not a functional receptor, but a recombinant protein with the N-terminal domain of MHVR linked to the second and third immunoglobulin-like domains and anchor from the mouse poliovirus receptor homolog, mph, was a functional receptor for mouse hepatitis virus. The native four-domain MHVR has 16 potential N-linked glycosylation sites, including three on the N-terminal domain. Recombinant proteins lacking each one of these three sites or all three of them were functional receptors. Thus, glycosylation of the N-terminal domain is not required, but a glycoprotein longer than the N-terminal domain is required for virus receptor activity.     

Segregation of optic axons based on central target: the medial optic tract in Rana pipiens

The electrophysiological integrity of the adult rat spinal cord was assessed at the lumbar, lower cervical and cortical levels after the animals sustained a severe contusion injury at the mid-thoracic level (T8) and received either carbon filament cultured with fetal spinal cord tissue implants, fetal tissue implants, or carbon filament implants alone. Somatosensory evoked potentials (SSEPs) and motor evoked potentials (MEPs) were recorded from all animal groups at the end of the 8-week survival period. The results of this study demonstrate that the spinal cord injured animals that received carbon filament cultured with fetal spinal cord tissue implants had the highest degree of electrophysiological recovery, indicating that this combination plays an important role in promoting recovery after injury.     

Preventive check-ups of pregnant women in Denmark. Common ailments in pregnancy

The study was conducted in order to describe the extent and content of advice on common ailments in pregnancy given by doctor or midwife during prenatal visits and to describe the frequency of ailments in the period before the visits. The design was a nationwide cross-sectional study based on questionnaires completed by pregnant women who had seen a general practitioner (GP), midwife or hospital doctor for prenatal care. Ailments and advice in connection with one specific visit were reported. The questionnaires were completed by 517 women after a prenatal visit to their GP (92% of eligible), by 514 women after a prenatal visit to the midwife (91% of eligible), and by 203 women after a prenatal visit to a doctor in the maternity department in pregnancy week 16-18 (84% of eligible). The results showed that nausea, pollakisuria, tiredness and heartburn had been present during the period before the visit in about half the women. Between a third and a fourth of the women had been discomforted by back pain, discharge or cramps. From 15 to 58 percent had been given advice, depending on the symptom. The advice was of many different kinds. To a large extent the women wanted to talk to the health professionals about the ailments, and most often they wanted to talk to a midwife about the ailments. We conclude that common ailments of pregnancy are frequent and they should be investigated more. Nearly all pregnant women want to talk about the subject during prenatal visits. The objectives of giving advice should be clearer, and clinical studies of the effectiveness of the advice are needed.