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.     

Expression of the recombinant anchorless N-terminal domain of mouse hepatitis virus (MHV) receptor makes hamster of human cells susceptible to MHV infection

Mouse hepatitis virus (MHV) receptor, the receptor for the murine coronavirus MHV, was expressed in MHV-resistant hamster and human cells as a series of mutant, recombinant glycoproteins with carboxy-terminal deletions lacking the cytoplasmic tail, transmembrane domain, and various amounts of the immunoglobulin constant-region-like domains. The soluble receptor glycoproteins containing the N-terminal virus-binding domain were released into the supernatant medium and inactivated the infectivity of MHV-A59 virions in a concentration-dependent manner. Surprisingly, some of the anchorless glycoproteins were found on the plasma membranes of transfected cells by flow cytometry, and these cells were rendered susceptible to infection with three strains of MHV. Thus, in the cells in which the anchorless, recombinant receptor glycoprotein is synthesized, some of the protein is bound to an unidentified moiety on the plasma membrane, which allows it to serve as a functional virus receptor.     

A study of reversibly inactivated lipases for use in a morphine-triggered naltrexone delivery system

A key component of an implant that can be triggered by external morphine to release naltrexone is an inactivated enzyme that can be activated by morphine and which can then rapidly remove a protective coating surrounding a bioerodible polymer containing dispersed naltrexone. In this article we describe a lipase that has been conjugated with O3-carboxymethylmorphine, morphine-beta-3-glucuronide and O3-carboxypropylmorphine. The enzyme conjugate was then inactivated by complexation with affinity-purified goat polyclonal antimorphine antibodies. Antibody lipase interactions were measured by pH Stat and ELISA techniques. Affinity constants of the antibodies determined by radioimmunoassay using tritium-labeled morphine were 4.10 x 10(6), 3.18 x 10(6) and 3.38 x 10(7), respectively. While a concentration of 10(-5)M morphine was required to restore lipase activity, it is likely that a combination of correct morphine tether and correct affinity-purified antibody can increase sensitivity to the desired 10(-8)10(-9)M morphine level. Thus, a functioning device can almost certainly be constructed. However, it is unlikely that reactivation times of 1-2 h necessary for clinical usefulness in treatment of narcotic addiction can be achieved.     

Hydrodynamic basis for the choice of cavo-pulmonary anastomosis

Hyperlipidemia was identified in an 11-yr-old male cheetah (Acinonyx jubatus) and three related 3-yr-old male cheetah littermates. Hyperlipidemia in these four cheetahs was characterized by hypertriglyceridemia and hypercholesterolemia. The mean percentages of chylomicron and beta-lipoproteins were greater (P < 0.05) and the mean percent of alpha-lipoproteins was lower (P < 0.05) than the respective means for a group of 20 nonhyperlipidemic and clinically normal cheetahs. The etiology of the hyperlipidemia in these four cheetahs was not determined. However, the older cheetah also had chronic renal insufficiency and a parathyroid adenoma, conditions that have been associated with hyperlipidemia.     

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.     

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.