A growth hormone pseudogene in the salmon genome

Representatives of the fish family Salmonidae were reported to possess two nonallelic growth hormone (GH)-encoding genes. In addition to those, we found a third GH-like sequence in a chum salmon genomic DNA library. A number of point mutations and large deletions abolished the possibility of expressing this sequence, showing that the chum salmon genomic DNA contains a GH pseudogene besides functional GH genes.     

Relative estimates of combination weights, decision criteria, and internal noise based on correlation coefficients

A means by which relative combination weights may be determined is described for a signal detection model in which the decision variable is a weighted linear combination of several independent, normally distributed random variables, Xi's. The first theorem presents the correlation between the binary response variables--signal versus no signal--and the component Xi. The second theorem presents a parallel result for the case that additive internal noise is present. Thus in psychophysical experiments, the relative combination weights may be obtained by correlating the observers' responses and the input random variables. Third, three numerical methods which allow the evaluation of the relative magnitude of the decision criterion and the variance of a hypothetical additive internal noise are considered.     

Fibrous skeleton endocarditis: repair using Konno procedure

Information about the surgical management of fibrous skeleton endocarditis is incomplete, as the vast majority of current literature describes the isolated repair of either the aortic or the mitral annulus, the combination rarely being addressed. Annular destruction, in the presence of endocarditis, demands extreme ingenuity for surgical treatment and cure. We describe and illustrate the Konno procedure for replacement of both infected mitral and aortic valves and repair of mycotic ventricular septal defects.     

The structure of Alu-like DNA nucleotide sequences in cyclostomes and fishes

By methods of DOT hybridization and polymerase chain reaction (PCR) structures similar to Alu repeats were shown in the genome of fish and lamprey. The fact of the presence of such sections in representatives of many orders of fishes, and also our experimental data allow to suppose that Alu-like structures, similar to 3' region of Alu repeats on mammals, have been already formed in these. The evolutionary significance of described structures has been supposed.     

The use of intermittent lighting in broiler raising. 2. Effects on the somatotrophic and thyroid axes and on plasma testosterone levels

Male and female broiler chicks were raised separately in nearly continuous lighting [23 h light (L):1 h dark (D), CL] and consumed feed ad libitum. At 7 d of age, the intermittent lighting schedule (1L:3D, IL) was imposed on half of the chicks, whereas the other chicks remained under CL. In addition to performance characteristics, several parameters of the somatotrophic and thyrotrophic axes were studied together with plasma concentrations of testosterone. Males had a higher growth rate than females regardless of the imposed lighting schedule and this pronounced growth difference is reflected by higher plasma concentrations of growth hormone (GH), and a better GH receptor occupancy. Differences in growth rate between sexes could not be attributed to differences in circulating 3,3',5-triiodothyronine (T3) levels or to hepatic deiodination activities. However, from 3 wk of age onwards, males had significantly higher plasma testosterone levels than females. Plasma GH and T3 levels decreased whereas plasma insulin-like growth factor-I and thyroxine levels increased with age in all experimental groups. The age-related decline in plasma GH levels were less pronounced for males than for females. No major changes in other hormonal parameters or deiodination activities could be observed as a result of imposing IL, except for the higher plasma GH levels of IL chickens, and for plasma testosterone concentrations in IL males at Day 41, which were twice the levels found in their CL counterparts. These results therefore suggest that the somatotrophic axis as well as circulating testosterone levels mediate the sex-related differences in growth rate and the compensatory growth as present in males.     

Patterns of viral replication correlate with outcome in simian immunodeficiency virus (SIV)-infected macaques: effect of prior immunization with a trivalent SIV vaccine in modified vaccinia virus Ankara

The dynamics of plasma viremia were explored in a group of 12 simian immunodeficiency virus (SIV)-infected rhesus macaques (Macaca mulatta) that had received prior immunization with either nonrecombinant or trivalent (gag-pol, env) SIV-recombinant vaccinia viruses. Three distinct patterns of viral replication observed during and following primary viremia accounted for significant differences in survival times. High-level primary plasma viremia with subsequently increasing viremia was associated with rapid progression to AIDS (n = 2). A high-level primary plasma virus load with a transient decline and subsequent progressive increase in viremia in the post-acute phase of infection was associated with progression to AIDS within a year (n = 6). Low levels of primary plasma viremia followed by sustained restriction of virus replication were associated with maintenance of normal lymphocyte subsets and intact lymphoid architecture (n = 4), reminiscent of the profile observed in human immunodeficiency virus type 1-infected long-term nonprogressors. Three of four macaques that showed this pattern had been immunized with an SIV recombinant derived from the attenuated vaccinia virus, modified vaccinia virus Ankara. These data link the dynamics and extent of virus replication to disease course and suggest that sustained suppression of virus promotes long-term, asymptomatic survival of SIV-infected macaques. These findings also suggest that vaccine modulation of host immunity may have profound beneficial effects on the subsequent disease course, even if sterilizing immunity is not achieved.     

Immunolabeling of Mu opioid receptors in the rat nucleus of the solitary tract: extrasynaptic plasmalemmal localization and association with Leu5-enkephalin

Activation of the mu opioid receptor (MOR) by morphine within the caudal nucleus of the solitary tract (NTS) is known to mediate both cardiorespiratory and gastrointestinal responses. Leu5-enkephalin (LE), a potential endogenous ligand for MOR, is also present within neurons in this region. To determine the cellular sites for the visceral effects of MOR ligands, including LE, we used immunogold-silver and immunoperoxidase methods for light and electron microscopic localization of antisera against MOR (carboxyl terminal domain) and LE in the caudal NTS of rat brain. Light microscopy of coronal sections through the NTS at the level of the area postrema showed MOR-like immunoreactivity (MOR-LI) and LE labeling in punctate processes located within the subpostremal, dorsomedial and medial subnuclei. Electron microscopy of sections through the medial NTS at this level showed gold-silver particles identifying MOR-LI prominently distributed to the cytoplasmic side of the plasma membranes of axons and terminals. MOR labeled terminals formed mostly symmetric (inhibitory-type) synapses but sometimes showed multiple asymmetric junctions, characteristic of excitatory visceral afferents. MOR-LI was also present along extrasynaptic plasma membranes of dendrites receiving afferent input from unlabeled and LE-labeled terminals. We conclude that MOR ligands, possibly including LE, can act at extrasynaptic MORs on the plasma membranes of axons and dendrites in the caudal NTS to modulate the presynaptic release and postsynaptic responses of neurons. These are likely to include local inhibitory neurons and both gastric and cardiorespiratory afferents known to terminate in the subnuclei with the most intense MOR-LI.     

Magnetic resonance imaging with implanted neurostimulators: an in vitro and in vivo study

OBJECTIVE: The goal was to assess the safety of magnetic resonance imaging (MRI) with implanted neurostimulators, in an in vitro and in vivo study. METHODS: Two different implantable pulse generators (IPGs) (ITREL II and 3; Medtronic, Minneapolis, MN) and different leads (separately and connected to an IPG) were tested in three different MRI scanners (0.2, 0.25, and 1.5 T). Measurements of the induced voltages (using an external oscilloscope) and the induced heat (using an infrared camera) were performed in an in vitro study. Finally, 38 patients with implanted neurostimulator systems (leads and IPGs) underwent MRI in 50 examinations, with continuous monitoring by a physician with uninterrupted visual and vocal contact with the patient. Twenty-five patients were studied prospectively, with documented printouts of the parameter settings before and after MRI. RESULTS: An induced voltage of 2.4 to 5.5 V was measured in the experimental configuration with a lead connected to an IPG. The voltage was higher with the leads alone, compared with the leads connected to the IPG, and was dependent on the MRI scanner, the sequences, and the type of lead. No heat induction was observed in any part of the hardware. No change of pulse shape or change of IPG parameters was observed during MRI. No adverse effects occurred in patients with chronically implanted deep brain leads connected to an IPG. CONCLUSION: MRI can be safely performed in patients with implanted neurostimulation systems with the tested deep brain leads connected to an IPG (ITREL II and 3), with running parameters. No heat induction was detected, and the experimentally measured induced voltage did not seem to harm the patients. Only the reed switch of the IPGs was activated; the other parameters remained unchanged. Further investigations must be performed to study the local electrical effects in larger plate electrodes; these effects might cause slight discomfort. There is no danger with any type of electrode during MRI examinations if the electrodes lie outside the region of interest. These observations are restricted to the tested devices. A conscientious estimation of the risks and benefits of MRI for patients with implanted devices is recommended. If the type of device is not known to the examiner, MRI should still be considered to be contraindicated.