EEG delta power and auditory arousal in rested and sleep-deprived rabbits.

Slow-wave activity in the electroencephalogram is thought to reflect the depth or intensity of sleep. This hypothesis is primarily derived from studies of rats or humans. However, some characteristics of sleep of rabbits differ from those of rats or humans.

[Conservative treatment of fractures of the thoracolumbar spine.].

The authors present an overview on contemporary problems and possibilities of conservative treatment of fractures of the thoracolumbar spine. They draw attention to the theoretical basis of conservative treatment of fractures of the thoracolumbar spine elaborated in the twenties and thirties of this century. Based on their own experience they present a system of indications for reposition and fixation of these injuries.

Splenectomy and spleen autotransplantation due to splenic cyst.

Splenectomy is known to increase the risk of Overwhelming Postsplenectomy Infection (OPSI). Autotransplantation is one of the possibilities to preserve splenic functions. The authors performed spleen autotransplantations in two cases after the splenectomy of cystigerous spleens.

[Chemical tests with Marrubium species. Official data on Marubii herba in Pharmacopoeia Hungarica VII].

About 40 species of the Marrubium genus (Lamiaceae) are known of which 2 species (M. vulgare L. and M.

Strain differences in the somnogenic effects of interferon inducers in mice.

Increased slow-wave sleep accompanies influenza infection in C57BL/6 mice but not BALB/c mice. These strains of mice possess different alleles of the genetic lucus If-1, which codes for high (If-1h; C57BL/6) and low (If-1(1); BALB/c) production of interferon (IFN), a putative sleep-inducing cytokine. To evaluate the contribution of the If-1 gene to differences in murine sleep propensity, sleep patterns were evaluated in mice treated with the IFN inducers polyinosinic:polycytidilic acid (pIC) or Newcastle disease virus (NDV), with influenza virus, or with murine interferon (IFN-alpha) or IFN-alpha/beta.

Two distinct apolipoprotein B alleles in mice generated by a single 'in-out' targeting.

'In-out' gene targeting using a hypoxanthine phosphoribosyltransferase (HPRT) minigene was applied to generate two new alleles in the gene (Apob) coding for apolipoprotein B (apo B) in murine embryonic stem (ES) cells. Homologous integration of the targeting vector during the 'in step' disrupted the Apob gene leading to an allele encoding apo B81, having a 19% carboxyl-terminal truncation. All six targeted cells obtained had more than one insert at the locus, and the chromosomal target sequence in four of them was changed during the recombination.

Selective antibody reactivity with peptides from human endogenous retroviruses and nonviral poly(amino acids) in patients with systemic lupus erythematosus.

Objective: To investigate antibody responses to a broad panel of peptides derived from human endogenous retroviruses (HERVs) among unselected patients with systemic lupus erythematosus (SLE).

Methods: In sera obtained from 69 patients with SLE and healthy blood donors, immunoassay was used to measure levels of antibody against synthetic peptides derived from HERVs, exogenous retroviruses, and nonviral poly(amino acids).

Results: Measurement by immunoassay revealed increased frequencies of antiretroviral antibodies against 2 peptides derived from the env gene of the type C-like class, which includes ERV-9 and HERV-H, and against 2 peptides from the gag region of human T lymphotropic virus type I-related endogenous sequence 1, in patients with SLE.

Subthreshold facilitation and suppression in primary visual cortex revealed by intrinsic signal imaging.

Neurons in primary visual cortex (area 17) respond vigorously to oriented stimuli within their receptive fields; however, stimuli presented outside the suprathreshold receptive field can also influence their responses. Here we describe a fundamental feature of the spatial interaction between suprathreshold center and subthreshold surround. By optical imaging of intrinsic signals in area 17 in response to a stimulus border, we show that a given stimulus generates activity primarily in iso-orientation domains, which extend for several millimeters across the cortical surface in a manner consistent with the architecture of long-range horizontal connections in area 17.

Evaluation of anaesthetic regimens in guineapigs.

To establish reliable methods of chemical restraint and anaesthesia for mildly painful procedures in guineapigs, we compared the effects of the following anaesthetics and combinations of anaesthetics: tiletamine-zolazepam (two dosages), pentobarbital, methoxyflurane, ketamine-xylazine (three dosages), and ketamine-xylazine with methoxyflurane. Tiletamine-zolazepam induced a short period of chemical restraint but lacked analgesic effects at the doses tested. Although pentobarbital induced prolonged chemical restraint, the loss of responsiveness to painful stimuli was brief.

Transient decrease of acetylcholinesterase in ventral horn neurons caudal to a low thoracic spinal cord hemisection in the adult rat.

Light microscopic enzyme histochemistry was employed to study the alterations of acetylcholinesterase (AChE) within lumbosacral ventral horn neurons at survival times of 1, 4, 7, 14, 28, 60, and 90 days after low thoracic spinal cord hemisection in adult rats. The intensity of histochemical staining was quantified using densitometric techniques. Virtually all ventral horn neurons of sham-operated and unoperated animals, which served as controls, displayed intense AChE staining.

Lighting conditions alter Candida albicans-induced sleep responses in rabbits.

To evaluate the influence of light on sleep patterns after microbial challenge, we studied rabbits housed in 12:12-h light-dark (LD), constant light (LL), or constant darkness (DD) before and after intravenous Candida albicans inoculation. Compared with the LD group, uninoculated LL rabbits sporadically increased slow-wave sleep and delta-wave amplitudes during the circadian period previously associated with the dark phase. In contrast, uninfected DD rabbits showed reduced sleep during the circadian period previously associated with the light phase.

Immune-modulatory drugs alter Candida albicans-induced sleep patterns in rabbits.

To evaluate the influences of immune responsiveness on sleep alteration during infectious disease, sleep was monitored during Candida albicans infection in rabbits treated with immune-modulating drugs. Intravenous administration of C. albicans to normal rabbits initially increased and subsequently decreased both the amount of slow-wave sleep (SWS) and delta-wave amplitudes (DWA) during SWS.

B-50 (GAP-43) in the rat spinal cord caudal to hemisection: lack of intraspinal sprouting by dorsal root axons.

The controversial hypothesis that intraspinal sprouting by dorsal root axons promotes reinnervation of partially denervated neurons caudal to a low thoracic cord hemisection was re-investigated in rats using quantitative immunohistochemical analysis of the neural specific growth-associated protein B-50 (GAP-43) at postoperative survival times of 3, 10, 21, 42, and 90 days. The lack of increase in B-50-immunoreactivity in all segments below the hemisection at all survival times does not support the concept of intraspinal sprouting following the removal of supraspinal descending pathways.

Strain differences in sleep and other pathophysiological sequelae of influenza virus infection in naive and immunized mice.

To characterize behavioral and physiological alterations induced by viral respiratory infection, C57BL/6 and BALB/c strains of mice were monitored for 2 days before and 4 days after intranasal inoculation with influenza virus. Both strains developed hypothermia, decrease locomotor activity, and decreased delta-wave amplitude during sleep within 24 h after inoculation. However, infected C57BL/6 mice also spent more time in slow-wave sleep, but infected BALB/c mice did not.

Somnogenic effects of sleep deprivation and Escherichia coli inoculation in rabbits.

To evaluate the impact of sleep deprivation (SD) on microbially induced alterations in sleep, we used gentle handling to deprive rabbits of sleep for 4 h before or after intravenous inoculation with Escherichia coli (EC). Sleep was monitored for the next 20 h. EC inoculation alone increased slow-wave sleep (SWS) time, delta-wave amplitude (DWA) during sleep and SWS bout length during the initial 2-4 h after inoculation.

Structural changes of anterior horn neurons and their synaptic input caudal to a low thoracic spinal cord hemisection in the adult rat: a light and electron microscopic study.

Structural changes in lumbosacral ventral horn neurons and their synaptic input were studied at 3, 10, 21, 42, and 90 days following low thoracic cord hemisection in adult rats by light microscopic examination of synaptophysin immunoreactivity (SYN-IR) and by electron microscopy. There was an ipsilateral transient decrease in SYN-IR at the somal and proximal dendritic surfaces of anterior horn neurons which extended caudally from the site of injury over a postoperative (p.o.

Sleep, sleep deprivation and infectious disease: studies in animals.

Common perceptions that the desire for sleep is increased during mild infectious diseases like colds and 'the flu' have fostered beliefs that sleep promotes recovery from infectious disease and that lack of sleep increases susceptibility to infections. However, until recently, the relationship between infectious disease and vigilance received relatively little systematic study. At present, several model systems provide evidence that infectious disease is accompanied by alterations in sleep.

In vitro and in vivo motility studies of 99mTc HM-PAO labelled sperm cells.

The motility of 99mTc HM-PAO radiolabelled sperm cells, labelled as described previously (Balogh et al., 1992) was studied. The active migration of spermatozoa was demonstrated in capillary tubes containing bovine oestrous mucus, using an in vitro motility analyzer.

[Root canal treatment in Switzerland. The quantitative aspects--a determination of its status].

No recent data is available on the number of patients treated for root canal therapy in Switzerland. The aim of this study was to determine, by means of questionnaires, how many and which teeth were root canal treated in Switzerland by private practitioners. One questionnaire concerned the frequency of certain endodontic treatments performed during 10 consecutive working days.

[Materials and technics in root canal treatments in Switzerland--a determination of their status].

No data is available on either the materials nor techniques used by Swiss clinicians when doing root canal therapy (RCT). Consequently, in January 1993 questionnaires were posted to all dentists registered with the Swiss Dental Association, excluding those known not to practice RCT. Sixteen questions were answered detailing the disinfecting and obturating materials used, which types of files, preparation and obturation techniques were used and which radiographs were taken during RCT.

Comparison of acute phase responses induced in rabbits by lipopolysaccharide and double-stranded RNA.

Infection of injury results in several systemic and central reactions termed the acute phase response (APR). Substantial evidence suggests that cytokines induced by microbes initiate the APR. We compared the APR induced in rabbits by a model bacterial stimulus, lipopolysaccharide (LPS), to that induced by a model viral stimulus, polyriboinosinic:polyribocytidylic acid (poly I:C).

Orientation selectivity of cortical neurons during intracellular blockade of inhibition.

Neurons in the primary visual cortex of the cat are selectively activated by stimuli with particular orientations. This selectivity can be disrupted by the application of antagonists of the inhibitory neurotransmitter gamma-aminobutyric acid (GABA) to a local region of the cortex. In order to determine whether inhibitory inputs are necessary for a single cortical neuron to show orientation selectivity, GABA receptors were blocked intracellularly during whole cell recording.