Interferon in cerebrospinal fluid

Summary Interferon (IFN) was measured in serum and cerebrospinal fluid (CSF) of dogs after experimental (intranasal) infection with different strains of virulent canine distemper virus (CDV). Viral strains employed produce neurological changes in dogs that range from acute inflammatory to subacute, delayed demyelinating encephalomyelitis. With few exceptions, first appearance of serum-IFN correlated with the first elevated body temperature 4 days post-infection (p.i.). By 16 days p.i. IFN had disappeared from the serum of all infected dogs. In contrast, IFN was constantly detectable in CSF in dogs with CDV infection of the central nervous system (CNS). It was first detected 5 days p.i., was continuously detectable during the variable preclinical phase and into the period when signs of acute or delayed encephalomyelitis were evident. Dogs from which CDV would be retrieved from CNS tissue at necropsy always had CSF-IFN (up to 56 days p.i.). In contrast, dogs that recovered from infection, substantiated at necropsy by minimal, resolving CNS lesions and non-detectable virus, had IFN in CSF demonstrable for only a brief post-inoculation period. CSF-IFN appears to be a valid marker for CDV persistence in the canine CNS and may have broader applications.With 3 Figures     

Is fecundability associated with month of birth? An analysis of 19th and early 20th century family reconstitution data from The Netherlands

The relationship between fecundability and month of birth was investigated in a cohort of 1526 women who married between 1802 and 1929, using only women whose first marriage occurred before the age of 35 years. On the basis of their time to pregnancy (TTP, calculated as time between wedding and first birth minus gestational length), women were categorized into two groups: fecunds (TTP up to 12 months or prenuptial conceptions, n = 1348) and subfecunds (TTP >18 months, n = 118). By use of logistic regression, cosinor functions with a period of 1 year or 6 months and variable shift and amplitude were fitted through the monthly odds of subfecunds versus fecunds. The best fitting curve was unimodal, with a zenith in September (P = 0.13 for H0: no differences). Exclusion of childless women (n = 36, minimum follow-up 5 years) from the subfecunds led to a similar curve (P < 0.01), while childless women, as compared with fecunds, showed a birth distribution that was best represented with a bimodal curve with zeniths in January and July (P = 0.06). This study provides evidence for the existence of differences in fecundability by month of birth. The cause of this relationship is unclear, but may lie in a melatonin-dependent circannual variability of the quality of the oocyte.      

Signal detection theory and the psychophysics of pain: an introduction and review.

A brief explanation of signal detection theory is presented, followed by a review of the literature in which differences in pain report were analyzed to determine if changes were in sensitivity (physiological processes) or in response bias (a subject's willingness to report that a signal occurred). Three kinds of studies are reviewed: modification, procedural, and comparative and normative. The advantages of using a signal detection approach in pain research are emphasized. It is concluded that experimenters applying signal detection analysis to pain research should give greater consideration to methodological procedures and be cognizant of all possibilities for shifts in sensitivity (d)'.     

Epinephrine improves expiratory flow rates in patients with asthma who do not respond to inhaled metaproterenol sulfate

One hundred patients with acute asthma and peak expiratory flow rates (PEFR) less than 150 L/min were randomized and treated in a double-blind treatment protocol with either metaproterenol sulfate aerosol (MPA) inhalation and placebo injection or epinephrine injection (EPI) and inhaled placebo at entry and at 30 and 60 minutes, and then were treated with the crossover comparison regimen at 120, 150, and 180 minutes. The two groups had similar entry PEFRs and FEV1 (MPA, 112 L/min; 0.94 L, respectively; EPI, 111 L/min; 0.85 L, respectively) and similar plasma theophylline levels (MPA, 12.2 micrograms/ml; EPI, 13.8 micrograms/ml). PEFR and FEV1 were measured every 30 minutes for 4 hours. Mean expiratory flow rates among both groups were similar at entry and at 120 and 240 minutes. At 120 minutes, flow rates had improved in 28/46 MPA-treated patients (61%) and 48/54 EPI-treated patients (89%). Among these improved patients, flow rates were significantly higher in the MPA-treated group. At 120 minutes, 18/46 MPA-treated patients (39%) and 6/54 EPI-treated patients (11%) had PEFRs less than 120 L/min and PEFR and FEV1 less than 120% of baseline values (p less than 0.01). In 13 of these 18 MPA-treated patients who did not improve compared to 1/6 EPI-treated patients who did not improve, PEFRs were greater than 120 L/min, and PEFR and FEV1 had increased 20% or more above baseline values after treatment with the crossover comparison regimen (p less than 0.02).(ABSTRACT TRUNCATED AT 250 WORDS)     

Interstitial nephritis related to nonsteroidal anti-inflammatory agents and beta-lactam antibiotics: a comparative study of the interstitial infiltrates using monoclonal antibodies

Acute interstitial nephritis (AIN) is a common pattern of renal injury induced by therapeutic agents. In order to characterize the types of mononuclear leukocytes infiltrating the kidney in drug-induced interstitial nephritis, a panel of monoclonal antibodies (Leu1, Leu3a, OKT8, OKM1, Leu14, OKT17, IL-2) was applied to cryostat sections of 13 renal biopsies (five non-steroidal anti-inflammatory agents (NSAID) (Group I); five beta-lactam antibiotics (Group II), 3 miscellaneous (Group III]. The majority of infiltrating mononuclear leukocytes were Leu1-positive T cells (71.7 +/- 18.7%), followed by monocytes (15.2 +/- 7.7%) and B cells (7.4 +/- 9.1%). Leu3a/OKT8 ratio was 0.954 +/- 0.341. Rare cells reacted with antibody to the interleukin-2 receptor (1.4 +/- 1.2%). No statistically significant differences could be found in the percentages of T lymphocytes, B lymphocytes, monocytes, activated (IL-2+) T cells or Leu3a/OKT8 (helper/suppressor) ratios in the three groups. In Group II, the following pathologic correlations were seen: Leu3a/OKT8 versus interstitial inflammation (R = -0.848), percent Leu3a versus interstitial inflammation (R = -0.818), percent OKT17 versus tubulitis (R = 0.785), percent Leu14 versus tubular atrophy (R = -0.891), and interstitial edema (R = 0.965). Our findings support a role for cellular immune mechanisms in the pathogenesis of AIN related to both NSAIDs and beta-lactam antibiotics.     

Humoral immunity to canine distemper after immunization of dogs with inactivated and live measles virus

Summary Pairs of dogs were immunized with 2 injections of a) measles virus material containing hemagglutinin but no hemolysin [Tween 80 and ether (TE) treated] b) material containing both hemagglutinin and hemolysin (freeze-dried and heated at 95° C for 30 minutes), and c) live measles virus. Two unimmunized dogs were used as controls. All 8 dogs were challenged with virulent canine distemper virus (CDV). The two unimmunized dogs contracted a lethal infection, whereas immunized animals only showed mild signs of infection. Preimmunization with TE treated antigen gave the weakest protection. The animals displayed fever between day 4 and 10 after challenge. All titers of preexisting antibodies were boosted and antibodies against the measles hemolysin and CDV neutralizing antibodies increased from undetectable to moderate levels. Non-infectious intact virus (b) gave a more pronounced antibody response than TE antigen but antibodies against the hemolysin could not be detected. There was a good protection against disease (limited fever response). Replication of CDV caused a raise of antibody titers to levels normally seen only under conditions of hyperimmunization. Live measles virus stimulated the production of antibodies against both envelope components, but in spite of this virulent CDV could multiply and boost the titers of all antibodies.Abbreviations CDV canine distemper virus - TE Tween 80 and ether - SPF specific pathogen free - PHA phytohemagglutinin - HLI hemolysis inhibition - HI hemagglutination inhibition - NC-CF nucleocapsid complement fixation With 1 FigureThis work was supported by grants from the Swedish Medical Research Council (Project no. 16x–116) and by US Public Health Service grant 1 1201 NS 14342-01A1 from the National Institute of Neurological and Communicative Disorders and Stroke.     

Natural and immune cytolysis of canine distemper virus-infected target cells.

Natural and immune cytolysis of canine distemper virus (CDV)-infected target cells in vitro is described. Lymphocytes expressing natural cytotoxicity were found in specific-pathogen-free beagle dogs and in beagle-coonhound crosses before vaccination with CDV and indefinitely after vaccination, when the ephemeral immune lymphocyte-mediated cytotoxicity (ILMC) had declined. In contrast to the natural lymphocyte-mediated cytotoxicity, the ILMC was genetically restricted, could not be blocked by CDV-specific antibody, and was effective against measles virus-infected as well as CDV-infectd target cells. Lymphocyte populations were depleted of Fc receptor and surface immunoglobulin-bearing cells by rosetting techniques and tested in comparison. An antibody-dependent cell-mediated cytotoxicity was demostrated against CDV-infected target cells that were preincubated with CDV antibody when Fc receptor-bearing lymphocytes were not removed. The ILMC was measurable for approximately 10 days beginning at 6 days post-vaccination. In contrast, CDV antibody measured by virus neutralization and humoral cytotoxicity was detectable by 6 days postvaccination and persisted at peak levels for at least 5 months.     

Histopathological findings in rabbits after experimental acute exposure to the Loxosceles intermedia (brown spider) venom

Loxoscelism, the term used to describe envenomation with brown spiders, is characterized by a dermonecrotic lesion at the bite site. In the present investigation we submitted albino rabbits to an acute experimental envenomation protocol using Loxosceles intermedia (brown spider) venom, with in order to determine the pathogenesic features of the lesion induced by this spider, which is the cause of several accidents throughout the world. Rabbits received intradermal injections of the venom and were monitored over the first 4 h, and then at 12 h and 1, 2 and 5 days after envenomation. Histological specimens from 3 rabbits per time point were collected from euthanized animals and processed for histological examination by light microscopy. Major findings observed during the first 4 h were oedema, haemorrhage, degeneration of blood vessel walls, plasma exudation, thrombosis, neutrophil accumulation in and around blood vessels with an intensive diapedesis, a diffuse collection of inflammatory cells (polymorphonuclear leucocytes) in the dermis, and subcutaneous muscular oedema. Over the following hours and up to 5 days after envenomation the changes progressed to massive neutrophil infiltration (with no other leucocytes) into the dermis and even into subcutaneous muscle tissue, destruction of blood vessels, thrombosis, haemorrhage, myonecrosis, and coagulative necrosis on the 5th day.     

The effect of drugs on the acquisition of stimulus control in a conditioned suppression procedure

Rats were trained to press a lever under a variable-interval (VI) schedule of water reinforcement. After stable responding had developed, a 4.5-KHz tone (CS) was conditioned classically to a 2.5-mA electric shock (US) in groups of animals which had been given various psychoactive drugs or saline. Twenty-four hours later, a stimulus generalization test was conducted in the absence of drug; during this session, tones that varied in frequency around 4.5 KHz were presented while the animals were responding under the VI schedule. In animals conditioned under saline, all tones (non-differentially) suppressed responding which, however, recovered gradually over time. This suppressive effect was eliminated by lysergic acid diethylamide (LSD; 0.2 and 0.32 mg/kg), cocaine (20 mg/kg), diazepam (2.5 mg/kg), lisuride (0.08 mg/kg), mescaline (20 mg/kg) and 5-methoxy-N,N-dimethyltryptamine (4 mg/kg), and was attenuated by amphetamine (4 mg/kg), pentobarbital (15 mg/kg) and morphine (4 mg/kg). Atropine (10 mg/kg), scopolamine (1 mg/kg), clonazepam (0.5 mg/kg), and chlorpromazine (4 mg/kg) did not alter the suppressive effect of the tone. The serotonin antagonist BC-105 (6 mg/kg) reversed the effect of 0.2 mg/kg of LSD. These results suggest (1) that drug-induced stimuli may overshadow other (e.g., external) stimuli during classical conditioning and, (2) that drugs might affect behavior by altering processes (stimulus control or others) that do not simultaneously involve response or motor control.     

Course and anastomoses of the large hepatic veins to main structures on the liver surface

The upper liver veins of fifty adult people were dissected from their orifices up to their second ramifications. The courses of the hepatic veins to the main portal fissure and umbilical fissure were determined. Three large upper hepatic veins can be expected in 74%, an accessory one occurs in 26%. The three or four upper hepatic veins join V. cava inferior by two (66%) or three (34%) common terminal branches (length 0.9 cm). Mean diameters of right hepatic vein 1.5 cm, middle hepatic and left hepatic veins 1 cm, accessory upper hepatic vein 0.6 cm. The course of the middle hepatic vein to "cava-gallbladder-line" was determined. The most common vein of the umbilical fissure joins the left, occasionally the middle hepatic vein. The intrahepatic distribution of the liver veins was projected to the surface of the liver considering the typical resection lines. We recommend the following anatomical way of proceeding: right extended and left lateral lobectomy remain right to lig. falciforme hepatis; right lobectomy 1 cm right, left lobectomy 1 cm left to "cava-gallbladder-line".