Gravity responses of Purkinje cells in the nodulus

Summary In cats, either decerebrated or under chloralose anaesthesia, Purkinje cells (P-cells) of the cerebellar nodulus have been examined with the animal under static lateral tilt (roll±20°). The cell activity was extracellularly recorded and both simple and complex spike discharge patterns were studied.In 20 cells out of a population of 198, simple spike firing was found to be affected by static roll. Ten cells had an -type response, 8 a -type, while only single examples of and activations were found.Out of 67 Purkinje cells tested for complex spike activation, 5 were found to be sensitive to static roll, 4 with an or response and one with a response.The results are to be attributed to pure otolith activation and show that this input is able to modulate P-cell activity in the nodulus through both the mossy fibre and the climbing fibre systems.     

Adaptation and habituation of the vestibulo-ocular reflex in intact and inferior olive-lesioned rats

Summary The gain of the vestibulo-ocular reflex (VOR) of intact pigmented rats was adaptively modified by training protocols that created a visual-vestibular conflict. For training, head restrained animals were oscillated on a turntable in front of an optokinetic pattern projected onto a cylindrical wall. The optokinetic pattern either moved the same amplitude with the animal (in-phase: 0.05 Hz ± 20°/s) or opposite in direction (out-of-phase: turntable and pattern 0.05 Hz ± 10°/s each). VOR responses were tested in darkness before and after each 8 min training period for a duration of 40 min. During out-of-phase training the gain of compensatory eye movements measured in light was close to 2 from the beginning on and the VOR tested in darkness increased in gain progressively from 0.48 (±0.12) to 0.9 (±0.3; P < 0.05) in 5 out of 7 rats. Two rats did not adapt their VOR gain. Phase values decreased slightly by about 10°. During in-phase stimulation compensatory eye movements were almost completely suppressed (gain close to 0) from the beginning on and the VOR tested in darkness decreased gradually in gain from 0.62 (±0.17) to 0.13 (±0.1; P<0.001) in all 6 trained rats. Phase values decreased in parallel from 151° to 119° (P< 0.01). The effectiveness of the in-phase training paradigm in the absence of compensatory eye movements indicates that retinal image slip is the relevant signal for adaptation. In seven rats with histologically verified almost complete inferior olive (IO) lesions (chemically induced at least 45 days prior to training), out-of-phase and in-phase stimulation evoked compensatory eye movements with gains comparable to those in intact rats. VOR parameters measured in darkness were altered with respect to those of control rats. Gain differed extremely between individuals and phase lag re acceleration was in all IO-lesioned rats larger than in intact rats. The time constant of the VOR in response to table velocity steps was significantly longer (17 s ±4) than in intact rats (11 s ± 3). Training did not alter the gain of the VOR in 5 out of 7 IO-lesioned rats. One rat increased its gain during out-of-phase training in the first, but not during a second training session (and not during in-phase training) and another rat decreased its gain during in-phase training (but not during out-of-phase training). These changes in VOR gain might have occurred by chance rather than by learning. The absence of adaptation in IO-lesioned rats can be explained either by the absence of climbing fiber mediated slip signals in the cerebellar cortex or by lesion-induced secondary changes which result in a long-term reduction of the inhibitory efficacy of Purkinje-cells. In the absence of arousing stimuli VOR responses of intact rats exhibit a strong decrement during table oscillations in darkness. Between trials, with the rat at rest, response magnitude recovered spontaneously. Six out of 8 IO-lesioned rats expressed a very similar modification of their VOR gain. These results indicate that the neural mechanisms responsible for adaptive gain decrease during in-phase training and those responsible for a gain decrease during short-term habituation are different.     

Comparative Characterization of Cytokine Production by Concanavalin A-Activated Splenocytes from BALB/c and C57Bl/6 Mice after Cold Exposure

The level of cytokines produced by ConA activated splenocytes was studied in male BALB/c and C57Bl/6 mice after single and repeated cold exposure (–20°C, 3 min). Single cold exposure significantly decreased IL-2, -3, -4, -5, -10, -12, IFN- production in BALB/c mice and decreased IL-2 content and increased TNF- level in C57Bl/6 mice. Repeated cold exposure normalized the content of IL-2, -4, -10, -12, and IFN- in BALB/c mice, which reflects the development of adaptive immune reactions. In C57Bl/6 mice IL-2, -3, -5, -10, -12, and IFN- production remained significantly decreased, which attested to dysadaptive processes.__________Translated from Byulleten Eksperimentalnoi Biologii i Meditsiny, Vol. 139, No. 2, pp. 188–190, February, 2005     

Otolith orientation and downbeat nystagmus in the normal cat

Upward drift of the eyes in darkness, influenced by whole body orientation, was studied in 12 cats using electromagnetic search coil and electro-oculographic techniques. Animals were positioned stationary with respect to gravity with 0° tilt (upright) or rolled 90° (on side), pitched 90° (on nose or on tail), or inverted 180° (upside down). A downbeat quick-phase nystagmus (slow-phase upward in the cat's orbit) was measured, varying in magnitude with angle of tilt (0.21°/s at 0° tilt; 4.14°/s at 180° tilt). The drift was not present in the light. Upward eye velocities over a range of body orientations in darkness suggest a systematic drive to the eyes which increases with tilt away from upright. The relationship of this behavior to previous models of angular velocity estimation by an otolith-driven central mechanism is discussed.     

Failure to demonstrate disruption of ultradian growth hormone rhythm and insulin secretion by dorsomedial hypothalamic nucleus lesions that cause reduced body weight,linear growth and food intake

Summary Weanling male rats received bilateral electrolytic lesions in the dorsomedial hypothalamic nuclei (DMNL rats); sham-operated animals served as controls. At the end of a 39-day postoperative period DMNL rats were lighter and shorter than controls and also exhibited significant hyopophagia. Their efficiency of food utilization (weight gained for the amount of food eaten) was normal, however. Subsequent determination of plasma growth hormone (GH) and insulin (IRI) levels every 15 min for 6-h periods from freely moving chronically cannulated rats showed no differences in pulsatile patterns and peaks of GH nor in plasma IRI levels between DMNL rats and controls. There was also no significant difference between mean 6-H GH and IRI concentrations between the two groups. The reduced body weight, length and food intake are apparently unrelated to the normal GH and IRI secretory patterns. In conjunction with previous data indicating normal somatomedin activity and normal responses to various homeostatic challenges, the data make a strong case for the argument that DMNL rats are not growth-retarded. Rather, they are normal animals that are scaled-down to a smaller size with maintenance of normal homeostatic capacity. This has been hypothesized to be due to the existence in these animals of an organismic set point.     

Isolation and characterization of Chlamydomonas temperature-sensitive mutants affecting gametic differentiation under nitrogen-starved conditions

Summary Two conditional mutants of Chlamydomonas reinhardtii, dif-1 and dif-2, affecting gametic differentiation under conditions of nitrogen (N)-starvation, have been isolated. These mutant cells remain vegetative at the restrictive temperature (35°C) in — N medium, as defined by assays of cell body-agglutinin and cell wall lytic enzyme activities in the soluble fractions of cell homogenates. Moreover, the mutants fail to form mating structures at the restrictive temperature, but do so at the permissive temperature (25°C). Temperature-shift experiments show that mutant cells which have differentiated into gametes at 25°C dedifferentiate into vegetative cells under N-starvation conditions after transfer to 35°C, but differentiate again into gametes at 25°C. Genetic analyses indicate that the dif-1 and dif-2 genes are recessive and unlinked to each other or to the matingtype locus; the dif-1 phenotype cosegregates with a conditional flagellales phenotype expressed in both +N and-N medium at the restrictive temperature.     

Chloride channel regulation in the skeletal muscle of normal and myotonic goats

External intercostal muscle biopsies from normal and congenitally myotonic goats were studied in vitro at 30° C using a two-microelectrode square-pulse cable analysis assisted by computer. The resting chloride conductance (G _cl) was estimated from the difference between the mean membrane conductance in chloride-containing and chloride-free bathing media. The protein kinase C (PKC) activator, 4--phorbol-12,13-dibutyrate, (0.1–2.0 M) blocks a maximum of 76% of G _cl in normal goat fibers and induces myotonic hyperexcitability similar to that of congenitally myotonic goat fibers. The G _cl block was partially antagonized by pretreatment with the PKC inhibitor, staurosporine (10 M). The inactive 4-phorbol-12, 13,didecanoate had no effect at 50 M, whereas the active 4- isomer blocked 41% G _cl at 1 M. The nearly absent G _cl of congenitally myotonic goat fibers was not restored by treatment with high concentrations of the PKC inhibitors staurosporine, 1-(5-isoquinolinesulfonyl)-2-methylpiperazine (H7), or tetrahydropapaveralone (THP). Also, forskolin and cholera toxin, which may increase cyclic adenosine monophosphate (cAMP) levels, or the R(+) clofibric acid enantiomers and taurine, which increase G _cl in normal fibers, were also unable to restore G _cl in myotonic goat fibers. The data suggest that PKC may be a chloride channel regulator in normal goat skeletal muscle fibers, however the molecular defect of congenitally myotonic fibers does not appear to be due to excessive activity of PKC.     

Muscle glycogen depletion during exercise at 9‡ C and 21‡ C

Summary This study compared glycogen depletion in active skeletal muscle after light and moderate exercise in both cold and comfortable ambient conditions. Twelve male subjects (Ss) were divided into two groups equally matched for the submaximal exercise intensity corresponding to a blood lactate concentration of 4 mM (W4) during cycle exercise. On two separate days Ss rested for 30 min at ambient temperatures of either 9 C or 21 C, with the order of temperature exposure being counter-balanced among Ss. Following rest a tissue specimen was obtained from the m. vastus lateralis with the needle biopsy technique. Six Ss then exercised on a cycle ergometer for 30 min at 30% W4 (range=50–65 W) while the remaining group exercised at 60% W4 (range=85–120 W). Another biopsy was taken immediately after exercise and both samples were assayed for glycogen content. Identical procedures were repeated for the second environmental exposure. No significant glycogen depletion was observed in the Ss exercising at 30% W4 in 21 C, but a 23% decrease (p=0.04) was observed when the same exercise was performed at 9 C. A 22% decrease (p=0.002) in glycogen occurred in the 60% W4 group at 21 C, which was not significantly different from that observed during the same exercise at 9 C. The results suggest that muscle substrate utilization is increased during light exercise in a cold environment as compared to similar exercise at a comfortable temperature, probably due to shivering thermogenesis. Heat produced with higher exercise intensities seems to be sufficient to prevent shivering and the accompanying glycogenolysis.     

Hydration during exercise

Summary Five young unacclimatised subjects were exposed for 4 h at 34 C (10 C dew-point temperature and 0.6 m · s^–1 air velocity), while exercising on a bicycle ergometer: 25 min work — 5 min rest cycles for 2 hours followed by 20 min work — 10 min rest cycles for two further hours. 5 experimental sessions were carried out: one without rehydration (NO FLUID) resulting in 3.1% mean loss of body weight ( M_b), and four sessions with 20 C fluid ingestion of spring water (WATER), hypotonic (HYPO), isotonic (ISO) and hypertonic (HYPER) solutions to study the effects of fluid osmolarity on rehydration. Mean final rehydration (±SE) after fluid intake was 82.2% (±1.2). Heart rate was higher in NO FLUID while no difference among conditions was found in either M_b or hourly sweat rates. Sweating sensitivity was lowest in the dehydration condition, and highest in the WATER one. Modifications in plasma volume and osmolarity demonstrated that NO FLUID induced hyperosmotic hypovolemia, ISO rehydration rapidly led to plasma isoosmotic hypervolemia, while WATER led to slightly hypoosmotic normovolemia.It is concluded that adequate rehydration through ingestion of isotonic electrolyte-sucrose solution, although in quantities much smaller than evaporative heat loss, rapidly restored and expanded plasma volume. While osmolarity influenced sweating sensitivity, the plasma volume changes ( PV) within the range –6% PV+4% had little effect on temperature adjustments in our conditions.     

Some of the swi genes of Schizosaccharomyces pombe also have a function in the repair of radiation damage

Summary In Schizosaccharomyces pombe the frequency of mating-type (MT) switching is reduced by mutations in the swi genes. The ten hitherto known swi genes can be subdivided into three classes: Ia, Ib and II. Strains having swi5 (class Ib), swi9 (class II) and swi10 (class II) mutations do not only show reduced MT switching, but also exhibit an increased sensitivity to UV- and -rays. For that reason, 19 previously described rad genes were tested for their effect on MT switching. We found that swi9, rad10, rad16 and rad20 are allelic with each other indicating that the former allocation of these rad mutations to three different genes must have been erroneous. Among the remaining 16 rad genes examined, rad22 seems to be a new class II swi gene. The double mutants swi5 swi9 and swi5 swi10, but not swi9 swi10, are much more sensitive to radiation than the respective single mutants. Thus a cumulative increase in sensitivity occurs only if the mutants belong to different classes; previously the same correlation was found with regard to cumulative effects in MT switching.     

A simple method for measurement of inulin in nanoliter samples using glass capillaries

Summary A simple method using glass capillaries instead of microcuvettes for measurement of inulin in nanoliter samples is given. Inulin was determined with anthron reagent (5 or 10 nl samples +3 l anthron reagent). Glass capillary tubes (o.d.=1 mm, i.d.=0.68 mm, length=150 mm) in which the chemical reaction took place during incubation at 56°C were directly introduced into the optical system of a Zeiss spectrophotometer PMQ II with sphere attachment and objective.Extinction was measured vertically to the axis of the capillary. The changes of extinction of 20 different capillaries with the blank at different positions was only 1.13×10^–3. The exactness of measurement in the concentration range of 100 200 400 750 1500 3000 mg-% inulin was for 5nl/3 l: 19.8 11.0 6.7 4.7 3.0 2.2%. 10nl/3 l: 13.0 8.4 5.1 3.9%.This method of measurement may also be applicable for other colorimetric reactions with nanoliter samples.This work was supported by Fonds zur Förderung der wissenschaftlichen Forschung.     

Reassessment of selective agars and filtration techniques for isolation ofCampylobacter species from faeces

Four different studies were conducted in order to re-evaluate conventional methods and assess the efficacy of new selective agars and a filtration method for the isolation of campylobacters. Skirrow's medium, Preston agar, modified CCD agar and Fennell's medium, incubated microaerobically at 37 °C for 48 h, gave similarCampylobacter isolation rates from 225 faecal samples, but the latter two media were more selective. Evaluation of modified CCD agar demonstrated that campylobacters could be isolated from that medium more successfully after incubation at 37 °C (173/177 positive samples) than at 42 °C (152/177 positive samples). In a larger study 1286 faecal specimens were cultured using modified CCD agar, Fennell's medium and a 0.45 µm membrane filtration technique, all incubated at 37 °C. Campylobacters were isolated from 89 % (178), 86 % (171) and 60 % (130) of 199 positive samples respectively. Modified CCD agar was most successful in isolation of the majority of campylobacters, but Fennell's medium was essential for recovery of Campylobacter cinaedi andCampylobacter fennelliae, whereas the 0.45 µm membrane technique was the only method to isolate all of the catalase-negative campylobacter strains. Further evaluation of the 0.45 µm and 0.65 µm pore size membranes showed that more strains ofCampylobacter jejuni andCampylobacter coli were isolated using the larger pore size membranes.     

Expression of surface membrane IgG on pokeweed mitogen-reactive anti-tetanus toxoid antibody-producing cells

Anti-tetanus toxoid antibody-producing cells, differentially expressing surface membrane IgM, were analyzed for the additional expression of surface membrane IgG. ⁺ and ^– cells were rosetted with anti--ox red blood cells and separated by density centrifugation into fractions enriched or depleted or ⁺ cells. These B-cell subsets were assayed for the production of IgM and IgG anti-tetanus toxoid antibody and total IgM and IgG. The results indicated that the majority of anti-tetanus toxoid antibody synthesis in the ^– fraction was by ⁺ cells. In the ⁺ fraction, however, both IgM and IgG anti-tetanus toxoid antibody production was detected in the ^+– and ⁺⁺ fraction. The inclusion of isotype-specific antisera during the first 2 days of culture further established that was expressed on the surface of the majority of the precursors for IgG anti-tetanus antibody productionin vitro. Studies performed to determine the culture requirements of ^– and ⁺ cells revealed that production of IgG anti-tetanus toxoid antibody by both cell subsets was dependent on T cells and pokeweed mitogen. However, some ^– cells could produce IgG in the presence of T cells alone.     

Neuron Activity in the Prefrontal Cortex of the Brain in Rats with Different Typological Characteristics in Conditions of Emotional Stimulation

Male Wistar rats were separated according to the emotional resonance method (groups of animals avoiding (altruists) and not avoiding (egotists) the pain cries of partner rats) and neuron activity in the prefrontal areas of the cortex was studied in the right and left hemispheres. Assessments were made of changes in the frequency of nerve cell spike activity (in relation to the baseline activity of neurons in sated animals) in rats subjected to one day of food deprivation and after electrical stimulation of emotionally positive (lateral hypothalamus) and negative (tegmentum of the midbrain) brain structures and after exposure to the pain cries of partner rats. The results of these experiments revealed a series of differences in the cell activities of the two groups of rats. In conditions of hunger, the discharge frequency in the altruists was higher than that in egotists. Cortical neuron responses to positive stimulation were greater than those to negative stimulation in rats of both groups. Intracerebral stimulation produced significantly greater increases in discharge frequency in neurons of both prefrontal areas of the cortex in altruists than in egotists. In both groups of rats, neurons in the right hemisphere responded to emotionally negative stimulation with significantly greater activation than cells in the left hemisphere, while activity in the left hemisphere was greater in conditions of emotionally positive stimulation. Altruists showed significantly greater neuron responses during exposure to pain cries from victim rats in both the right and left hemispheres. The responses of egotists to victim cries were not significantly different from baseline activity levels.     

Elektronenmikroskopische Cytomorphologie der Gynäkomastie

Zusammenfassung Anhand von 5 elektronenmikroskopisch bearbeiteten Fällen wird die Cytomorphologie der Gynäkomastie beschrieben und mit der Feinstruktur der Mamma virilis verglichen. Histologisch lag übereinstimmend die häufige tubuläre Gynäkomastie-Form vor.1. Licht- und elektronenmikroskopisch ist die Gynäkomastie durch eine Hyperplasie des Gangepithel gekennzeichnet. Es überwiegen hochprismatische helle Zellen, sog. Hauptzellen. Durch Kompressionen im Zellverband werden die Epithelzellen passiv verformt. Dadurch bilden sich am apikalen Pol der Zellen Protuberanzen des Cytoplasmas, die abgeschnürt werden und in das Lumen gelangen können. Dieser Vorgang wird allgemein als apokrine Sekretion bezeichnet. Elektronenoptisch handelt es sich nicht um Mechanismen eines echten Sekretionsvorganges mit Bildung von Sekret.2. Epithelknospen und -brücken bestehen aus Epithelverbänden, die durch Desmosomen zusammengehalten werden. Superfiziale Zellen zeigen verschiedene Grade regressiver Veränderungen und der Zelldesquamation an. Als Ausdruck der Zellproliferation werden häufig Centriole beobachtet und als Sonderformen Satelliten und sog. Rootlets beschrieben.3. Wie das Drüsenepithel unterliegen auch Myoepithelzellen dem Proliferationsimpuls bei Gynäkomastie. Die Hyperplasie des Myoepithels hat wahrscheinlich für die Entwicklung besonderer Basalmembranstrukturen Bedeutung.4. Das aufgelockerte circumtubuläre Mantelgewebe als mesenchymales Kennzeichen der Gynäkomastie enthält elektronenoptisch wenig kollagene Fibrillen und granulär-flockige Präzipitate einer Hyaluronsäure-haltigen Grundsubstanz.

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The electron microscopic cytomorphology of gynecomastia

Summary The electron microscopic cytomorphology of gynecomastia is described in 5 patients cases (aged from 17 to 71 years) and compared with the fine structure of the male mammary gland. The histologic features in these cases are characterised by tubular proliferation with elongation and branching of ducts, the so-called tubular form of gynecomastia.1. The gynecomastia is characterized by hyperplasia of duct epithelium. The main cell types are prismatic clear cells. Due to compressions in the sheets of epithelial cells the single cells lose their original shape. In the apical poles of the cells protrusions of cytoplasm develop that are discharged into the lumina of the ducts. Commonly this is called apocrine secretion. Electron microscopic investigations show no mechanism of true secretion of cellular products, such as secretory droplets. This applies to most cases of gynecomastia of the tubular form described here.2. Buds and bridges of epithelium, one of the most distinctive features of gynecomastia, are held together and stabilised by chains of desmosomes. Many forms of regressive metamorphoses and of cell desquamation occur in the superficial cells. A sign of permanent proliferation and hyperplasia of epithelial cells is the occurrence of many centriols. Sporadically the centriols are connected with satellites and rootlets.3. In gynecomastia myoepithelial cells are also proliferated. This phenomenon may cause the development of special structures of the basement membrane.4. The connective tissue in gynecomastia is separated into the circumductal or circumlobular tissue (the so called mantletissue) and the interductal or interlobular (or supporting tissue). The circumductal tissue is the mesenchymal trademark of gynecomastia. Electron microscopically it contains only few collagen fibrils and granular prepicitations of ground-substance partly composed of hyaluronic acid.

     

Influence of ambient temperature on calorigenic action of thyroid hormones in young mice

In 5- and 7-day-old HAICR mice the calorigenic action of thyroxine (T₄) and triiodothyronine (T₃) was investigated at different ambient temperatures. After treating animals with 5 g T₄ or 1 g T₃ per g body weight and day, their oxygen consumption was compared with that of litter mate controls at 23°, 27°, 31° and 35°C. The hormone action was highly dependent on ambient temperature, 1 g T₃ being most effective. A thyroid hormone effect could never be observed at 31°C, the animals' nest temperature. By application of propranolol, which almost selectively blocks nonshivering thermogenesis (NST), we could show that T₃ increases minimal oxygen consumption (MOC) as well as the capacity for NST. In addition, it could be shown that also oxygen consumption of liver tissue of 5-day-old mice is elevated by preceding treatment with thyroid hormones. The ambient temperature effects are discussed in relation to the thermoregulatory situation of the mice during the early postnatal period.     

The effect of praziquantel on the pseudophyllidean cestodeBothriocephalus acheilognathi in vitro

AdultBothriocephalus acheilognathi were incubated in solutions containing 0 (control), 0.1, 1.0, 10.0 and 100 g praziquantel per ml (0, 10², 10³, 10⁴ and 10⁵ gl^–1) of 0.9% saline for 5, 15 and 60 min at a temperature of 18°C. The worms contracted immediately upon being placed in the drug. Scanning and transmission electron microscopy revealed considerable tegumental damage particularly in the neck region. Vacuolization and bubbling to the tegument occurred in all of the drug solutions tested. Exposure to drug concentrations of more than 1.0 gml^–1 (10³ gl^–1) praziquantel for 15 min or greater resulted in many of the bubbles bursting and releasing their contents to the exterior. Mature proglottides were distorted and had occasional large swellings resulting in the mass expulsion of eggs. Praziquantel had no ovicidal activity. Exposure to drug concentrations of 100 g (10⁵ gl^–1) praziquantel per ml saline for 24 h was not lethal to the worms.     

Identification and quantitation of cortisol metabolites in rat liver homogenate and -slices

Summary Cortisol-1, 2-H³ was incubated with rat liver homogenate and/or rat liver slices in the presence of a NADPH-generating system. The following metabolites could be identified in adult male rats: -cortol, allo--cortol, 3-allo--cortol, 20-hydroxy-cortisol, 11, 17, 20, 21-tetrahydroxy-5-pregnan-3-one, 3-allotetrahydrocortisol, tetrahydrocortisol, trace amounts of allotetrahydrocortisol and two highly polar metabolites only partly identified. In female rats only tetrahydrocortisol, allotetrahydrocortisol and allodihydrocortisol could be detected in significant amounts.The radioactive metabolites mentioned above were localized and quantitated on paper chromatograms by a 4-radiochromatogram scanner. A nearly perfect correlation was found between these results so obtained and those given by liquid-scintillation counting of each metabolite after its elution from the paper.Part of this work was supported by grant n° 695 of the National Fonds voor Wetenschappelijk Geneeskundig Onderzoek.Stagiair of the Nationaal Fonds voor Wetenschappelijk Onderzoek.     

IFN-β-Therapie bei der Haarzelleukämie

Zusammenfassung 11 Patienten mit einer Haarzell-leukämie wurden zwei bis sechs Monate lang mit Beta-Inferferon (IFN-; 3 × 4 Mio. I.E./Woche i.v.) behandelt. Von 8 auswertbaren Patienten erreichten 3 eine partielle Remission, 2 eine minor response, während 3 Patienten keine Verbesserung ihrer hämatologischen Werte zeigten. Als Nebenwirkungen traten die für die IFN-Therapie typischen grippeähnlichen Symptome bei 9 der 11 behandelten Patienten auf. Bei einem Patienten wurde ein Rückgang der Knochenmarksinfiltration unter IFN- beobachtet. Diese Daten zeigen, daß IFN- bei der Haarzelleukämie wirksam ist.

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Interferon-beta therapy in hairy cell leukemia

Summary Eleven patients with histologically proven hairy-cell leukemia were treated for 2 to 6 months with a natural beta-interferon (-IFN) preparation (3 × 4 million units week i.v.). Three of the eight evaluable patients experienced a partial response, two a minor response, and three no improvement. A reduction of the hairy-cell infiltration of the bone marrow was observed in one patient. Typical IFN side-effects with flu-like symptoms were noted. These results demonstrate that IFN- has some clinical efficacy in hairy-cell leukemia.

     

Decontamination studies with the agents of bovine spongiform encephalopathy and scrapie

Summary Macerates of bovine brain infected with bovine spongiform encephalopathy (BSE) agent, and rodent brain infected with the 263K or ME7 strains of scrapie agent, were subjected to porous-load autoclaving at temperatures between 134 and 138 °C for 60 min. Bioassay in rodents showed that none of the regimes produced complete inactivation. Homogenates of BSE-infected bovine brain were exposed for 120 min to solutions of sodium hypochlorite or sodium dichloroisocyanurate containing 16,500 ppm available chlorine. There was no detectable survival of infectivity after the hypochlorite treatments but none of the dichloroisocyanurate solutions produced complete inactivation. Homogenates of BSE-infected bovine brain, and rodent brain infected with the 263K and ME7 strains of scrapie agent, were exposed for 120 min to 1M or 2M sodium hydroxide but no procedure produced complete inactivation of all agents tested.