Brain neurons and glial cells express Neu differentiation factor/heregulin: a survival factor for astrocytes.

Neu differentiation factor (NDF, also called heregulin) was isolated from mesenchymal cells on the basis of its ability to elevate phosphorylation of ErbB proteins. Earlier in situ hybridization analysis showed that NDF was transcribed predominantly in the central nervous system during embryonic development. To gain insights into the role of NDF in brain we analyzed its distribution by immunohistochemistry and in situ hybridization. Late-gestation (day 17) rat embryos displayed high NDF immunoreactivity in both motor (e.g., putamen) and limbic (e.g., septum) regions. Lower levels of the factor were exhibited by adult brain, except for the cerebellum, where NDF expression was increased postnatally. Both neurons and glial cells were identified by immunohistochemistry as NDF-producing cells (e.g., pyramidal neurons in the cerebral cortex and glial cells in the corpus callosum). By establishment of primary cultures of rat brain cells we confirmed that NDF was expressed in neurons as well as in astrocytes. In addition, by using such primary cultures we observed that NDF treatment exerted only a limited mitogenic effect, which was accompanied by significant acceleration of astrocyte maturation. Furthermore, long-term incubation with the factor specifically protected astrocytes from apoptosis, implying that NDF functions in brain as a survival and maturation factor for astrocytes.     

Anaphylaxis to omeprazole: diagnosis and desensitization protocol.

BACKGROUND: Omeprazole is an inhibitor of the parietal cell enzyme H+/K+ adenosine triphosphatase. Immediate-type hypersensitivity reactions, such as urticaria, angioedema, and hypotension, induced by omeprazole and other proton pump inhibitors are rare. OBJECTIVES: To confirm the immediate-type mechanism of recurrent anaphylactic reactions to the repeated administration of omeprazole using skin testing and to enable safe administration of the drug after successful oral desensitization. METHODS: Intradermal skin tests were performed with omeprazole (0.04 and 0.4 mg/mL) prepared from the oral and intravenous commercial preparations and with pantoprazole (0.02 and 0.2 mg/mL) prepared from the oral commercial preparation. Skin tests were repeated after completion of the desensitization. Oral desensitization was applied at a starting dose of 0.001 mg of omeprazole, and a full dose of 16 mg was achieved after 5.6 hours (cumulative dose of 32.6 mg). RESULTS: Intradermal skin test results were positive to omeprazole and pantoprazole at all tested concentrations. After successful desensitization, omeprazole was administered in the full dose uneventfully. The wheal size of the intradermal skin tests performed after completion of the desensitization was significantly reduced. CONCLUSION: When indicated, this newly designed desensitization protocol may be used in patients with omeprazole-induced anaphylaxis.     

Sequential respiratory syncytial virus cytomegalovirus pneumonia following bone marrow transplantation

A 6-month-old child with familial hemophagocytic lymphohistiocytosis (FHL) experienced early sequential pneumonia due to respiratory syncytial virus (RSV) and cytomegalovirus (CMV) following bone marrow transplantation (BMT). The patient was deficient in natural killer (NK) cell activity (as found frequently in patients with FHL), and this risk factor may have played a major role in the concomitant infection by the two viral pathogens. Rapid diagnostic methods for both viruses are essential and early specific treatment may serve to ameliorate RSV- and CMV-induced lung injury in these life-threatening infections. © 1995 Wiley-Liss, Inc.     

Pathological confirmation of cystic fibrosis in the fetus following prenatal diagnosis

Prenatal diagnosis of cystic fibrosis is presently based on the determination of microvillar enzyme activities in the amniotic fluid. However, there seems to be no accurate means for confirming the diagnosis of the aborted fetus. During the past year we performed pathological and histopathological examinations on 7 fetuses diagnosed in the second trimester of pregnancy to be affected by cystic fibrosis and compared them with 4 control age-matched fetuses. Glycol-methacrylate-embedded 2-3-mu thick sections of the pancreas, lungs, bronchial tree, and GI tract were stained with toluidine blue, H&E, PAS, and AB-PAS, and examined microscopically. In the controls, PAS-positive granules were dispersed throughout the cytoplasm of most pancreatic acinar and tracheal submucosal glandular cells. In the affected fetuses 2 distinct groups were identified. In one group of 4 fetuses, the pancreatic and tracheal submucosal glands were dilated and contained a weak PAS-positive material. The glandular epithelial cells had very little PAS-positive granules. In this group, the tracheal epithelium was either atrophic or metaplastic and devoid of microvilli. In the second group of 3 fetuses there was less dilation of the glands, and both pancreatic acinar cells and tracheal submucosal glandular epithelial cells contained few PAS-positive granules, which were confined mainly to a perinuclear location. The tracheal epithelial cells contained few microvilli which, when present, appeared thicker and shorter as compared to controls. We feel that histochemical evaluation of pancreatic and bronchial tissue may be of help in the pathological confirmation of cystic fibrosis in human fetuses where the results of the biochemical studies are suggestive of the disease.     

A small-animal activity-analysing system for behavioural studies

Automated recording and data analysis of the activity of small laboratory animals are often required for psychological and other forms of behavioural investigation. This paper describes such a system using an open field of 1·14×1·14 m. Three arrays of infrared-light-emitting diodes and phototransistors are used to locate the animal. Two of the arrays are used to generate an xy grid, while the third one is used to determine whether the animal is rearing. The position of the animal gives rise to both digital and analogue signals; so the equipment can be interfaced directly with a minicomputer, or coupled to an analogue recorder. Several activity parameters, such as the path length (absolute value of the line integral), the time spent at a predetermined area of the open field or the latency to move, are computed and displayed in digital form.     

Reproducibility of skin testing and serum venom specific IgE in Hymenoptera venom allergy.

BACKGROUND: The decision regarding an immunotherapy regimen for venom-allergic patients is based on the results of skin testing and serum venom specific IgE measurements. However, their reliability has been questioned, and their reproducibility has not been examined. OBJECTIVE: To evaluate the reproducibility and reliability of the results of skin testing and serum venom specific IgE measurement in venom-allergic patients. METHODS: Patients with a systemic reaction after an insect sting were evaluated twice, 2 to 6 weeks apart, by intradermal skin tests and by determination of serum venom specific IgE to Hymenoptera venoms. RESULTS: Thirty-five patients were evaluated 1 to 168 months (mean, 23 months) after the sting reaction. Reproducibility of skin test results for all venoms at the 2 sessions was found in 23 patients (66%). Reproducibility of venom specific IgE results for all venoms was found in 16 (59%) of 27 patients from whom 2 blood samples were available for evaluation. Concordance between skin test and venom specific IgE results for all venoms was found in 30 (51%) of 59 samples available for evaluation. CONCLUSIONS: The reproducibility of venom skin test and serum venom specific IgE results is relatively poor. It is common practice for therapeutic decisions regarding venom immunotherapy to be based on a single diagnostic evaluation. Consequently, many patients are either overtreated or undertreated. Better diagnostic methods are required in venom allergy.     

Computerized cognitive testing in patients with type I Gaucher disease: effects of enzyme replacement and substrate reduction.

PURPOSE: Because of concern for drug-induced cognitive dysfunction during clinical trials using substrate reduction therapy (miglustat) in type 1 Gaucher disease and because it has been suggested that some patients with type 1 Gaucher disease may develop neurocognitive impairment as part of the natural history, two different batteries of neuropsychological tests were devised to examine these issues. Using these tests, cognitive function was assessed in patients treated with miglustat, in patients receiving enzyme replacement (standard care for symptomatic patients), and in untreated (milder) patients. METHODS: For this study, 55/60 patients exposed to miglustat in Israel participated in psychologist-administered testing; 36/55 participated in computerized testing. Of these, 31 enzyme-treated patients and 22 untreated patients participated in the psychologist-administered testing, and 15 enzyme-treated patients and 18 untreated patients participated in computerized testing. The psychologist-administered battery consisted of 18 standard neuropsychological subtests specific to executive and visuospatial functioning. The computerized battery (Mindstreams, NeuroTrax Corp., New York, NY) consisted of 10 subtests tapping multiple cognitive domains. Between-group analyses for each modality compared cognitive performance. RESULTS: In the psychologist-administered testing, patients exposed to miglustat performed significantly less well than the other groups in 5/18 subtests. On the computerized tests, all patients performed comparably to normal controls. Scores in patients exposed to miglustat were higher than in untreated patients, particularly in visuospatial function, whereas enzyme-treated patients performed less well. However, with the exception of visuospatial function, these results were not statistically significant. CONCLUSIONS: It is unclear why different testing methods yielded discordant results. Any dysfunction suggested by the current study is apparently subtle and of doubtful clinical relevance given that cognitive status did not interfere with patients' daily intellectual function. The computerized battery has methodological advantages (e.g., language options, objectivity, brevity, and ease of use) that make it well-suited for longitudinal studies, for long-term surveillance of substrate reduction therapy as well as for comparisons with other lysosomal storage disorders and other chronic diseases. These preliminary findings should allay fears of cognitive dysfunction due to short-term miglustat therapy.     

Amino acid substitutions within the heptad repeat domain 1 of murine coronavirus spike protein restrict viral antigen spread in the central nervous system

Targeted recombination was carried out to select mouse hepatitis viruses (MHVs) in a defined genetic background, containing an MHV-JHM spike gene encoding either three heptad repeat 1 (HR1) substitutions (Q1067H, Q1094H, and L1114R) or L1114R alone. The recombinant virus, which expresses spike with the three substitutions, was nonfusogenic at neutral pH. Its replication was significantly inhibited by lysosomotropic agents, and it was highly neuroattenuated in vivo. In contrast, the recombinant expressing spike with L1114R alone mediated cell-to-cell fusion at neutral pH and replicated efficiently despite the presence of lysosomotropic agents; however, it still caused only subclinical morbidity and no mortality in animals. Thus, both recombinant viruses were highly attenuated and expressed viral antigen which was restricted to the olfactory bulbs and was markedly absent from other regions of the brains at 5 days postinfection. These data demonstrate that amino acid substitutions, in particular L1114R, within HR1 of the JHM spike reduced the ability of MHV to spread in the central nervous system. Furthermore, the requirements for low pH for fusion and viral entry are not prerequisites for the highly attenuated phenotype.