Biomedical subjects
Publications and source records attributed to P Fischer.
Ideomotor apraxia, tested on verbal command and by imitation, was checked in 23 patients suffering from dementia of Alzheimer's type of different severity and in 17 age-matched controls. A significant deterioration of ideomotor praxis could be shown even in mild dementia. Correlations of ideomotor apraxia and aphasia, tested by the Token test were found to be significant.
In the spring and summer of 1989 an epidemiologic study was conducted to evaluate the acute effects of photochemical air pollution episodes on pulmonary function of children living in three nonindustrial towns in the Netherlands. Spirometry was performed repeatedly in the schools of the children, mostly during the morning hours. Data from 533 children having more than four valid pulmonary function tests were included in the analyses. The association between previous-day ambient ozone concentration and pulmonary function was evaluated, using individual linear regression analysis and subsequent evaluation of the distribution of individual regression coefficients. One hour maximum ambient ozone concentrations frequently exceeded 160 micrograms/m3 but were all lower than the Dutch Air Quality Guideline of 240 micrograms/m3 for all three populations. Significant negative associations of previous-day ambient ozone with FVC, FEV1, peak expiratory flow (PEF), and maximal midexpiratory flow (MMEF) were observed. There were indications of systematic differences in responses among the children. Children with chronic respiratory symptoms did not have a stronger response than children without these symptoms.
To determine whether the presence of ungulates may inhibit transmission of the agent of Lyme disease (Borrelia burgdorferi) while promoting the abundance of its European vector tick (Ixodes ricinus), we compared the feeding density of subadult ticks on roe deer (Capreolus capreolus), red deer (Cervus elaphus), fallow deer (Dama dama), and wild sheep (Ovis ammon) near Berlin and in Brandenburg State, Germany. The prevalence of spirochetal infection in these ticks was compared with that in ticks swept from nearby vegetation. Spirochetes are present in nearly one-fifth of nonfed, questing nymphal and adult wood ticks in the region. Many ungulates in this intensely enzootic region fail to mount a detectable humoral response against the agent of Lyme disease, even when exposed to numerous infected ticks. During the height of the summer, each ungulate may support the feeding of hundreds of subadult ticks. Larvae feed lower on the bodies of hoofed game than do nymphs. Few ticks retain infection by the Lyme disease spirochete after feeding on hoofed game animals. We conclude that numerous I. ricinus ticks feed on ungulates, but that such host-contact fails to infect these ticks while eliminating pre-existing spirochetal infection.
In the forests of western Uganda onchocerciasis is transmitted by Simulium neavei s.s. Since little is known about the infection transmitted by this vector, a survey was made in 1991 with special regard to adult persons of 15 years and older in the 13 villages of the parish Kigoyera 40 km northeast of Fort Portal. 3268 (52%) of the 6271 registered inhabitants were examined clinically and parasitologically. The highest microfilaria (mf) densities were found on the buttocks, lower ones on the shoulders and the lowest on the ankles. In the parish the standardised prevalence of mf carriers was 62%. The crude prevalences of adult mf carriers ranged from 80% to 95% in the 13 villages. Densities of 100 mf/snip or more were found in 25% of male persons. The community microfilarial load (CMFL) in skin snips from the buttocks was 49 mf/snip, ranging from 22 to 93 in the 13 villages. The standardised prevalence of nodule carriers was 25% and the mean nodule load was 1.9 nodules per nodule carrier. Among 3420 nodules 90% were found on the pelvic girdle. The standardised prevalence of onchocercal dermatitis was 19%. The crude rates ranged within the age groups in males from 20% to 45% and in females from 16% to 41%. The standardised prevalence of persons presenting mf in the anterior chamber of the eye was 24% and the CMFL in the anterior chamber ranged between 1.2 and 3.3 mf/chamber in six villages. Standardised rates were 1.6% for sclerosing keratitis and 0.9% for reduced vision of 3/60 or less. These prevalences of eye lesions are comparable to those observed in West African forest areas. The CMFLs and the prevalences of mf and nodule carriers represent suitable criteria for community diagnosis of S. neavei-transmitted onchocerciasis in Uganda to guide ivermectin treatment, whereas the prevalence of "leopard skin" is not useful. Immigrants living less than five years in the endemic focus should be excluded from the assessment of mf carrier rates and those living there less than ten years from rapid assessment of nodule carrier rates.
This paper describes the behaviour disturbances and emotional problems of Turkish immigrant children aged 9 to 13 years living in Vienna. The children's behaviour was rated with Rutter's scales and the relationship of the results to any language problems, the socioeconomic situation and the sociocultural background of the immigrant families was then analyzed. A consecutive series of 111 Turkish and 25 Austrian children were rated by their parents and by both Turkish- and German-speaking teachers. Psychiatric symptoms of the children's parents were assessed with the symptom checklist SCL-90. The prevalence of behavior problems did not differ between the Turkish and Austrian children, who were of similar social class. The most common symptoms were restlessness, overactivity, poor concentration and anxiety. Whereas socioeconomic and sociocultural factors did not influence the frequency or severity of behavior problems in the Turkish children, there was a highly significant relationship between behavior problems and problems with German or Turkish. Moreover, the children very frequently had problems with both languages. Therefore intervention strategies with such children should focus on the language problems.
A new human T-cell non-Hodgkin lymphoma cell line of the T-cell receptor (TCR) gamma/delta lineage has been derived from the peripheral blood of a patient with a subcutaneous T-cell lymphoma in leukemic phase. The cell line (Karpas 384) initially had the same characteristics as malignant cells from the patient. Both the original tumor and the cell line failed to express any T-cell differentiation antigens other than very weak cell-surface expression of CD3 and cytoplasmic CD7; with continued growth in vitro, surface CD3 became undetectable in the presence of maintained strong cytoplasmic expression. The cell line has a complex karyotype with six abnormal chromosomes exhibiting not only t(7;14) (p13;q11.2) but also inv7(p13;q22.1), t(1;2)(q11;q35), t(2;1;14) (q35;q11-q32.1;q22.1), interstitial deletion 12(q24.1q24.3), and an unidentified marker chromosome. DNA blot analysis showed that TCR C beta and TCR J alpha-C alpha DNA sequences were in germline configuration in all restriction endonuclease digests. TCR gamma sequences showed biallelic V gamma 9-J gamma P-C gamma 1 rearrangements, the TCR gamma rearrangement detected in the majority of normal TCR gamma/delta bearing cells. Use of a range of TCR delta probes showed biallelic deletion of both J delta 1 and J delta 2, but three rearranged fragments when probed with a 3' C delta genomic probe. Similar breakpoints at 7p13 have been reported in a wide range of hematologic malignancies. Molecular cloning of the t(7;14)(p13;q11.2) translocation breakpoint in this cell line may define new DNA sequences of oncogenic potential at the 7p13 locus.
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Antibodies are usually prepared from recently boosted animals and reflect ongoing immune responses. In humans, this is restrictive as ethical constraints generally prevent antigen-boosting. Therefore the rich memory compartment of human antibody responses remains largely untapped. Severe combined immune deficiency (SCID) mice populated with human cells allow the stimulation of human antibody memory without the usual constraints. Here we show how peripheral blood lymphocytes can be stimulated by antigen to produce large secondary responses after transfer to SCID mice. Specific monoclonal human Fab fragments can then be isolated from the mice by repertoire cloning even when the human donor's last contact with antigen was more than 17 years ago.
To more closely define the risk of infection by the agent of Lyme disease in Europe, we determined whether spirochetal prevalence increases throughout the development of the Ixodes ricinus vector tick. Of all ticks that could be flagged from vegetation, I. ricinus were by far the most abundant. Spirochetal infection rates in the adult stage of this tick (15%) are no higher than those in nymphs (18%) but greatly exceed those in larvae (0.7%). This tick therefore appears to attain infection mainly from the host of its larval stage, generally feeds on hosts that are noncompetent as reservoirs in its nymphal stage, and rarely inherits infection. Risk of human infection mainly derives from contact with the nymphal stage of the vector tick because the larva is rarely infected and the adult is large enough to be noticed and promptly removed.
Monoclonal antibody 138H11 against human gamma-glutamyltransferase has been shown to react immunohistochemically with 98% of all tested clear-cell type and chromophilic renal cell carcinomas, but not with renal chromophobic carcinomas, Duct-Bellini carcinomas or oncocytomas. In normal kidney the target epitopes of mAb 138H11 are located in the luminal brush-border membrane of proximal tubule cells, whereas in renal carcinomas the epitopes are found surrounding the whole tumour cells. These results form the basis of the present immunoscintigraphic study designed to evaluate mAb 138H11 in an extracorporeal perfusion model. Immediately after nephrectomy, human tumour-bearing kidneys were perfused with 99mTc-labelled mAb 138H11 in Euro-Collins solution. High specific uptake in 4/4 renal clear cell carcinomas could be demonstrated by planar immunoscintigraphy and single-photon-emission computed tomography, "regions of interest" investigation and immunohistochemistry. In contrast, a perfused oncocytoma showed up as an unlabelled lesion. The results indicate a possible use for mAb 138H11 in immunoscintigraphy or even therapy, provided high tumour uptake can be confirmed in patients.
Release signs have been described in both age-associated diseases and in the healthy elderly. We investigated the palmomental, snout, grasp, corneomandibular and glabellar reflexes in demented and non-demented Parkinson-patients compared to Alzheimer's disease and age-matched controls. The palmomental reflex and a persisting glabellar reflex were linked to parkinsonism irrespective of dementia and were found also in Alzheimer's disease. A corneomandibular reflex was observed more frequently in demented than non-demented Parkinson-patients and in Alzheimer's disease. The snout-reflex was present in nearly all individuals irrespective of diagnosis. Thus, various release signs react quite differentially to degenerative brain disease and dementia.
An unusual case of variant HCL with multiple ribosomal lamellar complexes and complex chromosomal changes is described. The karyotype of the main cell clone is characterized by involvement of chromosome 5 at q13.3 and interstitial deletion of 7q. However, there is no other evidence of myelodysplasia and the abnormal cells are of lymphoid origin with a B-cell immunophenotype. The clonal chromosomal evolution involves rearrangements at sites known to be specifically altered in lymphoid tumors.
We have analysed several markers for small synaptic vesicles (synaptin-synaptophysin, p65 and SV2) and large dense-core vesicles (chromogranin A, secretogranin II/chromogranin C) in the brains of patients with Alzheimer's disease, and normal controls by immunoblotting and immunohistochemistry. In comparison to age-matched controls the levels of all three synaptic vesicle markers were decreased in temporal cortex of Alzheimer patients. On the other hand, the levels of chromogranin A were increased, and those of secretogranin II lowered. This resulted in a significant increase of the ratios of chromogranin A to synaptophysin, p65 or SV2 and of that for chromogranin A to secretogranin II. These increases were significantly correlated to clinical severity of dementia and extent of neuropathological changes. By immunohistochemistry a high percentage of senile plaques was found to contain chromogranin A-reactive dystrophic neurites, whereas synaptophysin reactivity within plaques was rare. These results indicate that the number of synaptic vesicles is lowered in Alzheimer's disease, and that one component of large dense-core vesicles, i.e. chromogranin A, is elevated. We, thus, suggest that in Alzheimer's brain distinct changes occur for both types of synaptic organelles.
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The abundance of spirochete-infected Ixodes ricinus ticks naturally derived from endemic rodents was compared to identify the reservoir hosts of the agent of Lyme disease at a series of enzootic sites in Central Europe. Black-striped mice appear to be the most important rodent host for the tick and infect more ticks with Borrelia burgdorferi than do other mice and voles tested. Although rodents infect about half of the ticks that feed on them, lizards infect none. These spirochete-incompetent hosts dilute the force of transmission because many nymphal ticks feed on them. Older male hosts are more heavily infested by subadult ticks than are younger or female hosts. The intensity of transmission of the agent of Lyme disease at particular Central European sites appears to correlate directly with the presence of black-striped mice and inversely with that of lizards.
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The presence of viable mould propagules in indoor air was investigated using the N6-Andersen sampler in combination with DG18-agar, in relation to house damp (characterized with a checklist) and in relation to the presence of moulds in outdoor air. The first part of the study was conducted in 46 houses in the autumn of 1987, the second part in 84 houses in May 1989. Further, in the second part, the results obtained with settlement plates (OPD) were compared with those obtained with the N6-Andersen sampler. The number of CFU/m3 in the indoor and outdoor air varied widely. A large variety of mould genera and species was isolated. Species of Cladosporium, Penicillium and Wallemia predominated. The variability in time was high and the reproducibility of the measurements in terms of CFU/m3 and of species isolated was only moderate. The low predictive value of these measurements limits their use in epidemiological studies of the relationship between exposure to moulds and respiratory symptoms. Overall, the geometric mean concentration was somewhat higher outdoors than indoors. However, the clear differences found between the number of CFU/m3 belonging to different mould species in in- and outdoor air show that the presence of viable mould propagules in indoor air is not simply a reflection of the presence of moulds in outdoor air. The presence of moulds in indoor air was only weakly related to house damp as characterized by the checklist. High, statistically significant correlations were found between the CFU yield obtained with the OPD and the CFU/m3 yield obtained with the N6-Andersen sampler.(ABSTRACT TRUNCATED AT 250 WORDS)