Search PubMed⌕ Search

Biomedical subjects

H Ludwig

Publications and source records attributed to H Ludwig.

At least 181 records · Page 10Linked to original sources
PubMed1993

Natural Borna disease in domestic animals others than horses and sheep.

In 24 cats (Uppsala, Sweden) with neurological signs of "staggering disease" and typical neuropathology, 44% had Borna disease virus (BDV)-specific antibodies. In 173 cat sera (Berlin, Germany) of animals with unknown record, 7% were BDV positive. Out of 24 cats with undefined neurological disorders, 13% were BDV positive. Similarities in staggering disease of cats and Borna disease of horses and sheep suggest related etiological agents.

Animals↗
PubMed1993

Interferon-alpha stimulates the hypothalamic-pituitary-adrenal axis in vivo and in vitro.

The successful therapeutic use of interferon-alpha (IFN-alpha) in myeloproliferative disorders offered the possibility to test its acute and long-term effects on the hypothalamic-pituitary-adrenal (HPA) axis in humans. ACTH and cortisol plasma concentrations were measured in 8 patients hourly starting from 4 p.m. through 12 p.m. on three occasions. The first time all patients were studied before initiation of therapy, when the vehicle was injected alone. The patients were studied again on day 1 of IFN-alpha therapy (5 million units) and once more after 3 weeks of therapy. On the control day, plasma concentrations of ACTH and cortisol were in the range expected for this time of day. In contrast, after the first administration of IFN-alpha a significant stimulation of the HPA axis was observed. After 3 weeks of IFN-alpha therapy, no significant stimulation of the HPA axis occurred after administration of IFN-alpha. IFN-alpha-induced adaptive changes in the HPA axis were also indicated by a significantly enhanced ACTH and cortisol response to exogenously administered supramaximal doses of corticotropin-releasing hormone (CRH) when the patients had been on IFN-alpha treatment for 3 weeks. To determine the exact locus of the IFN-alpha action, in vitro experiments were performed using rat hypothalamic organ and primary pituitary and adrenal cell culture systems. Thereby a significant stimulation of hypothalamic CRH secretion and rat adrenal corticosterone production was observed after INF-alpha at concentrations of 5 x 10(-8) M or 10(-7) M respectively. In contrast, no direct IFN-alpha effect on pituitary ACTH secretion could be observed in vitro.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenal Glands↗
PubMed1993

[Development of the female breast].

The decision, whether or not an abnormality of breast development needs consideration, fundamentally depends on the knowledge of the time sequence of thelarche, menarche and pubarche. Their occurrence is normally one to two years apart. Neonatal hypertrophy or asymmetries are frequent and do not need treatment. Painful enlargement of the breast might appear during puberty and can be treated symptomatically or with progestogen gel. Persistent micromastia or macromastia (virginal hypertrophy) is a more serious event. After thoroughful consultation the patient might be referred to the plastic surgeon. If the breast development is deficient after the age of 14, further diagnostic steps should be undertaken in order to exclude abnormalities of sexual differentiation. The most significant symptom for the latter is primary amenorrhea.

Adolescent↗
PubMed1993

Rabies and borna disease. A comparative pathogenetic study of two neurovirulent agents.

BACKGROUND: Rabies and Borna disease viruses have been regarded as classical neurotropic agents. Many pathogenetic similarities are shared by these two negative strand RNA viruses. In view of recently gained data on the virology and pathology of these two diseases, and up-to-date comparative pathogenetic study seems to be justified. EXPERIMENTAL DESIGN: This study is based on a survey of experimental and natural infections of laboratory animals and natural hosts. The morphologic damage to the nervous system has been evaluated by light and electron microscopy, with special emphasis on immunocytochemical methods. RESULTS: This comparative study disclosed that both viruses are transported inside axons, pass synapses and propagate along neuronal networks. At the sites of synaptic transfer, full virus particles can never be detected in the early phase of rabies virus infection; in Borna disease virus (BDV) infection, virus particles cannot be found in any phase of disease progression. Thus, a major difference exists between the two agents insofar as rabies virus is morphologically well characterized, whereas BDV has never been visualized in tissue sections. Furthermore, rabies virus infects only neurons, whereas BDV also infects glial cells. The host range and the scale of infection of extraneural tissues by both agents is extremely similar. CONCLUSIONS: These observations allow us to postulate that the synaptic transfer of both viruses likely ensures in the form of bare nucleocapsids (ribonucleoprotein-transcriptase complexes). While in the later phases of replication complete rabies virions are regularly assembled, BDV propagates within the central nervous system in an incomplete form, so that it remains morphologically imperceptible. Thus, BDV may appear in a complete, enveloped form only when exiting the host organism. The dissemination patterns of the two agents may be influenced by specific affinities to neurotransmitter receptor sites. It remains unresolved, why BDV readily infects non-neuronal central nervous system cells, while rabies virus remains restricted to neuronal elements.

Animals↗
PubMed1992

Borna disease virus, a negative-strand RNA virus, transcribes in the nucleus of infected cells.

Borna disease virus, an unclassified infectious agent, causes immune-mediated neurologic disease in a wide variety of animal hosts and may be involved in pathogenesis of selected neuropsychiatric diseases in man. Initial reports suggested that Borna disease virus is a single-stranded RNA virus. We describe here a method for isolation of viral particles that has allowed definitive identification of the genome as containing a negative-polarity RNA. Further, we show that the viral mRNAs are transcribed in the nucleus.

Borna disease virus↗
PubMed1992

Human infections with Borna disease virus: seroprevalence in patients with chronic diseases and healthy individuals.

Borna disease virus (BDV) is as yet an unclassified infectious agent which causes a neurologic disease in horses and sheep and is transmissible to other animal species. Human sera were tested for BDV-specific antibodies by immunofluorescence and immunoprecipitation. The sera were collected from three thousand subjects in Europe, the USA, and Africa classified by clinical syndromes/infectious diseases, and from healthy controls. In all three continents, positive serum samples were detected which recognized the major BDV antigen of 38/40 KD present in the nuclei of infected cells. In contrast to 2% of seropositives among the normal population, significantly higher prevalences (13-14%) were present among patients with chronic progressive diseases of the brain and the immune system. In children, antibody frequencies were two to four times higher than in adults. The results suggest a latent infection with BDV in humans leading to low antigen expression in healthy subjects and frequent reactivation events in chronically ill patients.

Adult↗
PubMed1992

Antarctic seals carry antibodies against seal herpesvirus.

Weddell seals in the Antarctica had high neutralizing antibody titres to seal- and feline herpesvirus and none against phocine distemper virus. Crab-eater seals were free of antibodies. This suggests an evolutionary wide spread of seal herpesvirus.

Animals↗
PubMed1992

Do chemo- and radiotherapy affect the DNA repair ability of lymphocytes?

The DNA repair ability of unstimulated lymphocytes damaged by ultraviolet irradiation was measured in a group of 15 breast cancer patients before surgery, and 3 to 5 years later a) after surgery alone (n = 6), or b) after surgery with additional chemo- and/or radiotherapy (n = 9). In group a) 3 out of 6 patients had reduced repair before and 2 out of 6 after surgery. In the group b) 4 out of 9 patients had reduced repair before surgery, and 9 out of 9 after surgery plus chemo/radiotherapy. These results confirm our previous finding that chemo/radiotherapy influences DNA repair negatively. Because of the known association between reduced DNA repair and cancer occurrence, this could increase the risk of a secondary tumour.

Breast Neoplasms↗
PubMed1992

Interleukin-2 receptor positive cells in human decidua during the first trimester of pregnancy and their association with macrophages.

Maternal immune rejection of the fetus could sometimes be the cause of unexplained recurrent spontaneous abortion. Components of the T cell-mediated immunity were investigated in the first trimester of pregnancy in women having spontaneous abortion and compared to those with normal pregnancy having a termination on social grounds. Interleukin 2 (IL-2) had no proliferative effect on the trophoblasts of chorionic villi and there were also no IL-2 receptors in these cells. However IL-2 receptor positive cells were found in the decidua in 7 out of 24 women with normal pregnancy and in 12 out of 18 with spontaneous abortion. A high density of macrophages showed an association with IL-2 receptors in both groups. There were no differences with respect to T-cytotoxic cells and T-helper cells in cases of normal pregnancy (with and without IL-2 receptor positive cells), whereas in women having spontaneous abortion we found lower densities of T-helper and T-cytotoxic cells in those without IL-2 receptors than in those with IL-2 receptors.

Abortion, Induced↗
PubMed1992

Borna disease virus-specific antigens. II. The soluble antigen is a protein complex.

Borna disease virus-specific soluble antigen from persistently infected rat brains was purified to homogeneity using preparative sodium dodecyl sulphate-polyacrylamide gel electrophoresis. The soluble antigen is a complex of three proteins with apparent molecular weights of 35 kDa, 38 kDa and 24 kDa. The 35/38 kDa antigen double band was separated into its two components. The 24 kDa protein has no common epitopes with the 35/38 kDa protein.

Animals↗
PubMed1992

Herpesvirus infections in seals: a summary of present knowledge.

This review summarises the occurrence of herpesvirus infections in pinnipeds and data from investigations carried out by the authors. These data demonstrate that herpesvirus isolates collected from harbour seals (Phoca vitulina Linnaeus, 1758) during the 1988 seal epidemic were almost indistinguishable from feline herpesvirus 1 and that Antarctic Weddell's seals (Leptonychotes weddelli Lesson, 1826) carry antibodies against seal herpesvirus from the north-western Europe seal epidemic. The significance of herpesvirus infections in seals is discussed.

Animals↗
PubMed1992

Axonal and transsynaptic (transneuronal) spread of Herpesvirus simiae (B virus) in experimentally infected mice.

In order to study the pathogenesis of B virus infection of the nervous system, newborn and young mice were inoculated by four different routes: 1. Intramuscular (i.m.) in the forelimb; 2. I.m. in the hindlimb; 3. Subcutaneous (s.c.) in the abdominal wall; 4. Intraperitoneal (i.p.). Spread of virus was followed by immunohistochemical demonstration of viral antigen in tissue sections of the peripheral and central nervous system. Three distinct patterns emerged: 1. After i.m. limb inoculations, virus progressed along the ipsilateral dorsal column, the bilateral spinothalamic and bilateral spinoreticular systems and along central autonomic pathways. 2. After s.c. inoculation, the dorsal column was spared, otherwise the spread was similar to that following i.m. inoculations. 3. After i.p. inoculation, virus spread in the spinal cord bilaterally, mainly along spinothalamic and central autonomic pathways. The peripheral motoneurons were conspicuously spared, even in the i.m. inoculation mode. In the brain stem, B virus antigen appeared bilaterally, at multiple sites. In the cerebrum, virus infected cells appeared first in the thalamus, hypothalamus and the motor cortex. The mode of spread from spinal levels was mainly orthograde along the ascending systems (dorsal columns, spinothalamic, spinoreticular tracts), but also retrograde along descending systems (pyramidal tract, central autonomic pathways). Oligosynaptic systems transmitted virus more quickly than the polysynaptic ones. In the involvement of various neuronal systems in virus spread, a certain selectivity, sparing the peripheral motoneuron and the cerebellar systems, could be assessed.

Aging↗
PubMed1991

Predictive value of interleukin-6 and neopterin in patients with multiple myeloma.

Concentrations of interleukin-6 and neopterin were measured in sera from 44 patients with multiple myeloma. To judge the relative prognostic value of these analyses, other clinical and laboratory variables were concomitantly determined. The patients were followed up to 9 years, and the abilities of all variables to predict outcome were assessed. Both neopterin (P = 0.0008) and interleukin-6 (P = 0.033) were significantly higher in patients with higher stages of the disease. The correlation between interleukin-6 and neopterin was weak but significant (Spearman's rank correlation coefficient, 0.38; P = 0.019). By univariate survival analysis using the product-limit approach, both neopterin (P = 0.0001) and interleukin-6 (P = 0.025) were identified as significant predictors of survival. Multivariate survival analyses by the proportional hazards technique demonstrated that either stage and neopterin or neopterin and interleukin-6 are useful combinations of predictor variables. Thus, interleukin-6, which is supposed to influence progression of multiple myeloma in an autocrine or paracrine manner, failed to contribute to prediction if stage was included in a model. In contrast, neopterin remained significant in all multivariate models.

Aged↗
PubMed1991

Subspecialization in gynecology and obstetrics: advantages and disadvantages.

To discuss the problem of subspecialization in our discipline is presently very popular. Whether or not a complete separation into the three subdisciplines: (1) materno-fetal medicine - obstetrics (2) surgical gynecology - gynecologic oncology (3) gynecologic endocrinology - reproductive medicine is recommended remains unclear in most of the statements. Some describe forms of only a supplementary postgraduate education, a kind of prolongation of the basic gynecologic and obstetrical training concentrated on one of the three main fields. The complete separation, i.e., in obstetrical medicine, reproductive medicine, gynecologic pelvic surgery, has the advantage of a more effective concentration on each of the respective subdisciplines in clinical work and in research. On the other hand, the separation will certainly produce several disadvantages: (a) What is inbetween the subdisciplines will be difficult to integrate. (b) The principle of the gynecologist functioning as a primary health care physician for women will be weakened, i.e., his competence for family-planning, pregnancy and delivery of normal cases, for cancer screening of genital and breast tumors, for disorders of the cycle, for pelvic inflammatory diseases and for the care of postmenopausal women will be less integral. (c) The lectures will be more than at present split or overloaded with detailed facts. (d) The need of general gynecologic care - as well cost-effective as widely available - will less frequently be met than now. (e) The opportunities for younger colleagues to settle with an office of their own will be restricted. The disadvantages outweigh the advantages.(ABSTRACT TRUNCATED AT 250 WORDS)

Education, Medical, Graduate↗