[HPV-associated carcinomas of the female genital tract. Molecular mechanisms of development]. / HPV-assoziiertes Karzinom des weiblichen Genitaltrakts. Molekulare Mechanismen der Entstehung.

Infections with human papillomaviruses (HPV) are a common occurrence in both men and women. In contrast HPV-associated neoplasias are relatively rare and occur only in certain areas of the body. The virus has obviously developed efficient mechanisms for its persistence without inducing too much damage to the host. The formation of neoplasia seems to be more an exception. Epigenetic mechanisms play an important role in the regulation of viral gene expression. Investigations have indicated that exactly the transition from the permissive infection stage to a transformation stage, where neoplastic alterations can occur due to expression of the viral oncogenes, is associated with certain methylation patterns of the viral genome which promote the expression of the oncogenes E6 and E7. The transforming stage is seen as the actual carcinogenic event and can be immunohistochemically detected by the biomarker p16(INK4a).

Prognostic impact of EBV-related LMP-1, histologic type, and environmental factors in nasopharyngeal carcinoma in a German population.

INTRODUCTION: This retrospective study addressed the possible involvement of latent Epstein-Barr virus (EBV) infection, in particular LMP-1 expression, and further exogenous factors, i.e. tobacco, alcohol and occupational hazardous substances, in nasopharyngeal carcinoma (NPC) in a German population. PATIENTS AND METHODS: From 1980 to 2000, 44 patients suffering from histologically confirmed NPC were entered into the study. 33 specimens were available for immunostaining (IHC) to analyze LMP-1 expression. Information about environmental exposures were obtained employing a detailed standardized questionnaire. RESULTS: Outcome of patients with squamous cell NPC (SC-NPC) was significant worse than that of those with non-keratinizing NPC (NK-NPC). Age and tumor size correlated with response to therapy. The group with negative conventional LMP-1 staining showed better overall survival after 5 years compared to the group with positive or marginally positive LMP-1 detection (not significant). Nevertheless, after staining by tyramid-augmented IHC (TSA-IHC), nearly all specimens with negative LMP-1-staining in conventional IHC were found to be clearly positive. All patients with SC-NPC were smokers. The distribution of smokers and non-smokers in the group of NK-NPC was balanced. Comparable to the tobacco observation, there was also a correlation between high alcohol consumption and SC-NPC. CONCLUSION: Prognosis of NPC is mainly dependent on histologic type. Prognostic impact of LMP-1 is still unclear since LMP-1 was detected in all specimens using TSA-IHC. Therefore, TSA-IHC-LMP-1 detection might be interesting for diagnostic specification and development of new therapeutic strategies in NPC.

[Malignant atrophic papulosis (Köhlmeier-Degos disease). Failure to respond to interferon alpha-2a, pentoxifylline and aspirin]. / Maligne atrophische Papulose (Morbus Köhlmeier-Degos) Kein Ansprechen auf Interferon alpha-2a, Pentoxifyllin und Azetylsalizylsäure.

A 45 year old female patient presented with the cutaneous manifestations of malignant atrophic papulosis (Köhlmeier-Degos disease) for two years. The typical papules with central porcelain-white atrophy correspond histologically to wedge-shaped necrosis of the connective tissue due to thrombotic occlusion of small vessels in the corium. The pathogenesis of malignant atrophic papulosis and effective treatment modalities are unknown. A slow virus infection has been suggested by some authors. Therefore, we attempted an immune therapy with interferon alpha-2a over a period of 11 months, but failed to cause a significant effect on the appearance and progression of the skin lesions. Furthermore, we could not confirm the effectiveness of a recently reported treatment modality with pentoxifylline and aspirin administered to our patient over a period of 5 months.

Sporadic ALS/MND: a global neurodegeneration with retroviral involvement?

Sporadic amyotrophic lateral sclerosis may be an aetiologically heterogenous disease. We confirmed elevated circulating IgG immune complexes, and altered IgG seroreactivities against human retroviral antigens (HIV-2 and HTLV immunoblots) in overlapping subgroups of patients. Together with preliminary findings of a positive polymerase chain reactivity for human T-lymphotropic virus (HTLV.tax/rex) in blood leukocytes of 5 out of 14 sALS patients, we interpret this as evidence for a retroviral involvement in this relentlessly progressive, often asymmetrically spreading neurodegeneration. The possibility of a secondary phenomenon seems unlikely, yet cannot be completely ruled out.

[The induction by the influenza virus A/H1N1 (serovariant Hsw1N1) and its glycoproteins of congenital pathology in mice]. / Induktsiia virusom grippa A/H1N1 *serovariant Hsw1N1) i ego glikoproteidami vrozhdennoi patologii u myshei.

Influenza A/H1N1 (serovariant Hsw1N1) virus, a sum of isolated glycoproteins, separately neuraminidase "heads", inoculated into white random-bred female mice, induced in some of the offsprings the pathology clinically and pathomorphologically similar to previously described slow virus infection. At the same time, the pathology in the offsprings caused by the antigenic virus variant under study was characterized by complete absence of fur and more dynamic progress of the disease. It is quite obvious that glycoproteins, particularly neuraminidase, are the molecular biological basis of dystrophic and degenerative changes in the organs of baby mice due to desialization and increased fluidity of capillary endothelium membranes and, possibly, CNS and other organ cells.

[The persistence of the causative agent of amyotrophic leukospongiosis and the astrocyte reaction in monolayer cultures of brain cells]. / Persistentsiia vozbuditelia amiotroficheskogo leikospongioza i reaktsiia astrotsitov v monosloinykh kul'turakh kletok mozga.

The amyotrophic leukospongiosis (AL) agent which is considered to be an unconventional virus was shown to replicate and amplify in non-neuronal monolayer brain cell cultures. The AL agent persistence was accompanied by complicated morphofunctional changes in astrocytes, some of them developing a specific cytodystrophic process. Phagocytosis in the infected astrocytes came to its end. The dose-dependent effect and selective sensitivity of these cells to the cytodestructive activity of AL was demonstrated. Astrocytes are regarded to be target cells serving as a reservoir for agent amplification.

[Cellular transformation in an MDCK culture caused by the agent of amyotrophic leukospongiosis]. / Obuslovlennaia agentom amiotroficheskogo leikospongioza transformatsiia kletok v kul'ture MDCK.

The possibility of infecting epithelioid MDCK cell culture with the agent of amyotrophic leukospongiosis (AL) was shown. Various morphofunctional changes were observed in the infected cells. In the first subpassage, the saturation density and yields of cells increased, while their mitotic activity decreased and adhesive properties changed. In the second subpassage, the cell morphology and monolayer architectonics changed, the cells losing the ability to form a confluent monolayer. The infected cultures died in further subpassages. Clinical signs of the disease and morphological changes in the CNS typical of AL were observed in the animals infected with a homogenate of cells and culture fluid from the AL-agent-infected cultures.

Immunogold light and electron microscopic detection of amyloid plaques in transmissible spongiform encephalopathies.

The antigenicity of the 'prion' protein amyloid fibrils was shown to be preserved after glutaraldehyde/OsO4 fixation in uranyl acetate-stained brain tissue blocks from patients with Gerstmann-Sträussler syndrome (GSS) and from mice infected with Creutzfeldt-Jakob disease (CJD). Amyloid plaques were demonstrated by light microscopy in immunogold silver-intensified semithin sections. Under the electron microscope, the amyloid fibrils were labelled in immunogold-reacted ultrathin sections using an antiserum prepared against GSS amyloid plaque cores and mouse amyloid fibrils respectively. The influence of various oxidizing agents (hydrogen peroxide, sodium metaperiodate) on the tissue preservation and the immunohistochemical detection was tested.

[Juvenile spongiform encephalopathy with unusual pathomorphologic findings]. / Encefalopatia spongiforme giovanile con insoliti reperti patomorfologici.

A 27-year-old man presented disturbances of gait and language, quickly followed by intellectual deterioration, tetraplegia, anarthria and myoclonus. Histological examination of a cerebral biopsy showed not only cortical changes consistent with the diagnosis of Creutzfeldt-Jakob disease, but also many amyloid-plaques with variable morphology. The diagnostic interpretation of the case particularly as to concern his relationship to s.c. Gerstmann-Strüssler syndrome is discussed.

Potential involvement of retroviral elements in human dementias.

Creutzfeldt-Jakob disease (CJD) is a dementia of humans caused by a class of infectious agents with several biological properties similar to those of conventional viruses. The molecular nature of this group of agents is enigmatic, for neither an agent-specific nucleic acid nor a non-host protein has yet been identified. Recent transmissions of familial CJD dementias to rodents suggest that this class of agent can be integrated into the germline. Furthermore, tissue culture studies indicate that CJD causes transformation of cells in a manner reminiscent of slowly oncogenic retroviruses. Currently characterized retroviral-like elements include many forms that do not have 'typical' retroviral ultrastructural morphology; several forms are also known to be resistant to various types of standard physicochemical inactivation. We suggest that CJD agents are either constituted by retroviral-like nucleic acids or interact with endogenous retroviral sequences to elicit a slowly progressive disease of the central nervous system. Several overlapping properties between infectious CJD and 'non-infectious' dementias, such as Alzheimer's disease, implicate potential common pathogenic mechanisms.

Lectin histochemistry of plaques and tangles in Alzheimer's disease.

Biotinyl derivatives of several lectins and avidin-horseradish peroxidase were used to study the localization of glycoconjugates in amyloid plaques and in neuritic tangles in brains of patients with Alzheimer's disease (AD), Downs syndrome (DS) and Gerstmann-Sträussler syndrome (GSS). The lectins tested recognize the following residues: beta-D-galactosyl [Ricinus communis agglutinin 120, (RCA-1) and peanut agglutinin, (PNA)]; alpha-D-galactosyl [Griffonia simplicifolia agglutinin (GSA)]; alpha-D-mannosyl greater than alpha-D-glucosyl [concanavalin A (Con A) and Lens culinaris agglutinin (LcH)]; N-acetyl- and N-glycolyl-neuraminic acid [Limax flavus agglutinin (LFA) and Limulus polyphemus agglutinin (LPA)]; N-acetyl-glucosaminyl and sialyl [wheat germ agglutinin (WGA)]; N-acetyl-D-galactosaminyl [Helix pomatia agglutinin (HPA) and Dolichos biflorus agglutinin (DBA)] and alpha-L-fucosyl [Ulex europeus agglutinin (UEA-1)]. The majority of lectins listed above bind preferentially to the peripheral area of AD plaques, whereas in plaques of DS they are mainly bound to central amyloid core. In neurofibrillary tangles of AD brains only residues recognized by WGA and HPA or DBA were found, whereas in DS brains, in addition to above mentioned, beta-D-galactose (RCA-1) and sialic acid (LFA) were also present. In brain microblood vessels the strongest reaction in endothelia appeared with UEA-1 and RCA-1, indicating the abundance of alpha-L-fucosyl and beta-D-galactosyl residues. In AD brains deposits of amyloid were noted in the wall of some blood vessels, where monosaccharide residues recognized by RCA-1, GSA, UEA and WGA but not by Con A and LFA were present. However, our studies of some organs (liver, kidney, heart and testes) of patients with generalized amyloidosis revealed a lack of these sugar residues. It indicates, that the composition of amyloid present in brains of AD is different to that in other organs in generalized amyloidosis.

Implications of the neuropathology of HIV encephalitis for the pathogenesis of Alzheimer disease.

The strong familial association of Alzheimer disease (AD), the difficulty in transmitting the disease to animals, the mapping of the amyloid gene to human chromosome 21, and the non-inflammatory neuropathology have all been considered evidence against a viral etiology for this disease. However, unconventional slow viral infections share some of these traits with AD and yet they are caused by retroviruses or suspected viruses. The recent discovery of 2 human retroviruses causing central nervous system pathology similar to spongiform encephalopathies should prompt renewed search for retroviral causes of human neurodegenerative diseases.

Gerstmann-Sträussler-Scheinker disease with coincidental familial onset.

A family with Gerstmann-Sträussler-Scheinker disease had coincidental clinical onset in three members of two generations, a phenomenon suggesting a common source of a transmissible agent. A regular dietary supplement in this family was home-bred rabbit. The clinical picture, although generally similar to that in previous accounts, included the unusual findings of visual loss (one patient) and sensory loss (one patient), and dementia was not apparent until late in the illness in two patients. Pathological examination of a cerebellar cortical biopsy specimen from one patient and postmortem tissue from two patients revealed multicentric amyloid plaques located in cerebral and cerebellar cortex, basal ganglia, and white matter with degeneration of corticospinal, dorsal spinocerebellar, dentatorubral, and geniculocalcarine tracts and dorsal columns. Spongiform change was focal and confined to the superficial cerebral cortical layers.

Experimental infection of sheep by caprine arthritis-encephalitis virus and goats by progressive pneumonia virus.

The lentiviruses, caprine arthritis-encephalitis virus (CAEV) and progressive pneumonia virus (PPV) of sheep, cause major diseases in their respective hosts; however, the infectivity of these viruses for closely related species has not been determined. Experiments were conducted to determine whether CAEV would infect sheep and whether PPV would infect goats. Upon inoculation with CAEV, lambs developed a nonsuppurative arthritis and antibody to CAEV, and the virus was isolated up to 4 months later. Exposure of 3 lambs to CAEV-infected adult goats did not lead to demonstrable infection after 18 months. Young goats inoculated with PPV replicated the virus and developed arthritis and antiviral antibody. These results demonstrate that these distinctly different lentiviruses may infect and cause diseases in species other than their accustomed host. Presently used techniques may not be effective in differentiating which lentivirus is responsible for infection of sheep and goats. Our results also indicate that mixing sheep and goats may adversely influence attempts to eradicate lentiviruses from these species.