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Through the use of immune sera prepared from chickens, the crossserological study of 22 prototypes of bovine enteroviruses isolated in different parts of the world, allowed us to identify two serological groups each of which contained 11 viruses. The viruses of the first group are closely antigenically related although they can be distinguished in 'broad' and 'specific' variants, the latter showing asymmetrical serological relationships with one or more viruses of the same group. The viruses of the second group show antigenic relationships of a lower degree and may be divided into subgroups on the basis of their main antigenic correlations. The study of hemagglutinating properties toward rhesus monkey erythrocytes demonstrated that such properties are constantly present in viruses of group 1 and are lacking in viruses of group 2. On the basis of those data we elaborated a classification outline that proved to be useful in identifying 18 more strains of bovine enteroviruses in a satisfactory manner. [ABSTRACT FROM AUTHOR]

Protein misfolding and aggregation are the common mechanisms in a variety of aggregation-dependent diseases. The compromised proteins often assemble into toxic, accumulating amyloid-like structures of various lengths and their toxicity can also be transferred both in vivo and in vitro a prion-like behavior. The characterization of protein interactions, degradation and conformational dynamics in biological systems still represents an analytical challenge in the prion-like protein comprehension. In our work, we investigated the nature of a transferable cytotoxic agent, presumably a misfolded protein, through the coupling of a multi-detector, non-destructive separation platform based on hollow-fiber flow field-flow fractionation with imaging and downstream in vitro tests. After purification with ion exchange chromatography, the transferable cytotoxic agentwas analyzed with Atomic Force Microscopy and statistical analysis, showing that the concentration of protein dimers and low n-oligomer forms was higher in the cytotoxic sample than in the control preparation. To assess whether the presence of these species was the actual toxic and/or self-propagating factor, we employed HF5 fractionation, with UV and Multi-Angle Light Scattering detection, to define proteins molar mass distribution and abundance, and fractionate the sample into size-homogeneous fractions. These fractions were then tested individually in vitro to investigate the direct correlation with cytotoxicity. Only the later-eluted fraction, which contains high-molar mass aggregates, proved to be toxic onto cell cultures. Moreover, it was observed that the selective transfer of toxicity also occurs for one lower-mass fraction, suggesting that two different mechanisms, acute and later induced toxicity, are in place. These results strongly encourage the efficacy of this platform to enable the identification of protein toxicants., (Copyright © 2019 Elsevier B.V. All rights reserved.)

We demonstrated the presence of an in vitro transmissible cytotoxic agent (TCA) in the cerebrospinal fluid (CSF) of patients with different acute neurological diseases. The nature of this agent is still a matter of study since repeated attempts have failed to identify it as a conventional infectious agent. Here, we describe the mechanisms through which TCA affects human astrocytes, demonstrating: a late apoptotic process, mediated by caspases 9 and 3 activation, involving the Bcl2-Bak-axis; an early and late p38 MAPK activation; an interference with the IL-8 and MCP-1 secretory response. These in vitro data provide initial evidence of TCA involvement as a pro-apoptotic and pro-inflammatory signal, directly affecting astrocytic behavior. The implications of these findings in certain neurological diseases will be discussed.

A transmissible cytotoxic agent thought to be associated with one or more misfolded protein(s) was found in several cerebrospinal fluid (CSF) samples from neurological patients. Since some experiments carried out to identify this unusual infectious factor showed the block of its propagation by rabbit gammaglobulins (IgGs), the search for such an activity by human IgGs was programmed. Neutralizing assays carried out using human sera as IgGs source showed a blocking property displayed by: twenty serum samples from as many patients with a diagnosis of acute infection, two of ten sera from healthy subjects and four serum samples from patients with lupus erythematous (SLE). When neutralizing sera were tested on cell cultures in immunofluorescence assays for the serum ability to label specific protein( s), similar fluorescent pictures resulted in treated and control cells. On the other hand, the SLE serum samples disclosed a granulosity of the nuclear material of cytotoxic cells in accordance with the DNA apoptotic laddering reported in previous papers. Oxidative disorders, as suggested by the immunoblotting analysis of the antioxidant enzymes Mn-superoxide dismutase (SOD2) and heme-oxygenase 1 (HO-1), point to an alteration of the oxidative pathway among the causes of the DNA damage induced by the cytotoxic transmissible agent under study.

Positive results were attained when human peripheral blood lymphocytes (PBLs) were investigated for their ability to propagate a transmissible cytotoxic activity (TCA) isolated on VERO cell cultures from a sample of cerebrospinal fluid (CSF) drawn from a woman with ischemic brain injury. In consideration of this finding it can be assumed that "in vivo" blood lymphocytes contributed to give rise to the TCA detected "in vitro" in the CSF inoculum.

We report an unusual case of documented Bartonella henselae genotype I from hepatic tissue in an Italian immunocompetent girl presenting with erythema nodosum and hepatic granulomata. Polymerase chain reaction (PCR) was performed on biopsied liver sample to confirm the etiologic role of B. henselae and to identify the genetic variant of this organism. A PCR on the same liver biopsy for parvovirus B19 was also positive, but the clinical meaning of this was not clear.

A case of primary infection by human herpesvirus 6 (HHV-6) variant A in a 54-year-old woman, which occurred at the same time as the onset of encephalomyelitis, is reported. The correlation between the two events is discussed. It is speculated that, during the early phase of the infection, the HHV-6 spread to the central nervous system and triggered a pathogenic process that initially developed without symptoms. When the neurological disorders appeared, HHV-6 had already established a latent state: only the virus carried by infected blood cells was detected in the cerebrospinal fluid.

When inoculated into cell cultures to search for cytopathic viruses, six out of 384 cerebrospinal fluid (CSF) samples from patients with different neurological disorders proved to have a transmissible cytotoxic activity (TCA) not correlated to a conventional infectious agents. Properties shown by a TCA previously detected in the CSF sample of a patient with brain ischemia (Portolani et al., 2005) were shared by each of the newly isolated TCAs. We conclude that independently of the neurological clinical picture shown by the patient, the TCA detected in the CSF samples under study could have the same origin.

An HHV-6 variant A infection is described in a 75 year-old man in association with meningoencephalitis identified at autopsy. The patient presented with fever and anorexia, then he developed altered consciousness, motor weakness, progressive lethargy, and coma, and died 21 days after hospital admission. Histopathological examination showed perivascular lymphocytic infiltrates in the central nervous system (CNS). Serum and cerebral spinal fluid (CSF) samples drawn from the patient were tested for viruses by a nested polymerase chain reaction (nPCR). HHV-6 primers A and C [Aubin et al., 1991: J Clin Microb 29: 367-372] and HS6AE and HS6AF from [Dewhurst et al. (1993): J Clin Microb 31: 416-418] disclosed a 750 bp genomic product of HHV-6 in both types of biological samples. Restricted site analysis showed that the HHV-6 DNA amplified belonged to the variant A of the virus. Short sequences of HHV-6 DNA could also be detected in the DNA extracted from formalin-fixed, paraffin-embedded sections of CNS tissues by use of one (GM5 and GM6) of three pairs of HHV-6 primers that were selected. Immunohistochemical examination of brain sections, employing a specific monoclonal antibody directed against the HHV-6 gp 102 protein, detected the viral antigen in neurons and glial cells., ((c) 2005 Wiley-Liss, Inc.)

We investigated a transmissible cytotoxicity isolated in VERO cell cultures from a sample of cerebrospinal fluid (CSF) drawn from a woman with ischemic brain injury. Amorphous aggregates formed by subunities of approximately 11 nm of diameter were detected in ultracentrifugates from partially purified cytotoxic cell preparations in the absence of virion-like particles which might justify the trasmissibility of this cytotoxic activity. Results of chemico-physical studies provided indications on the presence in the CSF of two protease-resistant acidic glycoproteins of about 39 and 27 kDa, respectively. The conformational change of a proteinic molecule may associate with particular properties such as tendency to aggregation, resistance to proteolysis, cytotoxicity. Considering that these same properties are shared by proteins present in the CSF sample under study, a hypothesis to pursue is that the CSF inoculum we isolated contained misfolded proteins formed in vivo following the ischemic injury of brain tissue. As far as the in vitro transmissibility of the cytotoxic activity, this could take place following the reproduction of the alterations of those proteins, independently of the original cause(s) which have fostered their formation in vivo.

Ameloblastomas are epithelial tumors of odontogenic origin, biologically characterized by local recurrence. Among different etiologic factors, HPV infection has been recently postulated to be somehow involved in ameloblastoma etiopathogenesis. To address this issue, we studied 18 ameloblastomas by means of immunohistochemistry, in situ hybridization (conventional and amplified), polymerase chain reaction and nested-polymerase chain reaction analyses using laser capture microdissection in order to detect the occurrence of HPV in this setting. No evidence of HPV infection was detected by morphological examination, immunohistochemistry, in situ hybridization and conventional polymerase chain reaction, while nested-polymerase chain reaction showed a weak positive band in two cases. However, the subsequent restriction enzyme analysis carried out from the nested-polymerase chain reaction amplification products of these two samples excluded the presence of HPV subtypes 16, 18, 31, 33, 35, 52, and 58. The search for HPV 6 and 11 in the same specimens was also negative. In conclusion, our data do not support an etiopathogenetic evidence for HPV in ameloblastoma.

In the years 1999-2001, 868 samples of cerebrospinal fluid (CSF) from as many patients with acute neurological manifestations of suspected viral origin were analysed for the presence of viruses at the Centre for the Diagnosis of Viral Diseases of the University of Modena and Reggio Emilia. Neurological patients included 788 immunocompetent subjects and 80 patients with impaired immunity due to human immunodeficiency virus (HIV) seropositivity. Of the CSF samples, 125 (15.8%) were positive for one or more viruses among the immunocompetent patients, whereas 33 (41.1%) were positive among the HIV cohort. DNA and RNA viruses were detected in the first group of CSF samples whereas only DNA viruses were found in the second group. In immunocompetent patients the frequency of enteroviruses prevailed over that of other RNA virus families (p = 0.001) and that of herpesviruses over the frequency of other DNA virus families (p = 0.001). Among herpesvirus members, the Epstein-Barr gamma-herpesvirus prevailed on alpha-herpesviruses in each of the two groups of patients (p = 0.05 in the immunocompetent group and p = 0.006 in HIV-positive patients). The clinical relevance both of this virus and of beta-herpesviruses as a cause of neurological disorders is discussed.

A case of non-specific febrile illness by Coxsackievirus A 16 (CA 16) in a 6-day-old newborn whose mother had developed hand, foot and mouth disease manifestations 2 days after delivery is reported. Notwithstanding the concurrence of negative circumstances like the presence of the enterovirus genome in the cerebrospinal fluid, absence of type specific neutralizing antibody and a few days of life, the newborn recovered 3 days after the onset of fever. This case, also characterized by the absence of mucosal and cutaneous erythematous manifestations typical of CA16 infection, draws attention to the possibility that non-specific febrile illness in newborns usually suspected of bacterial origin may have an enteroviral cause.

Previous infection, both of bacterial and viral origin, is reported to represent an independent risk factor for ischemic stroke in children and young adults. The authors describe the case of an immunocompetent young woman who developed a middle cerebral artery thrombosis and stroke in course of a recurrence of human parvovirus B19 (PVB19) infection. A previously healthy 25-year-old woman developed right ataxic hemiparesis, 5 days after the onset of a flulike syndrome. Magnetic resonance imaging of the brain revealed acute multiple left frontal-parietal ischemic lesions. Conventional and magnetic resonance angiograms revealed a stenosis in the left middle cerebral artery. Nested polymerase chain reaction detected PVB19-specific DNA sequences in the cerebrospinal fluid and blood, and serology showed high titers of high avidity immunoglobulin G against PVB19. After 10 days, the patient's recovery was nearly complete. One month later, PVB19 disappeared from the serum, whereas it persisted in the peripheral blood mononuclear cells. This case report suggests that PVB19 infection may play a trigger role in the development of ischemic stroke, and that it should be considered in the screening of infectious risk factors for cerebrovascular diseases in young adults.

A 7-year-old male presented sudden-onset left hemiparesis, left-sided paresthesia, central paralysis of the left VII cranial nerve, and subsequent headache. Magnetic resonance scans were obtained 24 hours after admission. T(2)-weighted images disclosed hyperintensities located mainly in the posterior portion of the lenticular nucleus and in the head and body of the right caudate nucleus. A diagnosis of ischaemic stroke was made on the basis of neuroradiologic findings. Laboratory tests undertaken to establish the cause of stroke revealed parvovirus B19 infection preceding the neurologic abnormalities. In the absence of other known risk factors for stroke the possibility of parvovirus B19's being correlated with stroke onset is discussed.

When a six year-old immunocompetent child affected by encephalitis was subjected to virological studies, human herpesvirus 6 variant B2 resulted to be the cause of illness. Laboratory diagnosis based on the finding of human herpesvirus 6 genome in the cerebrospinal fluid of the patient both at the beginning of the disease and on the occasion of a relapse which occurred forty days after the patient's hospital discharge. The presence of high-avidity IgG to human herpesvirus 6 detected in the patient's serum at the time of the first hospital admission proved that he had suffered from a past infection by human herpesvirus 6. In the consequence of this, the human herpesvirus 6 DNA finding in the patient's cerebrospinal fluid was to ascribed to virus reactivation. In the light of virological and serological results, the clinical case described underlines the ability of human herpesvirus 6 to cause neurological disorders not only during primary infections but also during infections supported by rescued virus.

We report nine cases of clinical manifestations by Toscana virus (TOSV) diagnosed at the Centre for the Diagnosis of Viral Diseases of the University of Modena and Reggio Emilia, in the inhabitants of Modena province (Emilia Romagna region), in the triennium 1999-2001. TOSV was involved in six cases of meningitis, two of meningoencephalitis and one case of febrile erythema without meningeal manifestations. Six TOSV-infected patients had stayed for a few days in a different area of the Tuscany region before the onset of clinical manifestations so, only three cases of infections by TOSV had an autochthonous origin.

Keshan disease is a cardiomyopathy of unknown origin reported in some areas of China. Because of epidemiologic features, this disease was ascribed to an infectious agent, likely a Coxsackie virus, but it has also been thought to depend on selenium deficiency, mainly because selenite is effective in its prophylaxis. We examined the hypothesis that pharmacological activity of selenite on Coxsackie virus growth was associated with prevention of Keshan disease. We studied the antiviral effects of three selenium compounds on Coxsackie virus B5 replication: five microM selenite reduced viral replication, whilst 10 microM selenate and selenomethionine did not exhibit any antiviral activity. The inhibitory activity of selenite on viral replication was due to its toxicity following its interaction with thiols, as that activity could be blocked by dithiothreitol, a sulfhydryl-protecting agent known to reverse several toxic effect of selenite. Zinc, another inhibitor of selenite toxicity, also counteracted the antiviral effect of selenite. The selenium compounds showed only limited activity against herpes simplex 1 virus and IHD strain of vaccinia virus. A direct inhibitory effect of selenite on Coxsackie virus replication might explain the efficacy demonstrated by this compound in the prophylaxis of Keshan disease.

This note reports the finding of human herpes virus 8 DNA in the cerebrospinal fluid of a woman with sensory impairment correlated with a basal disease suspected to be multiple sclerosis.

A fatal case is reported of encephalitis in an 85-year-old man caused by the human herpesvirus 6 variant A. The virological diagnosis was based on the findings of the virus variant genomic sequences both in the cerebrospinal fluid and serum of the patient. Moreover, virus replication in nervous tissue was suggested by a viral load higher in the cerebrospinal fluid than in the peripheral blood. The association of a central nervous system infection with the A variant of human herpesvirus 6 is interesting because of the difficulty in establishing a pathological role for this virus strain. Epstein-Barr virus DNA was detected in the patient's cerebrospinal fluid in association with human herpesvirus 6 DNA. The presence of the Epstein-Barr virus genomic sequences in the cerebro-spinal fluid was considered to be unimportant clinically., (Copyright 2001 Wiley-Liss, Inc.)

Twenty five cases of meningitis occurred in urban areas surrounding a city (Modena) in Northern Italy, in the period May-July 1999. When the patients were admitted to the Infectious Diseases Division of the University of Modena and Reggio Emilia Hospital and studied by virological and serological methods, the meningitis proved to have an enteroviral origin and enterovirus ECHO 4 type was responsible for all cases of illness. An epidemiological characteristic of the enteroviral meninigitis outbreak was the adult age in 23 out of the 25 patients (mean age 24.50 +/- 7.84 years). The monthly distribution of the aseptic meningitis cases was the following: five cases occurred in May, 13 in June and seven in July. The origin of the spread of the virus infection and the reason for its sudden end remained unknown. The unusual drop in temperature which occurred in the geographic area involved in the aseptic meningitis outbreak at the beginning of August could have interfered with the slowdown in virus circulation.