Evaluation of Mastadenovirus and Rotavirus Presence in Phyllostomid, Vespertilionid, and Molossid Bats Captured in Rio Grande do Sul, Southern Brazil

Bat-borne viruses may affect public health and the global economy. These mammals have a wide geographical distribution and unique biological, physiological, and immunogenic characteristics, allowing the dissemination of many known and unknown viruses. Enteric viruses, such as adeno (AdV) and rotaviruses, are recognized as the main causative agents of disease and outbreaks. In the present study, the presence of viruses from Adenoviridae and Reoviridae families was evaluated in molossid, phyllostomid, and vespertilionid bats captured in Rio Grande do Sul, Southern Brazil, between September 2021 and July 2022. Sixty bat rectal swabs were analyzed by PCR. Eight (13.3%) samples were positive for adenovirus and classified as human mastadenovirus C (HAdV-C) (three samples) and HAdV-E (five samples) by sequencing followed by phylogenetic analysis. All samples were negative in rotavirus specific RT-PCR. This is the first study to describe the presence of HAdV in samples of Glossophaga soricina, Eptesicus brasiliensis, and Histiotus velatus. Furthermore, the presence of HAdV-E in bats was reported, which is unusual and may suggest that other HAdV genotypes, in addition to HAdV-C, may also be harbored by wild animals. The data generated in the present study reinforces the importance of eco-surveillance of viral agents related to diseases in humans and wild animals. In addition, it is essential to identify possible new hosts or reservoirs that increase the risk of spillover and dissemination of infectious pathogens, helping to prevent and control zoonotic diseases.

See me, feel me. Using physiology to validate behavioural observations of emotions of people with severe or profound intellectual disability

BACKGROUND

Behavioural observations are the most frequently used source of information about emotions of people with severe or profound intellectual disabilities but have not yet been validated against other measures of emotion. In this study we wanted to validate the behavioural observations of emotions using respiration (rib cage contribution, total breath duration, inspiratory time, expiratory time, tidal volume, mean inspiratory flow, minute ventilation) and heart rate variability.

METHOD

Twenty-seven participants were presented with four negative and four positive stimuli. During the presentation the participants' respiration and heart rate variability was measured. Each behaviour of the participant was coded as emotive or not.

RESULTS

We found the hypothesised higher percentage rib cage contribution, marginal lower mean inspiratory flow and lower heart rate variability when the expressed emotions became more positive.

CONCLUSIONS

These results validate the use of behavioural observations to make inferences about emotions.

Investigating the relationship between observed mood and emotions in people with severe and profound intellectual disabilities

BACKGROUND

The measurement of subjective well-being in people with severe and profound intellectual disabilities (ID) is a difficult challenge. As they cannot self-report about their life satisfaction, because of severe communicative and cognitive limitations, behavioural observations of their emotions and moods are important in the measurement of their subjective well-being. It is, however, not known if observations of mood and emotion can be differentiated in people with severe and profound ID and if mood and emotions can give unique information about their affect. Therefore, the aim of this study is to examine the relationship between mood and emotions in people with severe and profound ID, using behavioural observations. As recommended in the literature, we investigated the frequency and intensity of the emotion separately.

METHOD

In a period of 3 weeks 27 participants with severe and profound ID were presented with four staff-selected negative and four staff-selected positive stimuli. During the presentation participants were videotaped using the observational method of Petry & Maes where each behaviour is coded on a 5-point scale, ranging from indicating a very negative emotion to indicating a very positive emotion. As a measure of mood, the staff completed the MIPQ in the beginning of the 3 weeks.

RESULTS

We found a positive relationship between mood and respectively the total emotion score and the frequency of the emotion when the stimuli were positive but not when the stimuli were negative. There was no relationship between mood and the intensity of the emotion.

CONCLUSIONS

Our results indicate that mood and emotions can be distinguished from each other using behavioural observations. Both can give specific information about the affective life of people with severe or profound ID. Moreover, if further research could replicate the results of this study, an implication is that the direct support workers should be aware of a decline in the frequency of their clients reactions to positive stimuli as this could indicate a decline in their mood.

How do children with a chronic or long-term illness perceive their school re-entry after a period of homebound instruction?

BACKGROUND

A considerable number of children are confronted with a chronic or long-term illness in their lives. For these children, absenteeism is problematic, because education plays a major role in stimulating their cognitive development and in promoting a sense of normalcy and psychosocial well-being. In the literature, a great deal of attention has been paid to school reintegration programmes, which try to counter the barriers that these children may face when they return to school. Another way of surmounting these barriers is through the use of homebound instruction, in which the educational process for the child is continued during the period of absence. Despite the growing awareness of the necessity of education for these children, there is still little empirical research available addressing programmes that facilitate school re-entry.

METHODS

The major goal of this study is to investigate how parents and their children with a chronic or long-term illness perceive school re-entry after a period of homebound instruction, by using a descriptive-explorative, multi-informant research design. Participants were 60 children and their parents who filled in a self-constructed questionnaire.

RESULTS

Both parents and children perceived the period of homebound instruction, as well as their school re-entry, predominantly positively. Most of the children stated that they had been able to keep up with their subjects, and that they had good contact with their peers when they returned to school. According to parents, homebound instruction made a positive contribution to the school re-entry of their child.

CONCLUSIONS

The current study is one of the first to explore the school re-entry of children with a chronic or long-term illness. According to both parents and children, the school re-entry process passed off positively. However, more research is needed with regard to the quality of education and the programmes aimed at facilitating school re-entry.

Operationalizing quality of life for people with profound multiple disabilities: a Delphi study

BACKGROUND

In a recent study, we constructed an item pool that contains items on the quality of life (QOL) and related aspects of support of people with profound multiple disabilities (PMD). In the present study, a panel of experts assessed the content and the structure of this item pool in order to enhance its validity and usefulness.

METHOD

A two-round Delphi study was set up. The panel consisted of 45 experts, of whom 12 were theory-experts, 12 practice-experts and 12 experience-experts from Belgium (n = 12), Germany (n = 12), the Netherlands (n = 11) and the UK/Ireland (n = 10). Both quantitative and qualitative methods of analysis were applied to the data.

RESULTS

The majority of the items were considered relevant for the QOL of people with PMD. In the first round, 91% of the items reached the 80% criterion of consensus. In the second round, 78.7% of the items reached the 85% criterion of consensus. There were no significant differences in opinion neither between types of experts nor between countries. Several items were reported as missing in the item pool and were added.

CONCLUSIONS

The results provide some evidence that the item pool is a valid operationalization of QOL of people with PMD and can be used in an instrument to measure the QOL of this target group.

Anti-myelin-associated glycoprotein antibodies and endoneurial cryoglobulin deposits responsible for a severe neuropathy

A 73-year-old man was investigated for a peripheral neuropathy which occurred in the course of a Waldenstrom's macroglobulinemia. Serum immuno-fixation electrophoresis demonstrated two IgM monoclonal gammopathies of the kappa and lambda chain isotypes, and one had the physical characteristics of cryoglobulin. Immunoblot studies on the patient's serum revealed antibodies which reacted with peripheral nervous system proteins of different molecular weights including the myelin-associated glycoprotein (MAG). An immunofluorescence study of a superficial peroneal nerve biopsy revealed not only a binding of IgM and kappa light chain on several myelin sheaths but also the presence of IgM and kappa light chain deposits in the endoneurium. On electron microscopic examination, numerous fibres presented a widely spaced myelin and the endoneurial deposits had the ultrastructure of cryoglobulin. This is the first case presenting features of widely spaced myelin related to serum anti-MAG activity associated with monoclonal cryoglobulin deposits in the endoneurium.

Histopathological variants of central neurocytoma: Report of 10 cases

Central neurocytoma is a rare neuronal tumor affecting young adults and usually located in the lateral ventricles. Post-operative prognosis is generally good. Histologically, central neurocytoma is composed of isomorphous small round or ovoid cells alternating with irregularly shaped patches of fibrillary matrix similar to the neuropile. In a series of 10 cases, two central neurocytomas were histologically "atypical" at first examination. One was intra-ventricular, and the second had an intra-parenchymatous juxta-ventricular location. Both were highly cellular with mitotic activity, and tumor necrosis was seen in one. Neuronal differentiation was assessed by synaptophysin immunoreactivity in all 10 cases and by ultrastructural examination in four, including the two "atypical" forms. Neuronal differentiation was less marked in these "atypical" forms, one also presenting focal GFAP immunoreactivity. The proliferative potential was determined by MIB-1 labeling index and compared with clinical outcome. The eight classical central neurocytomas had a MIB-1 labeling index < 2.3%, whereas the two "atypical" forms had a MIB-1 labeling index > 5.2% and both recurred. We think that there is a spectrum of small-cell neuronal tumors. The two extremes could be the central neurocytoma and the primary cerebral neuroblastoma, while the intermediate forms might be qualified as "atypical neurocytoma". In our series, the histological and immunohistochemical criteria of biological aggressiveness appeared to be high mitotic activity, tumor necrosis, loss of neuronal differentiation and high MIB-1 labelling index.

Inexcitability of nerves in a fulminant case of Guillain-Barré syndrome

A 45-year-old woman presented with a recent sensorimotor deficiency in all 4 limbs, and the next day she was totally paralyzed. A slight motor improvement began on day 27. The cerebrospinal fluid had normal cellularity, but the protein varied from 90 mg/dL on the first day to 800 mg/dL on day 15, and then 290 mg/dL on day 33. Electrophysiologic studies performed on days 15 and 23 revealed a universal peripheral nerve inexcitability. A superficial peroneal nerve biopsy was performed on day 23. Nine fascicles were examined on semi-thin sections and myelinated fiber damage varied greatly from one fascicle to another. At ultrastructural examination, certain axons were severely damaged, but the others were quite well preserved and were naked or wrapped in a myelin sheath presenting a multivesicular degeneration. A few fibers had a better-preserved myelin sheath that was sometimes dissociated by elongated processes from an invading histiocyte. Six cases of fulminant Guillain-Barré syndrome with inexcitability of nerves and ultrastructural examination of nerve fragments have been reported. Electrophysiologic study is often ambiguous and cannot determine the precise origin of such an axonal degeneration. Therefore, ultrastructural analysis of a nerve biopsy is mandatory in this setting.

An extrachromosomal switch recombination substrate reveals kinetics and substrate requirements of switch recombination in primary murine B cells

Ig class switch recombination occurs in B lymphocytes upon activation, and is targeted to distinct switch (S) regions by cytokine-mediated induction of switch transcripts spanning the entire S region and the adjacent constant region gene segments. Using a novel type of switch recombination substrate, constructed according to the intron-exon structure of the IgH locus, but with heterologous elements, we here have tested the structural requirements for targeting and the kinetics of switch recombination in activated primary murine B cells. When transfected at various times after activation, up to 10% of the transfected B cells perform recombination of the substrate within 12 h. Switch recombination in primary B cells is restricted to the first 72 h after onset of activation, then rapidly decreases to background levels, as obtained in plasmacytoma cells or with substrates carrying no S region sequences. In terms of structural requirements, switch recombination is targeted to any transcription unit that contains an intronic S region and depends on processing of the primary transcript by splicing.

Processing of switch transcripts is required for targeting of antibody class switch recombination

Antibody class switching is mediated by somatic recombination between switch regions of the immunoglobulin heavy chain gene locus. Targeting of recombination to particular switch regions is strictly regulated by cytokines through the induction of switch transcripts starting 5' of the repetitive switch regions. However, switch transcription as such is not sufficient to target switch recombination. This has been shown in mutant mice, in which the I-exon and its promoter upstream of the switch region were replaced with heterologous promoters. Here we show that, in the murine germline targeted replacement of the endogenous gamma1 promoter, I-exon, and I-exon splice donor site by heterologous promoter and splice donor sites directs switch recombination in activated B lymphocytes constitutively to the gamma1 switch region. In contrast, switch recombination to IgG1 is inhibited in mutant mice, in which the replacement does not include the heterologous splice donor site. Our data unequivocally demonstrate that targeting of switch recombination to IgG1 in vivo requires processing of the Igamma1 switch transcripts. Either the processing machinery or the processed transcripts are involved in class switch recombination.

Increasing melanoma incidence: putatively explainable by retrotransposons. Experimental contributions of the xiphophorine Gordon-Kosswig melanoma system

The worldwide accelerating increase of neoplasia in humans is difficult to explain. We use the Xiphophorus tumor model to approach this problem by melanoma provocation with X-rays. Melanoma develops following inappropriate expression of x-erb B-conducted developmental genes and their controllers. These oncodeterminants are inherited according to Mendelian rules. We detected a new type of oncodeterminants that, following a single treatment of embryos with X-rays, generates a self-generating non-Mendelian melanoma transmission and accelerating increase of its incidence in succeeding generations (e.g., 0-->18-->33-->52%). To localize these oncodeterminants, we crossed nonirradiated fish having half of their chromosomes irradiated with nonirradiated fish having none of, half of, or all of their chromosomes irradiated. Because tumor rate and expression in the following generations correspond to the rates of treated chromosomes, we conclude that the new oncodeterminants are distributed over the chromosomes of the fish, where they may increase in the changing generations. By means of xiphophorine-specific retroviral DNA, we isolated two retrotransposons that behave hereditarily like the new transgenerational oncodeterminants. Sequence analysis revealed three ORFs flanked by LTRs containing motives of regulatory sequences typical for known retroviral and retrotransposal LTRs. Pol- and env-resembling sequences are lacking. Southern and in situ hybridization showed their multiple and repetitive nature distributed throughout the chromosomes and indications for their capability to increase in number without further treatment. Their transcripts are expressed in concert with those of most of the other known xiphophorine tumor determinants. Their expression is extremely high in cell cultures from tumorous embryos derived from ancestors treated as embryos with X-rays.

Isolation and characterization of a retrovirus from the fish genus Xiphophorus

A cell line (BsT) established from neoplastic embryonal tissues of the platyfish (Xiphophorus maculatus) released spontaneously retrovirus-like particles. The particles have a buoyant density of 1.16 g/ml, a mean diameter of 100 nm and the morphology of immature retroviruses. The particle-associated proteins p70, p65, and p28 react with an antiserum directed against the major internal feline leukemia virus structural protein p27. The particles are associated with a reverse transcriptase. The purified enzyme has a molecular weight of about 70 kDa and prefers the template primers poly(rA):oligo(dT), poly(dC):oligo(dG), and poly(rC):oligo(dG) in the presence of Mn2+. The enzyme activity is inhibited by antibodies directed against the reverse transcriptase of feline leukemia virus and simian sarcoma virus. The particles contain a ribonucleic acid of about 70 S. In an endogenous reverse transcriptase reaction nucleic acids in the range of 0.2 to 0.4 kb were synthesized. In Northern blots with these nucleic acids as probe, three transcripts of about 8.5, 4.2, and 1.5 kb were detected in BsT cells. Southern blot analysis with the same probe demonstrates related sequences in the DNA of BsT cells and the platyfish and swordtail (Xiphophorus helleri). Hybridization experiments with the LTR-gag region of the feline leukemia virus show homologous sequences in the Xiphophorus genome.

Characterization of a novel biochemical abnormality in galactosemia: deficiency of glycolipids containing galactose or N-acetylgalactosamine and accumulation of precursors in brain and lymphocytes

Classic galactosemia, an inborn error of human galactose metabolism, is characterized by a deficiency of the enzyme galactose-1-phosphate uridyltransferase (GALT). The current model for the pathophysiology of this disease ascribes most of its symptoms to the toxicity of intracellular galactose-1-phosphate (Gal-1-P), one of the substrates of GALT which accumulates in the untreated disease state. Recently, a reduction in the intracellular concentration of UDP-Gal (uridine diphosphogalactose), one of the products of GALT, has been described in treated galactosemic patients. We investigated whether galactosemic patients might also have reduced amounts of those macromolecules that depend on UDP-Gal for their biosynthesis. We report a reduction in glycolipids that contain either galactose or its derivative N-acetylgalactosamine and an accumulation of the precursors to these compounds in the brain of a neonate with galactosemia. We also found an imbalance in glycolipids in galactosemic lymphoblasts. This novel biochemical abnormality observed in galactosemic patients is not addressed by dietary galactose-restriction therapy and could explain some of the chronic neurologic and other complications of galactosemia.

Chagas disease: A model for the study of autoimmune diseases

There are few natural animal model systems to study autoimmune disease caused by infectious agents; however, Trypanosoma cruzi infection of the mouse offers an excellent model for the induction of autoimmunity and its consequences. In this article Klaus Petty and Harvey Eisen explain that it is probably during the acute phase of the infection that the stage is set for the long-term pathology.

Sulfated lipids represent common antigens on the surface of Trypanosoma cruzi and mammalian tissues

Cross-reacting lipid antigens were isolated from Trypanosoma cruzi and the mammalian brain with the monoclonal antibody VESP 6.2. Chemical reactions indicated that the sulfate group of the lipids is an important part of the epitope recognized by the monoclonal antibody. Lipid extracts of mouse brain contained all the antigenic species present in the parasite. One of the antigens was demonstrated by three different methods: (i) high performance thin layer chromatography immunostaining, (ii) solid phase radioimmunoassay, (iii) lysis of artificial liposomes. The T. cruzi sulfated lipid antigens were shown to be of parasite origin rather than scavenged from the culture medium. They could be radiolabelled with [35S]sulfate. Furthermore, lipid extracts from two T. cruzi strains grown in different media contained the same antigens while the media contained either no antigens or different species.

Complex lipids as common antigens to Trypanosoma cruzi, T. dionisii, T. vespertilionis and nervous tissue (astrocytes, neurons)

In a dot immunobinding test glycolipid and phospholipid antigens were recognized by anti-T. dionisii (DION) and anti-T. vespertilionis (VESP) monoclonal antibodies (mabs). Five of them crossreact with T. cruzi and cells of the central nervous system (CNS) (astrocytes, neurons). Indirect immunofluorescence (IIF) of neuraminidase treated T. cruzi cells indicated that two antigens were organized in a cryptic form.

Epitopes common to trypanosomes (T. cruzi, T. dionisii and T. vespertilionis (Schizotrypanum)): astrocytes and neurons

An autoimmune mechanism is commonly invoked to explain the occurrence of neuronal destruction in the chronic phase of Chagas' disease. Monoclonal antibodies raised against T. dionisii (DION) and T. vespertilionis (VESP), and cross-reactive with T. cruzi recognize antigens in cultured cerebellar cells from embryonic and postnatal mice, as revealed by indirect immunofluorescence. Astrocytes (labelled with rabbit anti-GFAP antibody) showed positive reactions with DION 12.7, VESP 8.2 and VESP 9.3 while neurons (labelled with either tetanus toxin or anti-neuron-specific enolase antibody) reacted with the monoclonal antibody DION 10.1b. VESP 6.2 reacted with living cells of a subpopulation of neuronal or unidentifiable cell type. These cross-reactions may explain why not only neurons but also astrocytes may be involved in the autoimmune damage.

Purification of metacyclic trypomastigotes of Trypanosoma cruzi and Trypanosoma dionisii from culture using an epimastigote-specific monoclonal antibody

Monoclonal antibodies which react with culture forms of Trypanosoma dionisii and Trypanosoma cruzi were tested for their agglutination capacity. In these studies developmental stage specificity for the epimastigote form could be observed. This specificity meant it was possible to develop a quick and simple method to isolate cultured metacyclic trypomastigotes of T. dionisii and T. cruzi group 2. After agglutination of the epimastigote form with the monoclonal antibody Dion 4.6 the purity of metacyclic trypomastigote developmental forms derived from culture was 96% to 99%.

Characterization of a 19,000 mol. wt. flagellum-specific protein of Trypanosoma cruzi, T. dionisii and T. vespertilionis by a monoclonal antibody

The flagellum-specific monoclonal antibody VESP 9.1 raised against Trypanosoma vespertilionis reacts with a single protein band of 19,000 mol. wt.. This antigen is present on the flagellum of T. cruzi, T. dionisii and T. vespertilionis as well on the epimastigote and the metacyclic trypomastigote developmental stage. A comparative study using indirect immunofluorescence with 15 different trypanosomatids confirmed the specific reactions.

Differentiation of Trypanosoma cruzi, T. cruzi marinkellei, T. dionisii and T. vespertilionis by monoclonal antibodies

Anti-T. dionisii and anti-T. vespertilionis monoclonal antibodies secreted by 17 hybridoma clones were tested against various strains of T. dionisii, T. vespertilionis, T. cruzi and T. cruzi marinkellei. Strain and species specific antigens were detected for the homologous immunizing strains. The common antigenic determinants of the tested trypanosome species include a component of the flagellum and different cell structures. Seventeen T. cruzi strains could be classified into two groups when tested with anti-T. dionisii monoclonal antibodies. The cross reactions between T. dionisii and T. cruzi demonstrate a strong correlation between T. dionisii and T. cruzi group 2. On the other hand T. cruzi group 1 and T. cruzi marinkellei show very similar antigenic character.

The removal of hypnotic drugs from human serum. A comparative investigation of the adsorptive properties of native and agarose-encapsulated resins and charcoal

The adsorptive capacities of some ion-exchange resins and activated charcoal towards the hypnotic drugs, phenobarbital, glutethimide, carbromal, and methaqualone, have been investigated. Furthermore, the properties of some of these resins and charcoal, encapsulated in an agarose matrix in the form of beads, have been compared with those of the adsorbent phases in their native states. In general, the adsorptive capacities of charcoal were at least as good as, and frequently better than those of the resins. Amberlite XAD-type resins had a higher affinity than Dowex-type resins for all the drugs tested, except for phenobarbital, which was not adsorbed to a satisfactory extent onto Amberlite XAD-4. The encapsulation of adsorbent phases into agarose beads of diameter 5-10 mm results in a reduction of the adsorbtion of the drugs. Nonetheless, the remaining adsorptive capacity is sufficient for application in an extracorporeal detoxification system. Moreover, the overwhelming advantage of good haemocompatibility is provided by the agarose-encapsulated adsorbents.