Occurrence of nitric oxide synthase in Megoura viciae Buckton (Homoptera, Aphididae): an histochemical and immunohistochemical localisation

Nitric oxide (NO) is known to be involved in many physiological reactions of insects. We analysed NOS localisation in aphids of the species Megoura viciae by means of histochemical reaction for the NADPH-diaphorase activity and immunohistochemical methods for uNOS, nNOS and iNOS. The obtained data provided a complex and peculiar pattern of NOS distribution in cells and tissue of M. viciae.The histochemical reaction for NADPH-diaphorase was an indicative, but not exact marker of NOS localisation in aphids. The use of anti uNOS antiserum (frequently applied in insects) was of limited value in our specimens, whereas more satisfactory results were obtained with anti nNOS and iNOS antisera of human origin. The results of Western blot analysis confirmed the immunohistochemical ones, showing an aphid protein that reacted strongly with the polyclonal antibody anti-iNOS and anti-nNOS while a similar protein band was weakly immunoreactive with the polyclonal antibody anti-uNOS. Our results suggest that NO, prevalently synthesised by calcium/calmodulin-dependent isoform, plays important physiological roles both in adult and embryological stages of aphids. The data of principal interest was NOS presence in bacteriocytes, cells that host symbiotic prokaryotes belonging to the species Buchnera aphidicola, and in nuclei of adipocytes and gut cells

Cytogenetic analysis of the holocentric chromosomes of the aphid Schizaphis graminum

Chromatin organization in the holocentric chromosomes of the aphid Schizaphis graminum has been investigated at a cytological level after C-banding, NOR, Giemsa, DAPI and CMA(3) staining. C-banding technique showed the presence of numerous C bands on the two X chromosomes both in telomeric and intercalary regions, whereas autosomes show a small number of heterochromatic bands. Contrary to the results with other aphid species, in S. graminum the C-banding pattern is peculiar to each chromosome pair, thus allowing the identification of homologues and the reliable reconstruction of a karyotype. These cytogenetic data could be useful for the identification of chromosomal rearrangement eventually occurred between different S. graminum biotypes. Moreover, silver staining and fluorescent in situ hybridization (FISH) with a 28S rDNA probe localized rDNA genes on one telomere of each X chromosome; these are the only brightly fluorescent C-positive regions revealed after CMA(3) staining, whereas all other heterochromatic bands are DAPI positive

Why Was the Perception of Human Rights Respect and Care Satisfaction So High in Users of Italian Mental Health Services during the COVID-19 Pandemic?

The aim of this study was to compare users’ and mental health workers’ (MHW) perception of respect of human rights and job/care satisfaction in mental health services in Italy during the COVID-19 pandemic. A sample of users and MHW of Sardinia, Italy, fulfilled the “WellBeing at work and respect for human rights questionnaire” (WWRR). The study included 240 MHW and 200 users. Users showed a higher level of satisfaction of care than MHW of work, and a higher perception of the satisfaction of users and human rights respected for health workers. Both user and MHW responses were about 85% of the maximum score, except for satisfaction with resources. Responses were higher for users, but users and MHW both showed high levels of satisfaction. In previous surveys, MHW of Sardinia showed higher scores in all items of WWRR, except for satisfaction with resources, compared with workers from other health sectors of the same region, and with MHW from other countries. The low score for satisfaction with resources (in users and staff) is consistent with a progressive impoverishment of resources for mental health care in Italy. The study, although confirming the validity of the Italian model, fully oriented towards community, sets off an alarm bell on the risks resulting from the decrease in resources

Stress granules, RNA-binding proteins and polyglutamine diseases: too much aggregation?

Stress granules (SGs) are membraneless cell compartments formed in response to different stress stimuli, wherein translation factors, mRNAs, RNA-binding proteins (RBPs) and other proteins coalesce together. SGs assembly is crucial for cell survival, since SGs are implicated in the regulation of translation, mRNA storage and stabilization and cell signalling, during stress. One defining feature of SGs is their dynamism, as they are quickly assembled upon stress and then rapidly dispersed after the stress source is no longer present. Recently, SGs dynamics, their components and their functions have begun to be studied in the context of human diseases. Interestingly, the regulated protein self-assembly that mediates SG formation contrasts with the pathological protein aggregation that is a feature of several neurodegenerative diseases. In particular, aberrant protein coalescence is a key feature of polyglutamine (PolyQ) diseases, a group of nine disorders that are caused by an abnormal expansion of PolyQ tract-bearing proteins, which increases the propensity of those proteins to aggregate. Available data concerning the abnormal properties of the mutant PolyQ disease-causing proteins and their involvement in stress response dysregulation strongly suggests an important role for SGs in the pathogenesis of PolyQ disorders. This review aims at discussing the evidence supporting the existence of a link between SGs functionality and PolyQ disorders, by focusing on the biology of SGs and on the way it can be altered in a PolyQ disease context.ALG-01-0145-FEDER-29480, SFRH/BD/133192/2017, SFRH/BD/133192/2017, SFRH/BD/148533/2019info:eu-repo/semantics/publishedVersio

Attivit\ue0 NADPH-diaforasica e NO sintetasi in Megoura vciae Buckton (Homoptera, Aphididae)

Sono state condotte indagini istochimiche e immunoistochimiche per la localizzazione rispettivamente dell'attivit\ue0 NADPH-diaforasica e della uNOS (universal NOS), della nNOS e della iNOS. in organi e tessuti dell'afide Megoura viciae. Gli anticorpi anti-uNOS, comunemente utilizzati per gli insetti, non sono risultati particolarmente idonei in questa specie di afidi, mentre una immunoreattivit\ue0 molto pi\uf9 estesa \ue8 stata ottenuta con gli anticorpi anti-iNOS e anti-iNOS

Evidence of a female-produced sex pheromone in the European pear psylla, Cacopsylla pyri

Cacopsylla pyri (L.) (Hemiptera Psyllidae) is one of the most important pests of pear orchards in Europe that reduces the market value of pears. Summerform C. pyri males significantly preferred odours from living females or female cuticular extracts in the absence of visual stimuli in a Y-tube olfactometer. Conversely, males as well as females did not show any preference for odours from specimen of the same sex. Electroantennogram recordings showed that female cuticular extracts elicit dose-dependent responses in male antennae suggesting the presence of volatile compounds capable to stimulate the male peripheral olfactory system. Gas-chromatography coupled with mass spectrometry revealed marked quantitative differences between male and female cuticular extracts regarding 13-methylheptacosane, 11,13-dimethylheptacosane, 2-methylheptacosane, and 3-methylheptacosane. These compounds were found in larger amounts in female extracts which suggests their role in male attraction

Development of the wing buds in Megoura viciae: a morphological study

This study describes the initial phases of wing morphogenesis of Megoura viciae. We evaluated the development of wing buds in males (winged) and parthenogenetic females (presumed to become wingless) of M. viciae from birth to IV instar. Wing bud epithelium in males is initially simple, becoming bistratified and then progressing to stratify. Mitotic activity is more intense in the proximal region of bud, and its behaviour seems to be synchronous. In parthenogenetic females, from birth to I instar, the buds resemble those of males at the same stages, but subsequently the epithelium returns to the simple state, and from the III instar stage, it cannot be distinguished from the adjacent epithelium.This study moreover defines distinctive wing bud features that can be used to identify these buds during development in other aphid species