Malaria transmission through the mosquito requires the function of the OMD protein

Ookinetes, one of the motile and invasive forms of the malaria parasite, rely on gliding motility in order to establish an infection in the mosquito host. Here we characterize the protein PBANKA_0407300 which is conserved in the Plasmodium genus but lacks significant similarity to proteins of other eukaryotes. It is expressed in gametocytes and throughout the invasive mosquito stages of P. berghei, but is absent from asexual blood stages. Mutants lacking the protein developed morphologically normal ookinetes that were devoid of productive motility although some stretching movement could be detected. We therefore named the protein Ookinete Motility Deficient (OMD). Several key factors known to be involved in motility however were normally expressed and localized in the mutant. Importantly, the mutant failed to establish an infection in the mosquito which resulted in a total malaria transmission blockade

Egress-related osmiophilic bodies

© 2014 John Wiley & Sons Ltd. Summary: Gametogenesis is the earliest event after uptake of malaria parasites by the mosquito vector, with a decisive impact on colonization of the mosquito midgut. This process is triggered by a drop in temperature and contact with mosquito molecules. In a few minutes, male and female gametocytes escape from the host erythrocyte by rupturing the parasitophorous vacuole and the erythrocyte membranes. Electron-dense, oval-shaped organelles, the osmiophilic bodies (OB), have been implicated in the egress of female gametocytes. By comparative electron microscopy and electron tomography analyses combined with immunolocalization experiments, we here define the morphological features distinctive of male secretory organelles, hereafter named MOB (male osmiophilic bodies). These organelles appear as club-shaped, electron-dense vesicles, smaller than female OB. We found that a drop in temperature triggers MOB clustering, independently of exposure to other stimuli. MDV1/PEG3, a protein associated with OB in Plasmodium berghei females, localizes to both non-clustered and clustered MOB, suggesting that clustering precedes vesicle discharge. A P.berghei mutant lacking the OB-resident female-specific protein Pbg377 displays a dramatic reduction in size of the OB, accompanied by a delay in female gamete egress efficiency, while female gamete fertility is not affected. Immunolocalization experiments indicated that MDV1/PEG3 is still recruited to OB-remnant structures

Vaccination coverage in healthcare workers: a multicenter cross-sectional study in Italy

IntroductionIn recent years, a phenomenon known as "vaccine hesitancy" has spread throughout the world, even among health workers, determining a reduction in vaccination coverage (VC). A study aimed at evaluating VC among healthcare workers (HCWs) in 10 Italian cities (L'Aquila, Genoa, Milan, Palermo, Sassari, Catanzaro, Ferrara, Catania, Naples, Messina) was performed.Materials and methodsAnnex 3 of the Presidential Decree n. 445 of 28 December 2000 was used to collect information on the vaccination status of HCWs. The mean and standard deviation (SD) were calculated with regard to the quantitative variable (age), while absolute and relative frequencies were obtained for categorical data (sex, professional profile, working sector, vaccination status). The connection between VC and the categorical variables was evaluated by chi-square method (statistical significance at p<0.05). The statistical analyses were performed by SPSS and Stata software.ResultsA total of 3,454 HCWs participated in the project: 1,236 males and 2,218 females. The sample comprised: physicians (26.9%), trainee physicians (16.1%), nurses (17.2%) and other professional categories (9.8%). Low VC was generally recorded. Higher VC was found with regard to polio, hepatitis B, tetanus and diphtheria, while coverage was very low for measles, mumps, rubella, pertussis, chickenpox and influenza (20-30%). ConclusionsThis study revealed low VC rates among HCWs for all the vaccinations. Measures to increase VC are therefore necessary in order to prevent HCWs from becoming a source of transmission of infections with high morbidity and/or mortality both within hospitals and outside

Prescription appropriateness of anti-diabetes drugs in elderly patients hospitalized in a clinical setting: evidence from the REPOSI Register

Diabetes is an increasing global health burden with the highest prevalence (24.0%) observed in elderly people. Older diabetic adults have a greater risk of hospitalization and several geriatric syndromes than older nondiabetic adults. For these conditions, special care is required in prescribing therapies including anti- diabetes drugs. Aim of this study was to evaluate the appropriateness and the adherence to safety recommendations in the prescriptions of glucose-lowering drugs in hospitalized elderly patients with diabetes. Data for this cross-sectional study were obtained from the REgistro POliterapie-Società Italiana Medicina Interna (REPOSI) that collected clinical information on patients aged ≥ 65 years acutely admitted to Italian internal medicine and geriatric non-intensive care units (ICU) from 2010 up to 2019. Prescription appropriateness was assessed according to the 2019 AGS Beers Criteria and anti-diabetes drug data sheets.Among 5349 patients, 1624 (30.3%) had diagnosis of type 2 diabetes. At admission, 37.7% of diabetic patients received treatment with metformin, 37.3% insulin therapy, 16.4% sulfonylureas, and 11.4% glinides. Surprisingly, only 3.1% of diabetic patients were treated with new classes of anti- diabetes drugs. According to prescription criteria, at admission 15.4% of patients treated with metformin and 2.6% with sulfonylureas received inappropriately these treatments. At discharge, the inappropriateness of metformin therapy decreased (10.2%, P < 0.0001). According to Beers criteria, the inappropriate prescriptions of sulfonylureas raised to 29% both at admission and at discharge. This study shows a poor adherence to current guidelines on diabetes management in hospitalized elderly people with a high prevalence of inappropriate use of sulfonylureas according to the Beers criteria

Protein trafficking and host cell remodling in malaria parasite infection

Il Plasmodio della malaria si riproduce nell’eritrocita, una cellula che ha perso capacità di sintesi poiché è altamente specializzata nel trasporto di ossigeno. La sopravvivenza del parassita è strettamente collegata alla riorganizzazione del citoplasma e della superficie del globulo rosso tramite la generazione di strutture membranose composte sia da molecole esportate dal parassita, che da altre importate dalla cellula ospite. Plasmodio garantisce così i nutrienti necessari al suo sviluppo e la possibilità di esportare fattori di virulenza alla superficie della cellula ospite. Tre membri della famiglia genica sep di P. berghei denominate SEP (Small Exported Proteins- 13-16 KDa), che presentano similarità con le proteine ETRAMP di P. falciparum, mostrano caratteristiche peculiari: condividono quasi totalmente la sequenza codificante, contenente un peptide segnale e una regione transmembrana, mentre differiscono nella porzione C-terminale. Anche la regione del promotore è pressoché identica, mentre variano gli specifici 3’UTR. Con la generazione di anticorpi specifici della regione al C-terminale, è stato possibile definire che si tratta di proteine integrali di membrana, la cui localizzazione e stadio specificità sono sorprendentemente diverse: in particolare la SEP2 e la SEP3 vengono esportate nella cellula ospite, mentre la SEP1 risiede alla membrana del vacuolo parassitoforo, struttura di interfaccia tra il parassita ed l’eritrocita. Inoltre è stato osservato che la SEP1 e 3 sono espresse in livelli confrontabili negli stadi intraeritrocitari, mentre la SEP2 è abbondantemente espressa nei gametociti, dato significativo in quanto questi sono le uniche forme ingerite dalla zanzara anofelina durante il pasto di sangue che daranno origine a parassiti in grado di svilupparsi nell’insetto vettore. Anche nell’insetto le 3 SEP hanno un profilo di espressione differente: SEP1 e 3 sono presenti negli ookineti, mentre la SEP2 è abbondantemente espressa in ookineti, oocisti e sporozoiti. L’identificazione dei motivi proteici necessari alla localizzazione delle proteine SEP2 e SEP3 nei vari distretti dell’eritrocita infetto si è basata sulla generazione di linee transgeniche di P. berghei in grado di esprimere porzioni diverse delle proteine SEP fuse alla proteina reporter GFP: la contemporanea presenza del peptide segnale della regione transmembrana è necessaria per traslocare le proteine di fusione SEP/GFP nell’eritrocita. La seconda parte del lavoro è stata svolta presso l’Università di Montpellier 2, e si propone di caratterizzare la localizzazione di due proteine del complesso giunzionale del citoscheletro dell’eritrocita umano, la dematina e l’adducina, in quanto recenti esperimenti svolti con il parassita murino hanno suggerito la possibilità di un meccanismo di internalizzazione di entrambe. Avvalendosi dell’impiego di anticorpi specifici e dell’utilizzo del microscopio confocale e apotome, è stato osservato che entrambe sono associate a comparti del parassita. Il processo di internalizzazione di queste due proteine è stato inoltre dimostrato attraverso esperimenti di frazionamento subcellulare e successiva digestione con proteinasi K: La dematina è interamente protetta e quindi completamente internalizzata dal parassita mentre l’adducina è in parte digerita dalla proteinasi K e quindi parzialmente esposta nel citoplasma dell’eritrocita.Plasmodium endurance depends on the ability of the parasite to reorganize the cytosol of the erythrocyte, a terminally differentiated cell, and remodels its skeleton membrane immediately after invasion. In this way the parasite can organize the import/export of the molecules necessary to its survival. The comprehension of cellular trafficking mechanisms which occur during Plasmodium infection is a very important step and fundamental contribute to understand the biology of the malaria parasite. We identified in the rodent malaria parasite Plasmodium berghei the gene family sep, corresponding to etramp in P. falciparum, encoding small exported proteins conserved in the genus Plasmodium. SEP proteins (13–16 kDa) contain a predicted signal peptide at the NH2-terminus, an internal hydrophobic region while they differ in their C-terminal region; the genes share the upstream regulative region while they differ in the 3’UTR. Despite this, we showed that SEPs have a different timing of expression and a different localization: in the erythrocytic cycle PbSEP1 and PbSEP3 start to be expressed at trophozoite and the same amount of protein is detected also in schizonts and gametocytes, while PbSEP2 is highly detected in mature trophozoites and even more in gametocytes. In mosquitoes stages PbSEP1 and PbSEP3 are expressed only in ookinetes, while PbSEP2 is very abundant in ookinetes, oocysts and in sporozoites of the salivary glands. SEPs also have a different localization in the iRBC: PbSEP1 is targeted to the membrane of the parasitophorous vacuole, while PbSEP2 and 3 are exported beyond the parasite membrane and translocated to the host cell compartment in association with vesicle-like structures. In this study we identified the specific signals necessary for the correct timing of expression and to direct SEP proteins to the vacuolar membrane and to the host cell compartments. The second part of the work was carried out in Montpellier II University and aims to identify the localization of two RBC membrane skeleton components, dematin and adducin, during Plasmodium falciparum infection. Our purpose is to recognize a possible mechanism of internalization of host cytoskeleton components to the parasite compartments. In fact, IFA experiments carried on iRBCs showed that dematin and adducin start to be internalized at trophozoite stage and localize at the periphery of the parasite, most probably at the parasitophoruos vacuole (PV) membrane/lumen. Dematin and adducin internalization during Plasmodium infection is also demonstrated by subcellular fractionation and proteinase K (PK) assay: while dematin is fully internalized, adducin is partially protected and suggesting a localization of the protein at the periphery of the parasite where it can be exposed to PK degradation

My new office

Negli abituali rapporti con le cose tendiamo a dare per scontata la loro familiare presenza che il nostro sguardo tende a rivestire di senso nella misura in cui risultano essere utili. Quando non servono più le dismettiamo. Le gettiamo via o le regaliamo, nella più nobile ipotesi che esse possano riacquistare senso in altri luoghi o in altri spazi. Quello che non consideriamo quasi mai e che, invece, balza chiarissimo ai nostri occhi in rare occasioni è che le cose, anche quelle più banali, hanno un’anima. Il cucchiaio di legno con il quale mia nonna rimestava il sugo, la poltrona sulla quale il babbo, a fine giornata mi prendeva sulle sue ginocchia e mi raccontava una storia, il tavolo di legno sul quale studiavo o l’abito che indossavo agli esami dell’Università. E poi, l’anello di fidanzamento, la penna “importante” ricevuta dalla migliore amica il giorno della laurea. Tutte cose “banali” che acquisiscono un valore, anche molto alto, tale che non vogliamo separarcene, tanto da preservare la loro esistenza tramandandole in modo quasi rituale “di padre in figlio”. Fin qui, appare chiaro che questa stratificazione di senso è un processo legato al modo in cui noi, meglio, la nostra mente vede questi oggetti. È il mio sguardo, il portato emotivo del mio sguardo ad attribuire senso e valore alle cose. Sono oggetti che rappresentano delle ancore, la manifestazione materiale di certezze che sono davanti ai miei occhi. Questo processo fa sì che, con il passare del tempo, quelle cose vivano di vita propria. Ecco, dunque, che #mynewoffice irrompe, con raffinata ironia, scardinando questa visione del rapporto fra noi e le cose ed estendendo a tutte le cose la capacità di vivere di vita propria tanto quanto ne rideterminiamo il significato. Ogni scatto presenta un mondo che Pasquale Leccese significa attraverso l’uso studiato dell’outfit. Ciò che indossa offre una chiave di lettura di quello che popola il mondo attorno a lui. È il modo del suo stare che suggerisce al fruitore come immaginare la storia che quell’immagine racconta. Inserisce elementi come riviste o libri che denotano il pensiero o il messaggio che l’hashtag, in un secondo momento, rimarca, soprattutto quando le immagini sono prive della sua presenza. Le cose dialogano con chi le guarda ed il lessico è solo quello dell’occhio. Il logos, la lettera, viene dopo per dichiarare che il modo in cui noi facciamo è lo specchio di quello che si è e che, qualunque sia la condizione, siamo noi con il nostro portato emotivo a qualificare il luogo che abitiamo, attribuendogli quello che i latini definivano il genius loci

Habituation of Somatosensory Evoked Potentials in Patients with Alzheimer’s Disease and Those with Vascular Dementia

Background and Objectives: The most prevalent dementia are Alzheimer’s disease and vascular dementia. There is evidence that cortical synaptic function may differ in these two conditions. Habituation of cortical responses to repeated stimuli is a well-preserved phenomenon in a normal brain cortex, related to an underlying mechanism of synaptic efficacy regulation. Lack of habituation represents a marker of synaptic dysfunction. The purpose of this study was to assess the habituation of somatosensory evoked potentials (SEPs) in 29 patients affected by mild-to-moderate Alzheimer’s disease (AD-type) or vascular (VD-type) dementia. Materials and Methods: All patients underwent a clinical history interview, neuropsychological evaluation, and neuroimaging examination. SEPs were elicited by electrical stimulation of the right median nerve at the wrist. Six-hundred stimuli were delivered, and cortical responses divided in three blocks of 200. Habituation was calculated by measuring changes of N20 amplitude from block 1 to block 3. SEP variables recorded in patients were compared with those recorded in 15 age- and gender-matched healthy volunteers. Results: SEP recordings showed similar N20 amplitudes in AD-type and VD-type patients in block 1, that were higher than those recorded in controls. N20 amplitude decreased from block 1 to block 3 (habituation) in normal subjects and in VD-type patients, whereas in AD-type patients it remained unchanged (lack of habituation). Conclusions: The findings suggest that neurophysiologic mechanisms of synaptic efficacy that underneath habituation are impaired in patients with AD-type dementia but not in patients with VD-type dementia. SEPs habituation may contribute to early distinction of Alzheimer’s disease vs. vascular dementia

Effectiveness of Botulinum Toxin on Pain in Stroke Patients Suffering from Upper Limb Spastic Dystonia

This observational study aimed at investigating pain in stroke patients with upper limb spastic dystonia. Forty-one consecutive patients were enrolled. A 0–10 numeric rating scale was used to evaluate pain at rest and during muscle tone assessment. Patients were asked to indicate the most painful joint at passive mobilization (shoulder, elbow, wrist-fingers). The DN4 questionnaire was administered to disclose neuropathic pain. All patients were assessed just before and 1 month after incobotulinumtoxin-A treatment. Pain was present in 22 patients, worsened or triggered by passive muscle stretching. DN4 scored < 4 in 20 patients. The most painful joints were wrist–fingers in 12 patients, elbow in 5 patients and shoulder in the remaining 5 patients. Both elbow and wrist–fingers pain correlated with muscle tone. BoNT-A treatment reduced pain in all the joints, including the shoulder. We discussed that nociceptive pain is present in a vast proportion of patients with upper limb spastic dystonia. BoNT-A treatment reduced both spastic dystonia and pain in all the joints but the shoulder, where the effect on pain could be mediated by the reduction of pathological postures involving the other joints