Trypanosoma cruzi Epimastigotes Are Able to Store and Mobilize High Amounts of Cholesterol in Reservosome Lipid Inclusions

Reservosomes are lysosome-related organelles found in Trypanosoma cruzi epimastigotes. They represent the last step in epimastigote endocytic route, accumulating a set of proteins and enzymes related to protein digestion and lipid metabolism. The reservosome matrix contains planar membranes, vesicles and lipid inclusions. Some of the latter may assume rectangular or sword-shaped crystalloid forms surrounded by a phospholipid monolayer, resembling the cholesterol crystals in foam cells.Using Nile Red fluorimetry and fluorescence microscopy, as well as electron microscopy, we have established a direct correlation between serum concentration in culture medium and the presence of crystalloid lipid inclusions. Starting from a reservosome purified fraction, we have developed a fractionation protocol to isolate lipid inclusions. Gas-chromatography mass-spectrometry (GC-MS) analysis revealed that lipid inclusions are composed mainly by cholesterol and cholesterol esters. Moreover, when the parasites with crystalloid lipid-loaded reservosomes were maintained in serum free medium for 48 hours the inclusions disappeared almost completely, including the sword shaped ones.Taken together, our results suggest that epimastigote forms of T. cruzi store high amounts of neutral lipids from extracellular medium, mostly cholesterol or cholesterol esters inside reservosomes. Interestingly, the parasites are able to disassemble the reservosome cholesterol crystalloid inclusions when submitted to serum starvation

Mesenteric lymph node transcriptome profiles in BALB/c mice sensitized to three common food allergens

<p>Abstract</p> <p>Background</p> <p>Food allergy is a serious health concern among infants and young children. Although immunological mechanism of food allergy is well documented, the molecular mechanism(s) involved in food allergen sensitization have not been well characterized. Therefore, the present study analyzed the mesenteric lymph node (MLN) transcriptome profiles of BALB/c mice in response to three common food allergens.</p> <p>Results</p> <p>Microarray analysis identified a total of 1361, 533 and 488 differentially expressed genes in response to β-lactoglobulin (BLG) from cow's milk, ovalbumin (OVA) from hen's egg white and peanut agglutinin (PNA) sensitizations, respectively (p < 0.05). A total of 150 genes were commonly expressed in all antigen sensitized groups. The expression of seven representative genes from microarray experiment was validated by real-time RT-PCR. All allergens induced significant ear swelling and serum IgG1 concentrations, whereas IgE concentrations were increased in BLG- and PNA-treated mice (p < 0.05). Treatment with OVA and PNA significantly induced plasma histamine concentrations (p < 0.05). The PCA demonstrated the presence of allergen-specific IgE in the serum of previously sensitized and challenged mice.</p> <p>Conclusions</p> <p>Immunological profiles indicate that the allergen dosages used are sufficient to sensitize the BALB/c mice and to conduct transcriptome profiling. Microarray studies identified several differentially expressed genes in the sensitization phase of the food allergy. These findings will help to better understand the underlying molecular mechanism(s) of food allergen sensitizations and may be useful in identifying the potential biomarkers of food allergy.</p

Genomic signatures of local adaptation reveal source-sink dynamics in a high gene flow fish species

Understanding source-sink dynamics is important for conservation management, particularly when climatic events alter species' distributions. Following a 2011 'marine heatwave' in Western Australia, we observed high recruitment of the endemic fisheries target species Choerodon rubescens, towards the cooler (southern) end of its distribution. Here, we use a genome wide set of 14 559 single-nucleotide polymorphisms (SNPs) to identify the likely source population for this recruitment event. Most loci (76%) showed low genetic divergence across the species' range, indicating high levels of gene flow and confirming previous findings using neutral microsatellite markers. However, a small proportion of loci showed strong patterns of differentiation and exhibited patterns of population structure consistent with local adaptation. Clustering analyses based on these outlier loci indicated that recruits at the southern end of C. rubescens' range originated 400 km to the north, at the centre of the species' range, where average temperatures are up to 3 °C warmer. Survival of these recruits may be low because they carry alleles adapted to an environment different to the one they now reside in, but their survival is key to establishing locally adapted populations at and beyond the range edge as water temperatures increase with climate change

Genetic fine mapping and genomic annotation defines causal mechanisms at type 2 diabetes susceptibility loci.

We performed fine mapping of 39 established type 2 diabetes (T2D) loci in 27,206 cases and 57,574 controls of European ancestry. We identified 49 distinct association signals at these loci, including five mapping in or near KCNQ1. 'Credible sets' of the variants most likely to drive each distinct signal mapped predominantly to noncoding sequence, implying that association with T2D is mediated through gene regulation. Credible set variants were enriched for overlap with FOXA2 chromatin immunoprecipitation binding sites in human islet and liver cells, including at MTNR1B, where fine mapping implicated rs10830963 as driving T2D association. We confirmed that the T2D risk allele for this SNP increases FOXA2-bound enhancer activity in islet- and liver-derived cells. We observed allele-specific differences in NEUROD1 binding in islet-derived cells, consistent with evidence that the T2D risk allele increases islet MTNR1B expression. Our study demonstrates how integration of genetic and genomic information can define molecular mechanisms through which variants underlying association signals exert their effects on disease

MONITORAGGIO DELL’ADERENZA ALLE PRATICHE DI IGIENE DELLE MANI DA PARTE DEL PERSONALE SANITARIO NEL POLICLINICO UMBERTO I DI ROMA

INTRODUZIONE: L’igiene delle mani tramite soluzione alcolica è da tempo riconosciuta come procedura efficace nel prevenire la trasmissione di agenti patogeni e di conseguenza ridurre l’incidenza delle Infezioni Correlate all’Assistenza. Ciononostante, l’adesione del personale sanitario alle pratiche di igiene delle mani rimane sempre piuttosto scarsa. Questo studio ha valutato l’aderenza alle raccomandazioni OMS sul lavaggio delle mani da parte del personale sanitario della UOC Anestesia e Rianimazione Centrale dell’Azienda Ospedaliera Universitaria Umberto I di Roma per quantificarne le percentuali ed eventualmente promuoverne un miglioramento. MATERIALI E METODI: Per un periodo di 6 mesi, quattro infermieri e due medici hanno eseguito osservazioni anonime delle attività svolte in reparto tramite la compilazione di un questionario elaborato secondo le linee guida OMS; tale questionario era focalizzato su quattro possibili interazioni tra il personale e i pazienti, con opportunità di lavaggio mani sia prima che dopo ogni interazione. Le percentuali di aderenza sono state descritte come il numero di lavaggi delle mani effettuati diviso il numero di opportunità. Il test del χ2 e il test sulle proporzioni sono stati utilizzati nell’analisi statistica. RISULTATI: Sono state raccolte un totale di 2274 opportunità di lavaggio delle mani. L’aderenza media complessiva è stata del 34,5%. L’aderenza al lavaggio mani dopo le interazioni con i pazienti è stata superiore a quella precedente le interazioni (p<0,001). In generale, sia infermieri che medici hanno registrato aderenze ugualmente scarse; anche prima delle procedure invasive, che richiedono un’efficace lavaggio asettica, le percentuali sono state similmente basse (19,1% vs 17,4%); l’aderenza degli infermieri è risultata invece significativamente superiore a quella dei medici dopo lo svolgimento di procedure invasive (74,7% vs 48,6%, p<0,001) o dopo la manipolazione di dispositivi utilizzati sui pazienti (58,0% vs 31,5%, p=0,001). CONCLUSIONI: Lo studio evidenzia una bassa aderenza alle pratiche di igiene delle mani in tutte le otto indicazioni indagate, particolarmente prima delle interazioni con il paziente. Allo scopo di migliorare l’aderenza, sono stati programmati incontri di condivisione dei risultati e formazione del personale con lo staff del reparto

Direct observation of hand hygiene compliance among healthcare workers in a teaching hospital of Rome

Background Hand hygiene with alcohol-based hand rub is widely recognized the most effective procedure to prevent pathogen cross-transmission and to control healthcare-associated infections. Unfortunately, adherence to WHO recommendations is often inadequate. This study evaluated hand hygiene compliance by direct observation in the main ICU unit of the “Umberto I” teaching hospital of Sapienza University of Rome to quantify hand hygiene compliance rates and to promote adherence to recommended practices. Methods For a 6-month period, four nurses and two physicians performed covert observations, filling out an anonymous questionnaire developed according to the WHO Guidelines for Hand Hygiene in Health-Care. The check sheet focused on four possible interactions between healthcare workers and patients, with hand hygiene opportunities before and after each interaction. Compliance rates were described as the number of hand rubs performed divided by the number of opportunities. χ2 test and two-sample test of proportions were used in the statistical analysis. Results We collected a total of 2274 hand hygiene opportunities. The average overall compliance was 34.5%. The proportion of compliance after interactions with patients was higher than before (p < 0.001). Generally, nurses’ and physicians’ compliance rates were similarly low with few professional behavioral differences; also before invasive procedures, which require the most effective aseptic technique, compliance rates were still low (19.1% vs 17.4%); instead, nurses’ compliance rates were significantly higher than physicians after invasive procedures (74.7% vs 48.6%, p < 0.001) or after device manipulations (58.0% vs 31.5%, p = 0.001). Conclusions The study shows a low hand hygiene compliance in all eight investigated indications, particularly before interactions. To improve the compliance rates, we scheduled feedback sessions with the ICU staff to highlight the importance of performing hand hygiene also before approaching patients

Role of a multimodal intervention to promote hand hygiene compliance among healthcare workers

Background: Hand hygiene with alcohol-based hand rub is widely recognized the most effective procedure to prevent pathogen cross-transmission and healthcare-associated infections; nevertheless, adherence to WHO recommendations is often inadequate. This study quantified hand hygiene compliance rates among healthcare workers in the main ICU unit of the “Umberto I” teaching hospital of Sapienza University of Rome, both before and after a multimodal intervention. Methods: From November 2016, three nurses and two physicians performed covert observations filling out an anonymous questionnaire developed according to the WHO Guidelines for Hand Hygiene in HealthCare. The check sheet focused on four possible interactions between healthcare workers and patients, with hand hygiene opportunities before and after each interaction. After six months, we conducted an educational intervention comprehensive of performance feedback sessions with the staff to discuss defective practices. For other twelve months, we continued to monitor their adherence. Results: We collected a total of 7908 hand hygiene opportunities, 2370 before the intervention and 5538 after. Generally, we recorded a statistically significant improvement in all the investigated indications. The average overall compliance increased from 34.3% to 61.6% (p &lt; 0.001). The compliance proportion before patient interactions increased from 19.0% to 42.8% (p &lt; 0.001) but remained still significantly lower than after the interactions (p &lt; 0.001). Hand hygiene opportunities after the patient interactions registered the highest adherence and raised from 49.6% to 80.4% (p &lt; 0.001). During all the 18 months, nurses compliance rates were always higher than physicians adherence. Conclusions: After conducting the multimodal intervention with the ICU staff to promote hand hygiene adherence, we recorded a significant improvement in all the investigated compliance rates even if, especially before approaching patients, they are still suboptimal

PI-RADS score v.2 in predicting malignancy in patients undergoing 5α-reductase inhibitor therapy

Background To investigate if the PI-RADS score represents an effective tool in detecting prostate cancer in patients treated with a 5 alpha-reductase inhibitor (dutasteride) and to identify dedicated total serum PSA and PSA density thresholds. Methods Between April 2015 and March 2018, 75 patients under dutasteride treatment underwent multi-parametric magnetic resonance imaging (mpMRI) scans and US/MRI fusion prostate biopsy. Lesions were classified into two groups: Group 1 included PI-RADS 4 and 5 lesions, whilst Group 2 included PI-RADS 3-4-5 lesions. Lesions in groups 1 and 2 were further divided according to the patients' history of previous prostate biopsy. Results Ninety-seven lesions were detected. In PI-RADS 4-5 group, mpMRI showed a sensitivity of 78.0% and a specificity of 78.7%. The positive predictive value (PPV) was 79.6% and the negative predictive value (NPV) 77.1%. In PI-RADS 3-4-5 group, sensitivity was 100%, specificity 21.3%, PPV 57.5%, NPV 100%. In PI-RADS 4-5 biopsy-naive group sensitivity was 71.4%, specificity 75.0%. PPV 78.9% and NPV 66.7%. In PI-RADS 4-5 non-biopsy-naive group sensitivity was 82.8%, specificity 80.6%, PPV 80%, and NPV 83.3%. PI-RADS 3-4-5 biopsy-naive group showed sensitivity 100%, specificity 31.3%, PPV 65.6%, NPV 100%. PI-RADS 3-4-5 non-biopsy-naive group showed sensitivity 100%, specificity 16.1%, PPV 52.7%, and NPV 100%. ROC curve analysis indicated a serum total PSA threshold of 6 ng/ml (AUC: 0.71-95% confidence interval: 0.60-0.81) and a PSA density &gt;0.22 (AUC: 0.70-95% confidence interval: 0.6-0.81) as optimal cut-offs for recommending prostate biopsy. Conclusions In our experience the PI-RADS score proved to be sufficiently accurate in predicting prostate cancer in patients under dutasteride therapy