38 research outputs found

    Growth history and quasar bias evolution at z < 3 from Quaia

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    We make use of the Gaia-unWISE quasar catalogue, Quaia, to constrain the growth history out to high redshifts from the clustering of quasars and their cross-correlation with maps of the Cosmic Microwave Background (CMB) lensing convergence. Considering three tomographic bins, centred at redshifts z̅i = [0.69, 1.59, 2.72], we reconstruct the evolution of the amplitude of matter fluctuations σ 8(z) over the last ∼ 12 billion years of cosmic history. In particular, we make one of the highest-redshift measurements of σ 8 (σ 8(z = 2.72) = 0.22 ± 0.06), finding it to be in good agreement (at the ∼ 1σ level) with the value predicted by ΛCDM using CMB data from Planck. We also used the data to study the evolution of the linear quasar bias for this sample, finding values similar to those of other quasar samples, although with a less steep evolution at high redshifts. Finally, we study the potential impact of foreground contamination in the CMB lensing maps and, although we find evidence of contamination in cross-correlations at z ∼ 1.7 we are not able to clearly pinpoint its origin as being Galactic or extragalactic. Nevertheless, we determine that the impact of this contamination on our results is negligible

    Monitoring of cytomegalovirus (CMV) infection in solid organ transplant recipients: quantitation of CMV DNAemia by two real-time polymerase chain reaction assays

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    Background and aim: Quantification of cytomegalovirus (CMV) DNAemia is essential in clinical management of post-transplant infection. We evaluated the performances of two quantitative real-time polymerase chain reaction (PCR) assays. Materials and Methods: 114 serial whole blood samples collected from 14 actively infected transplant recipients were processed by Abbott RealTime CMV PCR kit (Abbott Molecular) and CMV ELITe MGB™ kit (ELITech Group). The Quality Control for Molecular Diagnostics human CMV panels was also tested. Results: Sixteen (14%) samples resulted negative and 59 (51.7%) positive with a quantitative result for both assays. In the 59 samples, the coefficient of correlation was 0.856. Bland-Altman analysis showed a mean difference of &lt;0.11 log10 copies/mL (standard deviation=0.38 log10 copies/mL). The assays gave CMV-DNA loads differing by 1 log10 DNA copies/mL in 57 samples (96.6%) and by &lt;0.5 log10 DNA copies/mL in 48 samples (81.3%). Eleven (9.6%) samples were positive with a quantitative result with Abbott and negative with ELITech. Sixteen (14%) positive samples with a quantitative result for Abbott resulted positive but below the lower limit of quantification (LLQ) for ELITech. Twelve (10.5%) samples resulted negative with ELITech and positive but below the LLQ with Abbott. No samples were positive with ELITech and negative with Abbott. Conclusions: The assays showed a good correlation between CMVDNA levels detected and variation in CMV-DNA &lt;0.5 log10 was observed in the majority of the samples. The viral load kinetic profiles of the assays were overlapping in all patients, but Abbott showed higher sensitivity in samples containing lower amount of DNA. The clinical value of this greater sensitivity requires further investigation

    Kinetics of cytomegalovirus and Epstein-Barr virus DNA in whole blood and plasma of kidney transplant recipients: Implications on management strategies

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    This retrospective multicenter cohort study investigated the kinetics (ascending and descending phases) of cytomegalovirus (CMV) and Epstein-Barr virus (EBV)-DNA in whole blood (WB) and plasma samples collected from adult kidney transplant (KT) recipients. CMV-DNA kinetics according to antiviral therapy were investigated. Three hundred twenty-eight paired samples from 42 episodes of CMV infection and 157 paired samples from 26 episodes of EBV infection were analyzed by a single commercial molecular method approved by regulatory agencies for both matrices. CMV-DNAemia followed different kinetics in WB and plasma. In the descending phase of infection, a slower decay of viral load and a higher percentage of CMV-DNA positive samples were observed in plasma versus WB. In the 72.4% of patients receiving antiviral therapy, monitoring with plasma CMV-DNAemia versus WB CMV-DNAemia could delay treatment interruption by 7-14 days. Discontinuation of therapy based on WB monitoring did not result in relapsed infection in any patients. Highly different EBV-DNA kinetics in WB and plasma were observed due to lower positivity in plasma; EBV positive samples with a quantitative result in both blood compartments were observed in only 11.5% of cases. Our results emphasize the potential role of WB as specimen type for post-KT surveillance of both infections for disease prevention and management

    Measles outbreaks in the Emilia-Romagna Region, Italy, during 2016

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    Background and aim. Despite the availability of a vaccine,measles continues to be endemic in Italy, where an increase of cases was reported during 2016. This study describes the measles outbreaks in Emilia-Romagna Region (ERR), one of the Italian regions mostly affected. Materials and Methods. A total of 101 suspected cases were reported in ERR during 2016. Laboratory diagnosis by serological and/or molecular methods was performed on 142 specimens (78 urine, 19 oral fluid and 45 sera) related to 97 suspected cases. For positive cases, measles virus (MV) strains involved were identified. Results. Among 101 suspected cases, 72 (71.3%) were confirmed. Vaccination status was known for 61 (84.7%) cases, of which 56 (91.8%) were unvaccinated. The highest incidence was found in the age group 15-39 years. In addition, for the 34.7% (25/72) of confirmed cases, the transmission occurred in nosocomial settings, where healthcare workers were involved (60% of cases). Roma/Sinti population were also involved in 12.5% (9/72)or confirmed cases. Both groups are considered hard-to-reach for immunization. The phylogenetic analysis showed circulation of MV strains belonging to genotype B3 and D8 in 45 (80.4%) and 11 cases (19.6%), respectively. In 94.7% of cases, the measles endemic transmission was demonstrated. Conclusions. This data obtained through active surveillance showed the endemic transmission of MV within a population with immunity gaps including healthcare workers (20.8% of confirmed cases), among which the spread of two endemic MV strains was observed

    On the lookout for influenza viruses in Italy during the 2021-2022 season: along came A(H3N2) viruses with a new phylogenetic makeup of their hemagglutinin

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    Aims: To assess influenza viruses (IVs) circulation and to evaluate A(H3N2) molecular evolution during the 2021-2022 season in Italy. Materials and methods: 12,393 respiratory specimens (nasopharyngeal swabs or broncho-alveolar lavages) collected from in/outpatients with influenza illness in the period spanning from January 1, 2022 (week 2022-01) to May 31, 2022 (week 2022-22) were analysed to identify IV genome and molecularly characterized by 12 laboratories throughout Italy. A(H3N2) evolution was studied by conducting an in-depth phylogenetic analysis of the hemagglutinin (HA) gene sequences. The predicted vaccine efficacy (pVE) of vaccine strain against circulating A(H3N2) viruses was estimated using the sequence-based Pepitope model. Results: The overall IV-positive rate was 7.2% (894/12,393), all were IV type A. Almost all IV-A (846/894; 94.6%) were H3N2 that circulated in Italy with a clear epidemic trend, with 10% positivity rate threshold crossed for six consecutive weeks from week 2022-11 to week 2022-16. According to the phylogenetic analysis of a subset of A(H3N2) strains (n=161), the study HA sequences were distributed into five different genetic clusters, all of them belonging to the clade 3C.2a, sub-clade 3C.2a1 and the genetic subgroup 3C.2a1b.2a.2. The selective pressure analysis of A(H3N2) sequences showed evidence of diversifying selection particularly in the amino acid position 156. The comparison between the predicted amino acid sequence of the 2021-2022 vaccine strain (A/Cambodia/e0826360/2020) and the study strains revealed 65 mutations in 59 HA amino acid positions, including the substitution H156S and Y159N in antigenic site B, within major antigenic sites adjacent to the receptor-binding site, suggesting the presence of drifted strains. According to the sequence-based Pepitope model, antigenic site B was the dominant antigenic site and the p(VE) against circulating A(H3N2) viruses was estimated to be -28.9%. Discussion and conclusion: After a long period of very low IV activity since public health control measures have been introduced to face COVID-19 pandemic, along came A(H3N2) with a new phylogenetic makeup. Although the delayed 2021-2022 influenza season in Italy was characterized by a significant reduction of the width of the epidemic curve and in the intensity of the influenza activity compared to historical data, a marked genetic diversity of circulating A(H3N2) strains was observed. The identification of the H156S and Y159N substitutions within the main antigenic sites of the most of sequences also suggested the circulation of drifted variants with respect to the 2021-2022 vaccine strain. Molecular surveillance plays a critical role in the influenza surveillance architecture and it has to be strengthened also at local level to timely assess vaccine effectiveness and detect novel strains with potential impact on public health

    Unraveling the impact of upfront chemotherapy and proton beam therapy on treatment outcome and follow-up in central nervous system germ cell tumors: a single center experience

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    BackgroundGerm cell tumors (GCT) account for a minority of central nervous system (CNS) malignancies, highly prevalent in adolescents and young adults. Despite their aggressive biological behavior, prognosis is excellent in most cases with risk stratified treatment, consisting in a combination of chemotherapy and radiotherapy. Whole ventricular irradiation (WVI) and craniospinal irradiation, the treatment of choice for localized and metastatic disease, pose significant risk of collateral effects, therefore proton beam radiation (PBT) has been recently proposed for its steep dose fallout.Materials and methodsWe report our experience in a consecutive series of 17 patients treated for CNS GCT at our Institution from 2015 to 2021.ResultsMost frequent lesion location were sellar/suprasellar (35%) and bifocal germinoma (35%), followed by pineal (18%) and thalamic (12%). Two patients (12%), had evidence of disseminated disease at the time of diagnosis. At the latest follow-up all but one patient showed complete response to treatment. The only relapse was successfully rescued by additional chemotherapy and PBT. PBT was well tolerated in all cases. No visual, neurological or endocrinological worsening was documented during and after treatment. Neuropsychological evaluation demonstrated preservation of cognitive performance after PBT treatment.ConclusionsOur data, albeit preliminary, strongly support the favourable therapeutic profile of PBT for the treatment of CNS germ cell tumors

    Human congenital cytomegalovirus infection: characteristics and pathogenesis of fetal brain damage

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    Human cytomegalovirus (HCMV) causes congenital neurological lifelong disabilities. The study analyzed 10 HCMV-infected human fetuses at 21 weeks of gestation to evaluate the characteristics and pathogenesis of brain injury related to congenital human CMV (cCMV) infection. Specifically, tissues from cortical and white matter areas, subventricular zone, thalamus, hypothalamus, hippocampus, basal ganglia and cerebellum were analysed by: i) immunohistochemistry (IHC) to detect HCMV-infected cell distribution, ii) hematoxylin-eosin staining to evaluate histological damage and iii) real-time PCR to quantify tissue viral load (HCMV-DNA). Viral tropism was assessed by double IHC to detect HCMV-antigens and neural/neuronal markers: nestin (expressed in early differentiation stage), doublecortin (DCX, identifying neuronal precursor cells) and neuronal nuclei (NeuN, identifying mature neurons). HCMV-positive cells and viral DNA were found in the brain of 8/10 (80%) fetuses. For these cases, brain damage was classified in mild (n=4, 50%), moderate (n=3, 37.5%) and severe (n=1, 12.5%) based on presence of i) diffuse astrocytosis, microglial activation and vascular changes; ii) occasional (in mild) or multiple (in moderate/severe) microglial nodules and iii) necrosis (in severe). The highest median HCMV-DNA level was found in the hippocampus (212 copies/5ng of humanDNA [hDNA], range: 10-7,505) as well as the highest mean HCMV-infected cell value (2.9 cells, range: 0-23), followed by that detected in subventricular zone (1.8 cells, range: 0-19). This suggests a preferential HCMV tropism for immature neuronal cells, residing in these regions, confirmed by the detection of DCX and nestin in 94% and 63.3% of HCMV-positive cells, respectively. NeuN was not found among HCMV-positive cells and was nearly absent in the brain with severe damage, suggesting HCMV does not infect mature neurons and immature HCMV-infected neuronal cells do not differentiate into neurons. HCMV preferential tropism in immature neural/neuronal cells delays/inhibits their differentiation interfering with brain development processes that lead to structural and functional brain defects

    Diagnosis and monitoring of cytomegalovirus infection by the quantification of viral load in dried blood spots samples

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    Cytomegalovirus (CMV) represents the major infectious cause of birth defects, as well as an important pathogen for immune-compromised individuals. Several studies described the use of dried blood spots (DBS) for the detection of CMV DNA for late diagnosis of congenital CMV infection in cases of strong clinical suspicion. In the article under evaluation, Limaye et al. perform for the first time the quantification of CMV in pairs of finger-stick DBS and plasma samples collected from transplant patients. The work concluded that finger-stick DBS could be an alternative sample type for quantification of CMV load that correlates well with plasma levels. Prospective trials to evaluate the use of DBS for monitoring CMV load in transplant recipients will be required

    Antimicrobial Efficacy of Five Probiotic Strains Against Helicobacter Pylori

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    Treatment ofHelicobacter pylori(H. pylori) infection is a challenge for clinicians. The largeincrease in drug-resistant strains makes the formulation of new therapeutic strategies fundamental.The frequent onset of side effects during antibiotic treatment (mainly due to intestinal dysbiosis)should not be underestimated as it may cause the interruption of treatment, failure ofH. pylorieradication and clonal selection of resistant bacteria. Probiotic integration during antibiotic treatmentcan exert a dual function: a direct antagonistic effect onH. pyloriand a balancing effect on dysbiosis.Therefore, it fulfills the definition of a new therapeutic strategy to successfully treatH. pyloriinfection.Data reported in literature give promising but discrepant results. Aim: To assessin vitrobacteriostaticand bactericidal activity of probiotic strains againstH. pylori. Materials and methods:L. casei, L.paracasei, L. acidophilus, B. lactisandS. thermophilusstrains were used. Agar well diffusion and time-killcurves were carried out to detect bacteriostatic and bactericidal activity, respectively. Results: Allprobiotic strains showed both bacteriostatic and bactericidal activity vs.H. pylori. Conclusions: Suchfindings prompted us to plan a protocol of treatment in which probiotics are given to infected patientsin association with antibiotic therapy

    Growth history and quasar bias evolution at z < 3 from Quaia

    No full text
    We make use of the Gaia-unWISE quasar catalogue, Quaia, to constrain the growth history out to high redshifts from the clustering of quasars and their cross-correlation with maps of the Cosmic Microwave Background (CMB) lensing convergence. Considering three tomographic bins, centred at redshifts z̅i = [0.69, 1.59, 2.72], we reconstruct the evolution of the amplitude of matter fluctuations σ 8(z) over the last ∼ 12 billion years of cosmic history. In particular, we make one of the highest-redshift measurements of σ 8 (σ 8(z = 2.72) = 0.22 ± 0.06), finding it to be in good agreement (at the ∼ 1σ level) with the value predicted by ΛCDM using CMB data from Planck. We also used the data to study the evolution of the linear quasar bias for this sample, finding values similar to those of other quasar samples, although with a less steep evolution at high redshifts. Finally, we study the potential impact of foreground contamination in the CMB lensing maps and, although we find evidence of contamination in cross-correlations at z ∼ 1.7 we are not able to clearly pinpoint its origin as being Galactic or extragalactic. Nevertheless, we determine that the impact of this contamination on our results is negligible
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