Reconstructing the free energy landscape of a polyprotein by single-molecule experiments

The mechanical unfolding of an engineered protein composed of eight domains of Ig27 is investigated by using atomic force microscopy. Exploiting a fluctuation relation, the equilibrium free energy as a function of the molecule elongation is estimated from pulling experiments. Such a free energy exhibits a regular shape that sets a typical unfolding length at zero force of the order of 20 nm. This length scale turns out to be much larger than the kinetic unfolding length that is also estimated by analyzing the typical rupture force of the molecule under dynamic loading

Carbapenem-Sparing Antibiotic Regimens for Infections Caused by Klebsiella pneumoniae Carbapenemase-Producing K. pneumoniae in Intensive Care Unit

A carbapenem-sparing regimen of tigecycline plus gentamicin or colistin was effective for treating 24 of 26 (92%) Klebsiella pneumoniae carbapenemase-producing K. pneumoniae infectious episodes in 22 polytrauma intensive care unit patients without comorbidities. The 30-day crude mortality rate was 14%. Regimens were considered appropriate in 12% of episodes according to the Vitek 2 System and in 100% based on E-test

Mechanical and Electrophysiological Properties of the Sarcolemma of Muscle Fibers in Two Murine Models of Muscle Dystrophy: Col6a1−/− and Mdx

This study aimed to analyse the sarcolemma of Col6a1−/− fibers in comparison with wild type and mdx fibers, taken as positive control in view of the known structural and functional alterations of their membranes. Structural and mechanical properties were studied in single muscle fibers prepared from FDB muscle using atomic force microscopy (AFM) and conventional electrophysiological techniques to measure ionic conductance and capacitance. While the sarcolemma topography was preserved in both types of dystrophic fibers, membrane elasticity was significantly reduced in Col6a1−/− and increased in mdx fibers. In the membrane of Col6a1−/− fibers ionic conductance was increased likely due to an increased leakage, whereas capacitance was reduced, and the action potential (ap) depolarization rate was reduced. The picture emerging from experiments on fibers in culture was consistent with that obtained on intact freshly dissected muscle. Mdx fibers in culture showed a reduction of both membrane conductance and capacitance. In contrast, in mdx intact FDB muscle resting conductance was increased while resting potential and ap depolarization rate were reduced, likely indicating the presence of a consistent population of severely altered fibers which disappear during the culture preparation

CYP17A1 polymorphism c.-362T>C predicts clinical outcome in metastatic castration-resistance prostate cancer patients treated with abiraterone

Background: Abiraterone became a standard hormonal therapy for patients with metastatic castration-resistance prostate cancer (mCRPC). However, patients may experience primary resistance to treatment. To date, few predictive biomarkers of efficacy have been identified. Our aim was to investigate the association between the single nucleotide polymorphism (SNP) c.-362T>C in the CYP17A1 gene, and clinical outcome in mCRPC patients treated with abiraterone. Patients and methods: mCRPC patients candidate to receive abiraterone were enrolled in the present retrospective pharmacogenetic study. Based on a literature selection, CYP17A1 rs2486758 (c.-362T > C) was selected and analysed by real-time PCR on genomic DNA extracted from whole blood. Univariate analysis was performed to test the association between the SNP and treatment-related clinical outcomes. Results: Sixty mCRPC patients were enrolled in the present study. Patients carrying the mutant CYP17A1 c.-362CT/CC genotypes showed a shorter median progression-free survival (PFS) and prostate-specific antigen-PFS (PSA-PFS) compared to patients carrying the TT genotype (10.7 vs 14.2 months and 8 vs 16 months, respectively; p = 0.04). No association between the selected SNP and the overall survival was found. Conclusions: These findings suggest an association between CYP17A1 c.-362T>C polymorphism and poorer clinical outcome with abiraterone for mCRPC patients. However, further validations on larger cohort of patients are needed to confirm its role as a predictive biomarker for abiraterone resistance

Contrasting effects of cover crops on 'hot spot' arbuscular mycorrhizal fungal communities in organic tomato

Arbuscular mycorrhizal fungal (AMF) communities are fundamental in organic cropping systems where they provide essential agro-ecosystem services, improving soil fertility and sustaining crop production. They are affected by agronomic practices, but still, scanty information is available about the role of specific crops, crop rotations and the use of winter cover crops on the AMF community compositions at the field sites. A field experiment was conducted to elucidate the role of diversified cover crops and AMF inoculation on AMF diversity in organic tomato. Tomato, pre-inoculated at nursery with two AMF isolates, was grown following four cover crop treatments: Indian mustard, hairy vetch, a mixture of seven species and a fallow. Tomato root colonization at flowering was more affected by AMF pre-transplant inoculation than by the cover crop treatments. An enormous species richness was found by morphological spore identification: 58 AMF species belonging to 14 genera, with 46 and 53 species retrieved at the end of cover crop cycle and at tomato harvest, respectively. At both sampling times, AMF spore abundance was highest in hairy vetch, but after tomato harvest, AMF species richness and diversity were lower in hairy vetch than in the cover crop mixture and in the mustard treatments. A higher AMF diversity was found at tomato harvest, compared with the end of the cover crop cycle, independent of the cover crop and pre-transplant AMF inoculation. Our findings suggest that seasonal and environmental factors play a major role on AMF abundance and diversity than short-term agronomic practices, including AMF inoculation. The huge AMF diversity is explained by the field history and the Mediterranean environment, where species characteristic of temperate and sub-tropical climates co-occur

MAGLIO study: epideMiological Analysis on invasive meninGococcaL disease in Italy: fOcus on hospitalization from 2015 to 2019

This study analyzed hospital admissions for invasive meningococcal disease (IMD) in epidemiological and economic terms in Italy from 2015 to 2019. The volume of acute admissions for meningococcal diagnosis was analyzed in the period from 2015 to 2019. IMD admissions were identified by ICD-9-CM diagnoses. Costs were assessed using current DRG tariffs. In 2019, a total of 237 admissions for meningococcal disease were recorded in Italy. The mean age of patients was 36.1 years. Lumbar puncture was reported in only 14% of hospital discharge forms. From 2015 to 2019, there was a mean annual reduction of - 1.2% nationally for IMD hospitalizations. For 2019, the total costs for acute inpatient admissions were euro2,001,093. Considering annual incidence due to IMD, a significant decrease was noted in the age group from 0 to 1 year (p = 0.010) during 2015-2019. For all years, mortality associated with meningeal syndrome was lower compared to septic shock with or without meningitis. From 2015 to 2019, hospitalizations for IMD appear to be decreasing slightly in Italy, even if mortality remains high. Favorable trends in hospitalizations for IMD were seen in the 0-1-year age group, which may be attributable to increased vaccination. Costs of hospitalizations for IMD remain high

Recognition in emergency department of septic patients at higher risk of death: Beware of patients without fever

Background and Objectives: Chances of surviving sepsis increase markedly upon prompt diagnosis and treatment. As most sepsis cases initially show-up in the Emergency Department (ED), early recognition of a septic patient has a pivotal role in sepsis management, despite the lack of precise guidelines. The aim of this study was to identify the most accurate predictors of in-hospital mortality outcome in septic patients admitted to the ED. Materials and Methods: We compared 651 patients admitted to ED for sepsis (cases) with 363 controls (non-septic patients). A Bayesian mean multivariate logistic regression model was performed in order to identify the most accurate predictors of in-hospital mortality outcomes in septic patients. Results: Septic shock and positive qSOFA were identified as risk factors for in-hospital mortality among septic patients admitted to the ED. Hyperthermia was a protective factor for in-hospital mortality. Conclusions: Physicians should bear in mind that fever is not a criterium for defining sepsis; according to our results, absence of fever upon presentation might be indicative of greater severity and diagnosis of sepsis should not be delayed

Honeybee-collected pollen for human consumption: impact of post-harvest conditioning on the microbiota

Bee pollen is gaining attention as functional food for human consumption. However, scanty information is available on the effects of post-harvest conditioning methods on microbial populations associated to bee pollen. Here, we assessed the microbiological quality and safety of bee-collected chestnut and willow pollen processed by different treatments, such as conventional, freeze- and microwave-assisted drying. Conventional drying of chestnut pollen significantly reduced the abundance of aerobic mesophilic bacteria and the contamination by enterobacteria and yeasts. No impact of freeze-drying and microwave-assisted conditioning was found on hygiene indicators. In chestnut pollen, microwave-assisted drying effectively reduced aerobic sporeforming bacteria, while all conditioning treatments strongly decreased coagulase-positive staphylococci. None of the conditioning methods allowed the reduction of moulds contamination and the abundance of sulphite-reducing clostridia. Our findings stress the importance of studying the microbiota of bee-collected pollen for human consumption, in order to process safe pollen with high microbiological quality