708 research outputs found
Measles: An overview of a re-emerging disease in children and immunocompromised patients
Despite the availability of a safe and effective vaccine, in 2018, around 350,000 measles cases were reported worldwide, which resulted in an estimate of 142,300 deaths from measles. Additionally, in 2017, global measles cases spiked, causing the death of 110,000 people, mostly children under the age of 5 years and immunocompromised adults. The increase in measles incidence is caused by the ongoing reduction of vaccination coverage. This event has triggered public and scientific interest. For this reason, we reviewed the pathophysiology of measles infection, focusing on mechanisms by which the virus spreads systemically through the host organism. By reaching the lymphocytes from the airways through a \u201ctrojan horse\u201d strategy, measles induces an immunosuppression status. H and F glycoproteins, both expressed in the envelope, ensure attachment of the virus to host cells and spreading from one cell to another by binding to several receptors, as described in detail. The severity of the disease depends both on the age and underlying conditions of patients as well as the social and health context in which epidemics spread, and is often burdened by sequelae and complications that may occur several years after infection. Particular attention was paid to special groups that are more susceptible to severe or atypical measles. An overview of microbiology, symptoms, diagnosis, prevention, and treatment completes and enriches the review
Enteral and Parenteral Treatment with Caffeine for Preterm Infants in the Delivery Room: A Randomised Trial
Background: Early treatment with caffeine in the delivery room (DR) has been proposed to decrease the need for mechanical ventilation (MV) by limiting episodes of apnoea and improving respiratory mechanics in preterm infants. Our aim was to verify the hypothesis that intravenous or enteral administration of caffeine can be performed in the preterm infant in the DR. Methods: Infants with 25±0â29±6 weeks of gestational age were enrolled and randomised to receive 20 mg/kg of caffeine citrate intravenously, via the umbilical vein, or enterally, through an orogastric tube, within 10 min of birth. Caffeine blood level was measured at 60 ± 15 min after administration and 60 ± 15 min before the next dose (5 mg/kg). The primary endpoint was evaluation of the success rate of intravenous and enteral administration of caffeine in the DR. Results: Nineteen patients were treated with intravenous caffeine and 19 with enteral caffeine. In all patients the procedure was successfully performed. Peak blood level of caffeine 60 ± 15 min after administration in the DR was found to be below the therapeutic range (5 ”g/mL) in 25 % of samples and above the therapeutic range in 3%. Blood level of caffeine 60 ± 15 min before administration of the second dose was found to be below the therapeutic range in 18% of samples. Conclusions: Intravenous and enteral administration of caffeine can be performed in the DR without interfering with infantsâ postnatal assistance. Some patients did not reach the therapeutic range, raising the question of which dose is the most effective to prevent MV. Clinical Trial Registration: ClinicalTrials.gov identifier NCT04044976; EudraCT number 2018-003626-91
Pressure Induced Topological Phase Transitions in Membranes
Some highly unusual features of a lipid-water liquid crystal are revealed by
high pressure x-ray diffraction, light scattering and dilatometric studies of
the lamellar (bilayer ) to nonlamellar inverse hexagonal ()
phase transition. (i) The size of the unit cell of the phase increases
with increasing pressure. (ii) The transition volume, ,
decreases and appears to vanish as the pressure is increased. (iii) The
intensity of scattered light increases as decreases. Data are
presented which suggest that this increase is due to the formation of an
intermediate cubic phase, as predicted by recent theoretical suggestions of the
underlying universal phase sequence.Comment: 12 pages, typed using REVTEX 2.
Diffusion-weighted MRI radiomics of spine bone tumors: feature stability and machine learning-based classification performance
Purpose To evaluate stability and machine learning-based classification performance of radiomic features of spine bone tumors using diffusion- and T2-weighted magnetic resonance imaging (MRI). Material and methods This retrospective study included 101 patients with histology-proven spine bone tumor (22 benign; 38 primary malignant; 41 metastatic). All tumor volumes were manually segmented on morphologic T2-weighted sequences. The same region of interest (ROI) was used to perform radiomic analysis on ADC map. A total of 1702 radiomic features was considered. Feature stability was assessed through small geometrical transformations of the ROIs mimicking multiple manual delineations. Intraclass correlation coefficient (ICC) quantified feature stability. Feature selection consisted of stability-based (ICC > 0.75) and significance-based selections (ranking features by decreasing Mann-Whitney p-value). Class balancing was performed to oversample the minority (i.e., benign) class. Selected features were used to train and test a support vector machine (SVM) to discriminate benign from malignant spine tumors using tenfold cross-validation. Results A total of 76.4% radiomic features were stable. The quality metrics for the SVM were evaluated as a function of the number of selected features. The radiomic model with the best performance and the lowest number of features for classifying tumor types included 8 features. The metrics were 78% sensitivity, 68% specificity, 76% accuracy and AUC 0.78. Conclusion SVM classifiers based on radiomic features extracted from T2- and diffusion-weighted imaging with ADC map are promising for classification of spine bone tumors. Radiomic features of spine bone tumors show good reproducibility rates
Strong-Segregation Theory of Bicontinuous Phases in Block Copolymers
We compute phase diagrams for starblock copolymers in the
strong-segregation regime as a function of volume fraction , including
bicontinuous phases related to minimal surfaces (G, D, and P surfaces) as
candidate structures. We present the details of a general method to compute
free energies in the strong segregation limit, and demonstrate that the gyroid
G phase is the most nearly stable among the bicontinuous phases considered. We
explore some effects of conformational asymmetry on the topology of the phase
diagram.Comment: 14 pages, latex, 21 figures, to appear in Macromolecule
Long-lived photoexcited states in polydiacetylenes with different molecular and supramolecular organization
With the aim of determining the importance of the molecular and supramolecular organization on the excited states of polydiacetylenes, we have studied the photoinduced absorption spectra of the red form of poly[1,6-bis(3,6-didodecyl-N-carbazolyl)-2,4-hexadiyne] (polyDCHD-S) and the results compared with those of the blue form of the same polymer. An interpretation of the data is given in terms of both the conjugation length and the interbackbone separation also in relation to the photoinduced absorption spectra of both blue and red forms of poly[1,6-bis(N-carbazolyl)-2,4-hexadiyne] (polyDCHD), which does not carry the alkyl substituents on the carbazolyl side groups. Information on the above properties is derived from the analysis of the absorption and Raman spectra of this class of polydiacetylenes
High SPARC expression starting from dysplasia, associated with breast carcinoma, is predictive for bone metastasis without enhancement of plasma levels
In order to become established in the skeleton, metastatic cells disseminating from the breast carcinoma need to acquire organ-specific traits. There are no effective predictors for who will develop bone metastasis to guide long-term predictive therapy. Our purpose was to individuate events critical for bone colonization to make a molecular classification of breast carcinoma useful for bone-metastasis outcome. In dysplasia adjacent to carcinoma and in pair-matched specimens of bone metastasis we examined SPARC expression and localization as well as Endothelin 1/ETAR signals by immunohistochemistry, and the evaluation of plasma levels of SPARC by ELISA was also performed. In patients with breast carcinoma metastasizing to bone, SPARC and Endothelin 1/ETAR axis were highly expressed from dysplasia until bone metastasis, but the SPARC plasma level was as low as that of normal women, in contrast to patients that never develop bone metastasis, suggesting that circulating SPARC was counter adhesive. Altogether, the early identification of SPARC/Endothelin 1/ETAR in dysplastic lesions would be important to devise therapies preventing metastasis engraftment, since often carcinoma cells spread to distant organs at the time or even before patients present with cancer
3D vs. 2D MRI radiomics in skeletal Ewing sarcoma: Feature reproducibility and preliminary machine learning analysis on neoadjuvant chemotherapy response prediction
ObjectiveThe extent of response to neoadjuvant chemotherapy predicts survival in Ewing sarcoma. This study focuses on MRI radiomics of skeletal Ewing sarcoma and aims to investigate feature reproducibility and machine learning prediction of response to neoadjuvant chemotherapy. Materials and methodsThis retrospective study included thirty patients with biopsy-proven skeletal Ewing sarcoma, who were treated with neoadjuvant chemotherapy before surgery at two tertiary sarcoma centres. 7 patients were poor responders and 23 were good responders based on pathological assessment of the surgical specimen. On pre-treatment T1-weighted and T2-weighted MRI, 2D and 3D tumour segmentations were manually performed. Features were extracted from original and wavelet-transformed images. Feature reproducibility was assessed through small geometrical transformations of the regions of interest mimicking multiple manual delineations, and intraclass correlation coefficient >0.75 defined feature reproducibility. Feature selection also consisted of collinearity and significance analysis. After class balancing in the training cohort, three machine learning classifiers were trained and tested on unseen data using hold-out cross-validation. Results1303 (77%) 3D and 620 (65%) 2D radiomic features were reproducible. 4 3D and 4 2D features passed feature selection. Logistic regression built upon 3D features achieved the best performance with 85% accuracy (AUC=0.9) in predicting response to neoadjuvant chemotherapy. ConclusionCompared to 2D approach, 3D MRI radiomics of Ewing sarcoma had superior reproducibility and higher accuracy in predicting response to neoadjuvant chemotherapy, particularly when using logistic regression classifier
Ceftolozane/tazobactam for the treatment of serious Pseudomonas aeruginosa infections: a multicentre nationwide clinical experience
This study describes the largest clinical experience using ceftolozane/tazobactam (C/T) for different Pseudomonas aeruginosa infections. A retrospective study was performed at 22 hospitals in Italy (June 2016\u2013March 2018). All adult patients treated with 654 days of C/T were enrolled. Successful clinical outcome was defined as complete resolution of clinical signs/symptoms related to P. aeruginosa infection and lack of microbiological evidence of infection. C/T treatment was documented in 101 patients with diverse infections, including nosocomial pneumonia (31.7%), acute bacterial skin and skin-structure infection (20.8%), complicated UTI (13.9%), complicated IAI (12.9%), bone infection (8.9%) and primary bacteraemia (5.9%). Over one-half of P. aeruginosa strains were XDR (50.5%), with 78.2% of isolates resistant to at least one carbapenem. C/T was used as first-line therapy in 39 patients (38.6%). When used as second-line or later, the most common reasons for discontinuation of previous antibiotics were in vitro resistance of P. aeruginosa and clinical failure of previous therapy. Concomitant antibiotics were reported in 35.6% of patients. C/T doses were 1.5 g q8h in 70 patients (69.3%) and 3 g q8h in 31 patients (30.7%); median duration of C/T therapy was 14 days. Overall clinical success was 83.2%. Significant lower success rates were observed in patients with sepsis or receiving continuous renal replacement therapy (CRRT). Mild adverse events were reported in only three patients. C/T demonstrated a favourable safety and tolerability profile regardless of the infection type. Clinicians should be aware of the risk of clinical failure with C/T therapy in septic patients receiving CRRT
Reactivation of Herpes Simplex Virus Type 1 (HSV-1) Detected on Bronchoalveolar Lavage Fluid (BALF) Samples in Critically Ill COVID-19 Patients Undergoing Invasive Mechanical Ventilation: Preliminary Results from Two Italian Centers
Reactivation of herpes simplex virus type 1 (HSV-1) has been described in critically ill patients with coronavirus disease 2019 (COVID-19) pneumonia. In the present two-center retrospective experience, we primarily aimed to assess the cumulative risk of HSV-1 reactivation detected on bronchoalveolar fluid (BALF) samples in invasively ventilated COVID-19 patients with worsening respiratory function. The secondary objectives were the identification of predictors for HSV-1 reactivation and the assessment of its possible prognostic impact. Overall, 41 patients met the study inclusion criteria, and 12/41 patients developed HSV-1 reactivation (29%). No independent predictors of HSV-1 reactivation were identified in the present study. No association was found between HSV-1 reactivation and mortality. Eleven out of 12 patients with HSV-1 reactivation received antiviral therapy with intravenous acyclovir. In conclusion, HSV-1 reactivation is frequently detected in intubated patients with COVID-19. An antiviral treatment in COVID-19 patients with HSV-1 reactivation and worsening respiratory function might be considered
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