Size effects on spheroidal voids by Finite Fracture Mechanics and application to corrosion pits

The present work aims at investigating the failure size effect of a spheroidal void in an infinite linear elastic solid under remote tension by means of the coupled Finite Fracture Mechanics (FFM) approach. The opening stress field and the stress intensity factor (SIF) of an annular crack surrounding the cavity -necessary for the FFM implementation- are obtained numerically through parametric axisymmetric finite element analyses (FEAs): The spheroid aspect ratio is varied between 0.1 and 10 and Poisson's ratio between 0.1 and 0.5. Accordingly, semi-analytical functions approximating the stress concentration factor and the SIF are put forward. Finally, the failure size effect on spheroidal voids is reported, and FFM predictions are compared with experimental results on the fatigue limit arising from corrosion pits, showing a fairly good agreement

How reproducible are methods to measure the dynamic viscoelastic properties of poroelastic media?

There is a considerable number of research publications on the acoustical properties of porous media with an elastic frame. A simple search through the Web of Science™ (last accessed 21 March 2018) suggests that there are at least 819 publications which deal with the acoustics of poroelastic media. A majority of these researches require accurate knowledge of the elastic properties over a broad frequency range. However, the accuracy of the measurement of the dynamic elastic properties of poroelastic media has been a contentious issue. The novelty of this paper is that it studies the reproducibility of some popular experimental methods which are used routinely to measure the key elastic properties such as the dynamic Young's modulus, loss factor and Poisson ratio of poroelastic media. In this paper, fourteen independent sets of laboratory measurements were performed on specimens of the same porous materials. The results from these measurements suggest that the reproducibility of this type of experimental method is poor. This work can be helpful to suggest improvements which can be developed to harmonize the way the elastic properties of poroelastic media are measured worldwide

Quantificazione della batteriuria e dei leucociti urinari mediante Sysmex UF-1000i: confronto con la coltura quantitativa

Le infezioni delle vie urinarie (UTI) sono assai comuni e di conseguenza le urine co-stituiscono il materiale processato pi\uf9 frequente-mente nella diagnostica microbiologica di routi-ne. Il gold standard diagnostico resta la coltura, tuttavia siccome gran parte dei campioni risulta-no negativi \ue8 auspicabile l'adozione di un effica-ce metodo di screening al fine di ridurre il nume-ro di esami colturali superflui. Metodi. Abbiamo valutato le performance anali-tiche e diagnostiche di un nuovo citometro urina-rio (Sysmex UF-1000i) in 209 campioni sottoposti ad uro coltura. Abbiamo comparato la conta dei batteri e dei leucociti urinari ottenuta con UF-1000i con i risultati della coltura quantitativa su CLED Agar a diversi cut-off. Risultati. Utilizzando, per la coltura quantitativa su CLED Agar un valore soglia a 10 4 Unit\ue0 For-manti Colonie (UFC) /mL per UF-1000i abbiamo ottenuto un cut-off di 30 batteri/microlitro e di 18 leucociti/microlitro; mentre utilizzando per la coltura quantitativa su CLED Agar un valore so-glia a 10 5 UFC/mL per UF-1000i abbiamo ottenu-to un cut-off di 125 batteri/microlitro e di 40 leu-cociti/microlitro. I parametri di Sensibilit\ue0 (SE), Specificit\ue0 (SP), Valore Predittivo Positivo (VPP), Valore Predittivo Negativo (VPN) sono sempre risultati soddisfacenti. Conclusioni. Gli autori, sulla base dei risultati ot-tenuti nel presente studio ritengono che nelle con-dizioni cliniche in cui si andrebbe ad utilizzare un valore soglia di 10 4 UFC/mL si possa raccoman-dare un cut-off, per UF-1000i di 30 batteri/micro-litro; cut off da portare a 125 batteri/microlitro per le condizioni cliniche ove si utilizzerebbe un valore soglia di 10 5 UFC/mL alla coltura quanti-tativa. La quantificazione dei leucociti urinari, nella diagnosi delle UTI mediante UF-1000i, sem-bra aggiungere poco all'utilizzo della sola batte-riuria

Laboratory diagnosis of renal failure: urine conductivity and tubular function.

AIM: Conductivity is a measure of a material's ability to conduct an electric current and it works thanks to movable charges. Conductivity in urine is directly proportional to ionic contents. The aim of this study was to evaluate the significance of urine conductivity by using the Sismex UF-100 analyser in correlations with other surrogate parameters of osmolality and renal diuresis, relative density, electrolytes and creatinine concentration. METHODS: For this study 140 urine samples were submitted for diagnostic urinalysis to the Clinical Pathology laboratory. Samples were collected from 70 healthy subjects, 42 diabetics with poor metabolic control and significant glicosuria, 28 patients with monoclonal gammopathy of uncertain significance, with significant proteinuria. All the samples were assessed for conductivity (UF-100 Sysmex), relative density (refract meter Zeiss), sodium, potassium, chlorine, creatinine, urea, glucose, protein (Olympus AU-2700). RESULTS: Urine conductivity appears to be related to ionic concentration but not to glucose and/or protein presence. CONCLUSIONS: This study results suggest that conductivity determination should be useful in diabetic patients to study the tubular function minimising interferences due to osmotic action of glucose

Cutoff values for bacteria and leukocytes for urine flow cytometer Sysmex UF-1000i in urinary tract infections.

Because urinary tract infections (UTIs) are a quite common disease, the gold standard for diagnosing UTIs is still bacterial culture, although a large percentage of samples are negative: unnecessary cultures can be reduced by means of an effective screening test. The analytic performance of a new urine cytometer, the UF-1000i, has been tested on 1463 urine samples submitted to our laboratory for culture. Bacteria and leukocyte counts have been compared by means of the UF-1000i with colony-forming unit (CFU) quantification on citrate lactose electrolytes deficient agar to assess the best cutoff values. By using quantitative cultures and considering as positive a sample with 10 x 10(5) CFU/mL, 546 positive samples (37%) were observed. If compared with 10 x 10(5) CFU/mL, the cutoff values obtained were 125 bacteria/microL and 40 leukocytes/ microL, respectively. Analytic parameters such as sensitivity, specificity, positive predictive value, negative predictive value, and correctly classified incidence were satisfactory. Based on the results obtained in this study, when using the UF-1000i analyzer for a screening test for UTI, a cutoff value of 40 white blood cells/microL should be adopted. The cutoff value for bacteria should be 125/microL for those clinical conditions in which 10 x 10(5) CFU/mL indicates a positivity

Urine particles examination: comparison of automated flow citometer UF-1000i and manual quantitative microscopy

Aim. Some automated instruments examining urine sediment have been introduced. We compared the performance of Sysmex UF-1000i with manual microscopy in urine particles examination. Methods. 15 urine samples were selected. Urine sediments were examined by manual microscopy by using Fuchs-Rosenthal chamber and UF-1000i analyzer. Results. The within-run CVs for urine samples ranged from 0.8% to 23.1% for the UF-1000i. The agreement between methods was good for red blood cells and white blood cells counts based on r values of 0.99, for epithelial cell the r value was 0.98 and 0.87 for casts. Conclusion. This automated urinalysis system demonstrated good concordance with manual quantitative microscopy. Thus, when combined with urine chemistry analysis, this analyzer might provide a rapid and accurate screening tool in routine urine analysis

Frequency of circulating CD4+Ki67+HLA-DR− T regulatory cells prior to treatment for multidrug resistant tuberculosis can differentiate the severity of disease and predict time to culture conversion

Identifying a blood circulating cellular biomarker that can be used to assess severity of disease and predict the time to culture conversion (TCC) in patients with multidrug resistant tuberculosis (MDR-TB) would facilitate monitoring response to treatment and may be of value in the design of future drug trials. We report on the frequency of blood Ki67+HLA-DR− CD4+ T regulatory (Treg) cells in predicting microbiological outcome before initiating second-line treatment for MDR-TB. Fifty-one patients with MDR-TB were enrolled and followed over 18 months; a subset of patients was sputum culture (SC) negative at baseline (n = 9). SC positive patients were divided into two groups, based on median TCC: rapid responders (≤71 days TCC; n = 21) and slow responders (>71 days TCC; n = 21). Whole blood at baseline, months 2 and 6 was stimulated with M tuberculosis (Mtb) antigens and Treg cells were then identified as CD3+CD4+CD25hiFoxP3+CD127−CD69− and further delineated as Ki67+HLA-DR− Treg. The frequency of these cells was significantly enlarged at baseline in SC positive relative to SC negative and smear positive relative to smear negative patients and in those with lung cavitation. This difference was further supported by unsupervised hierarchical clustering showing a significant grouping at baseline of total and early differentiated memory Treg cells in slow responders. Conversely, there was a clustering of a lower proportion of Treg cells and activated IFNg-expressing T cells at baseline in the rapid responders. Examining changes over time revealed a more gradual reduction of Treg cells in slow responders relative to rapid responders to treatment. Receiver operating curve analysis showed that baseline Mtb-stimulated Ki67+HLA-DR− Treg cells could predict the TCC of MDR-TB treatment response with 81.2%sensitivity and 85%specificity (AUC of 0.87, p < 0.0001), but this was not the case after 2months of treatment. In conclusion, our data show that the frequency of a highly defined Mtb-stimulated blood Treg cell population at baseline can discriminate MDR-TB disease severity and predict time to culture clearance.A National Institute of Allergy and Infectious Diseases grant (RO1 AI80737).http://www.frontiersin.org/Immunologyam2019Medical Microbiolog

Multiplexed imaging reveals an IFN-γ-driven inflammatory state in nivolumab-associated gastritis

Immune checkpoint blockade using PD-1 inhibition is an effective approach for treating a wide variety of cancer subtypes. While lower gastrointestinal (GI) side effects are more common, upper gastrointestinal adverse events are rarely reported. Here, we present a case of nivolumab-associated autoimmune gastritis. To elucidate the immunology underlying this condition, we leverage multiplexed ion beam imaging by time-of-flight (MIBI-TOF) to identify the presence and proportion of infiltrating immune cells from a single section of biopsy specimen. Using MIBI-TOF, we analyze formalin-fixed, paraffin-embedded human gastric tissue with 28 labels simultaneously. Our analyses reveal a gastritis characterized by severe mucosal injury, interferon gamma (IFN-γ)-producing gastric epithelial cells, and mixed inflammation that includes CD8 and CD4 T&nbsp;cell infiltrates with reduced expression of granzyme B and FOXP3, respectively. Here, we provide a comprehensive multiplexed histopathological mapping of gastric tissue, which identifies IFN-γ-producing epithelial cells as possible contributors to the nivolumab-associated gastritis

Key susceptibility locus for nonsyndromic cleft lip with or without cleft palate on chromosome 8q24

We conducted a genome-wide association study involving 224 cases and 383 controls of Central European origin to identify susceptibility loci for nonsyndromic cleft lip with or without cleft palate (NSCL/P). A 640-kb region at chromosome 8q24.21 was found to contain multiple markers with highly significant evidence for association with the cleft phenotype, including three markers that reached genome-wide significance. The 640-kb cleft-associated region was saturated with 146 SNP markers and then analyzed in our entire NSCL/P sample of 462 unrelated cases and 954 controls. In the entire sample, the most significant SNP (rs987525) had a P value of 3.34 x 10(-24). The odds ratio was 2.57 (95% CI = 2.02-3.26) for the heterozygous genotype and 6.05 (95% CI = 3.88-9.43) for the homozygous genotype. The calculated population attributable risk for this marker is 0.41, suggesting that this study has identified a major susceptibility locus for NSCL/P