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41.
With the aim of presenting the processes governing the Laser-Induced Periodic Surface Structures (LIPSS), its main theoretical models have been reported. More emphasis is given to those suitable for clarifying the experimental structures observed on the surface of wide bandgap semiconductors (WBS) and dielectric materials. The role played by radiation surface electromagnetic waves as well as Surface Plasmon Polaritons in determining both Low and High Spatial Frequency LIPSS is briefly discussed, together with some experimental evidence. Non-conventional techniques for LIPSS formation are concisely introduced to point out the high technical possibility of enhancing the homogeneity of surface structures as well as tuning the electronic properties driven by point defects induced in WBS. Among these, double- or multiple-fs-pulse irradiations are shown to be suitable for providing further insight into the LIPSS process together with fine control on the formed surface structures. Modifications occurring by LIPSS on surfaces of WBS and dielectrics display high potentialities for their cross-cutting technological features and wide applications in which the main surface and electronic properties can be engineered. By these assessments, the employment of such nanostructured materials in innovative devices could be envisaged.  相似文献   
42.

The development of vaccines to prevent SARS-CoV-2 infection has mainly relied on the induction of neutralizing antibodies (nAbs) to the Spike protein of SARS-CoV-2, but there is growing evidence that T cell immune response can contribute to protection as well. In this study, an anti-receptor binding domain (RBD) antibody assay and an INFγ-release assay (IGRA) were used to detect humoral and cellular responses to the Pfizer-BioNTech BNT162b2 vaccine in three separate cohorts of COVID-19-naïve patients: 108 healthcare workers (HCWs), 15 elderly people, and 5 autoimmune patients treated with immunosuppressive agents. After the second dose of vaccine, the mean values of anti-RBD antibodies (Abs) and INFγ were 123.33 U/mL (range 27.55–464) and 1513 mIU/mL (range 145–2500) in HCWs and 210.7 U/mL (range 3–500) and 1167 mIU/mL (range 83–2500) in elderly people. No correlations between age and immune status were observed. On the contrary, a weak but significant positive correlation was found between INFγ and anti-RBD Abs values (rho = 0.354, p = 0.003). As to the autoimmune cohort, anti-RBD Abs were not detected in the two patients with absent peripheral CD19+B cells, despite high INFγ levels being observed in all 5 patients after vaccination. Even though the clinical relevance of T cell response has not yet been established as a correlate of vaccine-induced protection, IGRA testing has showed optimal sensitivity and specificity to define vaccine responders, even in patients lacking a cognate antibody response to the vaccine.

  相似文献   
43.
Mechanisms of exercise-induced muscle injury with etiopathogenesis and its consequences have been described; however, the impact of different intensities of exercise on the mechanisms of muscular injury development is not well understood. The aim of this study was to exploit the relationship between platelet activation, oxidative stress and muscular injuries induced by physical exercise in elite football players compared to amateur athletes. Oxidant/antioxidant status, platelet activation and markers of muscle damage were evaluated in 23 elite football players and 23 amateur athletes. Compared to amateurs, elite football players showed lower antioxidant capacity and higher oxidative stress paralleled by increased platelet activation and muscle damage markers. Simple linear regression analysis showed that sNOX2-dp and H2O2, sCD40L and PDGF-bb were associated with a significant increase in muscle damage biomarkers. In vitro studies also showed that plasma obtained from elite athletes increased oxidative stress and muscle damage in human skeletal muscle myoblasts cell line compared to amateurs’ plasma, an effect blunted by the NOX2 inhibitor or by the cell treatment with cocoa-derived polyphenols. These results indicate that platelet activation increased muscular injuries induced by oxidative stress. Moreover, NOX2 inhibition and polyphenol extracts treatment positively modulates redox status and reduce exercise-induced muscular injury.  相似文献   
44.
ObjectiveThis study aims to evaluate the diagnostic accuracy of a new CT sign in order to define or exclude a malignant aetiology of bowel obstruction.Materials and methodsCT scans of 137 patients affected by bowel obstruction were reviewed. Colonic obstruction occurred in 47 (34%) cases, small bowel obstruction in 90 (66%). Neoplastic aetiology was found in 42 cases (31%), while in the remaining 95 (69%) obstruction was caused by non-neoplastic conditions. Definitive diagnosis was surgically confirmed in all patients. CT images were evaluated searching for bowel obstruction's signs and for the presence of the “protruding lips” sign on the proximal surface of stenosis, which is represented by the evidence of a protrusion within the dilated loop.ResultsThe sign was found in 31 (23%) cases, all of neoplastic origin. When malignant obstruction was diagnosed, sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy values of the described sign were 74%, 100%, 100%, 90% and 92%, respectively.ConclusionsThe “protruding lips” sign represents an alteration to be searched when bowel obstruction is diagnosed by CT examination. Its evidence correlates to a malignant condition with a 100% probability and when it is not found, the probability of a non-neoplastic condition is 90%.  相似文献   
45.
46.
The diazotrophic bacteria collectively known as “rhizobia” are important for establishing symbiotic N2-fixing associations with many legumes. These microbes have been used for over a century as an environmentally beneficial and cost-effective means of ensuring acceptable yields of agricultural legumes. The most widely used phylogenetic marker for identification and classification of rhizobia has been the 16S rRNA gene; however, this marker fails to discriminate some closely related species. In this study, we established the first multilocus sequence analysis (MLSA) scheme for the identification and classification of rhizobial microsymbionts of common bean (Phaseolus vulgaris L.). We analyzed 12 Brazilian strains representative of a collection of over 850 isolates in addition to type and reference rhizobial strains, by sequencing recA, dnaK, gltA, glnII and rpoA genes. Gene sequence similarities among the five type/reference Rhizobium strains which are symbionts of common bean ranged from 95 to 100% for 16S rRNA, and from 83 to 99% for the other five genes. Rhizobial species described as symbionts of common bean also formed separate groups upon analysis of single and concatenated gene sequences, and clusters formed in each tree were in good mutual agreement. The five additional loci may thus be considered useful markers of the genus Rhizobium; in addition, MLSA also revealed broad genetic diversity among strains classified as Rhizobium tropici, providing evidence of new species.  相似文献   
47.
Endometriosis is a chronic gynecological disease characterized by the growth of endometrial tissue outside the uterine cavity. Exposure to endocrine disruptors during critical period of development causes long-lasting effects, being the genital system one of the targets. This study describes the effects on female genital system caused by developmental exposure to the endocrine-disrupting chemical bisphenol A (BPA) during pre- and peri-natal development in mice. To this end, timed pregnant Balb-C mice were treated from day 1 of gestation to 7 days after delivery with BPA (100, or 1000 μg/kg/day). After delivery, pups were held for 3 months; then, pelvic organs were analyzed in their entirety and livers of both pups and moms were studied for the presence of BPA. We found in the adipose tissue surrounding the genital tracts of a consistent number of treated animals, endometriosis-like structure with the presence of both glands and stroma and expressing both estrogen receptor and HOXA-10. Moreover, cystic ovaries, adenomatous hyperplasia with cystic endometrial hyperplasia and atypical hyperplasia were significantly more frequent in treated animals respect to the controls. Finally, BPA was found in the livers of exposed moms and female offspring. In conclusion, we describe for the first time an endometriosis-like phenotype in mice, elicited by pre-natal exposition to BPA. This observation may induce to thoroughly reconsider the pathogenesis and treatment of endometriosis, considering the high incidence of endometriosis and the problems caused by associated infertility.  相似文献   
48.
49.
Aim: Surfactant given during brief intubation followed by immediate extubation on nasal continuous positive airway pressure [Intubation‐Surfactant‐Extubation (InSurE) approach] is used to treat respiratory distress syndrome in newborns. Our aim was to evaluate whether bilevel positive airway pressure (BiPAP) after InSurE failure is able to prevent the need for mechanical ventilation (MV). Methods: Chart data of infants with a birth weight <1500 gr or GA <32 weeks undergoing InSurE in the period 2002–2008 in an Italian Tertiary Neonatal Intensive Care Unit were reviewed retrospectively. InSurE failure was defined as follows: FiO2 >0.4, respiratory acidosis or intractable apnoea within 1 week. After InSurE failure, newborns born before the implementation of BiPAP (historical control group) received MV, whereas those born after BiPAP implementation (BiPAP group) received BiPAP and underwent MV only if failure criteria persisted. The two groups were compared to evaluate whether BiPAP reduced the need for MV in the 7 days after InSurE failure. Results: Six of twenty‐two (27%) and 14 of the 38 (37%) infants failed InSurE in the two groups, respectively (p > 0.05). Need for MV was 27% in the historical control group versus 0% in the BiPAP group (risk estimate, 3.38; 95% CI, 2.24, 5.09; p = 0.001). Conclusions: BiPAP reduced the need for MV after InSurE failure.  相似文献   
50.
During kidney allograft rejection, CXC chemokine ligand 10 (CXCL10)–CXC chemokine receptor 3 (CXCR3) trafficking between peripheral blood and tissues initiates alloresponse and perpetuates a self‐inflammatory loop; thus, CXCL10–CXCR3 axis could represent a pharmacologic target. In this perspective, immunosuppressors targeting graft‐resident cells, beside immune cells, could be very advantageous. Vitamin D receptor (VDR) agonists exhibit considerable immunomodulatory properties. This study aimed to investigate whether elocalcitol and BXL‐01‐0029 could decrease the expression of CXCL10 in activated renal tubular cells in vitro and thus be useful in kidney allograft rejection treatment. Experiments were performed in human tubular renal cells stimulated with interferon‐γ + tumor necrosis factor‐α with and without VDR agonists, tacrolimus, sirolimus, hydrocortisone, methylprednisolone, cyclosporin A and mycophenolate mofetil. CXCL10 protein secretion and gene expression were measured by ELISA and by quantitative PCR. Specific inhibitors were used to investigate intracellular pathways involved in tubular cells activation. For IC50 determination and comparison, dose‐response curves with VDR agonists, tacrolimus and mycophenolic acid were performed. Elocalcitol and BXL‐01‐0029 inhibited CXCL10 secretion by renal cells, without affecting cell viability, while almost all the immunosuppressors were found to be ineffective, except for tacrolimus and mycophenolate mofetil. BXL‐01‐0029 was the most potent drug and, notably, it was found to be capable of allowing reduction in tacrolimus‐inhibitory doses. Our data suggest that BXL‐01‐0029 could potentially be a dose‐reducing agent for conventional immunosuppressors in kidney rejection management.  相似文献   
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