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991.
992.
Diego Gaddi Simone D. Gatti Massimiliano Piatti Andrea Poli Laura De Rosa Andrea Riganti Giovanni Zatti Marco Bigoni Marco Turati 《Indian Journal of Orthopaedics》2023,57(1):137
IntroductionBone consolidation defects represent a real orthopedic challenge because of the absence of validated treatment guidelines that can assist the surgeon in his choices. The aim of this study is to evaluate the appropriateness of the Non-Union Scoring System NUSS treatment protocol in the management of long bone non-unions by comparing it to the experience-based therapeutic approach carried out in our facility.Materials and MethodsWe conducted a comparative outcome study of a retrospective series of 89 patients surgically treated for long bone non-union in our facility vs. clinical results reported by Calori et al. obtained following the NUSS treatment protocol.ResultsRadiographic healing was reached in 13/13 non-unions (100%) in group NUSS 1, in 58/62 (93.5%) in group NUSS 2, and in 13/14 (92.9%) in group NUSS 3. The mean time to radiographic healing was 5.69 ± 2.09 months in group 1, 7.38 ± 3.81 months in group 2 and 9.23 ± 2.31 months in group 3. 91% of patients in group I, 69% in group II and 48% in group III received what would be considered by the NUSS treatment protocol an “overtreatment”, especially from a biological stand point. The comparative outcome analysis shows that our case series achieved significantly higher global healing rates (p value = 0.017) and shorter radiological healing times in groups NUSS 1 and 2 (p value < 0.001).ConclusionFrom the results obtained, we can assume that the NUSS treatment protocol might underestimate the necessary therapies, particularly from a biological point of view. 相似文献
993.
Silvia Greco Stefania Manzi Luisa Molari Andrea Saccani Gianfranco Ulian Giovanni Valdr 《Materials》2023,16(1)
One of the main concerns in using natural materials in construction, such as bamboo, regards their durability. Ultra violet (UV)irradiation is claimed as a damaging agent; therefore, it is important to study its effect. Several studies have shown that bamboo components such as lignin are subjected to photochemical degradation, but it is not well understood how this affects the mechanical properties of bamboo. The aim of this paper is to explore the correlation between photodegradation and bamboo mechanical performance. Bamboo samples were exposed to accelerated UV ageing for different times (from 6 to 360 h) and then subjected to a four-point bending test. Since one of the ways to stabilize bamboo is to thermally treat it, the tests were conducted on natural untreated bamboo and treated bamboo with a traditional flame treatment. Modifications of the chemical features of the material were analyzed with Fourier Trasform Infra Red (FTIR) spectroscopy, while modifications of the morphological features were analyzed byEnvironmental Scanning Electron Microscopy ESEM and optical microscopy observations. The results show that the bending behavior of bamboo is not compromised by UV exposure up to 360 h. In fact, although a progressive degradation of lignin is reported and cracks in the fiber walls are highlighted from micrographs, no effects were found on the fiber length. 相似文献
994.
Massimo Fabiani Alberto Mateo-Urdiales Chiara Sacco Emmanouil Alexandros Fotakis Maria Cristina Rota Daniele Petrone Marco Bressi Martina Del Manso Andrea Siddu Giorgio Fedele Paola Stefanelli Antonino Bella Flavia Riccardo Anna Teresa Palamara Giovanni Rezza Silvio Brusaferro Patrizio Pezzotti 《Euro surveillance : bulletin européen sur les maladies transmissibles = European communicable disease bulletin》2023,28(8)
Effectiveness against severe COVID-19 of a second booster dose of the bivalent (original/BA.4–5) mRNA vaccine 7–90 days post-administration, relative to a first booster dose of an mRNA vaccine received ≥ 120 days earlier, was ca 60% both in persons ≥ 60 years never infected and in those infected > 6 months before. Relative effectiveness in those infected 4–6 months earlier indicated no significant additional protection (10%; 95% CI: −44 to 44). A second booster vaccination 6 months after the latest infection may be warranted. 相似文献
995.
Paola Gallo Stampino Laura Riva Marco Caruso Imran Abdul Rahman Graziano Elegir Daniele Bussini Javier Marti-Rujas Giovanni Dotelli Carlo Punta 《Materials》2023,16(1)
Interest towards cellulose nanofibers obtained from virgin and waste sources has seen a significant growth, mainly thanks to the increasing sensitivity towards the concept of circular economy and the high levels of paper recycling achieved in recent years. Inspired by the guidelines of the green building industry, this study proposes the production and characterization of TEMPO-oxidized and homogenized cellulose nanofibers (TOHO CNF) from different sources and their use as additives for earth plasters on two different raw earth samples, characterized by geotechnical laboratory tests and mineralogical analysis: a high-plasticity clay (T2) and a medium-compressibility silt (ABS). Original sources, including those derived from waste (recycled cardboard and paper mill sludge), were characterized by determining chemical content (cellulose versus ashes and lignin) and fiber morphology. TOHO CNF derived from the different sources were compared in terms of nanofibers medium diameter, crystallinity degree, thermal decomposition and oxidation degree, that is the content of carboxylic groups per gram of sample. Then, a preliminary analysis of the influence of CNF on earth plasters is examined. Adhesion and capillary absorption tests highlighted the effect of such nanofibers on blends in function of two factors, namely the cellulose original source and the oxidation degree of the fibers. In particular, for both earth samples, T2 and ABS, a significant increase in adhesion strength was observed in the presence of some TOHO CNF additives. As far as capillary sorption tests, while an undesired increase in water adsorption was detected for T2 compared to the control, in the case of ABS, a significant reduction in water content was measured by adding TOHO CNF derived from recycled sources. These results pave the way for further in-depth investigation on the role of TOHO CNF as additives for earth plasters. 相似文献
996.
997.
Giovanni Corsetti Claudia Romano Silvia Codenotti Evasio Pasini Alessandro Fanzani Francesco S. Dioguardi 《Nutrients》2022,14(14)
Background: Excess body adipose tissue accumulation is a common and growing health problem caused by an unbalanced diet and/or junk food. Although the effects of dietary fat and glucose on lipid metabolism regulation are well known, those of essential amino acids (EAAs) have been poorly investigated. Our aim was to study the influence of a special diet containing all EAAs on retroperitoneal white adipose tissue (rpWAT) and interscapular brown adipose tissue (BAT) of mice. Methods: Two groups of male Balb/C mice were used. The first was fed with a standard diet. The second was fed with an EAAs-rich diet (EAARD). After 3 weeks, rpWAT and BAT were removed and prepared for subsequent immunohistochemical analysis. Results: EAARD, although consumed significantly less, moderately reduced body weight and BAT, but caused a massive reduction in rpWAT. Conversely, the triceps muscle increased in mass. In rpWAT, the size of adipocytes was very small, with increases in leptin, adiponectin and IL-6 immunostaining. In BAT, there was a reduction in lipid droplet size and a simultaneous increase in UCP-1 and SIRT-3. Conclusions: A diet containing a balanced mixture of free EAA may modulate body adiposity in mice, promoting increased thermogenesis. 相似文献
998.
Jeremy D. Gale 《Advances in therapy》2009,26(5):519-530
Chronic idiopathic constipation (CIC) and irritable bowel syndrome with constipation (C-IBS) are commonly reported gastrointestinal
(GI) disorders that have a major impact on health and quality of life. Patients experience a range of symptoms of which infrequency
of bowel movement is but one and report that straining, the production of hard stools, and unproductive urges are more bothersome
than stool infrequency. Additionally, in C-IBS, patients report abdominal pain and bloating as particularly troubling. Traditional
treatments, such as laxatives, are often ineffective, especially in more severe constipation over the long term. In a population-based
survey of constipation sufferers, half were not satisfied with their current treatment, due predominantly to poor efficacy.
5-Hydroxytryptamine receptor 4 (5-HT4) agonists stimulate GI motility and intestinal secretion, and tegaserod has demonstrated efficacy in improving bowel habit.
Tegaserod also improves constipationassociated symptoms including bloating, abdominal discomfort, stool consistency, and straining
in patients with both CIC and C-IBS. However, tegaserod has been withdrawn due to an association with serious adverse cardiovascular
effects. Further 5-HT4 receptor agonists, including prucalopride and TD-5108 are in development and show exciting results in clinical studies in
CIC patients, suggesting further product approvals are likely. Headache and diarrhea are the most commonly reported adverse
event with this class of agent. Recently a novel prosecretory agent has been approved for the treatment of both CIC and C-IBS.
Lubiprostone stimulates chloride secretion through activation of type-2 chloride channels, increasing intestinal secretion
and transit, and its use has been associated with improvements in bowel habit and symptoms of constipation. Nausea, diarrhea,
and headache are the most commonly reported adverse events. Linaclotide also stimulates intestinal chloride secretion, but
this molecule achieves this indirectly, through the activation of guanylate cyclase C. Data are emerging, but the efficacy
and safety profile of this agent in the treatment of CIC and C-IBS appears encouraging. 相似文献
999.
Zhong-Wei Chen Huan-Ming Xiao Xinjian Ye Kun Liu Rafael S. Rios Kenneth I. Zheng Yi Jin Giovanni Targher Christopher D. Byrne Junping Shi Zhihan Yan Xiao-Ling Chi Ming-Hua Zheng 《肝胆外科与营养》2022,11(2):212
BackgroundCurrently, there are no effective methods for assessing hepatic inflammation without resorting to histological examination of liver tissue obtained by biopsy. T2-weighted images (T2WI) are routinely obtained from liver magnetic resonance imaging (MRI) scan sequences. We aimed to establish a radiomics signature based on T2WI (T2-RS) for assessment of hepatic inflammation in people with nonalcoholic fatty liver disease (NAFLD).MethodsA total of 203 individuals with biopsy-confirmed NAFLD from two independent Chinese cohorts with liver MRI examination were enrolled in this study. The hepatic inflammatory activity score (IAS) was calculated by the unweighted sum of the histologic scores for lobular inflammation and ballooning. One thousand and thirty-two radiomics features were extracted from the localized region of interest (ROI) in the right liver lobe of T2WI and, subsequently, selected by minimum redundancy maximum relevance and least absolute shrinkage and selection operator (LASSO) methods. The T2-RS was calculated by adding the selected features weighted by their coefficients.ResultsEighteen radiomics features from Laplacian of Gaussian, wavelet, and original images were selected for establishing T2-RS. The T2-RS value differed significantly between groups with increasing grades of hepatic inflammation (P<0.01). The T2-RS yielded an area under the receiver operating characteristic (ROC) curve (AUROC) of 0.80 [95% confidence interval (CI): 0.71–0.89] for predicting hepatic inflammation in the training cohort with excellent calibration. The AUROCs of T2-RS in the internal cohort and external validation cohorts were 0.77 (0.61–0.93) and 0.75 (0.63–0.84), respectively.ConclusionsThe T2-RS derived from radiomics analysis of T2WI shows promising utility for predicting hepatic inflammation in individuals with NAFLD. 相似文献
1000.
INTRODUCTION: The aim of our study was to analyse the role of adrenomedullin (AM) and endothelin-1 (ET-1) in the adaptation of the maternal vascular system in normotensive pregnancy. METHODS: Twenty-eight pregnant women, who were normotensive throughout the duration of their pregnancy, were recruited into the study. Plasma levels of AM and ET-1 at each trimester were measured and the AM/ET-1 ratio was calculated. RESULTS: Our experiment showed a significant decrease in plasma concentrations of AM in the first trimester for the study group (n=28) compared with the non-pregnant control group (n=16). There was also a significant decrease in plasma concentrations of ET-1 in all three trimesters (P<0.05) and a significant increase in the AM/ET-1 ratio in all three trimesters (P<0.05) for the study group compared with the control group. CONCLUSION: An alteration in vascular equilibrium between AM and ET-1, favouring AM, may be a reason why the physiological adaptation of the maternal vascular system to pregnancy occurs during normotensive pregnancy. 相似文献