Multiscale Femoral Neck Imaging and Multimodal Trabeculae Quality Characterization in an Osteoporotic Bone Sample

Although multiple structural, mechanical, and molecular factors are definitely involved in osteoporosis, the assessment of subregional bone mineral density remains the most commonly used diagnostic index. In this study, we characterized bone quality in the femoral neck of one osteoporotic patients as compared to an age-matched control subject, and so used a multiscale and multimodal approach including X-ray computed microtomography at different spatial resolutions (pixel size: 51.0, 4.95 and 0.9 µm), microindentation and Fourier transform infrared spectroscopy. Our results showed abnormalities in the osteocytes lacunae volume (358.08 ± 165.00 for the osteoporotic sample vs. 287.10 ± 160.00 for the control), whereas a statistical difference was found neither for shape nor for density. The osteoporotic femoral head and great trochanter reported reduced elastic modulus (Es) and hardness (H) compared to the control reference (−48% (p < 0.0001) and −34% (p < 0.0001), respectively for Es and H in the femoral head and −29% (p < 0.01) and −22% (p < 0.05), respectively for Es and H in the great trochanter), whereas the corresponding values in the femoral neck were in the same range. The spectral analysis could distinguish neither subregional differences in the osteoporotic sample nor between the osteoporotic and healthy samples. Although, infrared spectroscopic measurements were comparable among subregions, and so regardless of the bone osteoporotic status, the trabecular mechanical properties were comparable only in the femoral neck. These results illustrate that bone remodeling in osteoporosis is a non-uniform process with different rates in different bone anatomical regions, hence showing the interest of a clear analysis of the bone microarchitecture in the case of patients’ osteoporotic evaluation.     

Geotechnical and Shear Behavior of Novel Lunar Regolith Simulants TUBS-M,TUBS-T,and TUBS-I

The return to the Moon is an important short-term goal of NASA and other international space agencies. To minimize mission risks, technologies, such as rovers or regolith processing systems, must be developed and tested on Earth using lunar regolith simulants that closely resemble the properties of real lunar soil. So far, no singular lunar simulant can cover the multitude of use cases that lunar regolith involves, and most available materials are poorly characterized. To overcome this major gap, a unique modular system for flexible adaptable novel lunar regolith simulants was developed and chemically characterized in earlier works. To supplement this, the present study provides comprehensive investigations regarding geotechnical properties of the three base regolith simulant systems: TUBS-M, TUBS-T, and TUBS-I. To evaluate the engineering and flow properties of these heterogeneous materials under various conditions, shear tests, particle size analyses, scanning electron microscope observations, and density investigations were conducted. It was shown that small grains <25 µm (lunar dust) are highly compressive and cohesive even at low external stress. They are particularly important as a large amount of fine dust is present in lunar regolith and simulants (x₅₀ = 76.7 to 96.0 µm). Further, ring shear and densification tests revealed correlations with damage mechanisms caused by local stress peaks for grains in the mm range. In addition, an explanation for the occurrence of considerable differences in the literature-based data for particle sizes was established by comparing various measurement procedures. The present study shows detailed geotechnical investigations of novel lunar regolith simulants, which can be used for the development of equipment for future lunar exploration missions and in situ resource utilization under realistic conditions. The results also provide evidence about possible correlations and causes of known soil-induced mission risks that so far have mostly been described phenomenologically.     

Home Artificial Nutrition and Energy Balance in Cancer Patients: Nutritional and Clinical Outcomes

Malnutrition is one of the main factors determining cachexia syndrome, which negatively impacts the quality of life and survival. In cancer patients, artificial nutrition is considered as an appropriate therapy when the impossibility of an adequate oral intake worsened nutritional and clinical conditions. This study aims to verify, in a home palliative care setting for cancer patients, if home artificial nutrition (HAN) supplies a patient’s energy requirement, improving nutritional and performance status. A nutritional service team performed counseling at a patient’s home and assessed nutritional status (body mass index, weight loss in the past 6 months), resting energy expenditure (REE), and oral food intake; Karnofsky Performance Status (KPS); cachexia degree; and survival. From 1990 to 2021, 1063 patients started HAN. Among these patients, 101 suspended artificial nutrition for oral refeeding. Among the 962 patients continuing HAN until death, 226 patients (23.5%) survived 6 weeks or less. HAN allowed to achieve a positive energy balance in 736 patients who survived more than 6 weeks, improving body weight and KPS when evaluated after 1 month of HAN. Advanced cancer and cachexia degree at the entry of the study negatively affected the positive impact of HAN.     

Accuracy of planned tooth movement with lingual straight wire technique

ObjectivesTo analyze the accuracy of planned tooth movements of torque, tip, rotations, and transverse width values with lingual straight-wire technique.Materials and Methods40 Caucasian subjects with mean age of 23.9 years, consecutively treated in private practice with a lingual straight-wire appliance (STb, Ormco, Glendora, Calif) were evaluated. Maxillary and mandibular dental casts were taken before treatment (T0), in the setup (T1), and at the end of treatment (T2) and scanned with an intraoral 3D scanner Carestream CS 3600 (Carestream Dental, Atlanta, GA). Virtual models at the three time points were superimposed on T1 using 3D software, and the coordinates were exported as a set of x, y, and z values. Angular and linear measurements were analyzed to measure torque, tip, rotation movements, and transverse intra-arch widths. Changes among the three time points were analyzed with Friedman''s nonparametric test.ResultsA general increase in torque was recorded in the setup and in the final result, except for the maxillary molars. Torque, tip, and rotation movement mean accuracy was ≥84% for incisors, canines, and premolars. A general increase in transverse width was measured in the setup and in the final models, except for the upper second molars, which showed reduced transverse width during treatment.ConclusionsThe movements planned in the setup to obtain the ideal torque, tip, and rotations actually occurred, except for second molars, which showed less accuracy. Planned expansion of the arches occurred only partially.     

Prospective, Randomized, Multi-Center Trial of Antibody Induction Therapy in Simultaneous Pancreas-Kidney Transplantation

A randomized, multicenter, prospective study was conducted at 18 pancreas transplant centers in the United States to determine the role of induction therapy in simultaneous pancreas-kidney (SPK) transplantation. One hundred and 74 recipients were enrolled: 87 recipients each in the induction and noninduction treatment arms. Maintenance immunosuppression consisted of tacrolimus, mycophenolate mofetil, and corticosteroids. There were no statistically significant differences between treatment groups for patient, kidney, and pancreas graft survival at 1-year. The 1-year cumulative incidence of any treated biopsy-confirmed or presumptive rejection episodes (kidney or pancreas) in the induction and noninduction treatment arms was 24.6% and 31.2% (p = 0.28), respectively. The 1-year cumulative incidence of biopsy-confirmed, treated, acute kidney allograft rejection in the induction and noninduction treatment arms was 13.1% and 23.0% (p = 0.08), respectively. Biopsy-confirmed kidney allograft rejection occurred later post-transplant and appeared to be less severe among recipients that received induction therapy. The highest rate of Cytomegalovirus (CMV) viremia/syndrome was observed in the subgroup of recipients who received T-cell depleting antibody induction and received organs from CMV serologically positive donors. Decisions regarding the routine use of induction therapy in SPK transplantation must take into consideration its differential effects on risk of rejection and infection.     

Mast cells and tumour angiogenesis: new insight from experimental carcinogenesis

Histopathologic examination and clinical observations of solid and haematological malignancies indicates mast cells as key host cells in the tumour infiltrate, with important consequence on tumour-associated angiogenesis and tumour growth. Data suggest indeed that tumour-infiltrating mast cells may exert a prominent function in the angiogenic "switch", which is essential for the progression of early tumours. The experimental approach has substantially increased our understanding of the role of tumour-infiltrating mast cells in the process of angiogenesis that accompanies tumour development. This review will focus on the crucial contribution of mast cells in promoting tumour neovascularization as it emerges from the most recent observations of experimental carcinogenesis in in vivo and in vitro models.     

Risk of retinal vein occlusion following COVID-19 vaccination: a self-controlled case series

BackgroundTo evaluate the association between COVID-19 vaccination and retinal vein occlusion (RVO).MethodsThis multicentre self-controlled case series included patients with RVO seen in five tertiary referral centres in Italy. All adults who received at least one dose of the BNT162b2, ChAdOx1 nCoV-19, mRNA-1273 or Ad26.COV2.S vaccine and had a first diagnosis of RVO between January 01, 2021, and December 31, 2021 were included. Incidence rate ratios (IRRs) of RVO were estimated using Poisson regression, comparing rates of events in a 28-day period following each dose of vaccination and in the unexposed control periods.Results210 patients were included in the study. No increased risk of RVO was observed after the first dose (1–14 days IRR: 0.87, 95% CI: 0.41–1.85; 15–28 days IRR: 1.01, 95% CI: 0.50–2.04; 1–28 days IRR: 0.94, 95% CI: 0.55–1.58) and second dose of vaccination (1–14 days IRR: 1.21, 95% CI: 0.62–2.37; 15–28 days IRR: 1.08, 95% CI: 0.53–2.20; 1–28 days IRR: 1.16, 95% CI: 0.70–1.90). No association between RVO and vaccination was found in subgroup analyses by type of vaccine, gender and age.ConclusionsThis self-controlled case series found no evidence of an association between RVO and COVID-19 vaccination.Subject terms: Retinal diseases, Epidemiology