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An age-related decline in the functional capacity of the liver has been repeatedly demonstrated by means of dynamic tests. We measured the urea-N synthesis rate in response to a protein-rich meal in 24 healthy subjects divided into three age-groups (less than or equal to 55 years, 56-70 years; greater than or equal to 71 years). No differences were observed in the basal state. The peak urea synthesis and the mean urea synthesis in the 5 hours after the meal were blunted with increasing age, and a negative correlation was present between mean or peak urea synthesis and age (r = -0.572 and r = -0.541, respectively). No differences in basal and post-meal total alpha-amino-nitrogen or individual plasma amino acids were observed. Hormone responses were similar. Galactose elimination capacity was also reduced with increasing age, and correlated with mean and peak urea synthesis after a protein mean (r = 0.640 and r = 0.591, respectively). These data suggest that the capacity of the liver to produce urea in response to a protein-rich meal is reduced in the elderly in relation to a decreased functional liver cell mass. [ABSTRACT FROM AUTHOR]

Purpose: The study aimed to obtain a comprehensive 3D visualization of knee specimens, including the cruciate ligaments and corresponding femoral and tibial bone insertions using a non-destructive micro-CT method., Methods: Knee specimens were fixed in anatomical positions and chemically dehydrated before being scanned using micro-CT with a voxel size of 17.5 μm. RGBA (red, green, blue, alpha) transfer functions were applied to virtually colorize each structure. Following micro-CT scanning, the samples were rehydrated, decalcified, and trimmed based on micro-CT 3D reconstructions as references. Histological evaluations were performed on the trimmed samples. Histological and micro-CT images were registered to morphologically and densitometrically assess the 4-layer insertion of the ACL into the bone., Results: The output of the micro-CT images of the knee in extension and flexion allowed a clear differentiation of the morphologies of both soft and hard tissues, such as the ACL, femoral and tibial bones, and cartilage, and the subsequent creation of 3D composite models useful for accurately tracing the entire morphology of the ligament, including its fiber and bundle components, the trajectory between the femur and tibia, and the size, extension, and morphology of its insertions into the bones., Conclusion: The implementation of the non-destructive micro-CT method allowed complete visualization of all the different components of the knee specimens. This allowed correlative imaging by micro-CT and histology, accurate planning of histological sections, and virtual anatomical and microstructural analysis. The micro-CT approach provided an unprecedented 3D level of detail, offering a viable means to study ACL anatomy., (© 2024. The Author(s).)

Orthorhombic κ-Ga 2 O 3 thin films were grown for the first time on polycrystalline diamond free-standing substrates by metal-organic vapor phase epitaxy at a temperature of 650 °C. Structural, morphological, electrical, and photoelectronic properties of the obtained heterostructures were evaluated by optical microscopy, X-ray diffraction, current-voltage measurements, and spectral photoconductivity, respectively. Results show that a very slow cooling, performed at low pressure (100 mbar) under a controlled He flow soon after the growth process, is mandatory to improve the quality of the κ-Ga 2 O 3 epitaxial thin film, ensuring a good adhesion to the diamond substrate, an optimal morphology, and a lower density of electrically active defects. This paves the way for the future development of novel hybrid architectures for UV and ionizing radiation detection, exploiting the unique features of gallium oxide and diamond as wide-bandgap semiconductors.

Nitroaromatic explosives are the most common explosives, and their detection is important to public security, human health, and environmental protection. In particular, the detection of solid explosives through directly revealing the presence of their vapors in air would be desirable for compact and portable devices. In this study, amino-functionalized carbon nanotubes were used to produce resistive sensors to detect nitroaromatic explosives by interaction with their vapors. Devices formed by carbon nanotube networks working at room temperature revealed trinitrotoluene, one of the most common nitroaromatic explosives, and di-nitrotoluene-saturated vapors, with reaction and recovery times of a few and tens of seconds, respectively. This type of resistive device is particularly simple and may be easily combined with low-power electronics for preparing portable devices.

Objective: To estimate the predictive role of faecal haemoglobin (f-Hb) concentration among subjects with faecal immunochemical test (FIT) results below the positivity cut-off for the subsequent risk of advanced neoplasia (AN: colorectal cancer-CRC-or advanced adenoma)., Design: Prospective cohort of subjects aged 50-69 years, undergoing their first FIT between 1 January 2004 and 31 December 2010 in four population-based programmes in Italy., Methods: All programmes adopted the same analytical procedure (OC Sensor, Eiken Japan), performed every 2 years, on a single sample, with the same positivity cut-off (20 µg Hb/g faeces). We assessed the AN risk at subsequent exams, the cumulative AN detection rate (DR) over the 4-year period following the second FIT and the interval CRC (IC) risk following two negative FITs by cumulative amount of f-Hb concentration over two consecutive negative FITs, using multivariable logistic regression models and the Kaplan-Meier method., Results: The cumulative probability of a positive FIT result over the subsequent two rounds ranged between 7.8% (95% CI 7.5 to 8.2) for subjects with undetectable f-Hb at the initial two tests (50% of the screenees) and 48.4% (95% CI 44.0 to 53.0) among those (0.7% of the screenees) with a cumulative f-Hb concentration ≥20 µg/g faeces. The corresponding figures for cumulative DR were: 1.4% (95% CI 1.3 to 1.6) and 25.5% (95% CI 21.4 to 30.2) for AN; 0.17% (95% CI 0.12 to 0.23) and 4.5% (95% CI 2.8 to 7.1) for CRC. IC risk was also associated with cumulative f-Hb levels., Conclusion: The association of cumulative f-Hb concentration with subsequent AN and IC risk may allow to design tailored strategies to optimise the utilisation of endoscopy resources: subjects with cumulative f-Hb concentration ≥20 µg/g faeces over two negative tests could be referred immediately for total colonoscopy (TC), while screening interval might be extended for those with undetectable f-Hb., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2020. No commercial re-use. See rights and permissions. Published by BMJ.)

Despite alternatives to autogenous bone graft for spinal fusion have been investigated, it has been shown that osteoconductive materials alone do not give a rate of fusion comparable with autogenous bone. This study analyzed a strontium substituted ß-tricalcium phosphate (Sr-ßTCP) associated with syngeneic, unexpanded, and undifferentiated mesenchymal stem cells from bone marrow (BMSC) or adipose tissue (ADSC) as a new tissue engineering approach for spinal fusion procedures. A posterolateral fusion was performed in 15 ovariectomized (OVX) and 15 sham-operated (SHAM) Inbred rats. Both SHAM and OVX animals were divided into three groups: Sr-ßTCP, Sr-ßTCP + BMCSs, and Sr-ßTCP + ADSCs. Animals were euthanized 8 weeks after surgery and the spines evaluated by manual palpation, micro-CT, and histology. For both SHAM and OVX animals, the fusion tissue in the Sr-ßTCP + BMSCs group was more solid. This effect was significantly higher in OVX animals by comparing the Sr-ßTCP + BMCSs group with Sr-ßTCP + ADSCs. Radiographical score, based on micro-CT 2D image, highlighted that the Sr-ßTCP + BMCSs group presented a similar fusion to Sr-ßTCP and higher than Sr-ßTCP + ADSCs in both SHAM and OVX animals. Micro-CT 3D parameters did not show significant differences among groups. Histological score showed significantly higher fusion in Sr-ßTCP + BMSCs group than Sr-ßTCP and Sr-ßTCP + ADSCs, for both SHAM and OVX animals. In conclusion, our results suggest that addition of BMSCs to a Sr-ßTCP improve bone formation and fusion, both in osteoporotic and nonosteoporotic animal, whereas spinal fusion is not enhanced in rats treated with Sr-ßTCP + ADSCs. Thus, for conducting cells therapy in spinal surgery BMSCs still seems to be a better choice compared with ADSCs., (© 2019 Wiley Periodicals, Inc.)

The increasing demand for reliable preclinical models and to reduce, refine and, if possible, replace animal studies have brought forth the development of complex tissue cultures in different research areas, including the musculoskeletal field. In this paper, we review the literature within last 10 years on the state of progress for in vitro models of osteochondral tissue cultures, taking into account the clinical relevance of the management and treatment of osteochondral lesions. According to the selected research criteria, 35 works, 27 of which with animal tissues and 8 with human tissues, resulted to be relevant for the purposes of this review. Data analyzed revealed a great heterogeneity among the proposed tissue culture models. The anatomical harvesting sites resulted to be mainly the knee stifle joint, both for animal (prevalently bovines) and human tissues derived from joint replacement surgery, and significant heterogeneity among culture conditions and media were found. To date, very few papers have focused on the set up of a reproducible in vitro model, applicable to a variety of studies, thus suggesting a relevant gap to fill in the development of advanced three-dimensional osteochondral culture models., (© 2018 Wiley Periodicals, Inc.)

Purpose: To evaluate the regenerative potential of surnatants (SNs) from bone marrow concentrate (SN-BMC) and expanded mesenchymal stromal cells (SN-MSCs) loaded onto a collagen scaffold (SC) in comparison with cell-based treatments (BMC and MSCs) in an osteochondral (OC) defect model in rabbits., Methods: OC defects (3 × 5 mm) were created in the rabbit femoral condyles and treated with SC alone or combined with SN-BMC, SN-MSCs, BMC, and MSCs. In control groups, the defects were left untreated. At three and six months, the quality of regenerated tissue was evaluated with macroscopic, histologic, microtomographic, and immunohistochemical assessments. The production of several immunoenzymatic markers was measured in the synovial fluid., Results: All proposed treatments improved OC regeneration in comparison with untreated and SC-treated defects. Both BMC and MSCs showed a similar healing potential than their respective SNs, with the best performance exerted by BMC as demonstrated with macroscopic and histological scores and type I and II collagen results., Conclusions: SNs loaded onto SC exerted a positive effect on OC defect regeneration, underlying the biological significance of the trophic factors, thus potentially opening new opportunities for the use of cell-free-based therapies. BMC was confirmed to be the most beneficial treatment.

The functional and histological liver alterations induced by amiodarone treatment have been well known for some time and often consist in isolated increases in transaminase levels during long-term treatment. Secondary phospholipidosis was observed in these cases, an alteration which suggests the presence of toxic damage. Reports in the literature also indicate acute liver intoxication, including a number of fatal cases. This paper reports the finding of acute alterations of laboratory parameters indicative of hepatocytonecrosis with alterations of protein synthesis capacity following the first dose of the drug and which regressed after its suspension. On the basis of a review of the literature the authors propose that, in addition to a dose-dependent toxic mechanism, immunogenic or idiosyncratic mechanisms may also play a role in the onset and manifestation of acute liver intoxication by amiodarone.

A poor nutritional status has repeatedly been described in advanced liver cirrhosis, but the exact prevalence of the defect and its relation to the aetiology and severity of liver disease in the Italian population are only partly known. Anthropometric measurements were carried out in 200 patients with cirrhosis (135 M, 65 F). Liver disease was related to alcohol abuse in 77 cases, but most patients had stopped alcohol for at least 6 months before study. In comparison to a normal elderly Italian and to an age-matched North-American population, 5 to 45% of male patients with cirrhosis and 10 to 30% of females had signs of malnutrition, the proportion being variable according to the test used. Male patients showed a remarkable reduction in muscle mass (30-45% of patients, mainly in the presence of moderate-to-severe or severe liver failure), whereas female patients showed a more remarkable reduction of fat stores (15-30% of cases), with advancing liver failure, and a less severe reduction in muscle mass. No direct effect of alcohol was demonstrated in this selected population.

The Authors describe the results of a research conducted in order to evaluate the amount of D-glucaric acid in the urine of 131 operating theatre workers exposed to anesthetic gases and in a control group of 25 non-exposed hospital personnel. The comparison of the results of the two groups points out a significant difference (in the exposed members 60.7 +/- 2.4 mumol/1 to 46.7 +/- 4.3 mumol/l [+/- s.e.] in the control group; t-test: p = 0.016). The research also considered the influence of certain variables such as age, sex, smoking, alcohol, drug use and liver disorders. None of these variables has proven to be of significant influence on the D-glucaric acid urinary concentration.