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Background and Objectives: Endoscopic endonasal surgery is a well-established surgical approach to the skull base. Surgeons need a reusable long-lasting tool to acquire the skills needed for skull base reconstruction. The aim of this study was to elaborate and validate a human formalin-fixed cadaveric model that reproduces a realistic cerebrospinal fluid (CSF) circulation and that adequately renders a CSF leak., Methods: An external ventricular drain that connects with a peristaltic pump is placed in the subarachnoid space, which allows a water circulation that reproduces CSF circulation. Intracranial pressure is measured in real time. Endoscopic endonasal skull base approaches are performed, to create different skull base openings and CSF leaks. Participants were tasked with reconstruction of the defects using a standardized multilayered approach, with the goal of obtaining a watertight closure under normal intracranial pressure ranges. Compiled data included time of reconstruction, years of experience of participants, and success/failure to achieve a watertight reconstruction. A Likert questionnaire was also used., Results: The cadaveric model reproduced CSF circulation in 4 types of dural defects: sellar, suprasellar, transcribriform, and transclival. Intracranial pressures were similar to physiological conditions and were reproducible. Each model was tested multiple times, over several months. Success rates concurred with training levels (r = .8282 and P = .0017). A strong inverse correlation was also found between years of experience and time of reconstruction (r = .4977 and P < .0001). Participants agreed that the model was realistic (median Likert score of 4), and they strongly agreed that it allowed for the improvement of their surgical skills (median Likert score of 5)., Conclusion: This novel human-fixed cadaveric model for CSF circulation is efficient and adequately reproduces surgical conditions for skull base approaches. The model is unique, easy to reproduce, and reusable. It can be used as a tool for teaching and for research purposes., (Copyright © Congress of Neurological Surgeons 2024. All rights reserved.)

Background: Nitrite salts are frequently utilized as meat additives to improve the quality and safety of processed meat products. However, these salts are associated with the formation of carcinogenic nitrosamines. Given its potential regulating effect on the formation of intermediate molecules, such as nitric oxide, it is hypothesized that carnosine, a meat constituent possessing antioxidant activity and other multiple health benefits, could dampen the formation of nitrosamines. The current study therefore assessed the effect of carnosine on nitrosamine formation in both a monophasic aqueous system and a biphasic water-lipid system simulating a gastric environment., Results: In the monophasic system, relatively high levels of carnosine were required to significantly reduce the formation of different species of nitrosamine compared with the control (no carnosine). While higher levels of some nitrosamines were generated in both phases of the biphasic system, low carnosine concentrations significantly suppressed nitrosamine formation in the aqueous phase, while in the lipid phase, intermediate levels of carnosine were required. At higher carnosine levels, further reduction in nitrosamines was observed in the lipid phase., Conclusions: This study demonstrates the capacity of carnosine to reduce nitrosamine formation in aqueous and lipid environments and suggests the potential of dietary carnosine to lower the risks associated with the consumption of processed meat products. © 2024 His Majesty the King in Right of Canada and The Author(s). Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. Reproduced with the permission of the Minister of Agriculture and Agri-Food Canada., (© 2024 His Majesty the King in Right of Canada and The Author(s). Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. Reproduced with the permission of the Minister of Agriculture and Agri‐Food Canada.)

The beneficial role of carnosine during in vitro digestion of meat was previously demonstrated, and it was hypothesized that such benefits could also be obtained in a meal system. The current study, therefore, assessed carnosine effects on markers of lipid and protein oxidation and of advanced glycation end products (AGEs) during gastric and duodenal in vitro digestion of a burger meal model. The model included intrinsic (low) and enhanced (medium and high) carnosine levels in a mix of pork mince and bread, with or without ascorbic acid (AA) and/or fructose as anti- and prooxidants, respectively. In the presence of either AA or fructose, a carnosine prooxidative potential during digestion was observed at the medium carnosine level depending on markers and digestive phases. However, free carnosine found at the high carnosine level exerted a protective effect reducing the formation of 4-hydroxynonenal in the gastric phase and glyoxal in both the gastric and duodenal phases. Dual effects of carnosine are likely concentration related, whereby at the medium level, free radical production increases through carnosine's ferric-reducing capacity, but there is insufficient quantity to reduce the resulting oxidation, while at the higher carnosine level some decreases in oxidation are observed. In order to obtain carnosine benefits during meal digestion, these findings demonstrate that consideration must be given to the amount and nature of other anti- and prooxidants present and any potential interactions. PRACTICAL APPLICATION: Carnosine, a natural compound in meat, is a multifunctional and beneficial molecule for health. However, both pro- and antioxidative effects of carnosine were observed during digestion of a model burger meal when ascorbic acid was included at a supplemental level. Therefore, to obtain benefits of dietary carnosine during digestion of a meal, consideration needs to be given to the amount and nature of all anti- and prooxidants present and any potential interactions., (© 2023 His Majesty the King in Right of Canada. Journal of Food Science published by Wiley Periodicals LLC on behalf of Institute of Food Technologists. Reproduced with the permission of the Minister of Agriculture and Agri Food Canada.)

It is generally accepted that carnosine (β-alanyl-L-histidine) content is higher in glycolytic than in oxidative muscle fibres, but the underlying mechanisms responsible for this difference remain to be elucidated. A first study to better understand potential mechanisms involved was undertaken (1) to determine whether differences in the expression of carnosine-related enzymes (CARNS1, CNDP2) and transporters (SLC6A6, SLC15A3, SLC15A4, SLC36A1) exist between oxidative and glycolytic myofibres and (2) to study the effect of carnosine on myoblast proliferative growth and on carnosine-related gene expression in cultured myoblasts isolated from glycolytic and oxidative muscles. Immunohistochemistry analyses were conducted to determine the cellular localization of carnosine-related proteins. Laser-capture microdissection and qPCR analyses were performed to measure the expression of carnosine-related genes in different myofibres isolated from the longissimus dorsi muscle of ten crossbred pigs. Myogenic cells originating from glycolytic and oxidative muscles were cultured to assess the effect of carnosine (0, 10, 25 and 50 mM) on their proliferative growth and on carnosine-related gene expression. The mRNA abundance of CNDP2 and of the studied carnosine transporters was higher in oxidative than in glycolytic myofibres. Since carnosine synthase (CARNS1) mRNA abundance was not affected by either the fibre type or the addition of carnosine to myoblasts, its transcriptional regulation would not be the main process by which carnosine content differences are determined in oxidative and glycolytic muscles. The addition of carnosine to myoblasts leading to a dose-dependent increase in SLC15A3 transcripts, however, suggests a role for this transporter in carnosine uptake and/or efflux to maintain cellular homeostasis., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Pituitary composite tumors consisting of metastasis within an adenoma are rare and aggressive entities. We present a case of esophageal adenocarcinoma metastasis at a prolactinoma presenting in a unique fashion and highlight how this case could contribute to a better understanding and early recognition of this condition. The patient was a 65-year-old male who presented with partial palsy of the third and sixth cranial nerves. He had a history of treated esophageal adenocarcinoma. He also had a known small parasellar lesion, with an elevated prolactin. Investigations showed a rapid progression of the parasellar lesion and normalization of prolactin. Partial surgical resection was performed, and pathology confirmed metastasis of the known digestive tract neoplasia. Although extremely rare, dual pathology of pituitary metastasis within adenomas should be considered in the differential diagnosis of sellar masses. Atypical behavior of benign adenomas, including rapid growth, spontaneous normalization of prolactin, or progression despite medical treatment should prompt medical teams to reconsider their diagnosis., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2023, Gariépy et al.)

Background and Purpose: The quality of leptomeningeal collaterals may influence the speed of infarct progression in acute stroke. Our main objective was to evaluate the association of leptomeningeal collateral score and its interaction with time with ischemic changes on CT in patients with acute stroke., Materials and Methods: Adult patients with acute stroke symptoms and anterior circulation large-vessel occlusion on CTA from 2015 to 2019 were included. Routinely performed NCCT and multiphase CTA were reviewed to assess ASPECTS and the leptomeningeal collateral score. We built multivariate regression models to assess the association between leptomeningeal collateral score and its interaction with time and ASPECTS. Performance measures to predict poor ASPECTS at different time thresholds (identified with receiver operating characteristic curve analysis) were estimated in a subgroup of patients with poor leptomeningeal collateral scores., Results: Leptomeningeal collateral scores 0-1 were associated with lower ASPECTS, and the model with dichotomized and trichotomized leptomeningeal collateral score showed a significant multiplicative interaction between time and the leptomeningeal collateral score. The negative predictive value for poor ASPECTS was >0.9 for at least the first 3 hours from stroke onset to imaging, and the positive predictive value was <0.5 for every time threshold tested in the subgroup of patients with leptomeningeal collateral scores 0-3., Conclusions: Poor (0-1) leptomeningeal collateral scores were associated with lower ASPECTS, and an increase in time has a multiplicative interaction with the leptomeningeal collateral score on ASPECTS., (© 2022 by American Journal of Neuroradiology.)

The fibrous structure of meat muscle makes it an anisotropic optical material. As such, spectral information varies with the orientation of the muscle. In this study, spectral data from pork cuts were obtained by a transverse scan (TRANSCAN), radial scan (RADISCAN), and longitudinal scan (LONGSCAN) by using hyperspectral imaging. The information was used to develop and compare the prediction models for intramuscular (IMF) content prediction by partial least square regression (PLSR), support vector machines regression (SVMR), and backpropagation artificial neural network (BPANN). The three modeling algorithms showed equal capability for modeling IMF in pork. The accuracy of the prediction models from the three scans was in the order of TRANSCAN ≥ RADISCAN ≥ LONGSCAN. Successive projection algorithm reduced the wavelengths to 93%. The reduced wavelengths were used to build new models that showed similar accuracy to the models of the original wavelengths. This study shows that muscle orientation influences the accuracy of the prediction models., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Objective: We conducted a systematic review/meta-analysis to evaluate noninvasive brain stimulation (NIBS) efficacy to alleviate pain and improve disability in low back pain (LBP)., Materials and Methods: A systematic literature search was performed by a librarian in MEDLINE, Embase, EBM Reviews, CINAHL, and Web of Science databases (last search: January 14, 2021). Data were pooled by the number of sessions and follow-up periods. Independent reviewers performed screening, data extraction, and risk of bias. Pain reduction and disability were used as outcomes., Results: Twelve articles were included in the qualitative synthesis and 8 in the meta-analysis. A single session of NIBS reduced pain compared with sham (standardized mean difference: -0.47; P<0.001; very low-quality evidence). Repeated sessions of NIBS did not impact pain at short-term (mean difference [MD]: -0.31; P=0.23) or midterm (MD: -0.56; P=0.33; moderate quality evidence). Combining NIBS with cointerventions did not influence pain (MD: -0.31; P=0.30; moderate quality evidence). NIBS did not have a statistically significant impact on disability., Discussion: There is very low-quality evidence suggesting that a single NIBS session reduces LBP intensity. In contrast, there is moderate quality evidence that repeated NIBS sessions or combination with cointervention did not improve pain or disability. Thus, current results do not support NIBS use to treat chronic LBP. Considering that tDCS was tested in 8 of 12 studies with little success, studies focusing on different NIBS techniques or innovative parameters are required to determine their potential to improve pain and disability in chronic LBP., Competing Interests: The authors declare no conflict of interest., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

Muscle carnosine represents an important health advantage of meat. Ground pork samples with intrinsic or added carnosine; fat content; and cooked under low or high intensity as a 2 × 2 × 2 factorial were digested in-vitro. Changes in free carnosine and in markers of lipid (hexanal, 4-hydroxynonenal (4-HNE), malondialdehyde (MDA) and protein (protein-carbonyls, thiols) oxidation, and of advanced glycation end-products (AGEs) N ε -(carboxymethyl)lysine (CML) were determined in the saliva, gastric, and duodenal digests. During digestion, the different markers overall indicated increased oxidation and decreased free carnosine. Increasing pork carnosine level significantly reduced protein carbonyls, loss of thiols, and 4-HNE during in-vitro gastric digestion, irrespective of fat and cooking level of the meat. Increased carnosine also significantly reduced hexanal, MDA and CML up to the duodenum phase in moderately cooked lean pork. Besides substantiating the formation of AGEs during digestion, these results show a potentially important role of dietary carnosine occurring in the gastrointestinal tract. PRACTICAL APPLICATIONS: The ailments epidemiologically associated with red meat consumption could be counteracted by ingesting carnosine into meat. The health advantages of dietary carnosine, however, have never been demonstrated during digestion, a unique and complex oxidative environment compounded by the composition and cooking of the meat. The results obtained substantiated that AGEs formation occurred in-vitro in the GIT. They also showed that increased carnosine had an immediate health beneficial role during pork digestion in reducing the formation of different harmful molecules, including AGEs, modulated by the composition and cooking of the meat. However, in exerting this protective role in the GIT, the remaining free level of carnosine, gradually decreased during digestion. Carnosine, as an important meat compositional factor may, depending on the fat content and cooking conditions, change the image of meat from representing a health risk to a health benefit. Carnosine level may also explain discrepancies observed in the literature., (© 2021 Her Majesty the Queen in Right of Canada. Journal of Food Biochemistry published by Wiley Periodicals LLC. Reproduced with the permission of the Minister of Agriculture and Agri-Food Canada.)

Carnosine is a naturally occurring histidine-containing dipeptide present at high concentration in mammalian skeletal muscles. Carnosine was shown to affect muscle contraction, prevent the accumulation of oxidative metabolism by-products and act as an intracellular proton buffer maintaining the muscle acid-base balance. The present study was undertaken to gain additional knowledge about the intracellular mechanisms activated by carnosine in porcine myoblast cells under basal and oxidative stress conditions. Satellite cells were isolated from the skeletal muscles of 3 to 4 day-old piglets to study the effect of 0, 10, 25 and 50 mM carnosine pre-treatments in cells that were exposed (0.3 mM H2O2) or not to an H2O2-induced oxidative stress. Study results demonstrated that carnosine acts differently in myoblasts under oxidative stress and in basal conditions, the only exception being with the reduction of reactive oxygen species and protein carbonyls observed in both experimental conditions with carnosine pre-treatment. In oxidative stress conditions, carnosine pre-treatment increased the mRNA abundance of the nuclear factor, erythroid 2 like 2 (NEF2L2) transcription factor and several of its downstream genes known to reduce H2O2. Carnosine prevented the H2O2-mediated activation of p38 MAPK in oxidative stress conditions, whereas it triggered the activation of mTOR under basal conditions. Current results support the protective effect of carnosine against oxidative damage in porcine myoblast cells, an effect that would be mediated through the p38 MAPK intracellular signaling pathway. The activation of the mTOR signaling pathway under basal condition also suggest a role for carnosine in myoblasts proliferation, growth and survival., Competing Interests: The authors have declared that no competing interests exist.

Pork bellies (n = 198) were scanned with dual energy X-ray absorptiometry (DXA). Visible and near-infrared reflectance (Vis-NIR) spectra were collected from the lean (latissimus dorsi), subcutaneous fat and intermuscular fat layers. Belly-flop angle and subjective belly scores were collected as measures of pork belly softness. Vis-NIR spectra from a single fat layer could explain between 72.7 and 81.1% of the variation in pork belly softness (43.6-72.4% in validation set). The combination of the lean and subcutaneous layers improved the calibration model fit to 79.7-99.9% (66.3-71.5% in validation set). The DXA estimates explained 62.3% of variation in pork belly softness (65.2% in validation set). Results indicated that DXA and NIR technologies could potentially be utilized for pork belly softness sorting in the pork industry., (Copyright © 2018. Published by Elsevier Ltd.)

A matched case-control study in Quebec, Canada, evaluated consumption of veal liver as a risk factor for campylobacteriosis. Campylobacter was identified in 28 of 97 veal livers collected concurrently from slaughterhouses and retailers. Veal liver was associated with human Campylobacter infection, particularly when consumed undercooked.

Carnosine has pH-buffering and antioxidant properties that may bring advantages in terms of meat quality attributes. This study aimed at identifying polymorphisms in carnosine-related genes (CARNS1, SLC6A6, SLC15A3, SLC15A4) that might associate with muscle carnosine content and meat quality traits in pigs (Duroc, Landrace, Yorkshire). Twenty seven SNPs were identified and association analyses performed for SLC15A3 c.*35C>T and c.*52C>T (3' UTR region), and SLC15A4 c.658A>G (Ile220Val) and c.818G>A (Ser273Asn) SNPs. Associations were observed for SNP c.658A>G with carnosine content, color b* and L*, drip and cooking losses, pH24h and glycolytic potential values (P≤0.05). The same associations were observed for SNP c.818G>A, but they were not significant after FDR correction. Results suggest that specific SLC15A4 gene variants might increase muscle carnosine content and improve meat quality. With a minor allele frequency of 0.17 for SNP c.658A>G in Yorkshire pigs, selection in favor of the c.658A allele may be considered as a mean to improve pork quality attributes., (Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.)

This study aimed to examine the influence of cooking methods and pre-determined refrigerated storage days on the production of lipid oxidation (TBARS), protein oxidation (PROTOX) and heterocyclic aromatic amines (HAA) in bacon. Forty-four pork bellies selected from pigs varying in breed, sex and diets to introduce variability in composition were processed as bacon. Sliced-bacon was stored at 4°C either for 2 or 28days and these storage groups were cooked either with microwave or frying pan. Microwave led to significantly higher PROTOX (P<0.001), while frying pan led to higher levels of HAA and TBARS in bacon (P<0.001). Frying pan cooking increased the saltiness and crispiness of bacon (P<0.05) whereas other sensory attributes were not affected (P>0.05) by the cooking methods and storage times. Similarly, the fatty acid composition of pork belly did not significantly influence the production of HAA, TBARS and PROTOX produced in bacon during cooking. Overall, microwave cooking had lesser impact on the production of carcinogenic compounds in bacon with only minor impact on sensory attributes., (Copyright © 2017. Published by Elsevier Ltd.)

We explored various dimensional and compositional factors that can influence the perception of pork belly firmness. Bellies from 198 pigs of three different genotypes, two sexes, two slaughter weights and three different diets were recovered and belly firmness was assessed using the belly-flop angle and a 5-point scale subjective measurement. Dimensional and compositional factors were recorded on intact and sheet-ribbed bellies. Subjective belly score was negatively correlated with belly-flop angle (r=-0.89). Regression analysis accounted for 77 and 83% of the variability in subjective belly firmness and belly-flop angle measurement, respectively. Belly length, weight and width influenced both measures of belly firmness, but these effects were more important for the belly-flop angle. After correcting flop angle using belly length, the effect of belly weight disappeared and the effect of other traits was more like those observed for subjective scoring. Hence, undue effect of belly length should be corrected for if this set-up is to be implemented in commercial plants., (Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.)

Muscle carnosine has pH-buffering, antioxidant and carbonyl scavenging properties, which may affect pork quality attributes. Study objectives were to: (1) compare muscle carnosine content and carnosine-related gene mRNA abundance in purebred pigs (n=282), (2) study the effect of muscle carnosine content on pork quality attributes and gene expression across breeds, and (3) study transcript abundance of carnosine-related genes in various tissues. Pigs were raised under similar conditions and slaughtered at 120±4.5kg. Longissimus thoracis muscles were sampled on the dressing line for gene expression and at 24h for meat quality measurements. Muscle carnosine content and carnosine-related gene mRNA abundance were modulated according to pig breeds. Greater pH24h, better water holding capacity and improved meat color values were found in pigs with high muscle carnosine content. Data suggest that high muscle carnosine is associated with improved pork meat quality attributes. The pig genetic background may be a key determinant for muscle carnosine content regulation., (Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.)

The accuracy of dual energy X-ray absorptiometry (DXA) in assessing carcass composition from pigs with diverse characteristics was examined in the present study. A total of 648 pigs from three different sire breeds, two sexes, two slaughter weights and three different diets were employed. DXA estimations were used to predict the dissected/chemical yield for lean and fat of carcass sides and primal cuts. The accuracy of the predictions was assessed based on coefficient of determination (R(2)) and residual standard deviation (RSD). The linear relationships for dissected fat and lean for all the primal cuts and carcass sides were high (R(2)>0.94, P<0.01), with low RSD (<1.9%). Relationships between DXA and chemical fat and lean of pork bellies were also high (R(2)>0.94, P<0.01), with RSD <2.9%. These linear relationships remained high over the full range of variation in the pig population, except for sire breed, where the coefficient of determination decreased when carcasses were classified based on this variable., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Single and combined effects of ractopamine supplementation (RAC, 7.5 vs. 0 ppm), castration method (surgical castration: SC vs. immuno-castration: IM) and genotype (genotype A: GA vs. GB containing 25% or 50% Piétrain) were determined on longissimus muscle (LM) fiber traits and quality of pork (n=512). RAC increased fiber IIX cross-sectional area (P=0.009) and decreased glycolytic potential (P=0.02) and pork tenderness (P<0.001). Fiber traits indicated that LM of IM pigs was more oxidative (P<0.05) and meat had slightly higher (P=0.04) off-flavor score and WBSF than SC. LM from GB pigs was paler (P<0.05) and had greater (P<0.05) glycolytic potential, IIX fiber cross sectional area and pork off-flavor than GA. RAC supplementation, castration method and genotype or their combination affected some fiber traits and some quality parameters but differences reported were small indicating these treatments or their combination could be used without major prejudice to meat quality., (Crown Copyright © 2014. Published by Elsevier Ltd. All rights reserved.)