The microstructure and micromechanics of the tendon-bone insertion.

The exceptional mechanical properties of the load-bearing connection of tendon to bone rely on an intricate interplay of its biomolecular composition, microstructure and micromechanics. Here we identify that the Achilles tendon-bone insertion is characterized by an interface region of ∼500 µm with a distinct fibre organization and biomolecular composition. Within this region, we identify a heterogeneous mechanical response by micromechanical testing coupled with multiscale confocal microscopy. This leads to localized strains that can be larger than the remotely applied strain. The subset of fibres that sustain the majority of loading in the interface area changes with the angle of force application. Proteomic analysis detects enrichment of 22 proteins in the interfacial region that are predominantly involved in cartilage and skeletal development as well as proteoglycan metabolism. The presented mechanisms mark a guideline for further biomimetic strategies to rationally design hard-soft interfaces.

Visual function improvement using photocromic and selective blue-violet light filtering spectacle lenses in patients affected by retinal diseases.

BACKGROUND: To evaluate functional visual parameters using photocromic and selective blue-violet light filtering spectacle lenses in patients affected by central or peripheral scotoma due to retinal diseases. Sixty patients were enrolled in this study: 30 patients affected by central scotoma, group 1, and 30 affected by peripheral scotoma, group 2. Black on White Best Corrected Visual Acuity (BW-BCVA), White on Black Best Corrected Visual Acuity (WB-BCVA), Mars Contrast Sensitivity (CS) and a Glare Test (GT) were performed to all patients. Test results with blue-violet filter, a short-pass yellow filter and with no filters were compared. RESULTS: All scores from test results increased significantly with blue-violet filters for all patients. The mean BW-BCVA increased from 0.30 ± 0.20 to 0.36 ± 0.21 decimals in group 1 and from 0.44 ± 0.22 to 0.51 ± 0.23 decimals in group 2 (Mean ± SD, p < 0.0001 in both cases). The mean WB-BCVA increased from 0.31 ± 0.19 to 0.38 ± 0.23 decimals in group 1 and from 0.46 ± 0.20 to 0.56 ± 0.22 decimals in group 2 (Mean ± SD, p < 0.0001 in both cases). The letter count for the CS test increased from 26.7 ± 7.9 to 30.06 ± 7.8 in group 1 (Mean ± SD, p = 0.0005) and from 31.5 ± 7.6 to 33.72 ± 7.3 in group 2 (Mean ± SD, p = 0.031). GT was significantly reduced: the letter count increased from 20.93 ± 5.42 to 22.82 ± 4.93 in group 1 (Mean ± SD, p < 0.0001) and from 24.15 ± 5.5 to 25.97 ± 4.7 in group 2 (Mean ± SD, p < 0.0001). Higher scores were recorded with the Blue filter compared to Yellow filter in all tests (p < 0.05). No significant differences in any test results could be detected between the Yellow filter and the No filter condition. CONCLUSIONS: The use of a combination of photocromic lens with a selective blue-violet light filter showed functional benefit in all evaluated patients.

Cataract and optic disk drusen in a patient with glycogenosis and di George syndrome: clinical and molecular report.

BACKGROUND: We report the ophthalmic findings of a patient with type Ia glycogen storage disease (GSD Ia), DiGeorge syndrome (DGS), cataract and optic nerve head drusen (ONHD). CASE PRESENTATION: A 26-year-old white woman, born at term by natural delivery presented with a post-natal diagnosis of GSD Ia. Genetic testing by array-comparative genomic hybridization (CGH) for DGS was required because of her low levels of serum calcium. The patient has been followed from birth, attending the day-hospital every six months at the San Paolo Hospital, Milan, outpatient clinic for metabolic diseases and previously at another eye center. During the last day-hospital visit, a complete eye examination showed ONHD and cataract in both eyes. Next Generation Sequencing (NGS) was subsequently done to check for any association between the eye problems and metabolic aspects. CONCLUSIONS: This is the first description of ocular changes in a patient with GSD Ia and DGS. Mutations explaining GSD Ia and DGS were found but no specific causative mutation for cataract and ONHD. The metabolic etiology of her lens changes is known, whereas the pathogenesis of ONHD is not clear. Although the presence of cataract and ONHD could be a coincidence; the case reported could suggest that hypocalcemia due to DGS could be the common biochemical pathway.

Biotyping of cultivable lactic acid bacteria isolated from donkey milk.

UNLABELLED: The diversity of lactic acid bacteria (LAB) species in donkey's milk was analysed by culture-dependent microbial techniques. Dominant strains were isolated on agar media generally used for enumerating LAB. To enrich the number of acidifying LAB present, the milk samples were incubated at 37°C for 24 h (cultured milk samples, CM). One of the CM samples was heat-treated at 63°C for 10 min before incubation at 37°C (heat-treated and cultured milk sample, TCM) to select thermophilic LAB. The microflora in these CM and TCM samples was then compared to that of the raw milk samples (RM). Among the 129 LAB isolates, 10 different species (four Enterococcus, five Streptococcus and one Pediococcus) were identified by molecular methods. Although the 10 LAB species were present in the RM samples, only three and two isolates were found in CM and TCM samples, respectively. Despite the selection protocol being set up to favour the isolation of all LAB isolates present in donkey milk, relatively few species and biotypes were isolated. No LAB isolates belonging to the most technologically important dairy starter species were detected. The possible factors related to the limited LAB diversity in donkey's milk have been discussed below. SIGNIFICANCE AND IMPACT OF THE STUDY: There is increased interest in using donkey's milk as a source of human nutrition. The large amounts of antimicrobial components and defence factors present in donkey's milk provide protection from microbial infections and distinguish donkey's milk from the milks of other mammals. However, the microbiota in donkey's milk has so far been poorly characterized, specifically with regard to the lactic acid bacteria (LAB). This study has identified cultivable, acidifying and thermoduric LAB that could be used to develop starter cultures. This is the first study to investigate the culturable LAB microbiota present in donkey's milk.

Syndromic and non-syndromic forms of retinitis pigmentosa: a comprehensive Italian clinical and molecular study reveals new mutations.

Mutations in more than 60 different genes have been associated with non-syndromic and syndromic retinitis pigmentosa (RP), a heterogeneous group of inherited retinal dystrophies. To increase the understanding of the molecular epidemiology of the disease in Italy, we analyzed 56 patients with syndromic and non-syndromic forms of RP attending the Retinitis Pigmentosa Center of San Paolo Hospital (Milan, Italy). Patients underwent detailed clinical examination. Genomic DNA isolated from peripheral blood samples was screened for mutations in different genes according to RP form by direct sequencing analysis. The impact of novel missense mutations on protein functions was predicted by in silico analysis and protein sequence alignment. Cosegregation analysis was performed between available family members. Forty-one of the 56 probands analyzed had non-syndromic and 15 had syndromic RP forms. Putative disease-causing mutations were identified in 19 of 56 unrelated RP probands. Mutation screening identified a total of 22 different heterozygous variants. Notably, 12 of these putative pathogenic mutations have not been previously reported. New variants were found to be located on the USH2A, RPGR, EYS, and RHO genes. All 3 new variants detected in X-linked RP probands were confirmed in other affected family members. We found a positivity rate of 24.4% and 60% for probands with non-syndromic and syndromic RP, respectively. This is the first report of RPGR X-linked RP proband-ORF15 mutations in Italian patients with X-linked (XL)-RP. In addition, this is the first report of data regarding the association between EYS mutations and non-syndromic RP forms in the Italian population.

Retraction Note: Autoantibodies detection in patients affected by autoimmune retinopathies.

The article "Autoantibodies detection in patients affected by autoimmune retinopathies", by M.R. Ceccarini, M.C. Medori, K. Dhuli, S. Tezzele, G. Bonetti, C. Micheletti, P.E. Maltese, S. Cecchin, K. Donato, L. Colombo, L. Rossetti, G. Staurenghi, A.P. Salvetti, M. Oldani, L. Ziccardi, D. Marangoni, G. Iarossi, B. Falsini, G. Placidi, F. D'Esposito, F. Viola, M. Nassisi, G. Leone, L. Cimino, L. De Simone, V. Mastrofilippo, T. Beccari, M. Bertelli, published in Eur Rev Med Pharmacol Sci 2023; 27 (6 Suppl): 57-63-DOI: 10.26355/eurrev_202312_34690-PMID: 38112948 has been retracted by the Editor in Chief for the following reasons. Following some concerns raised on PubPeer, the Editor in Chief has started an investigation to assess the validity of the results. The outcome of the investigation revealed that the manuscript presented major flaws in the following: -       Issues with ethical approval -       Undeclared conflict of interest In light of concerns regarding the potential manipulation of Supplementary Figure 2, the journal's inquiry has been unable to conclusively determine whether the alterations noted on PubPeer constitute figure manipulation. The investigation yielded divergent evaluations. However, given the aforementioned concerns, the Editor in Chief doubts the integrity of the findings presented and thus, has opted to retract the article. The authors disagree with this retraction. This article has been retracted. The Publisher apologizes for any inconvenience this may cause. https://www.europeanreview.org/article/34690.

Factor VIII genotype characterization of haemophilia A affected patients with transient and permanent inhibitors: a comprehensive Argentine study of inhibitor risks.

Inhibitor development against exogenous factor VIII is a severe impairment of replacement therapy affecting 18% of Argentine patients with severe haemophilia A (HA). To study the molecular predisposition for inhibitor development, we genotyped 260 HA patients with and without inhibitors, countrywide. The inhibitor-positive population (19 transients, 15 low responders, LR and 70 high responders, HR) of 104 severe-HA patients showed 59 Inv22 (intron 22 inversions), 18 small ins/del-frameshifts, 12 gross deletions, 12 nonsense, one splicing defect and two missense, p.Arg531Pro and p.Leu575Pro, both LR and thought to impair FVIII A2 domain secondary structure. In addition, a patient with mild HA and HR showed the missense p.Glu1704Lys associated with two neutral intronic substitutions potentially affecting the A3 domain. A case/control study (84/143) permitted estimation of F8 genotype-specific inhibitor risks [OR; prevalence (CI)] in severe-HA patients classifying a high-risk group including multi-exon deletions [3.66; 55% (19-100)], Inv22 [1.8; 24% (19-100)] and nonsense in FVIII-LCh [1.2; 21% (7-59)]; an average risk group including single-exon deletions, indel frameshifts and nonsense-HCh; and a low-risk group represented by missense defects [0.14; 3% (0.6-11)]. Analysis of inhibitor concordance/discordance in related patients indicated additional genetic factors other than F8 genotype for inhibitor formation. No significant inhibitor-predisposing factors related to FVIII product exposure were found in age- and F8 genotype-stratified populations of severe-HA patients. In conclusion, the Argentine HA patient series presents similar global and mutation-specific inhibitor risks than the HA database and other published series. This case-specific information will help in designing fitted therapies and follow-up protocols in Argentina.

Citicoline oral solution in glaucoma: is there a role in slowing disease progression?

PURPOSE: To assess the effect of citicoline on visual field rates of progression in patients with progressing glaucoma. PATIENTS AND METHODS: Forty-one patients with a diagnosis of progressing glaucoma received citicoline in oral solution for 2 years. Included were patients with a disease progression of at least -1 dB/year (at MD, mean deviation) for at least 3 years before entering the study despite controlled intraocular pressure (IOP). Patients were followed with 4 visual field examinations per year for 2 years. RESULTS: At baseline, the mean rate of progression was -1.1 (±0.7) dB/year despite the fact that the IOP had been below 18 mm Hg for at least 3 years. At study inclusion, the mean IOP was 15.5 (±2.6) mm Hg and the mean MD was -9.2 (±6.7) dB in the worst eye. Starting from the first cycle of treatment with citicoline, the mean rate of progression significantly changed to -0.15 (±0.3) dB/year at the end of the study (p = 0.01). CONCLUSIONS: This study seems to indicate that supplementation with citicoline might significantly slow down glaucomatous rates of progression.

Autoantibodies detection in patients affected by autoimmune retinopathies.

OBJECTIVE: Autoimmune retinopathies (ARs) encompass a spectrum of immune diseases that are characterized by the presence of autoantibodies against retinal proteins in the bloodstream. These autoantibodies (AAbs) lead to a progressive and sometimes rapid loss of vision. ARs commonly affect subjects over 50 years of age, but also rare cases of kids under 3 years of age have been reported. PATIENTS AND METHODS: In this study, 47 unrelated Caucasian patients were enrolled. All subjects showed negative cancer diagnoses and negative results in their genetic screenings. We studied 8 confirmed retinal antigens using Western blotting analysis, with α-enolase followed by carbonic anhydrase II being the two most frequently found in the patients' sera. RESULTS: Nineteen patients were positive (40.4%), thirteen uncertain (27.7%), and fifteen were negative (31.9%). Their gender did not correlate with the presence of AAbs (p=0.409). CONCLUSIONS: AAbs are responsible for retinal degeneration in some cases, while in others, they contribute to exacerbating the progression of the disease; however, their detection is crucial to reaching a better diagnosis and developing more effective treatments for these conditions. Moreover, finding good biomarkers is important not only for AR monitoring and prognosis, but also for helping with early cancer diagnosis.

Informativeness of a novel multiallelic marker-set comprising an F8 intron 21 and three tightly linked loci for haemophilia A carriership analysis.

The extraordinary heterogeneous nature of the deleterious mutations in the F8 gene that lead to functional deficiency of clotting factor VIII in haemophilia A makes routine direct mutation profiling difficult. When direct mutation analysis cannot be performed or a causative/candidate mutation is not found, a second-line approach to track the defective F8 gene within at-risk families is linkage genetic analysis with, tried-and-tested, F8-intragenic and/or extragenic non-recombining multiallelic short tandem repeats (STR). Although several typing STR loci within and around F8 have been described, there is need for improving assessment, because the combined informativeness of available assays rarely reaches 100%. Here, we characterized a newly identified 0.28 cM-resolution marker-set, consisting of a dinucleotide STR located on F8 intron 21 (F8Int21; [AC](n)) and three extragenic tetranucleotide STR located on GAB3 intron 1 (GAB3Int1; [TAAA](n)) and TMLHE intron 1 (TMLHEInt1.1; [GAAA](n) and TMLHEInt1.3; [ATTC](n)). Heterozygosity rates determined in 100 unrelated females ranged from 0.25 (GAB3Int1) to 0.63 (F8Int21). The set rendered a combined informativeness of 0.91 for at least one marker and 0.60 for a minimum of two loci, with at least one F8-intragenic. Multiallelic interlocus non-random association analysis revealed that GAB3Int1 is not in significant gametic disequilibrium (GD) with F8Int21, F8Int9.2, TMLHEInt1.3 or TMLHEInt1.1. Gametic disequilibrium breakdown attests historical recombination between GAB3Int1 and the F8 gene. Through computational analysis of reference assembly sequence data, we note in the GD breakdown region and in the F8 gene a higher than average density of the 13-mer CCNCCNTNNCCNC consensus motif, commonly associated with recombination hotspots.

The effect of leptin on Lep expression is tissue-specific and nutritionally regulated.

Leptin, the product of the Obese (Lep) gene, orchestrates behavioral and metabolic responses to nutrient intake. Here, we demonstrate tissue-specific autoregulation of Lep. Moderate increases in circulating leptin considerably decreased Lep expression in adipose tissue and induced lep expression in skeletal muscle, a tissue that normally does not express this gene. Changes in nutrient availability resulted in rapid alterations in Lep autoregulation. These findings demonstrate negative feedback regulation of Lep in fat, and indicate that leptin secretion can function as a vehicle of 'cross-talk' between adipose tissue and skeletal muscle, leading to tissue-specific modulation of the 'leptin signal'.

Isolation and phenotypic characterization of Lactobacillus casei and Lactobacillus paracasei bacteriophage-resistant mutants.

AIMS: To isolate and characterize bacterial strains derived from Lactobacillus casei and Lactobacillus paracasei strains and resistant to phage MLC-A. METHODS AND RESULTS: Two of nine assayed strains rendered resistant mutants with recovery efficiencies of 83% (Lact. paracasei ATCC 27092) and 100% (Lact. casei ATCC 27139). DNA similarity coefficients (RAPD-PCR) confirmed that no significant genetic changes occurred while obtaining resistant mutants. Neither parent nor mutant strains spontaneously released phages. Phage-resistant mutants were tested against phages PL-1, J-1, A2 and MLC-A8. Lactobacillus casei ATCC 27092 mutants showed, overall, lower phage resistance than Lact. paracasei ATCC 27092 ones, but still higher than that of the parent strain. Lactobacillus paracasei ATCC 27092 mutants moderately adsorbed phage MLC-A only in calcium presence, although their parent strain successfully did it with or without calcium. Adsorption rates for Lact. casei ATCC 27139 and its mutants were highly influenced by calcium. Again, phage adsorption was higher on the original strain. CONCLUSIONS: Several isolates derived from two Lact. casei and Lact. paracasei strains showed resistance to phage MLC-A but also to other Lact. casei and Lact. paracasei phages. SIGNIFICANCE AND IMPACT OF THE STUDY: This study highlights isolation of spontaneous bacteriophage-resistant mutants from Lact. casei and Lact. paracasei as a good choice for use in industrial rotation schemes.

Boar sperm functionality is related to α-tocopherol content after freezing-thawing.

Boar spermatozoa are sensitive to oxidative damage produced during cryopreservation. Our aim was to evaluate the participation of different antioxidants in the improvement of cryopreserved boar sperm functionality. Spermatozoa frozen with 200 µg ml(-1) α-tocopherol, 0.5 mm 17ß-oestradiol or seminal plasma were used to evaluate sperm parameters and capacitation-like changes. The 17ß-oestradiol and α-tocopherol concentrations were assessed by RIA and HPLC respectively. Motility was improved but lipid peroxidation and capacitation-like changes were diminished (P < 0.05) in antioxidant samples. A significant increase in 17ß-oestradiol concentration was detected in 17ß-oestradiol or seminal plasma samples. Alpha-tocopherol content increased in α-tocopherol, 17ß-oestradiol or seminal plasma samples, obtaining the lowest level in the α-tocopherol ones. The 17ß-oestradiol or seminal plasma components may be acting in the regeneration of the α-tocopherol antioxidant capacity. The α-tocopherol concentration may be conditioning the cryopreserved boar sperm functionality. The addition of antioxidants could be useful to reduce oxidative stress, thus improving the functionality of cryopreserved boar spermatozoa.

Differential effects of hypothalamic long-chain fatty acid infusions on suppression of hepatic glucose production.

Our objective was to investigate whether the direct bilateral infusion of the monounsaturated fatty acid (MUFA) oleic acid (OA) within the mediobasal hypothalamus (MBH) is sufficient to reproduce the effect of administration of OA (30 nmol) in the third cerebral ventricle, which inhibits glucose production (GP) in rats. We used the pancreatic basal insulin clamp technique (plasma insulin ∼20 mU/ml) in combination with tracer dilution methodology to compare the effect of MBH OA on GP to that of a saturated fatty acid (SFA), palmitic acid (PA), and a polyunsaturated fatty acid (PUFA), linoleic acid (LA). The MBH infusion of 200 but not 40 pmol of OA was sufficient to markedly inhibit GP (by 61% from 12.6 ± 0.6 to 5.1 ± 1.6 mg·kg(-1)·min(-1)) such that exogenous glucose had to be infused at the rate of 6.0 ± 1.2 mg·kg(-1)·min(-1) to prevent hypoglycemia. MBH infusion of PA also caused a significant decrease in GP, but only at a total dose of 4 nmol (GP 5.8 ± 1.6 mg·kg(-1)·min(-1)). Finally, MBH LA at a total dose of 0.2 and 4 nmol failed to modify GP compared with rats receiving MBH vehicle. Increased availability of OA within the MBH is sufficient to markedly inhibit GP. LA does not share the effect of OA, whereas PA can reproduce the potent effect of OA on GP, but only at a higher dose. It remains to be determined whether SFAs need to be converted to MUFAs to exert this effect or whether they activate a separate signaling pathway to inhibit GP.

Efficacy of the fixed combinations of bimatoprost or latanoprost plus timolol in patients uncontrolled with prostaglandin monotherapy: a multicenter, randomized, investigator-masked, clinical study.

PURPOSE: To compare the efficacy and tolerability of a once-daily evening dose of bimatoprost/timolol fixed combination (BTFC) with that of a once-daily evening dose of latanoprost/timolol fixed combination (LTFC) in patients not controlled with prostaglandins analogues monotherapy. METHODS: A total of 82 patients on prostaglandin analogues monotherapy were enrolled in this prospective, multicenter, investigator masked, clinical study and were randomized to either BTFC (n=47) or LTFC (n=35) topical therapy once at night for 12 weeks. The primary endpoint of the study was to compare the mean daily intraocular pressure (IOP) reduction from baseline between the two treatment arms. Secondary endpoints included the mean daily IOP at 1 and 3 months compared to baseline and the percentage of patients showing a mean IOP reduction from baseline greater than or equal to 15% or 20%. RESULTS: Mean IOP at baseline was 22.7+/-2.0 and 22.1+/-2.6 mmHg in the BTFC and LTFC groups, respectively (p=0.23). Both treatments were effective in reducing the IOP from baseline. The mean IOP reduction was significantly greater in the BTFC group than in the LTFC group (-21.4% vs -13.7%, p<0.001). A higher percentage of patients in the BTFC group showed a mean IOP reduction from baseline >or=15% (72.3% vs 40.0%) and >or=20% (61.7% vs 17.1%) compared to patients in the LTFC group. CONCLUSIONS: Both BTFC and LTFC were more effective versus the monotherapy with prostaglandin analogues. BTFC demonstrated higher performance than LTFC in terms of relative IOP reduction.

Optical coherence tomography angiography in Purtscher-like retinopathy associated with dermatomyositis: a case report.

PURPOSE: To describe a multimodal imaging diagnosis of retinopathy in dermatomyositis. CASE PRESENTATION: A 21-year-old white woman with a history of fatigue and a cutaneous rash complained of visual impairment in her left eye. A funduscopic examination showed multiple confluent cotton-wool spots in both eyes. Swept source-optical coherence tomography presented macular edema in both eyes; optical coherence tomography angiography revealed superficial and deep capillary occlusion in all areas affected by cotton-wool spots; and fluorescein angiography showed vascular walls enhancement, veins dilatation, and capillary leakage. After large doses of intravenously administered glucocorticoid therapy, followed by a cyclophosphamide regimen, best corrected visual acuity returned to 20/20 in both eyes. CONCLUSIONS: This case report presents optical coherence tomography angiography clinical findings in a rare case of dermatomyositis-associated retinopathy, remarking the importance of a multi-imaging approach for a correct diagnosis and treatment of eye injuries, in order to avoid serious complications and permanent sequelae.

The effect of pneumatic trabeculoplasty on intraocular pressure: the results of a 6-month, open-label, multicenter study.

PURPOSE: To evaluate the effects of pneumatic trabeculoplasty (PNT) in ocular hypertension and glaucoma subjects. METHODS: A total of 63 consecutive subjects, either treated (79%) or untreated (21%), with intraocular pressure (IOP) between 20 and 25 mmHg were enrolled; the eye with higher IOP (or, in case of identical IOP, worse visual field) was treated with PNT, with the fellow eye used as control. Subjects underwent a baseline evaluation the day before treatment, two PNT treatments at day 0 and 7, visits at day 1, 8, 14, and at each month until the end of the study, which lasted 6 months. Safety was addressed at all visits; an IOP curve (at 8 and 10 AM, 2 and 4 PM) was obtained at baseline and during monthly visits. RESULTS: In PNT eyes, baseline IOP was 22.2-/+1.6 mmHg. Following PNT a statistically significant reduction of IOP occurred at all visits (p<0.0001), with a mean decrease ranging from -2.7-/+2.5 (-11.9-/+10.8%) to -3.6-/+2.6 mmHg (-16.0-/+11.6%); mean reduction was 12.8-/+11.5%. Although IOP diminished also in the control eyes after baseline (p<0.05), the change in IOP was significantly higher in PNT group at each visit (p<0.05). Mild side effects were experienced by 76% of subjects and they all resolved without sequelae. CONCLUSIONS: The results suggest the effect of this procedure in reducing IOP in glaucoma and ocular hypertensive subjects.

Antioxidant consumption and development of oxidation during ageing of buffalo meat produced in Argentina.

Buffalo meat production is increasing in Argentina. Information on meat quality and nutritional value will be useful in marketing. This work describes the oxidative stability of the Longissimus dorsi (LD) in relation to consumption of antioxidant vitamins, fatty acid composition and color deterioration during ageing. Vitamins levels found in fresh beef were 4.22±0.93; 0.24±0.05 and 0.25±0.06µg/g for α- and γ-tocopherol, and ß-carotene, respectively. Vitamin loss was almost 90% throughout an ageing period of 25 days at 2°C. Concomitantly, TBARS levels increased from 0.076±0.018 to 0.14 6±0.032mg MDA/kg beef. Hexanal and pentanal levels were low and no correlations with oxidation were detected (P>0.05). The predominant color changes in aged beef were reduced redness and yellowness with an increase in lightness (P<0.05). Vitamin levels and TBARS were used to develop a prediction equation for post-mortem aging.