P5630Morphometric and qualitative differences in neointimal tissue six months after implantation of bioresorbable scaffolds versus conventional everolimus eluting stents in ISAR-Absorb MI trial

2019 ◽  
Vol 40 (Supplement_1) ◽  
Author(s):  
H Rai ◽  
F Alfonso ◽  
M Maeng ◽  
C Bradaric ◽  
J Wiebe ◽  
...  
Keyword(s):  
Cross Sections ◽  
Mixed Model ◽  
Linear Mixed Model ◽  
Metallic Stent ◽  
Bioresorbable Scaffolds ◽  
Generalised Linear Mixed Model ◽  
Neointimal Coverage ◽  
Novel Devices

Abstract Background Bioresorbable scaffolds (BRS) are novel devices designed to overcome the long-term limitations of permanent metallic stent implantation. Optical coherence tomography (OCT) surveillance can provide important insights on the process of vessel wall healing at follow-up. Purpose We sought to compare OCT-assessed healing at 6 months after implantation of everolimus-eluting BRS and everolimus-eluting metallic stents (EES) in patients treated for acute myocardial infarction (AMI). Methods ISAR-Absorb MI is a multicentre, 2:1 randomized trial comparing outcomes of patients with AMI stented with BRS or conventional EES. Angiographic surveillance was planned for all patients at 6–8 months follow-up. Patients who had OCT surveillance at follow-up were included for the present analysis. Analysis of contiguous OCT cross-sections- 1 mm apart was performed at a centralized core laboratory. Tissue characterisation using a 256-level grey-scale signal intensity (GSI) analysis was also performed for all neointimal regions of interest (ROI) with thickness of 100 to 400 μm. ROI's were classified as mature using a standard cut-off GSI score of 109.7. Generalised linear mixed model (GLMM) was used as appropriate. Statistical analysis was performed using R software. Data is presented as numbers, percentages or median (Interquartile range, IQR). Results Median follow-up interval was 216 days. 70 patients in the BRS arm and 33 patients in the EES arm were available for analysis. Stented length was 19.8 mm (13.6, 24.5) and 22.3 mm (16.7, 26.4) in BRS and EES arms respectively (p=0.73). Minimum lumen area [5.13 (3.95, 6.71) vs. 4.83 (3.63, 6.92) mm2] and minimum stent area [5.78 (4.88, 7.34) vs. 6.36 (4.70, 7.45) mm2] were comparable between BRS and EES. 2,262 frames (1,529 in BRS, 733 in EES) with 20,033 struts (12,704 in BRS, 7,329 in EES) were assessed. Overall strut coverage was better with BRS compared to EES (97.5% vs. 91.1% respectively, p<0.001). Malapposed (1.1% vs. 0.5%, p=0.54) and uncovered struts (7.3% vs. 1.3%, p<0.001) were more common with EES. Neointimal coverage was comparable amongst both stent groups [85.5 (61.9, 124.1) vs. 71.5 (33.4, 133.0) μm in BRS and EES groups respectively, p=0.50]. GSI analysis in 95 cases (65 cases, 2,233 ROIs in BRS; 30 cases, 1,210 ROIs in EES) showed that immature ROIs were numerically more common in the EES group as compared to the BRS group (75.4 vs. 57.0% respectively; p=0.35). Two-year clinical follow-up and analysis of correlation of clinical outcomes with OCT findings will also be available for presentation at ESC Congress 2019. Conclusions In selected patients undergoing OCT imaging at 6–8 months after implantation of BRS and conventional EES for AMI, we observed generally favourable healing characteristics with high rates of strut coverage, low rates of strut malapposition and fewer areas of immature neointimal areas with BRS in comparison to EES. Acknowledgement/Funding The study was predominantly funded by Deutsches Herzzentrum München and in part by a grant from Abbott Vascular

Long-term seizure outcomes after pediatric temporal lobectomy: does brain MRI lesion matter?

2019 ◽  
Vol 24 (2) ◽  
pp. 200-208
Author(s):  
Ravindra Arya ◽  
Francesco T. Mangano ◽  
Paul S. Horn ◽  
Sabrina K. Kaul ◽  
Serena K. Kaul ◽  
...  
Keyword(s):  
Repeated Measures ◽  
Mixed Model ◽  
Linear Mixed Model ◽  
Hippocampal Sclerosis ◽  
Brain Mri ◽  
Temporal Lobectomy ◽  
Seizure Freedom ◽  
Seizure Onset

OBJECTIVEThere is emerging data that adults with temporal lobe epilepsy (TLE) without a discrete lesion on brain MRI have surgical outcomes comparable to those with hippocampal sclerosis (HS). However, pediatric TLE is different from its adult counterpart. In this study, the authors investigated if the presence of a potentially epileptogenic lesion on presurgical brain MRI influences the long-term seizure outcomes after pediatric temporal lobectomy.METHODSChildren who underwent temporal lobectomy between 2007 and 2015 and had at least 1 year of seizure outcomes data were identified. These were classified into lesional and MRI-negative groups based on whether an epilepsy-protocol brain MRI showed a lesion sufficiently specific to guide surgical decisions. These patients were also categorized into pure TLE and temporal plus epilepsies based on the neurophysiological localization of the seizure-onset zone. Seizure outcomes at each follow-up visit were incorporated into a repeated-measures generalized linear mixed model (GLMM) with MRI status as a grouping variable. Clinical variables were incorporated into GLMM as covariates.RESULTSOne hundred nine patients (44 females) were included, aged 5 to 21 years, and were classified as lesional (73%), MRI negative (27%), pure TLE (56%), and temporal plus (44%). After a mean follow-up of 3.2 years (range 1.2–8.8 years), 66% of the patients were seizure free for ≥ 1 year at last follow-up. GLMM analysis revealed that lesional patients were more likely to be seizure free over the long term compared to MRI-negative patients for the overall cohort (OR 2.58, p < 0.0001) and for temporal plus epilepsies (OR 1.85, p = 0.0052). The effect of MRI lesion was not significant for pure TLE (OR 2.64, p = 0.0635). Concordance of ictal electroencephalography (OR 3.46, p < 0.0001), magnetoencephalography (OR 4.26, p < 0.0001), and later age of seizure onset (OR 1.05, p = 0.0091) were associated with a higher likelihood of seizure freedom. The most common histological findings included cortical dysplasia types 1B and 2A, HS (40% with dual pathology), and tuberous sclerosis.CONCLUSIONSA lesion on presurgical brain MRI is an important determinant of long-term seizure freedom after pediatric temporal lobectomy. Pediatric TLE is heterogeneous regarding etiologies and organization of seizure-onset zones with many patients qualifying for temporal plus nosology. The presence of an MRI lesion determined seizure outcomes in patients with temporal plus epilepsies. However, pure TLE had comparable surgical seizure outcomes for lesional and MRI-negative groups.

scholarly journals Improved cephalic index following early cranial vault remodeling in patients with isolated nonsyndromic sagittal synostosis

2021 ◽  
Vol 50 (4) ◽  
pp. E7
Author(s):  
Arvid Frostell ◽  
Maryam Haghighi ◽  
Jiri Bartek ◽  
Ulrika Sandvik ◽  
Bengt Gustavsson ◽  
...  
Keyword(s):  
Mixed Model ◽  
Linear Mixed Model ◽  
Cranial Vault ◽  
Hospital Length Of Stay ◽  
Cephalic Index ◽  
Sagittal Synostosis ◽  
The Mean ◽  
Cranial Vault Remodeling

OBJECTIVE Isolated nonsyndromic sagittal synostosis (SS) is the most common form of craniosynostosis in children, accounting for approximately 60% of all craniosynostoses. The typical cranial measurement used to define and follow SS is the cephalic index (CI). Several surgical techniques have been suggested, but agreement on type and timing of surgery is lacking. This study aimed to evaluate the authors’ institutional experience of surgically treating SS using a modified subtotal cranial vault remodeling technique in a population-based cohort. Special attention was directed toward the effect of patient age at time of surgery on long-term CI outcome. METHODS A retrospective analysis was conducted on all patients with isolated nonsyndromic SS who were surgically treated from 2003 to 2011. Data from electronic medical records were gathered. Eighty-two patients with SS were identified, 77 fulfilled inclusion criteria, and 72 had sufficient follow-up data and were included. CI during follow-up after surgery was investigated with ANOVA and a linear mixed model. RESULTS In total, 72 patients were analyzed, consisting of 16 females (22%) and 56 males (78%). The mean ± SD age at surgery was 4.1 ± 3.1 months. Blood transfusions were received by 81% of patients (26% intraoperatively, 64% postoperatively, 9% both). The mean ± SD time in the pediatric ICU was 1.1 ± 0.25 days, and the mean ± SD total hospital length of stay was 4.6 ± 2.0 days. No patient required reoperation. The mean ± SD CI increased from 69 ± 3 to 87 ± 5 for patients who underwent surgery before 45 days of age. Surgery resulted in a larger increase in CI for patients who underwent surgery at a younger age compared with older patients (p < 0.05, Tukey’s HSD test). In the comparison of patients who underwent surgery before 45 days of age with patients who underwent surgery at 45–90, 90–180, and more than 180 days of age, the linear mixed model estimated a long-term loss of CI of 3.0, 5.5, and 7.4 points, respectively. CONCLUSIONS The modified subtotal cranial vault remodeling technique used in this study significantly improved CI in patients with SS. The best results were achieved when surgery was performed early in life.

scholarly journals Thalamic white matter macrostructure and subnuclei volumes in Parkinson’s disease depression

2022 ◽  
Vol 8 (1) ◽  
Author(s):  
R. Bhome ◽  
A. Zarkali ◽  
G. E. C. Thomas ◽  
J. E. Iglesias ◽  
J. H. Cole ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
White Matter ◽  
Mixed Model ◽  
Linear Mixed Model ◽  
Neural Structure ◽  
Generalised Linear Mixed Model ◽  
Antidepressant Use ◽  
The Relationship

AbstractDepression is a common non-motor feature of Parkinson’s disease (PD) which confers significant morbidity and is challenging to treat. The thalamus is a key component in the basal ganglia-thalamocortical network critical to the pathogenesis of PD and depression but the precise thalamic subnuclei involved in PD depression have not been identified. We performed structural and diffusion-weighted imaging (DWI) on 76 participants with PD to evaluate the relationship between PD depression and grey and white matter thalamic subnuclear changes. We used a thalamic segmentation method to divide the thalamus into its 50 constituent subnuclei (25 each hemisphere). Fixel-based analysis was used to calculate mean fibre cross-section (FC) for white matter tracts connected to each subnucleus. We assessed volume and FC at baseline and 14–20 months follow-up. A generalised linear mixed model was used to evaluate the relationship between depression, subnuclei volume and mean FC for each thalamic subnucleus. We found that depression scores in PD were associated with lower right pulvinar anterior (PuA) subnucleus volume. Antidepressant use was associated with higher right PuA volume suggesting a possible protective effect of treatment. After follow-up, depression scores were associated with reduced white matter tract macrostructure across almost all tracts connected to thalamic subnuclei. In conclusion, our work implicates the right PuA as a relevant neural structure in PD depression and future work should evaluate its potential as a therapeutic target for PD depression.

Symptomatic Relief is Related to Serum Free Triiodothyronine Concentrations during Follow-up in Levothyroxine-Treated Patients with Differentiated Thyroid Cancer

2018 ◽  
Vol 126 (09) ◽  
pp. 546-552 ◽  
Author(s):  
Rolf Larisch ◽  
John Midgley ◽  
Johannes Dietrich ◽  
Rudolf Hoermann
Keyword(s):  
Mixed Model ◽  
Clinical Decision Making ◽  
Linear Mixed Model ◽  
Reference Range ◽  
Symptomatic Relief ◽  
Symptom Relief ◽  
Multivariable Analysis ◽  
Free Triiodothyronine ◽  
Generalised Linear Mixed Model

Abstract Aim Patients on levothyroxine-treatment frequently have complaints although TSH is within the reference range. Moreover, FT3 is often low in these patients. The clinical significance of this disequilibrium is studied here. Patients, methods We conducted a retrospective longitudinal study including 319 patients with differentiated thyroid carcinoma on LT4-medication (1.8 [1.6,2.1] µg/kg body weight). Patients were followed at 2309 visits for at median 63 [46,81] months. Association of reported complaints during follow-up with changes in thyroid parameters were analysed using a generalised linear mixed model accounting for within-variability and intra-subject correlations. Results 26% of patients expressed hypothyroid and 9.7% hyperthyroid complaints at any one visit, rates per visit being 6.5% and 2%, respectively. During follow-up, median changes in spans were as follows, LT4-dose 0.49 [IQR 0.29,0.72] µg/kg, FT3 1.77 [1.25,2.32] pmol/l, FT4 9.80 [6.70,12.8] pmol/l and TSH 1.25 [0.42,2.36] mIU/l. While rates of both hypothyroid or hyperthyroid symptoms were significantly related to all three thyroid parameters, the relationship of hypothyroid symptoms with FT3 extended to a below reference TSH range. Hypothyroid symptom relief was associated with both a T4 dose giving TSH-suppression below the lower reference limit and FT3 elevated further into the upper half of its reference range. In multivariable analysis, relationships between complaints and FT3 concentrations remained significant after adjusting for gender, age and BMI. Conclusion Residual hypothyroid complaints in LT4-treated patients are specifically related to low FT3 concentrations. This supports an important role of FT3 for clinical decision making on dose adequacy, particularly in symptomatic athyreotic patients.

Temporalis muscle thickness as an indicator of sarcopenia is associated with long-term motor outcomes in Parkinson’s disease

2021 ◽  
Author(s):  
Seok Jong Chung ◽  
Yun Joong Kim ◽  
Han Soo Yoo ◽  
Jin Ho Jung ◽  
KyoungWon Baik ◽  
...  
Keyword(s):  
Regression Models ◽  
Mixed Model ◽  
Linear Mixed Model ◽  
Cox Regression ◽  
Muscle Thickness ◽  
Temporalis Muscle ◽  
Wearing Off ◽  
Motor Outcomes

Abstract Background To investigate the relationship between temporalis muscle thickness (TMT) at baseline as a surrogate marker for sarcopenia and long-term motor outcomes in patients with Parkinson’s disease (PD). Methods We enrolled 249 patients with drug-naïve early-stage PD (119 males and 130 females, follow-up &gt; 3 years). Baseline TMT of each patient was measured on the axial plane of T1-weighted images. The association between baseline TMT and long-term motor outcomes in PD was assessed using Cox regression models for levodopa-induced dyskinesia (LID), wearing-off, and freezing of gait (FOG) and a linear mixed model for the longitudinal increases in levodopa-equivalent dose (LED) per body weight over time. Statistical analyses were performed separately for sex if an interaction effect between TMT and sex was assumed. Results TMT differed substantially between the sexes, and male PD patients had higher TMT (6.69 ± 1.39 mm) than female PD patients (5.64 ± 1.34 mm, p &lt; 0.001). Cox regression models demonstrated that baseline TMT was not associated with the risk of developing LID, wearing-off, or FOG during the follow-up period. The linear mixed model was applied separately for sex and demonstrated that higher TMT at baseline was associated with slower increases in LED per body weight in male PD patients, but not in female PD patients. Conclusions This study demonstrated that baseline TMT could be an indicator of the longitudinal requirement for dopaminergic medications in male patients with PD, suggesting that sarcopenia may have a detrimental effect on disease progression in PD in a sex-specific manner.

scholarly journals Long-term follow-up including extensive complement analysis of a pediatric C3 glomerulopathy cohort

2021 ◽  
Author(s):  
Marloes A. H. M. Michels ◽  
Kioa L. Wijnsma ◽  
Roel A. J. Kurvers ◽  
Dineke Westra ◽  
Michiel F. Schreuder ◽  
...  
Keyword(s):  
Mixed Model ◽  
Linear Mixed Model ◽  
Immunosuppressive Treatment ◽  
Complement C3 ◽  
C3 Glomerulopathy ◽  
Laboratory Findings ◽  
Mixed Model Analysis ◽  
Long Term Follow Up

Abstract Background C3 glomerulopathy (C3G) is a rare kidney disorder characterized by predominant glomerular depositions of complement C3. C3G can be subdivided into dense deposit disease (DDD) and C3 glomerulonephritis (C3GN). This study describes the long-term follow-up with extensive complement analysis of 29 Dutch children with C3G. Methods Twenty-nine C3G patients (19 DDD, 10 C3GN) diagnosed between 1992 and 2014 were included. Clinical and laboratory findings were collected at presentation and during follow-up. Specialized assays were used to detect rare variants in complement genes and measure complement-directed autoantibodies and biomarkers in blood. Results DDD patients presented with lower estimated glomerular filtration rate (eGFR). C3 nephritic factors (C3NeFs) were detected in 20 patients and remained detectable over time despite immunosuppressive treatment. At presentation, low serum C3 levels were detected in 84% of all patients. During follow-up, in about 50% of patients, all of them C3NeF-positive, C3 levels remained low. Linear mixed model analysis showed that C3GN patients had higher soluble C5b-9 (sC5b-9) and lower properdin levels compared to DDD patients. With a median follow-up of 52 months, an overall benign outcome was observed with only six patients with eGFR below 90 ml/min/1.73 m2 at last follow-up. Conclusions We extensively described clinical and laboratory findings including complement features of an exclusively pediatric C3G cohort. Outcome was relatively benign, persistent low C3 correlated with C3NeF presence, and C3GN was associated with higher sC5b-9 and lower properdin levels. Prospective studies are needed to further elucidate the pathogenic mechanisms underlying C3G and guide personalized medicine with complement therapeutics. Graphical abstract

scholarly journals 103 Periodontal Health and Sarcopenia: Cross-Sectional Evidence From A Cohort of 2040 Twin Volunteers

2021 ◽  
Vol 50 (Supplement_1) ◽  
pp. i12-i42
Author(s):  
M B Zazzara ◽  
P M Wells ◽  
R C E Bowyer ◽  
M N Lochlainn ◽  
E J Thompson ◽  
...  
Keyword(s):  
Mixed Model ◽  
Linear Mixed Model ◽  
Frailty Index ◽  
Muscle Quality ◽  
Low Grade ◽  
Periodontal Health ◽  
Cross Sectional ◽  
Age Related ◽  
European Working ◽  
Generalised Linear Mixed Model

Abstract Introduction Periodontitis is a chronic inflammatory disease affecting the periodontium, ultimately leading to looseness and/or loss of teeth. Sarcopenia refers to age-related reduction in muscle mass and strength. Similar to periodontitis, chronic low-grade inflammation is thought to play a key role in its development. In addition, both increase in prevalence with advancing age. Despite known associations with other diseases involving a dysregulated inflammatory response, for example rheumatoid arthritis,, the relationship between periodontitis and sarcopenia, and whether they could be driven by similar processes, remains uncertain. The aim of this study was to explore the association between periodontitis and sarcopenia. Methods Observational study of 2040 adult volunteers [age 67.18 (12.17)] enrolled in the TwinsUK cohort study. Presence of tooth mobility and number of teeth lost were used to assess periodontal health. A binary variable was created to define periodontitis. Measurements of muscle strength, muscle quality/quantity and physical performance were used to assess sarcopenia. A categorical variable was created according to the European Working Group on Sarcopenia in Older People (EWGSOP2) consensus, to define sarcopenia (1: probable; 2: positive; 3: severe). Generalised linear mixed model analysis used on complete cases and age-matched (n = 1,288) samples to ascertain associations between periodontitis and sarcopenia. Results No significant association was found between periodontitis and sarcopenia in both the complete cases analysis and age-matched analysis. Results were consistent when analysis was adjusted for potential confounders including body mass index, frailty index, Mini Mental State Examination smoking, nutritional status and educational level. Conclusions This study found no significant association between periodontitis and sarcopenia in a cohort of 2040 adults. Although both periodontitis and sarcopenia have been linked to a dysregulated immune response and demonstrate an increase in prevalence with increasing age, our work is inconclusive due to the plethora of possible aetiopathogenetic pathways.

Identifying patients with CKD risk at the time of nephrectomy: When to initiate nephrology consult

2021 ◽  
pp. 239936932110319
Author(s):  
Yihe Yang ◽  
Zachary Kozel ◽  
Purva Sharma ◽  
Oksana Yaskiv ◽  
Jose Torres ◽  
...  
Keyword(s):  
Risk Factors ◽  
Multivariate Analysis ◽  
Radical Nephrectomy ◽  
Mixed Model ◽  
Linear Mixed Model ◽  
Interstitial Fibrosis ◽  
Kidney Neoplasm ◽  
Tubular Atrophy ◽  
Independent Risk Factors

Introduction: The prevalence of chronic kidney disease (CKD) is high among kidney neoplasm patients because of the overlapping risk factors. Our purpose is to identify kidney cancer survivors with higher CKD risk. Methods: We studied a retrospective cohort of 361 kidney tumor patients with partial or radical nephrectomy. Linear mixed model was performed. Results: Of patients with follow-up >3 months, 84% were identified retrospectively to fulfill criteria for CKD diagnosis, although CKD was documented in only 15%. Urinalysis was performed in 205 (57%) patients at the time of nephrectomy. Multivariate analysis showed interstitial fibrosis and tubular atrophy (IFTA) >25% ( p = 0.005), severe arteriolar sclerosis ( p = 0.013), female gender ( p = 0.024), older age ( p = 0.012), BMI ⩾ 25 kg/m2 ( p < 0.001), documented CKD ( p < 0.001), baseline eGFR ⩽ 60 ml/min/1.73 m2 ( p < 0.001), and radical nephrectomy ( p < 0.001) were independent risk factors of lower eGFR at baseline and during follow-up. Average eGFR decreased within 3 months post nephrectomy. However, patients with different risk levels showed different eGFR time trend pattern at longer follow-ups. Multivariate analysis of time × risk factor interaction showed BMI, radical nephrectomy and baseline eGFR had time-dependent impact. BMI ⩾ 25 kg/m2 and radical nephrectomy were associated with steeper eGFR decrease slope. In baseline eGFR > 90 ml/min/1.73 m2 group, eGFR rebounded to pre-nephrectomy levels during extended follow-up. In partial nephrectomy patients with baseline eGFR ⩾ 90 ml/min/1.73 m2 ( n = 61), proteinuria ( p < 0.001) and BMI ( p < 0.001) were independent risk factors of decreased eGFR during follow up. Conclusions: As have been suggested by others and confirmed by our study, proteinuria and CKD are greatly under-recognized. Although self-evident as a minimum workup for nephrectomy patients to include SCr, eGFR, urinalysis, and proteinuria, the need for uniform applications of this practice should be reinforced. Non-neoplastic histology evaluation is valuable and should include an estimate of global sclerosis% (GS) and IFTA%. Patients with any proteinuria and/or eGFR ⩽ 60 at the time of nephrectomy or in follow-up with urologists, and/or >25% GS or IFTA, should be referred for early nephrology consultation.

Tu1548 Metallic Stent Deployment in Endosonography-Guided Biliary Drainage: Long Term Follow-up Results in Patients With Bilio-Enteric Anastomosis

2012 ◽  
Vol 75 (4) ◽  
pp. AB443
Author(s):  
Jun Horaguchi ◽  
Naotaka Fujita ◽  
Yutaka Noda ◽  
Go Kobayashi ◽  
Kei Ito ◽  
...  
Keyword(s):  
Biliary Drainage ◽  
Metallic Stent ◽  
Stent Deployment ◽  
Long Term Follow Up

Factors influencing the occurrence of high ultimate pH in three muscles of lamb carcasses in Australia

2014 ◽  
Vol 54 (10) ◽  
pp. 1853 ◽  
Author(s):  
N. G. McPhail ◽  
J. L. Stark ◽  
A. J. Ball ◽  
R. D. Warner
Keyword(s):  
Mixed Model ◽  
Linear Mixed Model ◽  
Rectus Femoris ◽  
Carcass Weight ◽  
Mixed Model Analysis ◽  
Factors Influencing ◽  
South Wales ◽  
Generalised Linear Mixed Model ◽  
Processing Plants ◽  
Few Data

Chilled lamb meat exported from Australia has, on occasions, been rejected by importing countries due to greening, after only 6 weeks of storage time. Greening is known to be more prevalent in high ultimate pH (pHu) beef meat (>5.9). There are few data available for lamb carcasses in Australia on the occurrence of high pHu meat, which may have an impact on the understanding and control of quality and greening during storage. The aim of this project was to determine the prevalence of, and influencing factors for, high pHu meat in a range of muscle types in lamb carcasses in Australia. Muscle pHu data were collected from a total of 1614 carcasses from 78 lots at four lamb processing plants in Victoria and New South Wales in autumn and spring of 2013. The pHu of the knuckle (rectus femoris), rack (longissimus) and blade (infraspinatus) was measured and data on carcass and lot characteristics were recorded. Data were subjected to restricted maximum likelihood and generalised linear mixed model analysis. The mean pHu of the knuckle, rack and shoulder were 6.06, 5.79 and 6.12 respectively, and the main factors influencing muscle pHu and occurrence of dark-cutting were breed, season, electrical stimulation and carcass weight. Merino lambs had a higher pHu in the blade and knuckle than did other breeds (P < 0.05, P < 0.01 respectively). Lambs processed in autumn had a higher predicted pHu in the blade and knuckle and a higher percentage dark-cutting (DC; pHu >6.0) for those muscles, than did those processed in spring (P < 0.05). Carcasses that had been electrically stimulated had a higher %DC and a higher pHu in all three muscles (P < 0.05). Carcass weight had a significant effect on the pHu of all three muscles (P < 0.001), with heavier carcasses having a lower pHu and lower %DC. The pHu of the rack was not a reliable predictor for the pHu in other muscles of the lamb carcass. In conclusion, the high occurrence of DC in the muscles, particularly the blade and knuckle, suggests that these muscles may be at risk for producing greening in the vacuum bag during storage.

Sign in / Sign up

Export Citation Format

Share Document