Skeletal Measurements Research Articles

Measuring and monitoring skeletal muscle function in COPD: current perspectives.

Skeletal muscle dysfunction is an important systemic consequence of chronic obstructive pulmonary disease (COPD) that worsens the natural cause of the disease. Up to a third of all people with COPD express some form of impairment which encompasses reductions in strength and endurance, as well as an increased fatigability. Considering this complexity, no single test could be used to measure and monitor all aspects of the impaired skeletal muscle function within the COPD population, resulting in a wide range of available tests and measurement techniques. The aim of the current review is to highlight current and new perspectives relevant to skeletal muscle function measurements within the COPD population in order to provide guidance for researchers as well as for clinicians. First of all, standardized and clinically feasible measurement protocols, as well as normative values and predictive equations across the spectrum of impaired function in COPD, are needed before assessment of skeletal muscle function can become a reality in clinical praxis. This should minimally target the quadriceps muscle; however, depending on the objective of measurements, eg, to determine upper limb muscle function or walking capacity, other muscles could also be tested. Furthermore, even though muscle strength measurements are important, current evidence suggests that other aspects, such as the endurance and power capacity of the muscle, should also be considered. Moreover, although static (isometric) measurements have been favored, dynamic measurements of skeletal muscle function should not be neglected as they, in a larger extent than static measurements, are related to tasks of daily living. Lastly, the often modest relationships between functional tests and skeletal muscle function measurements indicate that they evaluate different constructs and thus cannot replace one another. Therefore, for accurate measurements of skeletal muscle function in people with COPD, specific and formal measurements should still be prioritized.

A simple skeletal measurement effectively predicts climbing behaviour in a diverse clade of small mammals

AbstractArboreal locomotion allows access to above-ground resources and might have fostered the diversification of mammals. Nevertheless, simple morphological measurements that consistently correlate with arboreality remain indefinable. As such, the climbing habits of many species of mammals, living and extinct, remain speculative. We collected quantitative data on the climbing tendencies of 20 species of murine rodents, an ecologically and morphologically diverse clade. We leveraged Bayesian phylogenetic mixed models (BPMMs), incorporating intraspecific variation and phylogenetic uncertainty, to determine which, if any, traits (17 skeletal indices) predict climbing frequency. We used ordinal BPMMs to test the ability of the indices to place 48 murine species that lack quantitative climbing data into three qualitative locomotor categories (terrestrial, general and arboreal). Only two indices (both measures of relative digit length) accurately predict locomotor styles, with manus digit length showing the best fit. Manus digit length has low phylogenetic signal, is largely explained by locomotor ecology and might effectively predict locomotion across a multitude of small mammals, including extinct species. Surprisingly, relative tail length, a common proxy for locomotion, was a poor predictor of climbing. In general, detailed, quantitative natural history data, such as those presented here, are needed to enhance our understanding of the evolutionary and ecological success of clades.

Rapid maxillary expansion outcomes according to midpalatal suture maturation levels

BackgroundThis study aims to compare the relationship between skeletal and dental outcomes of rapid maxillary expansion (RME) treatment on cone beam computed tomography (CBCT) images between pre-pubertal peak (pre-peak) and post-pubertal peak (post-peak) patients. The null hypothesis was that there was no difference in the outcomes of RME treatment between the groups.MethodsThirty-two patients who underwent RME treatment were classified according to midpalatal suture maturation levels and then divided into two groups as pre-peak and post-peak. Skeletal and dental measurements were performed on the CBCT images at T0 (pre-treatment stage) and at T1 (post-treatment stage). Paired sample t test was used to evaluate normally distributed data and P < 0.05 was taken as the significance level.ResultsThere were significant differences between T0 and T1 within the groups, but the changes between the pre-peak and post-peak patient groups were not statistically significant.ConclusionNon-significant changes were found between the two groups, and the null hypothesis was excepted.

Two Insertion/Deletion Variants within SPAG17 Gene Are Associated with Goat Body Measurement Traits.

Simple SummarySperm-associated antigen 17 (SPAG17) is a reproduction and skeletal development related gene. This study aimed to identify crucial insertion-deletion (indel) variations, which influence the body measurement traits of goats. Two intronic indels (14 bp and 17 bp indels) were identified by sequencing. In Shaanbei white cashmere goat (SBWC), the different genotypes of the 14 bp indel were markedly associated with goat body height, chest width, body length, and chest depth. The genotypes of the 17 bp indel were significantly associated with body height and chest width. The different combined genotypes were significantly associated with body height and chest width of SBWC and ten traits of Hainan black goat. These results suggested that the 14 and 17 bp indels within SPAG17 can be used in goat growth related traits marker-assisted selection breeding, especially body height. Sperm-associated antigen 17 (SPAG17) gene encodes a multifunctional cytoplasmic protein, which influences not only reproduction but also skeletal development related body measurement traits, especially body height. Thus, this study aimed to identify crucial insertion-deletion (indel) variations, which influence the body measurement traits of goats in large goat populations (n = 1725). As a result, two intronic indels (14 bp and 17 bp indel) were identified by sequencing. For the two indel loci, the distributions of genotypes and alleles were significantly different between the Shaanbei white cashmere goat (SBWC) and the Hainan black goat (HNBG). In SBWC goats, the different genotypes of the 14 bp indel were markedly associated with goat body height, chest width, body length and chest depth. The genotypes of the 17 bp indel were significantly related to body height and chest width. At the two loci, for all seven analyzed traits of SBWC goat, the growth data of DD homozygotes were the worst, which means that the 14 bp insertion and the 17 bp deletion were beneficial and detrimental variations, respectively. Moreover, the combined genotypes were significantly related to body height and chest width of SBWC goats and ten traits of HNBG. These results suggested that the 14 and 17 bp indels within SPAG17 can be used in goat growth related traits marker-assisted selection breeding, especially body height.

Effect of feeding heat-treated and unheated colostrum on immunoglobulin G absorption, health and performance of neonatal Holstein dairy calves

First colostrum is an important source of nutrients and immune factors which are necessary for calves in the first weeks of life. Despite these benefits, colostrum can also represent one of the earliest potential exposures of dairy calves to infectious agents which these patogens can act directly on growth and cause diseases such as scours or septicemia. With recent increased interest in pasteurized milk feeding systems, producers have been curious to learn if there may also be benefits from feeding pasteurized colostrum. This study was realized to determine the effects of feeding heat-treated colostrum or unheated colostrum on passive transfer of immunity, immunoglobulin G (IgG) concentration, total plate count, health and performance of neonatal dairy calves. First-milking colostrum was collected from Holstein cows and frozen at -20°C to accumulate a large batch. Pooled batches of colostrum were mixed and divided equally: One half was fed unheated colostrum; whereas the other half was fed after heat treatment at 60°C for 30 min. Forty newborn male Holstein dairy calves were fed either unheated (n = 20) and heat-treated colostrum (n = 20), 10% of their birth weight. Calves received 4 L within 1 to 2h after birth and residuals was fed 6h after birth. Serum samples collected from calves and were assayed for serum total protein (STP) and IgG. Feed intake recorded weekly and body weight and skeletal growth measures recorded at d 3 and d 63 (weaning). Every day, calves clinically diagnosed either as being healthy or suffering from respiratory disease and neonatal calf diarrhea. Heat-treated colostrum resulted in lower colostrum bacterial concentration (2.01 vs. 3.96 cfu mL-1). Calves fed heat treated colostrum had greater STP in 24, 72h and 23d, IgG concentrations at 24 and 72h plus unheated colostrum. Also weaning weight and average daily gain were greater in calves feed heated colostrum. There were no differences in starter intake and feed efficiency between two groups. Calves fed heat-treated colostrum had lower fecal scores, diarrhea and pneumonia incidence. There were not differences in skeletal growth measurements except body barrel. These results shows that feeding heated colostrum can provide better growth and health in neonatal calves.

Differences in craniofacial growth of Class II individuals from different decades: A retrospective study.

To detect changes in mandibular growth between a historical group (HG) from the American Association of Orthodontics Foundation Craniofacial Growth Legacy Collection (AAOF Legacy) and a contemporary group (CG) of normodivergent or hypodivergent Class II untreated subjects. The sample included radiographs from the AAOF Legacy and from the University of Naples 'Federico II'collected during a previous RCT. The HG was composed of 26 individuals (around 1960) from the AAOF Legacy (15 from the Burlington Growth Study, nine from the Oregon Growth Study and two from the Michigan Growth Study) who were matched by sex, age and race with the 26 individuals of the CG (around 2010). Two lateral cephalograms obtained at T0 and T1 (12months) were selected, and one examiner performed the cephalometric measurements according to Pancherz's method. The normal distribution of data was confirmed by the Shapiro-Wilk test, MANOVA analysis and t test for paired and unpaired data were performed. The level of significance was set according to Bonferroni's correction. At T0 and T1, the between-group comparisons revealed greater linear dimensions for Maxillary base, Maxillary incisor and Mandibular incisor in the CG than in the HG (P≤0.002). No significant difference was found in the growth rate for linear skeletal measurement between the HG and the CG. In this study, the cephalometric analysis showed larger maxillarydimensions for the CG than the HG, while no differences were shown between the growth rate and direction of the two groups.

Redefining Physiologic Predictors of Endurance Performance with Measures of Skeletal Muscle Oxygenation: E pluribus unum

PURPOSE: To scrutinize the ability of classic measures of endurance performance vs. NIRS-derived measures of skeletal muscle oxygenation to predict 25 km cycling time trial performance. METHODS: 14 participants (4 f / 10 m) underwent 3 sequential exercise bouts on a cycle ergometer while fitted with NIRS devices over each vastus lateralis: 1) A warmup consisting of 2 sequential 7.5-min bouts of 50 and 100 W at 80 rpm to determine gross efficiency (GE), exercise economy (EC), and delta efficiency (DE) across the same absolute workloads followed by an incremental max test to volitional fatigue (VF) used to discern 3 separate measures of ventilatory threshold (VT), maximal rates of whole-body oxygen consumption (VO2max) and maximal aerobic power (Wmax); 2) A warmup consisting of 2 sequential 7.5-min bouts at 80 rpm corresponding to 15% and 30% Wmax for GE, EC, and DE across the same relative workloads followed by a 60 sec ramp to a sustained 110% Wmax until VF to verify VO2max; and 3) A 25 km TT. Ventilatory measures were sampled throughout bouts 1 and 2. RESULTS: Stepwise and multiple linear regression analyses revealed that from the classic variables only mean VTVO2 (2.59 ± 0.53 l O2·min-1, p = 0.019) and EC at 15% Wmax (47 ± 10 W, p = 0.030) explained (adj R2 = 0.463; p = 0.013) 25 km TT performance (46:40 ± 04:36 min:sec) variance whereas the change in skeletal muscle oxygenation (ΔSmO2; -6.9 ± 6.1%; p = 0.001) from 50 to 100 W and the deoxygenated hemoglobin and myoglobin index (HHb) at Wmax (9.57 ± 1.56; p = 0.044) were the best NIRS-derived variables to describe TT performance (adj R2 = 0.751; p < 0.001). When combining all variables, skeletal muscle measures provided a superior physiologic explanation of 25 km TT performance versus those classically used to describe endurance performance (VTVO2, EC @ 15% Wmax, HHbmax, and ΔSmO2 at p = 0.083, 0.056, 0.008, and 0.005, respectively). CONCLUSION: These results demonstrate that measures reflecting the balance of skeletal muscle O2 delivery and utilization during exercise are superior to classic measures of whole-body aerobic capacity, ventilatory threshold, and/or the efficiency of exercise at predicting 25 km time trial (TT) cycling performance.

Cephalometric features of Angle class III malocclusion with different dentoalveolar compensation (retrospective study)

Introduction: This study was to investigate dentoalveolar compensation in untreated skeletal Class III patients. Methods:This retrospective study was conducted on 102 untreated Class III malocclusion patients. They were divided into group 1 (overjet<0mm, n=51) and group 2 (overjet ≥ 0mm, n=51). Twenty-six cephlometric readings were compared between the two groups. Correlation analysis was performed between the overjet with skeletal and dental measurements and Regression analysis was performed to determine the overjet. Results: The results showed a significantly higher SNB, S-N-Pg, gonial angle and L1-NB mm in the negative overjet group. While, the ANB angle, angle of convexity, Wits appraisal, bony chin and U1- A-Pg mm were significantly higher in the positive overjet group. However, no statistically significant difference was found in the rest of the readings. Correlational analyses showed that the overjet has significant negative correlation with SNB, S-N-Pg, L1-Frankfort, gonialangles. On the other hand, it had significant positivecorrelation with ANB angle, angle of convexity, Wits appraisal, bony chin, L1-MP angle and U1-A-Pg mm. Nine regression equations for the overjet were calculated with the highest coeffcient of determination of 0.33. Conclusion: Dentoalveolar compensation was seen in Class III cases with less skeletal discrepancy, lower mandibular prominence, larger bony chin, greater angle of convexity and smaller gonial angle. Moreover, the position of the maxillary and mandibular incisors on the basal bone, rather than their inclination, contributed in dentoalveolar compensation

Computed Tomography-Determined Muscle Quality Rather Than Muscle Quantity Is a Better Determinant of Prolonged Hospital Length of Stay in Patients Undergoing Transcatheter Aortic Valve Implantation

Computed tomography (CT)-determined skeletal muscle measures have been used for predicting postoperative outcomes in patients undergoing transcatheter aortic valve implantation (TAVI). We investigated the impact of CT-determined muscle quantity (measured as psoas muscle area [PMA] and psoas muscle index [PMI]) and quality (measured as psoas muscle density [PMD]) on hospital length of stay (LOS) after TAVI. We retrospectively identified 182 consecutive patients who underwent TAVI between March 2013 and August 2017 with adequate preprocedural CT imaging. Baseline demographic and clinical data, the Society of Thoracic Surgeons score, the essential frailty toolset (EFT) frailty rating, and precontrast PMD, PMA, and PMI were obtained in all study patients. The primary outcome was prolonged postoperative LOS defined as greater than 14 days. Patients with prolonged LOS had a significantly higher Society of Thoracic Surgeons score (p < 0.001) and significantly lower PMD (p < 0.001) than those with LOS ≤14 days. More patients with prolonged LOS had concomitant peripheral vascular disease (p = 0.001), had undergone percutaneous coronary interventions (p = 0.022), and had an EFT score ≥4 (p < 0.001) compared to those without prolonged LOS. Neither PMA (p = 0.123) nor PMI (p = 0.271) were associated with prolonged LOS. Multivariate analysis identified EFT score ≥4, the presence of peripheral vascular disease, and PMD as independent predictors of prolonged LOS. The precontrast CT-determined muscle quality measurement PMD is a simple and objective predictor of prolonged LOS after TAVI.

A unified-models analysis of the development of sexual size dimorphism in Damaraland mole-rats, Fukomys damarensis

AbstractIndividual variation in growth rates often generates variation in fitness. However, the ability to draw meaningful inferences from growth data depends on the use of growth models that allow for direct comparisons of growth between the sexes, between populations, and between species. Unlike traditional sigmoid functions, a recently parameterized family of unified growth models provides a reliable basis for comparisons since each parameter affects a single curve characteristic and parameters are directly comparable across the unified family. Here, we use the unified-models approach to examine the development of sexual size dimorphism in Damaraland mole-rats (Fukomys damarensis), where breeding males are larger than breeding females. Using skeletal measurements, we show here that the larger size of male Damaraland mole-rats arises from an increased growth rate across the entire period of development, rather than through sex differences in the duration or timing of growth. Male-biased skeletal size dimorphism is not unusual among rodents, and our measures of sex differences in size in captive mole-rats are close to sexual size differences in the wild, where size dimorphism = 1.04 (male:female). We hope our study will encourage the wide use of unified growth models by mammalogists.

Simultaneous R2, R2' and R2* measurement of skeletal muscle in a rabbit model of unilateral artery embolization

PurposeTo demonstrate the feasibility of using a susceptibility-based MRI technique with multi-echo gradient and spin echo (MEGSE) sequence to achieve simultaneous R2, R2' and R2* measurement and assess skeletal muscle oxygenation alternations in a rabbit model of unilateral artery embolization. Materials and MethodsApproved by the local institutional review board for experimental animal studies, nine New Zealand White rabbits were included in this study. The MEGSE sequence consists of embedding a set of gradient echoes around the echo of a single spin-echo sequence using several gradient echoes to collect the magnetization intensity during the formation and attenuation of spin-echo simultaneously after 180° radio frequency pulse. Within-session and between-day tests were conducted to evaluate the reproducibility of this skeletal muscle oxygenation alternations measurement. Furthermore, all the MEGSE scans of skeletal muscle were conducted using a 3-T clinical MRI scanner during resting state (before unilateral artery embolization operation, pre), 1 h after unilateral artery embolization operation (post1) and 2 h after unilateral artery embolization operation (post2) model to verify the feasibility and sensitivity of this method. ResultsThe within-session coefficient of variations (CVs) of R2, R2' and R2* measurements were 1.57%, 3.33% and 2.57%, while the between-day CVs of were 1.42%, 5.85% and 2.85%. In all rabbits, the mean R2 decreased significantly from 36.46 ± 1.03 s−1 (pre) to 30.58 ± 2.11 s−1 (post1,**P < 0.01, relative to pre) and 28.62 ± 1.53 s−1 (post2, **P < 0.01, relative to post1), and the mean R2' went up markedly from 9.88 ± 2.14 s−1 (pre) to 16.10 ± 2.74 s−1 (post1, **P < 0.01) and 17.33 ± 2.25 s−1 (post2, **P < 0.05). The mean R2* increased from 43.27 ± 3.75 s−1 (pre) to 47.90 ± 5.08 s−1 (post1, *P < 0.05) and to 48.04 ± 4.42 s−1 (post2, NS, P > 0.05). ConclusionThis study demonstrates the feasibility of simultaneous R2, R2' and R2* measurement method for the evaluation of skeletal muscle ischemia. Besides, this study indicates the sensitivity of the R2 and R2' compared with R2* and especially the necessity of R2 and R2' measurement for the further evaluation of skeletal muscle ischemia which always causes both edema and hypoxia in a rabbit model of unilateral artery embolization.

The Use of Roche, Wainer, and Thissen's Skeletal Maturity of the Knee.

The Roche, Wainer, and Thissen (RWT) knee method was designed to assess maturity in living individuals, but is infrequently cited in studies of skeletal measures for legal age thresholds or estimation of age-at-death for forensic cases. We implement the RWT method using R scripts and analyze its utility in establishing an age threshold of 18years. We fit the RWT model and verify its accuracy in estimating skeletal age against results and known age data provided by RWT. We also found the transition distribution for full skeletal maturity. Agreement between the RWT method and our implementation was good, with a maximum deviation of 0.03years. The modes of transition to full skeletal maturity are 18.37 and 17.16years for males and females. The corresponding Bayes factors are 5.73 and 1.77, indicating that complete skeletal maturity of the knee does not provide conclusive evidence of attainment of 18years of age.

Transverse Malocclusion and Temporomandibular Disorders: Verification of the Controversy.

To investigate the transverse dental and skeletal aspects of malocclusion in a sample of temporomandibular disorders (TMD) patients and to assess the correlations of these aspects with the signs and symptoms of TMD. A total of 150 TMD patients diagnosed according to the Diagnostic Criteria for TMD were divided into five groups: Group 1 (myalgia), Group 2 (disc displacement with reduction [DDWR]), Group 3 (disc displacement without reduction [DDWOR]), Group 4 (degenerative disorders), and Group 5 (subluxation). The transverse occlusion was assessed clinically, and any posterior crossbite present was recorded. Using cone beam computed tomography, several skeletal and dental transverse measurements were evaluated in each patient to diagnose the presence of skeletal posterior crossbite and possible facial and dental asymmetry. One-way analysis of variance was used to compare the means of more than two groups. Pearson correlation coefficient was used to assess the correlations of quantitative continuous variables. Significance level was considered at P < .05. Posterior crossbite was found in only 18% of the sample, while 28.7% of the subjects showed transverse skeletal crossbite. All skeletal and dental measurements evaluating symmetry showed no statistically significant differences between the groups except for the occlusal plane cant, which was significantly higher in Group 2 compared to Group 1. Dental and skeletal transverse discrepancies showed no correlation with TMD. Transverse malocclusion is not correlated with the signs and symptoms of TMD.

Lateral cephalometric measurements of Iranians with surgically repaired unilateral cleft lips and palates

Since results of surgical correction of unilateral cleft lip and palate (UCLP) are controversial, and there is no study in this regard among Iranians, this study was conducted to document lateral cephalometric measurements of such cases, with respect to age, gender, and cleft side. In this cross-sectional study, 45 lateral cephalographs of individuals with UCLP who had undergone surgery but not orthodontic treatment were traced and 30 skeletal, dental and soft-tissue cephalometric measurements were measured. Parameters were compared between patients with UCLP and cephalometric norms. They were also compared between males and females, two age groups (≤8 and>8 years), and sides of cleft using the Student's t-test. Only S-N-Pog and U1-SN values were significantly different between this sample and cephalometric norms. The variables were not significantly different between males and females. However, the values of ANB, Wits appraisal, Go-Gn, Go-Pog, U1-SN, interincisal angle, distance of upper lip to Ricketts E-line, and nasopharyngeal depth were significantly different between patients≤8 and>8 years (P<0.05). The S-N-Pog angle, Wits appraisal, Go-Gn, Go-Pog, U1-SN, interincisal angle and hypopharyngeal depth were significantly different between patients with right- and left-side clefts (P<0.05). Measurements of patients with repaired UCLP were similar to cephalometric norms except for two parameters.

Muscle Mass, Density, and Strength Are Necessary to Diagnose Sarcopenia in Patients With Gastric Cancer

BackgroundAccurate evaluation of muscle strength and function is difficult. Commonly known as sarcopenia, skeletal muscle loss is closely correlated with the prognosis of patients diagnosed with gastric cancer (GC). We wondered the correlation between skeletal muscle measures combined with computed tomography and grip strength (GS) and short-term outcomes after radical gastrectomy (RG) in patients with GC. Materials and methodsWe analyzed 594 patients with GC who underwent RG. The skeletal muscle index (SMI), skeletal muscle density (Hounsfield unit average calculation [HUAC]), and GS were measured. The skeletal muscle gauge (SMG) was created by multiplying SMI and HUAC. Logistic regression modeling and multivariate analysis were used. ResultsUnivariate analysis showed that low SMI, low HUAC, low GS, and low SMG were predictors of short-term complications after surgery. Compared with other muscle-related factors (AUCHUAC = 0.559, AUCSMI = 0.575, AUCGS = 0.580, AUCSMG = 0.598, AUCSMI+GS = 0.559), low GS plus SMG (AUCGS plus SMG = 0.614, P < 0.01) was a more accurate independent risk factor for postoperative complications. Moreover, the risk model with SMG plus GS for the diagnosis of skeletal muscle loss was superior to the other models (c-index = 0.729). ConclusionsSkeletal muscle measures using computed tomography and GS are closely correlated with short-term outcomes of patients diagnosed with GC after RG. The model contained SMG plus GS could effectively predict for patients with GC after RG at high risk of short-term outcomes. SMG plus GS has the highest accuracy for the several evaluation methods of sarcopenia.

Allele length of the DMPK CTG repeat is a predictor of progressive myotonic dystrophy type 1 phenotypes.

Myotonic dystrophy type 1 (DM1) is an autosomal dominant inherited disorder caused by expansion of a germline and somatically unstable CTG repeat in the DMPK gene. Previously, CTG repeat length at birth has been correlated to patient age at symptom onset. Attempts to correlate CTG repeat length with progressive DM1 phenotypes, such as muscle power, have proven difficult. To better correlate genotype with progressive phenotypes, we have measured CTG repeat tract length and screened for interrupting variant repeats in 192 study participants from a well-characterized Canadian cohort. We have assessed genotype-phenotype correlations with nine progressive measures of skeletal muscle power and respiratory function. We have built statistical models that include confounding factors such as sex, age, height and weight to further explain variation in muscle power. Our analysis reveals a strong correlation between DM1 genotype and respiratory function and skeletal muscle power, as part of a complex model that includes additional modulators such as sex, age, height, weight and the presence or absence of interrupting variant repeats. Distal skeletal muscle measurements, such as hand pinch and grip strength, show the strongest correlation with disease genotype. Detailed analysis of CTG repeat length, and incorporation of confounding factors, greatly improves the predictive ability of these models. They reveal a greater genetic influence on individual progressive phenotypes than on age at symptom onset and for clinical trials will help optimize stratification and explain patient variability. They will also help practitioners prioritize assessment of the muscular power measurements that correlate best with disease severity.

A Novel Model Incorporating Pectoralis Muscle Measures to Predict Mortality after Ventricular Assist Device Implantation

Purpose We have previously shown that pectoralis muscle mass and tissue attenuation obtained on preoperative CT scans were powerful predictors of mortality after LVAD implantation using single center data. This analysis confirms those findings in a separate LVAD dataset and presents a novel prediction model developed across centers. Methods Patients with chest CTs performed ≤ 3 months before LVAD implantation at University of Minnesota (n=143) and Houston Methodist Hospital (n=133) were identified from larger cohorts (University of Minnesota n=353, Houston Methodist =278). Unilateral pectoralis muscle mass indexed to body surface area (PMI) and attenuation (approximated by mean Hounsfield units; PHUm) were measured on preoperative chest CT scans. To develop the Pectoralis Muscle Risk Score (PMRS), we implemented a cross-validated model selection using Cox's proportional hazards regression model with censoring at transplantation. The final model included PHUm, sex, albumin, year of implant, body mass index, bridge to transplant, INTERMACS profile, and presence or absence of contrast. Receiver-operating characteristic (ROC) curves for 30, 90, and 365 day survival were generated for the model and compared to the HeartMate II Risk Score (HMRS). Results The Pectoralis Risk Score outperformed HMRS at each of the pre-specified time-points. The AUC for PMRS for predicting survival at 30, 90, and 365 days was 78%, 76%, and 76%, respectively. The HMRS had AUC of 63%, 67%, and 63% (Figure). Conclusion The Pectoralis Muscle Risk Score had favorable discrimination in this multicenter dataset. These skeletal muscle measures, which are associated with heart failure stage and frailty, appear to add important information to pre-operative risk assessment.

Severity and Outcome Assessment score: a useful tool for auditing orthognathic surgery

Many indices and scoring systems exist for assessing skeletal patterns and malocclusion but none have been universally adopted by teams providing orthognathic surgery in the UK. Using a standardised objective measure of a patient’s condition is important both for service provision, treatment allocation, and other clinical governance domains. The Severity and Outcome Assessment tool (SOA) developed by the British Orthodontic Society (BOS) and British Association of Oral and Maxillofacial Surgeons (BAOMS) provides a standardised method of assessing patients throughout the orthognathic pathway and lends itself to case selection, resource allocation and auditing treatment outcomes. The SOA uses 7 cephalometric skeletal, dental and soft tissue measures to produce an overall score.The SOA has been used by the current NHS Tayside orthognathic team since August 2006 to audit treatment outcomes. While we recognise that cephalometric analysis forms only one part of orthognathic treatment we believe that having an objective measure on which to assess treatment is useful. We present our experience of using this quick, simple and reproducible tool in auditing orthognathic treatment outcomes.

Creatine supplementation in Walker-256 tumor-bearing rats prevents skeletal muscle atrophy by attenuating systemic inflammation and protein degradation signaling.

The aim of this study was to investigate the effects of creatine supplementation on muscle wasting in Walker-256 tumor-bearing rats. Wistar rats were randomly assigned into three groups (n = 10/group): control (C), tumor bearing (T), and tumor bearing supplemented with creatine (TCr). Creatine was provided in drinking water for a total of 21days. After 11days of supplementation, tumor cells were implanted subcutaneously into T and TCr groups. The animals' weight, food and water intake were evaluated along the experimental protocol. After 10days of tumor implantation (21 total), animals were euthanized for inflammatory state and skeletal muscle cross-sectional area measurements. Skeletal muscle components of ubiquitin-proteasome pathways were also evaluated using real-time PCR and immunoblotting. The results showed that creatine supplementation protected tumor-bearing rats against body weight loss and skeletal muscle atrophy. Creatine intake promoted lower levels of plasma TNF-α and IL-6 and smaller spleen morphology changes such as reduced size of white pulp and lymphoid follicle compared to tumor-bearing rats. In addition, creatine prevented increased levels of skeletal muscle Atrogin-1 and MuRF-1, key regulators of muscle atrophy. Creatine supplementation prevents skeletal muscle atrophy by attenuating tumor-induced pro-inflammatory environment, a condition that minimizes Atrogin-1 and MuRF-1-dependent proteolysis.

Standard methods for creating digital skeletal models using structure-from-motion photogrammetry.

This article assesses best practices for producing 3D digital cranial models through structure-from-motion (SfM) photogrammetry, and whether the metric accuracy and overall presentation of photogrammetric models are comparable to physical crania. It is intended to present a user-friendly standard method of creating accurate digital skeletal models using Agisoft PhotoScan. Approximately 200 photographs were taken of three different crania, and were separated into series consisting of 50, 75, 100, 150, and approximately 200 photos. Forty-five cranial models were created using different photo series and a variety of PhotoScan settings. These models were assessed based on defined qualitative criteria, and model measurement estimates were compared with physical skeletal measurements using Bland-Altman plots. The majority of all models (37/45) produced measurement estimates with mean differences of 2 mm or less regardless of PhotoScan settings, and therefore demonstrated high levels of agreement with the physical measurements. Models created with 150 photographs and on "high" PhotoScan settings scored the highest in terms of qualitative appearance in the shortest amount of time. In PhotoScan, it is recommended to create cranial models using 150 photographs and "high" settings; this produces digital cranial models that are comparable to physical crania in both appearance and proportion. SfM photogrammetry is a convenient, noninvasive, and rapid 3D modeling tool that can be used in almost any setting to produce digital models, and following the guidelines established here will ensure that these models are metrically accurate.