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Pectoral Muscles (pectoral + muscle)
Terms modified by Pectoral Muscles Selected AbstractsThe use of muscle protein for egg production in the Zebra Finch Taeniopygia guttataIBIS, Issue 2 2002Mat Cottam Pectoral muscle can be an important source of protein for birds. During egg formation Zebra Finches Taeniopygia guttata are able to compensate for nutritional inadequacies in their diet by utilization of the protein in their flight muscles. This analysis of flight muscle sarcoplasm supported earlier observations of protein depletion during egg production. However, SDS gel electrophoresis of the sarcoplasm produced no evidence to support a previous suggestion of the existence of a high molecular weight storage protein, and it is thought that the original observation may have arisen as an artefact of experimental methodology. During laying, protein removal from the sarcoplasm occurred over a range of different proteins and was not confined to any one specific protein band. Additionally, the protein band most reduced over the course of laying did not contain elevated levels of the amino acids most limiting to egg production. These results indicate that during laying, flight muscle sarcoplasm contributes towards the nutrient requirements of egg production from general protein reserves, rather than from a specific storage protein containing elevated levels of limiting amino acids. [source] Congener-specific toxicokinetics of polychlorinated dibenzo- p -dioxins, polychlorinated dibenzofurans, and coplanar polychlorinated biphenyls in black-eared kites (Milvus migrans): Cytochrome P4501A,dependent hepatic sequestrationENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 4 2006Akira Kubota Abstract Concentrations of dioxins and related compounds (DRCs), such as polychlorinated dibenzo- p -dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and coplanar polychlorinated biphenyls (Co-PCBs), were determined in black-eared kites (BEKs; Milvus migrans) collected from the Kanto district in Japan. Total 2,3,7,8-tetra-CDD toxic equivalents (TEQs) were in the range of 99 to 3,800 pg/g lipid weight in the liver and 42 to 760 pg/g lipid weight in the pectoral muscle. Three congeners, including PCB 126, 2,3,4,7,8-penta-CDF, and 1,2,3,7,8-penta-CDD, made a greater contribution to total TEQs in both tissues. Levels of ethoxy-resorufin- O -deethylase activity and a cross-reactive protein with anti-rat cytochrome P4501A (CYP1A) polyclonal antibodies showed no significant correlation with hepatic TEQs. This may be attributed to low sensitivity and insufficient TEQ levels to cause CYP1A induction, high metabolic potential of a series of congeners, and influence of CYP1A inducers other than DRCs. Most of the PCDD/Fs and non- ortho Co-PCBs exhibited a total TEQ- and CYP1A-dependent increase in the liver to muscle concentration ratios, implying their concentration-dependent hepatic sequestration in which CYP1A was involved. Comparison of the toxicokinetics in avian species revealed that BEKs possibly have higher potentials than common cormorants for metabolizing and sequestering certain congeners in the liver in terms of hepatic concentration profiles and liver:muscle concentration ratios, respectively. These results clearly indicate that the toxicokinetics of DRCs is congener-, tissue-, and species-specific as well as concentration-dependent. Therefore, CYP1A expression is one of the critical factors that determine the toxicokinetics in wild avian species. [source] Ruddy turnstones Arenaria interpres rapidly build pectoral muscle after raptor scaresJOURNAL OF AVIAN BIOLOGY, Issue 5 2006Piet J. van den Hout To cope with changes in the environment, organisms not only show behavioural but also phenotypic adjustments. This is well established for the digestive tract. Here we present a first case of birds adjusting their flight machinery in response to predation risk. In an indoor experiment, ruddy turnstones Arenaria interpres were subjected to an unpredictable daily appearance of either a raptor or a small gull (as a control). Ruddy turnstones experiencing threat induced by a flying raptor model, longer than after similar passage by the gull model, refrained from feeding after this disturbance. Pectoral muscle mass, but not lean mass, responded in a course of a few days to changes in the perceived threat of predation. Pectoral muscle mass increased after raptor scares. Taking the small increases in body mass into account, pectoral muscle mass was 3.6% higher than aerodynamically predicted for constant flight performance. This demonstrates that perceived risk factors may directly affect organ size. [source] Analysis of the factors related with mate choice and reproductive success in male three-spined sticklebacksJOURNAL OF FISH BIOLOGY, Issue 5 2000E. R. Cubillos Territorial three-spined sticklebacks moved 5·3 times as far as non-territorial males in 2 min (P < 0·001) and spent 11·1 times longer in aggression in the pools (P< 0·001). Territorial males had slightly higher condition factors than non-territorial males. Condition factor was correlated positively with the gonad mass (P< 0·006), carotenoid concentration (P< 0·006) and the activity of CS in the axial muscle (P< 0·05) and lactate dehydrogenase (LDH) in pectoral muscle (P < 0·003). The male traits best correlated positively with female mate choice were courtship effort (P< 0·001), coloration (P< 0·003) and initial condition (P< 0·025). Courtship behaviour was related to intestine mass (P< 0·018), axial (P< 0·028) and pectoral muscle citrate synthase (CS) activity (P< 0·047); coloration was related to gonad mass (P< 0·037). These muscle enzymes may be involved in ATP generation for sustained activities or in recuperation between bouts of burst activity. Females that choose to mate with assiduously courting males which bear higher CS levels may be choosing individuals that show honestly their good condition and capacity to accomplish reproductive tasks. [source] Role of magnetic resonance imaging in the diagnosis and single-stage surgical resection of invasive lobular carcinoma of the breast,BRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 10 2002K. Munot Background: Conventional imaging with mammography and ultrasonography has a low sensitivity for diagnosis and a tendency to underestimate the extent of invasive lobular carcinoma (ILC) of the breast. The aim was to determine whether magnetic resonance imaging (MRI) had any advantages for the characterization of ILC. Methods: Twenty patients with histologically proven ILC underwent preoperative imaging with MRI. MRI was performed to aid detection of malignancy in six patients with a clinically suspicious presentation but normal or indeterminate imaging on mammography and ultrasonography. In 14 patients MRI was performed to determine tumour extent. Results: MRI accurately identified malignancy in five of six patients with normal or indeterminate conventional imaging. In seven of 14 patients in whom MRI was performed to determine tumour extent, it provided significant additional information. These included four patients in whom conventional imaging grossly underestimated tumour size, two patients in whom MRI identified an unsuspected contralateral breast tumour and one patient in whom MRI predicted tumour invasion of the pectoral muscle. The correlation between tumour size on histological examination was better with MRI (r = 0·967) than with mammography (r = 0·663) and ultrasonography (r = 0·673). Conclusion: MRI can provide considerable additional information in the detection and characterization of ILC. © 2002 British Journal of Surgery Society Ltd [source] Sex, diet and feeding method-related differences in body condition in the Oystercatcher Haematopus ostralegusIBIS, Issue 1 2001SARAH E.A. Measurements were made of Oystercatcher corpses to find the most reliable measure of body condition in live birds. Total body weight was as accurate as muscle thickness in assessing the weight of the pectoral muscles, a major store of protein reserves. Total body weight was also a good indicator of fat reserves. Wing-length was the most reliable measure of body size. Body condition in live birds was measured as an individual's residual weight derived from a general linear model of (loge) body weight against age, month, (loge) wing-length and time since capture. On the Exe estuary in autumn, there was no significant difference in body condition between same-age Oystercatchers of different diets and feeding methods. In the winter months, however, body condition differed significantly between mussel feeders using different feeding methods, and between mussel feeders and birds that fed on worms and clams. Differences between diet/feeding methods were not the same for each age group. Birds with the highest mean body condition index in adults were mussel hammerers, in immatures mussel stabbers and in juveniles, worm/clam feeders. No significant difference in body condition was found between the sexes in any age group in autumn. In winter, when birds with the same diet/feeding method were considered, females were significantly heavier than males. However, when birds of all diets and feeding methods were combined, weight differences between the sexes were not apparent. We examine reasons why birds with certain diets and feeding methods may be heavier than others in winter, and why females are sometimes heavier than males. We conclude that, in most cases, it is due to differences between birds in their ability to achieve a common target weight. However, we conclude that adult females try to achieve a higher target weight than males, probably as a premigratory and prebreeding strategy. In the light of this, we consider the consequences for adult females, in terms of reproductive success and survival, of specializing in diets and feeding methods associated with lower body weights in winter. [source] Phenotypic compromise in the face of conflicting ecological demands: an example in red knots Calidris canutusJOURNAL OF AVIAN BIOLOGY, Issue 1 2010François Vézina Phenotypic flexibility is a phenomenon where physiological functions in animals are reversibly adjusted in response to ecological constraints. Research usually focuses on effects of single constraints, but under natural conditions animals face a multitude of restrictions acting simultaneously, and potentially generating conflicting demands on the phenotype. We investigated the conflicting demands of low temperatures and a low quality diet on the phenotype of a shorebird, the red knot Calidris canutus. We tested the effects of switching diet from a high quality trout food to low quality hard-shelled bivalves in captive birds acclimated to temperatures reflecting natural winter conditions. Feeding on bivalves generated a digestive constraint forcing the birds to increase the height and width of their gizzard by 66% and 71%, respectively, over 30 days. The change in gizzard size was associated with an initial 15% loss of body mass and a reduction in size of the pectoral muscles by 11%. Because pectoral muscle size determines summit metabolic rate (Msum, an indicator of cold endurance), measured Msum declined by 9%. Therefore, although the birds were acclimated to cold, gizzard growth led to a loss of cold endurance. We propose that cold-acclimated knots facing a digestive constraint made a phenotypic compromise by giving-up cold hardiness for digestive capacity. Field studies suggest that phenotypic compromises occur in free-living red knots as well and help improve survival. [source] Changes in body mass and organ size during wing moult in non-breeding greylag geese Anser anserJOURNAL OF AVIAN BIOLOGY, Issue 6 2005Anthony D. Fox The "cost-benefit" hypothesis states that specific body organs show mass changes consistent with a trade-off between the importance of their function and cost of their maintenance. We tested four predictions from this hypothesis using data on non-breeding greylag geese Anser anser during the course of remigial moult: namely that (i) pectoral muscles and heart would atrophy followed by hypertrophy, (ii) leg muscles would hypertrophy followed by atrophy, (iii) that digestive organs and liver would atrophy followed by hypertrophy and (iv) fat depots be depleted. Dissection of geese captured on three different dates during wing moult on the Danish island of Saltholm provided data on locomotory muscles and digestive organ size that confirmed these predictions. Locomotory organs associated with flight showed initial atrophy (a maximum loss of 23% of the initial pectoral muscle mass and 37% heart tissue) followed by hypertrophy as birds regained the powers of flight. Locomotory organs associated with running (leg muscles, since geese habitually run to the safety of water from predator-type stimuli) showed initial hypertrophy (a maximum gain of 37% over initial mass) followed by atrophy. The intestines and liver showed initial atrophy (41% and 37% respectively), consistent with observed reductions in daily time spent feeding during moult, followed by hypertrophy. The majority of the 22% loss in overall body mass (mean 760 g) during the flightless period involved fat utilisation, apparently consumed to meet shortfalls between daily energetic needs and observed rates of exogenous intake. The results support the hypothesis that such phenotypic plasticity in size of fat stores, locomotor and digestive organs can be interpreted as an evolutionary adaptation to meet the conflicting needs of the wing moult. [source] Comparative anatomy, homologies and evolution of the pectoral muscles of bony fish and tetrapods: A new insightJOURNAL OF MORPHOLOGY, Issue 6 2007Rui Diogo Abstract The Osteichthyes, including bony fishes and tetrapods, is a highly speciose group of vertebrates, comprising more than 42,000 living species. The anatomy of osteichthyans has been the subject of numerous comparative studies, but most of these studies concern osteological structures; much less attention has been paid to muscles. The most detailed comparative analyses of osteichthyan pectoral muscles that were actually based on a direct observation of representatives of various major actinopterygian and sarcopterygian groups were provided several decades ago by authors such as Howell and Romer. Despite the quality of their work, these authors did not have access to much information that is now available. In the present work, an updated discussion on the homologies and evolution of the osteichthyan pectoral muscles is provided, based on the authors' own analyses and on a survey of the literature, both old and recent. It is stressed that much caution should be taken when the results obtained in molecular and developmental studies concerning the pectoral muscles of model actinopterygians such as the teleostean zebrafish are discussed and compared with the results obtained in studies concerning model sarcopterygians from clades such as the Amphibia and/or the Amniota. This is because, as shown here, as a result of the different evolutionary routes followed within the actinopterygian and the sarcopterygian clades none of the individual muscles found, for example, in derived actinopterygians such as teleosts is found in derived sarcopterygians such as tetrapods. It is hoped that the information provided in the present work may help in paving the way for future analyses of the pectoral muscles in taxa from different osteichthyan groups and for a proper comparison between these muscles in those taxa. J. Morphol., 2007. © 2007 Wiley-Liss, Inc. [source] Interpectoral approach to dissection of the Axillary Apex: An elegant and effective approachJOURNAL OF SURGICAL ONCOLOGY, Issue 3 2006Ajit Pai MS Abstract Background Axillary dissection is the goldstandard for treatment of the axilla. It provides important prognostic information, accurately stages the axilla, and has the lowest recurrence rate among all modalities. In today's age of conservation surgery, the axilla is often addressed through a cosmetically acceptable small incision with limited access, thereby making clearance of the level III nodes difficult. Methods We describe a method of apical lymph node dissection through the interpectoral plane, which effectively clears the apex despite the constraints of limited exposure. Results This method has been used in nearly 5,000 axillary dissections performed at our institute, with excellent results. It preserves the innervation of the pectoral muscles and affords access to the interpectoral nodes. Conclusions Our method has a short learning curve, provides good exposure of a difficult area and consistently provides a good yield of nodes. J. Surg. Oncol. 2006;94:252,254. © 2006 Wiley-Liss, Inc. [source] "Jerky" dystonia in children: Spectrum of phenotypes and genetic testing,MOVEMENT DISORDERS, Issue 5 2009Friedrich Asmus MD Abstract Hyperkinetic dystonia is characterized by phasic, tremulous, and "jerky" movements in addition to twisting postures. We studied longitudinally 23 index patients with hyperkinetic dystonia from a quaternary pediatric movement disorder clinic in Ireland. Four clinical categories emerged: (1) Eight patients were diagnosed with myoclonus-dystonia, of whom seven carried heterozygous epsilon sarcoglycan (SGCE) mutations, including a novel deletion of exon 10. Gait disorder, unsteadiness, or frequent falls before 18 months were detected in all SGCE mutation carriers, whereas the typical neck-predominant presentation developed only years later. (2) One patient classified as benign hereditary chorea, because jerks were choreiform and continuous rather than action-induced, carried a heterozygous stop mutation of the TITF -1 gene (Y114X, exon 2). (3) Three mutation-negative patients were grouped as "myoclonic dystonia" with jerks only in the body regions affected by dystonia. (4) Eleven patients presented with a novel combination of dystonia and low amplitude poly-mini myoclonus of the upper limbs and pectoral muscles (D-PMM). In early childhood up to 3 years of age, an initial presentation with predominant gait impairment with only subtle jerks should prompt consideration of SGCE mutation analysis in addition to testing for DYT1 mutations. A causative gene for D-PMM remains to be identified. © 2008 Movement Disorder Society [source] | |||||||||||||