Spoilage association of chicken leg muscle.

The ability of pure cultures of bacteria isolated from spoiling chicken leg muscle to produce strong off-odors was tested by using sterile leg muscle sections. Changes in the flora during storage and the incidence and identity of organisms capable of producing strong off-odors were noted.     

Spoilage association of chicken skin.

The bacterial succession on the skin of broiler chicken carcasses stored at 2 degrees C was traced, and the ability of representative isolates to produce off-odors was determined by using sterile leg and breast muscle sections. Off-odors were identified by olfactory and chemical means. The inability of peptone-iron agar to detect sulfide-producing strains was noted.     

Spoilage association of chicken skin.

The bacterial succession on the skin of broiler chicken carcasses stored at 2 degrees C was traced, and the ability of representative isolates to produce off-odors was determined by using sterile leg and breast muscle sections. Off-odors were identified by olfactory and chemical means. The inability of peptone-iron agar to detect sulfide-producing strains was noted.     

Characterization of Hydrogen Sulfide-Producing Bacteria Isolated from Meat and Poultry Plants

A survey of the types of aerobic organisms able to produce H2S on peptone iron agar (Levin, 1968), and commonly occurring in meat and poultry plants, revealed that these could be divided into four distinct groups. The ability of representative strains of each type to grow at low temperatures and cause off-odors on chicken muscle was examined. The results are discussed in relation to the role of these organisms in the psychrophilic spoilage of meat and meat products.     

Hydrogen Sulfide Production by Pseudomonas putrefaciens in Shrimp Experimentally Packed in Nitrogen

Shrimp refrigerated in a nitrogen atmosphere develop off-odors not typical of normal spoilage. Investigations of this phenomenon showed that hydrogen sulfide developed in the headspace gas, and a large percentage of the microbial population present on the shrimp stored in nitrogen was capable of hydrogen sulfide production, in contrast to the flora on shrimp stored in air. The predominant hydrogen sulfide-producing organism, Pseudomonas putrefaciens, was present in low numbers on fresh shrimp but usually reached high numbers by day 8 of nitrogen storage. Further studies revealed that cysteine and cystine were the probable substrates in shrimp utilized by this organism for hydrogen sulfide production. When shrimp sterilized by irradiation were inoculated with P. putrefaciens and incubated in an atmosphere of nitrogen, hydrogen sulfide and the characteristic off-odors developed.     

The components of troponin from chicken fast skeletal muscle. A comparison of troponin T and troponin I from breast and leg muscle.

The three components of troponin were prepared from chicken breast and leg muscle. The troponin I and T components were separated by chromatography on DEAE-cellulose after citraconylation and without the use of urea-containing buffers. The troponin I and C components were similar to their counterparts from rabbit fast skeletal muscle, and a comparison of the troponin I components from breast and leg muscle by amino acid analysis, gel electrophoresis and peptide 'mapping' provides strong evidence for the identity of these proteins. The molecular weights of the troponin T components from breast and leg muscle were 33 500 and 30 500 respectively, determined by gel filtration. A comparison of these two proteins by methods similar to those used for the troponin I components suggested that they differed only in the N-terminal region of the sequence, the breast-muscle troponin T having an extra length of polypeptide chain of approx. 24 residues that is rich in histidine and alanine. The N-terminal hexapeptide sequence, however, is the same in both proteins and is (Ser,Asx,Glx)Thr-Glu-Glu. The genetic implications of these findings are considered.     

Prospective analysis of the outcome of subpectoral breast augmentation: sensory changes, muscle function, and body image

This study is a prospective analysis of the outcome of subpectoral breast augmentation. Forty-seven patients undergoing breast augmentation were studied. They were assessed for pectoralis muscle function, breast sensation, and body image before and after subpectoral breast augmentation with saline implants. The patients were evaluated as follows: Pectoralis function was determined by measuring maximal voluntary isometric force. Sensation was evaluated by two means: vibration and pressure. The patient's body image was assessed using the Multidimensional Body-Self Relations Questionnaire. Results indicated a significant change in breast sensation at 3 months postoperatively but not at 6 months. Pectoralis muscle function did not significantly change during the study period. Body image was significantly improved at both postoperative measuring periods. The authors conclude that breast augmentation results in improved body image with negligible effect on muscle or nerve function.     

Extracellular Enzymic Activity of Poultry Spoilage Bacteria

The extracellular enzymic activity has been studied of 224 strains of bacteria isolated mainly at 1° from spoiling chickens and turkeys and from poultry processing plants. The isolates comprised 44 strains of pigmented Pseudomonas , 57 strains of nonpigmented Pseudomonas , 29 strains of Ps. putrefaciens , 50 strains of oxidase positive Acinetobacter and 44 strains of oxidase negative Acinetobacter. None of the strains showed any significant activity against dextrin, starch, glycogen, inulin, dextran, xylan or pectin. Proteolytic activity was found mainly amongst 2 groups of pigmented pseudo-monads, and Ps. putrefaciens. Nuclease activity was found particularly amongst strains of Ps. putrefaciens and the oxidase negative Acinetobacter strains isolated from spoiling poultry. Almost all of the strains showed lipolytic activity when tested with tributyrin and a proportion of strains could also attack chicken fat. This latter property was particularly evident amongst the nonpigmented Pseudomonas strains.     

Decreased mitochondrial creatine kinase activity in dystrophic chicken breast muscle alters creatine-linked respiratory coupling

Dystrophic chicken breast muscle mitochondria contain significantly less mitochondrial creatine kinase than normal breast muscle mitochondria. Breast muscle mitochondria from normal 16- to 40-day-old chickens contain approximately 80 units of mitochondrial creatine kinase per unit of succinate:INT (p-iodonitrotetrazolium violet) reductase, a mitochondrial marker, while dystrophic chicken breast muscle mitochondria contain 36-44 units. Normal chicken heart muscle mitochondria contain about 10% of the mitochondrial creatine kinase per unit of succinate:INT reductase as normal breast muscle mitochondria. The levels in heart muscle mitochondria from dystrophic chickens are not affected significantly. Evidence is presented which shows that the reduced level of mitochondrial creatine kinase in dystrophic breast muscle mitochondria is responsible for an altered creatine linked respiration. First, both normal and dystrophic breast muscle mitochondria respire with the same state 3 and state 4 respiration. Second, the post-ADP state 4 rate of respiration of normal breast muscle mitochondria in the presence of 20 mM creatine continues at the state 3 rate. However, the state 4 rate of dystrophic breast muscle mitochondria and mitochondria from other muscle types with a low level of mitochondrial creatine kinase, such as heart muscle and 5-day-old chicken breast muscle, is slower than the state 3 rate. Third, dystrophic breast mitochondria synthesize ATP at the same rate as normal breast muscle mitochondria but rates of creatine phosphate synthesis in 20-50 mM Pi are reduced significantly. Finally, increasing concentrations of Pi displace mitochondrial creatine kinase from mitoplasts of normal and dystrophic breast muscle mitochondria with the same apparent KD, indicating that the outer surface of the inner mitochondrial membrane and the mitochondrial creatine kinase from dystrophic muscle are not altered.     

Respiratory capacity of developing chick red and white skeletal muscle

Oxygen consumption, cytochrome oxidase and succinoxidase activity was measured in samples of leg and breast muscle from chick embryos ranging in age from 11 to 19 days. Respiratory parameters increased significantly in both muscle groups during embryonic life. By the later stages of incubation, leg and breast muscles differed significantly in cytochrome and succinoxidase activity. Oxygen uptake between leg and breast muscles did not differ significantly during later development. The results suggest at least a partial pre-natal differentiation of skeletal muscle in the domestic fowl.     

Myoglobin synthesis in cell cultures of red and white muscle

Myoglobin synthesis was compared in cell cultures of leg (red) and breast (white) muscle of chick embryos. In leg muscle cultures a rapidly increasing amino acid incorporation into myoglobin begins two days after muscle cell fusion; in breast muscle cultures no comparable increase was observed. This qualitative difference in cultures of the two muscle cell types provides possibilities for the further study of the mechanism of myoglobin synthesis.     

Expression of multiple troponin T variants in neonatal chicken breast muscle

The types of troponin-T (TNT) expressed in neonatal chicken breast muscle were examined by two-dimensional gel electrophoresis (2-D PAGE), immunoblotting, and peptide mapping. When troponin from neonatal chicken breast muscle or whole lysate of the muscle was displayed on 2-D PAGE, multiple spots were observed in the TNT region on the gel. They differed slightly from those in adult breast- and leg-type TNT, but were positively stained with the antibody specific for TN-T. These results indicate that multiple spots observed in the TNT region are all TNT isoforms. The TNT isoforms in the neonatal breast muscle were classified into two groups, based on size. Each group contained about five variants. The first group with a larger size was in the molecular weight range of adult breast TNT, while the smaller-sized second group was in the molecular weight range of adult leg TNT. Overall peptide map patterns of variants in the first group and also that of adult breast TNT resembled each other, whereas those of variants in the second group were similar to that of adult leg TNT. The TNT of adult breast-type appeared at about 2- to 3-weeks posthatch, and thereafter became a major TNT isoform.     

Identification and characterization of genes related to the development of breast muscles in Pekin duck

Pekin Duck is world-famous for its fast growth, but its breast muscle development is later and breast muscle content is lower compared with other muscular ducks. Therefore, it is very important to discover the genetic mechanism between breast muscle development and relative gene expression in Pekin duck. In current study, the genes which have relationships with breast muscle development were identified by suppression subtractive hybridization. A total of 403 positive clones were sequenced and 257 unigenes were obtained. The expression of 23 genes were analyzed in the breast muscle of 2-, 4-, 6-, 8- week old Pekin ducks. The results showed that unknown clone A233, C83 and C99 showed descending tendency as age increased; KBTBD10, HSPA8, MYL1, ZFP622, MARCH4, Nexilin, FABP4 and MUSTN1 had high expression levels at 6 weeks old; WAC, NT5C3, HSP90AA1, MRPL33, KLF6, TSNAX, CDC42EP3, HSPA4, TRAK1, NR2F2, HAUS1 and IGF1 had high expression levels at 8 weeks and showed ascending tendency as age increased. Expression of these 23 genes were also analyzed in breast muscle, leg muscle, heart, kidney, liver, muscular stomach and sebum cutaneum in 4-8-week old Pekin duck and results showed that most of these genes had high expression in breast muscle, leg muscle and heart.     

THE STRUCTURE OF PIGEON BREAST MUSCLE MITOCHONDRIA

The structure of pigeon breast muscle mitochondria was studied both in whole muscle tissue and in mitochondrial fractions separated by differential centrifugation. No evidence was found to indicate that the mitochondria of pigeon breast muscle differ in any fundamental way from those of other tissues. In particular the absence of an enveloping membrane, claimed in recent reports, was not confirmed. The structure of the lipide bodies present in muscle has been described, and compared with that of similar bodies in other tissues.     

M-protein in chicken cardiac muscle.

Chicken cardiac muscle myofibrils lack a visible M-line. Antibodies against chicken breast muscle M-protein, an M-line component with M_r = 165 000, were used to demonstrate the presence of a similar protein in chicken heart muscle. The immunoreplica technique showed the heart protein to have about the same molecular weight as the breast muscle M-protein on polyacrylamide slab gels in the presence of sodium dodecyl sulfate (SDS). Positive staining within the H-zone was observed when the indirect immunofluorescence technique was used to localize the M-protein in isolated heart myofibrils. This result was confirmed by electron microscopic investigations on longitudinal sections of antibody-incubated heart muscle fiber bundles showing the antibody against M-protein to be bound within a region corresponding to the M-line region of breast muscle myofibrils.     

Does overfeeding enhance genotype effects on energy metabolism and lipid deposition in breast muscle of ducks?

We evaluated the effects of genotype (Muscovy, Pekin and their crossbreed hinny and mule ducks) and feeding levels (overfeeding between 12 and 14 weeks of age vs ad libitum feeding) on energy metabolism and lipid deposition in breast muscle of ducks. Samples of breast muscle (Pectoralis major) were collected at 14 weeks of age from 8 birds per group. Overfeeding induced an accumulation of lipids in breast muscle (1.5- to 1.7-fold, depending on genotype) mainly induced by triglyceride deposition. It also induced a considerable increase in the amounts (expressed as g/100 g of tissue) of saturated and mono-unsaturated fatty acids (SFA, MUFA), while the amounts of poly-unsaturated fatty acids (PUFA) remained unchanged in hinny and Muscovy ducks or slightly increased in Pekin and mule ducks. In breast muscle, overfeeding decreased the activity of the main enzymes involved in lipogenesis from glucose (glucose-6-phosphate dehydrogenase, G6PDH, malic enzyme, ME, acetyl CoA carboxylase, ACX). Lipoprotein lipase (LPL) activity in Pectoralis major muscle was also significantly decreased (-21%). The ability of muscle tissues to catabolize long-chain fatty acids, as assessed by beta-hydroxyacyl CoA dehydrogenase (HAD) activity, was increased in Pectoralis major muscle, as was cytochrome-c oxidase (COX) activity. Hybrid and Pekin ducks exhibited higher levels of ACX and LPL activity in Pectoralis major muscle than Muscovy ducks, suggesting a greater ability to synthesise lipids in situ, and to take up circulating lipids. Total lipid content in breast muscle of hybrid and Pekin ducks was higher than in that of Muscovy ducks. In hybrid and Pekin ducks, lipid composition of breast muscle was characterized by higher amounts of triglycerides, SFA and MUFA than in Muscovy ducks. Finally, oxidative metabolism was greater in Pectoralis major muscles of hybrid and Pekin ducks than in Muscovy ducks, suggesting an adaptative strategy of muscle energy metabolism according to lipid level.     

即时扩展型背阔肌肌皮瓣乳房再造在保留乳头乳晕复合体乳癌术后的运用分析

目的：探讨分析即时扩展型背阔肌肌皮瓣乳房再造在保留乳头乳晕复合体乳癌术后的运用。方法：回顾性分析我院2008年2月-2012年4月收治的乳腺癌术后患者106例,采用乳癌术即时扩展型背阔肌肌皮瓣乳房再造保留乳头乳晕复合体,观察手术效果以及满意度。结果：术后患者乳房美容优良率为88．68％明显大于对照组的47．17％,并且术后6个月治疗组生活质量评价总分明显大于对照组总分术后6个月患者生活质量评价总分明显大于术前评价总分,差异具有条件下意义（P〈0．05）,差异均具有统计学意义（P〈0．05）。结论：即时扩展型背阔肌肌皮瓣乳房再造在保留乳头乳晕复合体乳癌术后患者乳房美容效果较好,提高患者生活质量高,值得在临床上推广,但在手术后需积极处理可能存在的并发症情况。     

31P NMR Investigation of vanadium-treated chick muscle

The phosphorus NMR profile of normal and vanadium-treated chick muscle was obtained in vivo. The data show that the differentiation of breast and thigh muscles in terms of pH, lipid related metabolites, and bioenergetic parameters can be readily followed. Although the vanadium-treated chicks showed substantial retardation of growth, the only NMR parameter that was significanty affected by dietary vanadium was the pH of breast muscle, which was substantially more acidic in the vanadium-treated animals.     

Biosynthesis of tropomyosin and troponin during development of the chicken skeletal muscle

The level of functional mRNA coding for myofibrillar proteins was studied during development of the chicken skeletal muscle. RNA isolated from the developing chicken muscle directed protein synthesis in a wheat germ cell-free system. By means of polyacrylamide gel electrophoresis and immunological analysis, tropomyosin subunits and troponin components were identified among the cell-free translation products. The mRNA activities for alpha- and beta-subunit of tropomyosin were prominent in the embryonic breast muscle as well as in the embryonic leg muscle. At the early post-embryonic stage, the mRNA activity for beta-subunit disappeared from the breast muscle, while those for alpha- and beta-subunit were detectable in the leg muscle. Troponin-C and troponin-I synthesized in vitro in response to the muscle RNA formed a binary complex in the presence of calcium ion. Despite the observed difference in molecular weight between troponin-Ts in the breast and leg muscle, RNA preparations from the two muscles encoded identical troponin-Ts whose molecular weights were indistinguishable from that of troponin-T present in the breast muscle of adult chicken. It is suggested from these results that the biosynthesis of tropomyosin is regulated at the pre-translational level during the development of the chicken skeletal muscle, whereas post-translational (or co-translational) events may produce the tissue-specific form of troponin-T.