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Force Transmission between Synergistic Skeletal Muscles through Connective Tissue Linkages
Huub Maas,Thomas G. Sandercock
Journal of Biomedicine and Biotechnology , 2010, DOI: 10.1155/2010/575672
Abstract: The classic view of skeletal muscle is that force is generated within its muscle fibers and then directly transmitted in-series, usually via tendon, onto the skeleton. In contrast, recent results suggest that muscles are mechanically connected to surrounding structures and cannot be considered as independent actuators. This article will review experiments on mechanical interactions between muscles mediated by such epimuscular myofascial force transmission in physiological and pathological muscle conditions. In a reduced preparation, involving supraphysiological muscle conditions, it is shown that connective tissues surrounding muscles are capable of transmitting substantial force. In more physiologically relevant conditions of intact muscles, however, it appears that the role of this myofascial pathway is small. In addition, it is hypothesized that connective tissues can serve as a safety net for traumatic events in muscle or tendon. Future studies are needed to investigate the importance of intermuscular force transmission during movement in health and disease.
Isolation of Escherichia coli from lymph nodes of bovine carcasses and detection of hlyA gene with PCR  [cached]
P. Sechi,V. Cambiotti,S. Parmegiani,C. Baldinelli
Italian Journal of Food Safety , 2012, DOI: 10.4081/ijfs.2012.5.23
Abstract: A potential source of pathogenic bacteria in ground beef is the lymphatic system, specifically the lymph nodes. The objective of the current study was to determine the prevalence of Escherichia coli in bovine lymph nodes. Bovine lymph nodes (n = 200) were collected from 100 carcasses at a commercial slaugh-terhouse. 192 lymph nodes sampled were obtained from 96 regular slaughter, and the remainder 8 were obtained from 4 emergency slaughter. Subiliaci lymph nodes were collected for this study. E. coli preva-lence in the lymph node samples was high, with an overall prevalence of 59.00%. Lymph nodes from emergency slaughter carcasses had a higher prevalence (75.00%) of E. coli than did those from regular slaughter carcasses (58.33%). hlyA gene was never detected.
Simultaneous occurrence of selected food-borne bacterial pathogens on bovine hides, carcasses and beef meat
K. Wieczorek , J. Osek
Polish Journal of Veterinary Sciences , 2010, DOI: 10.2478/v10181-010-0001-8
Abstract: The aim of this study was to determine the simultaneous occurence of Salmonella spp., L. monocytogenes, verotoxigenic E. coli (VTEC), and Campylobacter spp. in slaughtered cattle and in beef meat subjected for human consumption. A total of 406 bovine hides and 406 corresponding carcasses were used to collect the samples with a swab method after exsanguination and evisceration of animals, respectively. Furthermore, 362 beef meat samples were purchased in local retail shops over the same period of time as for the bovine samples. Food-borne bacterial pathogens were identified with standard ISO methods with some modification by the use of PCR for VTEC. The isolated bacteria were then molecularly speciated (Campylobacter), serotyped (L. monocytogenes) and characterized for the presence of several virulence marker genes (VTEC and Campylobacter). It was found that 49 hide (12.1%) and 3 (0.7%) carcass samples were contaminated with more than one bacterial pathogen tested. Most of the hides were positive for Campylobacter spp. and VTEC (27 samples) and Campylobacter spp. together with L. monocytogenes (12 samples). Eight bovine hides contained L. monocytogenes and VTEC while L. monocytogenes and Salmonella spp. were detected in one sample. Furthermore, 3 pathogens (Campylobacter spp., L. monocytogenes and VTEC) were simultaneously identified in one bovine hide tested. In case of bovine carcasses 2 samples contained Campylobacter spp. and VTEC whereas one carcass was positive for L. monocytogenes and VTEC. On the other hand, 10 out of 362 (2.8%) minced beef samples were contaminated with at least two pathogens tested. The majority of these samples were contaminated with L. monocytogenes and Salmonella spp. (6 samples). It was noticed that equal number of C. jejuni and C. coli were found, irrespective of the origin of the samples. Most of the strains possessed more than one pathogenic factor as identified by PCR. Molecular serotyping of L. monocytogenes revealed that the majority of the isolates (27 out of 31; 87.1%) belonged to 1/2a serogroup. It was found that most of the VTEC isolates possessed the Shiga toxin stx2 gene (12 strains) whereas only 2 strains were stx1-positive. The eneterohemolysin and intimin markers were identified only in 7 and 2 isolates, respectively. PCR analysis revealed that 4 VTEC belonged to O91 serogroup, 2 strains were O145 and 1 isolate was identified as O113. None of the VTEC detected in the study was O157 serogroup.
Encurtamento pelo frio de fibras musculares oxidativas de bovinos pela técnica de NADH-TR
Fernandes, Juliana Maria Pereira Felício Gonfiantini;Pinto, Marcos Franke;Ponsano, Elisa Helena Giglio;Almeida, Ana Paula da Silva;Abreu, Urbano Gomes Pinto de;Lara, Jorge Antonio Ferreira de;
Ciência Rural , 2006, DOI: 10.1590/S0103-84782006000600033
Abstract: bovine carcasses quickly cooled may develop a muscle contraction known as cold shortening. this process, harmful to meat texture, occurs mainly in the oxidative muscle fibers. this work was aimed at studing an analytical tool to distinguish these fibers and to evaluate, more precisely, the muscle contraction through the measurement of sarcomeres length. longissimus dorsi muscles of 12 heifers were used as samples. samples from one of the half carcasses were fast cooled and the samples from the others half carcasses were slowly cooled. an analytical technique based on nicotinamide adenine dinucleotide - tetrazolium redutase (nadh-tr) methodology was performed to measure, by microscopy, the red fibers sarcomeres lenghts. temperature and ph drops in the samples, shear force and rib eye area were also evaluated. results pointed out that the temperature is the main responsible for the sarcomere length in the fast cooling and that, when slow cooling is performed, the influence of this parameter is less important. these results indicate that the nadh-tr technique is able to estimate cold shortening occurrence in bovine skeletal muscles.
Ultrastructural Study of Muscles Fibers in Tick Hyalomma (Hyalomma) anatolicum anatolicum (Ixodoidea: Ixodidae)  [PDF]
Faisal A. Bughdadi
Pakistan Journal of Biological Sciences , 2010,
Abstract: In the present study, ticks were obtained from a colony maintained at 28 °C and 75% relative humidity in at the Department of Biology, University College Umm Al-Qura University, Saudi Arabia and the Transmission Electron Microscope technique (TEM) was used to describes the ultrastructure and description of muscle of the of ixodid tick Hyalomma (Hyalomma) anatolicum anatolicum. The results showed that muscles of the unfed ticks Hyalomma (Hyalomma) anatolicum anatolicum in longitudinal sections are spindle-shaped to cylindrical muscle fibers. In the unfed nymph Hyalomma (Hyalomma) anatolicum anatolicum skeletal and visceral muscles are distinguished according to structure, function and position. These muscles include the capitulum, dorsoventral and leg oblique muscles. All muscle fibers are ensheathed (covered by sheath) in a sarcolemma. Their muscle fibers have striated pattern of successive sarcomeres whose thick myosin filaments are surrounded by orbitals of up to 12 thin actin filaments. The cytoplasm of the epidermal cell appears largely devoted with complicated microtubules present in parallel with long axis of adjacent muscle fibers. The cell membrane invaginates into tubular system extending deeply into the sarcoplasm and closely associated to cisternae of sarcoplasmic reticulum. The tubular system and sarcoplasmic reticulum forming two-membered (dyads) are considered to be the main route of calcium ions whose movement are synchronized with the motor impulse to control muscles contraction. In the sarcoplasm two types of muscle fibers are recognized according to thickness and density and mitochondrial size, distribution and population. Both skeletal and visceral muscles are invaginated by tracheoles and innervated by nerve axons containing synaptic vesicles. The actin and myosin filaments are slightly interrupted and the tubular system sarcoplasmic reticulum is well demonstrated.
Histological Description of the Interaction Between Muscle Fibers and Connective Tissue of the Fascia of the Human Trapezius Muscle
Rodriguez,H; Espinoza-Navarro,O; Silva,I; Quiroz,P; Arriaza,C; Sanchez,C; Vallejos,R; Castro,M. E; Arias,M; Jimenez,L; Fernandez,E;
International Journal of Morphology , 2011, DOI: 10.4067/S0717-95022011000100049
Abstract: the skeletal muscle fascia corresponds to a condensation of connective tissue. fascias are highly innervated and sensitive, and can cover non-expandable structures as well as musculature. it is suggested that fascias have a pivotal role in functions such as postural regulation, peripheral motor coordination and proprioception. also, the presence of inflammation and microcalcification in fascia of patients with localized muscle pain has been described, suggesting a pathogenic role in pain. the aim was to describe the histological structure of the external deep fascia of the trapezius muscle, with emphasis on the content and arrangement of muscle fibers, type i collagen, and adipose tissue. sample material was obtained from a male cadaver (60-70 years old), by dissection of the posterior cervical region of the superficial fascia of the trapezius muscle and fixed in buffered formalin. samples were processed by routine histological techniques and embedded in paraffin, obtaining 5 μm-thick sections that were stained according to the van gieson technique. the trapezius fascia is composed of type i collagen, organized into high-density collagen bundles and oriented in different directions, and by adipocytes disposed in longitudinal groups on the main axis of the fascia. muscle fibers are organized into bundles that are inserted laterally on the thickness of the fascia. it is possible that lateral transmission of tensional forces between the fibers might be present.
Control of Taenia saginata by post-mortem examination of carcasses
W Wanzala, J A Onyango-Abuje, E K Kang'ethe, K H Zessin, N M Kyule, H Ochanda, L JS Harrison
African Health Sciences , 2003,
Abstract: Background: A study to curb transmission cycle of a zoonotic Taema cestodiasis between humans and cattle is presented. Objective: To evaluate the reliability of meat inspection procedure in detecting carcasses of cattle with T. saginata cysticercosis. Methods: A total of 55 cattle divided into two groups of artificially (n =30) and naturally (n = 25) infested animals were utilized. Total dissection method was used as a gold standard of validity. Results: Meat inspection insensitively revealed cysticerci in 12 carcasses in each group compared with 24 and 23 carcasses revealed by total dissection in natural and artificial infestations, respectively. Sites of oncosphere invasion showed great variations with the two groups of cattle. In the predilection sites, most cysticerci were found in the heart, Triceps brachii, tongue and head muscles in that order. However, non-predilection sites (neck and back, hind limbs, chest, pelvic and lumbar regions, lungs and liver) considerably harboured high numbers of cysticerci. Observations indicated that except for the dead, degenerate or calcified cysticerci a careless meat inspector will most likely miss out quite a number of viable cysticerci, which blend the pinkish-red colour of the meat and be passed on for human consumption, becoming the source of bovine cysticercosis. Conclusions: The results confirmed that in spite of the time and efforts taken by meat inspectors looking for cysticerci at specified predilection sites of carcasses, this method is insensitive and inaccurate. To effectively improve meat inspection procedures, there is need to increase the area and number of predilection sites observed during inspection and vary them according to the nature of the animals, their husbandry history and the target human population for consumption. In addition, other control approaches such as vaccination, chemotherapy and immunodiagnosis should be developed and implemented to complement meat inspection procedures. African Health Sciences 2003 3(2); 68-76
The Union Between Gracilis and Sartorius Muscles in Leontopithecus: Morphofunctional Analysis
Marques,M. A.; Vasconcellos,H. A.; Azevedo,N. L.;
International Journal of Morphology , 2006, DOI: 10.4067/S0717-95022006000300016
Abstract: the golden lion tamarin (leontopithecus rosalia) is an endemic primate of the brazilian atlantic coastal rainforest, still under serious extinction risk. just a few is know about its anatomy, specifically the muscle unions. due to the reasons exposed before, aiming understanding the locomotion of this and others primates, we decided to study the morphology and morphometry of the gracilis and sartorius muscles, and the relation between them, in three leontopithecus species. the current study examined 18 adult animal carcasses, of both sexes and with no physical abnormalities on the studied region. the material belongs to the rio de janeiro primatology center collection. the posterior members were dissected till the gracilis and sartorius muscles level, when were executed the morphometry, obtaining the cross section area and the histological analysis of the macroscopic between the gracilis muscle and the sartorius muscle. we described the morphology of the gracilis muscle and sartorius muscle, obtained the average muscle morphometry values and studied, histologically, the union between these muscles. the morphological and morphometric analysis allow us suggest descriptive parameters for these muscles the histological analysis allow us conclude the gracilis muscle and sartorius muscle fibers are not linked, but kept together by a conjunctive tissue, thus, being inserted into the medial side of the tibia. functionally, we believe the gracilis muscle and the sartorius muscle shall contribute on the active containment of the knee joint and on the biomechanics of the posterior members, of these primates, known as runners
Prevalence of bovine cysticercosis and hydatidosis in Jimma municipal abattoir, South West Ethiopia  [cached]
T. Tolosa,W. Tigre,G. Teka,P. Dorny
Onderstepoort Journal of Veterinary Research , 2010, DOI: 10.4102/ojvr.v76i3.37
Abstract: A cross-sectional study to determine the prevalence of bovine cysticercosis and hydatidosis was conducted from October 2007 to March 2008 in cattle slaughtered at the Jimma municipal abattoir. Cyst distribution and viability of bovine cysticercosis and hydatidosis were also determined. A total of 512 carcasses were inspected of which 15 (2.93 %) and 161 (31.44 %) were infected with Taenia saginata metacestodes and hydatid cysts, respectively. From a total of 109 cysticerci collected from infected carcasses, 47 (43.12 %) were viable. The anatomical distribution of the cysticerci was, shoulder muscle (39.5 %), heart (33.9 %), neck muscle (13.8 %), tongue (10.1 %), masseter muscles (1.8 %) and diaphragm (0.9 %). Of the 1171 hydatid cysts collected 223 (19.0 %) were fertile, 505 (43.1 %) sterile, 49 (29.8 %) calcified and 94 (8.0 %) contained pus. A greater proportion of fertile cysts were found in the lungs than in other organs. It was concluded that these zoonotic cestodes deserve due attention to safeguard public health, and that further studies are needed on genotyping, epidemiology and public health importance of Echinococcus granulosus in the study area.
Bovine serum albumin potentiates caffeine- or ATP-induced tension in human skinned skeletal muscle fibers
Brazilian Journal of Medical and Biological Research , 1997, DOI: 10.1590/S0100-879X1997000500017
Abstract: human skinned muscle fibers were used to investigate the effects of bovine serum albumin (bsa) on the tension/pca relationship and on the functional properties of the ca2+-release channel of the sarcoplasmic reticulum (sr). in both fast- and slow-type fibers, identified by their tension response to psr 5.0, bsa (0.7-15 μm) had no effect on the ca2+ affinity of the contractile proteins and elicited no tension per se in ca2+-loaded fibers. in contrast, bsa (>1.0 μm) potentiated the caffeine-induced tension in ca2+-loaded fibers, this effect being more intense in slow-type fibers. thus, bsa reduced the threshold caffeine concentration required for eliciting detectable tension, and increased the amplitude, the rate of rise and the area under the curve of caffeine-induced tension. bsa also potentiated the tension elicited in ca2+-loaded fibers by low-mgv solutions containing 1.0 mm free atp. these results suggest that bsa modulates the response of the human skeletal muscle sr ca2+-release channel to activators such as caffeine and atp.
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