Different forms of 130 kD connective tissue protein are specific for boundaries in the nervous system and basement membrane of muscle cells in leech

1993 ◽  
Vol 24 (11) ◽  
pp. 1531-1542 ◽  
Author(s):  
Irmgard Thorey ◽  
Birgit Zipser
1988 ◽  
Vol 107 (3) ◽  
pp. 1189-1198 ◽  
Author(s):  
M Chiquet ◽  
L Masuda-Nakagawa ◽  
K Beck

Leech neurons in culture sprout rapidly when attached to extracts from connective tissue surrounding the nervous system. Laminin-like molecules that promote sprouting have now been isolated from this extracellular matrix. Two mAbs have been prepared that react on immunoblots with a approximately equal to 220- and a approximately equal to 340-kD polypeptide, respectively. These antibodies have been used to purify molecules with cross-shaped structures in the electron microscope. The molecules, of approximately equal to 10(3) kD on nonreducing SDS gels, have subunits of approximately equal to 340, 220, and 160-180 kD. Attachment to the laminin-like molecules was sufficient to initiate sprouting by single isolated leech neurons in defined medium. This demonstrates directly a function for a laminin-related invertebrate protein. The mAbs directed against the approximately equal to 220-kD chains of the laminin-like leech molecule labeled basement membrane extracellular matrix in leech ganglia and nerves. A polyclonal antiserum against the approximately equal to 220-kD polypeptide inhibited neurite outgrowth. Vertebrate laminin did not mediate the sprouting of leech neurons; similarly, the leech molecule was an inert substrate for vertebrate neurons. Although some traits of structure, function, and distribution are conserved between vertebrate laminin and the invertebrate molecule, our results suggest that the functional domains differ.


Author(s):  
B. Faris ◽  
L.L. Salcedo ◽  
V. Cook ◽  
L. Johnson ◽  
J.A. Foster ◽  
...  

2017 ◽  
Vol 24 (13) ◽  
pp. 1743-1752 ◽  
Author(s):  
Matteo Gastaldi ◽  
Enrico Marchioni ◽  
Paola Banfi ◽  
Valeria Mariani ◽  
Laura Di Lodovico ◽  
...  

Background: Transverse myelitis (TM) is an inflammatory disorder that can be idiopathic or associated with central nervous system autoimmune/dysimmune inflammatory diseases, connective tissue autoimmune diseases, or post-infectious neurological syndromes. Prognosis of initial TM presentations is uncertain. Objective: To identify outcome predictors in TM. Methods: Retrospective study on isolated TM at onset. Scores ⩾3 on the modified Rankin scale (mRS) marked high disability. Results: A total of 159 patients were identified. TM was classified as follows: idiopathic (I-TM, n = 53), post-infectious (PI-TM, n = 48), associated with multiple sclerosis (MS-TM, n = 51), or neuromyelitis optica spectrum disorders/connective tissue autoimmune diseases/neurosarcoidosis ( n = 7). At follow-up (median, 55 months; interquartile range, 32–80), 42 patients were severely disabled, and patients with I-TM or PI-TM showed the worst outcomes. Predictors of disability were infectious antecedents, sphincter and pyramidal symptoms, high mRS scores, blood–cerebrospinal fluid barrier damage, lumbar magnetic resonance imaging (MRI) lesions on univariate analysis, and older age (odds ratio (OR), 1.1; 95% confidence interval (CI), 1.0–1.1), overt/subclinical involvement of the peripheral nervous system (PNS) (OR, 9.4; 95% CI, 2.2–41.0), complete TM (OR, 10.8; 95% CI, 3.4–34.5) on multivariate analysis. Conclusion: Our findings help define prognosis and therapies in TM at onset. Infectious antecedents and PNS involvement associate with severe prognosis. Nerve conduction studies and lumbar MRI could improve the prognostic assessment of this condition.


1989 ◽  
Vol 67 (3) ◽  
pp. 1063-1069 ◽  
Author(s):  
J. G. Tidball ◽  
M. Chan

Whole muscles loaded to failure frequently fail at or near myotendinous junctions. The present investigation was directed toward determining the breaking stress and failure site of intact and injured myotendinous junction preparations consisting of muscle cells dissected free from surrounding parallel structures but still attached to tendon collagen fibers. These tests show that the breaking stress for intact myotendinous units is 2.7 x 10(5) N/m2, expressed relative to cell cross-sectional area. Failure occurs immediately external to the junction membrane between the cell membrane and lamina densa of the basement membrane. Site and stress at failure are independent of strain and strain rate over a biologically relevant range. Breaking stress in the plane of the membrane, corrected for membrane folding, is 1.2 X 10(4) N/m2. This value is not significantly greater than stress at maximum isometric tension for these cells at these sarcomere lengths. After compression injury, cells fail within the compression site at significantly lower stress (1.9 X 10(5) N/m2). These findings suggest that, in muscle strain injuries that occur under conditions simulated here, failure occurs at myotendinous junctions unless the muscle has suffered previous compression injury leading to failure within the muscle.


2019 ◽  
Author(s):  
Wataru Yamamoto ◽  
Rafael Yuste

AbstractThe neural code relates the activity of the nervous system to the activity of the muscles to the generation of behavior. To decipher it, it would be ideal to comprehensively measure the activity of the entire nervous system and musculature in a behaving animal. As a step in this direction, we used the cnidarian Hydra vulgaris to explore how physiological and environmental conditions alter the activity of the entire neural and muscle tissue and affect behavior. We used whole-body calcium imaging of neurons and muscle cells and studied the effect of temperature, media osmolarity, nutritional state and body size on body contractions.In mounted Hydra, changes in temperature, nutrition or body size did not have a major effect on neural or muscle activity, or on behavior. But changes in media osmolarity altered body contractions, increasing them in hipo-osmolar media solutions and decreasing them in hyperosmolar media. Similar effects were seen in ectodermal, but not in endodermal muscle. Osmolarity also bidirectionally changed the activity of contraction bursts neurons, but not of rhythmic potential neurons.These findings show osmolarity-dependent changes in neuronal activity, muscle activity, and contractions, consistent with the hypothesis that contraction burst neurons respond to media osmolarity, activating ectodermal muscle to generate contraction bursts. This dedicated circuit could serve as an excretory system to prevent osmotic injury. This work demonstrates the feasibility of studying the entire neuronal and muscle activity of behaving animals.Significance StatementWe imaged whole-body muscle and neuronal activity in Hydra in response to different physiological and environmental conditions. Osmolarity bidirectionally altered Hydra contractile behavior. These changes were accompanied by corresponding changes in the activity of one neuronal circuit and one set of muscles. This work is a step toward comprehensive deciphering of the mechanisms of animal behavior by measuring the activity of all neurons and muscle cells.


2010 ◽  
Vol 67 (12) ◽  
pp. 977-982 ◽  
Author(s):  
Aleksandra Mladenovic-Mihailovic ◽  
Zorica Mladenovic-Bogdanovic ◽  
Predrag Mitrovic ◽  
Irena Tanaskovic ◽  
Slavica Usaj-Knezevic ◽  
...  

Background/Aim. Myomas of the uterus, the most common benign tumors, have been studied for decades from the aspects of different basic and clinical disciplines. Despite this fact, their pathogenesis is still poorly understood. The aim of this study was to determine immunocytochemical characteristics of smooth muscle cells and connective tissue components of submucosal myomas of the uterus. Method. During the course of this study, 25 samples of submucosal myomas of the uterus were analyzed, all of them obtained during the surgery, after abdominal histerctomy by Aldridge. The samples were fixed in 4% formalin and embedded in paraffin. Sections of 5 ?m thickness were stained immunocytochemically using the DAKO LSAB+/HRP technique to identify ?- smooth muscle actin (?-SMA), vimentin, desmin, CD34, CD45, CD68 and PCNA (DAKO specification). Results. Our results suggest that submucosal myomas of the uterus are build-up of smooth muscle cells which are immunoreactive to ?-SMA and desmin, but also to a certain number of smooth muscle cells which are immunoreactive to ?-SMA and vimentin. Some of vimentin-immunoreactive cells also show an immunoreactivity of PCNA. In the build-up of connective stroma CD34-immunoreactive fibroblasts and neovascular formations are also present. By examining the distribution of CD45 antigen, at all the analyzed samples we observed a weak reaction. Conclusion. Submucosal myomas of the uterus are made-up of smooth muscle cells of the highly differentiated contractile phenotype (?-SMA- and desminimmunoreactivity), as well as smooth muscle cell of the synthetic phenotype which proliferate (?-SMA-, vimentin- and PCNA-immunoreactivity). In submucosal myoma of the uterus there is a significant presence of connective tissue as a result of synthetic activity of fibroblasts, which clearly differ in their immunocytochemical characteristics from smooth muscle cells of the synthetic phenotype.


2021 ◽  
Vol 42 (Supplement_1) ◽  
Author(s):  
O V Sidorovich ◽  
S Y U Elizarova ◽  
A V Khizhnyak ◽  
N A Kuznetsova ◽  
E E Prosova

Abstract   Within the framework of the research into pathological conditions and syndromes associated with undifferentiated connective tissue dysplasia (UCTD), an emphasis needs to be placed on the changes in heart rhythm. In puberty, the severity of neurovegetative disorders caused by the presence of UCTD might increase manifold. The features of heart rate variability (HRV) in pubertal children against the background of UCTD have been studied insufficiently and require more detailed analysis. This study aims to assess heart rate variability and tone of the autonomic nervous system (ANS) in puberty-aged children with UCTD. Two groups of children were examined, with methods including electrocardiography and cardiointervalography. The main group consisted of 36 puberty-aged children with UCTD, the control group consisted of 30 healthy children. ANS tone was assessed based on the HRV. In the control group of children aged 11, the value of variation range (VR) was 0.18±0.4, mode amplitude (MA) 35.2±2.4, stress index (IN) 72.8±4.3, which corresponds to the state of vegetative balance. As the puberty progresses, the state of eutonia is replaced by the activation of the sympathetic division of the ANS, which becomes most pronounced at the age of 13 years. In the control group of children aged 13, the value of VR was 0.08±0.02, MA 61.7±2.1, SI 210.6±8.6, which corresponds to moderate sympathicotonia. By the end of puberty, in healthy children, the severity of sympathetic activation begins to decrease, and at the age of 15 years, vegetative balance is again observed. However, this pattern is violated in children with UCTD. Upon entering puberty, moderate activation of the sympathetic division of the ANS is already observed in children with UCTD. At the age of 11 years in this group, the value of VR is 0.06±0.02, MA 72.4±3.1, SI 211.2±8.6. At the age of 13, pronounced sympathicotonia is observed, which is confirmed by the values of VR - 0.04±0.01, MA 80.2±4.3 and SI 34.3±14.7. By the end of puberty in children with UCTD, in contrast to the control group, the analyzed parameters indicate not an equilibrium of the ANS, but the predominance of parasympathetic activation. The research provides an insight into heart rate variability in puberty-aged children with UCTD. It was established that healthy children enter puberty in a state of equilibrium of the autonomic nervous system, which in the middle of puberty is replaced by moderate sympathicotonia, and then returns to its original values. Children with the presence of UCTD enter puberty with moderately pronounced sympathicotonia, which gradually increases to pronounced values and is replaced by moderate vagotonia. FUNDunding Acknowledgement Type of funding sources: None.


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