scholarly journals Analysis of the Kinesiology of Skate Skiing and Roller Skiing

2018 ◽  
Vol 3 (70) ◽  
Author(s):  
Jiří Suchý ◽  
Bronislav Kračmar
Keyword(s):  
Frontal Plane ◽  
Gluteus Medius ◽  
Shoulder Girdle ◽  
Lower Limbs ◽  
Bipedal Walking ◽  
Free Form ◽  
Control Group ◽  
Step Cycle ◽  
Cross Country

The peak of human locomotive ontogenesis is unsupported bipedal walking. We can assume that the patterns for locomotion in sport correspond to the patterns for walking. In this study the coordination of motion in six selected key muscle groups and one control group was observed during the use of cross-country skis with ski-poles on snow (free form, skating), and compared with the coordination using roller skis with poles on asphalt. The comparison was carried out skating up a slight slope. Intraindividual analysis of these forms of locomotion was based on surface electromyography (EMG) synchronized with digital video recorded in vivo on site. The data acquired were evaluated by calculating the area under the EMG curve recorded for each muscle under observation. The probability values acquired in this way roughly show the activation and work of the monitored muscle. An ordering of local maximums within a given step cycle was established in order to judge the coordination of motion. The measured data confirmed the phenomenon of triple extension in the lower limbs as well as the phenomenon of pelvic stabilisation in the frontal plane in the single-support position. This stabilisation is ensured by the musculus gluteus medius, which was the only muscle measured to show a different ordering of local EMG curve maximums (timing) when comparing the whole cycle of skiing locomotion on asphalt and on snow. The peaks of activity for this muscle were localised outside the activity peaks of the musculus latissimus dorsi, which is considered the deciding muscle for locomotion realised through the shoulder girdle, but which also performs a stabilising function. Thus both muscles alternate in ensuring stability. The results of the pilot study described demonstrate sufficient kinesiological correspondence between locomotion on skis and on roller skis with poles to confirm the suitability of regular use of roller skis as a specific training instrument for skiing.Keywords: human locomotion, electromyography, skating on cross-country skis and on roller skis.

scholarly journals Sialic Acid and Sialylated Oligosaccharide Supplementation during Lactation Improves Learning and Memory in Rats

Nutrients ◽  
2018 ◽  
Vol 10 (10) ◽  
pp. 1519 ◽  
Author(s):  
Elena Oliveros ◽  
Enrique Vázquez ◽  
Alejandro Barranco ◽  
María Ramírez ◽  
Agnes Gruart ◽  
...  
Keyword(s):  
Cognitive Abilities ◽  
Behavioral Assessment ◽  
Long Term Potentiation ◽  
Cognitive Outcomes ◽  
Free Form ◽  
Control Group ◽  
Adult Rats ◽  
Acetylneuraminic Acid ◽  
One Year

Sialic acids (Sia) are postulated to improve cognitive abilities. This study evaluated Sia effects on rat behavior when administered in a free form as N-acetylneuraminic acid (Neu5Ac) or conjugated as 6′-sialyllactose (6′-SL). Rat milk contains Sia, which peaks at Postnatal Day 9 and drops to a minimum by Day 15. To bypass this Sia peak, a cohort of foster mothers was used to raise the experimental pups. A group of pups received a daily oral supplementation of Neu5Ac to mimic the amount naturally present in rat milk, and another group received the same molar amount of Sia as 6′-SL. The control group received water. After weaning, rats were submitted to behavioral evaluation. One year later, behavior was re-evaluated, and in vivo long-term potentiation (LTP) was performed. Brain samples were collected and analyzed at both ages. Adult rats who received Sia performed significantly better in the behavioral assessment and showed an enhanced LTP compared to controls. Within Sia groups, 6′-SL rats showed better scores in some cognitive outcomes compared to Neu5Ac rats. At weaning, an effect on polysialylated-neural cell adhesion molecule (PSA-NCAM) levels in the frontal cortex was only observed in 6′-SL fed rats. Providing Sia during lactation, especially as 6′-SL, improves memory and LTP in adult rats.

NO ASSOCIATION AMONG GLUTEUS MEDIUS ACTIVITY, HIP ABDUCTION STRENGTH, AND KINEMATIC VARIABLES DURING SINGLE-LEG SQUAT IN YOUNG WOMEN WITH CHRONIC NONSPECIFIC LOW BACK PAIN

2020 ◽  
pp. 2050016
Author(s):  
Leonardo Intelangelo ◽  
Diego Bordachar ◽  
Cristian Mendoza ◽  
Nicolás Bevacqua ◽  
Alexandre Carvalho Barbosa
Keyword(s):  
Low Back Pain ◽  
Back Pain ◽  
Young Women ◽  
Frontal Plane ◽  
Gluteus Medius ◽  
Control Group ◽  
Electromyographic Activity ◽  
Adult Women ◽  
Low Back ◽  
Single Leg Squat

Background: Chronic nonspecific low back pain (CNSLBP) is the leading cause of long-term pain and disability. There is evidence suggesting a relationship between CNSLBP in adult women and altered hip kinematics and gluteus medius (GM) muscle function. However, this association has been less studied in young women. Objective: To assess the association between lower limb and pelvis kinematics in the frontal plane, and GM strength and electromyographic activity in young women with CNSLBP compared with an age-matched control group of asymptomatic women. Methods: In this cross-sectional study, 32 young women with CNSLBP ([Formula: see text] months of pain; Oswestry index range: 21–40%) and 20 healthy age-matched women were included. The frontal plane projection angle (FPPA) and contralateral pelvis drop (CPD) at the endpoint of the single-leg squat (SLS) test were measured through photogrammetry. Mean GM muscle activity during the SLS and peak isometric GM strength was measured using surface electromyography (sEMG) and hand-held dynamometry, respectively. Results: The Hotelling’s trace showed no significant differences between groups when the variables were considered as a composite ([Formula: see text]; [Formula: see text]). Also, the univariate results showed no individual differences between groups considering each variable separately. Conclusions: The results showed no association between CNSLBP, hip and pelvis kinematics, and GM strength and activity in young women.

scholarly journals Polymethylmethacrylatebased antibacterial coating in vitro and in vivo

2019 ◽  
Vol 62 (6) ◽  
pp. 725-731
Author(s):  
P. A. Volotovski ◽  
D. V. Tapalski ◽  
A. A. Sitnik ◽  
A. I. Kozlova ◽  
M. A. Gerasimenko
Keyword(s):  
Antibacterial Activity ◽  
Recurrence Rate ◽  
Main Group ◽  
Lower Limbs ◽  
Control Group ◽  
Antibacterial Coating ◽  
Broth Microdilution Method ◽  
Infection Recurrence

Nowadays, the infection recurrence rate in osteomyelitis is still high. New hardware not only allowing one to stabilize bone fragments, but also having antibacterial activity seems to be an extremely useful and promising task. The goal of the study was to assess the effectiveness of use of an antibacterial coating based on polymethylmethacrylate cement in experiment and in infected nonunions of long tubular bones of the lower limbs. Bone cement-based coatings impregnated with antibiotics were formed on titanium plates. A plate rinse was carried out; antibiotic concentrations in the rinsed solutions were estimated by a serial broth microdilution method. The antibacterial activity of control and rinsed samples against the antibiotic-sensitive and multiple-antibiotic-resistant Staphylococcus aureus and Pseudomonas aeruginosa strains was estimated by a bilayer agar method. Clinical part. The study included 70 patients divided into 2 groups: osteosynthesis with antibacterial-coated interlocking nail (40 patients, main group) and osteosynthesis with an external fixation device (30 patients, control group) comparable in age, sex and disease duration. The effectiveness of the antibacterial coating was analyzed by the duration of systemic use of antibiotics and infection recurrence rate. The concentrations of meropenem and phosphomycin in the rinsed solutions obtained at one-fold and two-fold treatments were sufficient to suppress the growth of control strains. Vancomycin-containing samples possessed sufficient antibacterial activity against both methicillin-sensitive (MSSA) and methicillin-resistant (MRSA) S. aureus strains, double rinse of the samples eliminated their bactericidal properties. The duration of systemic antibacterial therapy in the main group was statistically significantly lower than in the control group (U = 77.5, p < 0.001), and in the main group the infection recurrence rate was lower than 32.5 % vs. 86.7 % (χ2 = 20.39, p < 0.001). The PMMA-based coating impregnated with phosphomycin, meropenem or vancomycin possesses sufficient and long-lasting antibacterial activity, mainly against antibiotic-sensitive strains. An adequate use of such a coating in clinical practice allows one to obtain the desired result of treatment.

Periodic Curcumin Monoglucuronide Injections Ameliorate Structural Osteoarthritis Changes in Rats with Destabilized Medial Meniscus

2020 ◽  
Author(s):  
Akihiro Nakahata ◽  
Akira Ito ◽  
Ryo Nakahara ◽  
Atsuhiro Kishimoto ◽  
Atsushi Imaizumi ◽  
...  
Keyword(s):  
Articular Cartilage ◽  
Medial Meniscus ◽  
Plate Thickness ◽  
Immunohistochemical Analysis ◽  
Water Soluble ◽  
Free Form ◽  
Control Group ◽  
Micro Computed Tomography ◽  
Osteophyte Formation

Abstract Background: Curcumin has anti-inflammatory effects. However, curcumin is poorly water-soluble, and when administered orally, formscurcumin conjugates with poor efficacy.Curcumin monoglucuronide (TBP1901) is highly water-soluble and can existinthe free-form in a greater proportion than curcumin in vivo. This study aimed to evaluate the effectiveness of intra-articular TBP1901 injections fora rat model of osteoarthritis (OA).Methods: Sixty-four male Wistar rats (12weeks old) that had receivedthe destabilized medial meniscus(DMM) surgery, were randomly separatedinto the TBP1901 injectionandthe saline solution injection (control) group. They were sacrificedat 1, 2, 6, or 10weeks postoperatively(n = 8 for each). The TBP1901 (30mg/mL) andsaline solutionof 50μLwere administered to the knee joint through the patella tendon twice a week for the rats sacrificedat1 and 2weeks or once a week for at6 and 10weeks. The OA changes were evaluated by micro-computed tomography (micro-CT), histology, and immunohistochemical analysis.Results:Curcumin fluorescence was confirmed in the articular cartilageand synovium of rats with TBP1901 injections at all observation periods.The TBP1901injections significantly reducedthe synovial inflammation at 1 and 2 weeks and the expression of TNFα in thetibialarticular cartilage at 6 weeks postoperatively.Moreover, TBP1901 injections ameliorated the articular cartilage structure, the subchondral bone (SB) plate thickness, and perforations from 6 to 10 weeks.As a result, there were significant differencesbetween groups in OA scores, SB plate thickness, and perforations at 10 weeks postoperatively.In addition, osteophyte formation in the TBP1901group was significantly suppressed after 10 weeks.Conclusion: This study reports the first evidence that TBP1901 injections suppress inflammation and osteophyte formation, and ameliorate the articular cartilage and SB pathologies by absorption in the articular cartilage and synovium in a rat DMM model.Therefore, intra-articular injections of TBP1901may be effective in improving OA pathology.

Facilitated migration of cells from a transected peripheral nerve over collagen fibers: in vivo observations

1989 ◽  
Vol 47 ◽  
pp. 888-889
Author(s):  
Arthur J. Wasserman ◽  
Azam Rizvi ◽  
George Zazanis ◽  
Frederick H. Silver
Keyword(s):  
Sciatic Nerve ◽  
Peripheral Nerve ◽  
Collagen Gel ◽  
Collagen Fibers ◽  
Control Group ◽  
Guide Tube ◽  
Sprague Dawley ◽  
Silicone Tube ◽  
Thin Sections

In cases of peripheral nerve damage the gap between proximal and distal stumps can be closed by suturing the ends together, using a nerve graft, or by nerve tubulization. Suturing allows regeneration but does not prevent formation of painful neuromas which adhere to adjacent tissues. Autografts are not reported to be as good as tubulization and require a second surgical site with additional risks and complications. Tubulization involves implanting a nerve guide tube that will provide a stable environment for axon proliferation while simultaneously preventing formation of fibrous scar tissue. Supplementing tubes with a collagen gel or collagen plus extracellular matrix factors is reported to increase axon proliferation when compared to controls. But there is no information regarding the use of collagen fibers to guide nerve cell migration through a tube. This communication reports ultrastructural observations on rat sciatic nerve regeneration through a silicone nerve stent containing crosslinked collagen fibers.Collagen fibers were prepared as described previously. The fibers were threaded through a silicone tube to form a central plug. One cm segments of sciatic nerve were excised from Sprague Dawley rats. A control group of rats received a silicone tube implant without collagen while an experimental group received the silicone tube containing a collagen fiber plug. At 4 and 6 weeks postoperatively, the implants were removed and fixed in 2.5% glutaraldehyde buffered by 0.1 M cacodylate containing 1.5 mM CaCl2 and balanced by 0.1 M sucrose. The explants were post-fixed in 1% OSO4, block stained in 1% uranyl acetate, dehydrated and embedded in Epon. Axons were counted on montages prepared at a total magnification of 1700x. Montages were viewed through a dissecting microscope. Thin sections were sampled from the proximal, middle and distal regions of regenerating sciatic plugs.

In-vitro- und In-vivo-Wirkung von Schilddrüsenhormon auf das Wachstum von Neuroblastomzellen

1990 ◽  
Vol 29 (03) ◽  
pp. 120-124
Author(s):  
R. P. Baum ◽  
E. Rohrbach ◽  
G. Hör ◽  
B. Kornhuber ◽  
E. Busse
Keyword(s):  
Cell Differentiation ◽  
Neuroblastoma Cells ◽  
Control Group ◽  
Initial Value ◽  
Initial Rise ◽  
Biphasic Effect ◽  
Contrast Microscopy ◽  
Morphological Sign

The effect of triiodothyronine (T3) on the differentiation of cultured neuroblastoma (NB) cells was studied after 9 days of treatment with a dose of 10-4 M/106 cells per day. Using phase contrast microscopy, 30-50% of NB cells showed formation of neurites as a morphological sign of cellular differentiation. The initial rise of the mitosis rate was followed by a plateau. Changes in cyclic nucleotide content, in the triphosphates and in the activity of the enzyme ornithine decarboxylase (ODC) were assessed in 2 human and 2 murine cell lines to serve as biochemical parameters of the cell differentiation induced by T3. Whereas the cAMP level increased significantly (3 to 7 fold compared with its initial value), the cGMP value dropped to 30 to 50% of that of the control group. ATP and GTP increased about 200%, the ODC showed a decrease of about 50%. The present studies show a biphasic effect of T3 on neuroblastoma cells: the initial rise of mitotic activity is followed by increased cell differentiation starting from day 4 of the treatment.

Platelet Aggregation in Diabetes Mellitus and the Effect of Insulin in Vivo on Aggregation

1972 ◽  
Vol 27 (01) ◽  
pp. 114-120 ◽  
Author(s):  
A. A Hassanein ◽  
Th. A El-Garf ◽  
Z El-Baz
Keyword(s):  
Platelet Aggregation ◽  
Rapid Onset ◽  
Control Group ◽  
Diabetic Patients ◽  
Fasting State ◽  
Clotting Time ◽  
Cholesterol Levels ◽  
Platelet Disaggregation ◽  
Aggregation And Disaggregation

SummaryADP-induced platelet aggregation and calcium-induced platelet aggregation tests were studied in 14 diabetic patients in the fasting state and half an hour after an intravenous injection of 0.1 unit insulin/kg body weight. Platelet disaggregation was significantly diminished as compared to a normal control group, and their results were negatively correlated with the corresponding serum cholesterol levels. Insulin caused significant diminution in the ADP-induced platelet aggregation as a result of rapid onset of aggregation and disaggregation. There was also a significant increase in platelet disaggregation. In the calcium-induced platelet aggregation test, there was a significant shortening of the aggregation time, its duration, and the clotting time. The optical density fall due to platelet aggregation showed a significant increase. Insulin may have a role in correcting platelet disaggregation possibly through improvement in the intracellular enzymatic activity.

Consumption of Hageman Factor Activity in the Generalized Shwartzman Reaction Induced by Liquoid

1970 ◽  
Vol 23 (02) ◽  
pp. 386-404 ◽  
Author(s):  
G Müller-Berghaus ◽  
H. G Lasch
Keyword(s):  
Partial Thromboplastin Time ◽  
Lethal Dose ◽  
Control Group ◽  
Factor V ◽  
Consumption Coagulopathy ◽  
Factor Activity ◽  
Hageman Factor ◽  
Intravascular Coagulation ◽  
Shwartzman Reaction

SummaryThe role of Hageman factor in triggering intravascular coagulation has been studied in rabbits injected intravenously with Liquoid. Besides changes of coagulation parameters characteristic of consumption coagulopathy (e.g. decrease in platelet counts, fibrinogen levels, factor V activity), a pronounced drop in Hageman factor activity was observed after injection of Liquoid. Likewise, the partial thromboplastin time became prolonged.The activation of Hageman factor in vivo could be prevented by intravenous infusion of lysozyme. Twenty min after starting the lysozyme infusion, the partial thromboplastin time became prolonged from a mean of 29 sec to 108 sec. Animals infused with lysozyme and injected with a lethal dose of Liquoid did not develop a consumption coagulopathy. In the same manner, none of 10 animals treated with lysozyme developed the generalized Shwartzman reaction, whereas in the control group 19 out of 20 animals showed fibrin thrombi in the glomerular capillaries.From the present study it may be concluded that the intravascular coagulation process after intravenous injection of Liquoid is triggered by Hageman factor activation.

Effect of Depolymerized Holothurian Glycosaminoglycan (DHG) on Tissue Factor Pathway Inhibitor: In Vitro and In Vivo Studies

1997 ◽  
Vol 78 (02) ◽  
pp. 864-870 ◽  
Author(s):  
Hideki Nagase ◽  
Kei-ichi Enjyoji ◽  
Yu-ichi Kamikubo ◽  
Keiko T Kitazato ◽  
Kenji Kitazato ◽  
...  
Keyword(s):  
Tissue Factor ◽  
Tissue Factor Pathway Inhibitor ◽  
Factor Xa ◽  
Free Form ◽  
Initial Reaction ◽  
Extrinsic Pathway ◽  
Factor Xa Inhibition ◽  
Tissue Factor Pathway

SummaryDepolymerized holothurian glycosaminoglycan (DHG) is a glycosaminoglycan extracted from the sea cucumber Stichopus japonicusSelenka. In previous studies, we demonstrated that DHG has antithrombotic and anticoagulant activities that are distinguishable from those of heparin and dermatan sulfate. In the present study, we examined the effect of DHG on the tissue factor pathway inhibitor (TFPI), which inhibits the initial reaction of the tissue factor (TF)-mediated coagulation pathway. We first examined the effect of DHG on factor Xa inhibition by TFPI and the inhibition of TF-factor Vila by TFPI-factor Xa in in vitro experiments using human purified proteins. DHG increased the rate of factor Xa inhibition by TFPI, which was abolished either with a synthetic C-terminal peptide or with a synthetic K3 domain peptide of TFPI. In contrast, DHG reduced the rate of TF-factor Vila inhibition by TFPI-factor Xa. Therefore, the effect of DHG on in vitroactivity of TFPI appears to be contradictory. We then examined the effect of DHG on TFPI in cynomolgus monkeys and compared it with that of unfractionated heparin. DHG induced an increase in the circulating level of free-form TFPI in plasma about 20-fold when administered i.v. at 1 mg/kg. The prothrombin time (PT) in monkey plasma after DHG administration was longer than that estimated from the plasma concentrations of DHG. Therefore, free-form TFPI released by DHG seems to play an additive role in the anticoagulant mechanisms of DHG through the extrinsic pathway in vivo. From the results shown in the present work and in previous studies, we conclude that DHG shows anticoagulant activity at various stages of coagulation reactions, i.e., by inhibiting the initial reaction of the extrinsic pathway, by inhibiting the intrinsic Xase, and by inhibiting thrombin.

Overtraining of aerobic physical exercise reduce rats (Rattus norvegicus) memory

2020 ◽  
Vol 14 (1) ◽  
Author(s):  
Ni Made Ridla Parwata
Keyword(s):  
Body Weight ◽  
Physical Exercise ◽  
Rattus Norvegicus ◽  
Research Method ◽  
Male Rat ◽  
Control Group ◽  
Adult Male Rat ◽  
The Subject ◽  
Heavy Training

Overtraining syndrome is a decrease in physical capacity, emotions and immunity due to training that is too often without adequate periods of rest. Overtraining is often experienced by athletes who daily undergo heavy training with short break periods. This research aims to look at the effect of overtraining aerobic physical exercise on memory in mice. The research method was experimental in vivo with the subject of adult male rat (Rattus Norvegicus) Winstar strain aged 8-10 weeks, body weight 200-250 gr. Divided into three groups, namely the control group, aerobic group and overtraining group. The results of memory tests with water E Maze showed an increase in the duration of travel time and the number of animal errors made by the overtraining group (p = 0.003). This study concludes that overtraining aerobic physical exercise can reduce memory in rat hippocampus.

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