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Miho Sato - One of the best experts on this subject based on the ideXlab platform.
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evaluation of surgical strategy based on the intraoperative superior oblique tendon Traction Test
PLOS ONE, 2016Co-Authors: Miwa Komori, Hiroko Suzuki, Akiko Hikoya, Mayu Sawada, Yoshihiro Hotta, Miho SatoAbstract:PURPOSE To clarify the efficacy of a surgical strategy based on the superior oblique tendon Traction Test. METHODS A retrospective chart review was performed between January 2002 and June 2015. During that period, a single inferior oblique muscle (IO) myectomy and a combined IO myectomy and superior oblique muscle (SO) tuck procedure were performed based on SO tendon looseness as revealed by a Traction Test. The surgical effects of both procedures and the number of operations were analyzed. RESULTS Sixty-five cases were retrieved. Seventy-four surgeries were required. The IO myectomy and simultaneous groups included 48 and 17 cases, respectively. Pre-operative vertical deviation was significantly lower in the IO myectomy (11.8 prism diopters) than in the simultaneous (27.2 prism diopters; Mann-Whitney U-Test, P < 0.001) group. The mean induced changes were 9.4 prism diopters and 21.6 prism diopters in the IO myectomy and simultaneous groups, respectively, and the postoperative vertical deviation was not significantly different. On average, 1.13 and 1.18 surgeries per patient were performed in the IO myectomy and simultaneous groups, respectively. CONCLUSION The simultaneous surgery of inferior oblique myectomy and superior oblique tuck is safe and effective for treating large angle of congenital/idiopathic superior oblique palsy with a lax superior oblique tendon, as determined by the Traction Test.
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magnetic resonance imaging and tendon anomaly associated with congenital superior oblique palsy
American Journal of Ophthalmology, 1999Co-Authors: Miho SatoAbstract:Abstract Purpose: To assess the relationship between tendon anomalies and the volume of the superior oblique muscle in patients with congenital unilateral superior oblique palsy. Methods: Thirty-three patients with unilateral congenital superior oblique palsy were enrolled. Coronal, cross-sectional magnetic resonance imaging scans of the superior oblique muscle were obtained, and the volume of the paretic superior oblique muscle belly was calculated as a percentage of the superior oblique muscle belly on the normal side. The percentage volume of the affected superior oblique muscle was compared retrospectively with the angle of the vertical deviation in the primary position, the tendon looseness determined by a Traction Test, and other intraoperative findings. Results: When a tendon was loose, the volume of its muscle belly was significantly smaller than the belly of muscles with a normal taut tendon (Mann-Whitney U Test, P = .0005). The average vertical deviation of patients assessed to have loose tendons was 4.80 prism diopters, and the deviation in patients with normal tendons was 9.90 prism diopters. The mean vertical deviation of patients with atrophic muscle belly on magnetic resonance imaging was 18.1 prism diopters, and that with normal muscle structure was 10.1 prism diopters. The cases with loose tendon as determined by the Traction Test after administration of general anesthesia and the cases with atrophic muscle belly had significantly larger vertical deviation in the primary position than the cases with normal tendons and muscles. (Mann-Whitney U Test, P = .01 and .0196, respectively). Conclusions: The Traction Test is sensitive enough to detect anomalies of the superior oblique tendons. Anomalous superior oblique tendons are nearly always associated with attenuated superior oblique muscle and this information provides us with an explanation for the phenomenon of laxity of the superior oblique tendon.
Nazanin Namjo - One of the best experts on this subject based on the ideXlab platform.
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muscle relaxant activity of elaeagnus angustifolia l fruit seeds in mice
Journal of Ethnopharmacology, 2003Co-Authors: Hossein Hosseinzadeh, Mohammad Ramezani, Nazanin NamjoAbstract:Abstract Muscle relaxant effect of Elaeagnus angustifolia L. (Elaeagnaceae) fruit seeds was studied in mice using Traction Test. The aqueous and ethanolic extracts (i.p) induced a muscle relaxant effect in a dose dependent manner as effective as diazepam (1 mg/kg). The aqueous extract was partitioned with methanol–chloroform (MeCh) and n-butanol (Bu.) saturated with water. The MeCh and Bu. fractions did not show activity. Preliminary phytochemical Tests showed that the extract contains flavonoid. The results suggested that E. angustifolia fruit seeds exerted muscle relaxant activity via flavonoid component(s).
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Muscle relaxant activity of Elaeagnus angustifolia L. fruit seeds in mice.
Journal of ethnopharmacology, 2003Co-Authors: Hossein Hosseinzadeh, Mohammad Ramezani, Nazanin NamjoAbstract:Muscle relaxant effect of Elaeagnus angustifolia L. (Elaeagnaceae) fruit seeds was studied in mice using Traction Test. The aqueous and ethanolic extracts (i.p) induced a muscle relaxant effect in a dose dependent manner as effective as diazepam (1 mg/kg). The aqueous extract was partitioned with methanol-chloroform (MeCh) and n-butanol (Bu.) saturated with water. The MeCh and Bu. fractions did not show activity. Preliminary phytochemical Tests showed that the extract contains flavonoid. The results suggested that E. angustifolia fruit seeds exerted muscle relaxant activity via flavonoid component(s).
Stefano Vidoli - One of the best experts on this subject based on the ideXlab platform.
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Coupling damage and plasticity for a phase-field regularisation of brittle, cohesive and ductile fracture: one-dimensional examples
International Journal of Mechanical Sciences, 2017Co-Authors: Roberto Alessi, Jean-jacques Marigo, Corrado Maurini, Stefano VidoliAbstract:Plasticity and damage are two fundamental phenomena in nonlinear solid mechanics associated to the development of inelastic deformations and the reduction of the material stiffness. Alessi et al. [4] have recently shown, through a variational framework, that coupling a gradient-damage model with plasticity can lead to macroscopic behaviours assimilable to ductile and cohesive fracture. Here, we further expand this approach considering specific constitutive functions frequently used in phase-field models of brittle fracture. A numerical solution technique of the coupled elasto-damage-plasticity problem, based on an alternate minimisation algorithm, is proposed and Tested against semi-analytical results. Considering a one-dimensional Traction Test, we illustrate the properties of four different regimes obtained by a suitable tuning of few key constitutive parameters. Namely, depending on the relative yield stresses and softening behaviours of the plasticity and the damage criteria, we obtain macroscopic responses assimilable to (i) brittle fracturèfracturè a la Griffith, (ii) cohesive fractures of the Barenblatt or Dugdale type, and (iii) a sort of cohesive fracture including a depinning energy contribution. The comparisons between numerical and analytical results prove the accuracy of the proposed numerical approaches in the considered quasi-static time-discrete setting, but they also emphasise some subtle issues occurring during time-discontinuous evolutions.
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gradient damage models coupled with plasticity variational formulation and main properties
Mechanics of Materials, 2015Co-Authors: Jean-jacques Marigo, Roberto Alessi, Stefano VidoliAbstract:Abstract A variational formulation is proposed for a family of elastic–plastic–damage models within the framework of rate-independent materials. That consists first in defining the total energy which contains, in particular, a gradient damage term and a term which represents the plastic dissipation but depends also on damage. Then, the evolution law is deduced from the principles of irreversibility, stability and energy balance. Accordingly, the plastic dissipation term which appears both in the damage criterion and the plastic yield criterion plays an essential role in the damage–plasticity coupling. Suitable constitutive choices on how the plastic yield stress decreases with damage, allows us to obtain a rich variety of coupled responses. A particular attention is paid on the equations which govern the formation of cohesive cracks where the displacement is discontinuous and the plasticity localizes. In the one-dimensional Traction Test where the solution is obtained in a closed form, we show that, because of damage localization, a cohesive crack really appears at the center of the damage zone before the rupture and the associated cohesive law is obtained in closed form in terms of the constitutive parameters. A Finite Element discrete version of the energy functional is used to simulate a two-dimensional Traction Test over a rectangular domain with mixed boundary conditions; again a localized band of plastic strain is generated seemingly independent of the mesh size.
David G. Hunter - One of the best experts on this subject based on the ideXlab platform.
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scleral perforations during routine Traction Test in a patient with osteogenesis imperfecta
Journal of Aapos, 2014Co-Authors: David G. Hunter, Erin M Salcone, Shaden Hamdy, Samir A MelkiAbstract:Osteogenesis imperfecta comprises a rare group of genetic disorders caused by abnormal collagen that results in increased bone fragility and other sequelae. We describe a 37-year-old woman with osteogenesis imperfecta in whom two full-thickness scleral perforations were created by adjacent teeth of 0.5 mm forceps during Traction Testing while undergoing routine strabismus surgery. This case reviews the ocular findings of osteogenesis imperfecta and highlights the potential risk of ocular surgical complications in these patients.
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An adjustable superior oblique tendon spacer with the use of nonabsorbable suture.
Journal of AAPOS : the official publication of the American Association for Pediatric Ophthalmology and Strabismus, 2001Co-Authors: Donny W. Suh, David L. Guyton, David G. HunterAbstract:Abstract Purpose: Philip Knapp described a method, sometimes referred to as the "chicken suture,"of securing a loose nonabsorbable suture to the cut ends of the superior oblique tendon to facilitate future reversal. The purpose of this study is to describe a modification of Knapp's technique to achieve partial, reversible, and intraoperatively adjustable superior oblique weakening. Methods: The superior oblique tendon was exposed, 2 polyester nonabsorbable sutures were placed 4 mm apart, and the tendon was cut. With the use of a slip knot, the cut ends of the tendon were separated by 2 to 8 mm. Tendon separation was adjusted intraoperatively according to the exaggerated Traction Test and, in some cases, fundus torsion. Medical records of all patients who underwent surgery with this technique were reviewed and the outcomes tabulated. Results: Twelve patients (16 eyes) were treated for superior oblique overaction and 3 patients (3 eyes) for Brown syndrome. Follow-up was 2 to 46 months (mean, 17 months). Mean superior oblique overaction improved from +1.3 before surgery to +0.3 after surgery, mean A pattern improved from 20 PD to 2 PD, and fundus intorsion improved from +1.2 to +0.3. In Brown syndrome, the mean elevation in adduction improved from −3.8 to −1.0. One patient from each group developed an overcorrection. None of the patients developed recurrence. The patients with Brown syndrome continued to improve over a 1-year period. Conclusions: The superior oblique tendon suture spacer is effective, intraoperatively adjustable, and technically easier to perform than a silicone expander procedure. This technique should be considered as an alternative for patients requiring superior oblique weakening. (J AAPOS 2001;5:164-71)
Hossein Hosseinzadeh - One of the best experts on this subject based on the ideXlab platform.
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effects of berberis vulgaris fruit extracts and its active component berberine on morphine dependence hypnosis and locomotor activity in mice
2007Co-Authors: Marjan Nassiriasl, Hossein Hosseinzadeh, Seyed Reza MortazaviAbstract:The effects of aqueous and ethanol extracts of Berberis vulgaris (barberry) fruit, as well as its active constituent, berberine, were studied on morphine dependence, hypnotic potentiation, muscle relaxant and locomotor activity in mice. Dependence was induced using subcutaneous injections of morphine (50, 50, 75 mg/kg) daily for 3 days. On day 4, morphine was injected 2 h before the intraperitoneal injection of naloxone (5 mg/kg). The number of episodes of jumping during 30 min after the injection of naloxone was considered as the intensity of the withdrawal syndrome. Berberine (10- 20 mg/kg, i.p.) reduced the number of jumping episodes after the dependence significantly. In other hand, the intraperitoneal injection of both extracts of barberry in different doses decreased the number of jumping episodes significantly during the development of dependence and after dependence. The locomotion activity of animals reduced dose dependently. In the potentiation of pentobarbitone sleep Test, berberine significantly increased sleeping time and decreased latency at the doses of 5 and 10 mg/kg in mice. Also the aqueous (100 mg/kg) and ethanol extracts (100- 200 mg/kg) of barberry increased sleeping time and decreased latency significantly in mice. In the Traction Test, berberine and both extracts couldn’t show muscle relaxant activity. The present data support the hypothesis that the extracts of barberry and berberine have some potential role in potentiation inhibitory neural pathway and decreasing morphine dependence, locomotor activity and inducing hypnosis.
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anticonvulsant sedative and muscle relaxant effects of carbenoxolone in mice
BMC Pharmacology, 2003Co-Authors: Hossein Hosseinzadeh, Marjan Nassiri AslAbstract:Carbenoxolone, as an antiulcer medicine, has some pharmacological properties such as: the inhibition of gap junctional (GJ) intercellular communication. In vitro studies have shown, carbenoxolone to abolish the generation of full or partial ectopic spike generation, by 4-aminopyridine, as well as spontaneous epileptiform activity in CA3 or CA1 regions of the rat hippocampal slices via closing GJ channels. Thus, we considered the possible anticonvulsant effects of carbenoxolone in animal seizure models. ED50 values of diazepam and carbenoxolone in the pentylenetetrazole model were 1.13 mg/kg and 283.3 mg/kg, respectively. In this model, carbenoxolone in doses of 200 and 300 mg/kg prolonged the onset time of seizure and decreased the duration of seizures. In the maximal electroshock model, carbenoxolone in a dose of 400 mg/kg decreased the duration of seizure producing protection against seizure but failing to protect against mortality in comparison with diazepam. In the potentiation of pentobarbitone sleep Test, carbenoxolone significantly increased sleeping time and decreased latency in doses of 100, 200 and 300 mg/kg in mice dose dependently. In the Traction Test, carbenoxolone (400 mg/kg) showed muscle relaxant activity and in the accelerated rotarod Test, carbenoxolone in doses of 200 and 300 mg/kg showed a decline in motor coordination. It can be concluded that carbenoxolone possesses anticonvulsant, muscle relaxant and hypnotic effects, which could contribute to the control of petit mal and grand mal seizures.
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muscle relaxant activity of elaeagnus angustifolia l fruit seeds in mice
Journal of Ethnopharmacology, 2003Co-Authors: Hossein Hosseinzadeh, Mohammad Ramezani, Nazanin NamjoAbstract:Abstract Muscle relaxant effect of Elaeagnus angustifolia L. (Elaeagnaceae) fruit seeds was studied in mice using Traction Test. The aqueous and ethanolic extracts (i.p) induced a muscle relaxant effect in a dose dependent manner as effective as diazepam (1 mg/kg). The aqueous extract was partitioned with methanol–chloroform (MeCh) and n-butanol (Bu.) saturated with water. The MeCh and Bu. fractions did not show activity. Preliminary phytochemical Tests showed that the extract contains flavonoid. The results suggested that E. angustifolia fruit seeds exerted muscle relaxant activity via flavonoid component(s).
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Muscle relaxant activity of Elaeagnus angustifolia L. fruit seeds in mice.
Journal of ethnopharmacology, 2003Co-Authors: Hossein Hosseinzadeh, Mohammad Ramezani, Nazanin NamjoAbstract:Muscle relaxant effect of Elaeagnus angustifolia L. (Elaeagnaceae) fruit seeds was studied in mice using Traction Test. The aqueous and ethanolic extracts (i.p) induced a muscle relaxant effect in a dose dependent manner as effective as diazepam (1 mg/kg). The aqueous extract was partitioned with methanol-chloroform (MeCh) and n-butanol (Bu.) saturated with water. The MeCh and Bu. fractions did not show activity. Preliminary phytochemical Tests showed that the extract contains flavonoid. The results suggested that E. angustifolia fruit seeds exerted muscle relaxant activity via flavonoid component(s).