Fixation of Light Weight Polypropylene Mesh with n-Butyl-2-cyanocrylate in Pelvic Floor Surgery: Experimental Design Approach in Sheep for Effectiveness Evaluation

Objective. The aim of this study was to find a proper experimental design and to evaluate n-butyl-2-cyanoacrylate (Histoacryl) as a fixation method for a light-weight and large pore PP mesh (Synthetic PP Mesh-1) using the sheep as an animal model.Methods. Posterior vaginal implantation by means of episiotomy was used to implant 8 ewes which were evaluated macroscopically and histologically at 3 months (n=4) and 6 months (n=4) post-surgery. In previous pilot studies anterior vaginal implantation was evaluated, as well as different synthetic mesh materials, sizes and fixation methods (n=1to 3) during three weeks. In all cases a clinical evaluation of the animal was performed.Results. A reduction in the mesh size (Synthetic PP Mesh-1) together with precise application of the surgical glue Histoacryl to fix the mesh yielded significantly better histocompatibility results (P<0.01) compared to larger size or other fixation methods.Conclusion. The combination ofSynthetic PP Mesh-1with Histoacryl offered a high degree of graft integration without vaginal ulceration and a minimal foreign body reaction, being the sheep a proper animal model to test these types of medical devices.

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Ultimate Load Measuring System for Fixation of Soft Tissue to Bone

Foot & Ankle International ◽

10.1177/10711007211040504 ◽

2021 ◽

pp. 107110072110405

Author(s):

Tatsuya Fujii ◽

Makoto Tateura ◽

Masato Ogawa ◽

Satoru Ozeki

Keyword(s):

Animal Model ◽

Experimental Animal ◽

Ultimate Load ◽

Testing Machine ◽

Graft Fixation ◽

Experimental Animal Model ◽

Fixation Method ◽

Lateral Ankle ◽

Fixation Methods ◽

Significant Difference

Background: The initial ultimate load for graft fixation is one of the essential factors in the reconstruction of lateral ankle ligaments. Several anchoring devices have been developed to fix the substitute ligament into the bone. A fair comparison of these fixation methods warrant a reproducible examination system. The purpose of this study was to make an experimental animal model and to compare the initial ultimate loads of 3 graft fixation methods, including the use of EndoButton (EB), interference screw (IFS), and a novel socket anchoring (SA) technique. Methods: Porcine calcaneus bones and 5-mm-wide split bovine Achilles tendons were used as fixation bases and graft materials, respectively. Both ends were ﬁrmly sutured side-by-side, using the circumferential ligation technique as a double-strand substitute that was 45 mm in length. Porcine calcanei with similar characteristics to adult human calcanei were mounted on a tensile testing machine, and substitutes were fixed into bones using the 3 fixation methods. A polyester tape was passed through the tendon loop and connected to a crosshead jig of the testing machine. The initial ultimate loads were measured in 15 specimens for each fixation method to simulate a lateral ankle ligament (LAL) injury. Results: The ultimate loads (ULs) were 223.6 ± 52.7 N for EB, 229.7 ± 39.7 N for SA, and 208.8 ± 65.3 N for IFS. No statistically significant difference was observed among the 3 groups ( P = .571). All failures occurred at the bone–ligament substitute interface. Conclusion: The initial ULs in all 3 fixation methods were sufficient for clinical usage. These values were larger than the UL of the anterior talofibular ligament; however, these were smaller than the UL of the calcaneofibular ligament. Clinical Relevance: In an experimental animal model, ULs for SA, EB, and IFS techniques showed no significant difference. All failures were observed in the fixation site of the calcaneus and were overwhelmingly related to suture fixation failure.

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Biomechanical Evaluation of a New Fixation Method for Stabilization of Sagittal Split Ramus Osteotomy After Mandibular Advancement

Craniomaxillofacial Trauma & Reconstruction Open ◽

10.1177/24727512211019230 ◽

2021 ◽

Vol 6 ◽

pp. 247275122110192

Author(s):

Karel Kuik ◽

Jean Pierre T. F. Ho ◽

Cornelis Klop ◽

Maurits H. T. de Ruiter ◽

Cornelis J. Kleverlaan ◽

...

Keyword(s):

Hybrid Method ◽

In Vitro Study ◽

Mandibular Advancement ◽

Fixation Method ◽

Common Procedure ◽

Sagittal Split Ramus Osteotomy ◽

Fixation Methods ◽

Biomechanical Evaluation ◽

Monocortical Screws

Study Design: Biomechanical in vitro study. Mandibular advancement after sagittal split ramus osteotomy (SSRO) is a common procedure in orthognathic surgery. Several fixation methods are used for stabilization of SSRO. Objective: The aim of this study was to compare a new fixation method (gridplate) with more contemporary applied methods of fixation. Material and Methods: In this study, 50 polyurethane hemimandibles with a prefabricated SSRO were used as specimens. All hemimandibles were advanced by 8 mm and divided into 5 groups with different fixation methods: (A) one 4-hole miniplate with 4 monocortical screws; (B) two 4-hole miniplates with 8 monocortical screws; (C) one 4-hole miniplate with 4 monocortical screws and 1 bicortical screw in the retromolar area (hybrid method); (D) 3 bicortical screws in an inverted-L pattern; and (E) one 8-hole gridplate with 8 monocortical screws. Loads in newtons were recorded at displacements of the mandibular incisive edge at 1 mm, 3 mm and 5 mm. Results: Fixation with 3 bicortical screws and the gridplate presented the most stability, followed by two 4-hole miniplates. Fixation with the hybrid method or the single miniplate showed the least stability. Conclusion: According to the results of this study, the 8-hole gridplate design appears a sufficient fixation method regarding stabilization of SSRO with larger mandibular advancement.

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Single-Macromolecular Level Imaging of a Hydrogel Structure

10.33774/chemrxiv-2021-x1s5k ◽

2021 ◽

Author(s):

Ryuji Kiyama ◽

Takayuki Nonoyama ◽

Sedlacik Tomas ◽

Hiroshi Jinnai ◽

Jian Ping Gong

Keyword(s):

Polymer Network ◽

Mesh Size ◽

Fixation Method ◽

Gel Properties ◽

Cell Scaffolds ◽

Transmission Electron ◽

Hydrogel Network ◽

Network Observation ◽

Surface Network ◽

First Time

Hydrogels are promising materials for several applications, including cell scaffolds and artificial load-bearing substitutes (cartilages, ligaments, tendons, etc.). Direct observation of the nanoscale polymer network of hydrogels is essential in understanding its properties. However, imaging of individual network strands at the molecular level is not achieved yet due to the lack of suitable methods. Herein, for the first time, we developed a novel mineral-staining method and network fixation method for transmission electron microscopy observation to visualize the hydrogel network in its unperturbed conformation with nanometer resolution. Surface network observation indicates that the length of surface dangling chains, which play a major role in friction and wetting, can be estimated from the gel mesh size. Moreover, bulk observations reveals a hierarchical formation mechanism of gel heterogeneity. These observations have the great potential to advance gel science by providing comprehensive perspective that link bulk gel properties with nanoscale.

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Een Onderzoek Naar De Effecten Van Luister- En Leesvaardigheids-Training

Toegepaste Taalwetenschap in Artikelen ◽

10.1075/ttwia.26.02anc ◽

1986 ◽

Vol 26 ◽

pp. 7-17 ◽

Cited By ~ 1

Author(s):

Heiko Anceaux

Keyword(s):

Control Group ◽

Light Weight ◽

Research Project ◽

Ability Test ◽

School Year ◽

Class B ◽

Ability Tests ◽

Listening Ability ◽

Grammar Tests ◽

High Degree

This article discusses the final written results of a research project carried out in a number of first-year forms in three Dutch schools for secondary education. In each of the three schools the research project offered a light-weight extra listening programme in class A, and a light-weight extra reading programme in class B, while the regular programme for French was carried out in class C, which served as a control group. At the end of the school year the pupils' reading and listening ability, grammatical knowledge and vocabulary (receptive as well as productive) were evaluated in classes, and C. The general conclusion is that at the elementary level a light-weight extra listening programme does indeed lead to a high degree of listening ability when compared with the other groups. This holds good to an even slightly greater extent for the light-weight extra reading programme. Moreover, it appears that the extra reading programme also leads to a high degree of listening ability. The control groups who had the greatest amount of grammatical training, do indeed score highest in grammar tests, but this knowledge does not become apparent at all in the ability tests /reading and listening). The results of the vocabulary tests are hardly clear. It is probable that at this level reading promotes the acquisition of a productive vocabulary. In the ability test girls generally score higher than boys.

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Morphologic Characteristics of the Medial Malleolar Fragment based on CT Scan in Ankle Fractures

Foot & Ankle Orthopaedics ◽

10.1177/2473011420s00294 ◽

2020 ◽

Vol 5 (4) ◽

pp. 2473011420S0029

Author(s):

Jun-Beom Kim ◽

Chung-Han An

Keyword(s):

Ct Scan ◽

External Rotation ◽

Ankle Fractures ◽

Fixation Method ◽

P Value ◽

Fixation Methods ◽

Morphologic Characteristics ◽

Type 3

Category: Ankle; Trauma Introduction/Purpose: The aim of this study was to describe and evaluate the morphologic characteristics of the medial malleolar fragment in ankle fractures and suggest the guideline for proper fixation of the fragment Methods: From August 2011 to June 2018, 172 cases were enrolled. There were performed the operation in ankle fractures with a medial malleolar fragment. All cases were divided into three types, based on the transverse fracture line of the medial malleolar by the CT (computed tomography) scan; type 1 was involved in the anterior colliculus, type 2 was the intercollicular groove and type 3 was the posterior colliculus. All cases were classified by Lauge-Hansen classification and compared with the groups statistically. The fixation methods by the groups were reviewed and compared. All cases were analyzed by SPSS 19.0, the p-value was less than 0.05. Results: According to the CT scan, type 1 was 14 cases (8.1%), type 2 was 48 cases (27.9%) and type 3 was 110 cases (63.9%). Based on the Lauge-Hansen classification, SER (supination-external rotation) type was 136 cases(76.4%), PER (pronation-external rotation) was 30 cases(17.4%) and PA(pronation abduction) was 8 cases(4.7%).In SER type, type 1 was 6 cases(4.4%), 2 was 42 cases(30.9%) and 3 was 86 cases(63.2%). In PER type, 1 was 6 cases (20%), 2 was 4 cases (13.3%) and 3 was 20 cases (18.9%). In PA type, 1 was 2 cases (25%), 2 was2 cases (25%) and 3 was 4 cases (50%). The fixation methods were various, such as a tension band wiring, 4.0 cannulated screw, hook plate. Conclusion: The morphology of a medial malleolar fragment based on CT scan in ankle fractures were 3 types. There was common a morphology involved the posterior colliculus, Type 3. We suggest that the operators should choose the proper fixation method by the morphology of the fragment and should be careful to avoid the injury of the posterior tibialis tendon.

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A new small animal model for the study of spine fusion in the sand rat: pilot studies

Laboratory Animals ◽

10.1258/la.2008.008055 ◽

2009 ◽

Vol 43 (3) ◽

pp. 272-277 ◽

Cited By ~ 4

Author(s):

Helen E Gruber ◽

Brian Gordon ◽

Cliff Williams ◽

Jane A Ingram ◽

H James Norton ◽

...

Keyword(s):

Animal Model ◽

Small Animal ◽

Spine Fusion ◽

Small Animal Model ◽

Sand Rat ◽

Pilot Studies

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A Schwarz-Christoffel Method for Generating Two-Dimensional Flow Grids

Journal of Fluids Engineering ◽

10.1115/1.3242487 ◽

1985 ◽

Vol 107 (3) ◽

pp. 330-337 ◽

Cited By ~ 10

Author(s):

K. P. Sridhar ◽

R. T. Davis

Keyword(s):

Internal Flow ◽

Mesh Size ◽

Simple Expression ◽

Two Dimensional ◽

Two Dimensional Flow ◽

Mesh Spacing ◽

Flow Configurations ◽

External Flows ◽

Christoffel Transformation ◽

High Degree

A new coordinate generation technique, developed by Davis for external flows, is extended to allow for accurate grid generation for a variety of complex internal flow configurations. The approach is based on numerical integration of the Schwarz-Christoffel transformation for polygonal surfaces. It is shown to be second-order accurate with mesh size due to analytic treatment of boundary singularities. The method is flexible enough to allow for treatment of severe internal geometries, for a high degree of control of mesh spacing, and for generation of either orthogonal or nonorthogonal grids. In addition, this technique directly provides the two-dimensional incompressible potential flow solution for internal flows, as well as a simple expression for calculating the grid metric coefficients. Sample cases include symmetric and asymmetric channel, diffuser, and cascade flows.

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Distal tibial pilon fractures (AO/OTA type B, and C) treated with the external skeletal and minimal internal fixation method

Vojnosanitetski pregled ◽

10.2298/vsp1309836m ◽

2013 ◽

Vol 70 (9) ◽

pp. 836-841 ◽

Cited By ~ 3

Author(s):

Sasa Milenkovic ◽

Milorad Mitkovic ◽

Ivan Micic ◽

Desimir Mladenovic ◽

Stevo Najman ◽

...

Keyword(s):

Internal Fixation ◽

Ankle Joint ◽

Fixation Method ◽

Universal Method ◽

Type B ◽

Tibial Pilon ◽

Post Surgery ◽

Articular Fractures ◽

Type C ◽

Pilon Fractures

Background/Aim. Distal tibial pilon fractures include extra-articular fractures of the tibial metaphysis and the more severe intra-articular tibial pilon fractures. There is no universal method for treating distal tibial pilon fractures. These fractures are treated by means of open reduction, internal fixation (ORIF) and external skeletal fixation. The high rate of soft-tissue complications associated with primary ORIF of pilon fractures led to the use of external skeletal fixation, with limited internal fixation as an alternative technique for definitive management. The aim of this study was to estimate efficacy of distal tibial pilon fratures treatment using the external skeletal and minimal internal fixation method. Methods. We presented a series of 31 operated patients with tibial pilon fractures. The patients were operated on using the method of external skeletal fixation with a minimal internal fixation. According to the AO/OTA classification, 17 patients had type B fracture and 14 patients type C fractures. The rigid external skeletal fixation was transformed into a dynamic external skeletal fixation 6 weeks post-surgery. Results. This retrospective study involved 31 patients with tibial pilon fractures, average age 41.81 (from 21 to 60) years. The average follow-up was 21.86 (from 12 to 48) months. The percentage of union was 90.32%, nonunion 3.22% and malunion 6.45%. The mean to fracture union was 14 (range 12-20) weeks. There were 4 (12.19%) infections around the pins of the external skeletal fixator and one (3.22%) deep infections. The ankle joint arthrosis as a late complication appeared in 4 (12.90%) patients. All arthroses appeared in patients who had type C fractures. The final functional results based on the AOFAS score were excellent in 51.61%, good in 32.25%, average in 12.90% and bad in 3.22% of the patients. Conclusion. External skeletal fixation and minimal internal fixation of distal tibial pilon fractures is a good method for treating all types of inta-articular pilon fractures. In fractures types B and C dynamic external skeletal fixation allows early mobility in the ankle joint.

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Spray drying of pectin obtained from Citrus Sinensis waste

Biointerface Research in Applied Chemistry ◽

10.33263/briac101.825829 ◽

2019 ◽

Vol 10 (1) ◽

pp. 4825-4829

Keyword(s):

Experimental Design ◽

Extraction Process ◽

Laboratory Scale ◽

Acid Extraction ◽

Drying Process ◽

Temperature Ratio ◽

Plant Resources ◽

Gelling Properties ◽

Citrus Waste ◽

High Degree

Polysaccharides are high molecular weight polymers that have functional groups, which can be used as sites to derivate or bind specific ligands. Pectin is a polysaccharide that is obtained from plant resources mainly from citrus plants. It is a widely used product in the food and in the pharmaceutical industry for its thickener, stabilizing and gelling properties. The objective of this work was to establish a pectin drying process obtained by acid hydrolysis from citrus waste by spray dry. An acid extraction process with the dry and ground plant material was used. The influence of the inlet and outlet temperatures on the yield and drying speed was evaluated by an experimental design 32 replicated at the central point. With the best variant, five batches were developed at laboratory scale and one batch at bank scale, evaluating the obtained material by infrared spectroscopy and scanning electron microscopy. The results of experimental design showed that the temperature does not influence significantly the yield, but it does affect the speed of the drying. An input-output temperature ratio of 200/80 ºC was established as the best drying variant. The batches prepared on a laboratory scale showed a yield higher than 85.0% and a drying speed higher than 0.7 L / h. The yield of the batch on a bank scale was 90%. The degree of esterification was 63.5%, indicative of a high degree of methoxylation pectins. The results show that the drying process is adequate to obtain pharmaceutical grade pectin.

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Ege University Faculty of Fisheries Museum (ESFM) cephalopod inventory

Ege Journal of Fisheries and Aquatic Sciences ◽

10.12714/egejfas.37.4.06 ◽

2020 ◽

Vol 37 (4) ◽

pp. 357-361

Author(s):

Alp Salman ◽

Cem Izmirli

Keyword(s):

Aegean Sea ◽

Formalin Fixation ◽

Fixation Method ◽

University Faculty ◽

Marmara Sea ◽

Fixation Methods ◽

Cephalopod Species ◽

Northern Cyprus ◽

The Mediterranean

In this study, cephalopod individuals exemplified in scientific studies from 1988 to 2015 were registered and listed in the Ege University Faculty of Fisheries Museum (ESFM). Cephalopod species examined in the museum were obtained from the Marmara Sea, the Aegean Sea, the Mediterranean and Northern Cyprus waters. In this study, cephalopod individuals exemplified in scientific studies from 1988 to 2015 were registered and listed in the Ege University Faculty of Fisheries Museum (ESFM). These studies showed that Turkey seas surrounding the 46 species of sepiida orders from 58 pieces, the orders in Sepiolida 230, Teuthida orders of 106 pieces and order Octopoda total 146 storage in a jar. As a result of this study surrounding Turkey seas it has been identified 46 species of cephalopods. The cephalopod types found in the museum were first cleaned and fixed to the jars using the formalin fixation method, which is the most suitable of the 4 known fixation methods, and then the necessary information regarding the sampling was labeled on the jars and the ESFM museum registration was performed.

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