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1.
Braz. oral res. (Online) ; 33: e079, 2019. graf
Article in English | LILACS | ID: biblio-1019604

ABSTRACT

Abstract Cell therapy associated with guided bone regeneration (GBR) can be used to treat bone defects under challenging conditions such as osteoporosis. This study aimed to evaluate the effect of mesenchymal stem cells (MSCs) in combination with a poly(vinylidene-trifluoroethylene)/barium titanate (PVDF-TrFE/BT) membrane on bone repair in osteoporotic rats. Osteoporosis was induced in female rats by bilateral removal of the ovaries (OVX) or sham surgery (SHAM), and the osteoporotic condition was characterized after 5 months by microtomographic and morphometric analyses. Calvarial defects were created in osteoporotic rats that immediately received the PVDF-TrFE/BT membrane. After 2 weeks, bone marrow-derived MSCs from healthy rats, characterized by the expression of surface markers using flow cytometry, or phosphate-buffered saline (PBS) (Control) were injected into the defects and bone formation was evaluated 4 weeks post-injection by microtomographic, morphometric, and histological analyses. A reduction in the amount of bone tissue in the femurs of OVX compared with SHAM rats confirmed the osteoporotic condition of the experimental model. More bone formation was observed when the defects were injected with MSCs compared to that with PBS. The modification that we are proposing in this study for the classical GBR approach where cells are locally injected after a membrane implantation may be a promising therapeutic strategy to increase bone formation under osteoporotic condition.


Subject(s)
Animals , Female , Polyvinyls/pharmacology , Titanium/pharmacology , Barium Compounds/pharmacology , Guided Tissue Regeneration/methods , Mesenchymal Stem Cells/physiology , Osteogenesis/drug effects , Osteoporosis/physiopathology , Osteoporosis/therapy , Polyvinyls/chemistry , Time Factors , Titanium/chemistry , Bone Regeneration/drug effects , Bone Regeneration/physiology , Ovariectomy , Random Allocation , Bone Density , Reproducibility of Results , Treatment Outcome , Rats, Wistar , Barium Compounds/chemistry , Imaging, Three-Dimensional , Mesenchymal Stem Cells/chemistry , Flow Cytometry
2.
Article in English | WPRIM | ID: wpr-759502

ABSTRACT

BACKGROUND: Compared to an equivalent sized polyvinyl chloride (PVC) double-lumen tube (DLT), a silicone DLT has a shorter endobronchial segment. The aim of this study was to compare the incidence of clinically significant displacement of left-sided PVC and silicone DLTs after a positional change to a lateral position from a supine position and determine its effect on the need for DLT repositioning for successful lung separation in patients undergoing thoracic surgery. METHODS: One hundred eight adult patients requiring one-lung ventilation were randomly divided into group P (PVC DLT, n = 54) and group S (Silicone DLT, n = 54). The position of the DLT was observed before and after lateral positioning to assess the effect of the position change. The incidence of clinically significant displacement (>10 mm) of DLT was compared between the groups. RESULTS: DLTs were clinically significantly displaced in group P (17/48, 35.4%) and group S (18/52, 34.6%) after lateral positioning (p = 0.933). A proximal displacement (31.3% [group P] and 25.0% [group S]) was more common than distal displacement (4.2% [group P] and 9.6% [group S]), with no significant intergroup difference (p = 0.494). After lateral positioning, critical malposition of DLT with bronchial herniation to the right main bronchus was 8.3% (group P) and 7.9% (group S, p = 0.906). CONCLUSION: Left-sided PVC and silicone DLTs produced comparable incidences of clinically significant displacement and, consequently, required similar rates of repositioning for successful lung separation after lateral positioning.


Subject(s)
Adult , Bronchi , Bronchoscopy , Humans , Incidence , Intubation, Intratracheal , Lung , One-Lung Ventilation , Polyvinyl Chloride , Polyvinyls , Posture , Silicon , Silicones , Supine Position , Thoracic Surgery , Thoracic Surgical Procedures
3.
Article in English | WPRIM | ID: wpr-742076

ABSTRACT

PURPOSE: Comparing the accuracy of casts produced from digital workflow to that of casts produced from conventional techniques. MATERIALS AND METHODS: Whole arch alginate (ALG) and polyvinyl siloxane (PVS) impressions were taken with stock trays and custom trays, respectively. The ALG impressions were poured with type III dental stone, while the PVS impressions were poured with type IV dental stone. For the digital workflow, IOS impressions were taken and physical casts were produced by 3D printing. In addition, 3D printed casts were produced from images obtained from a laboratory scanner (LS). For each technique, a total of 10 casts were produced. The accuracies of the whole arch and separated teeth were virtually quantified. RESULTS: Whole arch cast accuracy was more superior for PVS followed by LS, ALG, and IOS. The PVS and ALG groups were inferior in the areas more susceptible to impression material distortion, such as fossae and undercut regions. The LS casts appeared to have generalized errors of minor magnitude influencing primarily the posterior teeth. The IOS casts were considerably more affected at the posterior region. On the contrary, the IOS and LS casts were more superior for single tooth accuracy followed by PVS and ALG. CONCLUSION: For whole arch accuracy, casts produced from IOS were inferior to those produced from PVS and ALG. The inferior outcome of IOS appears to be related to the span of scanning. For single tooth accuracy, IOS showed superior accuracy compared to conventional impressions.


Subject(s)
Jupiter , Polyvinyls , Printing, Three-Dimensional , Siloxanes , Tooth
4.
Article in English | WPRIM | ID: wpr-785816

ABSTRACT

PURPOSE: This study was performed to evaluate the dimensional accuracy of digital dental models constructed from cone-beam computed tomographic (CBCT) scans of polyvinyl siloxane (PVS) impressions and cast scan models.MATERIALS AND METHODS: A pair of PVS impressions was obtained from 20 subjects and scanned using CBCT (resolution, 0.1 mm). A cast scan model was constructed by scanning the gypsum model using a model scanner. After reconstruction of the digital models, the mesio-distal width of each tooth, inter-canine width, and inter-molar width were measured, and the Bolton ratios were calculated and compared. The 2 models were superimposed and the difference between the models was measured using 3-dimensional analysis.RESULTS: The range of mean error between the cast scan model and the CBCT scan model was −0.15 mm to 0.13 mm in the mesio-distal width of the teeth and 0.03 mm to 0.42 mm in the width analysis. The differences in the Bolton ratios between the cast scan models and CBCT scan models were 0.87 (anterior ratio) and 0.72 (overall ratio), with no significant difference (P>0.05). The mean maxillary and mandibular difference when the cast scan model and the CBCT scan model were superimposed was 53 µm.CONCLUSION: There was no statistically significant difference in most of the measurements. The maximum tooth size difference was 0.15 mm, and the average difference in model overlap was 53 µm. Digital models produced by scanning impressions at a high resolution using CBCT can be used in clinical practice.


Subject(s)
Calcium Sulfate , Cone-Beam Computed Tomography , Dental Models , Orthodontics , Polyvinyls , Siloxanes , Tooth
5.
J. appl. oral sci ; 26: e20170077, 2018. tab, graf
Article in English | LILACS, BBO | ID: biblio-893728

ABSTRACT

Abstract Objective Although the effectiveness of chemical cleansing against Candida albicans biofilm has been shown, the effective concentration of denture cleanser tablets has not been studied. The aim of this study was to assess the effect of three denture materials against Candida albicans biofilm and to determine effective concentrations of denture cleanser tablets. Material and methods The surface-roughness of Acron-hi™, QC-20™ and Deflex™ (n=45 per resin) resins was standardized by using a profilometer and their contact angle or surface free energy was calculated. C. albicans biofilm was formed on all three resins and were treated with Polident 3 min™, Corega™ and Fittydent™ cleanser solutions at various concentrations and both resin-biofilm and cleanser-biofilm interest were determined by using a MTT protocol according to the European Committee on Antimicrobial Susceptibility Testing's antifungal susceptibility testing (AFST-EUCAST). Scanning electron microscopy was used to compare the efficacy of different resin materials against C. albicans biofilm. Anticandidal activity and surface free energy statistical parameters were calculated by using 3-way and 1-way ANOVA, respectively (p<0.05). Results Polident 3 min™ and Corega™ tablets significantly inhibited (p<0.05) the proliferation of C. albicans against all denture resins at 27-37 mg/mL. Scanning electron microscopy results indicated that there was no significant difference among resin specimens regarding biofilm formation on dentures. We failed to find a significant relationship between surface free energy and the anticandidal effect of resin types. However, the polarity value of the resins was statistically associated with their anticandidal activity. Conclusions The polarity of the resins, the concentrations of tablets and the chemical content of the cleanser may directly affect C. albicans biofilm formations. Polident 3 min™ and Corega™ tablets should be suggested for patients who use any denture resin types, whereas the Fittydent™ tablet should only be proposed for those who use Deflex™, when two tablets are dropped into 150 mL water.


Subject(s)
Sulfates , Borates , Candida albicans/drug effects , Dental Cements , Denture Bases/microbiology , Denture Cleansers/pharmacology , Antifungal Agents/pharmacology , Polyvinyls , Surface Properties , Tablets , Materials Testing , Candida albicans/isolation & purification , Microscopy, Electron, Scanning , Colony Count, Microbial , Microbial Sensitivity Tests , Analysis of Variance , Biofilms/drug effects , Polymethyl Methacrylate
6.
Article in Korean | WPRIM | ID: wpr-759654

ABSTRACT

The purpose of the study is to compare and analyze the accuracy of digital images obtained from impression and stone model with model scanner and to find out clinical effectiveness. A mandibular left first molar composite resin tooth was made for abutment. Digital models were obtained with a same model scanner(Ceramill Map 400, Amann Girrbach, Austria); (1) Fabricated resin model was scanned(Group C). (2) 10 impressions were taken with putty and polyvinyl siloxane, then were scanned (Group I). (3) Type IV stone was poured in each impressions made in step(2) and 10 stone models were scanned(Group S). 3 dimensional super-impositional program (Geomagic control X, 3D Systems, USA) was used to analyze the STL files. Stone model scan(Group S) showed lower deviation than impression scan(Group I) compared to the control group(P < 0.001). Both Group I and Group S showed signs of expansion in the occlusion surface and margin surface while showing contraction in the axial surface. The deviations were smaller in order of occlusal plane, horizontal plane of margin and axial plane. Within the limited boundary of this study, the digital model obtained from stone model scan showed smaller deviation than the digital model obtained from impression scan.


Subject(s)
Dental Occlusion , Molar , Polyvinyls , Siloxanes , Tooth , Treatment Outcome
7.
Article in English | WPRIM | ID: wpr-758427

ABSTRACT

PURPOSE: Tracheal intubation in a hemorrhagic airway is a difficult procedure because the visibility can be obscured by blood or vomitus. Several devices and methods have been developed to overcome such obstacles, but they are not available at all practical sites. Therefore, this study was conducted to assess the time and success rate of tracheal intubation according to the type of suction tip used in a hemorrhagic airway manikin model. METHODS: This study was a randomized crossover manikin simulation study. We recruited 18 emergency physicians to perform intubation with suction using a Yankauer suction tip and a polyvinyl chloride (PVC) catheter suction tip in a hemorrhagic airway manikin model. We then measured the time and success rate of intubation for each suction tip. RESULTS: The mean intubation time using the Yankauer suction tip was 42.3 seconds, and the mean intubation time using the PVC catheter suction tip was 91.1 seconds (p < 0.001). Two cases of esophageal intubation occurred when the PVC catheter suction tip was used (success rate, 88.9%). In contrast, there was no esophageal intubation when the Yankauer suction tip was used (success rate, 100%) (p=0.217). CONCLUSION: Intubation of a hemorrhagic airway manikin model can be performed in a shorter time when a Yankauer suction tip is used than when a PVC catheter suction tip is used.


Subject(s)
Catheters , Emergencies , Hemorrhage , Intubation , Manikins , Polyvinyl Chloride , Polyvinyls , Suction
8.
Journal of Rhinology ; : 86-90, 2018.
Article in Korean | WPRIM | ID: wpr-718268

ABSTRACT

BACKGROUND AND OBJECTIVES: Although polyvinyl acetate (Merocel®) has been widely used as a packing material after septoplasty, removable nasal packing can increase patient discomfort, local pain, and pressure. Furthermore, the removal of nasal packing has been described as the most uncomfortable and distressing feature associated with septoplasty. The purpose of this study was to investigate the efficacy of polyvinyl acetate with carboxymethyl cellulose sheet (Rhinocel®) nasal packing on patient subjective symptoms, degree of bleeding, hemostasis, and wound healing following septoplasty. SUBJECTS AND METHOD: Forty patients with nasal septum deviation requiring septoplasty were included. Following surgery, one nasal cavity was packed with Rhinocel® and the other one with Merocel®. Patient subjective symptoms while the packing was in situ, hemostatic properties, pain on removal, degree of bleeding on removal, duration of hemostasis after removal, postoperative wound healing, and the cost of the pack were evaluated. RESULTS: Although the two types of packing materials were equally effective in controlling postoperative bleeding after septoplasty, Rhinocel® was significantly more comfortable while in situ and less painful on removal than Merocel®, which was associated with significantly more bleeding on removal and so more time was needed to control hemorrhage. There was no significant difference in postoperative wound healing or pack cost. CONCLUSIONS: The use of Rhinocel® after septoplasty has less discomfort, greater patient satisfaction, and less bleeding on removal with no adverse reactions compared to Merocel® packing. Therefore, Rhinocel® may be a useful packing material after septoplasty.


Subject(s)
Biocompatible Materials , Carboxymethylcellulose Sodium , Hemorrhage , Hemostasis , Humans , Methods , Nasal Cavity , Nasal Septum , Nose , Patient Satisfaction , Polyvinyls , Postoperative Care , Wound Healing
9.
Hosp. Aeronáut. Cent ; 12(1)2017. ilus, tabl, graf
Article in Spanish | LILACS, BINACIS | ID: biblio-911130

ABSTRACT

Introducción: En la década del '80 se iniciaron los conceptos de laparotomía y relaparotomías. La hipertensión intraabdominal, la cirugía del control del daño, la necesidad de reexploración por packing hemostáticos o las colecciones abdominales son las indicaciones para considerar un abdomen abierto y contenido. A lo largo de los años distintos sistemas de contención del abdomen fueron comercializados, reduciendo la mortalidad a 7 %. Objetivos: El problema es la disponibilidad del recurso dado su alto costo en instituciones con bajo presupuesto. El objetivo es analizar la efectividad y seguridad del método propuesto para aplicar en medios donde el recurso no está disponible en su forma comercial. Material y Método: Realizado entre el 01 de enero 2015 y Julio de 2016, 10 pacientes fueron tratados con abdomen abierto y contenido "no comercial ­hand made". Consiste en la aplicación de un film de polivinilo, multifenestrado, ubicado en la cavidad abdominal por debajo del peritoneo. Sobre ésta, una cubierta de poliuretano y gasas que envuelve una sonda tipo K9. Un film adhesivo cubre toda la incisión, aplicándose una presión negativa de 100 a 150 cm de agua. En un solo caso se utilizó el Wittmann Patch. Resultados: En 7 pacientes se hallaron lesiones combinadas. Lesión hepática: 7; 2 presentaban hipertensión intraabdominal con dificultad para el afrontamiento abdominal. Packing pancreático duodenal: 1. Contaminación de la cavidad: 1. La cantidad de exploraciones fue de 9 y de 3 lavados en promedio. Conclusiones: El sistema "no comercial ­hand made" es un método seguro, de bajo costo y con baja de tasa de complicaciones


Introduction: In the decade of the'80 the concept of laparotomy and relaparotomies began. Intra-abdominal hypertension, damage control surgery, need for re ­examination by hemostatic packing or abdominal collections are indications to consider perfoming the open and contained abdomen. Throughout the years different systems of containment of the abdomen were commercialized. reducing mortality to 7%. Objectives: To analyze the effectiveness and safety of the method proposed to be applied where the resource is not available in its commercial way Material and Methods: In the period between January 1, 2015 and July 2016, 10 patients were treated with open abdomen and "non-commercial -hand made" contents. Consists in the application of a multilayer polyvinyl film of 80 microns, located in the abdominal cavity below the peritoneum, surpassing it inwards by 5 cm. A layer of polyurethane and gauze is placed over this layer, which envelops a polyvinyl probe type K9, until it reaches the edge of the wound. An adhesive film covers the whole incision and passes it by 15 cm, while applying a negative pressure of 100 to 150 cm of water. In only one case the technique described by Dietmar Witmann, the Wittmann Patch was used. Results: Combined lesions were found in 7 patients. Liver injury: 7; 2 also presented HIA with difficulty for abdominal coping. Packing Pancreatic duodenal 1. Cavity contamination: 1. The number of scans was 9 and 3 washes on average. Conclusions: The "non -commercial -hand made" system is a safe, low -cost and low complication rate.


Subject(s)
Humans , Polyvinyls , Surgical Procedures, Operative/methods , Abdomen , Surgical Procedures, Operative
10.
Braz. j. med. biol. res ; 49(4): e5106, 2016. graf
Article in English | LILACS | ID: biblio-951668

ABSTRACT

After a traumatic injury to the central nervous system, the distal stumps of axons undergo Wallerian degeneration (WD), an event that comprises cytoskeleton and myelin breakdown, astrocytic gliosis, and overexpression of proteins that inhibit axonal regrowth. By contrast, injured neuronal cell bodies show features characteristic of attempts to initiate the regenerative process of elongating their axons. The main molecular event that leads to WD is an increase in the intracellular calcium concentration, which activates calpains, calcium-dependent proteases that degrade cytoskeleton proteins. The aim of our study was to investigate whether preventing axonal degeneration would impact the survival of retinal ganglion cells (RGCs) after crushing the optic nerve. We observed that male Wistar rats (weighing 200-400 g; n=18) treated with an exogenous calpain inhibitor (20 mM) administered via direct application of the inhibitor embedded within the copolymer resin Evlax immediately following optic nerve crush showed a delay in the onset of WD. This delayed onset was characterized by a decrease in the number of degenerated fibers (P<0.05) and an increase in the number of preserved fibers (P<0.05) 4 days after injury. Additionally, most preserved fibers showed a normal G-ratio. These results indicated that calpain inhibition prevented the degeneration of optic nerve fibers, rescuing axons from the process of axonal degeneration. However, analysis of retinal ganglion cell survival demonstrated no difference between the calpain inhibitor- and vehicle-treated groups, suggesting that although the calpain inhibitor prevented axonal degeneration, it had no effect on RGC survival after optic nerve damage.


Subject(s)
Animals , Male , Polyvinyls/pharmacology , Retinal Ganglion Cells/drug effects , Axons/drug effects , Wallerian Degeneration/drug therapy , Glycoproteins/pharmacology , Optic Nerve Injuries/drug therapy , Axons/pathology , Immunohistochemistry , Cell Survival/drug effects , Treatment Outcome , Cell Death/drug effects , Cell Death/physiology , Rats, Wistar , Optic Nerve Injuries/pathology , Microscopy, Electron, Transmission , Nerve Crush
11.
Braz. oral res. (Online) ; 30(1): e113, 2016. tab, graf
Article in English | LILACS | ID: biblio-951952

ABSTRACT

Abstract The objective of this study was to evaluate the marginal and internal fit of zirconia copings obtained with different digital scanning methods. A human mandibular first molar was set in a typodont with its adjacent and antagonist teeth and prepared for an all-ceramic crown. Digital impressions were made using an intraoral scanner (3Shape). Polyvinyl siloxane impressions and Type IV gypsum models were also obtained and scanned with a benchtop laboratory scanner (3Shape D700). Ten zirconia copings were fabricated for each group using CAD-CAM technology. The marginal and internal fit of the zirconia copings was assessed by the silicone replica technique. Four sections of each replica were obtained, and each section was evaluated at four points: marginal gap (MG), axial wall (AW), axio-occlusal edge (AO) and centro-occlusal wall (CO), using an image analyzing software. The data were submitted to one-way ANOVA and Tukey's test (α = 0.05). They showed statistically significant differences for MG, AO and CO. Regarding MG, intraoral scanning showed lower gap values, whereas gypsum model scanning showed higher gap values. Regarding AO and CO, intraoral digital scanning showed lower gap values. Polyvinyl siloxane impression scanning and gypsum model scanning showed higher gap values and were statistically similar. It can be concluded that intraoral digital scanning provided a lower mean gap value, in comparison with conventional impressions and gypsum casts scanned with a standard benchtop laboratory scanner.


Subject(s)
Humans , Zirconium/chemistry , Dental Impression Technique/instrumentation , Dental Marginal Adaptation , Polyvinyls/chemistry , Reference Values , Siloxanes/chemistry , Image Processing, Computer-Assisted/instrumentation , Materials Testing , Calcium Sulfate/chemistry , Reproducibility of Results , Analysis of Variance , Dental Casting Technique , Dental Prosthesis Design , Computer-Aided Design , Dental Impression Materials/chemistry
12.
Braz. oral res. (Online) ; 30(1): e36, 2016. tab, graf
Article in English | LILACS | ID: biblio-951975

ABSTRACT

Abstract The aim of the study was to evaluate the effect of the incorporation of different fillers on an experimental vinyl polysiloxane (VPS) at two different concentrations, 20% and 40%. Different fillers were added to an experimental VPS. The study was developed in two stages: (i) incorporation of fillers in different concentrations: (a) 20 wt% fillers, and (b) 40 wt%. The fillers were added to experimental VPS and mixed with a speed mixer; (ii) characterization of experimental VPS; after the base paste and catalyst paste were mixed, the experimental VPS was used to make specimens specifically for each test, which were stored at 23°C for 24 hours. The tests were designed according to the specific standardization for the analysis of tensile strength, detail reproduction, Shore A hardness, and elastic recovery. For analysis of filler size pattern, scanning electron microscopy at 1500× magnification was used. The aerosil OX-50 40% (AE), and pure aluminum hydroxide 40% (PAH) groups presented the highest tensile strength and Shore A hardness values. However, those were the only groups that did not present continuous detail reproduction of an intersection of 20 μm line. The elastic recovery was not statistically significant. The undesirable characteristics of VPS (lowest Shore A hardness and tensile strength) were observed when it was added to the composition of acrylic polymer (AP) and fiberglass (FG) in both concentrations, 20% and 40%. In groups AE and PAH, agglomerates of nanofillers were shown in SEM micrography, while the other groups presented different shapes and fillers sizes.


Subject(s)
Polyvinyls/chemistry , Siloxanes/chemistry , Dental Impression Materials/chemistry , Particle Size , Reference Values , Surface Properties , Tensile Strength , Time Factors , Materials Testing , Microscopy, Electron, Scanning , Reproducibility of Results , Analysis of Variance , Elasticity , Hardness Tests
13.
Article in Chinese | WPRIM | ID: wpr-264026

ABSTRACT

<p><b>OBJECTIVE</b>To compare the efficacy, clinical characteristics, safety, injection time and radiation exposure of Onyx embolization using a long-distance injection method and routine injection method for management of dural arteriovenous fistula (DAVF).</p><p><b>METHODS</b>The clinical data were retrospectively analyzed in 59 patients with DAVF treated with Onyx embolization using long-distance injection method (28 patients) and routine injection method (31 patients). The efficacy, safety, injection time and radiation exposure during Onyx embolization were compared between the two injections methods.</p><p><b>RESULTS</b>The average radiation dose exposure to the surgeon per procedure was significantly lower in the long-distance injection group than in the routine group. The injection time (P=0.53), injection volume (P=0.78), number of supply arteries (P=0.80), Cognard types (P=0.67), and effect of embolization (P=0.88) were all similar between the two groups.</p><p><b>CONCLUSION</b>Endovaseular treatment of intracranial DAVF with Onyx embolization using the long-distance injection method is feasible, safe and effective and can reduce the radiation exposure to the surgeon.</p>


Subject(s)
Arteries , Central Nervous System Vascular Malformations , Therapeutics , Dimethyl Sulfoxide , Therapeutic Uses , Embolization, Therapeutic , Humans , Polyvinyls , Therapeutic Uses , Retrospective Studies , Treatment Outcome
14.
Article in English | WPRIM | ID: wpr-124876

ABSTRACT

The author has encountered a 67-year-old man with dural arteriovenous fistula (AVF) presenting as a non-traumatic chronic subdural hematoma (CSDH). This previously healthy patient was hospitalized due to progressive headache with subacute onset. He underwent burr-hole surgery twice for evacuating the left CSDH that was thickest at the posterior temporal area. The operative procedure and finding was not extraordinary, but subdural hematoma slowly progressed for days following the revision surgery. After investigation by super-selective external carotid angiography, a dural AVF found near the transverse-sigmoid sinus was diagnosed. Dural AVF was completely occluded with trans-arterial injecting polyvinyl alchol particles into the petrosquamosal branch of the middle meningeal artery. The patient showed a good neurological outcome with no additional intervention. Brain surgeons have to consider the possibility of dural AVF and perform cerebral angiogram if necessary when they manage the cases that have a spontaneously occurred and repeatedly recurring CSDH.


Subject(s)
Aged , Angiography , Arteriovenous Fistula , Brain , Central Nervous System Vascular Malformations , Headache , Hematoma, Subdural , Hematoma, Subdural, Chronic , Humans , Meningeal Arteries , Polyvinyls , Surgeons , Surgical Procedures, Operative
15.
Article in English | IMSEAR | ID: sea-159457

ABSTRACT

The environment of oral cavity provides a large surface area for the delivery of drugs bypassing the first pass metabolism in the liver. Hence, the oral cavity is being targeted for providing quicker delivery of drugs for immediate action. However, oral delivery system in the form of tablets/ capsules needs modifications in elderly, children, and unconscious patients because of the fear of choking and aspiration. To overcome these problems much research is being undertaken to develop oral bio dissolving films as an alternative to tablets. The objective of the article was to provide an overview of the composition, advantages and disadvantages, and uses of bio dissolving films in the field of medicine and dentistry.


Subject(s)
Administration, Oral , Airway Obstruction/prevention & control , Biofilms/classification , Coated Materials, Biocompatible , Dentistry/drug therapy , Dentistry/therapy , Drug Delivery Systems , Humans , Pharmaceutical Preparations, Dental/administration & dosage , Polyvinyls
16.
IJPR-Iranian Journal of Pharmaceutical Research. 2015; 14 (1): 35-50
in English | IMEMR | ID: emr-154865

ABSTRACT

The present study deals with characterization of dispersions of a poorly water-soluble drug, celecoxib [CLX] in polyvinyl caprolactame-polyvinyl acetate-polyethylene glycol graft copolymer [Soluplus[R] [SOL]] prepared by different techniques. Dispersions of CLX in SOL at different ratios [2:1, 1:1, 1:2, 1:4 and 1:6] were prepared by spray drying, conventional solvent evaporation and melting methods. The solid states of samples were characterized using particle size measurements, optical and scanning electron microscopy, XRPD, DSC and FT-IR. The Gordon-Taylor equation was used to predict the T[g] of samples and the possibility of interaction between CLX and SOL. The solubility and dissolution rate of all samples were determined. Stability of samples was studied at ambient conditions for a period of 12 months. DSC and XRPD analyses confirmed amorphous state of drug in samples. Surprisingly dispersions of CLX:SOL with the ratio of 2:1 and 1:1 showed slower dissolution rate than CLX while other samples showed higher dissolution rate. At 1:2 ratio the spray dried samples exhibited higher dissolution rate than corresponding samples prepared by other methods. However at higher SOL content [1:4 and 1:6], samples prepared by different methods showed similar dissolution profiles. The stability studies showed that there were no remarkable changes in the dissolution profiles and solid state of the drug after 12 months storage at ambient conditions. It was concluded that SOL was a proper carrier to enhance the dissolution rate of CLX. At high SOL ratios the method of preparation of dispersed samples had no effect on dissolution rate, whilst at low SOL content spray drying was more efficient method


Subject(s)
Sulfonamides , Polyethylene Glycols , Polyvinyls
17.
Article in English | WPRIM | ID: wpr-137579

ABSTRACT

OBJECTIVES: This study aims to evaluate the size-dependent toxicity of spherical silver nanoparticles (Ag NPs) to an endemic benthic organism, Glyptotendipes tokunagai. METHODS: Ag nanoparticles of three nominal sizes (50, 100, and 150 nm) capped with polyvinyl pyrrolidone (PVP-Ag NPs) were used. Their physicochemical properties, acute toxicity (48 hours), and bioaccumulation were measured using third instar larvae of G. tokunagai. RESULTS: The aggregation and dissolution of PVP-Ag NPs increased with exposure time and concentration, respectively, particularly for 50 nm PVP-Ag NPs. However, the dissolved concentration of Ag ions was not significant compared with the median lethal concentration value for AgNO3 (3.51 mg/L). The acute toxicity of PVP-Ag NPs was highest for the smallest particles (50 nm), whereas bioaccumulation was greatest for the largest particles (150 nm). However, larger PVP-Ag NPs were absorbed and excreted rapidly, resulting in shorter stays in G. tokunagai than the smaller ones. CONCLUSIONS: The size of PVP-Ag NPs significantly affects their acute toxicity to G. tokunagai. In particular, smaller PVP-Ag NPs have a higher solubility and stay longer in the body of G. tokunagai, resulting in higher toxicity than larger PVP-Ag NPs.


Subject(s)
Chironomidae , Ions , Larva , Nanoparticles , Polyvinyls , Silver , Solubility
18.
Article in English | WPRIM | ID: wpr-137578

ABSTRACT

OBJECTIVES: This study aims to evaluate the size-dependent toxicity of spherical silver nanoparticles (Ag NPs) to an endemic benthic organism, Glyptotendipes tokunagai. METHODS: Ag nanoparticles of three nominal sizes (50, 100, and 150 nm) capped with polyvinyl pyrrolidone (PVP-Ag NPs) were used. Their physicochemical properties, acute toxicity (48 hours), and bioaccumulation were measured using third instar larvae of G. tokunagai. RESULTS: The aggregation and dissolution of PVP-Ag NPs increased with exposure time and concentration, respectively, particularly for 50 nm PVP-Ag NPs. However, the dissolved concentration of Ag ions was not significant compared with the median lethal concentration value for AgNO3 (3.51 mg/L). The acute toxicity of PVP-Ag NPs was highest for the smallest particles (50 nm), whereas bioaccumulation was greatest for the largest particles (150 nm). However, larger PVP-Ag NPs were absorbed and excreted rapidly, resulting in shorter stays in G. tokunagai than the smaller ones. CONCLUSIONS: The size of PVP-Ag NPs significantly affects their acute toxicity to G. tokunagai. In particular, smaller PVP-Ag NPs have a higher solubility and stay longer in the body of G. tokunagai, resulting in higher toxicity than larger PVP-Ag NPs.


Subject(s)
Chironomidae , Ions , Larva , Nanoparticles , Polyvinyls , Silver , Solubility
19.
Int. j. morphol ; 32(4): 1347-1356, Dec. 2014. ilus
Article in English | LILACS | ID: lil-734682

ABSTRACT

Tissue engineering (TE) has become an alternative for auricular reconstruction based on the combination of cells, molecular signals and biomaterials. Scaffolds are biomaterials that provide structural support for cell attachment and subsequent tissue development. Ideally, a scaffold should have characteristics such as biocompatibility and bioactivity to adequate support cell functions. Our purpose was to evaluate biocompatibility of microtic auricular chondrocytes seeded onto a chitosan-polyvinyl alcohol-epichlorohydrin (CS-PVA-ECH) hydrogel to propose this material as a scaffold for tissue engineering application. After being cultured onto CS-PVA-ECH hydrogels, auricular chondrocytes viability was up to 81%. SEM analysis showed cell attachment and extracellular matrix formation that was confirmed by IF detection of type II collagen and elastin, the main constituents of elastic cartilage. Expression of elastic cartilage molecular markers during in vitro expansion and during culture onto hydrogels allowed confirming auricular chondrocyte phenotype. In vivo assay of tissue formation revealed generation of neotissues with similar physical characteristics and protein composition to those found in elastic cartilage. According to our results, biocompatibility of the CS-PVA-ECH hydrogel makes it a suitable scaffold for tissue engineering application aimed to elastic cartilage regeneration.


La ingeniería de tejidos (TE) es una alternativa para la reconstrucción auricular basada en la combinación de células, señales moleculares y biomateriales. Los andamios fabricados con biomateriales brindan un soporte estructural que favorece la adhesión cellular y el desarrollo del tejido. Un andamio debe poseer características como biocompatibilidad y bioactividad para soportar adecuadamente funciones celulares. Nuestro objetivo fue evaluar la biocompatibilidad de condrocitos auriculares de microtia cultivados sobre un hidrogel a base de quitosano-alcohol polivinílico-epiclorhidrina (CS-PVA-ECH) y proponerlo como andamio con aplicaciones en ingeniería de tejidos. La viabilidad de los condrocitos auriculares es superior al 81% después de ser cultivados sobre el hidrogel. El análisis por SEM reveló la unión celular y formación de matriz extracellular sobre el hidrogel; confirmada mediante detección por IF de colágena tipo II y elastina. La expresión de marcadores moleculares durante la expansión in vitro y el cultivo sobre los hidrogeles confirmaron el fenotipo condral. El ensayo de formación de tejido in vivo demostró la generación de neotejidos con características físicas y composición similar al cartílago elástico. Nuestros resultados indican que la biocompatibilidad del hidrogel de CS-PVA-ECH lo hace un andamio adecuado para aplicaciones en ingeniería de tejidos enfocadas a regeneración de cartílago elástico.


Subject(s)
Humans , Chondrocytes/cytology , Tissue Engineering/methods , Chitosan/chemistry , Ear Cartilage/cytology , Polyvinyls/chemistry , Biocompatible Materials , Immunohistochemistry , Cell Culture Techniques , Chondrocytes/metabolism , Hydrogels , Epichlorohydrin/chemistry
20.
Braz. j. oral sci ; 13(2): 118-123, Apr-Jun/2014. tab, graf
Article in English | LILACS | ID: lil-715602

ABSTRACT

AIM: To introduce a modification of the reline impression technique (MRIT), and compare the dimensional changes of impressions obtained by MRIT and by conventional reline impression technique (CRIT). METHODS: An acrylic resin tablet was milled by a CAD-CAM system to simulate three abutments (A, B and C) with different distances among them. The abutments were molded using both impression techniques. For MRIT, before completing the putty silicone polymerization, the relieve procedure was made by compression and it was immediately repositioned to complete the polymerization. Impressions were stored dry at room temperature for different periods (immediately, 1 h, 2 days and 7 days). The distances were obtained by scanning. The differences between the impressions and their respective matrix reference measurements were calculated to determine the dimensional changes. Data were subjected to ANOVA and Tukey's test (p<0.05). RESULTS: For AB and BC distances, there was no statistically significant difference between CRIT and MRIT (p=0.0597 and p=0.2167, respectively). For AC, there was statistically significant difference between the techniques for the immediate storage time (p=0.006). In general, for CRIT the material showed expansion, while for MRIT it showed contraction. CONCLUSIONS: It was verified that the addition silicon impressions obtained by both impression techniques showed dimensional stability, except for the immediate time-point...


Subject(s)
Dental Impression Technique , Dimensional Measurement Accuracy , Research , Dental Impression Materials/analysis , Polyvinyls/therapeutic use , Siloxanes/therapeutic use
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