Polarographic measurement of ascorbate washout in isolated perfused rabbit hearts

International Nuclear Information System (INIS)

Arts, T.; Kuikka, J.T.; Reneman, R.S.; Bassingthwaighte, J.B.

1985-01-01

To study the myocardial washout of ascorbate, the applicability of polarographic detection of ascorbate ions by a platinum electrode (sensitive area 0.03 mm2) was investigated, in both a calibration setup (sampling flow along the electrode: 100 microliter X s-1) and isolated, retrogradely perfused rabbit hearts. In the calibration setup at pH 7.4, the sensitivity of the electrode was 70 microA/mol. This sensitivity increased moderately with increasing pH (13%/unit pH) and increasing sampling flow rate (14% at an increase from 100 to 150 microliter X s-1). In the isolated hearts, ascorbate infused into the aorta was detected in a right ventricular drain by the electrode as well as by the use of 14 C-labeled ascorbate. Both recorded time courses were similar except for a scaling factor dependent on flow velocity. During continuous infusion the arteriovenous difference of ascorbate was 2 +/- 2% (SD), indicating a relatively low consumption of ascorbate by the isolated heart. The authors conclude that polarographic measurement of ascorbate in the coronary effluent of an isolated rabbit heart can be performed on-line and relatively easily

Simultaneous measurement of pO2 and perfusion in the rabbit kidney in vivo.

Science.gov (United States)

O'Connor, Paul M; Anderson, Warwick P; Kett, Michelle M; Evans, Roger G

2007-01-01

Recently, a combined probe has been developed capable of simultaneous measurement of local tissue pO2 (fluorescence oximetry) and microvascular perfusion (laser Doppler flux) within the same local region. The aim of the current study was to test the utility of these combined probes to measure pO2 and perfusion in the kidney. Studies were performed in anesthetized, artificially ventilated rabbits (n=7). Baseline measurements of renal medullary perfusion and pO2 obtained using combined probes (537 +/- 110 units & 28.7 +/- 6.l mmHg, respectively) were indistinguishable from those obtained using independent probes (435 +/- 102 units & 26.9 +/- 6.4 mmHg). Baseline measurements of renal cortical pO2 were also similar between combined (9.7 +/- 1.6 mmHg) and independent probes (9.5 +/- 2.3 mmHg). Baseline levels of cortical perfusion however, were significantly greater when measured using independent probes (1130 +/- 114 units) compared to combined probes (622 +/- 59 units; P pO2 resulting from graded stimulation of the renal nerves were not significantly different when measured using combined probes to those obtained using independent probes. We conclude that combined probes are equally suitable to independent probes for tissue pO2 and microvascular perfusion measurement in the kidney. Our results raise some concerns regarding the accuracy of these OxyLite fluorescence probes for pO2 measurement in the kidney, particularly within the renal cortex.

Propofol attenuates oxidant-induced acute lung injury in an isolated perfused rabbit-lung model.

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Yumoto, Masato; Nishida, Osamu; Nakamura, Fujio; Katsuya, Hirotada

2005-01-01

Reactive oxygen species have been strongly implicated in the pathogenesis of acute lung injury (ALI). Some animal studies suggest that free radical scavengers inhibit the onset of oxidant-induced ALI. Propofol (2,6-diisopropylphenol) is chemically similar to phenol-based free radical scavengers such as the endogenous antioxidant vitamin E. Both in vivo and in vitro studies have suggested that propofol has antioxidant potential. We hypothesized that propofol may attenuate ALI by acting as a free-radical scavenger. We investigated the effects of propofol on oxidant-induced ALI induced by purine and xanthine oxidase (XO), in isolated perfused rabbit lung, in two series of experiments. In series 1, we examined the relationship between the severity of ALI and the presence of hydrogen peroxide (H2O2). In series 2, we evaluated the effects of propofol on attenuating ALI and the dose dependence of these effects. The lungs were perfused for 90 min, and we evaluated the effects on the severity of ALI by monitoring the pulmonary capillary filtration coefficient (Kfc), pulmonary arterial pressure (Ppa), and the pulmonary capillary hydrostatic pressure (Ppc). In series 1, treatment with catalase (an H2O2 scavenger) prior to the addition of purine and XO resulted in complete prevention of ALI, suggesting that H2O2 may be involved closely in the pathogenesis of ALI. In series 2, pretreatment with propofol at concentrations in excess of 0.5 mM significantly inhibited the increases in the Kfc values, and that in excess of 0.75 mM significantly inhibited the increase in the Ppa values. Propofol attenuates oxidant-induced ALI in an isolated perfused rabbit lung model, probably due to its antioxidant action.

The effect of local injection of the human growth hormone on the mandibular condyle growth in rabbit

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Masood Feizbakhsh

2014-01-01

Full Text Available Background: The aim of this study was to evaluate the effect of local injection of human growth hormone (GH in stimulating cartilage and bone formation in a rabbit model of temporomandibular joint (TMJ. Materials and Methods: In an experimental animal study, 16 male Albino New Zealand white rabbits aged 12 weeks were divided into two groups: In the first group (7 rabbits 2 mg/kg/1 ml human GH and in the control group (9 rabbits 1 ml normal saline was administered locally in both mandibular condyles. Injections were employed under sedation and by single experienced person. Injections were made for 6 times with 3 injections a week in the all test and control samples. Rabbits were sacrified at the 20th day from the beginning of study and TMJs were histologically examined. ANOVA (two-sided with Dunnett post hoc test was used to compare data of bone and cartridge thickness while chi-square test was used to analyze hyperplasia and disk deformity data. P < 0.05 was considered as significant. Results: Cartilage layer thickness was greater in the GH-treated (0.413 ± 0.132 than the control group (0.287 ± 0.098 (P value = 0.02. Although bone thickness and condylar cartilage hyperplasia were greater in the GH-treated group, these differences were not statistically significant (P value = 0.189 and 0.083, respectively. There was no statistically significant difference between two groups regarding the disc deformity (P value = 0.46. Conclusion: Local injection of human GH in the TMJ is able to accelerate growth activity of condylar cartilage in rabbit.

Characterizing potential heart agents with an isolated perfused heart system

International Nuclear Information System (INIS)

Pendleton, D.B.; Sands, H.; Gallagher, B.M.; Camin, L.L.

1984-01-01

The authors have used an isolated perfused heart system for characterizing potential myocardial perfusion radiopharamaceuticals. Rabbit or guinea pig (GP) hearts are removed and perfused through the aorta with a blood-free buffer. Heart rate and ventricular pressure are monitored as indices of viability. Tc-99m-MAA is 96-100% retained in these hearts, and Tc-99m human serum albumin shows less than 5% extraction. Tl-201 is 30-40% extracted. It is known that in-vivo, Tc-99m(dmpe)/sub 2/Cl/sub 2//sup +/ is taken up by rabbit heart but not by GP or human heart. Analogous results are obtained with the isolated perfused heart model, where the complex is extracted well by the isolated rabbit heart (24%) but not by the GP heart (<5%). Values are unchanged if human, rabbit or GP blood is mixed and co-injected with the complex. Tc-99m)dmpe)/sub 3//sup +/ is also taken up by rabbit but not by GP hearts in-vivo. However, isolated perfused hearts of both species extract this complex well (45-52%). Heart uptake is diminished to <7% if the complex is pre-equilibrated with human blood. GP blood produces a moderate inhibition (in GP hearts only) and rabbit blood has no effect. This suggests that a human or GP blood factor may have a significant effect on heart uptake of this complex. Tc-99m(CN-t-butyl)/sub 6//sup +/ is taken up well by both rabbit and GP hearts in-vivo, and is extracted 100% by both isolated perfused hearts. Heart retention remains high (73-75%) in the presence of human blood

Effects of ethanol and hyperosmotic perfusates on albumin synthesis and release

International Nuclear Information System (INIS)

Rothschild, M.A.; Oratz, M.; Schreiber, S.S.; Mongelli, J.

1986-01-01

Sucrose and ethanol inhibit albumin synthesis; sucrose via an osmotic mechanism and ethanol during its metabolism. The present study was undertaken to compare the effects of both of these agents on albumin synthesis and secretion, and to see if ethanol inhibition could be related to an osmotic effect. Male, fed rabbits served as liver donors in all studies. There were a total of 35 studies: 13 control; 10 ethanol (39 to 52 mM); 4 cycloheximide (0.5 mM), and 8 sucrose (1%). Plasma volume was measured with 125 I-albumin (human) and extracellular volume measured with either /sup 99m/Tc diethylenetriamine pentaacetic acid or [ 14 C]sucrose. During perfusion, rabbit albumin content in the perfusate was measured immunologically every 15 to 30 min for 225 min. Interstitial albumin efflux was measured by the rate of appearance in the perfusate of 125 I-albumin given to 10 other rabbits 3 days prior to hepatic removal and perfusion. During the initial 75 min of perfusion, 74% of the in vivo equilibrated exchangeable 125 I-albumin appeared in the perfusate, and during this period the rabbit albumin that entered the perfusate was taken to represent efflux from the interstitial volume plus synthesis. Rabbit albumin appearing in the perfusate during the later period of 150 min was taken to represent mainly synthesis and was used to calculate the amount of albumin that would be synthesized in 75 min. The difference between these two values would be hepatic interstitial albumin appearing in the perfusate

Comparative study of rabbit VX2 hepatic implantation tumor and normal liver tissue on magnetic resonance perfusion weighted imaging

International Nuclear Information System (INIS)

Jiao Zimei; Wang Xizhen; Wang Bin; Liu Feng; Li Haiqing; Sun Yequan; Dong Peng

2012-01-01

Objective: To investigate the value of magnetic resonance (MR) perfusion weighted imaging (PWI) in evaluating the blood perfusion of tumor by analyzing the features and indexes of PWI on rabbit VX2 hepatic implantation tumor and normal liver tissue. Methods: Twenty-four New Zealand White rabbits with VX2 carcinoma were established under direct surgical vision embedding tumor tissue. MR examination was performed at 21 days after the tumor implantation. The signal intensity -time curve of hepatic tumor and normal liver tissue were obtained. Mean time to enhance (MTE), negative enhancement integral (NEI), time to minimum (TM), maximum slope of decrease (MSD) and maximum slope of increase (MSI) were measured. Results: MTE, NEI, TM, MSD, and MSI of the normal liver tissue were 208.341±2.226 ms, 78.334±8.152, 24.059±1.927 ms, 38.221±2.443, and 15.389±2.526, respectively. MTE, NEI, TM, MSD, and MSI of the tumor tissue were 175.437±4.182 ms, 123.203±19.455, 17.061±1.834 ms, 125.740±4.842, and 67.832±2.882, respectively. The MTE and TM of tumor were shorter than those of normal hepatic tissue (P<0.05). NEI, MSD, and MSI of tumor were higher than those of normal hepatic tissue (P<0.05). Conclusion: PWI can distinguish the normal liver tissue from the tumor tissue, which is helpful in evaluating blood perfusion of different hepatic tissues. (authors)

Sildenafil improves blood perfusion in steroid-induced avascular necrosis of femoral head in rabbits via a protein kinase G-dependent mechanism.

Science.gov (United States)

Song, Qichun; Ni, Jianlong; Jiang, Hongyuan; Shi, Zhibin

2017-10-01

The aim of the study were to evaluate the effect of sildenafil against avascular necrosis of femoral head (ANFH) in a rabbit model, and to study the role of protein kinase G (PKG) pathway and vascular endothelial growth factor (VEGF) in ANFH. Three weeks after inducing ANFH with methylprednisolone injection, 45 female adult New Zealand white rabbits were divided into three groups and treated as follows: group SI received daily intraperitoneal sildenafil with a dose of 10 mg/kg per day; group SD received daily sildenafil identically to group SI plus auricular vein injection DT3 (a specific PKG inhibitor); group NS received only normal saline. The blood perfusion function in the femoral head was measured by perfusion MRI and ink artery infusion. Bilateral femora heads were examined histopathologically for the presence of osteonecrosis; VEGF of tissue was examined by Western blot analysis; cGMP level and PKG activity were also measured. The incidence of ANFH in SI group was significantly lower than that observed in NS and SD groups (p < 0.05). VEGF in SI group was increased compared to NS group. cGMP level and PKG activity were also significantly different between NS and SI group (p < 0.05). However, these effects of sildenafil in SD group were all markedly inhibited by the administration of DT3 compared to SI group. Sildenafil appear to increase the perfusion of femoral head by up-regulating VEGF through PKG pathway. The increased perfusion of femoral head could prevent ANFH. Copyright © 2017 Turkish Association of Orthopaedics and Traumatology. Production and hosting by Elsevier B.V. All rights reserved.

Evaluation of femoral perfusion in a rabbit model of steroid-induced osteonecrosis by dynamic contrast-enhanced MRI with a high magnetic field MRI system.

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Hayashi, Shigeki; Fujioka, Mikihiro; Ikoma, Kazuya; Saito, Masazumi; Ueshima, Keiichiro; Ishida, Masashi; Kuribayashi, Masaaki; Ikegami, Akira; Mazda, Osam; Kubo, Toshikazu

2015-04-01

To evaluate perfusion during the early phase after steroid administration in vivo using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) with a high magnetic field MRI system. The main pathogenesis of steroid-induced osteonecrosis is considered to be ischemia. A single dose of methylprednisolone (MPSL) was injected into nine rabbits. DCE-MRI was performed for these rabbits before MPSL administration and 1, 5, 10, and 14 days after administration. Time-signal intensity curves were created for each femur based on the signal intensity to evaluate perfusion. Enhancement ratio (ER), initial slope (IS), and area under the curve (AUC) were calculated and the value before MPSL administration and the minimal value after administration were compared statistically. ER, IS, and AUC values after MPSL administration significantly decreased (P < 0.05, P < 0.01, and P < 0.01, respectively). All of them decreased by the 5th day in 56% of the femora and by the 14th day in 83%, and some femora even showed a decrease from the 1st day. In this study, decreased perfusion in the femora after steroid administration was proven. Additionally, we could show that it occurred from the early days after steroid administration. © 2014 Wiley Periodicals, Inc.

Absolute concentration determination of phosphorus metabolites in the Langendorff-perfused rabbit heart by phosphorus-31 nuclear magnetic resonance

International Nuclear Information System (INIS)

Gard, J.K.

1984-01-01

The concentrations of mobile high energy phosphorus metabolites and intracellular pH of Langendorff-perfused rabbit heart have been determined under control and reduced flow conditions. Absolute concentration determination was accomplished by Lorentzian lineshape analysis after development of hexachlorocyclotriphosphazene as an external intensity standard. Hearts were demonstrated to be biochemically and physiologically competent during control perfusion periods and compromised during reduced flow conditions by independent hemodynamic and metabolic measurements coincident with the NMR experiment. Reduction in perfusate flow from 20 mL/min to 5.0 mL/min (25% flow) or 2.5 mL/min (12.5% flow) demonstrated a fall in phosphocreatine and adenosine triphosphate concentrations, a rise in cytosolic inorganic phosphate concentrations, and drops in pH. Subsequent recovery upon reflow was observed. The derived values for the free concentration of ADP were very close to the reported values of the Michaelis constant for respiratory stimulation, implicating a regulatory role for this molecule in cellular respiration. Strong evidence that the creating kinase reaction was in equilibrium in the 25% flow study was seen. The NMR observable correlated closely with myocardial performance and biochemical indices of metabolic function, and supported the use of phosphocreatine as an indicator of current metabolic integrity

Does the titanium plate fixation of symphyseal fracture affect mandibular growth?

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Bayram, Burak; Yilmaz, Alev Cetinsahin; Ersoz, Esra; Uckan, Sina

2012-11-01

The effect of metallic fixation on growth is a major concern in children and is not yet clear. The aim of this study was to evaluate the effect of metallic fixation of mandibular symphyseal fracture on mandibular growth.Eighteen 90-day-old growing white New Zealand rabbits weighing 1.6 to 2.5 kg were included in this study and divided into 2 groups of 9 subjects. In the experimental group, animals underwent mandibular osteotomy, simulating a symphyseal fracture on the midline of mandibular symphysis. The bone segments were fixed with microplates and microscrews (1.6 mm).In the control group, the same surgical incision without performing symphyseal osteotomy was conducted, and 2 screws were inserted on each side of the symphyseal midline.Digital cephalometric and submentovertex radiographs were taken before the operation and at postoperative 6 months for each animal in 2 groups, and cephalometric measurements were performed. The distance between the centers of the head of 2 screws measured at the end of surgery in the control group was compared with measurements at 6 months after surgery. Obtained data were statistically analyzed.There is no statistically significant difference between the 2 groups for growth amount of both sides of the mandible. Difference of ANS-Id (the most anterior points of nasal bone, the most anterior point on the alveolar bone between the lower incisors) and Cd-Id (the uppermost and most distal point of the mandibular condyle, the most anterior point on the alveolar bone between the lower incisors) values of the 2 groups is not statistically significant (P > 0.05).The distance between the 2 screws at the first application significantly increased at the postoperative sixth month (P mandibular symphyseal fracture does not affect the vertical and sagittal mandibular growth in growing rabbits.

Effect of Garlic on Perfusion Scintigraphy of Rabbit's Lungs ...

African Journals Online (AJOL)

Animals. A total number of 12 mixed bred rabbits weighing. 3.5 ± 0.5 kg were selected. Then, the necessary blood and parasite analysis as well as clinical ..... 8. Flecknell PA, Ed. BSAVA manual of rabbit medicine and surgery. London: British Small Animal Veterinary. Association; 2000; pp 30-31, 106. 9. Ji Y, Gao H, Zhang ...

Whole-liver MR perfusion imaging in rabbit liver VX2 tumors: early findings of coagulative necrosis after percutaneous ethanol injection therapy

International Nuclear Information System (INIS)

Zhang Wanshi; Wang Dong; Meng Limin; Shi Huiping; Song Yunlong; Wu Bing

2007-01-01

Objective: To investigate the value of whole-liver MR perfusion imaging (MRPI) for early detection of coagulative necrosis after percutaneous ethanol injection (PEI) in rabbit liver VX 2 tumors. Methods: VX 2 tumor cell suspension was inoculated into rabbit liver and liver VX 2 tumors [diameter of (2.6 ± 0.6) cm] were induced in 10 male rabbits. MR T 1 WI and T 2 WI were performed to monitor the development of the liver tumor on the 2 nd and 3 rd week after inoculation. Whole-liver MRPI was performed in the 10 rabbits with liver VX 2 tumors before and 6 days after PEI therapy (1.0 ml ethanol was injected into the most enhanced tumor region under CT guiding). Signal intensity (SI) values of untreated tumor parts and treated areas 6 days after PEI were recorded respectively. The steepest slope (SS) and bolus arrival time (T0) of SI-time curves were measured. The t-Student test was used in statistical analysis of the data. Results: There was significant difference in MRPI data between untreated tumor parts [T0: (16.0 ± 1.2) s and SS: 38.9 ± 2.2] and treated areas [T0: (50.8 ± 5.9) s and SS: 6.0 ± 1.2] 6 days after PEI(t was 15.8 and -39.6 respectively, P 1 WI and T 2 WI could not show any differences between untreated tumor parts and treated areas. Conclusion: Whole-liver MRPI could detect coagulative necrosis of rabbit liver VX 2 tumors after PEI early. Disappearance of early enhancement can be a potential marker for efficacy of PEI. (authors)

Removal of atrial natriuretic factor by perfused rabbit lungs in situ

International Nuclear Information System (INIS)

Turrin, M.; Maack, T.; Gillis, C.N.

1986-01-01

Because atrial natriuretic factor (ANF) can be released from the right atrium into pulmonary blood, the authors studied the possibility of uptake of the peptide by rabbit lung, perfused in situ, at 20 ml/min with Krebs-albumin medium. Single pass removal (multiple indicator dilution with 14 C-dextran as reference) of trace amounts (40 pmoles) of 125 I-ANF was 66 +/- 4% (n=12). This was reduced to 8 +/- 4% by co-injection of 10 μM ANF but was unchanged by co-injection of CPAP (340 nM), an inhibitor of angiotensin-converting enzyme (ACE). When 125 I-ANF was re-circulated through lung, uptake reached maximum at 14 min (64 +/- 5%; n=7). Efflux of 125 I-ANF from preloaded lungs was monoexponential with t/sub 1/2/ = 17.7 min. Recovery of 125 I-ANF uptake after block by unlabelled ANF was studied. For this purpose, lungs were loaded with 0.1 μM unlabelled ANF by recirculating for 20 minutes, after which medium was changed to Krebs-albumin and removal of bolus injections of 125 I-ANF was measured every 5 min. Removal of 125 I-ANF, initially 0%, returned to control levels after 20 min. Thus, 125 I-ANF is removed from the pulmonary circulation by a saturable and reversible process which probably does not involve binding to the ACE present on endothelial cells

Effect of adenosine1-receptor blockade on renin release from rabbit isolated perfused juxtaglomerular apparatus

DEFF Research Database (Denmark)

Weihprecht, H; Lorenz, J N; Schnermann, J

1990-01-01

Adenosine has been proposed to act within the juxtaglomerular apparatus (JGA) as a mediator of the inhibition of renin secretion produced by a high NaCl concentration at the macula densa. To test this hypothesis, we studied the effects of the adenosine1 (A1)-receptor blocker 8-cyclopentyl-1......,3-dipropylxanthine (CPX) on renin release from single isolated rabbit JGAs with macula densa perfused. The A1-receptor agonist, N6-cyclohexyladenosine (CHA), applied in the bathing solution at 10(-7) M, was found to inhibit renin secretion, an effect that was completely blocked by adding CPX (10(-5) M) to the bath....... Applied to the lumen, 10(-5) M CPX produced a modest stimulation of renin secretion rates suppressed by a high NaCl concentration at the macula densa (P less than 0.05). The effect of changing luminal NaCl concentration on renin secretion rate was examined in the presence of CPX (10(-7) and 10(-5) M...

A comparison of perfusion computed tomography and contrast enhanced computed tomography on radiation target volume delineation using rabbit VX2 brain tumor model

International Nuclear Information System (INIS)

Sun Changjin; Luo Yunxiu; Yu Jinming; Lu Haibo; Li Chao; Zhang Dekang; Huang Jianming; Wang Jie; Lang Jinyi

2010-01-01

Objective: To compare the accuracy of blood volume perfusion imaging (perfusion CT)with contrast enhanced 64-slice spiral computed tomography (CECT) in the evaluation of gross tumor volume (GTV) and clinical target volume (CTV) using rabbits with VX2 brain tumor. Methods: Perfusion CT and CECT were performed in 20 rabbits with VX2 brain tumor. The GTV and CTV calculated with the maximal and minimal diameter of each tumor in the blood volume (BV) maps and CECT were measured and compared to those in pathological specimens. Results: The mean value of the maximal and minimal diameter of GTV was (8.19 ± 2.29) mm and (4.83 ± 1.31) mm in pathological specimens, (11.98 ±3.29) mm and (7.03±1.82) mm in BV maps, while (6.36±3.85) mm and (3.17±1.93) mm in CECT images, which were significantly different (pathological specimen vs. BV map, t = 7.17, P =0.000;pathological specimen vs. CECT, t = 8.37, P = 0.000, respectively). The mean value of the maximal and minimal diameter of CTV in pathologic specimens was (12.87 ± 3.74) mm and (7.71 ± 2.15) mm, which was significantly different from that of GTV and CTV in CECT (t = - 3. 18, P = 0. 005 and t = - 4.24, P =0.000; t= -11.59,P=0.000 and t= -9.39, P=0.000), while similar with that of GTV in BV maps (t = - 1.95,P = 0. 067; t = - 2. 06, P = 0. 054). For CECT, the margin from GTV to CTV was 81.83% ±40.33% for the maximal diameter and 276.73% ± 131.46% for the minimal. While for BV maps, the margin was 7.93% ± 17. 84% and 12.52% ± 27. 83%, which was significant different from that for CECT images (t=7.36, P=0. 000 and t= -8.78, P=0.000). Conclusions: Compared with CECT, the BV map from 64-slice spiral CT perfusion imaging might have higher accuracy in target volume delineation for brain tumor. (authors)

Glycosaminoglycan synthesis in the mandibular condyle during growth adaptation.

Science.gov (United States)

Kantomaa, T; Pirttiniemi, P; Tuominen, M; Poikela, A

1994-01-01

Condylar growth was studied after an operation simulating functional orthodontic appliances. Twenty-five rabbits underwent a surgical operation for the induction of premature synostosis to displace the glenoid fossa posteriorly during growth. Twenty-five control rabbits underwent sham operations. At the age of 15 days, 10 experimental and 10 control animals and, at the age of 20 days, 5 experimental and 5 control animals were killed. Their mandibular condyles were organ-cultured for 3 h in the presence of radiolabelled sulphur. The condyles were used for autoradiographic purposes. Digital image analysis of autoradiograms of histological sections showed synthesis of glycosaminoglycans to have increased from the anterior to the posterior direction. This increase was more marked in experimental animals than in the condyles of control animals. Ten experimental and 10 control animals were killed at the age of 15 days, and mandibular condyles were organ-cultured for 1, 4 and 7 days. Differentiation of proliferating prechondroblasts into hypertrophied chondrocytes continued under organ culture conditions. A marked decrease in the proliferating cell layer was noticed, especially in control condyles. Hypertrophy was faster and came closer to the surface of the condyle in the anterior region of the condyle. This was most marked in the condyles of experimental animals. The results indicate that a procedure carried out on the glenoid fossa with the same effect as functional appliances increases the synthesis of extracellular matrix in the posterosuperior region of the mandibular condyle.

Validation of transport measurements in skeletal muscle with N-13 amino acids using a rabbit isolated hindlimb model

International Nuclear Information System (INIS)

Conlon, K.C.; Bading, J.R.; DiResta, G.R.; Corbally, M.T.; Gelbard, A.S.; Brennan, M.F.

1989-01-01

The authors are studying the transport of C-11 and N-13 labeled amino acids in tumor-bearing rabbits to determine the role of amino acid transport in the pathogenesis of muscle wasting in cancer. To validate a new, in vivo, method for measuring transport in skeletal muscle with these compounds, an isolated hindlimb model was developed in rabbits. The limb was perfused with a non-recirculating, normothermic, constant pressure system and a cell-free perfusate. Hemodynamic and metabolic parameters were measured during the first 75 min. of perfusion and found to remain normal and stable. Flow varied directly with perfusion pressure over the normal range of resting flows in the intact rabbit hindlimb. Time-activity curves (TAC's) were recorded from the medial thigh following bolus co-injection of L-[amide N-13] glutamine or N-13 L-glutamate with Tc-99m human serum albumin (HSA) into the femoral artery. Regional plasma flow was determined from the Tc-99m data

Removal of atrial natriuretic factor by perfused rabbit lungs in situ

Energy Technology Data Exchange (ETDEWEB)

Turrin, M.; Maack, T.; Gillis, C.N.

1986-03-05

Because atrial natriuretic factor (ANF) can be released from the right atrium into pulmonary blood, the authors studied the possibility of uptake of the peptide by rabbit lung, perfused in situ, at 20 ml/min with Krebs-albumin medium. Single pass removal (multiple indicator dilution with /sup 14/C-dextran as reference) of trace amounts (40 pmoles) of /sup 125/I-ANF was 66 +/- 4% (n=12). This was reduced to 8 +/- 4% by co-injection of 10 ..mu..M ANF but was unchanged by co-injection of CPAP (340 nM), an inhibitor of angiotensin-converting enzyme (ACE). When /sup 125/I-ANF was re-circulated through lung, uptake reached maximum at 14 min (64 +/- 5%; n=7). Efflux of /sup 125/I-ANF from preloaded lungs was monoexponential with t/sub 1/2/ = 17.7 min. Recovery of /sup 125/I-ANF uptake after block by unlabelled ANF was studied. For this purpose, lungs were loaded with 0.1 ..mu..M unlabelled ANF by recirculating for 20 minutes, after which medium was changed to Krebs-albumin and removal of bolus injections of /sup 125/I-ANF was measured every 5 min. Removal of /sup 125/I-ANF, initially 0%, returned to control levels after 20 min. Thus, /sup 125/I-ANF is removed from the pulmonary circulation by a saturable and reversible process which probably does not involve binding to the ACE present on endothelial cells.

Oxidative Damage and Mitochondrial Injuries Are Induced by Various Irrigation Pressures in Rabbit Models of Mild and Severe Hydronephrosis

Science.gov (United States)

Cao, Zhixiu; Yu, Weimin; Li, Wei; Cheng, Fan; Rao, Ting; Yao, Xiaobing; Zhang, Xiaobin; Larré, Stéphane

2015-01-01

Objective We aimed to study whether tolerance to irrigation pressure could be modified by evaluating the oxidative damage of obstructed kidneys based on rabbit models experiencing different degrees of hydronephrosis. Methods A total of 66 rabbits were randomly divided into two experimental groups and a control group. In the experimental groups, the rabbits underwent a surgical procedure inducing mild (group M, n=24) or severe (group S, n=24) hydronephrosis. In each experimental group, the rabbits were then randomly divided into 4 subgroups (M0-M3 and S0-S3) consisting of 6 rabbits each. Group 0 received no perfusion. Groups 1 through 3 were perfused with 20, 60 and 100 mmHg fluid, respectively. For the control group, after a sham operation was performed, the rabbits were divided into 4 subgroups and were perfused with fluid at 0, 20, 60 or 100 mmHg of pressure. Kidney injuries was evaluated by neutrophil gelatinase associated lipocalin (NGAL). Oxidative damage was assessed by analyzing superoxide dismutase (Mn-SOD) activity, malondialdehyde (MDA) levels, glutathione reductase (GR), catalase (CAT) and peroxide (H2O2) levels, mitochondrial injuries was assessed by mitochondrial membrane potential (MMP), the mitochondrial ultrastructure and tubular cell apoptosis. Results In the experimental groups, all results were similar for groups 0 and 1. In group 2, abnormalities were observed in the S group only, and the kidneys of rabbits in group 3 suffered oxidative damage and mitochondrial injuries with increased NGAL, decreased Mn-SOD, GR and CAT,increased MDA and H2O2, lower levels of MMP, mitochondrial vacuolization and an increased apoptotic index. Conclusion In rabbits, severely obstructed kidneys were more susceptible to oxidative damage and mitochondrial injury than mildly obstructed kidneys when subjected to higher degrees of kidney perfusion pressure. PMID:26090815

Oxidative Damage and Mitochondrial Injuries Are Induced by Various Irrigation Pressures in Rabbit Models of Mild and Severe Hydronephrosis.

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Zhixiu Cao

Full Text Available We aimed to study whether tolerance to irrigation pressure could be modified by evaluating the oxidative damage of obstructed kidneys based on rabbit models experiencing different degrees of hydronephrosis.A total of 66 rabbits were randomly divided into two experimental groups and a control group. In the experimental groups, the rabbits underwent a surgical procedure inducing mild (group M, n=24 or severe (group S, n=24 hydronephrosis. In each experimental group, the rabbits were then randomly divided into 4 subgroups (M0-M3 and S0-S3 consisting of 6 rabbits each. Group 0 received no perfusion. Groups 1 through 3 were perfused with 20, 60 and 100 mmHg fluid, respectively. For the control group, after a sham operation was performed, the rabbits were divided into 4 subgroups and were perfused with fluid at 0, 20, 60 or 100 mmHg of pressure. Kidney injuries was evaluated by neutrophil gelatinase associated lipocalin (NGAL. Oxidative damage was assessed by analyzing superoxide dismutase (Mn-SOD activity, malondialdehyde (MDA levels, glutathione reductase (GR, catalase (CAT and peroxide (H2O2 levels, mitochondrial injuries was assessed by mitochondrial membrane potential (MMP, the mitochondrial ultrastructure and tubular cell apoptosis.In the experimental groups, all results were similar for groups 0 and 1. In group 2, abnormalities were observed in the S group only, and the kidneys of rabbits in group 3 suffered oxidative damage and mitochondrial injuries with increased NGAL, decreased Mn-SOD, GR and CAT,increased MDA and H2O2, lower levels of MMP, mitochondrial vacuolization and an increased apoptotic index.In rabbits, severely obstructed kidneys were more susceptible to oxidative damage and mitochondrial injury than mildly obstructed kidneys when subjected to higher degrees of kidney perfusion pressure.

Fabrication and perfusion culture of anatomically shaped artificial bone using stereolithography

International Nuclear Information System (INIS)

Du, Dajiang; Asaoka, Teruo; Ushida, Takashi; Furukawa, Katsuko S

2014-01-01

Because patient bone defects are usually varied and complicated in geometry, it would be preferred to fabricate custom-made artificial bone grafts that are anatomically specific to individual patient defects. Using a rabbit femoral segment as a bone reconstruction model, we successfully produced customized ceramic scaffolds by stereolithography, which not only had an anatomically correct external shape according to computed tomography data but also contained an interconnecting internal network of channels designed for perfusion culture. Rabbit bone marrow stromal cells were isolated and cultured with these scaffolds using a novel oscillatory perfusion system that was stereolithographically fabricated to fit well to the unique scaffold shapes. After five days of three-dimensional culture with oscillatory perfusion, the cells attached and proliferated homogenously in the scaffolds. However, control cells inside the scaffolds cultured under static conditions were dead after prolonged in vitro culture. Cellular DNA content and alkaline phosphatase activities were significantly higher in the perfusion group versus the static group. Therefore, anatomically correct artificial bone can be successfully constructed using stereolithography and oscillatory culture technology, and could be useful for bone engraftment and defect repair. (paper)

Dynamic MR imaging of mandibular osteoradionecrosis

International Nuclear Information System (INIS)

Store, G.; Smith, H.J.; Larheim, T.A.

2000-01-01

Osteoradionecrotic bone has been characterised as hypovascular and metabolically inactive tissue with impaired perfusion. The present study was conducted to determine if dynamic contrast-enhanced MR imaging could provide additional information about the vascularity of radionecrotic mandibular bone. Dynamic contrast-enhanced MR imaging was performed on 10 patients with mandibular osteoradionecrosis (ORN), and on 6 patients, irradiated for oropharyngeal tumours, without symptoms or signs of ORN. Nine patients in the ORN group received a series of 20 hyperbaric oxygen (HBO) treatments, after which the dynamic MR investigation was repeated. Radiation per se did not lead to increased contrast enhancement, whereas all patients with ORN showed marked contrast enhancement of the osteoradionecrotic bone marrow. After HBO treatment, pathological contrast enhancement of the abnormal bone marrow could still be seen, but the rate of enhancement was less than before in 7 of 9 patients. Two patients had an increase in the enhancement rate. The findings suggest the existence of an increased and patent microvasculature

Pharmacological activation of Kv11.1 in transgenic long QT-1 rabbits

DEFF Research Database (Denmark)

Bentzen, Bo Hjorth; Bahrke, Sophia; Wu, Kezhong

2011-01-01

Transgenic rabbits expressing pore mutants of K(V)7.1 display a long QT syndrome 1 (LQT1) phenotype. Recently, NS1643 has been described to increase I(Kr).We hypothesized that NS1643 would shorten the action potential duration (APD(90)) in LQT1 rabbits. Transgenic LQT1 rabbits were compared...... with littermate control (LMC) rabbits. In vivo electrocardiogram studies in sedated animals were performed at baseline and during 45 minutes of intravenous infusion of NS1643 or vehicle in a crossover design. Ex vivo monophasic action potentials were recorded from Langendorff-perfused hearts at baseline...

Adenosine-induced coronary flow reserve in Watanabe heritable hyperlipidemic rabbits

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Shimada, Kazuhiro; Yoshida, Katsuya [Chiba Univ. (Japan). School of Medicine; Tadokoro, Hiroyuki [and others

2000-12-01

The Watanabe heritable hyperlipidemic (WHHL) rabbit develops coronary atherosclerosis and hypercholesterolemia because of a genetic deficiency of low-density lipoprotein receptors and is therefore a good animal model for studying the relationships of coronary atherosclerosis, hypercholesterolemia and coronary flow reserve. The aim of the present study was to assess myocardial perfusion at baseline and during adenosine infusion (0.2 mg{center_dot}kg{sup -1}{center_dot}min{sup -1}) in 8 WHHL rabbits (13.8{+-}0.5 months) with {sup 13}N-ammonia, small-animal positron emission tomography (PET) and colored microspheres. Results were compared with those from 6 age-matched Japanese white rabbits. Plaque distribution was also examined in the extramural coronary arteries. All 8 WHHL rabbits had coronary plaques, with 6 showing multiple plaques. Mean global myocardial blood flow (ml{center_dot}min{sup -1}{center_dot}g{sup -1}) did not differ significantly between control and WHHL groups both at baseline (3.67{+-}0.72 vs 4.26{+-}1.12 ml{center_dot}min{sup -1}{center_dot}g{sup -1}, p=NS) and with adenosine (7.92{+-}2.00 vs 9.27{+-}2.91 ml{center_dot}min{sup -1}{center_dot}g{sup -1}, p=NS), nor did coronary flow reserve (2.16{+-}0.37 vs 2.18{+-}0.41, p=NS). None showed evidence of regional perfusion abnormalities by visual and semiquantitative analyses of PET images. It was concluded that WHHL rabbits preserve adenosine-induced coronary flow reserve despite coronary atherosclerosis and hypercholesterolemia, suggesting that a compensatory mechanism develops in this animal model. (author)

Adenosine-induced coronary flow reserve in Watanabe heritable hyperlipidemic rabbits

International Nuclear Information System (INIS)

Shimada, Kazuhiro; Yoshida, Katsuya; Tadokoro, Hiroyuki

2000-01-01

The Watanabe heritable hyperlipidemic (WHHL) rabbit develops coronary atherosclerosis and hypercholesterolemia because of a genetic deficiency of low-density lipoprotein receptors and is therefore a good animal model for studying the relationships of coronary atherosclerosis, hypercholesterolemia and coronary flow reserve. The aim of the present study was to assess myocardial perfusion at baseline and during adenosine infusion (0.2 mg·kg -1 ·min -1 ) in 8 WHHL rabbits (13.8±0.5 months) with 13 N-ammonia, small-animal positron emission tomography (PET) and colored microspheres. Results were compared with those from 6 age-matched Japanese white rabbits. Plaque distribution was also examined in the extramural coronary arteries. All 8 WHHL rabbits had coronary plaques, with 6 showing multiple plaques. Mean global myocardial blood flow (ml·min -1 ·g -1 ) did not differ significantly between control and WHHL groups both at baseline (3.67±0.72 vs 4.26±1.12 ml·min -1 ·g -1 , p=NS) and with adenosine (7.92±2.00 vs 9.27±2.91 ml·min -1 ·g -1 , p=NS), nor did coronary flow reserve (2.16±0.37 vs 2.18±0.41, p=NS). None showed evidence of regional perfusion abnormalities by visual and semiquantitative analyses of PET images. It was concluded that WHHL rabbits preserve adenosine-induced coronary flow reserve despite coronary atherosclerosis and hypercholesterolemia, suggesting that a compensatory mechanism develops in this animal model. (author)

Intravoxel Incoherent Motion Diffusion Weighted MR Imaging for Monitoring the Instantly Therapeutic Efficacy of Radiofrequency Ablation in Rabbit VX2 Tumors without Evident Links between Conventional Perfusion Weighted Images.

Directory of Open Access Journals (Sweden)

Ziyi Guo

Full Text Available To investigate the intravoxel incoherent motion diffusion weighted imaging (IVIM-DWI as a potential valuable marker to monitor the therapy responses of VX2 to radiofrequency ablation (RF Ablation.The institutional animal care and use committee approved this study. In 10 VX2 tumor-bearing rabbits, IVIM-DWI examinations were performed with a 3.0T imaging unit by using 16 b values from 0 to 800 sec/mm2. The true diffusion coefficient (D, pseudodiffusion coefficient (D* and perfusion fraction (f of tumors were compared between before and instantly after RF Ablation treatment. The differences of D, D* and f and conventional perfusion parameters (from perfusion CT and dynamic enhanced magnetic resonance imaging, DCE-MRI in the coagulation necrosis area, residual unablated area, untreated area, and normal control had been calculated by compared t-test. The correlation between f or D* with perfusion weighted CT including blood flow, BF (milliliter per 100 mL/min, blood volume, BV (milliliter per 100 mL/min, and capillary permeability-surface area, PMB (as a fraction or from DCE-MRI: transfer constant (Ktrans, extra-vascular extra-cellular volume fraction (Ve and reflux constant (Kep values had been analyzed by region-of-interest (ROI methods to calculate Pearson's correlation coefficients.In the ablated necrosis areas, f and D* significantly decreased and D significantly increased, compared with residual unblazed areas or untreated control groups and normal control groups (P < 0.001. The IVIM-DWI derived f parameters showed significant increases in the residual unablated tumor area. There was no significant correlations between f or D* and conventional perfusion parameters.The IVIM-DW derived f, D and D* parameters have the potential to indicate therapy response immediately after RF Ablation treatment, while no significant correlations with classical tumor perfusion metrics were derived from DCE-MRI and perfusion-CT measurements.

Pulmonary O2 transfer during pulsatile and non-pulsatile perfusion.

Science.gov (United States)

Hauge, A; Nicolaysen, G

1980-07-01

The importance of the perfusion pattern for the oxygen transfer has been examined in isolated rabbit lungs perfused with plasma at constant volume inflow. The lungs were ventilated with constant tidal volume and constant end-expiratory pressure. Following a standardized rise in FIO2 the rate of rise in pulmonary venous PO2 (delta PO2/delta t) was measured during alternately pulsatile and non-pulsatile perfusion in normal lungs and in lungs made edematous by elevation of left atrial pressure. In normal lungs there was no difference in delta PO2/delta t when the two modes of perfusion were compared. In edematous lungs delta PO/delta t was statistically higher during pulsatile perfusion, indicating a beneficial effect of flow- and pressure pulsations, e.g. a better distribution of V/Q ratios throughout the lungs. In a separate series of expts. the advancement of a high O2 front through the airways was measured, and the two perfusion patterns compared. Since no difference was found, we suggest that the phenomenon of "cardiogenic gas mixing" in the airways in vivo is a result of a direct action of the heart on the lungs rather than arterial pulsations.

Thermoablation of Malignant Kidney Tumors Using Magnetic Nanoparticles: An In Vivo Feasibility Study in a Rabbit Model

International Nuclear Information System (INIS)

Bruners, Philipp; Braunschweig, Till; Hodenius, Michael; Pietsch, Hubertus; Penzkofer, Tobias; Baumann, Martin; Guenther, Rolf W.; Schmitz-Rode, Thomas; Mahnken, Andreas H.

2010-01-01

The objective of this study was to assess the technical feasibility of CT-guided magnetic thermoablation for the treatment of malignant kidney tumors in a VX2 tumor rabbit model. VX2 tumors were implanted into the kidneys of five rabbits and allowed to grow for 2 weeks. After preinterventional CT perfusion imaging, CT-guided injection of superparamagnetic iron oxide particles (300 μl) was performed, followed by exposure of the animals to an alternating electromagnetic field for 15 min (∼0.32 kA/m). Then animals underwent CT perfusion imaging again. Afterward, animals were sacrificed and kidneys were dissected for macroscopic and histological evaluation. Changes in perfusion before and after exposure to the alternating magnetic field were analyzed. In one animal no tumor growth could be detected so the animal was used for optimization of the ablation procedure including injection technique and peri-interventional cross-sectional imaging (CT, MRI). After image-guided intratumoral injection of ferrofluids, the depiction of nanoparticle distribution by CT correlated well with macroscopic evaluation of the dissected kidneys. MRI was limited due to severe susceptibility artefacts. Postinterventional CT perfusion imaging revealed a perfusion deficiency around the ferrofluid deposits. Histological workup showed different zones of thermal damage adjacent to the ferrofluid deposits. In conclusion, CT-guided magnetic thermoablation of malignant kidney tumors is technically feasible in an animal model and results in a perfusion deficiency indicating tumor necrosis as depicted by CT perfusion imaging and shown in histological evaluation.

Enhancement of osteogenesis and biodegradation control by brushite coating on Mg-Nd-Zn-Zr alloy for mandibular bone repair.

Science.gov (United States)

Guan, Xingmin; Xiong, Meiping; Zeng, Feiyue; Xu, Bin; Yang, Lingdi; Guo, Han; Niu, Jialin; Zhang, Jian; Chen, Chenxin; Pei, Jia; Huang, Hua; Yuan, Guangyin

2014-12-10

To diminish incongruity between bone regeneration and biodegradation of implant magnesium alloy applied for mandibular bone repair, a brushite coating was deposited on a matrix of a Mg-Nd-Zn-Zr (hereafter, denoted as JDBM) alloy to control the degradation rate of the implant and enhance osteogenesis of the mandible bone. Both in vitro and in vivo evaluations were carried out in the present work. Viability and adhesion assays of rabbit bone marrow mesenchyal stem cells (rBM-MSCs) were applied to determine the biocompatibility of a brushite-coated JDBM alloy. Osteogenic gene expression was characterized by quantitative real-time polymerase chain reaction (RT-PCR). Brushite-coated JDBM screws were implanted into mandible bones of rabbits for 1, 4, and 7 months, respectively, using 316L stainless steel screws as a control group. In vivo biodegradation rate was determined by synchrotron radiation X-ray microtomography, and osteogenesis was observed and evaluated using Van Gieson's picric acid-fuchsin. Both the naked JDBM and brushite-coated JDBM samples revealed adequate biosafety and biocompatibility as bone repair substitutes. In vitro results showed that brushite-coated JDBM considerably induced osteogenic differentiation of rBM-MSCs. And in vivo experiments indicated that brushite-coated JDBM screws presented advantages in osteoconductivity and osteogenesis of mandible bone of rabbits. Degradation rate was suppressed at a lower level at the initial stage of implantation when new bone tissue formed. Brushite, which can enhance oeteogenesis and partly control the degradation rate of an implant, is an appropriate coating for JDBM alloys used for mandibular repair. The Mg-Nd-Zn-Zr alloy with brushite coating possesses great potential for clinical applications for mandibular repair.

Activation of rho is involved in the mechanism of hydrogen-peroxide-induced lung edema in isolated perfused rabbit lung.

Science.gov (United States)

Chiba, Y; Ishii, Y; Kitamura, S; Sugiyama, Y

2001-09-01

Acute lung injury is attributed primarily to increased vascular permeability caused by reactive oxygen species derived from neutrophils, such as hydrogen peroxide (H2O2). Increased permeability is accompanied by the contraction and cytoskeleton reorganization of endothelial cells, resulting in intercellular gap formation. The Rho family of Ras-like GTPases is implicated in the regulation of the cytoskeleton and cell contraction. We examined the role of Rho in H2O2-induced pulmonary edema with the use of isolated perfused rabbit lungs. To our knowledge, this is the first study to examine the role of Rho in increased vascular permeability induced by H2O2 in perfused lungs. Vascular permeability was evaluated on the basis of the capillary filtration coefficient (Kfc, ml/min/cm H2O/100 g). We found that H2O2 (300 microM) increased lung weight, Kfc, and pulmonary capillary pressure. These effects of H2O2 were abolished by treatment with Y-27632 (50 microM), an inhibitor of the Rho effector p160 ROCK. In contrast, the muscular relaxant papaverine inhibited the H2O2-induced rise in pulmonary capillary pressure, but did not suppress the increases in lung weight and Kfc. These findings indicate that H2O2 causes pulmonary edema by elevating hydrostatic pressure and increasing vascular permeability. Y-27632 inhibited the formation of pulmonary edema by blocking both of these H2O2-induced effects. Our results suggest that Rho-related pathways have a part in the mechanism of H2O2-induced pulmonary edema. Copyright 2001 Academic Press.

Bile acid flux through portal but not peripheral veins inhibits CYP7A1 expression without involvement of ileal FGF19 in rabbits.

Science.gov (United States)

Shang, Quan; Guo, Grace L; Honda, Akira; Shi, Daniel; Saumoy, Monica; Salen, Gerald; Xu, Guorong

2014-08-15

It was proposed that CYP7A1 expression is suppressed through the gut-hepatic signaling pathway fibroblast growth factor (FGF) 15/19-fibroblast growth factor receptor 4, which is initiated by activation of farnesoid X receptor in the intestine rather than in the liver. The present study tested whether portal bile acid flux alone without ileal FGF19 could downregulate CYP7A1 expression in rabbits. A rabbit model was developed by infusing glycodeoxycholic acid (GDCA) through the splenic vein to bypass ileal FGF19. Study was conducted in four groups of rabbits: control; bile fistula + bovine serum albumin solution perfusion (BF); BF + GDCA (by portal perfusion); and BF + GDCA-f (by femoral perfusion). Compared with only BF, BF + GDCA (6 h portal perfusion) suppressed CYP7A1 mRNA, whereas BF + GDCA-f (via femoral vein) with the same perfusion rate of GDCA did not show inhibitory effects. Meanwhile, there was a decrease in ileal FGF19 expression and portal FGF19 protein levels, but an equivalent increase in biliary bile acid outputs in both GDCA perfusion groups. This study demonstrated that portal bile acid flux alone downregulated CYP7A1 expression with diminished FGF19 expression and protein levels, whereas the same bile acid flux reaching the liver through the hepatic artery via femoral vein had no inhibitory effect on CYP7A1. We propose that bile acid flux through the portal venous system may be a kind of "intestinal factor" that suppresses CYP7A1 expression. Copyright © 2014 the American Physiological Society.

Nuclear triiodothyronine receptors in rabbit heart

International Nuclear Information System (INIS)

Banerjee, S.K.; Ulrich, J.M.; Kaldor, G.J.

1986-01-01

Nuclear triiodothyronine receptors from rat liver have been characterized in detail by several investigators. However, little work has been done in this area using heart tissue. In this study they examined and characterized the triiodothyronine binding in rabbit hearts. Nuclei have been prepared from ventricular muscle cells of normal and thyrotoxic rabbits as well as from atrial muscle cells of normal rabbit. Hearts were perfused with a minimum essential medium containing collagenase and bovine serum albumin. Myocardial cells were isolated and then disrupted by sonication and washing with a Triton X-100 buffer solution. A discontinuous sucrose density gradient was then used to isolate the mycoardial nuclei. Radiolabelled triiodothyronine (T 3 ) binding to nuclei was examined using conditions described by established procedures. Scatchard analysis of the binding data yields maximum binding capacity (B/sub max/) of 0.17 +/- 0.2 pmol/mg DNA and apparent dissociation constant (K/sub d/) of 400 +/- 50 pM for normal heart T 3 -receptors. The apparent capacity for T 3 binding is approximately 40% greater in myocardial nuclei prepared from hearts of hyperthyroid rabbits. The binding capacity of atrial muscle nuclei is about fourfold lower than ventricular cell nuclei. The results suggest that binding capacity for T 3 -receptor in the atrium is considerably lower than that found in the ventricle

Experimental corneal calcification, hydration and /sup 45/Ca uptake in rabbit corneas incubated in vitro

Energy Technology Data Exchange (ETDEWEB)

Obenberger, J [Ceskoslovenska Akademie Ved, Prague. Oftalmologicka Laborator; Dobiasova, M; Babicky, A [Ceskoslovenska Akademie Ved, Prague. Isotopova Laborator Biologickych Ustavu

1974-07-01

Experimental corneal calcification could easily be produced by a combination of corneal injury (perfusion of the anterior chamber of the eye with a solution of potassium permanganate) amd dihydrotachysterol (DHT) treatment. Rabbit corneas with induced calcification as well as corneas of three additional groups of rabbits, i.e. those treated with permanganate or DHT only and control animals were incubated for two hours in a medium containing /sup 45/Ca. An increased uptake of /sup 45/Ca into the cornea was found in the group of rabbits receiving DHT only. Potassium cyanide added to the incubation medium did not affect corneal hydration nor the final activity of the incubated corneas. (auth)

Locating Mandibular Foramen in Children with Mandibular Retrognathism in Mixed Dentition

Directory of Open Access Journals (Sweden)

Mehrsa Paryab

2015-06-01

Full Text Available Background and aims. One of the most common reasons forthe inferior alveolar nerve block anesthesia failure is the variation in mandibular foramen location. The aim of this study was to assess the location of mandibular foramen in chil-dren with mandibular retrognathism in comparison to children with normal skeletal occlusion in the mixed dentition. Materials and methods. One hundred and twenty panoramic radiographs of patients in mixed dentition period, undergo-ing orthodontic treatment, were selected based on inclusion criteria, skeletal occlusion and stage of dental development. The radiographs were divided into two groups: I: 60 panoramic radiographs of patients with normal skeletal occlusion (15 in each of the Hellman dental age stages; II: 60 panoramic radiographs of patients with mandibular retrognathism (15 in each of the Hellman dental age stages. The radiographs were traced and the linear distance from the mandibular foramen to the borders of the mandibular ramus and its angular position were identified. The measurements were compared between the two groups and among the four dental age groups by t-test, ANOVA and post hoc tests. Results. No statistically significant differences werefound between the patients with normal skeletal occlusion and patients with mandibular retrognathism (P>0.05. Statistical tests showed significant differences in the vertical location of mandibu-lar foramen and gonial angle between the four dental age groups (P<0.05. Conclusion. Mandibular retrognathism does not have a significant impact on the location of the mandibular foramen in the mixed dentition period. The child’s dental age would be considered in the localization of the mandibular foramen.

Biotransformation of hydralazine (HDZ) in monolayer cultures of rabbit hepatocytes

International Nuclear Information System (INIS)

McQueen, C.A.; Rosado, R.R.

1990-01-01

Adverse reactions to HDZ have been associated with the acetylator polymorphism; slow acetylators are more likely to develop HDZ-induced lupus erythematosus. In studying the role of this polymorphism in susceptibility to HDZ toxicity, the biotransformation of HDZ was investigated in rabbit hepatocytes. New Zealand white rabbits, like humans, are classified as rapid or slow acetylators. Heptocytes were isolated from rapid acetylator rabbits by collagenase perfusion. Monolayer cultures were initiated and exposed to 14 C-HDZ. Since HDZ is unstable at neutral pH, parallel incubations were done in the absence of cells. Metabolites in the media were determined by reverse phase HPLC. Phthalazine (P), phthalazinone (PZ), triazoloph-thalazine (TP), methyl TP (MTP) and 3-hydroxy MTP were identified. In the absence of cells, more TP was formed than MTP, probably resulting from reaction of HDZ with components in the medium. In the presence of cells, there was a three-fold increase in MTP, while the amount of TP was relatively constant. Only trace amounts of P, PZ 3-hydroxy MTP were detected. These data indicate that monolayer cultures of rapid acetylator rabbit hepatocytes were capable of metabolizing HDZ with acetylation playing a major role. These studies are being extended to cells from slow acetylator rabbits

Phase dependency of electrotonic spread of hyperpolarizing current pulses in the rabbit sinoatrial node

NARCIS (Netherlands)

Duivenvoorden, J. J.; Bouman, L. N.; Bukauskas, F. F.; Opthof, T.; Jongsma, H. J.

1990-01-01

Electrotonic current spread in the SA node of the rabbit was measured by means of hyperpolarizing current pulses (1 to 10 microA, 60 ms), which were injected intracellularly through a K(+)-perfused suction electrode. The pulses were applied at the beginning, middle or end of the diastolic

Impaired atrial electromechanical function and atrial fibrillation promotion in alloxan-induced diabetic rabbits.

Science.gov (United States)

Fu, Huaying; Liu, Changle; Li, Jian; Zhou, Changyu; Cheng, Lijun; Liu, Tong; Li, Guangping

2013-01-01

Diabetes mellitus (DM) is an independent risk factor for atrial fibrillation (AF). However, the underlying mechanisms are still not clearly elucidated. The aim of this study was to evaluate the atrial electromechanical function, atrial electrophysiological changes and AF inducibility in alloxan-induced diabetic rabbits. In 8 alloxan-induced diabetic rabbits and 8 controls, we evaluated atrial electromechanical function by tissue Doppler imaging. Isolated Langendorff-perfused rabbit hearts were prepared to measure atrial refractory effective period (AERP) and its dispersion (AERPD), interatrial conduction time (IACT) and vulnerability to AF. Atrial interstitial fibrosis was evaluated by Sirius-Red staining. Compared with controls, left atrial lateral wall Pa'-start interval (Pastart) and right atrial wall Pastart were increased in diabetic rabbits. AERPD was increased and IACT was prolonged in diabetic rabbits. Inducibility of AF in diabetic group was significant higher than controls (6/8 vs. 1/8, p TEMA); left atrial lateral wall Papeak and TEMA, left atrial posterior wall TEMA, and IACT were correlated with atrial areas of fibrosis. Atrial electromechanical function is impaired in diabetic rabbits, and is associated with atrial fibrosis and interatrial electrical conduction delay.

Hepatic VX2 tumor after portal vein occlusion in rabbits: evaluation with DSA

International Nuclear Information System (INIS)

Qi Yueyong; Zou Liguang; Dai Shuhua; Zhang Qichuan; Chen Lin; Huang Xiaobing; Huan Guangqiang

2006-01-01

Objective: To study the value of DSA for hepatic vascular anatomy, and to evaluate the efficacy of portal vein occlusion in rabbits with hepatic VX2 tumor. Methods: Twenty New Zealand white rabbits were randomly divided into two groups with 10 in each group, including test group A and positive control group B of ham operation. For the test group A, portal branch ligation (PBL) was performed for the left external branch after 3 weeks of the tumor implantation to the left external lobe. Two weeks later, the DSA of hepatic artery and portal vein were performed in all of the rabbits. Results: The total displaying effectiveness of the branches of hepatic artery by DSA was better than that by vascular perfusion. There was hypovascular blood supply to hepatic artery implantation of the tumor in the test group A, comparing with that of the group B. Conclusion: DSA can clearly display special details of the hepatic vascular anatomy in rabbits, and play an important role in post-procedural evaluation of the portal vein occlusion in rabbits. (authors)

Anatomical Arrangement of the Subclavian Artery Branches in the Rabbit and European Hare

Directory of Open Access Journals (Sweden)

Maženský D.

2017-12-01

Full Text Available The aim of this study was to compare the anatomical arrangements of the branches arising from the subclavian arteries in the domesticated rabbit and hare. The study was carried out on ten adult rabbits and ten adult European hares using the corrosion cast technique. After the euthanasia, the vascular network was perfused with saline. The arterial system of the entire body was injected by Batson’s corrosion casting kit No. 17. After polymerization of the medium, the maceration was carried out in KOH solution. The arrangement of the origins of the branches of the bilateral subclavian arteries were more variable in the hare. The number of branches arising from the subclavian artery were more regular in the rabbit on the right side and in the hare on the left side. In the rabbit, we found in two cases, the origins of the branches of the left subclavian artery from the aortic arch. The anatomical found between the rabbit and the hare may possibly be associated with their different ways of life.

Radiologic study of mandibular foramen of mandibular prognathism by three-dimensional computed tomography

Energy Technology Data Exchange (ETDEWEB)

Lee, Seung Hun; Moon, Cheol Hyun; Im, Jeong Soo; Seo, Hwa Jeong [Graduate School of Public Health and Social Welfare, Gachon University of Medicine and Science, Incheon (Korea, Republic of)

2010-06-15

This study is aimed to evaluate the position of mandibular foramen of mandibular prognathism patients using 3-dimensional CT images in order to reduce the chance of an anesthetic failure of the mandibular nerve and to prevent the damage to the inferior alveolar nerve during the orthognathic surgery. The control group consist of 30 patients with class I occlusion. The experimental group consist of 44 patients with class III malocclusion. Three-dimensional computed tomography was used to evaluate the position of the mandibular foramina. The distance between mandibular plane and mandibular foramen, class I was 25.385 mm, class III was 23.628 mm. About the distance between occlusal plane and mandibular foramen, class I was 1.478 mm, class III was 5.144 mm. The distance between posterior border plan of mandibular ramus and mandibular foramen had not statistically significant. About the distance between sagittal plane of mandible and mandibular foramen did not also showed statistically significant. The result of this study could help the clinicians to apprehend more accurate anatomical locations of the foramina on the mandible with various facial skeletal types. Thereby to perform more accurate block anesthesia of the mandibular nerve and osteotomy with minimal nerve damage. In addition, this study could provide fundamental data for any related researches about the location of the mandibular foramina for other purposes.

Radiologic study of mandibular foramen of mandibular prognathism by three-dimensional computed tomography

International Nuclear Information System (INIS)

Lee, Seung Hun; Moon, Cheol Hyun; Im, Jeong Soo; Seo, Hwa Jeong

2010-01-01

This study is aimed to evaluate the position of mandibular foramen of mandibular prognathism patients using 3-dimensional CT images in order to reduce the chance of an anesthetic failure of the mandibular nerve and to prevent the damage to the inferior alveolar nerve during the orthognathic surgery. The control group consist of 30 patients with class I occlusion. The experimental group consist of 44 patients with class III malocclusion. Three-dimensional computed tomography was used to evaluate the position of the mandibular foramina. The distance between mandibular plane and mandibular foramen, class I was 25.385 mm, class III was 23.628 mm. About the distance between occlusal plane and mandibular foramen, class I was 1.478 mm, class III was 5.144 mm. The distance between posterior border plan of mandibular ramus and mandibular foramen had not statistically significant. About the distance between sagittal plane of mandible and mandibular foramen did not also showed statistically significant. The result of this study could help the clinicians to apprehend more accurate anatomical locations of the foramina on the mandible with various facial skeletal types. Thereby to perform more accurate block anesthesia of the mandibular nerve and osteotomy with minimal nerve damage. In addition, this study could provide fundamental data for any related researches about the location of the mandibular foramina for other purposes.

Electromechanical effects of bepridil on rabbit isolated hearts.

OpenAIRE

Anno, T.; Furuta, T.; Itoh, M.; Kodama, I.; Toyama, J.; Yamada, K.

1984-01-01

Electromechanical effects of a new antianginal agent, bepridil, on Langendorff-perfused rabbit hearts were compared with those of verapamil and lidocaine. Bepridil at concentrations above 2 X 10(-7)M caused a dose-related decrease in heart rate (HR), a prolongation of the atrio-His bundle conduction time (A-H interval) and a prolongation of the functional refractory period (FRP) of the atrioventricular (A-V) node. Similar changes in HR, A-H interval and the FRP of the A-V node were observed w...

The evaluation of anti-angiogenic treatment effects for implanted rabbit VX2 breast tumors using functional multi-slice spiral computed tomography (f-MSCT)

International Nuclear Information System (INIS)

Lei Zhen; Ma Heji; Xu Na; Xi Huanjiu

2011-01-01

Objective: Investigate the benefit of functional multi-slice spiral computed tomography (f-MSCT) perfusion imaging in the non-invasive assessment of targeted anti-angiogenesis therapy on an implanted rabbit VX2 breast tumor model. Method: 69 female pure New Zealand white rabbits were randomly assigned to one of the 4 groups and received treatment accordingly: control (saline), Endostar, neoadjuvant chemotherapy (Cyclophosphamide, Epirubicin and 5-Fluorouracil, CEF), combination therapy (Endostar and CEF). After 2 weeks of treatment, f-MSCT perfusion scannings were performed for all rabbits and information about blood flow (BF), blood volume (BV), mean transit time (MTT) and surface permeability (SP) was collected. After perfusion imaging, tumor tissues were sampled for immunohistochemistry and the Western blot test of VEGF protein expression. Results: (1) The VEGF expression level, measured by immunohistochemistry and Western blot, decreased by treatment group (control > Endostar > CEF > combination therapy). The same was true for the mean BF, BV, MTT and PS, which decreased from the control group to the combination therapy group gradually. The mean MTT level increased in reverse order from the control to the combination therapy group. The difference between any 2 groups on these measures was statistically significant (P < 0.05). (2) There was moderate positive correlation between VEGF expression and BE, BV, or PS level (P < 0.05) and a negative correlation between VEGF expression and MTT level for all 4 groups (P < 0.05). Conclusion: Therefore, f-MSCT can be used as a non-invasive approach to evaluate the effect of anti-angiogenic therapy for implanted rabbit VX2 breast tumors.

The evaluation of anti-angiogenic treatment effects for implanted rabbit VX2 breast tumors using functional multi-slice spiral computed tomography (f-MSCT)

Energy Technology Data Exchange (ETDEWEB)

Lei Zhen, E-mail: leizhen2004@163.com [Department of Anatomy, Chinese Medical University, No. 92, Beiermalu Road, Heping District, Shenyang, 110001 (China) and Department of Radiology, The First Hospital of Liaoning Medical College, No. 2, Wuduan, Renmin Street, Jinzhou, 121001 (China); Ma Heji, E-mail: maheji9831@sina.com [Department of Radiology, The First Hospital of Liaoning Medical College, No. 2, Wuduan, Renmin Street, Jinzhou, 121001 (China); Xu Na, E-mail: xuna821230@sohu.com [Department of Radiology, The First Hospital of Liaoning Medical College, No. 2, Wuduan, Renmin Street, Jinzhou, 121001 (China); Xi Huanjiu, E-mail: xihuanjiu2004@yahoo.cn [Anthropology Institute, Liaoning Medical College, No. 40, Sanduan, Songpo Rd, Jinzhou, 121001 (China)

2011-05-15

Objective: Investigate the benefit of functional multi-slice spiral computed tomography (f-MSCT) perfusion imaging in the non-invasive assessment of targeted anti-angiogenesis therapy on an implanted rabbit VX2 breast tumor model. Method: 69 female pure New Zealand white rabbits were randomly assigned to one of the 4 groups and received treatment accordingly: control (saline), Endostar, neoadjuvant chemotherapy (Cyclophosphamide, Epirubicin and 5-Fluorouracil, CEF), combination therapy (Endostar and CEF). After 2 weeks of treatment, f-MSCT perfusion scannings were performed for all rabbits and information about blood flow (BF), blood volume (BV), mean transit time (MTT) and surface permeability (SP) was collected. After perfusion imaging, tumor tissues were sampled for immunohistochemistry and the Western blot test of VEGF protein expression. Results: (1) The VEGF expression level, measured by immunohistochemistry and Western blot, decreased by treatment group (control > Endostar > CEF > combination therapy). The same was true for the mean BF, BV, MTT and PS, which decreased from the control group to the combination therapy group gradually. The mean MTT level increased in reverse order from the control to the combination therapy group. The difference between any 2 groups on these measures was statistically significant (P < 0.05). (2) There was moderate positive correlation between VEGF expression and BE, BV, or PS level (P < 0.05) and a negative correlation between VEGF expression and MTT level for all 4 groups (P < 0.05). Conclusion: Therefore, f-MSCT can be used as a non-invasive approach to evaluate the effect of anti-angiogenic therapy for implanted rabbit VX2 breast tumors.

Blood perfusion and pH monitoring in organs by laser-induced fluorescence spectroscopy

Science.gov (United States)

Vari, Sandor G.; Papazoglou, Theodore G.; Pergadia, Vani R.; Stavridi, Marigo; Snyder, Wendy J.; Papaioannou, Thanassis; Duffy, J. T.; Weiss, Andrew B.; Thomas, Reem; Grundfest, Warren S.

1994-01-01

Sensitivity of laser-induced fluorescence spectroscopy (LIFS) in detecting a change in tissue pH, and blood perfusion was determined. Rabbits were anesthetized, paralyzed, and mechanically ventilated. The arterial and venous blood supplies of the kidney were isolated and ligated to alter the perfusion. The femoral artery was cannulated to extract samples for blood gas analysis. A 308-nm XeCl was used as an excitation source. A 600 micrometers core diameter fiber was used for fluorescence acquisition, and the spectra analyzed by an optical multichannel analyzer (EG & G, OMA III). the corresponding intensity ratio R equals INADH / ICOLL was used as an index for respiratory acidosis. Blood perfusion was assessed using the following algorithm: (IELAS minus ICOLL) divided by (INADH minus ICOLL). The intensity ratio linearly decreased with the reduction of blood perfusion. When we totally occluded the artery the ratio decreased tenfold when compared to the ratio of a fully perfused kidney. Results of monitoring blood acidosis by laser-induced fluorescence spectroscopy shows a significant trend between pH and intensity ratio. Since all the slopes were negative, there is an obvious significant correlation between the pH and NADH.COLLAGEN RATIO. Blue-light-induced fluorescence measurements and ratio fluorometry is a sensitive method for monitoring blood perfusion and acidity or alkalinity of an organ.

Release of Tissue-specific Proteins into Coronary Perfusate as a Model for Biomarker Discovery in Myocardial Ischemia/Reperfusion Injury

DEFF Research Database (Denmark)

Cordwell, Stuart; Edwards, Alistair; Liddy, Kiersten

2012-01-01

-rich plasma, in which the wide dynamic range of the native protein complement hinders classical proteomic investigations. We employed an ex vivo rabbit model of myocardial ischemia/reperfusion (I/R) injury using Langendorff buffer perfusion. Nonrecirculating perfusate was collected over a temporal profile...... reperfusion post-15I. Proteins released during irreversible I/R (60I/60R) were profiled using gel-based (2-DE and one-dimensional gel electrophoresis coupled to liquid chromatography and tandem mass spectrometry; geLC–MS) and gel-free (LC–MS/MS) methods. A total of 192 tissue-specific proteins were identified...... release using ex vivo buffer perfused tissue to limit the presence of obfuscating plasma proteins may identify candidates for further study in humans....

The effects of orthognathic surgery on mandibular movements in patients with mandibular prognathism

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Sinobad Vladimir

2012-01-01

Full Text Available Introduction. Mandibular prognathism, one of the most severe dentofacial deformities, affects the person’s appearance, psychological health and the quality of life in the most sensitive age period. Objective. The aim of this study was to evaluate the effects of sagittal split ramus osteotomy on the range of mandibular border movements in the early postoperative period. Methods. The study was conducted on 20 patients, of mean age 20.8 years, with mandibular prognathism. All patients included in this study were operated on by bilateral sagittal spliting ramus osteotomy according to Obwegeser and Dal Pont followed by mandibular immobilization during eight weeks. In all patients mandibular border movements were recorded before and six months after surgery using the computerized pantograph Arcus-Digma (KaVo EWL GmbH, Leutkirch, Germany. Results. The analysis of the chosen kinematic parameters revealed that sagittal split ramus osteotomy followed by eight weeks of mandibular immobilization had severe effects on the mouth opening. Six months after surgery the range of maximal mouth opening decreased for approximately 13.9 mm in relation to the preoperative stage. On the contrary, the ranges of maximal protrusion and the border of laterotrusive excursions increased significantly after surgery. Conclusion. In patients with mandibular prognathism where enormous mandibular growth was the main causal factor of the deformity, the sagittal split ramus osteotomy yielded good results. The rigid fixation of bone fragments and reduced period of mandibular immobilization followed by appropriate physical therapy could considerably contribute to a more rapid recovery of mandibular kinematics in the postoperative period.

Synergism between endotoxin priming and exotoxin challenge in provoking severe vascular leakage in rabbit lungs.

Science.gov (United States)

Schütte, H; Rosseau, S; Czymek, R; Ermert, L; Walmrath, D; Krämer, H J; Seeger, W; Grimminger, F

1997-09-01

Lipopolysaccharides (LPS) of gram-negative bacteria prime rabbit lungs for enhanced thromboxane-mediated vasoconstriction upon subsequent challenge with the exotoxin Escherichia coli hemolysin (HlyA) (Walmrath et al. J. Exp. Med. 1994;180:1437-1443). We investigated the impact of endotoxin priming and subsequent HlyA challenge on lung vascular permeability while maintaining constancy of capillary pressure. Rabbit lungs were perfused in a pressure-controlled mode in the presence of the thromboxane receptor antagonist BM 13.505, with continuous monitoring of flow. Perfusion for 180 min with 10 ng/ml LPS did not provoke vasoconstriction or alteration of capillary filtration coefficient (Kfc) values. HlyA (0.021 hemolytic units/ml) induced thromboxane release and a transient decrease in perfusion flow in the absence of significant changes in Kfc. Similar results were obtained when LPS and HlyA were coapplied simultaneously. However, when the HlyA challenge was undertaken after 180 min of LPS priming, a manifold increase in Kfc values was noted, with concomitant severe lung edema formation, although capillary pressure remained unchanged. Thus, endotoxin primes the lung vasculature to respond with a severe increase in vascular permeability to a subsequent low-dose application of HlyA. Such synergism between endotoxin priming and exotoxin challenge in provoking lung vascular leakage may contribute to the pathogenesis of respiratory failure in sepsis and severe lung infection.

Repair of segmental bone defect using Totally Vitalized tissue engineered bone graft by a combined perfusion seeding and culture system.

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Lin Wang

Full Text Available BACKGROUND: The basic strategy to construct tissue engineered bone graft (TEBG is to combine osteoblastic cells with three dimensional (3D scaffold. Based on this strategy, we proposed the "Totally Vitalized TEBG" (TV-TEBG which was characterized by abundant and homogenously distributed cells with enhanced cell proliferation and differentiation and further investigated its biological performance in repairing segmental bone defect. METHODS: In this study, we constructed the TV-TEBG with the combination of customized flow perfusion seeding/culture system and β-tricalcium phosphate (β-TCP scaffold fabricated by Rapid Prototyping (RP technique. We systemically compared three kinds of TEBG constructed by perfusion seeding and perfusion culture (PSPC method, static seeding and perfusion culture (SSPC method, and static seeding and static culture (SSSC method for their in vitro performance and bone defect healing efficacy with a rabbit model. RESULTS: Our study has demonstrated that TEBG constructed by PSPC method exhibited better biological properties with higher daily D-glucose consumption, increased cell proliferation and differentiation, and better cell distribution, indicating the successful construction of TV-TEBG. After implanted into rabbit radius defects for 12 weeks, PSPC group exerted higher X-ray score close to autograft, much greater mechanical property evidenced by the biomechanical testing and significantly higher new bone formation as shown by histological analysis compared with the other two groups, and eventually obtained favorable healing efficacy of the segmental bone defect that was the closest to autograft transplantation. CONCLUSION: This study demonstrated the feasibility of TV-TEBG construction with combination of perfusion seeding, perfusion culture and RP technique which exerted excellent biological properties. The application of TV-TEBG may become a preferred candidate for segmental bone defect repair in orthopedic and

Mandibular tori are associated with mechanical stress and mandibular shape.

Science.gov (United States)

Cortes, Arthur Rodriguez Gonzalez; Jin, Zhaoyu; Morrison, Matthew Daniel; Arita, Emiko Saito; Song, Jun; Tamimi, Faleh

2014-11-01

The influence of mechanical stimulation on the formation of torus mandibularis (TM) is still poorly understood. We sought to understand the etiology of TMs by investigating the role of parafunctional activity and mandibular morphology on the formation of TMs. We designed a case-control study for patients attending the dental clinic of the present study (University of São Paulo School of Dentistry, São Paulo, SP, Brazil). Patients presenting with TMs were defined as cases, and those without TMs were defined as controls. Finite element analysis (FEA) was used in 3-dimensional mandibular models to examine the stress distribution in the mandibles with and without TMs. In addition, the associations of mandibular arch shape, mandibular cortical index, and parafunctional activity with the presence of T were assessed using odds ratio analysis. A total of 10 patients with TMs and 37 without TMs were selected (22 men and 25 women, mean age 54.3 ± 8.4 years). FEA showed a stress concentration in the region in which TMs form during simulation of parafunctional activity. The radiographic assessment showed that those with TMs were more likely to have a square-shaped mandible with sharp angles (P = .001) and a normal mandibular cortex (P = .03). The subjects without TMs had a round-shaped mandible with obtuse angles and an eroded mandibular cortex. Parafunctional activity could be causing the formation of TMs by concentrating mechanical stress in the region in which TMs usually form. Thus, mandibular geometries that favor stress concentration, such as square-shaped mandibles, will be associated with a greater prevalence of TMs. Copyright © 2014 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

Radiological study of the mandibular fractures

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Kim, Ju Won; Kim, Kyoung A; Koh, Kwang Jun [Department of Oral and Maxillofacial Radiology, School of Dentistry, and Institute of Oral Bio Science, Chonbuk National University, Jeonju (Korea, Republic of)

2009-06-15

To classify and evaluate mandibular fractures. The author classified mandibular fractures of 284 patients who were referred to the Chonbuk National University Dental Hospital during the period from March 2004 to June 2007. This study was based on the conventional radiographs as well as computed tomographs which were pertained to the 284 patients who have had the mandibular fractures including the facial bone fractures. And mandibular fractures were classified with respect to gender, age, site and type of the fractures. More frequently affected gender with mandibular fracture was male with the ratio of 3.3 : 1. The most frequently affected age with mandibular fracture was third decade (38%), followed by fourth decade (16%), second decade (15%), fifth decade (11%), sixth decade (7%), seventh decade (5%), eighth decade (4%), first decade (4%), and ninth decade (0.3%). The most frequent type of mandibular fracture was single fracture (58%), followed by double fracture (39%), triple fracture (3%). The most common site of mandibular fracture was mandibular condyle as 113 cases (27.7%) and the next was mandibular symphysis as 109 cases (26.7%), mandibular angle as 103 cases (25.3%), mandibular body as 83 cases (20.3%) in order. The sum of fracture sites were 408 sites and there were 1.4 fracture sites per one patient. The number of mandible fractures accompanied with facial bone fractures were 41 cases (14.4%). The results showed the most frequent type and common site of mandibular fracture was single fracture and mandibular condyle respectively.

Radiological study of the mandibular fractures

International Nuclear Information System (INIS)

Kim, Ju Won; Kim, Kyoung A; Koh, Kwang Jun

2009-01-01

To classify and evaluate mandibular fractures. The author classified mandibular fractures of 284 patients who were referred to the Chonbuk National University Dental Hospital during the period from March 2004 to June 2007. This study was based on the conventional radiographs as well as computed tomographs which were pertained to the 284 patients who have had the mandibular fractures including the facial bone fractures. And mandibular fractures were classified with respect to gender, age, site and type of the fractures. More frequently affected gender with mandibular fracture was male with the ratio of 3.3 : 1. The most frequently affected age with mandibular fracture was third decade (38%), followed by fourth decade (16%), second decade (15%), fifth decade (11%), sixth decade (7%), seventh decade (5%), eighth decade (4%), first decade (4%), and ninth decade (0.3%). The most frequent type of mandibular fracture was single fracture (58%), followed by double fracture (39%), triple fracture (3%). The most common site of mandibular fracture was mandibular condyle as 113 cases (27.7%) and the next was mandibular symphysis as 109 cases (26.7%), mandibular angle as 103 cases (25.3%), mandibular body as 83 cases (20.3%) in order. The sum of fracture sites were 408 sites and there were 1.4 fracture sites per one patient. The number of mandible fractures accompanied with facial bone fractures were 41 cases (14.4%). The results showed the most frequent type and common site of mandibular fracture was single fracture and mandibular condyle respectively.

Anatomical Comparison of the Renal Arteries in the Rabbit and European Hare

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Flešárová S.

2017-12-01

Full Text Available The aim of this paper was to compare the level of origin of the renal arteries in the rabbit and hare. The study was carried out on ten adult rabbits and ten adult European hares using the corrosion cast technique. After the euthanasia, the vascular network was perfused with saline. Batson’s corrosion casting kit No. 17 was used as a casting medium. After polymerization of the medium, the maceration was carried out in KOH solution. We found variable levels of the origin of renal arteries in the rabbit, in the hare and between both species. In the rabbit, the right renal artery originated at the level of the second lumbar vertebra in 70 % of the cases and at the level of the first lumbar vertebra in 30 % of the cases, and the left-sided renal artery originated in 60 % of the cases at the level of the second lumbar vertebra and at the level of the third lumbar vertebra in 40 % of the cases. In the hare, the bilateral renal arteries originated at the level of the second lumbar vertebra. According to the results, it can be concluded that the origin level of the renal arteries from the abdominal aorta is more variable in the domesticated rabbit in comparison with the hare.

Active Oxygen Metabolites and Thromboxane in Phorbol Myristate Acetate Toxicity to the Isolated, Perfused Rat Lung.

Science.gov (United States)

Carpenter, Laurie Jean

When administered intravenously or intratracheally to rats, rabbits and sheep, phorbol myristate acetate (PMA) produces changes in lung morphology and function are similar to those seen in humans with the adult respiratory distress syndrome (ARDS). Therefore, it is thought that information about the mechanism of ARDS development can be gained from experiments using PMA-treated animals. Currently, the mechanisms by which PMA causes pneumotoxicity are unknown. Results from other studies in rabbits and in isolated, perfused rabbit lungs suggest that PMA-induced lung injury is mediated by active oxygen species from neutrophils (PMN), whereas studies in sheep and rats suggest that PMN are not required for the toxic response. The role of PMN, active oxygen metabolites and thromboxane (TxA_2) in PMA-induced injury to isolated, perfused rat lungs (IPLs) was examined in this thesis. To determine whether PMN were required for PMA to produce toxicity to the IPL, lungs were perfused for 30 min with buffer containing various concentrations of PMA (in the presence or absence of PMN). When concentrations >=q57 ng/ml were added to medium devoid of added PMN, perfusion pressure and lung weight increased. When a concentration of PMA (14-28 ng/ml) that did not by itself cause lungs to accumulate fluid was added to the perfusion medium containing PMN (1 x 10 ^8), perfusion pressure increased, and lungs accumulated fluid. These results indicate that high concentrations of PMA produce lung injury which is independent of PMN, whereas injury induced by lower concentrations is PMN-dependent. To examine whether active oxygen species were involved in mediating lung injury induced by PMA and PMN, lungs were coperfused with the oxygen radical scavengers SOD and/or catalase. Coperfusion with either or both of these enzymes totally protected lungs against injury caused by PMN and PMA. These results suggest that active oxygen species (the hydroxyl radical in particular), mediate lung injury in

Morphometric and ultrastructural studies of the effect of infrared laser on rabbit temporo-mandibular joint fibroblasts

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Ricardo Cornejo Uribe

2009-06-01

Full Text Available The infrared laser beams has been successfully used in joint lesions treatment due to its analgesic anti inflamatory and healing action, and on a cellular level, inducing an accentuated synthesis of ATP, activating cellular proliferation and collagen synthesis. Samples of normal-control and irradiated tissue from temporo-mandibular joint disc of rabbit, were obtained, with daily doses of 2 joules/cm²during 10 consecutive days. They were prepared for transmission electronic microscopy.Transmission electronic micrographs of normal and irradiated fibroblasts were obtained with final increase of 11.500 X for morphometric studies with the purpose of quantifying the volumetric fractions of the cellular components pertaining to the mentioned cellular types. Volumetric fractions of the quoted cell corresponding to nucleus, cytoplasm, rough endoplasmatic reticule, eu and heterochromatin were evaluated. In the same manner, the nucleus - cytoplasmatic relation and the area of each cellular type were quantified. The results derived from the morphometric comparative study between the normal and irradiated fibroblasts indicated that there were significant differences with respect to the volumetric fractions of euchromatin and heterochromatin and fundamentally in the cellular areas of both types. On the other hand, the rest of quantified parameters remained constant. It could be concluded that the cellular function reflected in collagen synthesis and secretion remained constant in both cellular types. However, by means of infrared laser stimulations, this fibroblast facilitated protein synthesis, due to high percentage of transcriptionally active euchromatine.O raio laser infravermelho tem sido usado com sucesso no tratamento de lesoes articulares por sua ação analgesica, antinflamatoria e cicatrizante e, ao nivel celular, induzindo acentuada síntese de ATP, ativando a proliferação celular e a síntese do colágeno. Foram obtidas amostras do disco da

Alloxan-induced diabetes reduces sarcolemmal Na+-K+ pump function in rabbit ventricular myocytes.

Science.gov (United States)

Hansen, Peter S; Clarke, Ronald J; Buhagiar, Kerrie A; Hamilton, Elisha; Garcia, Alvaro; White, Caroline; Rasmussen, Helge H

2007-03-01

The effect of diabetes on sarcolemmal Na(+)-K(+) pump function is important for our understanding of heart disease associated with diabetes and design of its treatment. We induced diabetes characterized by hyperglycemia but no other major metabolic disturbances in rabbits. Ventricular myocytes isolated from diabetic rabbits and controls were voltage clamped and internally perfused with the whole cell patch-clamp technique. Electrogenic Na(+)-K(+) pump current (I(p), arising from the 3:2 Na(+)-to-K(+) exchange ratio) was identified as the shift in holding current induced by Na(+)-K(+) pump blockade with 100 micromol/l ouabain in most experiments. There was no effect of diabetes on I(p) recorded when myocytes were perfused with pipette solutions containing 80 mmol/l Na(+) to nearly saturate intracellular Na(+)-K(+) pump sites. However, diabetes was associated with a significant decrease in I(p) measured when pipette solutions contained 10 mmol/l Na(+). The decrease was independent of membrane voltage but dependent on the intracellular concentration of K(+). There was no effect of diabetes on the sensitivity of I(p) to extracellular K(+). Pump inhibition was abolished by restoration of euglycemia or by in vivo angiotensin II receptor blockade with losartan. We conclude that diabetes induces sarcolemmal Na(+)-K(+) pump inhibition that can be reversed with pharmacological intervention.

Roentgenographic study of the mandibular canal

International Nuclear Information System (INIS)

Ahn, Hyung Kyu

1980-01-01

The mandibular canal must be considered carefully during the surgical treatment, especially surgical extraction of the impacted tooth and intraosseous implant, because it contains the important inferior alveolar nerve and vessels. The author investigated the curvature of the mandibular canal and its relation to the mandibular molars and positional relation between the mental foramen and the mandibular premolars in orthopantomogram. The materials consisted of 441 orthopantomograms divided four groups; Group I consisted of 56 males and 44 females from 1 to 6 years of age, Group II consisted of 58 males and 45 females from 7 to 12 years of age, Group III consisted of 65 males and 33 females from 13 to 18 years of age, Group IV consisted of 86 males and 54 females over 19 years of age. The results were as followings; 1. The curvature of mandibular canal was 144.50 .deg. in Group II, 148.11 .deg. in Group III, 147.33 .deg. in Group IV. 2. The curvature of mandibular canal was located most frequently on the area between mandibular 1st molar and mandibular 2nd molar in Group I (42%) and on the mandibular 2nd molar area in Group II (54%), Group III (59%), Group IV (53%). 3. The position of mental foramen was most frequently below the mandibular 1st premolar in Group I (58%), between the mandibular 1st premolar and the 2nd premolar in Group II (62%), Group III (47%), and below the mandibular 2nd premolar in Group IV (58%).

Complaints related to mandibular function impairment after closed treatment of fractures of the mandibular condyle

NARCIS (Netherlands)

Niezen, E. T.; Bos, R. R. M.; de Bont, L. G. M.; Stegenga, B.; Dijkstra, P. U.

This study analysed the relationship between complaints and mandibular function after closed treatment of fractures of the mandibular condyle in a prospective study. In a I-year follow-up, complaints were assessed during physical examination and function was assessed using the mandibular function

[Mandibular-driven simultaneous maxillo-mandibular distraction for hemifacial microsomia with rapid prototyping technology].

Science.gov (United States)

Gao, Quan-Wen; Song, Hui-Feng; Xu, Ming-Huo; Liu, Chun-Ming; Chai, Jia-Ke

2013-11-01

To explore the clinical application of mandibular-driven simultaneous maxillo-mandihular distraction to correct hemifacial microsomia with rapid prototyping technology. The patient' s skull resin model was manufactured with rapid prototyping technology. The osteotomy was designed on skull resin model. According to the preoperative design, the patients underwent Le Fort I osteotomy and mandibular ramus osteotomy. The internal mandible distractor was embedded onto the osteotomy position. The occlusal titanium pin was implanted. Distraction were carried out by mandibular-driven simultaneous maxillo-mandihular distraction 5 days after operation. The distraction in five patients was complete as designed. No infection and dysosteogenesis happened. The longest distance of distraction was 28 mm, and the shortest distance was 16 mm. The facial asymmetry deformity was significantly improved at the end of distraction. The ocelusal plane of patients obviously improved. Rapid prototyping technology is helpful to design precisely osteotomy before operation. Mandibular-driven simultaneous maxillo-mandibular distraction can correct hemifacial microsomia. It is worth to clinical application.

Luminal and basolateral uptake of insulin in isolated perfused, proximal tubules

International Nuclear Information System (INIS)

Nielsen, S.; Nielsen, J.T.; Christensen, E.I.

1987-01-01

The present study was performed to quantitate compare the luminal and the peritubular uptake of 125 I-insulin in isolated, perfused, proximal tubules from rabbit kidneys. 125 I-insulin was added in physiological concentrations to either the perfusate or the bath fluid for 30 min. The luminal uptake in 30 min averaged 0.76 pg/mm at physiological concentrations and 18.0 pg/mm at high insulin concentrations. About 15-41% of the absorbed insulin was digested and 125 I-insulin at physiological and high concentrations in the bath was 0.136 and 0.318 pg, respectively. The data indicates that insulin is bound/absorbed at the basolateral membranes both by a saturable specific mechanism and a nonspecific, nonsaturable mechanism. The basolateral absorption constituted 15.2 and 1.8% of the total tubular extraction of insulin at physiological and high insulin concentrations, respectively. Electron microscope autoradiography showed that, after luminal as well as basolateral endocytosis, insulin was exclusively accumulated in endocytic vacuoles and lysosomes

Origin Level of the Ventral Branches of the Abdominal Aorta in the Rabbit and European Hare

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Maženský D.

2017-06-01

Full Text Available The aim of this research was to describe the level of origin of the branches originating from the ventral surface of the abdominal aorta in the rabbit and hare. The study was carried out on ten adult rabbits and ten adult European hares using the corrosion cast technique. After euthanasia, the vascular network was perfused with saline. Batson’s corrosion casting kit No. 17 was used as a casting medium. After polymerization of the medium, the maceration was carried out in a KOH solution. We found variable levels of the origin of the celiac, cranial mesenteric and caudal mesenteric arteries in both species. In the rabbit, the celiac artery originated in the majority of cases at the cranial end of the first lumbar vertebra and in the hare at the middle part of the vertebral body of the same vertebra. The cranial mesenteric artery in the rabbit originated predominantly at the level of the first lumbar vertebra and in the hare at the level of the second lumbar vertebra. In the rabbit, the caudal mesenteric artery originated mainly at the level of the sixth lumbar vertebra and in the hare, at the level of the fifth lumbar vertebra. We concluded that there were higher variabilities of the origins of the ventral branches of the abdominal aorta in domesticated rabbit in comparison with the European hare.

Radiological classification of mandibular fractures

International Nuclear Information System (INIS)

Mihailova, H.

2009-01-01

Mandibular fractures present the biggest part (up to 97%) of the facial bone fractures. Method of choice for diagnosing of mandibular fractures is conventional radiography. The aim of the issue is to present an unified radiological classification of mandibular fractures for the clinical practice. This classification includes only those clinical symptoms of mandibular fracture which could be radiologically objectified: exact anatomical localization (F1-F6), teeth in fracture line (Ta,Tb), grade of dislocation (D I, D II), occlusal disturbances (O(+), O(-)). Radiological symptoms expressed by letter and number symbols are systematized in a formula - FTDO of mandibular fractures similar to TNM formula for tumours. FTDO formula expresses radiological diagnose of each mandibular fracture but it doesn't include neither the site (left or right) of the fracture, nor the kind and number of fractures. In order to express topography and number of fractures the radiological formula is transformed into a decimal fraction. The symbols (FTD) of right mandible fracture are written in the numerator and those of the left site - in the denominator. For double and multiple fractures between the symbols for each fracture we put '+'. Symbols for occlusal disturbances are put down opposite, the fractional line. So topographo-anatomical formula (FTD/FTD)xO is formed. In this way the whole radiological information for unilateral, bilateral, single or multiple fractures of the mandible is expressed. The information in the radiological topography anatomic formula, resp. from the unified topography-anatomic classification ensures a quick and exact X-ray diagnose of mandibular fracture. In this way contributes to get better, make easier and faster X-ray diagnostic process concerning mandibular fractures. And all these is a precondition for prevention of retardation of the diagnosis mandibular fracture. (author)

[Temporo-mandibular joint. Morpho-functional considerations].

Science.gov (United States)

Scutariu, M D; Indrei, Anca

2004-01-01

The temporo-mandibular joint is distinguished from most other synovial joints of the body by two features: 1. the two jointed components carry teeth whose position and occlusion introduce a very strong influence on the movements of the temporo-mandibular joint and 2. its articular surfaces are not covered by hyaline cartilage, but by a dense, fibrous tissue. This paper describes the parts of the temporo-mandibular joint: the articular surfaces (the condylar process of the mandible and the glenoid part of the temporal bone), the fibrocartilaginous disc which is interposed between the mandibular and the temporal surface, the fibrous capsule of the temporo-mandibular joint and the ligaments of this joint. All these parts present a very strong adaptation at the important functions of the temporo-mandibular joint.

Femoral perfusion after pulsed electromagnetic field stimulation in a steroid-induced osteonecrosis model.

Science.gov (United States)

Ikegami, Akira; Ueshima, Keiichiro; Saito, Masazumi; Ikoma, Kazuya; Fujioka, Mikihiro; Hayashi, Shigeki; Ishida, Masashi; Fujiwara, Hiroyoshi; Mazda, Osam; Kubo, Toshikazu

2015-07-01

This study was designed to evaluate femoral perfusion after pulsed electromagnetic field (PEMF) stimulation in a steroid-induced osteonecrosis rabbit model by dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). Steroid-induced osteonecrosis was produced by single intramuscular injection of methylprednisolone in 15 rabbits. Eight rabbits underwent PEMF stimulation (PEMF group) and seven did not (control group). DCE-MRI was performed before PEMF stimulation, immediately before steroid administration, and 1, 5, 10, and 14 days after steroid administration. Regions of interest were set in the bilateral proximal femora. Enhancement ratio (ER), initial slope (IS), and area under the curve (AUC) were analyzed. ER, IS, and AUC in the control group significantly decreased after steroid administration compared with before administration (P<0.05). In PEMF group, IS significantly decreased; however, ER and AUC showed no significant differences after steroid administration compared with before. ER and IS in PEMF group were higher than in control group until 10th day, and AUC was higher until 5th day after steroid administration (P<0.05). PEMF stimulation restrains the decrease in blood flow after steroid administration. © 2015 Wiley Periodicals, Inc.

Observation of positional relation between mandibular third molars and the mandibular canal on limited cone beam computed tomography

International Nuclear Information System (INIS)

Hashizume, Atsuko; Nakagawa, Yoichi; Ishii, Hisako; Kobayashi, Kaoru

2004-01-01

We describe the preoperative use of limited cone beam computed tomography (CT) with a dental CT scanner for the assessment of mandibular third molars before extraction. Cone beam CT provides 42.7-mm-high and 30-mm-wide rectangular solid images, with a resolution of less than 0.2 mm. The positional relationship between the mandibular third molars and the mandibular canal was examined by dental CT. Sixty-eight lower third molars of 62 patients whose teeth were superimposed on the mandibular canal on periapical or panoramic radiographs were studied. Dental CT scans clearly demonstrated the positional relationship between the mandibular canal and the teeth. The mandibular canal was located buccally to the roots of 16 teeth, lingually to the roots of 27 teeth, inferiorly to the roots of 23 teeth, and between the roots of 2 teeth. The presence of bone between the mandibular canal and the teeth was not noted in 7 of 16 buccal cases, 24 of 27 lingual cases, and 10 of 23 inferior cases on dental CT scans, suggesting that the canal was in contact with the teeth. Fifty-nine of the 68 mandibular third molars were surgically removed, and postoperative transient hypoesthesia occurred in 4 patients. Dental CT scans showed no bone between the mandibular canal and the teeth in all 4 patients. Hypoesthesia was not related to the bucco-lingual location of the mandibular canal or to the extent of bone loss between the canal and the teeth. However, hypoesthesia did not occur in patients with bone between the mandibular canal and the teeth. Thus, information on the distance between the canal and teeth on dental CT scans was useful for predicting the risk of inferior alveolar nerve damage. Because of its high resolution and low radiation dose, cone beam CT was useful for examination before mandibular third molar surgery. (author)

[Effects of extract of Buddleja officinalis on prevention of dry eye in castrated rabbits].

Science.gov (United States)

Peng, Qing-Hua; Yao, Xiao-lei; Wu, Quan-long; Chen, Mei

2008-11-01

To assess the preventive effects of extract of Buddleja officinalis on dry eye in castrated rabbits and to discuss the mechanism of these effects. It was a experimental study. Thirty male rabbits were divided equally into normal group (A), disease group (B) and treatment group (C, D, and E). The dry eye model was established with orchiectomy (ORX) in Group B, C, D and E. Group C, D and E were gastrically perfused with single-dose or double-does of Buddleja officinalis extract or genistein for 30 days. All rabbits were examined with Schirmer I test (SIT). TGF-beta1, IL-1beta, TNF-alpha, Fas, FasL, Bax and bcl-2 were detected by immunohistochemistry. Morphological and ultrastructure changes were observed by electron microscopy. The SIT value of group C, D, E was significantly greater than that of group B (P Buddleja officinalis has a significant effect on the prevention of experimental dry eye in castrated male rabbits. The main components of extract of Buddleja officinalis are the flavonoids. The flavonoids display androgen-like activity. Therefore, it can adjust gonadal hormone level in vivo. As a result, it can inhibit local inflammation in lacrimal gland and reduce apoptosis of lacrimal gland cells.

Overview of Mandibular Condyle Fracture

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Su-Seong Park

2012-07-01

Full Text Available The mandibular condyle is a region that plays a key role in the opening and closing ofthe mouth, and because fracture causes functional and aesthetic problems such as facialasymmetry, it is very important to perform accurate reduction. Traditionally, there has beendisagreement on how to manage fracture of the mandibular condyle. This review exploresthe misunderstanding of mandibular condyle fracture treatment and modern-day treatmentstrategies.

Application of Crestal Anesthesia for Treatment of Class I Caries in Posterior Mandibular Teeth

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Koroush Taheri Talesh

2011-03-01

Full Text Available Background and aims. Current infiltration techniques for achieving anesthesia in dental procedures are not applicable in posterior mandibular region because of its dense cortical bone. The aim of this study was to evaluate the efficacy of a specific infiltration anesthesia in posterior mandibular teeth instead of inferior alveolar nerve block for restorative procedures. Materials and methods. Crestal anesthesia (CA was assessed both clinically and by computed tomography scan for its efficacy and side effects. A combination of an opaque material (Ultravist and 2% lidocaine was used to trace the anesthetic solution. The combination was primarily injected in the gingival tissue of rabbit and was followed-up regularly for two weeks to assess any possible injury. After confirming its safety, a combination of these materials was injected to volunteers to assess efficacy and diffusion route. A total of 154 patients (77 female, 77 male with matched bilateral posterior teeth in mandible were selected randomly and an IANB and CA were performed randomly and separately in different sessions for the contra lateral teeth. The onset of anesthesia, anesthesia duration, pain, blood pressure, pulse rate, and consumed volume of anesthetic solution was recorded for each technique. Data were analyzed using paired t-test. Results. There were no significant differences in clinical attachment loss, pocket depth, bone level, plaque index, and free gingival margin between the two flaps (p>0.05. Conclusion. CA could be considered as a reliable and safe primary injection in posterior mandibular teeth for restorative treatments.

Overview of Mandibular Condyle Fracture

OpenAIRE

Park, Su-Seong; Lee, Keun-Cheol; Kim, Seok-Kwun

2012-01-01

The mandibular condyle is a region that plays a key role in the opening and closing of the mouth, and because fracture causes functional and aesthetic problems such as facial asymmetry, it is very important to perform accurate reduction. Traditionally, there has been disagreement on how to manage fracture of the mandibular condyle. This review explores the misunderstanding of mandibular condyle fracture treatment and modern-day treatment strategies.

Overview of Mandibular Condyle Fracture

Directory of Open Access Journals (Sweden)

Su-Seong Park

2012-07-01

Full Text Available The mandibular condyle is a region that plays a key role in the opening and closing of the mouth, and because fracture causes functional and aesthetic problems such as facial asymmetry, it is very important to perform accurate reduction. Traditionally, there has been disagreement on how to manage fracture of the mandibular condyle. This review explores the misunderstanding of mandibular condyle fracture treatment and modern-day treatment strategies.

Relationship between fracture of mandibular condyle and absence of unerupted mandibular third molar-a retrospective study.

Science.gov (United States)

Rajan, Ritesh; Verma, Dinesh Kumar; Borle, R M; Yadav, Abhilasha

2016-06-01

The purpose of the present study was to find, if there exists, a co-relation between presence of unerupted mandibular third molar and fracture of mandibular condyle. A retrospective, multicenter study was done collecting the data of all mandibular condyle fractures treated from November 2006 till August 2015. Data was collected from the patient's records and radiographs for the following information: age, sex, etiology of fracture, presence and state of lower third molars, and associated fracture. The results were subjected to statistical analysis. Out of 180 patients of condylar fracture, unerupted third molars were present in 35 (19.44 %) cases compared to 145 (80.55 %) cases of condylar fracture where the unerupted third molars were not present. The difference was statistically significant (p fracture was seen in 4 (11.4 %) cases, bilateral condylar fracture associated with other mandibular fractures in 9 (25.7 %) cases, isolated unilateral condylar fracture in 0 (0.0 %) cases, and unilateral condylar fracture associated with other mandibular fractures in 17 (48.5 %) cases and condylar fracture associated with mid face fractures in 5 (14.2 %) cases. In the unerupted third molar absent group, isolated bilateral condylar fracture was seen in 5 (3.4 %) cases, bilateral condylar fracture associated with other mandibular fractures in 30 (20.6 %) cases, isolated unilateral condylar fracture in 24 (16.5 %) cases, unilateral condylar fracture associated with other mandibular fractures in 73 (50.34 %) cases, and condylar fracture associated with mid face fractures in 13(8.96 %) cases. The difference between the groups was statistically significant (p = 0.032). This study suggests that the fractures of mandibular condylar region have a significantly higher incidence in patients without an unerupted mandibular third molar.

Perfusion-induced changes in cardiac contractility depend on capillary perfusion.

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Dijkman, M A; Heslinga, J W; Sipkema, P; Westerhof, N

1998-02-01

The perfusion-induced increase in cardiac contractility (Gregg phenomenon) is especially found in heart preparations that lack adequate coronary autoregulation and thus protection of changes in capillary pressure. We determined in the isolated perfused papillary muscle of the rat whether cardiac muscle contractility is related to capillary perfusion. Oxygen availability of this muscle is independent of internal perfusion, and perfusion may be varied or even stopped without loss of function. Muscles contracted isometrically at 27 degrees C (n = 7). During the control state stepwise increases in perfusion pressure resulted in all muscles in a significant increase in active tension. Muscle diameter always increased with increased perfusion pressure, but muscle segment length was unaffected. Capillary perfusion was then obstructed by plastic microspheres (15 microns). Flow, at a perfusion pressure of 66.6 +/- 26.2 cmH2O, reduced from 17.6 +/- 5.4 microliters/min in the control state to 3.2 +/- 1.3 microliters/min after microspheres. Active tension developed by the muscle in the unperfused condition before microspheres and after microspheres did not differ significantly (-12.8 +/- 29.4% change). After microspheres similar perfusion pressure steps as in control never resulted in an increase in active tension. Even at the two highest perfusion pressures (89.1 +/- 28.4 and 106.5 +/- 31.7 cmH2O) that were applied a significant decrease in active tension was found. We conclude that the Gregg phenomenon is related to capillary perfusion.

Hepatic perfusion during hepatic artery infusion chemotherapy: Evaluation with perfusion CT and perfusion scintigraphy

International Nuclear Information System (INIS)

Miller, D.L.; Carrasquillo, J.A.; Lutz, R.J.; Chang, A.E.

1989-01-01

The standard method for the evaluation of hepatic perfusion during hepatic artery infusion (HAI) chemotherapy is planar hepatic artery perfusion scintigraphy (HAPS). Planar HAPS was performed with 2 mCi of [99mTc] macroaggregated albumin infused at 1 ml/min and compared with single photon emission CT (SPECT) HAPS and with a new study, CT performed during the slow injection of contrast material through the HAI catheter (HAI-CT). Thirteen patients underwent 16 HAI-CT studies, 14 planar HAPS studies, and 9 SPECT HAPS studies. In 13 of 14 studies (93%) HAI-CT and planar HAPS were in complete agreement as to the perfusion pattern of intrahepatic metastases and normal liver. In nine studies where all modalities were performed, the findings identified by HAI-CT and planar HAPS agreed in all cases, whereas the results of two SPECT scans disagreed with the other studies. With respect to perfusion of individual metastases, 14 of 14 HAI-CT studies, 12 of 13 planar HAPS studies, and 9 of 9 SPECT HAPS studies correctly demonstrated the perfusion status of individual lesions as indicated by the pattern of changes in tumor size determined on CT obtained before and after the perfusion studies. Hepatic artery infusion CT was superior for delineation of individual metastases, particularly small lesions, and for the evaluation of nonperfused portions of the liver. Planar HAPS detected extrahepatic perfusion in four patients, and this was not detected by HAI-CT. We conclude that HAI-CT and scintigraphy are complementary techniques. Hepatic artery infusion CT has advantages for the evaluation of intrahepatic perfusion, and planar HAPS is superior to HAI-CT for the detection of extrahepatic perfusion

Models of torsades de pointes: effects of FPL64176, DPI201106, dofetilide, and chromanol 293B in isolated rabbit and guinea pig hearts.

Science.gov (United States)

Cheng, Hsien C; Incardona, Josephine

2009-01-01

For studying the torsades de pointes (TdP) liability of a compound, most high and medium throughput methods use surrogate markers such as HERG inhibition and QT prolongation. In this study, we have tested whether isolated hearts may be modified to allow TdP to be the direct readout. Isolated spontaneously beating rabbit and guinea pig hearts were perfused according to the Langendorff method in hypokalemic (2.1 mM) solution. The in vitro lead II ECG equivalent and the incidence of TdP were monitored for 1 h. In addition, heart rate, QTc, Tp-Te, short-term variability (STV), time to arrhythmia, and time to TdP were also analyzed. FPL64176, a calcium channel activator; and DPI201106, a sodium channel inactivation inhibitor, produced TdP in isolated rabbit and guinea pig hearts in a concentration dependent manner; guinea pig hearts were 3- to 5-fold more sensitive than rabbit hearts. Both compounds also increased QTc and STV. In contrast, dofetilide, an IKr inhibitor, produced no (or a low incidence of) TdP in both species, in spite of prolongation of QTc intervals. Chromanol 293B, an IKs inhibitor, did not produce TdP in rabbit hearts but elicited TdP concentration dependently in guinea pig hearts even though the compound had no effect on QTc intervals. IKs inhibition appears to be more likely to produce TdP in isolated guinea pig hearts than IKr inhibition. Chromanol 293B did not produce TdP in rabbit hearts presumably due to a low level of IKs channels in the heart. TdP produced in this study was consistent with the notion that its production was a consequence of reduced repolarization reserve, thereby causing rhythmic abnormalities. This isolated, perfused, and spontaneously beating rabbit and guinea pig heart preparation in hypokalemic medium may be useful as a preclinical test model for studying proarrhythmic liability of compounds in new drug development.

Corticosteroid Reduces Blood Flow to Femoral Heads in Rabbits.

Science.gov (United States)

Hou, S.M.; Liu, T.K.; Kao, M.C.

1994-12-01

Avascular necrosis of the femoral head is one of the common problems in orthopedic practice in Taiwan. The subchondral bone loses its blood supply which weakens its biomechanical support. Steroid overuse is one of many possible etiologies in reducing blood flow to the femoral head. Laser Doppler velocimeter is a precise monitor of regional blood flow of bone which is expressed in perfusion units (PU). In the control group the rabbits were injected with normal saline and there were no statistical differences between blood flow to the right hip (39.26 +/- 5.64 PU) and left hip (38.58 +/- 4.35 PU). In group B a weekly injection of methylprednisolone into rabbits for 6 weeks demonstrated the reduction of blood flow of femoral head (24.74 +/- 3.13 PU) by the laser Doppler velocimeter. The flow decreased further (15.93 +/- 2.33 PU) by 12 weeks of steroid treatment. In group C after a weekly injection of steroid for 6 weeks the flow became 31.63 +/- 4.79 PU. The steroid was then discontinued for 3 weeks and the flow was 34.6 +/- 1.34 PU. In group D the blood flow was 25.89 +/- 4.01 PU after 6 weeks of steroid treatment and we stopped the steroid for 6 weeks, the blood flow became 29.86 +/- 2.59 PU. The merit of our experiment established a model of study in avascular necrosis of the femoral head in rabbits. Copyright 1994 S. Karger AG, Basel

Restoration of a Critical Mandibular Bone Defect Using Human Alveolar Bone-Derived Stem Cells and Porous Nano-HA/Collagen/PLA Scaffold

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Xing Wang

2016-01-01

Full Text Available Periodontal bone defects occur in a wide variety of clinical situations. Adult stem cell- and biomaterial-based bone tissue regeneration are a promising alternative to natural bone grafts. Recent evidence has demonstrated that two populations of adult bone marrow mesenchymal stromal cells (BMSCs can be distinguished based on their embryonic origins. These BMSCs are not interchangeable, as bones preferentially heal using cells that share the same embryonic origin. However, the feasibility of tissue engineering using human craniofacial BMSCs was unclear. The goal of this study was to explore human craniofacial BMSC-based therapy for the treatment of localized mandibular defects using a standardized, minimally invasive procedure. The BMSCs’ identity was confirmed. Scanning electron microscopy, a cell proliferation assay, and supernatant detection indicated that the nHAC/PLA provided a suitable environment for aBMSCs. Real-time PCR and electrochemiluminescence immunoassays demonstrated that osteogenic markers were upregulated by osteogenic preinduction. Moreover, in a rabbit critical-size mandibular bone defect model, total bone formation in the nHAC/PLA + aBMSCs group was significantly higher than in the nHAC/PLA group but significantly lower than in the nHAC/PLA + preinduced aBMSCs. These findings demonstrate that this engineered bone is a valid alternative for the correction of mandibular bone defects.

Restoration of a Critical Mandibular Bone Defect Using Human Alveolar Bone-Derived Stem Cells and Porous Nano-HA/Collagen/PLA Scaffold

Science.gov (United States)

Wang, Xing; Xing, Helin; Zhang, Guilan; Wu, Xia; Zou, Xuan; Feng, Lin; Wang, Dongsheng; Li, Meng; Zhao, Jing; Du, Jianwei; Lv, Yan; E, Lingling; Liu, Hongchen

2016-01-01

Periodontal bone defects occur in a wide variety of clinical situations. Adult stem cell- and biomaterial-based bone tissue regeneration are a promising alternative to natural bone grafts. Recent evidence has demonstrated that two populations of adult bone marrow mesenchymal stromal cells (BMSCs) can be distinguished based on their embryonic origins. These BMSCs are not interchangeable, as bones preferentially heal using cells that share the same embryonic origin. However, the feasibility of tissue engineering using human craniofacial BMSCs was unclear. The goal of this study was to explore human craniofacial BMSC-based therapy for the treatment of localized mandibular defects using a standardized, minimally invasive procedure. The BMSCs' identity was confirmed. Scanning electron microscopy, a cell proliferation assay, and supernatant detection indicated that the nHAC/PLA provided a suitable environment for aBMSCs. Real-time PCR and electrochemiluminescence immunoassays demonstrated that osteogenic markers were upregulated by osteogenic preinduction. Moreover, in a rabbit critical-size mandibular bone defect model, total bone formation in the nHAC/PLA + aBMSCs group was significantly higher than in the nHAC/PLA group but significantly lower than in the nHAC/PLA + preinduced aBMSCs. These findings demonstrate that this engineered bone is a valid alternative for the correction of mandibular bone defects. PMID:27118977

The role of simultaneous gap arthroplasty and distraction osteogenesis in the management of temporo-mandibular joint ankylosis with mandibular deformity in children.

Science.gov (United States)

Rao, Krishna; Kumar, Sudhir; Kumar, Vijay; Singh, Arun Kumar; Bhatnagar, Sudhir Kumar

2004-02-01

Temporo-mandibular joint ankylosis is a common cause of acquired deformity in children. Surgical correction of the ankylosis only leaves the patient with an uncorrected mandibular deformity. This study was to evaluate the use of distraction osteogenesis for simultaneous correction of the mandibular deformity. This study was done on six children with temporo-mandibular joint ankylosis and mandibular deformity. Uniaxial double pin distractors with Schanz pins were used in this study. The patients underwent simultaneous gap arthroplasty and mandibular osteotomy (retromolar) with distractor insertion. Distraction was started on the fifth post-operative day. The patients were put on dynamic temporo-mandibular joint exercises on the first post-operative day. All patients had a satisfactory mouth opening on follow-up. Satisfactory cosmetic correction of the mandibular deformity was also achieved in all these patients. Some degree of malocclusion resulted from treatment due to which the patients were placed on orthodontic treatment. Distraction osteogenesis can be used simultaneously with gap arthroplasty in patients with temporo-mandibular ankylosis, for the correction of the mandibular deformity.

Dorsal Branches of Abdominal Aorta in the Rabbit and the European Hare

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Flešárová S.

2016-06-01

Full Text Available The aim of this study was to describe the anatomical arrangement of the branches arising from the dorsal surface of the aorta abdominalis in the rabbit and the hare. The study was carried out on ten adult rabbits and ten adult European hares using the corrosion technique. After the euthanasia, the vascular network was perfused with saline. After polymerization of the casting medium, the maceration was carried out in a KOH solution. We found different variations in; the number of arteries, level of their origin and arrangement. The aa. lumbales of the same level arose by means of a common trunk or their origin was independent. The aa. lumbales VI or aa. lumbales VI et VII originated also from the a. sacralis mediana. By aa. lumbales we found an important interspecies difference in; number, diameter, ramification and density of dorsal branches, which are designated for the dorsal muscles of the body stem. All listed parameters of branches were higher in the hare. This anatomical arrangement of dorsal branches is adapted to the higher movement activity of the hare. According to our results, it can be concluded that the anatomical arrangement of the branches of the aorta abdominalis shows a higher number of variations in the domesticated rabbit in comparison with the hare.

Thin-plate spline analysis of mandibular growth.

Science.gov (United States)

Franchi, L; Baccetti, T; McNamara, J A

2001-04-01

The analysis of mandibular growth changes around the pubertal spurt in humans has several important implications for the diagnosis and orthopedic correction of skeletal disharmonies. The purpose of this study was to evaluate mandibular shape and size growth changes around the pubertal spurt in a longitudinal sample of subjects with normal occlusion by means of an appropriate morphometric technique (thin-plate spline analysis). Ten mandibular landmarks were identified on lateral cephalograms of 29 subjects at 6 different developmental phases. The 6 phases corresponded to 6 different maturational stages in cervical vertebrae during accelerative and decelerative phases of the pubertal growth curve of the mandible. Differences in shape between average mandibular configurations at the 6 developmental stages were visualized by means of thin-plate spline analysis and subjected to permutation test. Centroid size was used as the measure of the geometric size of each mandibular specimen. Differences in size at the 6 developmental phases were tested statistically. The results of graphical analysis indicated a statistically significant change in mandibular shape only for the growth interval from stage 3 to stage 4 in cervical vertebral maturation. Significant increases in centroid size were found at all developmental phases, with evidence of a prepubertal minimum and of a pubertal maximum. The existence of a pubertal peak in human mandibular growth, therefore, is confirmed by thin-plate spline analysis. Significant morphological changes in the mandible during the growth interval from stage 3 to stage 4 in cervical vertebral maturation may be described as an upward-forward direction of condylar growth determining an overall "shrinkage" of the mandibular configuration along the measurement of total mandibular length. This biological mechanism is particularly efficient in compensating for major increments in mandibular size at the adolescent spurt.

Laser asga effect on the normal anatomy of the temporo mandibular joint (TMJ) on the rabbit

OpenAIRE

Matamala V, Fernando; Cornejo U, Ricardo; Vasconcellos C, Adriana; Silva M, Héctor

2009-01-01

El láser blando o infrarrojo es utilizado en clínica veterinaria por sus efectos analgésicos, antiinflamatorios, bioestimulantes y curativos, a fin de tratar lesiones y mejorar el proceso de cicatrización. El presente estudio tiene como propósito evaluar el efecto del láser infrarrojo de AsGa (10miliwatt,780 nanómetros, 2joule/cm²) sobre la articulación témporo mandibular (ATM) de conejo, para determinar las alteraciones que produce este tipo de irradiación sobre los tejidos normales. Se util...

Quantification of in-stent restenosis parameters in rabbits by micro-CT

International Nuclear Information System (INIS)

Langheinrich, A.C.; Zoerb, C.; Jajima, J.; Lommel, D.; Rau, W.S.; Walker, G.; Mueller, K.M.; Bohle, R.M.

2005-01-01

Purpose: The well-defined model of angioplasty and stent implantation in the rabbit aorta is useful in experimental studies of restenosis. This study was performed to evaluate the feasibility of Micro-CT for quantification of in-stent restenosis in a rabbit aortic in-stent restenosis model. Material and Methods: To induce in-stent restenosis seven female New Zealand rabbits underwent balloon dilation and denudation prior to stenting the abdominal aorta. After six weeks on atherogenic diet, animals were killed and the aorta was perfused with contrast agent. Micro-CT morphometric analysis of balloon and stent injured arteries obtained by 700 transverse sections (voxel size 10 μm) was compared to conventional histological analysis. Results: Intimal hyperplasia was present in stented and balloon injured arteries with a moderate intimal area assessed by Micro-CT and conventional histology (3.91±0.5 mm 2 vs. 4.18±0.42; r=0.9). High significant correlations between Micro-CT image analysis and conventional histomorphometry were obtained for lesion size, size of media, size of lumen and stent area (r=0.84 to 0.96). Conclusion: Micro-CT is feasible for quantitative information about restenosis following balloon angioplasty and stent implantation and has the potential to become a standard technique in many laboratories which will augment serial histology as the reference method for ex-vivo studies of restenosis. (orig.)

MORPHOMETRIC ANALYSIS OF MANDIBULAR FORAMEN AND INCIDENCE OF ACCESSORY MANDIBULAR FORAMINA IN ADULT HUMAN MANDIBLES OF AN INDIAN POPULATION. Análisis morfométrico del foramen mandibular e incidencia de la foramina mandibular accesoria en mandíbulas adult

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Prajna Paramita Samanta

2016-03-01

Full Text Available El foramen mandibular es un importante hito anatómico. Para procedimientos como el bloqueo alveolar inferior del nervio, el tratamiento con implantes y osteotomías mandibulares, un profundo conocimiento de la ubicación del foramen mandibular (MF y el foramen mandibular accesorio (AMF es un requisito previo. Hay pocas referencias en la literatura con respecto a la localización anatómica exacta del foramen mandibular. Por lo tanto, el presente estudio tuvo como objetivo identificar la ubicación exacta de la MF y la incidencia de la AMF alrededor MF en una población india. Sesenta (60 mandíbulas humanas adultas fueron estudiadas para determinar la distancia del LV de la los anteriores, bordes posteriores de la rama mandibular, maxilar inferior categoría y el ángulo de la mandíbula. AMF todo el MF también fueron estudiados por su presencia y números. La distancia media de MF del borde anterior de rama mandibular fue 15,72 ±2,92 mm(lado derecho, 16,23 ±2,88 mm(lado izquierdo, de borde posterior fue 13,29 ±1,74 mm(lado derecho y 12,73 ±2,04 mm(a la izquierda lado. La MF se encuentra 22,70 ±3 mm(lado derecho y 22, 27 ± 2,62 mm(lado izquierdo de la muesca mandibular. La distancia de MF de ángulo de la mandíbula fue 21,54 ±2,92 mm(lado derecho y 21,13 ±3.43 mm(lado izquierdo. AMF estuvieron presentes en el 16, 66% de las mandíbulas. En 10% de las mandíbulas una sola AMF estaba presente y en el 6,66% hubo dos agujeros presentes. La ubicación del MF y AMF es importante para evitar compli-caciones como hemorragia y parestesia durante los procedimientos quirúrgicos orales y también para los radioterapeutas en la planificación de la radioterapia.  The mandibular foramen is an important anatomical land mark. For procedures like inferior alveolar nerve block, implant treatment and mandibular osteotomies, a thorough knowledge of the location of the mandibular foramen (MF and accessory mandibular foramina (AMFs is a prerequisite

Measuring mandibular ridge reduction

International Nuclear Information System (INIS)

Steen, W.H.A.

1984-01-01

This thesis investigates the mandibular reduction in height of complete denture wearers and overdenture wearers. To follow this reduction in the anterior region as well as in the lateral sections of the mandible, an accurate and reproducible measuring method is a prerequisite. A radiologic technique offers the best chance. A survey is given of the literature concerning the resorption process after the extraction of teeth. An oblique cephalometric radiographic technique is introduced as a promising method to measure mandibular ridge reduction. The reproducibility and the accuracy of the technique are determined. The reproducibility in the positioning of the mandible is improved by the introduction of a mandibular support which permits a precise repositioning of the edentulous jaw, even after long periods of investigation. (Auth.)

Mandibular canal branches supplying the mandibular third molar observed on cone beam computed tomographic images: Reports of four cases

Energy Technology Data Exchange (ETDEWEB)

Lee, Jae Seo; Yoon, Suk Ja; Kang, Byung Cheol [Department of Oral and Maxillofacial Radiology, School of Dentistry, Dental Science Research Institute, Chonnam National University, Gwangju (Korea, Republic of)

2009-12-15

Bifid mandibular canal can be an anatomic variation. This condition can lead to complication when performing mandibular anesthesia or during extraction of lower third molar, placement of implants and surgery in the mandible. Four patients underwent preoperative imaging for extraction of third molars using CBCT (CB Mercuray, Hitachi, Japan). The axial images were processed with CBworks program 2.1 (CyberMed Inc., Seoul, Korea). The branches for supplying the lower third molar were identified mainly on cross-sectional and panoramic images of CBCT. Since the location and configuration of mandibular canal variations are important in any mandibular surgical procedures, we report 4 cases of bifid mandibular canal with panoramic and the CBCT images.

[Orthodontic treatment of Class III patients with mandibular asymmetry].

Science.gov (United States)

Duan, Yin-Zhong; Huo, Na; Chen, Lei; Chen, Xue-Peng; Lin, Yang

2008-12-01

To investigate the treatment outcome of Class III patients with dental, functional and mild skeletal mandibular asymmetry. Thirty-five patients (14 males and 21 females) with dental, functional and mild skeletal mandibular asymmetry were selected. The age range of the patients was 7 - 22 years with a mean age of 16.5 years. Dental mandibular asymmetry was treated with expansion of maxillary arch to help the mandible returning to normal position. Functional mandibular asymmetry was treated with activator or asymmetrical protraction and Class III elastics. Mild skeletal mandibular asymmetry was treated with camouflage treatment. Good occlusal relationships were achieved and facial esthetics was greatly improved after orthodontic treatment in patients with dental and functional mandibular asymmetry. However, patients with skeletal mandibular asymmetry should be treated with both extraction and genioplasty. Orthodontic treatment was suitable for patients with dental and functional mandibular asymmetry, while combined orthodontics and surgery could get good results in patients with skeletal mandibular asymmetry.

Gene expression of osteogenic factors following gene therapy in mandibular lengthening.

Science.gov (United States)

Wu, Guoping; Zhou, Bin; Hu, Chunbing; Li, Shaolan

2015-03-01

This study investigated the effect of gene therapy on the expression of osteogenic mediators in mandibular distraction osteogenesis rabbits. Bilateral mandibular osteotomies were performed in 45 New-Zealand rabbits. After a latency of 3 days, the mandibles were elongated using distractors with a rate of 0.8 mm/d for 7 days. After the completion of distraction, the rabbits were randomly divided into 5 groups: 2 μg (0.1 μg/μL) of recombinant plasmid pIRES-hVEGF165-hBMP-2, recombinant plasmid pIRES-hBMP2, recombinant plasmid pIRES-hVEGF165, pIRES, and the same volume of normal saline were injected into the distraction gap of groups A, B, C, D, and E, respectively, followed by electroporation. Three animals were killed at the 7th, 14th, and 28th day after gene transfected in different groups, respectively. The lengthened mandibles were harvested and processed for immunohistochemical examinations; the mean optic densities (MODs) and integral optical density of bone morphogenetic protein (BMP-2) and transforming growth factor β1 (TGF-β1)-positive cells were measured by CMIAS-2001A computerized image analyzer. The data were analyzed with SPSS (SPSS Inc, Chicago, IL). Bone morphogenetic protein 2 and TGF-β1 staining was mainly located in inflammatory cells, monocytes, fibroblasts, osteoblasts, osteocytes, and chondrocytes in the distraction zones. Their strongest expression reached to the peak at the seventh day and decreased at the 14th day of consolidation stage; at the 28th day, they expressed weakly. Image analysis results show that, at the seventh day, the expression of BMP-2 in group B (0.26 ± 0.03, 0.36 ± 0.02) was the strongest; there was significant difference among them (P < 0.01), whereas the expression of TGF-β1 in group C (0.38 ± 0.06, 1.05 ± 0.19) is strongest followed by group A (0.34 ± 0.05, 0.95 ± 0.16) and B (0.33 ± 0.07, 0.90 ± 0.19). At every time point, the level of expression of BMP-2 and TGF-β1 in gene therapy groups (groups A, B, and

21 CFR 872.3960 - Mandibular condyle prosthesis.

Science.gov (United States)

2010-04-01

... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3960 Mandibular condyle prosthesis. (a) Identification. A mandibular condyle prosthesis is a device that is intended to be implanted in the human jaw to... requirement for premarket approval for any mandibular condyle prosthesis intended to be implanted in the human...

Isoflurane administration before ischemia and during reperfusion attenuates ischemia/reperfusion-induced injury of isolated rabbit lungs.

Science.gov (United States)

Liu, R; Ishibe, Y; Ueda, M; Hang, Y

1999-09-01

To investigate the effects of isoflurane on ischemia/ reperfusion (IR)-induced lung injury, we administered isoflurane before ischemia or during reperfusion. Isolated rabbit lungs were divided into the following groups: control (n = 6), perfused and ventilated for 120 min without ischemia; ISO-control (n = 6), 1 minimum alveolar anesthetic concentration (MAC) isoflurane was administered for 30 min before 120 min continuous perfusion; IR (n = 6), ischemia for 60 min, followed by 60 min reperfusion; IR-ISO1 and IR-ISO2, ischemia followed by reperfusion and 1 MAC (n = 6) or 2 MAC (n = 6) isoflurane for 60 min; ISO-IR (n = 6), 1 MAC isoflurane was administered for 30 min before ischemia, followed by IR. During these maneuvers, we measured total pulmonary vascular resistance (Rt), coefficient of filtration (Kfc), and lung wet to dry ratio (W/D). The results indicated that administration of isoflurane during reperfusion inhibited an IR-induced increase in Kfc and W/D ratio. Furthermore, isoflurane at 2 MAC, but not 1 MAC, significantly inhibited an IR-induced increase in Rt. The administration of isoflurane before ischemia significantly attenuated the increase in IR-induced Kfc, W/D, and Rt. Our results suggest that the administration of isoflurane before ischemia and during reperfusion protects against ischemia-reperfusion-induced injury in isolated rabbit lungs.

Radiological Assessment of Bioengineered Bone in a Muscle Flap for the Reconstruction of Critical-Size Mandibular Defect

Science.gov (United States)

Al-Fotawei, Randa; Ayoub, Ashraf F.; Heath, Neil; Naudi, Kurt B.; Tanner, K. Elizabeth; Dalby, Matthew J.; McMahon, Jeremy

2014-01-01

This study presents a comprehensive radiographic evaluation of bone regeneration within a pedicled muscle flap for the reconstruction of critical size mandibular defect. The surgical defect (20 mm×15 mm) was created in the mandible of ten experimental rabbits. The masseter muscle was adapted to fill the surgical defect, a combination of calcium sulphate/hydroxyapatite cement (CERAMENT™ |SPINE SUPPORT), BMP-7 and rabbit mesenchymal stromal cells (rMSCs) was injected inside the muscle tissue. Radiographic assessment was carried out on the day of surgery and at 4, 8, and 12 weeks postoperatively. At 12 weeks, the animals were sacrificed and cone beam computerized tomography (CBCT) scanning and micro-computed tomography (µ-CT) were carried out. Clinically, a clear layer of bone tissue was identified closely adherent to the border of the surgical defect. Sporadic radio-opaque areas within the surgical defect were detected radiographically. In comparison with the opposite non operated control side, the estimated quantitative scoring of the radio-opacity was 46.6% ±15, the mean volume of the radio-opaque areas was 63.4% ±20. Areas of a bone density higher than that of the mandibular bone (+35% ±25%) were detected at the borders of the surgical defect. The micro-CT analysis revealed thinner trabeculae of the regenerated bone with a more condensed trabecular pattern than the surrounding native bone. These findings suggest a rapid deposition rate of the mineralised tissue and an active remodelling process of the newly regenerated bone within the muscle flap. The novel surgical model of this study has potential clinical application; the assessment of bone regeneration using the presented radiolographic protocol is descriptive and comprehensive. The findings of this research confirm the remarkable potential of local muscle flaps as local bioreactors to induce bone formation for reconstruction of maxillofacial bony defects. PMID:25226170

Radiological assessment of bioengineered bone in a muscle flap for the reconstruction of critical-size mandibular defect.

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Randa Al-Fotawei

Full Text Available This study presents a comprehensive radiographic evaluation of bone regeneration within a pedicled muscle flap for the reconstruction of critical size mandibular defect. The surgical defect (20 mm × 15 mm was created in the mandible of ten experimental rabbits. The masseter muscle was adapted to fill the surgical defect, a combination of calcium sulphate/hydroxyapatite cement (CERAMENT™ |SPINE SUPPORT, BMP-7 and rabbit mesenchymal stromal cells (rMSCs was injected inside the muscle tissue. Radiographic assessment was carried out on the day of surgery and at 4, 8, and 12 weeks postoperatively. At 12 weeks, the animals were sacrificed and cone beam computerized tomography (CBCT scanning and micro-computed tomography (µ-CT were carried out. Clinically, a clear layer of bone tissue was identified closely adherent to the border of the surgical defect. Sporadic radio-opaque areas within the surgical defect were detected radiographically. In comparison with the opposite non operated control side, the estimated quantitative scoring of the radio-opacity was 46.6% ± 15, the mean volume of the radio-opaque areas was 63.4% ± 20. Areas of a bone density higher than that of the mandibular bone (+35% ± 25% were detected at the borders of the surgical defect. The micro-CT analysis revealed thinner trabeculae of the regenerated bone with a more condensed trabecular pattern than the surrounding native bone. These findings suggest a rapid deposition rate of the mineralised tissue and an active remodelling process of the newly regenerated bone within the muscle flap. The novel surgical model of this study has potential clinical application; the assessment of bone regeneration using the presented radiolographic protocol is descriptive and comprehensive. The findings of this research confirm the remarkable potential of local muscle flaps as local bioreactors to induce bone formation for reconstruction of maxillofacial bony defects.

Mandibular ameloblastomas

International Nuclear Information System (INIS)

Masip, M.J.; Arana, E.; Beltran, J.; Garcia, J.L.; Cifrian, C.; Aparisi, F.

1995-01-01

We present a retrospective review of 39 cases of mandibular ameloblastoma that were assessed in terms of patient age and sex, duration and clinical signs at the time of diagnosis. The associated plain radiology, CT and MR signs are also reviewed. It usually presented as a slowly growing, painless mass. According to radiological findings, most of the ameloblastomas studied were extensive, involving the mandibular branch, angle and molar area; the lesions were expanding, unilocular or multilocular, with erosion of the dental apex. CT disclosed cystic areas of low attenuation. The images of the three patients studied by MR presented low signal intensity in T1-weighed sequences and hyperintense signal in t2-weighted sequences. 9 refs

Quantitative lung perfusion evaluation using Fourier decomposition perfusion MRI.

Science.gov (United States)

Kjørstad, Åsmund; Corteville, Dominique M R; Fischer, Andre; Henzler, Thomas; Schmid-Bindert, Gerald; Zöllner, Frank G; Schad, Lothar R

2014-08-01

To quantitatively evaluate lung perfusion using Fourier decomposition perfusion MRI. The Fourier decomposition (FD) method is a noninvasive method for assessing ventilation- and perfusion-related information in the lungs, where the perfusion maps in particular have shown promise for clinical use. However, the perfusion maps are nonquantitative and dimensionless, making follow-ups and direct comparisons between patients difficult. We present an approach to obtain physically meaningful and quantifiable perfusion maps using the FD method. The standard FD perfusion images are quantified by comparing the partially blood-filled pixels in the lung parenchyma with the fully blood-filled pixels in the aorta. The percentage of blood in a pixel is then combined with the temporal information, yielding quantitative blood flow values. The values of 10 healthy volunteers are compared with SEEPAGE measurements which have shown high consistency with dynamic contrast enhanced-MRI. All pulmonary blood flow (PBF) values are within the expected range. The two methods are in good agreement (mean difference = 0.2 mL/min/100 mL, mean absolute difference = 11 mL/min/100 mL, mean PBF-FD = 150 mL/min/100 mL, mean PBF-SEEPAGE = 151 mL/min/100 mL). The Bland-Altman plot shows a good spread of values, indicating no systematic bias between the methods. Quantitative lung perfusion can be obtained using the Fourier Decomposition method combined with a small amount of postprocessing. Copyright © 2013 Wiley Periodicals, Inc.

Trichostatin A (TSA) improves the development of rabbit-rabbit intraspecies cloned embryos, but not rabbit-human interspecies cloned embryos.

Science.gov (United States)

Shi, Li-Hong; Miao, Yi-Liang; Ouyang, Ying-Chun; Huang, Jun-Cheng; Lei, Zi-Li; Yang, Ji-Wen; Han, Zhi-Ming; Song, Xiang-Fen; Sun, Qing-Yuan; Chen, Da-Yuan

2008-03-01

The interspecies somatic cell nuclear transfer (iSCNT) technique for therapeutic cloning gives great promise for treatment of many human diseases. However, the incomplete nuclear reprogramming and the low blastocyst rate of iSCNT are still big problems. Herein, we observed the effect of TSA on the development of rabbit-rabbit intraspecies and rabbit-human interspecies cloned embryos. After treatment with TSA for 6 hr during activation, we found that the blastocyst rate of rabbit-rabbit cloned embryos was more than two times higher than that of untreated embryos; however, the blastocyst rate of TSA-treated rabbit-human interspecies cloned embryos decreased. We also found evident time-dependent histone deacetylation-reacetylation changes in rabbit-rabbit cloned embryos, but not in rabbit-human cloned embryos from fusion to 6 hr after activation. Our results suggest that TSA-treatment does not improve blastocyst development of rabbit-human iSCNT embryos and that abnormal histone deacetylation-reacetylation changes in iSCNT embryos may account for their poor blastocyst development. (c) 2008 Wiley-Liss, Inc.

Sex differences and the development of the rabbit brain: effects of vinclozolin.

Science.gov (United States)

Bisenius, Erin S; Veeramachaneni, D N Rao; Sammonds, Ginger E; Tobet, Stuart

2006-09-01

The preoptic/anterior hypothalamic area (POA/AH) is one of the most sexually dimorphic areas of the vertebrate brain and plays a pivotal role in regulating male sexual behavior. Vinclozolin is a fungicide thought to be an environmental antiandrogen, which disrupts masculine sexual behavior when administered to rabbits during development. In this study, we examined several characteristics of the rabbit POA/AH for sexual dimorphism and endocrine disruption by vinclozolin. Pregnant rabbits were dosed orally with vinclozolin (10 mg/kg body weight) or carrot paste vehicle once daily for 6 wk beginning at midgestation and continuing through nursing until Postpartum Week 4. At 6 wk, offspring were perfused with 4% paraformaldehyde and brains processed for immunocytochemical localization of tyrosine hydroxylase, calbindin, gonadotropin-releasing hormone (GnRH), or Nissl stain. There were significant sex differences in the distribution of calbindin in the POA/AH and the size of cells in the dorsal POA/AH (values greater in females than in males), but not in the number or distribution of tyrosine hydroxylase or GnRH neurons. In both sexes, exposure to vinclozolin significantly increased calbindin expression in the ventral POA/AH and significantly decreased number of GnRH neurons selectively in the region of the organum vasculosum of the lamina terminalis (OVLT) but not more caudally in the POA/AH. This is the first documentation of a sexually dimorphic region in the rabbit brain, and further supports the use of this species as a model for studying the influence of vinclozolin on reproductive development with potential application to human systems.

Renal perfusion scintiscan

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... Radionuclide renal perfusion scan; Perfusion scintiscan - renal; Scintiscan - renal perfusion Images Kidney anatomy Kidney - blood and urine flow Intravenous pyelogram References Rottenberg G, Andi AC. Renal ...

Hepatitis E Virus in Farmed Rabbits, Wild Rabbits and Petting Farm Rabbits in the Netherlands

NARCIS (Netherlands)

Burt, S.A.; Veltman, Jorg; Hakze-van der Honing, Renate; Schmitt, Heike; van der Poel, Wim H.M.

2016-01-01

Rabbits have been suggested as a zoonotic source of Hepatitis E virus. Phylogenetic analysis of HEV isolates from farmed, wild and pet rabbits in the Netherlands (23, 0, and 60 % respectively) showed them to be grouped amongst published rabbit HEV sequences and distinct from most human isolates.

Sodium addition and/or oxygen saturation of iohexol during normal and reduced perfusion pressure

International Nuclear Information System (INIS)

Baath, L.

1990-01-01

The influence on contractile force (CF) and the propensity for ventricular fibrillation (VF) from infusing the non-ionic contrast medium iohexol during normal (75 cm H 2 O) and reduced perfusion pressure (35 cm H 2 O) were investigated in the isolated rabbit heart. Both during normal and reduced perfusion pressure iohexol (150 mg I/ml) with oxygen saturation caused a smaller reduction of CF than iohexol without oxygen. During reduced pressure iohexol with sodium addition (28 mM NaCl) caused less depression of CF than iohexol without sodium. The combination of sodium addition and oxygen saturation had the least influence on CF. Iohexol (350 mg I/ml) without sodium had a similar fibrillatory propensity during both normal and reduced pressure. Enriching iohexol with 28 mM NaCl decreased the risk of VF. The decrease was similar during both normal and reduced pressure. The risk of VF from oxygen saturation of iohexol (350 mg I/ml, without sodium) was similar during both normal and reduced pressure. It is concluded that a small addition of sodium and/or oxygen saturation of a non-ionic monomeric contrast medium have beneficial effects on the heart both during normal perfusion pressure and during ischemia. (orig.)

Hepatitis E Virus in Farmed Rabbits, Wild Rabbits and Petting Farm Rabbits in the Netherlands

NARCIS (Netherlands)

Burt, Sara A.; Veltman, Jorg; Hakze-van der Honing, Renate; Schmitt, Heike; Poel, van der Wim H.M.

2016-01-01

Rabbits have been suggested as a zoonotic source of Hepatitis E virus. Phylogenetic analysis of HEV isolates from farmed, wild and pet rabbits in the Netherlands (23, 0, and 60 % respectively) showed them to be grouped amongst published rabbit HEV sequences and distinct from most human isolates.

Rotational Distraction for the Treatment of Severe Mandibular Retrognathia.

Science.gov (United States)

Ito, Osamu; Mitsugi, Masaharu; Alcalde, Rafael E; Yano, Tomoyuki; Uemura, Noriko; Okazaki, Mutsumi

2015-07-01

The main problem with intraoral distraction of the mandible is the inability to achieve the three-dimensional mandibular correction as planned preoperatively. We developed a technique that allows spontaneous changes in the direction of mandibular elongation using an intraoral distractor. After mandibular osteotomy, the distractor is fixed to the distal segment of the mandible using a single bicortical screw, allowing anterior-posterior, vertical and limited lateromedial changes in the vector of distraction. Mandibular lengthening is performed while keeping the maxilla and mandible in class I occlusion with intermaxillary fixation. As the distraction device is activated allowing mandibular elongation, the proximal segment, guided by the surrounding soft tissues, moves and rotates posterosuperiorly. Mandibular lengthening is continued until the condylar head reaches an adequate position in the mandibular fossa as confirmed clinically and radiographically. Thirty-three patients with mandibular retrognathia received this treatment and good results were obtained.

Anquilosis mandibular: una frecuente secuela por Noma Mandibular ankylosis: a Noma frequent sequel

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R. Fernández García-Guilarte

2009-12-01

Full Text Available Conocemos poco sobre el Noma o Enfermedad Cancrum Oris. Esta entidad afecta a niños con malnutrición crónica, poca higiene oral, poco desarrollo sanitario y enfermedades concurrentes debilitantes. Existe un consenso general sobre que el Noma empieza como una gingivitis; en su fase aguda, puede haber respuesta al tratamiento antibiótico, no obstante, las secuelas tras su curación incluyen daños estéticos y funcionales variables, que pueden requerir cirugía reconstructiva. Presentamos 3 casos de anquilosis mandibular que en el examen preoperatorio presentaron dimorfismo mandibular, fusión de hueso maxilar y mandibular y anquilosis de la articulación témporomandibular. La ortopantografía y la Tomografía Axial Computerizada (TAC fueron muy útiles en la planificación de la cirugía. El tratamiento quirúrgico consistió en todos los casos en la resección del hueso anquilótico y la reconstrucción con injerto condrocostal en uno de los casos. En el postoperatorio se siguió fisioterapia intensiva. Clínicamente todos los pacientes mostraron una gran mejoría en la masticación, la alimentación y el habla, obviamente debido a una buena oclusión. El problema más común fue la baja colaboración en la rehabilitación mandibular por parte de los pacientes.Little is known about Noma or Cancrum Oris Disease. This entity affects to children with chronic malnutrition, poor oral hygiene, poor environmental sanitation and debilitating concurrent illness. There is general consensus that noma starts as gingivitis. The acute stage responds readily to antibiotic treatment. The sequelae after healing include variable functional and aesthetic impairments, which require reconstructive surgery. We report 3 cases of mandibular ankylosis. Preoperative examination revealed mandibular dismorphism, fusion of maxilla and mandible and ankylosis of the temporomandibular joint. Orthopantography and Computed Thomography scan (TCS were very useful in planning

Possibility of estimating three-dimensional mandibular morphology by cephalogram analysis

International Nuclear Information System (INIS)

Kim, S.; Motegi, Etsuko; Kikuchi, Yu; Yamaguchi, Hideharu; Takaki, Takashi; Shibahara, Takahiko

2007-01-01

The purpose of this study was to investigate the possibility of a surmise of three-dimensional mandibular morphology by two-dimensional cephalogram analysis. The materials were three-dimensional CT and cephalogram of 20 female mandibular prognathism patients (average age: 25.20±7.49) before there orthognathic surgery. Mandibular bone volume and sponge bone width were calculated from three-dimensional images constructed from CT images using imaging software (Real Intage, KGT inc.). There was a positive correlation (r=0.72) between mandibular volume value and mandibular ramus width. There was a positive correlation between sponge bone width at the site of the mandibular cuspid and mandibular ramus width and SNB angle (r=0.80), and between sponge bone width at the site of the mandibular molar and symphysis height and mandibular ramus width (r=0.81). It was thought that these results will be useful for a surmise of three-dimensional mandibular morphology by cephalogram analysis. (author)

Pharyngeal airway changes following mandibular setback surgery

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Babu Ramesh

2005-01-01

Full Text Available Treatment of dentofacial deformities with jaw osteotomies has an effect on airway anatomy and therefore mandibular setback surgery has the potential to diminish airway size. The purpose of this study was to evaluate the effect of mandibular setback surgery on airway size. 8 consecutive patients were examined prospectively. All patients underwent mandibular setback surgery. Cephalometric analysis was performed preoperatively and 3 months post operatively with particular attention to pharyngeal airway changes. Pharyngeal airway size decreased considerably in all, patients thus predisposing to development of obstructive sleep apnea. Therefore, large anteroposterior discrepancies should be corrected by combined maxillary and mandibular osteotomies.

Biomechanical considerations in mandibular incisor extraction cases.

Science.gov (United States)

Rachala, Madhukar Reddy; Aileni, Kaladhar Reddy; Dasari, Arun Kumar; Sinojiya, Jay

2015-01-01

Mandibular incisor extraction can be regarded as a valuable treatment option in certain malocclusions to obtain excellence in orthodontic results in terms of function, aesthetics and stability. This treatment alternative is indicated in clinical situations like mild to moderate class III malocclusion, mild anterior mandibular tooth size excess, periodontally compromised teeth, ectopic eruption of mandibular incisor and minimal openbite tendencies. Unlike in premolar extraction cases, space closure in mandibular incisor extraction cases is unique in which the extraction space will be in the middle of the arch. The end result of space closure in these cases should be well aligned, upright, anterior teeth with parallel roots and the goal can be achieved with the bodily tooth movement through proper application of biomechanics. The purpose of this article is to explain the biomechanics of space closure in mandibular incisor extraction cases.

Gene expression of fibrinolytic factors urokinase plasminogen activator and plasminogen activator inhibitor-1 in rabbit temporo-mandibular joint cartilage with disc displacement.

Science.gov (United States)

Zhan, Jing; Gu, Zhi-yuan; Wu, Li-qun; Zhang, Yin-kai; Hu, Ji-an

2005-06-20

The urokinase plasminogen activator system is believed to play an important role in degradation of the extracellular matrix associated with cartilage and bone destruction; however its precise roles in temporomandibular disorders have not yet been clarified. The aims of this study were to investigate the gene expression of fibrinolytic factors urokinase plasminogen activator (uPA) and plasminogen activator inhibitor-1 (PAI-1) in the articular cartilage of rabbit temporomandibular joint (TMJ) with disc displacement (DD) and to probe the relationship between fibrinolytic activity and cartilage remodeling. Disc displacement of right joints was performed in 36 of 78 rabbits under investigation. The animals were sacrificed at 4 days and 1, 2, 4, 8 and 12 weeks after surgery, respectively. The right joints of these animals were harvested and processed for the examination of mRNA expression of uPA and PAI-1 in articular cartilage using in situ hybridization techniques. The expression of uPA and PAI-1 was co-expressed weakly in the chondrocytes from transitive zone to hypertrophic zone and mineralized zone, while no hybridizing signals were shown in proliferative zone and superficial zone in control rabbits. The most striking was the up-regulation of uPA and PAI-1 mRNA in 4-day rabbits postoperatively at the onset of cartilage degeneration. The strongest hybridizing signals for uPA and PAI-1 were seen in 2-week rabbits postoperatively. After 2 weeks, the expression of uPA and PAI-1 began to decrease and reached nearly normal level at 12 weeks. The expression of the uPA/PAI-1 system coincides with the pathological changes in condylar cartilage after DD. The uPA/PAI-1 system may be one of the essential mediators in articular cartilage remodeling.

Anterior mandibular apical base augmentation in the surgical orthodontic treatment of mandibular retrusion.

Science.gov (United States)

Brusati, R; Giannì, A B

2005-12-01

The authors describe a surgical technique alternative to traditional pre-surgical orthodontics in order to increase the apical base in mandibular retrusion (class II, division I). This subapical osteotomy, optimizing inferior incisal axis without dental extractions and a long orthodontic treatment, associated to genioplasty permits to obtain an ideal labio-dento-mental morphology. This procedure avoids in some cases the need of a mandibular advancement and, if necessary, it reduces his entity with obvious advantages.

Influence of 60Co irradiation on the mandible of adult rabbit

International Nuclear Information System (INIS)

Umezaki, Yukio

1977-01-01

This study was performed in order to observe the effect of 60 Co γ-ray irradiation (5000, 8000 and 10000R) on rabbits' mandible, for as long as possible, approximately 18 months. Radiographical and histopathological studies were done after irradiation. The upper anterior teeth of all experimental animals showed elongation, lateral flection and diasthema. The lower anterior teeth showed shortening or disappearance of the crowns and resorption of the root apex in all. These teeth were lost eventually. Molar teeth disclosed shortening of crowns and irregular and partial loss on the surface of the dentine. Pulp chambers were extremely narrowed. These changes were most conspicuous in the 10,000R irradiation group. Mandibular fractures occurred in 13 cases, which include 3 cases with 5,000R, 4 cases with 8,000R and 6 cases with 10,000R. The alveolar bones were resorped, and were replaced with mandibular bone trabeculae. Various types of ankylosis of root surface and mandibulars were seen. These changes were more frequently noted in the molar regions that the anterior regions and in the groups with higher doses and longer days after irradiation. Bone trabeculae and cortex of the mandibles were resorped in the 3 irradiation groups in the early stage, but regeneration and thickening of the bones occured later. The usual case was that the anterior bone marrow became more gelatinous and the molar marrow became more fibrous. Hyperemia and abscess formation were recognized in some cases. Although in the molar regions these pathological changes were conspicuous in proportion to the amount of dose, in the anterior regions, the same changes were more conspicuous in the 5,000R irradiation group than in the 8,000R group. (J.P.N.)

A patient with mandibular deviation and 3 mandibular incisors treated with asymmetrically bent improved superelastic nickel-titanium alloy wires.

Science.gov (United States)

Ikeda, Yuhei; Kokai, Satoshi; Ono, Takashi

2018-01-01

Skeletal and dental discrepancies cause asymmetric malocclusions in orthodontic patients. It is difficult to achieve adequate functional occlusion and guidance in patients with congenital absence of a mandibular incisor due to the tooth-size discrepancy. Here, we describe the orthodontic treatment of a 22-year-old woman with an asymmetric Angle Class II malocclusion, mandibular deviation to the left, and 3 mandibular incisors. The anterior teeth and maxillary canines were crowded. We used an improved superelastic nickel-titanium alloy wire (Tomy International, Tokyo, Japan) to compensate for the asymmetric mandibular arch and an asymmetrically bent archwire to move the maxillary molars distally. A skeletal anchorage system provided traction for intermaxillary elastics, and extractions were not needed. We alleviated the crowding and created an ideal occlusion with proper overjet, overbite, and anterior guidance with Class I canine and molar relationships. This method of treatment with an asymmetrically bent nickel-titanium alloy wire provided proper Class I occlusion and anterior guidance despite the mandibular deviation to the left and 3 mandibular incisors, without the need for extractions. Copyright © 2017 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

Mandibular reconstruction in adults: a review.

NARCIS (Netherlands)

Goh, B.T.; Lee, S.; Tideman, H.; Stoelinga, P.J.W.

2008-01-01

Mandibular defects may result from trauma, inflammatory disease and benign or malignant tumours. Mastication, speech and facial aesthetics are often severely compromised without reconstruction. The goal of mandibular reconstruction is to restore facial form and function, implying repair of

Assessment of the relationship between the mandibular third molar and the mandibular canal using panoramic radiograph and cone beam computed tomography

International Nuclear Information System (INIS)

Jung, Yun Hoa; Nah, Kyung Soo; Cho, Bong Hae

2008-01-01

The purpose of this study is to evaluate the position of the mandibular canal in relation to the mandibular third molar by cone beam CT in cases showing a close relationship between the third molar and the mandibular canal on the panoramic radiograph. The panoramic images and cone beam CT scans of 87 impacted mandibular third molars in 60 patients were evaluated to assess the tooth relationship to the mandibular canal. The clearness of the canal wall and the vertical depth of the lower third molar were evaluated on panoramic radiographs. The lower third molars were assessed using cone beam CT to determine the proximity and position of the canal relative to the roots. In the 66 cases where the canal wall was unclear on the panoramic radiographs, 58 (87.9%) of the third molars had contact between the canal and root; 34 (51.5%) canals were showed an inferior position and 22 (33.3%) showed a linguoinferior position on cone beam CT. Interruption of the canal wall on panoramic radiographs was highly predictive of contact between the mandibular canal and the third molar. Cross sectional CT may be indicated for localization of the mandibular canal in such cases.

Mandibular condyle position in cone beam computed tomography

Energy Technology Data Exchange (ETDEWEB)

Hwang, Hyoung Joo; Kim, Gyu Tae; Choi, Yong Suk; Hwang, Eui Hwan [Kyung Hee Univ. School of Dentistry, Seoul (Korea, Republic of)

2006-06-15

To evaluate position of the mandibular condyle within articular fossa in an asymptomatic population radiographically by a cone beam computed tomography. Cone beam computed tomography of 60 temporomandibular joints was performed on 15 males and 15 females with no history of any temporomandibular disorders, or any other orthodontic or photoconductors treatments. Position of mandibular condyle within articular fossa at centric occlusion was evaluated. A statistical evaluation was done using a SPSS. In the sagittal views, mandibular condyle within articular fossa was laterally located at central section. Mandibular condyles in the right and left sides were showed asymmetric positional relationship at medial, central, and lateral sections. Mandibular condyle within articular fossa in an asymptomatic population was observed non-concentric position in the sagittal and coronal views.

Calcium depletion in rabbit myocardium. Calcium paradox protection by hypothermia and cation substitution.

Science.gov (United States)

Rich, T L; Langer, G A

1982-08-01

The purpose of this study was to define further the basis of control of myocardial membrane permeability by further examination of the "calcium paradox." To this end, the protective effect of hypothermia and addition of micromolar amounts of divalent cations during the Ca-free perfusion period were studied. Damage during Ca++ repletion to the isolated arterially perfused, interventricular rabbit septum was assessed by contracture development, loss of developed tension, and loss of 42K and creatine kinase. Progressive hypothermia prolongs the time of Ca-free perfusion needed to cause similar 42K, creatine kinase and developed tension losses upon Ca++ repletion. Complete protection against the Ca-paradox after 30-60 minutes Ca-free perfusion is seen at 18 degree C. The inclusion of 50 microM Ca++ during 30 minutes "Ca-free" perfusion also provides complete protection during Ca++ repletion i.e., there was full mechanical recovery with no 42K or creatine kinase loss. Other divalent cations perfused in 50 microM concentrations during the Ca-free period exhibited variable ability to protect when Ca++ was reperfused. The order of effectiveness (Ca++ greater than Cd++ greater than Mn++ greater than Co++ greater than Mg++) was related to the crystal ionic radius, with those cations whose radii are closest to that of Ca++ (0.99 A) exerting the greatest protective effect. The cation sequence for effectiveness in Ca-paradox protection is the same sequence for potency of excitation-contraction uncoupling. The mechanism of hypothermic protection is likely a phase transition in the membrane lipids (from a more liquid to a less liquid state) which stabilizes membrane structure and preserves Ca++ permeability characteristics during the Ca-free period. The mechanism of protection via cation addition is perhaps a cation's ability to substitute for Ca++ (dependent on unhydrated crystal ionic radius) at critical sarcolemmal binding sites to preserve control of Ca++ permability during

[Stereomodel-assisted fibula free flap harvest and mandibular reconstruction: A technical note. Literature review of CAS and CAM applied to mandibular reconstruction.

Science.gov (United States)

Pauchot, J; Lachat, J; Floret, F; Badet, J-M; Tavernier, L; Aubry, S

2013-08-05

Mandibular reconstruction with fibula free flap harvest is currently the reference technique. Various preoperative processes have been developed to optimize this reconstruction. We report our experience with a simple, inexpensive, preoperative technique requiring a 3D printer, a device for maintaining mandibular reduction, a paper-cutting guide. Stereomodels of the mandible were obtained from computed tomography scan data and printed 3D in ABS. It allowed planning mandibular osteotomies, determine the angle between two bone fragments, and preoperatively modeling the osteosynthesis plate. A paper-cutting guide, and a simple device for maintaining mandibular reduction were also built. Two patients were operated on with this technique, with follow-up at 6 and 8 months. Reconstructions were successful with good clinical outcome in terms of mandibular contour and reconstructed segments positions. Preoperative planning of reconstruction may be used for mandibular osteotomies, fibular osteotomies, maintaining mandibular reduction, osteosynthesis, or placing implants for dental rehabilitation. The most complex procedures can virtually plan all these steps, but they are expensive and long to implement. Nevertheless, such procedures are quite expansive and require time not always compatible with carcinoma. Using a mandibular stereomodel is fast, easy, and cheap. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

Reliability of mandibular canines as indicators for sexual dichotomy.

Science.gov (United States)

Hosmani, Jagadish V; Nayak, Ramakant S; Kotrashetti, Vijayalakshmi S; S, Pradeep; Babji, Deepa

2013-02-01

Amongst the various calcified structures in the human body, teeth have gained lot of popularity in estimating the sex of an individual as they are highly resistant to destruction and decomposition. Using permanent mandibular canines many researchers have predicted a high level of accuracy in identifying the sex correctly. The purpose of our study was to gauge the effectiveness of mandibular canines in discerning sex. Fifty dental casts each of males and females were utilized for the study. Mesio-distal dimension and inter-canine distance of mandibular right and left canine was recorded using digital vernier caliper and mandibular canine index was calculated. The mean value of mesio-distal dimensions of right and left mandibular canine was slightly greater in males compared to females. The mandibular canine index was equal in both sexes. Inter-canine distance was marginally higher in males compared to females. Despite of higher values in males none of the parameters were statistically significant. The results herein bolster contemporary studies that mesio-distal dimensions of mandibular canines and mandibular canine index do not reflect sexual dimorphism and that its application should be discontinued in sex prediction among Indian populations. How to cite this article: Hosmani J V, Nayak R S, Kotrashetti V S, Pradeep S, Babji D. Reliability of Mandibular Canines as Indicators for Sexual Dichotomy. J Int Oral Health 2013; 5(1):1-7.

The effect of intraosseous local anesthesia of 4% articaine with 1:100,000 epinephrine on pulpal blood flow and pulpal anesthesia of mandibular molars and canines.

Science.gov (United States)

Vongsavan, Kadkao; Samdrup, Tshering; Kijsamanmith, Kanittha; Rirattanapong, Praphasri; Vongsavan, Noppakun

2018-05-10

The aim of this study was to determine the effect of intraosseous (IO) anesthesia with 4% articaine and 1:100,000 epinephrine on pulpal blood flow (PBF) and pulpal anesthesia of mandibular first molars and canines in human subjects. Ten healthy volunteers with intact mandibular first molar and canine were given an osteocentral technique of IO injection using the Quick Sleeper 5 system and 4% articaine with 1:100,000 epinephrine at distal site of mandibular first molar. The PBF was monitored by a laser Doppler flowmeter (LDF). Pulpal anesthesia was assessed with an electric pulp tester (EPT). IO injection caused a decrease in PBF in molars from 6.31 ± 3.85 perfusion units (P.U.) before injection to 2.51 ± 2.53 P.U. 1 min after injection (P anesthesia in the molars, the mean onset was 2.40 ± 0.84 min and the mean duration was 38 ± 16.19 min. In the canines, there was a decrease in the sensitivity to EPT but complete pulpal anesthesia was not achieved. IO injection distal to mandibular first molar caused a decrease in PBF and successful pulpal anesthesia in first molar, but not in canine. Both PBF and EPT readings returned to normal, suggesting that pulpal ischemia may not occur. IO anesthesia is safe to use as a primary technique in teeth with normal pulp.

Mandibular Deformity Correction by Distraction Osteogenesis

Directory of Open Access Journals (Sweden)

Md Asaduzzaman

2011-02-01

Full Text Available Distraction osteogenesis (DO is a biological process of new bone formation. It could be used as an alternative treatment method for the correction of mandibular hypoplastic deformity. Modern distraction osteogenesis evolved primarily from the work of Gavriel llizarov. DO has been first applied to craniofacial region since McCarthy et al. In this case report, the patient was 17 years old male with bird face deformity due to hypoplasia of mandible resulted from bilateral TMJ ankylosis due to the fracture of both condyle at the age of 4 years. Patient’s intraincisal opening was absent 1 year back. He underwent condylectomy in both sides to release the ankylosis and to increase intraincisal opening. His mandibular length was markedly short. To increase his mandibular antero-posterior length, mandibular body distraction was done in Oral and Maxillofacial Surgery department, BSMMU. Through this procedure length of the body of mandibule was increased by 10 mm, occlusion was edge to edge and his lower facial appearance increased markedly. Mandibular body distraction osteogenesis was considerably effective when performed in a hypoplastic mandible to facilitate post-operative functional and esthetic restoration. Long term follow-up is necessary to evaluate relapse and complications. DOI: 10.3329/bsmmuj.v3i2.7061BSMMU J 2010; 3(2: 103-106

Comparative quantitative monitoring of rabbit haemorrhagic disease viruses in rabbit kittens.

Science.gov (United States)

Matthaei, Markus; Kerr, Peter J; Read, Andrew J; Hick, Paul; Haboury, Stephanie; Wright, John D; Strive, Tanja

2014-06-09

Only one strain (the Czech CAPM-v351) of rabbit haemorrhagic disease virus (RHDV) has been released in Australia and New Zealand to control pest populations of the European rabbit O. cuniculus. Antigenic variants of RHDV known as RHDVa strains are reportedly replacing RHDV strains in other parts of the world, and Australia is currently investigating the usefulness of RHDVa to complement rabbit biocontrol efforts in Australia and New Zealand. RHDV efficiently kills adult rabbits but not rabbit kittens, which are more resistant to RHD the younger they are and which may carry the virus without signs of disease for prolonged periods. These different infection patterns in young rabbits may significantly influence RHDV epidemiology in the field and hence attempts to control rabbit numbers. We quantified RHDV replication and shedding in 4-5 week old rabbits using quantitative real time PCR to assess their potential to shape RHDV epidemiology by shedding and transmitting virus. We further compared RHDV-v351 with an antigenic variant strain of RHDVa in kittens that is currently being considered as a potential RHDV strain for future release to improve rabbit biocontrol in Australia. Kittens were susceptible to infection with virus doses as low as 10 ID50. Virus growth, shedding and transmission after RHDVa infection was found to be comparable or non-significantly lower compared to RHDV. Virus replication and shedding was observed in all kittens infected, but was low in comparison to adult rabbits. Both viruses were shed and transmitted to bystander rabbits. While blood titres indicated that 4-5 week old kittens mostly clear the infection even in the absence of maternal antibodies, virus titres in liver, spleen and mesenteric lymph node were still high on day 5 post infection. Rabbit kittens are susceptible to infection with very low doses of RHDV, and can transmit virus before they seroconvert. They may therefore play an important role in RHDV field epidemiology, in

Accumulation of 125I-factor XI in atheroma of rabbit with hereditary hyperlipidemia (WHHL-rabbit)

International Nuclear Information System (INIS)

Komiyama, Y.; Masuda, M.; Murakami, T.; Nishikado, H.; Egawa, H.; Nishimura, T.; Morii, S.; Murata, K.

1989-01-01

We have studied the turnover and accumulation of rabbit factor XI (F.XI) in atherosclerotic lesion in Watanabe-hereditable hyperlipidemic rabbit (WHHL rabbit) to reveal the participation of blood coagulation in atherosclerotic lesion. Rabbit F.XI was iodinated and administered intravenously to WHHL rabbits and Japanese white rabbits. The turnover of 125 I-rabbit F.XI was significantly faster in WHHL rabbits (T1/2 = 2.84 +/- 0.44 days) than in normal rabbits (T1/2 = 4.44 +/- 0.42 days). The thoracic aorta of WHHL rabbit was strongly labelled with 125 I-rabbit F.XI, in sections obtained after 5 days by en-face autoradiography, whereas no radioactivity was detected in normal aorta. By an immunohistochemical study of WHHL rabbit aorta, we confirmed that many F.XI- and fibrin-related compounds existed in the atheroma, whereas albumin did not in these area. These results suggest that the activation of F.XI proceeds on the atherosclerotic lesions of WHHL rabbits

Allergy to Rabbits. 1

International Nuclear Information System (INIS)

Price, J.A.; Longbottom, J.L.

1986-01-01

Investigations have been carried out into the presence of antibody light chains in rabbit allergenic extracts and the interference in RAST and crossed-radioimmunoelectrophoresis (XRIE) caused by antibodies directed against them. A ''non-specific'' uptake of radioactivity in XRIE has been demonstrated to be caused by direct cross-linking of the 125 I rabbit anti-human IgE by the sheep antibodies in the immunoprecipitate of rabbit light chains. Preincubation with normal rabbit serum blocked this direct uptake of the labelled antibody and enabled specific IgE uptake on the light chains to be demonstrated for rabbit allergic sera. Verification of the allergenicity of the light chains was obtained from a specific light chain RAST. Elution from a Sephacryl S-200 gel filtration column indicated a MW of approx. 50Kd and confirmation of the components as light chain dimers, not Fab fragments, was obtained by allotyping for loci present on heavy chains and light chains in the Fab region. Light chains were detected in urine from rabbits of all ages and in an extract of dust collected in a rabbit housing area. No background staining was observed in XRIE using rabbit antisera, either with rabbit allergic sera with specific IgE or with a human serum containing specific IgG antibodies to rabbit IgG. This latter serum also showed no evidence of uptake on all immunoprecipitates in systems using rabbit antisera, and did not give false positive RAST results when the labelled rabbit anti-human IgE contained unlabelled rabbit IgG. Those sera with specific IgE to light chains showed no uptake in XRIE using rabbit antisera, indicating that the IgE was possibly specific for epitopes revealed by the dissociation on the whole IgG molecule. (author)

Malignant mandibular tumors: two case reports of rare mandibular ...

African Journals Online (AJOL)

Arun Kumar Agnihotri

2014-02-26

Feb 26, 2014 ... present two cases of rare malignant mandibular tumors in a single institution. KEY WORDS: .... Spiculated osteoblastic periosteal reaction was noted with mild ... displacement of right 2nd premolar and 2nd molar teeth were ...

Rabbit analgesia.

Science.gov (United States)

Barter, Linda S

2011-01-01

With the increasing popularity of rabbits as household pets, the complexity of diagnostic and surgical procedures performed on rabbits is increasing, along with the frequency of routine surgical procedures. More practitioners are faced with the need to provide adequate analgesia for this species. Preemptive analgesia prior to planned surgical interventions may reduce nervous system changes in response to noxious input, as well as reduce postoperative pain levels and analgesic drug requirements. Concurrent administration of analgesic drugs to anesthetized rabbits undergoing painful procedures is warranted both pre- and intraoperatively as well as postoperatively. This article discusses the neuropharmacologic and pharmacologic aspects of pain in rabbits, and reviews current protocols for the use of analgesic drugs. Published by Elsevier Inc.

Myocardial kinetics of hexakis (trimethylphosphite) technetium-99m (I) chloride (Tc-TMP) in rats, rabbits, dogs, cats and pigs

International Nuclear Information System (INIS)

Robbins, M.S.; Adams, M.D.

1984-01-01

Tc-TMP is readily taken up by the myocardium following intravenous administration to rats and dogs. In order to assess its potential as a myocardial perfusion imaging agent, the biodistribution and pharmacokinetics of Tc-TMP were evaluated following intravenous administration to rats, rabbits, dogs, cats and miniature pigs. Rats and rabbits were killed at several time points within a 24 hr period after treatment and tissue samples were assayed for radioactivity. In rats, estimated heart, liver and lung half-lives were 14.4 hr, 24 min and 40 min, respectively. In rabbits, 0.6% dose/g was observed in the heart at 30 min. Corresponding heart/blood, heart/liver and heart/lung ratios were 39.1, 10.7 and 5.1. Gamma camera imaging experiments were conducted in rabbits, dogs, cats and pigs over a 1-2 hr period following administration of Tc-TMP. All species exhibited myocardial uptake resulting in sustained visualization, although myocardial image intensity was less pronounced in the pig compared to the other species. Regions of interest were selected over the heart, liver and background, and time-activity curves were generated. Minimal myocardial clearance was observed in all species during the imaging time course. Hepatic activity was rapidly cleared in rabbits and pigs (t1/2 < 1.0 hr) resulting in improved heart/liver ratios at later time intervals. The myocardial accumulation and retention of Tc-TMP, demonstrated in five species, supports clinical evaluation as a myocardial imaging agent

The efficacy of supplemental intraosseous anesthesia after insufficient mandibular block

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Samir Prohić

2005-02-01

Full Text Available It is a well-known scientific fact that only a small percentage of infiltration of inferior alveolar nerve is clinically proven to be efficient. The objective of this study was to determine the anesthetic efficacy of supplemental intraosseous injection, used after the insufficient classical mandibular block that didn't provide deep pulp anesthesia of mandibular molar planed for extraction. The experimental teeth consisted of 98 mandibular molars with clinical indication for extraction. Based on the history of disease, we indicated the extraction of the tooth. After that each tooth was tested with a electric pulp tester P1. We tested the pulp vitality and precisely determined the level of vitality. After that, each patient received classical mandibular block, and the pulp vitality was tested again. If the pulp tester indicated negative vitality for the certain mandibular molar, and the patient didn't complain about pain or discomfort during the extraction, the molar was extracted and the result was added to anesthetic success rate for the classical mandibular block. If, five minutes after receiving the mandibular block, the pulp tester indicated positive vitality (parameters of vitality or the patient complained about pain or discomfort (parameters of pain and discomfort, we used the Stabident intraosseous anesthesia system. Three minutes after the application of supplemental intraosseous injection the molar was tested with the pulp tester again. The anesthetic solution used in both anesthetic techniques is lidocaine with 1:100.000 epinephrine. The results of this study indicate that the anesthetic efficacy of the mandibular block is 74.5%, and that supplemental intraosseous anesthesia, applied after the insufficient mandibular block, provides pulpal anesthesia in 94.9% of mandibular molars. The difference between anesthetic efficacy of the classical mandibular block and anesthetic efficacy of the supplemental intraosseous anesthesia, applied

The efficacy of supplemental intraosseous anesthesia after insufficient mandibular block.

Science.gov (United States)

Prohić, Samir; Sulejmanagić, Halid; Secić, Sadeta

2005-02-01

It is a well-known scientific fact that only a small percentage of infiltration of inferior alveolar nerve is clinically proven to be efficient. The objective of this study was to determine the anesthetic efficacy of supplemental intraosseous injection, used after the insufficient classical mandibular block that didn't provide deep pulp anesthesia of mandibular molar planed for extraction. The experimental teeth consisted of 98 mandibular molars with clinical indication for extraction. Based on the history of disease, we indicated the extraction of the tooth. After that each tooth was tested with a electric pulp tester P1. We tested the pulp vitality and precisely determined the level of vitality. After that, each patient received classical mandibular block, and the pulp vitality was tested again. If the pulp tester indicated negative vitality for the certain mandibular molar, and the patient didn't complain about pain or discomfort during the extraction, the molar was extracted and the result was added to anesthetic success rate for the classical mandibular block. If, five minutes after receiving the mandibular block, the pulp tester indicated positive vitality (parameters of vitality) or the patient complained about pain or discomfort (parameters of pain and discomfort), we used the Stabident intraosseous anesthesia system. Three minutes after the application of supplemental intraosseous injection the molar was tested with the pulp tester again. The anesthetic solution used in both anesthetic techniques is lidocaine with 1:100.000 epinephrine. The results of this study indicate that the anesthetic efficacy of the mandibular block is 74.5%, and that supplemental intraosseous anesthesia, applied after the insufficient mandibular block, provides pulpal anesthesia in 94.9% of mandibular molars. The difference between anesthetic efficacy of the classical mandibular block and anesthetic efficacy of the supplemental intraosseous anesthesia, applied after the

Topographical evaluation of the mandibular canal through panoramic radiograph

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Ingrid Macedo Oliveira

2016-10-01

Full Text Available The mandibular canal is located inside the body of the mandible and may have anatomical variations. The topographic knowledge of the mandibular canal by the Dental surgeons is fundamental to achieving success in surgical planning, anesthetics and clinical interventions involving the jaw. To study the anatomy of the mandibular canal through panoramic radiographs. A retrospective descriptive study, developed after review and approval by the Ethics and Research Committee with the number of opinion 431095. Were analyzed 252 panoramic radiographs of patients of male and female attended in dental clinics UNINOVAFAPI University Center, Teresina-Pi, Brazil. The radiographs were analyzed with the aid of a light box and each antimere the jaw was observed separately. The classification of Nortjé and Langlais for description of the topography of the mandibular canal were used. Descriptive statistical analysis was performed with SPSS version 18.0. There was a prevalence of 38.89% in both antimeres, of mandibular channel the Type II. The type IV was present in 25.4% in the right hemi-arch and 26.6% on the left. Mandibular canal with unilateral bifurcation was observed in 0.77% of the sample and molar straight channel has not been identified. We observed anatomical variations as for the number and path, of the mandibular canal with the highest prevalence of Types II and IV, and the absence of bifurcations. Most was mandibular channels showed no bifurcation. The panoramic radiograph showed up an aid important to identify the mandibular canal and its variations.

Prosthodontic management of mandibular deviation using palatal ramp appliance

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Prince Kumar

2012-08-01

Full Text Available Segmental resection of the mandible generally results in deviation of the mandible to the defective side. This loss of continuity of the mandible destroys the balance of the lower face and leads to decreased mandibular function by deviation of the residual segment toward the surgical site. Prosthetic methods advocated to reduce or eliminate mandibular deviation include intermaxillary fixation, removable mandibular guide flange, palatal ramp, implant-supported prosthesis and palatal guidance restorations which may be useful in reducing mandibular deviation and improving masticatory performance and efficiency. These methods and restorations would be combined with a well organized mandibular exercise regimen. This clinical report describes the rehabilitation following segmental mandibulectomy using palatal ramp prosthesis.

Perfusion abnormalities in congenital and neoplastic pulmonary disease: comparison of MR perfusion and multislice CT imaging

International Nuclear Information System (INIS)

Boll, Daniel T.; Lewin, Jonathan S.; Young, Philip; Gilkeson, Robert C.; Siwik, Ernest S.

2005-01-01

The aim of this work was to assess magnetic resonance (MR) perfusion patterns of chronic, nonembolic pulmonary diseases of congenital and neoplastic origin and to compare the findings with results obtained with pulmonary, contrast-enhanced multislice computed tomography (CT) imaging to prove that congenital and neoplastic pulmonary conditions require MR imaging over the pulmonary perfusion cycle to successfully and directly detect changes in lung perfusion patterns. Twenty-five patients underwent concurrent CT and MR evaluation of chronic pulmonary diseases of congenital (n=15) or neoplastic (n=10) origin. Analysis of MR perfusion and contrast-enhanced CT datasets was realized by defining pulmonary and vascular regions of interest in corresponding positions. MR perfusion calculated time-to-peak enhancement, maximal enhancement and the area under the perfusion curve. CT datasets provided pulmonary signal-to-noise ratio measurements. Vessel centerlines of bronchial arteries were determined. Underlying perfusion type, such as pulmonary arterial or systemic arterial supply, as well as regions with significant variations in perfusion were determined statistically. Analysis of the pulmonary perfusion pattern detected pulmonary arterial supply in 19 patients; six patients showed systemic arterial supply. In pulmonary arterial perfusion, MR and multislice CT imaging consistently detected the perfusion type and regions with altered perfusion patterns. In bronchial arterial supply, MR perfusion and CT imaging showed significant perfusion differences. Patients with bronchial arterial supply had bronchial arteries ranging from 2.0 to 3.6 mm compared with submillimeter diameters in pulmonary arterial perfusion. Dynamic MR imaging of congenital and neoplastic pulmonary conditions allowed characterization of the pulmonary perfusion type. CT imaging suggested the presence of systemic arterial perfusion by visualizing hypertrophied bronchial arteries. (orig.)

Electrolyte and protein secretion by the perfused rabbit mandibular gland stimulated with acetylcholine or catecholamines

DEFF Research Database (Denmark)

Case, R M; Conigrave, A D; Novak, I

1980-01-01

stimulation, the rate of protein secretion fell off much faster than the rate of fluid secretion.7. The beta-adrenergic agonist isoproterenol evoked a fluid secretory response only equal to about 5% of that evoked by acetylcholine, but still the response declined during continued stimulation. The electrolyte...... composition of isoproterenol-evoked saliva was vastly different from that evoked by acetylcholine, being particularly rich in K and HCO(3). The isoproterenol-evoked saliva was also extremely rich in protein so that the total protein secretion evoked by isoproterenol was much greater than that evoked...... unstimulated or evoked by acetylcholine or eserine, could be blocked completely by atropine.4. During prolonged stimulation with acetylcholine, the fluid secretory response declined rapidly over a period of about 15 min from an initial high value to a much lower plateau value. After 3 or more hours...

Skeletal maturity assessment using mandibular canine calcification stages

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Vildana Džemidžić

2016-11-01

Full Text Available Objective. The aims of this study were: to investigate the relationship between mandibular canine calcification stages and skeletal maturity; and to evaluate whether the mandibular canine calcification stages may be used as a reliable diagnostic tool for skeletal maturity assessment. Materials and methods. This study included 151 subjects: 81 females and 70 males, with ages ranging from 9 to 16 years (mean age: 12.29±1.86 years. The inclusion criteria for subjects were as follows: age between 9 and 16 years; good general health without any hormonal, nutritional, growth or dental development problems. Subjects who were undergoing or had previously received orthodontic treatment were not included in this study. The calcification stages of the left permanent mandibular canine were assessed according to the method of Demirjian, on panoramic radiographs. Assessment of skeletal maturity was carried out using the cervical vertebral maturation index (CVMI, as proposed by the Hassel-Farman method, on lateral cephalograms. The correlation between the calcification stages of mandibular canine and skeletal maturity was estimated separately for male and female subjects. Results. Correlation coefficients between calcification stages of mandibular canine and skeletal maturity were 0.895 for male and 0.701 for female subjects. Conclusions. A significant correlation was found between the calcification stages of the mandibular canine and skeletal maturity. The calcification stages of the mandibular canine show a satisfactory diagnostic performance only for assessment of pre-pubertal growth phase.

Effects of vasopressin on the isolated perfused human collecting tubule.

Science.gov (United States)

Yanagawa, N; Trizna, W; Bar-Khayim, Y; Fine, L G

1981-05-01

Cortical collecting tubules (CCT) were dissected from the surviving normal tissue of human kidneys removed at operation for either carcinoma or calculus. These CCT's were perfused in vitro shortly after the nephrectomy was performed. Transtubular potential differences in different tubules varied from +3.2 to -2.0 mV and were reduced towards zero by lowering the temperature or by adding ouabain to the bath. In the absence of vasopressin, tubules were essentially impermeable to water with extremely low net water fluxes even in the presence of a transtubular osmotic gradient. Addition of vasopressin to the bath caused the transtubular osmotic water permeability coefficient to increase to values of 125, 175, and 155 X 10(-4) cm/sec in three tubules thus studied. These results demonstrate close similarities between the human CCT and the more extensively studied rabbit CCT.

Ultrasound and multidetector computed tomography of mandibular ...

African Journals Online (AJOL)

Because of local invasivity and high metastatic potential, preoperative imaging evaluation of mandibular region and tumoral staging is essential along with biopsy sampling. The present manuscript describes the ultrasound and computed tomographic imaging findings of mandibular gland adenocarcinoma in two dogs and ...

Influence of mandibular length on mouth opening

NARCIS (Netherlands)

Dijkstra, PU; Hof, AL; Stegenga, B; De Bont, LGM

Theoretically, mouth opening not only reflects the mobility of the temporomandibular joints (TMJs) but also the mandibular length. Clinically, the exact relationship between mouth opening, mandibular length, and mobility of TMJs is unclear. To study this relationship 91 healthy subjects, 59 women

Laser doppler perfusion imaging

International Nuclear Information System (INIS)

Waardell, K.

1992-01-01

Recording of tissue perfusion is important in assessing the influence of peripheral vascular diseases on the microcirculation. This thesis reports on a laser doppler perfusion imager based on dynamic light scattering in tissue. When a low power He-Ne laser beam sequentally scans the tissue, moving blood cells generate doppler components in the back-scattered light. A fraction of this light is detected by a photodetector and converted into an electrical signal. In the processor, a signal proportional to the tissue perfusion at each measurement site is calculated and stored. When the scanning procedure is completed, a color-coded perfusion image is presented on a monitor. To convert important aspects of the perfusion image into more quantitative parameters, data analysis functions are implemented in the software. A theory describing the dependence of the distance between individual measurement points and detector on the system amplification factor is proposed and correction algorithms are presented. The performance of the laser doppler perfusion imager was evaluated using a flow simulator. A linear relationship between processor output signal and flow through the simulator was demonstrated for blood cell concentrations below 0.2%. The median sampling depth of the laser beam was simulated by a Monte Carlo technique and estimated to 235 μm. The perfusion imager has been used in the clinic to study perfusion changes in port wine stains treated with argon laser and to investigate the intensity and extension of the cutaneous axon reflex response after electrical nerve stimulation. The fact that perfusion can be visualized without touching the tissue implies elimination of sterilization problems, thus simplifying clinical investigations of perfusion in association with diagnosis and treatment of peripheral vascular diseases. 22 refs

Incidence and characteristics of mandibular accessory canals: A radiographic investigation.

Science.gov (United States)

Borgonovo, Andrea Enrico; Taschieri, Silvio; Vavassori, Virna; Re, Dino; Francetti, Luca; Corbella, Stefano

2017-11-01

The aim of the present study was to explore, through tridimensional reconstructions of cone-beam computed tomography (CBCT) scans, the presence and the characteristics of mandibular accessory canals. For each included participant, the presence of accessory canals was recorded. The diameter of the canal, as well as the distance between the canal walls and the walls of the mandibular bone (lingual, buccal, cranial and caudal), were measured and recorded. Mandibular accessory canals could be found in 8.8% of participants. Retromolar canals were the most frequently found accessory mandibular canals. Accessory mandibular canals were found in a relatively high number of participants through the examination of CBCT scans and tridimensional reconstruction. The presence of such structures should be considered cautiously when planning and performing surgical interventions in mandibular area. © 2017 John Wiley & Sons Australia, Ltd.

Radiosynthesis and preclinical evaluation of [{sup 18}F] 4-(2-fluoroethoxy)-2H-chromen-2-one as a novel myocardial perfusion imaging agent

Energy Technology Data Exchange (ETDEWEB)

Bhusari, Arun M.; Degani, Mariam S. [Institute of Chemical Technology, Mumbai (India). Dept. of Pharmaceutical Sciences and Technology; Lakshminarayanan, N.; Pawar, Yogita P.; Moghe, Surendra H.; Rajan, M.G.R. [Bhabha Atomic Research Centre, Mumbai (India). Radiation Medicine Center

2017-07-01

Recently we developed [{sup 18}F] 4-(2-fluoroethoxy)-2H-chromen-2-one as a novel {sup 18}F myocardial perfusion imaging radiotracer. It was synthesized in good radiochemical yield (>90%). The total time from radiosynthesis to its purification was less than 40 min, with excellent radiochemical purity (≥99%). It showed good stability over a period of 5 h at room temperature. The partition coefficient (log P) of radiotracer was found to be 2.70, suggesting the lipophilic nature of radiotracer. Ex vivo biodistribution study of radiotracer in normal Wistar rats for 30 min post-injection, demonstrated a good heart uptake (>1.3% ID/g) and favorable pharmacokinetics. Additionally, the radiotracer showed significant excretion (>11% ID) by liver, which is indicative of its rapid clearance. Further, in vivo biodistribution study of radiotracer in New Zealand White rabbit provided the clear PET/CT images of cardiomyocytes and myocardial perfusion. All these experimental findings suggest that [{sup 18}F] 4-(2-fluoroethoxy)-2H-chromen-2-one could be used as a potential hit for myocardial perfusion imaging.

Protection of skin with subcutaneous administration of 5% dextrose in water during superficial radiofrequency ablation in a rabbit model.

Science.gov (United States)

Guo, Hui; Liu, Xia-Lei; Wang, Yu-Ling; Li, Jing-Yi; Lu, Wu-Zhu; Xian, Jian-Zhong; Zhang, Bai-Meng; Li, Jian

2014-06-01

This study was to evaluate the efficacy of subcutaneous administration of 5% dextrose in water (D5W), to prevent skin injury during radiofrequency (RF) ablation. Twenty-four rabbits were divided into three groups: a pre-injection group, a perfusion group, and a control group. Ablative zones were created in the superficial part of the thigh muscle for 6 min. A needle was placed subcutaneously for injection of D5W, and a thermal sensor was positioned nearby for real-time temperature monitoring. The sizes of the ablative zones were measured by contrast-enhanced ultrasonography, and severity of the observed skin injury were scored semi-quantitatively and compared. The highest temperature, the duration of the temperature above 50 °C, and the rise time of the post-procedure temperature were all highest in the control group (p skin injury was most severe in the control group (p skin injury of the pre-injection group and the perfusion group (p = 0.091), while the skin injury of the perfusion group was less severe than that of the pre-injection group on post-procedure day 14 (p = 0.004). No significant difference was found in the sizes of the ablative zones among the groups (p = 0.720). Subcutaneous perfusion with D5W is effective in protecting the skin against burns during RF ablation without compromising the effect of ablation.

Evaluation of the relationship between mandibular third molar and mandibular canal by different algorithms of cone-beam computed tomography.

Science.gov (United States)

Mehdizadeh, Mojdeh; Ahmadi, Navid; Jamshidi, Mahsa

2014-11-01

Exact location of the inferior alveolar nerve (IAN) bundle is very important. The aim of this study is to evaluate the relationship between the mandibular third molar and the mandibular canal by cone-beam computed tomography. This was a cross-sectional study with convenience sampling. 94 mandibular CBCTs performed with CSANEX 3D machine (Soredex, Finland) and 3D system chosen. Vertical and horizontal relationship between the mandibular canal and the third molar depicted by 3D, panoramic reformat view of CBCT and cross-sectional view. Cross-sectional view was our gold standard and other view evaluated by it. There were significant differences between the vertical and horizontal relation of nerve and tooth in all views (p < 0.001). The results showed differences in the position of the inferior alveolar nerve with different views of CBCT, so CBCT images are not quite reliable and have possibility of error.

Split-Framework in Mandibular Implant-Supported Prosthesis

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Danny Omar Mendoza Marin

2015-01-01

Full Text Available During oral rehabilitation of an edentulous patient with an implant-supported prosthesis, mandibular flexure must be considered an important biomechanical factor when planning the metal framework design, especially if implants are installed posterior to the interforaminal region. When an edentulous mandible is restored with a fixed implant-supported prosthesis connected by a fixed full-arch framework, mandibular flexure may cause needless stress in the overall restorative system and lead to screw loosening, poor fit of prosthesis, loss of the posterior implant, and patient’s discomfort due to deformation properties of the mandible during functional movements. The use of a split-framework could decrease the stress with a precise and passive fit on the implants and restore a more natural functional condition of the mandible, helping in the longevity of the prosthesis. Therefore, the present clinical report describes the oral rehabilitation of an edentulous patient by a mandibular fixed implant-supported prosthesis with a split-framework to compensate for mandibular flexure. Clinical Significance. The present clinical report shows that the use of a split-framework reduced the risk of loss of the posterior implants or screws loosening with acceptable patient comfort over the period of a year. The split-framework might have compensated for the mandibular flexure during functional activities.

Pediatric mandibular fractures treated by rigid internal fixation.

Science.gov (United States)

Wong, G B

1993-09-01

Mandibular fractures in the pediatric patient population are relatively uncommon. These patients present with their own unique treatment requirements. Most fractures have been treated conservatively by dental splints. Closed reduction techniques with maxillomandibular fixation (MMF) in very young children can pose several concerns, including cooperation, compliance and adequate nutritional intake. Rigid internal fixation of unstable mandibular fractures using miniplates and screws circumvents the need for MMF and allows immediate jaw mobilization. At major pediatric trauma institutions, there has been an increasing trend toward the use of this treatment when open reduction is necessary. This article presents a report of a five-year-old child who presented with bilateral mandibular fractures and was treated by rigid internal fixation and immediate mandibular mobilization.

Bifid mandibular canal: a rare or underestimated entity?

Directory of Open Access Journals (Sweden)

Ibrahim Nasseh

2016-10-01

Full Text Available One of the rare anatomical variations that can be of significant importance for the dentist is the bifid mandibular canal. Many complications can occur from this condition such as failure of anesthesia when performing inferior alveolar nerve block, difficulties during the surgical extraction of the third mandibular molar, and during implants placement. Therefore, good knowledge of this condition is essential. In this report, we describe the radiographic finding of a unilateral bifid mandibular canal.

Mandibular incisor apicoectomy in a Canadian Beaver.

Science.gov (United States)

Steenkamp, Gerhard; Venter, Leon; Crossley, David; Buss, Peter

2009-01-01

A 52-month-old Canadian beaver was presented for treatment of lip trauma resulting from overgrowth of the right mandibular incisor tooth following earlier loss of the right maxillary incisor tooth. Extraction of the affected tooth was considered, but rejected due to the length of the embedded portion of rodent mandibular incisor teeth. The lip injury was managed by crown reduction (odontoplasty) of the overgrowing incisor tooth pending a more permanent treatment plan. A 2-cm apicoectomy of the right mandibular incisor tooth was performed to arrest growth of the tooth when the beaver was 82-months-old. The remainder of the tooth continued to erupt and was completely expelled during a 9-month period with one additional odontoplasty being required. The beaver continued to feed normally with just the left maxillary and mandibular incisor teeth until its death at 118-months, with odontoplasty performed twice on the remaining incisor teeth during the 30-months following exfoliation.

Evaluation of mandibular morphology in different facial types

Directory of Open Access Journals (Sweden)

Rajat Mangla

2011-01-01

Full Text Available The purpose of this study was to evaluate mandibular morphology in different facial types using various parameters. This study was conducted on lateral cephalograms of a total of 110 subjects, which included 55 males and 55 females between the age of 18-25 years having a mean of 22.3 years for males and 21.5 years for females. The sample was divided into normodivergent, hypodivergent, and hyperdivergent subgroups based on Jarabak′s ratio. Symphysis height, depth, ratio (height/depth and angle, antegonial notch depth, ramal height and width, mandibular depth, upper, lower, and total gonial angle, and mandibular arc angle were analyzed statistically and graphically. It was found that the mandible with the vertical growth pattern was associated with a symphysis with large height, small depth, large ratio, small angle, decreased ramus height and width, smaller mandibular depth, increased gonial angle, and decreased mandibular arc angle in contrast to mandible with a horizontal growth pattern. Sexual dichotomy was found with mean symphysis height and depth in the female sample being smaller than in the male sample, but symphysis ratio was larger in the female sample; males having greater ramus height and width, mandibular depth than females. The mandible seemed to have retained its infantile characteristics with all its processes underdeveloped in hyperdivergent group.

Relationship between cervical vertebral maturation and mandibular growth.

Science.gov (United States)

Ball, Gina; Woodside, Donald; Tompson, Bryan; Hunter, W Stuart; Posluns, James

2011-05-01

The cervical vertebrae have been proposed as a method of determining biologic maturity. The purposes of this study were to establish a pattern of mandibular growth and to relate this pattern to the stages of cervical vertebral maturation. Cephalometric radiographs, taken annually from ages 9 to 18 years, were evaluated for 90 boys from the Burlington Growth Center, Toronto, Ontario, Canada. Mandibular lengths were measured from articulare to gnathion, and incremental growth was determined. Cervical vertebral maturation stages were assessed by using a 6-stage method. Advanced, average, and delayed maturation groups were established. The prepubertal mandibular growth minimum velocity occurred during cervical stages 1 through 4 (P = 0.7327). Peak mandibular growth velocity occurred most frequently during stage 4 in all 3 maturation groups, with a statistical difference in the average and delayed groups (P cervical stages 1 through 6 does not occur annually; time spent in each stage varies depending on the stage and the maturation group. Cervical vertebral maturation stages cannot accurately identify the mandibular prepubertal growth minimum and therefore cannot predict the onset of the peak in mandibular growth. The cervical vertebral maturation stages should be used with other methods of biologic maturity assessment when considering both dentofacial orthopedic treatment and orthognathic surgery. Copyright © 2011 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

Impacted mandibular third molars and their influence on mandibular angle and condyle fractures--a retrospective study.

Science.gov (United States)

Gaddipati, Rajasekhar; Ramisetty, Sudhir; Vura, Nandagopal; Kanduri, Rajeev Reddy; Gunda, Vinay Kumar

2014-10-01

Previous retrospective analyses prove that impacted mandibular third molars (M3s) increase the risk of angle fractures and decrease the risk of concomitant fractures to the condyle. A retrospective cohort was designed for patients reported to the Department of Oral and Maxillofacial Surgery from January 2011 till June 2013. The study variables are presence or absence of third molar, if it is present, their position, classified using the Pell and Gregory system; angulation, classified using Shiller's method. The outcome variables were angle and condyle fractures. Hospital records and panoramic radiographs were used to determine and classify these variables. The study sample comprised of 118 mandibular angle and condyle fractures in 110 patients. Database was constructed and analysed using SPSS version 10.0. This present retrospective study concluded that the presence of impacted third molar predisposes the angle to fracture and reduces the risk of a concomitant condylar fracture. However absence of impacted third molar increases the risk of condylar fracture. The highest incidence of angle fracture was observed in position A impacted mandibular third molars. And there is no significant relationship, concerning ramus position and angulation of impacted mandibular third molars with the angle fracture. Copyright © 2014 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

Resolution of neurosensory deficit after mandibular orthognathic surgery: A prospective longitudinal study.

Science.gov (United States)

Alolayan, Albraa Badr; Leung, Yiu Yan

2017-05-01

To investigate the longitudinal resolution of neurosensory deficit (NSD) and the possible risk factors that might contribute to NSD following mandibular orthognathic procedures. A prospective longitudinal observational study on patients who had mandibular orthognathic procedures was performed. Standardized neurosensory assessments were performed. The 2 years longitudinal resolution and risk factors of NSD including patients' age and gender, specific mandibular procedures and surgeons' experience were analyzed. 66 patients (44 females) with 132 sides of mandibular procedures were enrolled in the study. Surgical procedures included mandibular ramus surgery, anterior mandibular surgery, or the combination of the two. The overall occurrences of subjective NSD improved from 78.8% at postoperative 2 weeks to 13.8% at post-operative 2 years. Combinations of ramus surgery and anterior mandibular surgery increased the risk of NSD at the first three post-operative months (p orthognathic surgery. The occurrence of NSD after mandibular orthognathic procedures reduced progressively within the post-operative 2 years. Combination of mandibular ramus surgery and anterior mandibular surgery increased the risk of NSD in the early post-operative period. Copyright © 2017 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

Morphometric study on mandibular foramen and incidence of accessory mandibular foramen in mandibles of south Indian population and its clinical implications in inferior alveolar nerve block.

Science.gov (United States)

Shalini, R; RaviVarman, C; Manoranjitham, R; Veeramuthu, M

2016-12-01

The mandibular foramen is a landmark for procedures like inferior alveolar nerve block, mandibular implant treatment, and mandibular osteotomies. The present study was aimed to identify the precise location of the mandibular foramen and the incidence of accessory mandibular foramen in dry adult mandibles of South Indian population. The distance of mandibular foramen from the anterior border of the ramus, posterior border of the ramus, mandibular notch, base of the mandible, third molar, and apex of retromolar trigone was measured with a vernier caliper in 204 mandibles. The mean distance of mandibular foramen from the anterior border of ramus of mandible was 17.11±2.74 mm on the right side and 17.41±3.05 mm on the left side, from posterior border was 10.47±2.11 mm on the right side and 9.68±2.03 mm on the left side, from mandibular notch was 21.74±2.74 mm on the right side and 21.92±3.33 mm on the left side, from the base of the ramus was 22.33±3.32 mm on the right side and 25.35±4.5 mm on the left side, from the third molar tooth was 22.84±3.94 mm on the right side and 23.23±4.21 mm on the left side, from the apex of retromolar trigone was 12.27±12.13 mm on the right side and 12.13±2.35 mm on the left side. Accessory mandibular foramen was present in 32.36% of mandibles. Knowledge of location mandibular foramen is useful to the maxillofacial surgeons, oncologists and radiologists.

Mandibular advancement appliance for obstructive sleep apnoea

DEFF Research Database (Denmark)

Petri, Niels; Svanholt, Palle; Solow, Beni

2008-01-01

The aim of this trial was to evaluate the efficacy of a mandibular advancement appliance (MAA) for obstructive sleep apnoea (OSA). Ninety-three patients with OSA and a mean apnoea-hypopnoea index (AHI) of 34.7 were centrally randomised into three, parallel groups: (a) MAA; (b) mandibular non...

Occlusal plane rotation: aesthetic enhancement in mandibular micrognathia.

Science.gov (United States)

Rosen, H M

1993-06-01

Patients afflicted with extreme degrees of mandibular micrognathia typically have vertically deficient rami as well as sagittally deficient mandibular bodies. This results in deficient posterior facial height, an obtuse gonial angle, excessively steep occlusal and mandibular planes, and a compensatory increase in anterior facial height. The entire maxillomandibular complex is overrotated in a clockwise direction. Standard orthognathic surgical correction fails to address this rotational deformity. As a consequence, the achieved projection of the lower face is inadequate, posterior facial height is further reduced, and occlusal and mandibular planes remain steep. Eleven patients with severe mandibular micrognathia underwent a surgical correction involving occlusal plane rotation to its normal orientation relative to Frankfort horizontal. This was accomplished by Le Fort I osteotomy to shorten the anterior maxilla (creating open bites in seven patients and making preexisting open bites worse in four patients) and sagittal split ramus osteotomies to advance and rotate the mandibular body counterclockwise, thus closing the surgically produced open bite. Counterclockwise rotation of the mandible afforded significantly greater sagittal displacement at the B point (mean 17 mm) than at the first molar (mean 10 mm) and produced adequate degrees of projection of the lower face when accompanied by a modest sliding genioplasty (mean 6.9 mm). Total advancement at the pogonion was a mean of 25.2 mm. In addition, posterior facial height was preserved, and mandibular and occlusal planes were normalized to mean angles of 27 and 10 degrees, respectively. At follow-up, which ranged from 9 to 24 months with a mean of 14.1 months, the mean sagittal relapse at the B point was 1.9 mm. Although heretofore considered unstable and therefore not clinically accepted, maxillomandibular counterclockwise rotation to normalize the occlusal plane rotational deformity provides stable, aesthetically

Sexual dimorphism of the internal mandibular chamber in Fayum Pliohyracidae (Mammalia)

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de Blieux, D.D.; Baumrind, M.R.; Simons, E.L.; Chatrath, P.S.; Meyer, G.E.; Attia, Y.S.

2006-01-01

An internal mandibular fenestra and chamber are found in many fossil hyracoids. The internal mandibular fenestra is located on the lingual surface of the mandibular corpus and opens into a chamber within the mandible. The mandibular chamber is maximally developed in late Eocene Thyrohyrax meyeri and early Oligocene Thyrohyrax domorictus from the Fayum Province of Egypt. The function of this chamber is unknown as it is not found in extant hyraxes, nor is it known to occur in any other mammal. In Thyrohyrax, this feature appears to be sexually dimorphic because it is confined to roughly one half of the specimens that otherwise cannot be separated by dental characteristics or measurements. It has been suggested that the chamber is found in females based on the presumed distribution of this character in other fossil hyracoids. Fossils from Fayum Quarry L-41, preserving the sexually dimorphic anterior dentition, show that, in Thyrohyrax meyeri and Thyrohyrax domorictus, the internal mandibular chamber is found in males. In Thyrohyrax litholagus, an internal mandibular fenestra and inflated mandibular chamber occurs in males whereas females show the variable presence of an internal mandibular fossa or fenestra but lack an expanded chamber. Other genera show differing patterns of sexual variation in which some Fayum hyracoids have an internal mandibular fenestra in both sexes but with the greatest development of the mandibular chamber occurring in males. We review functions proposed for the internal mandibular chamber and suggest that it housed a laryngeal air sac that may have had a vocal function by acting as a resonating chamber. ?? 2006 by the Society of Vertebrate Paleontology.

Mandibular Condyle Fractures and Treatment Modalities

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Halil ibrahim Kisa

2014-08-01

Full Text Available Maxillofacial injuries are most commonly associated with falls, motor and vehicle accidents, sports-related trauma, and interpersonel violence. The complexity of mandibular condyle region and its anatomic proximity to other craniofacial structures complicate diagnosis and treatment. Thus, treatment approaches of mandibular condyle fracture are still controversial. In the literature, different success rates are reported about observation versus treatment, closed reduction versus open reduction and fixation methods. In the present article, controversial issues related to mandibular condyle fractures were reviewed under the light of current literature. In conclusion, the simplest way that can be done with the least risk of complication should be chosen during treatment planning. In addition, current adjunctive treatment methods accelerating healing of fracture should be considered. [Archives Medical Review Journal 2014; 23(4.000: 658-671

A new technique for mandibular osteotomy

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Puricelli Edela

2007-03-01

Full Text Available Abstract Sagittal split osteotomy (SSO is a surgical technique largely employed for mandibular mobilizations in orthognatic procedures. However, the traditional design of buccal osteotomy, located at the junction of mandibular ramus and body, may prevent more extensive sliding between the bone segments, particularly on the advance, laterality and verticality of the mandibular body. The author proposes a new technical and conceptual solution, in which osteotomy is performed in a more distal region, next to the mental formamen. Technically, the area of contact between medullary-cancellous bone surfaces is increased, resulting in larger sliding rates among bone segments; it also facilitates the use of rigid fixation systems, with miniplates and monocortical screws. Conceptually, it interferes with the resistance arm of the mandible, seen as an interpotent lever of the third gender.

Abnormal perfusion on myocardial perfusion SPECT in patients with Wolff-Parkinson-White syndrome

International Nuclear Information System (INIS)

Kang, Do Young; Cha, Kwang Soo; Han, Seung Ho; Park, Tae Ho; Kim, Moo Hyun; Kim, Young Dae

2005-01-01

Abnormal myocardial perfusion may be caused by ventricular preexcitation, but its location, extent, severity and correlation with accessory pathway (AP) are not established. We evaluated perfusion patterns on myocardial perfusion SPECT and location of AP in patients with WPW (Wolff-Parkison-White) syndrome. Adenosine Tc-99m MIBI or Tl-201 myocardial perfusion SPECT was performed in 11 patients with WPW syndrome. Perfusion defects (PD) were compared to AP location based on ECT with Fitzpatrick's algorithm of electrophysiologic study and radiofrequency catheter ablation. Patients had atypical chest discomfort or no symptom. Risk of coronary artery disease (CAD) was below 0.1 in 11 patients using the nomogram to estimate the probability of CAD. Coronary angiography was performed in 4 patients(mid-LAD 50% in one, normal in others). In 4 patients, AP localization was done by electrophysiologic study and radiofrequency catheter ablation (RFCA). Small to large extent (11.0 ± 8.5%, range:3 ∼ 35%) and mild to moderate severity (-71 ± 42.7%, range:-217 ∼ -39%) of reversible (n=9) or fixed (n=1) perfusion defects were noted. One patients with right free wall (right lateral) AP showed normal. PD locations were variable following the location of AP. One patient with left lateral wall AP was followed 6 weeks after RFCA and showed significantly decreased PD on SPECT with successful ablation. Myocardial perfusion defect showed variable extent, severity and location in patients with WPW syndrome. Abnormal perfusion defect showed in most of all patients, but if did not seem to be correlated specifically with location of accessory pathway and coronary artery disease. Therefore myocardial perfusion SPECT should be interpreted carefully in patients with WPW syndrome

Abnormal perfusion on myocardial perfusion SPECT in patients with Wolff-Parkinson-White syndrome

Energy Technology Data Exchange (ETDEWEB)

Kang, Do Young; Cha, Kwang Soo; Han, Seung Ho; Park, Tae Ho; Kim, Moo Hyun; Kim, Young Dae [Donga University College of Medicine, Busan (Korea, Republic of)

2005-02-15

Abnormal myocardial perfusion may be caused by ventricular preexcitation, but its location, extent, severity and correlation with accessory pathway (AP) are not established. We evaluated perfusion patterns on myocardial perfusion SPECT and location of AP in patients with WPW (Wolff-Parkison-White) syndrome. Adenosine Tc-99m MIBI or Tl-201 myocardial perfusion SPECT was performed in 11 patients with WPW syndrome. Perfusion defects (PD) were compared to AP location based on ECT with Fitzpatrick's algorithm of electrophysiologic study and radiofrequency catheter ablation. Patients had atypical chest discomfort or no symptom. Risk of coronary artery disease (CAD) was below 0.1 in 11 patients using the nomogram to estimate the probability of CAD. Coronary angiography was performed in 4 patients(mid-LAD 50% in one, normal in others). In 4 patients, AP localization was done by electrophysiologic study and radiofrequency catheter ablation (RFCA). Small to large extent (11.0 {+-} 8.5%, range:3 {approx} 35%) and mild to moderate severity (-71 {+-} 42.7%, range:-217 {approx} -39%) of reversible (n=9) or fixed (n=1) perfusion defects were noted. One patients with right free wall (right lateral) AP showed normal. PD locations were variable following the location of AP. One patient with left lateral wall AP was followed 6 weeks after RFCA and showed significantly decreased PD on SPECT with successful ablation. Myocardial perfusion defect showed variable extent, severity and location in patients with WPW syndrome. Abnormal perfusion defect showed in most of all patients, but if did not seem to be correlated specifically with location of accessory pathway and coronary artery disease. Therefore myocardial perfusion SPECT should be interpreted carefully in patients with WPW syndrome.

Prostacyclin production in rabbit arteries in situ: inhibition by arachidonic acid-induced endothelial cell damage or by low-dose aspirin.

Science.gov (United States)

Ingerman-Wojenski, C; Silver, M J; Smith, J B; Nissenbaum, M; Sedar, A W

1981-04-01

The central artery of the rabbit ear was perfused in situ and effluent fractions from the artery were assayed for 6-keto-prostaglandin F1 alpha (6-K-PGF1 alpha) and thromboxane B2 (TxB2), the stable metabolites of prostacyclin (PGI2) and TxA2, using specific radioimmunoassays. These metabolites of arachidonic acid (AA) were not detected in the effluent during infusion of Tyrode's solution but both metabolites were detected when small amounts of AA were infused into the artery. Examination of the arteries by scanning electron microscopy revealed that high concentrations of AA which caused a short burst of 6-K-PGF1 alpha and TxB2 production damaged the endothelial cells while lower concentrations which stimulated continuous production did not cause damage. When a non-damaging concentration of AA was infused into an artery that had previously received a damaging concentration, PG production was greatly reduced. Pretreatment of the rabbits with 4 mg/kg acetyl-salicylic acid (ASA) inhibited 6-K-PGF1 alpha production by the rabbit ear artery in response to AA and 70% inhibition was still evident 18 hours after ASA.

Pulmonary artery perfusion versus no pulmonary perfusion during cardiopulmonary bypass in patients with COPD

DEFF Research Database (Denmark)

Buggeskov, Katrine B; Sundskard, Martin M; Jonassen, Thomas

2016-01-01

INTRODUCTION: Absence of pulmonary perfusion during cardiopulmonary bypass (CPB) may be associated with reduced postoperative oxygenation. Effects of active pulmonary artery perfusion were explored in patients with chronic obstructive pulmonary disease (COPD) undergoing cardiac surgery. METHODS: 90...... perfusion with normothermic oxygenated blood during cardiopulmonary bypass appears to improve postoperative oxygenation in patients with COPD undergoing cardiac surgery. Pulmonary artery perfusion with hypothermic HTK solution does not seem to improve postoperative oxygenation. TRIAL REGISTRATION NUMBER...

Maxillary-driven simultaneous maxillo-mandibular distraction for hemifacial microsomia.

Science.gov (United States)

Nakajima, Hideo; Sakamoto, Yoshiaki; Tamada, Ikkei; Ogata, Hisao; Kishi, Kazuo; Sakamoto, Teruo

2011-12-01

We treat hemifacial microsomia with a combination of surgery and orthodontic treatment during the growth period, resulting in early improvement in facial asymmetry and the induction of normal growth. We previously used gradual distraction of the mandibular ramus for Pruzansky's type II classification (Pruzansky, 1969). In type II cases, the maxilla should also be treated actively as, using this technique, improvement of the occlusal plane is difficult to achieve, resulting in a cross bite and difficulties in post-operative orthodontic treatment-especially in older patients. Morphologically, the mandibular angle region of the operative side is flat, and the angle of the mouth remains elevated. We performed mandibular-driven simultaneous maxillo-mandibular distraction while the occlusion was maintained using intermaxillary anchorage. However, mandibular-driven distraction tended to elongate the face because the mandible only elongated downwards and the mandibular ramus did not reach the glenoid. Furthermore, external distraction devices produce significant distress for patients until removal of the device and cause scars on the face. We developed a new internal distraction device with a variable angle and performed maxillary-driven simultaneous maxillo-mandibular distraction using this device. The result was morphologically satisfactory and solved the above problems. Because the patient was in the growth period, careful follow-up and induction to normal growth were important while the inferior growth of the affected side was monitored. Copyright © 2010 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

Radiologic study of mandibular third molar of Korean youths

International Nuclear Information System (INIS)

Ahn, Hyung Kyu

1982-01-01

The author has made a study on the classification of the mandibular 3rd molars of Korean youths through dental radiography by means of Pell and Gregory's classification and on the prevalence of the dental caries of distal surface of the mandibular 2nd molar adjacent to the mandibular 3rd molars turned anteriorly. The results are as follow; 1. It was found that the largest case number was class I (272 cases, 52.9%) in the relation of the tooth to the ramus of the mandible and 2nd molar. 2. The mesio-angular position was the largest number (239 cases, 46.5%) in the relation of the long axis of the impacted mandibular 3rd molar to the long axis of the 2nd molar. 3. The mesio-angular position of class I was the largest number (140 cases, 27.2%) in the relation of the tooth to the ramus of the mandible and 2nd molar and the long axis of the impacted mandibular 3rd moral to the long axis of the 2nd molar. 4. The average angle of the long axis of mandibular 3rd molar in mesioangular position or horizontal position to the occlusal plane was 143 W 5. Mandibular 3rd molar with lesion such as dental cries or pericoronitis was 73 cases (14.2). 6. The caries incidence rate of the distal surface of the 2nd molar was about 3.1%.

Relative permeability of the endothelium and epithelium of rabbit lungs

International Nuclear Information System (INIS)

Effros, R.M.; Mason, G.R.; Silverman, P.; Hukkanen, J.

1986-01-01

Electron micrographic studies of lungs suggest that the epithelial cells are more tightly joined than the underlying endothelium, and macromolecules penetrate the endothelium more readily than the epithelium. Comparisons of epithelial and endothelial permeability to small molecules have been based upon the relative rates at which solutes traverse the alveolar-capillary barrier in fluid filled lungs and those at which they equilibrate across the capillaries in air-filled lungs. Because the former process is much slower than the latter, it has been concluded that the epithelium is less permeable to small solutes than the endothelium. However this difference may be related to inadequate access of solutes to airway surfaces. In this study, solute losses from the vascular space were compared to those from the airspace in perfused, fluid-filled rabbit lungs. 36 Cl - and 125 I - were lost from air-spaces almost twice as rapidly as 22 Na + . In contrast, the endothelium is equally permeable to 22 Na + and these anions. Loss of 3 H-mannitol from the perfusate resembled that of 22 Na + for about 30 minutes, after which diffusion of 3 H-mannitol into the tissue nearly ceased. These observations suggest that the epithelium is more permselective than the endothelium. By resisting solute and water transport, the epithelium tends to prevent alveolar flooding and confines edema to the interstitium, where it is less likely to interfere with gas exchange

Reverse ventilation--perfusion mismatch

International Nuclear Information System (INIS)

Palmaz, J.C.; Barnett, C.A.; Reich, S.B.; Krumpe, P.E.; Farrer, P.A.

1984-01-01

Patients having lobar airway obstruction or consolidation usually have decreases of both ventilation and perfusion on lung scans. We report three patients in whom hypoxic vasoconstriction was apparently incomplete, resulting in a ''reversed'' ventilation-perfusion mismatch. Perfusion of the hypoxic lobe on the radionuclide scan was associated with metabolic alkalosis, pulmonary venous and pulmonary arterial hypertension in these patients

Osteochondroma involving mandibular condyle

Directory of Open Access Journals (Sweden)

Latika Bachani

2017-01-01

Full Text Available Osteochondroma is defined as an osteocartilagenous exostosis with cartilage capped exophytic lesion that arises from the bone cortex. It is a slow growing benign tumor that is rarely seen in the maxillofacial region. Osteochondroma of the mandibular condyle is a relatively rare condition that causes a progressive enlargement of the condyle, usually resulting in facial asymmetry, temporomandibular joint (TMJ dysfunction and malocclusion. Radiographically, there is a unilaterally enlarged condyle usually with an exophytic growth of the tumor from the condylar head. The treatment of osteochondroma is primarily surgical resection of the tumor. This paper reports a case of osteochondroma of the right mandibular condyle presenting as a painless restricted mouth opening.

Mandibular kinematics after orthognathic surgical treatment a pilot study.

Science.gov (United States)

Sforza, Chiarella; Ugolini, Alessandro; Rocchetta, Davide; Galante, Domenico; Mapelli, Andrea; Giannì, Aldo Bruno

2010-03-01

We recorded three-dimensional mandibular movements, while the mouth was being opened and closed, using an optoelectronic motion analyser in 14 patients (5 skeletal Class II, 9 skeletal Class III) who were being assessed 7-49 months after orthognathic operations, and in 44 healthy subjects. All 14 patients had satisfactory healing on clinical examination, and function had been restored. Mandibular movement was divided into its rotational and translational components. On maximum mouth opening, the patients had significantly less total displacement of the mandibular interincisor point (p=0.05), and more mandibular movement that was explained by pure condylar rotation (p=0.006), than control subjects. There was no significant relation between maximum mouth opening and percentage rotation. While mandibular motion was well restored clinically by orthognathic surgery, the kinematics of the joint were modified. Larger studies and longitudinal investigations are necessary to appreciate the clinical relevance of the variations in condylar rotational and translational components.

Fixation of zygomatic and mandibular fractures with biodegradable plates

OpenAIRE

Degala, Saikrishna; Shetty, Sujeeth; Ramya, S

2013-01-01

Context: In this prospective study, 13 randomly selected patients underwent treatment for zygomatic?complex fractures (2 site fractures) and mandibular fractures using 1.5 / 2 / 2.5-mm INION CPS biodegradable plates and screws. Aims: To assess the fixation of zygomatic-complex and mandibular fractures with biodegradable copolymer osteosynthesis system. Materials and Methods: In randomly selected 13 patients, zygomatic-complex and mandibular fractures were plated using resorbable plates and sc...

Autologous bone-marrow mesenchymal stem cell implantation and endothelial function in a rabbit ischemic limb model.

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Shinsuke Mikami

Full Text Available BACKGROUND: The purpose of this study was to determine whether autologous mesenchymal stem cells (MSCs implantation improves endothelial dysfunction in a rabbit ischemic limb model. METHODS: We evaluated the effect of MSC implantation on limb blood flow (LBF responses to acetylcholine (ACh, an endothelium-dependent vasodilator, and sodium nitroprusside (SNP, an endothelium-independent vasodilator, in rabbits with limb ischemia in which cultured MSCs were implanted (n = 20 or saline was injected as a control group (n = 20. LBF was measured using an electromagnetic flowmeter. A total of 10(6 MSCs were implanted into each ischemic limb. RESULTS: Histological sections of ischemic muscle showed that capillary index (capillary/muscle fiber was greater in the MSC implantation group than in the control group. Laser Doppler blood perfusion index was significantly increased in the MSC implantation group compared with that in the control group. LBF response to ACh was greater in the MSC group than in the control group. After administration of N(G-nitro-L-arginine, a nitric oxide synthase inhibitor, LBF response to ACh was similar in the MSC implantation group and control group. Vasodilatory effects of SNP in the two groups were similar. CONCLUSIONS: These findings suggest that MSC implantation induces angiogenesis and augments endothelium-dependent vasodilation in a rabbit ischemic model through an increase in nitric oxide production.

Algorithm of imaging modalities in cases of mandibular fractures

International Nuclear Information System (INIS)

Mihailova, H.

2009-01-01

Mandibular fracture is the most common bone fracture of maxillo-facial trauma. Up to now the main method for examination of the mandible is radiography. The aim of the issue is to present an algorithm of imaging modalities for investigation of patients in cases of mandibular trauma. It consists of series of X ray techniques and views of the facial skull named mandibulo-facial. This standardizes mandibulo-facial series includes exactly determined four projections done by conventional X ray techniques: posterior-anterior view of skull (PA or AP), oblique view of the left mandible; oblique view of the right mandible; occipito-mental view. Using these four planned radiograms is obligatory for each mandibular trauma. Panoramic X-ray is obligatory in cases of apparatus availability; this abolish only oblique views (left and right). Occipito-mental view of the skull gives anatomically better the coronoid process of the mandible, the zygoma complex, the orbital edges and maxillar sinus than Waters projection. So mandibulo-facial series of four planned radiograms is not only for diagnostic of mandibular fractures, but as a screening of mandibulo-facial trauma too. Thus using algorithm of imaging modalities in cases of mandibular fracture leads to optimization of diagnostic process in patients with mandibular trauma. (author)

Perfusion dyssynchrony analysis

NARCIS (Netherlands)

Chiribiri, A.; Villa, A.D.M.; Sammut, E.; Breeuwer, M.; Nagel, E.

2015-01-01

AIMS: We sought to describe perfusion dyssynchrony analysis specifically to exploit the high temporal resolution of stress perfusion CMR. This novel approach detects differences in the temporal distribution of the wash-in of contrast agent across the left ventricular wall. METHODS AND RESULTS:

Chincup treatment modifies the mandibular shape in children with prognathism.

Science.gov (United States)

Alarcón, José Antonio; Bastir, Markus; Rosas, Antonio; Molero, Julia

2011-07-01

Although chincups are the preferred treatment for growing children with mandibular prognathism, the mechanism by which chincups improve this condition remains unclear. The aim of this study was to use geometric morphometrics to evaluate changes in the shape of the mandible of prognathic children treated with a chincup. Geometric morphometrics were used to evaluate the short-term mandibular shape changes in 50 prognathic children treated with chincups compared with 40 untreated matched controls. Twenty-one 2-dimensional mandibular landmarks from cephalograms taken before and after 36 months of treatment or observation were analyzed by Procrustes superimposition and thin plate spline. Permutation tests of the treated patients showed highly significant differences in the mandibular shapes before and after treatment, and compared with the control group after the observation period. The thin plate spline grid deformations indicated more rectangular mandibular configuration, forward condyle orientation, condyle neck compression, gonial area compression, and symphysis narrowing. Early chincup treatment widely modifies the mandibular shape of prognathic children to improve Class III malocclusion. Copyright © 2011 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

Augmented mandibular bone structurally adapts to functional loading

NARCIS (Netherlands)

Verhoeven, J. W.; Ruijter, J. M.; Koole, R.; de Putter, C.; Terlou, M.; Cune, M. S.

2013-01-01

Long-term changes in trabecular bone structure during the 10 years following onlay grafting with simultaneous mandibular implant placement were studied. Extraoral radiographs of both mandibular sides in eight patients were taken regularly. Bone structure was analysed using a custom-written image

Brain perfusion: computed tomography applications

International Nuclear Information System (INIS)

Miles, K.A.

2004-01-01

Within recent years, the broad introduction of fast multi-detector computed tomography (CT) systems and the availability of commercial software for perfusion analysis have made cerebral perfusion imaging with CT a practical technique for the clinical environment. The technique is widely available at low cost, accurate and easy to perform. Perfusion CT is particularly applicable to those clinical circumstances where patients already undergo CT for other reasons, including stroke, head injury, subarachnoid haemorrhage and radiotherapy planning. Future technical developments in multi-slice CT systems may diminish the current limitations of limited spatial coverage and radiation burden. CT perfusion imaging on combined PET-CT systems offers new opportunities to improve the evaluation of patients with cerebral ischaemia or tumours by demonstrating the relationship between cerebral blood flow and metabolism. Yet CT is often not perceived as a technique for imaging cerebral perfusion. This article reviews the use of CT for imaging cerebral perfusion, highlighting its advantages and disadvantages and draws comparisons between perfusion CT and magnetic resonance imaging. (orig.)

Diagnostic ability of panoramic radiography for mandibular fractures

International Nuclear Information System (INIS)

Lee, Ji Hyun; Jung, Yun Hoa; Cho Bong Hae; Hwang, Dae Seok

2010-01-01

The purpose of this study was to evaluate the diagnostic efficacy of panoramic radiographs for detection of mandibular fractures. The sample was comprised of 65 patients (55 fractured, 10 non-fractured) with 92 fracture sites confirmed by multi-detector computed tomography (CT). Panoramic radiographs were evaluated for mandibular fractures by six examiners; two oral and maxillofacial radiologists (observer A and B), two oral and maxillofacial surgeons (observer C and D), and two general dentists (observer E and F). Sensitivity of panoramic radiography for mandibular fractures was 95.7% in observer A and B, 93.5% in observer C and D and 80.4% in observer E and F. The lowest sensitivity was shown in symphyseal/parasymphyseal areas, followed by subcondylar/condylar regions. Panoramic radiography is adequate for detection of mandibular fractures. However, additional multidetector CT is recommended to ascertain some indecisive fractures of symphysis and condyle, and in complicated fractures.

Diagnostic ability of panoramic radiography for mandibular fractures

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Lee, Ji Hyun; Jung, Yun Hoa; Cho Bong Hae; Hwang, Dae Seok [School of Dentistry, Pusan National University, Pusan (Korea, Republic of)

2010-03-15

The purpose of this study was to evaluate the diagnostic efficacy of panoramic radiographs for detection of mandibular fractures. The sample was comprised of 65 patients (55 fractured, 10 non-fractured) with 92 fracture sites confirmed by multi-detector computed tomography (CT). Panoramic radiographs were evaluated for mandibular fractures by six examiners; two oral and maxillofacial radiologists (observer A and B), two oral and maxillofacial surgeons (observer C and D), and two general dentists (observer E and F). Sensitivity of panoramic radiography for mandibular fractures was 95.7% in observer A and B, 93.5% in observer C and D and 80.4% in observer E and F. The lowest sensitivity was shown in symphyseal/parasymphyseal areas, followed by subcondylar/condylar regions. Panoramic radiography is adequate for detection of mandibular fractures. However, additional multidetector CT is recommended to ascertain some indecisive fractures of symphysis and condyle, and in complicated fractures.

Autotransplantation of Mandibular Third Molar: A Case Report

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Pabbati Ravi kumar

2012-01-01

Full Text Available Autogenous transplantation is a feasible, fast, and economical option for the treatment of nonsalvageable teeth when a suitable donor tooth is available. This paper presents successful autotransplantation of a mature mandibular left third molar (38 without anatomical variances is used to replace a mandibular left second molar (37. The mandibular second molar was nonrestorable due to extensive root caries and resorption of distal root. After extraction of mandibular second and third molars, root canal therapy was done for the third molar extraorally, and the tooth was reimplanted into the extracted socket of second molar site. After one year, clinical and radiographic examination revealed satisfactory outcome with no signs or symptoms suggestive of pathology. In selected cases, autogenous tooth transplantation, even after complete root formation of the donor tooth, may be considered as a practical treatment alternative to conventional prosthetic rehabilitation or implant treatment.

Eosinophilic granuloma of the mandibular condyle

International Nuclear Information System (INIS)

Huh, Kyung Hoe; Yi, Won Jin; Oh, Sung Won; Lee, Sam Sun; Choi, Mun Kyung

2008-01-01

The present study reports a case of eosinophilic granuloma of the mandibular condyle. Eosinophilic granulomas on the mandibular condyle are very rare, but there are several common clinical and radiographic presentations. The clinical presentations involve swelling on preauricular area, limitation of opening, TMJ pain, etc. The radiographic presentations involve radiolucent lytic condylar lesion with or without pathologic fracture. Sometimes new bone formations are observed. The purpose of the article is to add new cases to the literatures.

Eosinophilic granuloma of the mandibular condyle

Energy Technology Data Exchange (ETDEWEB)

Huh, Kyung Hoe; Yi, Won Jin; Oh, Sung Won; Lee, Sam Sun [Department of Oral and Maxillofacial Radiology, and Dental Research Institute, School of Dentistry, Seoul National University, Seoul (Korea, Republic of); Choi, Mun Kyung [Department of Oral and Maxillofacial Surgery, College of Medicine, Inje University Sanggye Paik Hospital, Seoul (Korea, Republic of)

2008-03-15

The present study reports a case of eosinophilic granuloma of the mandibular condyle. Eosinophilic granulomas on the mandibular condyle are very rare, but there are several common clinical and radiographic presentations. The clinical presentations involve swelling on preauricular area, limitation of opening, TMJ pain, etc. The radiographic presentations involve radiolucent lytic condylar lesion with or without pathologic fracture. Sometimes new bone formations are observed. The purpose of the article is to add new cases to the literatures.

Mandibular fracture cases in Pelotas, Rio Grande do Sul, Brazil

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Rafael Silva da Silva

2009-10-01

Full Text Available Objectives: To analyze the data in the literature, which show a high incidence of mandibular fractures. The aim of this research was to elucidate the context in which these fractures occur among patients attended at the first aid center of “Pronto Socorro Municipal de Pelotas”, Rio Grande do Sul, Brazil. Methods: From the records referring to the period of June, 2001 to August, 2007, there were 1 345 patients with facial fractures. Of this total, 116 patients with mandibular fracture were selected for this study and the items analysed were: age, gender, mandibular fracture site, etiology and period of the year. Results: It was found that 86.2% of the sample were men. The most prevalent age was 20 to 29 years old representing 36.2%, and the most affected mandibular sites were the body, with 29 cases (25%, and the condyle, with 26 cases (22.4%. The most common cause of fractures was the physical aggression representing 37.1%. The period of the year with the highest incidence of mandibular fractures was the summer, with 38 cases (32.8%. Conclusion: It was therefore observed that the patients with mandibular fracture assisted at Pronto-Socorro Municipal de Pelotas, Rio Grande do Sul, Brazil, were generally men, 20 to 29 years old with mandibular body fracture and they were victims of physical aggression.

Early Loaded Single Implant Reinforced Mandibular Overdenture

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K. Nischal

2016-01-01

Full Text Available Rehabilitating atrophied mandible with two-implant supported denture is a common treatment modality for implant retained removable overdenture in mandible. This paper aims to design a treatment modality where single implant reinforced overdenture is fabricated for a severely atrophied mandibular ridge with early loading protocol. Results of studies have shown that a single implant mandibular overdenture significantly increases the satisfaction and quality of life of patients with edentulism. Midline fracture of the prosthesis is the most common complication related to single implant and two-implant retained mandibular overdentures. To manage such complication, a thin metal mesh is used to reinforce the overdenture and also to make the prostheses lighter and cost effective as compared to conventional cast metal framework.

Intraoperative monitoring of marginal mandibular nerve during neck dissection.

Science.gov (United States)

Tirelli, Giancarlo; Bergamini, Pier Riccardo; Scardoni, Alessandro; Gatto, Annalisa; Boscolo Nata, Francesca; Marcuzzo, Alberto Vito

2018-05-01

The purpose of this study was to assess the efficacy of intraoperative nerve integrity monitoring (NIM) to prevent marginal mandibular nerve injuries during neck dissection. This prospective study compared 36 patients undergoing NIM-assisted neck dissection from July 2014 to March 2015 to a cohort of 35 patients subjected to neck dissection over an identical period of time before the technique was introduced. We also assessed possible correlations between marginal mandibular nerve injuries and other factors, such as anthropometric measurements, presence of clinical neck metastases, type of neck dissection, and site of primary tumor. The incidence of marginal mandibular nerve paralyses was significantly lower among the group of patients undergoing NIM-assisted neck dissection (P = .021). There was no significant difference in the duration of the procedure, and the technique resulted in a limited increase of cost. No other factor seemed to influence the onset of marginal mandibular nerve palsy. In our opinion, NIM is a valuable aid for preventing marginal mandibular nerve injuries during neck dissection. © 2018 Wiley Periodicals, Inc.

A capillary-based perfusion phantom for simulation of brain perfusion for MRI

International Nuclear Information System (INIS)

Maciak, A.; Kronfeld, A.; Mueller-Forell, W.; Wille, C.; Kempski, O.; Stoeter, P.

2010-01-01

Purpose: The measurement of the CBF is a non-standardized procedure and there are no reliable gold standards. This abstract shows a capillary-based perfusion-phantom for CE-DSC-MRI. It has equivalent flow properties to those within the tissue capillary system of the human brain and allows the validation of the Siemens Perfusion (MR) software. Materials and Methods: The perfusion phantom consists of a dialyzer for the simulation of the capillary system, a feeding tube for simulation of the AIF and a pulsatile pump for simulation of the heart. Using this perfusion phantom, the exact determination of the gold standard CBF due to the well-known geometry of the phantom is easy. It was validated based on different perfusion measurements. These measurements were investigated with standard software (Siemens Perfusion MR). The software determined the CBF within the capillary system. Based on this CBF, a comparison to the gold standard was made with several different flow speeds. After AIF selection, a total of 726 CBF data points were automatically extracted by the software. Results: This results in a comparison of the gold standard CBF to these 726 CBF values. Therefore, a reproducible and reliable deviation estimation between gold standard CBF and measured CBF using the software was computed. It can be shown that the deviation between gold standard and software-based evaluation ranges between 1 and 31 %. Conclusion: There is no significance for any correlation between flow speed and amount of deviation. The mean measured CBF is 11.4 % higher than the gold standard CBF (p-value < 0.001). Using this kind of perfusion-phantom, the validation of different software systems allows reliable conclusions about their quality. (orig.)

Perfusion CT in acute stroke

International Nuclear Information System (INIS)

Eckert, Bernd; Roether, Joachim; Fiehler, Jens; Thomalla, Goetz

2015-01-01

Modern multislice CT scanners enable multimodal protocols including non-enhanced CT, CT angiography, and CT perfusion. A 64-slice CT scanner provides 4-cm coverage. To cover the whole brain, a 128 - 256-slice scanner is needed. The use of perfusion CT requires an optimized scan protocol in order to reduce exposure to radiation. As compared to non-enhanced CT and CT angiography, the use of CT perfusion increases detection rates of cerebral ischemia, especially small cortical ischemic lesions, while the detection of lacunar and infratentorial stroke lesions remains limited. Perfusion CT enables estimation of collateral flow in acute occlusion of large intra- or extracranial arteries. Currently, no established reliable thresholds are available for determining infarct core and penumbral tissue by CT perfusion. Moreover, perfusion parameters depend on the processing algorithms and the software used for calculation. However, a number of studies point towards a reduction of cerebral blood volume (CBV) below 2 ml/100 g as a critical threshold that identifies infarct core. Large CBV lesions are associated with poor outcome even in the context of recanalization. The extent of early ischemic signs on non-enhanced CT remains the main parameter from CT imaging to guide acute reperfusion treatment. Nevertheless, perfusion CT increases diagnostic and therapeutic certainty in the acute setting. Similar to stroke MRI, perfusion CT enables the identification of tissue at risk of infarction by the mismatch between infarct core and the larger area of critical hypoperfusion. Further insights into the validity of perfusion parameters are expected from ongoing trials of mechanical thrombectomy in stroke.

Radiographic Localization of the Mental Foramen and Mandibular Canal

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Farzaneh Afkhami

2013-01-01

Full Text Available Objective: Accurately localizing the mental foramen and mandibular canal is important when administering local anesthesia and performing surgery; therefore, knowing the normal range of the possible locations is essential. Our purpose was to assess the location of the mental foramen and mandibular canal in an Iranian population using panoramic radiography.Materials and Methods: Standard panoramic radiographies were performed. The positions of 100 mental foramens were evaluated. The distances from the center of the mental foramen to the superior and inferior borders of the mandible and to the apexes of the first and second premolar were measured. The distance of the mental foramens from the mandibular midline and the diameter of the mandibular canal in the mental foramen connection were also measured.Results: Among 100 mental foramens, 6% were positioned under the first premolar, 24% were between the first and second premolars, 67% were under the second premolar, and the remaining 3% were behind the second premolar. The mean distance from the mental foramen to the mandibular midline was 27.77±3.20 mm. The mean diameter of the mandibular canal in the mental foramen connection was 3.09±0.69mm.Conclusion: The mental foramen was near the second premolar and the inferior border of the mandible. This information can be used to perform safer mental nerve blocks in surgical interventions.

21 CFR 874.3695 - Mandibular implant facial prosthesis.

Science.gov (United States)

2010-04-01

... made of materials such as stainless steel, tantalum, titanium, cobalt-chromium based alloy... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Mandibular implant facial prosthesis. 874.3695... (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Prosthetic Devices § 874.3695 Mandibular implant...

Flow heterogeneity following global no-flow ischemia in isolated rabbit heart

International Nuclear Information System (INIS)

Marshall, Robert C.; Powers-Risius, Patricia; Reutter, Bryan W.; Schustz, Amy M.; Kuo, Chaincy; Huesman, Michelle K.; Huesman, Ronald H.

2002-01-01

The purpose of this study was to evaluate flow heterogeneity and impaired reflow during reperfusion following 60 min global no-flow ischemia in the isolated rabbit heart. Radiolabeled microspheres were used to measure relative flow in small left ventricular (LV) segments in five ischemia + reperfused hearts and in five non-ischemic controls. Although variable in the post-ischemic hearts, flow heterogeneity was increased relative to pre-ischemia for the whole LV (0.92 plus or minus 0.41 vs. 0.37 plus or minus 0.07, P < 0.05) as well as the subendocardium (Endo) and subepicardium (Epi) considered separately (endo: 1.28 plus or minus 0.74 vs. 0.30 plus or minus 0.09; epi: 0.69 plus or minus 0.22 vs. 0.38 plus or minus 0.08; P < 0.05 for both comparisons) during early reperfusion. There were also segments with abnormally reduced reflow. The number of segments with abnormally reduced reflow increased as flow heterogeneity increased. Abnormally reduced reflow indicates that regional ischemia can persist despite restoration of normal global flow. In addition, the relationship between regional and global flow is altered and venous outflow is derived from regions with continued perfusion and not the whole LV. These observations emphasize the need to quantify regional reflow during reperfusion following sustained no-flow ischemia in the isolated rabbit heart

Flow heterogeneity following global no-flow ischemia in isolated rabbit heart

Energy Technology Data Exchange (ETDEWEB)

Marshall, Robert C.; Powers-Risius, Patricia; Reutter, Bryan W.; Schustz, Amy M.; Kuo, Chaincy; Huesman, Michelle K.; Huesman, Ronald H.

2003-02-01

The purpose of this study was to evaluate flow heterogeneity and impaired reflow during reperfusion following 60 min global no-flow ischemia in the isolated rabbit heart. Radiolabeled microspheres were used to measure relative flow in small left ventricular (LV) segments in five ischemia + reperfused hearts and in five non-ischemic controls. Although variable in the post-ischemic hearts, flow heterogeneity was increased relative to pre-ischemia for the whole LV (0.92 plus or minus 0.41 vs. 0.37 plus or minus 0.07, P < 0.05) as well as the subendocardium (Endo) and subepicardium (Epi) considered separately (endo: 1.28 plus or minus 0.74 vs. 0.30 plus or minus 0.09; epi: 0.69 plus or minus 0.22 vs. 0.38 plus or minus 0.08; P < 0.05 for both comparisons) during early reperfusion. There were also segments with abnormally reduced reflow. The number of segments with abnormally reduced reflow increased as flow heterogeneity increased. Abnormally reduced reflow indicates that regional ischemia can persist despite restoration of normal global flow. In addition, the relationship between regional and global flow is altered and venous outflow is derived from regions with continued perfusion and not the whole LV. These observations emphasize the need to quantify regional reflow during reperfusion following sustained no-flow ischemia in the isolated rabbit heart.

Penetration of flomoxef into human maxillary and mandibular bones.

Science.gov (United States)

Igawa, H H; Sugihara, T; Yoshida, T; Kawashima, K; Ohura, T

1995-09-01

Penetration of flomoxef into the maxillary and mandibular bones was assayed clinically to provide data about its usefulness for the prevention of postoperative infection after maxillofacial surgery. Twenty-one patients undergoing maxillofacial surgery at our department were given flomoxef 2 g dissolved in 20 ml of physiological saline intravenously over 3 minutes during operation, and the serum, maxillary and mandibular concentrations were measured 1, 3, and 6 hours after injection by the band culture method using Escherichia coli 7437 as the indicator strain. The mean concentrations were 53.4, 16.1, and 2.6 micrograms/ml, respectively, in the serum, 17.6, 7.8, and 1.0 micrograms/g in maxillary bone, and 16.4, 4.2, and 0.9 micrograms/g in mandibular bone. The mean bone:serum ratios at 1, 3, and 6 hours were 33.0%, 48.2%, and 36.8%, respectively, for maxillary bone, and 30.7%, 26.2%, and 35.7% for mandibular bone. When compared with previously reported data on the bone:serum ratios in jaw of various other intravenous antibiotics, our results show that penetration of flomoxef into maxillary and mandibular bone is extremely high. As all the intramaxillary and intramandibular concentrations exceed its MIC80 values against clinical isolates of bacteria frequently isolated in cases of infection in the oral and maxillofacial region, it is apparent that one intravenous shot of flomoxef 2 g allows penetration of the drug into the maxillary and mandibular bones at effective concentrations. Flomoxef is therefore potentially useful for the prevention and treatment of infections in the oral and maxillofacial region, as it has excellent penetration into the maxillary and mandibular bones.

Volume perfusion CT imaging of cerebral vasospasm: diagnostic performance of different perfusion maps

Energy Technology Data Exchange (ETDEWEB)

Othman, Ahmed E. [RWTH Aachen University, Department of Diagnostic and Interventional Neuroradiology, Aachen (Germany); Eberhard Karls University Tuebingen, University Hospital Tuebingen, Department for Diagnostic and Interventional Radiology, Tuebingen (Germany); Afat, Saif; Nikoubashman, Omid; Mueller, Marguerite; Wiesmann, Martin; Brockmann, Carolin [RWTH Aachen University, Department of Diagnostic and Interventional Neuroradiology, Aachen (Germany); Schubert, Gerrit Alexander [RWTH Aachen University, Department of Neurosurgery, Aachen (Germany); Bier, Georg [Eberhard Karls University Tuebingen, University Hospital Tuebingen, Department for Diagnostic and Interventional Neuroradiology, Tuebingen (Germany); Brockmann, Marc A. [RWTH Aachen University, Department of Diagnostic and Interventional Neuroradiology, Aachen (Germany); University Hospital Mainz, Department of Neuroradiology, Mainz (Germany)

2016-08-15

In this study, we aimed to evaluate the diagnostic performance of different volume perfusion CT (VPCT) maps regarding the detection of cerebral vasospasm compared to angiographic findings. Forty-one datasets of 26 patients (57.5 ± 10.8 years, 18 F) with subarachnoid hemorrhage and suspected cerebral vasospasm, who underwent VPCT and angiography within 6 h, were included. Two neuroradiologists independently evaluated the presence and severity of vasospasm on perfusion maps on a 3-point Likert scale (0 - no vasospasm, 1 - vasospasm affecting <50 %, 2 - vasospasm affecting >50 % of vascular territory). A third neuroradiologist independently assessed angiography for the presence and severity of vasospasm on a 3-point Likert scale (0 - no vasospasm, 1 - vasospasm affecting < 50 %, 2 - vasospasm affecting > 50 % of vessel diameter). Perfusion maps of cerebral blood volume (CBV), cerebral blood flow (CBF), mean transit time (MTT), and time to drain (TTD) were evaluated regarding diagnostic accuracy for cerebral vasospasm with angiography as reference standard. Correlation analysis of vasospasm severity on perfusion maps and angiographic images was performed. Furthermore, inter-reader agreement was assessed regarding findings on perfusion maps. Diagnostic accuracy for TTD and MTT was significantly higher than for all other perfusion maps (TTD, AUC = 0.832; MTT, AUC = 0.791; p < 0.001). TTD revealed higher sensitivity than MTT (p = 0.007). The severity of vasospasm on TTD maps showed significantly higher correlation levels with angiography than all other perfusion maps (p ≤ 0.048). Inter-reader agreement was (almost) perfect for all perfusion maps (kappa ≥ 0.927). The results of this study indicate that TTD maps have the highest sensitivity for the detection of cerebral vasospasm and highest correlation with angiography regarding the severity of vasospasm. (orig.)

Localization of 14C-labeled 2% lidocaine hydrochloride after intraosseous anesthesia in the rabbit.

Science.gov (United States)

Goto, Takashi; Mamiya, Hideki; Ichinohe, Tatsuya; Kaneko, Yuzuru

2011-10-01

The purpose of this study was to investigate the tissue distribution of lidocaine hydrochloride in mandibular bone marrow after intraosseous anesthesia (IOA) in rabbits. We used macroautoradiography to examine the tissue distribution of a (14)C-labeled 2% lidocaine hydrochloride solution containing 1:80,000 epinephrine ((14)C-lidocaine). Under general anesthesia, (14)C-lidocaine was injected intraosseously or paraperiosteally. After IOA, animals were divided into three groups and observed at 1 (IOA-1), 5 (IOA-5), and 10 minutes (IOA-10) after injection. After infiltration anesthesia (IA), animals were observed at 1 minute after injection. The accumulation of (14)C-lidocaine was observed around the injection site in both the IA and the IOA groups. Paraperiosteally injected (14)C-lidocaine diffused to the surrounding tissues such as the lip, whereas IOA showed concentrated accumulation around the root apex throughout the experiment. The distribution area was significantly smaller in the IOA-1 group than in the IA group. The distribution area in the IOA-5 group was larger than those in the IOA-1 and IOA-10 groups. The accumulation of (14)C-lidocaine injected by IOA in rabbits was concentrated around the root apex. These results may explain the rapid onset time of IOA. Copyright © 2011 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Intermaxillary Fixation Screw Morbidity in Treatment of Mandibular Fractures

DEFF Research Database (Denmark)

Florescu, Vlad-Andrei; Kofod, Thomas; Pinholt, Else Marie

2016-01-01

Purpose The aim of the present retrospective study was to investigate the morbidity of screws used for intermaxillary fixation (IMF) in the treatment of mandibular fractures. A review of the published data was also performed for a comparison of outcomes. Our hypothesis was that the use of screws...... for IMF of mandibular fractures would result in minimal morbidity. Materials and Methods Patients treated for mandibular fractures from 2007 to 2013, using screws for IMF, using the international diagnosis code for mandibular fracture, DS026, were anonymously selected (Department of Oral and Maxillofacial...... Surgery, Rigshospitalet, University Hospital of Copenhagen, Copenhagen, Denmark). The fracture type, radiographic findings, treatment modality, screw type and number, and root damage were recorded. For the outcome comparison, a review of the published data regarding iatrogenic dental root damage caused...

The Rabbit Stream Cipher

DEFF Research Database (Denmark)

Boesgaard, Martin; Vesterager, Mette; Zenner, Erik

2008-01-01

The stream cipher Rabbit was first presented at FSE 2003, and no attacks against it have been published until now. With a measured encryption/decryption speed of 3.7 clock cycles per byte on a Pentium III processor, Rabbit does also provide very high performance. This paper gives a concise...... description of the Rabbit design and some of the cryptanalytic results available....

[A toddler with a mandibular fracture].

Science.gov (United States)

van der Linden, E L; Bun, R J; van Os, E

2017-01-01

Mandibular fractures are rare in children. Symptoms of these fractures include preauricular pain and swelling, trismus and pain when opening the mouth, and they are often preceded by a fall on the chin. If the diagnosis is missed they may have serious consequences for the growth and development of the jaw. A 3-year-old boy was referred with a swelling in his left cheek, fever and vomiting. Two days earlier he had fallen on his chin. At physical examination he had severe preauricular pain on palpation and a trismus. The patient was admitted because of suspicion of a viral parotitis and the threat of dehydration. After discharge, he went to the dentist for examination of a molar that was painful to the touch. The dentist performed an orthopantomogram and discovered a fracture of the left mandibular collum. Any child with trauma to the chin should be observed for symptoms of a mandibular fracture, and if it seems necessary non-invasive radiographic examination should be performed.

Trigeminocardiac reflex by mandibular extension on rat pial microcirculation: role of nitric oxide.

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Dominga Lapi

Full Text Available In the present study we have extended our previous findings about the effects of 10 minutes of passive mandibular extension in anesthetized Wistar rats. By prolonging the observation time to 3 hours, we showed that 10 minutes mandibular extension caused a significant reduction of the mean arterial blood pressure and heart rate respect to baseline values, which persisted up to 160 minutes after mandibular extension. These effects were accompanied by a characteristic biphasic response of pial arterioles: during mandibular extension, pial arterioles constricted and after mandibular extension dilated for the whole observation period. Interestingly, the administration of the opioid receptor antagonist naloxone abolished the vasoconstriction observed during mandibular extension, while the administration of Nω-Nitro-L-arginine methyl ester, a nitric oxide synthase inhibitor, abolished the vasodilation observed after mandibular extension. Either drug did not affect the reduction of mean arterial blood pressure and heart rate induced by mandibular extension. By qRT-PCR, we also showed that neuronal nitric oxide synthase gene expression was significantly increased compared with baseline conditions during and after mandibular extension and endothelial nitric oxide synthase gene expression markedly increased at 2 hours after mandibular extension. Finally, western blotting detected a significant increase in neuronal and endothelial nitric oxide synthase protein expression. In conclusion mandibular extension caused complex effects on pial microcirculation involving opioid receptor activation and nitric oxide release by both neurons and endothelial vascular cells at different times.

Standardized perfusion value of the esophageal carcinoma and its correlation with quantitative CT perfusion parameter values

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Djuric-Stefanovic, A., E-mail: avstefan@eunet.rs [Faculty of Medicine, University of Belgrade, Belgrade (Serbia); Unit of Digestive Radiology (First University Surgical Clinic), Center of Radiology and MR, Clinical Center of Serbia, Belgrade (Serbia); Saranovic, Dj., E-mail: crvzve4@gmail.com [Faculty of Medicine, University of Belgrade, Belgrade (Serbia); Unit of Digestive Radiology (First University Surgical Clinic), Center of Radiology and MR, Clinical Center of Serbia, Belgrade (Serbia); Sobic-Saranovic, D., E-mail: dsobic2@gmail.com [Faculty of Medicine, University of Belgrade, Belgrade (Serbia); Center of Nuclear Medicine, Clinical Center of Serbia, Belgrade (Serbia); Masulovic, D., E-mail: draganmasulovic@yahoo.com [Faculty of Medicine, University of Belgrade, Belgrade (Serbia); Unit of Digestive Radiology (First University Surgical Clinic), Center of Radiology and MR, Clinical Center of Serbia, Belgrade (Serbia); Artiko, V., E-mail: veraart@beotel.rs [Faculty of Medicine, University of Belgrade, Belgrade (Serbia); Center of Nuclear Medicine, Clinical Center of Serbia, Belgrade (Serbia)

2015-03-15

Purpose: Standardized perfusion value (SPV) is a universal indicator of tissue perfusion, normalized to the whole-body perfusion, which was proposed to simplify, unify and allow the interchangeability among the perfusion measurements and comparison between the tumor perfusion and metabolism. The aims of our study were to assess the standardized perfusion value (SPV) of the esophageal carcinoma, and its correlation with quantitative CT perfusion measurements: blood flow (BF), blood volume (BV), mean transit time (MTT) and permeability surface area product (PS) of the same tumor volume samples, which were obtained by deconvolution-based CT perfusion analysis. Methods: Forty CT perfusion studies of the esophageal cancer were analyzed, using the commercial deconvolution-based CT perfusion software (Perfusion 3.0, GE Healthcare). The SPV of the esophageal tumor and neighboring skeletal muscle were correlated with the corresponding mean tumor and muscle quantitative CT perfusion parameter values, using Spearman's rank correlation coefficient (r{sub S}). Results: Median SPV of the esophageal carcinoma (7.1; range: 2.8–13.4) significantly differed from the SPV of the skeletal muscle (median: 1.0; range: 0.4–2.4), (Z = −5.511, p < 0.001). The cut-off value of the SPV of 2.5 enabled discrimination of esophageal cancer from the skeletal muscle with sensitivity and specificity of 100%. SPV of the esophageal carcinoma significantly correlated with corresponding tumor BF (r{sub S} = 0.484, p = 0.002), BV (r{sub S} = 0.637, p < 0.001) and PS (r{sub S} = 0.432, p = 0.005), and SPV of the skeletal muscle significantly correlated with corresponding muscle BF (r{sub S} = 0.573, p < 0.001), BV (r{sub S} = 0.849, p < 0.001) and PS (r{sub S} = 0.761, p < 0.001). Conclusions: We presented a database of the SPV for the esophageal cancer and proved that SPV of the esophageal neoplasm significantly differs from the SPV of the skeletal muscle, which represented a sample of healthy

Coronal views of the paediatric mandibular condyle on ...

African Journals Online (AJOL)

This article highlights the importance of routinely reviewing the mandibular condyle on computerised tomography brain studies in a trauma setting, that often extends to involve the mandibular condyles in the scan parameters. We discuss 4 cases seen over the last 18 months at our institution, and review the relevant ...

Osteochondroma of the mandibular condyle

Directory of Open Access Journals (Sweden)

Ashish Kumar

2011-01-01

Full Text Available Osteochondroma (OC of the mandibular condyle is a relatively rare condition that causes a progressive enlargement of the condyle, usually resulting in facial asymmetry, temporomandibular joint (TMJ dysfunction, and malocclusion. Radiographically, there is a unilaterally enlarged condyle usually with an exophytic outgrowth of the tumor from the condylar head. We present a case of a left mandibular condylar OC that created a major facial asymmetry, malocclusion, and TMJ dysfunction. Discussion includes the rationale for treatment and the method used in this case. In actively growing OCs, surgical intervention is indicated to remove the tumor stopping the benign growth process and improve facial symmetry, occlusion, and jaw function.

Early quantification of the therapeutic efficacy of the vascular disrupting agent, CKD-516, using dynamic contrast-enhanced ultrasonography in rabbit VX2 liver tumors

Energy Technology Data Exchange (ETDEWEB)

Joo, Ijin; Kim, Jung Hoon; Lee, Jeong Min; Choi, Jin Woo; Han, Joon Koo; Choi, Byung Ihn [Dept. of Radiology, Seoul National University Hospital, Seoul (Korea, Republic of)

2014-03-15

To evaluate the usefulness of dynamic contrast-enhanced ultrasonography (DCE-US) in the early quantification of hemodynamic change following administration of the vascular disrupting agent (VDA) CKD-516 using a rabbit VX2 liver tumor model. This study was approved by our institutional animal care and use committee. Eight VX2 liver-tumor-bearing rabbits were treated with intravenous CKD-516, and all underwent DCE-US using SonoVue before and again 2, 4, 6, and 24 hours following their treatment. The tumor perfusion parameters were obtained from the time-intensity curve of the DCE-US data. Repeated measures analysis of variance was performed to assess any significant change in tumor perfusion over time. Relative changes in the DCE-US parameters between the baseline and follow-up assessments were correlated with the relative changes in tumor size over the course of seven days using Pearson correlation. CKD-516 treatment resulted in significant changes in the DCE-US parameters, including the peak intensity, total area under the time-intensity curve (AUCtotal), and AUC during wash-out (AUCout) over time (P<0.05). Pairwise comparison tests revealed that the AUCtotal and AUC during wash-in (AUCin) seen on the two-hour follow-up were significantly lower than the baseline values (P<0.05). However, none of early changes in the DCE-US parameters until 24-hour follow-up showed a significant correlation with the relative changes in tumor size during seven days after CKD-516 treatment. Our results suggest that a novel VDA (CKD-516) can cause disruption of tumor perfusion as early as two hours after treatment and that the therapeutic effect of CKD-516 treatment can be effectively quantified using DCE-US.

Nuclear magnetic resonance of perfused tissue

International Nuclear Information System (INIS)

Harpen, M.D.; Allison, R.C.

1986-01-01

The effect of perfusion on the NMR signal observed in NMR imaging is studied in a phantom and in two isolated perfused canine lungs. It is observed that perfusion in tissue has little effect on longitudinal relaxation times. Transverse relaxation rates are observed to correlate linearly with rates of perfusion, in accordance with a model presented. (author)

Dynamic CT myocardial perfusion imaging identifies early perfusion abnormalities in diabetes and hypertension : Insights from a multicenter registry

NARCIS (Netherlands)

Vliegenthart, Rozemarijn; De Cecco, Carlo N.; Wichmann, Julian L.; Meinel, Felix G.; Pelgrim, Gert Jan; Tesche, Christian; Ebersberger, Ullrich; Pugliese, Francesca; Bamberg, Fabian; Choe, Yeon Hyeon; Wang, Yining; Schoepf, U. Joseph

2016-01-01

Background: To identify patients with early signs of myocardial perfusion reduction, a reference base for perfusion measures is needed. Objective: To analyze perfusion parameters derived from dynamic computed tomography perfusion imaging (CTPI) in patients with suspected coronary artery disease

Orthodontic Extraction of High-Risk Impacted Mandibular Third Molars in Close Proximity to the Mandibular Canal: A Systematic Review.

Science.gov (United States)

Kalantar Motamedi, Mahmood Reza; Heidarpour, Majid; Siadat, Sara; Kalantar Motamedi, Alimohammad; Bahreman, Ali Akbar

2015-09-01

Extraction of mandibular third molars (M3s) in close proximity to the mandibular canal has some inherent risks to adjacent structures, such as neurologic damage to teeth, bone defects distal to the mandibular second molar (M2), or pathologic fractures in association with enlarged dentigerous cysts. The procedure for extrusion and subsequent extraction of high-risk M3s is called orthodontic extraction. This is a systematic review of the available approaches for orthodontic extraction of impacted mandibular M3s in close proximity to the mandibular canal and their outcomes. The PubMed, Scopus, Cochrane Central Register of Controlled Trials (CENTRAL), DOAJ, Google Scholar, OpenGrey, Iranian Science Information Database (SID), Iranmedex, and Irandoc databases were searched using specific keywords up to June 2, 2014. Studies were evaluated based on predetermined eligibility criteria, treatment approaches, and their outcomes. Thirteen articles met the inclusion criteria. A total of 123 impacted teeth were extracted by orthodontic extraction and 2 cases were complicated by transient paresthesia. Three types of biomechanical approaches were used: 1) using the posterior maxillary region as the anchor for orthodontic extrusion of lower M3s, 2) simple cantilever springs attached to the M3 buttonhole, and 3) cantilever springs tied to a bonded orthodontic bracket on the M3 plus multiple-loop spring wire for distal movement of the M3. Osteo-periodontal status of M2s also improved uneventfully. Despite the drawbacks of orthodontic extraction, removal of deeply impacted M3s using the described techniques is safe with regard to mandibular nerve injury and neurologic damage. Orthodontic extraction is recommended for extraction of impacted M3s that present a high risk of postoperative osteo-periodontal defects on the distal surface of the adjacent M2 and those associated with dentigerous cysts. Copyright © 2015 American Association of Oral and Maxillofacial Surgeons. Published by

Evaluation of femoral perfusion using dynamic contrast-enhanced MRI after simultaneous initiation of electrical stimulation and steroid treatment in an osteonecrosis model.

Science.gov (United States)

Yamamoto, Hiroki; Ueshima, Keiichiro; Saito, Masazumi; Ikoma, Kazuya; Ishida, Masashi; Goto, Tsuyoshi; Hayashi, Shigeki; Ikegami, Akira; Fujioka, Mikihiro; Mazda, Osam; Kubo, Toshikazu

2018-04-30

This study aimed to evaluate femoral perfusion using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) for two weeks after the simultaneous initiation of electrical stimulation (ES) and steroid treatment in a steroid-induced osteonecrosis (ON) model. A single dose of methylprednisolone was injected into 14 rabbits. Seven rabbits underwent ES (ES group), and seven rabbits did not (control group). DCE-MRI was performed before steroid administration and 1, 5, 10, and 14 days after steroid administration. Regions of interest were set in the bilateral proximal femora. The enhancement ratio, initial slope, and area under the curve were analyzed. These parameters were evaluated after steroid administration in each group and between the two groups, and the ratios of ON in both groups were compared. In the control group, the minimum values of all parameters decreased significantly after steroid administration (P < 0.05), but in the ES group, the parameters did not decrease. In the ES group, all parameter values were significantly increased on the 10th and 14th days (P < 0.05). All parameter values in the ES group were significantly higher than those in the control group on the 14th day (P < 0.05). In the control group, ON was detected in three of five rabbits (in three of ten femora). In the ES group, ON was not detected. These results suggest that increased femoral blood flow elicited by ES may be related to ON prevention after steroid administration.

Methodology for ventilation/perfusion SPECT

DEFF Research Database (Denmark)

Bajc, Marika; Neilly, Brian; Miniati, Massimo

2010-01-01

radiolabeled liquid aerosols are not restricted to the presence of obstructive lung disease. Radiolabeled macroaggregated human albumin is the imaging agent of choice for perfusion scintigraphy. An optimal combination of nuclide activities and acquisition times for ventilation and perfusion, collimators......Ventilation/perfusion single-photon emission computed tomography (V/Q SPECT) is the scintigraphic technique of choice for the diagnosis of pulmonary embolism and many other disorders that affect lung function. Data from recent ventilation studies show that the theoretic advantages of Technegas over......, and imaging matrix yields an adequate V/Q SPECT study in approximately 20 minutes of imaging time. The recommended protocol based on the patient remaining in an unchanged position during the initial ventilation study and the perfusion study allows presentation of matching ventilation and perfusion slices...

Experimental occlusal interferences. Part V. Mandibular rotations versus hemimandibular translations.

Science.gov (United States)

Christensen, L V; Rassouli, N M

1995-12-01

Frontal plane mandibular rotations and corresponding hemimandibular translations were studied in vitro by using direct observations of a human cadaver mandible and in vivo by using the indirect observations of rotational electrognathography. A comparison between the two methods showed that rotational electrognathography erred in measuring the clinically relevant hemimandibular translations resulting from mandibular rotations having a unilateral molar point (simulated occlusal interference) as the pivot of frontal plane torque. In vitro frontal plane rotations about a unilateral mandibular molar tooth (simulated occlusal interference) suggested that the resulting hemimandibular upward translations of the lateral portion of the mandibular condyle, contralateral to the molar tooth, would cause considerable compressive loading of the temporomandibular joint disc.

RabbitMQ essentials

CERN Document Server

Dossot, David

2014-01-01

This book is a quick and concise introduction to RabbitMQ. Follow the unique case study of Clever Coney Media as they progressively discover how to fully utilize RabbitMQ, containing clever examples and detailed explanations.Whether you are someone who develops enterprise messaging products professionally or a hobbyist who is already familiar with open source Message Queuing software and you are looking for a new challenge, then this is the book for you. Although you should be familiar with Java, Ruby, and Python to get the most out of the examples, RabbitMQ Essentials will give you the push y

Hydrostatic determinants of cerebral perfusion

International Nuclear Information System (INIS)

Wagner, E.M.; Traystman, R.J.

1986-01-01

We examined the cerebral blood flow response to alterations in perfusion pressure mediated through decreases in mean arterial pressure, increases in cerebrospinal fluid (CSF) pressure, and increases in jugular venous (JV) pressure in 42 pentobarbital anesthetized dogs. Each of these three pressures was independently controlled. Cerebral perfusion pressure was defined as mean arterial pressure minus JV or CSF pressure, depending on which was greater. Mean hemispheric blood flow was measured with the radiolabeled microsphere technique. Despite 30-mm Hg reductions in mean arterial pressure or increases in CSF or JV pressure, CBF did not change as long as the perfusion pressure remained greater than approximately 60 mm Hg. However, whenever perfusion pressure was reduced to an average of 48 mm Hg, cerebral blood flow decreased 27% to 33%. These results demonstrate the capacity of the cerebral vascular bed to respond similarly to changes in the perfusion pressure gradient obtained by decreasing mean arterial pressure, increasing JV pressure or increasing CSF pressure, and thereby support the above definition of cerebral perfusion pressure

Predicting pathology in impacted mandibular third molars

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Aveek Mukherji

2017-01-01

Full Text Available Introduction: The rising incidence of the impacted mandibular third molars and their association with pathologies is now considered a public health problem. Aims and Objectives: The objective of this study was to assess the position of impacted mandibular third molars that are prone to developing pathologies and to determine the frequency and type of pathological conditions associated with these impacted teeth to facilitate planning for their prophylactic removal. Materials and Methods: Consecutive panoramic radiographs and clinical examination of 300 patients with impacted mandibular third molars were collected. They were segregated according to Pell and Gregory’s classification, Winter’s classification, and according to their state of eruption. These were correlated with associated pathologies based on clinical and radiological criteria. Statistical Analysis Used: Descriptive statistics included computation of percentages, mean, and standard deviations. The statistical test applied for the analysis was Pearson’s Chi-square test (χ2. For this test, confidence interval and P value were set at 93% and ≤0.03, respectively. Results: The pathology most commonly associated with impacted third molars was pericoronitis, which had the highest frequency of occurrence in partially erupted, distoangular, and IA positioned (as per Pell and Gregory classification impacted teeth. Impacted mandibular third molars, which were in IA position, placed mesially, and partially erupted, were prone to develop pathologies such as dental caries and periodontitis. Conclusion: The clinical and radiographical features of impacted third molar may be correlated to the development of their pathological complications. The partially impacted mandibular third molars with mesioangularly aligned in IA position have the highest potential to cause pathological complications.

Pediatric mandibular fractures: a free hand technique.

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Davison, S P; Clifton, M S; Davison, M N; Hedrick, M; Sotereanos, G

2001-01-01

The treatment of pediatric mandibular fractures is rare, controversial, and complicated by mixed dentition. To determine if open mandibular fracture repair with intraoral and extraoral rigid plate placement, after free hand occlusal and bone reduction, without intermaxillary fixation (IMF), is appropriate and to discuss postoperative advantages, namely, maximal early return of function and minimal oral hygiene issues. A group of 29 pediatric patients with a mandibular fracture were examined. Twenty pediatric patients (13 males and 7 females) with a mean age of 9 years (age range, 1-17 years) were treated using IMF. All patients were treated by the same surgeon (G.S.). Surgical time for plating was reduced by 1 hour, the average time to place patients in IMF. The patients who underwent open reduction internal fixation without IMF ate a soft mechanical diet by postoperative day 3 compared with postoperative day 16 for those who underwent IMF. Complication rates related to fixation technique were comparable at 20% for those who did not undergo IMF and 33% for those who did. We believe that free hand reduction is a valuable technique to reduce operative time for pediatric mandibular fractures. It maximizes return to function while minimizing the oral hygiene issues and hardware removal of intermaxillary function.

Forced extrusion for removal of impacted third molars close to the mandibular canal Extrusión forzada para extraer los terceros molares impactados cerca del canal mandibular

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Dennis Flanagan DDS

2012-03-01

Full Text Available Impacted mandibular third molars can be located in close proximity to the mandibular canal. This creates a risk for the nerve or artery injury. These are contained in the canal. However, the impacted third molar can be moved coronally by orthodontic means, after removal of overlying bone, and safely extracted. The orthodontic intervention slowly moves the tooth apex away from the mandibular canal and reduces the potential for a neural injury. This method may be useful for older patients with root apices that approximate or are actually located in the mandibular canal. This technique needs further study. There is a theoretical potential for neural or arterial injury from physical contact of the tooth apex as it moves by or through the mandibular canal.Los terceros molares inferiores impactados pueden localizarse muy cerca del canal mandibular. Esto constituye un riesgo de lesión del nervio o la arteria, que se localizan dentro del canal. No obstante, el tercer molar impactado puede desplazarse en dirección coronal con ortodoncia, tras ostectomía del hueso suprayacente, y extraerse sin riesgos. La intervención ortodóncica desplaza lentamente el ápice del diente fuera del canal mandibular y reduce la posibilidad de lesión neural. Este método puede ser útil para pacientes de edad avanzada con ápices dentales que se aproximan o en realidad se localizan en el canal mandibular. La técnica necesita un estudio adicional. Hay la posibilidad teórica de lesión neural o arterial a partir del contacto físico del ápice del diente a medida que se desplaza a través del canal mandibular.

Serological Survey for RHD Antibodies in Rabbits from Two Types of Rabbit Breeding Farms.

Science.gov (United States)

Fitzner, A; Niedbalski, W

2016-09-01

Seroprevalence studies of RHDV antibodies in domestic rabbits were conducted between 2008-2014. A total of 12,169 sera from the provinces of central, southern and south-east Poland, including 7,570 samples collected from mixed-breed rabbits reared in smallholder farms and nearly 4,600 sera taken mainly from unvaccinated rabbits kept in industrial farms, were examined using ELISA tests. Additionally, cross-reactivity of selected tested and control archival sera using both classic RHDV and RHDVa antigens was determined by HI assay. The overall seroprevalence was 13.3%. In rabbits with unkown history of immunisation or RHD infection which came from small farms, RHDV antibodies were detected in 6.1% ranging between 1.0% to 17.2% of animals. In rabbits of the same group, but with a declared vaccination status, or confirmed exposure to an infectious virus, or coming from exposed females, the seroprevalence ranged from 83% to 100%. Among unvaccinated meat rabbits aged 71 to 90 days from industrial farms, low (1.85%, 4.17%, 11%), medium (34%, 54%) or high rates (98.7%) of seropositivity were detected. The seroconversion recorded in adult vaccinated females from industrial farms was 70% and 95%. Generally, the antibody levels examined by ELISAs and HI were comparable. However, a number of sera from the rabbits from small farms, as well as archival sera, showed clear differences. Several-fold differences in antibody titers, evidenced mainly in the postoutbreak sera, indictaed the contact of animals with RHDVa antigen. The overall results of the survey revealed a great proportion of seronegative rabbits potentially highly susceptible to RHD infection. In combination with the emergence of a novel pathogenic RHD virus type (RHDV2), it poses a severe risk of a next wave of fatal disease cases spreading in the native population of domestic rabbits, especially in farms with a traditional system of husbandry.

Radiographic evaluation of the course and visibility of the mandibular canal

International Nuclear Information System (INIS)

Jung, Yun Hoa; Cho, Bong Hae

2014-01-01

This study was performed to investigate the course of the mandibular canal on panoramic radiography and the visibility of this canal on both panoramic radiography and cone-beam computed tomography (CBCT). The study consisted of panoramic radiographs and CBCT images from 262 patients. The course of the mandibular canal, as seen in panoramic radiographs, was classified into four types: linear, elliptical, spoon-shaped, and turning curves. The visibility of this canal from the first to the third molar region was evaluated by visually determining whether the mandibular canal was clearly visible, probably visible, or invisible. The visibility of the canal on panoramic radiographs was compared with that on CBCT images. Elliptical curves were most frequently observed along the course of the mandibular canal. The percentage of clearly visible mandibular canals was the highest among the spoon-shaped curves and the lowest among the linear curves. On panoramic radiographs, invisible mandibular canals were found in 22.7% of the examined sites in the first molar region, 11.8% in the second molar region, and 1.3% in the third molar region. On CBCT cross-sectional images, the mandibular canal was invisible in 8.2% of the examined sites in the first molar region, 5.7% in the second molar region, and 0.2% in the third molar region. The visibility of this canal was lower in the first molar region than in the third molar region. The mandibular canal presented better visibility on CBCT images than on panoramic radiographs.

Mandibular ramus fractures: a rarity.

Science.gov (United States)

Kale, Tejraj Pundalik; Kotrashetti, S M; Louis, Archana; Lingaraj, J B; Sarvesh, B U

2013-01-01

To determine the incidence of mandibular ramus fractures in KLE's PK Hospital and to analyze the outcome of open reduction and internal fixation of these fractures. Using a retrospective study design, records of all trauma patients who reported to the Department of Oral and Maxillofacial Surgery, KLE's PK Hospital Belgaum, between the years January 2006 to October 2011 was obtained from the medical records office. The data variables that were analyzed were the name, age, sex, cause of injury, pretreatment occlusion, treatment given, period of MMF and post-treatment occlusion. Total number of mandibular fracture cases was 298. Ramus fractures were 10 in number which accounted for 3.3% of fractures. The age range of these 10 patients was seen to be between 20 to 80 years with the average age being 35.6 years. Of these 10 patients, 9 were male and 1 was female and 7 patients were treated by open reduction and internal fixation and the remaining 3 by closed reduction. The average period of MMF was 3 days for the patients who underwent open reduction and internal fixation. There was improvement in occlusion in all 10 patients post-treatment and there was no complication reported in any of the cases. Ramus fractures accounted for 3.3% of all mandibular fractures. Open reduction and internal fixation of ramus fractures ensures adequate functional and anatomic reduction. This study makes an attempt to throw a light on the increasing incidence of ramus fractures and a successful management of these fractures by open reduction and internal fixation. How to cite this article: Kale TP, Kotrashetti SM, Louis A, Lingaraj JB, Sarvesh BU. Mandibular Ramus Fractures: A Rarity. J Contemp Dent Pract 2013;14(1):39-42. Source of support: Nil Conflict of interest: None declared.

Hemocoagulase Combined with Microbubble-Enhanced Ultrasound Cavitation for Augmented Ablation of Microvasculature in Rabbit VX2 Liver Tumors.

Science.gov (United States)

Yang, Qian; Tang, Peng; He, Guangbin; Ge, Shuping; Liu, Liwen; Zhou, Xiaodong

2017-08-01

We investigated a new method for combining microbubble-enhanced ultrasound cavitation (MEUC) with hemocoagulase (HC) atrox. Our goal was to induce embolic effects in the vasculature and combine these with an anti-angiogenic treatment strategy. Fourteen days after being implanted with a single slice of the liver VX2 tumor, rabbits were randomly divided into five groups: (i) a control group injected intra-venously with saline using a micropump; (ii) a group given only an injection of HC; (iii) a group treated only with ultrasound cavitation; (iv) a group treated with MEUC; (v) a group treated with MEUC + HC. Contrast-enhanced ultrasound was performed before treatment and 1 h and 7 d post-treatment to measure tumor size, enhancement and necrosis range. QontraXt software was used to determine the time-intensity curve of tumor blood perfusion and microvascular changes. At 1 h and 7 d after treatment with MEUC + HC, the parameters of the time-intensity curve, which included peak value, regional blood volume, regional blood flow and area under the curve value and which were measured using contrast-enhanced ultrasound, were significantly lower than those of the other treatment groups. The MEUC + HC treatment group exhibited significant growth inhibition relative to the ultrasound cavitation only, HC and MEUC treatment groups. No damage was observed in the surrounding normal tissues. These results support the feasibility of reducing the blood perfusion of rabbit VX2 liver tumors using a new method that combines MEUC and HC. Copyright © 2017 World Federation for Ultrasound in Medicine & Biology. All rights reserved.

Chest wall restriction limits high airway pressure-induced lung injury in young rabbits.

Science.gov (United States)

Hernandez, L A; Peevy, K J; Moise, A A; Parker, J C

1989-05-01

High peak inspiratory pressures (PIP) during mechanical ventilation can induce lung injury. In the present study we compare the respective roles of high tidal volume with high PIP in intact immature rabbits to determine whether the increase in capillary permeability is the result of overdistension of the lung or direct pressure effects. New Zealand White rabbits were assigned to one of three protocols, which produced different degrees of inspiratory volume limitation: intact closed-chest animals (CC), closed-chest animals with a full-body plaster cast (C), and isolated excised lungs (IL). The intact animals were ventilated at 15, 30, or 45 cmH2O PIP for 1 h, and the lungs of the CC and C groups were placed in an isolated lung perfusion system. Microvascular permeability was evaluated using the capillary filtration coefficient (Kfc). Base-line Kfc for isolated lungs before ventilation was 0.33 +/- 0.31 ml.min-1.cmH2O-1.100g-1 and was not different from the Kfc in the CC group ventilated with 15 cmH2O PIP. Kfc increased by 850% after ventilation with only 15 cmH2O PIP in the unrestricted IL group, and in the CC group Kfc increased by 31% after 30 cmH2O PIP and 430% after 45 cmH2O PIP. Inspiratory volume limitation by the plaster cast in the C group prevented any significant increase in Kfc at the PIP values used. These data indicate that volume distension of the lung rather than high PIP per se produces microvascular damage in the immature rabbit lung.

Detection of reactive oxygen species in isolated, perfused lungs by electron spin resonance spectroscopy

Directory of Open Access Journals (Sweden)

Schudt Christian

2005-07-01

Full Text Available Abstract Background The sources and measurement of reactive oxygen species (ROS in intact organs are largely unresolved. This may be related to methodological problems associated with the techniques currently employed for ROS detection. Electron spin resonance (ESR with spin trapping is a specific method for ROS detection, and may address some these technical problems. Methods We have established a protocol for the measurement of intravascular ROS release from isolated buffer-perfused and ventilated rabbit and mouse lungs, combining lung perfusion with the spin probe l-hydroxy-3-carboxy-2,2,5,5-tetramethylpyrrolidine (CPH and ESR spectroscopy. We then employed this technique to characterize hypoxia-dependent ROS release, with specific attention paid to NADPH oxidase-dependent superoxide formation as a possible vasoconstrictor pathway. Results While perfusing lungs with CPH over a range of inspired oxygen concentrations (1–21 %, the rate of CP• formation exhibited an oxygen-dependence, with a minimum at 2.5 % O2. Addition of superoxide dismutase (SOD to the buffer fluid illustrated that a minor proportion of this intravascular ROS leak was attributable to superoxide. Stimulation of the lungs by injection of phorbol-12-myristate-13-acetate (PMA into the pulmonary artery caused a rapid increase in CP• formation, concomitant with pulmonary vasoconstriction. Both the PMA-induced CPH oxidation and the vasoconstrictor response were largely suppressed by SOD. When the PMA challenge was performed at different oxygen concentrations, maximum superoxide liberation and pulmonary vasoconstriction occurred at 5 % O2. Using a NADPH oxidase inhibitor and NADPH-oxidase deficient mice, we illustrated that the PMA-induced superoxide release was attributable to the stimulation of NADPH oxidases. Conclusion The perfusion of isolated lungs with CPH is suitable for detection of intravascular ROS release by ESR spectroscopy. We employed this technique to

Cerebro-costo-mandibular syndrome: Report of two cases.

Science.gov (United States)

Abdalla, Wael; Panigrahy, Ashok; Bartoletti, Stefano C

2011-01-01

Cerebro-costo-mandibular syndrome (CCMS) is a rare syndrome that includes a constellation of mandibular hypoplasia and posterior rib defects as its basic features. Additional features can include hearing loss, tracheal cartilage abnormalities, scoliosis, elbow hypoplasia, and spina bifida. Here we report two cases of CCMS and discuss the reported long-term outcome of the disease.

Pearls of mandibular trauma management.

Science.gov (United States)

Koshy, John C; Feldman, Evan M; Chike-Obi, Chuma J; Bullocks, Jamal M

2010-11-01

Mandibular trauma is a common problem seen by plastic surgeons. When fractures occur, they have the ability to affect the patient's occlusion significantly, cause infection, and lead to considerable pain. Interventions to prevent these sequelae require either closed or open forms of reduction and fixation. Physicians determining how to manage these injuries should take into consideration the nature of the injury, background information regarding the patient's health, and the patient's comorbidities. Whereas general principles guide the management of the majority of injuries, special consideration must be paid to the edentulous patient, complex and comminuted fractures, and pediatric patients. These topics are discussed in this article, with a special emphasis on pearls of mandibular trauma management.

Intra-Arterial MR Perfusion Imaging of Meningiomas: Comparison to Digital Subtraction Angiography and Intravenous MR Perfusion Imaging.

Directory of Open Access Journals (Sweden)

Mark A Lum

Full Text Available To evaluate the ability of IA MR perfusion to characterize meningioma blood supply.Studies were performed in a suite comprised of an x-ray angiography unit and 1.5T MR scanner that permitted intraprocedural patient movement between the imaging modalities. Patients underwent intra-arterial (IA and intravenous (IV T2* dynamic susceptibility MR perfusion immediately prior to meningioma embolization. Regional tumor arterial supply was characterized by digital subtraction angiography and classified as external carotid artery (ECA dural, internal carotid artery (ICA dural, or pial. MR perfusion data regions of interest (ROIs were analyzed in regions with different vascular supply to extract peak height, full-width at half-maximum (FWHM, relative cerebral blood flow (rCBF, relative cerebral blood volume (rCBV, and mean transit time (MTT. Linear mixed modeling was used to identify perfusion curve parameter differences for each ROI for IA and IV MR imaging techniques. IA vs. IV perfusion parameters were also directly compared for each ROI using linear mixed modeling.18 ROIs were analyzed in 12 patients. Arterial supply was identified as ECA dural (n = 11, ICA dural (n = 4, or pial (n = 3. FWHM, rCBV, and rCBF showed statistically significant differences between ROIs for IA MR perfusion. Peak Height and FWHM showed statistically significant differences between ROIs for IV MR perfusion. RCBV and MTT were significantly lower for IA perfusion in the Dural ECA compared to IV perfusion. Relative CBF in IA MR was found to be significantly higher in the Dural ICA region and MTT significantly lower compared to IV perfusion.

Pulmonary perfusion ''without ventilation''

International Nuclear Information System (INIS)

Chapman, C.N.; Sziklas, J.J.; Spencer, R.P.; Rosenberg, R.J.

1983-01-01

An 88-yr-old man, with prior left upper lobectomy and phrenic nerve injury, had a ventilation/perfusion lung image. Both wash-in and equilibrium ventilation images showed no radioactive gas in the left lung. Nevertheless, the left lung was perfused. A similar result was obtained on a repeat study 8 days later. Delayed images, during washout, showed some radioactive gas in the left lung. Nearly absent ventilation (but continued perfusion) of that lung might have been related to altered gas dynamics brought about by the prior lobectomy, a submucosal bronchial lesion, phrenic nerve damage, and limited motion of the left part of the diaphragm. This case raises the issue of the degree of ventilation (and the phase relationship between the lungs) required for the entry of radioactive gas into a diseased lung, and the production of a ''reversed ventilation/perfusion mismatch.''

Experimental occlusal interferences. Part III. Mandibular rotations induced by a rigid interference.

Science.gov (United States)

Rassouli, N M; Christensen, L V

1995-10-01

A rigid intercuspal interference (minimum mean height of 0.24 mm) was placed on either the right or left mandibular second premolar and first molar of 12 subjects. During brisk and forceful biting on the interference, rotational electrognathography measured maximum torque of the right and left mandibular condyles in the frontal and horizontal planes of orientation. All subjects showed frontal plan upward rotation (mean of 0.7 degrees) of the mandibular condyle contralateral to the interference. In 33% of the subjects there was no horizontal plane backward rotation. In 58% of the subjects there was horizontal plane backward rotation (mean of 0.5 degrees) of the mandibular condyle ipsilateral to the interference, and in one subject (8%) there was backward horizontal plane rotation (0.1 degree) of the mandibular condyle contralateral to the interference. It was inferred that the masseter muscle, ipsilateral to the interference, generated negative work in order to decelerate frontal plane 'unseating' of the mandibular condyle ipsilateral to the interference. It was inferred that the masseter muscle, contralateral to the interference, produced positive work in order to accelerate frontal plane 'seating' of the mandibular condyle contralateral to the interference. Finally, it was speculated that the impact forces of frontal plane 'seating' of the mandibular condyle, contralateral to the interference, might lead to 'vacuum sticking' of the temporomandibular joint disc because of the formation of negative hydrostatic pressures.

Maxillary advancement for mandibular prognathism: indications and rationale.

Science.gov (United States)

Rosen, H M

1991-05-01

The surgical correction of mandibular prognathism has traditionally involved posterior repositioning of the mandibular body. This treatment approach corrects the skeletal disproportion at the expense of reducing facial skeletal volume and can unpredictably result in inadequately supported soft tissues with loss of skeletal definition. In an effort to avoid these sequelae of mandibular reduction, 18 patients diagnosed as having mandibular prognathism were treated with maxillary advancement surgery at the Le Fort I level. Mean patient SNB angle was 85.2 degrees, as compared with a normal 79 +/- 3 degrees. Maxillae were documented to be in normal position relative to both cranial base and Frankfort horizontal. The mean maxillary advancement was 6.9 mm, with a range of 4.5 to 8.8 mm. All patients required genioplasty to reduce vertical chin height and/or to laterally shift the chin. At the time of follow-up (mean 16.2 months), all patients retained cephalometric data suggestive of enlarged mandibles and excessive anterior facial divergence. However, maxillomandibular harmony and facial convexity had been restored without sacrificing skeletal volume. Treatment results demonstrated these faces to be skeletally well proportioned despite lower face protrusion that was beyond "normal." Postoperative appearances were characterized by a well-supported soft-tissue envelope and a highlighted skeletal foundation, creating angular, well-defined lower faces. These findings support the credibility of maxillary advancement as the procedure of choice in selected individuals with mandibular prognathism. Indications and an aesthetic rationale for this surgical approach are presented.

Simple Additive Weighting to Diagnose Rabbit Disease

Science.gov (United States)

Ramadiani; Marissa, Dyna; Jundillah, Muhammad Labib; Azainil; Hatta, Heliza Rahmania

2018-02-01

Rabbit is one of the many pets maintained by the general public in Indonesia. Like other pet, rabbits are also susceptible to various diseases. Society in general does not understand correctly the type of rabbit disease and the way of treatment. To help care for sick rabbits it is necessary a decision support system recommendation diagnosis of rabbit disease. The purpose of this research is to make the application of rabbit disease diagnosis system so that can help user in taking care of rabbit. This application diagnoses the disease by tracing the symptoms and calculating the recommendation of the disease using Simple Additive Weighting method. This research produces a web-based decision support system that is used to help rabbit breeders and the general public.

Mandibular pseudocarcinomatous hyperplasia.

Science.gov (United States)

Warter, A; Walter, P; Meyer, C; Barrière, P; Galatir, L; Wilk, A

2000-08-01

Three unusual cases of pseudocarcinomatous (pseudoepitheliomatous) hyperplasia (PH) affecting chronic osteomyelitic mandibular sequestra are reported to highlight the differences with the various squamous neoplasms which occur in that site. In two patients carrying a mandibular graft following the excision of an ameloblastoma, mucosal ulcers resulted in chronic osteomyelitis. In a third patient, an apical dental infection was associated with fistulated osteomyelitis. Histology of the three sequestra showed an intraosseous squamous proliferation. It was characterized by a peripheral involvement of medullary spaces, the more mature epithelial layer covering the bone trabeculae without intervening stroma, and the basal type epithelial layer surrounding a central fibrovascular core. There were no histological or cytological signs of malignancy. PH shows an inverted pattern when compared with the centro-medullary tumoural islands seen in the various oral or odontogenic squamous neoplasms which occur in the jaws. The lack of signs of malignancy distinguish PH from common squamous cell carcinomas. A short clinical course is an important feature in the distinction of PH from the well differentiated squamous cell carcinomas which may develop in fistulated chronic osteomyelitis.

Impaired Cerebellar Maturation, Growth Restriction, and Circulating Insulin-Like Growth Factor 1 in Preterm Rabbit Pups

Science.gov (United States)

Sveinsdóttir, Kristbjörg; Länsberg, John-Kalle; Sveinsdóttir, Snjólaug; Garwicz, Martin; Ohlsson, Lennart; Hellström, Ann; Smith, Lois; Gram, Magnus; Ley, David

2018-01-01

Cerebellar growth is impeded following very preterm birth in human infants and the observed reduction in cerebellar volume is associated with neurodevelopmental impairment. Decreased levels of circulating insulin-like growth factor 1 (IGF-1) are associated with decreased cerebellar volume. The relationship between preterm birth, circulating IGF-1, and key cell populations supporting cerebellar proliferation is unknown. The aim of this study was to evaluate the effect of preterm birth on postnatal growth, circulating IGF-1, and cerebellar maturation in a preterm rabbit pup model. Preterm rabbit pups (PT) were delivered by cesarean section at day 29 of gestation, cared for in closed incubators with humidified air, and gavage fed with formula. Control term pups (T) delivered by spontaneous vaginal delivery at day 32 of gestation were housed and fed by their lactating doe. In vivo perfusion-fixation for immunohistochemical evaluation of cerebellar proliferation, cell maturation, and apoptosis was performed at repeated time points in PT and T pups. Results show that the mean weight of the pups and circulating IGF-1 protein levels were lower in the PT group at all time points (p staining at P0 (p = 0.003), P2 (p = 0.004), and P5 (p = 0.04) in the PT group compared to in the T group. Staining for sonic hedgehog was positive in neuronal EGL progenitors and Purkinje cells at early time points but was restricted to a well-defined Purkinje cell monolayer at later time points. Preterm birth in rabbit pups is associated with lower circulating levels of IGF-1, decreased postnatal growth, and decreased cerebellar EGL proliferation and Purkinje cell maturation. The preterm rabbit pup model exhibits important characteristics of human preterm birth, and may thus be suitable for the evaluation of interventions aiming to modify growth and cerebellar development in the preterm population. PMID:28972955

Distracción mandibular y articulación temporomandibular Mandibular distraction and the temporomandibular joint

Directory of Open Access Journals (Sweden)

F. Monje Gil

2004-08-01

Full Text Available Los pacientes con deformidades craneofaciales requieren generalmente multiples y, a veces, complejos procedimientos quirurgicos para reconstruir tejidos blandos y duros alterados. Un avance importante en cirugía reconstructiva es el alargamiento de la mandibula por distracción que tiene la ventaja de una cirugía menos agresiva que determinados tipos de osteotomías. Con esta técnica una osteotomía bicortical se hace en distintas zonas de la mandibula colocandose el distractor hasta alcanzar los efectos deseados. Aunque las fuerzas aplicadas se han mostrado eficaces para alargar la mandíbula, sus efectos en segmentos proximales y distales, incluyendo la articulación temporomandibular no han sido analizados sistemáticamente. En este artículo se repasa trabajos experimentales y clínicos en los que se detalla la relación entre distracción mandibular y articulación temporomandibular.Abstract: Patients with severe craniofacial abnormalities often require multiple and complex surgical procedures to reconstruct maldeveloped hard and soft tissues of the maxillofacial complex. An important advance in reconstructive surgery is mandibular lengthening by gradual distraction, which takes advantage to be less agressive surgery than some osteotomies. With this technique, a bicortical osteotomy is made at the angle of the deficient mandible, and an expansion appliance is placed across the osteotomy line. Although the applied forces have been shown to lengthen the mandible effectively in the region of the application, their effects on the proximal and distal mandibular segments, including the temporomandibular joint region, have not been analyzed systematically. In this article, we study several experimental and clinical papers where it describes the relationship between mandibular distraction and temporomandibular joint.

Hepatic perfusion changes in an experimental model of acute pancreatitis: Evaluation by perfusion CT

International Nuclear Information System (INIS)

Tutcu, Semra; Serter, Selim; Kaya, Yavuz; Kara, Eray; Nese, Nalan; Pekindil, Goekhan; Coskun, Teoman

2010-01-01

Purpose: It is known that acute pancreatitis may cause secondary changes in several organs. Liver is one of these involved organs. In different experimental studies hepatic damages were shown histopathologically in acute pancreatitis but there are a few studies about perfusion disorders that accompany these histopathologic changes. Perfusion CT (pCT) provides the ability to detect regional and global alterations in organ blood flow. The purpose of the study was to describe hepatic perfusion changes in experimental acute pancreatitis model with pCT. Materials and methods: Forty Sprague-Dawley rats of both genders with average weights of 250 g were used. Rats were randomized into two groups. Twenty rats were in control group and 20 in acute pancreatitis group. pCT was performed. Perfusion maps were formed by processing the obtained images with perfusion CT software. Blood flow (BF) and blood volume (BV) values were obtained from these maps. All pancreatic and liver tissues were taken off with laparotomy and histopathologic investigation was performed. Student's t test was used for statistical analyses. Results: In pCT we found statistically significant increase in blood volume in both lobes of liver and in blood flow in right lobe of the liver (p < 0.01). Although blood flow in left lobe of the liver increased, it did not reach statistical significance. Conclusion: The quantitative analysis of liver parenchyma with pCT showed that acute pancreatitis causes a significant perfusion changes in the hepatic tissue. Systemic mediators seem to be effective as well as local inflammatory changes in perfusion changes.

Hepatic perfusion changes in an experimental model of acute pancreatitis: Evaluation by perfusion CT

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Tutcu, Semra [Department of Surgery, Celal Bayar University, School of Medicine, Manisa (Turkey); Serter, Selim, E-mail: serterselim@gmail.co [Department of Radiology, Celal Bayar University, School of Medicine, Manisa (Turkey); Kaya, Yavuz; Kara, Eray [Department of Surgery, Celal Bayar University, School of Medicine, Manisa (Turkey); Nese, Nalan [Department of Pathology, Celal Bayar University, School of Medicine, Manisa (Turkey); Pekindil, Goekhan [Department of Radiology, Celal Bayar University, School of Medicine, Manisa (Turkey); Coskun, Teoman [Department of Surgery, Celal Bayar University, School of Medicine, Manisa (Turkey)

2010-08-15

Purpose: It is known that acute pancreatitis may cause secondary changes in several organs. Liver is one of these involved organs. In different experimental studies hepatic damages were shown histopathologically in acute pancreatitis but there are a few studies about perfusion disorders that accompany these histopathologic changes. Perfusion CT (pCT) provides the ability to detect regional and global alterations in organ blood flow. The purpose of the study was to describe hepatic perfusion changes in experimental acute pancreatitis model with pCT. Materials and methods: Forty Sprague-Dawley rats of both genders with average weights of 250 g were used. Rats were randomized into two groups. Twenty rats were in control group and 20 in acute pancreatitis group. pCT was performed. Perfusion maps were formed by processing the obtained images with perfusion CT software. Blood flow (BF) and blood volume (BV) values were obtained from these maps. All pancreatic and liver tissues were taken off with laparotomy and histopathologic investigation was performed. Student's t test was used for statistical analyses. Results: In pCT we found statistically significant increase in blood volume in both lobes of liver and in blood flow in right lobe of the liver (p < 0.01). Although blood flow in left lobe of the liver increased, it did not reach statistical significance. Conclusion: The quantitative analysis of liver parenchyma with pCT showed that acute pancreatitis causes a significant perfusion changes in the hepatic tissue. Systemic mediators seem to be effective as well as local inflammatory changes in perfusion changes.

Detection of pulmonary fat embolism with dual-energy CT: an experimental study in rabbits

Energy Technology Data Exchange (ETDEWEB)

Tang, Chun Xiang; Zhou, Chang Sheng; Zhao, Yan E.; Han, Zong Hong; Qi, Li; Zhang, Long Jiang; Lu, Guang Ming [Medical School of Nanjing University, Department of Medical Imaging, Jinling Hospital, Nanjing, Jiangsu (China); Schoepf, U.J. [Medical School of Nanjing University, Department of Medical Imaging, Jinling Hospital, Nanjing, Jiangsu (China); Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); Mangold, Stefanie; Ball, B.D. [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States)

2017-04-15

To evaluate the use of dual-energy CT imaging of the lung perfused blood volume (PBV) for the detection of pulmonary fat embolism (PFE). Dual-energy CT was performed in 24 rabbits before and 1 hour, 1 day, 4 days and 7 days after artificial induction of PFE via the right ear vein. CT pulmonary angiography (CTPA) and lung PBV images were evaluated by two radiologists, who recorded the presence, number, and location of PFE on a per-lobe basis. Sensitivity, specificity, and accuracy of CTPA and lung PBV for detecting PFE were calculated using histopathological evaluation as the reference standard. A total of 144 lung lobes in 24 rabbits were evaluated and 70 fat emboli were detected on histopathological analysis. The overall sensitivity, specificity and accuracy were 25.4 %, 98.6 %, and 62.5 % for CTPA, and 82.6 %, 76.0 %, and 79.2 % for lung PBV. Higher sensitivity (p < 0.001) and accuracy (p < 0.01), but lower specificity (p < 0.001), were found for lung PBV compared with CTPA. Dual-energy CT can detect PFE earlier than CTPA (all p < 0.01). Dual-energy CT provided higher sensitivity and accuracy in the detection of PFE as well as earlier detection compared with conventional CTPA in this animal model study. (orig.)

Mandibular marginal contouring in oriental aesthetic surgery: refined surgical concept and operative procedure.

Science.gov (United States)

Satoh, Kaneshige; Mitsukawa, Nobuyuki

2014-05-01

In aesthetic mandibular contouring surgery, which is often conducted in Asians, the operative procedure is thought to deliver a more aesthetic mandibular shape by means of contouring conducted as a whole from the ramus to the symphysis. The authors describe the refined concept and operative procedures of mandibular marginal contouring. For the 7-year period from 2004 to 2011, mandibular marginal contouring has been used in 57 consecutive series of Japanese subjects. Patient ages ranged from 18 to 33 years, and the subjects included 15 men and 42 women. The surgery was carried out by cutting off the protruding deformed mandibular margin from the ramus to the symphysis. In 53 of 57 cases, the focus was on angle contouring. Concomitant genioplasty by horizontal osteotomy of the chin was conducted in 42 of 57 cases (recession, advancement, shortening, elongation, and correction of the shift variously). In 22 materials exhibiting bulk around the mandibular, the ramus to the body was excised sagittally and thinned. In all the patients, mandibular marginal contouring from the ramus to the symphysis was completed. Partial masseter muscle resection was conducted in 11 of 57 cases. Mandibular contouring effectively achieved a highly satisfactory result in all cases. The upper portion of the peripheral branch of the trunk of the mental nerve was dissected by an electric scalpel in 1 case but sutured immediately using an 8-0 nylon stitch. Transient palsy of the mental nerve was noticed in a few cases but subsided in 1 to 2 months. No particular complications were encountered. No secondary revision was required in this series. In mandibular angle plasty, mandibular marginal contouring from the ramus to the symphysis should be carried out by cutting off the angle keeping in mind the entire mandibular shape. This concept and the procedure can deliver greater patient satisfaction.

Mandibular asymmetry and the fourth dimension.

Science.gov (United States)

Kaban, Leonard B

2009-03-01

This paper represents more than 30 years of discussion and collaboration with Drs Joseph Murray and John Mulliken in an attempt to understand growth patterns over time (ie, fourth dimension) in patients with hemifacial microsomia (HFM). This is essential for the development of rational treatment protocols for children and adults with jaw asymmetry. Traditionally, HFM was thought of as a unilateral deformity, but it was recognized that 20% to 30% of patients had bilateral abnormalities. However, early descriptions of skeletal correction addressed almost exclusively lengthening of the short (affected) side of the face. Based on longitudinal clinical observations of unoperated HFM patients, we hypothesized that abnormal mandibular growth is the earliest skeletal manifestation and that restricted growth of the mandible plays a pivotal role in progressive distortion of both the ipsilateral and contralateral facial skeleton. This hypothesis explains the progressive nature of the asymmetry in patients with HFM and provides the rationale for surgical lengthening of the mandible in children to prevent end-stage deformity. During the past 30 years, we have learned that this phenomenon of progressive distortion of the adjacent and contralateral facial skeleton occurs with other asymmetric mandibular undergrowth (tumor resection, radiation therapy, or posttraumatic defects) and overgrowth (mandibular condylar hyperplasia) conditions. In this paper, I describe the progression of deformity with time in patients with mandibular asymmetry as a result of undergrowth and overgrowth. Understanding these concepts is critical for the development of rational treatment protocols for adults with end-stage asymmetry and for children to minimize secondary deformity.

Thin-plate spline graphical analysis of the mandible in mandibular prognathism.

Science.gov (United States)

Chang, Hsin-Fu; Chang, Hong-Po; Liu, Pao-Hsin; Chang, Chih-Han

2002-11-01

The chin cup has been used to treat skeletal mandibular prognathism in growing patients for 200 years. The pull on the orthopedic-force chin cup is oriented along a line from the mandibular symphysis to the mandibular condyle. Various levels of success have been reported with this restraining device. The vertical chin cup produces strong vertical compression stress on the maxillary molar regions when the direction of traction is 20 degrees more vertical than the chin-condyle line. This treatment strategy may prevent relapse due to counter-clockwise rotation of the mandible. In this report, we describe a new strategy for using chin-cup therapy involving thin-plate spline (TPS) analysis of lateral cephalometric roentgenograms to visualize transformation of the mandible. The actual sites of mandibular skeletal change are not detectable with conventional cephalometric analysis. A case of mandibular prognathism treated with a chin cup and a case of dental Class III malocclusion without orthodontic treatment are described. The case analysis illustrates that specific patterns of mandibular transformation are associated with Class III malocclusion with or without orthopedic therapy, and that visualization of these deformations is feasible using TPS graphical analysis.

Simple Additive Weighting to Diagnose Rabbit Disease

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Ramadiani

2018-01-01

Full Text Available Rabbit is one of the many pets maintained by the general public in Indonesia. Like other pet, rabbits are also susceptible to various diseases. Society in general does not understand correctly the type of rabbit disease and the way of treatment. To help care for sick rabbits it is necessary a decision support system recommendation diagnosis of rabbit disease. The purpose of this research is to make the application of rabbit disease diagnosis system so that can help user in taking care of rabbit. This application diagnoses the disease by tracing the symptoms and calculating the recommendation of the disease using Simple Additive Weighting method. This research produces a web-based decision support system that is used to help rabbit breeders and the general public.

Surgical-prosthetic treatment of large mandibular cysts

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Džambas Ljubiša D.

2003-01-01

Full Text Available This paper presents a combined surgical-prosthetic procedure of reconstructing mandibular bone defect in a 53 year old patient, following enucleation of a mandibular cyst (Cystectomy Partsch II. After a thorough diagnostic evaluation, a surgical procedure was planned with the particular attention to the nature of the disease, patient’s condition, size and extension of the cyst, tissue loss, and the possibilities of prosthetic management of a mandibular bone defect with partial postresection dental prosthesis. It is of great importance to point to the significance of teamwork of a maxillofacial surgeon and a specialist in prosthodontics. This kind of cooperation provided very effective and less risky soft tissue, as well as bone tissue regeneration (osteogenesis. The patient’s recovery was fast, and he could return to his daily activities and work without significant changes regarding quality of life after surgery and prosthetic treatment.

Prospective audit of mandibular fractures at the Charlotte Maxeke ...

African Journals Online (AJOL)

Objective. This study was a prospective cross-sectional clinical audit of patients with mandibular fractures at the Charlotte Maxeke Johannesburg Academic Hospital. Methods. Between 1 March and 31 August 2004, patients with mandibular fractures seen by one clinician had their details recorded. Results. The female:male ...

Na(+)/Ca(2+) exchanger inhibition exerts a positive inotropic effect in the rat heart, but fails to influence the contractility of the rabbit heart.

Science.gov (United States)

Farkas, A S; Acsai, K; Nagy, N; Tóth, A; Fülöp, F; Seprényi, G; Birinyi, P; Nánási, P P; Forster, T; Csanády, M; Papp, J G; Varró, A; Farkas, A

2008-05-01

The Na(+)/Ca(2+) exchanger (NCX) may play a key role in myocardial contractility. The operation of the NCX is affected by the action potential (AP) configuration and the intracellular Na(+) concentration. This study examined the effect of selective NCX inhibition by 0.1, 0.3 and 1.0 microM SEA0400 on the myocardial contractility in the setting of different AP configurations and different intracellular Na(+) concentrations in rabbit and rat hearts. The concentration-dependent effects of SEA0400 on I(Na/Ca) were studied in rat and rabbit ventricular cardiomyocytes using a patch clamp technique. Starling curves were constructed for isolated, Langendorff-perfused rat and rabbit hearts. The cardiac sarcolemmal NCX protein densities of both species were compared by immunohistochemistry. SEA0400 inhibited I(Na/Ca) with similar efficacy in the two species; there was no difference between the inhibitions of the forward or reverse mode of the NCX in either species. SEA0400 increased the systolic and the developed pressure in the rat heart in a concentration-dependent manner, for example, 1.0 microM SEA0400 increased the maximum systolic pressures by 12% relative to the control, whereas it failed to alter the contractility in the rabbit heart. No interspecies difference was found in the cardiac sarcolemmal NCX protein densities. NCX inhibition exerted a positive inotropic effect in the rat heart, but it did not influence the contractility of the rabbit heart. This implies that the AP configuration and the intracellular Na(+) concentration may play an important role in the contractility response to NCX inhibition.

Nuclear medicine and coronary artery disease: evaluation of tracers of myocardial perfusion and vulnerable atherosclerotic plaque

International Nuclear Information System (INIS)

Broisat, A.

2005-04-01

Coronary artery disease is one of the primary cause of mortality worldwide. Nuclear medicine is the major imaging technique for diagnosis and following of this disease. perfusion: nowadays, major radioactive agents used in clinical practice are myocardial perfusion tracers. The reference tracer is thallium-201. However, 201 Tl presents some drawbacks. 99m Tcn-noet has been proposed for its replacement. This study shows that in contrast with previous studies realized in vitro on cardio myocytes, verapamil, an l-type calcium channel inhibitor, does not inhibit myocardial fixation of 99m Tcn-noet in vivo in dog. This data is in agreement with the hypothesis of a non specific endothelial fixation of this tracer. Moreover, this study shows that as a pure tracer of myocardial perfusion, 99m Tcn-noet can also be used to assess myocardial viability on a model of myocardial chronic infarction in rat. atherosclerosis: disruption of vulnerable atherosclerotic plaques is the main event leading to coronary accidents. The second part of this study concerns the evaluation of new potential tracers of the vulnerable atherosclerotic plaque in an experimental model of rabbit with an inheritable hypercholesterolemia. The four tracers evaluated (b2702(r), b2702-I, b2702-Tc and Tc-raft-b2702) are synthetic peptides comprising the residues 75-84 of hla-b2702, a molecule known to link vcam-1, an adhesion molecule expressed in vulnerable atherosclerotic plaque. The autoradiography studies show that all tracers accumulate within atherosclerotic plaque expressing vcam- and that. i-b2702 shows the best plaque/control fixation ratio. (author)

Contralateral thalamic hypoperfusion on brain perfusion SPECT

International Nuclear Information System (INIS)

Lee, Seok Mo; Bae, Sang Kyun; Yoo, Kyung Moo; Yum, Ha Yong

2000-01-01

Brain perfusion single photon emission computed tomography (SPECT) is useful for the localization of cerebrovascular lesion and sometimes reveals more definite lesion than radiologic imaging modality such as CT or MRI does. The purpose of this study was to evaluate the diagnostic usefulness of brain perfusion SPECT in patients with hemisensory impairment. Thirteen consecutive patients (M:F= 8:5, mean age = 48) who has hemisensory impairment were included. Brain perfusion SPECT was performed after intravenous injection of 1110 MBq of Tc-99m ECD. The images were obtained using a dual-head gamma camera with ultra-high resolution collimator. Semiquantitative analysis was performed after placing multiple ROIs on cerebral cortex, basal ganglia, thalamus and cerebellum. There were 10 patients with left hemisensory impairment and 3 patients with right-sided symptom. Only 2 patients revealed abnormal signal change in the thalamus on MRI. But brain perfusion SPECT showed decreased perfusion in the thalamus in 9 patients. Six patients among 10 patients with left hemisensory impairment revealed decreased perfusion in the contralateral thalamus on brain SPECT. The other 4 patients revealed no abnormality. Two patients among 3 patients with right hemisensory impairment also showed decreased perfusion in the contralateral thalamus on brain SPECT. One patients with right hemisensory impairment showed ipsilateral perfusion decrease. Two patients who had follow-up brain perfusion SEPCT after treatment revealed normalization of perfusion in the thalamus. Brain perfusion SPECT might be a useful tool in diagnosing patients with hemisensory impairment

Magnetic resonance perfusion imaging without contrast media

International Nuclear Information System (INIS)

Martirosian, Petros; Graf, Hansjoerg; Schick, Fritz; Boss, Andreas; Schraml, Christina; Schwenzer, Nina F.; Claussen, Claus D.

2010-01-01

Principles of magnetic resonance imaging techniques providing perfusion-related contrast weighting without administration of contrast media are reported and analysed systematically. Especially common approaches to arterial spin labelling (ASL) perfusion imaging allowing quantitative assessment of specific perfusion rates are described in detail. The potential of ASL for perfusion imaging was tested in several types of tissue. After a systematic comparison of technical aspects of continuous and pulsed ASL techniques the standard kinetic model and tissue properties of influence to quantitative measurements of perfusion are reported. For the applications demonstrated in this paper a flow-sensitive alternating inversion recovery (FAIR) ASL perfusion preparation approach followed by true fast imaging with steady precession (true FISP) data recording was developed and implemented on whole-body scanners operating at 0.2, 1.5 and 3 T for quantitative perfusion measurement in various types of tissue. ASL imaging provides a non-invasive tool for assessment of tissue perfusion rates in vivo. Images recorded from kidney, lung, brain, salivary gland and thyroid gland provide a spatial resolution of a few millimetres and sufficient signal to noise ratio in perfusion maps after 2-5 min of examination time. Newly developed ASL techniques provide especially high image quality and quantitative perfusion maps in tissues with relatively high perfusion rates (as also present in many tumours). Averaging of acquisitions and image subtraction procedures are mandatory, leading to the necessity of synchronization of data recording to breathing in abdominal and thoracic organs. (orig.)

Combined surgical management of mandibular angle prominence and microgenia

International Nuclear Information System (INIS)

Portelles Masso, Ayelen Maria; Berger Kohn, Carlos

2010-01-01

Chin play a very important role in facial aesthetics. Different deformities of volume and of position may occur at this level and it is the microgenia one of the more frequent. Treatment options include the use of silicone, alloplasty materials and autologous bone graft. Authors report the use of the bone removed from mandibular angle to increase the chin. This is the case of a white female patient aged 18 seen by the Orthognathics Multidisciplinary Staff of 'V. I. Lenin' Hospital due to its uncommon face width. The corresponding physical examination as well as the complementary ones diagnosed a bilateral prominence of mandibular angle associated with a microgenia. Surgery carried out was of remodeling type of both mandibular angles and genioplasty of height increase and a discrete advancement using the bone removed from the gonion. There were satisfactory aesthetic results without evidence of bone reabsorption. We conclude that use of autologous graft of mandibular angle is an effective treatment alternative for correction of microgenia. (author)

Pharmacologic Effects of Cannabidiol on Acute Reperfused Myocardial Infarction in Rabbits: Evaluated With 3.0T Cardiac Magnetic Resonance Imaging and Histopathology.

Science.gov (United States)

Feng, Yuanbo; Chen, Feng; Yin, Ting; Xia, Qian; Liu, Yewei; Huang, Gang; Zhang, Jian; Oyen, Raymond; Ni, Yicheng

2015-10-01

Cannabidiol (CBD) has anti-inflammatory effects. We explored its therapeutic effects on cardiac ischemia-reperfusion injury with an experimental imaging platform. Reperfused acute myocardial infarction (AMI) was induced in rabbits with a 90-minute coronary artery occlusion followed by 24-hour reperfusion. Before reperfusion, rabbits received 2 intravenous doses of 100 μg/kg CBD (n = 10) or vehicle (control, n = 10). Evans blue was intravenously injected for later detection of the AMI core. Cardiac magnetic resonance imaging was performed to evaluate cardiac morphology and function. After euthanasia, blood troponin I (cTnI) was assessed, and the heart was excised and infused with multifunctional red iodized oil dye. The heart was sliced for digital radiography to quantify the perfusion density rate, area at risk (AAR), and myocardial salvage index, followed by histomorphologic staining. Compared with controls, CBD treatment improved systolic wall thickening (P CBD therapy reduced AMI size and facilitated restoration of left ventricular function. We demonstrated that this experimental platform has potential theragnostic utility.

Hepatic arterial perfusion increases in the early stage of severe acute pancreatitis patients: Evaluation by perfusion computed tomography

International Nuclear Information System (INIS)

Koyasu, Sho; Isoda, Hiroyoshi; Tsuji, Yoshihisa; Yamamoto, Hiroshi; Matsueda, Kazuhiro; Watanabe, Yuji; Chiba, Tsutomu; Togashi, Kaori

2012-01-01

Purpose: Although hepatic perfusion abnormalities have been reported in patients with acute pancreatitis, hepatic perfusion with severe acute pancreatitis (SAP) has not been quantitatively evaluated in humans. Therefore, we investigated hepatic perfusion in patients with SAP using perfusion CT. Materials and methods: Hepatic perfusion CT was performed in 67 patients with SAP within 3 days after symptom onset. The patients were diagnosed as having SAP according to the Atlanta criteria. Fifteen cases were established as a control group. Perfusion CT was obtained for 54 s beginning with a bolus injection of 40 ml of contrast agent (600–630 mgI/kg) at a flow rate of 4 ml/s. Perfusion data were analyzed by the dual-input maximum slope method to obtain hepatic arterial perfusion (HAP) and hepatic portal perfusion (HPP). Finally, we compared HAP and HPP in SAP patients with those in the control group, respectively. Results: Average HAP was significantly higher in SAP patients than in the control group (75.1 ± 38.0 vs. 38.2 ± 9.0 ml/min/100 ml; p < 0.001). There was no significant difference in average HPP between SAP patients and the control group (206.7 ± 54.9 vs. 204.4 ± 38.5 ml/min/100 ml; p = 0.92). Conclusion: Using quantitative analysis on perfusion CT, we first demonstrated an increase of HAP in the right hepatic lobe in SAP patients.

Experimental study on intra-arterial infusion of basic fibroblast growth factor in the ischemic limbs of rabbit model

International Nuclear Information System (INIS)

Zhang Jing; Yang Wenduo

2005-01-01

Objective: To evaluate the effect of intra-arterial infusion of basic fibroblast growth factor (bFGF) on improving neovascularization, vascular perfusion and the function of partially ischemic limbs of rabbits. Methods: Twenty-seven New Zealand male rabbits were selected. Partial ischemia model was induced by surgical ligation of the primary branches of right femoral artery in each animal, and the left hind limb of each animal was served as a nonischemic control. Then, 27 rabbits were randomly assigned to three groups: intra-arterial (IA) infusion of bFGF (n=9), intravenous (IV) infusion of bFGF and IA infusion of saline (n=9). Infusion was separately performed immediately after vascular ligation, 8th and 15th days post-surgery with 10 μg (4 ml) of bFGF per-time (or the same volume of saline). The differences between three groups and between ischemic and nonischemic limbs of the same group were compared and evaluated by the following indexes: (1) vessel section count (VSC), vessel section surface area (VSS) and vessel section perimeter (VSP) in the field of ischemic muscle tissues taken at 22nd day postoperatively; (2) capillary refilling time of ischemic limbs; and (3) functional and trophic changes of ischemic limbs. Statistical differences were evaluated by one-way ANOVA and T test. Results: VSC, VSS and VSP of the IA-bFGF group were significantly increased than those of the IV-bFGF and IA-saline groups (P<0.01). At 22nd day postoperatively, the capillary refilling time, new hair growth, the appearance and function of all ischemic limbs in IA-bFGF group were approximately normal. However, in IA-saline group, the ischemic changes, capillary refilling time and the function of ischemic limbs were not improved significantly. All the indexes of IV-bFGF group showed no difference statistically from those of IA-saline group. Conclusions: This experimental study identifies that intra-arterial infusion of bFGF may significantly promote neovascularization and vascular

Role of sarcoplasmic reticulum calcium in development of secondary calcium rise and early afterdepolarizations in long QT syndrome rabbit model.

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Po-Cheng Chang

Full Text Available L-type calcium current reactivation plays an important role in development of early afterdepolarizations (EADs and torsades de pointes (TdP. Secondary intracellular calcium (Cai rise is associated with initiation of EADs.To test whether inhibition of sarcoplasmic reticulum (SR Ca2+ cycling suppresses secondary Cai rise and genesis of EADs.Langendorff perfusion and dual voltage and Cai optical mapping were conducted in 10 rabbit hearts. Atrioventricular block (AVB was created by radiofrequency ablation. After baseline studies, E4031, SR Ca2+ cycling inhibitors (ryanodine plus thapsigargin and nifedipine were then administrated subsequently, and the protocols were repeated.At baseline, there was no spontaneous or pacing-induced TdP. After E4031 administration, action potential duration (APD was significantly prolonged and the amplitude of secondary Cai rise was enhanced, and 7 (70% rabbits developed spontaneous or pacing-induced TdP. In the presence of ryanodine plus thapsigargin, TdP inducibility was significantly reduced (2 hearts, 20%, p = 0.03. Although APD was significantly prolonged (from 298 ± 30 ms to 457 ± 75 ms at pacing cycle length of 1000 m, p = 0.007 by ryanodine plus thapsigargin, the secondary Cai rise was suppressed (from 8.8 ± 2.6% to 1.2 ± 0.9%, p = 0.02. Nifedipine inhibited TdP inducibility in all rabbit hearts.In this AVB and long QT rabbit model, inhibition of SR Ca2+ cycyling reduces the inducibility of TdP. The mechanism might be suppression of secondary Cai rise and genesis of EADs.

Variant Root Morphology of Third Mandibular Molar in Normal and ...

African Journals Online (AJOL)

isaac kipyator

2017-11-12

Nov 12, 2017 ... ABSTRACT. The mandibular third molar poses a challenge to dental surgeons due to it's unpredictable morphology ... treatment in the School of Dental Sciences since 2010. ... mandibular third molar include presence of three.

Quiste óseo aneurismático mandibular

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Denia Morales Navarro

Full Text Available El quiste óseo aneurismático es definido como una lesión osteolítica expansiva que consiste en espacios llenos de sangre y canales divididos por tabiques de tejido conectivo, los cuales contienen tejido osteoide y células gigantes multinucleadas. El objetivo es presentar un caso clínico poco común de un quiste óseo aneurismático de la región del cuerpo mandibular. Se trata de una paciente femenina de 39 años de edad que acudió a consulta externa del Servicio de Cirugía Maxilofacial del Hospital Universitario "General Calixto García" por aumento de volumen en región mandibular derecha y dolor intenso de 1 mes de evolución. Radiográficamente se detectó un área radiolúcida unilocular de bordes bien definidos; se realizó curetaje de la cavidad, y estudio histopatológico de la lesión que informó la presencia de un quiste óseo aneurismático. Se concluye que el quiste óseo aneurismático es más común en los huesos largos y en la región del ángulo mandibular en el esqueleto facial, por lo que la presentación de este en el cuerpo mandibular resulta de interés.

Mastication markedly affects mandibular condylar cartilage growth, gene expression, and morphology.

Science.gov (United States)

Enomoto, Akiko; Watahiki, Junichi; Nampo, Tomoki; Irie, Tarou; Ichikawa, Yuuta; Tachikawa, Tetsuhiko; Maki, Koutaro

2014-09-01

Mandibular growth is believed to be strongly related to mastication. Furthermore, mandibular condylar cartilage is known to be derived from neural crest cells. We examined whether the degree of chewing affects condylar cartilage growth of the mandible. Mice were fed diets with varying hardness. Genes specific to neural crest-derived cells were measured by real-time polymerase chain reaction to compare the expression changes between the mandibular and tibia cartilages. The mandibular condylar cartilage was then evaluated histologically, and proliferation was evaluated using proliferating cell nuclear antigen. Immunostaining was conducted for osteopontin, type X collagen, and Musashi1, and real-time polymerase chain reaction was used to assess the expression levels of osteopontin and type X collagen. Markers including P75, Wnt-1, Musashi1, and Nestin were upregulated in the mandibular condylar cartilage as compared with the tibial cartilage. Histologic assessment of the mandibular cartilage showed that the hypertrophic chondrocyte zone was statistically significantly thicker in mice fed a hard diet. Chondrocyte proliferation and Musashi1 expression were lower in mice fed a hard diet. After 4 weeks, numerous osteopontin and type X collagen-positive cells were observed in mice fed a mixed diet. Mastication affects the balance between differentiation and proliferation in the mandibular condylar cartilage. This phenomenon might be attributed to the presence of neural crest-derived cells. Copyright © 2014 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

Improved visualization of delayed perfusion in lung MRI

International Nuclear Information System (INIS)

Risse, Frank; Eichinger, Monika; Kauczor, Hans-Ulrich; Semmler, Wolfhard; Puderbach, Michael

2011-01-01

Introduction: The investigation of pulmonary perfusion by three-dimensional (3D) dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) was proposed recently. Subtraction images are generated for clinical evaluation, but temporal information is lost and perfusion defects might therefore be masked in this process. The aim of this study is to demonstrate a simple analysis strategy and classification for 3D-DCE-MRI perfusion datasets in the lung without omitting the temporal information. Materials and methods: Pulmonary perfusion measurements were performed in patients with different lung diseases using a 1.5 T MR-scanner with a time-resolved 3D-GRE pulse sequence. 25 3D-volumes were acquired after iv-injection of 0.1 mmol/kg KG Gadolinium-DTPA. Three parameters were determined for each pixel: (1) peak enhancement S n,max normalized to the arterial input function to detect regions of reduced perfusion; (2) time between arterial peak enhancement in the large pulmonary artery and tissue peak enhancement τ to visualize regions with delayed bolus onset; and (3) ratio R = S n,max /τ was calculated to visualize impaired perfusion, irrespectively of whether related to reduced or delayed perfusion. Results: A manual selection of peak perfusion images is not required. Five different types of perfusion can be found: (1) normal perfusion; (2) delayed non-reduced perfusion; (3) reduced non-delayed perfusion; (4) reduced and delayed perfusion; and (5) no perfusion. Types II and IV could not be seen in subtraction images since the temporal information is necessary for this purpose. Conclusions: The analysis strategy in this study allows for a simple and observer-independent visualization and classification of impaired perfusion in dynamic contrast-enhanced pulmonary perfusion MRI by using the temporal information of the datasets.

Ventilation-perfused studies using SPECT

International Nuclear Information System (INIS)

Zwijnenburg, A.

1989-01-01

A method for the quantitative analysis of ventilation-perfusion SPECT studies is decribed and an effort is made to evaluate its usefullness. The technical details of the emthod are described. In the the transaxial reconstructions of the tomographic studies the contour of the lungs is detected and regional values of lung volume, ventilation, perfusion and ventilation-perfusion ratios are calculated. The method is operator independent. The lung volume calculations from the SPECT studies are validated by comparing them with lung volume measurements using the helium dilution technique. A good correlation (r=0.91) was found between the two volumes. SPECT volume was greater than the volume measured with helium dilution, which was attributed to non-gas-containing structures in the. lungs. The use of ventilation-perfusion ratio SPECT is described to evaluate the effect of ionizing radiation on the lungs in patients treated with mantle field irradiation for Hodgkin's disease. Perfusion changes appear as early as 2 months after the start of irradiation. Ventilation changes appear later and relatively minor. No changes are seen outside the radiation portals. The ventilation-perfusion inequality in pulmonary sarcoidosis is treated. It is suggested that the decrease D LCO in these patients may be partly due to an even distribution of ventilation perfusion ratios. An effort is made to establish the properties of a new tracer used for the assessment of the metabolic function of the pulmonary endothelium. The lung uptake of I-123 IMP mimics the distribution of a perfusion tracer and it is suggested that this tracer may be useful for the early detection of pulmonary vascular damage, even when blood flow is still intact. Some aspects of the use of Kr-81m as a ventilation tracer are discussed as well as the effect of noise on Kr-81m SPECT reconstructions. (author). 146 refs.; 39 figs.; 8 tabs

Automatic assessment of cardiac perfusion MRI

DEFF Research Database (Denmark)

Ólafsdóttir, Hildur; Stegmann, Mikkel Bille; Larsson, Henrik B.W.

2004-01-01

In this paper, a method based on Active Appearance Models (AAM) is applied for automatic registration of myocardial perfusion MRI. A semi-quantitative perfusion assessment of the registered image sequences is presented. This includes the formation of perfusion maps for three parameters; maximum up...

The pathologic mechanisms underlying lumbar distraction spinal cord injury in rabbits.

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Wu, Di; Zheng, Chao; Wu, Ji; Xue, Jing; Huang, Rongrong; Wu, Di; Song, Yueming

2017-11-01

A reliable experimental rabbit model of distraction spinal cord injury (SCI) was established to successfully simulate gradable and replicable distraction SCI. However, further research is needed to elucidate the pathologic mechanisms underlying distraction SCI. The aim of this study was to investigate the pathologic mechanisms underlying lumbar distraction SCI in rabbits. This is an animal laboratory study. Using a self-designed spine distractor, the experimental animals were divided into a control group and 10%, 20%, and 30% distraction groups. Pathologic changes to the spinal cord microvessels in the early stage of distraction SCI were identified by perfusion of the spinal cord vasculature with ink, production of transparent specimens, observation by light microscopy, and observation of corrosion casts of the spinal cord microvascular architecture by scanning electron microscopy. Malondialdehyde (MDA) and superoxide dismutase (SOD) concentrations in the injured spinal cord tissue were measured after 8 hours. With an increasing degree and duration of distraction, the spinal cord microvessels were only partially filled and had the appearance of spasm until rupture and hemorrhage were observed. The MDA concentration increased and the SOD concentration decreased in the spinal cord tissue. Changes to the internal and external spinal cord vessels led to spinal cord ischemia, which is a primary pathologic mechanism of distraction SCI. Lipid peroxidation mediated by free radicals took part in secondary pathologic damage of distraction SCI. Copyright © 2017 Elsevier Inc. All rights reserved.

Can preoperative myocardial perfusion scintigraphy predict changes in left ventricular perfusion and function after coronary artery bypass graft surgery?

DEFF Research Database (Denmark)

Eckardt, Rozy; Kjeldsen, Bo Juel; Johansen, Allan

2012-01-01

OBJECTIVESWe wanted to evaluate whether preoperative myocardial perfusion scintigraphy (MPS) could predict changes in cardiac symptoms and postoperative myocardial perfusion and left ventricular function after coronary artery bypass grafting (CABG).METHODSNinety-two patients with stable angina...... in 26%. Left ventricular ejection fraction (LVEF), which was normal before operation in 45%, improved in 40% of all patients. The increase in LVEF was not related to the preoperative pattern of perfusion defects. Of 30 patients with normalized perfusion after CABG, 29 (97%) had reversible defects...... that reversible or partly reversible perfusion defects at a preoperative MPS have a high chance of normalized myocardial perfusion assessed by MPS 6 months after operation. Normal perfusion is obtained almost exclusively in territories with reversible ischaemia. Symptoms improved in nearly all patients and LVEF...

Coccidian and nematode infections influence prevalence of antibody to myxoma and rabbit hemorrhagic disease viruses in European rabbits.

Science.gov (United States)

Bertó-Moran, Alejandro; Pacios, Isabel; Serrano, Emmanuel; Moreno, Sacramento; Rouco, Carlos

2013-01-01

The interaction among several parasites in European rabbits (Oryctolagus cuniculus) is crucial to host fitness and to the epidemiology of myxomatosis and rabbit hemorrhagic disease. These diseases have caused significant reductions in rabbit populations on the Iberian Peninsula. Most studies have focused on the epidemiology and pathogenesis of these viruses individually, and little is known about interactions between these viruses and other parasites. Taking advantage of an experimental restocking program in Spain, the effects of coccidian and nematode infections on the probability of having detectable antibody to myxoma and rabbit hemorrhagic disease viruses were tested in European wild rabbits. For 14 mo, we monitored rabbit abundance and parasite loads (coccidia and nematodes) in three reintroduced rabbit populations. While coccidian and nematode loads explained seasonal antibody prevalences to myxoma virus, the pattern was less clear for rabbit hemorrhagic disease. Contrary to expectations, prevalence of antibody to myxoma virus was inversely proportional to coccidian load, while nematode load seemed to play a minor role. These results have implications for viral disease epidemiology and for disease management intended to increase rabbit populations in areas where they are important for ecosystem conservation.

Radiographic analysis of odontogenic cysts showing displacement of the mandibular canal

International Nuclear Information System (INIS)

Cho, Bong Hae

2003-01-01

To assess the radiographic findings of odontogenic cysts showing displacement of the mandibular canal using computed tomographic (CT) and panoramic images. CT and panoramic images of 63 odontogenic cysts (27 dentigerous, 16 odontogenic keratocysts, and 20 radicular cysts) were analyzed to evaluate the following parameters: the dimension and shape of the cysts, and the effect of the cysts on the mandibular canal and cortical plates. Of the 63 cysts examined in the study, 35 (55.6%) showed inferior displacement of the mandibular canal and 46 (73.0%) showed perforation of the canal. There were statistically significant differenced between CT and panoramic images in depicting displacement and perforation of the mandibular canal. Cortical expansion was seen in 46 cases (73.0%) and cortical perforation in 23 cases (36.5%). The radicular cysts showed cortical expansion and perforation less frequently than the other cyst groups. Large cysts of mandible should be evaluated by multiplanar CT images in order to detect the mandibular canal and cortical bone involvement.

Ex-vivo machine perfusion for kidney preservation.

Science.gov (United States)

Hamar, Matyas; Selzner, Markus

2018-06-01

Machine perfusion is a novel strategy to decrease preservation injury, improve graft assessment, and increase organ acceptance for transplantation. This review summarizes the current advances in ex-vivo machine-based kidney preservation technologies over the last year. Ex-vivo perfusion technologies, such as hypothermic and normothermic machine perfusion and controlled oxygenated rewarming, have gained high interest in the field of organ preservation. Keeping kidney grafts functionally and metabolically active during the preservation period offers a unique chance for viability assessment, reconditioning, and organ repair. Normothermic ex-vivo kidney perfusion has been recently translated into clinical practice. Preclinical results suggest that prolonged warm perfusion appears superior than a brief end-ischemic reconditioning in terms of renal function and injury. An established standardized protocol for continuous warm perfusion is still not available for human grafts. Ex-vivo machine perfusion represents a superior organ preservation method over static cold storage. There is still an urgent need for the optimization of the perfusion fluid and machine technology and to identify the optimal indication in kidney transplantation. Recent research is focusing on graft assessment and therapeutic strategies.

Deoxycholic Acid and the Marginal Mandibular Nerve: A Cadaver Study.

Science.gov (United States)

Blandford, Alexander D; Ansari, Waseem; Young, Jason M; Maley, Bruce; Plesec, Thomas P; Hwang, Catherine J; Perry, Julian D

2018-06-04

One of the rare but serious complications observed with deoxycholic acid administration is damage to the marginal mandibular nerve. In this study, we evaluated if deoxycholic acid directly induces histologic damage to fresh cadaveric marginal mandibular nerve. A segment of marginal mandibular nerve was harvested from 12 hemifaces of 6 fresh cadavers. The nerve specimen was exposed to either 0.9% sterile saline for 24 h, deoxycholic acid (10 mg/ml) for 20 min, or deoxycholic acid (10 mg/ml) for 24 h. The nerve specimens were then fixed in glutaraldehyde for a minimum of 24 h. Toluidine blue stained sections were evaluated for stain intensity using light microscopy and color deconvolution image analysis. Supraplatysmal fat was harvested as a positive control and exposed to the same treatments as the marginal mandibular nerve specimens, then evaluated using transmission electron microscopy. Toluidine blue staining was less in the marginal mandibular nerve exposed to deoxycholic acid when compared to saline. The specimen exposed to deoxycholic acid for 24 h showed less toluidine blue staining than that of the nerve exposed to deoxycholic acid for 20 min. Transmission electron microscopy of submental fat exposed to deoxycholic acid revealed disruption of adipocyte cell membrane integrity and loss of cellular organelles when compared to specimens only exposed to saline. Deoxycholic acid (10 mg/ml) damages the marginal mandibular nerve myelin sheath in fresh human cadaver specimens. Direct deoxycholic acid neurotoxicity may cause marginal mandibular nerve injury clinically. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Congenitally missing mandibular second premolars: clinical options.

Science.gov (United States)

Kokich, Vincent G; Kokich, Vincent O

2006-10-01

Congenital absence of mandibular second premolars affects many orthodontic patients. The orthodontist must make the proper decision at the appropriate time regarding management of the edentulous space. These spaces can be closed or left open. If the space will be left open for an eventual restoration, the keys during orthodontic treatment are to create the correct amount of space and to leave the alveolar ridge in an ideal condition for a future restoration. If the space will be closed, the clinician must avoid any detrimental alterations to the occlusion and the facial profile. Some early decisions that the orthodontist makes for a patient whose mandibular second premolars are congenitally missing will affect his or her dental health for a lifetime. Therefore, the correct decision must be made at the appropriate time. In this article, we present and discuss various treatment alternatives for managing orthodontic patients with at least 1 congenitally missing mandibular second premolar.

The Psychological Status of Patients with Acute Mandibular Injury

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A. N. Pudov

2012-01-01

Full Text Available Objective: to define the specific features of the psychological status of patients with acute mandibular injury, to compare a psychological reaction to injury in different age groups and in persons with signs of alcohol addiction. Subjects and methods. The study enrolled 37 patients of both sexes over 15 years of age. The patients were distributed by age and chronic alcohol intoxication. Psychological parameters were determined using personality questionnaires: Spielberg-Hanin, Zung, GHQ-28, and Wein ones. Results. The patients with mandibular injury were found to have higher levels of situational and personality anxiety. A state of depression as a response to acute mandibular injury of reactive genesis was found in 29.8% of cases. Autonomic dysfunction occurred in 62.2% of the patients with mandibular fractures. Occult pathopsychological states were detected in 35.1% of the study group patients. Conclusion. The main found peculiarities of the psychological status of the patients with acute mandibular injury were high anxiety and the considerable incidence of autonomic dysfunction syndrome. There were no great age differences in psychological status and the direction of reactions. The patients with chronic alcohol intoxication more frequently developed a depressive state, but the autonomic dysfunction syndrome was just less often encountered and pathopsychological states were less frequently found. Key words: acute low anxiety depression alcohol abuse, psychological status.

Bone changes of mandibular condyle using cone beam computed tomography

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Lee, Ji Un; Kim, Hyung Seop; Song, Ju Seop; Kim, Kyoung A; Koh, Kwang Joon [Chonbuk National Univ., Chonju (Korea, Republic of)

2007-09-15

To assess bone changes of mandibular condyle using cone beam computed tomography (CBCT) in temporomandibualr disorder (TMD) patients. 314 temporomandibular joints (TMJs) images of 163 TMD patients were examined at the Department of Oral and Maxillofacial Radiology, Chonbuk National University. The images were obtained by PSR9000N (Asahi Roentgen Co., Japan) and reconstructed by using Asahivision software (Asahi Roentgen Co., Japan). The CBCT images were examined three times with four weeks interval by three radiologists. Bone changes of mandibular condyle such as flattening, sclerosis, erosion and osteophyte formation were observed in sagittal, axial, coronal and 3 dimensional images of the mandibular condyle. The statistical analysis was performed using SPSS 12.0. Intra-and interobserver agreement were performed by 3 radiologists without the knowledge of clinical information. Osteopathy (2.9%) was found more frequently on anterior surface of the mandibular condyle. Erosion (31.8%) was found more frequently on anterior surface of the mandibular condyle. The intraobserver agreement was good to excellent (k=0.78{sub 0}.84), but interobserver agreement was fair (k=0.45). CBCT can provide high qualified images of bone changes of the TMJ with axial, coronal and 3 dimensional images.

Bone changes of mandibular condyle using cone beam computed tomography

International Nuclear Information System (INIS)

Lee, Ji Un; Kim, Hyung Seop; Song, Ju Seop; Kim, Kyoung A; Koh, Kwang Joon

2007-01-01

To assess bone changes of mandibular condyle using cone beam computed tomography (CBCT) in temporomandibualr disorder (TMD) patients. 314 temporomandibular joints (TMJs) images of 163 TMD patients were examined at the Department of Oral and Maxillofacial Radiology, Chonbuk National University. The images were obtained by PSR9000N (Asahi Roentgen Co., Japan) and reconstructed by using Asahivision software (Asahi Roentgen Co., Japan). The CBCT images were examined three times with four weeks interval by three radiologists. Bone changes of mandibular condyle such as flattening, sclerosis, erosion and osteophyte formation were observed in sagittal, axial, coronal and 3 dimensional images of the mandibular condyle. The statistical analysis was performed using SPSS 12.0. Intra-and interobserver agreement were performed by 3 radiologists without the knowledge of clinical information. Osteopathy (2.9%) was found more frequently on anterior surface of the mandibular condyle. Erosion (31.8%) was found more frequently on anterior surface of the mandibular condyle. The intraobserver agreement was good to excellent (k=0.78 0 .84), but interobserver agreement was fair (k=0.45). CBCT can provide high qualified images of bone changes of the TMJ with axial, coronal and 3 dimensional images

Mandibular incisive canal in relation to periapical surgery

Directory of Open Access Journals (Sweden)

Kani Bilginaylar

2016-01-01

Full Text Available The aim of the present paper is to emphasize the importance of the mandibular interforaminal neurovascular bundle with a case and make a warning to dentists and surgeons during oral and maxillofacial surgeries, such as implant replacement, bone harvesting, genioplasty, open reduction of a mandibular fracture, and cyst enucleations at this region. In this paper, we present a 58-year-old male who referred with pain and a tingling sensation on the left lower lip. After radiographical, extraoral and intraoral examinations, findings indicated the lesion to be a cyst which was related with a periapical lesion of the canine tooth and extracted socket of first premolar tooth. After removal of a cyst, the mandibular incisive nerve was documented which was in relation to cyst cavity.

Prostaglandin synthesis and catabolism in the gastric mucosa: studies in normal rabbits and rabbits immunized with prostaglandin E2

International Nuclear Information System (INIS)

Redfern, J.S.

1988-01-01

Antral and fundic mucosal homogenates obtained from prostaglandin E2-immunized rabbits converted 14C-arachidonic acid to prostaglandin E2, 6-keto prostaglandin F1 alpha, prostaglandin F2 alpha, and prostaglandin D2. Percentage conversion of 14C-arachidonic acid to these prostaglandin products was not significantly different in prostaglandin E2-immunized rabbits compared with control rabbits (thyroglobulin-immunized and unimmunized rabbits combined). Synthesis of 6-keto prostaglandin F1 alpha, prostaglandin E2 and 13,14-dihydro 15-keto prostaglandin E2 from endogenous arachidonic acid after vortex mixing fundic mucosal homogenates was similar in prostaglandin E2 immunized rabbits and control rabbits. Both in prostaglandin E2-immunized rabbits and controls, 3H-prostaglandin E2 was catabolized extensively by the fundic mucosa, whereas 3H-6-keto prostaglandin F1 alpha, 3H-prostaglandin F2 alpha, and 3H-prostaglandin D2 were not catabolized to any appreciable extent. The rate of catabolism of PGs was not significantly different in prostaglandin E2-immunized rabbits and control rabbits, with the exception of prostaglandin F2 alpha which was catabolized slightly more rapidly in prostaglandin E2-immunized rabbits. These results indicate that development of gastric ulcers in prostaglandin E2-immunized rabbits is not associated with an alteration in the capacity of the gastric mucosa to synthesize or catabolize prostaglandins

Dermatophytes in pet Guinea pigs and rabbits.

Science.gov (United States)

Kraemer, A; Mueller, R S; Werckenthin, C; Straubinger, R K; Hein, J

2012-05-25

The frequency of dermatophytes in pet Guinea pigs and rabbits. To determine the frequency and types of dermatophytes in pet Guinea pigs and rabbits. First, 2153 samples collected from pet Guinea pigs (n=1132) and rabbits (n=1021) with suspected dermatophytosis and submitted to three different laboratories for fungal culture were analysed. Subsequently, healthy Guinea pigs and rabbits, animals with skin lesions and with noncutaneous diseases were examined prospectively for dermatophytes. Trichophyton (T.) mentagrophytes was the most common fungal species isolated (91.6% and 72.3% of positive cultures from Guinea pigs (n=431) and rabbits (n=83), respectively). Animals with positive fungal culture did not show any gender predisposition, but affected animals were younger than those with negative fungal culture (PGuinea pigs and 0/140 healthy rabbits. In addition, fungal cultures of Guinea pigs with skin lesions (n=26) and other diseases (n=25) were positive in 7.7% and 8.0% respectively. Samples collected from 17 rabbits with skin lesions and 32 rabbits with noncutaneous disease were all negative in culture. T. mentagrophytes is the most common dermatophyte in pet Guinea pigs and rabbits, asymptomatic carriers are regularly seen in Guinea pigs, but not in rabbits. Copyright © 2011 Elsevier B.V. All rights reserved.

Evidence-Based Advances in Rabbit Medicine.

Science.gov (United States)

Summa, Noémie M; Brandão, João

2017-09-01

Rabbit medicine has been continuously evolving over time with increasing popularity and demand. Tremendous advances have been made in rabbit medicine over the past 5 years, including the use of imaging tools for otitis and dental disease management, the development of laboratory testing for encephalitozoonosis, or determination of prognosis in rabbits. Recent pharmacokinetic studies have been published, providing additional information on commonly used antibiotics and motility-enhancer drugs, as well as benzimidazole toxicosis. This article presents a review of evidence-based advances for liver lobe torsions, thymoma, and dental disease in rabbits and controversial and new future promising areas in rabbit medicine. Copyright © 2017 Elsevier Inc. All rights reserved.

Nuclear medicine and coronary artery disease: evaluation of tracers of myocardial perfusion and vulnerable atherosclerotic plaque; Medecine nucleaire et maladie coronarienne: evaluation de traceurs de la perfusion myocardique et de la plaque d'atherome vulnerable

Energy Technology Data Exchange (ETDEWEB)

Broisat, A

2005-04-15

Coronary artery disease is one of the primary cause of mortality worldwide. Nuclear medicine is the major imaging technique for diagnosis and following of this disease. perfusion: nowadays, major radioactive agents used in clinical practice are myocardial perfusion tracers. The reference tracer is thallium-201. However, {sup 201}Tl presents some drawbacks. {sup 99m}Tcn-noet has been proposed for its replacement. This study shows that in contrast with previous studies realized in vitro on cardio myocytes, verapamil, an l-type calcium channel inhibitor, does not inhibit myocardial fixation of {sup 99m}Tcn-noet in vivo in dog. This data is in agreement with the hypothesis of a non specific endothelial fixation of this tracer. Moreover, this study shows that as a pure tracer of myocardial perfusion, {sup 99m}Tcn-noet can also be used to assess myocardial viability on a model of myocardial chronic infarction in rat. atherosclerosis: disruption of vulnerable atherosclerotic plaques is the main event leading to coronary accidents. The second part of this study concerns the evaluation of new potential tracers of the vulnerable atherosclerotic plaque in an experimental model of rabbit with an inheritable hypercholesterolemia. The four tracers evaluated (b2702(r), b2702-I, b2702-Tc and Tc-raft-b2702) are synthetic peptides comprising the residues 75-84 of hla-b2702, a molecule known to link vcam-1, an adhesion molecule expressed in vulnerable atherosclerotic plaque. The autoradiography studies show that all tracers accumulate within atherosclerotic plaque expressing vcam- and that. i-b2702 shows the best plaque/control fixation ratio. (author)

Is there a difference between hare syphilis and rabbit syphilis? Cross infection experiments between rabbits and hares

NARCIS (Netherlands)

Lumeij, J.T.|info:eu-repo/dai/nl/073286826; Mikalová, L.; Smajs, D.

2013-01-01

Abstract Cross infection of rabbits and hares with Treponema paraluiscuniculi from rabbits and the related microorganism from hares, which was provisionally named "Treponema paraluisleporis", revealed that T. paraluiscuniculi affects rabbits clinically, but only causes seroconversion in hares

Reduced mandibular range of motion in Duchenne Muscular Dystrophy: predictive factors.

Science.gov (United States)

van Bruggen, H W; Van Den Engel-Hoek, L; Steenks, M H; Bronkhorst, E M; Creugers, N H J; de Groot, I J M; Kalaykova, S I

2015-06-01

Patients with Duchenne muscular dystrophy (DMD) experience negative effects upon feeding and oral health. We aimed to determine whether the mandibular range of motion in DMD is impaired and to explore predictive factors for the active maximum mouth opening (aMMO). 23 patients with DMD (mean age 16.7 ± 7.7 years) and 23 controls were assessed using a questionnaire about mandibular function and impairments. All participants underwent a clinical examination of the masticatory system, including measurement of mandibular range of motion and variables related to mandibular movements. In all patients, quantitative ultrasound of the digastric muscle and the geniohyoid muscle and the motor function measure (MFM) scale were performed. The patients were divided into early and late ambulatory stage (AS), early non-ambulatory stage (ENAS) and late non-ambulatory stage (LNAS). All mandibular movements were reduced in the patient group (P < 0.001) compared to the controls. Reduction in the aMMO (<40 mm) was found in 26% of the total patient group. LNAS patients had significantly smaller mandibular movements compared to AS and ENAS (P < 0.05). Multiple linear regression analysis for aMMO revealed a positive correlation with the body height and disease progression, with MFM total score as the strongest independent risk factor (R(2) = 0.71). Mandibular movements in DMD are significantly reduced and become more hampered with loss of motor function, including the sitting position, arm function, and neck and head control. We suggest that measurement of the aMMO becomes a part of routine care of patients with DMD. © 2015 John Wiley & Sons Ltd.

Regenerative approach to bilateral rostral mandibular reconstruction in a case series of dogs

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Boaz eArzi

2015-03-01

Full Text Available Extensive rostral mandibulectomy in dogs typically results in instability of the mandibles that may lead to malocclusion, difficulty in eating and drinking, food prehension, and pain of the temporomandibular joint. Large rostral mandibular defects are challenging to reconstruct due to the complex geometry of this region. In order to restore mandibular continuity and stability following extensive rostral mandibulectomy, we developed a surgical technique using a combination of intraoral and extraoral approaches, a locking titanium plate and a compression resistant matrix (CRM infused with rhBMP-2. Furthermore, surgical planning that consisted of computed tomographic (CT scanning and 3D model printing were utilized. We describe a regenerative surgical technique for immediate or delayed reconstruction of critical-size rostral mandibular defects in 5 dogs. Three dogs had healed with intact gingival covering over the mandibular defect and had immediate return to normal function and occlusion. Two dogs had the complication of focal plate exposure and dehiscence, which was corrected with mucosal flaps and suturing; these dogs have since healed with intact gingival covering over the mandibular defect. Mineralized tissue formation was palpated clinically within 2 weeks and solid bone formation within 3 months. Computed tomography findings at 6 months postoperatively demonstrated that the newly regenerated mandibular bone had increased in mineral volume with evidence of integration between the native bone, new bone and CRM compared to the immediate postoperative CT. We conclude that rostral mandibular reconstruction using a regenerative approach provides an excellent solution for restoring mandibular continuity and preventing mandibular instability in dogs.

Perfusion based cell culture chips

DEFF Research Database (Denmark)

Heiskanen, Arto; Emnéus, Jenny; Dufva, Martin

2010-01-01

Performing cell culture in miniaturized perfusion chambers gives possibilities to experiment with cells under near in vivo like conditions. In contrast to traditional batch cultures, miniaturized perfusion systems provide precise control of medium composition, long term unattended cultures...... and tissue like structuring of the cultures. However, as this chapter illustrates, many issues remain to be identified regarding perfusion cell culture such as design, material choice and how to use these systems before they will be widespread amongst biomedical researchers....

Effects of Ropivacaine and Bupivacaine on Rabbit Myocardial Energetic Metabolism and Mitochondria Oxidation

Institute of Scientific and Technical Information of China (English)

张诗海; 姚尚龙; 李晴

2003-01-01

Summary: To compare the cardiotoxicity induced by ropivacaine and bupivacaine and to investigatethe mechanism of cardiotoxicity, 24 mature New Zealand rabbits were divided randomly into controlgroup (group C), ropivacaine group (group R) and bupivacaine group (group B). Hearts were drawnout rapidly from the anesthetized animals and cardiac perfusion was performed immediately. Ropiva-caine 500 ng/ml (group R) or bupivacaine 500 ng/ml (group B) was added to the perfusion solution.Ventricular myocardial ATP, ADP and AMP were measured with high performance liquid chro-matogram. The ability of myocardial mitochondria oxidation to pyruvate or palmitoylcarnitine wasdetected with Clark electrode. Our results showed that myocardial ATP and ADP decreased signifi-cantly (P＜0. 05) in group R and most significantly (P＜0. 01) in group B as compared with groupC. Myocardial ATP and ADP decreased most significantly (P＜0. 01) in group B as compared withgroup R. The changes of myocardial AMP revealed significant difference among three groups. Thechanges of pyruvate oxidation exibited no significant difference among the three groups. Palmitoyl-carnitine oxidation decreased markedly (P＜0. 05) in group R and most significantly (P＜0. 01) ingroup B as compared with group C. The present study indicated that the inhibition of lipid substrateoxidation may be responsible for the cardiotoxicity induced by bupivacaine and ropivacaine. The car-diotoxicity induced by ropivacaine is far more less than bupivacaine.

Brain Perfusion Changes in Intracerebral Hemorrhage

International Nuclear Information System (INIS)

Mititelu, R.; Mazilu, C.; Ghita, S.; Rimbu, A.; Marinescu, G.; Codorean, I.; Bajenaru, O.

2006-01-01

Full text: Purpose: Despite the latest advances in medical treatment and neuro critical care, patients suffering spontaneous intracerebral hemorrhage (SICH) still have a very poor prognosis, with a greater mortality and larger neurological deficits at the survivors than for ischemic stroke. Many authors have shown that there are many mechanisms involved in the pathology of SICH: edema, ischemia, inflammation, apoptosis. All of these factors are affecting brain tissue surrounding hematoma and are responsible of the progressive neurological deterioration; most of these damages are not revealed by anatomical imaging techniques. The aim of our study was to asses the role of brain perfusion SPECT in demonstrating perfusion changes in SICH patients. Method: 17 SICH pts were studied. All pts underwent same day CT and brain SPECT with 99mTcHMPAO, 24h-5d from onset of stroke. Results: 14/17 pts showed a larger perfusion defect than expected after CT. In 2 pts hematoma diameter was comparable on CT and SPECT; 1pt had quasinormal aspect of SPECT study. In pts with larger defects, SPECT revealed a large cold spot with similar size compared with CT, and a surrounding hypo perfused area. 6/17 pts revealed cortical hyper perfusion adjacent to hypo perfused area and corresponding to a normal-appearing brain tissue on CT. In 3 pts we found crossed cerebellar diaskisis.In 2 pts we found cortical hypo perfused area in the contralateral cortex, with normal appearing brain tissue on CT. Conclusions: Brain perfusion SPECT revealed different types of perfusion changes in the brain tissue surrounding hematoma. These areas contain viable brain tissue that may be a target for future ne uroprotective strategies. Further studies are definitely required to demonstrate prognostic significance of these changes, but we can conclude that brain perfusion SPECT can play an important role in SICH, by early demonstrating functional changes responsible of clinical deterioration, thus allowing prompt

temporomandibular joint cartilage in rabbits affected by drug-induced osteoarthritis

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Krzysztof Kałużyński

2016-02-01

Full Text Available Background: The aims of this study were to assess the anti-degenerative effects of pioglitazone and to compare these effects with those of methylprednisolone and hyaluronic acid on drug-induced osteoarthritis in rabbits’ temporomandibular joint cartilage.Material and Methods: The experiment was conducted on 40 Californian white rabbits. Degenerative changes were induced by intra-articular injections of papain. Subsequently, all of the animals were randomly assigned to one of four groups:1 a control group that received no medications;2 a group treated with 4 intra-articular injections of 2 mg (0.2 ml of hyaluronic acid at weekly intervals;3 a group treated with 4 intra-articular injections of 2 mg (0.1 ml of methylprednisolone at weekly intervals;4 a group administered pioglitazone orally in daily doses of 2 mg/kg of body weight. Four weeks after the beginning of drug administration, the rabbits were sacrificed. Sagittal sections of the intra-articular cartilage (discs and mandibular condyles were stained with hematoxylin and eosin by the PAS technique and with van Gieson’s solution. Histologic examinations, as well as cartilage thickness and number of cell layers measurements, were performed.Results: Histologic assessment in cases of arthritis-associated pathologies revealed that changes occurred most frequently in the control group and least frequently in the pioglitazone group. There were no differences in the histological structures of the intra-articular discs. Cartilage thickness measurements demonstrated the thinnest cartilage in group 2 and the thickest in group 3. Analysis of cell layer numbers showed the most numerous layers in the pioglitazone group and the least in the control group.Conclusion: Pioglitazone and hyaluronic acid showed anti-degenerative properties compared to methylprednisolone in an animal model.

Developing a Benchmarking Process in Perfusion: A Report of the Perfusion Downunder Collaboration

Science.gov (United States)

Baker, Robert A.; Newland, Richard F.; Fenton, Carmel; McDonald, Michael; Willcox, Timothy W.; Merry, Alan F.

2012-01-01

Abstract: Improving and understanding clinical practice is an appropriate goal for the perfusion community. The Perfusion Downunder Collaboration has established a multi-center perfusion focused database aimed at achieving these goals through the development of quantitative quality indicators for clinical improvement through benchmarking. Data were collected using the Perfusion Downunder Collaboration database from procedures performed in eight Australian and New Zealand cardiac centers between March 2007 and February 2011. At the Perfusion Downunder Meeting in 2010, it was agreed by consensus, to report quality indicators (QI) for glucose level, arterial outlet temperature, and pCO2 management during cardiopulmonary bypass. The values chosen for each QI were: blood glucose ≥4 mmol/L and ≤10 mmol/L; arterial outlet temperature ≤37°C; and arterial blood gas pCO2 ≥ 35 and ≤45 mmHg. The QI data were used to derive benchmarks using the Achievable Benchmark of Care (ABC™) methodology to identify the incidence of QIs at the best performing centers. Five thousand four hundred and sixty-five procedures were evaluated to derive QI and benchmark data. The incidence of the blood glucose QI ranged from 37–96% of procedures, with a benchmark value of 90%. The arterial outlet temperature QI occurred in 16–98% of procedures with the benchmark of 94%; while the arterial pCO2 QI occurred in 21–91%, with the benchmark value of 80%. We have derived QIs and benchmark calculations for the management of several key aspects of cardiopulmonary bypass to provide a platform for improving the quality of perfusion practice. PMID:22730861

Mandibular osteosynthesis in a Boa constrictor snake

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Jorge Luiz Costa Castro

2014-02-01

Full Text Available Nowadays are observed an increase in the finding of certain wild animals in urban areas, due to environmental changes caused by deforestation and economic use of natural areas. It causes disappearance of usual prey and forces these animals, including snakes, to migrate to urban areas, becoming vulnerable to injuries caused by aggressions, car accidents and capture. Mandibular and maxillar fractures are common in many animal species, representing about 3-6% of all bone fractures in dogs and cats. Mandibular trauma usually occurs as a result of fights, car accidents and improper handling and/or restraint, and fractures can be closed or open, clean or contaminated. The jaw is a flat bone with differences from the long bones that should be taken into consideration for successful treatment, being minimal muscle coverage and need to maintain occlusion factors that influence the definition of the best ostheosynthesis method. The methods of stabilization include using intramedullary pins, wires, external skeletal fixation, bone plate, and acrylic resin. Conventional bone plates are efficient but related to some complications, such as the necessity of muscular elevation and high risk of injuries to mandibular structures. This article describes the successful results of the application of plate and screws in the ostheosynthesis of a mandibular fracture in a female Boa constrictor snake with weight of 8.0 kg and length of 1.80 m, at the RIOZOO Foundation (Rio de Janeiro, RJ, Brazil.

Physiologic characterization of inflammatory arthritis in a rabbit model with BOLD and DCE MRI at 1.5 Tesla

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Nasui, Otilia C.; Chan, Michael W.; Nathanael, George; Rayner, Tammy; Weiss, Ruth; Detzler, Garry; Zhong, Anguo [The Hospital for Sick Children, Department of Diagnostic Imaging, Toronto, ON (Canada); Crawley, Adrian [University of Toronto, Department of Medical Imaging, Toronto, ON (Canada); Toronto Western Hospital, Department of Medical Imaging, Toronto, ON (Canada); Miller, Elka [Children' s Hospital of Eastern Ontario (CHEO), Department of Diagnostic Imaging, Ottawa, ON (Canada); Belik, Jaques [The Hospital for Sick Children, Department of Neonatology, Toronto, ON (Canada); Cheng, Hai-Ling; Kassner, Andrea; Doria, Andrea S. [The Hospital for Sick Children, Department of Diagnostic Imaging, Toronto, ON (Canada); University of Toronto, Department of Medical Imaging, Toronto, ON (Canada); Moineddin, Rahim [Department of Public Health, Family and Community Medicine, Toronto, ON (Canada); Jong, Roland; Rogers, Marianne [Mount Sinai Hospital, Department of Pathology, Toronto, ON (Canada)

2014-11-15

Our aim was to test the feasibility of blood oxygen level dependent magnetic resonance imaging (BOLD MRI) and dynamic contrast-enhanced (DCE) MRI to monitor periarticular hypoxic/inflammatory changes over time in a juvenile rabbit model of arthritis. We examined arthritic and contralateral nonarthritic knees of 21 juvenile rabbits at baseline and days 1,14, and 28 after induction of arthritis by unilateral intra-articular injection of carrageenin with BOLD and DCE MRI at 1.5 Tesla (T). Nine noninjected rabbits served as controls. Associations between BOLD and DCE-MRI and corresponding intra-articular oxygen pressure (PO{sub 2}) and blood flow [blood perfusion units (BPU)] (polarographic probes, reference standards) or clinical-histological data were measured by correlation coefficients. Percentage BOLD MRI change obtained in contralateral knees correlated moderately with BPU on day 0 (r = -0.51, p = 0.02) and excellently on day 28 (r = -0.84, p = 0.03). A moderate correlation was observed between peak enhancement DCE MRI (day 1) and BPU measurements in arthritic knees (r = 0.49, p = 0.04). In acute arthritis, BOLD and DCE MRI highly correlated (r = 0.89, p = 0.04; r = 1.0, p < 0.0001) with histological scores in arthritic knees. The proposed techniques are feasible to perform at 1.5 T, and they hold potential as surrogate measures to monitor hypoxic and inflammatory changes over time in arthritis at higher-strength MRI fields. (orig.)

Mandibular second molar with 3 mesial canals and a radix paramolaris

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N Ragavendran

2014-01-01

Full Text Available Mandibular first molar commonly has two roots, the mesial and the distal root. Surprisingly in some mandibular first molar has an unusual extra third root in between mesial and distal root. This extra root is the most commonly seen in lingual side and is called as radix entomolaris. If this extra root is seen on the buccal side, it is termed as radix paramolaris (RP, which is a very rare phenomenon. Recently, various case report studies has shown the presence of third canal in the mesial and distal roots of mandibular molars. They are named as middle mesial and middle distal canal, respectively. Here, we present a case report of mandibular second molar showing three canals in the mesial root and a RP.

Restricted Mandibular Movement Attributed to Ossification of Mandibular Depressors and Medial Pterygoid Muscles in Patients With Fibrodysplasia Ossificans Progressiva: A Report of 3 Cases.

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Okuno, Tetsuko; Suzuki, Hitoshi; Inoue, Akio; Kusukawa, Jingo

2017-09-01

Fibrodysplasia ossificans progressiva (FOP) is an extremely rare genetic condition characterized by congenital malformation and progressive heterotopic ossification (HO) caused by a recurrent single nucleotide substitution at position 617 in the ACVR1 gene. As the condition progresses, HO leads to joint ankylosis, breathing difficulties, and mouth-opening restriction, and it can shorten the patient's lifespan. This report describes 3 cases of FOP confirmed by genetic testing in patients with restricted mouth opening. Each patient presented a different onset and degree of jaw movement restriction. The anatomic ossification site of the mandibular joint was examined in each patient using reconstructed computed tomographic (CT) images and 3-dimensional reconstructed CT (3D-CT) images. A 29-year-old woman complained of jaw movement restriction since 13 years of age. 3D-CT image of the mandibular joint showed an osseous bridge, formed by the mandibular depressors that open the mouth, between the hyoid bone and the mentum of the mandible. A 39-year-old man presented with jaw movement restriction that developed at 3 years of age after a mouth injury. 3D-CT image of the jaw showed ankylosis of the jaw from ossification of the mandibular depressors that was worse than in patient 1. CT images showed no HO findings of the masticatory muscles. To the authors' knowledge, these are the first 2 case descriptions of the anatomic site of ankylosis involving HO of the mandibular depressors in the jaw resulting from FOP. In contrast, a 62-year-old bedridden woman with an interincisal distance longer than 10 mm (onset, 39 years of age) had no HO of the mandibular depressors and slight HO of the medial pterygoid muscle on the right and left sides. These findings suggest that restricted mouth opening varies according to the presence or absence of HO of the mandibular depressors. Copyright © 2017. Published by Elsevier Inc.

Non-contrast MRI perfusion angiosome in diabetic feet

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Zheng, Jie [Cardiovascular Imaging Lab, Mallinckrodt Institute of Radiology, St. Louis, MO (United States); Hastings, Mary K.; Mueller, Michael J. [Washington University School of Medicine, The Program in Physical Therapy, St. Louis, MO (United States); Muccigross, David; Hildebolt, Charles F. [Washington University School of Medicine, Mallinckrodt Institute of Radiology, St. Louis, MO (United States); Fan, Zhaoyang [Cedars-Sinai Medical Center, Biomedical Imaging Research Institute, Los Angeles, CA (United States); Gao, Fabao [West China Hospital, Sichuan University, Department of Radiology, Chengdu (China); Curci, John [Washington University School of Medicine, The Department of Surgery, St. Louis, MO (United States)

2015-01-15

The purpose of this study is to develop a non-contrast magnetic resonance imaging (MRI) approach to evaluate skeletal muscle perfusion in the diabetic foot based on the concept of angiosomes of the foot. Five healthy volunteers and five participants with diabetes (HbA1c = 7.2 ± 1.8 %) without a history of peripheral artery disease were examined. The non-contrast perfusion measurements were performed during a toe flexion challenge. Absolute perfusion maps were created and two regions (medial and lateral) on the maps were segmented based on angiosomes. Regional difference in the perfusion of foot muscle was readily visualized in the MRI perfusion angiosomes during the challenge. In the participants with diabetes, the perfusion during toe flexion challenge was significantly lower than in healthy volunteers (P < 0.01). The average perfusion for the medial plantar region of the right foot was lower in subjects with diabetes (38 ± 9 ml/min/100 g) than in healthy subjects (93 ± 33 ml/min/100 g). Non-contrast MRI perfusion angiosome maps demonstrate the feasibility of determining regional perfusion in foot muscles during toe challenge and may facilitate evaluation of muscle perfusion in diabetic feet. (orig.)

Non-contrast MRI perfusion angiosome in diabetic feet

International Nuclear Information System (INIS)

Zheng, Jie; Hastings, Mary K.; Mueller, Michael J.; Muccigross, David; Hildebolt, Charles F.; Fan, Zhaoyang; Gao, Fabao; Curci, John

2015-01-01

The purpose of this study is to develop a non-contrast magnetic resonance imaging (MRI) approach to evaluate skeletal muscle perfusion in the diabetic foot based on the concept of angiosomes of the foot. Five healthy volunteers and five participants with diabetes (HbA1c = 7.2 ± 1.8 %) without a history of peripheral artery disease were examined. The non-contrast perfusion measurements were performed during a toe flexion challenge. Absolute perfusion maps were created and two regions (medial and lateral) on the maps were segmented based on angiosomes. Regional difference in the perfusion of foot muscle was readily visualized in the MRI perfusion angiosomes during the challenge. In the participants with diabetes, the perfusion during toe flexion challenge was significantly lower than in healthy volunteers (P < 0.01). The average perfusion for the medial plantar region of the right foot was lower in subjects with diabetes (38 ± 9 ml/min/100 g) than in healthy subjects (93 ± 33 ml/min/100 g). Non-contrast MRI perfusion angiosome maps demonstrate the feasibility of determining regional perfusion in foot muscles during toe challenge and may facilitate evaluation of muscle perfusion in diabetic feet. (orig.)

A correlational study of scoliosis and trunk balance in adult patients with mandibular deviation.

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Shuncheng Zhou

Full Text Available Previous studies have confirmed that patients with mandibular deviation often have abnormal morphology of their cervical vertebrae. However, the relationship between mandibular deviation, scoliosis, and trunk balance has not been studied. Currently, mandibular deviation is usually treated as a single pathology, which leads to poor clinical efficiency. We investigated the relationship of spine coronal morphology and trunk balance in adult patients with mandibular deviation, and compared the finding to those in healthy volunteers. 35 adult patients with skeletal mandibular deviation and 10 healthy volunteers underwent anterior X-ray films of the head and posteroanterior X-ray films of the spine. Landmarks and lines were drawn and measured on these films. The axis distance method was used to measure the degree of scoliosis and the balance angle method was used to measure trunk balance. The relationship of mandibular deviation, spine coronal morphology and trunk balance was evaluated with the Pearson correlation method. The spine coronal morphology of patients with mandibular deviation demonstrated an "S" type curve, while a straight line parallel with the gravity line was found in the control group (significant difference, p1°, while the control group had a normal trunk balance (imbalance angle <1°. There was a significant difference between the two groups (p<0.01. The degree of scoliosis and shoulder imbalance correlated with the degree of mandibular deviation, and presented a linear trend. The direction of mandibular deviation was the same as that of the lateral bending of thoracolumbar vertebrae, which was opposite to the direction of lateral bending of cervical vertebrae. Our study shows the degree of mandibular deviation has a high correlation with the degree of scoliosis and trunk imbalance, all the three deformities should be clinically evaluated in the management of mandibular deviation.

Detection and localization of rabbit hepatitis e virus and antigen in systemic tissues from experimentally intraperitoneally infected rabbits.

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Jingjing Mao

Full Text Available Rabbit hepatitis E virus (HEV is a novel genotype of HEV, and is considered to pose a risk of zoonotic transmission. Research into the systemic distribution of rabbit HEV in rabbits during different periods of infection has rarely been reported. To better understand this virus, we infected rabbits with second-passage rabbit HEV via an intraperitoneal route. After inoculation, the infection showed two types, temporary and constant infection. The detection of HEV RNA in the feces varied with time, and serum antigen correlated with fecal HEV RNA. Viremia only appeared 72 days after inoculation. The rabbits remained antibody negative throughout the experimental period. When HEV was localized, several organs besides the liver were HEV RNA positive. Tissue antigen was observed immunohistochemically in the different cells of various organs, especially in parts of the small intestine and the characteristic rabbit gut-associated lymphoid tissue. These data provide valuable information for future research into the pathogenesis of HEV.

Dual-energy perfusion-CT of pancreatic adenocarcinoma

International Nuclear Information System (INIS)

Klauß, M.; Stiller, W.; Pahn, G.; Fritz, F.; Kieser, M.; Werner, J.; Kauczor, H.U.; Grenacher, L.

2013-01-01

Purpose: To evaluate the feasibility of dual-energy CT (DECT)-perfusion of pancreatic carcinomas for assessing the differences in perfusion, permeability and blood volume of healthy pancreatic tissue and histopathologically confirmed solid pancreatic carcinoma. Materials and methods: 24 patients with histologically proven pancreatic carcinoma were examined prospectively with a 64-slice dual source CT using a dynamic sequence of 34 dual-energy (DE) acquisitions every 1.5 s (80 ml of iodinated contrast material, 370 mg/ml, flow rate 5 ml/s). 80 kV p , 140 kV p , and weighted average (linearly blended M0.3) 120 kV p -equivalent dual-energy perfusion image data sets were evaluated with a body-perfusion CT tool (Body-PCT, Siemens Medical Solutions, Erlangen, Germany) for estimating perfusion, permeability, and blood volume values. Color-coded parameter maps were generated. Results: In all 24 patients dual-energy CT-perfusion was. All carcinomas could be identified in the color-coded perfusion maps. Calculated perfusion, permeability and blood volume values were significantly lower in pancreatic carcinomas compared to healthy pancreatic tissue. Weighted average 120 kV p -equivalent perfusion-, permeability- and blood volume-values determined from DE image data were 0.27 ± 0.04 min −1 vs. 0.91 ± 0.04 min −1 (p −1 vs. 0.67 ± 0.05 *0.5 min −1 (p = 0.06) and 0.49 ± 0.07 min −1 vs. 1.28 ± 0.11 min −1 (p p the standard deviations of the kV p 120 kV p -equivalent values were manifestly smaller. Conclusion: Dual-energy CT-perfusion of the pancreas is feasible. The use of DECT improves the accuracy of CT-perfusion of the pancreas by fully exploiting the advantages of enhanced iodine contrast at 80 kV p in combination with the noise reduction at 140 kV p . Therefore using dual-energy perfusion data could improve the delineation of pancreatic carcinomas

Mandibular ramus: A predictor for sex determination - A digital radiographic study

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Kotya Naik Maloth

2017-01-01

Full Text Available Aim: To evaluate mandibular ramus linear measurements on digital panoramic radiographs and to assess the usefulness of mandibular ramus in sex determination. Material and Methods: A retrospective study was conducted on 100 patients (50 males and 50 females using digital panoramic radiographs of Khammam population with age ranging from 20 to 50 years. Standard digital panoramic radiographs were taken without any errors by Sirona, ORTHOPHOS XG 5 machine. The following five mandibular linear measurements were performed in cm such as upper ramus breadth, lower ramus breadth, condylar ramus height, projective ramus height, and coronoid ramus height. The obtained data were analyzed with the software SPSS 13.0 for statistical analysis using discriminate methods. Results: In the present study, all the linear measurements of mandibular ramus on digital panoramic radiographs showed a statistically significant difference between the genders. Conclusion: We conclude that the use of mandibular ramus is recommended as an aid for sex determination in forensic science due to their unique feature of sexual dimorphism.

Clinical importance of median mandibular flexure in oral rehabilitation: a review.

Science.gov (United States)

Sivaraman, K; Chopra, A; Venkatesh, S B

2016-03-01

The mandible has a property to flex inwards around the mandibular symphysis with change in shape and decrease in mandibular arch width during opening and protrusion of the mandible. The mandibular deformation may range from a few micrometres to more than 1 mm. The movement occurs because of the contraction of lateral pterygoid muscles that pulls mandibular condyles medially and causes a sagittal movement of the posterior segments. This movement of mandible can have a profound influence on prognosis and treatment outcome for various restorative, endodontics, fixed, removable and implant-related prosthesis. The review unfolds the causes, importance and clinical implications of median mandibular flexure in oral rehabilitation. This review also highlights the appropriate preventive measures and techniques that should be adopted by clinicians to minimise the effect of flexural movement of the jaw during oral rehabilitation. This would not only help clinicians to achieve a good prosthesis with accurate fit and longevity but also maintain the health of the surrounding periodontal or periimplant gingival tissues and bone. © 2015 John Wiley & Sons Ltd.

Mandibular growth changes and cervical vertebral maturation. a cephalometric implant study.

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Gu, Yan; McNamara, James A

2007-11-01

To evaluate mandibular dimensional changes and regional remodeling occurring during five intervals of circumpubertal growth. This investigation evaluated a unique sample of subjects in whom tantalum implants were placed into the craniofacial complex during childhood. The sample was obtained from the Mathews and Ware implant study originally conducted at the University of California San Francisco in the 1970s, with longitudinal cephalometric records of 20 subjects (13 female, 7 male) available for evaluation. Cephalograms at six consecutive stages of cervical vertebral maturation (CS1 through CS6) were analyzed. Peak mandibular growth was noted during the interval from CS3 to CS4. Forward rotation of the mandible was due to greater mandibular growth posteriorly than anteriorly. Progressive closure of the condylar-ramus-occlusal (CRO) angle resulted in a forward and upward orientation of the ramus relative to the corpus of the mandible due to increased vertical growth of the condyle. A peak in mandibular growth at puberty was substantiated. Mandibular remodeling and condylar rotation continue to occur after the growth spurt.

Nuclear medicine and coronary artery disease: evaluation of tracers of myocardial perfusion and vulnerable atherosclerotic plaque; Medecine nucleaire et maladie coronarienne: evaluation de traceurs de la perfusion myocardique et de la plaque d'atherome vulnerable

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Broisat, A

2005-04-15

Coronary artery disease is one of the primary cause of mortality worldwide. Nuclear medicine is the major imaging technique for diagnosis and following of this disease. perfusion: nowadays, major radioactive agents used in clinical practice are myocardial perfusion tracers. The reference tracer is thallium-201. However, {sup 201}Tl presents some drawbacks. {sup 99m}Tcn-noet has been proposed for its replacement. This study shows that in contrast with previous studies realized in vitro on cardio myocytes, verapamil, an l-type calcium channel inhibitor, does not inhibit myocardial fixation of {sup 99m}Tcn-noet in vivo in dog. This data is in agreement with the hypothesis of a non specific endothelial fixation of this tracer. Moreover, this study shows that as a pure tracer of myocardial perfusion, {sup 99m}Tcn-noet can also be used to assess myocardial viability on a model of myocardial chronic infarction in rat. atherosclerosis: disruption of vulnerable atherosclerotic plaques is the main event leading to coronary accidents. The second part of this study concerns the evaluation of new potential tracers of the vulnerable atherosclerotic plaque in an experimental model of rabbit with an inheritable hypercholesterolemia. The four tracers evaluated (b2702(r), b2702-I, b2702-Tc and Tc-raft-b2702) are synthetic peptides comprising the residues 75-84 of hla-b2702, a molecule known to link vcam-1, an adhesion molecule expressed in vulnerable atherosclerotic plaque. The autoradiography studies show that all tracers accumulate within atherosclerotic plaque expressing vcam- and that. i-b2702 shows the best plaque/control fixation ratio. (author)

Rabbit haemorrhagic disease: are Australian rabbits (Oryctolagus cuniculus) evolving resistance to infection with Czech CAPM 351 RHDV?

Science.gov (United States)

Elsworth, P G; Kovaliski, J; Cooke, B D

2012-11-01

Rabbit haemorrhagic disease is a major tool for the management of introduced, wild rabbits in Australia. However, new evidence suggests that rabbits may be developing resistance to the disease. Rabbits sourced from wild populations in central and southeastern Australia, and domestic rabbits for comparison, were experimentally challenged with a low 60 ID50 oral dose of commercially available Czech CAPM 351 virus - the original strain released in Australia. Levels of resistance to infection were generally higher than for unselected domestic rabbits and also differed (0-73% infection rates) between wild populations. Resistance was lower in populations from cooler, wetter regions and also low in arid regions with the highest resistance seen within zones of moderate rainfall. These findings suggest the external influences of non-pathogenic calicivirus in cooler, wetter areas and poor recruitment in arid populations may influence the development rate of resistance in Australia.

[Congenital malformations of the temporo-mandibular joint and the mandibular ramus: Grafting vs distraction osteogenesis].

Science.gov (United States)

Gallucci, A; Graillon, N; Foletti, J M; Chossegros, C; Cheynet, F

2016-09-01

Congenital deformities of the mandibular ramus and of the temporo-mandibular joint are treated by surgery since the early 20th century. However, morphological and functional results are often disappointing, accounting for iterative operations. Today, a clear consensus concerning the type of intervention to be proposed, and at what age it should be carried out does not yet exist. For mild cases, "conventional" orthognathic or osteogenic distraction procedures seem to work well, especially if they are carried out at the end of growth. In severe cases, it is often necessary to proceed in several surgical steps, usually starting with a chondrocostal graft, especially when interceptive surgery, performed before the end of growth, is preferred in order to improve the patient's quality of life. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Lower molar and incisor displacement associated with mandibular remodeling.

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Baumrind, S; Bravo, L A; Ben-Bassat, Y; Curry, S; Korn, E L

1997-01-01

The purpose of this study was to quantify the amount of alveolar modeling at the apices of the mandibular incisor and first molar specifically associated with appositional and resorptive changes on the lower border of the mandible during growth and treatment. Cephalometric data from superimpositions on anterior cranial base, mandibular implants of the Björk type, and anatomical "best fit" of mandibular border structures were integrated using a recently developed strategy, which is described. Data were available at annual intervals between 8.5 and 15.5 years for a previously described sample of approximately 30 children with implants. The average magnitudes of the changes at the root apices of the mandibular first molar and central incisor associated with modeling/remodeling of the mandibular border and symphysis were unexpectedly small. At the molar apex, mean values approximated zero in both anteroposterior and vertical directions. At the incisor apex, mean values approximated zero in the anteroposterior direction and averaged less than 0.15 mm/year in the vertical direction. Standard deviations were roughly equal for the molar and the incisor in both the anteroposterior and vertical directions. Dental displacement associated with surface modeling plays a smaller role in final tooth position in the mandible than in the maxilla. It may also be reasonably inferred that anatomical best-fit superimpositions made in the absence of implants give a more complete picture of hard tissue turnover in the mandible than they do in the maxilla.

Peripheral Osteoma of the Mandibular Notch: Report of a Case

International Nuclear Information System (INIS)

Iwai, Toshinori; Izumi, Toshiharu; Baba, Junichi; Maegawa, Jiro; Mitsudo, Kenji; Tohnai, Iwai

2013-01-01

Osteoma is a benign, slow-growing osteogenic tumor that sometimes arises from the craniomaxillofacial region, such as the sinus, temporal or jaw bones. Osteoma consists of compact or cancellous bone that may be peripheral, central or extraskeletal type. Peripheral osteoma arises from the periosteum and is commonly a unilateral, pedunculated mushroom-like mass. Peripheral osteoma of the mandible is relatively uncommon, and peripheral osteoma of the mandibular notch is extremely rare, although many cases arise from the mandibular body, angle, condyle, or coronoid process. We report here an unusual peripheral osteoma of the mandibular notch in a 78-year-old nonsyndromic female

In-vivo quantitative evaluation of perfusion zones and perfusion gradient in the deep inferior epigastric artery perforator flap

Science.gov (United States)

Saint-Cyr, Michel; Lakhiani, Chrisovalantis; Cheng, Angela; Mangum, Michael; Liang, Jinyang; Teotia, Sumeet; Livingston, Edward H.; Zuzak, Karel J.

2013-03-01

The selection of well-vascularized tissue during DIEP flap harvest remains controversial. While several studies have elucidated cross-midline perfusion, further characterization of perfusion to the ipsilateral hemiabdomen is necessary for minimizing rates of fat necrosis or partial fat necrosis in bilateral DIEP flaps. Eighteen patients (29 flaps) underwent DIEP flap harvest using a prospectively designed protocol. Perforators were marked and imaged with a novel system for quantitatively measuring tissue oxygenation, the Digital Light Hyperspectral Imager. Images were then analyzed to determine if perforator selection influenced ipsilateral flap perfusion. Flaps based on a single lateral row perforator (SLRP) were found to have a higher level of hemoglobin oxygenation in Zone I (mean %HbO2 = 76.1) compared to single medial row perforator (SMRP) flaps (%HbO2 = 71.6). Perfusion of Zone III relative to Zone I was similar between SLRP and SMRP flaps (97.4% vs. 97.9%, respectively). These differences were not statistically significant (p>0.05). Perfusion to the lateral edge of the flap was slightly greater for SLRP flaps compared SMRP flaps (92.1% vs. 89.5%, respectively). SMRP flaps had superior perfusion travelling inferiorly compared to SLRP flaps (88.8% vs. 83.9%, respectively). Overall, it was observed that flaps were better perfused in the lateral direction than inferiorly. Significant differences in perfusion gradients directed inferiorly or laterally were observed, and perforator selection influenced perfusion in the most distal or inferior aspects of the flap. This suggests broader clinical implications for flap design that merit further investigation.

Perfusion vector - a new method to quantify myocardial perfusion scintigraphy images: a simulation study with validation in patients

DEFF Research Database (Denmark)

Minarik, David; Senneby, Martin; Wollmer, Per

2015-01-01

Background The interpretation of myocardial perfusion scintigraphy (MPS) largely relies on visual assessment by the physician of the localization and extent of a perfusion defect. The aim of this study was to introduce the concept of the perfusion vector as a new objective quantitative method...

Placental perfusion - a human alternative

DEFF Research Database (Denmark)

Mose, Tina; Knudsen, Lisbeth E

2006-01-01

Foetal exposures to environmental and medicinal products have impact on the growth of the foetus (e.g. cigarette smoke) and development of organs (e.g. methylmercury and Thalidomide). Perfusion studies of the human term placenta enable investigation of placental transport of chemical substances...... between the mother and foetus. Dual perfusion of a single cotyledon in the human placenta can contribute to a better understanding of the placental barrier, transport rate and mechanisms of different substances and placental metabolism. The perfusion system has recently been established in Copenhagen...

Rabbit haemorrhagic disease: advantages of cELISA in assessing immunity in wild rabbits (Oryctolagus cuniculus).

Science.gov (United States)

Zheng, Tao; Parkes, John P

2011-12-15

Rabbit haemorrhagic disease (RHD) is an acute fatal disease of domestic and wild European rabbits (Oryctolagus cuniculus) caused by RHD virus (RHDV). Accurate assessment of immunity is of great importance for the conservation and control of wild rabbits. We evaluated a competitive ELISA (cELISA) against isotype ELISAs for assessing the protective immunity against the disease by challenging 50 wild-caught rabbits with a lethal dose of RHDV. Death or survival to the challenge was used as a criterion to determine the performance characteristics of the assay for the assessment of immunity in rabbits. At 1:10 dilution, a serum exhibiting ≥ 25% inhibition (1:10(25)) was regarded as the presence of RHDV-specific antibodies. Eleven of 16 (68.8%) rabbits with antibodies at 1:10(25) (<1:40) died of RHD. When the cut-off was moved from 25% to 50% inhibition (1:10(50)) at 1:10 serum dilution, the assay sensitivity, specificity and accuracy for the protective immunity were improved from 84%, 54.2% and 69.4% to 84%, 100% and 91.8%, respectively. We also demonstrated at the epitope amino acid sequence level why the presence of the RHDV-cross reactive benign rabbit calicivirus, which interfered with isotype ELISAs, had little impact on the specificity of the cELISA for the diagnosis of RHDV infection. The presence of RHDV-specific antibody at 1:10(50) by the cELISA is a reliable indicator for the protective immunity. In contrast to isotype ELISAs, the cELISA is a valuable specific tool for monitoring the herd immunity to RHD for the conservation and management of wild rabbits in the field. Copyright © 2011 Elsevier B.V. All rights reserved.

High rabbit abundance proves detrimental to the population growth rate in European rabbit (Oryctolagus cuniculus L. extensive breeding enclosures

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L. Ruiz-Aizpurua

2014-09-01

Full Text Available The European rabbit (Oryctolagus cuniculus L. is a key prey species in Mediterranean ecosystems that has declined in its natural ranges as a result of diseases and loss of habitat. This situation has led to the production of wild rabbits in enclosures in which they can acclimate and breed. The efficiency of these enclosures as extensive breeding systems is defined by their population growth rate (PGR. The aim of this study is to analyse the effect of rabbit abundance on the PGR. This has been done by creating general linear models to explain autumn and spring PGR with the use of rabbit abundance estimates, enclosure size, aerial predation and previous PGR as possible explanatory variables. Rabbit abundance and enclosure size negatively affected the autumn PGR, while only rabbit abundance affected the spring PGR in the best-fit models. It is suggested that maintaining rabbit densities at fewer than 30 rabbits per hectare might help to optimise the efficiency inside enclosures.

The Groningen hypothermic liver perfusion pump : Functional evaluation of a new machine perfusion system

NARCIS (Netherlands)

van der Plaats, A.; Maathuis, M. H. J.; Hart, N. A. 't; Bellekom, A. A.; Hofker, H. S.; van der Houwen, E. B.; Verkerke, G. J.; Leuvenink, H. G. D.; Verdonck, P.; Ploeg, R. J.; Rakhorst, G.

2006-01-01

To improve preservation of donor livers, we have developed a portable hypothermic machine perfusion (HMP) system as an alternative for static cold storage. A prototype of the system was built and evaluated on functionality. Evaluation criteria included 24 h of adequate pressure controlled perfusion,

Maxillary palatal ramp prosthesis: A prosthodontic solution to manage mandibular deviation following surgery

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Sampa Ray (Bhattacharya

2015-01-01

Full Text Available Mandibular resection following surgical treatment for neoplastic lesions of the oral cavity leads to numerous complications including altered mandibular movements, disfigurement, difficult in swallowing, impaired speech and articulation, and deviation of the mandible towards the resected site. Various prosthetic methods are employed to reduce or minimize mandibular deviation and improve and restore the lost functions and esthetic, like maxillomandibular fixation, implant supported prosthesis, removable mandibular guide flange prosthesis, and palatal based guidance restoration. This clinical report describes the rehabilitation of a patient following segmental mandibulectomy using palatal ramp prosthesis.

[Trigeminal motor paralysis and dislocation of the temporo-mandibular joints].

Science.gov (United States)

Ohkawa, S; Yoshida, T; Ohsumi, Y; Tabuchi, M

1996-07-01

A 64-year-old woman with diabetes mellitus was admitted to our hospital with left hemiparesis of sudden onset. A brain MRI demonstrated a cerebral infarction in the ventral part of the right lower pons. When left hemiparesis worsened, she had dislocation of the temporo-mandibular joints repeatedly. Then, her lower jaw deviated to the right when she opened her mouth. Also, there was decreased contraction of the right masseter when she clenched her teeth. These findings suggest that there was trigeminal motor paralysis on the right side resulting from involvement of the intrapontine trigeminal motor nerve. She has no history of dislocation of the temporo-mandibular joints. An X-ray film showed that the temporo-mandibular joints were intact. Thus, it is possible that deviation of the lower jaw was the cause of this dislocation. We suspect that dislocation of the temporo-mandibular joints may occur as a complication of unilateral trigeminal motor paralysis. This has not been reported to our knowledge.

Radiofrequency ablation combined with transcatheter arterial embolisation in rabbit liver: investigation of the ablation zone according to the time interval between the two therapies.

Science.gov (United States)

Lee, I J; Kim, Y I; Kim, K W; Kim, D H; Ryoo, I; Lee, M W; Chung, J W

2012-11-01

This study was designed to evaluate the extent of the radiofrequency ablation zone in relation to the time interval between transcatheter arterial embolisation (TAE) and radiofrequency ablation (RFA) and, ultimately, to determine the optimal strategy of combining these two therapies for hepatocellular carcinoma. 15 rabbits were evenly divided into three groups: Group A was treated with RFA alone; Group B was treated with TAE immediately followed by RFA; and Group C was treated with TAE followed by RFA 5 days later. All animals underwent perfusion CT (PCT) scans immediately after RFA. Serum liver transaminases were measured to evaluate acute liver damage. Animals were euthanised for pathological analysis of ablated tissues 10 days after RFA. Non-parametric analyses were conducted to compare PCT indices, the RFA zone and liver transaminase levels among the three experimental groups. Group B showed a significantly larger ablation zone than the other two groups. Arterial liver perfusion and hepatic perfusion index represented well the perfusion decrease after TAE on PCT. Although Group B showed the most elevated liver transaminase levels at 1 day post RFA, the enzymes decreased to levels that were not different from the other groups at 10 days post-RFA. When combined TAE and RFA therapy is considered, TAE should be followed by RFA as quickly as possible, as it can be performed safely without serious hepatic deterioration, despite the short interval between the two procedures.

[Bruxism, temporo-mandibular dysfunction and botulinum toxin].

Science.gov (United States)

Chikhani, L; Dichamp, J

2003-07-01

Tooth grinding and tooth clenching are unvoluntary mainly nocturnal habits that result in an hypertrophy of masseter and temporalis muscles with an unbalance between opening and closing muscles of the jaw and lead to an alteration of mandibular condyles movements and to hyper pressure in the temporo-mandibular joints (TMJ) which can generate severe pain. Intra muscular injections of botulinum toxin permit to restablish the balance between closing and opening muscles, to relieve pain, to treat masseteric hypertrophy with improvement of face outline and to recover a normal cinetic of temporo-mandibular joints. Moreover, botulinum toxin injections permit to quit habits of tooth grinding and clenching and one single session of injections is curative for 2/3 of the patients. There are no side effects apart from slight diffusion to superficial muscles of the face resulting in a "fixed" smile for about 6 to 8 weeks. So injections of botulinum toxin in masseter and temporalis muscles are an efficient treatment of bruxism and TMJ dysfunction, cheap with no lasting side effect.

Evaluation of Recurring Esthetic Dental Proportion in Natural Mandibular Anterior Dentition

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Dipti S Shah

2015-01-01

Results: After calculating proportions in mandibular anterior teeth, P value was found to be statistically insignificant (P > 0.05. Conclusion: Within the limitations of the study, RED proportion was not seen in mandibular natural dentition.

Vicarious audiovisual learning in perfusion education.

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Rath, Thomas E; Holt, David W

2010-12-01

Perfusion technology is a mechanical and visual science traditionally taught with didactic instruction combined with clinical experience. It is difficult to provide perfusion students the opportunity to experience difficult clinical situations, set up complex perfusion equipment, or observe corrective measures taken during catastrophic events because of patient safety concerns. Although high fidelity simulators offer exciting opportunities for future perfusion training, we explore the use of a less costly low fidelity form of simulation instruction, vicarious audiovisual learning. Two low fidelity modes of instruction; description with text and a vicarious, first person audiovisual production depicting the same content were compared. Students (n = 37) sampled from five North American perfusion schools were prospectively randomized to one of two online learning modules, text or video.These modules described the setup and operation of the MAQUET ROTAFLOW stand-alone centrifugal console and pump. Using a 10 question multiple-choice test, students were assessed immediately after viewing the module (test #1) and then again 2 weeks later (test #2) to determine cognition and recall of the module content. In addition, students completed a questionnaire assessing the learning preferences of today's perfusion student. Mean test scores from test #1 for video learners (n = 18) were significantly higher (88.89%) than for text learners (n = 19) (74.74%), (p audiovisual learning modules may be an efficacious, low cost means of delivering perfusion training on subjects such as equipment setup and operation. Video learning appears to improve cognition and retention of learned content and may play an important role in how we teach perfusion in the future, as simulation technology becomes more prevalent.

Cementoblastoma Relating to Right Mandibular Second Primary Molar

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Sivakumar Nuvvula

2016-01-01

Full Text Available Cementoblastoma is a benign lesion of the odontogenic ectomesenchymal origin. It rarely occurs in primary dentition. This report describes a case of a cementoblastoma relating to the right mandibular second primary molar in a 7-year-old girl. Her panoramic radiograph revealed a well-defined radiopaque lesion with a radiolucent border extending from the distal surface of the mandibular right first primary molar to the distal surface of mandibular second primary molar. The tumor was attached to the mesial root of primary second molar and was excised along with the teeth involved and sent for histopathological evaluation, which showed irregular trabeculae of mineralized tissue interspersed with fibrovascular connective tissue, trabeculae of mineralized tissue with prominent reversal lines, and peripheral rimming of the mineralized tissue with blast cells. On a six-month follow-up, there has been no recurrence of the lesion.

Association between condylar morphology and inflammation in experimental temporomandibular joint TMJ arthritis

DEFF Research Database (Denmark)

Kristensen, Kasper Dahl; Stoustrup, Peter bangsgaard; Küseler, Annelise

not previously been investigated. Aim: We studied the effects of antigen-induced arthritis on the bony structures in rabbit mandibular condylar development, in particular the morphological changes and the bone micro-architecture. Materials and Methods: Included were juvenile rabbits with ovalbumin-induced TMJ...... arthritis treated with intraarticular saline, intra-articular etanercept (an anti-TNF-α drug) or subcutaneous etanercept. One TMJ from each animal was scanned using micro-computed tomography and structural parameters were calculated. Three-dimensional reconstructions of the mandibular condyle were scored...... blindly by two independent observers as normal or abnormal. TMJs were stratified for condylar morphology and evaluated against data on inflammation, trabecular structural parameters, and overall mandibular growth. Mineral apposition rate was measured using fluorochrome labelling. Results and discussion...

[Inferior hemiarthroplasty of the temporo-mandibular joint with articulated condylar prosthesis type Stryker].

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Bucur, A; Dincă, O; Totan, C; Ghită, V

2007-01-01

The optimal reconstruction of the mandible and of the temporo-mandibular joint after mandibular hemi-resection with disarticulation is still controversial in literature. This paperwork presents our experience on four cases in the reconstruction of the mandible together with the inferior arthroplasty of the temporo-mandibular joint, after the resection of extended benign tumors of the mandible, based on fibular free vascularized grafts having attached a Stryker titanium condylar prosthesis reconstructing the inferior segment of the temporo-mandibular joint. Our results for the this technique were excellent, with a functional rehabilitation very close to normal. After reviewing the various techniques and their arguments in literature, with accent on the TMJ reconstruction, we consider this method to be optimal for the reconstruction of mandibular defects in patients with neoplastic conditions.

Pulmonary ventilation and perfusion abnormalities and ventilation perfusion imbalance in children with pulmonary atresia or extreme tetralogy of Fallot

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Dowdle, S.C.; Human, D.G.; Mann, M.D. (Univ. of Cape Town (South Africa))

1990-08-01

Xenon-133 lung ventilation and perfusion scans were done preoperatively after cardiac catheterization and cineangiocardiography in 19 children; 6 had pulmonary atresia with an intact ventricular septum and hypoplastic right ventricle, 4 pulmonary atresia with associated complex univentricular heart, and 9 extreme Tetralogy of Fallot. The four patients with discrepancies in the sizes of the left and right pulmonary arteries on angiography had marked asymmetry of pulmonary perfusion and ventilation-perfusion imbalance on scintigraphy. Similar degrees of asymmetry and imbalance were present in 6 of the 15 children with equal-size pulmonary vessels. Asymmetry of pulmonary perfusion and ventilation-perfusion imbalance were associated with a poor prognosis.

Pulmonary ventilation and perfusion abnormalities and ventilation perfusion imbalance in children with pulmonary atresia or extreme tetralogy of Fallot

International Nuclear Information System (INIS)

Dowdle, S.C.; Human, D.G.; Mann, M.D.

1990-01-01

Xenon-133 lung ventilation and perfusion scans were done preoperatively after cardiac catheterization and cineangiocardiography in 19 children; 6 had pulmonary atresia with an intact ventricular septum and hypoplastic right ventricle, 4 pulmonary atresia with associated complex univentricular heart, and 9 extreme Tetralogy of Fallot. The four patients with discrepancies in the sizes of the left and right pulmonary arteries on angiography had marked asymmetry of pulmonary perfusion and ventilation-perfusion imbalance on scintigraphy. Similar degrees of asymmetry and imbalance were present in 6 of the 15 children with equal-size pulmonary vessels. Asymmetry of pulmonary perfusion and ventilation-perfusion imbalance were associated with a poor prognosis

Study of pulp chamber morphology of primary mandibular molars using spiral computed tomography.

Science.gov (United States)

Selvakumar, Haridoss; Kavitha, Swaminathan; Vijayakumar, Rajendran; Eapen, Thomas; Bharathan, Rajendran

2014-11-01

The purpose of this study was to evaluate the pulp chamber morphology in primary mandibular molars using spiral computed tomography (SCT). Sixty extracted primary mandibular molars were scanned using SCT for the (i) distance between the central fissure to furcation, (ii) distance between the central fissure to the floor of the pulp chamber, (iii) height of the pulp chamber (roof-floor), (iv) distance between the floor of the pulp chamber to the furcation. The mean and standard deviation was analyzed using statistical package for the social sciences (SPSS) program. The results of this study show that the average mean distance from the central fissure to the floor of the pulp chamber is 5.07 mm in first mandibular primary molar and 5.54 mm in second mandibular primary molar. It can be concluded that the greatest depth to which a bur can go during access opening without perforating the furcation in first primary mandibular molar is 5.07 mm and 5.54 mm in second primary mandibular molar.

Influence of mastication and edentulism on mandibular bone density.

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Chou, Hsuan-Yu; Satpute, Devesh; Müftü, Ali; Mukundan, Srinivasan; Müftü, Sinan

2015-01-01

The aim of this study was to demonstrate that external loading due to daily activities, including mastication, speech and involuntary open-close cycles of the jaw contributes to the internal architecture of the mandible. A bone remodelling algorithm that regulates the bone density as a function of stress and loading cycles is incorporated into finite element analysis. A three-dimensional computational model is constructed on the basis of computerised tomography (CT) images of a human mandible. Masticatory muscle activation involved during clenching is modelled by static analysis using linear optimisation. Other loading conditions are approximated by imposing mandibular flexure. The simulations predict that mandibular bone density distribution results in a tubular structure similar to what is observed in the CT images. Such bone architecture is known to provide the bone optimum strength to resist bending and torsion during mastication while reducing the bone mass. The remodelling algorithm is used to simulate the influence of edentulism on mandibular bone loss. It is shown that depending on the location and number of missing teeth, up to one-third of the mandibular bone mass can be lost due to lack of adequate mechanical stimulation.

Preliminary optical coherence tomography investigation of the temporo-mandibular joint disc

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Mărcăuteanu, Corina; Demjan, Enikö; Sinescu, Cosmin; Negrutiu, Meda; Motoc, Adrian; Lighezan, Rodica; Vasile, Liliana; Hughes, Mike; Bradu, Adrian; Dobre, George; Podoleanu, Adrian G.

2010-02-01

Aim and objectives. The morphology and position of the temporo-mandibular disc are key issues in the diagnosis and treatment of arthrogenous temporo-mandibular disorders. Magnetic resonance imaging and arthroscopy are used today to identify: flattening of the pars posterior of the disc, perforation and/or adhesions in the pars intermedia of the disc and disc displacements. The present study proposes the investigation of the temporo-mandibular joint disc by optical coherence tomography (OCT). Material and methods. 8 human temporo-mandibular joint discs were harvested from dead subjects, under 40 year of age, and conserved in formalin. They had a normal morphology, with a thicker pars posterior (2,6 mm on the average) and a thinner pars intermedia (1mm on the average). We investigated the disc samples using two different OCT systems: an en-face OCT (time domain (TD)-OCT) system, working at 1300 nm (C-scan and B-scan mode) and a spectral OCT system (a Fourier domain (FD)-OCT) system , working at 840 nm (B-scan mode). Results. The OCT investigation of the temporo-mandibular joint discs revealed a homogeneous microstructure. The longer wavelength of the TD-OCT offers a higher penetration depth (2,5 mm in air), which is important for the analysis of the pars posterior, while the FD-OCT is much faster. Conclusions: OCT is a promising imaging method for the microstructural characterization of the temporo-mandibular disc.

Glenoid fossa position in Class II malocclusion associated with mandibular retrusion.

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Giuntini, Veronica; De Toffol, Laura; Franchi, Lorenzo; Baccetti, Tiziano

2008-09-01

To assess the position of the glenoid fossa in subjects with Class II malocclusion associated with mandibular retrusion and normal mandibular size in the mixed dentition. A sample of 30 subjects (16 male, 14 female), age 9 years +/- 6 months, with skeletal and dental Class II malocclusion associated with mandibular retrusion, normal skeletal vertical relationships, and normal mandibular dimensions, was compared with a matched group of 37 subjects (18 male, 19 female) with skeletal and dental Class I relationships. The comparisons between the Class II group and the control group on the cephalometric measures for the assessment of glenoid fossa position were performed by means of a nonparametric test for independent samples (Mann-Whitney U-test, P < .05). Subjects with Class II malocclusion presented with a significantly more distal position of the glenoid fossa, when compared with the control group as measured by means of three parameters (GF-S on FH, GF-Ptm on FH, and GF-FMN). A posteriorly displaced glenoid fossa is a possible diagnostic feature of Class II malocclusion associated with mandibular retrusion. An effective cephalometric measurement to evaluate glenoid fossa position is the distance from the glenoid fossa to the frontomaxillonasal suture (GF-FMN).

Mandibular Two Mini Implants Overdenture Using Magnetic Attachments: A Case Report

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Anna Miyayasu

2017-12-01

Full Text Available Many patients with an edentulous mandible struggle to use complete dentures. The instability of such dentures caused by the lack of retention, often causes discomfort, as well as functional and psychosocial problems, which can be signifcantly improved using implant overdentures with retentive attachments. This case report describes a successful case of a mandibular implant overdenture using two mini implants and magnetic attachments for an elderly edentulous patient. Case Report: A 62-year-old female with a thin mandibular bone ridge presented with complaints of pain caused by an unstable and unretentive complete mandibular denture. This patient received two mini implants (diameter: 2.6 mm; length: 12 mm with magnetic attachments. After three months, magnetic assemblies with magnetic attraction of 400 gf were incorporated into the intaglio surface of her mandibular overdenture. At 11 months, magnetic attraction was changed from 400 gf to 600 gf to provide a stronger magnetic force for improving the retention of this denture. Conclusion: Based on a two-year follow-up period, the mandibular two mini implants overdenture with magnetic attachments was successful in improving the patient’s general satisfaction with her dentures

Signaling pathways regulating the expression of Prx1 and Prx2 in the Chick Mandibular Mesenchyme

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Doufexi, Aikaterini-El; Mina, Mina

2009-01-01

Prx1 and Prx2 are members of the aristaless-related homeobox genes shown to play redundant but essential roles in morphogenesis of the mandibular processes. To gain insight into the signaling pathways that regulate expression of Prx genes in the mandibular mesenchyme, we used the chick as a model system. We examined the patterns of gene expression in the face and the roles of signals derived from the epithelium on the expression of Prx genes in the mandibular mesenchyme. Our results demonstrated stage-dependent roles of mandibular epithelium on the expression of Prx in the mandibular mesenchyme and provide evidence for positive roles of members of the fibroblast and hedgehog families derived from mandibular epithelium on the expression of Prx genes in the mandibular mesenchyme. Our studies suggest that endothelin-1 signaling derived from the mesenchyme is involved in restricting the expression of Prx2 to the medial mandibular mesenchyme. PMID:18942149

Clinical application of cerebral dynamic perfusion studies

International Nuclear Information System (INIS)

DeLand, F.H.

1975-01-01

Radionuclide cerebral perfusion studies are assuming a far greater importance in the detection and differential diagnosis of cerebral lesions. Perfusion studies not only contribute to the differential diagnosis of lesions but in certain cases are the preferred methods by which more accurate clinical interpretations can be made. The characteristic blood flow of arterio-venous malformations readily differentiates this lesion from neoplasms. The decreased perfusion or absent perfusion observed in cerebral infarctions is diagnostic without concurrent evidence from static images. Changes in rates and direction of blood flow contribute fundamental information to the status of stenosis and vascular occlusion and, in addition, offer valuable information on the competency and routes of collateral circulation. The degree of cerebral perfusion after cerebral vascular accidents appears to be directly related to patient recovery, particularly muscular function. Cerebral perfusion adds a new parameter in the diagnosis of subdural haematomas and concussion and in the differentiation of obscuring radioactivity from superficial trauma. Although pictorial displays of perfusion blood flow will offer information in most cerebral vascular problems, the addition of computer analysis better defines temporal relationships of regional blood flow, quantitative changes in flow and the detection of the more subtle increases or decreases in cerebral blood flow. The status of radionuclide cerebral perfusion studies has taken on an importance making it the primary modality for the diagnosis of cerebral lesions. (author)

Management of periodontally compromised mandibular molar with Hemisectioning: A case report

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Bandu Napte

2014-01-01

Full Text Available Introduction: Hemisection involves sectioning of a periodontally involved mandibular molar so as to remove the involved root and save the remaining tooth. This procedure helps in saving a tooth which otherwise would have been deemed for extraction. Hemisection refers to removal or separation of root with its accompanying crown portion of two-rooted teeth, most commonly mandibular molars. Method: In this case report, an advanced Endo-Perio lesion on a left mandibular first molar was successfully treated by root-canal treatment and hemisection. This procedure helps preserve the tooth structure, alveolar bone and promote cost savings over other treatment options. Conclusion: Hemisection is a treatment option for saving a mandibular molar which is in advanced stage of periodontal disease of one root. Removal of the affected root will help in retaining the remaining tooth structure.

Evaluation of mandibular condyles in children with unilateral posterior crossbite.

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Illipronti-Filho, Edson; Fantini, Solange Mongelli de; Chilvarquer, Israel

2015-01-01

The relationship of mandibular condyle dimensions and its association with unilateral posterior crossbite (UPXB) has been suggested in the literature. The purpose of this prospective study was to evaluate mandibular condyles on the left and right sides and between crossed and non-crossed sides in the sagittal and coronal planes, using cone-beam computed tomography (CBCT). Twenty CBCT images of 40 temporo mandibular joints (TMJs) in individuals in mixed dentition phase, which included 9 males (mean 7.9 years) and 11 females (mean 8.2 years), with unilateral posterior crossbite without premature contacts and functional mandibular shifts and with transverse maxillary deficiency. The criteria for sample exclusion included the presence of painful symptoms, facial trauma history, systemic diseases such as juvenile rheumatoid arthritis, mouth opening limitation (anomalies, and skeletal asymmetries that may result in TMJ disorders. Dimensional measurements of the condyles between the right and left sides and crossed and non-crossed sides in sagittal and coronal view were made. There was no significant difference between the measurements of the crossed and non-crossed sides in both sagittal and coronal view. These findings suggest that the presence of unilateral posterior crossbite in children with UPXB did not result in changes between the mandibular condyles in the right and left sides or between the crossed and non-crossed sides in the coronal or sagittal plane.

Mandibular Symmetrical Bilateral Canine-Lateral Incisors Transposition: Its Early Diagnosis and Treatment Considerations.

Science.gov (United States)

Shapira, Yehoshua; Finkelstein, Tamar; Kadry, Rana; Schonberger, Shirley; Shpack, Nir

2016-01-01

Bilateral mandibular tooth transposition is a relatively rare dental anomaly caused by distal migration of the mandibular lateral incisors and can be detected in the early mixed dentition by radiographic examination. Early diagnosis and interceptive intervention may reduce the risk of possible transposition between the mandibular canine and lateral incisor. This report illustrates the orthodontic management of bilateral mandibular canine-lateral incisor transposition. Correct positioning of the affected teeth was achieved on the left side while teeth on the right side were aligned in their transposed position. It demonstrates the outcome of good alignment of the teeth in the dental arch.

Dynamic perfusion CT: Optimizing the temporal resolution for the calculation of perfusion CT parameters in stroke patients

Energy Technology Data Exchange (ETDEWEB)

Kaemena, Andreas [Department of Radiology, Charite-Medical University Berlin, Augustenburger Platz 1, D-13353 Berlin (Germany)], E-mail: andreas.kaemena@charite.de; Streitparth, Florian; Grieser, Christian; Lehmkuhl, Lukas [Department of Radiology, Charite-Medical University Berlin, Augustenburger Platz 1, D-13353 Berlin (Germany); Jamil, Basil [Department of Radiotherapy, Charite-Medical University Berlin, Schumannstr. 20/21, D-10117 Berlin (Germany); Wojtal, Katarzyna; Ricke, Jens; Pech, Maciej [Department of Radiology, Charite-Medical University Berlin, Augustenburger Platz 1, D-13353 Berlin (Germany)

2007-10-15

Purpose: To assess the influence of different temporal sampling rates on the accuracy of the results from cerebral perfusion CTs in patients with an acute ischemic stroke. Material and methods: Thirty consecutive patients with acute stroke symptoms received a dynamic perfusion CT (LightSpeed 16, GE). Forty millilitres of iomeprol (Imeron 400) were administered at an injection rate of 4 ml/s. After a scan delay of 7 s, two adjacent 10 mm slices at 80 kV and 190 mA were acquired in a cine mode technique with a cine duration of 49 s. Parametric maps for the blood flow (BF), blood volume (BV) and mean transit time (MTT) were calculated for temporal sampling intervals of 0.5, 1, 2, 3 and 4 s using GE's Perfusion 3 software package. In addition to the quantitative ROI data analysis, a visual perfusion map analysis was performed. Results: The perfusion analysis proved to be technically feasible with all patients. The calculated perfusion values revealed significant differences with regard to the BF, BV and MTT, depending on the employed temporal resolution. The perfusion contrast between ischemic lesions and healthy brain tissue decreased continuously at the lower temporal resolutions. The visual analysis revealed that ischemic lesions were best depicted with sampling intervals of 0.5 and 1 s. Conclusion: We recommend a temporal scan resolution of two images per second for the best detection and depiction of ischemic areas.

Root canal morphology and variations of mandibular premolars by clearing technique: an in vitro study.

Science.gov (United States)

Parekh, Vaishali; Shah, Nimisha; Joshi, Hardik

2011-07-01

The aim of this study was to compare internal anatomy between first and second mandibular premolars and to study different percentage variations of root canal morphology of mandibular premolars in Gujarat population based on Vertucci's classification by clearing technique. A total of 80 extracted intact permanent mandibular premolars (40 each mandibular first premolar and mandibular second premolar) with fully formed apices were collected. Access cavity was prepared with endo access kit, all samples were placed in 2.5% sodium hypochlorite for 48 hours, after that all samples were washed in running water for 2 hours. After washing, all samples were transferred to 5% nitric acid, for decalcification, for 72 hours, with the acid being changed every 24 hours and stirred once every 8 hours. All samples were washed in running water and dehydrated using ascending grades (70%, 80%, 90% and 100%) of isopropyl alcohol for 2 days. Finally, they were rendered transparent by immersion in methyl salicylate for 15 minutes and then India ink dye was injected into the access cavity. The anatomy of the root canal was observed and classified based on the Vertucci's classification. Parametric Z-test was used to compare the variation between mandibular first and second premolars. In mandibular first premolar, type 1 was found in 20%, type 2 was 5%, type 3 was 5%, type 4 was 25%, type 5 was 12.5% and type 6 was 2.5% of total samples. Whereas, in mandibular second premolar, type 1 was found in 80% out of all samples, type 4 was 2.5%, type 5 was 17.5%. Type 2, type 3, type 6, type 7 and type 8 were not found in this study. Mandibular first premolar showed higher variation (75%) compared to mandibular second premolar (37.5%). The knowledge of variations in the root canal morphology of the mandibular premolars can enhance the level of endodontic treatment of mandibular premolars. Root canal morphology, Vertucci's classification, Clearing technique. How to cite this article: Parekh V, Shah N

Management of mandibular body fractures in pediatric patients: a case report with review of literature.

Science.gov (United States)

John, Baby; John, Reena R; Stalin, A; Elango, Indumathi

2010-10-01

Mandibular fractures are relatively less frequent in children when compared to adults, which may be due to the child's protected anatomic features and infrequent exposure of children to alcohol related traffic accidents. Treatment principles of mandibular fractures differ from that of adults due to concerns regarding mandibular growth and development of dentition. A case of a 4.5-year-old boy with fractured body of mandible managed by closed reduction using open occlusal acrylic splint and circum mandibular wiring is presented. This article also provides a review of literature regarding the management of mandibular body fracture in young children.

Management of mandibular body fractures in pediatric patients: A case report with review of literature

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Baby John

2010-01-01

Full Text Available Mandibular fractures are relatively less frequent in children when compared to adults, which may be due to the child′s protected anatomic features and infrequent exposure of children to alcohol related traffic accidents. Treatment principles of mandibular fractures differ from that of adults due to concerns regarding mandibular growth and development of dentition. A case of a 4.5-year-old boy with fractured body of mandible managed by closed reduction using open occlusal acrylic splint and circum mandibular wiring is presented. This article also provides a review of literature regarding the management of mandibular body fracture in young children.

Characteristics of Brain Perfusion in Patients of Parkinson's Disease

International Nuclear Information System (INIS)

Jeong, Young Jin; Park, Min Jung; Kim, Jae Woo; Kang, Young Kang

2008-01-01

It was well known that cerebral blood perfusion is normal or diffusely decreased in the majority of patients with Parkinson's disease (PD). Actually we interpreted brain perfusion SPECT images of PD patients in the clinical situation, we observed various cerebral perfusion patterns in patients with PD. So we performed brain perfusion SPECT to know the brain perfusion patterns of PD patients and the difference of perfusion patterns according to the sex and the age. Also we classified PD patients into small groups based on the brain perfusion pattern. Two hundred nineteen patients (M: 70, F: 149, mean age: 62.9±6.9 y/o) who were diagnosed as PD without dementia clinically and 55 patients (M: 15, F: 40, mean age: 61.4±9.2 y/o) as normal controls who had no past illness history were performed 99m Tc-HMPAO brain perfusion SPECT and neuropsychological test. At first, we compared all patients with PD and normal controls. Brain perfusion in left inferior frontal gyrus, left insula, left transverse temporal gyrus, left inferior parietal lobule, left superior parietal lobule, right precuneus, right caudate tail were lower in patients with PD than normal controls. Secondly, we compared male and female patients with PD and normal controls, respectively. Brain perfusion SPECT showed more decreased cerebral perfusion in left hemisphere than right side in both male and female patients compared to normal controls. And there was larger hypoperfusion area in female patients compared with male. Thirdly, we classified patients with PD and normal controls into 4 groups according to the age and compared brain perfusion respectively. In patient below fifties, brain perfusion in both occipitoparietal and left temporal lobe were lower in PD group. As the patients with PD grew older, hypoperfusion area were shown in both frontal, temporal and limbic lobes. Fourthly, We were able to divide patients into small groups based on cerebral perfusion pattern. There was normal cerebral blood

Direct assessment of lipoprotein outflow from in vivo-labeled arterial tissue as determined in an in vitro perfusion system.

Science.gov (United States)

Björnheden, T; Bondjers, G; Wiklund, O

1998-12-01

The rate of cholesterol deposition during the atherosclerotic process is determined by the balance between the inflow and outflow of plasma lipoproteins in the arterial wall. Whereas the rate of inflow may be measured directly, the rate of outflow has most often been calculated indirectly from lipoprotein uptake by using the 2-compartment model. One objection against such calculations is that lipoprotein binding is not being considered. In the present study 2 different protocols were used to obtain a direct measure of the outflow of lipoproteins from atherosclerotic rabbit aortas. Thus, 3 rabbits with experimental atherosclerosis were given 125I-LDL intravenously and 3 were given [14C]cholesterol perorally. Twenty-four hours later the aortas were removed and the outflow of label was monitored during in vitro perfusion. Despite the different protocols, our results were consistent and indicated that fractional loss relative to whole tissue was approximately 0.01 pool/h, which is 1 order of magnitude lower than current estimates based on the 2-compartment model (0.04 to 0.4 pool/h). Furthermore, whereas as much as 2/3 to 3/4 of the tracer that had entered the arterial wall was effectively trapped, the remainder equilibrated at a faster rate (0.06 pool/h). In conclusion, it seems that tissue binding constitutes a prominent and possibly underrated mechanism of lipoprotein deposition, at least in the atherosclerotic rabbit aorta. Furthermore, this means that current estimates of lipoprotein exchange parameters based on the 2-compartment model (eg, fractional loss) may rest on invalid assumptions and should be regarded with caution.

Preparation and evaluation of (131I)AgI particles: potential lungs perfusion imaging agent

International Nuclear Information System (INIS)

Chattopadhyay, Sankha; Das, Sujata Saha; Sinha, Samarendu; Sarkar, Bharat Ranjan; Ganguly, Shantanu; Chandra, Susmita; De, Kakali; Mishra, Mridula

2010-01-01

Since the discovery of iodine-131 (t 1/2 : 8 d) by Livingood and Seaborg (1938), this, and other radioisotopes of iodine, have found widespread use in nuclear medicine. The purpose of the present work was to formulate Ag 131 I particles and bio-evaluate the same. The Ag 131 I particles were prepared in acidic condition having 100% R.C. Purity. The biological evaluation of Ag 131 1 particles was made by injecting about 111-185 MBq of Ag 131 I particles preparations in female albino rabbits (2-2.5 kg weight) intravenously by femoral vein under urethane anesthesia. Imaging studies were performed under Gamma Camera. The entire amount of the Ag 131 I particles were found to deposit in the lungs and remained there almost unchanged for a certain period of time after the intervenous administration. The images showed excellent, uniform lung uptake with no interference from liver and spleen to the lower regions of right and left lobes. It showed a high accumulation in the rabbits lungs (>99%) and remained constant for at least for 20 min. It is also worthy to study with 123 I/ 124 I labelled AgI for lung imaging study. In conclusion, the synthetic radiopharmaceutical ( 131 I)-Silver iodide colloid can be prepared with a large particle size, in a simple and practical manner, and it has good potential for use as a perfusion imaging agent in lung scans

Regional Cerebral Perfusion in Progressive Supranuclear Palsy

Energy Technology Data Exchange (ETDEWEB)

Lee, Won Yong; Lee, Ki Hyeong; Yoon, Byung Woo; Lee, Sang Bok; Jeon, Beom S. [Samsung Medical Center, Seoul (Korea, Republic of); Lee, Kyung Han; Lee, Myung Chul [Seoul National University College of Medicine, Seoul (Korea, Republic of)

1996-03-15

Progressive supranuclear palsy (PSP) is a Parkinson-plus syndrome characterized clinically by supranuclear ophthalmoplegia, pseudobulbar palsy, axial rigidity, bradykinesia, postural instability and dementia. Presence of dementia and lack of cortical histopathology suggest the derangement of cortical function by pathological changes in subcortical structures in PSP, which is supported by the pattern of behavioral changes and measurement of brain metabolism using positron emission tomography. This study was done to examine whether there are specific changes of regional cerebral perfusion in PSP and whether there is a correlation between severity of motor abnormaility and degree of changes in cerebral perfusion. We measured regional cerebral perfusion indices in 5 cortical and 2 subcortical areas in 6 patients with a clinical diagnosis of PSP and 6 healthy age and sex matched controls using Tc-99m-HMPAO SPECT. Compared with age and sex matched controls, only superior frontal regional perfusion index was significantly decreased in PSP (p<0.05). There was no correlation between the severity of the motor abnormality and any of the regional cerebral perfusion indices (p>0.05). We affirm the previous reports that perfusion in superior frontal cortex is decreased in PSP. Based on our results that there was no correlation between severity of motor abnormality and cerebral perfusion in the superior frontal cortex, nonmotoric symptoms including dementia needs to be looked at whether there is a correlation with the perfusion abnormality in superior frontal cortex

Conservative Management of Unilateral Fractures of the Mandibular Rami in Horses.

Science.gov (United States)

Jansson, Nicolai

2016-11-01

To report the outcome of conservative management of unilateral fractures of the mandibular rami in horses. Retrospective case series. 24 client-owned horses with unilateral mandibular fractures METHODS: Medical records (January 2000-January 2014) of horses with unilateral mandibular ramus fractures were retrieved. Only conservatively managed horses with follow-up information were included. Follow-up information on clinical outcome was retrieved from the medical records (n=11) or obtained by telephone interviews with the owners or trainers (n=13). Twenty-three horses (96%) returned to their previous or intended use and had no clinically evident masticatory or fracture healing-related problems at the time of follow-up. The owner of 1 horse (4%) reported it had tooth loosening, feed impaction, and masticatory problems. Conservative management of unilateral fractures of the mandibular rami is a treatment option in horses. © Copyright 2016 by The American College of Veterinary Surgeons.

Concomitant administration of nitrous oxide and remifentanil reduces oral tissue blood flow without decreasing blood pressure during sevoflurane anesthesia in rabbits.

Science.gov (United States)

Kasahara, Masataka; Ichinohe, Tatsuya; Okamoto, Sota; Okada, Reina; Kanbe, Hiroaki; Matsuura, Nobuyuki

2015-06-01

To determine whether continuous administration of nitrous oxide and remifentanil—either alone or together—alters blood flow in oral tissues during sevoflurane anesthesia. Eight male tracheotomized Japanese white rabbits were anesthetized with sevoflurane under mechanical ventilation. Heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), common carotid arterial blood flow (CCBF), tongue mucosal blood flow (TMBF), mandibular bone marrow blood flow (BBF), masseter muscle blood flow (MBF), upper alveolar tissue blood flow (UBF), and lower alveolar tissue blood flow (LBF) were recorded in the absence of all test agents and after administration of the test agents (50 % nitrous oxide, 0.4 μg/kg/min remifentanil, and their combination) for 20 min. Nitrous oxide increased SBP, DBP, MAP, CCBF, BBF, MBF, UBF, and LBF relative to baseline values but did not affect HR or TMBF. Remifentanil decreased all hemodynamic variables except DBP. Combined administration of nitrous oxide and remifentanil recovered SBP, DBP, MAP, and CCBF to baseline levels, but HR and oral tissue blood flow remained lower than control values. Our findings suggest that concomitant administration of nitrous oxide and remifentanil reduces blood flow in oral tissues without decreasing blood pressure during sevoflurane anesthesia in rabbits.

Some factors affecting rabbit production under egyptian environment

International Nuclear Information System (INIS)

Nessim, M.Z.

1994-01-01

The present work was carried out in the rabbit of the department of animal production, faculty of agriculture, Zagazig University, Zagazig, Egypt, Blood biochemical analysis and hormonal assay were conducted in tracer bio climatology Unit., Department of radiobiology, nuclear research centre, Atomic Energy Authority, Cairo, Egypt. Eighty male New Zealand white (NZW) and 80 male californian (Cal) rabbits aged 5-6 weeks were used. The animals were housed in rabbit building, naturally ventilated. Rabbits cages were provided with automatic nipple drinkers and drinking and drinking water ad libitum.Rabbits were fed ad libitum on balanced growing pelted rabbit ration. 21 tabs.,13 figs.,158 refs

Light colour preference of growing rabbits

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Zsolt Szendrő

2010-01-01

Full Text Available The objective of the experiment was to evaluate the light colour preference of growing rabbits placed in a free-choice cage. The experiment was carried out on 128 Pannon White growing rabbits weaned at the age of 5 weeks and placed into blocks (2m2 of four cages. The rabbits could move freely among the four cages (0.5m2 each through swing doors. The cages differed only in the colour of the light applied (white, yellow, green or blue. The lighting schedule was 16L: 8D. From 6 until 10 weeks of age, infrared video recording was performed once a week (24 hours. The number of rabbits in each cage was counted every 15 minutes. Feed consumption was measured weekly. Between 6 and 10 weeks of age the rabbits significantly preferred white light (28.0%. The preference order was the following: yellow (26.3%, blue (23.4% and green (22.3% (P<0.001. No significant differences were recorded in the feed consumption among the cages. In conclusion, the cage preference of the rabbits was slightly affected by the light colour.

Mandibular Symmetrical Bilateral Canine-Lateral Incisors Transposition: Its Early Diagnosis and Treatment Considerations

Directory of Open Access Journals (Sweden)

Yehoshua Shapira

2016-01-01

Full Text Available Bilateral mandibular tooth transposition is a relatively rare dental anomaly caused by distal migration of the mandibular lateral incisors and can be detected in the early mixed dentition by radiographic examination. Early diagnosis and interceptive intervention may reduce the risk of possible transposition between the mandibular canine and lateral incisor. This report illustrates the orthodontic management of bilateral mandibular canine-lateral incisor transposition. Correct positioning of the affected teeth was achieved on the left side while teeth on the right side were aligned in their transposed position. It demonstrates the outcome of good alignment of the teeth in the dental arch.

Regional Cerebral Perfusion in Progressive Supranuclear Palsy

International Nuclear Information System (INIS)

Lee, Won Yong; Lee, Ki Hyeong; Yoon, Byung Woo; Lee, Sang Bok; Jeon, Beom S.; Lee, Kyung Han; Lee, Myung Chul

1996-01-01

Progressive supranuclear palsy (PSP) is a Parkinson-plus syndrome characterized clinically by supranuclear ophthalmoplegia, pseudobulbar palsy, axial rigidity, bradykinesia, postural instability and dementia. Presence of dementia and lack of cortical histopathology suggest the derangement of cortical function by pathological changes in subcortical structures in PSP, which is supported by the pattern of behavioral changes and measurement of brain metabolism using positron emission tomography. This study was done to examine whether there are specific changes of regional cerebral perfusion in PSP and whether there is a correlation between severity of motor abnormaility and degree of changes in cerebral perfusion. We measured regional cerebral perfusion indices in 5 cortical and 2 subcortical areas in 6 patients with a clinical diagnosis of PSP and 6 healthy age and sex matched controls using Tc-99m-HMPAO SPECT. Compared with age and sex matched controls, only superior frontal regional perfusion index was significantly decreased in PSP (p 0.05). We affirm the previous reports that perfusion in superior frontal cortex is decreased in PSP. Based on our results that there was no correlation between severity of motor abnormality and cerebral perfusion in the superior frontal cortex, nonmotoric symptoms including dementia needs to be looked at whether there is a correlation with the perfusion abnormality in superior frontal cortex

Computerized analysis of brain perfusion parameter images

International Nuclear Information System (INIS)

Turowski, B.; Haenggi, D.; Wittsack, H.J.; Beck, A.; Aurich, V.

2007-01-01

Purpose: The development of a computerized method which allows a direct quantitative comparison of perfusion parameters. The display should allow a clear direct comparison of brain perfusion parameters in different vascular territories and over the course of time. The analysis is intended to be the basis for further evaluation of cerebral vasospasm after subarachnoid hemorrhage (SAH). The method should permit early diagnosis of cerebral vasospasm. Materials and Methods: The Angiotux 2D-ECCET software was developed with a close cooperation between computer scientists and clinicians. Starting from parameter images of brain perfusion, the cortex was marked, segmented and assigned to definite vascular territories. The underlying values were averages for each segment and were displayed in a graph. If a follow-up was available, the mean values of the perfusion parameters were displayed in relation to time. The method was developed under consideration of CT perfusion values but is applicable for other methods of perfusion imaging. Results: Computerized analysis of brain perfusion parameter images allows an immediate comparison of these parameters and follow-up of mean values in a clear and concise manner. Values are related to definite vascular territories. The tabular output facilitates further statistic evaluations. The computerized analysis is precisely reproducible, i. e., repetitions result in exactly the same output. (orig.)

Assessment of tissue viability after frostbite injury by technetium-99m-sestamibi scintigraphy in an experimental rabbit model

Energy Technology Data Exchange (ETDEWEB)

Sarikaya, I. [Dept. of Nuclear Medicine, Kocaeli University Medical Faculty, Kocaeli (Turkey); Cemal Aygit, A. [Department of Plastic and Reconstructive Surgery, Trakya University Medical Faculty, Edirne (Turkey); Candan, L. [Department of Pathology, Trakya University Medical Faculty, Edirne (Turkey); Sarikaya, A.; Berkarda, S. [Dept. of Nuclear Medicine, Trakya University Medical Faculty, Edirne (Turkey); Tuerkyilmaz, M. [Dept. of Chemistry, Trakya University Faculty of Science, Edirne (Turkey)

2000-01-01

Frostbite causes injury to the tissue by direct ice-crystal formation at the cellular level with cellular dehydration and microvascular occlusion. Muscle that initially appears viable on reperfusion may subsequently become necrotic because of microcirculatory collapse. Since muscle is a sensitive tissue in frostbite injury, we used technetium-99m-sestamibi limb scintigraphy to assess tissue viability in an experimental rabbit model. Twelve rabbits were used for this investigation. The right hind limb of the rabbits was immersed to the ankle joint in a container filled with 90% ethanol at -25 C for 10 min. Frostbitten limbs were allowed to thaw in air at room temperature. Imaging and pathological examination of the affected limbs were performed 2 h, 24 h, 48 h and 72 h after freezing. In 2-h images, initial hypoperfusion was seen that corresponded to circulatory collapse. In 24-h images, there was hyperperfusion (so-called period of temporary reperfusion), corresponding to circulatory restoration. In 48-h images, a second hypoperfusion corresponded to viable but ischaemic tissue. In 72-h images, there was non-perfusion of the limb that correlated with the pathologically determined diagnosis of necrosis. All scintigraphic patterns correlated with pathological findings. We suggest that these scintigraphic patterns in soft tissue may be helpful in distinguishing between frank infarction and reversible ischemia and therefore may be useful in selecting early therapeutic or surgical interventions to salvage bone and soft tissue. Further studies are needed to show the usefulness of {sup 99m}Tc sestamibi scintigraphy in clinical frostbite cases. (orig.)

Prolonged vertigo and ataxia after mandibular nerve block for treatment of trigeminal neuralgia

OpenAIRE

Arvind Chaturvedi; H H Dash

2011-01-01

Common complications of neurolytic mandibular nerve block are hypoesthesia, dysesthesia, and chemical neuritis. We report a rare complication, prolonged severe vertigo and ataxia, after neurolytic mandibular blockade in a patient suffering from trigeminal neuralgia. Coronoid approach was used for right sided mandibular block. After successful test injection with local anesthetic, absolute alcohol was given for neurolytic block. Immediately after alcohol injection, patient developed nausea and...

Recurrent simple bone cyst of the mandibular condyle: a case report

Energy Technology Data Exchange (ETDEWEB)

Kim, Kyung A; Koh, Kwang Joon [Dept. of Oral and Maxillofacial Radiology, School of Dentistry, and Institute of Oral Bio Science, Chonbuk National University, Jeonju (Korea, Republic of)

2013-03-15

Cysts of the mandibular condyle are rare and can be difficult to diagnose and treat. Clinically, a simple bone cyst is asymptomatic and often discovered incidentally on routine radiographic examination. This report shows an atypical simple bone cyst occurring in the mandibular condyle showing recurrence after surgical curettage. Radiologically, this lesion involving the mandibular condyle should be distinguished from other similar lesions such as a chondriome, a central giant cell granuloma, and an aneurysmal bone cyst. Radiographic assessment was useful for forecasting the prognosis of a simple bone cyst. Possible reasons for the recurrence were discussed radiographically.

Evaluation of mandibular condyles in children with unilateral posterior crossbite

Directory of Open Access Journals (Sweden)

Edson ILLIPRONTI-FILHO

2015-01-01

Full Text Available The relationship of mandibular condyle dimensions and its association with unilateral posterior crossbite (UPXB has been suggested in the literature. The purpose of this prospective study was to evaluate mandibular condyles on the left and right sides and between crossed and non-crossed sides in the sagittal and coronal planes, using cone-beam computed tomography (CBCT. Twenty CBCT images of 40 temporo mandibular joints (TMJs in individuals in mixed dentition phase, which included 9 males (mean 7.9 years and 11 females (mean 8.2 years, with unilateral posterior crossbite without premature contacts and functional mandibular shifts and with transverse maxillary deficiency. The criteria for sample exclusion included the presence of painful symptoms, facial trauma history, systemic diseases such as juvenile rheumatoid arthritis, mouth opening limitation (< 40 mm, congenital or genetic anomalies, and skeletal asymmetries that may result in TMJ disorders. Dimensional measurements of the condyles between the right and left sides and crossed and non-crossed sides in sagittal and coronal view were made. There was no significant difference between the measurements of the crossed and non-crossed sides in both sagittal and coronal view. These findings suggest that the presence of unilateral posterior crossbite in children with UPXB did not result in changes between the mandibular condyles in the right and left sides or between the crossed and non-crossed sides in the coronal or sagittal plane.

Feasibility of purely endoscopic intramedullary fixation of mandibular condyle fractures.

Science.gov (United States)

Frake, Paul C; Goodman, Joseph F; Joshi, Arjun S

2015-01-01

The investigators of this study hypothesized that fractures of the mandibular condyle can be repaired using short-segment intramedullary implants and purely endoscopic surgical technique, using a basic science, human cadaver model in an academic center. Endoscopic instrumentation was used through a transoral mucosal incision to place intramedullary implants of 2 cm in length into osteotomized mandibular condyles. The surgical maneuvers that required to insert these implants, including condyle positioning, reaming, implant insertion, and seating of the mandibular ramus, are described herein. Primary outcome was considered as successful completion of the procedure. Ten cadaveric mandibular condyles were successfully repaired with rigid intramedullary internal fixation without the use of external incisions. Both insertion of a peg-type implant and screwing a threaded implant into the condylar head were possible. The inferior portion of the implant remained exposed, and the ramus of the mandible was manipulated into position on the implant using retraction at the sigmoid notch. The results of this study suggest that purely endoscopic repair of fractures of the mandibular condyle is possible by using short-segment intramedullary titanium implants and a transoral endoscopic approach without the need for facial incisions or punctures. The biomechanical advantages of these intramedullary implants, including improved strength and resistance to mechanical failure compared with miniplates, have been recently established. The combination of improved implant design and purely endoscopic technique may allow for improved fixation and reduced surgical- and implant-related morbidity in the treatment of condylar fractures.

Intraoral Approach and Stereolithographic-guided Large Mandibular Reconstruction with Fibula Free Flap

Directory of Open Access Journals (Sweden)

Artur Diaz-Carandell, MD

2014-08-01

Full Text Available Summary: The reconstruction of mandibular defects has always been of great concern, and it still represents a challenge for head-and-neck reconstructive surgeons. The mandible plays a major role in mastication, articulation, swallowing, respiration, and facial contour. Thus, when undertaking mandibular reconstruction, restoration of both function and cosmetics should be considered as the measure of success. Microsurgical reconstruction is the gold-standard method to repair a segmental mandibular defect. Reconstruction of sizeable defects often needs a large neck incision, leading to unsatisfactory cosmetic outcomes. Virtual surgical planning and stereolithographic modeling are new techniques that offer excellent results and can provide precise data for mandibular reconstruction and improve postoperative outcomes. We present a case of complete intraoral resection and reconstruction of a large ameloblastoma of the mandible.

Possible interaction between myxomatosis and calicivirosis related to rabbit haemorrhagic disease affecting the European rabbit.

Science.gov (United States)

Marchandeau, S; Bertagnoli, S; Peralta, B; Boucraut-Baralon, C; Letty, J; Reitz, F

2004-11-06

Serological data on myxoma virus, rabbit haemorrhagic disease (RHD) virus and RHD-like viruses in juvenile rabbits (Oryctolagus cuniculus) trapped in 1995, 1996 and 1997 in two areas of France were analysed. For each disease, the effects of bodyweight, year, month and seropositivity for the other disease were modelled by using logistic regressions. In one area, a model including RHD seropositivity was selected to explain the myxoma virus seropositivity. Models including myxoma virus seropositivity were selected to explain the RHD seropositivity in both areas, and the odds of a rabbit being seropositive to both viruses were 5.1 and 8.4 times higher than the odds of a rabbit being seronegative to myxoma virus and seropositive to RHD. The year and bodyweight had significant effects for myxomatosis in one area and for RHD in both areas.

Comparison with myocardial perfusion MRI and myocardial perfusion SPECT in the diagnostic performance of coronary artery disease. A meta-analysis

International Nuclear Information System (INIS)

Iwata, Kunihiro; Kubota, Makoto; Ogasawara, Katsuhiko

2008-01-01

We compared the diagnostic abilities of stress myocardial perfusion MRI (myocardial perfusion MRI) and myocardial perfusion single photon emission computed tomography (SPECT), using a meta-analysis method. We investigated the diagnostic abilities of MRI and SPECT in similar subject groups in reports written in English or Japanese. The reports to be used for analysis were selected according to a ''screening standard,'' which was established in advance. After consolidating the data from the selected reports, we compared the integrated odds ratio, the point estimation values of sensibility/specificity, and the summary receiver operating characteristic (ROC) curve. For the analysis, six reports were selected (subjects: 153, coronary-artery target sites: 447). Meta-analysis revealed that the diagnostic ability of myocardial perfusion MRI was superior to that of myocardial perfusion SPECT regarding each of the parameters. This is considered to be supportive evidence of the usefulness of myocardial perfusion MRI. (author)

[Maxillo-facial surgery in skeletal Class II: repercussions on the temporo-mandibular joints].

Science.gov (United States)

Manière-Ezvan, Armelle; Savoldelli, Charles; Busson, Floriant; Oueiss, Arlette; Orthlieb, Jean-Daniel

2016-03-01

These interventions usually aimed at the correction of the skeletal discrepancy by mandibular retrognatism with an advancement of the distal portion of the mandible after mandibular osteotomy. The position of the condyle is determined during the osteosynthesis with miniplates. Condyles are set back in relation with the supine position of the patient and the weakness of his (her) curarized muscle. All studies show that surgery of mandibular advancement causes a lateral, torque and backward movement of the condyles, all harmful to the condyles. Factors that predispose to condylar resorption are "the patient": a woman, young (between 15 and 40), high mandibular angle, with a history of temporo-mandibular disorders and surgical overload applied to the condyles. What are the possible solutions to avoid failures? Patient preparation before surgery and surgery simulation with an articulator, condylar position control during surgery, working with surgeons to achieve a condylar portion stabilization system (with the CAD), quickly set up a mobilization of the mandible by physiotherapy. © EDP Sciences, SFODF, 2016.

Tc-99m DTPA perfusion scintigraphy and color coded duplex sonography in the evaluation of minimal renal allograft perfusion

International Nuclear Information System (INIS)

Bair, H.J.; Platsch, G.; Wolf, F.; Guenter, E.; Becker, D.; Rupprecht, H.; Neumayer, H.H.

1997-01-01

Aim: The clinical impact of perfusion scintigraphy versus color coded Duplex sonography was evaluated, with respect to their potential in assessing minimal allograft perfusion in vitally threatened kidney transplants, i.e. oligoanuric allografts suspected to have either severe rejection or thrombosis of the renal vein or artery. Methods: From July 1990 to August 1994 the grafts of 15 out of a total of 315 patients were vitally threatened. Technetium-99m DTPA scintigraphy and color coded Duplex sonography were performed in all patients. For scintigraphic evaluation of transplant perfusion analog scans up to 60 min postinjection, and time-activity curves over the first 60 sec after injection of 370-440 MBq Tc-99m diethylenetriaminepentaacetate acid (DTPA) were used and classified by a perfusion score, the time between renal and iliac artery peaks (TDiff) and the washout of the renogram curve. Additionally, evaluation of excretion function and assessment of vascular or urinary leaks were performed. By color coded Duplex sonography the perfusion in all sections of the graft as well as the vascular anastomoses were examined and the maximal blood flow velocity (Vmax) and the resistive index (RI) in the renal artery were determined by means of the pulsed Doppler device. Pathologic-anatomical diagnosis was achieved by either biopsy or post-explant histology in all grafts. Results: Scintigraphy and color coded Duplex sonography could reliably differentiate minimal (8/15) and not perfused (7/15) renal allografts. The results were confirmed either by angiography in digital subtraction technique (DSA) or the clinical follow up. Conclusion: In summary, perfusion scintigraphy and color coded Duplex sonography are comparable modalities to assess kidney graft perfusion. In clinical practice scintigraphy and colorcoded Doppler sonography can replace digital subtraction angiography in the evaluation of minimal allograft perfusion. (orig.) [de

Normal anatomy of lung perfusion SPECT scintigraphy

International Nuclear Information System (INIS)

Moskowitz, G.W.; Levy, L.M.

1987-01-01

Ten patients studies for possible pulmonary embolic disease had normal lung perfusion planar and SPECT scintigraphy. A computer program was developed to superimpose the CT scans on corresponding SPECT images. Superimposition of CT scans on corresponding SPECT transaxial cross-sectional images, when available, provides the needed definition and relationships of adjacent organs. SPECT transaxial sections provide clear anatomic definition of perfusion defects without foreground and background lung tissue superimposed. The location, shape, and size of the perfusion defects can be readily assessed by SPECT. An algorithm was developed for the differentiation of abnormal pulmonary perfusion patterns from normal structures on variation

Regional cortical hyper perfusion on perfusion CT during postical motor deficit: A case report

Energy Technology Data Exchange (ETDEWEB)

Baik, Hye Jin [Dept. of Radiology, Haeundae Paik Hospital, Inje University College of Medicine, Busan (Korea, Republic of)

2013-08-15

Postictal neurologic deficit is a well-known complication mimicking the manifestation of a stroke. We present a case of a patient with clinical evidence of Todd's paralysis correlating with reversible postictal parenchymal changes on perfusion CT and magnetic resonance (MR) imaging. In this case, perfusion CT and MR imaging were helpful in the differential diagnosis of stroke-mimicking conditions.

Ventilation and perfusion display in a single image

International Nuclear Information System (INIS)

Lima, J.J.P. de; Botelho, M.F.R.; Pereira, A.M.S.; Rafael, J.A.S.; Pinto, A.J.; Marques, M.A.T.; Pereira, M.C.; Baganha, M.F.; Godinho, F.

1991-01-01

A new method of ventilation and perfusion display onto a single image is presented. From the data on regions of interest of the lungs, three-dimensional histograms are created, containing as parameters X and Y for the position of the pixels, Z for the perfusion and colour for local ventilation. The perfusion value is supplied by sets of curves having Z proportional to the local perfusion count rate. Ventilation modulates colour. Four perspective views of the histogram are simultaneously displayed to allow visualization of the entire organ. Information about the normal ranges for both ventilation and perfusion is also provided in the histograms. (orig.)

Kinematic Modeling of Normal Voluntary Mandibular Opening and Closing Velocity-Initial Study.

Science.gov (United States)

Gawriołek, Krzysztof; Gawriołek, Maria; Komosa, Marek; Piotrowski, Paweł R; Azer, Shereen S

2015-06-01

Determination and quantification of voluntary mandibular velocity movement has not been a thoroughly studied parameter of masticatory movement. This study attempted to objectively define kinematics of mandibular movement based on numerical (digital) analysis of the relations and interactions of velocity diagram records in healthy female individuals. Using a computerized mandibular scanner (K7 Evaluation Software), 72 diagrams of voluntary mandibular velocity movements (36 for opening, 36 for closing) for women with clinically normal motor and functional activities of the masticatory system were recorded. Multiple measurements were analyzed focusing on the curve for maximum velocity records. For each movement, the loop of temporary velocities was determined. The diagram was then entered into AutoCad calculation software where movement analysis was performed. The real maximum velocity values on opening (Vmax ), closing (V0 ), and average velocity values (Vav ) as well as movement accelerations (a) were recorded. Additionally, functional (A1-A2) and geometric (P1-P4) analysis of loop constituent phases were performed, and the relations between the obtained areas were defined. Velocity means and correlation coefficient values for various velocity phases were calculated. The Wilcoxon test produced the following maximum and average velocity results: Vmax = 394 ± 102, Vav = 222 ± 61 for opening, and Vmax = 409 ± 94, Vav = 225 ± 55 mm/s for closing. Both mandibular movement range and velocity change showed significant variability achieving the highest velocity in P2 phase. Voluntary mandibular velocity presents significant variations between healthy individuals. Maximum velocity is obtained when incisal separation is between 12.8 and 13.5 mm. An improved understanding of the patterns of normal mandibular movements may provide an invaluable diagnostic aid to pathological changes within the masticatory system. © 2014 by the American College of Prosthodontists.

Unusal canal configuration in maxillary and mandibular second molars

Directory of Open Access Journals (Sweden)

Ramachandran Ragunathan

2016-01-01

Full Text Available This clinical article describes three different case reports of maxillary and mandibular second molars with the unusual anatomy of single root with a single canal and their endodontic management. An unusual case of bilateralism is observed in the first two cases in the form of single-rooted second mandibular molars in both the quadrant of the same patient. The presence of maxillary second molar with single root and single canal in the third case is unusual.

Root and Canal Morphology of Mandibular Third Molars in an Iranian Population

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Maryam Kuzekanani

2012-06-01

Full Text Available Background and aims. A through knowledge of the root canal morphology is required for successful endodontic therapy. The aim of this study was to investigate the root and canal morphology of mandibular third molars in Kerman, a province in southeast of Iran. Materials and methods. One-hundred-fifty extracted mandibular third molars were collected randomly from different dental clinics in Kerman. The root canal anatomy and morphology of each tooth was carefully studied using a clearing technique. Root number and morphology, number of canals per root, root canal configuration according to Vertucci classification, and incidence of dilacerated roots and C-shaped canals in mandibular third molars were evaluated under stereomicroscope with ×2 to ×3 magnifications. Results. From the total of 150 mandibular third molars studied, 21% had one root. The majority of teeth (73% had two roots. 5.5% of the teeth had three roots. The incidence of C-shaped canal was 3.5% in this study and 8% of the teeth had at least one dilacerated root. Conclusion. Although root canal anatomy and morphology of mandibular third molars is very variable having two roots seems to be the normal anatomy for these teeth.

A case of low success of blind vaccination campaigns against myxomatosis and rabbit haemorrhagic disease on survival of adult European wild rabbits.

Science.gov (United States)

Rouco, Carlos; Moreno, Sacramento; Santoro, Simone

2016-10-01

Vaccination campaigns against myxomatosis and rabbit haemorrhagic disease (RHD) are commonly used in translocation programs conducted for the purpose of recovering wild European rabbit populations in Iberian Mediterranean ecosystems. In most cases rabbits are vaccinated 'blind' (i.e. without assessing their prior immunological status) for economic and logistic reasons. However, there is conflicting evidence on the effectiveness of such an approach. We tested whether blind vaccination against myxomatosis and rabbit haemorrhagic disease improved rabbit survival in a rabbit translocation program where wild rabbits were kept in semi-natural conditions in three enclosures. We conducted nine capture sessions over two years (2008-2010) and used the information collected to compare the survival of vaccinated (n=511) versus unvaccinated (n=161) adult wild rabbits using capture-mark-recapture analysis. Average monthly survival was no different for vaccinated versus unvaccinated individuals, both in the period between release and first capture (short-term) and after the first capture onward (long-term). Rabbit survival was lower in the short term than in the long term regardless of whether rabbits were vaccinated or not. Lower survival in the short-term could be due to the stress induced by the translocation process itself (e.g. handling stress). However, we did not find any overall effect of vaccination on survival which could be explained by two non-exclusive reasons. First, interference of the vaccine with the natural antibodies in the donor population. Due to donor populations have high density of rabbits with, likely, high prevalence of antibodies as a result of previous natural exposure to these diseases. Second, the lack of severe outbreaks during the study period. Based on our findings we argue that blind vaccination of adult rabbits in translocation programs may be often mostly ineffective and unnecessarily costly. In particular, since outbreaks are hard to predict

Superolateral dislocation of an intact mandibular condyle into the temporal fossa: case report and literature review.

Science.gov (United States)

Sharma, Divashree; Khasgiwala, Ankit; Maheshwari, Bharat; Singh, Charanpreet; Shakya, Neelam

2017-02-01

Temporomandibular joint dislocation refers to the dislodgement of mandibular condyle from the glenoid fossa. Anterior and anteromedial dislocations of the mandibular condyle are frequently reported in the literature, but superolateral dislocation is a rare presentation. This report outlines a case of superolateral dislocation of an intact mandibular condyle that occurred in conjunction with an ipsilateral mandibular parasymphysis fracture. A review of the clinical features of superolateral dislocation of the mandibular condyle and the possible techniques of its reduction ranging from the most conservative means to extensive surgical interventions is presented. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Characterization of Pasteurella multocida involved in rabbit infections

DEFF Research Database (Denmark)

Massacci, Francesca Romana; Magistrali, Chiara Francesca; Cucco, Lucilla

2018-01-01

In rabbit, P. multocida is considered a predominant pathogenic agent; despite this, few data on the molecular epidemiology are available so far. The aim of this work was to characterize P. multocida isolates from rabbit affected by various diseases in Italy. Comparison was made to reference strains...... belonged to the LPS genotypes 3 (22/39) or 6 (17/39). The clonal relationships of the Italian strains from rabbit had similarity to previously reported rabbit isolates that belonged to ST9, ST74, ST204 and ST206, however, they differed from other rabbit references strains that belonged to six other STs....... In particular, ST9 with capsular type F has been previously reported from diseased rabbit in Czech Republic and ST74 has been observed for older rabbit isolates. ST50 has probably been reported from Spain. ST9 and ST50 have previously also been reported from birds and pig, respectively, whereas ST74 has...

Efectos de los aparatos propulsores mandibulares fijos en la articulación temporomandibular

OpenAIRE

Palomino-Gómez, Sandra Patricia [UNESP; Almeida, Kélei Mathias [UNESP; Melllo, Patricia Bicalho de [UNESP; Restrepo, Manuel [UNESP; Raveli, Dirceu Barnabé [UNESP

2014-01-01

Fixed mandibular propulsion appliances are an alternative for the treatment of Class II malocclusion in individuals with mandibular deficiency. Since they are fixed appliances, said devices keep the mandible in an anterior-forced position during rest and during all mandibular functions. When a propulsive appliance is used, the lower jaw is displaced forward and downward. This movement leads to a new position of the condyle, which can, ultimately affect the normal functioning of the temporoman...

Quantitative analysis of the Ca2+ -dependent regulation of delayed rectifier K+ current IKs in rabbit ventricular myocytes.

Science.gov (United States)

Bartos, Daniel C; Morotti, Stefano; Ginsburg, Kenneth S; Grandi, Eleonora; Bers, Donald M

2017-04-01

[Ca 2+ ] i enhanced rabbit ventricular slowly activating delayed rectifier K + current (I Ks ) by negatively shifting the voltage dependence of activation and slowing deactivation, similar to perfusion of isoproterenol. Rabbit ventricular rapidly activating delayed rectifier K + current (I Kr ) amplitude and voltage dependence were unaffected by high [Ca 2+ ] i . When measuring or simulating I Ks during an action potential, I Ks was not different during a physiological Ca 2+ transient or when [Ca 2+ ] i was buffered to 500 nm. The slowly activating delayed rectifier K + current (I Ks ) contributes to repolarization of the cardiac action potential (AP). Intracellular Ca 2+ ([Ca 2+ ] i ) and β-adrenergic receptor (β-AR) stimulation modulate I Ks amplitude and kinetics, but details of these important I Ks regulators and their interaction are limited. We assessed the [Ca 2+ ] i dependence of I Ks in steady-state conditions and with dynamically changing membrane potential and [Ca 2+ ] i during an AP. I Ks was recorded from freshly isolated rabbit ventricular myocytes using whole-cell patch clamp. With intracellular pipette solutions that controlled free [Ca 2+ ] i , we found that raising [Ca 2+ ] i from 100 to 600 nm produced similar increases in I Ks as did β-AR activation, and the effects appeared additive. Both β-AR activation and high [Ca 2+ ] i increased maximally activated tail I Ks , negatively shifted the voltage dependence of activation, and slowed deactivation kinetics. These data informed changes in our well-established mathematical model of the rabbit myocyte. In both AP-clamp experiments and simulations, I Ks recorded during a normal physiological Ca 2+ transient was similar to I Ks measured with [Ca 2+ ] i clamped at 500-600 nm. Thus, our study provides novel quantitative data as to how physiological [Ca 2+ ] i regulates I Ks amplitude and kinetics during the normal rabbit AP. Our results suggest that micromolar [Ca 2+ ] i , in the submembrane or

Effects of Steroid Hormones on Sex Differences in Cerebral Perfusion.

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Carmen Ghisleni

Full Text Available Sex differences in the brain appear to play an important role in the prevalence and progression of various neuropsychiatric disorders, but to date little is known about the cerebral mechanisms underlying these differences. One widely reported finding is that women demonstrate higher cerebral perfusion than men, but the underlying cause of this difference in perfusion is not known. This study investigated the putative role of steroid hormones such as oestradiol, testosterone, and dehydroepiandrosterone sulphate (DHEAS as underlying factors influencing cerebral perfusion. We acquired arterial spin labelling perfusion images of 36 healthy adult subjects (16 men, 20 women. Analyses on average whole brain perfusion levels included a multiple regression analysis to test for the relative impact of each hormone on the global perfusion. Additionally, voxel-based analyses were performed to investigate the sex difference in regional perfusion as well as the correlations between local perfusion and serum oestradiol, testosterone, and DHEAS concentrations. Our results replicated the known sex difference in perfusion, with women showing significantly higher global and regional perfusion. For the global perfusion, DHEAS was the only significant predictor amongst the steroid hormones, showing a strong negative correlation with cerebral perfusion. The voxel-based analyses revealed modest sex-dependent correlations between local perfusion and testosterone, in addition to a strong modulatory effect of DHEAS in cortical, subcortical, and cerebellar regions. We conclude that DHEAS in particular may play an important role as an underlying factor driving the difference in cerebral perfusion between men and women.

The application of the Risdon approach for mandibular condyle fractures.

Science.gov (United States)

Nam, Seung Min; Lee, Jang Hyun; Kim, Jun Hyuk

2013-07-06

Many novel approaches to mandibular condyle fracture have been reported, but there is a relative lack of reports on the Risdon approach. In this study, the feasibility of the Risdon approach for condylar neck and subcondylar fractures of the mandible is demonstrated. A review of patients with mandibular condylar neck and subcondylar fractures was performed from March 2008 to June 2012. A total of 25 patients, 19 males and 6 females, had 14 condylar neck fractures and 11 subcondylar fractures. All of the cases were reduced using the Risdon approach. For subcondylar fractures, reduction and fixation with plates was done under direct vision. For condylar neck fractures, reduction and fixation was done with the aid of a trochar in adults and a percutaneous threaded Kirschner wire in children. There were no malunions or nonunions revealed in follow-up care. Mild transient neuropraxia of the marginal mandibular nerve was seen in 4 patients, which was resolved within 1-2 months. The Risdon approach is a technique for reducing the condylar neck and subcondylar fractures that is easy to perform and easy to learn. Its value in the reduction of mandibular condyle fractures should be emphasized.

[Longitudinal genetic effects on mandibular position of female twins from six to twelve years old].

Science.gov (United States)

Zhu, Chang-feng; Peng, Jing

2013-06-01

To find the longitudinal genetic effects on mandibular position in mixed dentition. The sample used in this study consisted of lateral cephalograms of eighty-nine pairs of female twins in Beijing. With a mixed longitudinal method, the effective twins were 183 pairs(monozygous 110 pairs and dizygous 73 ones). The genetic and environmental effects on mandibular position were analyzed by statistical methods in female twins from six to twelve years old. Statistical comparisons revealed significant (Pchin is the most subjective to environment change, then the mandibular angle, and the condyle is the least. Using N and S as references, the environmental influence on heights showed different order from the most to least changeable: The mandibular angle, the condyle and the chin. In later stage of our observation, the mandibular morphology and growth type might be family inherited. For environmental influences plays important roles on mandibular position, these findings can be used in orthodontic treatment planning.

The visibility of mandibular canal on orthoradial and oblique CBCT slices at molar implant sites

International Nuclear Information System (INIS)

Alkhader, Mustafa; Jarab, Fadi; Shaweesh, Ashraf; Hudieb, Malik

2016-01-01

The aim of the present study was to compare visibility of the mandibular canal on cone beam computed tomography (CBCT)-based orthoradial and oblique slices at molar implant sites. CBCT images for 132 mandibular molar implant sites were selected for the study. After generating orthoradial and oblique slices, two observers evaluated the visibility of the mandibular canal using three-point scoring scale (1-3, good to excellent). Wilcoxon signed-rank test compared the visibility scores of the two slices. Both orthoradial and oblique slices obtained from CBCT had only very good to excellent mandibular canal visibility scores. At 114 mandibular molar implant sites, the visibility score was equal on both orthoradial and oblique slices. Although the visibility score was higher on orthoradial slices for 12 implant sites, the visibility score was higher for six implant sites on oblique slices and the difference was not significant. Therefore, the visibility of the mandibular canal was excellent and comparable on most of orthoradial and oblique slices obtained from CBCT images

CT perfusion of the liver during selective hepatic arteriography. Pure arterial blood perfusion of liver tumor and parenchyma

International Nuclear Information System (INIS)

Komemushi, Atsushi; Tanigawa, Noboru; Kojima, Hiroyuki; Kariya, Shuji; Sawada, Satoshi

2003-01-01

The purpose of this study was to quantify pure arterial blood perfusion of liver tumor and parenchyma by using CT perfusion during selective hepatic arteriography. A total of 44 patients underwent liver CT perfusion study by injection of contrast medium via the hepatic artery. CT-perfusion parameters including arterial blood flow, arterial blood volume, and arterial mean transit time in the liver parenchyma and liver tumor were calculated using the deconvolution method. The CT-perfusion parameters and vascularity of the tumor were compared. A complete analysis could be performed in 36 of the 44 patients. For liver tumor and liver parenchyma, respectively, arterial blood flow was 184.6±132.7 and 41.0±27.0 ml/min/100 g, arterial blood volume was 19.4±14.6 and 4.8±4.2 ml/100 g, and arterial mean transit time was 8.9±4.2 and 10.2±5.3 sec. Arterial blood flow and arterial blood volume correlated significantly with the vascularity of the tumor; however no correlation was detected between arterial mean transit time and the vascularity of the tumor. This technique could be used to quantify pure hepatic arterial blood perfusion. (author)

Parasitic infections of wild rabbits and hares

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Ilić Tamara

2014-01-01

Full Text Available The paper presents the most important parasitic infections of wild rabbits and hares, which harmful effect in this animal population is manifested as a gradual weakening of the immune system, reduction in fertility, weight loss and constant exhaustion. Order of Lagomorpha (hares or lagomorphs belongs to superorder of higher mammals which includes the family of rabbits (Leporidae which are represented in Europe as well as the family of whistleblowers (Ochotonidae which live only in North America and Northern regions of Asia. The most important representatives of Leporidae family are European hare (Lepus europeus and wild rabbit (Oryctolagus cuniculus. The most important endoparasitosis of hares and wild rabbits are: coccidiosis, encephalitozoonosis (nosemosis, toxoplasmosis, sarcocystosis, giardiasis, cryptosporidiosis, protostrongylosis, trichostrngylodosis, passalurosis, anoplocephalidosis, cysticercosis and fasciolosis. The most frequent ectoparasites of rabbits and wild hares are fleas, lice and ticks. Reduction in hare population, which is noticed in whole Europe including Serbia, is caused by changed living conditions, quantitatively and qualitatively insufficient nutrition, increased use of herbicides as well as various infectious diseases and the diseases of parasitic etiology. Since wild rabbits and hares pose a threat to health of domestic rabbits and people, knowledge of parasitic fauna of these wild animals is of extreme epizootiological and epidemiological importance.

Welfare aspects in rabbit rearing and transport

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Claudio Cavani

2010-01-01

Full Text Available The review starts with the description of the rabbits’ (Oryctolagus cuniculus main habits and the current situation concerning the rabbit husbandry and management systems, as well as their effects on the welfare of these animals. As far as the intensive rabbit husbandry systems are concerned, the main problems are related to the time since rabbits have been domesticated and their adaptive capacity and coping styles as respects the farming environment and management systems. Both these aspects have implications in the present and future of rabbit rearing for different purposes. Examples are given on the effects of different housing and management systems on rabbit welfare, as well as examples of the ethological, physiological and productive indicators used to evaluate these effects. Transportation and, more generally, preslaughter phases including catching, fasting and lairage at the abattoir are considered major stressors for farmed rabbits and might have deleterious effects on health, well-being, performance, and finally, product quality. A general statement of the recent scientific studies considering the effects of pre-slaughter factors on physiological and productive measurements are reported. Finally, some indications in order to improve rabbit welfare, already present at the European level, are also outlined, together with the European Food Safety Authority opinions.

Quantitative perfusion imaging in magnetic resonance imaging

International Nuclear Information System (INIS)

Zoellner, F.G.; Gaa, T.; Zimmer, F.; Ong, M.M.; Riffel, P.; Hausmann, D.; Schoenberg, S.O.; Weis, M.

2016-01-01

Magnetic resonance imaging (MRI) is recognized for its superior tissue contrast while being non-invasive and free of ionizing radiation. Due to the development of new scanner hardware and fast imaging techniques during the last decades, access to tissue and organ functions became possible. One of these functional imaging techniques is perfusion imaging with which tissue perfusion and capillary permeability can be determined from dynamic imaging data. Perfusion imaging by MRI can be performed by two approaches, arterial spin labeling (ASL) and dynamic contrast-enhanced (DCE) MRI. While the first method uses magnetically labelled water protons in arterial blood as an endogenous tracer, the latter involves the injection of a contrast agent, usually gadolinium (Gd), as a tracer for calculating hemodynamic parameters. Studies have demonstrated the potential of perfusion MRI for diagnostics and also for therapy monitoring. The utilization and application of perfusion MRI are still restricted to specialized centers, such as university hospitals. A broad application of the technique has not yet been implemented. The MRI perfusion technique is a valuable tool that might come broadly available after implementation of standards on European and international levels. Such efforts are being promoted by the respective professional bodies. (orig.) [de

Perfusion-weighted MR imaging of uterine leiomyoma

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Takase, Hiroyasu; Munechika, Hirotsugu [Showa Univ., Tokyo (Japan). School of Medicine

2001-06-01

Serial images of uterine leiomyoma in gradient-echo, echo-planar, magnetic resonance imaging were taken to draw a {delta}R2{sup *} curve after intravenous bolus injection of Gd-DTPA. The {delta}R2{sup *} integral was calculated from a {delta}R2{sup *} curve to have relative perfusion of uterine leiomyoma. We then, evaluated the amount of perfusion correlated with MR findings, size and number of leiomyoma or the clinical symptoms and established that perfusion was correlated positively with the findings of T2 weighted images and clinical symptoms but not with other MR findings or size and number of leiomyoma. In conclusion, we presumed that the clinical symptoms could be reduced by decreasing of an amount of perfusion of uterine leiomyoma in some means. However, it remained uncertain why severe clinical symptoms were associated with a high amount of perfusion in uterine leiomyomas. (author)

Meta-analysis of skeletal mandibular changes during Frankel appliance treatment.

Science.gov (United States)

Perillo, Letizia; Cannavale, Rosangela; Ferro, Fabrizia; Franchi, Lorenzo; Masucci, Caterina; Chiodini, Paolo; Baccetti, Tiziano

2011-02-01

The purpose of this study was to perform a meta-analysis of articles to verify the mandibular changes produced by the Fränkel-2 (FR-2) appliance during the treatment of growing patients with Class II malocclusions when compared with untreated growing Class II subjects. The literature published from January 1966 to January 2009 was reviewed with search engines. A quality analysis was performed. The effects on primary end points were calculated with random-effect models. Heterogeneity was assessed using Q statistic and investigated using study-level meta-regression. A total of nine articles were identified. The quality of the studies ranged from low to medium. Meta-analysis showed that the FR-2 was associated with enhancement of mandibular body length [0.4 mm/year 95 per cent confidence interval (CI) 0.182-0.618], total mandibular length (1.069 mm/year, 95 per cent CI 0.683-1.455), and mandibular ramus height (0.654 mm/year, 95 per cent CI 0.244-1.064). A consistent heterogeneity among studies was found for all the considered linear measurements. The FR-2 appliance had a statistically significant effect on mandibular growth. Nevertheless, the heterogeneity of the FR-2 effects, the quality of studies, the differences in age, skeletal age, treatment duration, and the inconsistent initial diagnosis seem to overstate the benefits of the FR-2 appliance. An evidence-based approach to the orthodontic outcomes of FR-2 appliance is needed, by selecting and comparing groups of children with the same cephalometric characteristics with and without treatment.

Blood Profile of Rabbits Infected with Eimeria magna

Directory of Open Access Journals (Sweden)

A Hana

2011-09-01

Full Text Available Abstract. The research aimed at determining the blood profile of local rabbits infected with different dose of Eimeria magna oocysts. This research used 45 male rabbits with the age of 4 month old, range from 1.5 to 1.8 kg, clinically healthy and free from coccidiosis. The rabbits were randomly divided into 3 groups, group I as control (K-0 was given 1.0 ml distilled water/rabbit orally, group II (K-10 was infected with single dose of 10x106 oocysts of E. magna/rabbit orally, and group III (K-20 was infected with single dose of 20x106 oocysts of E. magna/rabbit orally. After infection, rabbits were examined for clinical signs, body weight and temperature daily for five days. Blood samples were drawn from the vena marginalis to examine the number of erythrocytes, hemoglobine, packed cell volume (PCV, leukocytes and its deferent, total protein plasma (TPP and fibrinogen, activities of alkaline phosphatase (ALP, alanine amino transferase (ALT, and aspartat aminotransferase (AST. The data were statistically analyzed by two-way anova using factorial design. The results of this research showed that the infection of E. magna in rabbits caused fever and weight loss, accompanied by normochromic microcytic anemia (at doses of 10x106 oocysts, macrocytic normochromic (at doses of 20x106 oocysts, leukocytosis, lymphocytosis, hiperfibrinogenemia, and increased of ALP activity. There were correlations between clinical symptoms and blood profile of rabbits infected with E. magna for five days. The higher the dose and the longer the infection of E. magna in rabbits caused weight loss, increased body temperature, MCV (microcytic to macrocytic, leukocyte, fibrinogen and ALP activity. These findings were useful to have a better understanding of pathophysiology of E. magna infection in  rabbits. Key Words: Eimeria magna, oocyst, rabbit, blood profile A Hana et al/Animal Production 13(3:185-190 (2011

Changes in the edentulous maxilla in persons wearing implant-retained mandibular overdentures

NARCIS (Netherlands)

Narhi, TO; Geertman, ME; Hevinga, M; Abdo, H; Kalk, W

Statement of problem. It has been suggested that risk for severe resorption in the anterior maxilla is increased in persons wearing mandibular implant-retained overdentures. However, little information is available about the changes in the edentulous maxilla after mandibular implant treatment.

[Orthodontic Management of the Impacted Mandibular Second Molar Tooth].

Science.gov (United States)

Mah, Michael; Takada, Kenji

2016-09-01

When the mandibular permanent second molar becomes impacted, it is identified as a malocclusion that needs treatment as it often leads to unwanted complications such as caries and periodontitis of the adjacent permanent first molar. Other less common complications include root resorption of the adjacent first molar root or continued root development to be in close proximity to the inferior dental alveolar nerve. This paper seeks to differentiate various levels of severity of impaction and review treatment options that are considered clinically available for the proper management of the impacted mandibular permanent second molar. Treatment options that will be discussed in this article include timing of second molar removal for replacement by the third molar, relief of impaction via second premolar removal, surgical repositioning and the combination of third molar removal, surgical exposure and orthodontic uprighting of the impacted tooth. Depending on the severity of the impaction, most impactions can be easily and predictably corrected with nickel titanium archwires or auxillary open coil springs or uprighting springs. Uncommonly, the mandibular permanent second molar can become severely impacted and in close proximity to the inferior dentoalveolar nerve. In these instances, the use of temporary anchorage devices such as microimplants has shown to be successful in uprighting the severely impacted mandibular permanent second molars. © EDP Sciences, SFODF, 2016.

Regional myocardial perfusion of cardioplegic solutions

International Nuclear Information System (INIS)

Eugene, J.; Lyons, K.P.; Ott, R.A.; Gelezunas, V.L.; Chang, C.W.; Kowall, M.G.; Haiduc, N.J.

1987-01-01

We compared the regional myocardial perfusion of blood cardioplegic solution (BCP) and crystalloid cardioplegic solution (CCP) in 14 mongrel dogs. Cardiopulmonary bypass was established at 28 degrees C, and a hydraulic occluder was placed around the proximal left anterior descending (LAD) coronary artery. In group 1 (N = 7) collateral coronary arteries were ligated; in group 2 (N = 7) collateral coronary arteries were left in situ. After the aorta was clamped, BCP and CCP were alternately perfused at 200 ml/min. The occluder was inflated to produce moderate, severe, and critical LAD stenosis, and regional perfusion was measured by xenon-133 washout with the Silicon Avalanche Radiation Detector. BCP infusion produced a consistently higher aortic pressure, but CCP flow was better than BCP flow under all conditions, particularly without coronary collaterals. Regional myocardial perfusion of CCP is superior to BCP

Protection against myxomatosis and rabbit viral hemorrhagic disease with recombinant myxoma viruses expressing rabbit hemorrhagic disease virus capsid protein.

Science.gov (United States)

Bertagnoli, S; Gelfi, J; Le Gall, G; Boilletot, E; Vautherot, J F; Rasschaert, D; Laurent, S; Petit, F; Boucraut-Baralon, C; Milon, A

1996-08-01

Two myxoma virus-rabbit hemorrhagic disease virus (RHDV) recombinant viruses were constructed with the SG33 strain of myxoma virus to protect rabbits against myxomatosis and rabbit viral hemorrhagic disease. These recombinant viruses expressed the RHDV capsid protein (VP60). The recombinant protein, which is 60 kDa in size, was antigenic, as revealed by its reaction in immunoprecipitation with antibodies raised against RHDV. Both recombinant viruses induced high levels of RHDV- and myxoma virus-specific antibodies in rabbits after immunization. Inoculations by the intradermal route protected animals against virulent RHDV and myxoma virus challenges.

Consideration of Normal Variation of Perfusion Measurements in the Quantitative Analysis of Myocardial Perfusion SPECT: Usefulness in Assessment of Viable Myocardium

International Nuclear Information System (INIS)

Paeng, Jin Chul; Lim, Il Han; Kim, Ki Bong; Lee, Dong Soo

2008-01-01

Although automatic quantification software of myocardial perfusion SPECT provides highly objective and reproducible quantitative measurements, there is still some limitation in the direct use of quantitative measurements. In this study we derived parameters using normal variation of perfusion measurements, and tried to test the usefulness of these parameters. In order to calculate normal variation of perfusion measurements on myocardial perfusion SPECT, 55 patients (M:F=28:27) of low-likelihood for coronary artery disease were enrolled and 201 Tl rest / 99m Tc-MIBI stress SPECT studies were performed. Using 20-segment model, mean (m) and standard deviation (SD) of perfusion were calculated in each segment. As a myocardial viability assessment group, another 48 patients with known coronary artery disease, who underwent coronary artery bypass graft surgery (CABG) were enrolled. 201 Tl rest / 99m Tc-MIBI stress / 201 Tl 24-hr delayed SPECT was performed before CABG and SPECT was followed up 3 months after CABG. From the preoperative 24-hr delayed SPECT, Q delay (perfusion measurement), Δ delay (Q delay .m) and Z delay ((Q delay .m)/SD) were defined and diagnostic performances of them for myocardial viability were evaluated using area under curve (AUC) on receiver operating characteristic (ROC) curve analysis. Segmental perfusion measurements showed considerable normal variations among segments. In men, the lowest segmental perfusion measurement was 51.8±6.5 and the highest segmental perfusion was 87.0±5.9, and they are 58.7±8.1 and 87.3±6.0, respectively in women. In the viability assessment, Q delay showed AUC of 0.633, while those for Δ delay and Z delay were 0.735 and 0.716, respectively. The AUCs of Δ delay and Z delay were significantly higher than that of Q delay (p=0.001 and 0.018, respectively). The diagnostic performance of Δ delay , which showed highest AUC, was 85% of sensitivity and 53% of specificity at the optimal cutoff of -24.7. On automatic

Increased sinusoidal volume and solute extraction during retrograde liver perfusion

International Nuclear Information System (INIS)

Bass, N.M.; Manning, J.A.; Weisiger, R.A.

1989-01-01

Retrograde isolated liver perfusion has been used to probe acinar functional heterogeneity, but the hemodynamic effects of backward flow have not been characterized. In this study, extraction of a long-chain fatty acid derivative, 12-N-methyl-7-nitrobenzo-2-oxa-1,3-diazol-amino stearate (12-NBDS), was greater during retrograde than during anterograde perfusion of isolated rat liver. To determine whether hemodynamic differences between anterograde and retrograde perfused livers could account for this finding, the hepatic extracellular space was measured for both directions of flow by means of [ 14 C]sucrose washout during perfusion as well as by direct measurement of [ 14 C]sucrose entrapped during perfusion. A three- to fourfold enlargement of the total hepatic extracellular space was found during retrograde perfusion by both approaches. Examination of perfusion-fixed livers by light microscopy and morphometry revealed that marked distension of the sinusoids occurred during retrograde perfusion and that this accounts for the observed increase in the [ 14 C]sucrose space. These findings support the hypothesis that maximum resistance to perfusate flow in the isolated perfused rat liver is located at the presinusoidal level. In addition, increased transit time of perfusate through the liver and greater sinusoidal surface area resulting from sinusoidal distension may account for the higher extraction of 12-NBDS and possibly other compounds by retrograde perfused liver

Submillimeter Diameter Poly(Vinyl Alcohol) Vascular Graft Patency in Rabbit Model

Science.gov (United States)

Cutiongco, Marie F. A.; Kukumberg, Marek; Peneyra, Jonnathan L.; Yeo, Matthew S.; Yao, Jia Y.; Rufaihah, Abdul Jalil; Le Visage, Catherine; Ho, Jackie Pei; Yim, Evelyn K. F.

2016-01-01

Microvascular surgery is becoming a prevalent surgical practice. Replantation, hand reconstruction, orthopedic, and free tissue transfer procedures all rely on microvascular surgery for the repair of venous and arterial defects at the millimeter and submillimeter levels. Often, a vascular graft is required for the procedure as a means to bridge the gap between native arteries. While autologous vessels are desired for their bioactivity and non-thrombogenicity, the tedious harvest process, lack of availability, and caliber or mechanical mismatch contribute to graft failure. Thus, there is a need for an off-the-shelf artificial vascular graft that has low thrombogenic properties and mechanical properties matching those of submillimeter vessels. Poly(vinyl alcohol) hydrogel (PVA) has excellent prospects as a vascular graft due to its bioinertness, low thrombogenicity, high water content, and tunable mechanical properties. Here, we fabricated PVA grafts with submillimeter diameter and mechanical properties that closely approximated those of the rabbit femoral artery. In vitro platelet adhesion and microparticle release assay verified the low thrombogenicity of PVA. A stringent proof-of-concept in vivo test was performed by implanting PVA grafts in rabbit femoral artery with multilevel arterial occlusion. Laser Doppler measurements indicated the improved perfusion of the distal limb after implantation with PVA grafts. Moreover, ultrasound Doppler and angiography verified that the submillimeter diameter PVA vascular grafts remained patent for 2 weeks without the aid of anticoagulant or antithrombotics. Endothelial cells were observed in the luminal surface of one patent PVA graft. The advantageous non-thrombogenic and tunable mechanical properties of PVA that are retained even in the submillimeter diameter dimensions support the application of this biomaterial for vascular replacement in microvascular surgery. PMID:27376059

Hepatic artery perfusion imaging

International Nuclear Information System (INIS)

Thrall, J.H.; Gyves, J.W.; Ziessman, H.A.; Ensminger, W.D.

1985-01-01

Organ and region-selective intra-arterial chemotherapy have been used for more than two decades to treat malignant neoplasms in the extremities, head and neck region, pelvis, liver, and other areas. Substantial evidence of improved response to regional chemotherapy now exists, but there are stringent requirements for successful application of the regional technique. First, the chemotherapeutic agent employed must have appropriate pharmacokinetic and pharmacodynamic properties. Second, the drug must be reliably delivered to the tumor-bearing area. This typically requires an arteriographic assessment of the vascular supply of the tumor, followed by placement of a therapeutic catheter and confirmation that the ''watershed'' perfusion distribution from the catheter truly encompasses the tumor. Optimal catheter placement also minimizes perfusion of nontarget organs. Radionuclide perfusion imaging with technetium 99m-labeled particles, either microspheres or macroaggregates of albumin, has become the method of choice for making these assessments. Catheter placement itself is considered by many to represent a type of ''therapeutic'' intervention. However, once the catheter is in the hepatic artery the radionuclide perfusion technique can be used to assess adjunctive pharmacologic maneuvers designed to further exploit the regional approach to chemotherapy. This chapter presents the technetium Tc 99m macroaggregated albumin method for assessing catheter placement and the pharmacokinetic rationale for regional chemotherapy, and discusses two promising avenues for further intervention

Usefulness of high-resolution sonography in early diagnosis of rabbit clonorchiasis

International Nuclear Information System (INIS)

Lim, Jae Hoon; Choi, Don Gil; Chung, Il Gyu; Phyun, Lae Hyun; Pyeun, Yong Seon; Hong, Sung Tae; Lee, Me Jeong

1999-01-01

To determine the role of high-resolution sonography in the early diagnosis of experimentally induced clonorchiasis in rabbits. We performed sonographic examination weekly in 22 lightly-infected rabbits (10 rabbits infected with 10 metacercariae, 6 rabbits infected with 20 metacercariae, and 6 rabbits infected with 40 metacercariae), and 10 heavily-infected rabbits (500 metacercariae). The sonographic criterion of diagnosis with dilatation of the intrahepatic ducts. We sacrificed lightly-infected rabbits and counted numbers of adult worms of clonorchis sinensis 9 weeks after infection. Sonographic abnormalities were found 3 weeks after infection in 2 lightly-infected rabbits and 5 heavily-infected rabbits. On sonography at 9 weeks after infection, we observed dilatation of the intrahepatic ducts in 11 (65%) of 17 lightly-infected rabbits and all of 10 heavily-infected rabbits. High-resolution sonography is very useful in early diagnosis of rabbits clonorchiasis.

Usefulness of high-resolution sonography in early diagnosis of rabbit clonorchiasis

Energy Technology Data Exchange (ETDEWEB)

Lim, Jae Hoon; Choi, Don Gil; Chung, Il Gyu; Phyun, Lae Hyun; Pyeun, Yong Seon [Sungkyunkwan University College of Medicine, Seoul (Korea, Republic of); Hong, Sung Tae; Lee, Me Jeong [Seoul National University College of Medicine, Seoul (Korea, Republic of)

1999-09-15

To determine the role of high-resolution sonography in the early diagnosis of experimentally induced clonorchiasis in rabbits. We performed sonographic examination weekly in 22 lightly-infected rabbits (10 rabbits infected with 10 metacercariae, 6 rabbits infected with 20 metacercariae, and 6 rabbits infected with 40 metacercariae), and 10 heavily-infected rabbits (500 metacercariae). The sonographic criterion of diagnosis with dilatation of the intrahepatic ducts. We sacrificed lightly-infected rabbits and counted numbers of adult worms of clonorchis sinensis 9 weeks after infection. Sonographic abnormalities were found 3 weeks after infection in 2 lightly-infected rabbits and 5 heavily-infected rabbits. On sonography at 9 weeks after infection, we observed dilatation of the intrahepatic ducts in 11 (65%) of 17 lightly-infected rabbits and all of 10 heavily-infected rabbits. High-resolution sonography is very useful in early diagnosis of rabbits clonorchiasis.

Defibrotide reduces infarct size in a rabbit model of experimental myocardial ischaemia and reperfusion.

Science.gov (United States)

Thiemermann, C.; Thomas, G. R.; Vane, J. R.

1989-01-01

1. Defibrotide, a single-stranded polydeoxyribonucleotide obtained from bovine lungs, has significant anti-thrombotic, pro-fibrinolytic and prostacyclin-stimulating properties. 2. The present study was designed to evaluate the effects of defibrotide on infarct size and regional myocardial blood flow in a rabbit model of myocardial ischaemia and reperfusion. 3. Defibrotide (32 mg kg-1 bolus + 32 mg kg-1 h-1, i.v.) either with or without co-administration of indomethacin (5 mg kg-1 x 2, i.v.) was administered 5 min after occlusion of the left anterior-lateral coronary artery and continued during the 60 min occlusion and subsequent 3 h reperfusion periods. 4. Defibrotide significantly attenuated the ischaemia-induced ST-segment elevation and abolished the reperfusion-related changes (R-wave reduction and Q-wave development) in the electrocardiogram. In addition, defibrotide significantly improved myocardial blood flow in normal and in ischaemic, but not in infarcted sections of the heart. The improvement in blood flow in normal perfused myocardium, but not in the ischaemic area was prevented by indomethacin. 5. Although the area at risk was similar in all animal groups studied, defibrotide treatment resulted in a 51% reduction of infarct size. Indomethacin treatment abolished the reduction of infarct size seen with defibrotide alone. 6. The data demonstrate a considerable cardioprotective effect of defibrotide in the reperfused ischaemic rabbit myocardium. This effect may be related, at least in part, to a stimulation of endogenous prostaglandin formation. Other possible mechanisms are discussed. PMID:2758223

Innate resistance to myxomatosis in wild rabbits in England*

Science.gov (United States)

Ross, J.; Sanders, M. F.

1977-01-01

Wild rabbits (Oryctolagus cuniculus) from one study area in England have been used over a period of 11 years to investigate the possible appearance of innate resistance to myxomatosis. Rabbits of 4-6 weeks old were captured alive, retained in the laboratory until at least 4 months old, and then infected with a type of myxoma virus which kills 90-95% of laboratory rabbits. Observations were made of symptoms, mortality rate and survival times. In the first 4 years of the study (1966-9), mortality rates were not significantly different from those of laboratory rabbits, although survival times of wild rabbits were appreciably longer. In 1970, the mortality rate amongst wild rabbits was 59%, in 1974 it was 17%, and in 1976 it was 20%, thus showing that a considerable degree of inherited resistance to myxomatosis has developed. The types of myxoma virus most commonly isolated from wild rabbits in Great Britain in recent years have been those which cause 70-95% mortality in laboratory rabbits. Therefore, if the degree of innate resistance demonstrated is widespread in Great Britain, there are serious implications regarding the size of the rabbit population, because myxomatosis has been an important factor in holding rabbit numbers at a relatively low level. PMID:270526

Innate resistance to myxomatosis in wild rabbits in England.

Science.gov (United States)

Ross, J; Sanders, M F

1977-12-01

Wild rabbits (Oryctolagus cuniculus) from one study area in England have been used over a period of 11 years to investigate the possible appearance of innate resistance to myxomatosis. Rabbits of 4-6 weeks old were captured alive, retained in the laboratory until at least 4 months old, and then infected with a type of myxoma virus which kills 90-95% of laboratory rabbits. Observations were made of symptoms, mortality rate and survival times.In the first 4 years of the study (1966-9), mortality rates were not significantly different from those of laboratory rabbits, although survival times of wild rabbits were appreciably longer. In 1970, the mortality rate amongst wild rabbits was 59%, in 1974 it was 17%, and in 1976 it was 20%, thus showing that a considerable degree of inherited resistance to myxomatosis has developed.The types of myxoma virus most commonly isolated from wild rabbits in Great Britain in recent years have been those which cause 70-95% mortality in laboratory rabbits. Therefore, if the degree of innate resistance demonstrated is widespread in Great Britain, there are serious implications regarding the size of the rabbit population, because myxomatosis has been an important factor in holding rabbit numbers at a relatively low level.

Clinical and orthopantomographic evaluation of mandibular third molar

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F K Saraswati

2010-01-01

Full Text Available Objective: To evaluate sensitivity of orthopentograph (OPG in assessing the number and morphology of roots of the mandibular third molar. Materials and Methods : The study population consisted of 100 ILTMs (impacted lower third molars ranging from 18 to 42 years with equal sex distribution. All the teeth were subsequently extracted , collected and compared with OPG features for position, numb,er, morphology, and relation to mandibular canal. Conclusion: In conclusion, a large sample study is suggested with techniques like Clark′s and right angle technique which determines the three-dimensional orientation of the impacted teeth.

A randomized clinical trial comparing mandibular incisor proclination produced by fixed labial appliances and clear aligners.

Science.gov (United States)

Hennessy, Joe; Garvey, Thérèse; Al-Awadhi, Ebrahim A

2016-09-01

To compare the mandibular incisor proclination produced by fixed labial appliances and third generation clear aligners. Patients underwent a course of orthodontic treatment using either fixed labial appliances or clear aligners (Invisalign). Mandibular incisor proclination was measured by comparing pretreatment and near-end treatment lateral cephalograms. Eligibility criteria included adult patients with mild mandibular incisor crowding (clear aligner group. Baseline characteristics were similar for both groups: Fixed appliance mean crowding was 2.1 ± 1.3 mm vs clear aligner mean crowding, 2.5 ± 1.3 mm; pretreatment mean mandibular incisor inclination for the fixed appliance group was 90.8 ± 5.4° vs 91.6 ± 6.4° for the clear aligner group. Fixed appliances produced 5.3 ± 4.3° of mandibular incisor proclination. Clear aligners proclined the mandibular incisors by 3.4 ± 3.2°. The difference between the two groups was not statistically significant (P > .05). There was no difference in the amount of mandibular incisor proclination produced by clear aligners and fixed labial appliances in mild crowding cases.

Early Experience with Biodegradable Fixation of Pediatric Mandibular Fractures

OpenAIRE

Mazeed, Ahmed Salah; Shoeib, Mohammed Abdel-Raheem; Saied, Samia Mohammed Ahmed; Elsherbiny, Ahmed

2014-01-01

This clinical study aims to evaluate the stability and efficiency of biodegradable self-reinforced poly-l/dl-lactide (SR-PLDLA) plates and screws for fixation of pediatric mandibular fractures. The study included 12 patients (3–12 years old) with 14 mandibular fractures. They were treated by open reduction and internal fixation by SR-PLDLA plates and screws. Maxillomandibular fixation was maintained for 1 week postoperatively. Clinical follow-up was performed at 1 week, 6 weeks, 3 months, and...

Mandibular Fracture Patterns at a Medical Center in Central Taiwan: A 3-Year Epidemiological Review.

Science.gov (United States)

Lin, Fu-Yu; Wu, Chao-I; Cheng, Hsu-Tang

2017-12-01

Mandibular fractures constitute a major portion of maxillofacial trauma and may lead to considerable functional and aesthetic sequelae if treatment is inadequate or delayed. An epidemiology study on mandibular fractures may guide the preventive efforts of the Taiwan public health care system. Therefore, a retrospective review was conducted at a medical center in central Taiwan to evaluate the current mandibular fracture epidemiology.The medical records and digitized radiographs of 198 patients who received treatment for mandibular fractures during a 3-year period (from October 2010 to September 2013) at a medical center in central Taiwan were reviewed to obtain demographic and injury data.The average age was 29.4 years (3-82 years). Patients aged 21 to 30 years sustained the most mandibular fractures (62 patients, 31.3%). The overall sex distribution (male to female) ratio was 1.8. Motor-vehicle accidents (MVAs) were the most common mechanism of injury (162 patients, 82%), and scooter and motorcycle riders wearing partial-coverage helmets constituted the majority of patients. A chart review identified 198 patients with 335 mandibular fractures; 113 patients (57.1%) had multiple mandibular fractures. The most common fracture sites were the symphysis and parasymphysis regions (38.9%), followed by the condyle (26.0%), angle (14.3%), body (14.3%), and ramus (6.6%).MVAs are the major cause of mandibular fractures in central Taiwan, and patients aged Taiwan. Copyright © 2017 The Authors. Published by Wolters Kluwer Health, Inc. All rights reserved.

Radiation-induced heart disease due to intrathonacic tumor radiotherapy of a single dose to the rabbits' heart

International Nuclear Information System (INIS)

Zhou Weibing; Feng Yan; Chen Jiayi; Luo Quanyong

2007-01-01

Objective: To observe the changes of radiation-induced heart disease (RIHD) in the rabbits irradiated in clinical related dose, and to evaluate the apoptosis and hypoxia in the irradiated heart by the new scintigraphic agents of 99 Tc m -HL91 and 99 Tc m -Annexin V of heart SPECT. Methods: Tenty-four New Zealand white rabbits 4-month old and 2-3 kg by weight were divided into two groups. Group 1 (clinical related dose group): 16 irradiated by a single close from 0 to 18 Gy. Group 2 (high dose group): 8 irradiated dose from 22 to 80 Gy. The serum cTnI/CKMB, ECG, and heart SPECT(using 99 Tc m -MIBI, 99 Tc m -HL91 and 99 Tc m -Annexin V as agents) were detected before and after irradiation. The animals were followed for 5 months. Then biopsy of rabbit heart was performed and pathologic examination was made by H.E. stain. Results: In the 16 rabbits of clinical related dose group, none died of RIHD. Whereas 2 rabbits died of RIHD in the high dose group. One died of myocardial infarction and the other of congestive heart failure. According to the Stewart introduced heart lesion grading system, of the clinical close ann, there were moderate in 1 rabbit, minimal in 14; and of the high dose ann, it was severe in 2, marked in 1, moderate in 5. The parallel relation was observed between the ECG results and the pathological changes (χ 2 =0.08, P=0.771). Serum value of cTnI, was elevated at the 12th hour after irradiation reaching the peak and maintained for 4 months. However, it came down in the 5th month. The difference of serum cTnI value before and after radiation was statistically significant. Myocardial perfusion scintigraphy tested by heart SPECT ( 99 Tc m -MIBI) showed defects was present in all irradiated rabbits. The relationship between the defects and radiation dose or between the defects and the real RIHD was uncertain. The SPECT images displayed that 99 Tc m -HL91 and 99m Tc-Annexin V did not accumulate in the irradiated heart. Conclusions: No serious damage is

Surgical Management of Mandibular Central Incisors with Dumbbell Shaped Periapical Lesion: A Case Report

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Roopadevi Garlapati

2014-01-01

Full Text Available Dental traumatic injuries may affect the teeth and alveolar bone directly or indirectly. Pulpal necrosis and chronic and apical periodontitis with cystic changes are the most common sequelae of the dental traumatic injuries, if the teeth are not treated immediately. This case report focuses on the conventional and surgical management of mandibular central incisors. A twenty-four-year-old male patient presented with pain in the mandibular central incisors. Radiographic examination revealed mandibular central incisors with dumbbell shaped periapical lesion. After root canal treatment, parendodontic surgery was performed for mandibular central incisors. After one-year recall examination, the teeth were asymptomatic and periapical lesion had healed.

Alveolar ridge expansion-assisted orthodontic space closure in the mandibular posterior region.

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Ozer, Mete; Akdeniz, Berat Serdar; Sumer, Mahmut

2013-12-01

Orthodontic closure of old, edentulous spaces in the mandibular posterior region is a major challenge. In this report, we describe a method of orthodontic closure of edentulous spaces in the mandibular posterior region accelerated by piezoelectric decortication and alveolar ridge expansion. Combined piezosurgical and orthodontic treatments were used to close 14- and 15-mm-wide spaces in the mandibular left and right posterior areas, respectively, of a female patient, aged 18 years and 9 months, diagnosed with skeletal Class III malocclusion, hypodontia, and polydiastemas. After the piezoelectric decortication, segmental and full-arch mechanics were applied in the orthodontic phase. Despite some extent of root resorption and anchorage loss, the edentulous spaces were closed, and adequate function and esthetics were regained without further restorative treatment. Alveolar ridge expansion-assisted orthodontic space closure seems to be an effective and relatively less-invasive treatment alternative for edentulous spaces in the mandibular posterior region.

Pharyngeal Airway Space Changes After Condylar Replacement and Mandibular Advancement Surgery.

Science.gov (United States)

Yuen, Holly; Rossouw, P Emile; Wolford, Larry M; Wang, Hongyue

2018-01-03

The aim of this study was to examine the total volume and cross-sectional areas of the pharyngeal airway after bilateral condylar replacement and mandibular advancement surgery. A total of 137 patients (126 women and 11 men) underwent bilateral temporomandibular joint total joint replacement performed by 1 surgeon. A subsample of 30 patients who underwent condylar replacement and only mandibular advancement were evaluated for impact on the airway. Measurements were taken preoperatively, postoperatively, and at a follow-up 1 year after surgery on cone beam computed tomography scans. InVivoDental 3-dimensional imaging (Anatomage, San Jose, CA) was used to measure airway space regarding total volume (in cubic centimeters); minimum cross-sectional area (in square millimeters); minimum cross sections of the first, second, and third cervical vertebrae; and whether the patient had mandibular retrognathia before surgery. A second operator was used to test for interoperator error. Descriptive and bivariate statistics were computed, and the P value was set at .05. There was a significant increase in all measurements at the follow-up visit compared with the preoperative visit. There were no significant differences between groups based on simultaneous Le Fort I surgery, mandibular retrognathia, and gender. However, there were statistically significant differences in cross sections 1 and 2, as well as minimum cross-sectional area, regarding age. Condylar replacement and mandibular advancement have a significant association with an increase in airway space. The intraclass correlation coefficient showed excellent agreement between interoperator measurements. Patients undergoing bilateral temporomandibular joint replacement and mandibular advancement surgery showed an increase in pharyngeal airway space at a 1-year follow-up. In this study, age was significantly associated with the cross-sectional areas of the airway, with older patients having smaller values. Copyright © 2018

The effects of the low calcium diet and irradiation on the mandibular condyle of rats

International Nuclear Information System (INIS)

Ahn, Hee Mun; Lee, Sang Rae

1993-01-01

This study was performed to investigate the changes of mandibular condyle by low diet and the effects of irradiation on the bone in ofteoporotic state. In order to carry out this experiment, 80 served-week old Sprague-Dawley strain rats about 150gm were selected and equally divided into one experimental group of 40 rats and one control group with the remainder. The experimental group and the control group of 40 rats and one control group with the remainder. The experimental group and the control group were then subdivided into two group and exposed to irradiation. The two irradiation groups received a single dose of 20 Gy on the jaw area only and irradiated with a cobalt-60 teletherapy unit. The rats in the control and experimental groups were serially terminated by fours on the 3rd, the 7th, the 14th, and the 21st day after irradiation. After termination, both sides of the dead rats mandibular condyle were removed and fixed with 10% neutral formalin. The bone mineral density of mandibular condle was measured by use of dual energy X-ray with Hitex HA-80 (Hitex Co., Japan). Thereafter, the obtained radiographs were observed, and the mandibular condyle was further decalcified and embedded in paraffin as the general method. The specimen sectioned and stained with hematoxylin-eosin, PAS and Rabbit Anti-Human Tumor Necrosis Factor-α observed by a light microscope. The obtained results were as follows: 1. In the non-irradiated group with low calcium diet, the bone mineral density of the condyle was markedly decreased after 14 days, and decrease the number of trabeculae of the condyle and resorption of the calcified cartilaginous zone were observed after 3 days. On microscopic observation, the number and size of trabecular were decreased after 7 days of experiment. 2. In the irradiated group with the low calcium diet, the bone mineral density of the condyle was markedly decreased after 14 days and resorption of the calcified cartilaginous zone and decrease the number and

[An automatic system controlled by microcontroller for carotid sinus perfusion].

Science.gov (United States)

Yi, X L; Wang, M Y; Fan, Z Z; He, R R

2001-08-01

To establish a new method for controlling automatically the carotid perfusion pressure. A cheap practical automatic perfusion unit based on AT89C2051 micro controller was designed. The unit, LDB-M perfusion pump and the carotid sinus of an animal constituted an automatic perfusion system. This system was able to provide ramp and stepwise updown perfusion pattern and has been used in the research of baroreflex. It can insure the precision and reproducibility of perfusion pressure curve, and improve the technical level in corresponding medical field.

Prevalence of three rooted permanent mandibular first molars in Haryana (North Indian population

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Alpa Gupta

2017-01-01

Full Text Available Background: Mandibular first molars typically have two roots but sometimes a supernumerary root presents distolingually called as radix entomolaris (RE. Aim: The present study evaluated the prevalence of permanent mandibular first molars featuring a distolingual root in Haryana (North India. Materials and Methods: Five hundred patients possessing bilateral mandibular first molars were selected for this study. The intraoral periapical radiographs were taken. The radiographs of these patients were evaluated under optimal conditions. A total of 1000 mandibular first molars were screened, and the incidence of three-rooted mandibular first molars, RE and the correlation between left and right side occurrence and between either gender were recorded. Statistical Analysis: The binary logistic regression test and Pearson's Chi-square test were used for statistical analysis. Results: The prevalence of three-rooted permanent mandibular first molars was 13% of the patients examined and 8.3% of the teeth examined. There was no statistically significant difference between gender and side of occurrence (P ≥ 0.05. The bilateral incidence of a symmetric distribution was 27.6 (18/65 among the RE teeth examined. Conclusion: RE is considered as an Asiatic trait. The occurrence of this macrostructure in the Haryana (North India population was found to be 13%. The clinician must thoroughly examine the radiographs before the initiation of endodontic therapy.

Root Canal Configuration of Mandibular First and Second Premolars in an Iranian Population

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Nemat Eskandarzadeh

2007-08-01

Full Text Available

Background and aims. It is critical to have a proper knowledge of the normal anatomy of the pulp and its variations for the success of endodontic treatment. The aim of this study was to determine the canal configuration and the prevalence of C-shaped canals in mandibular first and second premolars in a North-Western Iranian population.

Materials and methods. A total of 163 extracted mandibular first and 103 mandibular second premolars were injected with India ink and demineralized . They were made clear and transparent with methyl salicylate and the anatomy of their canal(s was studied.

Results. The results showed that 98% of mandibular first premolars had one root, 2% had two roots, 70.6% had one canal, 27.8% had two canals, 1.2% had three canals and the prevalence of C-shaped canals was 2.4%. All mandibular second premolars had one root, 80.5% had one canal, 17.5% had two canals and the prevalence of C-shaped canals was 2%.

Conclusion. It is important that clinicians, before treatment of mandibular first and second premolars, pay complete attention to radiographs, have a true concept of the number of root(s and canal(s, and prepare a correct access cavitiy.

Welfare assessment in pet rabbits

NARCIS (Netherlands)

Schepers, F.; Koene, P.; Beerda, B.

2009-01-01

One million pet rabbits are kept in The Netherlands, but there are no data available on their behaviour and welfare. This study seeks to assess the welfare of pet rabbits in Dutch households and is a first step in the development of a welfare assessment system. In an internet survey, housing

[Diagnosis and treatment of temporo-mandibular disorders in orthodontics].

Science.gov (United States)

Bocquet, Emmanuelle; Moreau, Alexis; Danguy, Michel; Danguy, Chantal

2010-03-01

Orthodontists are fully prepared to treat the problems of occlusion that they are called upon to deal with every day. On the other hand temporo-mandibular joint disorders present more obscure difficulties from the point of view of detection and diagnosis as well the management of their treatment. That is why a profound understanding of the anatomical and physiological functioning of the temporo-mandibular joint has become indispensable for today's orthodontists who are now asked to detect and diagnose an assortment of TMJ disturbances whose etiology may vary greatly. By performing a rigorous diagnostic procedure, based on a thorough clinical examination supported by careful axiographic and radiological studies, of temporo-mandibular malfunctioning and its underlying etiological causes, which are primarily dento-alveolar and occlusal in nature, orthodontists will be able to adopt an appropriate therapeutic approach that might be purely orthodontic or multi-disciplinary and carried out with the collaboration of specialists in occlusion, oral surgery, and even osteopathy. EDP Sciences, SFODF, 2010.

Recurrent osteochondroma of the mandibular condyle: A case report

International Nuclear Information System (INIS)

Kwon, Young Eun; Choi, Karp Shik; An, Chang Hyeon; Choi, So Young; An, Seo Young; Lee, Jae Seo

2017-01-01

A 21-year-old woman presented with facial asymmetry. Crepitus and clicking of the temporomandibular joint were noted. The midline deviated 5.5 mm to the left, and secondary malocclusion was observed. Panoramic and cone-beam computed tomographic images showed an irregular and exophytic bony mass on the anteromedial surface of the right mandibular condyle. A 3-phase bone scan revealed increased tracer uptake on the affected side. The lesion was treated with excision and reshaping under the diagnosis of osteochondroma confirmed by a histopathological examination. The lesion recurred after 3 years, and the patient underwent condylectomy. Mandibular condylar osteochondroma is often resected because it causes functional and aesthetic problems, but it rarely recurs. To the best of our knowledge, only 2 cases of recurrent osteochondromas of the mandibular condyle have been reported previously. Surgical treatment of the osteochondroma should be performed considering the possibility of recurrence, and long-term follow-up is recommended

Early Experience with Biodegradable Fixation of Pediatric Mandibular Fractures.

Science.gov (United States)

Mazeed, Ahmed Salah; Shoeib, Mohammed Abdel-Raheem; Saied, Samia Mohammed Ahmed; Elsherbiny, Ahmed

2015-09-01

This clinical study aims to evaluate the stability and efficiency of biodegradable self-reinforced poly-l/dl-lactide (SR-PLDLA) plates and screws for fixation of pediatric mandibular fractures. The study included 12 patients (3-12 years old) with 14 mandibular fractures. They were treated by open reduction and internal fixation by SR-PLDLA plates and screws. Maxillomandibular fixation was maintained for 1 week postoperatively. Clinical follow-up was performed at 1 week, 6 weeks, 3 months, and 12 months postoperatively. Radiographs were done at 1 week, 3 months, and 12 months postoperatively to observe any displacement and fracture healing. All fractures healed both clinically and radiologically. No serious complications were reported in the patients. Normal occlusion was achieved in all cases. Biodegradable osteofixation of mandibular fractures offers a valuable clinical solution for pediatric patients getting the benefit of avoiding secondary surgery to remove plates, decreasing the hospital stay, further painful procedures, and psychological impact.

3-D diagnosis-assisted management of anomalous mandibular molar

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Neelam Mittal

2012-01-01

Full Text Available This case report describes the successful non-surgical endodontic management of carious exposed three-rooted mandibular molar with four root canals detected on the pre-operative radiograph taken with 20 degrees mesial angulation and confirmed with a 64-slice helical computed tomography scan-assisted 3-D-reconstructed images. Access cavity shape was modified to locate the extra canal with respect to the distolingual root in the left mandibular first molar. Copious irrigation was accomplished with 5.25% sodium hypochlorite and 17% EDTA. Biomechanical preparation was done using protapers. Calcium hydroxide dressing was done for 1 week. The tooth was obturated using gutta percha and AH 26 root canal sealer, and it was permanently restored with composite. Clinical examination on follow-up visits revealed no sensitivity to percussion and palpation in the left mandibular first molar. Thorough knowledge of root canal variations and use of advanced diagnostic modalities lead to successful non-surgical management of the complex cases.

Recurrent osteochondroma of the mandibular condyle: A case report

Energy Technology Data Exchange (ETDEWEB)

Kwon, Young Eun; Choi, Karp Shik; An, Chang Hyeon; Choi, So Young; An, Seo Young [School of Dentistry, Kyungpook National University, Daegu (Korea, Republic of); Lee, Jae Seo [Dept. of Oral and Maxillofacial Radiology, School of Dentistry, Chonnam National University, Gwangju (Korea, Republic of)

2017-03-15

A 21-year-old woman presented with facial asymmetry. Crepitus and clicking of the temporomandibular joint were noted. The midline deviated 5.5 mm to the left, and secondary malocclusion was observed. Panoramic and cone-beam computed tomographic images showed an irregular and exophytic bony mass on the anteromedial surface of the right mandibular condyle. A 3-phase bone scan revealed increased tracer uptake on the affected side. The lesion was treated with excision and reshaping under the diagnosis of osteochondroma confirmed by a histopathological examination. The lesion recurred after 3 years, and the patient underwent condylectomy. Mandibular condylar osteochondroma is often resected because it causes functional and aesthetic problems, but it rarely recurs. To the best of our knowledge, only 2 cases of recurrent osteochondromas of the mandibular condyle have been reported previously. Surgical treatment of the osteochondroma should be performed considering the possibility of recurrence, and long-term follow-up is recommended.

Comparison of different radiographic methods for the detection of the mandibular canal

International Nuclear Information System (INIS)

Kim, Eun Kyung

2003-01-01

To compare the visibility of the mandibular canal at the different radiographic methods such as conventional panoramic radiographs, Vimplant multiplanar reformatting (MPR)-CT panoramic images, Vimplant MPR-CT paraxial images and film-based DentaScan MPR-CT images. Data of 11 mandibular dental implant patients, who had been planned treatment utilizing both panoramic and MPR-CT examination with DentaScan software (GE Medical systems, Milwaukee, USA), were used in this study. The archived axial CT data stored on CD-R discs were transferred to a personal computer with 17' LCD monitor. Paraxial and panoramic images were reconstructed using Vimplant software (CyberMed Inc., Seoul, Korea). Conventional panoramic radiographs, monitor-based Vimplant MPR-CT panoramic images, monitor-based Vimplant MPR-CT paraxial images, and film-based DentaScan MPR-CT images were evaluated for visibility of the mandibular canal at the mental foramen, 1 cm, 2 cm, and 3 cm posterior to mental foramen using the 4-point grading score. Vimplant MPR-CT panoramic, paraxial, and DentaScan MPR-CT images revealed significantly clearer images than conventional panoramic radiographs. Particularly at the region 1 cm posterior to mental foramen, conventional panoramic radiographs showed a markedly lower percentage of 'excellent' mandibular canal images than images produced by other modalities. Vimplant MPR-CT and DentaScan MPR-CT images did not show significant difference in visibility of the mandibular canal. The study results shoe that Vimplant and DentaScan MPR-CT imaging systems offer significantly better images of the mandibular canal than conventional panoramic radiograph.

Endodontic therapy for a fused mandibular molar.

Science.gov (United States)

Rotstein, I; Moshonov, J; Cohenca, N

1997-06-01

Variations in tooth morphology present a clinical challenge when endodontic treatment is required. A case of conservative endodontic therapy for a fused mandibular second and third molar is presented.

Neurovascular Content of the Mandibular Canal and Its Clinical Relevance: A Literature Review of the Related Anatomical and Radiological Studies

Directory of Open Access Journals (Sweden)

Eliades Apostolos N.

2014-11-01

Full Text Available In literature, anatomical variations of the inferior alveolar nerve branches (infratemporal, extraosseous and intraosseous are reported and their importance in clinical practice is discussed too. The spatial vessels’ position in relationship with the nerve in the mandibular canal was explored, which is of clinical significance in impacted third molar and implant surgery. It is believed that the neurovascular content of the main mandibular canal follows any variations of the mandibular canal i.e. bifid mandibular, retromolar and accessory mental canals. Retrospective studies and case reports reported the presence of multiple foramina on the medial surface of the ramus, near the main mandibular foramen. In some cases, one supplementary mandibular foramen was found to be connected with the lower third molar, which is called “temporal crest canal”. Others found an accessory mandibular foramen that led into a second mandibular canal which joined the main mandibular canal (double anteriorly. The bony canals contained a terminal branch of the anterior trunk of the mandibular nerve or a branch of inferior alveolar nerve before it entered the mandibular foramen.

Use of monocortical miniplates for the intraoral treatment of mandibular fractures.

Science.gov (United States)

Chiodo, Thomas A; Milles, Maano

2009-03-01

Fixation of mandibular fractures using rigid hardware has gained wide acceptance over the past 3 decades. The goal of rigid internal fixation is to allow for fracture healing with limited, or no, time in maxillo-mandibular fixation. There has been significant evolution in plate and screw materials and design over the past 30 years. The term miniplate is used to describe a fracture plate with a screw diameter of 2.0 mm or less. With correct diagnosis and understanding of the forces affecting mandible fractures, miniplates can be applied transorally in various situations, allowing for less invasive treatment with open reduction of mandible fractures. This article describes the use of monocortical miniplates for the intraoral treatment of mandibular fractures.

Market Driving to Develop Rabbit Meat Products in Indonesia

OpenAIRE

Atien Priyanti; Yono Cahyo Rahadjo

2012-01-01

Rabbit meat is a nutritional food containing high protein and low cholesterol, fat and sodium. Current research in rabbit production is aimed for developing production strategies to increase the nutritional and economic values of rabbit meat products as functional food. Nowadays, producing rabbit is a popular farming activity in many parts of Indonesia as a small and medium scale operation for food security and cash income. Rabbit farming is to produce meat, skin and hides, fur, organic ferti...

Relationship of maxillary 3-dimensional posterior occlusal plane to mandibular spatial position and morphology.

Science.gov (United States)

Coro, Jorge C; Velasquez, Roberto L; Coro, Ivette M; Wheeler, Timothy T; McGorray, Susan P; Sato, Sadao

2016-07-01

The purpose of this study was to examine the relationship of the 3-dimensional (3D) posterior occlusal plane (POP) and the mandibular 3D spatial position. The relationship of the POP to mandibular morphology was also investigated. Retrospective data from a convenience sample of pretreatment diagnostic cone-beam computed tomography scans were rendered using InVivo software (Anatomage, San Jose, Calif). The sample consisted of 111 subjects (51 male, 60 female) and included growing and nongrowing subjects of different races and ethnicities. The 3D maxillary POP was defined by selecting the cusp tips of the second premolars and the second molars on the rendered images of the subjects. The angles made by this plane, in reference to the Frankfort horizontal plane, were measured against variables that described the mandibular position in the coronal, sagittal, and axial views. The POP was also compared with bilateral variables that described mandibular morphology. There were significant differences of the POP among the different skeletal malocclusions (P <0.0001). The POP showed significant correlations with mandibular position in the sagittal (P <0.0001), coronal (P <0.05), and axial (P <0.05) planes. The POP also showed a significant correlation with mandibular morphology (P <0.0001). These findings suggest that there is a distinct and significant relationship between the 3D POP and the mandibular spatial position and its morphology. Copyright © 2016 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

Effect of bradykinin antagonists on bradykinin-induced plasma extravasation, venoconstriction, prostaglandin E2 release, nociceptor stimulation and contraction of the iris sphincter muscle in the rabbit.

Science.gov (United States)

Griesbacher, T.; Lembeck, F.

1987-01-01

1 The inhibition of the bradykinin-induced plasma extravasation by six bradykinin (Bk) antagonists was tested on rabbit skin. All of them showed inhibitory effects without an agonistic action in the does used. B4310 (Lys-Lys-3-Hyp-5,8-Thi-7-DPhe-Bk) was the most active antagonist and was therefore used in the subsequent experiments. 2 B4310 (5-500 nM) antagonized the bradykinin-induced reduction of the venous outflow from the rabbit isolated ear in dose-dependent manner without affecting the arterial vasoconstriction induced by angiotensin II. 3 The bradykinin-induced release of prostaglandin E2 (PGE2) from the perfused rabbit ear was reduced by 63% when B4310 (800 nM) was infused before, during and after the bradykinin injection. 4 Bradykinin was injected into the ear artery of anaesthetized rabbits and the reflex hypotensive response was used as indicator of the nociception. The response was antagonized by a local infusion of B4310 (50 and 500 nM). The antagonism was dose-dependent and reversible. The parallel shift of the dose-response curve to bradykinin suggests a competitive inhibition. However, B4310 did not antagonize acetylcholine-induced nociceptor stimulation. 5 B4310 inhibited bradykinin-induced stimulation of the trigeminal nerve which results in a substance P-mediated contraction of the iris sphincter muscle. A pA2 of 7.59 was calculated. B4310 did not inhibit capsaicin-induced contractions. 6 It is concluded that B4310 inhibits specifically five different actions of bradykinin which are related to its possible pathophysiological role. PMID:3479223

Insulin degradation products from perfused rat kidney

International Nuclear Information System (INIS)

Duckworth, W.C.; Hamel, F.G.; Liepnieks, J.; Peavy, D.; Frank, B.; Rabkin, R.

1989-01-01

The kidney is a major site for insulin metabolism, but the enzymes involved and the products generated have not been established. To examine the products, we have perfused rat kidneys with insulin specifically iodinated on either the A14 or the B26 tyrosine. Labeled material from both the perfusate and kidney extract was examined by Sephadex G50 and high-performance liquid chromatography (HPLC). In perfusate from a filtering kidney, 22% of the insulin-sized material was not intact insulin on HPLC. With the nonfiltering kidney, 10.6% was not intact insulin. Labeled material from HPLC was sulfitolyzed and reinjected on HPLC. By use of 125 I-iodo(A14)-insulin, almost all the degradation products contained an intact A-chain. By use of 125 I-iodo(B26)-insulin, several different B-chain-cleaved products were obtained. The material extracted from the perfused kidney was different from perfusate products but similar to intracellular products from hepatocytes, suggesting that cellular metabolism by kidney and liver are similar. The major intracellular product had characteristics consistent with a cleavage between the B16 and B17 amino acids. This product and several of the perfusate products are also produced by insulin protease suggesting that this enzyme is involved in the degradation of insulin by kidney

Effects of luminal flow and nucleotides on [Ca(2+)](i) in rabbit cortical collecting duct.

Science.gov (United States)

Woda, Craig B; Leite, Maurilo; Rohatgi, Rajeev; Satlin, Lisa M

2002-09-01

Nucleotide binding to purinergic P2 receptors contributes to the regulation of a variety of physiological functions in renal epithelial cells. Whereas P2 receptors have been functionally identified at the basolateral membrane of the cortical collecting duct (CCD), a final regulatory site of urinary Na(+), K(+), and acid-base excretion, controversy exists as to whether apical purinoceptors exist in this segment. Nor has the distribution of receptor subtypes present on the unique cell populations that constitute Ca(2+) the CCD been established. To examine this, we measured nucleotide-induced changes in intracellular Ca(2+) concentration ([Ca(2+)](i)) in fura 2-loaded rabbit CCDs microperfused in vitro. Resting [Ca(2+)](i) did not differ between principal and intercalated cells, averaging approximately 120 nM. An acute increase in tubular fluid flow rate, associated with a 20% increase in tubular diameter, led to increases in [Ca(2+)](i) in both cell types. Luminal perfusion of 100 microM UTP or ATP-gamma-S, in the absence of change in flow rate, caused a rapid and transient approximately fourfold increase in [Ca(2+)](i) in both cell types (P < 0.05). Luminal suramin, a nonspecific P2 receptor antagonist, blocked the nucleotide- but not flow-induced [Ca(2+)](i) transients. Luminal perfusion with a P2X (alpha,beta-methylene-ATP), P2X(7) (benzoyl-benzoyl-ATP), P2Y(1) (2-methylthio-ATP), or P2Y(4)/P2Y(6) (UDP) receptor agonist had no effect on [Ca(2+)](i). The nucleotide-induced [Ca(2+)](i) transients were inhibited by the inositol-1,4,5-triphosphate receptor blocker 2-aminoethoxydiphenyl borate, thapsigargin, which depletes internal Ca(2+) stores, luminal perfusion with a Ca(2+)-free perfusate, or the L-type Ca(2+) channel blocker nifedipine. These results suggest that luminal nucleotides activate apical P2Y(2) receptors in the CCD via pathways that require both internal Ca(2+) mobilization and extracellular Ca(2+) entry. The flow-induced rise in [Ca(2+)](i) is

Pulmonary artery perfusion versus no perfusion during cardiopulmonary bypass for open heart surgery in adults

DEFF Research Database (Denmark)

Buggeskov, Katrine B; Grønlykke, Lars; Risom, Emilie C

2018-01-01

BACKGROUND: Available evidence has been inconclusive on whether pulmonary artery perfusion during cardiopulmonary bypass (CPB) is associated with decreased or increased mortality, pulmonary events, and serious adverse events (SAEs) after open heart surgery. To our knowledge, no previous systematic...... handsearched retrieved study reports and scanned citations of included studies and relevant reviews to ensure that no relevant trials were missed. We searched for ongoing trials and unpublished trials in the World Health Organization International Clinical Trials Registry Platform (ICTRP) and at clinicaltrials......). We used GRADE principles to assess the quality of evidence. MAIN RESULTS: We included in this review four RCTs (210 participants) reporting relevant outcomes. Investigators randomly assigned participants to pulmonary artery perfusion with blood versus no perfusion during CPB. Only one trial included...

Confirmation and phylogenetic analysis of rabbit hemorrhagic disease virus in free-living rabbits from the Netherlands

NARCIS (Netherlands)

van de Bildt, M. W. G.; van Bolhuis, G. H.; van Zijderveld, F.; van Riel, D.; Drees, J. M.; Osterhaus, A. D. M. E.; Kuiken, T.

2006-01-01

The number of free-living European rabbits (Oryctolagus cuniculus) in the Netherlands has declined dramatically in recent years. Although rabbit hemorrhagic disease virus (RHDV) infection has been implicated as a possible cause of this decline, the definitive diagnosis has not been reported. We

Application of the Mandible Injury Severity Score to Pediatric Mandibular Fractures.

Science.gov (United States)

Swanson, Edward W; Susarla, Srinivas M; Ghasemzadeh, Ali; Mundinger, Gerhard S; Redett, Richard J; Tufaro, Anthony P; Manson, Paul N; Dorafshar, Amir H

2015-07-01

The Mandible Injury Severity Score (MISS) has been used to evaluate adult mandibular fractures. The purpose of this study was to evaluate the MISS in a cohort of pediatric patients. This was a retrospective study of pediatric patients treated for mandibular fractures over a 20-year period. Patients were included if they had computed tomographic imaging available for review and had at least 1 post-treatment visit. The primary predictor variable was the MISS. Secondary predictors were demographic and injury-associated factors. The outcome was treatment-associated complications. Descriptive, bivariate, and multiple logistic regression statistics were computed. One hundred sixteen patients with mandibular fractures were identified; 73 (62.9%) met the inclusion criteria. The sample's mean age was 8.5 ± 4.1 years; 44% were girls. Motor vehicle collisions (60%) and falls (15.1%) were the most common mechanisms. More than 50% of patients had an extra-mandibular injury. The mean MISS was 13.5 ± 7.8. Forty-five percent of the sample underwent open reduction and internal fixation. Complications were noted in 20.5% of patients, of which malocclusion was the most common (8.2%). Increasing MISS was associated with complications (P pediatric patients with mandibular fractures, increased severity of injury is associated with complications, even after controlling for the effects of multiple confounders, including open treatment. Copyright © 2015 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

TMJ response to mandibular advancement surgery: an overview of risk factors

Science.gov (United States)

VALLADARES-NETO, José; CEVIDANES, Lucia Helena; ROCHA, Wesley Cabral; ALMEIDA, Guilherme de Araújo; de PAIVA, João Batista; RINO-NETO, José

2014-01-01

Objective In order to understand the conflicting information on temporomandibular joint (TMJ) pathophysiologic responses after mandibular advancement surgery, an overview of the literature was proposed with a focus on certain risk factors. Methods A literature search was carried out in the Cochrane, PubMed, Scopus and Web of Science databases in the period from January 1980 through March 2013. Various combinations of keywords related to TMJ changes [disc displacement, arthralgia, condylar resorption (CR)] and aspects of surgical intervention (fixation technique, amount of advancement) were used. A hand search of these papers was also carried out to identify additional articles. Results A total of 148 articles were considered for this overview and, although methodological troubles were common, this review identified relevant findings which the practitioner can take into consideration during treatment planning: 1- Surgery was unable to influence TMJ with preexisting displaced disc and crepitus; 2- Clicking and arthralgia were not predictable after surgery, although there was greater likelihood of improvement rather than deterioration; 3- The amount of mandibular advancement and counterclockwise rotation, and the rigidity of the fixation technique seemed to influence TMJ position and health; 4- The risk of CR increased, especially in identified high-risk cases. Conclusions Young adult females with mandibular retrognathism and increased mandibular plane angle are susceptible to painful TMJ, and are subject to less improvement after surgery and prone to CR. Furthermore, thorough evidenced-based studies are required to understand the response of the TMJ after mandibular advancement surgery. PMID:24626243

A Simplified Way for the Stabilization of Pediatric Mandibular Fracture With an Occlusal Splint.

Science.gov (United States)

Demirkol, Mehmet; Demirkol, Nermin; Abdo, Omar Hasan; Aras, Mutan Hamdi

2016-06-01

The management of pediatric mandibular fractures is challenging for maxillofacial surgeons due to ongoing mandibular growth involving tooth buds. The treatment of such fractures has been a topic of much research. Generally accepted methods for the treatment of mandibular parasymphyseal or symphyseal fractures in children are conservative approaches involving the use of acrylic splints, lateral compression with an open-cap splint stabilized by circummandibular wiring, and maxillomandibular fixation with an arch bar and eyelet wiring. The aim of this technical note was to describe a straightforward approach to the treatment of pediatric mandibular fractures, in which an occlusal splint is secured to prevent trauma to the soft tissue, without the need for general anesthesia.

Active Shape Analysis of Mandibular Growth

DEFF Research Database (Denmark)

Hilger, Klaus Baggesen; Larsen, Rasmus; Kreiborg, Sven

2003-01-01

This work contains a clinical validation using biological landmarks of a Geometry Constrained Diffusion registration of mandibular surfaces. Canonical Correlations Analysis is extended to analyse 3D landmarks and the correlations are used as similarity measures for landmark clustering. A novel Ac...

Ultrastructure of Reissner's membrane in the rabbit

DEFF Research Database (Denmark)

Qvortrup, K.; Rostgaard, Jørgen; Bretlau, P.

1994-01-01

Anatomy, Reissner's membrane, electron microscopy, tubulocisternal endoplasmic reticulum, subsurface cisterns, rabbit......Anatomy, Reissner's membrane, electron microscopy, tubulocisternal endoplasmic reticulum, subsurface cisterns, rabbit...

Aesthethic and masticatory rehabilitation on post mandibular resection with combination of hollow obturator and hybrid prosthesis

Directory of Open Access Journals (Sweden)

Arif Rachman

2009-06-01

Full Text Available Background: Replacing tooth lost caused by caries, periodontal disease, trauma and neoplasm including ameloblastoma which requires mandibular resection is important. Purpose: The aim of the study to rehabilitation of post mandibular resection with combination of hollow obturator and hybrid prosthesis. Case: A patient 25 years old, male, for having prosthesis to cover defect due to post right mandibular resection. Case Management: In this presented case, mandibular plate was applied due to spreading defect with losing almost a half body of mandible (class II modification 2 according to cantor and curtis classification. The design of therapy was mandibular obturator using hybrid prosthesis (removable partial denture metal frame and fixed splint crown with precision attachment with hollow obturator. The application was based on several advantages: good aesthetic performance, retention, stability, lighter weight and equal share of vertical load for teeth on non surgical site. The result of control I, II, III, showed that aesthetic performance, masticatory function, speech and swallowing were in good condition. Conclusion: The design of mandibular obturator using hybrid denture with hollow obturator could rehabilitate aesthetic performance, masticatory function, speech and swallowing for patient with post mandibular resection.

[The temporo-mandibular articulation].

Science.gov (United States)

Dargaud, J; Vinkka-Puhakka, H

2004-04-01

The standing posture of humans has created both morphological and functional adaptations in the temporo-mandibular joint and the masticatory function. This biped state is the one of the most important characteristic of human evolution. It is furthermore the agent determining most of the functional changes in the whole body. This survey will be carried out in several levels including, a descriptive anatomy, biomechanics, radiological imaging, functioning in the articulation of TMJ. The descriptive anatomic picture will be obtained by the traditional dissection techniques. 20 TMJ joints are dissected from 10 cadavers: 7 cadavers, 65-75 year old, 3 cadavers, 60-65 year old. The x-rays are lateral view and the subjects of the radiological imaging are young's, adults and olds: 1, 3 y-old Male; 1, 7 y-old Female; 1, 14 y-old Female; 10, 19-23 y-old Male; 1, 26 y-old Female; 1, 34 y-old Male; 1, 75 y-old Female. The anatomic elements in the TMJ well resembled the ones described in the literature of the capsule, the ligament, the masticator muscles (masseter, temporal, medial and lateral pterygoids). The temporo-mandibular ligament proved to be difficult to separate from the capsule in some of the specimens. Sometimes it was not always found after a dissection.

Value of chest X-ray combined with perfusion scan versus ventilation/perfusion scan in acute pulmonary embolism

NARCIS (Netherlands)

de Groot, M. R.; Turkstra, F.; van Marwijk Kooy, M.; Oostdijk, A. H.; van Beek, E. J.; Büller, H. R.

2000-01-01

The main purpose of ventilation scanning, as adjunct to perfusion lung scintigraphy, in acute pulmonary embolism is to allow for the classification of segmental perfusion defects as mismatched, which is generally accepted as proof for the presence of pulmonary embolism. We examined whether this

Myocardial perfusion scintigraphy - possibilities of diagnosing CAD

International Nuclear Information System (INIS)

Tsonevska, A.

1998-01-01

A reviewing the diagnostic methods used in the intricate process of evaluating CAD patients in a attempt to establish the role played by radionuclide methods in the diagnostic strategy is done. The perfusion cardiotropic radiopharmaceuticals used and the various methods of evaluating myocardial are discussed. Although 210 Tl-chloride is the most widely used myocardial perfusion agent, recently 99m Tc-MIBI is proposed as an alternative because of its advantages. Myocardial perfusion assessment is done by various techniques depending on the specific aim, each of them having its proper advantages and shortcomings. The inference is reached that regardless of the routine practical implementation of myocardial perfusion scintigraphy and comprehensive studies along this line in course, there are problems still not well enough clarified awaiting solution

Posttraumatic Mandibular Asymmetry Presenting in a Young Adult

Directory of Open Access Journals (Sweden)

Mahnaz Sheikhi, DDS,MS

2017-03-01

Full Text Available One of the most common sites of injury of the facial skeleton is mandibular condyle. However, it is the least diagnosed site of trauma in the head and neck regions. A trauma to the mandible and specifically condylar zone during childhood, may lead to asymmetry or mandibular bilateral distortion, which is usually manifested in the second decade of life when the etiology is unknown to most people. This report is about an adult male complaining about facial asymmetry with an unknown source. Obvious clicking at the right side and shorter right ramus and condyle's head deviation directed us to a childhood trauma and fracture.

Management of pediatric mandibular fracture: a case series.

Science.gov (United States)

Agarwal, Ravi M; Yeluri, Ramakrishna; Singh, Chanchal; Chaudhry, Kalpna; Munshi, Autar K

2014-09-01

A pediatric mandibular fracture can cause a child severe pain and the parent or caregiver extreme worry. While the pattern of fractures and associated injuries in children is similar to adults, the incidence is low. Due to a number of factors, including the anatomical complexity of the developing mandible in a child, management of such fractures differs from that of adults and can greatly challenge the pediatric dentist. Various treatment modalities of managing mandibular fracture are available, such as closed/open cap splint with circummandibular wiring, arch-bar fixation, and cementation of the cap splint. This article reviews 19 cases in the management of pediatric facial fracture using varied treatment methods.

Goal-directed-perfusion in neonatal aortic arch surgery.

Science.gov (United States)

Cesnjevar, Robert Anton; Purbojo, Ariawan; Muench, Frank; Juengert, Joerg; Rueffer, André

2016-07-01

Reduction of mortality and morbidity in congenital cardiac surgery has always been and remains a major target for the complete team involved. As operative techniques are more and more standardized and refined, surgical risk and associated complication rates have constantly been reduced to an acceptable level but are both still present. Aortic arch surgery in neonates seems to be of particular interest, because perfusion techniques differ widely among institutions and an ideal form of a so called "total body perfusion (TBP)" is somewhat difficult to achieve. Thus concepts of deep hypothermic circulatory arrest (DHCA), regional cerebral perfusion (RCP/with cardioplegic cardiac arrest or on the perfused beating heart) and TBP exist in parallel and all carry an individual risk for organ damage related to perfusion management, chosen core temperature and time on bypass. Patient safety relies more and more on adequate end organ perfusion on cardiopulmonary bypass, especially sensitive organs like the brain, heart, kidney, liver and the gut, whereby on adequate tissue protection, temperature management and oxygen delivery should be visualized and monitored.

Mandibular molar crown-topography, a biological predisposing ...

African Journals Online (AJOL)

Mandibular molar crown-topography, a biological predisposing factor to development of caries – a post-mortem analysis of 2500 extracted lower permanent molars at the dental centre, University of Benin teaching hospital.

Coronectomy of the mandibular third molar: Respect for the inferior alveolar nerve

NARCIS (Netherlands)

Kouwenberg, A. J.; Stroy, L. P. P.; Rijt, E. D. Vree-V. D.; Mensink, G.; Gooris, P. J. J.

2016-01-01

The aim of this study was to evaluate the outcomes of coronectomy as an alternative surgical procedure to complete removal of the impacted mandibular third molar in patients with a suspected close relationship between the tooth root(s) and the mandibular canal. A total of 151 patients underwent

Cephalometric evaluation of surgical mandibular advancement

Directory of Open Access Journals (Sweden)

Eloísa Marcantônio Boeck

2010-06-01

Full Text Available The treatment of Class II adult individuals with mandibular deficiency has been the combination of orthodontic treatment and orthognathic surgery. Therefore, a study was conducted in which cephalometric analysis was used to evaluate the influence of dentoalveolar decompensation in Class II patients submitted to orthodontic and surgical treatment for mandibular advancement, by bilateral osteotomy of the mandibular ramus. A sample of 15 leukoderma adult female patients were selected and three cephalometric radiographs of each patient, taken before the orthodontic treatment, before surgery and after at least 6 months postoperatively, were analyzed in a total of 45 roentgenograms. The tracings were made by the manual method and the points were digitalized using software. The results showed that values of SNB increased from 75.6 to 78.6°. The measures BNP and PGNP were reduced from -12.7 to -7.7 mm and -12.7 to -6.6 mm, respectively. For ANB there was a reduction of 3.23° (from 8.1° to 4.9°. Likewise, the values of AOBO were diminished by 6.3 mm (from 7.6 to 1.3 mm, and in the values of OJ there was a reduction of 5.7 mm (from 9 to 3.3 mm. It was concluded that the pre-surgical orthodontic treatment promoted minimal and variable dental and skeletal changes in the final result. The surgical treatment caused significant skeletal changes, especially in the measurements related to the mandible (SNB, BNP, PGNP and SNPM or indirectly to it (ANB, AOBO and OJ.

Cephalometric evaluation of surgical mandibular advancement.

Science.gov (United States)

Boeck, Eloísa Marcantônio; Kuramae, Mayury; Lunardi, Nádia; Santos-Pinto, Ary dos; Mazzonetto, Renato

2010-01-01

The treatment of Class II adult individuals with mandibular deficiency has been the combination of orthodontic treatment and orthognathic surgery. Therefore, a study was conducted in which cephalometric analysis was used to evaluate the influence of dentoalveolar decompensation in Class II patients submitted to orthodontic and surgical treatment for mandibular advancement, by bilateral osteotomy of the mandibular ramus. A sample of 15 leukoderma adult female patients were selected and three cephalometric radiographs of each patient, taken before the orthodontic treatment, before surgery and after at least 6 months postoperatively, were analyzed in a total of 45 roentgenograms. The tracings were made by the manual method and the points were digitalized using software. The results showed that values of SNB increased from 75.6 to 78.6 degrees. The measures BNP and PGNP were reduced from -12.7 to -7.7 mm and -12.7 to -6.6 mm, respectively. For ANB there was a reduction of 3.23 degrees (from 8.1 degrees to 4.9 degrees). Likewise, the values of AOBO were diminished by 6.3 mm (from 7.6 to 1.3 mm), and in the values of OJ there was a reduction of 5.7 mm (from 9 to 3.3 mm). It was concluded that the pre-surgical orthodontic treatment promoted minimal and variable dental and skeletal changes in the final result. The surgical treatment caused significant skeletal changes, especially in the measurements related to the mandible (SNB, BNP, PGNP and SNPM) or indirectly to it (ANB, AOBO and OJ).

Impairment of myocardial perfusion in children with sickle cell disease; Alteration de la perfusion myocardique chez l'enfant drepanocytaire

Energy Technology Data Exchange (ETDEWEB)

Maunoury, C. [Hopital Necker-Enfants-Malades, Service de Medecine Nucleaire, 75 - Paris (France); Acar, P. [Centre Hospitalier Universitaire, Hopital des Enfants, Service de Cardiologie Pediatrique, 31 - Toulouse (France); Montalembert, M. de [Hopital Necker-Enfants-Malades, Service de Pediatrie Generale, 75 - Paris (France)

2003-10-01

While brain, bone and spleen strokes are well documented in children with sickle cell disease (SCD), impairment of myocardial perfusion is an unknown complication. Non invasive techniques such as exercise testing and echocardiography have a low sensitivity to detect myocardial ischemia in patients with SCD. We have prospectively assessed myocardial perfusion with Tl-201 SPECT in 23 patients with SCD (10 female, 13 male, mean age 12 {+-} 5 years). Myocardial SPECT was performed after stress and 3 hours later after reinjection on a single head gamma camera equipped with a LEAP collimator (64 x 64 matrix size format, 30 projections over 180 deg C, 30 seconds per step). Left ventricular ejection fraction (LVEF) was assessed by equilibrium radionuclide angiography at rest on the same day. Myocardial perfusion was impaired in 14/23 patients: 9 reversible defects and 5 fixed defects. The left ventricular cavity was dilated in 14/23 patients. The mean LVEF was 63 {+-} 9%. There was no relationship between myocardial perfusion and left ventricular dilation or function. The frequent impairment of myocardial perfusion in children with SCD could lead to suggest a treatment with hydroxyurea, an improvement of perfusion can be noted with hydroxyurea. (author)

Mandibular Kondil Kırıkları ve Tedavi Yöntemleri

OpenAIRE

Kısa, Halil İbrahim; Tatlı, Ufuk; Kürkcü, Mehmet

2014-01-01

Maxillofacial injuries are most commonly associated with falls, motor and vehicle accidents, sports-related trauma, and interpersonel violence. The complexity of mandibular condyle region and its anatomic proximity to other craniofacial structures complicate diagnosis and treatment. Thus, treatment approaches of mandibular condyle fracture are still controversial. In the literature, different success rates are reported about observation versus treatment, closed reduction versus open reduction...

Computerized tomography of the mandibular joints and masticatory muscles

International Nuclear Information System (INIS)

Huels, A.B.

1981-01-01

A methodology for computerized tomography of the mandibular joints was developed and applied in 80 test persons. Imaging of the mandibular joints is possible with a tomographic technique with 5 mm-overlap, full utilisation of the enlargement capacity of the imaging device, and combined use of transversal and coronary tomography. The method yields full latero-medial, cranio-caudal and anterior-posterior views of the condyle and fossa contours, free of interferences and of distortions caused by the projection. Positional diagnoses are thus possible as well as diagnoses of pathological structural changes. (orig./MG) [de

Use of rectangular grid miniplates for fracture fixation at the mandibular angle.

Science.gov (United States)

Hochuli-Vieira, Eduardo; Ha, Thi Khanh Linh; Pereira-Filho, Valfrido Antonio; Landes, Constantin Alexander

2011-05-01

The aim of this study was to evaluate the clinical outcome of patients with mandibular angle fractures treated by intraoral access and a rectangular grid miniplate with 4 holes and stabilized with monocortical screws. This study included 45 patients with mandibular angle fractures from the Department of Oral and Maxillofacial Surgery São Paulo State University, Araraquara, Brazil, and from the Clinic of Oral and Maxillofacial Surgery at the University of Frankfurt, Germany. The 45 fractures of the mandibular angle were treated with a rectangular grid miniplate of a 2.0-mm system by an intraoral approach with monocortical screws. Clinical evaluations were postoperatively performed at 15 and 30 days and 3 and 6 months, and the complications encountered were recorded and treated. The infection rate was 4.44% (2 patients), and in 1 patient it was necessary to replace hardware. This patient also had a fracture of the left mandibular body; 3 patients (6.66%) had minor occlusal changes that have been resolved with small occlusal adjustments. Before surgery, 15 patients (33.33%) presented with hypoesthesia of the inferior alveolar nerve; 4 (8.88%) had this change until the last clinical control, at 6 months. The rectangular grid miniplate used in this study was stable for the treatment of simple mandibular angle fractures through intraoral access, with low complication rates, easy handling, and easy adjustment, with a low cost. Concomitant mandibular fracture may increase the rate of complications. This plate should be indicated in fractures with sufficient interfragmentary contact. Copyright © 2011 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

Surgical treatment of sagittal fracture of mandibular condyle using long-screw osteosynthesis.

Science.gov (United States)

Luo, Shufang; Li, Bo; Long, Xing; Deng, Mohong; Cai, Hengxing; Cheng, Yong

2011-07-01

The retrospective study evaluated long-screw (bicortical screw) osteosynthesis used in the surgical treatment of sagittal fracture of the mandibular condyle and compared it with titanium plates and removal of the condylar fragment. Ninety-five patients with sagittal fracture of the mandibular condyle received open surgical treatment from 1997 to 2008. Among these patients, the condylar fragments were fixed with long screws in 56 cases (group A), were fixed with titanium plates in 12 cases (group B), and were completely removed in 24 cases (group C). Follow-up was carried out clinically and radiologically. The clinical features included limitation of mandibular mobility, occlusion disturbance, lateral deviation on mouth opening, joint pain, clicking, facial asymmetry, and patient's subjective evaluation. The radiologic parameters consisted of degree of bony resorption, bony change, change of osteosynthesis material, and shortening of mandibular ramus height. Anatomic reduction and functional restoration were obtained and no severe complication was detected in group A. However, 3 of 14 patients had severe osteoarthrosis and 2 of 14 patients had ankylosis in group B. In group C 3 of 24 patients had mandibular retrusion, 4 of 24 patients had front teeth open bite, 4 of 24 patients had severe osteoarthrosis, and 1 of 24 patients had ankylosis. The long-screw fixation group had a more favorable prognosis than the titanium plate group and the group in which removal of the condylar fragment was performed. The long-screw fixation technique might be suitable for use in the surgical treatment of sagittal fractures of the mandibular condyle. Copyright © 2011 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

Occlusion and Temporomandibular Function among Subjects with Mandibular Distal Extension Removable Partial Dentures.

NARCIS (Netherlands)

Creugers, N.H.J.; Witter, D.J.; Spijker, A. van 't; Gerritsen, A.E.; Kreulen, C.M.

2010-01-01

Objective. To quantify effects on occlusion and temporomandibular function of mandibular distal extension removable partial dentures in shortened dental arches. Methods. Subjects wearing mandibular extension removable partial dentures (n = 25) were compared with subjects with shortened dental arches

Occurrence of Gastrointestinal Helminths in rabbits with special ...

African Journals Online (AJOL)

2013-09-25

Sep 25, 2013 ... droppings to digest their food further and extract sufficient nutrients (Oaktreevet, 2010). Rabbits are generally infected with numerous parasites. Parasitic infections have caused considerable losses to rabbits in the region. Numbers of parasites are responsible for illness of rabbits (Allan et al., 1999).

Strategic camouflage treatment of skeletal Class III malocclusion (mandibular prognathism) using bone-borne rapid maxillary expansion and mandibular anterior subapical osteotomy.

Science.gov (United States)

Seo, Yu-Jin; Lin, Lu; Kim, Seong-Hun; Chung, Kyu-Rhim; Nelson, Gerald

2016-01-01

This case report presents the camouflage treatment that successfully improved the facial profile of a patient with a skeletal Class III malocclusion using bone-borne rapid maxillary expansion and mandibular anterior subapical osteotomy. The patient was an 18-year-old woman with chief complaints of crooked teeth and a protruded jaw. Camouflage treatment was chosen because she rejected orthognathic surgery under general anesthesia. A hybrid type of bone-borne rapid maxillary expander with palatal mini-implants was used to correct the transverse discrepancy, and a mandibular anterior subapical osteotomy was conducted to achieve proper overjet with normal incisal inclination and to improve her lip and chin profile. As a result, a Class I occlusion with a favorable inclination of the anterior teeth and a good esthetic profile was achieved with no adverse effects. Therefore, the hybrid type of bone-borne rapid maxillary expander and a mandibular anterior subapical osteotomy can be considered effective camouflage treatment of a skeletal Class III malocclusion, providing improved inclination of the dentition and lip profile. Copyright © 2016 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

Market Driving to Develop Rabbit Meat Products in Indonesia

Directory of Open Access Journals (Sweden)

Atien Priyanti

2012-09-01

Full Text Available Rabbit meat is a nutritional food containing high protein and low cholesterol, fat and sodium. Current research in rabbit production is aimed for developing production strategies to increase the nutritional and economic values of rabbit meat products as functional food. Nowadays, producing rabbit is a popular farming activity in many parts of Indonesia as a small and medium scale operation for food security and cash income. Rabbit farming is to produce meat, skin and hides, fur, organic fertilizers and pet or fancy animals. Consumption of rabbit meat is considered very low, due partly to low meat supply and inavailability of marketing. In some tourist areas, such as Lembang (West Java, Tawangmangu (Central Java, Sarangan and Batu (East Java rabbit meat is a specific food. Attempt to create and drive rabbit markets will simultaneously increase meat production to fulfill the demand and meet economic scale of farming. Hence, this will give significant impact to the farmers’ welfare. Availability of good quality meat, dissemination and diversification of meat products, production efficiency toward competitive price along with its proper marketing strategy will drive consumers’ preferences to consume more rabbit meat. Market driving needs to be created in order to promote rabbit meat products by establishing food outlets. This program has been developed by a farmers group in Magelang, Central Java. During the period of 2006 – 2007 the food outlets had increased to 5 outlets, and in 2012 become 9 outlets. This market driving will also have an impact on changing orientation of rabbit farming from traditional to a small and medium economic scale that will influence the production efficiency.

Effect of x-ray tube current on the accuracy of cerebral perfusion parameters obtained by CT perfusion studies

International Nuclear Information System (INIS)

Murase, Kenya; Nanjo, Takafumi; Ii, Satoshi; Miyazaki, Shohei; Hirata, Masaaki; Sugawara, Yoshifumi; Kudo, Masayuki; Sasaki, Kousuke; Mochizuki, Teruhito

2005-01-01

The purpose of this study was to investigate the effect of x-ray tube current on the accuracy of cerebral perfusion parameters obtained by CT perfusion studies using multi-detector row CT (MDCT). Following the standard CT perfusion study protocol, continuous (cine) scans (1 s/rotation x 60 s) consisting of four 5 mm thick contiguous slices were performed using an MDCT scanner with a tube voltage of 80 kVp and a tube current of 200 mA. We generated the simulated images with tube currents of 50 mA, 100 mA and 150 mA by adding the corresponding noise to the raw scan data of the original image acquired above using a noise simulation tool. From the original and simulated images, we generated the functional images of cerebral blood flow (CBF), cerebral blood volume (CBV) and mean transit time (MTT) in seven patients with cerebrovascular disease, and compared the correlation coefficients (CCs) between the perfusion parameter values obtained from the original and simulated images. The coefficients of variation (CVs) in the white matter were also compared. The CC values deteriorated with decreasing tube current. There was a significant difference between 50 mA and 100 mA for all perfusion parameters. The CV values increased with decreasing tube current. There were significant differences between 50 mA and 100 mA and between 100 mA and 150 mA for CBF. For CBV and MTT, there was also a significant difference between 150 mA and 200 mA. This study will be useful for understanding the effect of x-ray tube current on the accuracy of cerebral perfusion parameters obtained by CT perfusion studies using MDCT, and for selecting the tube current