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1.
J Mater Chem B ; 8(6): 1146-1156, 2020 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-32011620

RESUMO

A paper-based platform was developed and tested for studies on basic cell culture, material biocompatibility, and activity of pharmaceuticals in order to provide a reliable, robust and low-cost cell study platform. It is based upon a paper or paperboard support, with a nanostructured latex coating to provide an enhanced cell growth and sufficient barrier properties. Wetting is limited to regions of interest using a flexographically printed hydrophobic polydimethylsiloxane layer with circular non-print areas. The nanostructured coating can be substituted for another coating of interest, or the regions of interest functionalized with a material to be studied. The platform is fully up-scalable, being produced with roll-to-roll rod coating, flexographic and inkjet printing methods. Results show that the platform efficiency is comparable to multi-well plates in colorimetric assays in three separate studies: a cell culture study, a biocompatibility study, and a drug screening study. The color intensity is quantified by using a common office scanner or an imaging device and the data is analyzed by a custom computer software without the need for expensive screening or analysis equipment.


Assuntos
Materiais Revestidos Biocompatíveis/economia , Dimetilpolisiloxanos/economia , Teste de Materiais , Papel , Preparações Farmacêuticas/economia , Células Cultivadas , Materiais Revestidos Biocompatíveis/química , Dimetilpolisiloxanos/química , Avaliação Pré-Clínica de Medicamentos , Humanos , Interações Hidrofóbicas e Hidrofílicas , Tamanho da Partícula , Preparações Farmacêuticas/química , Propriedades de Superfície
2.
Nano Lett ; 18(1): 64-69, 2018 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-29207241

RESUMO

Confinement of electrons in graphene to make devices has proven to be a challenging task. Electrostatic methods fail because of Klein tunneling, while etching into nanoribbons requires extreme control of edge terminations, and bottom-up approaches are limited in size to a few nanometers. Fortunately, its mechanical flexibility raises the possibility of using strain to alter graphene's properties and create novel straintronic devices. Here, we report transport studies of nanowires created by linearly-shaped strained regions resulting from individual folds formed by layer transfer onto hexagonal boron nitride. Conductance measurements across the folds reveal Coulomb blockade signatures, indicating confined charges within these structures, which act as quantum dots. Along folds, we observe sharp features in traverse resistivity measurements, attributed to an amplification of the dot conductance modulations by a resistance bridge incorporating the device. Our data indicates ballistic transport up to ∼1 µm along the folds. Calculations using the Dirac model including strain are consistent with measured bound state energies and predict the existence of valley-polarized currents. Our results show that graphene folds can act as straintronic quantum wires.

3.
Aliment Pharmacol Ther ; 42(7): 912-21, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26235444

RESUMO

BACKGROUND: Increased life expectancy in sickle cell disease (SCD) has resulted in greater recognition of the consequences of repeated intravascular vaso-occlusion and chronic haemolysis to multiple organ systems. AIM: To report the long-term consequences of liver dysfunction in SCD. METHODS: A cohort of SCD patients was prospectively evaluated at the National Institutes of Health (NIH) Clinical Center. The association of mortality with liver enzymes, parameters of liver synthetic function and iron overload was evaluated using Cox regression. RESULTS: Exactly, 247 SCD patients were followed up for 30 months of whom 22 (9%) died. After controlling for predictors, increased direct bilirubin (DB), ferritin, alkaline phosphatase and decreased albumin were independently associated with mortality. In a multivariable model, only high DB and ferritin remained significant. Ferritin correlated with hepatic iron content and total blood transfusions but not haemolysis markers. Forty patients underwent liver biopsies and 11 (28%) had fibrosis. Twelve of 26 patients (48%) had portal hypertension by hepatic venous pressure gradient (HVPG) measurements. All patients with advanced liver fibrosis had iron overload; however, most patients (69%) with iron overload were without significant hepatic fibrosis. Ferritin did not correlate with left ventricular dysfunction by echocardiography. DB correlated with bile acid levels suggesting liver pathology. Platelet count and soluble CD14 correlated with HVPG indicating portal hypertension. CONCLUSIONS: Ferritin and direct bilirubin are independently associated with mortality in sickle cell disease. Ferritin likely relates to transfusional iron overload, while direct bilirubin suggests impairment of hepatic function, possibly impairing patients' ability to tolerate systemic insults.


Assuntos
Anemia Falciforme/complicações , Anemia Falciforme/mortalidade , Hepatopatias/complicações , Hepatopatias/mortalidade , Adolescente , Adulto , Idoso , Anemia Falciforme/sangue , Feminino , Ferritinas/sangue , Humanos , Ferro/sangue , Sobrecarga de Ferro/sangue , Sobrecarga de Ferro/complicações , Sobrecarga de Ferro/mortalidade , Cirrose Hepática/sangue , Cirrose Hepática/complicações , Cirrose Hepática/mortalidade , Hepatopatias/sangue , Masculino , Pessoa de Meia-Idade , Estados Unidos/epidemiologia , Adulto Jovem
4.
J Phys Condens Matter ; 27(17): 175301, 2015 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-25836340

RESUMO

We study transport properties of hexagonal zigzag graphene quantum rings connected to semi-infinite nanoribbons. Open two-fold symmetric structures support localized states that can be traced back to those existing in the isolated six-fold symmetric rings. Using a tight-binding Hamiltonian within the Green's function formalism, we show that an external magnetic field promotes these localized states to Fano resonances with robust signatures in transport. Local density of states and current distributions of the resonant states are calculated as a function of the magnetic flux intensity. For structures on corrugated substrates we analyze the effect of strain by including an out-of-plane centro-symmetric deformation in the model. We show that small strains shift the resonance positions without further modifications, while high strains introduce new ones.

5.
Eur J Pharm Sci ; 44(5): 635-42, 2011 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-22033152

RESUMO

Extrusion-spheronization (ES) is a frequently used agglomeration process in the pharmaceutical industry to manufacture spherical solid units or pellets with a narrow size and shape distribution. In this study, photometric stereo imaging was applied in real-time during the final steps of the ES process, being spheronization and drying. In addition to the pellet size distribution of undispersed (wet) samples, the imaging technique captures visual information on pellet shape and surface brightness. Pellet samples were taken at 20 time points during spheronization and were imaged at-line (during spheronization) and off-line (after spheronization). Particle size distributions and visual image information were both used to characterise the spheronization behaviour of different formulations. Next, particle size distributions and surface brightness values calculated from the at-line obtained images during fluid bed drying of pellets were analysed. The particle size distribution and brightness value changes occurring during pellet drying were explained both by the reduction in residual moisture content and drug solid-state transition. Due to the rapidness of the technique with regard to sample preparation, sample measurement and the acquisition of results in combination with the possibility to measure undispersed (wet) samples, valuable information on spheronization and drying characteristics of different formulations was obtained in real-time.


Assuntos
Química Farmacêutica/métodos , Celulose/química , Dessecação , Tamanho da Partícula , Análise Espectral Raman , Teofilina/química , Água/análise
6.
Eur J Pharm Biopharm ; 66(3): 466-74, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17257816

RESUMO

This study aimed to assess the suitability of two widely utilized solid state characterization techniques namely powder X-ray diffraction (XRPD) and Raman spectroscopy, in polymorph detection and quantification for carbamazepine anhydrate and dihydrate mixtures. The influences of particle size, particle morphology, mixing, and in particular, surface bias on quantitation were investigated. Binary mixtures of carbamazepine anhydrate (form III) and dihydrate were prepared and analyzed using both XRPD and Raman spectroscopy in combination with partial least squares analysis. It was found that in principle both XRPD and Raman spectroscopy could be used to build calibration models for quantitative analysis, and a satisfactory correlation between the two techniques could be achieved. However, Raman spectroscopy appeared to be a more reliable quantification method because problems such as different particle size, morphology, and special distribution of the two solid state forms of the drug seemed to have no significant influence on Raman scattering in this study. The robust nature of Raman analysis greatly facilitates the whole quantification process from the preparation of calibration models to the quantification of in situ CBZ-DH conversion.


Assuntos
Carbamazepina/química , Calibragem , Química Farmacêutica , Tamanho da Partícula , Difração de Pó , Análise Espectral Raman , Difração de Raios X
7.
Eur J Pharm Biopharm ; 64(3): 326-35, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16846721

RESUMO

Visual observations of the hydration process of single carbamazepine (CBZ) crystals in water and in various excipient solutions [(1% w/v) - hydroxypropyl cellulose (HPC), poly(vinyl pyrrolidone) (PVP), sodium carboxymethylcellulose (CMC) at pH 7.5 and 3.0, and polyethylene glycol (PEG)] using scanning electron microscopy (SEM) are reported in this paper. Raman microscopy was used to confirm the chemical structures of the unconverted CBZ and the CBZ dihydrate (DH) needles. It was found that defect structures were a more important driving force than the nature of crystal faces for the initiation of the hydration, but face differences became obvious after 6 h immersion. The biggest crystal face grown from methanol, (100), was the slowest one to be covered with DH needles. A comparison of the molecular arrangements along the three crystal faces [(100), (010) and (001)] was carried out using crystal structure visualization software, and fewer polar groups exposed on the (100) face than on the (001) and (010) faces were found, explaining the comparatively weak interaction of the (100) face with water during hydration. Furthermore, investigation of the influence of excipients on the hydration of CBZ showed that both HPC and PVP strongly inhibited conversion, and no conversion of CBZ to DH was found after 18 h immersion in water. PEG and CMC (pH 7.5) were less potent inhibitors than HPC and PVP, and DH needles were observed on all the faces except the (100) face after 18 h immersion. No conversion was detected for the crystal immersed in CMC solution at pH 3.0. This is likely to be caused by the decreased polarity of CMC in water at pH 3.0 (pKa,cmc = 4.3), and thus a higher surface adsorption of CMC to the CBZ crystals in dispersion. The influence of excipients on the conversion of CBZ observed in this study agreed well with our previous quantitative studies using Raman spectroscopy. In this study, visual observation using electron microscopy has been demonstrated to be a unique and powerful tool to improve our understanding of polymorphic conversions of CBZ in aqueous suspension.


Assuntos
Carbamazepina/química , Excipientes/química , Análise de Fourier , Microscopia Eletrônica de Varredura , Análise Espectral Raman , Carboximetilcelulose Sódica/química , Celulose/análogos & derivados , Celulose/química , Cristalização , Modelos Moleculares , Estrutura Molecular , Polietilenoglicóis/química , Povidona/química , Soluções , Fatores de Tempo , Água/química
9.
J Oral Maxillofac Surg ; 59(6): 603-11; discussion 611-2, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11381378

RESUMO

PURPOSE: The Bispectral Index (BIS) has been recently shown to objectively predict the level of sedation in patients undergoing conscious sedation. It was the goal of this study to directly compare the recovery profile of patients where the BIS was used to monitor sedation with a control group where the monitor was not used. PATIENTS AND METHODS: Forty patients undergoing third molar extractions under intravenous conscious sedation were randomly assigned to 2 groups. In both groups, induction of sedation was performed using a standard dose of fentanyl (1.5 microg/kg) and midazolam (0.05 mg/kg). Propofol was then given in 10 to 20 mg boluses until a clinically desirable sedation level was achieved. In 1 group, the BIS was then monitored continually during surgery using a microcomputer (Aspect-1050 Monitor, Aspect Co, Natick, MA) and recorded at 5-minute intervals. The anesthetist (N.A.S.) provided additional propofol boluses to maintain a BIS level of 70 to 80. In the other group, the BIS sensor was applied, but the monitor was not used. In this group, the sedation was modified, and additional propofol was given based solely on the anesthetist's subjective assessment of the desired level of sedation (Observer's Assessment of Alertness/Sedation [OAA/S] scale level 2 to 3). Additional boluses of 1 mg of midazolam were given during the procedure if patients required repeated boluses of propofol at less than 5-minute intervals to maintain the desired sedation level (BIS level of 70 to 80 or OAA/S level of 2 to 3). These additional midazolam boluses, as well as the time of the last sedative dose (propofol or midazolam) were recorded to study the effect of these factors on recovery. RESULTS: Of the 40 patients initially included in the study, 1 subject in the BIS-monitored group was excluded due to the loss of intravenous access at initiation of the case. For the remaining 39 subjects, 19 were assessed objectively using the BIS monitor, whereas 20 were assessed subjectively using the OAA/S scale. The BIS cases were slightly longer in duration than the OAA/S cases, lasting an average of 26 minutes versus 22 minutes. This difference was statistically nonsignificant (P =.19). Less propofol was used in the BIS cases, with an average of 98 mg for BIS cases versus 106 mg for OAA/S cases (P =.59). The total dose in mg/kg/min was significantly less in the BIS group (0.054 mg/kg/min) than in the OAA/S group (0.074 mg/kg/min; P =.0082). There was no significant difference in the amount of midazolam administered after induction between the 2 groups (P =.60). The surgeon, who was blinded to whether the monitor was used, ranked the third molar extractions more difficult in the BIS group (P =.05). However, patients in the BIS group were on average more cooperative, with better maintenance of muscle tone. The difference in these parameters were nonsignificant (P =.15 and .092, respectively). A positive Romberg test was obtained earlier in BIS patients, although this difference was nonsignificant (P =.097). The straight-line test was completed significantly sooner in BIS patients (P =.013). There was no significant difference between the BIS and OAA/S groups in perceptual speed (P =.55) or computation (P =.32). There was essentially no difference between groups in patient-assessed comfort or recall of the procedure. There were also no notable differences in anesthesia complications, return to activities of daily life, or pain medication use between the 2 groups. CONCLUSIONS: The BIS provides additional information for standard monitoring techniques that helps guide the administration of sedative-hypnotic agents. It appears that use of the BIS monitor can help to titrate the level of sedation so that less drugs are used to maintain the desired level. The trend toward an earlier return of motor function in BIS-monitored patients warrants further investigation.


Assuntos
Período de Recuperação da Anestesia , Anestesia Dentária , Sedação Consciente/métodos , Eletroencefalografia/métodos , Monitorização Intraoperatória , Adulto , Anestesia Intravenosa , Anestésicos Intravenosos/administração & dosagem , Conscientização , Feminino , Fentanila/administração & dosagem , Humanos , Hipnóticos e Sedativos/administração & dosagem , Masculino , Midazolam/administração & dosagem , Dente Serotino/cirurgia , Extração Dentária
11.
J Oral Maxillofac Surg ; 58(4): 364-8; discussion 369, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10759114

RESUMO

PURPOSE: The bispectral (BIS) index has been used to interpret electroencephalogram (EEG) recordings to predict the level of sedation and loss of consciousness in patients undergoing general anesthesia. It was the purpose of this project to assess the usefulness of BIS technology in determining the level of sedation in patients undergoing third molar extraction under conscious sedation. PATIENTS AND METHODS: Twenty-five subjects undergoing third molar extraction in an outpatient setting were analyzed. The EEG activity was recorded continually during surgery using a microcomputer (Aspect-1050 Monitor; Aspect Co, Natick, MA) with real-time bispectral data obtained by EEG skin electrodes through a frontotemporal montage. The Observer's Assessment of Alertness and Sedation (OAA/S) scale was used to subjectively assess the level of sedation observed by the anesthetist before initiating the sedation procedure and then at 5-minute intervals until the end of the procedure. The BIS level was simultaneously recorded. The initial sedation was accomplished using a standard dose of midazolam (0.05 mg/kg) and fentanyl (1.5 microg/kg) followed by a 10- to 30-mg bolus of propofol until a level of sedation at which the patient's eyes were closed and he or she was responsive only to vigorous stimulation or repeated loud calling of their name (OAA/S level of 1 to 2). Local anesthesia was then administered. Additional doses of sedative medication (midazolam or propofol) were given during the procedure to maintain the desired level of sedation (an OAA/S level of 2 to 3). The time and dose of the drug given were recorded. The level of sedation based on a single anesthetist's interpretation (OAA/S) and the BIS readings were then compared. RESULTS: A strong positive relationship between the BIS index and OAA/S readings was found (P < .0001). Pairwise comparisons of mean BIS index and its corresponding OAA/S level were significantly different from each other (P < .003) except for OAA/S levels 2 and 3 (P = .367). CONCLUSION: BIS technology offers an objective, ordinal means of assessing the depth of sedation. There was a strong relationship between the objective BIS values and subjective assessment (OAA/S scale) of the depth of anesthesia. This can be invaluable in providing an objective assessment of sedation in oral and maxillofacial surgery where it may be difficult to determine the level of sedation clinically.


Assuntos
Anestesia Dentária/métodos , Sedação Consciente , Eletroencefalografia/efeitos dos fármacos , Dente Serotino/cirurgia , Extração Dentária , Adolescente , Adulto , Anestésicos Intravenosos/administração & dosagem , Anestésicos Locais/administração & dosagem , Relação Dose-Resposta a Droga , Overdose de Drogas/prevenção & controle , Feminino , Fentanila/administração & dosagem , Humanos , Hipnóticos e Sedativos/administração & dosagem , Masculino , Midazolam/administração & dosagem , Monitorização Intraoperatória , Propofol/administração & dosagem , Processamento de Sinais Assistido por Computador
12.
Anesth Prog ; 47(3): 72-83, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11432160

RESUMO

The bispectral (BIS) index has been used to interpret partial EEG recordings to predict the level of sedation and loss of consciousness in patients undergoing general anesthesia. The author has evaluated BIS technology in determining the level of sedation in patients undergoing outpatient deep sedation. These experiences are outlined in this review article. Initially, the correlation of the BIS index with traditional subjective patient evaluation using the Observer's Assessment of Alertness and Sedation (OAA/S) scale was performed in 25 subjects. In a second study, the recovery profile of 39 patients where the BIS was used to monitor sedation was compared with a control group where the monitor was not used. A strong positive relationship between the BIS and OAA/S readings was found in the initial subjects. From the recovery study, it appears that use of the BIS monitor may help titrate the level of sedation so that less drugs are used to maintain the desired level of sedation. A trend to earlier return of motor function in BIS-monitored patients was also demonstrated. BIS technology offers an objective, ordinal means of assessing the depth of sedation. This can be invaluable in comparing studies of techniques. The BIS index provides additional information to standard monitoring techniques that helps guide the administration of sedative-hypnotic agents. The trend to earlier return of motor function in BIS-monitored patients warrants further investigation.


Assuntos
Procedimentos Cirúrgicos Ambulatórios , Anestesia Dentária , Anestesia Geral , Eletroencefalografia , Hipnóticos e Sedativos/administração & dosagem , Processamento de Sinais Assistido por Computador , Adolescente , Adulto , Período de Recuperação da Anestesia , Anestésicos Intravenosos/administração & dosagem , Cognição/efeitos dos fármacos , Estado de Consciência/efeitos dos fármacos , Feminino , Fentanila/administração & dosagem , Humanos , Masculino , Rememoração Mental/efeitos dos fármacos , Midazolam/administração & dosagem , Dente Serotino/cirurgia , Medição da Dor , Propofol/administração & dosagem , Desempenho Psicomotor/efeitos dos fármacos , Estatística como Assunto , Fatores de Tempo , Extração Dentária , Vigília/efeitos dos fármacos
13.
Anesth Prog ; 47(3): 84-6, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11432161

RESUMO

Additional observations were made in the use of the bispectral (BIS) index with the use of ketamine and in performing general anesthesia without the use of local anesthesia in nonintubated patients. Twenty-five subjects undergoing extraction procedures in an outpatient setting were analyzed using bispectral analysis with ketamine and midazolam. Despite repeated injections of midazolam during the procedure, only transient decreases of the BIS occurred to the 80s, with a low value of 77 in all but 1 patient where ketamine was used. In comparison, values in the 50-70 range are typically seen immediately after the administration of sedative doses of midazolam, propofol, or methohexital. In the second study, once propofol anesthesia was initiated, BIS readings in the 30s were commonly seen in patients during their procedure. The lowest BIS level observed was 18. Bispectral analysis was useful to trend the present anesthetic state and adjust the dose of propofol accordingly. In no case was laryngospasm or total airway obstruction observed. In 1 case, partial airway obstruction secondary to retro-positioning of the tongue occurred with a subsequent decrease in oxygen saturation to 89%. This was rectified by repositioning the patient to alleviate the obstruction. Consistent with previous studies utilizing ketamine, BIS values are consistently higher when compared with other hypnotic agents. With the subsequent injection of midazolam, the BIS level did not decrease to anticipated levels. In the final study reviewed, when local anesthesia was not used during general anesthesia, bispectral analysis was a useful adjunct in helping maintain a steady state of general anesthesia in nonintubated patients undergoing third molar extractions. Bispectral analysis offers additional information on the depth of the hypnotic state and is useful in helping control the depth of anesthesia. A limitation of the index includes the inability to titrate the level of sedation induced by hypnotic agents such as midazolam when ketamine is concomitantly administered.


Assuntos
Anestesia Dentária , Anestesia Geral , Anestésicos Dissociativos/administração & dosagem , Eletroencefalografia , Ketamina/administração & dosagem , Processamento de Sinais Assistido por Computador , Obstrução das Vias Respiratórias/prevenção & controle , Procedimentos Cirúrgicos Ambulatórios , Anestesia Local , Anestésicos Intravenosos/administração & dosagem , Humanos , Laringismo/prevenção & controle , Metoexital/administração & dosagem , Midazolam/administração & dosagem , Dente Serotino/cirurgia , Propofol/administração & dosagem , Extração Dentária
15.
J Oral Maxillofac Surg ; 57(9): 1058-65; discussion 1065-7, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10484106

RESUMO

PURPOSE: This study evaluated the subjective and objective findings in patients who had undergone temporomandibular joint (TMJ) reconstruction with a temporalis myofascial flap. All joints had previously been reconstructed with alloplastic, allogeneic, or autogenous material. PATIENTS AND METHODS: Twenty-three consecutive patients who underwent 28 temporalis myofascial flap procedures were assessed subjectively and objectively preoperatively and at an average of 36 months postoperatively. Panoramic radiographs, magnetic resonance imaging (MRI), or coronal computed axial tomography scans (CT scans) were performed on all patients preoperatively to evaluate for joint disease. A visual analog scale (VAS) was used to assess pain preoperatively and postoperatively. Patients also reported their use of pain medication, ability to function, diet, complications, and overall satisfaction. Preoperative and postoperative objective assessment consisted of an evaluation of range of motion, deviation on opening, joint noise on function, and cosmesis. RESULTS: On preoperative radiographic examination, 24 of 28 joints showed signs of bony degeneration, including cortical erosion, condylar flattening, and joint space alterations. Four joints showed evidence of ankylosis. The average preoperative maximal interincisal opening (MIO) was 23.7 mm, and the postoperative average was 32.3 mm (P<.05). Preoperatively, all patients displayed one or more objective clinical signs of joint disease such as joint noise on function, deviation on opening, limited mouth opening (less than 20 mm), or limited excursions (less than 2 mm). Postoperatively, 65% displayed one or more of these signs, a significant reduction (P<.05). Preoperatively, the average pain score was 8.2 on the VAS, and postoperatively the average pain score was 3.4 (P<.0005). Fifteen patients used less pain medication postoperatively, 7 used the same amount, and 1 patient used more. Thirteen patients were very satisfied with the overall results of the surgery, 4 were satisfied, and 4 were not satisfied. Two patients were satisfied with their increased function but were not satisfied with their pain reduction. All were satisfied with their cosmetic appearance. Minor complications after the procedure included 3 patients who had preauricular paresthesia and 1 who had an intraoperative dura mater exposure without sequelae. Two patients had postoperative superficial suture infections, and 2 noted hearing changes that were found to be clinically insignificant by audiologic examination. CONCLUSION: The temporalis myofascial flap is an autogenous graft that has the advantages of close proximity to the temporomandibular joint, minimal surgical morbidity, and successful clinical results. It was found to be a valuable option for TMJ reconstruction in joints in which alloplastic, allogeneic, or autogenous materials have previously been placed unsuccessfully.


Assuntos
Avaliação de Resultados em Cuidados de Saúde/métodos , Retalhos Cirúrgicos , Músculo Temporal/transplante , Transtornos da Articulação Temporomandibular/cirurgia , Articulação Temporomandibular/cirurgia , Adulto , Anquilose/etiologia , Anquilose/cirurgia , Artroplastia de Substituição/efeitos adversos , Feminino , Humanos , Pessoa de Meia-Idade , Medição da Dor , Satisfação do Paciente , Amplitude de Movimento Articular , Reoperação
16.
J Oral Maxillofac Surg ; 57(4): 399-403, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10199491

RESUMO

PURPOSE: The goal of the current study was to evaluate the ability to diagnose the presence of an inferior orbital wall fracture through the use of a transantral endoscopy technique at bedside. PATIENTS AND METHODS: Seven trauma patients with initial axial computed tomography (CT) scan findings consistent with an orbital floor fracture were studied. Before endoscopy, the patients underwent a coronal CT scan with 3-mm cuts for later comparison with the endoscopic findings. The surgeon performing the endoscopy procedure was blinded to the results of the coronal CT scan. Visual acuity, intraocular pressure, and measurement for enophthalmos were performed before endoscopy. The endoscopic procedure was performed at the bedside using local anesthesia. A trocar was used in the canine fossa to gain access to the maxillary sinus. A 30 degrees and then a 70 degrees endoscope were introduced through the trocar to evaluate the integrity of the orbital floor (ie, maxillary sinus roof). The degree of mucosal injury of the orbital floor and the presence of blood or orbital contents in the sinus were recorded. The ophthalmologic examination was repeated after completion of endoscopy. RESULTS: The endoscopic procedure was able to be completed in all patients. There was no change in the ophthalmologic examination in any patient as a result of endoscopy. In six of the seven patients studied, the endoscopic findings correlated with the need for surgical intervention to repair the orbital floor predicted on the basis of coronal CT scan. This was determined by the degree of injury to the orbital floor and the presence of hematoma, exposed bone, or fat. In the remaining case, endoscopy was not diagnostic for the presence of a fracture because only ecchymosis of the orbital floor was noted. CONCLUSIONS: The ability to perform endoscopy under local anesthesia at the bedside is useful in those trauma patients whose concomitant injuries may prohibit other diagnostic modalities.


Assuntos
Seio Maxilar , Fraturas Orbitárias/diagnóstico , Ferimentos não Penetrantes/diagnóstico , Adolescente , Adulto , Anestesia Local , Endoscopia/métodos , Estudos de Avaliação como Assunto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Órbita/diagnóstico por imagem , Tomografia Computadorizada por Raios X
17.
J Invertebr Pathol ; 72(3): 206-13, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9784342

RESUMO

Bacillus thuringiensis israelensis delta-endotoxin genes were inserted into transposon Tn917 in plasmid pTV51Ts and cloned into the chromosome of Bacillus sphaericus 2362. Many of the transformants reacted with antibody to the 135-, 128-, 65-, and 28-kDa B.t.israelensis toxin proteins and were approximately 10 times more toxic to A. aegypti larvae than the untransformed host. Some of the transformants differed physiologically and morphologically from the wild-type B. sphaericus. The toxicity of the transformed phenotype was maintained through many transfers in the absence of selective pressure. Copyright 1998 Academic Press.

18.
J Oral Maxillofac Surg ; 56(10): 1124-7; discussion 1127-8, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9766535

RESUMO

PURPOSE: Methohexital and propofol have been shown to be effective agents for continuous intravenous infusion to produce conscious sedation during oral surgical procedures. The current study was conducted to compare these techniques for intraoperative cardiopulmonary stability, patient cooperation, amnesia, comfort, recovery time, and postoperative nausea and vomiting. METHODS: Seventy ASA Class I or Class II patients between the ages of 18 and 40 years, scheduled for surgical extraction of impacted third molars, were entered into the study. Thirty-five patients were assigned to group A (methohexital) and 35 were assigned to group B (propofol). Intravenous sedation was accomplished using premedication with 1.5 microg/kg of fentanyl and 0.05 mg/kg of midazolam followed by the continuous infusion of methohexital or propofol at a rate of 50 microg/kg/min. The infusion was then titrated to 100 microg/kg/min to accomplish a level of sedation in which the eyes were closed and the patients were responsive to verbal commands. Subjects were monitored for variability of heart rate, blood pressure, oxygen saturation, amnesia, comfort, cooperation, nausea and vomiting, and recovery time based on cognitive, perceptual, and psychomotor tests. RESULTS: There was no statistical difference between the two medication groups except for heart rate, which was found to increase by 11 beats/min for group A and only three beats/min in group B. CONCLUSION: A continuous infusion technique using either methohexital or propofol (50 to 100 microg/kg/min) was found to be safe and effective, with no clinically significant differences in cooperation, cardiopulmonary stability, recovery time, amnesia, comfort, and the incidence of nausea or vomiting. However, the cost-effectiveness of methohexital is superior to that of propofol.


Assuntos
Anestesia Dentária/métodos , Anestésicos Intravenosos/farmacologia , Sedação Consciente/métodos , Metoexital/farmacologia , Propofol/farmacologia , Adolescente , Adulto , Período de Recuperação da Anestesia , Anestésicos Intravenosos/administração & dosagem , Pressão Sanguínea/efeitos dos fármacos , Método Duplo-Cego , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Infusões Intravenosas , Masculino , Memória/efeitos dos fármacos , Metoexital/administração & dosagem , Análise Multivariada , Oxigênio/sangue , Cooperação do Paciente , Propofol/administração & dosagem , Respiração/efeitos dos fármacos
19.
J Oral Maxillofac Surg ; 56(5): 534-43; discussion 543-4, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9590334

RESUMO

PURPOSE: The goal of this study was to evaluate the presence of the inflammatory cytokines interleukin-1 beta (IL-1 beta), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-alpha) within the superior temporomandibular joint (TMJ) space in patients with internal derangements and to compare these values with the pathologic findings seen arthroscopically. PATIENTS AND METHODS: Thirty patients with symptomatic TMJ dysfunction and clinical and imaging evidence of internal derangements of the TMJ were evaluated. Before entering the superior joint space with the arthroscope, 2 mL sterile saline was injected and, after 30 seconds of equilibration, was aspirated for analysis. The surgeon then performed diagnostic arthroscopy. The degree of synovitis, degeneration, percent condylar roofing, and any pathologic changes, such as perforations, were recorded. The level of total protein in each sample was ascertained, as well as the levels of IL-1 beta, IL-6, and TNF-alpha. RESULTS: Of 30 samples tested, three were discarded because of failure to gain access into the superior joint space. Of the 27 remaining samples, IL-6 showed the closest correlation with the level of acute synovitis demonstrated arthroscopically. Two of the higher IL-6 levels (167 and 324 pg/microg protein) were seen with patients with a significant disc perforation. In patients with a high degree of vascularity, IL-6 was found to be between 0 to 581 pg/microg protein with an average of 80 pg/microg protein and a median value of 43 pg/mg. These values significantly correlated with the degree of vascularity (P < or = .02). This is in comparison with the 10 remaining patients, who showed significantly fewer vascular changes arthroscopically. In these patients, the range of IL-6 was 0 to 35 pg/microg protein, with an average of 19 pg/microg protein and a median value of 14.5 pg/microg. These values significantly correlated with the smaller degree of vascularity (P < or = .02). In seven patients, the role of nonsteroidal antiinflammatory drug (NSAID) use resulted in decreased levels of IL-6, which has been noted in previous studies. In patients with higher rated redundancy of the synovial tissue, the average IL-6 level was 92 pg/microg protein, whereas the median value was 44 pg/microg protein. In patients with little or no redundant synovial tissue, an average IL-6 level of 22 pg/microg protein was present. The median value in these same joints was 15 pg/microg protein. These IL-6 values significantly correlated with the degree of redundancy (P < or = .03). The degree of degenerative change (chondromalacia, fibrillation), disc displacement (roofing), and the presence or absence of adhesions did not significantly affect the levels of IL-6 within the patients studied. The presence of IL-1 beta and TNF-alpha was not found to correlate with the arthroscopic findings in the superior joint space. CONCLUSIONS: The presence of IL-6 correlated with the degree of acute synovitis. IL-1 beta and TNF-alpha were not found in significant levels within the superior joint space. These findings correlated with those reported by other investigators. The production of IL-6 by synovial cells and its role in TMJ disease warrants further investigation.


Assuntos
Artroscopia , Citocinas/análise , Mediadores da Inflamação/análise , Síndrome da Disfunção da Articulação Temporomandibular/imunologia , Adolescente , Adulto , Idoso , Artroscopia/métodos , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Interleucina-1/análise , Interleucina-6/análise , Masculino , Pessoa de Meia-Idade , Líquido Sinovial/química , Articulação Temporomandibular/imunologia , Síndrome da Disfunção da Articulação Temporomandibular/cirurgia , Fator de Necrose Tumoral alfa/análise
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