bluuebunny/crossref_metadata_2025 huggingface dataset:
Technetium-99m ceftizoxime kit preparation
Authors: Diniz Simone Odília Fernandes , Siqueira Cristiano Ferrari , Nelson David Lee , Martin-Comin Josep , Cardoso Valbert Nascimento
Published: January 2006

The aim of this work was to prepare a kit of 99mTc-ceftizoxime (99mTc-CFT), with stability and biological activity preserved, able to identify a septic focus (E. coli) in the experimental infection model in rats. The preparation of the CFT kit involved the use of lyophilized solutions containing the antibiotic ceftizoxime and the sodium dithionite reducing agent (6.0 mg/mL). After lyophilization, the kit was reconstituted with 1.0 mL of sodium 99mTc-pertechnetate solution (Na99mTcO4-) with an activity of 370 MBq. The solution was boiled for 10 min and filtered through a cellulose ester filter. The labeling efficiency was on the order of 92%, remaining stable for six hours and the kit remained stable for two months. The biological activity of the 99mTc-CFT was evaluated by diffusion in agar impregnated with E.coli and S. aureus. Seven Wistar rats, weighing from 200 to 250 g, were used for the development of the septic focus. After 24 hours from the induction of the infectious site (E.coli), the animals were anesthetized and 0.1 mL of 99mTc-CFT (37 MBq) was injected into the tail veins of the animals. The images were obtained with a gamma camera one, two and six hours after injection and the regions of interest (ROIs) were calculated. The diameters of the inhibition halos for 99mTc-CFT were 27.16 ± 0.23 and 27.17 ± 0.20 for S.aureus and E.coli, respectively, while those for the unlabeled CFT were 30.4 ± 0.33 and 29.43 ± 0.26, respectively. The results for the biodistribution of 99mTc-CFT in infected animals furnished a ratio of 1.97 ± 0.31, 2.10 ± 0.42 and 2.01 ± 0.42 for cpm-target/cpm-no target for the one, two and six-hour periods, respectively. The images showed a clear uptake of labeled antibiotic (99mTc-CFT) by the infectious site during the experiment. The results attest to the viability of producing a kit with 99m technetium-labeled ceftizoxime for the investigation of infectious processes.
Scintigraphic diagnosis of infectious complications in renal failure patients undergoing hemodialysis, continuous ambulatory peritoneal dialysis or renal transplant
Authors: Vicente Ana María García , Solís Sebastián Ruiz , Castrejón Angel Soriano , García Víctor Manuel Poblete , Rubio Maria del Prado Talavera , Marina Sonia Rodado , Romera Montserrat Cortés
Published: January 2006

Patients with end-stage renal disease have two therapeutic options, dialysis and renal transplantation. Infectious complications occurring in such patients will not only condition the effectiveness of such treatments, but are among the main causes of morbidity and mortality in such cases. Knowledge of the advantages and limitations of nuclear techniques is essential for management of these conditions.
The surgical viability and radiological monitoring of brain implants of bioactive micro-seeds in an animal model
Authors: Silva Giane X. O. , Campos Tarcisio Passos Ribeiro de , Siqueira Sávio Lana , Maciel Marcelo B.
Published: January 2006

The interstitial implant is a therapeutic modality in brachytherapy of the head and neck. Presently, the seeds implanted in tumors in the central nervous system are metallic I-125. After the full emission of the radionuclide, the seed remains inert in the implanted area. Bioactive ceramic seeds have been prepared for this research group incorporating Sm-152 to be active in Sm-153. The main goal of the present study is the development of a the surgical technique for implanting the biodegradable radioactive micro-seeds in the brains of rabbits, as well as the observation of the clinical reactions of the animal after implantation of two sets of three seeds. The surgical procedure consisted of performing two separate perforations 10 mm from each other in the skull, permitting the implantation of two groups of three seeds, totaling six seeds. The results of the pilot study showed the effectiveness of the surgical procedure and of the biocompatibility of the seeds and the lack of presence of adverse reactions, functional sequels, or inflammation in a follow up 50 days post-surgery. Such seeds of reduced volume, 0.2 x 1.6 mm, could be monitored by computerized tomography 30 days after implanting.
Advances in bacterial specific imaging
Authors: Wareham David , Michael J. , Das Satya
Published: January 2006

Nuclear medicine is a powerful diagnostic technique able to detect inflammatory foci in human disease. A wide range of agents have been evaluated for their ability to distinguish lesions due to microbial infection from those due to sterile inflammation. Advances continue to be made on the use of radiolabelled antibiotics which as well as being highly specific in the diagnosis of infection may be useful in monitoring the treatment and course of disease. Here we provide an update on in-vitro and clinical studies with a number of established and novel radiopharmaceuticals
Dosimetric evaluation in radiation synovectomy
Authors: Lima Carla Flávia de , Campo Tarcisio Passos Ribeiro de
Published: January 2006

Rheumatoid arthritis can manifest itself through synovitis, of which the knee is the common locale. The treatment using an intra-articular radioisotope injection has been applied in various countries. In this work, the dose of radioactive material absorbed in the joint is evaluated, taking into consideration the dose received in the articular cartilage and adjacencies using a three-dimensional voxel model representing the knee. The radioisotopes studied were Samarium-153 and Dysprosium-165. The results show that the synovial membrane receives 85 to 98% of the normalized dose taken from all voxels representative of the synovium. The following features of 153Sm and of 165Dy - its short physical half-life, the gamma emissions with low energy which allow monitoring the injection trough scintigraphy images, the possibility of binding themselves to macroaggregates that are retained in the joint, the high percentage of the effective dose spread in the synovial membrane - make these suitable radioisotopes for radiation synovectomy.
Acetylsalicylic acid and labeling of blood constituents with technetium-99m
Authors: Fonseca Adenilson de Souza da , Frydman Jacques Natan Grinapel , Rocha Vanessa Câmara da , Bernardo-Filho Mario
Published: January 2006

Acetylsalicylic acid is the drug most used an anti-inflammatory agent and for secondary prevention of thrombotic phenomenon. Drugs can modify the labeling of blood constituents with technetium-99m (99mTc). The aim of this work was to evaluate the effect of in vitro or in vivo assays with acetylsalicylic acid on the labeling of the blood constituents with 99mTc. In vitro assay was performed with samples of whole blood from Wistar rats incubated with acetylsalicylic acid (1.0 mg/ml) for one hour before the 99mTc-labeling process. For in vivo assay, Wistar rats were treated with acetylsalicylic acid (1.5 mg/kg) during one hour, and the whole blood was withdrawn for the 99mTc-labeling process. Saline was used in control groups. Data showed that the fixation of 99mTc to the blood constituents was not significantly (p>0.05) modified in in vitro and in vivo assays with acetylsalicylic acid, at least not when the experiments were carried out with the doses normally used in human beings.
Effects of low-dose ionising radiation on pituitary adenoma: is there a role for L-type calcium channel?
Authors: Soares Marcella Araugio , Santos Raquel Gouvêa dos
Published: January 2006

Pituitary adenomas constitute about 6-18% of brain tumours in adults. Activation of voltage gated calcium currents can account for growth hormone oversecretion in some GH-secreting pituitary adenomas that produce an acromegaly appearance and increase mortality. Ca2+ ions, as mediators of intracellular signalling, are crucial for the development of apoptosis. However, the role of [Ca2+] in the development of apoptosis is ambiguous. In this study, the effects of low-dose ionising gamma radiation (60Co) on rat pituitary adenoma cells survival and proliferation and the role of calcium channels on the apoptosis radio-induced were evaluated. Doses as low as 3 Gy were found to inhibit GH3 cell proliferation. Even though there was a significant number of live cells,168 hours following irradiation, they were not able to proliferate. The results indicate that the blockade of extracellular calcium influx through these channels does not interfere in the radiation-induced apoptosis in GH3 cells.
In vitro response of the human breast cancer cell line MDAMB-231 and human peripheral blood mononuclear cells exposed to 60Co at single fraction
Authors: Andrade Lídia Maria , Campos Tarcisio Passos Ribeiro de , Leite M. F. , Góes A. M.
Published: January 2006

Radiotherapy using gamma rays is a common modality of breast cancer treatment. The aim of this research is to investigate the biological response of the human breast cancer cell line MDAMB-231 and human peripheral blood mononuclear cells (PBMC) exposed in vitro to 60 Co irradiation at a single fraction of 10 Gy, 25 Gy and 50 Gy doses at 136,4 cGy.min-1 rate. Cells were irradiated at room temperature by the Theratron 80 radiotherapy system. Biological response was evaluated through cellular viability using MTT assay and nucleus damages visualized by Propidium Iodide assay and electrophoresis agarose gel after gamma irradiation. Nucleus damages induced by 60Co irradiation were compared to damage caused by cell exposure to 10% methanol. The 50 Gy dose of irradiation did not stimulate nuclus damages at the same level as that affected by 10% methanol induction in the MDAMB-231. Further studies are necessary to understand these mechanisms in the MDAMB-231 human breast carcinoma cell line.
Analysis of the 40K levels in soil using gamma spectrometry
Authors: Santos Júnior José Araújo dos , Cardoso Jorge João Ricardo Ferreira , Silva Cleomacio Miguel da , Silveira Suêldo Vita , Amaral Romilton dos Santos
Published: January 2006

Potassium-40 was determined in soil in an area with 40,000 m² situated in the western State of Pernambuco, Brazil. For radiometric measurements, the gamma spectrometry method with a high purity germanium (HPGe) detector was used. Sampling of 78 soil samples has been performed at intervals of 25 m. The specific activities of 40K were calculated based on the photopeak of 1.46 MeV. Values from 541 to 3,572 Bq kg-1 were obtained (mean of 1,827 Bq kg-1). These values allowed the determination of the elemental concentrations as well as the absorbed dose rates in air, 1 m above the ground. The values varied from 1.7 to 11.5% (mean of 6%) and from 23.4 to 154.3 nGy h-1 (mean of 79 nGy h-1), respectively.
Biodistribution of free 99mTc-ovalbumin and 99mTc-ovalbumin encapsulated in liposomes
Authors: Alves Andrea Catão , Gontijo Cristiano Machado , Oliveira Mônica Cristina , Diniz Simone Odília Fernandes , Oliveira Flávia Márcia , Cardoso Valbert Nascimento , Ramaldes Gilson Andrade
Published: January 2006

The oral administration of proteic antigens, like ovalbumin, may result in the induction of oral tolerance or immunization. The aim of this work was to label a protein antigen with 99mTechnetium, encapsulate it in liposomes and investigate its absorption and tissue distribution after oral administration in mice. Ovalbumin was labeled with 99mTechnetium and encapsulated in small unilamellar vesicles. 99mTc-OVA encapsulated or not in liposomes was administrated to mice that were sacrificed after different times. The radioactivity was measured in various organs of the animals. Differences concerning the biodistribution of 99mTc-OVA were noticed. The technique may represent alternatives for the induction of immunization or oral tolerance.
Ordered mesoporous silica carrier system applied in nanobiothecnology
Authors: Sousa Andreza de , Sousa Edésia Martins Barros de
Published: January 2006

Ordered mesoporous materials like SBA15 possess a network of channels and pores of well-defined size in the nanoscale range (2-50 nm). This particular pore architecture makes them suitable candidates for hosting and delivery under appropriate conditions of a variety of molecules of pharmaceutical interest, including radiopharmaceuticals. The characteristics of SBA-15 prepared in different temperatures and the behavior of this system regarding microencapsulation of a model drug were investigated. The calcined samples were formed in 0.2 g disks and were soaked in a solution of atenolol used as a model drug. The modification of the aging temperature provoked changes in the structure of the pores, indicating the presence of microporosity and connections between mesopores. Aging the materials at a higher temperature resulted in no microporosity and this fact influenced the control of the release of the model drug.
Miomas e infertilidade: bases fisiopatológicas e implicações terapêuticas
Authors: Silva Ana Luiza Berwanger da , Seibel Samuar Albano , Capp Edison , Corleta Helena von Eye
Published: January 2006

OBJETIVOS: analisar evidências da literatura médica que avaliam a relação entre miomas uterinos e infertilidade, assim como as vantagens e desvantagens dos diferentes tipos de tratamentos disponíveis. MÉTODOS: foi realizada uma revisão da literatura utilizando os termos (MeSh terms) "miomas", "infertilidade", "tratamento", "miomectomia", "gestação", na base de dados "Pubmed" e na "The Cochrane Library 2003". O período analisado foi de 1989 a 2003. RESULTADOS: apesar de alguns resultados contraditórios, a maioria dos autores relata uma possível relação de causa-conseqüência entre determinados tipos de miomas e distúrbios reprodutivos. Em relação à terapêutica, observa-se claramente que a miomectomia representa a técnica cirúrgica com melhores resultados, não havendo diferença significativa entre as vias de acesso utilizadas, com exceção da miomatose submucosa, situação em que a via histeroscópica é preferida. As opções não-cirúrgicas de tratamento existentes não parecem ter indicação em pacientes inférteis. CONCLUSÕES: a possível associação entre miomas e distúrbios reprodutivos necessita de melhores investigações. O incremento nas taxas de gestação após ressecção cirúrgica de miomas submucosos leva-nos a acreditar que esses tumores tenham papel na etiologia da infertilidade. Em miomas de outras localizações, entretanto, a relação com infertilidade não é tão clara. A miomectomia é o procedimento de escolha para as pacientes que ainda desejam engravidar.
Auto-imagem corporal de adolescentes atendidos em um programa multidisciplinar de assistência ao adolescente obeso
Authors: Ferriani Maria das Graças C. , Dias Taísa Silva , Silva Karine Zendonadi da , Martins Camilla Soccio
Published: January 2006

O presente estudo teve como objetivo conhecer a percepção de adolescentes obesos em relação ao seu corpo quando dispostos diante de um espelho e a sua influência na sua vida social. Foi utilizada a abordagem qualitativa; os dados foram coletados através de entrevistas semi-estruturadas. A coleta de dados ocorreu com 14 adolescentes obesos de ambos os sexos, na faixa etária entre 10 a 13 anos, e que participaram do "Programa Multidisciplinar de Assistência ao Adolescente Obeso" no ano de 2002. A análise dos dados constituiu-se em descobrir os núcleos temáticos contidos nas falas dos adolescentes, identificando-se dois núcleos: "A relação entre o corpo obeso e o espelho"; "As influências na vida social". Concluiu-se que os adolescentes obesos apresentaram sentimentos conflituosos com relação ao seu corpo, manifestando o receio explícito de se olharem no espelho, devido à insatisfação corporal e a rejeição do próprio corpo. Além disso, vivenciaram experiências estigmatizantes que são refletidas de modo negativo nas suas relações sociais.
Estudo da clientela do Programa de Atendimento Odontológico Precoce em um serviço público do município de Cuiabá, Mato Grosso
Authors: Volpato Luiz Evaristo Ricci , Figueiredo Ângelo Falcão de
Published: January 2006

OBJETIVOS: descrever a clientela assistida pelo Programa de Atendimento Odontológico Precoce de uma clínica municipal de Cuiabá, identificando: a) faixa etária da clientela ao iniciar-se no programa; b) uso de mamadeira por faixa etária; c) uso da mamadeira noturna; d) realização de higiene bucal; e e) presença de cárie dental. MÉTODOS: estudo descritivo de corte transversal, utilizando os 934 prontuários das crianças atendidas pelo programa entre 1996 e 1998. RESULTADOS: 92,93% da clientela do programa era composta por crianças que iniciaram o tratamento com idade entre 0 e 36 meses; até os 42 meses de idade, em apenas uma faixa etária o número de crianças que usavam mamadeira é inferior ao número de crianças que não faziam uso da mesma; entre as crianças que usamvam mamadeira, a maioria absoluta o fazia durante a noite; a realização de higiene bucal e a prevalência da cárie dentária foram diretamente relacionadas à idade da criança. CONCLUSÕES: é necessário um trabalho de conscientização da população quanto à saúde bucal visto que a clientela do serviço estudado apresentou alto índice de desmame precoce e a higiene bucal esteve presente no primeiro ano de vida em apenas um terço das crianças assistidas.
Mulheres de Camaragibe: representação social sobre a vulnerabilidade feminina em tempos de AIDS
Authors: Nascimento Ana Maria Guedes do , Barbosa Constança Simões , Medrado Benedito
Published: January 2006

OBJETIVOS: compreender a representação social que mulheres casadas, em situação de pobreza, possuem acerca da AIDS. Dessa forma, se espera contribuir para que o enfrentamento da epidemia se dê de forma mais sintonizada com a realidade em que essa acontece. MÉTODOS: foram realizadas 16 entrevistas, com mulheres em situação de pobreza, com relação conjugal estável. Essas entrevistas foram gravadas, transcritas e agrupadas segundo critérios de avaliação e análise. A análise foi feita com base na proposta da hermenêutica, que se refere à leitura das entrelinhas. RESULTADOS: foi observado um aumento da vulnerabilidade feminina frente à infecção pelo HIV/AIDS, baseado na representação social que essas mulheres têm da AIDS, visto que suas percepções acabam por lhes fornecer uma falsa sensação de imunidade, pois elas não se encaixam dentro do perfil que imaginam como sendo de quem apresenta o vírus ou a própria doença. CONCLUSÕES: o perfil epidemiológico atual da AIDS aponta a mulher como alvo da infecção. Isso ocorre principalmente através das relações sexuais, que são ditadas pelas relações de gênero. Para elas a AIDS é um mal distante; se próximo, não lhes pertence, se lhes pertence é legitimado por ser "obra de Deus" ou por ser próprio do papel de esposa.
Estresse e função reprodutiva feminina
Authors: Moreira Simone da Nóbrega Tomaz , Lima Josivan Gomes de , Sousa Maria Bernardete Cordeiro de , Azevedo George Dantas de
Published: January 2006

Este artigo discute a relação do estresse sobre a função reprodutiva, considerando que a infertilidade pode ter causas psicológicas (hipótese da psicogênese) ou pode ser a origem do estresse psicológico. A presença do estresse tem o potencial de ativar o eixo hipotálamo-hipófise-adrenal, o qual, inibe o eixo hipotálamo-hipófise-ovariano, levando à paralisação temporária das menstruações. Esse processo pode resultar em infertilidade transitória para as mulheres. Os autores enfatizam a necessidade de uma abordagem psicológica nos serviços de reprodução, objetivando trabalhar as tensões e frustrações advindas da infertilidade e do seu tratamento.
Effect of conventional TENS on pain and electromyographic activity of masticatory muscles in TMD patients
Authors: Rodrigues Delaine , Siriani Anamaria Oliveira , Bérzin Fausto
Published: January 2006

Temporomandibular disorders (TMD) are characterized by several signs and symptoms, such as pain and changes in the electrical activity of masticatory muscles. Considering that transcutaneous electrical nerve stimulation (TENS) is a resource indicated to promote analgesia, the objective of this study was to evaluate the effect of TENS on pain and electromyographic (EMG) activity of the jaw elevator muscles in TMD patients. This study evaluated 35 female volunteers: 19 TMD patients (mean age = 23.04 ± 3.5) and 16 normal subjects (mean age = 23.3 ± 3.0). Transcutaneous electrical nerve stimulation (conventional mode, 150 Hz) was applied once to each group for 45 minutes. Surface electromyography (gain of 100 times and 1 kHz sampling frequency) and the visual analogue scale (VAS) were applied before and immediately after TENS application. Both VAS data and root mean square (RMS) values were analyzed using Student's t-test. The TMD group, compared to the control group, showed higher EMG activity of the jaw elevator muscles at rest. No difference was observed between the groups regarding maximum voluntary clenching (MVC). In TMD patients, TENS reduced both pain and EMG activity of the anterior portion of the temporal muscle, increasing the activity of the masseter muscles during MVC. It is possible to conclude that a single TENS application is effective in pain reduction. However, it does not act homogeneously on the features of the electric activity of the muscles evaluated.
Effect of instruction and motivation in the use of electric and manual toothbrushes in periodontal patients: a comparative study
Authors: Roscher Tove , Rösing Cassiano Kuchenbecker , Gjermo Per , Merete Aass Anne
Published: January 2006

The aim of the present study was to evaluate the efficacy of manual and electric toothbrushes in plaque control in periodontal patients after proper instructions. Thirty six periodontal patients (mean age of 49 years, 21 females and 15 males) were included and completed the study (100% compliance). A single-blinded, randomized, controlled, cross-over clinical design was adopted, with the patients using during 2 periods of 14 days each the manual and/or electric toothbrush. Four subgroups of 9 individuals were studied: A1 - used manual toothbrush in both experimental periods; A2 - used the manual toothbrush during the first period and the electrical toothbrush during the second period; B1 - used electrical toothbrush during both periods; B2 - used the electrical toothbrush in the first period and the manual one in the second period. Brushing was performed during 14 days and at day 14 and 28 it was performed in the clinic, and timing of brushing was recorded without patients being aware. The Plaque Index (Silness, Löe, 1964) was used. Intra-group comparisons were performed by paired t-test and inter-group comparisons by independent sample t-test, with an alpha level of 0.05. The results showed no difference between the tested brushes neither for plaque nor for timing. However, re-instruction was detected as an important factor, since for all groups the second period, after reinstruction, showed lower plaque scores. It is concluded that professional advice and instruction and re-instruction seem more important in order to obtain good plaque control than the choice of toothbrush in subjects with periodontal disease.
Periodontal conditions of teeth presenting pathologic migration
Authors: Costa Maurício Ribeiro , Silvério Karina Gonzales , Rossa Júnior Carlos , Cirelli Joni Augusto
Published: January 2006

The aim of the present study was to evaluate the periodontal conditions of anterior teeth that presented pathologic migration in patients with chronic periodontitis and to compare periodontal destruction in migrated versus non-migrated teeth. The sample included 32 patients of both sexes (mean age: 46.0 ± 11.6 years) diagnosed with generalized chronic periodontitis and selected on the basis of the presence of pathologic migration in one or more anterior teeth. This migration was classified according to the following categories: facial flaring, diastema, proximal tilting, rotation or extrusion. The periodontal parameters recorded were clinical attachment loss (CAL) and percentage of radiographic bone loss (BL). Mean CAL of 5.50 ± 2.20 mm and mean BL of 41.90 ± 15.40% were found in 115 teeth assessed. The most frequent type of migration was facial flaring (34.80%), followed by diastema (27.00%). Extrusion was hardly observed in the sample (4.30%). However, greater severity of BL and CAL were observed in teeth with this type of migration (59.44% and 8.42 mm, respectively), and in teeth with facial flaring (45.17% of BL and 6.07 mm of CAL). Kruskal-Wallis test indicated that BL presented by teeth with extrusion or facial flaring was greater than that observed in rotated or tilted teeth (p < 0.05), while there was no difference between groups regarding CAL (p = 0.11). It was observed that anterior teeth with pathologic migration presented greater CAL and BL (5.1 mm and 40%) than non-migrated teeth (4.1 and 31%). The study indicated that the most prevalent kind of pathologic migration is facial flaring, which was associated to higher level of bone loss.
Peroxide bleaching agent effects on enamel surface microhardness, roughness and morphology
Authors: Pinto Cristiane Franco , Oliveira Rogério de , Cavalli Vanessa , Giannini Marcelo
Published: January 2006

The aim of this study was to evaluate the surface roughness, microhardness and morphology of human enamel exposed to six bleaching agents (at baseline and post-treatment). Human dental enamel samples were obtained from human third molars and randomly divided into seven groups (n = 11): control, Whiteness Perfect - 10% carbamide peroxide (10% CP), Colgate Platinum - 10% CP, Day White 2Z - 7.5% hydrogen peroxide (7.5% HP), Whiteness Super - 37% CP, Opalescence Quick - 35% CP and Whiteness HP - 35% HP. Bleaching agents were applied according to manufacturers' instructions. The control group remained not treated and stored in artificial saliva. Microhardness testing was performed with a Knoop indentor and surface roughness was analyzed with a profilometer. Morphologic observations were carried out with scanning electron microscopy (SEM). Results were statistically analyzed by two-way analysis of variance and Tukey's test (5%), and revealed a significant decrease in microhardness values and a significant increase in surface roughness post-bleaching. Changes in enamel morphology after bleaching were observed under SEM. It was concluded that bleaching agents can alter the microhardness, roughness and morphology of dental enamel surface.
Evaluation of microleakage in human, bovine and swine enamels
Authors: Abuabara Allan , Santos Alex José Souza dos , Aguiar Flavio Henrique Baggio , Lovadino José Roberto
Published: January 2006

The suitability of bovine and swine teeth has been evaluated when they are used as substitutes for extracted human teeth in varied researches. This study evaluated in vitro the marginal microleakage in human, bovine and swine enamel. Cubic cavities (2 x 2 x 2 mm³) were prepared in enamel blocks from human, swine and bovine teeth. The cavities were filled with composite resin and conventional glass-ionomer cement. All the samples were thermocycled for 1,000 cycles (5 ± 2°C - 55 ± 2°C) and immersed in 2% methylene blue solution for 12 hours. The microleakage was quantified by a spectrophotometric technique. The results were statistically analyzed using ANOVA and Tukey's test. The glass-ionomer cement presented significantly higher leakage means (µg/ml ± SD) than the composite resin for all substrates (0.0695 ± 0.01313 vs. 0.0471 ± 0.0163, p < 0.01). No significant differences were found between bovine and swine enamel (0.0668 ± 0.0246 vs. 0.0674 ± 0.0286); however, both presented statistically higher leakage means than human enamel (0.0407 ± 0.0195, p < 0.01). It was concluded that the microleakage pattern was affected by substrates, and that bovine and swine substrates allow higher marginal leakage than human substrates. The results indicate there should be precaution in the substitution of human substrate in laboratory studies of microleakage.
Relation between speaking space of the /s/ sound and freeway space in dentate and edentate subjects
Authors: Souza Raphael Freitas de , Compagnoni Marco Antonio
Published: January 2006

The purpose of this study is to assess the relation between the speaking space of the /s/ sound and the freeway space in two subject groups. One group had natural dentition (Group I, n = 61) and the other comprised complete denture wearers (Group II, n = 33). The analysis was done by means of a jaw-tracking device (K6-I Diagnostic System, Myotronics Research Inc., Seattle, WA, USA). Freeway space was determined by asking the subjects to occlude from the postural rest position. Speaking space of /s/ was measured during the pronunciation of the word "seis" and comprised the mean distance from the /s/ speaking position to maximal intercuspation. A weak correlation was found between the speaking space of /s/ and the freeway space in Group I (r = 0.41, p < 0.01), but in Group II, the correlation was stronger (r = 0.75, p < 0.01). The speaking space of /s/ and freeway space were different in Group I, but statistically similar in Group II (paired t-test, a = 0.05). It can be suggested that anatomic changes following prosthetic procedures caused a functional adaptation which resulted in more similar values for the speaking space of /s/ and the freeway space.
CT-based analysis of malignant tumor volume and localization: a preliminary study
Authors: Cavalcanti Marcelo Gusmão Paraiso , Santos Denise Takehana dos , Perrella Andreia , Vannier Michael Walter
Published: January 2006

The purpose of this study was to correlate 3D-CT (3D computed tomography) volume measurements of malignant tumors with the response to treatment, and to observe bone invasion in these lesions applying a specific imaging protocol. We analyzed 17 individuals with maxillofacial malignant lesions who were submitted to spiral CT (2D-CT). The original data were transferred to an independent workstation using a 3D volume rendering package software, which was used by two examiners to obtain area and volume measurements of the lesions, independently, three times each, prior to and after treatment. The segmentation protocol was applied for the assessment of bone involvement. The difference between imaging and gold standard values was not considered significant (p > 0.05). Regarding bone invasion, three false-negatives were obtained using MPR-CT (multiplanar reconstruction) and no false-negatives were obtained using the 3D segmentation protocol. The use of 3D-CT may be a differential and important factor for expanding options regarding the localization, dimension, and clarification of lesion components.
Feeding-Facilitating Techniques for the Nursing Infant with Robin Sequence
Authors: Nassar Edamil , Marques Ilza Lazarinni , Trindade Alceu Sergio , Bettiol Heloísa
Published: January 2006

Objective

To determine the effectiveness of feeding-facilitating techniques in children with Robin sequence.

Setting

Hospital de Reabilitação de Anomalias Craniofaciais, University of São Paulo, Bauru, São Paulo, Brazil.

Patients

Twenty-six children less than 2 months of age with Robin sequence, whose only cause of respiratory obstruction was glossoptosis. Thirteen infants were treated by being placed in the prone position (Group 1), and 13 were treated by nasopharyngeal intubation (Group 2).

Interventions

During hospitalization, the following feeding-facilitating techniques were applied daily to all children: pacifier, massage to relax and anteriorize the tongue, long and soft bottle nipple with original or enlarged hole, global symmetric position, rhythmic movement of the nipple during suction, and insertion of the nipple on the tongue.

Results

During the first evaluation, Group 1 patients accepted 36.15 ± 33.05 mL milk orally within a period of 44.62 ± 42.94 minutes, whereas Group 2 ingested 20.00 ± 20.51 mL milk within 30.38 ± 25.77 minutes. A significant increase (p < .01) in the volume of ingested milk was observed for the two groups at hospital discharge after a mean treatment period of 10.7 days (Group 1: 63.46 ± 22.58 mL and Group 2: 55.00 ± 13.07 mL). The mean duration of feeding decreased in the two groups, with a value of 21.54 ± 7.18 minutes for Group 1 and of 20.28 ± 8.53 minutes for Group 2.

Conclusion

The results showed that feeding-facilitating techniques can foster oral feeding in infants with Robin sequence.
Facilitating Cleft Palate Team Participation of Culturally Diverse Families in South Africa
Authors: Louw Brenda , Shibambu Mary , Roemer Karin
Published: January 2006

Objective

The Facial Cleft Deformities Clinic, University of Pretoria, Pretoria, South Africa, provides interdisciplinary team services to patients with cleft lip and palate and craniofacial anomalies. They represent the “rainbow nation” of South Africa and reflect the multicultural and multilingual nature of the population, which poses a challenge to effective and accountable service delivery. The aim of this study was to explore some cultural variations that exist in black families that influence their participation in the team approach and to describe the assets of families that may be used to empower them and to enhance service delivery.

Design

A descriptive survey research design. A questionnaire-by-interview procedure was utilized during routine visits of 35 black families to the Facial Cleft Deformities Clinic.

Results

The results are discussed from an ethnographic perspective of the family and describe the knowledge base of the participants, the diagnosis and treatment of the children's cleft lip and palate, family structure and support systems, family income and education, and the geographical distribution of the participants. Implications for building family partnerships and for improving professionals’ cultural competence in order to improve the quality of service delivery are presented.

Conclusions

By viewing cultural differences on a continuum, following the asset-based approach, applying knowledge based on contextually relevant research, and recognizing family uniqueness, families may be empowered to participate fully in the team approach to support their children with cleft lip and palate and craniofacial anomalies in attaining their full potential in the South African context.
The Dynamics in Implantation for Patients with Clefts
Authors: Nagasao Tomohisa , Miyamoto Junpei , Jin Hongmei , Tamaki Tamotsu , Isshiki Yasushige , Kaneko Tsuyoshi , Nakajima Tatsuo
Published: January 2006

Objective

To investigate the stresses and strains of an endosseous dental implant in patients with different types of cleft palate in a finite element model.

Materials and Methods

Seven three-dimensional (3D) maxillary models were designed on a personal computer according to computed tomography slice data obtained from seven dry skulls. Next, computer-aided modification was performed on each model to produce three other 3D models with different cleft patterns. Thus, four model types with different cleft patterns were designed and termed NORM (without cleft), ALVEOLAR (only alveolar cleft), PALATAL (only palatal cleft), and COMPLETE (complete cleft). An implant was embedded into the molar region of each model, and a 300-N vertical load and 50-N horizontal load were applied to simulate mastication. Under these conditions, the stresses occurring at the implant-bone interface were calculated by finite element analysis.

Results

Different stress patterns were observed between the models with a palatal cleft (PALATAL and COMPLETE) and those without palatal cleft (NORM and ALVEOLAR). Regarding vertical load application, greater stresses occurred in PALATAL and COMPLETE types than in NORM and ALVEOLAR types. On application of a horizontal load, though the stresses did not show quantitative difference, their vector patterns differed.

Conclusion

In patients with palatal clefts, characteristic stress patterns occur on the bone-implant interface during mastication. This should be taken into consideration when performing an implant treatment in patients with clefts.
Comparison of Resonance Outcomes after Pharyngeal Flap and Furlow Double-Opposing Z-Plasty for Surgical Management of Velopharyngeal Incompetence
Authors: Dailey Scott A. , Karnell Michael P. , Karnell Lucy Hynds , Canady John W.
Published: January 2006

Objective

The purpose of this study was to test the hypothesis that no significant difference exists in the speech outcomes between patients with severe velopharyngeal incompetence (VPI) who receive a pharyngeal flap and patients with less severe VPI who receive a Z-plasty for management of VPI.

Design

This retrospective study from 1993 to 2002 included a review of pre- and postoperative perceptual speech and resonance assessments of patients with marginal VPI who received a Furlow double-opposing Z-plasty and patients with VPI who received a pharyngeal flap.

Setting

All patients had surgical management of VPI at the Cleft Palate– Craniofacial Clinic at University of Iowa Hospitals and Clinics.

Results

Both groups benefited from surgery with significant reduction in perceived hypernasality (p < .001). Comparison of postoperative assessments indicated no difference between the groups in hypernasality or hyponasality ratings. Neither group had a significant increase in hyponasality.

Conclusion

Both pharyngeal flap and double-opposing Z-plasty proved equally effective at reducing hypernasality when the selection of the surgical procedures was based on preoperative ratings of perceived hypernasality and evaluation of velopharyngeal physiology. Severity of the VPI is an important factor when considering surgical management of VPI. Thorough preoperative evaluations of patients with VPI are essential in appropriate treatment planning.
Contributions of PTCH Gene Variants to Isolated Cleft Lip and Palate
Authors: Mansilla M. A. , Cooper M. E. , Goldstein T. , Castilla E. E. , Camelo J. S. Lopez , Marazita M. L. , Murray J. C.
Published: January 2006

Objective

Mutations in patched (PTCH) cause the nevoid basal cell carcinoma syndrome (NBCCS), or Gorlin syndrome. Nevoid basal cell carcinoma syndrome may present with developmental anomalies, including rib and craniofacial abnormalities, and predisposes to several tumor types, including basal cell carcinoma and medulloblastoma. Cleft palate is found in 4% of individuals with nevoid basal cell carcinoma syndrome. Because there might be specific sequence alterations in PTCH that limit expression to orofacial clefting, a genetic study of PTCH was undertaken in cases with cleft lip and/or palate (CL/P) known not to have nevoid basal cell carcinoma syndrome.

Results

Seven new normal variants spread along the entire gene and three missense mutations were found among cases with cleft lip and/or palate. One of these variants (P295S) was not found in any of 1188 control samples. A second variant was found in a case and also in 1 of 1119 controls. The third missense (S827G) was found in 5 of 1369 cases and in 5 of 1104 controls and is likely a rare normal variant. Linkage and linkage desequilibrium also was assessed using normal variants in and adjacent to the PTCH gene in 220 families (1776 individuals), each with two or more individuals with isolated clefting. Although no statistically significant evidence of linkage (multipoint HLOD peak = 2.36) was uncovered, there was borderline evidence of significant transmission distortion for one haplotype of two single nucleotide polymorphisms located within the PTCH gene (p = .08).

Conclusion

Missense mutations in PTCH may be rare causes of isolated cleft lip and/or palate. An as yet unidentified variant near PTCH may act as a modifier of cleft lip and/or palate.
Impact of Soil Texture on the Distribution of Soil Organic Matter in Physical and Chemical Fractions
Authors: Plante Alain F. , Conant Richard T. , Stewart Catherine E. , Paustian Keith , Six Johan
Published: January 2006

Previous research on the protection of soil organic C from decomposition suggests that soil texture affects soil C stocks. However, different pools of soil organic matter (SOM) might be differently related to soil texture. Our objective was to examine how soil texture differentially alters the distribution of organic C within physically and chemically defined pools of unprotected and protected SOM. We collected samples from two soil texture gradients where other variables influencing soil organic C content were held constant. One texture gradient (16–60% clay) was located near Stewart Valley, Saskatchewan, Canada and the other (25–50% clay) near Cygnet, OH. Soils were physically fractionated into coarse‐ and fine‐particulate organic matter (POM), silt‐ and clay‐sized particles within microaggregates, and easily dispersed silt‐ and clay‐sized particles outside of microaggregates. Whole‐soil organic C concentration was positively related to silt plus clay content at both sites. We found no relationship between soil texture and unprotected C (coarse‐ and fine‐POM C). Biochemically protected C (nonhydrolyzable C) increased with increasing clay content in whole‐soil samples, but the proportion of nonhydrolyzable C within silt‐ and clay‐sized fractions was unchanged. As the amount of silt or clay increased, the amount of C stabilized within easily dispersed and microaggregate‐associated silt or clay fractions decreased. Our results suggest that for a given level of C inputs, the relationship between mineral surface area and soil organic matter varies with soil texture for physically and biochemically protected C fractions. Because soil texture acts directly and indirectly on various protection mechanisms, it may not be a universal predictor of whole‐soil C content.
Selenite Adsorption Mechanisms on Pure and Coated Montmorillonite: An EXAFS and XANES Spectroscopic Study
Authors: Peak Derek , Saha U. K. , Huang P. M.
Published: January 2006

Selenite (SeO32−) is an oxyanion of environmental importance due to its toxicity to animals at higher concentrations, notably waterfowl and grazing animals. Sorption of SeO32− with mineral phases typically controls the movement and bioaccessibility of SeO32− in soils and sediments. Previous studies have successfully utilized synchrotron‐based Extended X‐ray Absorption Fine Structure (EXAFS) and X‐ray Absorption Near Edge Structure (XANES) spectroscopy to determine SeO32− bonding mechanisms on Fe and Mn oxides, but the direct evidence of SeO32− surface complexation mechanisms on important mineral phases such as Al hydroxide and aluminosilicate minerals is still lacking. In this study both EXAFS and XANES spectroscopy was conducted on aqueous SeO32− solutions and on a variety of Al‐bearing sorption samples at pH 4.5. The sorbents chosen were a hydroxyaluminosilicate (HAS) polymer, a hydroxyaluminum (HYA) polymer, montmorillonite, and both HYA and HAS coated montmorillonite. For SeO32− sorption on montmorillonite, only bidentate binuclear inner‐sphere complexation was observed. For the hydroxyaluminum and hydroxyaluminosilicate polymers, a mixture of outer‐sphere and bidentate binuclear inner‐sphere was observed. When montmorillonite was coated with either HYA or HAS polymers then adsorption behavior was intermediate between that of the mineral and the pure polymer. Since temperate soils often contain aluminum‐hydroxy and aluminosilicate coated minerals rather than discrete Al hydroxide minerals and pristine clay surfaces, the adsorption mechanisms observed on these coated surfaces are more realistic of the natural environment than sorption on pure minerals.
Nitrogen Fertilization and Cropping System Impacts on Soil Quality in Midwestern Mollisols
Authors: Russell A. E. , Laird D. A. , Mallarino A. P.
Published: January 2006

High grain production of corn (Zea mays L.) can be maintained by adding inorganic N fertilizer, and also by using crop rotations that include alfalfa (Medicago sativa L.), but the relative impact of these management practices on soil quality is uncertain. We examined the effects on soil of N fertilization rate (0, 90, 180, 270 kg ha−1, corn phase only) in four cropping systems: CC, continuous corn; CS, corn–soybean [Glycine max (L.) Merr.]; CCOA, corn–corn–oat (Avena sativa L.)–alfalfa; and corn–oat–alfalfa–alfalfa (COAA). The 23‐ and 48‐yr‐old experimental sites, situated in northeast (Nashua) and north central (Kanawha) Iowa, were in a replicated split‐plot design and managed with conventional tillage. At Nashua, we measured available N, potential net N mineralization and microbial biomass C (MBC) throughout the growing season; all were significantly higher in the CCOA system. At both sites, post‐harvest N stocks, and soil organic C (SOC) concentrations were significantly higher in systems containing alfalfa. Grain yield was most strongly correlated with soil N properties. At Nashua, N fertilizer additions resulted in significantly lower soil pH (0‐ to 15‐cm depth) and lower exchangeable Ca, Mg, and K and cation exchange capacity (CEC) in the CC and CCOA systems. In an undisturbed prairie reference site for Nashua, low available N, low pH, and high CEC suggested a strong influence of the vegetation on nutrient cycling. In terms of management of soil fertility, inclusion of alfalfa in the rotation differed fundamentally from addition of N fertilizer because high yield was maintained with fewer adverse effects on soil quality.
Modeling the Effects of Fertilizer Application Rate on Nitrous Oxide Emissions
Authors: Grant R. F. , Pattey E. , Goddard T. W. , Kryzanowski L. M. , Puurveen H.
Published: January 2006

The attribution of N2O emission factors to N inputs from chemical fertilizers requires an understanding of how those inputs affect the biological processes from which these emissions are generated. We propose a detailed model of soil N transformations as part of the ecosystem model ecosys for use in attributing N2O emission factors to fertilizer use. In this model, the key biological processes—mineralization, immobilization, nitrification, denitrification, root, and mycorrhizal uptake—controlling the generation of N2O were coupled with the key physical processes—convection, diffusion, volatilization, dissolution—controlling the transport of the gaseous reactants and products of these biological processes. Physical processes controlling gaseous transport and solubility caused large temporal variation in the generation and emission of N2O in the model. This variation limited the suitability of discontinuous surface flux chambers measurements used to test modeled N2O emissions. Continuous flux measurements using micrometeorological techniques were better suited to the temporal scales at which variation in N2O emission occurred and at which model testing needed to be conducted. In a temperate, humid climate, modeled N2O emissions rose nonlinearly with fertilizer application rate once this rate exceeded the crop and soil uptake capacities for added N. These capacities were partly determined by history of fertilizer use, so that the relationship between N2O emissions and current N inputs depended on earlier N inputs. A scheme is proposed in which N2O emission factors rise nonlinearly with fertilizer N inputs that exceed crop plus soil N uptake capacities.