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1.
J Robot Surg ; 17(6): 2749-2756, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37707742

RESUMO

Robotic navigation has been shown to increase precision, accuracy, and safety during spinal reconstructive procedures. There is a paucity of literature describing the best techniques for robotic-assisted spine surgery for complex, multilevel cases or in cases of significant deformity correction. We present a case series of 100 consecutive multilevel posterior spinal fusion procedures performed for multilevel spinal disease and/or deformity correction. 100 consecutive posterior spinal fusions were performed for multilevel disease and/or deformity correction utilizing robotic-assisted placement of pedicle screws. The primary outcome was surgery-related failure, which was defined as hardware breakage or reoperation with removal of hardware. A total of 100 consecutive patients met inclusion criteria. Among cases included, 31 were revision surgeries with existing hardware in place. The mean number of levels fused was 5.6, the mean operative time was 303 min, and the mean estimated blood loss was 469 mL. 28 cases included robotic-assisted placement of S2 alar-iliac (S2AI) screws. In total, 1043 pedicle screws and 53 S2AI screws were placed with robotic-assistance. The failure rate using survivorship analysis was 18/1043 (1.7%) and the failure rate of S2AI screws using survivorship analysis was 3/53 (5.7%). Four patients developed postoperative wound infections requiring irrigation and debridement procedures. None of the 1043 pedicle screws nor the 53 S2AI screws required reoperation due to malpositioning or suboptimal placement. This case series of 100 multilevel posterior spinal fusion procedures demonstrates promising results with low failure rates. With 1043 pedicle screws and 53 S2AI screws, we report low failure rates of 1.7% and 5.7%, respectively with zero cases of screw malpositioning. Robotic screw placement allows for accurate screw placement with no increased rate of postoperative infection compared to historical controls. Level of evidence: IV, Retrospective review.


Assuntos
Parafusos Pediculares , Procedimentos Cirúrgicos Robóticos , Robótica , Fusão Vertebral , Humanos , Procedimentos Cirúrgicos Robóticos/métodos , Fusão Vertebral/métodos , Coluna Vertebral , Estudos Retrospectivos
2.
Orthopedics ; 46(5): 310-314, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36853948

RESUMO

Deep infection is a debilitating complication after shoulder arthroplasty. The authors hypothesized that an intra-articular, intraoperative injection of antibiotics would result in a lower infection rate compared with intravenous antibiotics alone. Before 2007, 164 patients (group A) did not receive intra-articular antibiotics. From 2007 to 2018, 1324 patients (group B) received intra-articular antibiotics. Patients received intra-articular gentamicin at the end of surgery with the addition of 1 g of cefazolin in January 2014. Records were retrospectively reviewed for comorbidities, type of surgery, and infection. The cohort that received intra-articular antibiotics was compared with the cohort that did not to determine the effect of prophylactic intra-articular antibiotic administration in preventing infection. There was 1 deep infection in the antibiotic group compared with 5 in the non-antibiotic group (P<.001). Superficial infections developed in 2 cases of patients treated with antibiotics; there were no superficial infections in patients treated without antibiotics (P=.62). One previous study evaluated intra-articular injection of antibiotics for shoulder arthroplasty and found significantly lower rates of infection with the injection of intra-articular gentamicin. In this retrospective follow-up study, the injection of intra-articular gentamicin or gentamicin and cefazolin effectively decreased rates of postoperative infection. At mean follow-up of 399 days, intra-articular antibiotics at the time of surgery resulted in significantly fewer deep infections. Given the minimal risk of adverse events and minimal cost, this is a valid method of reducing infections in total shoulder arthroplasty. [Orthopedics. 2023;46(5):310-314.].


Assuntos
Artroplastia do Ombro , Infecções Relacionadas à Prótese , Humanos , Antibacterianos/uso terapêutico , Cefazolina/uso terapêutico , Estudos Retrospectivos , Seguimentos , Artroplastia do Ombro/efeitos adversos , Injeções Intra-Articulares , Gentamicinas/uso terapêutico , Infecções Relacionadas à Prótese/etiologia , Infecções Relacionadas à Prótese/prevenção & controle , Infecções Relacionadas à Prótese/tratamento farmacológico
3.
J Dent Res ; 99(10): 1157-1164, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32392084

RESUMO

Public health policy decisions in the United States have resulted in 62.4% of the population having access to fluoridated water. The purpose of this study was to examine the association between community water fluoridation and osteosarcoma. A secondary data analysis was performed with data collected from 2 separate but linked studies. Patients for phase 1 and phase 2 were selected from US hospitals via a matched case-control study design. For both phases, cases included patients diagnosed with osteosarcoma, and controls were patients diagnosed with other bone tumors or nonneoplastic conditions. In phase 1, cases (n = 209) and controls (n = 440) were patients of record in the participating orthopedic departments from 1989 to 1993. In phase 2, cases (n = 108) and controls (n = 296) were incident patients who were identified and treated by orthopedic physicians from 1994 to 2000. This analysis included all patients who met eligibility criteria on whom we had complete data on covariates, exposures, and outcome. Conditional logistic regression was used to estimate odds ratios (ORs) and 95% CIs for the association of community water fluoridation with osteosarcoma. A modestly significant interaction existed between fluoridation living status and bottled water use (P = 0.047). The adjusted OR for osteosarcoma and ever having lived in a fluoridated area for nonbottled water drinkers was 0.51 (95% CI, 0.31 to 0.84; P = 0.008). In the same comparison, the adjusted OR for bottled water drinkers was 1.86 (95% CI, 0.54 to 6.41; P = 0.326). Findings from this study demonstrated that community water fluoridation is not associated with an increased risk for osteosarcoma.


Assuntos
Neoplasias Ósseas , Fluoretação , Osteossarcoma , Adolescente , Adulto , Neoplasias Ósseas/epidemiologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Razão de Chances , Osteossarcoma/epidemiologia , Osteossarcoma/etiologia , Estados Unidos/epidemiologia , Abastecimento de Água , Adulto Jovem
4.
Clin Cancer Res ; 24(9): 2116-2127, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29476017

RESUMO

Purpose: Cancer-initiating cells (C-IC) have been described in multiple cancer types, including colorectal cancer. C-ICs are defined by their capacity to self-renew, thereby driving tumor growth. C-ICs were initially thought to be static entities; however, recent studies have determined these cells to be dynamic and influenced by microenvironmental cues such as hypoxia. If hypoxia drives the formation of C-ICs, then therapeutic targeting of hypoxia could represent a novel means to target C-ICs.Experimental Design: Patient-derived colorectal cancer xenografts were treated with evofosfamide, a hypoxia-activated prodrug (HAP), in combination with 5-fluorouracil (5-FU) or chemoradiotherapy (5-FU and radiation; CRT). Treatment groups included both concurrent and sequential dosing regimens. Effects on the colorectal cancer-initiating cell (CC-IC) fraction were assessed by serial passage in vivo limiting dilution assays. FAZA-PET imaging was utilized as a noninvasive method to assess intratumoral hypoxia.Results: Hypoxia was sufficient to drive the formation of CC-ICs and colorectal cancer cells surviving conventional therapy were more hypoxic and C-IC-like. Using a novel approach to combination therapy, we show that sequential treatment with 5-FU or CRT followed by evofosfamide not only inhibits tumor growth of xenografts compared with 5-FU or CRT alone, but also significantly decreases the CC-IC fraction. Furthermore, noninvasive FAZA-PET hypoxia imaging was predictive of a tumor's response to evofosfamide.Conclusions: Our data demonstrate a novel means to target the CC-IC fraction by adding a HAP sequentially after conventional adjuvant therapy, as well as the use of FAZA-PET as a biomarker for hypoxia to identify tumors that will benefit most from this approach. Clin Cancer Res; 24(9); 2116-27. ©2018 AACR.


Assuntos
Neoplasias Colorretais/metabolismo , Hipóxia/metabolismo , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Nitroimidazóis/administração & dosagem , Mostardas de Fosforamida/administração & dosagem , Pró-Fármacos/administração & dosagem , Animais , Biomarcadores , Caspases/metabolismo , Hipóxia Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Quimiorradioterapia , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Neoplasias Colorretais/radioterapia , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Sinergismo Farmacológico , Feminino , Humanos , Masculino , Camundongos , Fenótipo , Tomografia por Emissão de Pósitrons , Padrão de Cuidado , Via de Sinalização Wnt , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Contrast Media Mol Imaging ; 2017: 9481276, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29097943

RESUMO

Peptide-receptor imaging and therapy with radiolabeled somatostatin analogs such as 68Ga-DOTA-TATE and 177Lu-DOTA-TATE have become an effective treatment option for SSTR-positive neuroendocrine tumors. The purpose of this study was to evaluate the correlation of somatostatin receptor-2 (SSTR2) expression with 68Ga-DOTA-TATE uptake and 177Lu-DOTA-TATE therapy in neuroblastoma (NB) xenograft models. We demonstrated variable SSTR2 expression profiles in eight NB cell lines. From micro-PET imaging and autoradiography, a higher uptake of 68Ga-DOTA-TATE was observed in SSTR2 high-expressing NB xenografts (CHLA-15) compared to SSTR2 low-expressing NB xenografts (SK-N-BE(2)). Combined autoradiography-immunohistochemistry revealed histological colocalization of SSTR2 and 68Ga-DOTA-TATE uptake in CHLA-15 tumors. With a low dose of 177Lu-DOTA-TATE (20 MBq/animal), tumor growth inhibition was achieved in the CHLA-15 high SSTR2 expressing xenograft model. Although, in vitro, NB cells showed variable expression levels of norepinephrine transporter (NET), a molecular target for 131I-MIBG therapy, low 123I-MIBG uptake was observed in all selected NB xenografts. In conclusion, SSTR2 expression levels are associated with 68Ga-DOTA-TATE uptake and antitumor efficacy of 177Lu-DOTA-TATE. 68Ga-DOTA-TATE PET is superior to 123I-MIBG SPECT imaging in detecting NB tumors in our model. Radiolabeled DOTA-TATE can be used as an agent for NB tumor imaging to potentially discriminate tumors eligible for 177Lu-DOTA-TATE therapy.


Assuntos
Radioisótopos de Gálio/farmacocinética , Neuroblastoma/diagnóstico por imagem , Receptores de Somatostatina/análise , Animais , Linhagem Celular Tumoral , Quelantes , Radioisótopos de Gálio/uso terapêutico , Compostos Heterocíclicos com 1 Anel , Xenoenxertos , Humanos , Lutécio/uso terapêutico , Camundongos , Neuroblastoma/radioterapia , Tomografia por Emissão de Pósitrons/métodos , Radioisótopos/uso terapêutico , Compostos Radiofarmacêuticos/farmacocinética , Receptores de Somatostatina/metabolismo
6.
N Z Vet J ; 64(4): 253-6, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26850500

RESUMO

CASE HISTORY: A 14-year-old neutered male Sealyham terrier was referred for assessment of a persistent pyoderma. It had experienced numerous episodes of dermatitis involving pododermatitis, pyoderma and otitis over the previous 6 years. CLINICAL FINDINGS: Superficial, focally deep and mucocutaneous pyoderma were present, with yellow mucoid exudate on both nares and the lower lips crusted with haemopurulent exudate. Epidermal collarettes were present on the dorsal and lateral trunk. There were peri-anal crusts and mild erythema was present on the concave aspect of both pinnae. MICROBIOLOGICAL FINDINGS: Culture and microbiological testing identified Staphylococcus pseudintermedius as the infecting organism. Kirby-Bauer disc susceptibility testing revealed the isolate was resistant to numerous antimicrobials including oxacillin. PCR testing of the isolate identified the presence of the mecA gene which confers resistance to ß-lactam antimicrobials. Pulsed field gel electrophoresis typing suggested the isolate was not related to the methicillin-resistant S. pseudintermedius that had been reported to be associated with canine infections in Western Australia. DIAGNOSIS: Superficial, deep and mucus membrane pyoderma associated with a multi-drug resistant S. pseudintermedius. CLINICAL RELEVANCE: This is the first recorded case of canine pyoderma involving methicillin-resistant multidrug-resistant S. pseudintermedius in New Zealand. Treatment of such cases is difficult because the number of effective and available antimicrobials is limited. This finding should raise the awareness of the veterinary and medical professions to the presence of such organisms in New Zealand and stimulate a discussion about possible biosecurity barriers, treatment strategies and prevention of zoonotic and nosocomial infections.


Assuntos
Proteínas de Bactérias/metabolismo , Doenças do Cão/microbiologia , Farmacorresistência Bacteriana Múltipla , Infecções Cutâneas Estafilocócicas/veterinária , Staphylococcus/efeitos dos fármacos , Animais , Proteínas de Bactérias/genética , Doenças do Cão/epidemiologia , Cães , Masculino , Nova Zelândia/epidemiologia , Infecções Cutâneas Estafilocócicas/epidemiologia , Infecções Cutâneas Estafilocócicas/microbiologia , Staphylococcus/classificação
7.
J Nucl Med ; 57(3): 361-6, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26769863

RESUMO

UNLABELLED: Pancreatic cancers are thought to be unusually hypoxic, which might sensitize them to drugs that are activated under hypoxic conditions. In order to develop this idea in the clinic, a minimally invasive technique for measuring the oxygenation status of pancreatic cancers is needed. METHODS: We tested the potential for minimally invasive imaging of hypoxia in pancreatic cancer patients, using the 2-nitroimidazole PET tracer (18)F-fluoroazomycin arabinoside (or (18)F-1-α-D-[5-fluoro-5-deoxyarabinofuranosyl]-2-nitroimidazole [(18)F-FAZA]). Dynamic and static scans were obtained in 21 patients with either locally advanced or metastatic disease. The hypoxic fraction was determined in the 2-h static scans as the percentage of voxels with SUVs more than 3 SDs from the mean values obtained for skeletal muscle. RESULTS: Hypoxia was detected in 15 of 20 evaluable patients, with the hypoxic fraction ranging from less than 5% to greater than 50%. Compartmental analysis of the dynamic scans allowed us to approximate the tumor perfusion as mL/min/g of tissue, a value that is independent of the extent of hypoxia derived from tracer uptake in the 2-h static scan. There was no significant correlation between tumor perfusion and hypoxia; nor did we see an association between tumor volume and hypoxia. CONCLUSION: Although pancreatic cancers can be highly hypoxic, a substantial proportion appears to be well oxygenated. Therefore, we suggest that a minimally invasive technique such as the one described in this study be used for patient stratification in future clinical trials of hypoxia-targeting agents.


Assuntos
Hipóxia/diagnóstico por imagem , Nitroimidazóis/farmacocinética , Neoplasias Pancreáticas/diagnóstico por imagem , Compostos Radiofarmacêuticos/farmacocinética , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Feminino , Humanos , Hipóxia/etiologia , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Metástase Neoplásica/diagnóstico por imagem , Neoplasias Pancreáticas/irrigação sanguínea , Neoplasias Pancreáticas/complicações , Tomografia por Emissão de Pósitrons , Fluxo Sanguíneo Regional
8.
J Thorac Oncol ; 11(2): 213-21, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26718880

RESUMO

INTRODUCTION: Treatment of locally advanced non-small cell lung cancer with chemoradiotherapy (CRT) is limited by development of toxicity in normal tissue, including radiation esophagitis (RE). Increasingly, (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET) is being used for adaptive planning. Our aim was to assess changes in esophageal FDG uptake during CRT and relate the changes to the onset and severity of RE. METHODS: This prospective study in patients with stage II-III non-small cell lung cancer involved serial four-dimensional computed tomography and PET scans during CRT (60-74Gy). RE was recorded weekly using the Common Terminology Criteria for Adverse Events (v4.0), and imaging was performed at weeks 0, 2, 4, and 7. Changes in the esophagus's peak standard uptake value (SUVpeak) were analyzed for each time point and correlated with grade of RE using the Wilcoxon rank-sum test. The volume of esophagus receiving 50 Gy (V50) and volume of esophagus receiving 60 Gy (V60) were correlated with the development of RE, and the C-statistic (area under the curve [AUC]) was calculated to measure predictivity of grade 3 RE. RESULTS: RE developed in 20 of 27 patients (74%), with grade 3 reached in 6 (22%). A significant percentage increase in SUVpeak in the patients with RE was noted at week 4 (p = 0.01) and week 7 (p = 0.03). For grade 3 RE, a significant percentage increase in SUVpeak was noted at week 2 (p = 0.01) and week 7 (p = 0.03) compared with that for less than grade 3 RE. Median V50 (46.3%) and V60 (33.4%) were significantly higher in patients with RE (p = 0.04). The AUC measurements suggested that the percentage change in SUVpeak at week 2 (AUC = 0.69) and V50 (AUC = 0.67) and V60 (AUC = 0.66) were similarly predictive of grade 3 RE. CONCLUSIONS: Serial FDG-PET images during CRT show significant increases in SUVpeak for patients in whom RE develops. The changes at week 2 may predict those at risk for the development of grade 3 RE and may be informative for adaptive planning and early intervention.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/terapia , Quimiorradioterapia/efeitos adversos , Esofagite/etiologia , Fluordesoxiglucose F18 , Neoplasias Pulmonares/terapia , Tomografia por Emissão de Pósitrons , Lesões por Radiação/etiologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
9.
Plant Genome ; 8(1): eplantgenome2014.09.0051, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33228284

RESUMO

Chenopodium L. is a relatively under-studied genus that includes the cultivated seed crop quinoa (C. quinoa Willd.). Quinoa is an allotetraploid (2n = 4x = 36, AABB genomes) that is cultivated by subsistence farmers and commercial growers in the Andean regions of South America. Approximately 60% of a quinoa seed is starch, a glucose polymer that is an important carbohydrate energy source in the human diet. Seed starch is normally composed of amylose and amylopectin in a 1:3 ratio. The accumulation of the amylose fraction of starch is controlled by a single dominant gene in quinoa, GBSSI. We report the sequencing and characterization of the GBSSI gene in 18 accessions of Chenopodium, including Andean quinoa and the related Mesoamerican chenopod domesticate, C. berlandieri subsp. nuttalliae Saff. Two distinct homeologs (GBSSIa and GBSSIb) were identified in the tetraploid accessions, and 19 different alleles were identified, including three null mutants-one in an accession of quinoa and two in a waxy landrace of C. berlandieri subsp. nuttalliae. Expression analysis of the null mutants revealed that GBSSIa and GBSSIb were both strongly expressed late in seed development. GBSSI sequences were used to analyze the phylogenetic relationships between quinoa and other members of the Chenopodium genus. This study and the discovery of Chenopodium GBSSI null-mutants will assist in the development of new Chenopodium crops with novel starches.

10.
J Cereb Blood Flow Metab ; 34(1): 108-17, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24064494

RESUMO

Patients with aneurysmal subarachnoid hemorrhage (SAH) frequently have deficits in learning and memory that may or may not be associated with detectable brain lesions. We examined mediators of long-term potentiation after SAH in rats to determine what processes might be involved. There was a reduction in synapses in the dendritic layer of the CA1 region on transmission electron microscopy as well as reduced colocalization of microtubule-associated protein 2 (MAP2) and synaptophysin. Immunohistochemistry showed reduced staining for GluR1 and calmodulin kinase 2 and increased staining for GluR2. Myelin basic protein staining was decreased as well. There was no detectable neuronal injury by Fluoro-Jade B, TUNEL, or activated caspase-3 staining. Vasospasm of the large arteries of the circle of Willis was mild to moderate in severity. Nitric oxide was increased and superoxide anion radical was decreased in hippocampal tissue. Cerebral blood flow, measured by magnetic resonance imaging, and cerebral glucose metabolism, measured by positron emission tomography, were no different in SAH compared with control groups. The results suggest that the etiology of loss of LTP after SAH is not cerebral ischemia but may be mediated by effects of subarachnoid blood such as oxidative stress and inflammation.


Assuntos
Região CA1 Hipocampal/ultraestrutura , Hemorragia Subaracnóidea/patologia , Animais , Região CA1 Hipocampal/metabolismo , Região CA1 Hipocampal/fisiopatologia , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Modelos Animais de Doenças , Potenciação de Longa Duração/fisiologia , Imageamento por Ressonância Magnética , Masculino , Microscopia Eletrônica de Transmissão , Proteínas Associadas aos Microtúbulos/metabolismo , Proteína Básica da Mielina/metabolismo , Ratos , Ratos Endogâmicos SHR , Ratos Sprague-Dawley , Receptores de AMPA/metabolismo , Hemorragia Subaracnóidea/metabolismo , Hemorragia Subaracnóidea/fisiopatologia
11.
Cancer Biother Radiopharm ; 28(3): 254-9, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23350894

RESUMO

The present study aims to image the 18-kDa translocator protein (TSPO; formerly known as the peripheral benzodiazepine receptor) in a preclinical human breast cancer (BC) xenograft mouse model with positron-emission tomography (PET). An automated radiosynthesis of [(18)F]-N-(2-(2-fluoroethoxy)benzyl)-N-(4-phenoxypyridin-3-yl)acetamide ([(18)F]FEPPA) was validated for human use using a commercial synthesis module and resulted in a high radiochemical yield (30%±8%, uncorrected; n=54) and specific activity (6±4 Ci/µmol). Tumor uptake of [(18)F]FEPPA in mice bearing subcutaneous MDA-MB-231 BC xenografts was evaluated by PET-computed tomography imaging and ex vivo biodistribution studies. Although the tumor was successfully visualized, ex vivo biodistribution studies revealed low tumor uptake (0.7%ID/g), with the majority of radioactivity distributed in the spleen, muscle, and heart despite high TSPO expression in this cell line. Our laboratory routinely prepares [(18)F]FEPPA for human-imaging studies in the central nervous system, and we envision that radiopharmaceuticals that target the TSPO have the potential for imaging macrophages in the tumor microenvironment.


Assuntos
Anilidas , Neoplasias da Mama/diagnóstico por imagem , Radioisótopos de Flúor , Piridinas , Compostos Radiofarmacêuticos , Receptores de GABA/análise , Anilidas/farmacocinética , Animais , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Feminino , Xenoenxertos , Humanos , Camundongos , Camundongos Nus , Tomografia por Emissão de Pósitrons/métodos , Piridinas/farmacocinética , Compostos Radiofarmacêuticos/farmacocinética , Receptores de GABA/metabolismo
12.
J Nucl Med Technol ; 39(4): 264-70, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21969354

RESUMO

UNLABELLED: Quantitative small-animal PET of mice requires successful delivery of radiotracers into the venous system. Intravenous injection of radiotracers via lateral tail veins is the most commonly used method of administration and can be technically challenging. Evaluation of the quality of an intravenous injection is necessary to determine whether small-animal PET is quantitatively accurate. The purpose of this study was to evaluate and compare the quality of 50 consecutive intravenous injections into mouse tail veins using both quantitative and qualitative methods. METHODS: During (18)F-FDG intravenous injection, qualitative assessment of the injection was performed and classified according to specific criteria as good, intermediate, or poor. Small-animal PET scans of the body and tail were acquired, and tail injection sites were quantitatively assessed in terms of percentage injected dose per gram and classified as low, medium, or high uptake of (18)F-FDG. Qualitative and quantitative methods were compared. To assess baseline amounts of (18)F-FDG in the tail without a tail injection, 3 additional mice were injected by the intraperitoneal method, imaged, and quantitatively assessed in the same manner. The in vivo imaging data were validated on 7 additional mice by sacrificing them after scans, removing their tails, rescanning the tails, and then measuring the tail radioactivity ex vivo in a γ-counter and correlating it with the in vivo amount. RESULTS: Validation of in vivo imaging to ex vivo data yielded an excellent correlation, with an r(2) value of 0.95. Comparison of qualitative and quantitative methods yielded 45 matching results (42 good and low, 2 intermediate and medium, and 1 poor and high). There were 5 cases of mismatching results (1 false-negative and 4 false-positive) between qualitative and quantitative methods. Low-uptake tail injections were comparable to the intraperitoneal injection values. Using qualitative methods, accuracy was true 90% (45/50) of the time. The overall rate of successful intravenous injections was 92% (46/50) using quantitative methods. CONCLUSION: Qualitative assessment is all that is necessary if the intravenous injection is classified as good. In intermediate, poor, or uncertain classifications, a scan of the tail should be performed for quantitative assessment.


Assuntos
Fluordesoxiglucose F18/administração & dosagem , Tomografia por Emissão de Pósitrons/veterinária , Cauda/irrigação sanguínea , Cauda/diagnóstico por imagem , Imagem Corporal Total/veterinária , Animais , Injeções Intravenosas/veterinária , Camundongos , Compostos Radiofarmacêuticos/administração & dosagem , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
13.
J Dent Res ; 90(10): 1171-6, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21799046

RESUMO

The association between fluoride and risk for osteosarcoma is controversial. The purpose of this study was to determine if bone fluoride levels are higher in individuals with osteosarcoma. Incident cases of osteosarcoma (N = 137) and tumor controls (N = 51) were identified by orthopedic physicians, and segments of tumor-adjacent bone and iliac crest bone were analyzed for fluoride content. Logistic regression adjusted for age and sex and potential confounders of osteosarcoma was used to estimate odds ratios (OR) and 95% confidence intervals (CI). There was no significant difference in bone fluoride levels between cases and controls. The OR adjusted for age, gender, and a history of broken bones was 1.33 (95% CI: 0.56-3.15). No significant association between bone fluoride levels and osteosarcoma risk was detected in our case-control study, based on controls with other tumor diagnoses.


Assuntos
Neoplasias Ósseas/química , Osso e Ossos/química , Fluoretos/análise , Osteossarcoma/química , Adolescente , Adulto , Estudos de Casos e Controles , Criança , Intervalos de Confiança , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Fatores de Risco , Estatísticas não Paramétricas , Inquéritos e Questionários , Adulto Jovem
14.
J Neurol Neurosurg Psychiatry ; 81(6): 646-9, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20522872

RESUMO

BACKGROUND: New criteria for the neurophysiological diagnosis of amyotrophic lateral sclerosis/motor neuron disease (ALS/MND) were recently proposed at an international symposium in Awaji-shima, Japan. They differ from the accepted revised El-Escorial criteria by considering fasciculation potentials to be evidence of acute denervation. In addition, when assessing diagnostic certainty, the Awaji-shima criteria equate electrodiagnostic evidence of lower motor neuron dysfunction with clinical examination findings. METHODS: A retrospective review of 205 consecutive sets of notes was performed, from patients who underwent neurophysiological assessment for suspected MND. The clinical signs and neurophysiological findings were combined according to the two sets of criteria (revised El-Escorial and Awaji-shima), and the diagnoses reached were compared with the interval diagnosis, to establish the sensitivities and specificities of each protocol. RESULTS: An interval diagnosis of MND was recorded in 107 patients. The sensitivity of the Awaji-shima criteria in reaching a diagnosis of MND was 60.7% and the revised El-Escorial 28%, with a specificity of 95.9% for both criteria. The Awaji-shima criteria increased the sensitivity of diagnosis without affecting the specificity. CONCLUSION: Accepting EMG evidence of fasciculations as evidence of acute denervation increases the diagnostic certainty of MND, and the new criteria allow earlier diagnosis of MND without increasing the false-positive rate.


Assuntos
Esclerose Lateral Amiotrófica/diagnóstico , Esclerose Lateral Amiotrófica/fisiopatologia , Eletromiografia/métodos , Inquéritos e Questionários , Adulto , Idoso , Idoso de 80 Anos ou mais , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença dos Neurônios Motores/diagnóstico , Doença dos Neurônios Motores/fisiopatologia , Condução Nervosa/fisiologia
15.
Int J Radiat Oncol Biol Phys ; 76(3): 850-8, 2010 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-19515502

RESUMO

PURPOSE: To quantify, in a feasibility study, metabolic and volumetric response to fractionated radiation therapy (RT) using weekly (18)F fluoro-deoxyglucose positron emission tomography (PET) imaging for 10 non-Hodgkin lymphoma (NHL) patients, and to correlate them to clinical outcome. METHODS AND MATERIALS: Ten patients with chemotherapy-refractory NHL planned for radical RT were prospectively entered into a research study. PET/computed tomography (CT) scans were acquired before RT, and repeated weekly during the 3- to 4-week course of RT, and at 1 and 3 months after therapy. Gross tumor volumes were contoured on CT scans and the corresponding maximum standardized uptake values (SUV(max)) determined in the coregistered PET images. The clinical outcomes of interest were local tumor response at 3 months post-RT and local tumor status at last follow-up or time of death. RESULTS: (18)F fluoro-deoxyglucose uptake from inflammation was rarely observed. The responses showed a large variability between patients. SUV(max) decreased consistently with a median of -2.1% per Gy (range, -3.3 to -0.7) and the median of the volumetric response was -2.2% per Gy (range, -2.8 to +0.5). Initial SUV(max) was not correlated with local control, whereas smaller initial tumor volume was, with smaller tumors more likely to achieve local control. The responses after treatment were also correlated to local control, but not the responses during treatment. CONCLUSIONS: Radiation does not confound the FDG uptake in the NHL tumor and normal tissues. Only smaller initial tumor volume and metabolic and volumetric response after completion of radiation therapy significantly correlated with eventual local control.


Assuntos
Fluordesoxiglucose F18 , Linfoma não Hodgkin/diagnóstico por imagem , Linfoma não Hodgkin/radioterapia , Compostos Radiofarmacêuticos , Fracionamento da Dose de Radiação , Estudos de Viabilidade , Fluordesoxiglucose F18/farmacocinética , Humanos , Linfoma não Hodgkin/metabolismo , Linfoma não Hodgkin/patologia , Tomografia por Emissão de Pósitrons/métodos , Estudos Prospectivos , Compostos Radiofarmacêuticos/farmacocinética , Indução de Remissão , Fatores de Tempo , Tomografia Computadorizada por Raios X/métodos , Carga Tumoral
16.
J Nucl Med ; 50(11): 1848-56, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19837760

RESUMO

UNLABELLED: Breast cancers (BCs) with high human epidermal growth factor receptor type 2 (HER2) expression are most likely to respond to trastuzumab; however, the mechanisms of action of trastuzumab are complex and there are no established biomarkers to accurately monitor treatment outcome in individual patients. Therefore, our aim was to determine, in human BC xenografts in athymic mice treated with trastuzumab, whether there were any changes in (18)F-FDG uptake that were associated with response to the drug and that could have utility in monitoring response in patients. METHODS: Baseline tumor uptake of (18)F-FDG was measured in mice with MDA-MB-361 HER2-overexpressing xenografts and MDA-MB-231 xenografts with low HER2 expression by small-animal PET imaging on day 0. Mice were treated with phosphate-buffered saline (PBS) or trastuzumab (4 mg/kg), and small-animal PET was repeated 2 d after treatment. Maintenance doses of trastuzumab (2 mg/kg) or PBS were administered on days 7 and 14, and mice were imaged again on days 9 and 16. Tumor uptake was measured as percentage injected dose per gram (%ID/g) by volume-of-interest analysis on days 0 (baseline), 2, 9, and 16, followed by biodistribution studies on day 16. Tumor growth was measured, and a tumor growth index was calculated. RESULTS: The treatment of mice with trastuzumab, compared with control mice treated with PBS, resulted in a significant decrease in tumor uptake of (18)F-FDG in HER2-overexpressing MDA-MB-361 xenografts after 16 d of treatment (2.6 +/- 0.8 %ID/g vs. 4.6 +/- 1.8 %ID/g, respectively; P < 0.03) but not after 2 or 9 d of treatment (P = 0.28-0.32). In contrast, there was no significant change in the tumor uptake of MDA-MB-231 xenografts with low HER2 expression during the entire course of therapy (4.4 +/- 1.7 %ID/g vs. 3.6 +/- 1.1 %ID/g, respectively; P = 0.31). Trastuzumab treatment, compared with PBS treatment of controls, resulted in significant growth inhibition of MDA-MB-361 xenografts as early as 10 d from the initiation of treatment (tumor growth index, 0.7 +/- 0.2 vs. 1.7 +/- 0.3, respectively; P < 0.0005), whereas no tumor growth inhibition was observed for MDA-MB-231 xenografts (5.3 +/- 2.7 and 5.2 +/- 3.0; P = 0.95). CONCLUSION: Changes in the tumor uptake of (18)F-FDG after therapy accurately identified responding and nonresponding human BC xenografts in athymic mice treated with trastuzumab; however, diminished glucose utilization did not precede changes in tumor volume.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/terapia , Fluordesoxiglucose F18 , Animais , Anticorpos Monoclonais Humanizados , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Transformação Celular Neoplásica , Feminino , Fluordesoxiglucose F18/farmacocinética , Regulação Neoplásica da Expressão Gênica , Genes erbB-2/genética , Humanos , Imuno-Histoquímica , Camundongos , Camundongos Nus , Tomografia por Emissão de Pósitrons , Sensibilidade e Especificidade , Distribuição Tecidual , Tomografia Computadorizada por Raios X , Trastuzumab , Resultado do Tratamento
17.
Chem Commun (Camb) ; (37): 5527-9, 2009 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-19753345

RESUMO

A novel PET radiotracer, [18F]-1-deoxy-1-fluoro-scyllo-inositol, was synthesized via a one-pot reaction in 16 +/- 3% uncorrected radiochemical yield within 80 minutes; although this compound revealed low brain penetration it shows promise in rodent tumour models for breast cancer imaging.


Assuntos
Inositol/análogos & derivados , Compostos Radiofarmacêuticos/síntese química , Animais , Linhagem Celular Tumoral , Radioisótopos de Flúor/química , Humanos , Inositol/síntese química , Inositol/química , Masculino , Camundongos , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos/química , Ratos , Ratos Sprague-Dawley , Estereoisomerismo , Transplante Heterólogo
18.
Eur J Dent Educ ; 12 Suppl 1: 64-73, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18289269

RESUMO

The ultimate purpose of both dental industry and dental education is to improve the oral health of the public. This report provides background information on the different roles and objectives of the dental industry and dental education communities, the different operating environment of each sector and also areas of common interest where collaboration will be of mutual benefit. The report addresses five areas for potential collaboration between the dental industry and the dental education communities: 1. Contribution to joint activities. 2. Effectiveness and efficiency. 3. Workforce needs. 4. Middle- and low-income countries. 5. The future of International Federation of Dental Educators and Associations (IFDEA). The traditional areas of support and their limitations that have been provided by industry are outlined in the report and some new approaches for collaboration are considered. Industry-based research has been an important factor in developing new products and technologies and in promoting oral health. However there is a need to facilitate the introduction of these developments at an early stage in the education process. Industry has to operate in an efficient manner to remain competitive and maximise its returns and therefore survive. The academic sector operates in a different environment and under different governance structures; although some trends are noted towards adoption of greater efficiency and financial accountability similar to industry. Opportunities to jointly develop best business practices should be explored. Industry has responded well to the oral health needs of the public through the development of new products and technologies. The education community needs to respond in a similar way by examining different healthcare delivery models worldwide and developing programmes to train members of the dental team to cater for future needs and demands of communities in different regions of the world. The reputation of industry-based scientists and clinicians is high, and their role in contributing to the dental education process in practical ways needs to be explored and further developed. Closer relationships between industry scientists and faculty and students could assist industrys need and desire to develop new technologies for the broader dental care system. The corporate sector can play a key role in the future success of IFDEA by providing support and expertise in developing areas such as regional leadership institutes, a Global Faculty and Network and in collaborating in developing continuing education programmes as well as involvement in its governance. Thirteen recommendations are made in the report. These are considered to be important initial steps in developing the already strong relationship between the education and corporate sectors. Partnership and collaborating more effectively along the lines suggested should, almost certainly, generate mutually beneficial outcomes, whilst serving over the long term to elevate the publics oral health status on a global basis.


Assuntos
Comportamento Cooperativo , Educação em Odontologia , Setor de Assistência à Saúde , Relações Interinstitucionais , Saúde Bucal , Atenção à Saúde , Assistência Odontológica , Odontologia , Países em Desenvolvimento , Educação Continuada em Odontologia , Eficiência , Setor de Assistência à Saúde/organização & administração , Promoção da Saúde , Necessidades e Demandas de Serviços de Saúde , Humanos , Disseminação de Informação , Liderança , Setor Privado , Apoio à Pesquisa como Assunto , Sociedades Odontológicas , Tecnologia Odontológica , Apoio ao Desenvolvimento de Recursos Humanos , Recursos Humanos
19.
J Nucl Med Technol ; 35(4): 246-51, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18006594

RESUMO

UNLABELLED: This study evaluated the use of gated versus nongated PET acquisitions for absolute quantification of radioisotope concentration (RC) in a respiratory motion-simulated moving phantom filled with radioactive spheres and background for both 2-dimensional (2D) and 3-dimensional (3D) acquisitions. METHODS: An image-quality phantom with all 6 spheres filled with the same (18)F RC (range, 19-62 kBq/mL) was scanned with PET/CT at rest and in motion with and without gating. The background was filled with (18)F solution to yield sphere-to-background ratios of approximately 5, 10, 15, and 20 to 1. Both 2D and 3D acquisitions were used for all combinations. Respiratory motion was simulated by using a motor-driven plastic platform to move the phantom periodically with a displacement of 2 cm and a cycle time of 5.8 s. For gated acquisitions, the phantom was tracked using a real-time position management system. Images were reconstructed, and regions of interest with the same sizes as the actual spheres were manually placed on axial slices to determine maximum and mean pixel RC. A threshold method (70% and 94% for 2D and 3D modes) was also used to determine a mean voxel RC. All values were compared with the expected RC; percentage differences were calculated for each sphere. To reduce partial-volume effects, only data for the 4 largest spheres were analyzed. RESULTS: The mean pixel method was the only method with linear responses for all 3 scan types, enabling direct comparisons. The ranges of RC percentage differences were underestimated for all scan types (using the mean pixel method). The overall mean percentage differences were 37, 49, and 41 in 2D mode and 40, 51, and 41 in 3D mode for static, nongated, and gated acquisitions, respectively. Gated acquisitions improved quantification (by reducing underestimation) over nongated acquisitions by 8% and 10% for 2D and 3D modes. CONCLUSION: In the presence of motion, the use of gated PET acquisitions appears to improve quantification accuracy over nongated acquisitions, almost restoring the results to those observed when the phantom is static.


Assuntos
Análise de Elementos Finitos , Imagens de Fantasmas/normas , Tomografia por Emissão de Pósitrons/métodos , Técnica de Subtração , Artefatos , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Movimento (Física) , Imagens de Fantasmas/estatística & dados numéricos , Tomografia por Emissão de Pósitrons/normas , Doses de Radiação , Valores de Referência , Reprodutibilidade dos Testes , Respiração , Sensibilidade e Especificidade
20.
Am J Clin Oncol ; 30(2): 113-25, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17414459

RESUMO

OBJECTIVE: The objective of this multicenter phase III trial was to study the impact on time to treatment failure (TTF) and survival of cyclophosphamide, Adriamycin, and 5-fluorouracil (CAF) versus CAF/thiotepa, Adriamycin, vinblastine, and Halotestin (TsAVbH), a partially noncross-resistant regimen used in a rotating schedule in the treatment of hormone insensitive metastatic breast cancer in accordance with the Goldie and Coldman hypothesis. METHODS: Three hundred forty-three patients received 6 cycles of induction treatment with one of 2 regimens. Patients with estrogen receptor-negative tumors or those with estrogen receptor-positive or estrogen receptor-unknown tumors with demonstrated unresponsiveness to hormone treatment were eligible. Complete responders were randomized to either observation or maintenance therapy with cyclophosphamide, methotrexate, 5-fluorouracil, prednisone, tamoxifen, and Halotestin (CMF[P]TH). Patients with partial response or stable disease on completion of induction therapy were maintained on CMF plus Halotestin. RESULTS: There were no differences in the primary end point of TTF (median 7.3 and 7.4 months, respectively). There was a significant difference in TTF and survival by duration of disease-free interval: a median of 8.8 and 21.2 months for those with a disease-free interval of > or =2 years versus 6 to 8 and 13.3 months for those with a disease-free interval <2 years (P = 0.016 and <0.001), respectively. Toxicity of the 2 treatment regimens was similar. CONCLUSION: There were no differences observed in TTF, survival, and toxicities between the 2 treatment arms, both of which contained doxorubicin (Adriamycin) as the most active agent. The results of observation versus maintenance in complete responders were reported separately.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias da Mama/patologia , Ciclofosfamida/administração & dosagem , Doxorrubicina/administração & dosagem , Esquema de Medicação , Feminino , Fluoruracila/administração & dosagem , Humanos , Metástase Neoplásica/tratamento farmacológico , Seleção de Pacientes , Fatores de Tempo , Falha de Tratamento , Resultado do Tratamento
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