RESUMO
Magnetic fields are fundamental to the evolution of galaxies, playing a key role in the astrophysics of the interstellar medium and star formation. Large-scale ordered magnetic fields have been mapped in the Milky Way and nearby galaxies1,2, but it is not known how early in the Universe such structures formed3. Here we report the detection of linearly polarized thermal emission from dust grains in a strongly lensed, intrinsically luminous galaxy that is forming stars at a rate more than 1,000 times that of the Milky Way at redshift 2.6, within 2.5 Gyr of the Big Bang4,5. The polarized emission arises from the alignment of dust grains with the local magnetic field6,7. The median polarization fraction is of the order of 1%, similar to nearby spiral galaxies8. Our observations support the presence of a 5-kiloparsec-scale ordered magnetic field with a strength of around 500 µG or lower, oriented parallel to the molecular gas disk. This confirms that such structures can be rapidly formed in galaxies, early in cosmic history.
RESUMO
PURPOSE: Aortic metabolic activity is suggested to correlate with presence and progression of aneurysmal disease, but has been inadequately studied. This study investigates the 2-[(18)F] fluoro-2-deoxy-D-glucose ((18)F-FDG) uptake in a population of infra-renal abdominal aortic aneurysms (AAA), compared to a matched non-aneurysmal control group. METHODS: The Positron Emission Tomography - Computed Tomography (PET/CT) database was searched for infra-renal AAA. Exclusion criteria were prior repair, vasculitis, and saccular/mycotic thoracic or thoraco-abdominal aneurysms. Matching of 159 non-aneurysmal (<3 cm diameter) controls from the same population was assessed. Infra-renal aortic wall FDG uptake was assessed using visual analysis; maximum standardized uptake value (SUVmax) and target to background mediastinal blood pool ratio (TBR) were documented. Predictors of FDG uptake (age, sex, aortic diameter, hypertension, statin use, and diabetes) were assessed using univariate analysis. Follow-up questionnaires were sent to referring clinicians. RESULTS: Aneurysms (n = 151) and controls (n = 159) were matched (p > 0.05) for age, sex, diabetes, hypertension, smoking status, statin use, and indication for PET/CT. Median aneurysm diameter was 5.0 cm (range 3.2-10.4). On visual analysis there was no significant difference in the overall numbers with increased visual uptake 24% (36/151) in the aneurysm group vs. 19% (30/159) in the controls, p = ns. SUVmax was slightly lower in the aneurysm group vs. controls (mean (2 SD) 1.75(0.79) vs. 1.84(0.58), p = 0.02). However there was no difference in TBR between the AAA group and controls (mean (2 SD) 1.03 (0.46) vs. 1.05(0.31), p = 0.36). During a median 18 (interquartile range 8-35) months' follow-up 20 were repaired and four were confirmed ruptured. CONCLUSIONS: The level of metabolic activity as assessed by (18)F-FDG PET/CT in infra-renal AAA does not correlate with aortic size and does not differ between aneurysms and matched controls.
Assuntos
Aneurisma da Aorta Abdominal/diagnóstico por imagem , Fluordesoxiglucose F18 , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Imagem Multimodal , Tomografia Computadorizada por Raios XRESUMO
BACKGROUND: Multicentre trials are required to determine how [fluorine-18]-2-fluoro-2-deoxy-D-glucose-positron emission tomography imaging can guide cancer treatment. Consistency in quality control (QC), scan acquisition and reporting is mandatory for high-quality results, which are comparable across sites. METHODS: A national positron emission tomography (PET) clinical trials network (CTN) has been set up with a 'core laboratory' to coordinate QC and interpret scans. The CTN is involved in trials in Hodgkin's lymphoma [Randomised Phase III trial to determine the role of FDG-PET Imaging in Clinical Stages IA/IIA Hodgkin's Disease (RAPID) and Randomised Phase III trial to assess response adapted therapy using FDG-PET imaging in patients with newly diagnosed, advanced Hodgkin lymphoma (RATHL)] and diffuse large B-cell lymphoma [Blinded evaluation of prognostic value of FDG-PET after 2 cycles of chemotherapy in diffuse large B-cell Non-Hodgkins Lymphoma, a sub-study of the R-CHOP-21 vs R-CHOP-14 trial (R-CHOP PET substudy)]. Approval to join requires scanner validation and agreement to follow a standard QC protocol. Scans are transferred to the core laboratory and reported centrally according to predetermined criteria. RESULTS: The qualification procedure was carried out on 15 scanners. All scanners were able to demonstrate the necessary quantitative accuracy, and following modification of image reconstruction where necessary, scanners demonstrated comparable recovery coefficients (RCs) indicating similar performance. The average RC (±1 standard deviation) was 0.56 ± 0.095 for the 13-mm sphere. Reports from 444 of 473 (94%) patients in RAPID and 67 of 73 (92%) patients in RATHL were available for randomisation of therapy. CONCLUSIONS: The CTN has enabled consistent quality assured PET results to be obtained from multiple centres in time for clinical decision making. The results of trials will be significantly strengthened by this system.
Assuntos
Fluordesoxiglucose F18 , Doença de Hodgkin/diagnóstico por imagem , Estudos Multicêntricos como Assunto , Tomografia por Emissão de Pósitrons/normas , Compostos Radiofarmacêuticos , Ensaios Clínicos Controlados Aleatórios como Assunto , Humanos , Controle de Qualidade , Projetos de Pesquisa , Reino UnidoRESUMO
We report a case of regression of pulmonary and bony metastases in a patient with malignant melanoma following palliative treatment with systemic zoledronate and localised radiotherapy to the bone. Zoledronate is a potent new bisphosphonate used for the treatment of metabolic bone diseases including bone metastases due to its inhibitory effect on osteoclasts. In the context of metastatic cancer zoledronate is routinely used to improve bone pain and reduce the frequency of skeletal events. There is also an increasing body of evidence suggesting that bisphosphonates exhibit anti-tumour properties. Bisphosphonates are able to activate Vgamma9Vdelta2 gamma-delta T cells which can be key players in the immune defence against malignant cells. Furthermore bisphosphonates have direct anti-proliferative, anti-metastatic and pro-apoptotic effects on tumour cells. These actions, together with their low side effect profile, may prove to be useful therapeutic tools in the treatment of cancer even in the absence of bone metastases. On the basis of this case report we here review the current literature on present preclinical and clinical studies using bisphosphonates for the treatment of cancer.
Assuntos
Neoplasias Ósseas/tratamento farmacológico , Difosfonatos/uso terapêutico , Imidazóis/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Melanoma/tratamento farmacológico , Apoptose , Neoplasias Ósseas/radioterapia , Neoplasias Ósseas/secundário , Feminino , Humanos , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/secundário , Melanoma/patologia , Melanoma/radioterapia , Pessoa de Meia-Idade , Linfócitos T/imunologia , Linfócitos T/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF/imunologia , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Ácido ZoledrônicoRESUMO
In a prior study of epilepsy and atmospheric pressure, we were able to show a small association between changes in atmospheric pressure and increased seizure frequency in consecutive patients with epilepsy undergoing video telemetry. In this study, we used a larger data set of similar patients undergoing telemetry at another Seattle institution, and examined the possible impact of atmospheric pressure (AP) changes on seizure onset in subtypes of seizures (focal, generalized, and nonepileptic). Comparisons were made between AP score at time of seizure onset and AP score at selected time ranges prior to the event (hour of seizure and 3, 6, and 24 hours prior) and a random sample of AP scores collected over similar time frames using nonparametric testing with correction for multiple comparisons. We could find no evidence to suggest atmospheric pressure changes made seizure occurrence more likely in any of the seizure groups across any of the time periods.
Assuntos
Pressão Atmosférica , Epilepsia/epidemiologia , Convulsões/epidemiologia , Eletroencefalografia , Epilepsia/fisiopatologia , Humanos , Estudos Retrospectivos , Convulsões/classificação , Telemetria , Washington/epidemiologia , Tempo (Meteorologia)RESUMO
A common cause of morbidity and mortality in diabetic patients are foot infection/complications often leading to amputation of lower extremities. Various radiological and radionuclide techniques are available for the assessment of diabetic patients with bone or soft tissue infections. However, there are several advantages and limitations. The major limitation of all these techniques is their inability to accurately differentiate osteomyelitis from charcot's/neuropathic joints. Radiologically, magnetic resonance imaging (MRI) is the technique of choice and a radiolobeled white cell scan is a useful nuclear medicine technique in the evaluation of diabetic patients with suspected foot infection. In this review we discuss the efficacy of radiological and radionuclide techniques in the assessment of diabetic foot infection.
Assuntos
Doenças Ósseas/diagnóstico por imagem , Complicações do Diabetes/diagnóstico por imagem , Pé Diabético/diagnóstico por imagem , Doenças Ósseas/etiologia , Osso e Ossos/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Radiografia , Compostos Radiofarmacêuticos , Tomografia Computadorizada de Emissão de Fóton ÚnicoRESUMO
OBJECTIVE: The aim of this study was to measure the internal dose received by family members from ingestion of radioactive contamination after outpatient therapy. MATERIALS AND METHODS: Advice was given to minimise transfer of radioiodine. Home visits were made approximately 2, 7 and 21 days after treatment to measure radioactivity in the thyroids of family members. A decay correction was applied to radioactivity detected assuming ingestion had occurred at the earlier contact time, either the day of treatment or the previous home visit. An effective half-life of 6 or 7 days was used depending on age. Thyroid activity was summed if activity was found at more than one visit in excess of the amount attributable to radioactive decay. Effective dose (ED) was calculated using ICRP72. RESULTS AND DISCUSSION: Fifty-three adults and 92 children, median age 12 (range 4-17) years participated. Median administered activity was 576 (range 329-690) MBq (131)I. Thyroid activity ranged from 0 to 5.4 kBq in the adults with activity detected in 17. Maximum adult ED was 0.4 mSv. Thyroid activity ranged from 0 to 11.8 kBq in the children with activity detected in 26. The two highest values of 5.0 and 11.8 kBq occurred in children aged 5 and 14 years from different families. Eighty-five children had no activity or <1 kBq detected. ED was <0.2 mSv in 86 out of 92 children (93%). Previous published data showed 93% of children received an ED Assuntos
Exposição Ambiental
, Família
, Hipertireoidismo/radioterapia
, Radioisótopos do Iodo/uso terapêutico
, Pacientes Ambulatoriais
, Doses de Radiação
, Adolescente
, Adulto
, Fatores Etários
, Idoso
, Idoso de 80 Anos ou mais
, Criança
, Pré-Escolar
, Feminino
, Seguimentos
, Educação em Saúde
, Humanos
, Masculino
, Pessoa de Meia-Idade
, Radioatividade
, Glândula Tireoide/efeitos da radiação
Assuntos
Sobrecarga de Ferro , Ferro , Exposição Ocupacional/efeitos adversos , Soldagem , Idoso , Alanina Transaminase/sangue , Biópsia , Humanos , Ferro/sangue , Ferro/toxicidade , Sobrecarga de Ferro/sangue , Sobrecarga de Ferro/induzido quimicamente , Sobrecarga de Ferro/patologia , Fígado/metabolismo , Fígado/patologia , Pulmão/metabolismo , Pulmão/patologia , MasculinoRESUMO
Neuroendocrine tumours (NETs) are a rare type of tumour that can range from well differentiated slow growing tumours to poorly differentiated aggressive tumours. NETs can arise in different parts of the body. Patients often present with a large spectrum of clinical syndromes, which depend on the presence of hormones secreted by the tumour type or by a mass effect. Several imaging modalities are used in the diagnosis of NETs. Radionuclide imaging plays an important role in diagnosis, staging and treatment of these tumours. Several radiopharmaceuticals are used to image NETs and are based on different cellular uptake mechanisms. This review will focus on the functional imaging of NETs using single photon emission computed tomography and positron emission tomography radiopharmaceuticals.
Assuntos
Tumores Neuroendócrinos/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada de Emissão de Fóton Único , Humanos , Tumores Neuroendócrinos/diagnóstico , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos , Sensibilidade e Especificidade , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Tomografia Computadorizada por Raios XRESUMO
AIM: To evaluate the "state of art" of clinical role of sentinel lymph node (SLN) biopsy procedure in patients affected by differentiated thyroid carcinoma. METHODS: All papers cited on PubMed/MEDLINE until June 2005, published in English, and referred to the key words "sentinel lymph node biopsy" AND "thyroid carcinoma" OR "thyroid cancer" were reviewed for the purpose of the present study. RESULTS: The first method used for SLN biopsy in thyroid carcinoma patients was the vital blue dye technique. This technique had some disadvantages as: (a) risk of disruption of the lymphatic channels deriving from the thyroid cancer; (b) difficulty in disclosing SLN lying outside the central compartment; (c) parathyroid glands can take up blue dye and, thus, can be misinterpreted as lymph nodes. Some of the above cited disadvantages were overcome by using the lymphoscintigraphy and intraoperative gamma probe technique. A combination of the blue dye and gamma probe technique has also been proposed with synergic results. CONCLUSION: The reported advantages of the SLN biopsy in small differentiated thyroid carcinoma patients can be resumed as follows: (a) better selection of patients who would benefit from compartment oriented nodal dissection; (b) more accurate lymph node staging; (c) better selection of patients who can require (131)I treatment after surgery (SLN positive for metastasis); (d) better identification of SLN located out of the central compartment.
Assuntos
Metástase Linfática/diagnóstico , Biópsia de Linfonodo Sentinela , Neoplasias da Glândula Tireoide/patologia , Corantes , Humanos , Metástase Linfática/diagnóstico por imagem , Metástase Linfática/patologia , Esvaziamento Cervical , CintilografiaRESUMO
BACKGROUND: Previous studies have shown that pericytes can differentiate into osteoblasts and form bone. This study investigated whether pericytes can also differentiate into chondrocytes and adipocytes. METHODS AND RESULTS: Reverse transcription-polymerase chain reaction demonstrated that pericytes express mRNA for the chondrocyte markers Sox9, aggrecan, and type II collagen. Furthermore, when cultured at high density in the presence of a defined chondrogenic medium, pericytes formed well-defined pellets comprising cells embedded in an extracellular matrix rich in sulfated proteoglycans and type II collagen. In contrast, when endothelial cells were cultured under the same conditions, the pellets disintegrated after 48 hours. In the presence of adipogenic medium, pericytes but not endothelial cells expressed mRNA for peroxisome proliferator-activated receptor-gamma2 (an adipocyte-specific transcription factor) and incorporated lipid droplets that stained with oil red O. To confirm that pericytes can differentiate along the chondrocytic and adipocytic lineages in vivo, these cells were inoculated into diffusion chambers and implanted into athymic mice for 56 days. Accordingly, mineralized cartilage, fibrocartilage, and a nonmineralized cartilaginous matrix with lacunae containing chondrocytes were observed within these chambers. Small clusters of cells that morphologically resembled adipocytes were also identified. CONCLUSIONS: These data demonstrate that pericytes are multipotent cells that may contribute to growth, wound healing, repair, and/or the development and progression of various pathological states.
Assuntos
Adipócitos/citologia , Condrócitos/citologia , Pericitos/citologia , Adipócitos/metabolismo , Agrecanas , Animais , Biomarcadores , Cartilagem/citologia , Bovinos , Diferenciação Celular , Células Cultivadas/citologia , Células Cultivadas/metabolismo , Condrócitos/metabolismo , Colágeno Tipo II/biossíntese , Colágeno Tipo II/genética , Cultura em Câmaras de Difusão , Matriz Extracelular/metabolismo , Proteínas da Matriz Extracelular/biossíntese , Proteínas da Matriz Extracelular/genética , Perfilação da Expressão Gênica , Proteínas de Grupo de Alta Mobilidade/biossíntese , Proteínas de Grupo de Alta Mobilidade/genética , Lectinas Tipo C , Camundongos , Camundongos Nus , PPAR gama/biossíntese , PPAR gama/genética , Pericitos/metabolismo , Proteoglicanas/biossíntese , Proteoglicanas/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição SOX9 , Fatores de Transcrição/biossíntese , Fatores de Transcrição/genéticaRESUMO
Derivatives of plasmid pBR322 DNA containing tet mutations were constructed by inserting XhoI linkers at various sites in the tetracycline resistance gene. Monomer plasmids containing either the tet-10 allele located at nucleotide position 23 or the tet-14 allele located at nucleotide position 1267 were used to construct a circular dimer containing one copy of each allele and a circular trimer containing one copy of the tet-10 allele and two copies of the tet-14 allele. Genetic recombination of these plasmid DNAs to produce a functional tetracycline resistance gene could be detected as the production of tetracycline-resistant progeny during the growth of transformants or using a restriction mapping assay which detected the rearrangement of the mutant alleles. The structure of individual tetracycline-resistant recombination products was determined by restriction mapping. This analysis suggested that as many as 70% of the plasmid recombination events in Escherichia coli AB1157 could have involved gene conversion events. The formation of these recombination products was most easily predicted by a model involving figure 8 recombination intermediates and the formation of symmetric regions of heteroduplex. Recombination in JC10287 delta(srlR-recA)304 occurred at 5% of the wild-type frequency and appeared to occur by a similar mechanism. Recombination in JC9604 recA56 recB21 recC22 sbcA23 occurred at 20 times the wild-type frequency and appeared to involve multiple independent recombination events.
Assuntos
DNA Bacteriano/genética , Escherichia coli/genética , Plasmídeos , Recombinação Genética , Enzimas de Restrição do DNA , Resistência Microbiana a Medicamentos , Eletroforese em Gel de Ágar , Conversão Gênica , Genes Bacterianos , Mutação , Ácidos Nucleicos Heteroduplexes/genética , TetraciclinaRESUMO
At postconfluence, cultured bovine pericytes isolated from retinal capillaries form three-dimensional nodule-like structures that mineralize. Using a combination of Northern and Southern blotting, in situ hybridization, and immunofluorescence we have demonstrated that this process is associated with the stage-specific expression of markers of primitive clonogenic marrow stromal cells (STRO-1) and markers of cells of the osteoblast lineage (bone sialoprotein, osteocalcin, osteonectin, and osteopontin). To demonstrate that the formation of nodules and the expression of these proteins were indicative of true osteogenic potential, vascular pericytes were also inoculated into diffusion chambers and implanted into athymic mice. When recovered from the host, chambers containing pericytes were found reproducibly to contain a tissue comprised of cartilage and bone, as well as soft fibrous connective tissue and cells resembling adipocytes. This is the first study to provide direct evidence of the osteogenic potential of microvascular pericytes in vivo. Our results are also consistent with the possibility that the pericyte population in situ serves as a reservoir of primitive precursor cells capable of giving rise to cells of multiple lineages including osteoblasts, chondrocytes, adipocytes, and fibroblasts.
Assuntos
Osteoblastos/citologia , Osteogênese/fisiologia , Vasos Retinianos/citologia , Animais , Antígenos de Diferenciação/metabolismo , Capilares/citologia , Bovinos , Diferenciação Celular , Divisão Celular , Células Cultivadas , Cultura em Câmaras de Difusão , Humanos , Técnicas In Vitro , Sialoproteína de Ligação à Integrina , Camundongos , Osteoblastos/imunologia , Osteoblastos/metabolismo , Osteocalcina/genética , Osteonectina/genética , Osteopontina , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Sialoglicoproteínas/genética , Células-Tronco/citologia , Células-Tronco/imunologia , Células-Tronco/metabolismo , Células Estromais/citologia , Células Estromais/imunologia , Células Estromais/metabolismoRESUMO
Pericytes, an integral part of the microvasculature, are involved in a number of different processes, including angiogenesis. Many of the early studies on these cells are descriptive and concentrate on the location of pericytes in vivo, surrounding the endothelial cells in the microvessels. These studies led to the proposals that pericytes have a function in maintaining blood flow and contribute to the mechanical strength of the microvessels. However, with the advancement of tissue culture techniques and molecular technology it has been shown that these cells also have the ability to differentiate into a variety of different cell types, including osteoblasts, chondrocytes, adipocytes, fibroblasts, and smooth muscle cells. This review concentrates on the differentiation of pericytes along the osteogenic pathway. Pericytes behave like osteoblasts in vitro, by forming a mineralized matrix and expressing a number of genes that are also expressed by osteoblasts. These cells also form a well-defined matrix of bone, cartilage, and fibrous tissue in vivo, although it is not clear under what circumstances pericytes express osteogenic potential in situ. This review highlights the potential functional importance of pericytes in the growth, maintenance, and repair of the skeleton and in diseases involving ectopic ossification and calcification.
Assuntos
Diferenciação Celular/genética , Endotélio Vascular/metabolismo , Regulação da Expressão Gênica/genética , Pericitos/fisiologia , Animais , Divisão Celular , Condrócitos/metabolismo , Microcirculação/citologia , Osteoblastos/metabolismo , Pericitos/metabolismo , FagocitoseRESUMO
A full-length cDNA encoding a novel human protein phosphatase 1 (PP1) binding subunit of molecular mass 36 kDa, termed PPP1R5, was sequenced. PPP1R5 shows 42% identity to the glycogen binding subunit (G(L)) of PP1 from rat liver and 28% identity to the N-terminal region of the glycogen binding subunit (G(M)) of PP1 from human skeletal muscle. Like G(L), PPP1R5 modulates the specificity of PP1, but it differs from G(L) in being present in a wide variety of tissues, besides liver. The amino acid sequence and properties of PPP1R5 indicate that it is not subject to the same modes of covalent and allosteric regulation by hormones as are G(M) and G(L).
Assuntos
Glicogênio/metabolismo , Fígado/metabolismo , Músculos/metabolismo , Fosfoproteínas Fosfatases/química , Fosfoproteínas Fosfatases/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Proteínas de Transporte , DNA Complementar , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Dados de Sequência Molecular , Testes de Precipitina , Proteína Fosfatase 1 , Ratos , Homologia de Sequência de AminoácidosRESUMO
A full-length cDNA encoding the putative hepatic glycogen-binding (GL) subunit of protein phosphatase-1 (PP1) was isolated from a rat liver library. The deduced amino acid sequence (284 residues, 32.6 kDa) was 23% identical (39% similar) to the N-terminal region of the glycogen-binding (GM) subunit of PP1 from striated muscle. The similarities between GM and GL were most striking between residues 63-86, 144-166 and 186-227 of human GM (approximately 40% identity), nearly all the identities with the putative yeast homologue GAC1 being located between 144-166 and 186-227. The cDNA was expressed in E. coli, and the expressed protein transformed the properties of PP1 to those characteristic of the hepatic glycogen-associated enzyme. These experiments establish that the cloned protein is GL.
Assuntos
Proteínas de Transporte/biossíntese , Glicogênio Hepático/metabolismo , Fígado/enzimologia , Músculo Esquelético/enzimologia , Fosfoproteínas Fosfatases/biossíntese , Sequência de Aminoácidos , Animais , Sequência de Bases , Sítios de Ligação , Proteínas de Transporte/química , Proteínas de Transporte/metabolismo , Clonagem Molecular , Primers do DNA , Biblioteca Gênica , Glutationa Transferase/biossíntese , Humanos , Cinética , Substâncias Macromoleculares , Dados de Sequência Molecular , Fases de Leitura Aberta , Especificidade de Órgãos , Fosfoproteínas Fosfatases/química , Fosfoproteínas Fosfatases/metabolismo , Fosforilase a/metabolismo , Reação em Cadeia da Polimerase , Proteína Fosfatase 1 , Coelhos , Ratos , Proteínas Recombinantes de Fusão/metabolismo , Homologia de Sequência de AminoácidosRESUMO
PCR-based subtractive hybridisation was used to identify genes up-regulated when pericytes undergo osteogenic differentiation and deposit a calcified matrix. cDNA pools were generated from confluent pericytes and from pericyte cultures containing calcified nodules. A pericyte cDNA library was screened with the product of the subtraction procedure (calcified minus confluent cDNA) and the majority of the positive clones were identified as matrix Gla protein (MGP). Northern analysis and immunohistochemistry demonstrated that MGP was only expressed by pericytes in calcified nodules. Antibodies to MGP inhibited the deposition of a calcified matrix by pericytes, suggesting that MGP regulates both cell differentiation and calcification.
Assuntos
Calcificação Fisiológica , Proteínas de Ligação ao Cálcio/genética , Proteínas da Matriz Extracelular , Pericitos/fisiologia , Sequência de Aminoácidos , Animais , Anticorpos , Proteínas de Ligação ao Cálcio/análise , Proteínas de Ligação ao Cálcio/metabolismo , Bovinos , Diferenciação Celular , Células Cultivadas , Biblioteca Gênica , Dados de Sequência Molecular , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/imunologia , Pericitos/citologia , Vasos Retinianos/citologia , Vasos Retinianos/fisiologia , Proteína de Matriz GlaRESUMO
Diffusion-weighted imaging (DWI) can help to diagnose acute ischemic stroke. Other nonischemic disorders may show abnormal signals with DWI. The authors report two cases of Wernicke encephalopathy with DWI signal changes in characteristic midline locations, one with reduction in apparent diffusion constant and one without. DWI abnormalities may suggest early thiamine deficiency and are useful in diagnosing Wernicke encephalopathy.
Assuntos
Encefalopatia de Wernicke/diagnóstico , Adulto , Alcoolismo/complicações , Alcoolismo/patologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Deficiência de Tiamina/complicações , Deficiência de Tiamina/diagnóstico , Tomografia Computadorizada por Raios X , Encefalopatia de Wernicke/etiologiaRESUMO
Automatisms are commonly seen in epilepsy, either ictally or postictally. However, most automatisms are simple, with hand movements, mouth smacking, nose-rubbing, repetition of a single word, or coughing, grunting, or screeching. Complex automatisms are less common and striking. The authors report two cases of seizure-associated singing where song expression may be recognizable.
Assuntos
Automatismo/etiologia , Epilepsia Parcial Complexa/fisiopatologia , Epilepsia Generalizada/fisiopatologia , Música , Adulto , Automatismo/fisiopatologia , Eletroencefalografia , Epilepsia Parcial Complexa/diagnóstico , Epilepsia Generalizada/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , VozRESUMO
In order to assess the ability of six potential bone graft substitutes to support the growth of human osteoblasts, these cells were grown in culture and then plated onto fragments of the six materials and cultured for a further period of 15 days. Tests to confirm the osteoblastic phenotype of the cells included spectrophotometric alkaline phosphatase assay; Western blotting of secreted osteocalcin, osteonectin, bone sialoprotein, and collagen type I; and mineralization within the cultures provided with a supplemented medium. Cells were seeded onto the materials in 24-well plates (Nunc, Naperville, IL) at density levels 12,500 cells/cm2 and 25,000 cells/cm2. Specimens were examined after the 15-day culture period by scanning electron microscopy. At a seeding density of 12,500 cells/cm2 results showed that the human osteoblasts had greatest affinities for demineralized rat bone and demineralized Surgibone, whilst few osteoblasts were found attached to Pyrost, Surgibone, or coral. The collagen matrix of Callopat hydrated in the culture media exposing the hydroxyapatite crystals within it, and these became the foci for cell attachment and growth. At a seeding density of 25,000 cells/cm2 the osteoblasts had attached to and proliferated upon the surfaces of all the materials, forming multilayers, with the exception of Surgibone. These experiments demonstrated that all the materials, with the exception of nondemineralized Surgibone, were biocompatible for human osteoblasts.(ABSTRACT TRUNCATED AT 250 WORDS)