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2.
J Clin Microbiol ; 60(4): e0235521, 2022 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-35285727

RESUMO

Varicella-zoster virus (VZV) is the etiologic agent of varicella (chickenpox) and herpes zoster (shingles) infections commonly involving skin, mucous membranes, and less frequently the central nervous system. Traditional methods for the laboratory diagnosis of these infections are time-consuming, labor-intensive, and often insensitive. As such, these tests are being replaced by more sensitive and rapid molecular methods. This study evaluated the performance of two different molecular assays, the Simplexa VZV Direct and Simplexa VZV Swab Direct, to detect VZV DNA in cerebrospinal fluid (CSF) and lesion-swab specimens, respectively. The Simplexa VZV Direct and Simplexa VZV Swab Direct assays were compared against individual composite reference methods that varied depending on the sample cohort examined. A total of 883 CSF and 452 cutaneous and mucocutaneous prospective, retrospective, and contrived specimens were evaluated in this multicenter study. The results of this study showed that the Simplexa assays demonstrated near perfect agreement (k = 0.98) compared to the composite reference methods for the detection of VZV in CSF and lesion swab specimens. A further comparison between the standard of care molecular assays employed at the site of specimen collection and the Simplexa assays demonstrated excellent agreement (k = 1.0). The Simplexa assays offer rapid and reliable alternatives for the detection of VZV in certain clinical specimens without the need for nucleic acid extraction.


Assuntos
Varicela , Herpes Zoster , Varicela/diagnóstico , Herpes Zoster/diagnóstico , Herpesvirus Humano 3/genética , Humanos , Estudos Prospectivos , Estudos Retrospectivos , Manejo de Espécimes
3.
Nurse Educ Today ; 109: 105207, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34801293

RESUMO

BACKGROUND: Interprofessional communication is essential for the coordination and collaboration of healthcare team members during patient care, especially in critical situations. Therefore, nursing students must learn and practice interprofessional communication skills throughout their education and clinical training. Previous studies evaluating standardized communication frameworks in the United States (e.g., ISBARR [identify, situation, background, assessment, recommendation, and repeat]) suggest that nursing students feel more confident about interprofessional communication and collaboration through familiarity with these frameworks. OBJECTIVE: To evaluate the effect of an ISBARR workshop on knowledge of and attitude about effective communication among Chinese undergraduate students. DESIGN: A pre- and posttest quasi-experimental study. PARTICIPANTS: A convenience sample of 90 undergraduate nursing students at a vocational health college in China. METHOD: The two-part ISBARR workshop featured a lecture and a video-simulation exercise. Differences in students' knowledge of and attitudes about interprofessional communication skills using ISBARR were compared pre- and post-workshop. RESULTS: We observed a statistically significant (p < 0.001) improvement in overall mean scores of students' knowledge of and attitudes about utilizing ISBARR post-workshop. We also observed a statistically significant (p < 0.001) improvement in the overall mean scores of students' knowledge of and attitudes about ISBARR after the video-simulation exercise. CONCLUSION: The ISBARR workshop improved Chinese nursing students' knowledge and attitudes about interprofessional communication. Incorporating ISBARR into the nursing healthcare team eventually can lead to improved patient safety. Subsequent studies should target nursing faculty and clinical instructors to evaluate their knowledge and attitudes about teaching ISBARR and interprofessional education. Improving these attitudes can help establish a positive interprofessional communication learning environment for nursing students in China and other cultural contexts worldwide.


Assuntos
Bacharelado em Enfermagem , Estudantes de Enfermagem , Atitude , Atitude do Pessoal de Saúde , Comunicação , Humanos , Relações Interprofissionais , Equipe de Assistência ao Paciente
4.
Am J Health Syst Pharm ; 78(24): 2216-2224, 2021 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-34226914

RESUMO

PURPOSE: The following review is offered as an aid for encouraging deeper understanding by pharmacy graduates of approaches to debt management. SUMMARY: The phenomenon of growing debt for pharmacists and other professionals has been well described. Significant debt is widespread with both pharmacy students and graduates; a recent study described the debt-to-income ratio for pharmacists to have risen by 141% between 2010 and 2016. This increasing debt burden causes significant pressure for these individuals-whether while in training, early in their career, or, increasingly, even in midcareer. Dealing with debt has become a major consideration in the profession. Given that financial education is addressed only minimally, if at all, in pharmacy curricula, pharmacists find it challenging to understand and fully consider the myriad factors influencing the accumulation and repayment of debt in the context of their financial goals. Personal financial, repayment, behavioral, and emotional/psychological factors must be considered to choose an optimal strategy to address debt. This article describes various repayment plans, particularly focusing on those offered with direct loans, and it reviews in some detail 5 comprehensive repayment strategies (using these plans). Three case studies derived from real-life pharmacist-planner interactions illustrate the many factors that must be considered as a pharmacist chooses the optimal approach to debt repayment in their unique life situation. CONCLUSION: Education of students and pharmacists regarding the various factors related to handling student debt may facilitate decision-making that is both financially and personally beneficial.


Assuntos
Currículo , Apoio ao Desenvolvimento de Recursos Humanos , Humanos
5.
Appl Opt ; 59(6): 1602-1610, 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-32225658

RESUMO

A novel, to the best of our knowledge, method of wet chemical etching of sapphire workpieces (such as optics, wafers, windows, and cones), called the sapphire advanced mitigation process (or sapphire AMP), has been developed that exposes sub-surface mechanical damage created during the optical fabrication process and significantly enhances the surface laser damage resistance ($ \gt {2{\times}}$>2×) and mechanical strength (up to $\sim{2.6{\times}}$∼2.6×). Sapphire AMP involves first treating the workpiece with a mixture of sulfuric and phosphoric acid $([{\rm H_{2}{\rm SO_{4}}}]:[{\rm H_{3}{\rm PO_{4}}}]=1:3)$([H2SO4]:[H3PO4]=1:3) at 220°C, followed with phosphoric acid at 160°C, then with sodium hydroxide base (NaOH) and surfactant at 40°C, and finally with a high-pressure deionized water spray rinse. Sapphire AMP has been demonstrated on both A- and C-plane sapphire workpieces. The mechanism of this etch process involves the reaction of the sapphire $({\rm Al_{2}}{\rm O_{3}})$(Al2O3) surface with sulfuric acid $({\rm H_{2}}{\rm SO_{4}})$(H2SO4) forming aluminum sulfate $[{{\rm Al}_2}{({{\rm SO}_4})_3}]$[Al2(SO4)3], which has low solubility. The high phosphoric acid content in the first and second steps of sapphire AMP results in the efficient conversion of ${{\rm Al}_2}{({{\rm SO}_4})_3}$Al2(SO4)3 to aluminum phosphate $({\rm AlPO_{4}})$(AlPO4), which is very soluble, greatly reducing reaction product redeposition on the workpiece surface. Sapphire AMP is shown to expose sub-surface mechanical damage on the sapphire surface created during the grinding and polishing processes, whose etched morphology has either isotropic or anisotropic evolution depending on the nature of the initial surface damage. Sapphire AMP was also designed to remove the key known surface, laser absorbing precursors (namely, foreign chemical impurities, the fracture surface layer of preexisting sub-surface damage, and reaction product or foreign species redeposition or precipitation). Static and sliding indention induced surface microfractures on sapphire are shown after sapphire AMP to have a significant decrease in the fast photoluminescence intensity (a known metric for measuring the degree of laser damaging absorbing precursors). In addition, the onset of laser damage (at 351 nm 3 ns) on sapphire AMP treated workpieces was shown to increase in fluence from $\sim{4}$∼4 to $ \gt {9}.{5}\;{{\rm J/cm}^2}$>9.5J/cm2. Finally, biaxial ball-on-ring mechanical tests on sapphire disks showed an increase in the failure stress from 340 MPa (with pre-existing 28 µm flaws) to $\sim{900}\;{\rm MPa}$∼900MPa after sapphire AMP, which is attributed to the blunting of the surface microfractures.

6.
Theriogenology ; 87: 161-166, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-27658746

RESUMO

Beef Quality Assurance programs have contributed to significant improvements in the wholesomeness of beef available for consumption. Injection site blemishes in the round have declined since the promotion of administering intramuscular injections in the neck. Unfortunately, many producers continue to administer estrus synchronization (ES) drugs in the rump. The objective of this study was to compare the effectiveness of injection site of PGF2α, in ES protocols, on steroid hormone concentrations and pregnancy rates. A Select Synch + 7-day controlled internal drug release ES protocol was conducted with the site of PGF2α injection alternated between neck and rump in beef cattle (n = 312) at the Ohio State University Agricultural Technical Institute and North Carolina State University. Blood samples (n = 75) were collected at controlled internal drug release insertion and at the time of artificial insemination (AI) to determine if progesterone (P4) and estrogen (E2) concentrations varied due to PGF2α injection site. All cattle were confirmed pregnant by ultrasonography at approximately 30 and 90 days after insemination in North Carolina and approximately 70 days after insemination in Ohio. Data were analyzed as randomized complete block designs in PROC GLIMMIX with animal as the experimental unit. Differences were declared significant at P < 0.05. Site of PGF2α injection, in either the neck or rump, did not affect (P > 0.05) overall conception rates in response to AI (58.4% and 55.6%, respectively). Altering PGF2α injection site did not impact P4, E2 concentrations, or the P4:E2 ratio at AI (P > 0.05). However, cattle inseminated after displaying estrus had greater (P < 0.05) pregnancy rates than timed AI (67.8 vs. 47.5%, respectively). First service conception rates and pregnancy rates were consistent with previous reports. Overall, altering the location of the PGF2α injection during ES did not change circulating hormone concentrations at AI or pregnancy rates; therefore, cattle producers should follow Beef Quality Assurance guidelines when administering ES protocols.


Assuntos
Bovinos/fisiologia , Dinoprosta/farmacologia , Hormônio Liberador de Gonadotropina/farmacologia , Inseminação Artificial/veterinária , Progesterona/farmacologia , Animais , Dinoprosta/administração & dosagem , Esquema de Medicação , Detecção do Estro/instrumentação , Feminino , Hormônio Liberador de Gonadotropina/administração & dosagem , Gravidez , Fatores de Tempo
8.
Issues Ment Health Nurs ; 36(6): 430-8, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26241569

RESUMO

Intimate partner violence (IPV) is a public health problem. The purpose of this study was to compare the effectiveness of the HELPP (Health, Education on Safety, and Legal Support and Resources in IPV Participant Preferred) intervention among IPV survivors. A sequential, transformative mixed-methods design was used. Participants were randomly assigned to one of three study groups: Online (ONL), Face-to-Face (FTF), and Waitlist Control (WLC). The HELPP intervention was offered to 32 adult female participants who were 45.2% Asian, 32.3% White, and 22.5% Black. Outcome measures were anxiety, depression, anger, personal, and social support. In total, 64% (n  =  20) of the participants reported having experienced IPV before the age of 18. The anger mean score pre-test to post-test difference was significant for ONL (p < 0.001) and WLC (p  =  0.01). The personal and social support pre-test to post-test mean score differences were significant for ONL (p < 0.001; p < 0.001) and WLC (p  =  0.01; p  =  0.006), respectively. The HELPP intervention (1) decreased anxiety, depression, anger, and (2) increased personal and social support in the ONL group. The HELPP information and intervention was shown to be feasible, acceptable, and effective among IPV survivors compared with participants in the WLC group. The WLC participants displayed (1) increased levels of anxiety, depression, and anger and (2) decreased levels of personal and social support, post-intervention. Further research could be conducted to determine if e-mail alone or e-mail plus mobile devices are more useful modes of delivering interventions.


Assuntos
Intervenção em Crise , Serviços de Saúde Mental , Sistemas On-Line , Apoio Social , Maus-Tratos Conjugais/psicologia , Telemedicina , Adulto , Ansiedade/etiologia , Ansiedade/prevenção & controle , Depressão/etiologia , Depressão/prevenção & controle , Emoções , Feminino , Humanos , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Projetos Piloto , Adulto Jovem
9.
Leuk Res ; 39(8): 913-20, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26138615

RESUMO

INTRODUCTION: Connective tissue growth factor (CTGF/CCN2) has been shown previously to be aberrantly expressed in a high proportion of paediatric precursor B cell acute lymphoblastic leukaemia (pre-B ALL), suggesting a potential oncogenic role in this tumour type. We therefore assessed CTGF mRNA transcript diversity in B-lineage ALL using primary patient specimens and cell lines. METHODS: CTGF mRNA expression was evaluated by quantitative real-time PCR and Northern blotting. We performed a structural analysis of CTGF mRNA by nested reverse-transcriptase PCR and examined CTGF protein diversity by immunoblotting. RESULTS: Northern blot analysis of pre-B ALL cell lines revealed short CTGF transcripts that were expressed in association with the active phase of cellular growth. Structural analysis confirmed the synthesis of several novel CTGF mRNA isoforms in B-lineage ALL cell lines that were uniformly characterised by the retention of the coding sequence for the C-terminal (CT) domain. One of these novel spliceforms was expressed in a majority (70%) of primary pre-B ALL patient specimens positive for canonical CTGF mRNA. Evidence that these alternative transcripts have coding potential was provided by cryptic CTGF proteins of predicted size detected by immunoblotting. CONCLUSION: This study identifies for the first time alternative splicing of the CTGF gene and shows that a short CTGF splice variant associated with cell proliferation is expressed in most cases of primary CTGF-positive pre-B ALL. This novel variant encoding only the CT domain may play a role in pre-B ALL tumorigenesis and/or progression.


Assuntos
Fator de Crescimento do Tecido Conjuntivo/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Transformação Celular Neoplásica/genética , Criança , Fator de Crescimento do Tecido Conjuntivo/química , Progressão da Doença , Perfilação da Expressão Gênica , Regulação Leucêmica da Expressão Gênica , Humanos , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , Estrutura Terciária de Proteína/genética , Células Tumorais Cultivadas
10.
Diagn Microbiol Infect Dis ; 82(4): 265-8, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26008122

RESUMO

The AmpliVue (Quidel, San Diego, CA, USA) and Illumigene (Meridian Biosciences, Cincinnati, OH, USA) molecular tests were compared for the detection of C. difficile toxin in fresh fecal samples from adult and pediatric patients. A total of 758 samples were collected, in 3 clinical sites: Nationwide Children's (Columbus, OH, USA), Penn State Hershey (Hershey, PA, USA), Primary Children's (Salt Lake City, UT, USA). Each site tested the fecal specimens using both assays. Any discordant results were resolved by performing toxigenic culture. There were 16 discordant samples among the 3 sites. Following discordant resolution, the combined performance for all 3 sites for sensitivity, specificity, PPV, and NPV for AmpliVue was 96.1%, 99.2%, 96.1%, and 99.2%, respectively, while for Illumigene was 96.1%, 99.8%, 99.2%, and 99.2%, respectively. The AmpliVue and Illumigene methods are both relatively rapid and simple to use, sensitive, and specific for detection of C. difficile toxin and demonstrate similar performance.


Assuntos
Toxinas Bacterianas/genética , Clostridioides difficile/genética , Infecções por Clostridium/diagnóstico , Diarreia/diagnóstico , Fezes/microbiologia , Técnicas de Diagnóstico Molecular/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Infecções por Clostridium/induzido quimicamente , Diarreia/induzido quimicamente , Feminino , Humanos , Lactente , Masculino , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Fatores de Tempo , Estados Unidos , Adulto Jovem
11.
Gene Ther ; 21(4): 444-9, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24572792

RESUMO

Resting human CD4 T cells are highly resistant to transfection or infection with lentiviral vectors derived from the human immunodeficiency virus. We now describe a flexible and efficient approach involving virus-like particles containing simian immunodeficiency virus lentiviral gene product protein X and pseudotyping with CXCR4-tropic HIV Env. This method permits effective genetic manipulation of these cells while preserving their naturally quiescent state. This technology can also be extended to primary lymphoid cultures where authentic cellular composition and functional relationships are preserved.


Assuntos
Linfócitos T CD4-Positivos/metabolismo , Técnicas de Transferência de Genes , Terapia Genética , Proteínas Virais/genética , Animais , Linfócitos T CD4-Positivos/patologia , Vetores Genéticos , HIV-1/genética , Humanos , Lentivirus/genética , Receptores CXCR4/genética , Receptores CXCR4/uso terapêutico , Vírus da Imunodeficiência Símia , Proteínas Virais/administração & dosagem , Proteínas Virais/uso terapêutico , Produtos do Gene env do Vírus da Imunodeficiência Humana/genética , Produtos do Gene env do Vírus da Imunodeficiência Humana/uso terapêutico
12.
Neuroscience ; 181: 226-33, 2011 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-21333717

RESUMO

Spinal muscular atrophy (SMA), a neurodegenerative disorder primarily affecting motor neurons, is the most common genetic cause of infant death. This incurable disease is caused by the absence of a functional SMN1 gene and a reduction in full length survival of motor neuron (SMN) protein. In this study, a neuroprotective function of SMN was investigated in differentiated human SH-SY5Y cells using an adenoviral vector to over-express SMN protein. The pro-survival capacity of SMN was assessed in an Akt/PI3-kinase inhibition (LY294002) model, as well as an oxidative stress (hydrogen peroxide) and excitotoxic (glutamate) model. SMN over-expression in SH-SY5Y cells protected against Akt/phosphatidylinositol 3-kinase (PI3-kinase) inhibition, but not oxidative stress, nor against excitotoxicity in rat cortical neurons. Western analysis of cell homogenates from SH-SY5Y cultures over-expressing SMN harvested pre- and post-Akt/PI3-kinase inhibition indicated that SMN protein inhibited caspase-3 activation via blockade of calpain-mediated procaspase-3 cleavage. This study has revealed a novel anti-apoptotic function for the SMN protein in differentiated SH-SY5Y cells. Finally, the cell death model described herein will allow the assessment of future therapeutic agents or strategies aimed at increasing SMN protein levels.


Assuntos
Apoptose/fisiologia , Calpaína/fisiologia , Caspase 3/metabolismo , Regulação Enzimológica da Expressão Gênica/fisiologia , Neurônios/metabolismo , Proteína 1 de Sobrevivência do Neurônio Motor/biossíntese , Proteína 1 de Sobrevivência do Neurônio Motor/genética , Animais , Linhagem Celular , Linhagem Celular Tumoral , Sobrevivência Celular/genética , Células Cultivadas , Ativação Enzimática/genética , Humanos , Neurônios/citologia , Ratos
13.
Med Image Anal ; 13(5): 809-17, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19682945

RESUMO

A constrained non-rigid registration (CNRR) algorithm for use in prostate image-guided adaptive radiotherapy is presented in a coherent mathematical framework. The registration algorithm is based on a global rigid transformation combined with a series of local injective non-rigid multi-resolution cubic B-spline Free Form Deformation (FFD) transformations. The control points of the FFD are used to non-rigidly constrain the transformation to the prostate, rectum, and bladder. As well, the control points are used to rigidly constrain the transformation to the estimated position of the pelvis, left femur, and right femur. The algorithm was tested with both 3D conformal radiotherapy (3DCRT) and intensity-modulated radiotherapy (IMRT) dose plan data sets. The 3DCRT dose plan set consisted of 10 fan-beam CT (FBCT) treatment-day images acquired from four different patients. The IMRT dose plan set consisted of 32 cone-beam CT (CBCT) treatment-day images acquired from 4 different patients. The CNRR was tested with different combinations of anatomical constraints and each test significantly outperformed both rigid and non-rigid registration at aligning constrained bones and critical organs. The CNRR results were used to adapt the dose plans to account for patient positioning errors as well as inter-day bone motion and intrinsic organ deformation. Each adapted dose plan improved performance by lowering radiation distribution to the rectum and bladder while increasing or maintaining radiation distribution to the prostate.


Assuntos
Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/radioterapia , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Radioterapia Assistida por Computador/métodos , Radioterapia Conformacional/métodos , Técnica de Subtração , Tomografia Computadorizada por Raios X/métodos , Algoritmos , Inteligência Artificial , Humanos , Masculino , Reconhecimento Automatizado de Padrão/métodos , Intensificação de Imagem Radiográfica/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
14.
Med Oncol ; 26(1): 73-7, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-18663611

RESUMO

Prostate cancer is the most common type of solid tumor and a leading cause of cancer-related death of men living in the developed world. In recent years, the molecular mechanisms involved in prostate cancer development and/or progression have been intensely studied and several genes have been identified. TGIFLX/Y (TGIFLX and TGIFLY) are members of the homeobox superfamily of genes whose function(s) is unknown. To investigate TGIFLX/Y mRNA expression in prostate cancer, we studied two different types of clinical samples, namely 60 prostate tumors and 15 cases of benign prostate hyperplasia (BPH), by RT-PCR. Our results revealed that most prostate tumors (73.5%) express at least one of these genes, although different patterns of TGIFLX/Y mRNA expression were observed. In some tumor samples the expression of both genes was detected, while in others no expression of either gene was observed. Notably, there was a significant correlation between expression of both TGIFLX and TGIFLY and a Gleason score of >or=6 (P = 0.038). By contrast, expression of TGIFLX/Y mRNA in BPH samples could not be detected. These results suggest an association of TGIFLX/Y expression with the progression of prostate cancer.


Assuntos
Proteínas de Homeodomínio , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , RNA Mensageiro/biossíntese , Idoso , Idoso de 80 Anos ou mais , Regulação Neoplásica da Expressão Gênica , Proteínas de Homeodomínio/biossíntese , Proteínas de Homeodomínio/genética , Humanos , Masculino , Pessoa de Meia-Idade , Hiperplasia Prostática/genética , Hiperplasia Prostática/metabolismo , Hiperplasia Prostática/patologia , Neoplasias da Próstata/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa
15.
Artigo em Inglês | MEDLINE | ID: mdl-18979817

RESUMO

A constrained non-rigid registration (CNRR) algorithm for use in updating prostate external beam image-guided radiotherapy treatment plans is presented in this paper. The developed algorithm is based on a multi-resolution cubic B-spline FFD transformation and has been tested and verified using 3D CT images from 10 sets of real patient data acquired from 4 different patients on different treatment days. The registration can be constrained to any combination of the prostate, rectum, bladder, pelvis, left femur, and right femur. The CNRR was tested with 5 different combinations of constraints and each test significantly outperformed both rigid and non-rigid registration at aligning constrained bones and critical organs. The CNRR was then used to update the treatment plans to account for articulated, rigid bone motion and non-rigid organ deformation. Each updated treatment plan outperformed the original treatment plan by increasing radiation dosage to the prostate and lowering radiation dosage to the rectum and bladder.


Assuntos
Imageamento Tridimensional/métodos , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/radioterapia , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Radioterapia Assistida por Computador/métodos , Técnica de Subtração , Tomografia Computadorizada por Raios X/métodos , Algoritmos , Inteligência Artificial , Humanos , Masculino , Reconhecimento Automatizado de Padrão/métodos , Intensificação de Imagem Radiográfica/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
16.
Artigo em Inglês | MEDLINE | ID: mdl-20126424

RESUMO

This paper tracks organ (prostate, rectum, bladder) overlap in a constrained non-rigid registration (NRR) algorithm to register computed tomographic (CT) images used in external beam prostate radiotherapy. The local motion of the organs is described by a hierarchical multi-resolution FFD based on cubic B-splines. Registration is achieved by minimizing a cost function which is a combination of three functions representing the overlap of the critical organs, image similarity and smoothness of the transformation. The constrained NRR algorithm generated better registration results when compared to an unconstrained NRR algorithm.

17.
Proc IEEE Int Symp Biomed Imaging ; 4193392: 740-743, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-20011132

RESUMO

This paper presents a novel free-form deformation registration algorithm with non-rigid constraints to capture the transformation between the planning day and treatment day CT images used for external beam radiotherapy for prostate cancer. The algorithm is constrained to the predetermined motion of a segmented organ, which is described by an injective free-form deformation (FFD) based on B-splines. The end goal is for the injective transformation to be used to update the radiotherapy plan to take into account bone and soft tissue deformation. The results of the algorithm have been compared to those achieved using rigid and fully non-rigid registration. The results clearly indicate that the constrained non-rigid registration algorithm presented in this paper performed much better at capturing the motion of the constrained organ, the bladder in this case, than the rigid or fully non-rigid registration algorithms.

18.
Leukemia ; 20(2): 304-12, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16357834

RESUMO

TLX1/HOX11, a DNA-binding homeodomain protein, was originally identified by virtue of its aberrant expression in T-cell leukemia and subsequently found to be crucial for normal spleen development. The precise mechanism of TLX1 function remains poorly understood, although it is known that it can act as both a transcriptional activator and repressor and can downregulate the Aldh1a1 gene in embryonic mouse spleen. Using a whole-genome PCR approach, we show here that TLX1 protein directly interacts with pericentromeric human satellite 2 DNA sequences. Such DNA is known to localize to heterochromatin, which among other roles has been implicated in gene silencing. The interaction was confirmed in vitro and in vivo by gel retardation and chromatin immunoprecipitation assays involving satellite 2 DNA, which contained sequences resembling TLX1 binding sites. Using immunofluorescence microscopy, TLX1 demonstrated a punctate pattern of staining in the nuclei of leukemic T-cells (ALL-SIL). Double labelling indicated that TLX1 colocalized with the centromeric protein CENP-B, demonstrating that the TLX1 foci corresponded to clusters of centromeric DNA. The novel interaction of TLX1 with constitutive heterochromatin adds an additional level of complexity to the intracellular functions of this transcriptional regulator and may have relevance to its roles in transcriptional repression and T-cell immortalization.


Assuntos
Centrômero/metabolismo , DNA Satélite/metabolismo , Proteínas de Homeodomínio/metabolismo , Leucemia Mieloide/metabolismo , Leucemia de Células T/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Linfócitos T/metabolismo , Doença Aguda , Linhagem Celular Tumoral , Centrômero/genética , DNA Satélite/genética , Proteínas de Homeodomínio/genética , Humanos , Técnicas In Vitro , Leucemia Mieloide/patologia , Leucemia de Células T/patologia , Reação em Cadeia da Polimerase/métodos , Proteínas Proto-Oncogênicas/genética , Linfócitos T/patologia , Células Tumorais Cultivadas
19.
Science ; 294(5544): 1105-8, 2001 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-11691994

RESUMO

Human immunodeficiency virus-1 (HIV-1) Vpr expression halts the proliferation of human cells at or near the G2 cell-cycle checkpoint. The transition from G2 to mitosis is normally controlled by changes in the state of phosphorylation and subcellular compartmentalization of key cell-cycle regulatory proteins. In studies of the intracellular trafficking of these regulators, we unexpectedly found that wild-type Vpr, but not Vpr mutants impaired for G2 arrest, induced transient, localized herniations in the nuclear envelope (NE). These herniations were associated with defects in the nuclear lamina. Intermittently, these herniations ruptured, resulting in the mixing of nuclear and cytoplasmic components. These Vpr-induced NE changes probably contribute to the observed cell-cycle arrest.


Assuntos
Núcleo Celular/metabolismo , Fase G2 , Produtos do Gene vpr/fisiologia , HIV-1/fisiologia , Lamina Tipo B , Membrana Nuclear/metabolismo , Transporte Ativo do Núcleo Celular , Proteínas de Ciclo Celular/metabolismo , Núcleo Celular/virologia , Ciclina B/metabolismo , Ciclina B1 , Citoplasma/metabolismo , Produtos do Gene vpr/genética , Células HeLa , Humanos , Laminas , Macrófagos/virologia , Microscopia de Fluorescência , Microscopia de Vídeo , Mitose , Mutação , Membrana Nuclear/ultraestrutura , Complexo de Proteínas Formadoras de Poros Nucleares/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Tirosina Quinases/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Transfecção , Integração Viral , Fosfatases cdc25/metabolismo , Produtos do Gene vpr do Vírus da Imunodeficiência Humana
20.
J Exp Med ; 194(10): 1407-19, 2001 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-11714748

RESUMO

Prior experiments in explants of human lymphoid tissue have demonstrated that human immunodeficiency virus type 1 (HIV-1) productively infects diverse cellular targets including T cells and tissue macrophages. We sought to determine the specific contribution of macrophages and T cells to the overall viral burden within lymphoid tissue. To block infection of macrophages selectively while preserving infection of T cells, we used viruses deficient for viral protein R (Vpr) that exhibit profound replication defects in nondividing cells in vitro. We inoculated tonsil histocultures with matched pairs of congenic viruses that differed only by the presence of a wild-type or truncated vpr gene. Although these viruses exhibited no reduction in the infection or depletion of T cells, the ability of the Vpr-deficient R5 virus to infect tissue macrophages was severely impaired compared with matched wild-type R5 virus. Interestingly, the Vpr-deficient R5 virus also exhibited a 50% reduction in overall virus replication compared with its wild-type counterpart despite the fact that macrophages represent a small fraction of the potential targets of HIV-1 infection in these tissues. Collectively, these data highlight the importance of tissue macrophages in local viral burden and further implicate roles for CC chemokine receptor 5, macrophages, and Vpr in the life cycle and pathogenesis of HIV-1.


Assuntos
Linfócitos T CD4-Positivos/virologia , Produtos do Gene vpr/fisiologia , HIV-1/fisiologia , Macrófagos/virologia , Carga Viral , Ciclo Celular , Humanos , Tecido Linfoide/virologia , Receptores CCR5/fisiologia , Produtos do Gene vpr do Vírus da Imunodeficiência Humana
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