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1.
Phys Chem Chem Phys ; 25(28): 18990-18997, 2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37415566

RESUMO

The demand for fluorescent organic dyes across a broad range of applications has led to investigation into tuneable emission dyes. The tuneable nature of these dyes makes them desirable for applications in a variety of fields, including organic light-emitting diodes (OLEDs), optical sensing devices, and fluorescence imaging. In recent investigations, there have only been a handful of mechanisms used to tune emission. Herein, we present four novel perylene-acene dyads that undergo solvent tuneable emission, and propose a novel mechanism for this tuneability based on the presence of a charge transfer state. These dyes were shown to reach photoluminescence quantum efficiencies (PLQEs) as high as 45%, depending on the solvent, showing the ability for this mechanism to be used to access higher PLQE tuneable emission.

2.
ACS Appl Mater Interfaces ; 15(14): 17914-17921, 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-36975316

RESUMO

Luminescent solar concentrators (LSCs) concentrate light via luminescence within a planar-waveguide and have potential use for building-integrated photovoltaics. However, their commercialization and potential applications are currently hindered greatly by photon reabsorption, where emitted waveguided light is parasitically reabsorbed by a luminophore. Nanotetrapod semiconductor materials have been theorized to be excellent luminophores for LSCs owing to their inherently large Stokes shifts. Here we present the first nanotetrapod-based LSCs (5 × 5 × 0.3 cm3) reported in the literature. External quantum efficiencies as high as 4.9 ± 0.5% were achieved under AM1.5G conditions. We also perform an in-depth investigation by optical characterization of the different operational metrics of our nanotetrapod-based LSCs and show reabsorption to be eliminated (mean number of average reabsorption events per photon equal to 0.00) in our most extended nanotetrapod devices.

3.
ACS Phys Chem Au ; 2(5): 364-387, 2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-36855686

RESUMO

Hybrid nanomaterials (HNs), the combination of organic semiconductor ligands attached to nanocrystal semiconductor quantum dots, have applications that span a range of practical fields, including biology, chemistry, medical imaging, and optoelectronics. Specifically, HNs operate as discrete, tunable systems that can perform prompt fluorescence, energy transfer, singlet fission, upconversion, and/or thermally activated delayed fluorescence. Interest in HNs has naturally grown over the years due to their tunability and broad spectrum of applications. This Review presents a brief introduction to the components of HNs, before expanding on the characterization and applications of HNs. Finally, the future of HN applications is discussed.

4.
J Med Case Rep ; 15(1): 544, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34724974

RESUMO

BACKGROUND: This report describes the case of a patient whose pituitary microadenoma resolved after he contracted coronavirus disease 2019. To our knowledge, this is one of the first reported cases of pituitary tumor resolution due to viral illness. We present this case to further investigate the relationship between inflammatory response and tumor remission. CASE PRESENTATION: A 32-year-old man in Yemen presented to the hospital with fever, low blood oxygen saturation, and shortness of breath. The patient was diagnosed with coronavirus disease 2019. Past medical history included pituitary microadenoma that was diagnosed using magnetic resonance imaging and secondary adrenal insufficiency, which was treated with steroids. Due to the severity of coronavirus disease 2019, he was treated with steroids and supportive care. Three months after his initial presentation to the hospital, brain magnetic resonance imaging was performed and compared with past scans. Magnetic resonance imaging revealed changes in the microadenoma, including the disappearance of the hypointense lesion and hyperintense enhancement observed on the previous scan. CONCLUSIONS: Pituitary adenomas rarely undergo spontaneous resolution. Therefore, we hypothesized that tumor resolution was secondary to an immune response to coronavirus disease 2019.


Assuntos
Adenoma , COVID-19 , Neoplasias Hipofisárias , Adenoma/complicações , Adenoma/diagnóstico por imagem , Adulto , Humanos , Imageamento por Ressonância Magnética , Masculino , Neoplasias Hipofisárias/diagnóstico por imagem , Neoplasias Hipofisárias/tratamento farmacológico , SARS-CoV-2
5.
J Exp Biol ; 224(16)2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34412111

RESUMO

Human bipedalism entails relatively short strides compared with facultatively bipedal primates. Unique non-sagittal-plane motions associated with bipedalism may account for part of this discrepancy. Pelvic rotation anteriorly translates the hip, contributing to bipedal stride length (i.e. the 'pelvic step'). Facultative bipedalism in non-human primates entails much larger pelvic rotation than in humans, suggesting that a larger pelvic step may contribute to their relatively longer strides. We collected data on the pelvic step in bipedal chimpanzees and over a wide speed range of human walking. At matched dimensionless speeds, humans have 26.7% shorter dimensionless strides, and a pelvic step 5.4 times smaller than bipedal chimpanzees. Differences in pelvic rotation explain 31.8% of the difference in dimensionless stride length between the two species. We suggest that relative stride lengths and the pelvic step have been significantly reduced throughout the course of hominin evolution.


Assuntos
Marcha , Caminhada , Animais , Evolução Biológica , Fenômenos Biomecânicos , Humanos , Pan troglodytes , Pelve
6.
Nature ; 587(7833): 258-263, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33116307

RESUMO

The anterolateral pathway consists of ascending spinal tracts that convey pain, temperature and touch information from the spinal cord to the brain1-4. Projection neurons of the anterolateral pathway are attractive therapeutic targets for pain treatment because nociceptive signals emanating from the periphery are channelled through these spinal projection neurons en route to the brain. However, the organizational logic of the anterolateral pathway remains poorly understood. Here we show that two populations of projection neurons that express the structurally related G-protein-coupled receptors (GPCRs) TACR1 and GPR83 form parallel ascending circuit modules that cooperate to convey thermal, tactile and noxious cutaneous signals from the spinal cord to the lateral parabrachial nucleus of the pons. Within this nucleus, axons of spinoparabrachial (SPB) neurons that express Tacr1 or Gpr83 innervate distinct sets of subnuclei, and strong optogenetic stimulation of the axon terminals induces distinct escape behaviours and autonomic responses. Moreover, SPB neurons that  express Gpr83 are highly sensitive to cutaneous mechanical stimuli and receive strong synaptic inputs from both high- and low-threshold primary mechanosensory neurons. Notably, the valence associated with activation of SPB neurons that express Gpr83 can be either positive or negative, depending on stimulus intensity. These findings reveal anatomically, physiologically and functionally distinct subdivisions of the SPB tract that underlie affective aspects of touch and pain.


Assuntos
Vias Neurais , Dor/fisiopatologia , Medula Espinal/citologia , Medula Espinal/fisiologia , Tato/fisiologia , Animais , Axônios/metabolismo , Feminino , Masculino , Mecanotransdução Celular , Camundongos , Filosofia , Receptores Acoplados a Proteínas G/genética , Células Receptoras Sensoriais/metabolismo , Pele/inervação , Sinapses/metabolismo
7.
Nature ; 585(7825): 357-362, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32939066

RESUMO

Array programming provides a powerful, compact and expressive syntax for accessing, manipulating and operating on data in vectors, matrices and higher-dimensional arrays. NumPy is the primary array programming library for the Python language. It has an essential role in research analysis pipelines in fields as diverse as physics, chemistry, astronomy, geoscience, biology, psychology, materials science, engineering, finance and economics. For example, in astronomy, NumPy was an important part of the software stack used in the discovery of gravitational waves1 and in the first imaging of a black hole2. Here we review how a few fundamental array concepts lead to a simple and powerful programming paradigm for organizing, exploring and analysing scientific data. NumPy is the foundation upon which the scientific Python ecosystem is constructed. It is so pervasive that several projects, targeting audiences with specialized needs, have developed their own NumPy-like interfaces and array objects. Owing to its central position in the ecosystem, NumPy increasingly acts as an interoperability layer between such array computation libraries and, together with its application programming interface (API), provides a flexible framework to support the next decade of scientific and industrial analysis.


Assuntos
Biologia Computacional/métodos , Matemática , Linguagens de Programação , Design de Software
8.
Nat Methods ; 17(3): 261-272, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32015543

RESUMO

SciPy is an open-source scientific computing library for the Python programming language. Since its initial release in 2001, SciPy has become a de facto standard for leveraging scientific algorithms in Python, with over 600 unique code contributors, thousands of dependent packages, over 100,000 dependent repositories and millions of downloads per year. In this work, we provide an overview of the capabilities and development practices of SciPy 1.0 and highlight some recent technical developments.


Assuntos
Algoritmos , Biologia Computacional/métodos , Linguagens de Programação , Software , Biologia Computacional/história , Simulação por Computador , História do Século XX , História do Século XXI , Modelos Lineares , Modelos Biológicos , Dinâmica não Linear , Processamento de Sinais Assistido por Computador
10.
Front Neurosci ; 12: 727, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30405329

RESUMO

We describe a project-based introduction to reproducible and collaborative neuroimaging analysis. Traditional teaching on neuroimaging usually consists of a series of lectures that emphasize the big picture rather than the foundations on which the techniques are based. The lectures are often paired with practical workshops in which students run imaging analyses using the graphical interface of specific neuroimaging software packages. Our experience suggests that this combination leaves the student with a superficial understanding of the underlying ideas, and an informal, inefficient, and inaccurate approach to analysis. To address these problems, we based our course around a substantial open-ended group project. This allowed us to teach: (a) computational tools to ensure computationally reproducible work, such as the Unix command line, structured code, version control, automated testing, and code review and (b) a clear understanding of the statistical techniques used for a basic analysis of a single run in an MR scanner. The emphasis we put on the group project showed the importance of standard computational tools for accuracy, efficiency, and collaboration. The projects were broadly successful in engaging students in working reproducibly on real scientific questions. We propose that a course on this model should be the foundation for future programs in neuroimaging. We believe it will also serve as a model for teaching efficient and reproducible research in other fields of computational science.

11.
Indian J Pathol Microbiol ; 60(2): 272-274, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28631653

RESUMO

Classical Hodgkin's lymphoma (CHL) presenting with exclusively pulmonary symptoms is very unusual. We report two cases of CHL with atypical clinical presentations mimicking pulmonary infections. The first case represents a stage IV CHL with secondary lung involvement, and the second case demonstrates a very rare case of CHL with isolated lung involvement, also known as primary pulmonary Hodgkin's lymphoma. The second patient was initially misdiagnosed and treated with six months of antibiotics before the correct diagnosis was made by a lung biopsy. Both patients received chemotherapy; one patient achieved complete remission and the other achieved near-complete remission.


Assuntos
Doença de Hodgkin/diagnóstico , Doença de Hodgkin/patologia , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/patologia , Adulto , Antineoplásicos/uso terapêutico , Broncoscopia , Técnicas Citológicas , Histocitoquímica , Doença de Hodgkin/diagnóstico por imagem , Doença de Hodgkin/tratamento farmacológico , Humanos , Imuno-Histoquímica , Antígeno Ki-1/análise , Antígenos Comuns de Leucócito/análise , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/tratamento farmacológico , Masculino , Microscopia , Tomografia por Raios X , Resultado do Tratamento
12.
Int J Surg Pathol ; 25(7): 623-628, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28449607

RESUMO

Adenocarcinoma ex-goblet cell carcinoid is a very rare and histologically unique appendiceal malignancy with dual glandular and neuroendocrine differentiation. There is a high incidence of this tumor among middle-aged women with metastasis to the gynecologic tract with the mode of metastasis following peritoneal spread rather than hematogenous distribution. Adenocarcinoma ex-goblet cell carcinoid can spread to any peritoneal site including ovaries or omentum. We report a 37-year-old healthy woman who initially presented with right lower quadrant abdominal pain and pseudomyxoma peritonei. Histopathology of the appendectomy specimen revealed an adenocarcinoma ex-goblet cell carcinoid, signet ring cell type. Follow-up right hemicolectomy, omentectomy, bilateral salpingo-oophorectomy, and regional peritoneal resections revealed metastatic involvement by adenocarcinoma ex-goblet cell carcinoid, signet ring cell type. In this report, we describe a case of appendiceal adenocarcinoma ex goblet cell carcinoid with metastases to Meckel's diverticulum and areas of pelvic endometriosis, which have not been previously reported.


Assuntos
Adenocarcinoma/secundário , Neoplasias do Apêndice/patologia , Tumor Carcinoide/secundário , Endometriose/patologia , Neoplasias do Íleo/secundário , Neoplasias Peritoneais/secundário , Pseudomixoma Peritoneal/patologia , Adenocarcinoma/cirurgia , Adulto , Apendicectomia , Neoplasias do Apêndice/cirurgia , Apêndice/cirurgia , Biópsia , Colectomia , Endometriose/cirurgia , Feminino , Humanos , Neoplasias do Íleo/cirurgia , Divertículo Ileal/patologia , Omento/patologia , Omento/cirurgia , Ovário/patologia , Ovário/cirurgia , Neoplasias Peritoneais/cirurgia , Salpingo-Ooforectomia
13.
Case Rep Pathol ; 2017: 2758769, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28255489

RESUMO

Ulcerative colitis has long been linked with an increased risk for colonic adenocarcinoma, whereas Crohn's disease (CD) has recently been reported to pose a similar increased risk. We report a 33-year-old healthy female with no family history who presented with abdominal pain and a colon mass. Histopathology revealed a moderately differentiated adenocarcinoma extending through the muscularis propria with metastatic lymph nodes and intact mismatch repair proteins by immunohistochemical expression and gene sequencing. The nonneoplastic grossly uninvolved background mucosa showed marked crypt distortion, crypt abscesses, CD-like lymphoid hyperplasia, transmural inflammation, and reactive epithelial atypia. Additional patient questioning revealed frequent loose stools since she was a teenager leading to diagnosis of a previously undiagnosed CD without primary sclerosing cholangitis (PSC). The adenocarcinoma is suspected to be related to the underlying CD. Newly diagnosed adenocarcinoma in a young female as the presenting sign for CD in the absence of PSC is extremely rare.

15.
Case Rep Pathol ; 2016: 1934759, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27738541

RESUMO

Adenocarcinoma with osteoblastic metastases is classically seen in prostate, breast, and lung primaries. Less common primary sites include thyroid, kidney, and stomach. We present two cases of primary gastrointestinal adenocarcinoma with metastatic osteoblastic activity from two previously unreported sites. The first case represents an esophageal adenocarcinoma arising in a background of intestinal metaplasia that metastasized with osteoblastic activity to the deltoid muscle. The second case demonstrates a Stage IV sigmoid colon adenocarcinoma with osteoblastic metastases to the liver and lymph nodes. The findings indicate that metastases from various gastrointestinal primary adenocarcinomas can have prominent bone formation.

16.
Pathol Int ; 66(8): 438-43, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27439364

RESUMO

At our institution, percent tumor burden in prostate core biopsies is quantified using variations of one of two methods. Measurement by the Aggregate method reports only adenocarcinoma and omits intervening stroma and benign prostatic glands while the Discontinuous method includes the intervening stroma and benign glands between distinct foci of adenocarcinoma. In this study, we selected cases with 12-part core biopsies that were followed by a radical prostatectomy within two years. Interestingly, we found that when adenocarcinoma involved prostate 12-part core biopsies and subsequent resection unilaterally, there is no significant difference in absolute percentage of tumor using either measuring method (P = 0.4). In contrast, when adenocarcinoma involved the biopsies unilaterally and subsequent prostatectomy bilaterally, the two measurement methods had a statistically significant difference in percentage scores (P = 0.002). In the study cohort, other factors including Gleason score (P = 0.88) and total number of adenocarcinoma-involved cores (P = 0.27) did not introduce any significant correlation with bilateral involvement. In this study, we found that biopsies that discontinuously and unilaterally involve half of a prostate are much more likely to involve both lobes than those that are unilateral and present in nodular aggregates.


Assuntos
Adenocarcinoma/patologia , Neoplasias da Próstata/patologia , Biópsia com Agulha de Grande Calibre , Humanos , Masculino , Estadiamento de Neoplasias/métodos , Prostatectomia
17.
J Med Chem ; 58(23): 9309-33, 2015 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-26580420

RESUMO

A number of indole-3-glyoxylamides have previously been reported as tubulin polymerization inhibitors, although none has yet been successfully developed clinically. We report here a new series of related compounds, modified according to a strategy of reducing aromatic ring count and introducing a greater degree of saturation, which retain potent tubulin polymerization activity but with a distinct SAR from previously documented libraries. A subset of active compounds from the reported series is shown to interact with tubulin at the colchicine binding site, disrupt the cellular microtubule network, and exert a cytotoxic effect against multiple cancer cell lines. Two compounds demonstrated significant tumor growth inhibition in a mouse xenograft model of head and neck cancer, a type of the disease which often proves resistant to chemotherapy, supporting further development of the current series as potential new therapeutics.


Assuntos
Antineoplásicos/química , Antineoplásicos/uso terapêutico , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Indóis/química , Indóis/uso terapêutico , Moduladores de Tubulina/química , Moduladores de Tubulina/uso terapêutico , Animais , Antineoplásicos/farmacocinética , Células CACO-2 , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Neoplasias de Cabeça e Pescoço/metabolismo , Neoplasias de Cabeça e Pescoço/patologia , Xenoenxertos , Humanos , Indóis/farmacocinética , Masculino , Camundongos , Camundongos Nus , Microtúbulos/efeitos dos fármacos , Microtúbulos/metabolismo , Microtúbulos/patologia , Transplante de Neoplasias , Relação Estrutura-Atividade , Tubulina (Proteína)/metabolismo , Tubulina (Proteína)/ultraestrutura , Moduladores de Tubulina/farmacocinética
18.
Diagn Cytopathol ; 43(3): 238-42, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24962101

RESUMO

Endobronchial ultrasound-guided fine needle aspiration (EBUS-FNA) is a safe and minimally invasive bronchoscopic technique that allows both visualization and cytologic sampling with a high diagnostic yield in a patient with mediastinal lymphadenopathy. Besides the most common indication of staging for a patient with a primary lung carcinoma, EBUS-FNA can be used to identify benign infectious and noninfectious processes as well as lymphoma and malignancy of unknown primary. Triaging of procured specimen for diagnostic, prognostic, and therapeutic ancillary studies requires appropriate clinical information at the time of rapid on site evaluation (ROSE) of smears. This case report demonstrates a young, previously healthy nonsmoker presenting clinically with cough, hemoptysis, and a 1.7 cm enlarged subcarinal lymph node by imaging. EBUS-FNA obtained smears from the lymph node revealed a pleomorphic population of smaller cells with a low nuclear to cytoplasmic ratio and prominent nucleoli, and larger cells had nuclei with bizarre shapes, mitoses, multinucleation, enlarged nucleoli, and pigmentation in a background of lymphocytes. The cytomorphologic and immunohistochemical workup of this case confirmed the unexpected diagnosis of metastatic melanoma. This result was a complete surprise to the clinical team managing the patient and prompted a thorough clinical workup. Subcarinal lymphadenopathy with metastatic malignant melanoma as the cause is rare. This case report highlights how ROSE and appropriate triaging of specimen were crucial in appropriately working up this case. We also survey the literature to review the reported unusual presentations of metastatic melanoma.


Assuntos
Hemoptise/patologia , Doenças Linfáticas/patologia , Melanoma/patologia , Broncoscopia , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico , Humanos , Achados Incidentais , Linfonodos/patologia , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Fumar
19.
Front Neuroinform ; 8: 8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24600385

RESUMO

Diffusion Imaging in Python (Dipy) is a free and open source software project for the analysis of data from diffusion magnetic resonance imaging (dMRI) experiments. dMRI is an application of MRI that can be used to measure structural features of brain white matter. Many methods have been developed to use dMRI data to model the local configuration of white matter nerve fiber bundles and infer the trajectory of bundles connecting different parts of the brain. Dipy gathers implementations of many different methods in dMRI, including: diffusion signal pre-processing; reconstruction of diffusion distributions in individual voxels; fiber tractography and fiber track post-processing, analysis and visualization. Dipy aims to provide transparent implementations for all the different steps of dMRI analysis with a uniform programming interface. We have implemented classical signal reconstruction techniques, such as the diffusion tensor model and deterministic fiber tractography. In addition, cutting edge novel reconstruction techniques are implemented, such as constrained spherical deconvolution and diffusion spectrum imaging (DSI) with deconvolution, as well as methods for probabilistic tracking and original methods for tractography clustering. Many additional utility functions are provided to calculate various statistics, informative visualizations, as well as file-handling routines to assist in the development and use of novel techniques. In contrast to many other scientific software projects, Dipy is not being developed by a single research group. Rather, it is an open project that encourages contributions from any scientist/developer through GitHub and open discussions on the project mailing list. Consequently, Dipy today has an international team of contributors, spanning seven different academic institutions in five countries and three continents, which is still growing.

20.
Front Neurosci ; 6: 175, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23248578

RESUMO

Diffusion MR data sets produce large numbers of streamlines which are hard to visualize, interact with, and interpret in a clinically acceptable time scale, despite numerous proposed approaches. As a solution we present a simple, compact, tailor-made clustering algorithm, QuickBundles (QB), that overcomes the complexity of these large data sets and provides informative clusters in seconds. Each QB cluster can be represented by a single centroid streamline; collectively these centroid streamlines can be taken as an effective representation of the tractography. We provide a number of tests to show how the QB reduction has good consistency and robustness. We show how the QB reduction can help in the search for similarities across several subjects.

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