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2.
J Chem Phys ; 159(2)2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37439468

RESUMO

The quantum adiabatic method, which maintains populations in their instantaneous eigenstates throughout the state evolution, is an established and often a preferred choice for state preparation and manipulation. Although it minimizes the driving cost significantly, its slow speed is a severe limitation in noisy intermediate-scale quantum era technologies. Since adiabatic paths are extensive in many physical processes, it is of broader interest to achieve adiabaticity at a much faster rate. Shortcuts to adiabaticity techniques, which overcome the slow adiabatic process by driving the system faster through non-adiabatic paths, have seen increased attention recently. The extraordinarily long lifetime of the long-lived singlet states (LLS) in nuclear magnetic resonance (NMR), established over the past decade, has opened several important applications ranging from spectroscopy to biomedical imaging. Various methods, including adiabatic methods, are already being used to prepare LLS. In this article, we report the use of counterdiabatic driving (CD) to speed up LLS preparation with faster drives. Using NMR experiments, we show that CD can give stronger LLS order in shorter durations than conventional adiabatic driving.

3.
Clin Imaging ; 77: 98-110, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33662714

RESUMO

The thymus is a primary lymphoid organ that plays a key role in the immune system development. Normally, it is located in the anterior mediastinum and it changes tissue composition with progressive fatty involution with age. The spectrum of pathological processes involving the thymus include enlargement, tumour development, and cystic change. In addition, other local pathology can mimic thymic disease. Differentiating these entities can be challenging; however, recognizing key features on imaging is essential to appropriately guide further investigation and therapy. The focus of this pictorial review will be to highlight the important distinguishing features of thymic hyperplasia, thymomas, thymic cysts, thymic neuroendocrine tumours (NETs), thymolipomas, mediastinal teratomas, and other mimics of thymic disease. Knowledge of the varying imaging findings on computed tomography and magnetic resonance imaging is valuable for radiologists to appropriately classify disease, avoid misdiagnosis, and expedite therapy.


Assuntos
Cisto Mediastínico , Timoma , Hiperplasia do Timo , Neoplasias do Timo , Adulto , Humanos , Cisto Mediastínico/diagnóstico por imagem , Hiperplasia do Timo/diagnóstico por imagem , Neoplasias do Timo/diagnóstico por imagem , Tomografia Computadorizada por Raios X
4.
Eur J Radiol Open ; 7: 100292, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33318969

RESUMO

Cholecystectomy is the gold standard surgical treatment for acute calculous cholecystitis. Only approximately 0.4 % of these patients subsequently develop choledocholithiasis. The incidence of hepatic abscesses in these patients is unknown, but is likely low, considering there are approximately 2-15 cases of hepatic abscesses per 100,000 people in the US. The authors report the case of a 62-year-old man whose CT scan revealed hepatic abscesses secondary to choledocholithiasis, eight years after a cholecystectomy.

5.
Zootaxa ; 4821(1): zootaxa.4821.1.5, 2020 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-33056333

RESUMO

Sinomicrurus macclellandi (Reinhardt, 1844) is a species of coral snakes distributed across the forests of Southeast Asia and the Himalayas. The species exhibits distinct forms across its range, and it has been classified into four subspecies. Calliophis macclellandi nigriventer Wall, 1908 a population from Western Himalayas, which was described as a variety, has not been attended to until now. Our study of a recently collected specimen from near Solan, Himachal Pradesh, India and existing museum material has allowed us to assess the validity of this population based on molecular and morphological data and has given us enough evidence to suggest its elevation to a species rank. Sinomicrurus nigriventer comb. nov. was found to be embedded within a clade comprising S. peinani, but not S. macclellandi s. l., with a genetic distance of 7-16% from its congeners. Morphologically, it differs from its congeners in having a reddish brown dorsum and a mid-dorsal black vertebral strip extending from the nape to the vent and with three thin bands on the tail, belly white with black smear up to the vent, tail dorsum with a few band-like blotches, and males with 230-235 ventral scales.


Assuntos
Elapidae , Florestas , Animais , Masculino
6.
Transplantation ; 103(4): 698-704, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30278018

RESUMO

BACKGROUND: Antibody-mediated rejection (AMR) in cardiac allograft recipients remains less well-understood than acute cellular rejection, is associated with worse outcomes, and portends a greater risk of developing chronic allograft vasculopathy. Diffuse immunohistochemical C4d staining of capillary endothelia in formalin-fixed, paraffin-embedded right ventricular endomyocardial biopsies is diagnostic of immunopathologic AMR but serves more as a late-stage marker. Infrared (IR) spectroscopy may be a useful tool in earlier detection of rejection. We performed mid-IR spectroscopy to identify a unique biochemical signature for AMR. METHODS: A total of 30 posttransplant formalin-fixed paraffin-embedded right ventricular tissue biopsies (14 positive for C4d and 16 negative for C4d) and 14 native heart biopsies were sectioned for IR analysis. Infrared images of entire sections were acquired and regions of interest from cardiomyocytes were identified. Extracted spectra were averaged across many pixels within each region of interest. Principal component analysis coupled with linear discriminant analysis and predictive classifiers were applied to the data. RESULTS: Comparison of averaged mid-IR spectra revealed unique features among C4d-positive, C4d-negative, and native heart biopsies. Principal component analysis coupled with linear discriminant analysis and classification models demonstrated that spectral features from the mid-IR fingerprint region of these 3 groups permitted accurate automated classification into each group. CONCLUSIONS: In cardiac allograft biopsies with immunopathologic AMR, IR spectroscopy reveals a biochemical signature unique to AMR compared with that of nonrejecting cardiac allografts and native hearts. Future study will focus on the predictive capabilities of this IR signature.


Assuntos
Rejeição de Enxerto/etiologia , Transplante de Coração/efeitos adversos , Miocárdio/patologia , Espectrofotometria Infravermelho/métodos , Adulto , Idoso , Anticorpos/imunologia , Biópsia , Complemento C4b/análise , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fragmentos de Peptídeos/análise
7.
IEEE Trans Med Imaging ; 38(5): 1304-1313, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30489266

RESUMO

Hyperspectral imaging (HSI) of tissue samples in the mid-infrared (mid-IR) range provides spectro-chemical and tissue structure information at sub-cellular spatial resolution. Disease states can be directly assessed by analyzing the mid-IR spectra of different cell types (e.g., epithelial cells) and sub-cellular components (e.g., nuclei), provided that we can accurately classify the pixels belonging to these components. The challenge is to extract information from hundreds of noisy mid-IR bands at each pixel, where each band is not very informative in itself, making annotations of unstained tissue HSI images particularly tricky. Because the tissue structure is not necessarily identical between the two sections, only a few regions in unstained HSI image can be annotated with high confidence, even when serial (or adjacent) hematoxylin and eosin stained section is used as a visual guide. In order to completely use both labeled and unlabeled pixels in training images, we have developed an HSI pixel classification method that uses semi-supervised learning for both spectral dimension reduction and hierarchical pixel clustering. Compared to the supervised classifiers, the proposed method was able to account for the vast differences in the spectra of sub-cellular components of the same cell type and to achieve an F1 score of 71.18% on twofold cross-validation across 20 tissue images. To generate further interest in this promising modality, we have released our source code and also showed that disease classification is straightforward after HSI image segmentation.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Imagem Óptica/métodos , Espectrofotometria Infravermelho/métodos , Aprendizado de Máquina Supervisionado , Análise por Conglomerados , Colo/diagnóstico por imagem , Doenças do Colo/diagnóstico por imagem , Humanos , Interpretação de Imagem Assistida por Computador/métodos
8.
Med J Armed Forces India ; 74(1): 72-75, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29386736

RESUMO

Large staghorn calculi in unascended pelvic kidneys and in normally located kidneys with anatomy unsuitable for percutaneous nephrolithotomy have to be treated via pyelolithotomy. When performed laparoscopically, the extraction of these staghorn calculi, without extending skin incision at the port site is challenging. We describe the successful use of laparoscopic laser lithotripsy, intracorporeally, with the entrapped calculus inside the endocatch bag, for fragmentation and retrieval without extension of skin incision.

9.
Sci Rep ; 8(1): 686, 2018 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-29330374

RESUMO

Renal transplants have not seen a significant improvement in their 10-year graft life. Chronic damage accumulation often leads to interstitial fibrosis and tubular atrophy (IF/TA) and thus graft function loss over time. For this reason, IF/TA has been the chief suspect for a potential prognostic marker for long term outcomes. In this study, we have used infrared spectroscopic (IR) imaging to interrogate the biochemistry of regions of fibrosis from renal transplant biopsies to identify a biochemical signature that can predict rapid progression of fibrosis. IR imaging represents an approach that permits label-free biochemical imaging of human tissues towards identifying novel biomarkers for disease diagnosis or prognosis. Two cohorts were identified as progressors (n = 5, > 50% fibrosis increase between time points) and non-progressors (n = 5, < 5% increase between time points). Each patient had an early time point and late time point biopsy. Collagen associated carbohydrate moieties (ν(C-O), 1035 cm-1 and ν(C-O-C),1079 cm-1) spectral ratios demonstrated good separation between the two cohorts (p = 0.001). This was true for late and early time point biopsies suggesting the regions of fibrosis are biochemically altered in cases undergoing progressive fibrosis. Thus, IR imaging can potentially predict rapid progression of fibrosis using histologically normal early time point biopsies.


Assuntos
Rim/patologia , Lasers Semicondutores , Análise Discriminante , Progressão da Doença , Fibrose , Humanos , Rim/diagnóstico por imagem , Análise de Componente Principal , Espectrofotometria Infravermelho , Transplantados
10.
J Shoulder Elbow Surg ; 27(1): 17-22, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28941971

RESUMO

HYPOTHESIS: We hypothesized that National Football League (NFL) players sustaining a shoulder destabilizing injury could return to play (RTP) successfully at a high rate regardless of treatment type. METHODS: We identified and evaluated 83 NFL players who sustained an in-season shoulder instability event while playing in the NFL. NFL RTP, incidence of surgery, time to RTP, recurrent instability events, seasons/games played after the injury, and demographic data were collected. Overall RTP was determined, and players who did and did not undergo operative repair were compared. RESULTS: Ninety-two percent of NFL players returned to NFL regular season play at a median of 0.0 weeks in those sustaining a shoulder subluxation and 3.0 weeks in those sustaining a dislocation who did not undergo surgical repair (P = .029). Players who underwent operative repair returned to play at a median of 39.3 weeks. Forty-seven percent of players had a recurrent instability event. For players who were able to RTP, those who underwent surgical repair (31%) had a lower recurrence rate (26% vs. 55%, P = .021) and longer interval between a recurrent instability event after RTP (14.7 vs. 2.5 weeks, P = .050). CONCLUSION: There is a high rate of RTP after shoulder instability events in NFL players. Players who sustain shoulder subluxations RTP faster but are more likely to experience recurrent instability than those with shoulder dislocations. Surgical stabilization of the shoulder after an instability event decreases the chances of a second instability event and affords a player a greater interval between the initial injury and a recurrent event.


Assuntos
Tratamento Conservador , Futebol Americano/lesões , Instabilidade Articular/terapia , Traumatismos Ocupacionais/terapia , Volta ao Esporte , Luxação do Ombro/terapia , Lesões do Ombro/terapia , Adulto , Humanos , Instabilidade Articular/cirurgia , Masculino , Traumatismos Ocupacionais/cirurgia , Recidiva , Luxação do Ombro/cirurgia , Lesões do Ombro/cirurgia , Fatores de Tempo , Adulto Jovem
11.
Int J Biochem Cell Biol ; 92: 14-17, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28888785

RESUMO

Infrared spectroscopic tissue imaging is a potentially powerful adjunct tool to current histopathology techniques. By coupling the biochemical signature obtained through infrared spectroscopy to the spatial information offered by microscopy, this technique can selectively analyze the chemical composition of different features of unlabeled, unstained tissue sections. In the past, the tissue features that have received the most interest were parenchymal and epithelial cells, chiefly due to their involvement in dysplasia and progression to carcinoma; however, the field has recently turned its focus toward stroma and areas of fibrotic change. These components of tissue present an untapped source of biochemical information that can shed light on many diverse disease processes, and potentially hold useful predictive markers for these same pathologies. Here we review the recent applications of infrared spectroscopic imaging to stromal and fibrotic regions of diseased tissue, and explore the potential of this technique to advance current capabilities for tissue analysis.


Assuntos
Fibrose/diagnóstico por imagem , Fibrose/metabolismo , Imagem Molecular/métodos , Espectrofotometria Infravermelho/métodos , Animais , Humanos , Imagem Molecular/instrumentação , Espectrofotometria Infravermelho/instrumentação
12.
Vib Spectrosc ; 91: 77-82, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28781430

RESUMO

Fourier transform infrared (FT-IR) microscopy was used to image tissue samples from twenty patients diagnosed with thyroid carcinoma. The spectral data were then used to differentiate between follicular thyroid carcinoma and follicular variant of papillary thyroid carcinoma using principle component analysis coupled with linear discriminant analysis and a Naïve Bayesian classifier operating on a set of computed spectral metrics. Classification of patients' disease type was accomplished by using average spectra from a wide region containing follicular cells, colloid, and fibrosis; however, classification of disease state at the pixel level was only possible when the extracted spectra were limited to follicular epithelial cells in the samples, excluding the relatively uninformative areas of fibrosis. The results demonstrate the potential of FT-IR microscopy as a tool to assist in the difficult diagnosis of these subtypes of thyroid cancer, and also highlights the importance of selectively and separately analyzing spectral information from different features of a tissue of interest.

13.
Biomed Opt Express ; 7(6): 2419-24, 2016 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-27375956

RESUMO

The importance of stroma as a rich diagnostic region in tissue biopsies is growing as there is an increasing understanding that disease processes in multiple organs can affect the composition of adjacent connective tissue regions. This may be especially true in the liver, since this organ's central metabolic role exposes it to multiple disease processes. We use quantum cascade laser infrared spectroscopic imaging to study changes in the chemical status of hepatocytes and fibrotic regions of liver tissue that result from the progression of liver cirrhosis to hepatocellular carcinoma and the potentially confounding effects of diabetes mellitus.

14.
Kidney Int ; 90(1): 226, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27312453
15.
Kidney Int ; 89(5): 1153-1159, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26924056

RESUMO

Routine histology, the current gold standard, involves staining for specific biomolecules. However, untapped biochemical information in tissue can be gathered using biochemical imaging. Infrared spectroscopy is an emerging modality that allows label-free chemical imaging to derive biochemical information (such as protein, lipids, DNA, collagen) from tissues. Here we employed this technology in order to better predict the development of diabetic nephropathy. Using human primary kidney biopsies or nephrectomies, we obtained tissue from 4 histologically normal kidneys, 4 histologically normal kidneys from diabetic subjects, and 5 kidneys with evidence of diabetic nephropathy. A biochemical signature of diabetic nephropathy was derived that enabled prediction of nephropathy based on the ratio of only 2 spectral frequencies. Nonetheless, using the entire spectrum of biochemical information, we were able to detect renal disease with near-perfect accuracy. Additionally, study of sequential protocol biopsies from 3 transplanted kidneys showed biochemical changes even prior to clinical manifestation of diabetic nephropathy. Thus, infrared imaging can identify critical biochemical alterations that precede morphologic changes, potentially allowing for earlier intervention.


Assuntos
Nefropatias Diabéticas/metabolismo , Rim/metabolismo , Espectrofotometria Infravermelho/métodos , Adulto , Biomarcadores/metabolismo , Biópsia , Estudos de Casos e Controles , Nefropatias Diabéticas/patologia , Nefropatias Diabéticas/cirurgia , Progressão da Doença , Humanos , Rim/patologia , Rim/cirurgia , Transplante de Rim , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Recidiva , Reprodutibilidade dos Testes , Fatores de Tempo , Resultado do Tratamento
16.
J Vis Exp ; (95): 52332, 2015 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-25650759

RESUMO

High-definition Fourier Transform Infrared (FT-IR) spectroscopic imaging is an emerging approach to obtain detailed images that have associated biochemical information. FT-IR imaging of tissue is based on the principle that different regions of the mid-infrared are absorbed by different chemical bonds (e.g., C=O, C-H, N-H) within cells or tissue that can then be related to the presence and composition of biomolecules (e.g., lipids, DNA, glycogen, protein, collagen). In an FT-IR image, every pixel within the image comprises an entire Infrared (IR) spectrum that can give information on the biochemical status of the cells that can then be exploited for cell-type or disease-type classification. In this paper, we show: how to obtain IR images from human tissues using an FT-IR system, how to modify existing instrumentation to allow for high-definition imaging capabilities, and how to visualize FT-IR images. We then present some applications of FT-IR for pathology using the liver and kidney as examples. FT-IR imaging holds exciting applications in providing a novel route to obtain biochemical information from cells and tissue in an entirely label-free non-perturbing route towards giving new insight into biomolecular changes as part of disease processes. Additionally, this biochemical information can potentially allow for objective and automated analysis of certain aspects of disease diagnosis.


Assuntos
Rim/patologia , Fígado/patologia , Patologia/métodos , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Diagnóstico por Imagem/métodos , Análise de Fourier , Humanos
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