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1.
J Phys Condens Matter ; 33(2): 025802, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33055379

RESUMO

We explored the electronic and magnetic properties of the lanthanide double perovskite Dy2FeCoO6 by combining magnetization, Raman and Mössbauer spectroscopy and neutron diffraction along with density functional theory (DFT) calculations. Our magnetization measurements revealed two magnetic phase transitions in Dy2FeCoO6. First, a paramagnetic to antiferromagnetic transition at T N = 248 K and subsequently, a spin reorientation transition at T SR = 86 K. In addition, a field-induced magnetic phase transition with a critical field of H c ≈ 20 kOe is seen at 2 K. Neutron diffraction data suggested cation-disordered orthorhombic structure for Dy2FeCoO6 in Pnma space group which is supported by Raman scattering results. The magnetic structures ascertained through representational analysis indicate that at T N, a paramagnetic state is transformed to Γ5(Cx, Fy, Az) antiferromagnetic structure while, at T SR, Fe/Co moments undergo a spin reorientation to Γ3(Gx, Ay, Fz). The refined magnetic moment of (Fe/Co) is 1.47(4) µ B at 7 K. The antiferromagnetic structure found experimentally is supported through the DFT calculations which predict an insulating electronic state in Dy2FeCoO6.

2.
JPRAS Open ; 19: 50-55, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32158852

RESUMO

INTRODUCTION: A 22-day-old male infant presented with complete bilateral cleft lip and palate with prominent premaxillary segment, wide alar base, flat alar domes and no columellar tissue, thus leading to a severe facial deformity. A presurgical nasoalveolar moulding (PNAM) procedure was planned to facilitate an optimal surgical approximation of the cleft and surrounding tissues. METHODS: PNAM was performed on the basis of the hypothesis that 'The palatal shelves continue to grow unabated if adequate relief is provided by wax mock up while preparing the feeding plate'. An intraoral device, which consisted of an acrylic feeding plate, was constructed after adequate wax mock up in the cleft area for passive moulding, along with extraoral traction force through active lip taping. A nasal stent was subsequently attached to lift the nasal domes and lengthen the columella. The changes thus achieved with PNAM were assessed using innovative photographic and model analyses. RESULTS: On completion of PNAM, the qualitative photographic changes showed significant premaxillary setback, columellar lengthening and fullness of alar domes. The quantitative model analysis revealed reduction in the anteroposterior cleft gap by 5 mm and 5.5 mm on right and left sides, respectively. Transverse distance between the two palatal segments reduced by 3.5 mm, 8 mm and 8.5 mm in anterior, middle and posterior regions, respectively. CONCLUSION: Orthodontic intervention performed for 11 weeks by PNAM helped to retract the premaxilla, reduce the cleft gap, improve the arch form, approximate lip segments and distinctly lengthen the columella. Hence, it improved the morphology of the nose by correcting the flattened nasal wings. This aided the surgeon to achieve an optimal surgical repair.

3.
Ann Oncol ; 28(7): 1448-1456, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28407030

RESUMO

Intratumoral heterogeneity (ITH) has increasingly being described for multiple cancers as the root cause of therapy resistance. Recent studies have started to explore the scope of ITH in glioblastoma (GBM), a highly aggressive and fatal form of brain tumor, to explain its inevitable therapy resistance and disease relapse. In this review, we detail the emerging data that explores the extensive genetic, cellular and functional ITH present in GBM. We discuss current experimental models of human GBM recurrence and suggest harnessing new technologies (CRISPR-Cas9 screening, CyTOF, cellular barcoding, single cell analysis) to delineate GBM ITH and identify treatment-refractory cell populations, thus opening new therapeutic windows. We will also explore why current therapeutics have failed in clinical trials and how ITH can inform us on developing empiric therapies for the treatment of recurrent GBM.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Resistência a Medicamentos , Glioblastoma/tratamento farmacológico , Recidiva Local de Neoplasia , Animais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Progressão da Doença , Resistência a Medicamentos/efeitos dos fármacos , Glioblastoma/genética , Glioblastoma/metabolismo , Glioblastoma/secundário , Humanos , Resultado do Tratamento
4.
6.
Clin Radiol ; 59(4): 364-8, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15041457

RESUMO

AIM: To determine the types and rates of complications encountered by radiographers when performing double contrast barium enemas (DCBE). MATERIALS AND METHODS: Seven hundred and forty-one questionnaires were posted to radiographers who had in the last 5 years attended one of the biannual barium enema training courses. RESULTS: Of 741 questionnaires posted 407 (54.9%) were returned completed. Approximately 348,000 barium enema examinations had been performed. Fifty-nine radiographers reported 89 complications, including 13 intra-peritoneal and 11 extra-peritoneal perforations. There were five deaths (mortality 1 in 70,000). Deaths resulted from two of 24 (10%) perforations, two of 45 (5%) cardiac events and one cerebrovascular accident that occurred during an examination. CONCLUSIONS: Radiographers have been regularly performing DCBEs for almost a decade. The mortality for radiographer-performed DCBE is similar to that previously reported for radiologists, although a slightly higher rate of perforation is noted and so this is an area where radiographer training should be targeted.


Assuntos
Sulfato de Bário , Meios de Contraste , Enema/efeitos adversos , Arritmias Cardíacas/etiologia , Sulfato de Bário/efeitos adversos , Meios de Contraste/efeitos adversos , Hipersensibilidade a Drogas/etiologia , Humanos , Infarto do Miocárdio/etiologia , Peritônio/lesões , Reto/lesões , Ruptura , Inquéritos e Questionários
7.
J Immunol ; 167(3): 1609-16, 2001 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-11466383

RESUMO

The lumenal surface of the colonic epithelium is continually exposed to Gram-negative commensal bacteria and LPS. Recognition of LPS by Toll-like receptor (TLR)-4 results in proinflammatory gene expression in diverse cell types. Normally, however, commensal bacteria and their components do not elicit an inflammatory response from intestinal epithelial cells (IEC). The aim of this study is to understand the molecular mechanisms by which IEC limit chronic activation in the presence of LPS. Three IEC lines (Caco-2, T84, HT-29) were tested for their ability to activate an NF-kappaB reporter gene in response to purified, protein-free LPS. No IEC line responded to LPS, whereas human dermal microvessel endothelial cells (HMEC) did respond to LPS. IEC responded vigorously to IL-1beta in this assay, demonstrating that the IL-1 receptor signaling pathway shared by TLRs was intact. To determine the reason for LPS hyporesponsiveness in IEC, we examined the expression of TLR4 and MD-2, a critical coreceptor for TLR4 signaling. IEC expressed low levels of TLR4 compared with HMEC and none expressed MD-2. To determine whether the low level of TLR4 expression or absent MD-2 was responsible for the LPS signaling defect in IEC, the TLR4 or MD-2 gene was transiently expressed in IEC lines. Transient transfection of either gene individually was not sufficient to restore LPS signaling, but cotransfection of TLR4 and MD-2 in IEC led to synergistic activation of NF-kappaB and IL-8 reporter genes in response to LPS. We conclude that IEC limit dysregulated LPS signaling by down-regulating expression of MD-2 and TLR4. The remainder of the intracellular LPS signaling pathway is functionally intact.


Assuntos
Antígenos de Superfície/biossíntese , Regulação para Baixo/genética , Regulação para Baixo/imunologia , Proteínas de Drosophila , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Lipopolissacarídeos/farmacologia , Glicoproteínas de Membrana/biossíntese , Receptores de Superfície Celular/biossíntese , Antígenos de Superfície/fisiologia , Células CACO-2 , Linhagem Celular Transformada , Genes Reporter/imunologia , Células HT29 , Humanos , Inflamação/genética , Inflamação/imunologia , Interleucina-8/genética , Interleucina-8/metabolismo , Mucosa Intestinal/citologia , Lipopolissacarídeos/isolamento & purificação , Antígeno 96 de Linfócito , Glicoproteínas de Membrana/fisiologia , NF-kappa B/genética , NF-kappa B/metabolismo , Receptores de Superfície Celular/fisiologia , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Receptor 4 Toll-Like , Receptores Toll-Like , Transfecção
8.
IEEE Trans Image Process ; 10(2): 307-16, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-18249621

RESUMO

This paper describes the design and performance of an image capture simulator. The general model underlying the simulator assumes that the image capture device contains multiple classes of sensors with different spectral sensitivities and that each sensor responds in a known way to irradiance over most of its operating range. The input to the simulator is a set of narrow-band images of the scene taken with a custom-designed hyperspectral camera system. The parameters for the simulator are the number of sensor classes, the sensor spectral sensitivities, the noise statistics and number of quantization levels for each sensor class, the spatial arrangement of the sensors and the exposure duration. The output of the simulator is the raw image data that would have been acquired by the simulated image capture device. To test the simulator, we acquired images of the same scene both with the hyperspectral camera and with a calibrated Kodak DCS-200 digital color camera. We used the simulator to predict the DCS-200 output from the hyperspectral data. The agreement between simulated and acquired images validated the image capture response model and our simulator implementation. We believe the simulator will provide a useful tool for understanding the effect of varying the design parameters of an image capture device.

9.
IEEE Trans Image Process ; 10(4): 632-42, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-18249652

RESUMO

We formalize ideas of orthogonality and inner products implicit in the development of a number of figures of merit (FOM) of color recording filters. We show that, in negligible measurement noise, the data dependence of each FOM based on linear color correction is equivalent to a choice of inner product (and hence of orthogonality). Further, we show that optimal sensors with respect to noise sensitivity are simply defined as orthogonal with respect to this inner product. We also develop the idea of a generalized Q-factor by generalizing the Euclidean inner product to include all inner products. Simulations demonstrate the utility of our analytical results.

10.
IEEE Trans Image Process ; 6(2): 312-20, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-18282925

RESUMO

The problem of the design of color scanning filters is addressed in this paper. The problem is posed within the framework of the vector space approach to color systems. The measure of the goodness of a set of color scanning filters presented in earlier work is used as an optimization criterion to design color scanning filters modeled in terms of known, smooth, nonnegative functions. The best filters are then trimmed using the gradient of the mean square DeltaE(ab) error to obtain filters with a lower value of perceptual error. The results obtained demonstrate the utility of the method.

11.
IEEE Trans Image Process ; 6(2): 321-7, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-18282926

RESUMO

The problem of the sensitivity analysis of color scanning filters is addressed in this paper. The second differential of the mean square DeltaE(ab) error provides a means of calculating the sensitivity of the mean square DeltaE(ab) error to filter fabrication errors. Tolerances on the allowable change in the mean square DeltaE(ab) error are used to define bounds on the filter fabrication errors at all wavelengths and at single wavelengths.

12.
J Postgrad Med ; 42(4): 105-8, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-9715310

RESUMO

Picrorhiza kurroa (Pk), a known hepatoprotective plant, was studied in experimental and clinical situtations. The standardization of active principles--Picroside 1 and 2 was done with High Performance Liquid Chromatography. Picroside 1 ranged from 2.72 to 2.88 mg/capsule and picroside 2 from 5.50 to 6.00 mg/capsule. In the galactosamine-induced liver injury in rats, Pk at a dose of 200 mg/kg p.o. showed a significant reduction (p < 0.05) in liver lipid content, GOT and GPT. In a randomised, double-blind placebo controlled trial in patients diagnosed to have acute viral hepatitis (HBsAg negative), Pk root powder 375 mg three times a day was given for 2 weeks (n = 15) or a matching placebo (n = 18) was given. Difference in values of bilirubin, SGOT and SGPT was significant between placebo and Pk groups. The time in days required for total serum bilirubin to drop to average value of 2.5 mg% was 75.9 days in placebo as against 27.44 days in Pk group. The present study has shown a biological plausability of efficacy of Pk as supported by clinical trial in viral hepatitis, hepatoprotection in animal model and an approach for standardizing extracts based on picroside content.


Assuntos
Cinamatos/uso terapêutico , Glicosídeos/uso terapêutico , Hepatite Viral Humana/tratamento farmacológico , Hepatopatias/tratamento farmacológico , Ayurveda , Ácido Vanílico/uso terapêutico , Doença Aguda , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Bilirrubina/sangue , Cinamatos/química , Modelos Animais de Doenças , Método Duplo-Cego , Avaliação Pré-Clínica de Medicamentos , Glicosídeos/química , Hepatite Viral Humana/metabolismo , Humanos , Hepatopatias/metabolismo , Masculino , Distribuição Aleatória , Ratos , Ácido Vanílico/química
13.
Appl Ergon ; 23(6): 414-24, 1992 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15676886

RESUMO

In this paper, we present an application of engineering and ergonomics principles in the design of an optical disk handling tool for use in a cleanroom environment. A qualitative model which considers the task, operator, machines and environment (TOME model) was utilized to guide the design process. A 'before-after' evaluation found a significant improvement in the proposed tool over the existing tool with respect to mechanical, biomechanical and subjective measures. Product yield has improved considerably, as measured after the implementation of the proposed tool in December 1989 until the end of the observation period in June 1991.

14.
Appl Opt ; 26(12): 2297-8, 1987 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-20489864
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