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1.
Chem Sci ; 14(27): 7559-7563, 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37449061

RESUMO

Candida auris (C. auris) is an emerging multidrug-resistant fungal pathogen that represents a significant public health challenge as it can spread rapidly and result in high mortality rates. The mannans on the C. auris cell surface are potent immunogens and attractive targets for developing a glycoconjugate vaccine. We synthesized the oligosaccharides resembling cell surface mannans of C. auris and printed them onto microarray slides that were used to screen plasma from mice infected with C. auris. IgM antibodies in mouse plasma recognize the ß-1,2 linkage present in C. auris surface mannans. Disaccharide 19 emerged from glycan array screening as a lead for developing a vaccine against C. auris, as the majority of patient plasma samples showed antibodies against this glycan. The synthetic oligosaccharides can be used for the early detection of C. auris infections.

3.
Plasmonics ; 18(2): 577-585, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36712825

RESUMO

Coronavirus disease (COVID-19) is a worldwide health emergency caused by the coronavirus 2 (severe acute respiratory illness) (SARS-CoV-2). COVID-19 has a wide range of symptoms, making a definitive diagnosis difficult. The shortage of equipment for testing technology COVID-19 has resulted in long queues for COVID-19 testing, which is a major problem. COVID-19 testing is currently performed using sluggish and costly technology like single-photon emission computed tomography (SPECT), computed tomography (CT), positron emission tomography (PET), and enzyme-linked immunosorbent assay (ELISA). The gold standard test for diagnosing COVID-19 is real-time reverse transcriptase-polymerase chain reaction (RT-PCR), which necessitates highly skilled workers and has a lengthy turnaround time. However, rapid and affordable immunodiagnostic techniques (antigen or antibody tests) are also available with some trade off accuracy. Optical sensors are frequently employed in a variety of applications, because of their increased sensitivity, strong selectivity, rapid reaction times, and outstanding resolution. The use of photonic crystal fibre (PCF) is advantageous for the quick detection of the new coronavirus and is suggested with the use of a PCF-based (Au/BaTiO3/graphene) multilayered surface plasmon resonance (SPR) biosensor. The proposed sensor can quickly detect the COVID-19 virus in two different ligand-analyte environments: (i) the virus spike receptor-binding domain (RBD) as an analyte and monoclonal antibodies (mAbs) as a probe ligand, and (ii) monoclonal antibodies (IgG or IgM) as an analyte and the virus spike RBD as a probe ligand. The finite element method (FEM) is used to quantitatively examine the performance of the PCF-based multilayered SPR sensor.

4.
J Indian Assoc Pediatr Surg ; 28(6): 529-531, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38173636

RESUMO

A 5-day-old male presented with bilious vomiting, a grossly distended abdomen, and passage of a small amount of stool. The anal opening was at a normal position. X-ray abdomen showed a large bowel loop with a single air-fluid level occupying more than half of the abdominal width. On laparotomy, the ascending colon was dilated to form a pouch-like structure, and the ileum and appendix were opening into it. Colon distal to pouch was present as microcolon. Histopathology of the dilated segment was suggestive of congenital segmental dilatation (CSD). In CSD, the distal bowel is of normal caliber. This is a rare case of CSD of ascending colon with distal microcolon.

5.
Org Lett ; 24(12): 2371-2375, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35311265

RESUMO

Here we report the first total synthesis of several oligosaccharides resembling the capsular polysaccharide of swine pathogen S. suis serotype 18 repeating unit [→3)-d-GalNAc(α1-3)[d-Glc(ß1-2)]-d-GalA4OAc(ß1-3)-d-GalNAc(α1-3)-d-BacNAc4NAc(α1→]n. Access to the pentasaccharide repeating unit antigen proved to be very challenging due to the poor reactivity in the context of the trisaccharide. The challenge was overcome by the creation of a galacturonic acid in a late stage of the synthesis.


Assuntos
Streptococcus suis , Animais , Sequência de Carboidratos , Glicoconjugados , Oligossacarídeos , Polissacarídeos Bacterianos , Sorogrupo , Suínos , Desenvolvimento de Vacinas
6.
J Org Chem ; 86(15): 10838-10851, 2021 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-34291945

RESUMO

Biaryl and indole units are important structural motifs in several bioactive molecules and functional materials. We have accomplished straightforward access to C2-biarylated indole derivatives through palladium-catalyzed C-H activation strategy with a broad range of substrate scope in yields of 24 to 92%. Besides, the UV/visible absorption and fluorescence properties of the ensuing products were explored. The calculated higher dihedral angle and rotational barrier values for the selected C2-biarylated indoles show that these compounds may display atropisomerism at room temperature.


Assuntos
Indóis , Paládio , Catálise , Fluorescência
7.
Org Biomol Chem ; 18(17): 3354-3359, 2020 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-32307478

RESUMO

1,1,2-Triarylethanes embedded with an azaarene unit were prepared in a single step at ambient temperature via the sodium hexamethyldisilazide mediated 1,6-conjugate addition of unactivated alkylazaarenes on para-quinone methides (p-QMs). The extent of this methodology was investigated with a wide range of p-QMs and alkylazaarenes, and the respective products were obtained in moderate to excellent yields. The regioselective 1,6-conjugate addition of the trialkylazaarene precursor on para-quinone methide was also presented. Besides, we showcased the direct synthesis of the 1,1,2-triarylethane derivative from aldehyde via the in situ generation of para-quinone methide.

8.
J Minim Access Surg ; 16(2): 182-184, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31031318

RESUMO

Diaphragmatic hernia is protrusion of the abdominal contents into the thoracic cavity. It is a congenital defect of the diaphragm. It is most commonly encountered in infancy but rarely in adults. Here, we would like to present a rare case of 75-year-old male with Bochdalek's hernia. The patient had presented for the first time in his life for his symptoms. This case report emphasises the rare presentation of Bochdalek's hernia in an elderly male. The patient was treated using minimal access surgery i.e., laparoscopic approach and hence had a better post-operative outcome.

9.
IEEE Trans Image Process ; 25(9): 4018-32, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27295674

RESUMO

Local binary pattern (LBP) is widely adopted for efficient image feature description and simplicity. To describe the color images, it is required to combine the LBPs from each channel of the image. The traditional way of binary combination is to simply concatenate the LBPs from each channel, but it increases the dimensionality of the pattern. In order to cope with this problem, this paper proposes a novel method for image description with multichannel decoded LBPs. We introduce adder- and decoder-based two schemas for the combination of the LBPs from more than one channel. Image retrieval experiments are performed to observe the effectiveness of the proposed approaches and compared with the existing ways of multichannel techniques. The experiments are performed over 12 benchmark natural scene and color texture image databases, such as Corel-1k, MIT-VisTex, USPTex, Colored Brodatz, and so on. It is observed that the introduced multichannel adder- and decoder-based LBPs significantly improve the retrieval performance over each database and outperform the other multichannel-based approaches in terms of the average retrieval precision and average retrieval rate.

10.
IEEE Trans Image Process ; 24(12): 5892-903, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26513789

RESUMO

A new image feature description based on the local wavelet pattern (LWP) is proposed in this paper to characterize the medical computer tomography (CT) images for content-based CT image retrieval. In the proposed work, the LWP is derived for each pixel of the CT image by utilizing the relationship of center pixel with the local neighboring information. In contrast to the local binary pattern that only considers the relationship between a center pixel and its neighboring pixels, the presented approach first utilizes the relationship among the neighboring pixels using local wavelet decomposition, and finally considers its relationship with the center pixel. A center pixel transformation scheme is introduced to match the range of center value with the range of local wavelet decomposed values. Moreover, the introduced local wavelet decomposition scheme is centrally symmetric and suitable for CT images. The novelty of this paper lies in the following two ways: 1) encoding local neighboring information with local wavelet decomposition and 2) computing LWP using local wavelet decomposed values and transformed center pixel values. We tested the performance of our method over three CT image databases in terms of the precision and recall. We also compared the proposed LWP descriptor with the other state-of-the-art local image descriptors, and the experimental results suggest that the proposed method outperforms other methods for CT image retrieval.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Análise de Ondaletas , Encéfalo/diagnóstico por imagem , Bases de Dados Factuais , Humanos , Radiografia Torácica
11.
IEEE Trans Image Process ; 23(12): 5323-33, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25248185

RESUMO

The region descriptors using local intensity ordering patterns have become more popular recent years for image matching due to its enhanced discriminative ability. However, the dimension of these descriptors increases rapidly with the slight increase in the number of local neighbors under consideration and becomes unreasonable for image matching due to time constraint. In this paper, we reduce the dimension of the descriptor and matching time significantly while keeping up the comparable performance by considering the number of neighboring sample points in an interleaved manner. The proposed interleaved order based local descriptor (IOLD) considers the local neighbors of a pixel as a set of interleaved neighbors and constructs the descriptor over each set separately and finally combines them to produce a single pattern. We extract the local ordering pattern to cope up with the illumination effect in an inherent rotation invariant manner. The novelty lies with using multiple neighboring sets in an interleaved fashion. We also explored the local intensity order pattern in a multisupport-region scenario. Results are compared over three challenging and widely adopted image matching data sets with other prominent descriptors under various image transformations. Results based on experiments suggest that the proposed IOLD descriptor outperforms in terms of both improved matching performance and reduced matching time. We also found that the amount of improvement is significant under complex illumination difference while showing more robustness toward noise.

12.
Int J Clin Pediatr Dent ; 3(3): 147-52, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-27616836

RESUMO

The cytotoxicity of a resin-based material can be evaluated on isolated human lymphocyte. Since resin-based dental materials have been used with increasing frequency in anterior and posterior teeth restorations, the uncured resin monomers are leached out from the restorations and diffuses into the dentine and ultimately hampers the odontoblastic layers of pulp as well as gingiva. It is also reaches into the saliva and circulatory blood. The study evaluates and compares the relative cytotoxicity of resin-based dental materials at different time interval, i.e. 24, 48, and 72 hours on human lymphocyte by Trypan blue exclusion method. All resins were found to be cytotoxic to human lymphocyte. Resin samples cytotoxicity was the highest in first 24 hours followed by 48 and 72 hours.

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