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1.
Heliyon ; 10(19): e37502, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39386811

RESUMO

T follicular helper cells (Tfh) were initially identified nearly two decades ago as critically important in directing B-cell maturation and antibody generation in the germinal centers of secondary lymphoid tissues. Since then, Tfh cells have become the center of sustained investigation in oncology due to their unique, often paradoxical roles in tumour immunity. Specifically, Tfh cells in the tumour microenvironment can enhance anti-tumour immune response or promote, through the same mechanisms, tumour progression. These dual roles largely result from Tfh cells controlling unique cytokine secretions and, in turn, shifting the net effect of the Tfh-driven immune response (by directly and indirectly affecting the activities of other cytotoxic T cells and natural killer cells). The dual nature of the Tfh is the basis for our commentary, which highlights their simultaneous identity as a curse and a gift to oncology. Indeed, the curtain calls for a better understanding Tfh cell biology, so that their potential can be used to benefit oncology. We discuss how prevalent Tfh cells in tumors can be beneficial in directing potent anti-tumour immune responses. We also review how the characterization of Tfh cells in tumors has now led to their identification as candidate biomarkers of response to immunotherapy, and how they are now being evaluated as targets for new immunotherapies leading to new clinical trials. The study concludes by emphasizing how the unique biological properties of Tfh cells can be leveraged to advance cancer treatment, ultimately aiming to enhance the effectiveness of clinical oncology practices.

2.
Heliyon ; 10(16): e34407, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39253236

RESUMO

In the realm of modern healthcare, Electronic Health Records EHR serve as invaluable assets, yet they also pose significant security challenges. The absence of EHR access auditing mechanisms, which includes the EHR audit trails, results in accountability gaps and magnifies security vulnerabilities. This situation effectively paves the way for unauthorized data alterations to occur without detection or consequences. Inadequate EHR compliance auditing procedures, particularly in verifying and validating access control policies, expose healthcare organizations to risks such as data breaches, and unauthorized data usage. These vulnerabilities result from unchecked unauthorized access activities. Additionally, the absence of EHR audit logs complicates investigations, weakens proactive security measures, and raises concerns to put healthcare institutions at risk. This study addresses the pressing need for robust EHR auditing systems designed to scrutinize access to EHR data, encompassing who accesses it, when, and for what purpose. Our research delves into the complex field of EHR auditing, which includes establishing an immutable audit trail to enhance data security through blockchain technology. We also integrate Purpose-Based Access Control (PBAC) alongside smart contracts to strengthen compliance auditing by validating access legitimacy and reducing unauthorized entries. Our contributions encompass the creation of audit trail of EHR access, compliance auditing via PBAC policy verification, the generation of audit logs, and the derivation of data-driven insights, fortifying EHR access security.

3.
PLoS One ; 18(9): e0291429, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37768962

RESUMO

Novel hardware architectures for dynamic reconfigurable implementation of 64-bit MISTY1 and KASUMI block ciphers are proposed to enhance the performance of cryptographic chips for secure IoT applications. The SRL32 primitive (Reconfigurable Look up Tables-RLUTs) and DPR (Dynamic Partial Reconfiguration) are employed to reconfigure single round MISTY1 / KASUMI algorithms on the run-time. The RLUT based architecture attains dynamic logic functionality without extra hardware resources by internally modifying the LUT contents. The proposed adaptive reconfiguration can be adopted as a productive countermeasure against malicious attacks with the added advantage of less reconfiguration time (RT). On the other hand, the block architecture reconfigures the core hardware by externally uploading the partial bit stream and has significant advantages in terms of low area implementation and power reduction. Implementation was carried out on FPGA, Xilinx Virtex 7. The results showed remarkable results with very low area of 668 / 514 CLB slices consuming 460 / 354 mW for RLUT and DPR architectures respectively. Moreover, the throughput obtained for RLUT architecture was found as 364 Mbps with very less RT of 445 nsec while DPR architecture achieved speed of 176 Mbps with RT of 1.1 msec. The novel architectures outperform the stand-alone existing hardware designs of MISTY1 and KASUMI implementations by adding the dynamic reconfigurability while at the same achieving high performance in terms of area and throughput. Design details of proposed unified architectures and comprehensive analysis is described.

4.
Micromachines (Basel) ; 14(2)2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36838163

RESUMO

This manuscript examines the design principle and real-world validation of a new miniaturized high-performance flower-shaped radiator (FSR). The antenna prototype consists of an ultracompact square metallic patch of 0.116λ0 × 0.116λ0 (λ0 is the free space wavelength at 3.67 GHz), a rectangular microstrip feed network, and a partial metal ground plane. A novel, effective, and efficient approach based on open circuit loaded stubs is employed to achieve the antenna's optimal performance features. Rectangular, triangular, and circular disc stubs were added to the simple structure of the square radiator, and hence, the FSR configuration was formed. The proposed antenna was imprinted on a low-cost F4B laminate with low profile thickness of 0.018λ0, relative permittivity εr = 2.55, and dielectric loss tangent δ = 0.0018. The designed radiator has an overall small size of 0.256λ0 × 0.354λ0. The parameter study of multiple variables and their influence on the performance results has been extensively studied. Moreover, the impact of different substrate materials, impedance bandwidths, resonance tuning, and impedance matching has also been analyzed. The proposed antenna model has been designed, simulated, and fabricated. The designed antenna exhibits a wide bandwidth of 5.33 GHz ranging from 3.67 to 9.0 GHz at 10 dB return loss, which resulted in an 83.6% fractional impedance bandwidth; a maximum gain of 7.3 dBi at 8.625 GHz; optimal radiation efficiency of 89% at 4.5 GHz; strong intensity current flow across the radiator; and stable monopole-like far-field radiation patterns. Finally, a comparison between the scientific results and newly published research has been provided. The antenna's high-performance simulated and measured results are in a good agreement; hence, they make the proposed antenna an excellent choice for modern smartphones' connectivity with the sub-6 GHz frequency spectrum of modern fifth-generation (5G) mobile communication application.

5.
Brain Topogr ; 35(4): 507-524, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35072833

RESUMO

With the recent advancement in computer technology, we can extract the picture of the brain as a network. The aim of this study is to constructs large scale individual anatomical brain networks using regional gray matter cortical thickness from individual subject's magnetic resonance imaging (MRI) data, as well as to investigate changes with normal aging in global network organization. The dataset includes 183 healthy subjects sMRI data with an age range from 50 to 80 plus. For all brain networks, we calculated the global network measures and nodal network measures by using network analysis toolkit GRETNA. From global network measurements we calculated small-world measurements and network efficiency measurements, from nodal measurements we calculated node clustering coefficient (CC) and node efficiency at a wide-range of threshold values. All small world measurements showed more clustering at all the given threshold values than random networks and a alike least path length, indicative of that they were "small world". To analyze the effect normal ageing on networks organization, the networks of subjects were categorized into three age groups (50s, 60s, and 70 over). The global and nodal network measurements of each group were statistically analyzed to investigate the significant difference in network organization with in age groups. Results shows that the age has no significance effect in global measurements of brain network. However, by analysis the nodal measures of brain network between age group, network nodes from brain frontal lobe and temporal lobe showed age related significant difference. The results obtained from the proposed study suggest that this network method can deliver a concise network-level picture of brain organization and be used from the outlook of composite networks to investigate inter-individual variability in brain morphology.


Assuntos
Encéfalo , Imageamento por Ressonância Magnética , Idoso , Envelhecimento , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Análise por Conglomerados , Humanos , Imageamento por Ressonância Magnética/métodos , Rede Nervosa/diagnóstico por imagem
6.
PeerJ Comput Sci ; 7: e709, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34616889

RESUMO

With the recent development in network technology over a few years, digital works can be easily published online. One of the main issues in the field of digital technology is the infringement of digital works, which can seriously damage the data owners' rights and affects the enthusiasm of the owners to create original work. Thus, more attention is required for the protection of digital copyright as it has a great impact on the development of society. Many digital copyright protection techniques were developed in the past, but still, there are many loopholes in the protection systems to be covered. The protection means are still relatively weak, timeliness is poor, infringement is frequent, a right determination is cumbersome, and the results are not ideal. Aiming at the mentioned problems, this paper proposes a protection technique, which can realize the automatic management of the complete digital rights life cycle on the blockchain using fabric's smart contract technology. The proposed system is based on blockchain technology, which leverages the distributed, tamper-proof and traceable characteristics of blockchain. The system uses smart contracts to manage the full life cycle of digital copyright. The test results show that the proposed system provides effective protection of the digital copyright system and can efficiently confirm the rights of digital copyright.

7.
J Matern Fetal Neonatal Med ; 32(16): 2667-2673, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29478349

RESUMO

OBJECTIVE: To audit the demand and radiation exposure of conventional radiography in a regional neonatal intensive care unit (NICU) in Ireland. METHODS: A retrospective study of radiographs performed on all admissions to the NICU in University Maternity Hospital Limerick (UMHL) over 2 years. RESULTS: A total of 1405 radiographs were performed on 506 infants. 153.5 radiographs per 1000 live births was the observed demand and 44% of radiographs were done out of hours. 47% of all radiographs were performed on infants <1500 g. Median number of radiographs per infant was one (IQR 1-2; range 1-39). Significant negative correlation was observed between number of radiographs and gestational age. Mean lung radiation doses estimated using published values for normal weight (>2500 g), very low birth weight (VLBW), and extremely low birth weight (ELBW) infants based on the median number of chest X-rays were 31.7 µGym, 84.66 and 232.75 µGy, respectively. CONCLUSIONS: Conventional radiography remains a key diagnostic tool in neonatology particularly in VLBW and ELBW infants and is invaluable in supporting timely clinical decision making. Clinicians should be aware of the cost and potential hazards of neonatal radiography and is recommend that the cumulative radiation exposure among the ELBW and VLBW infants is monitored. Increasing awareness and standardisation of point-of-care ultrasonography could decrease the reliance on conventional radiography in neonatal units.


Assuntos
Doenças do Prematuro/diagnóstico , Unidades de Terapia Intensiva Neonatal/estatística & dados numéricos , Radiografia/estatística & dados numéricos , Idade Gestacional , Humanos , Recém-Nascido de Peso Extremamente Baixo ao Nascer , Recém-Nascido , Doenças do Prematuro/epidemiologia , Irlanda/epidemiologia , Radiografia/economia , Estudos Retrospectivos
8.
J Microsc ; 268(2): 141-154, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28613391

RESUMO

The development of genetically engineered mouse models for neuronal diseases and behavioural disorders have generated a growing need for small animal imaging. High-resolution magnetic resonance microscopy (MRM) provides powerful capabilities for noninvasive studies of mouse brains, while avoiding some limits associated with the histological procedures. Quantitative comparison of structural images is a critical step in brain imaging analysis, which highly relies on the performance of image registration techniques. Nowadays, there is a mushrooming growth of human brain registration algorithms, while fine-tuning of those algorithms for mouse brain MRMs is rarely addressed. Because of their topology preservation property and outstanding performance in human studies, diffeomorphic transformations have become popular in computational anatomy. In this study, we specially tuned five diffeomorphic image registration algorithms [DARTEL, geodesic shooting, diffeo-demons, SyN (Greedy-SyN and geodesic-SyN)] for mouse brain MRMs and evaluated their performance using three measures [volume overlap percentage (VOP), residual intensity error (RIE) and surface concordance ratio (SCR)]. Geodesic-SyN performed significantly better than the other methods according to all three different measures. These findings are important for the studies on structural brain changes that may occur in wild-type and transgenic mouse brains.


Assuntos
Encéfalo/anatomia & histologia , Encéfalo/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Microscopia/métodos , Algoritmos , Animais , Encéfalo/fisiologia , Camundongos
9.
Eur J Pharmacol ; 691(1-3): 292-6, 2012 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-22819704

RESUMO

Exenatide or Exendin-4 is a 39-amino acid agonist of the glucagon like peptide (GLP-1) receptor approved for the adjunctive treatment for type 2 diabetes. Recent reports suggest that GLP-1 agonists may also have distant effects including C-cell thyroid hyperplasia. The aim of this study was to evaluate the effect of exendin-4 on the thyroid and parathyroid cells in a rat model. Rat thyroids were stained for calcitonin, H&E and for carcinoembryonic antigen (CEA). Thyroid C-cell hyperplasia was graded on H&E stained slides using cell size and secretory granule numbers, morphological features of the parathyroid glands and the serum calcium concentrations of the rats were also evaluated. Counts of stained cells/high power field and intensity of staining were recorded by two pathologists. Data were analyzed by ANOVA/post-tests. C cell hypertrophy was elevated in exenatide-treated vs. untreated animals (22.5 ± 8.7 vs. 10.5 ± 2.7 cells/HPF). CEA staining failed to show effects by exendin. Calcitonin staining was significantly elevated in exenatide treated controls (P<0.001). Parathyroid glands were histologically normal in both groups, and serum calcium levels were within normal range in all animals. In summary, exenatide was associated with C cell hyperplasia and increased calcitonin staining of thyroids, but was unrelated to CEA levels. These data raise important concerns about the effects of exenatide which, given its wide clinical use, should be clarified with urgency.


Assuntos
Glândulas Paratireoides/efeitos dos fármacos , Glândulas Paratireoides/metabolismo , Peptídeos/farmacologia , Receptores de Glucagon/agonistas , Glândula Tireoide/efeitos dos fármacos , Glândula Tireoide/metabolismo , Peçonhas/farmacologia , Animais , Calcitonina/metabolismo , Cálcio/sangue , Antígeno Carcinoembrionário/metabolismo , Exenatida , Receptor do Peptídeo Semelhante ao Glucagon 1 , Masculino , Ratos , Ratos Sprague-Dawley
10.
J Endourol ; 17(7): 475-9; discussion 479, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-14565877

RESUMO

Persistent urachus is a rare congenital anomaly. Various types of remnants have been described including cyst, alternating sinus, patent urachus, diverticulum, and sinus. The most common presenting symptom of urachal sinus is umbilical discharge. Radical excision of the remnant, with or without a bladder cuff, is essential to prevent future malignant degeneration or recurrence of the remnant. Although open surgical excision has been the treatment of choice for many years, the laparoscopic approach has become an attractive alternative because of its association with less postoperative pain, better cosmesis, and rapid convalescence. Laparoscopic radical excision of a urachal sinus was performed in a 16-year-old female patient who presented with umbilical discharge.


Assuntos
Laparoscopia/métodos , Cisto do Úraco/cirurgia , Procedimentos Cirúrgicos Urológicos/métodos , Adolescente , Feminino , Humanos , Tomografia Computadorizada por Raios X , Cisto do Úraco/diagnóstico por imagem
11.
Diagn Cytopathol ; 29(4): 200-2, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14506671

RESUMO

A review of the literature noted 11-16% discrepancy rates in cytology and histology diagnoses. We collected 358 cases with abnormal cytology and matching cervical biopsies. There were 123 (30%) discrepant pairs, of which 34 (27%) had negative biopsies following Papanicolaou (Pap) smears with squamous intraepithelial lesions (SIL). These constituted our study group. All biopsies were obtained within an average of 5 wk after Pap smears (range, 0-18 wk). After confirming original diagnoses, all biopsies were evaluated for the presence of squamocolumnar junction, proper orientation, gross size of specimen, denudation of superficial mucosa, and inadequate sectioning through blocks. Each block was recut at three levels and reviewed microscopically. Five biopsies (14%) needed reorientation. Nine biopsies (26%) showed more than a 2-mm difference from gross size. Eleven (32%) new SILs were found. Adequate deep sectioning and proper orientation of tissues can significantly improve cytohistologic correlations.


Assuntos
Biópsia/métodos , Teste de Papanicolaou , Displasia do Colo do Útero/patologia , Neoplasias do Colo do Útero/patologia , Esfregaço Vaginal/métodos , Reações Falso-Negativas , Feminino , Seguimentos , Humanos , Reprodutibilidade dos Testes , Esfregaço Vaginal/normas
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