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1.
Clin Infect Dis ; 72(5): e120-e127, 2021 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-33515460

RESUMEN

BACKGROUND: The emergence and spread of antimicrobial resistance (AMR) pose a major threat to the effective treatment and control of typhoid fever. The ongoing outbreak of extensively drug-resistant Salmonella Typhi (S. Typhi) in Pakistan has left azithromycin as the only remaining broadly efficacious oral antimicrobial for typhoid in South Asia. Ominously, azithromycin-resistant S. Typhi organisms have been subsequently reported in Bangladesh, Pakistan, and Nepal. METHODS: Here, we aimed to understand the molecular basis of AMR in 66 S. Typhi organisms isolated in a cross-sectional study performed in a suburb of Chandigarh in Northern India using whole-genome sequencing and phylogenetic analysis. RESULTS: We identified 7 S. Typhi organisms with the R717Q mutation in the acrB gene that was recently found to confer resistance to azithromycin in Bangladesh. Six out of the seven azithromycin-resistant S. Typhi isolates also exhibited triple mutations in gyrA (S83F and D87N) and parC (S80I) genes and were resistant to ciprofloxacin. These contemporary ciprofloxacin/azithromycin-resistant isolates were phylogenetically distinct from each other and from those reported from Bangladesh, Pakistan, and Nepal. CONCLUSIONS: The independent emergence of azithromycin-resistant typhoid in Northern India reflects an emerging broader problem across South Asia and illustrates the urgent need for the introduction of typhoid conjugate vaccines in the region.


Asunto(s)
Salmonella typhi , Fiebre Tifoidea , Antibacterianos/farmacología , Azitromicina/farmacología , Bangladesh/epidemiología , Estudios Transversales , Farmacorresistencia Bacteriana , Genotipo , Humanos , India/epidemiología , Pruebas de Sensibilidad Microbiana , Nepal , Pakistán , Filogenia , Salmonella typhi/genética , Fiebre Tifoidea/epidemiología
2.
Biochemistry ; 55(42): 5938-5946, 2016 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-27700064

RESUMEN

Activation of protein kinase C (PKC), a serine/threonine protein kinase, ubiquitously influences cellular signal transduction and has been shown to play a role in viral entry. In this study, we explored a role for PKC in human adenovirus type 37 infection of primary human corneal fibroblasts, a major target cell for infection. We sought evidence for an interaction between PKC activation and two potential downstream targets: cSrc kinase, shown previously to play a critical role in adenovirus signaling in these cells, and caveolin-1, reported earlier to be important to entry of adenovirus type 37. Infection of fibroblasts increased PKCα phosphorylation and translocation of PKCα from the cytosol to caveolin-1 containing vesicles. Virus-induced phosphorylation of both cSrc and AKT was abolished in cell lysates pretreated with calphostin C, a chemical inhibitor of PKC. Inhibition of PKC also reduced virus associated phosphorylation of caveolin-1, while inhibition of cSrc by the chemical inhibitor PP2 reduced only caveolin-1 phosphorylation, but not PKCα phosphorylation, in lipid rafts. These results suggest a role for PKCα upstream to both cSrc and caveolin-1. Phosphorylated PKCα was found in the same endosomal fractions as phosphorylated cSrc, and PKCα was present to a greater degree in caveolin-1 pull downs from virus infected than mock infected cell lysates. Calphostin C also reduced early viral gene expression, indicating that PKCα activity may be required for viral entry. PKCα plays a central role in adenovirus infection of corneal fibroblasts and regulation of downstream molecules, including the important lipid raft component caveolin-1.

3.
J Neurochem ; 138(2): 317-27, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-26998748

RESUMEN

Traumatic brain injury (TBI) is associated with adverse effects on brain functions, including sensation, language, emotions and/or cognition. Therapies for improving outcomes following TBI are limited. A better understanding of the pathophysiological mechanisms of TBI may suggest novel treatment strategies to facilitate recovery and improve treatment outcome. Aberrant activation of cyclin-dependent kinase 5 (Cdk5) has been implicated in neuronal injury and neurodegeneration. Cdk5 is a neuronal protein kinase activated via interaction with its cofactor p35 that regulates numerous neuronal functions, including synaptic remodeling and cognition. However, conversion of p35 to p25 via Ca(2+) -dependent activation of calpain results in an aberrantly active Cdk5/p25 complex that is associated with neuronal damage and cell death. Here, we show that mice subjected to controlled cortical impact (CCI), a well-established experimental TBI model, exhibit increased p25 levels and consistently elevated Cdk5-dependent phosphorylation of microtubule-associated protein tau and retinoblastoma (Rb) protein in hippocampal lysates. Moreover, CCI-induced neuroinflammation as indicated by increased astrocytic activation and number of reactive microglia. Brain-wide conditional Cdk5 knockout mice (Cdk5 cKO) subjected to CCI exhibited significantly reduced edema, ventricular dilation, and injury area. Finally, neurophysiological recordings revealed that CCI attenuated excitatory post-synaptic potential field responses in the hippocampal CA3-CA1 pathway 24 h after injury. This neurophysiological deficit was attenuated in Cdk5 cKO mice. Thus, TBI induces increased levels of p25 generation and aberrant Cdk5 activity, which contributes to pathophysiological processes underlying TBI progression. Hence, selectively preventing aberrant Cdk5 activity may be an effective acute strategy to improve recovery from TBI. Traumatic brain injury (TBI) increases astrogliosis and microglial activation. Moreover, TBI deregulates Ca(2+) -homeostasis triggering p25 production. The protein kinase Cdk5 is aberrantly activated by p25 leading to phosphorylation of substrates including tau and Rb protein. Loss of Cdk5 attenuates TBI lesion size, indicating that Cdk5 is a critical player in TBI pathogenesis and thus may be a suitable therapeutic target for TBI.


Asunto(s)
Lesiones Traumáticas del Encéfalo/metabolismo , Encéfalo/metabolismo , Quinasa 5 Dependiente de la Ciclina/metabolismo , Neuronas/metabolismo , Animales , Calpaína/metabolismo , Modelos Animales de Enfermedad , Masculino , Ratones Endogámicos C57BL , Proteínas del Tejido Nervioso/metabolismo , Proteínas tau/metabolismo
4.
Pak J Pharm Sci ; 27(5): 1287-94, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25176364

RESUMEN

(99m)Tc labeled N-N-ethylene-L, L-dicysteine (EC) was introduced in form of multiple-step kit as an alternate renal imaging radiopharmaceutical for commonly used (99m)Tc-MAG3. We developed a single component lyophilized kit of EC ready to be labeled with (99m)Tc. We present the optimization of the components of our formulation, its evaluation in animal models, normal human volunteers and patients of various renal diseases, in comparison with (99m)Tc-MAG3. Efficient labeling of EC was achieved with our preparation at pH 7 to 12. The formulation at pH 8 was used further for bio distribution studies in organs of sacrificed Sprague Dawley rats and a live rhesus monkey using scintigraphy. After satisfactory bio-distribution results, the kit was then evaluated in normal human volunteers through renography. But the renogram parameters of (99m)Tc-EC (pH 8) were statistically inferior to (99m)Tc-MAG3. Surrogate kit at pH 10 was therefore developed and re-evaluated in rats for organ bio distribution. After favorable results the kit was then assessed further in normal volunteers and a group of patients with various renal disorders via scintigraphy. The EC kit developed at pH 10 gave images better than and scintigraphic parameters comparable to (99m)Tc-MAG3. It was concluded that single vial kit we formulated easy to prepare than three-vial kit and can be used as an alternate to (99m)Tc-MAG3.


Asunto(s)
Cisteína/análogos & derivados , Riñón/diagnóstico por imagen , Radiofármacos , Tecnecio , Animales , Química Farmacéutica , Liofilización , Concentración de Iones de Hidrógeno , Macaca mulatta , Cintigrafía , Ratas , Ratas Sprague-Dawley , Tecnecio Tc 99m Mertiatida
5.
PLoS One ; 19(6): e0305611, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38885268

RESUMEN

In this study, a simple calcination route was adopted to prepare hausmannite Mn3O4 nanoparticles using rice powder as soft bio-template. Prepared Mn3O4 was characterized by Fourier Transform Infra-Red Spectroscopy (FTIR), Field Emission Scanning Electron Microscopy (FESEM), Energy Dispersive X-ray microanalysis (EDX), Powder X-Ray Diffraction (XRD), Transmission Electron Microscopy (TEM), Brunauer-Emmett-Teller (BET) and Solid state UV-Vis spectroscopic techniques. Mn-O stretching in tetrahedral site was confirmed by FTIR and Raman spectra. % of Mn and O content supported Mn3O4 formation. The crystallinity and grain size was found to be 68.76% and 16.43 nm, respectively; tetragonal crystal system was also cleared by XRD. TEM clarified the planes of crystal formed which supported the XRD results and BET demonstrated mesoporous nature of prepared Mn3O4 having low pore volume. Low optical band gap of 3.24 eV of prepared Mn3O4 nanoparticles indicated semiconductor property and was used as cathode material to fabricate CR-2032 coin cell of Aqueous Rechargeable Zinc Ion Battery (ARZIB). A reversible cyclic voltammogram (CV) showed good zinc ion storage performance. Low cell resistance was confirmed by Electrochemical Impedance Spectroscopy (EIS). The coin cell delivered high specific discharge capacity of 240.75 mAhg-1 at 0.1 Ag-1 current density. The coulombic efficiency was found to be 99.98%. It also delivered excellent capacity retention 94.45% and 64.81% after 300 and 1000 charge-discharge cycles, respectively. This work offers a facile and cost effective approach for preparing cathode material of ARZIBs.


Asunto(s)
Suministros de Energía Eléctrica , Compuestos de Manganeso , Nanopartículas , Oryza , Óxidos , Polvos , Zinc , Oryza/química , Compuestos de Manganeso/química , Zinc/química , Óxidos/química , Nanopartículas/química , Difracción de Rayos X , Espectroscopía Infrarroja por Transformada de Fourier
6.
Heliyon ; 10(2): e24345, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38293441

RESUMEN

Natural plant based fibres are being increasingly used in sustainable fibre reinforced composite applications in order to meet the demand of using environmentally friendly materials for composites. Fibre metal laminates (FMLs) are used in aerospace, automobile, marine and civil engineering applications, due to their excellent mechanical behaviors compared to traditional metals and their alloys. This study describes a novel fabrication of jute fibre reinforced aluminum metal laminates, using different jute fibre architectures (plain and twill fabric structures), wherein jute fibres were used in the skins and aluminum in the core layers. Jute fibres and aluminum sheets were chemically treated to enhance the compatibility and interfacial bonding at fibre-metals-matrix interfaces. FMLs were manufactured by hot pressing technique, after the application of wet lay-up process for the resin impregnation and they were further tested under tensile, flexural and impact loading conditions. While comparing results, the twill architecture showed improved tensile and flexural properties compared to plain fabric based FMLs. Chemical treatments on twill jute fibres and metal sheets further exceptionally enhanced the flexural properties (151 MPa flexural strength and 21.3 GPa modulus and they were increased by 186.5 % and 722.7 % respectively compared to the untreated jute fibre counterparts) of the laminates due to a significant improvement in the adhesion between the jute fibre and aluminum sheet after alkali treatment applied. Therefore, with these enhanced properties, jute based FML laminates can be used as sustainable composite materials in many structural applications.

7.
Zootaxa ; 5374(4): 594-600, 2023 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-38220839

RESUMEN

Two new species of Tumidiclava Girault (Hymenoptera: Trichogrammatidae), T. breviclavata Ikram & Yousuf sp. nov. and T. loharaensis is Ikram & Yousuf sp. nov. are described from India. A key to the Indian species of Tumidiclava Girault and redescription of Tumdiclava longiclavata Yousuf & Shafee are also provided.


Asunto(s)
Himenópteros , Animales
8.
Heliyon ; 9(11): e21520, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37942151

RESUMEN

The field of automated lung cancer diagnosis using Computed Tomography (CT) scans has been significantly advanced by the precise predictions offered by Convolutional Neural Network (CNN)-based classifiers. Critical areas of study include improving image quality, optimizing learning algorithms, and enhancing diagnostic accuracy. To facilitate a seamless transition from research laboratories to real-world applications, it is crucial to improve the technology's usability-a factor often neglected in current state-of-the-art research. Yet, current state-of-the-art research in this field frequently overlooks the need for expediting this process. This paper introduces Healthcare-As-A-Service (HAAS), an innovative concept inspired by Software-As-A-Service (SAAS) within the cloud computing paradigm. As a comprehensive lung cancer diagnosis service system, HAAS has the potential to reduce lung cancer mortality rates by providing early diagnosis opportunities to everyone. We present HAASNet, a cloud-compatible CNN that boasts an accuracy rate of 96.07%. By integrating HAASNet predictions with physio-symptomatic data from the Internet of Medical Things (IoMT), the proposed HAAS model generates accurate and reliable lung cancer diagnosis reports. Leveraging IoMT and cloud technology, the proposed service is globally accessible via the Internet, transcending geographic boundaries. This groundbreaking lung cancer diagnosis service achieves average precision, recall, and F1-scores of 96.47%, 95.39%, and 94.81%, respectively.

9.
Eur J Cardiothorac Surg ; 64(4)2023 10 04.
Artículo en Inglés | MEDLINE | ID: mdl-37522885

RESUMEN

OBJECTIVES: The aim of this study was to develop a method to quantify the peel force in an in vitro model simulating repair of ascending aortic dissections with tissue glue (Bioglue). METHODS: This study adapted an adhesive T-Peel test for the determination of the peel strength of adhesives by measuring the peeling force of a T-shaped bonded tissue. Measurements were performed on iatrogenic dissected ascending porcine aorta, which has been repaired with Bioglue using different pressure levels. Four conditions were tested: zero sample pressure according to the manufacturer's recommendation (n = 10), low (504 Pa; n = 11), moderate pressure (1711 Pa; n = 24) and pressure applied by a round shaped vascular 'Borst clamp' (1764 Pa; n = 23). Non-parametric one-way analysis of variance was applied for statistical significance. RESULTS: The median peel force (lower quartile, upper quartile) of aortic samples increased depending on the applied pressure: [no pressure 0.030 N/mm (0.016, 0.057), low pressure 0.040 N/mm (0.032, 0.070) and moderate pressure 0.214 N/mm (0.050, 0.304)]. Samples pressurized with the Borst clamp reached 0.078 N/mm (0.046, 0.152), which was comparable to the peel force of the unpeeled controls [0.107 N/mm (0.087, 0.124)]. Compared to samples without pressure, Bioglue with the application of the Borst clamp (P = 0.021) and with moderate pressure (P = 0.0007) performed significantly better. CONCLUSIONS: The novel T-Peel test offers an attractive method to test tissue glues in defined in vitro environments. Bioglue peel force increased with pressure on the aortic sample in contrast to low or no pressure as per the manufacturer's recommendation. Modifying current recommended use may aid in increasing effectiveness of this approach.


Asunto(s)
Disección de la Aorta Ascendente , Adhesivos Tisulares , Porcinos , Animales , Adhesivos , Adhesivos Tisulares/farmacología , Aorta/cirugía
10.
ACS Omega ; 8(50): 47856-47873, 2023 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-38144143

RESUMEN

In this work, microcrystalline cellulose (MCC) was isolated from jute sticks and sodium carboxymethyl cellulose (Na-CMC) was synthesized from the isolated MCC. Na-CMC is an anionic derivative of microcrystalline cellulose. The microcrystalline cellulose-based hydrogel (MCCH) and Na-CMC-based hydrogel (Na-CMCH) were prepared by using epichlorohydrin (ECH) as a crosslinker by a chemical crosslinking method. The isolated MCC, synthesized Na-CMC, and corresponding hydrogels were characterized by Fourier transform infrared (FTIR), X-ray diffraction (XRD), scanning electronic microscopy (SEM), and energy dispersive spectroscopy (EDS) for functional groups, crystallinity, surface morphology, and composite elemental composition, respectively. Pseudo-first-order, pseudo-second-order, and Elovich models were used to investigate the adsorption kinetics. The pseudo-second-order one is favorable for both hydrogels. Freundlich, Langmuir, and Temkin adsorption isotherm models were investigated. MCCH follows the Freundlich model (R2 = 0.9967), and Na-CMCH follows the Langmuir isotherm model (R2 = 0.9974). The methylene blue (MB) dye adsorption capacities of ionic (Na-CMCH) and nonionic (MCCH) hydrogels in different contact times (up to 600 min), initial concentrations (10-50 ppm), and temperatures (298-318 K) were investigated and compared. The maximum adsorption capacity of MCCH and Na-CMCH was 23.73 and 196.46 mg/g, respectively, and the removal efficiency of MB was determined to be 26.93% for MCCH and 58.73% for Na-CMCH. The Na-CMCH efficiently removed the MB from aqueous solutions as well as spiked industrial wastewater. The Na-CMCH also remarkably efficiently reduced priority metal ions from an industrial effluent. An effort has been made to utilize inexpensive, readily available, and environmentally friendly waste materials (jute sticks) to synthesize valuable adsorbent materials.

11.
ACS Omega ; 8(27): 24311-24322, 2023 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-37457457

RESUMEN

Natural-based lignocellulose fibrous materials can be used as a sustainable alternative to conventional fossil-based fibers such as glass fibers, in lightweight fiber-reinforced thermoplastic composites for marine, automotive, aerospace, or other advanced applications. However, one of the main challenges in using natural fiber-based thermoplastic composites is the low mechanical performance of composite structures. This can be improved significantly through the development of an optimized novel fiber architecture with enhanced fiber packing properties, following a low-cost production process. In this context, this study demonstrates a less energy-consuming and cheaper manufacturing process, for developing highly individualized short jute fiber-based dry fiber preform architecture, with an improved fiber packing property. Short jute fibers were chemically treated with alkali and PVA sizing treatments in the processing of new fiber preform architectures, and they were used in manufacturing of ultimate short jute fiber/polypropylene (PP) thermoplastic composites. The newly developed short fiber thermoplastic composites showed a significant improvement in mechanical properties (tensile, flexural, and impact) compared to any other natural fiber architecture-based (woven, knitted, nonwoven, unidirectional, etc.) composites found in the literature. Due to the use of new fiber architecture, the developed composites' fiber content was observed to increase. In addition, the compatibility of jute fibers with the polypropylene matrix was strengthened with the application of chemical treatments on highly individualized jute fibers. These reasons were responsible for the enhancement of mechanical properties of developed composites. Micromechanics of the fibers in composites were evaluated using the modified rule of the mixture and Halpin-Tsai equations for stiffness prediction of the composites in order to develop a theoretical understanding of newly developed composites' mechanics. It is thought that the improved mechanical performance of short jute fiber/PP thermoplastic composites can extend the use of these composites in many load-demanding applications, wherein normally synthetic fiber composites are used.

12.
Biochemistry ; 51(28): 5695-702, 2012 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-22734719

RESUMEN

Heat shock proteins (HSPs) play a critical role in many intracellular processes, including apoptosis and delivery of other proteins to intracellular compartments. Small HSPs have been shown previously to participate in many cellular functions, including IL-8 induction. Human adenovirus infection activates intracellular signaling, involving particularly the c-Src and mitogen-activated protein kinases [Natarajan, K., et al. (2003) J. Immunol. 170, 6234-6243]. HSP27 and MK2 are also phosphorylated, and c-Src, and its downstream targets, p38, ERK1/2, and c-Jun-terminal kinase (JNK), differentially mediate IL-8 and MCP-1 expression. Specifically, activation and translocation of transcription factor NFκB-p65 occurs in a p38-dependent fashion [Rajaiya, J., et al. (2009) Mol. Vision 15, 2879-2889]. Herein, we report a novel role for HSP27 in an association of p38 with NFκB-p65. Immunoprecipitation assays of virus-infected but not mock-infected cells revealed a signaling complex including p38 and NFκB-p65. Transfection with HSP27 short interfering RNA (siRNA) but not scrambled RNA disrupted this association and reduced the level of IL-8 expression. Transfection with HSP27 siRNA also reduced the level of nuclear localization of NFκB-p65 and p38. By use of tagged p38 mutants, we found that amino acids 279-347 of p38 are necessary for the association of p38 with NFκB-p65. These studies strongly suggest that HSP27, p38, and NFκB-p65 form a signalosome in virus-infected cells and influence downstream expression of pro-inflammatory mediators.


Asunto(s)
Infecciones por Adenovirus Humanos/metabolismo , Adenovirus Humanos/fisiología , Proteínas de Choque Térmico HSP27/fisiología , Infecciones por Adenovirus Humanos/virología , Células Cultivadas , Quimiocinas/biosíntesis , Humanos , Queratinocitos/virología , Subunidad p50 de NF-kappa B/metabolismo , Transporte de Proteínas , Transducción de Señal , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
13.
Proc Natl Acad Sci U S A ; 106(51): 21731-6, 2009 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-19995967

RESUMEN

Hydrogenosomes and mitosomes are mitochondrion-related organelles in anaerobic/microaerophilic eukaryotes with highly reduced and divergent functions. The full diversity of their content and function, however, has not been fully determined. To understand the central role of mitosomes in Entamoeba histolytica, a parasitic protozoon that causes amoebic dysentery and liver abscesses, we examined the proteomic profile of purified mitosomes. Using 2 discontinuous Percoll gradient centrifugation and MS analysis, we identified 95 putative mitosomal proteins. Immunofluorescence assay showed that 3 proteins involved in sulfate activation, ATP sulfurylase, APS kinase, and inorganic pyrophosphatase, as well as sodium/sulfate symporter, involved in sulfate uptake, were compartmentalized to mitosomes. We have also provided biochemical evidence that activated sulfate derivatives, adenosine-5'-phosphosulfate and 3'-phosphoadenosine-5'-phosphosulfate, were produced in mitosomes. Phylogenetic analysis showed that the aforementioned proteins and chaperones have distinct origins, suggesting the mosaic character of mitosomes in E. histolytica consisting of proteins derived from alpha-proteobacterial, delta-proteobacterial, and ancestral eukaryotic origins. These results suggest that sulfate activation is the major function of mitosomes in E. histolytica and that E. histolytica mitosomes represent a unique mitochondrion-related organelle with remarkable diversity.


Asunto(s)
Entamoeba histolytica/metabolismo , Orgánulos/metabolismo , Sulfatos/metabolismo , Centrifugación , Electroforesis en Gel de Poliacrilamida , Entamoeba histolytica/ultraestructura , Técnica del Anticuerpo Fluorescente , Filogenia
14.
Indian J Tuberc ; 69(4): 552-557, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36460388

RESUMEN

BACKGROUND: Tuberculosis is a major health problem contributing to significant morbidity and mortality. Early diagnosis and treatment is the key for TB control. Sputum microscopy is a rapid and inexpensive test but due to low and variable sensitivity, many cases can be missed. Culture is considered to be the gold standard but is time consuming. Gene Xpert is a novel and rapid cartridge based nucleic acid amplification test (CBNAAT) that can be used for prompt diagnosis. AIM: To compare the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of Gene Xpert with culture in diagnosing tuberculosis in sputum smear negative patients. METHODS: The study is a prospective observational study conducted from December 2017 to January 2019 on 189 patients, who were sputum smear negative but had signs and symptoms suggestive of tuberculosis. Their respiratory samples were taken (either sputum or bronchoalveolar lavage) and sent for Gene Xpert. The results were compared with culture, which was taken as the gold standard, and diagnostic accuracy was assessed. RESULT: A total of 189 patients were included in the study. In 25 patients sputum was taken and in 164 patients BAL was taken (which included 22 patients in whom sputum Gene Xpert was negative but there was high clinical suspicion of tuberculosis). The sensitivity, specificity, PPV and NPV of Gene Xpert in diagnosing smear negative pulmonary tuberculosis was found to be 96.3%, 81.3%, 87.5% and 94.2% respectively. CONCLUSION: Gene Xpert can be used as a rapid diagnostic tool in patients who are sputum smear negative but have clinical features highly suggestive of tuberculosis. It additionally helps in detecting rifampicin resistance. But every Gene Xpert positive case does not necessarily mean an active disease, therefore, past history of tuberculosis along with radiological signs of disease activity are to be considered. In case of negative Gene Xpert but high clinico-radiological suspicion of TB, patients should be followed up on regular intervals, while awaiting their culture.


Asunto(s)
Radiología , Tuberculosis Pulmonar , Humanos , Tuberculosis Pulmonar/diagnóstico , Esputo , Rifampin , Microscopía
15.
Comput Biol Med ; 146: 105539, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35483227

RESUMEN

The brain tumor is one of the deadliest cancerous diseases and its severity has turned it to the leading cause of cancer related mortality. The treatment procedure of the brain tumor depends on the type, location and size of the tumor. Relying solely on human inspection for precise categorization can lead to inevitably dangerous situation. This manual diagnosis process can be improved and accelerated through an automated Computer Aided Diagnosis (CADx) system. In this article, a novel approach using two-stage feature ensemble of deep Convolutional Neural Networks (CNN) is proposed for precise and automatic classification of brain tumors. Three unique Magnetic Resonance Imaging (MRI) datasets and a dataset merging all the unique datasets are considered. The datasets contain three types of brain tumor (meningioma, glioma, pituitary) and normal brain images. From five pre-trained models and a proposed CNN model, the best models are chosen and concatenated in two stages for feature extraction. The best classifier is also chosen among five different classifiers based on accuracy. From the extracted features, most substantial features are selected using Principal Component Analysis (PCA) and fed into the classifier. The robustness of the proposed two stage ensemble model is analyzed using several performance metrics and three different experiments. Through the prominent performance, the proposed model is able to outperform other existing models attaining an average accuracy of 99.13% by optimization of the developed algorithms. Here, the individual accuracy for Dataset 1, Dataset 2, Dataset 3, and Merged Dataset is 99.67%, 98.16%, 99.76%, and 98.96% respectively. Finally a User Interface (UI) is created using the proposed model for real time validation.


Asunto(s)
Neoplasias Encefálicas , Glioma , Algoritmos , Neoplasias Encefálicas/diagnóstico por imagen , Glioma/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética/métodos , Redes Neurales de la Computación
16.
ACS Omega ; 7(33): 29391-29405, 2022 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-36033678

RESUMEN

In this work, an HB pencil electrode (HBPE) was electrochemically modified by amino acids (AAs) glycine (GLY) and aspartic acid (ASA) and designated as GLY-HB and ASA-HB electrodes. They were used in the detection of dihydroxybenzene isomers (DHBIs) such as hydroquinone (HQ), catechol (CC), and resorcinol (RS), by cyclic voltammetry (CV), and by differential pulse voltammetry. HBPE was characterized by scanning electron microscopy and energy-dispersive X-ray spectroscopy. These three electrodes showed a linear relationship of current with concentration of DHBIs, and the electrochemical processes were diffusion controlled in all cases. In simultaneous detection, the limit of detection, based on signal-to-noise ratio (S/N = 3), for HQ, CC, and RS was 12.473, 16.132, and 25.25 µM, respectively, at bare HBPE; 5.498, 7.119, and 14.794 µM, respectively, at GLY-HB; and 22.459, 25.478, and 38.303 µM, respectively, at ASA-HB. The sensitivity for HQ, CC, and RS was 470.481, 363.781, and 232.416 µA/mM/cm2, respectively, at bare HBPE; 364.785, 282.712, and 135.560 µA/mM/cm2, respectively, at GLY-HB; and 374.483, 330.108, and 219.574, respectively, at ASA-HB. The interference studies clarified the suitability and reliability of the electrodes for the detection of HQ, CC, and RS in an environmental system. Real sample analysis was done using tap water, and the proposed electrodes expressed recovery with high reproducibility. Meanwhile, these three electrodes have excellent sensitivity and selectivity, which can be used as a promising technique for the detection of DHBIs simultaneously.

17.
ACS Omega ; 7(12): 10127-10136, 2022 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-35382272

RESUMEN

The fiber architecture can significantly influence the rate of impregnation of a resin in making composites and the load-bearing ability of individual fibers on testing of the loading directions. Moreover, achieving the maximum mechanical performance of a natural fiber composite selection of yarn liner density and optimization of fabric structure and further modification of the composites remains a great challenge for the composite research community. In this study, a number of jute-based woven derivatives (plain, 2/1 twill, 3/1 twill, zigzag based on a 2/2 twill, and diamond based on a 2/2 twill) have been constructed from similar linear densities of yarn. The effect of the fabric architecture and further modification of optimized composites by applying γ-radiation is also explained in this study. The experimental results show a 54% increase in tensile strength, a 75% increase in tensile modulus, a 69% increase in flexural strength, a 124% increase in flexural modulus, and 64% increase in impact strength of twill (3/1) structured jute fiber polyester composites in comparison to other plain and twill structured composites. A further mechanical improvement of around 20-30% is possible for the optimized twill structured composites by applying γ-radiation on the composites. An FTIR, TGA, and SEM study confirms the chemical, thermal, and fractographic changes after applying the modification of composites.

18.
IEEE J Transl Eng Health Med ; 10: 2700316, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35795873

RESUMEN

Human Activity Recognition (HAR) systems are devised for continuously observing human behavior - primarily in the fields of environmental compatibility, sports injury detection, senior care, rehabilitation, entertainment, and the surveillance in intelligent home settings. Inertial sensors, e.g., accelerometers, linear acceleration, and gyroscopes are frequently employed for this purpose, which are now compacted into smart devices, e.g., smartphones. Since the use of smartphones is so widespread now-a-days, activity data acquisition for the HAR systems is a pressing need. In this article, we have conducted the smartphone sensor-based raw data collection, namely H-Activity, using an Android-OS-based application for accelerometer, gyroscope, and linear acceleration. Furthermore, a hybrid deep learning model is proposed, coupling convolutional neural network and long-short term memory network (CNN-LSTM), empowered by the self-attention algorithm to enhance the predictive capabilities of the system. In addition to our collected dataset (H-Activity), the model has been evaluated with some benchmark datasets, e.g., MHEALTH, and UCI-HAR to demonstrate the comparative performance of our model. When compared to other models, the proposed model has an accuracy of 99.93% using our collected H-Activity data, and 98.76% and 93.11% using data from MHEALTH and UCI-HAR databases respectively, indicating its efficacy in recognizing human activity recognition. We hope that our developed model could be applicable in the clinical settings and collected data could be useful for further research.


Asunto(s)
Redes Neurales de la Computación , Dispositivos Electrónicos Vestibles , Algoritmos , Atención , Actividades Humanas , Humanos
19.
IEEE J Transl Eng Health Med ; 10: 1800712, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36226132

RESUMEN

Inherently ultrasound images are susceptible to noise which leads to several image quality issues. Hence, rating of an image's quality is crucial since diagnosing diseases requires accurate and high-quality ultrasound images. This research presents an intelligent architecture to rate the quality of ultrasound images. The formulated image quality recognition approach fuses feature from a Fuzzy convolutional neural network (fuzzy CNN) and a handcrafted feature extraction method. We implement the fuzzy layer in between the last max pooling and the fully connected layer of the multiple state-of-the-art CNN models to handle the uncertainty of information. Moreover, the fuzzy CNN uses Particle swarm optimization (PSO) as an optimizer. In addition, a novel Quantitative feature extraction machine (QFEM) extracts hand-crafted features from ultrasound images. Next, the proposed method uses different classifiers to predict the image quality. The classifiers categories ultrasound images into four types (normal, noisy, blurry, and distorted) instead of binary classification into good or poor-quality images. The results of the proposed method exhibit a significant performance in accuracy (99.62%), precision (99.62%), recall (99.61%), and f1-score (99.61%). This method will assist a physician in automatically rating informative ultrasound images with steadfast operation in real-time medical diagnosis.


Asunto(s)
Redes Neurales de la Computación , Aumento de la Imagen , Ultrasonografía
20.
Healthcare (Basel) ; 10(10)2022 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-36292417

RESUMEN

Computed tomography (CT) radiation dose management tools should be used whenever possible, particularly with the increasing demand for acquiring CT studies. Herein, we aim to assess the advantages and challenges faced with implementing two CT dose management tools. A second aim was to highlight CT examinations exceeding dose notification values (NVs) and define the common set of causes. A total of 13,037 CT examinations collected over a six-month period, were evaluated, using two independent CT dose management tools, a CT Dose Notification prospective-view tool (PVT) following CT Dose Check standards and a retrospective statistical-based view tool (RSVT). Dose NVs were set to twice the Local Diagnostic Reference Levels. There was a significant discrepancy between dose NV counts registered with prospective (4.15%) and retrospective (7.98%) tools using T-Test. A core difference is the dose configuration setup, with PVT and RSVT being dose per series and whole study, respectively. Both prospective and retrospective dose management tools were equally useful despite their technical difference. Configuring the CT prospective dose notification check tool using NVs that is based on DRLs has limitations, and one needs to establish dose NVs per series to overcome this technical hurdle. Technical challenges make the implementation of CT Dose Check standards puzzling.

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