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1.
Heliyon ; 10(5): e27393, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38495203

RESUMEN

This paper introduces a compact Multiple Input Multiple Output (MIMO) Ultrawideband (UWB) antenna seamlessly integrated with the Ku band, tailored for wireless communication applications. The MIMO antenna employs octagonal radiators, crafted from a tapered microstrip line-fed rectangular patch, etched on an economically efficient FR4 substrate measuring 40 × 23 mm2. The octagonal configuration is achieved by introducing a rectangular patch to the central radiator, while parasitic stubs are strategically employed to mitigate coupling among MIMO elements. The antenna demonstrates an extensive operational bandwidth spanning 3.28-17.8 GHz, covering UWB, extended UWB, and Ku-band spectrums globally allocated for heterogeneous applications. With a peak gain of 4.93 dBi and an efficiency of 95.34%, the proposed MIMO antenna showcases superior performance. Key performance parameters, including a low envelope correlation coefficient (ECC) of 0.003 and a substantial diversity gain (DG) of 9.997 dB, are thoroughly analyzed. Comparative assessments against recent works validate the novelty and potential of the proposed antenna for integration into compact wireless systems. This study underscores the success of the antenna design in achieving a harmonious balance of compactness, wide operational bandwidth, and high performance, positioning it as a promising candidate for diverse wireless communication applications.

2.
Mult Scler ; 30(4-5): 505-515, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38419027

RESUMEN

BACKGROUND: Performing routine brain magnetic resonance imaging (MRI) is widely accepted as the standard of care for disease monitoring in multiple sclerosis (MS), but the utility of performing routine spinal cord (SC) MRI for this purpose is still debatable. OBJECTIVE: This study aimed to measure the frequency of new isolated cervical spinal cord lesions (CSLs) in people with MS (pwMS) undergoing routine brain and cervical SC-MRI for disease monitoring and determine the factors associated with the development of new CSLs and their prognostic value. METHODS: We retrospectively identified 1576 pwMS who underwent follow-up 3T brain and cervical SC-MRI over a 9-month period. MRI was reviewed for the presence of new brain lesions (BLs) and CSLs. Clinical records were reviewed for interval relapses between sequential scans and subsequent clinical relapse and disability worsening after the follow-up MRI. RESULTS: In 1285 pwMS (median interval: 13-14 months) who were clinically stable with respect to relapses, 73 (5.7%) had new CSLs, of which 49 (3.8%) had concomitant new BLs and 24 (1.9%) had new isolated CSLs only. New asymptomatic CSLs were associated with ⩾ 3 prior relapses (p = 0.04), no disease-modifying therapy (DMT) use (p = 0.048), and ⩾ 3 new BLs (p < 0.001); ⩾ 3 new BLs (OR: 7.11, 95% CI: 4.3-11.7, p < 0.001) remained independently associated with new CSLs on multivariable analysis. Having new asymptomatic CSLs was not independently associated with subsequent relapse or disability worsening after the follow-up MRI (median follow-up time of 26 months). CONCLUSION: Routine brain and cervical SC-MRI detected new isolated CSLs in only < 2% of clinically stable pwMS. Developing new asymptomatic CSLs was associated with concomitant new BLs and did not confer an independent increased risk of relapse or disability worsening. Performing SC-MRI may not be warranted for routine monitoring in most pwMS, and performing only brain MRI may be sufficient to capture the vast majority of clinically silent disease activity.


Asunto(s)
Médula Cervical , Esclerosis Múltiple , Enfermedades de la Médula Espinal , Humanos , Esclerosis Múltiple/diagnóstico por imagen , Esclerosis Múltiple/patología , Médula Cervical/diagnóstico por imagen , Médula Cervical/patología , Estudios Retrospectivos , Progresión de la Enfermedad , Médula Espinal/diagnóstico por imagen , Médula Espinal/patología , Imagen por Resonancia Magnética/métodos , Enfermedades de la Médula Espinal/patología , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Recurrencia
3.
J Mol Graph Model ; 128: 108719, 2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-38324968

RESUMEN

This report provides detailed insights into the interaction of fifty monoclonal antibodies with two recent Omicron variants, BA1 and BA2. It has been observed that numerous mutations in the receptor binding domain (RBD) result in significant structural changes in Omicron, enhancing its ability to mediate viral infections compared to other variants of concern. The following antibodies, namely JX3S304, 7KMG, 7CH4, 7BELCOVOX45, 7CDJ, 7C01, 7JX3S2H14, 6XCA, 7CDI, 7JMO, 7B3O, 6ZER, 6XC7CR3022, JX3S309, 6XC7CC123, 7CM4, 7KMI, 7L7EAZD8895, exhibit a superior binding affinity towards the Spike when compared to the reference CR3022. Four best-docked systems were subjected to further testing through molecular dynamics (MD) simulations. The MM/GBSA free energy for the top-scored complexes of BA1 variant are BA1_JX3S3O4, BA1_7KMI, BA1_7CH4, and BA1_7KMG, with respective values of -56.120 kcal/mol, -41.30 kcal/mol, -17.546 kcal/mol, and -8.527 kcal/mol; and of BA2 variant are BA2_JX3S3O4, BA2_7CM4, BA2_KMG, and BA2_7CH4, with respective values of -40.903 kcal/mol, -23.416 kcal/mol, -17.350 kcal/mol, and -5.460 kcal/mol. Detailed structural/energetic parameters, principal component analysis, and free energy landscape (FEL) studies reveal a significant decrease in antibody resistance due to the disappearance of numerous hydrogen bond interactions and various metastable states. We believe that these crucial mechanistic insights will contribute to breakthroughs in SARS-CoV-2 research.


Asunto(s)
COVID-19 , Simulación de Dinámica Molecular , Humanos , SARS-CoV-2 , Anticuerpos Monoclonales
4.
Cell Biochem Biophys ; 80(3): 519-536, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35701692

RESUMEN

Metabolic status of the cells is important in the expression of the angiogenic phenotype in endothelial cells. Our earlier studies demonstrated the effects of metabolites such as lactate, citrate and lipoxygenase products, on VEGFA-VEGFR2 signaling pathway. Though this link between metabolite status and molecular mechanisms of angiogenesis is becoming evident, it is not clear how it affects genome-level expression in endothelial cells, critical to angiogenesis. In the present study, computational analysis was carried out on the transcriptome data of 4 different datasets where HUVECs were exposed to low and high glucose, both in vitro and in vivo, and the expression of a key enzyme involved in glucose metabolism is altered. The differentially expressed genes belonging to both VEGFA-VEGFR2 signaling pathway, as well as several VEGF signature genes as hub genes were also identified. These findings suggest the metabolite dependence, particularly glucose dependence, of angiogenesis, involving modulation of genome-level expression of angiogenesis- functional genome. This is important in tumor angiogenesis where reprogramming of metabolism is critical.


Asunto(s)
Factor A de Crecimiento Endotelial Vascular , Receptor 2 de Factores de Crecimiento Endotelial Vascular , Inhibidores de la Angiogénesis/uso terapéutico , Perfilación de la Expresión Génica , Glucosa/metabolismo , Células Endoteliales de la Vena Umbilical Humana , Humanos , Neovascularización Patológica/genética , Factor A de Crecimiento Endotelial Vascular/metabolismo , Receptor 2 de Factores de Crecimiento Endotelial Vascular/genética , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismo , Receptor 2 de Factores de Crecimiento Endotelial Vascular/uso terapéutico
5.
J Cell Commun Signal ; 13(4): 561-571, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31840205

RESUMEN

Vascular Endothelial Growth Factor-A (VEGFA) signaling is crucial to the cellular processes involved in angiogenesis. Previously, we assembled a network of molecular reactions induced by VEGFA in human umbilical vein endothelial cell populations. Considering transcriptome as a read-out of the transcriptional and epigenomic regulatory network, we now present an analysis of VEGFA-induced temporal transcriptome datasets from 6 non-synchronized studies. From these datasets, applying a confidence criterion, a set of early VEGFA-responsive signature genes were derived and evaluated for their co-expression potential with respect to multiple cancer gene expression datasets. Further, inclusive of a set of ligand-receptor pairs, a list of ligand and receptor signaling systems that potentially fine-tune the endothelial cell functions subsequent to VEGFA signaling were also derived. We believe that a number of these signaling systems would concurrently and/or hierarchically fine-tune the signaling network of endothelial cell populations towards the processes associated with angiogenesis through autocrine, paracrine, juxtacrine, and matricrine modes. By further analysis of published literature on VEGFA signaling, we also present an improved update-version of our previous VEGFA signaling network model in endothelial cells as a platform for analysis of cross-talk with these signaling systems.

6.
Indian J Radiol Imaging ; 28(3): 296-304, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30319205

RESUMEN

PCNSL (primary central nervous system lymphoma) is a chemosensitive and radiosensitive tumor, and early diagnosis has a significant impact on management. Unlike many other brain tumors, radical surgical excision of PCNSLs is not indicated because these lesions are highly infiltrative and even partial resection leads to a bad prognosis. The goal of this study is to highlight the unusual radiological presentation of PCNSLs and increase the awareness, familiarity, and global database of our observations that pose a challenge on management.

7.
Indian J Radiol Imaging ; 27(3): 263-267, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29089670

RESUMEN

When surgical decompression of cervical spine is considered, multilevel cervical corpectomy with long strut grafts is the preferred treatment. This procedure is used in a variety of pathologies including degenerative disease, tumors, trauma and infection. Corpectomy with interbody grafting helps in adequate spinal canal and neural decompression compared to multilevel discectomy, which could be difficult as well as inadequate. Fibular/iliac strut grafts are used for reconstruction along with a stabilizing hardware in this procedure. So far, complete imaging spectrum of complications exclusive to strut graft has not been reported in the literature. This pictorial essay presents complications exclusive to the strut graft, utility of advanced imaging in diagnosis and a brief note on the clinical management of complications.

8.
Asian J Neurosurg ; 12(4): 741-742, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29114299

RESUMEN

We describe a case of dural-based homogenously enhancing fungal granuloma in a 29-year-old male who presented with 3 months history of headache. The peculiarity of the case was that there were streaky areas of enhancement around the lesion in the brain parenchyma which resembled tree-in-bud like appearance. The patient underwent surgery and histopathological analysis revealed numerous Aspergillus hyphae. To the best of our knowledge, this is the first case report of a fungal granuloma with atypical parenchymal enhancement pattern.

12.
J Neurosci Rural Pract ; 3(3): 408-10, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23189017

RESUMEN

We describe a case report where the diagnosis of sporadic Creutzfeldt-Jakob disease(CJD) was suspected by the magnetic resonance imaging (MRI) radiologist in a 75-year-old lady who presented with rapid cognitive decline. MRI revealed cortical T2 and FLAIR(fluid attenuation and inversion recovery) hyperintensities in bilateral fronto-parietal and temporo-occipital locations and showed significant restriction on diffusion-weighted images(DWI). In this case report, we discuss the role of MRI to suspect the diagnosis of CJD in appropriate clinical settings.

13.
Singapore Med J ; 53(8): e179-81, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22941149

RESUMEN

Intracranial epidermoid cysts are relatively rare congenital inclusion cysts. They are the third most common cerebellopontine angle cistern mass after vestibular schwannoma and meningioma. White epidermoid is a rare variant. We present the first case, to our knowledge, of a white epidermoid cyst anterior to the pontomedullary junction, emphasising its imaging appearance, location and the importance of pre-operative diagnosis, which may reduce operative complications.


Asunto(s)
Enfermedades Cerebelosas/diagnóstico , Ángulo Pontocerebeloso/diagnóstico por imagen , Quiste Epidérmico/diagnóstico , Acúfeno/etiología , Adolescente , Enfermedades Cerebelosas/complicaciones , Quiste Epidérmico/complicaciones , Humanos , Masculino , Tomografía Computarizada por Rayos X
14.
J Emerg Trauma Shock ; 5(3): 250-2, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22988405

RESUMEN

Arachnoiditis ossificans is a rare chronic disorder characterized by the presence of calcification/ ossification of the spinal arachnoid. We describe the computed tomography (CT) and magnetic resonance imaging (MRI) findings of arachnoiditis ossificans as sequelae to trauma in a 30-year-old patient. This imaging diagnosis becomes important to alert the clinician as most of them can be treated by conservative management.

15.
Clin Neuropathol ; 31(5): 374-8, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22541779

RESUMEN

We present 2 rare cases of mixed schwannoma with meningioma. The first case was sporadic, in a 38-year-old female in cervical spine (C2). The second case was a 24-year-old female, associated with NF-2, involving bilateral cerebellopontine angle with extension into the left cavernous sinus, sellar region with erosion of the petrous ridge and multiple intradural extramedullary lesions in the spinal cord suggestive of neurofibromas. To date only 12 cases of such tumors are documented in the literature. To the best of our knowledge this is the first case of sporadic mixed schwannoma with meningioma in cervical spine (C2).


Asunto(s)
Neoplasias Meníngeas/patología , Meningioma/patología , Neoplasias Complejas y Mixtas/patología , Neurilemoma/patología , Adulto , Biomarcadores de Tumor/análisis , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Femenino , Humanos , Inmunohistoquímica , Neoplasias Meníngeas/metabolismo , Meningioma/metabolismo , Neoplasias Complejas y Mixtas/metabolismo , Neurilemoma/metabolismo , Neoplasias de la Médula Espinal/metabolismo , Neoplasias de la Médula Espinal/patología , Adulto Joven
16.
Diagn Cytopathol ; 40(2): 155-8, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22246933

RESUMEN

We report a rare case of recurrent chordoid glioma in suprasellar region with extension into the third ventricle diagnosed peroperatively. On MRI, a brilliantly contrast enhancing lesion in the suprasellar region extending superiorly into the third ventricle and measuring 2.5 × 3 × 3.5 cm was identified. Patient had a previous history of subtotal removal of the tumor 8 months back and had received 56 Gy of postoperative radiotherapy. On smear preparation the tumor was composed of cells arranged in chords and rows in a myxoid background with sprinkling of lymphocytes. The individual cells were polygonal with moderate amount of faintly eosinophilic cytoplasm with cytoplasmic vacoules in few cells. The nuclei showed fine chromatin with small prominent nucleoli. Paraffin sections confirmed the diagnosis and on immunohistochemistry the tumor cells showed strong positivity for GFAP and focal weak positivity for EMA with low MIB-1 labeling index (<1%). To the best of our knowledge this is the first documented case of chordoid glioma described on crush cytology.


Asunto(s)
Neoplasias Encefálicas/patología , Glioma/patología , Recurrencia Local de Neoplasia , Biomarcadores de Tumor/análisis , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/cirugía , Citodiagnóstico , Glioma/diagnóstico , Glioma/radioterapia , Glioma/cirugía , Humanos , Inmunohistoquímica , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Proteínas del Tejido Nervioso/análisis , Ubiquitina-Proteína Ligasas/análisis
17.
Singapore medical journal ; : e179-81, 2012.
Artículo en Inglés | WPRIM (Pacífico Occidental) | ID: wpr-249671

RESUMEN

Intracranial epidermoid cysts are relatively rare congenital inclusion cysts. They are the third most common cerebellopontine angle cistern mass after vestibular schwannoma and meningioma. White epidermoid is a rare variant. We present the first case, to our knowledge, of a white epidermoid cyst anterior to the pontomedullary junction, emphasising its imaging appearance, location and the importance of pre-operative diagnosis, which may reduce operative complications.


Asunto(s)
Adolescente , Humanos , Masculino , Enfermedades Cerebelosas , Diagnóstico , Ángulo Pontocerebeloso , Diagnóstico por Imagen , Quiste Epidérmico , Diagnóstico , Acúfeno , Tomografía Computarizada por Rayos X
18.
Br J Radiol ; 84(1003): e138-41, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21697409

RESUMEN

We report the first case of extensive involvement of isolated intracranial Rosai-Dorfman's disease (RDD) in a child. Our case is unique because it presents with involvement of the middle cranial fossa, cavernous sinus, pituitary gland, orbit, ethmoid and sphenoid sinuses. Previous cases of intracranial RDD in children have reported separate involvement of cavernous sinus, suprasellar region, and frontal and petroclival regions. Involvement of the pituitary gland has so far not been reported. A 14-year-old male presented with a medical history of loss of vision, raised erythrocyte sedimentation rate (ESR), and abnormal prolactin and cortisol levels. Radiologically the diagnosis was meningioma. The histopathological diagnosis was RDD with emperipolesis and S-100 positivity. RDD is a histiocytic proliferation of unknown aetiology, which commonly affects lymph nodes. Uncommonly it involves the extranodal sites and rarely the central nervous system (CNS). 80 cases of RDD involving CNS have been reported in the literature, and only 5 were in children. Although the definitive diagnosis of RDD disease is based on the histopathology report, it should be included in the differentials of a lesion mimicking meningioma especially in children.


Asunto(s)
Histiocitosis Sinusal/diagnóstico , Neoplasias Meníngeas/diagnóstico , Meningioma/diagnóstico , Adolescente , Fosa Craneal Media/diagnóstico por imagen , Fosa Craneal Media/patología , Histiocitos/patología , Humanos , Inmunohistoquímica , Masculino , Tomografía Computarizada por Rayos X
19.
Neurol India ; 59(1): 120-1, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21339679

RESUMEN

Spontaneous pneumorrhachis, non-traumatic, non-iatrogenic air within the spinal canal, is a very rare occurrence. We report a case of spontaneous pneumorrhachis, multiple air pockets in the epidural space, with vacuum discs and spndylolisthesis. Probably this is the first report of such case.


Asunto(s)
Vértebras Lumbares/patología , Neumocéfalo/complicaciones , Sacro/patología , Espondilolistesis/complicaciones , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad
20.
Nepal Med Coll J ; 12(2): 123-4, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21222412

RESUMEN

Congenital anomalies of the urinary tract system are common. The ectopic pelvic kidney is a rare anomaly about 1:2500 live births, left side being more common. Here we are reporting a case of left ectopic kidney with non rotation and morphologically normal right kidney. The case was found during routine dissection in the department of anatomy in an adult male cadaver. There were no other anomalies observed.


Asunto(s)
Riñón/anomalías , Adulto , Humanos , Masculino , Arteria Renal/anomalías
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