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1.
Commun Biol ; 5(1): 666, 2022 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-35790808

RESUMEN

B.1.1.7 lineage SARS-CoV-2 is more transmissible, leads to greater clinical severity, and results in modest reductions in antibody neutralization. Subgenomic RNA (sgRNA) is produced by discontinuous transcription of the SARS-CoV-2 genome. Applying our tool (periscope) to ARTIC Network Oxford Nanopore Technologies genomic sequencing data from 4400 SARS-CoV-2 positive clinical samples, we show that normalised sgRNA is significantly increased in B.1.1.7 (alpha) infections (n = 879). This increase is seen over the previous dominant lineage in the UK, B.1.177 (n = 943), which is independent of genomic reads, E cycle threshold and days since symptom onset at sampling. A noncanonical sgRNA which could represent ORF9b is found in 98.4% of B.1.1.7 SARS-CoV-2 infections compared with only 13.8% of other lineages, with a 16-fold increase in median sgRNA abundance. We demonstrate that ORF9b protein levels are increased 6-fold in B.1.1.7 compared to a B lineage virus in vitro. We hypothesise that increased ORF9b in B.1.1.7 is a direct consequence of a triple nucleotide mutation in nucleocapsid (28280:GAT > CAT, D3L) creating a transcription regulatory-like sequence complementary to a region 3' of the genomic leader. These findings provide a unique insight into the biology of B.1.1.7 and support monitoring of sgRNA profiles to evaluate emerging potential variants of concern.


Asunto(s)
COVID-19 , ARN , COVID-19/diagnóstico , COVID-19/genética , Humanos , SARS-CoV-2/genética
2.
Neurologist ; 27(5): 263-265, 2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-34855661

RESUMEN

INTRODUCTION: Neurological manifestations of acute lymphoblastic leukemia (ALL) have been reported as cranial neuropathies or meningeal symptoms most common in children. However, ALL can rarely involve the nerve roots causing symmetrical polyradiculopathy which can present with rapid onset paralysis, mimicking Guillain-Barré Syndrome (GBS). The symmetrical polyradiculopathy can be the earliest manifestation of ALL occurring even before the hematological and systemic manifestations. CASE REPORT: We report a case of a healthy 29-year-old man who presented with subacute bilateral lower extremity weakness and numbness preceded by a respiratory infection. He was initially treated as a suspected (GBS) but cerebrospinal fluid (CSF) findings suggested an alternative diagnosis. His prior TB exposure created a diagnostic confusion. Lumbar spine magnetic resonance imaging revealed nerve root enhancements at L4-L5 and L5-S1 that are seen in GBS and TB arachnoidids. Brain magnetic resonance imaging demonstrated bilateral distention of the optic nerve sheath complexes with CSF suggestive of intracranial hypertension. CSF revealed elevated protein, nucleated cells 2145 leukocytes/mm 3 , numerous atypical lymphoid cells. He was later diagnosed with ALL associated symmetrical polyradiculopathy presenting with GBS-like symptoms. CONCLUSION: Symmetrical polyradiculopathy is a rare complication of ALL and can be confused with acute inflammatory demyelinating polyneuropathy. ALL associated polyradiculopathy in young individuals can be clinically indistinguishable from GBS. Our case highlights that when CSF findings are atypical for GBS, ALL should be considered on the differential diagnosis in patients presenting with GBS like symptoms.


Asunto(s)
Enfermedades de los Nervios Craneales , Síndrome de Guillain-Barré , Polirradiculopatía , Leucemia-Linfoma Linfoblástico de Células Precursoras , Adulto , Niño , Síndrome de Guillain-Barré/complicaciones , Humanos , Masculino , Debilidad Muscular , Polirradiculopatía/complicaciones , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicaciones , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico
3.
Cureus ; 13(3): e13950, 2021 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-33884225

RESUMEN

Acute arterial strokes in children are rare but can potentially cause lasting and often permanent neurological deficits. Mechanical thrombectomy has a well-established efficacy and safety profile in adult stroke management, but in the pediatric population, it is yet to be proven efficacious and safe. We present a case of a seven-year-old male who presented with multiple episodes of generalized tonic-clonic seizures after sustaining a neck injury by falling from a trampoline. National Institutes of Health (NIH) on presentation was 21. Neurological exam revealed dilated nonreactive pupils, dysconjugate gaze, severe dysarthria, bilateral ptosis, and movement of upper and lower extremities only to noxious stimuli. Magnetic resonance imaging (MRI) of brain without contrast revealed infarcted areas in the left pons, midbrain, and cerebellar regions. Computed tomographic angiogram (CTA) of head demonstrated left vertebral artery dissection with associated complete occlusion of the distal basilar artery. Successful recanalization was achieved with mechanical thrombectomy six hours after presentation. Mechanical thrombectomy treatment resulted in a significant neurological recovery with NIH of 1. This case supports the growing evidence of the efficacy and safety of mechanical thrombectomy in children.

4.
J Tradit Chin Med ; 32(4): 616-20, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23427398

RESUMEN

OBJECTIVE: Plants produce a variety of useful bioactive materials that have been used to cure different ailments of human beings. With the same idea in mind, the crude methanolic extract and various fractions of Solanum surrattense were screened for antibacterial, antifungal, phytotoxic and heamagglutination activities. METHODS: Standardized assays were followed for the determination of antibacterial, antifungal phytotoxic and heamagglutination activity. RESULTS: The results of the antibacterial showed that crude methanolic extract was significantly active against Staphylococcus aureus (86%) The n-hexane fraction showed good activity against Pseudomonas aerogenosa (66.6%) and Bacillus subtilus (66.6%). The crude methanolic extract and various fractions were inactive against all test fungi. The crude methanolic extract, n-hexane, CHCl3 and aqueous fractions showed moderate phytotoxic activities of 46.67%, 40.00%, 33.34% and 33.34% respectively at 1000 microg/mL. The crude methanolic extract and various fractions S. surrattense were unable to agglutinate RBCs of the human blood indicating that this species lack phytolectins. CONCLUSION: The test sample showed significant antibacterial activity, no antifungal and heamagglutination activity while moderate phytotoxic was observed against Lemna minor L.


Asunto(s)
Antibacterianos/farmacología , Antifúngicos/farmacología , Extractos Vegetales/farmacología , Solanum/química , Antibacterianos/toxicidad , Antifúngicos/toxicidad , Bacterias/efectos de los fármacos , Eritrocitos/efectos de los fármacos , Eritrocitos/fisiología , Hongos/efectos de los fármacos , Hemaglutinación/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/toxicidad
5.
J Nanosci Nanotechnol ; 11(10): 9050-6, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22400301

RESUMEN

Room temperature electron spin resonance spectra of epoxy resins loaded with various concentrations of multiwalled carbon nanotubes of various lengths are analyzed. The resonance spectrum near the free electron line position is dominated by a single almost symmetric line assigned to delocalized electrons residing on multiwalled carbon nanotubes. The experimental research shown that: (1) The dependence of the g-factor on nanotubes length is controlled by the distortions of multiwalled carbon nanotubes. (2) The dependence of the g-factor on the concentration of multi-walled nanotubes reflects the interactions between electrons localized on different nanotubes. In insulating composites, the resonance line width broadens as the length and the concentration of multiwalled carbon nanotubes is increased. (3) For conducting composites, the dependence of the electron spin resonance line width on the length and concentration of multiwalled carbon nanotubes is controlled by Elliott contribution and exchange interactions, respectively. (4) The concentration of conduction electrons increases as the length and the concentration of multiwalled carbon nanotubes are increased.

6.
J Nanosci Nanotechnol ; 9(6): 3555-61, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19504881

RESUMEN

This paper reports on the systematic optical characterization of Er3+ (1.0%) doped lead-zinc-borate glass from the measured absorption, luminescence and fluorescence lifetime decay curve profiles. By the application of the Judd-Ofelt theory, spectral intensities of the absorption bands have been analysed and these absorption results have been used in evaluating the luminescence properties of the Er3+ doped lead-zinc-borate glass. Stimulated emission cross-sections (sigmapE) of the measured emission transitions have been computed. Based on the measured glass density, and refractive indices, other related physical parameters have also been evaluated. Further, the structural and morphology of the glass material have also been investigated from X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy analysis.

7.
J Nanosci Nanotechnol ; 9(6): 3672-7, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19504901

RESUMEN

This paper reports on the development and spectral analysis of Sm3+ (1.0%) and Dy3+ (1.0%) doped lithium-boro-tellurite glasses. A bright orange (4G5/2-->6H7/2) along with a red (4G5/2-->6H9/2) and a yellow (4G5/2-->6H5/2) emission transition have been measured from Sm3+ doped lithium-boro-tellurite glass. Both blue (4F9/2-->6H15/2) and yellow (4F9/2-->6H13/2) emission bands have been obtained from Dy3+ glass. From the measured decay profiles, the lifetimes of the emissions of the Sm3+ glass (4G5/2-->6H5/2, 7/2, 9/2 and 11/2) at an excitation of 401 nm have been found to be in the range 0.47-0.81 ms, and with respect to the Dy3+ emissions (4F9/2-->6H15/2 and 13/2), with excitation at 450 nm, are measured to be in the range of 0.302-0.307 ms. Stimulated emission cross-sections (sigmapE) of the measured emission transitions have also been computed and the values are in the range of (0.38-1.20) x 10(-20) cm2 for Sm3+ and for Dy3+ doped lithium-boro-tellurite glass the values are (0.66-1.39) x 10(-20) cm2.

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