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1.
Sci Rep ; 13(1): 12468, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37528131

RESUMEN

Ferromagnetic films with perpendicular magnetic anisotropy are of interest in spintronics and superconducting spintronics. Perpendicular magnetic anisotropy can be achieved in thin ferromagnetic multilayer structures, when the anisotropy is driven by carefully engineered interfaces. Devices with multiple interfaces are disadvantageous for our application in superconducting spintronics, where the current perpendicular to plane is affected by the interfaces. Robust intrinsic PMA can be achieved in certain Co[Formula: see text]Pt[Formula: see text] alloys and compounds at any thickness, without increasing the number of interfaces. Here, we grow equiatomic Co[Formula: see text]Pt[Formula: see text] and report a comprehensive study on the structural, magnetic, and spin-polarisation properties in the [Formula: see text] and [Formula: see text] ordered compounds. Primarily, interest in Co[Formula: see text]Pt[Formula: see text] has been in the [Formula: see text] crystal structure, where layers of Pt and Co are stacked alternately in the [100] direction. There has been less work on [Formula: see text] crystal structure, where the stacking is in the [111] direction. For the latter [Formula: see text] crystal structure, we find magnetic anisotropy perpendicular to the film plane. For the former [Formula: see text] crystal structure, the magnetic anisotropy is perpendicular to the [100] plane, which is neither in-plane or out-of-plane in our samples. We obtain a value for the ballistic spin polarisation of the [Formula: see text] and [Formula: see text] Co[Formula: see text]Pt[Formula: see text] to be [Formula: see text].

2.
J Postgrad Med ; 67(3): 146-153, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34380801

RESUMEN

Context: Emphysematous pyelonephritis (EPN) is a dangerous necrotizing infection of the kidney involving the diabetics with a high case fatality rate. Recent medical literature has shown shifting of treatment strategy from conventional radical approach to minimally invasive approach. Aims: The aim of our study was to assess the role of minimally invasive stepwise decompression techniques in the management of EPN and preservation of the renal unit. Settings and Design: : This was a retrospective observational study conducted from June 2017 to April 2020 at a tertiary care centre. Material and Methods: We reviewed the hospital online records of 18 patients diagnosed with EPN for patient demographics, clinical profiles, co-morbidities, laboratory and, radiological investigations, surgical interventions performed and the outcomes. The severity of EPN was graded as per the Huang classification. Patients underwent surgical interventions as per the treatment protocol and response was assessed. Statistical Analysis Used: Descriptive statistics was applied. Results: Diabetes mellitus was present in 15 (83.3%) patients along with urinary tract obstruction in 8 (44.4%) patients. Flank pain (77.7%) was the most common presenting clinical feature while Escherichia coli (55.5%) were the most common causative organism. Most patients (50%) had Type- II EPN, all of which were managed successfully by minimally invasive procedures. In total seventeen patients (94.4%) responded well while one patient (5.5%) underwent nephrectomy with no mortality. Conclusions: Renal salvage in EPN requires multidisciplinary approach including the initial medical management followed by properly selected stepwise decompressive surgical techniques. Conservative management and decompression techniques have shown to improve patient's outcome, reducing the traditional morbidity associated with nephrectomy.


Asunto(s)
Descompresión Quirúrgica/métodos , Complicaciones de la Diabetes/diagnóstico , Enfisema/cirugía , Nefrectomía/métodos , Pielonefritis/cirugía , Infecciones Urinarias/microbiología , Dolor Abdominal/etiología , Complicaciones de la Diabetes/terapia , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/tratamiento farmacológico , Drenaje/métodos , Enfisema/etiología , Humanos , Riñón/diagnóstico por imagen , Procedimientos Quirúrgicos Mínimamente Invasivos , Pielonefritis/complicaciones , Estudios Retrospectivos , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Infecciones Urinarias/complicaciones
3.
AJNR Am J Neuroradiol ; 42(1): 173-177, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33214180

RESUMEN

BACKGROUND AND PURPOSE: Arterial stroke is a rare-but-reported complication in patients with posterior fossa brain malformations, hemangiomas, arterial anomalies, coarctation of the aorta and cardiac defects, and eye abnormalities (PHACE) syndrome. Currently, stroke risk is inferred by the severity of arterial anomalies identified on MRA, though no evidenced-based data exist. The purpose of our study was to determine whether arterial spin-labeling MR imaging perfusion can detect alterations in CBF in patients with PHACE syndrome. MATERIALS AND METHODS: Records were reviewed from 3 institutions for all patients with PHACE syndrome who underwent arterial spin-labeling from 2000 to 2019. CBF was qualitatively investigated with arterial spin-labeling to determine whether there was decreased or normal perfusion. Arterial anomalies were characterized on MRA imaging, and parenchymal brain findings were evaluated on conventional MR imaging sequences. RESULTS: Forty-one patients with PHACE syndrome had arterial spin-labeling imaging. There were 30 females and 11 males (age range, 7 days to 15 years). Of the 41 patients, 10 (24%) had decreased CBF signal corresponding to a major arterial territory. Ten of 10 patients had decreased CBF signal in the anterior circulation, 2/10 had decreased anterior and posterior circulation CBF signal, 2/10 had decreased bilateral anterior circulation CBF signal, and 1/10 had globally decreased CBF signal. Forty of 41 (97.5%) patients had at least 1 arteriopathy, and in those with decreased CBF signal, the arteriopathy corresponded to the CBF signal alteration in 10/10 patients. CONCLUSIONS: Arterial spin-labeling can potentially characterize hemodynamic changes in patients with PHACE syndrome.


Asunto(s)
Coartación Aórtica/diagnóstico por imagen , Coartación Aórtica/patología , Circulación Cerebrovascular , Espectroscopía de Resonancia por Spin del Electrón/métodos , Anomalías del Ojo/diagnóstico por imagen , Anomalías del Ojo/patología , Síndromes Neurocutáneos/diagnóstico por imagen , Síndromes Neurocutáneos/patología , Adolescente , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Imagen por Resonancia Magnética/métodos , Masculino , Imagen de Perfusión/métodos , Marcadores de Spin , Síndrome
4.
J Cutan Pathol ; 47(7): 628-632, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32020668

RESUMEN

We report a case of a 76-year-old man presenting with a 12-month history of a solitary lesion on his scalp. The histopathology was consistent with a grade 2/3 osteosarcoma extending to the subcutis. Full-body imaging excluded any involvement of the underlying bony tissue or solid organ malignancy, thus a diagnosis of primary cutaneous osteosarcoma (PCO) was made. Given the exceedingly rare nature of PCO, we discuss the clinico-pathological features of this case and those previously reported in the literature.


Asunto(s)
Neoplasias de Cabeza y Cuello/inmunología , Huésped Inmunocomprometido , Osteosarcoma/inmunología , Cuero Cabelludo/patología , Neoplasias Cutáneas/inmunología , Anciano , Neoplasias de Cabeza y Cuello/patología , Trasplante de Corazón , Humanos , Inmunosupresores/uso terapéutico , Masculino , Osteosarcoma/patología , Neoplasias Cutáneas/patología
5.
AJNR Am J Neuroradiol ; 38(10): E65-E73, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28860215

RESUMEN

INTRODUCTION: Functional MR imaging is increasingly being used for presurgical language assessment in the treatment of patients with brain tumors, epilepsy, vascular malformations, and other conditions. The inherent complexity of fMRI, which includes numerous processing steps and selective analyses, is compounded by institution-unique approaches to patient training, paradigm choice, and an eclectic array of postprocessing options from various vendors. Consequently, institutions perform fMRI in such markedly different manners that data sharing, comparison, and generalization of results are difficult. The American Society of Functional Neuroradiology proposes widespread adoption of common fMRI language paradigms as the first step in countering this lost opportunity to advance our knowledge and improve patient care. LANGUAGE PARADIGM REVIEW PROCESS: A taskforce of American Society of Functional Neuroradiology members from multiple institutions used a broad literature review, member polls, and expert opinion to converge on 2 sets of standard language paradigms that strike a balance between ease of application and clinical usefulness. ASFNR RECOMMENDATIONS: The taskforce generated an adult language paradigm algorithm for presurgical language assessment including the following tasks: Sentence Completion, Silent Word Generation, Rhyming, Object Naming, and/or Passive Story Listening. The pediatric algorithm includes the following tasks: Sentence Completion, Rhyming, Antonym Generation, or Passive Story Listening. DISCUSSION: Convergence of fMRI language paradigms across institutions offers the first step in providing a "Rosetta Stone" that provides a common reference point with which to compare and contrast the usefulness and reliability of fMRI data. From this common language task battery, future refinements and improvements are anticipated, particularly as objective measures of reliability become available. Some commonality of practice is a necessary first step to develop a foundation on which to improve the clinical utility of this field.


Asunto(s)
Algoritmos , Mapeo Encefálico/métodos , Lenguaje , Imagen por Resonancia Magnética/métodos , Cuidados Preoperatorios/normas , Adulto , Encefalopatías/cirugía , Mapeo Encefálico/normas , Niño , Femenino , Humanos , Imagen por Resonancia Magnética/normas , Masculino , Cuidados Preoperatorios/métodos , Reproducibilidad de los Resultados , Estados Unidos
6.
J Ethnopharmacol ; 199: 316-322, 2017 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-28057488

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: The latex of Ervatamia heyneana (Wall.) T. Cooke plant has been used for wound healing and various skin diseases by Indian tribes and folklore. AIM OF THE STUDY: To validate the scientific basis of heynein - a key protease of Ervatamia heyneana, in hemostasis and wound healing process. MATERIALS AND METHODS: The latex from E. heyneana was processed and subjected to two step purification. The purified heynein was assayed for proteolytic activity using casein as substrate and also attested by zymography. The inhibition studies confirmed the nature of heynein. Pure fibrinogen was used for fibrinogenolytic activity and citrated plasma was used for coagulant and fibrinolytic activities. The edema inducing action and hemorrhagic activity of heynein were assessed on mice model. RESULTS: The purified heynein exhibited proteolytic activity, which was confirmed by caseinolytic assay and zymography. The inhibition studies confirmed heynein to be a cysteine protease. Heynein showed complete hydrolysis of all the three subunits of human fibrinogen (Aα, Bß, γ). It exhibited strong pro-coagulant activity by reducing plasma clotting time from 248 to 39s at 40µg concentration. Heynein cleaved α polymer subunit in fibrin clot and did not induce edema and hemorrhage in mice models. The non-hemorrhagic nature was supported with histopathological studies of skin samples. CONCLUSION: Heynein displays strong pro-coagulant action associated with fibrin(ogen)olytic activity. This provides basis for the observed pharmacological action of Ervatamia heyneana and thereby justifies its use in folk medicine.


Asunto(s)
Apocynaceae , Proteasas de Cisteína/farmacología , Fibrinolíticos/farmacología , Hemostáticos/farmacología , Látex/farmacología , Extractos Vegetales/farmacología , Adulto , Animales , Proteasas de Cisteína/aislamiento & purificación , Proteasas de Cisteína/uso terapéutico , Fibrinógeno/metabolismo , Fibrinolíticos/aislamiento & purificación , Fibrinolíticos/uso terapéutico , Hemorragia/tratamiento farmacológico , Hemorragia/metabolismo , Hemostasis/efectos de los fármacos , Hemostasis/fisiología , Hemostáticos/aislamiento & purificación , Hemostáticos/uso terapéutico , Humanos , Látex/aislamiento & purificación , Látex/uso terapéutico , Masculino , Ratones , Corteza de la Planta , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/uso terapéutico , Trombosis/tratamiento farmacológico , Trombosis/metabolismo , Adulto Joven
8.
J La State Med Soc ; 167(3): 152, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-27159474

RESUMEN

Ewing's sarcoma is a rare, malignant bone tumor that occurs in children/young adults, and is known as the "small, round, blue cell tumor." The infrequency makes it a challenging diagnosis, especially when the typical patient characteristics are bypassed for decades.

9.
Clin Genet ; 86(5): 475-81, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24628545

RESUMEN

Anophthalmia/microphthalmia (A/M) is a developmental ocular malformation defined as complete absence or reduction in size of the eye. A/M is a heterogenous disorder with numerous causative genes identified; however, about half the cases lack a molecular diagnosis. We undertook whole exome sequencing in an A/M family with two affected siblings, two unaffected siblings, and unaffected parents; the ocular phenotype was isolated with only mild developmental delay/learning difficulties reported and a normal brain magnetic resonance imaging (MRI) in the proband at 16 months. No pathogenic mutations were identified in 71 known A/M genes. Further analysis identified a shared heterozygous mutation in COL4A1, c.2317G>A, p.(Gly773Arg) that was not seen in the unaffected parents and siblings. Analysis of 24 unrelated A/M exomes identified a novel c.2122G>A, p.(Gly708Arg) mutation in an additional patient with unilateral microphthalmia, bilateral microcornea and Peters anomaly; the mutation was absent in the unaffected mother and the unaffected father was not available. Mutations in COL4A1 have been linked to a spectrum of human disorders; the most consistent feature is cerebrovascular disease with variable ocular anomalies, kidney and muscle defects. This study expands the spectrum of COL4A1 phenotypes and indicates screening in patients with A/M regardless of MRI findings or presumed inheritance pattern.


Asunto(s)
Exoma/genética , Ojo/patología , Genes Dominantes , Microftalmía/genética , Mutación/genética , Adolescente , Secuencia de Aminoácidos , Anoftalmos/genética , Secuencia de Bases , Niño , Colágeno Tipo IV/química , Colágeno Tipo IV/genética , Análisis Mutacional de ADN , Familia , Femenino , Humanos , Lactante , Masculino , Datos de Secuencia Molecular , Linaje , Fenotipo
10.
Cell Death Dis ; 3: e428, 2012 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-23171848

RESUMEN

Poly-glutamine (polyQ) diseases are neurodegenerative disorders characterised by expanded CAG repeats in the causative genes whose proteins form inclusion bodies. Various E3 ubiquitin ligases are implicated in neurodegenerative disorders. We report that dysfunction of the SCF (Skp1-Cul1-F-box protein) complex, one of the most well-characterised ubiquitin ligases, is associated with pathology in polyQ diseases like Huntington's disease (HD) and Machado-Joseph disease (MJD). We found that Cullin1 (Cul1) and Skp1, core components of the SCF complex, are reduced in HD mice brain. A reduction in Cul1 levels was also observed in cellular HD model and fly models of both HD and MJD. We show that Cul1 is able to genetically modify mutant huntingtin aggregates because its silencing results in increased aggregate load in cultured cells. Moreover, we demonstrate that silencing dCul1 and dSkp1 in Drosophila results in increased aggregate load and enhanced polyQ-induced toxicity. Our results imply that reduced levels of SCF complex might contribute to polyQ disease pathology.


Asunto(s)
Enfermedad de Huntington/metabolismo , Enfermedad de Machado-Joseph/metabolismo , Péptidos/metabolismo , Proteínas Ligasas SKP Cullina F-box/metabolismo , Animales , Proteínas Cullin/genética , Proteínas Cullin/metabolismo , Drosophila/genética , Drosophila/metabolismo , Femenino , Humanos , Enfermedad de Huntington/genética , Enfermedad de Machado-Joseph/genética , Masculino , Ratones , Ratones Transgénicos , Proteínas Ligasas SKP Cullina F-box/genética
11.
Neuroradiol J ; 25(5): 528-32, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24029087

RESUMEN

Partial rhombencephalosynapsis in the presence of Chiari II malformation has been proposed as a "new abnormality of the hindbrain and spine". We describe a case of Chiari II malformation with imaging features mimicking partial rhombencephalosynapsis. Our case demonstrates how the imaging findings of Chiari II malformation can be confused with the above entity and highlights the differentiating features to help radiologists make an accurate diagnosis.

12.
Clin Exp Dermatol ; 37(1): 24-7, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21790726

RESUMEN

A 72-year-old man developed a generalized erythematous pustular eruption 11 weeks after commencing terbinafine. Clinically and histologically, the appearance was that of acute generalized exanthematous pustulosis (AGEP), and the disease was managed with topical preparations. Initial improvement was marred by relapse of acute pustulosis, now more in keeping with terbinafine-induced pustular psoriasis (PP), which was successfully treated with acitretin. This case highlights the difficulty of differentiating between AGEP and PP.


Asunto(s)
Pustulosis Exantematosa Generalizada Aguda/diagnóstico , Erupciones por Medicamentos/diagnóstico , Psoriasis/diagnóstico , Enfermedades Cutáneas Vesiculoampollosas/diagnóstico , Pustulosis Exantematosa Generalizada Aguda/inducido químicamente , Anciano , Antifúngicos/efectos adversos , Diagnóstico Diferencial , Humanos , Masculino , Naftalenos/efectos adversos , Psoriasis/inducido químicamente , Enfermedades Cutáneas Vesiculoampollosas/inducido químicamente , Terbinafina
13.
J Thromb Haemost ; 9(12): 2345-52, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21972893

RESUMEN

BACKGROUND: Atrial fibrillation (AF) is a common complication of coronary artery bypass grafting (CABG), and may have an inflammatory and/or thrombotic etiology. We sought to determine the expression of inflammatory (interleukin [IL]-6), thrombotic (tissue factor and von Willebrand factor [VWF]) and remodeling (matrix metalloproteinase [MMP]-9 and tissue inhibitor of metalloproteinase [TIMP]-1) markers by left atrial appendage (LAA) and right atrial appendage (RAA) tissue in the prediction of postoperative AF. We determined whether the tissue expression of markers of certain different pathophysiologic mechanisms predicted the development of AF after CABG. METHODS: LAA and RAA tissue was excised during CABG in 100 patients free of AF and inflammation. Tissue marker expression was quantified by immunohistochemistry and was related to 30-day postoperative AF. RESULTS: Overall, there were no significant differences in staining intensity of any marker between LAA tissue and RAA tissue. However, more intense expression of VWF by LAA tissue predicted the 30 patients with postoperative AF as compared with those free of AF (P = 0.006). IL-6, MMP-9 and TIMP-1 expression by RAA and LAA epicardial tissue was stronger than expression by endocardium or cardiomyocytes (all P < 0.025) but failed to predict AF. CONCLUSION: In this study, one of the largest to investigate tissue expression of pathophysiologic markers in relation to postoperative AF, we show that more intense expression of VWF by LAA tissue is a significant predictor of postoperative AF. This points towards a possible role of endothelial damage/dysfunction (as reflected by VWF changes) in the pathogenesis of postoperative AF.


Asunto(s)
Fibrilación Atrial/metabolismo , Biomarcadores/metabolismo , Endotelio/metabolismo , Inflamación/metabolismo , Miocardio/metabolismo , Trombosis/metabolismo , Anciano , Fibrilación Atrial/etiología , Puente de Arteria Coronaria/efectos adversos , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias
15.
Yao Xue Xue Bao ; 44(2): 175-80, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19408689

RESUMEN

A new spectrophotometric method has been examined for the determination of the tranexamic acid (TA) by derivatization with vanillin (VAN). The molar absorptivity of TA was calculated 25,160 L x mol(-1) x cm(-1) at lambdamax 354 nm and obeyed the Beer's law within 0.5-2.5 microg x mL(-1). The color reaction was highly stable and did not show any change in absorbance up to 24 h. The method was applied for the analysis of TA from capsules, injections and tooth pastes. The amounts of TA found in capsules, injections and tooth pastes of various pharmaceutical companies were observed with 249.0-250.9 mg/capsule, 249.3-250.7 mg/injection and 0.048%-0.049% in tooth pastes with relative standard deviation (RSD) 0.2%-5.0% (n = 3).


Asunto(s)
Antifibrinolíticos/análisis , Benzaldehídos/química , Preparaciones Farmacéuticas/química , Ácido Tranexámico/análisis , Cápsulas/química , Inyecciones , Espectrofotometría Ultravioleta , Pastas de Dientes/química
17.
Indian J Otolaryngol Head Neck Surg ; 60(1): 83-4, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23120510

RESUMEN

Nasopharyngeal carcinoma may present with bewildering arrays of signs & symptoms. Diagnosis often become difficult and requires a high degree of clinical suspicion for the disease. We here by present a case of 11 year old girl which have unusual presentation.

18.
Neuroradiol J ; 21(5): 678-82, 2008 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-24257011

RESUMEN

We describe a case of hemitrophy in a 12-year-old child presenting with seizures, hemiplegia and mental retardation. Hemiatrophy of one cerebral hemisphere is not frequently encountered in clinical practice. When this develops early in life (during the first two years), certain cranial changes like ipsilateral hypertrophy of the skull and sinuses occur. Asymmetry of cerebral hemispheric growth with atrophy on one side, ipsilateral osseous hypertrophy and hyper-pneumatization of sinuses with contralateral paresis are features of Dyke Davidoff Masson Syndrome (DDMS). Probably vascular occlusion was most important cause of hemiatrophy in our case.

19.
Br J Radiol ; 80(959): 898-901, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17908817

RESUMEN

Perforation of the gallbladder is an uncommon complication of acute cholecystitis that is associated with relatively high mortality. Symptoms and clinical signs can be indistinguishable from those of uncomplicated acute cholecystitis, leading to delayed diagnosis. We reviewed the clinical and imaging findings in 17 patients with gallbladder perforation confirmed at surgery.


Asunto(s)
Enfermedades de la Vesícula Biliar/diagnóstico por imagen , Adolescente , Adulto , Anciano , Colecistitis Aguda/complicaciones , Femenino , Enfermedades de la Vesícula Biliar/etiología , Enfermedades de la Vesícula Biliar/cirugía , Humanos , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad , Tomografía Computarizada por Rayos X
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