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1.
Ultrasound Obstet Gynecol ; 63(4): 481-488, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-37820067

RESUMO

OBJECTIVE: Placental vascular reactivity (PlVR) indicates the ability of the placental vasculature to match blood supply to fetal demand. Many pregnancy disorders alter the characteristics of PlVR, resulting in suboptimal oxygen delivery, although current understanding is limited by the lack of non-invasive, repeatable methods to measure PlVR in utero. Our objective was to quantify PlVR by measuring the placental response to transient changes in maternal carbon dioxide (CO2) using blood-oxygen-level-dependent (BOLD) magnetic resonance imaging (MRI). We hypothesized that PlVR will increase with gestational age to meet the changing demands of a growing fetus, and that PlVR will be driven by a maternal response to changes in CO2 concentration. METHODS: This was a cross-sectional study of 35 women with a healthy singleton pregnancy, of whom 31 were included in the analysis. The median gestational age was 32.6 (range, 22.6-38.4) weeks. Pregnant women were instructed to follow audiovisual breathing cues during a MRI scan. Maternal end-tidal CO2 (EtCO2) was measured concurrently with resting placental BOLD MRI for a total of 7-8 min. Preprocessing of magnetic resonance images consisted of manual delineation of placental anatomy and motion correction. In each placental voxel, vascular reactivity was computed using a coherence-weighted general linear model between MRI signal and EtCO2 stimulus. Global PlVR was computed as the mean of voxel-wise PlVR values across the placenta. RESULTS: PlVR, quantified by the placental response to induced, transient changes in maternal CO2, was consistently measured in utero using BOLD MRI. PlVR increased non-linearly with advancing gestational age (P < 0.001) and was higher on the fetal side of the placenta. PlVR was associated positively with fetal brain volume after accounting for gestational age. PlVR did not show any significant associations with maternal characteristics. CONCLUSIONS: We present, for the first time, a non-invasive paradigm to quantify PlVR in ongoing human pregnancies without the use of exogenous gases or contrast agents. Our findings suggest that PlVR is driven by a fetal response to changes in maternal CO2. Ease of translation to the clinical setting makes PlVR a promising biomarker for the identification and management of high-risk pregnancies. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Placenta , Complicações na Gravidez , Gravidez , Feminino , Humanos , Lactente , Placenta/irrigação sanguínea , Estudos Transversais , Dióxido de Carbono , Imageamento por Ressonância Magnética/métodos , Oxigênio
2.
J Perinatol ; 40(9): 1383-1388, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32546829

RESUMO

BACKGROUND: Quantitative MRI techniques help recognize delayed brain development in fetuses with congenital heart disease (CHD). Ventriculomegaly became an early marker of brain dysmaturity. OBJECTIVE: Evaluate longitudinally the cerebral ventricular and total brain volumes (TBV) in infants with CHD compared to normal neonates: testing the fetal brain dysmaturity and following its progression post operatively. STUDY DESIGN: Fetal and post-operative MRIs were obtained on fetuses/neonates with CHD requiring invasive intervention within the first month after birth. Volumetric measurement was done with ITK-SNAP and analyzed post-hoc. RESULTS: Ten cases were evaluated with a significant decrease in ventricular volumes from the fetal to the post-operative neonatal timepoint (p = 0.0297). Infants with HLHS had a significant increase postoperatively in their TBV (p = 0.0396). CONCLUSIONS: TBV increased post operatively inversely mirrored by the decrement of the ventricular volumes. This could be explained by the establishment an increase of brain blood flow after surgery.


Assuntos
Encéfalo , Cardiopatias Congênitas , Encéfalo/diagnóstico por imagem , Feto , Cardiopatias Congênitas/diagnóstico por imagem , Cardiopatias Congênitas/cirurgia , Humanos , Lactente , Recém-Nascido , Estudos Longitudinais , Imageamento por Ressonância Magnética
3.
Eur J Neurol ; 27(10): 1904-1912, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32432818

RESUMO

BACKGROUND AND PURPOSE: Amyotrophic lateral sclerosis (ALS) is a motor neuron disorder, although extra-motor degeneration is well recognized, especially in frontotemporal regions manifested as ALS with frontotemporal dementia (ALS-FTD). Previous neuroimaging studies of the brains of ALS-FTD patients have measured abnormalities of either grey matter (GM) or white matter (WM) structures but not of both together. Therefore, the aim was to evaluate both GM and WM in the same ALS-FTD patient using functional and structural neuroimaging. By doing so, insights could be gained into whether neurodegeneration in ALS-FTD is primarily a neuronopathy or axonopathy. METHODS: After high-resolution brain 2-deoxy-2-[18 F]fluoro-D-glucose (18 F-FDG) positron emission tomography (PET) and magnetic resonance imaging (MRI) scans were obtained in ALS-FTD patients and in age- and sex-matched neurological controls, changes in metabolic rate, cortical thickness (CT) and WM network analysis using graph theory were analyzed. RESULTS: Significant reductions in 18 F-FDG PET metabolism, CT and WM connections were observed in motor and extra-motor brain regions of ALS-FTD patients compared to controls. Both CT and underlying WM networks were abnormal in frontal, temporal, parietal and occipital lobes of ALS-FTD patients with 86 of 90 brain regions showing reductions of CT. CONCLUSION: Abnormalities in significantly fewer WM networks underlying the affected cortical regions suggest that neurodegeneration in brains of ALS-FTD patients is primarily a 'neuronopathy' rather than an 'axonopathy.'


Assuntos
Esclerose Lateral Amiotrófica , Demência Frontotemporal , Substância Branca , Esclerose Lateral Amiotrófica/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Demência Frontotemporal/diagnóstico por imagem , Glucose , Humanos , Imageamento por Ressonância Magnética , Tomografia por Emissão de Pósitrons , Substância Branca/diagnóstico por imagem
4.
ACS Appl Mater Interfaces ; 11(18): 17035-17049, 2019 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-30977630

RESUMO

With the increasing demand for highly efficient and durable catalysts, researchers have been doing extensive research to engineer the shape, size, and even phase (e.g., hcp or fcc Co) of individual catalyst nanoparticles, as well as the interface structure between the catalyst and support. In this work, cobalt oxides were deposited on ceria with rod-like morphology (CeO2NR) and cube-like morphology (CeO2NC) and silica with sphere-like morphology (SiO2NS) via a precipitation-deposition method to investigate the effects of support morphology, surface defects, support reducibility, and the metal-support interactions on redox and catalytic properties. XRD, Raman, XPS, BET, H2-TPR, O2-TPD, CO-TPD, TEM, and TPR/TPO cycling measurements have been mainly employed for catalysts characterization. Compared with CeO2NC and SiO2NS supports, as well as CeO2NC- and SiO2NS-supported cobalt catalysts, CeO2NR counterparts exhibited enhanced reducibility and CO oxidation performance at a lower temperature. Both the apparent activation energy and CO conversion demonstrated the following catalytic activity order: 10 wt % CoO x/CeO2NR > 10 wt % CoO x/CeO2NC > 10 wt % CoO x/SiO2NS. These results showed a strong support-dependent reducibility, CO oxidation, and redox cycling activity/stability of the as-prepared catalysts. Moreover, the significantly enhanced catalytic CO oxidation of the 10 wt % CoO x/CeO2NR catalyst indicated the vital role of CeO2NR support with rich surface oxygen vacancies, superior oxygen storage capacity and mobility, and excellent adsorption/desorption behavior of CO and O2 species.

6.
J Vet Intern Med ; 27(5): 1092-6, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23865401

RESUMO

BACKGROUND: Echocardiography is used for identification of cardiac tumors and presumptive diagnoses often are made based on the location of identified masses. OBJECTIVES: To determine the accuracy of echocardiographically based presumptive diagnoses of cardiac tumors when compared with clinicopathologic or histopathologic definitive diagnoses. ANIMALS: A total of 24 client-owned dogs having a cardiac mass on echocardiogram that was subsequently definitively diagnosed by cytology or histopathology. METHODS: Retrospective study. A Cardiac Veterinary Database search of animals seen at the University of Tennessee John and Ann Tickle Small Animal Hospital from 2006 to 2012 identified 24 dogs that fit the inclusion criteria. RESULTS: The presumptive diagnosis of chemodectoma, ectopic thyroid carcinoma, or lymphoma in cases with heart base masses was correct in 7/9 cases. The presumptive diagnosis of hemangiosarcoma in cases with right atrial masses was correct in 4/8 cases. Seven cases had an open diagnosis because of the unusual presentation on echocardiogram (ECG); various neoplasms were diagnosed in these animals, but hemangiosarcoma, chemodectoma, ectopic thyroid carcinoma, and lymphoma accounted for 6 of them. Pericardial effusion was seen in 10/24 cases. ECG abnormalities were seen in 8/24 cases. Survival ranged from <1 to >150 days. CONCLUSIONS AND CLINICAL IMPORTANCE: In this retrospective study, the presumptive diagnosis based on echocardiographic tumor location was only moderately accurate. Cardiac tumors that were considered unusual on echocardiogram were nonetheless frequently found to be the common cardiac tumor types seen in dogs.


Assuntos
Doenças do Cão/diagnóstico , Ecocardiografia/veterinária , Neoplasias Cardíacas/veterinária , Animais , Doenças do Cão/diagnóstico por imagem , Cães , Neoplasias Cardíacas/diagnóstico , Hemangiossarcoma/diagnóstico , Hemangiossarcoma/diagnóstico por imagem , Hemangiossarcoma/veterinária , Linfoma não Hodgkin/diagnóstico , Linfoma não Hodgkin/diagnóstico por imagem , Linfoma não Hodgkin/veterinária , Paraganglioma Extrassuprarrenal/diagnóstico , Paraganglioma Extrassuprarrenal/diagnóstico por imagem , Paraganglioma Extrassuprarrenal/veterinária , Estudos Retrospectivos , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/veterinária
7.
Indian J Dermatol ; 57(2): 149-51, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22615519

RESUMO

Secondary lymphangiomas or acquired lymphangiomas of vulva represent dilatation of upper dermal lymphatics following damage to previously normal deep lymphatics. They have been reported to occur following various infections, surgeries and radiotherapy which can cause damage to deep lymphatics.Treatment options in the management of secondary lymphangiomas include surgical resection, carbon dioxide laser vaporisation, sclerosing agents etc. We report two cases of secondary lymphangioma of vulva that followed radiotherapy for carcinoma of cervix. Both the patients were treated successfully by surgery.

8.
Brain Struct Funct ; 215(3-4): 255-63, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21046152

RESUMO

The waiting period of subplate evolution is a critical phase for the proper formation of neural connections in the brain. During this time, which corresponds to 15 to 24 postconceptual weeks (PCW) in the human fetus, thalamocortical and cortico-cortical afferents wait in and are in part guided by molecules embedded in the extracellular matrix of the subplate. Recent advances in fetal MRI techniques now allow us to study the developing brain anatomy in 3D from in utero imaging. We describe a reliable segmentation protocol to delineate the boundaries of the subplate from T2-W MRI. The reliability of the protocol was evaluated in terms of intra-rater reproducibility on a subset of the subjects. We also present the first 3D quantitative analyses of temporal changes in subplate volume, thickness, and contrast from 18 to 24 PCW. Our analysis shows that firstly, global subplate volume increases in proportion with the supratentorial volume; the subplate remained approximately one-third of supratentorial volume. Secondly, we found both global and regional growth in subplate thickness and a linear increase in the median and maximum subplate thickness through the waiting period. Furthermore, we found that posterior regions--specifically the occipital pole, ventral occipito-temporal region, and planum temporale--of the developing brain underwent the most statistically significant increases in subplate thickness. During this period, the thickest region was the developing somatosensory/motor cortex. The subplate growth patterns reported here may be used as a baseline for comparison to abnormal fetal brain development.


Assuntos
Desenvolvimento Fetal/fisiologia , Feto/embriologia , Córtex Motor/embriologia , Neurônios Aferentes/citologia , Córtex Somatossensorial/embriologia , Adulto , Mapeamento Encefálico , Feminino , Idade Gestacional , Humanos , Imageamento Tridimensional , Imageamento por Ressonância Magnética , Morfogênese , Córtex Motor/citologia , Gravidez , Reprodutibilidade dos Testes , Córtex Somatossensorial/citologia
10.
Artigo em Inglês | MEDLINE | ID: mdl-17642934

RESUMO

Lipodystrophy and associated metabolic abnormalities are being increasingly recognized as complications of juvenile dermatomyositis. We report one such case.

11.
Artigo em Inglês | MEDLINE | ID: mdl-17656982

RESUMO

Pseudo Kaposi's sarcoma is a rare vascular lesion, usually associated with arterio venous malformations of the Parker Weber type, and only occasionally with Klippel Trenaunay syndrome per se. We report one such case.

12.
Blood ; 80(1): 153-61, 1992 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-1611082

RESUMO

Glycoprotein Ib alpha (GpIb alpha) is a platelet membrane Gp that binds von Willebrand factor and mediates platelet adhesion to subendothelium. We have found both GpIb alpha mRNA and protein in human umbilical vein endothelial cells (HUVEC). In previously published work we reported that combined treatment with interferon-gamma (IFN-gamma) and tumor necrosis factor-alpha (TNF-alpha) markedly increased the GpIb alpha mRNA level in HUVEC. We have now documented that TNF-alpha alone induces GpIb alpha mRNA and protein expression, studied the kinetics of this response, and investigated potential mechanisms of the TNF-alpha effect. GpIb alpha mRNA induction by TNF-alpha is detectable as early as 2 hours after exposure to this cytokine, and reaches a maximal level after 20 to 24 hours. Using a nuclear run-on assay we found that GpIb alpha gene transcription is increased approximately 10-fold after 2 hours of TNF-alpha treatment. Furthermore, using two monoclonal antibodies that recognize different epitopes of GpIb alpha, we found that the protein expression in endothelial cells is markedly increased by TNF-alpha. Interleukin-1 (IL-1) and the phorbol ester phorbol myristate acetate, which mimic many effects of TNF-alpha on endothelial cells, have no effect on endothelial or human erytholeukemia (HEL)-cell GpIb alpha mRNA. TNF-alpha treatment for 24 hours increases the HEL cell GpIb alpha mRNA level approximately fourfold, showing a time- and dose-dependent effect similar to that seen in HUVEC. TNF-alpha-induced GpIb alpha mRNA and protein synthesis may play a role in mediating platelet or other cell interaction with activated endothelium. Unlike other endothelial pro-thrombotic and pro-adhesive proteins induced by TNF-alpha, GpIb alpha is not induced by IL-1 treatment, which suggests a novel pathway for induction of this protein.


Assuntos
Endotélio Vascular/metabolismo , Leucemia Eritroblástica Aguda/metabolismo , Glicoproteínas da Membrana de Plaquetas/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Western Blotting , Células Cultivadas , Expressão Gênica/efeitos dos fármacos , Humanos , Técnicas In Vitro , Interferon gama/farmacologia , Interleucina-1/farmacologia , Glicoproteínas da Membrana de Plaquetas/genética , RNA Mensageiro/genética , Proteínas Recombinantes , Acetato de Tetradecanoilforbol/farmacologia , Fatores de Tempo
13.
Ann Saudi Med ; 11(1): 97-9, 1991 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17588066
14.
Surg Gynecol Obstet ; 170(2): 165-6, 1990 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2300870

RESUMO

A technique for resection of irreducible, gangrenous jejunogastric intussusception is presented. In comparison with previously described resection procedures involving division of the stoma, dismantling of the gastrojejunostomy or higher gastrectomy, in situ resection is simple and safe.


Assuntos
Intussuscepção/cirurgia , Doenças do Jejuno/cirurgia , Gastropatias/cirurgia , Anastomose Cirúrgica/métodos , Estudos de Avaliação como Assunto , Humanos
15.
Anc Sci Life ; 6(3): 138-47, 1987 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22557563

RESUMO

68 cases of epilepsy are studied here for assessing the doshic dominance to understand prognosis with a view to supplement the treatment with some doshahara compounds or drugs. Most of the cases studied or vata or pitta dominant cases, thereby, requiring vatahara or pittahara treatment.

16.
Anc Sci Life ; 7(2): 110-5, 1987 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22557598

RESUMO

28 patients undergoing treatment for Cancer and 57 normal adults are studied for their Prakriti (constitution and temperature) to find out whether there is any difference in the prakriti pattern of Cancer patients when compared with that of normal volunteers. Pitta dominance is found in the prakriti pattern of Cancer patients followed by Kapha dominance. The prognostic therapeutic utility and scope of the knowledge of prakriti patterns are also discussed in this paper.

17.
Anc Sci Life ; 5(4): 262, 1986 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22557536
18.
Arch Dis Child ; 60(12): 1122-7, 1985 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-4091577

RESUMO

A neurodevelopmental screen in the medical examination of 3750 school entrants with a mean age of 5 years 4 months was validated as a predictor of coordination and communication difficulties. Class teachers of 6, 7, and 8 year olds completed a questionnaire about motor and communication success and difficulty in school activities. Below average ratings on the neurodevelopmental screen were associated with later problems in school activities. The findings, reported to all head teachers, suggest some approaches to intervention in school. The neurodevelopmental screen contributes to early assessment of special education needs of clumsy children.


Assuntos
Desenvolvimento Infantil , Transtornos da Comunicação/prevenção & controle , Programas de Rastreamento/métodos , Destreza Motora , Serviços de Saúde Escolar , Fatores Etários , Criança , Pré-Escolar , Inglaterra , Feminino , Humanos , Masculino
19.
Anc Sci Life ; 2(4): 194-8, 1983 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22556981

RESUMO

The effect of an Ayurvedic preparation consisting of Swasakutara, Curcuma longa (Haridra) and Withania somnifera (Asvagandha) is accessed in 12 patients of tropical eosinphilia. The modern control drug Hetrazan is used in another batch of 11 patients for comparison. The Ayurvedic compound causes complete relief of most of the clinical signs and symptoms associated with the disease and reduces E.S.R. significantly. However the drug has no effect on the level of circulating eosinophils.

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