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1.
Eur J Neurol ; 31(6): e16277, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38497590

RESUMO

BACKGROUND AND PURPOSE: Patients who underwent red blood cell (RBC) transfusion from donors who later developed multiple spontaneous intracerebral hemorrhages (ICHs) have recently been identified to have increased risk of ICH themselves. This increased risk of ICH was hypothesized to be related to iatrogenic cerebral amyloid angiopathy (iCAA) transmission. Two cases are presented who had RBC transfusion as an infant and presented with CAA at a relatively young age decades later. METHOD: Cases were identified by prospectively asking all patients at our CAA outpatient clinic (November 2023 to January 2024) about a medical history with RBC transfusion or history with a high likelihood for RBC transfusion (e.g., hemolytic disease, trauma with massive hemorrhage). Eligible patients were all diagnosed with CAA, CAA with concomitant hypertensive arteriopathy or iCAA, and without hereditary CAA. RESULTS: Between November 2023 and January 2024, 2/35 (6%, 95% confidence interval 2%-19%) outpatient clinic patients had a history of RBC transfusion and none had a high likelihood medical history. The cases presented at age 47 and 57 and had already developed severe CAA. CONCLUSIONS: Red blood cell transfusion might be a possible mechanism for iCAA; however, further prospective data collection and experimental evidence concerning blood transmission of amyloid-ß are needed.


Assuntos
Angiopatia Amiloide Cerebral , Transfusão de Eritrócitos , Humanos , Transfusão de Eritrócitos/efeitos adversos , Angiopatia Amiloide Cerebral/complicações , Pessoa de Meia-Idade , Masculino , Feminino , Estudos Prospectivos , Estudos de Coortes
2.
Mikrochim Acta ; 190(2): 64, 2023 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-36690871

RESUMO

The fabrication of SERS substrate by gold nanoparticle-decorated polyvinyl alcohol electrospun nanofibers which has been used to detect trace sensing of two widely used poultry antibiotics doxycycline hydrochloride and enrofloxacin is demonstrated. The performance of the backscattered Raman signals from the proposed SERS substrate has been initially evaluated with two standard Raman active compounds namely malachite green and rhodamine-6G. The limit of detection of the proposed substrate is estimated to be 7.32 nM. Following this, the usability of the proposed SERS substrate has been demonstrated through the detection of the aforementioned antibiotics in chicken meat samples. The presence of antibiotics in chicken meat sample has been validated with the standard analytical tool of liquid chromatography-mass spectrometry and the results were compared with the proposed sensing technique. Further, principal component analysis has been performed to classify the antibiotics that are present in the field-collected meat samples.


Assuntos
Nanopartículas Metálicas , Nanofibras , Animais , Nanopartículas Metálicas/química , Ouro/química , Galinhas , Antibacterianos , Nanofibras/química , Análise Espectral Raman/métodos , Carne
3.
Analyst ; 147(17): 3817-3821, 2022 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-35916063

RESUMO

A nanofluidic device with spatially, non-uniformly distributed gate electrodes is reported. In this nanofluidic architecture, multiple nanochannels connect microfluidic reservoirs for the formation of a planar, hybrid microfluidic-nanofluidic device. The gate electrodes are individually addressable, fluidically isolated, and enable a non-uniform electric field distribution within the nanochannels permitting the capture of proteins and a local increase in their concentration. The removal of the gate potential allows the model protein, bovine serum albumin, to move away from the electrodes after concentration at the electrodes for the release of the captured protein. A maximum increase in the protein concentration of nearly an order of magnitude was observed as evaluated by fluorescence intensity.


Assuntos
Microfluídica , Nanotecnologia , Eletricidade , Dispositivos Lab-On-A-Chip , Soroalbumina Bovina
4.
Cryo Letters ; 43(1): 10-17, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35315865

RESUMO

BACKGROUND: Vitrification increases the production of reactive oxygen species (ROS) and the antioxidants in the vitrification solution may be beneficial by reducing excessive ROS production. OBJECTIVE: To evaluate the effect of retinol supplementation in vitrification solution on viability, apoptosis and development-related gene expression in vitrified sheep preantral follicles. MATERIALS AND METHODS: Preantral follicles were isolated and randomly assigned into one of five groups: Group1, control fresh preantral follicles; Group 2, vitrification treatment; Group 3, vitrification + 2 µM retinol; Group 4, vitrification + 5 µM retinol; Group 5, vitrification + 10 µM retinol. Preantral follicles were placed in vitrification solutions and then plunged into liquid nitrogen (-196°C). After a week, the follicles were thawed and analyzed for follicular viability by trypan blue exclusion method and for gene expression. RESULTS: Vitrification with 5 µM retinol positively affected viability in comparison with vitrification without retinol (P < 0.05). There was no significant difference in viability among the Group 1, Group 2, Group 3 and Group 5. Expression of apoptotic genes BAX and Casp 3 were higher in the vitrified group, and vitrification with 5 µM retinol (Group 4) is comparable to the control fresh. Expressions of other apoptosis-related genes (i.e., BCL2L1, BAD and BAK) showed significant difference between the control fresh group and the vitrification group with 5 µM retinol. Expression of Annexin5 was also significantly different among various groups. The expression of development competence genes GDF-9 and BMP-15 were higher (P < 0.05) in the Group vitrified with 5 µM retinol. CONCLUSION: The supplementation of 5 µM retinol in vitrification solution was beneficial for the vitrification of ovine preantral follicles.


Assuntos
Vitamina A , Vitrificação , Animais , Apoptose , Criopreservação/métodos , Criopreservação/veterinária , Feminino , Folículo Ovariano , Ovinos , Vitamina A/farmacologia
5.
Reprod Domest Anim ; 56(11): 1446-1455, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34449946

RESUMO

The present study evaluated the effect of supplementation of retinol in the vitrification solution on the viability, apoptosis and development-related gene expression in vitrified buffalo preantral follicles. Preantral follicles isolated from cortical slices of ovaries were randomly assigned into three groups: Group1-Control fresh preantral follicles; Group 2-Vitrification treatment (Vitrification solution 1 (VS1) -TCM-199 + 25 mM HEPES + Foetal bovine serum (FBS) 10%, Ethylene glycol (EG): 10%, Dimethyl sulphoxide (DMSO): 10%, Sucrose-0.3 M for 4 min; VS2- TCM-199 + 25 mM HEPES + FBS10%, EG:25%, DMSO: 25%, Sucrose:0.3 M for 45 s); Group3-vitrification treatment +5 µM of Retinol. Preantral follicles were placed in corresponding vitrification medium and plunged into liquid nitrogen (-196°C). After a week, the follicles were thawed and analysed for follicular viability and gene expression. There was no significant difference in the viability rates among the Group 1(Fresh preantral follicles) (91.46 ± 2.39%), Group 2 (89.59 ± 2.46%) and Group 3 (87.19 ± 4.05%). There was a significantly (p < .05) higher mRNA expression of BCL2L1, GDF-9 and BMP-15 in the vitrification + retinol group compared with the control group. There was a significantly (p < .05) higher expression of Caspase-3 and Annexin-5 in the vitrification group and Vitrification + retinol group compared with control group of follicles. It is concluded that the supplementation of 5 µM of Retinol in Vitrification solution was an efficient vitrification procedure for the vitrification of buffalo preantral follicles.


Assuntos
Antioxidantes/farmacologia , Criopreservação/veterinária , Folículo Ovariano/efeitos dos fármacos , Vitamina A/farmacologia , Animais , Apoptose , Búfalos , Criopreservação/métodos , Feminino , Regulação da Expressão Gênica , Folículo Ovariano/crescimento & desenvolvimento , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Vitrificação
6.
Eur Radiol ; 29(7): 3496-3505, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30734849

RESUMO

OBJECTIVES: Experimental models have provided compelling evidence for the existence of neural networks in temporal lobe epilepsy (TLE). To identify and validate the possible existence of resting-state "epilepsy networks," we used machine learning methods on resting-state functional magnetic resonance imaging (rsfMRI) data from 42 individuals with TLE. METHODS: Probabilistic independent component analysis (PICA) was applied to rsfMRI data from 132 subjects (42 TLE patients + 90 healthy controls) and 88 independent components (ICs) were obtained following standard procedures. Elastic net-selected features were used as inputs to support vector machine (SVM). The strengths of the top 10 networks were correlated with clinical features to obtain "rsfMRI epilepsy networks." RESULTS: SVM could classify individuals with epilepsy with 97.5% accuracy (sensitivity = 100%, specificity = 94.4%). Ten networks with the highest ranking were found in the frontal, perisylvian, cingulo-insular, posterior-quadrant, thalamic, cerebello-thalamic, and temporo-thalamic regions. The posterior-quadrant, cerebello-thalamic, thalamic, medial-visual, and perisylvian networks revealed significant correlation (r > 0.40) with age at onset of seizures, the frequency of seizures, duration of illness, and a number of anti-epileptic drugs. CONCLUSIONS: IC-derived rsfMRI networks contain epilepsy-related networks and machine learning methods are useful in identifying these networks in vivo. Increased network strength with disease progression in these "rsfMRI epilepsy networks" could reflect epileptogenesis in TLE. KEY POINTS: • ICA of resting-state fMRI carries disease-specific information about epilepsy. • Machine learning can classify these components with 97.5% accuracy. • "Subject-specific epilepsy networks" could quantify "epileptogenesis" in vivo.


Assuntos
Cerebelo/diagnóstico por imagem , Epilepsia do Lobo Temporal/diagnóstico , Aprendizado de Máquina , Imageamento por Ressonância Magnética/métodos , Tálamo/diagnóstico por imagem , Adulto , Cerebelo/fisiopatologia , Eletroencefalografia , Feminino , Humanos , Masculino , Tálamo/fisiopatologia , Adulto Jovem
7.
Radiographics ; 39(2): 321-343, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30735469

RESUMO

Orthotopic heart transplant (OHT) is the treatment of choice for end-stage heart disease. As OHT use continues and postoperative survival increases, multimodality imaging evaluation of the transplanted heart will continue to increase. Although some of the imaging is performed and interpreted by cardiologists, a substantial proportion of images are read by radiologists. Because there is little to no consensus on a systematic approach to patients after OHT, radiologists must become familiar with common normal and abnormal posttreatment imaging features. Intrinsic transplant-related complications may be categorized on the basis of time elapsed since transplant into early (0-30 days), intermediate (1-12 months), and late (>12 months) stages. Although there can be some overlap between stages, it remains helpful to consider the time elapsed since surgery, because some complications are more common at certain stages. Recognition of differing OHT surgical techniques and their respective postoperative imaging features helps to avoid image misinterpretation. Expected early postoperative findings include small pneumothoraces, pleural effusions, pneumomediastinum, pneumopericardium, postoperative atelectasis, and an enlarged cardiac silhouette. Early postoperative complications also can include sternal dehiscence and various postoperative infections. The radiologist's role in the evaluation of allograft failure and rejection, endomyocardial biopsy complications, cardiac allograft vasculopathy, and posttransplant malignancy is highlighted. Because clinical manifestations of disease may be delayed in transplant recipients, radiologists often recognize postoperative complications on the basis of imaging and may be the first to suggest a specific diagnosis and thus positively affect patient outcomes. Online supplemental material is available for this article. ©RSNA, 2019.


Assuntos
Transplante de Coração/métodos , Coração/diagnóstico por imagem , Miocárdio/patologia , Complicações Pós-Operatórias/diagnóstico por imagem , Radiografia/métodos , Ecocardiografia , Feminino , Rejeição de Enxerto/diagnóstico por imagem , Rejeição de Enxerto/patologia , Humanos , Masculino , Pericardite/diagnóstico por imagem , Período Pós-Operatório , Neoplasias Torácicas/diagnóstico por imagem , Tomografia Computadorizada por Raios X
8.
Analyst ; 143(18): 4256-4266, 2018 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-30028451

RESUMO

Selective permeation of water vapor over liquid phase water through hydrophobic conduits finds broad use in separation processes, including desalination and membrane distillation. The tangential momentum accommodation coefficient (TMAC), a fundamental parameter that dictates momentum changes to a molecule colliding with a wall remains unknown for water vapor at room temperature and pressure conditions. Here, a nanofluidic platform with tunable hydrophobic regions that selectively barricaded flow of liquid water was patterned within glass nanochannels. The surface functionalization with an alkyltrichlorosilane led to either a fluoride or a methyl terminal group generating partially hydrophobic regions along the length of the nanochannels. Differential osmotic pressure solutions on either side of the hydrophobic region cause an isothermal evaporation-condensation process, which drives net water vapor transport from higher to lower vapor pressure solution, similar to osmotic distillation. Water vapor transport under such conditions for the 80 nm deep nanochannels was in the transitional regime with the Knudsen number ∼O(1). The TMAC was estimated experimentally to be of the order of 10-4-10-3 for both the hydrophobic coatings leading to a near-elastic collision of H2O molecules with the nanochannel walls. Use of the low TMAC surfaces was evaluated in two proof-of-concept technology demonstrations: (1) osmotic distillation using hyper-saline (brine) 3 M Utica shale flowback water as both the feed and draw and (2) separation of trace amounts of toluene and chloroform from water at high flux and selectivity. The results reported here likely provide new insights in designing hydrophilic-hydrophobic junctions for nanoscale liquid/vapor fluid transport with enhanced flux and selectivity.

9.
Anal Chem ; 89(3): 1593-1601, 2017 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-28208271

RESUMO

Surface charge governs nanoscale aqueous electrolyte transport, both in engineered analytical systems and in biological entities such as ion channels and ion pumps as a function of ion type and concentration. Embedded electrodes in a nanofluidic channel, isolated from the fluid in the channel by a dielectric layer, act as active, tunable gates to systematically modify local surface charge density at the interface between the nanochannel surface and the aqueous electrolyte solution, causing significant changes in measured nanochannel conductance. A systematic comparison of transport of monovalent electrolytes [potassium chloride (KCl), sodium chloride (NaCl)], 2:1 electrolytes [magnesium chloride (MgCl2), calcium chloride (CaCl2)], and electrolyte mixtures (KCl + CaCl2) through a gated nanofluidic device was performed. Ion-surface interactions between divalent Ca2+ and Mg2+ ions and the nanochannel walls reduced the native surface charge density by up to ∼4-5 times compared to the monovalent cations. In electrolyte mixtures, Ca2+ was the dominating cation with nanochannel conductance independent of KCl concentration. Systematic changes in local electrostatic surface state induced by the gate electrode are impacted by the divalent cation-surface interactions, limiting modulation of the local surface potential by the gate electrode and resulting in cation dependent nanoscale ion transport as seen through conductance measurements and numerical models.

10.
Biochim Biophys Acta Gen Subj ; 1861(1 Pt A): 3039-3052, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27721046

RESUMO

BACKGROUND: Gold nanorods, by virtue of surface plasmon resonance, convert incident light energy (NIR) into heat energy which induces hyperthermia. We designed unique, multifunctional, gold nanorod embedded block copolymer micelle loaded with GW627368X for targeted drug delivery and photothermal therapy. METHODS: Glutathione responsive diblock co-polymer was synthesized by RAFT process forming self-assembled micelle on gold nanorods prepared by seed mediated method and GW627368X was loaded on to the reduction responsive gold nanorod embedded micelle. Photothermal therapy was administered using cwNIR laser (808nm; 4W/cm2). Efficacy of nanoformulated GW627368X, photothermal therapy and combination of both were evaluated in vitro and in vivo. RESULTS: In response to photothermal treatment, cells undergo regulated, patterned cell death by necroptosis. Combining GW627368X with photothermal treatment using single nanoparticle enhanced therapeutic outcome. In addition, these nanoparticles are effective X-ray CT contrast agents, thus, can help in monitoring treatment. CONCLUSION: Reduction responsive nanorod embedded micelle containing folic acid and lipoic acid when treated on cervical cancer cells or tumour bearing mice, aggregate in and around cancer cells. Due to high glutathione concentration, micelles degrade releasing drug which binds surface receptors inducing apoptosis. When incident with 808nm cwNIR lasers, gold nanorods bring about photothermal effect leading to hyperthermic cell death by necroptosis. Combination of the two modalities enhances therapeutic efficacy by inducing both forms of cell death. GENERAL SIGNIFICANCE: Our proposed treatment strategy achieves photothermal therapy and targeted drug delivery simultaneously. It can prove useful in overcoming general toxicities associated with chemotherapeutics and intrinsic/acquired resistance to chemo and radiotherapy.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Ouro/química , Hipertermia Induzida , Micelas , Nanotubos/química , Neoplasias/terapia , Fototerapia , Polímeros/química , Animais , Materiais Biocompatíveis/farmacologia , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Meios de Contraste/química , Liberação Controlada de Fármacos , Endocitose/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Isoindóis/farmacologia , Camundongos , Nanotubos/ultraestrutura , Polímeros/síntese química , Espectrofotometria Ultravioleta , Espectroscopia de Luz Próxima ao Infravermelho , Sulfonamidas/farmacologia , Raios X
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