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1.
RSC Adv ; 14(9): 6367-6373, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38380233

RESUMO

N1-Alkyl indazoles are a ubiquitous and privileged motif within medicinal chemistry, yet methods to selectively furnish N1-alkyl indazoles with simple alkyl side chains remain sparse. Herein, negative data from high-throughput experimentation (HTE) enabled a confident pivot of resource from continued optimisation to the development of an alternative reaction. This workflow culminated in a methodology for the synthesis of N1-alkyl indazoles. The procedure is highly selective for N1-alkylation, practical, and broad in scope, with no N2-alkyl products detected at completion. Mechanistic understandings were consistent with attributing the high selectivity to thermodynamic control. Additional data-driven process development led to this reaction being safely demonstrated on a 100 g scale, with potential for further scale up. This study highlights pragmatic principles followed to develop a necessitated methodology, suitable for large scale manufacture.

2.
J Am Chem Soc ; 144(10): 4572-4584, 2022 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-35230845

RESUMO

Asymmetric catalytic azidation has increased in importance to access enantioenriched nitrogen containing molecules, but methods that employ inexpensive sodium azide remain scarce. This encouraged us to undertake a detailed study on the application of hydrogen bonding phase-transfer catalysis (HB-PTC) to enantioselective azidation with sodium azide. So far, this phase-transfer manifold has been applied exclusively to insoluble metal alkali fluorides for carbon-fluorine bond formation. Herein, we disclose the asymmetric ring opening of meso aziridinium electrophiles derived from ß-chloroamines with sodium azide in the presence of a chiral bisurea catalyst. The structure of novel hydrogen bonded azide complexes was analyzed computationally, in the solid state by X-ray diffraction, and in solution phase by 1H and 14N/15N NMR spectroscopy. With N-isopropylated BINAM-derived bisurea, end-on binding of azide in a tripodal fashion to all three NH bonds is energetically favorable, an arrangement reminiscent of the corresponding dynamically more rigid trifurcated hydrogen-bonded fluoride complex. Computational analysis informs that the most stable transition state leading to the major enantiomer displays attack from the hydrogen-bonded end of the azide anion. All three H-bonds are retained in the transition state; however, as seen in asymmetric HB-PTC fluorination, the H-bond between the nucleophile and the monodentate urea lengthens most noticeably along the reaction coordinate. Kinetic studies corroborate with the turnover rate limiting event resulting in a chiral ion pair containing an aziridinium cation and a catalyst-bound azide anion, along with catalyst inhibition incurred by accumulation of NaCl. This study demonstrates that HB-PTC can serve as an activation mode for inorganic salts other than metal alkali fluorides for applications in asymmetric synthesis.


Assuntos
Azidas , Fluoretos , Álcalis , Ânions/química , Catálise , Hidrogênio , Ligação de Hidrogênio , Cinética , Azida Sódica
3.
Cureus ; 13(8): e17046, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34522524

RESUMO

Denosumab is a humanized monoclonal antibody that binds RANKL to inhibit osteoclast activity. It is indicated for the prevention of skeletal-related events (SRE) in patients with solid tumors who have bone metastasis and in patients with multiple myeloma. Hypocalcemia is one of the known side effects of denosumab, which can be prevented with calcium supplementation. We present a case of a 72-year-old male with diagnosed metastatic prostate cancer who had received one dose of denosumab 10 days prior to presentation with fatigue, insomnia, and somnolence. His labs showed severe (Grade 4) hypocalcemia, which improved with intravenous calcium supplementation. This case highlights a known but life-threatening side effect of denosumab and the potential need for prolonged calcium monitoring in patients placed on the drug.

4.
Clin Kidney J ; 12(2): 196-205, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30976396

RESUMO

BACKGROUND: Eculizumab, a terminal complement inhibitor, is approved for atypical haemolytic uraemic syndrome (aHUS) to inhibit complement-mediated thrombotic microangiopathy (TMA). METHODS: In five parent studies, eculizumab effectively prevented TMA and improved renal and haematologic outcomes in patients with aHUS; therefore, these patients could enrol in this long-term, prospective, observational and multicentre study. The primary endpoint was the TMA manifestation rate off and on eculizumab post-parent study. Post hoc analyses evaluated rates during labelled versus non-labelled dosing regimens, and in those with versus without identified complement abnormalities. Serious targeted treatment-emergent adverse events (TEAEs) were evaluated. RESULTS: Of 87 patients in the current study, 39 and 76 had off- and on-treatment periods, respectively; 17 (44%) with off periods reinitiated eculizumab. TMA manifestation rate per 100 patient-years was 19.9 off and 7.3 on treatment [hazard ratio (HR), 4.7; P = 0.0008]; rates were highest off treatment and lowest during labelled regimens. TMA manifestations with hospitalizations/serious AEs occurred more frequently off versus on treatment. TMA rates were higher among patients with identified complement abnormalities (HR, 4.5; P = 0.0082). Serious targeted TEAEs occurred at similar rates off and on treatment. CONCLUSIONS: As expected, patients with aHUS have increased risk of TMA manifestations after discontinuation of eculizumab or in the setting of non-labelled eculizumab dosing. Collectively, results show that maintaining eculizumab treatment minimizes risk of TMA, particularly in patients with identified complement abnormalities. Future studies are needed to further characterize TMA and longer term outcomes on labelled or non-labelled eculizumab regimens and after discontinuation of treatment.

5.
BMC Nephrol ; 20(1): 125, 2019 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-30971227

RESUMO

BACKGROUND: There are limited long-term outcome data in eculizumab-treated patients with atypical hemolytic uremic syndrome (aHUS). We report final results from the largest prospective, observational, multicenter study of patients with aHUS treated with eculizumab. METHODS: Patients with aHUS who participated in any of five parent eculizumab trials and received at least one eculizumab infusion were eligible for enrollment in a long-term follow-up study. Rates of thrombotic microangiopathy (TMA) manifestations off versus on eculizumab were evaluated. Additional endpoints included change from baseline estimated glomerular filtration rate (eGFR), long-term renal outcomes, and serious targeted treatment-emergent adverse events. RESULTS: Among 93 patients (0-80 years of age), 51 (55%) remained on eculizumab and 42 (45%) discontinued; for those who discontinued, 21 (50%) reinitiated therapy. Patients who reinitiated eculizumab had similar baseline clinical characteristics to patients who remained on eculizumab, with higher likelihood of genetic/autoimmune complement abnormalities, more prior TMAs, and longer disease course versus those who did not reinitiate. Mean eGFR improved rapidly and remained stable for up to 6 years on eculizumab. In patients who discontinued, there was a trend toward decreasing renal function over time from discontinuation. Additionally, off-treatment TMA manifestation rates were higher in those aged < 18 years at diagnosis, with identified genetic/autoimmune complement abnormalities, or history of multiple TMAs prior to eculizumab initiation. The safety profile was consistent with previous studies. Three definite and one possible meningococcal infections related to eculizumab were reported and resolved with treatment. Three deaths unrelated to eculizumab were reported. CONCLUSIONS: The current study confirms the efficacy and safety of eculizumab in aHUS, particularly with regard to long-term renal function and TMA events. Pediatric age at disease onset and presence of genetic or autoimmune complement abnormalities are risk factors for TMA events off treatment. Overall, patients who discontinue eculizumab may be at risk for additional TMA manifestations and renal function decreases. Discontinuation of eculizumab, with careful monitoring, is an option in select patients with consideration of patient preference, organ function normalization, and risk factors for relapse, including mutational analysis, age of onset, and history of multiple TMA episodes. TRIAL REGISTRATION: ClinicalTrials.gov NCT01522170 , January 31, 2012.


Assuntos
Anticorpos Monoclonais Humanizados , Síndrome Hemolítico-Urêmica Atípica/tratamento farmacológico , Efeitos Adversos de Longa Duração , Microangiopatias Trombóticas , Adolescente , Adulto , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/efeitos adversos , Síndrome Hemolítico-Urêmica Atípica/complicações , Síndrome Hemolítico-Urêmica Atípica/diagnóstico , Síndrome Hemolítico-Urêmica Atípica/epidemiologia , Criança , Inativadores do Complemento/administração & dosagem , Inativadores do Complemento/efeitos adversos , Feminino , Seguimentos , Taxa de Filtração Glomerular , Humanos , Cooperação Internacional , Efeitos Adversos de Longa Duração/diagnóstico , Efeitos Adversos de Longa Duração/epidemiologia , Efeitos Adversos de Longa Duração/etiologia , Masculino , Conduta do Tratamento Medicamentoso , Avaliação de Processos e Resultados em Cuidados de Saúde , Microangiopatias Trombóticas/diagnóstico , Microangiopatias Trombóticas/epidemiologia , Microangiopatias Trombóticas/etiologia
6.
J Obstet Gynaecol Res ; 44(4): 801-805, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29297962

RESUMO

Labial agglutination has rarely been reported in postmenopausal women and its treatment has been based on experience with prepubertal girls. We describe an 83-year-old woman who presented with labial agglutination and severe urinary incontinence. She had been treated intermittently with a topical estrogen cream for 3 years, but her symptoms persisted. Surgery was performed and her urinary incontinence was instantly resolved. Incidental vaginal low-grade squamous intraepithelial neoplasia was noted. Later, the lesion progressed and was confirmed to be condyloma acuminata. No recurrence of labial agglutination was noted 3 months after the surgery. We emphasize that surgical intervention should be the first consideration for labial agglutination with urinary symptoms in postmenopausal women. This case also highlights that surgery can not only resolve patients' symptoms early, but can also enable access to the region for essential gynecologic procedures.


Assuntos
Pós-Menopausa , Lesões Intraepiteliais Escamosas Cervicais/diagnóstico , Incontinência Urinária/cirurgia , Neoplasias Vaginais/diagnóstico , Doenças da Vulva/cirurgia , Idoso de 80 Anos ou mais , Feminino , Humanos
7.
Transpl Int ; 30(12): 1275-1283, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28801959

RESUMO

Atypical haemolytic uraemic syndrome (aHUS) often leads to end-stage renal disease (ESRD) and kidney transplantation; graft loss rates are high due to disease recurrence. A post hoc analysis of four prospective clinical trials in aHUS was performed to evaluate eculizumab, a terminal complement inhibitor, in patients with native or transplanted kidneys. The trials included 26-week treatment and extension periods. Dialysis, transplant and graft loss were evaluated. Study endpoints included complete thrombotic microangiopathy (TMA) response, TMA event-free status, haematologic and renal parameters and adverse events. Of 100 patients, 74 had native kidneys and 26 in the transplant subgroup had a collective history of 38 grafts. No patients lost grafts and only one with pre-existing ESRD received a transplant on treatment. Efficacy endpoints were achieved similarly in both subgroups. After 26 weeks, mean absolute estimated glomerular filtration rate increased from baseline to 61 and 37 ml/min/1.73 m2 in native (n = 71; P < 0.0001) and transplanted kidney (n = 25; P = 0.0092) subgroups. Two patients (one/subgroup) developed meningococcal infections; both recovered, one continued therapy. Eculizumab was well tolerated. Eculizumab improved haematologic and renal outcomes in both subgroups. In patients with histories of multiple graft losses, eculizumab protected kidney function.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Síndrome Hemolítico-Urêmica Atípica/tratamento farmacológico , Falência Renal Crônica/cirurgia , Adulto , Idoso , Síndrome Hemolítico-Urêmica Atípica/mortalidade , Síndrome Hemolítico-Urêmica Atípica/cirurgia , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Rejeição de Enxerto , Sobrevivência de Enxerto , Humanos , Infusões Intravenosas , Análise de Intenção de Tratamento , Estimativa de Kaplan-Meier , Falência Renal Crônica/diagnóstico , Testes de Função Renal , Transplante de Rim/métodos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Medição de Risco , Análise de Sobrevida , Resultado do Tratamento
8.
J Digit Imaging ; 30(4): 477-486, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28695342

RESUMO

With many thyroid nodules being incidentally detected, it is important to identify as many malignant nodules as possible while excluding those that are highly likely to be benign from fine needle aspiration (FNA) biopsies or surgeries. This paper presents a computer-aided diagnosis (CAD) system for classifying thyroid nodules in ultrasound images. We use deep learning approach to extract features from thyroid ultrasound images. Ultrasound images are pre-processed to calibrate their scale and remove the artifacts. A pre-trained GoogLeNet model is then fine-tuned using the pre-processed image samples which leads to superior feature extraction. The extracted features of the thyroid ultrasound images are sent to a Cost-sensitive Random Forest classifier to classify the images into "malignant" and "benign" cases. The experimental results show the proposed fine-tuned GoogLeNet model achieves excellent classification performance, attaining 98.29% classification accuracy, 99.10% sensitivity and 93.90% specificity for the images in an open access database (Pedraza et al. 16), while 96.34% classification accuracy, 86% sensitivity and 99% specificity for the images in our local health region database.


Assuntos
Diagnóstico por Computador/métodos , Redes Neurais de Computação , Nódulo da Glândula Tireoide/classificação , Nódulo da Glândula Tireoide/diagnóstico por imagem , Biópsia por Agulha Fina , Humanos , Sensibilidade e Especificidade , Glândula Tireoide/diagnóstico por imagem , Glândula Tireoide/patologia , Nódulo da Glândula Tireoide/patologia , Ultrassonografia/métodos
9.
Nanoscale ; 9(29): 10350-10357, 2017 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-28702558

RESUMO

High mobility, scalable and even transparent thin-film transistors (TFTs) are always being pursued in the field of large area electronics. While excimer laser-beam-scanning can crystallize amorphous Si (a-Si) into high mobility poly-Si, it is limited to small areas. We here demonstrate a robust nano-droplet-scanning strategy that converts an a-Si:H thin film directly into periodic poly-Si nano-channels, with the aid of well-coordinated indium droplets. This enables the robust batch-fabrication of high performance Fin-TFTs with a high hole mobility of >100 cm2 V-1 s-1 and an excellent subthreshold swing of only 163 mV dec-1, via a low temperature <350 °C thin film process. More importantly, precise integration of tiny poly-Si channels, measuring only 60 nm in diameter and 2 µm apart on glass substrates, provides an unprecedented transparent Si-based TFT technology to visible light, which is widely sought for the next generation of high aperture displays and fully transparent electronics. The successful implementation of such a reliable nano-droplet-scanning strategy, rooted in the strength of nanoscale growth dynamics, will enable eventually the batch-manufacturing and upgrade of high performance large area electronics in general, and high definition and scalable flat-panel displays in particular.

10.
J Nephrol ; 30(1): 127-134, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26995002

RESUMO

BACKGROUND: Eculizumab is approved for atypical hemolytic uremic syndrome (aHUS). Guidelines discuss the importance of prompt treatment. We report a post hoc analysis investigating the effect of baseline factors, including patient characteristics and time from the latest aHUS manifestation to eculizumab initiation, on change from baseline in estimated glomerular filtration rate (eGFR) and other outcomes. METHODS: Data were pooled from four phase 2, open-label, single-arm, prospective clinical studies of eculizumab for patients with aHUS. Multivariate regressions identified predictors of eGFR change from baseline. The proportion of patients achieving sustained eGFR increase (defined: ≥15 ml/min/1.73 m2 for ≥28 days) and platelet count normalization were evaluated 1 year post-treatment. Baseline characteristics and eGFR outcomes were summarized by time to treatment from last aHUS manifestation [≤7 days (n = 21) versus >7 days (n = 76)]. RESULTS: Baseline eGFR were similar between groups. Multivariate regression analysis demonstrated time from aHUS manifestation to eculizumab treatment, age, baseline lactate dehydrogenase (LDH) and baseline hemoglobin were independently predictive of eGFR change from baseline. Mean eGFR change from baseline at 1 year was significantly higher in patients treated in ≤7 days than >7 days (57 vs. 23 ml/min/1.73 m2, p = 0.0098). After 1 year, 17/21 and 36/76 patients in the ≤7 and >7 day groups, respectively, achieved a sustained increase in eGFR. Mean time to platelet count normalization was similar between groups. CONCLUSIONS: Younger age, higher baseline LDH and lower baseline hemoglobin were associated with greater eGFR improvements. Early eculizumab initiation led to improved renal recovery, demonstrating the importance of rapid diagnosis and treatment of patients with aHUS.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Síndrome Hemolítico-Urêmica Atípica/tratamento farmacológico , Taxa de Filtração Glomerular , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Síndrome Hemolítico-Urêmica Atípica/fisiopatologia , Criança , Pré-Escolar , Feminino , Hemoglobinas/análise , Humanos , Lactente , Recém-Nascido , L-Lactato Desidrogenase/sangue , Masculino , Pessoa de Meia-Idade , Análise de Regressão
11.
Nano Lett ; 16(12): 7317-7324, 2016 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-27960468

RESUMO

The heteroepitaxial growth of crystal silicon thin films on sapphire, usually referred to as SoS, has been a key technology for high-speed mixed-signal integrated circuits and processors. Here, we report a novel nanoscale SoS heteroepitaxial growth that resembles the in-plane writing of self-aligned silicon nanowires (SiNWs) on R-plane sapphire. During a low-temperature growth at <350 °C, compared to that required for conventional SoS fabrication at >900 °C, the bottom heterointerface cultivates crystalline Si pyramid seeds within the catalyst droplet, while the vertical SiNW/catalyst interface subsequently threads the seeds into continuous nanowires, producing self-oriented in-plane SiNWs that follow a set of crystallographic directions of the sapphire substrate. Despite the low-temperature fabrication process, the field effect transistors built on the SoS-SiNWs demonstrate a high on/off ratio of >5 × 104 and a peak hole mobility of >50 cm2/V·s. These results indicate the novel potential of deploying in-plane SoS nanowire channels in places that require high-performance nanoelectronics and optoelectronics with a drastically reduced thermal budget and a simplified manufacturing procedure.

12.
Nat Commun ; 7: 12836, 2016 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-27682161

RESUMO

The ability to program highly modulated morphology upon silicon nanowires (SiNWs) has been fundamental to explore new phononic and electronic functionalities. We here exploit a nanoscale locomotion of metal droplets to demonstrate a large and readily controllable morphology engineering of crystalline SiNWs, from straight ones into continuous or discrete island-chains, at temperature <350 °C. This has been accomplished via a tin (Sn) droplet mediated in-plane growth where amorphous Si thin film is consumed as precursor to produce crystalline SiNWs. Thanks to a significant interface-stretching effect, a periodic Plateau-Rayleigh instability oscillation can be stimulated in the liquid Sn droplet, and the temporal oscillation of the Sn droplets is translated faithfully, via the deformable liquid/solid deposition interface, into regular spatial modulation upon the SiNWs. Combined with a unique self-alignment and positioning capability, this new strategy could enable a rational design and single-run fabrication of a wide variety of nanowire-based optoelectronic devices.

13.
Plant Physiol ; 164(1): 424-39, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24198318

RESUMO

MAX2 (for MORE AXILLARY GROWTH2) has been shown to regulate diverse biological processes, including plant architecture, photomorphogenesis, senescence, and karrikin signaling. Although karrikin is a smoke-derived abiotic signal, a role for MAX2 in abiotic stress response pathways is least investigated. Here, we show that the max2 mutant is strongly hypersensitive to drought stress compared with wild-type Arabidopsis (Arabidopsis thaliana). Stomatal closure of max2 was less sensitive to abscisic acid (ABA) than that of the wild type. Cuticle thickness of max2 was significantly thinner than that of the wild type. Both of these phenotypes of max2 mutant plants correlate with the increased water loss and drought-sensitive phenotype. Quantitative real-time reverse transcription-polymerase chain reaction analyses showed that the expression of stress-responsive genes and ABA biosynthesis, catabolism, transport, and signaling genes was impaired in max2 compared with wild-type seedlings in response to drought stress. Double mutant analysis of max2 with the ABA-insensitive mutants abi3 and abi5 indicated that MAX2 may function upstream of these genes. The expression of ABA-regulated genes was enhanced in imbibed max2 seeds. In addition, max2 mutant seedlings were hypersensitive to ABA and osmotic stress, including NaCl, mannitol, and glucose. Interestingly, ABA, osmotic stress, and drought-sensitive phenotypes were restricted to max2, and the strigolactone biosynthetic pathway mutants max1, max3, and max4 did not display any defects in these responses. Taken together, these results uncover an important role for MAX2 in plant responses to abiotic stress conditions.


Assuntos
Ácido Abscísico/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/fisiologia , Proteínas de Transporte/metabolismo , Ácido Abscísico/genética , Ácido Abscísico/farmacologia , Proteínas de Arabidopsis/genética , Proteínas de Transporte/genética , Secas , Proteínas F-Box/genética , Proteínas F-Box/metabolismo , Regulação da Expressão Gênica de Plantas , Germinação , Mutação , Estômatos de Plantas/efeitos dos fármacos , Plantas Geneticamente Modificadas , Plântula/genética , Plântula/crescimento & desenvolvimento , Transdução de Sinais/genética , Estresse Fisiológico
14.
J Comput Assist Tomogr ; 37(4): 499-504, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23863523

RESUMO

OBJECTIVE: The objective of this study was to correlate changes in computed tomography perfusion (CTP) parameters in the oropharyngeal mucosa following start of radiotherapy (RT) with acute mucositis in head and neck cancer patients. METHODS: Fifteen patients were prospectively evaluated with serial CTP imaging. Computed tomography perfusion studies were obtained before RT; at weeks 2, 4, and 6 during RT; and 6 weeks after completion of RT. RESULTS: At week 2 during RT, mean transition time increased to 13.9% and 261.8% in patients with and without mucositis, respectively (P = 0.024). At week 6 of RT, patients with grade 3 mucositis had a 325.4% increase in blood flow compared with a 58.3% increase in patients with grade 0-2 mucositis (P = 0.039). Mean transition time decreased by 29.9% and increased by 187.4% in patients with grade 3 and grade 0-2 mucositis, respectively (P = 0.025). CONCLUSIONS: Mean transition time and blood flow changes in the oropharyngeal mucosa correlated with the incidence and severity of RT-related mucositis.


Assuntos
Carcinoma de Células Escamosas/radioterapia , Neoplasias Orofaríngeas/radioterapia , Lesões por Radiação/diagnóstico por imagem , Lesões por Radiação/etiologia , Radioterapia Conformacional/efeitos adversos , Estomatite/diagnóstico por imagem , Estomatite/etiologia , Idoso , Carcinoma de Células Escamosas/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Orofaríngeas/complicações , Neoplasias Orofaríngeas/diagnóstico por imagem , Imagem de Perfusão/métodos , Prognóstico , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Estatística como Assunto , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento
15.
Neurosci Lett ; 544: 15-9, 2013 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-23562515

RESUMO

A recent in vivo study suggested that the delivery of adipose stromal cells (ASCs) protected rat brains from 6-hydroxydopamine (6-OHDA)-induced neurotoxicity. However, the molecular mechanism that underlies this neuroprotection remains unknown. It was suggested that ASCs-induced neuroprotection possibly resulting from released factors from ASCs. In this study, we investigated whether and how cell-free conditioned media collected from ASCs (ASC-CM) protect neurons against neurotoxicity induced by 6-OHDA in cultured rat rostral mesencephalic neurons (RMN) and cerebellar granule neurons (CGN). We now report that ASC-CM protects both RMN and CGN against 6-OHDA neurotoxicity. Exposure of CGN to 6-OHDA resulted in a significant increases in neuronal ROS and cell death. As expected, pretreatments with ASC-CM dramatically block both 6-OHDA-induced ROS and neurotoxicity. Additionally, ASC-CM also directly attenuated H2O2-induced neuronal death. Our results suggest that ASC-CM could block 6-OHDA-induced neuronal death by inhibiting both 6-OHDA-induced ROS generation and ROS-induced neurotoxicity in neurons. Both antioxidative and neuroprotective effects of ASC-CM may be beneficial in the therapy for Parkinson's disease and other neurodegenerative diseases.


Assuntos
Adipócitos/fisiologia , Comunicação Celular/fisiologia , Neurônios/patologia , Neurônios/fisiologia , Oxidopamina/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Células Estromais/fisiologia , Adipócitos/citologia , Animais , Comunicação Celular/efeitos dos fármacos , Células Cultivadas , Humanos , Neurônios/efeitos dos fármacos , Ratos , Células Estromais/citologia
16.
AJR Am J Roentgenol ; 199(5): 1105-13, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23096186

RESUMO

OBJECTIVE: This article describes the role of imaging in evaluating cervical lymphadenopathy in patients from birth to their mid-20s, illustrates imaging features of normal and abnormal lymph nodes, and highlights nodal imaging features and head and neck findings that assist in diagnosis. CONCLUSION: Cervical lymph node abnormalities are commonly encountered clinically and on imaging in children and young adults. Although imaging findings can lack specificity, nodal characteristics and associated head and neck imaging findings can assist in determining the underlying cause.


Assuntos
Diagnóstico por Imagem , Doenças Linfáticas/diagnóstico , Pescoço , Adolescente , Adulto , Criança , Pré-Escolar , Meios de Contraste , Diagnóstico Diferencial , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Lactente , Recém-Nascido , Doenças Linfáticas/patologia , Masculino
17.
Stroke ; 43(11): 3091-4, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22961963

RESUMO

BACKGROUND AND PURPOSE: Cerebral microbleeds (CMB) attributable to cerebral amyloid angiopathy generally occur in lobar regions, whereas those attributable to hypertensive vasculopathy are deep. Inflammation may be an underlying mechanism for CMB, with varying associations according to CMB location. Lipoprotein phospholipase-A2 (Lp-PLA2) is a circulating enzyme marker of vascular inflammation associated with risk of ischemic stroke and dementia. We hypothesized that higher Lp-PLA2 levels would be related to higher prevalence of CMB, with possible regional specificity. METHODS: Framingham Offspring participants aged 65 years or older with available Lp-PLA2 measures and brain magnetic resonance imaging were included. Logistic regression models were used to relate Lp-PLA2 activity and mass to presence of CMB, adjusted for age, sex, medication use (aspirin, anticoagulants, and statins), systolic blood pressure, APOE, current smoking, and diabetes. RESULTS: Eight-hundred nineteen participants (mean age, 73 years; 53% women) were included; 106 (13%) had CMB, 82 (10%) were lobar, and 27 (3%) were deep. We did not observe significant associations of CMB and LpPLA2 measures in multivariable adjusted analyses. However, there was a significant interaction between APOE genotype and Lp-PLA2 activity in their relation to presence of deep CMB (P interaction=0.01). Among persons with APOE ε3/ε3, the odds ratio for deep CMB was 0.95 (confidence interval, 0.59-1.53; P=0.83), whereas among those with at least 1 ε2 or ε4 allele, odds ratio was 3.46 (confidence interval, 1.43-8.36; P=0.006). CONCLUSIONS: In our community-based sample of older adults, there was no significant association of Lp-PLA2 with total or lobar CMB. The association of higher levels of Lp-PLA2 activity with deep CMB among those with at least 1 APOE ε2 or ε4 allele merits replication.


Assuntos
Hemorragia Cerebral/enzimologia , Fosfolipases A2/sangue , Idoso , Apolipoproteína E2/genética , Apolipoproteína E4/genética , Hemorragia Cerebral/sangue , Hemorragia Cerebral/genética , Feminino , Genótipo , Humanos , Imageamento por Ressonância Magnética , Masculino
18.
Int J Radiat Oncol Biol Phys ; 82(2): e119-27, 2012 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-21669502

RESUMO

PURPOSE: To measure changes in perfusion of the pharyngeal constrictor muscles (PCM) using CT perfusion (CTP) imaging during a course of definitive radiotherapy (RT) in head-and-neck cancer (HNC) patients and correlate with dysphagia outcome after RT. METHODS AND MATERIALS: Fifteen HNC patients underwent CTP imaging of the PCM at baseline and Weeks 2, 4, and 6 during RT and 6 weeks after RT. Blood flow and blood volume were measured in the PCM, and percentage change from baseline scan was determined. A single physician-based assessment of dysphagia was performed every 3 months after RT using the Common Terminology Criteria for Adverse Events, version 3.0 grading system. RESULTS: With a median follow-up of 28 months (range, 6-44 months), Grade 3 dysphagia was present in 7 of 15 patients, and 8 patients experienced Grade 0-2 dysphagia. The CTP parameters at Week 2 of RT demonstrated an increase in mean PCM blood flow of 161.9% vs. 12.3% (p = 0.007) and an increase in mean PCM blood volume of 96.6% vs. 8.7% (p = 0.039) in patients with 6-month post-RT Grade 3 dysphagia and Grade 0-2 dysphagia, respectively. On multivariate analysis, when adjusting for smoking history, tumor volume, and baseline dysphagia status, an increase in blood flow in the second week of RT was significant for 3- and 6-month Grade 3 dysphagia (p < 0.05). CONCLUSIONS: Perfusion changes in the PCM during Week 2 of RT in the PCM may predict the severity of dysphagia after HNC RT.


Assuntos
Transtornos de Deglutição/etiologia , Neoplasias de Cabeça e Pescoço/radioterapia , Músculos Faríngeos/efeitos da radiação , Idoso , Volume Sanguíneo/fisiologia , Volume Sanguíneo/efeitos da radiação , Quimiorradioterapia , Transtornos de Deglutição/diagnóstico por imagem , Transtornos de Deglutição/fisiopatologia , Feminino , Seguimentos , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada Multidetectores , Análise Multivariada , Músculos Faríngeos/irrigação sanguínea , Músculos Faríngeos/diagnóstico por imagem , Estudos Prospectivos , Radioterapia de Intensidade Modulada , Fluxo Sanguíneo Regional/fisiologia , Fluxo Sanguíneo Regional/efeitos da radiação , Fumar , Fatores de Tempo , Carga Tumoral
19.
J Sci Food Agric ; 91(2): 218-25, 2011 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-20848677

RESUMO

BACKGROUND: Safflower, whose botanic name is Carthamus tinctorius L., is a member of the family Compositae or Asteraceae. Carthamus yellow (CY) is the main constituent of safflower and is composed of safflomin A and safflomin B. Dried safflower petals are used in folk medicine and have been shown to invigorate blood circulation, break up blood stasis, and promote menstruation. In addition, dried safflower petals contain yellow dyes that are used to color food and cosmetics. In this study, we investigated the effects of dried safflower petals aqueous extracts (SFA) and CY on lipopolysaccharide (LPS)-induced inflammation using RAW264.7 macrophages. RESULTS: Our data showed that treatment with SFA (1-1000 microg mL(-1)) and CY (1-2000 microg mL(-1)) does not cause cytotoxicity in cells. SFA and CY inhibited LPS-stimulated nitric oxide (NO), prostaglandin E(2) (PGE(2)), and interleukin 1ß (IL-1ß) release, through attenuation of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) protein expression. Further, SFA and CY suppressed the LPS-induced phosphorylation of nuclear factor-κB, which was associated with the inhibition of IκB-α degradation. CONCLUSION: These results suggest that SFA and CY provide an anti-inflammatory response through inhibiting the production of NO and PGE(2) by the downregulation of iNOS and COX-2 gene expression. Thus safflower petals have the potential to provide a therapeutic approach to inflammation-associated disorders.


Assuntos
Carthamus tinctorius/química , Mediadores da Inflamação/metabolismo , Inflamação/tratamento farmacológico , Macrófagos/efeitos dos fármacos , Fenóis/uso terapêutico , Fitoterapia , Extratos Vegetais/uso terapêutico , Animais , Ciclo-Oxigenase 2/metabolismo , Flores/química , Proteínas I-kappa B/metabolismo , Inflamação/metabolismo , Lipopolissacarídeos , Camundongos , NF-kappa B/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Fenóis/isolamento & purificação , Fenóis/farmacologia , Fosforilação , Extratos Vegetais/farmacologia
20.
Radiographics ; 30(4): 1095-103, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20631370

RESUMO

With the increasing use of intensity-modulated radiation therapy (IMRT) for the treatment of head and neck cancer, radiation oncologists are expected to have an in-depth knowledge of the computed tomographic (CT) and magnetic resonance (MR) imaging anatomy of this region to be able to accurately characterize tumor extent and define organs at risk for potential radiation injury. The brachial plexus is a complex anatomic structure in the head and neck adjacent to diseased nodes and elective nodal volumes (ie, nodal areas that are prophylactically treated because they are at high risk for micrometastatic disease) and should, therefore, be carefully identified and contoured at CT prior to IMRT planning. A number of multi-institutional protocols mandate contouring the brachial plexus as an "avoidance structure" (ie, a structure or volume that is at risk for complications of radiation therapy) in the planning of head and neck radiation therapy, and, although little information exists on the best method of doing so consistently, contouring may be facilitated with fusion CT-MR imaging software. With three-dimensional conformal radiation therapy, the brachial plexus is not routinely contoured; therefore, its dose limits are not evaluated in treatment planning. In contrast, with IMRT, tolerance doses can be set to limit the maximum dose to the brachial plexus to 60 Gy in most radiation protocols, although the true radiation tolerance dose in patients with head and neck cancer has been mentioned only sporadically in the literature. Additional studies will be required to determine if identification of the brachial plexus as an avoidance structure prior to radiation therapy planning improves treatment outcome in patients with head and neck cancer and reduces long-term toxicity in this structure.


Assuntos
Plexo Braquial/diagnóstico por imagem , Plexo Braquial/patologia , Neoplasias de Cabeça e Pescoço/diagnóstico , Neoplasias de Cabeça e Pescoço/radioterapia , Imageamento por Ressonância Magnética/métodos , Radioterapia Conformacional/métodos , Tomografia Computadorizada por Raios X/métodos , Plexo Braquial/efeitos da radiação , Humanos , Prognóstico , Proteção Radiológica/métodos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos
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