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1.
N Engl J Med ; 390(1): 55-62, 2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38169490

RESUMO

Antiamyloid antibodies have been used to reduce cerebral amyloid-beta (Aß) load in patients with Alzheimer's disease. We applied focused ultrasound with each of six monthly aducanumab infusions to temporarily open the blood-brain barrier with the goal of enhancing amyloid removal in selected brain regions in three participants over a period of 6 months. The reduction in the level of Aß was numerically greater in regions treated with focused ultrasound than in the homologous regions in the contralateral hemisphere that were not treated with focused ultrasound, as measured by fluorine-18 florbetaben positron-emission tomography. Cognitive tests and safety evaluations were conducted over a period of 30 to 180 days after treatment. (Funded by the Harry T. Mangurian, Jr. Foundation and the West Virginia University Rockefeller Neuroscience Institute.).


Assuntos
Doença de Alzheimer , Barreira Hematoencefálica , Terapia por Ultrassom , Humanos , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/análise , Barreira Hematoencefálica/metabolismo , Encéfalo/irrigação sanguínea , Encéfalo/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/métodos , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/uso terapêutico
2.
Proc Natl Acad Sci U S A ; 117(17): 9180-9182, 2020 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-32284421

RESUMO

The blood-brain barrier (BBB) presents a significant challenge for treating brain disorders. The hippocampus is a key target for novel therapeutics, playing an important role in Alzheimer's disease (AD), epilepsy, and depression. Preclinical studies have shown that magnetic resonance (MR)-guided low-intensity focused ultrasound (FUS) can reversibly open the BBB and facilitate delivery of targeted brain therapeutics. We report initial clinical trial results evaluating the safety, feasibility, and reversibility of BBB opening with FUS treatment of the hippocampus and entorhinal cortex (EC) in patients with early AD. Six subjects tolerated a total of 17 FUS treatments with no adverse events and neither cognitive nor neurological worsening. Post-FUS contrast MRI revealed immediate and sizable hippocampal parenchymal enhancement indicating BBB opening, followed by BBB closure within 24 h. The average opening was 95% of the targeted FUS volume, which corresponds to 29% of the overall hippocampus volume. We demonstrate that FUS can safely, noninvasively, transiently, reproducibly, and focally mediate BBB opening in the hippocampus/EC in humans. This provides a unique translational opportunity to investigate therapeutic delivery in AD and other conditions.


Assuntos
Barreira Hematoencefálica/diagnóstico por imagem , Barreira Hematoencefálica/metabolismo , Terapia por Ultrassom/métodos , Idoso , Doença de Alzheimer/metabolismo , Transporte Biológico , Barreira Hematoencefálica/fisiologia , Encéfalo/fisiologia , Sistemas de Liberação de Medicamentos/métodos , Feminino , Hipocampo/metabolismo , Humanos , Masculino , Microbolhas , Pessoa de Meia-Idade , Ondas Ultrassônicas , Ultrassonografia
3.
Ann Neurol ; 89(3): 426-443, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33252146

RESUMO

Deep brain stimulation (DBS) depends on precise delivery of electrical current to target tissues. However, the specific brain structures responsible for best outcome are still debated. We applied probabilistic stimulation mapping to a retrospective, multidisorder DBS dataset assembled over 15 years at our institution (ntotal = 482 patients; nParkinson disease = 303; ndystonia = 64; ntremor = 39; ntreatment-resistant depression/anorexia nervosa = 76) to identify the neuroanatomical substrates of optimal clinical response. Using high-resolution structural magnetic resonance imaging and activation volume modeling, probabilistic stimulation maps (PSMs) that delineated areas of above-mean and below-mean response for each patient cohort were generated and defined in terms of their relationships with surrounding anatomical structures. Our results show that overlap between PSMs and individual patients' activation volumes can serve as a guide to predict clinical outcomes, but that this is not the sole determinant of response. In the future, individualized models that incorporate advancements in mapping techniques with patient-specific clinical variables will likely contribute to the optimization of DBS target selection and improved outcomes for patients. ANN NEUROL 2021;89:426-443.


Assuntos
Anorexia Nervosa/terapia , Estimulação Encefálica Profunda/métodos , Transtorno Depressivo Resistente a Tratamento/terapia , Distonia/terapia , Doença de Parkinson/terapia , Tremor/terapia , Adulto , Idoso , Mapeamento Encefálico , Conectoma , Feminino , Globo Pálido/diagnóstico por imagem , Giro do Cíngulo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Modelagem Computacional Específica para o Paciente , Probabilidade , Estudos Retrospectivos , Núcleo Subtalâmico/diagnóstico por imagem , Resultado do Tratamento , Núcleos Ventrais do Tálamo/diagnóstico por imagem
4.
Breast Cancer Res ; 23(1): 78, 2021 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-34344445

RESUMO

BACKGROUND: The ovarian hormones estrogen and progesterone (EP) are implicated in breast cancer causation. A specific consequence of progesterone exposure is the expansion of the mammary stem cell (MSC) and luminal progenitor (LP) compartments. We hypothesized that this effect, and its molecular facilitators, could be abrogated by progesterone receptor (PR) antagonists administered in a mouse model. METHODS: Ovariectomized FVB mice were randomized to 14 days of treatment: sham, EP, EP + telapristone (EP + TPA), EP + mifepristone (EP + MFP). Mice were then sacrificed, mammary glands harvested, and mammary epithelial cell lineages separated by flow cytometry using cell surface markers. RNA from each lineage was sequenced and differential gene expression was analyzed using DESeq. Quantitative PCR was performed to confirm the candidate genes discovered in RNA seq. ANOVA with Tukey post hoc analysis was performed to compare relative expression. Alternative splicing events were examined using the rMATs multivariate analysis tool. RESULTS: Significant increases in the MSC and luminal mature (LM) cell fractions were observed following EP treatment compared to control (p < 0.01 and p < 0.05, respectively), whereas the LP fraction was significantly reduced (p < 0.05). These hormone-induced effects were reversed upon exposure to TPA and MFP (p < 0.01 for both). Gene Ontology analysis of RNA-sequencing data showed EP-induced enrichment of several pathways, with the largest effect on Wnt signaling in MSC, significantly repressed by PR inhibitors. In LP cells, significant induction of Wnt4 and Rankl, and Wnt pathway intermediates Lrp2 and Axin2 (confirmed by qRTPCR) were reversed by TPA and MFP (p < 0.0001). Downstream signaling intermediates of these pathways (Lrp5, Mmp7) showed similar effects. Expression of markers of epithelial-mesenchymal transition (Cdh1, Cdh3) and the induction of EMT regulators (Zeb1, Zeb2, Gli3, Snai1, and Ptch2) were significantly responsive to progesterone. EP treatment was associated with large-scale alternative splicing events, with an enrichment of motifs associated with Srsf, Esrp, and Rbfox families. Exon skipping was observed in Cdh1, Enah, and Brd4. CONCLUSIONS: PR inhibition reverses known tumorigenic pathways in the mammary gland and suppresses a previously unknown effect of progesterone on RNA splicing events. In total, our results strengthen the case for reconsideration of PR inhibitors for breast cancer prevention.


Assuntos
Glândulas Mamárias Animais/metabolismo , Progesterona/metabolismo , Receptores de Progesterona/antagonistas & inibidores , Células-Tronco/citologia , Processamento Alternativo/efeitos dos fármacos , Animais , Proliferação de Células/efeitos dos fármacos , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Transição Epitelial-Mesenquimal/genética , Estrogênios/metabolismo , Estrogênios/farmacologia , Feminino , Antagonistas de Hormônios/farmacologia , Glândulas Mamárias Animais/citologia , Glândulas Mamárias Animais/efeitos dos fármacos , Camundongos , Progesterona/farmacologia , Fatores de Processamento de RNA/genética , Proteínas de Ligação a RNA/genética , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Células-Tronco/efeitos dos fármacos , Células-Tronco/metabolismo
5.
Radiology ; 298(3): 654-662, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33399511

RESUMO

Background Opening of the blood-brain barrier (BBB) induced with MRI-guided focused ultrasound has been shown in experimental animal models to reduce amyloid-ß plaque burden, improve memory performance, and facilitate delivery of therapeutic agents to the brain. However, physiologic effects of this procedure in humans with Alzheimer disease (AD) require further investigation. Purpose To assess imaging effects of focused ultrasound-induced BBB opening in the hippocampus of human participants with early AD and to evaluate fluid flow patterns after BBB opening by using serial contrast-enhanced MRI. Materials and Methods Study participants with early AD recruited to a Health Insurance Portability and Accountability Act-compliant, prospective, ongoing phase II clinical trial (ClinicalTrials.gov identifier, NCT03671889) underwent three separate focused ultrasound-induced BBB opening procedures that used a 220-kHz transducer with a concomitant intravenous microbubble contrast agent administered at 2-week intervals targeting the hippocampus and entorhinal cortex between October 2018 and May 2019. Posttreatment effects and gadolinium-based contrast agent enhancement patterns were evaluated by using 3.0-T MRI. Results Three women (aged 61, 72, and 73 years) consecutively enrolled in the trial successfully completed repeated focused ultrasound-induced BBB opening of the hippocampus and entorhinal cortex. Postprocedure contrast enhancement was clearly identified within the targeted brain volumes, indicating immediate spatially precise BBB opening. Parenchymal enhancement resolved within 24 hours after all treatments, confirming BBB closure. Transient perivenous enhancement was consistently observed during the acute phase after BBB opening. Notably, contrast enhancement reappeared in the perivenular regions after BBB closure. This imaging marker is consistent with blood-meningeal barrier permeability and persisted for 24-48 hours before spontaneous resolution. No evidence of intracranial hemorrhage or other adverse effect was identified. Conclusion MRI-guided focused ultrasound-induced blood-brain barrier opening was safely performed in the hippocampi of three participants with Alzheimer disease without any adverse effects. Posttreatment MRI reveals a unique spatiotemporal contrast enhancement pattern that suggests a perivenular immunologic healing response downstream from targeted sites. © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by Klibanov in this issue.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/tratamento farmacológico , Barreira Hematoencefálica/diagnóstico por imagem , Sistemas de Liberação de Medicamentos/métodos , Imagem por Ressonância Magnética Intervencionista/métodos , Terapia por Ultrassom/métodos , Idoso , Meios de Contraste , Córtex Entorrinal , Feminino , Hipocampo , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos
6.
J Med Internet Res ; 23(1): e20123, 2021 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-33475518

RESUMO

BACKGROUND: The impending scale up of noncommunicable disease screening programs in low- and middle-income countries coupled with limited health resources require that such programs be as accurate as possible at identifying patients at high risk. OBJECTIVE: The aim of this study was to develop machine learning-based risk stratification algorithms for diabetes and hypertension that are tailored for the at-risk population served by community-based screening programs in low-resource settings. METHODS: We trained and tested our models by using data from 2278 patients collected by community health workers through door-to-door and camp-based screenings in the urban slums of Hyderabad, India between July 14, 2015 and April 21, 2018. We determined the best models for predicting short-term (2-month) risk of diabetes and hypertension (a model for diabetes and a model for hypertension) and compared these models to previously developed risk scores from the United States and the United Kingdom by using prediction accuracy as characterized by the area under the receiver operating characteristic curve (AUC) and the number of false negatives. RESULTS: We found that models based on random forest had the highest prediction accuracy for both diseases and were able to outperform the US and UK risk scores in terms of AUC by 35.5% for diabetes (improvement of 0.239 from 0.671 to 0.910) and 13.5% for hypertension (improvement of 0.094 from 0.698 to 0.792). For a fixed screening specificity of 0.9, the random forest model was able to reduce the expected number of false negatives by 620 patients per 1000 screenings for diabetes and 220 patients per 1000 screenings for hypertension. This improvement reduces the cost of incorrect risk stratification by US $1.99 (or 35%) per screening for diabetes and US $1.60 (or 21%) per screening for hypertension. CONCLUSIONS: In the next decade, health systems in many countries are planning to spend significant resources on noncommunicable disease screening programs and our study demonstrates that machine learning models can be leveraged by these programs to effectively utilize limited resources by improving risk stratification.


Assuntos
Diabetes Mellitus/diagnóstico , Hipertensão/diagnóstico , Aprendizado de Máquina/normas , Diabetes Mellitus/economia , Diagnóstico Precoce , Feminino , Humanos , Hipertensão/economia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Medição de Risco
7.
Radiology ; 296(2): 250-262, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32573388

RESUMO

MRI is a valuable clinical and research tool for patients undergoing deep brain stimulation (DBS). However, risks associated with imaging DBS devices have led to stringent regulations, limiting the clinical and research utility of MRI in these patients. The main risks in patients with DBS devices undergoing MRI are heating at the electrode tips, induced currents, implantable pulse generator dysfunction, and mechanical forces. Phantom model studies indicate that electrode tip heating remains the most serious risk for modern DBS devices. The absence of adverse events in patients imaged under DBS vendor guidelines for MRI demonstrates the general safety of MRI for patients with DBS devices. Moreover, recent work indicates that-given adequate safety data-patients may be imaged outside these guidelines. At present, investigators are primarily focused on improving DBS device and MRI safety through the development of tools, including safety simulation models. Existing guidelines provide a standardized framework for performing safe MRI in patients with DBS devices. It also highlights the possibility of expanding MRI as a tool for research and clinical care in these patients going forward.


Assuntos
Encéfalo/diagnóstico por imagem , Estimulação Encefálica Profunda/instrumentação , Imageamento por Ressonância Magnética , Segurança do Paciente/normas , Simulação por Computador , Temperatura Alta/efeitos adversos , Humanos , Imageamento por Ressonância Magnética/efeitos adversos , Imageamento por Ressonância Magnética/normas , Próteses Neurais/efeitos adversos , Imagens de Fantasmas
8.
Radiology ; 293(1): 174-183, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31385756

RESUMO

BackgroundWith growing numbers of patients receiving deep brain stimulation (DBS), radiologists are encountering these neuromodulation devices at an increasing rate. Current MRI safety guidelines, however, limit MRI access in these patients.PurposeTo describe an MRI (1.5 T and 3 T) experience and safety profile in a large cohort of participants with active DBS systems and characterize the hardware-related artifacts on images from functional MRI.Materials and MethodsIn this prospective study, study participants receiving active DBS underwent 1.5- or 3-T MRI (T1-weighted imaging and gradient-recalled echo [GRE]-echo-planar imaging [EPI]) between June 2017 and October 2018. Short- and long-term adverse events were tracked. The authors quantified DBS hardware-related artifacts on images from GRE-EPI (functional MRI) at the cranial coil wire and electrode contacts. Segmented artifacts were then transformed into standard space to define the brain areas affected by signal loss. Two-sample t tests were used to assess the difference in artifact size between 1.5- and 3-T MRI.ResultsA total of 102 participants (mean age ± standard deviation, 60 years ± 11; 65 men) were evaluated. No MRI-related short- and long-term adverse events or acute changes were observed. DBS artifacts were most prominent near the electrode contacts and over the frontoparietal cortical area where the redundancy of the extension wire is placed subcutaneously. The mean electrode contact artifact diameter was 9.3 mm ± 1.6, and 1.9% ± 0.8 of the brain was obscured by the coil artifact. The coil artifacts were larger at 3 T than at 1.5 T, obscuring 2.1% ± 0.7 and 1.4% ± 0.7 of intracranial volume, respectively (P < .001). The superficial frontoparietal cortex and deep structures neighboring the electrode contacts were most commonly obscured.ConclusionWith a priori local safety testing, patients receiving deep brain stimulation may safely undergo 1.5- and 3-T MRI. Deep brain stimulation hardware-related artifacts only affect a small proportion of the brain.© RSNA, 2019Online supplemental material is available for this article.See also the editorial by Martin in this issue.


Assuntos
Artefatos , Encéfalo/diagnóstico por imagem , Estimulação Encefálica Profunda/instrumentação , Eletrodos Implantados , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Imagem Ecoplanar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
9.
Plant Biotechnol J ; 17(8): 1567-1581, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30672092

RESUMO

Sclerotinia sclerotiorum, a predominately necrotrophic fungal pathogen with a broad host range, causes a significant yield-limiting disease of soybean called Sclerotinia stem rot. Resistance mechanisms against this pathogen in soybean are poorly understood, thus hindering the commercial deployment of resistant varieties. We used a multiomic approach utilizing RNA-sequencing, gas chromatography-mass spectrometry-based metabolomics and chemical genomics in yeast to decipher the molecular mechanisms governing resistance to S. sclerotiorum in soybean. Transcripts and metabolites of two soybean recombinant inbred lines, one resistant and one susceptible to S. sclerotiorum were analysed in a time course experiment. The combined results show that resistance to S. sclerotiorum in soybean is associated in part with an early accumulation of JA-Ile ((+)-7-iso-jasmonoyl-L-isoleucine), a bioactive jasmonate, increased ability to scavenge reactive oxygen species, and importantly, a reprogramming of the phenylpropanoid pathway leading to increased antifungal activities. Indeed, we noted that phenylpropanoid pathway intermediates, such as 4-hydroxybenzoate, cinnamic acid, ferulic acid and caffeic acid, were highly accumulated in the resistant line. In vitro assays show that these metabolites and total stem extracts from the resistant line clearly affect S. sclerotiorum growth and development. Using chemical genomics in yeast, we further show that this antifungal activity targets ergosterol biosynthesis in the fungus, by disrupting enzymes involved in lipid and sterol biosynthesis. Overall, our results are consistent with a model where resistance to S. sclerotiorum in soybean coincides with an early recognition of the pathogen, leading to the modulation of the redox capacity of the host and the production of antifungal metabolites.


Assuntos
Ascomicetos/patogenicidade , Resistência à Doença/genética , Ergosterol/biossíntese , Glycine max/genética , Glycine max/microbiologia , Doenças das Plantas/genética , Regulação da Expressão Gênica de Plantas , Doenças das Plantas/microbiologia , Regulação para Cima
10.
J Magn Reson Imaging ; 49(6): 1736-1749, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30552842

RESUMO

BACKGROUND: The majority of Parkinson's disease patients with deep brain stimulation (DBS) use a monopolar configuration, which presents challenges for EEG and MRI studies. The literature reports algorithms to convert monopolar to bipolar settings. PURPOSE/HYPOTHESIS: To assess brain responses of Parkinson's disease patients implanted with DBS during fMRI studies using their clinical and presumed equivalent settings using a published conversion recipe. STUDY TYPE: Prospective. SUBJECTS: Thirteen DBS patients. FIELD STRENGTH/SEQUENCE: 1.5T and 3T, fMRI using gradient echo-planar imaging. ASSESSMENT: Patients underwent 30/30sec ON/OFF DBS fMRI scans using monopolar and bipolar settings. To convert to a bipolar setting, the negative contact used for the monopolar configuration remained constant and the adjacent dorsal contact was rendered positive, while increasing the voltage by 30%. fMRI activation/deactivation maps and motor Unified Parkinson's Disease Rating Scale (UPDRS-III) scores were compared for patients in both configurations. STATISTICAL TESTS: T-tests were used to compare UPDRS scores and volumes of tissue activated (VTA) diameters in monopolar and bipolar configurations. RESULTS: The patterns of fMRI activation in the monopolar and bipolar configurations were generally different. The thalamus, pallidum, and visual cortices exhibited higher activation using the patient's clinical settings than the presumed equivalent settings. VTA diameters were lower (7 mm vs. 6.3 mm, P = 0.047) and UPDRS scores were generally higher in the bipolar (33.2 ± 16) than in the monopolar configuration (28.3 ± 17.4), without reaching statistical significance (P > 0.05). DATA CONCLUSION: Monopolar and bipolar configurations result in different patterns of brain activation while using a previously published monopolar-bipolar conversion algorithm. Clinical benefits may be achieved with varying patterns of brain responses. Blind conversion from one to the other should be avoided for purposes of understanding the mechanisms of DBS. LEVEL OF EVIDENCE: 1 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2018.


Assuntos
Encéfalo/diagnóstico por imagem , Estimulação Encefálica Profunda/instrumentação , Imagem Ecoplanar , Imageamento por Ressonância Magnética , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/terapia , Idoso , Algoritmos , Desenho de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Segurança do Paciente , Estudos Prospectivos
11.
Brain ; 141(12): 3405-3414, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30452554

RESUMO

Magnetic resonance guided focused ultrasound (MRgFUS) thalamotomy is a novel and minimally invasive ablative treatment for essential tremor. The size and location of therapeutic lesions producing the optimal clinical benefits while minimizing adverse effects are not known. We examined these relationships in patients with essential tremor undergoing MRgFUS. We studied 66 patients with essential tremor who underwent MRgFUS between 2012 and 2017. We assessed the Clinical Rating Scale for Tremor (CRST) scores at 3 months after the procedure and tracked the adverse effects (sensory, motor, speech, gait, and dysmetria) 1 day (acute) and 3 months after the procedure. Clinical data associated with the postoperative Day 1 lesions were used to correlate the size and location of lesions with tremor benefit and acute adverse effects. Diffusion-weighted imaging was used to assess whether acute adverse effects were related to lesions encroaching on nearby major white matter tracts (medial lemniscus, pyramidal, and dentato-rubro-thalamic). The area of optimal tremor response at 3 months after the procedure was identified at the posterior portion of the ventral intermediate nucleus. Lesions extending beyond the posterior region of the ventral intermediate nucleus and lateral to the lateral thalamic border were associated with increased risk of acute adverse sensory and motor effects, respectively. Acute adverse effects on gait and dysmetria occurred with lesions inferolateral to the thalamus. Lesions inferolateral to the thalamus or medial to the ventral intermediate nucleus were also associated with acute adverse speech effects. Diffusion-weighted imaging revealed that lesions associated with adverse sensory and gait/dysmetria effects compromised the medial lemniscus and dentato-rubro-thalamic tracts, respectively. Lesions associated with adverse motor and speech effects encroached on the pyramidal tract. Lesions larger than 170 mm3 were associated with an increased risk of acute adverse effects. Tremor improvement and acute adverse effects of MRgFUS for essential tremor are highly dependent on the location and size of lesions. These novel findings could refine current MRgFUS treatment planning and targeting, thereby improving clinical outcomes in patients.


Assuntos
Tremor Essencial/terapia , Tálamo/patologia , Terapia por Ultrassom , Idoso , Imagem de Tensor de Difusão , Tremor Essencial/diagnóstico , Tremor Essencial/patologia , Feminino , Humanos , Imagem por Ressonância Magnética Intervencionista , Masculino , Sensibilidade e Especificidade , Resultado do Tratamento , Substância Branca/patologia
12.
Epilepsia ; 59(12): 2284-2295, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30374947

RESUMO

OBJECTIVE: The purpose of this study is to investigate the outcomes of epilepsy surgery targeting the subcentimeter-sized resting state functional magnetic resonance imaging (rs-fMRI) epileptogenic onset zone (EZ) in hypothalamic hamartoma (HH). METHODS: Fifty-one children with HH-related intractable epilepsy received anatomical MRI-guided stereotactic laser ablation (SLA) procedures. Fifteen of these children were control subjects (CS) not guided by rs-fMRI. Thirty-six had been preoperatively guided by rs-fMRI (RS) to determine EZs, which were subsequently targeted by SLA. The primary outcome measure for the study was a predetermined goal of 30% reduction in seizure frequency and improvement in class I Engel outcomes 1 year postoperatively. Quantitative and qualitative volumetric analyses of total HH and ablated tissue were also assessed. RESULTS: In the RS group, the EZ target within the HH was ablated with high accuracy (>87.5% of target ablated in 83% of subjects). There was no difference between the groups in percentage of ablated hamartoma volume (P = 0.137). Overall seizure reduction was higher in the rs-fMRI group: 85% RS versus 49% CS (P = 0.0006, adjusted). The Engel Epilepsy Surgery Outcome Scale demonstrated significant differences in those with freedom from disabling seizures (class I), 92% RS versus 47% CS, a 45% improvement (P = 0.001). Compared to prior studies, there was improvement in class I outcomes (92% vs 76%-81%). No postoperative morbidity or mortality occurred. SIGNIFICANCE: For the first time, surgical SLA targeting of subcentimeter-sized EZs, located by rs-fMRI, guided surgery for intractable epilepsy. Our outcomes demonstrated the highest seizure freedom rate without surgical complications and are a significant improvement over prior reports. The approach improved freedom from seizures by 45% compared to conventional ablation, regardless of hamartoma size or anatomical classification. This technique showed the same or reduced morbidity (0%) compared to recent non-rs-fMRI-guided SLA studies with as high as 20% permanent significant morbidity.


Assuntos
Epilepsia Resistente a Medicamentos/diagnóstico por imagem , Epilepsia Resistente a Medicamentos/cirurgia , Hamartoma/cirurgia , Doenças Hipotalâmicas/cirurgia , Neoplasias Hipotalâmicas/cirurgia , Procedimentos Neurocirúrgicos/métodos , Adolescente , Criança , Pré-Escolar , Epilepsia Resistente a Medicamentos/etiologia , Feminino , Hamartoma/complicações , Hamartoma/diagnóstico por imagem , Humanos , Doenças Hipotalâmicas/complicações , Doenças Hipotalâmicas/diagnóstico por imagem , Neoplasias Hipotalâmicas/complicações , Neoplasias Hipotalâmicas/diagnóstico por imagem , Lactente , Imageamento por Ressonância Magnética , Masculino , Complicações Pós-Operatórias/epidemiologia , Reprodutibilidade dos Testes , Resultado do Tratamento , Adulto Jovem
13.
Stereotact Funct Neurosurg ; 96(2): 120-126, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29847826

RESUMO

BACKGROUND: The visualization of the subthalamic nucleus (STN) on magnetic resonance imaging (MRI) is variable. Studies of the contribution of patient-related factors and intrinsic brain volumetrics to STN visualization have not been reported previously. OBJECTIVE: To assess the visualization of the STN during deep brain stimulation (DBS) surgery in a clinical setting. METHODS: Eighty-two patients undergoing pre-operative MRI to plan for STN DBS for Parkinson disease were retrospectively studied. The visualization of the STN and its borders was assessed and scored by 3 independent observers using a 4-point ordinal scale (from 0 = not seen to 3 = excellent visualization). This measure was then correlated with the patients' clinical information and brain volumes. RESULTS: The mean STN visualization scores were 1.68 and 1.63 for the right and left STN, respectively, with a good interobserver reliability (intraclass correlation coefficient: 0.744). Older age and decreased white matter volume were negatively correlated with STN visualization (p < 0.05). CONCLUSION: STN visualization is only fair to good on routine MRI with good concordance of interindividual rating. Advancing age and decreased white matter are associated with poor visualization of the STN. Knowledge about factors contributing to poor visualization of the STN could alert a surgeon to modify the imaging strategy to optimize surgical targeting.


Assuntos
Imageamento por Ressonância Magnética/métodos , Doença de Parkinson/diagnóstico por imagem , Cuidados Pré-Operatórios/métodos , Núcleo Subtalâmico/diagnóstico por imagem , Idoso , Estimulação Encefálica Profunda/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/cirurgia , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Estudos Retrospectivos , Núcleo Subtalâmico/cirurgia , Resultado do Tratamento
14.
Int J Cancer ; 140(11): 2484-2497, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28263391

RESUMO

Risk biomarkers for estrogen receptor (ER)-negative breast cancer have clear value for breast cancer prevention. We previously reported a set of lipid metabolism (LiMe) genes with high expression in the contralateral unaffected breasts (CUBs) of ER-negative cancer cases. We now further examine LiMe gene expression in both tumor and CUB, and investigate the role of Pre-B-cell leukemia homeobox-1 (PBX1) as a candidate common transcription factor for LiMe gene expression. mRNA was extracted from laser-capture microdissected epithelium from tumor and CUB of 84 subjects (28 ER-positive cases, 28 ER-negative cases, 28 healthy controls). Gene expression was quantitated by qRT-PCR. Logistic regression models were generated to predict ER status of the contralateral cancer. Protein expression of HMGCS2 and PBX1 was measured using immunohistochemistry. The effect of PBX1 on LiMe gene expression was examined by overexpressing PBX1 in MCF10A cells with or without ER, and by suppressing PBX1 in MDA-MB-453 cells. The expression of DHRS2, HMGCS2, UGT2B7, UGT2B11, ALOX15B, HPGD, UGT2B28 and GLYATL1 was significantly higher in ER-negative versus ER-positive CUBs, and predicted ER status of the tumor in test and validation sets. In contrast, LiMe gene expression was significantly lower in ER-negative than ER-positive tumors. PBX1 overexpression in MCF10A cells up-regulated most LiMe genes, but not in MCF10A cells overexpressing ER. Suppressing PBX1 in MDA-MB-453 cells resulted in decrease of LiMe gene expression. Four binding sites of PBX1 and cofactor were identified in three lipid metabolism genes using ChIP-qPCR. These data suggest a novel role for PBX1 in the regulation of lipid metabolism genes in benign breast, which may contribute to ER-negative tumorigenesis.


Assuntos
Neoplasias da Mama/genética , Proteínas de Ligação a DNA/genética , Metabolismo dos Lipídeos/genética , Proteínas Proto-Oncogênicas/genética , Receptores de Estrogênio/genética , Adulto , Idoso , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Pessoa de Meia-Idade , Fator de Transcrição 1 de Leucemia de Células Pré-B , RNA Mensageiro/genética , Regulação para Cima/genética
15.
BJU Int ; 119(2): 342-348, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27431021

RESUMO

OBJECTIVE: To investigate tyrosine kinase inhibitors (TKI) and gold nanorods (AuNRs) paired with photothermal ablation in a human metastatic clear cell renal cell carcinoma (RCC) mouse model. Nanoparticles have been successful as a platform for targeted drug delivery in the treatment of urological cancers. Likewise, the use of nanoparticles in photothermal tumour ablation, although early in its development, has provided promising results. Our previous in vitro studies of nanoparticles loaded with both TKI and AuNRs and activated with photothermal ablation have shown significant synergistic cell kill greater than each individual arm alone. This study is a translation of our initial findings to an in vivo model. MATERIALS AND METHODS: Immunologically naïve nude mice (athymic nude-Foxn1nu ) were injected subcutaneously bilaterally in both flanks (n = 36) with 2.5 × 106 cells of a human metastatic renal cell carcinoma cell line (RCC 786-O). Subcutaneous xenograft tumours developed into 1-cm palpable nodules. AuNRs encapsulated in human serum albumin protein (HSA) nanoparticles were synthesised with or without a TKI and injected directly into the tumour nodule. Irradiation was administered with an 808-nm light-emitting diode laser for 6 min. Mice were humanely killed 14 days after irradiation; tumours were excised, formalin fixed, paraffin embedded, and evaluated for size and the percentage of necrosis by a genitourinary pathologist. The untreated contralateral flank tumours were used as controls. RESULTS: In mice that did not receive irradiation, TKI alone yielded 4.2% tumour necrosis on the injected side and administration of HSA-AuNR-TKI alone yielded 11.1% necrosis. In the laser-ablation models, laser ablation alone yielded 62% necrosis and when paired with HSA-AuNR there was 63.4% necrosis. The combination of laser irradiation and HSA-AuNR-TKI had cell kill rate of 100%. CONCLUSIONS: In the absence of laser irradiation, TKI treatment alone or when delivered via nanoparticles produced moderate necrosis. Irradiation with and without gold particles alone also improves tumour necrosis. However, when irradiation is paired with gold particles and drug-loaded nanoparticles, the combined therapy showed the most significant and synergistic complete tumour necrosis of 100% (P < 0.05). This study illustrates the potential of combination nanotechnology as a new approach in the treatment of urological cancers.


Assuntos
Carcinoma de Células Renais/terapia , Ouro/administração & dosagem , Neoplasias Renais/terapia , Terapia a Laser , Nanotecnologia , Nanotubos , Proteínas Tirosina Quinases/administração & dosagem , Técnicas de Ablação , Animais , Terapia Combinada , Modelos Animais de Doenças , Masculino , Camundongos , Camundongos Nus , Resultado do Tratamento
16.
Microbiology (Reading) ; 162(8): 1286-1299, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27267959

RESUMO

Bacteriocins are antimicrobial peptides (AMPs) produced by bacteria to acquire survival benefits during competitive inter- and intra-species interactions in complex ecosystems. In this study, an AMP-producing soil bacterial strain designated SKDU10 was isolated and identified as a member of the genus Brevibacillus. The AMP produced by strain SKDU10 identified as a class IId bacteriocin with 57.6 % homology to laterosporulin, a defensin-like class IId bacteriocin. However, substantial differences were observed in the antimicrobial activity spectrum of this bacteriocin named laterosporulin10 when compared to laterosporulin. Laterosporulin10 effectively inhibited the growth of Staphylococcus aureus and Mycobacterium tuberculosis (Mtb H37Rv) with LD50 values of 4.0 µM and 0.5 µM, respectively. Furthermore, laterosporulin10 inhibited the growth of Mtb H37Rv strain at about 20 times lower MIC value compared to S. aureus MTCC 1430 or M. smegmatis MC2 155 in vitro and ex vivo. Electron micrographs along with membrane permeabilization studies using FACS analysis revealed that laterosporulin10 is a membrane-permeabilizing peptide. Interestingly, laterosporulin10 was able to efficiently kill Mtb H37Rv strain residing inside the macrophages and did not show haemolysis up to 40 µM concentration.


Assuntos
Antibacterianos/farmacologia , Bacteriocinas/farmacologia , Brevibacillus/metabolismo , Defensinas/farmacologia , Mycobacterium smegmatis/efeitos dos fármacos , Mycobacterium tuberculosis/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Sequência de Aminoácidos , Antibacterianos/metabolismo , Bacteriocinas/metabolismo , Sequência de Bases , DNA Bacteriano/genética , Defensinas/metabolismo , Genoma Bacteriano/genética , Testes de Sensibilidade Microbiana , Mycobacterium smegmatis/crescimento & desenvolvimento , Mycobacterium tuberculosis/crescimento & desenvolvimento , Análise de Sequência de DNA , Staphylococcus aureus/crescimento & desenvolvimento
17.
BMC Cancer ; 16: 326, 2016 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-27215412

RESUMO

BACKGROUND: The synthesis of specific, potent progesterone antagonists adds potential agents to the breast cancer prevention and treatment armamentarium. The identification of individuals who will benefit from these agents will be a critical factor for their clinical success. METHODS: We utilized telapristone acetate (TPA; CDB-4124) to understand the effects of progesterone receptor (PR) blockade on proliferation, apoptosis, promoter binding, cell cycle progression, and gene expression. We then identified a set of genes that overlap with human breast luteal-phase expressed genes and signify progesterone activity in both normal breast cells and breast cancer cell lines. RESULTS: TPA administration to T47D cells results in a 30 % decrease in cell number at 24 h, which is maintained over 72 h only in the presence of estradiol. Blockade of progesterone signaling by TPA for 24 h results in fewer cells in G2/M, attributable to decreased expression of genes that facilitate the G2/M transition. Gene expression data suggest that TPA affects several mechanisms that progesterone utilizes to control gene expression, including specific post-translational modifications, and nucleosomal organization and higher order chromatin structure, which regulate access of PR to its DNA binding sites. CONCLUSIONS: By comparing genes induced by the progestin R5020 in T47D cells with those increased in the luteal-phase normal breast, we have identified a set of genes that predict functional progesterone signaling in tissue. These data will facilitate an understanding of the ways in which drugs such as TPA may be utilized for the prevention, and possibly the therapy, of human breast cancer.


Assuntos
Neoplasias da Mama/metabolismo , Redes Reguladoras de Genes/efeitos dos fármacos , Norpregnadienos/farmacologia , Promegestona/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Feminino , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Células MCF-7 , Análise de Sequência com Séries de Oligonucleotídeos/métodos
18.
Br J Neurosurg ; 30(1): 91-6, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26158193

RESUMO

Spinal epidural abscess is a rare clinical entity with considerable morbidity. Even with prompt diagnosis and treatment, many patients are left with persistent residual neurological deficits. The present study details the outcome in 23 patients of primary pyogenic spinal epidural abscess, addressing the outcome following late presentation at a neurological facility. At presentation only 2 patients had relatively preserved neurological status. Eleven patients were paraplegic. All the patients underwent laminectomy and evacuation of abscess. A good functional outcome was observed in almost half of the patients, and there was a significant reduction in the number of the patients with severe disability. Factors influencing the outcome are described in this study.


Assuntos
Abscesso Epidural/cirurgia , Espaço Epidural/cirurgia , Adolescente , Adulto , Feminino , Humanos , Laminectomia/métodos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Compressão da Medula Espinal/cirurgia , Infecções Estafilocócicas/diagnóstico , Infecções Estafilocócicas/cirurgia , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
19.
Stem Cells ; 32(4): 983-97, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24715691

RESUMO

Emerging evidence suggests that mesenchymal stem cells (MSCs) are often recruited to tumor sites but their functional significance in tumor growth and disease progression remains elusive. Herein we report that prostate cancer (PC) cell microenvironment subverts PC patient adipose-derived stem cells (pASCs) to undergo neoplastic transformation. Unlike normal ASCs, the pASCs primed with PC cell conditioned media (CM) formed prostate-like neoplastic lesions in vivo and reproduced aggressive tumors in secondary recipients. The pASC tumors acquired cytogenetic aberrations and mesenchymal-to-epithelial transition and expressed epithelial, neoplastic, and vasculogenic markers reminiscent of molecular features of PC tumor xenografts. Our mechanistic studies revealed that PC cell-derived exosomes are sufficient to recapitulate formation of prostate tumorigenic mimicry generated by CM-primed pASCs in vivo. In addition to downregulation of the large tumor suppressor homolog2 and the programmed cell death protein 4, a neoplastic transformation inhibitor, the tumorigenic reprogramming of pASCs was associated with trafficking by PC cell-derived exosomes of oncogenic factors, including H-ras and K-ras transcripts, oncomiRNAs miR-125b, miR-130b, and miR-155 as well as the Ras superfamily of GTPases Rab1a, Rab1b, and Rab11a. Our findings implicate a new role for PC cell-derived exosomes in clonal expansion of tumors through neoplastic reprogramming of tumor tropic ASCs in cancer patients.


Assuntos
Tecido Adiposo/metabolismo , Comunicação Celular , Transformação Celular Neoplásica/metabolismo , Transição Epitelial-Mesenquimal , Exossomos/metabolismo , Neoplasias da Próstata/metabolismo , Células-Tronco/metabolismo , Tecido Adiposo/patologia , Transformação Celular Neoplásica/patologia , Exossomos/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias/metabolismo , Neoplasias da Próstata/patologia , RNA Neoplásico/metabolismo , Células-Tronco/patologia
20.
Stereotact Funct Neurosurg ; 93(2): 122-126, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25721340

RESUMO

Background: Stimulation parameters are crucial for the efficacy and safety of motor cortex stimulation (MCS). Motor threshold (MT) can be defined as the lowest voltage that produces motor contraction. The final stimulation parameters are always a smaller percentage of MT in order to avoid seizures. We determined how patient position and activity affect MT. Methods: Prospective MT measurements were made while patients were either lying down or sitting up, and in a resting state or while actively contracting the target muscle. Paired 1-tailed t tests were performed to assess for statistically significant differences between MT measurements made under the 4 different combinations of position and activity. Results: The MT was lower when the target muscle was being actively contracted compared to resting in both supine and upright positions (both p < 0.001). The MT was also lower when upright compared to supine in both resting and active states of muscle contraction (both p < 0.001). The mean difference between supine resting and upright active states is 0.79 V. Conclusion: When selecting final stimulation parameters for MCS, clinicians should be aware that the lowest MT is elicited while patients are seated upright and actively contracting the target muscle. Using this method of determining the MT when calculating the final stimulation parameters could reduce the chance of MCS-induced seizures. © 2015 S. Karger AG, Basel.

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