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1.
Magn Reson Med ; 92(4): 1456-1470, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38748853

RESUMO

PURPOSE: To develop a 3D, high-sensitivity CEST mapping technique based on the 3D stack-of-spirals (SOS) gradient echo readout, the proposed approach was compared with conventional acquisition techniques and evaluated for its efficacy in concurrently mapping of guanidino (Guan) and amide CEST in human brain at 3 T, leveraging the polynomial Lorentzian line-shape fitting (PLOF) method. METHODS: Saturation time and recovery delay were optimized to achieve maximum CEST time efficiency. The 3DSOS method was compared with segmented 3D EPI (3DEPI), turbo spin echo, and gradient- and spin-echo techniques. Image quality, temporal SNR (tSNR), and test-retest reliability were assessed. Maps of Guan and amide CEST derived from 3DSOS were demonstrated on a low-grade glioma patient. RESULTS: The optimized recovery delay/saturation time was determined to be 1.4/2 s for Guan and amide CEST. In addition to nearly doubling the slice number, the gradient echo techniques also outperformed spin echo sequences in tSNR: 3DEPI (193.8 ± 6.6), 3DSOS (173.9 ± 5.6), and GRASE (141.0 ± 2.7). 3DSOS, compared with 3DEPI, demonstrated comparable GuanCEST signal in gray matter (GM) (3DSOS: [2.14%-2.59%] vs. 3DEPI: [2.15%-2.61%]), and white matter (WM) (3DSOS: [1.49%-2.11%] vs. 3DEPI: [1.64%-2.09%]). 3DSOS also achieves significantly higher amideCEST in both GM (3DSOS: [2.29%-3.00%] vs. 3DEPI: [2.06%-2.92%]) and WM (3DSOS: [2.23%-2.66%] vs. 3DEPI: [1.95%-2.57%]). 3DSOS outperforms 3DEPI in terms of scan-rescan reliability (correlation coefficient: 3DSOS: 0.58-0.96 vs. 3DEPI: -0.02 to 0.75) and robustness to motion as well. CONCLUSION: The 3DSOS CEST technique shows promise for whole-cerebrum CEST imaging, offering uniform contrast and robustness against motion artifacts.


Assuntos
Amidas , Encéfalo , Imageamento Tridimensional , Imageamento por Ressonância Magnética , Humanos , Amidas/química , Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Reprodutibilidade dos Testes , Imagem Ecoplanar/métodos , Glioma/diagnóstico por imagem , Algoritmos , Razão Sinal-Ruído , Neoplasias Encefálicas/diagnóstico por imagem , Adulto , Processamento de Imagem Assistida por Computador/métodos , Masculino , Feminino , Guanidina/química
2.
Front Pain Res (Lausanne) ; 5: 1394017, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38770243

RESUMO

Introduction: Low back pain is the most common type of chronic pain. We examined pain-related behaviors across 18 weeks in rats that received injury to one or two lumbar intervertebral discs (IVD) to determine if multi-level disc injuries enhance/prolong pain. Methods: Twenty-three Sprague-Dawley adult female rats were used: 8 received disc puncture (DP) of one lumbar IVD (L5/6, DP-1); 8 received DP of two lumbar IVDs (L4/5 & L5/6, DP-2); 8 underwent sham surgery. Results: DP-2 rats showed local (low back) sensitivity to pressure at 6- and 12-weeks post-injury, and remote sensitivity to pressure (upper thighs) at 12- and 18-weeks and touch (hind paws) at 6, 12 and 18-weeks. DP-1 rats showed local and remote pressure sensitivity at 12-weeks only (and no tactile sensitivity), relative to Sham DP rats. Both DP groups showed reduced distance traveled during gait testing over multiple weeks, compared to pre-injury; only DP-2 rats showed reduced distance relative to Sham DP rats at 12-weeks. DP-2 rats displayed reduced positive interactions with a novel adult female rat at 3-weeks and hesitation and freezing during gait assays from 6-weeks onwards. At study end (18-weeks), radiological and histological analyses revealed reduced disc height and degeneration of punctured IVDs. Serum BDNF and TNFα levels were higher at 18-weeks in DP-2 rats, relative to Sham DP rats, and levels correlated positively with remote sensitivity in hind paws (tactile) and thighs (pressure). Discussion: Thus, multi-level disc injuries resulted in earlier, prolonged and greater discomfort locally and remotely, than single-level disc injury. BDNF and TNFα may have contributing roles.

3.
Epilepsia ; 64(5): 1236-1247, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36815252

RESUMO

OBJECTIVE: Evaluating patients with drug-resistant epilepsy often requires inducing seizures by tapering antiseizure medications (ASMs) in the epilepsy monitoring unit (EMU). The relationship between ASM taper strategy, seizure timing, and severity remains unclear. In this study, we developed and validated a pharmacokinetic model of total ASM load and tested its association with seizure occurrence and severity in the EMU. METHODS: We studied 80 patients who underwent intracranial electroencephalographic recording for epilepsy surgery planning. We developed a first order pharmacokinetic model of the ASMs administered in the EMU to generate a continuous metric of overall ASM load. We then related modeled ASM load to seizure likelihood and severity. We determined the association between the rate of ASM load reduction, the length of hospital stay, and the probability of having a severe seizure. Finally, we used modeled ASM load to predict oncoming seizures. RESULTS: Seizures occurred in the bottom 50th percentile of sampled ASM loads across the cohort (p < .0001, Wilcoxon signed-rank test), and seizures requiring rescue therapy occurred at lower ASM loads than seizures that did not require rescue therapy (logistic regression mixed effects model, odds ratio = .27, p = .01). Greater ASM decrease early in the EMU was not associated with an increased likelihood of having a severe seizure, nor with a shorter length of stay. SIGNIFICANCE: A pharmacokinetic model can accurately estimate ASM levels for patients in the EMU. Lower modeled ASM levels are associated with increased seizure likelihood and seizure severity. We show that ASM load, rather than ASM taper speed, is associated with severe seizures. ASM modeling has the potential to help optimize taper strategy to minimize severe seizures while maximizing diagnostic yield.


Assuntos
Epilepsia Resistente a Medicamentos , Convulsões , Humanos , Convulsões/tratamento farmacológico , Epilepsia Resistente a Medicamentos/tratamento farmacológico , Eletrocorticografia , Tempo de Internação , Modelos Logísticos
5.
Int Urogynecol J ; 31(4): 799-807, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31673796

RESUMO

INTRODUCTION AND HYPOTHESIS: We aim to examine the financial relationship between industry and female pelvic medicine and reconstructive surgeons (FPMRS) during the first four full calendar years since the implementation of the Sunshine Act. METHODS: All board-certified FPMRS specialists were identified using the American Board of Medical Specialties directory. Program directors (PDs) were identified using an Accreditation Council for Graduate Medical Education (ACGME) database. All identified physicians were categorized by gender, specialty, and American Urological Association (AUA) region. Payment data for each individual from 2014 to 2017 were accessed using the Centers for Medicare and Medicaid Services (CMS) Open Payments website. Statistical analyses were performed to elucidate payment trends. RESULTS: Of the 1,307 FPMRS physicians identified, 25.1% (n = 328) are urology-trained and 74.9% (n = 979) are obstetrics/gynecology (OB/GYN)-trained. Of all physicians analyzed, 6.8% had no reported payments over the 4-year period. 90.1%, 86.5%, 85.3%, and 84.4% received some sort of payment in 2014 to 2017 respectively. Median total payments for all physicians decreased yearly, whereas mean payments decreased from 2014 to 2015 before increasing in all subsequent years. Median general payments were higher for men versus women, urology-trained versus OB/GYN-trained, and PDs versus non-PDs in all years analyzed. The largest contributor to overall payments was the "others" compensation category, which includes gifts, royalties, honoraria, and non-continuing medical education speaking engagements. CONCLUSIONS: Since institution of the Sunshine Act, the percentage of physicians receiving payments has decreased each year. Additionally, there has been a decrease in median total payments and an increase in yearly research payments in all years analyzed.


Assuntos
Procedimentos Cirúrgicos em Ginecologia , Cirurgiões , Urologia , Idoso , Centers for Medicare and Medicaid Services, U.S. , Bases de Dados Factuais , Feminino , Procedimentos Cirúrgicos em Ginecologia/economia , Humanos , Masculino , Medicare , Estados Unidos
6.
Nat Chem Biol ; 16(1): 50-59, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31819276

RESUMO

The post-genomic era has seen many advances in our understanding of cancer pathways, yet resistance and tumor heterogeneity necessitate multiple approaches to target even monogenic tumors. Here, we combine phenotypic screening with chemical genetics to identify pre-messenger RNA endonuclease cleavage and polyadenylation specificity factor 3 (CPSF3) as the target of JTE-607, a small molecule with previously unknown target. We show that CPSF3 represents a synthetic lethal node in a subset of acute myeloid leukemia (AML) and Ewing's sarcoma cancer cell lines. Inhibition of CPSF3 by JTE-607 alters expression of known downstream effectors in AML and Ewing's sarcoma lines, upregulates apoptosis and causes tumor-selective stasis in mouse xenografts. Mechanistically, it prevents the release of newly synthesized pre-mRNAs, resulting in read-through transcription and the formation of DNA-RNA hybrid R-loop structures. This study implicates pre-mRNA processing, and specifically CPSF3, as a druggable target providing an avenue to therapeutic intervention in cancer.


Assuntos
Fator de Especificidade de Clivagem e Poliadenilação/metabolismo , Leucemia Mieloide Aguda/metabolismo , Precursores de RNA/metabolismo , Sarcoma de Ewing/metabolismo , Animais , Apoptose/efeitos dos fármacos , Sítios de Ligação , Hidrolases de Éster Carboxílico/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular , Fator de Especificidade de Clivagem e Poliadenilação/genética , Células HEK293 , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Masculino , Espectrometria de Massas , Camundongos , Camundongos Endogâmicos C57BL , Transplante de Neoplasias , Fenótipo , Fenilalanina/análogos & derivados , Fenilalanina/farmacologia , Piperazinas/farmacologia , Ligação Proteica , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/metabolismo , Sarcoma de Ewing/tratamento farmacológico
7.
Nat Chem Biol ; 15(2): 179-188, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30643281

RESUMO

The identification of activating mutations in NOTCH1 in 50% of T cell acute lymphoblastic leukemia has generated interest in elucidating how these mutations contribute to oncogenic transformation and in targeting the pathway. A phenotypic screen identified compounds that interfere with trafficking of Notch and induce apoptosis via an endoplasmic reticulum (ER) stress mechanism. Target identification approaches revealed a role for SLC39A7 (ZIP7), a zinc transport family member, in governing Notch trafficking and signaling. Generation and sequencing of a compound-resistant cell line identified a V430E mutation in ZIP7 that confers transferable resistance to the compound NVS-ZP7-4. NVS-ZP7-4 altered zinc in the ER, and an analog of the compound photoaffinity labeled ZIP7 in cells, suggesting a direct interaction between the compound and ZIP7. NVS-ZP7-4 is the first reported chemical tool to probe the impact of modulating ER zinc levels and investigate ZIP7 as a novel druggable node in the Notch pathway.


Assuntos
Proteínas de Transporte de Cátions/genética , Estresse do Retículo Endoplasmático/fisiologia , Receptor Notch1/genética , Animais , Apoptose , Proteínas de Transporte/metabolismo , Proteínas de Transporte de Cátions/metabolismo , Proteínas de Transporte de Cátions/fisiologia , Linhagem Celular , Transformação Celular Neoplásica , Retículo Endoplasmático/fisiologia , Humanos , Mutação , Transporte Proteico , Receptor Notch1/fisiologia , Transdução de Sinais , Zinco/metabolismo
8.
J Vasc Interv Neurol ; 9(2): 55-61, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27829971

RESUMO

OBJECTIVE: To report upon technique of concurrent placement of angioplasty balloon at the internal jugular vein and sigmoid venous sinus junction to facilitate stent delivery in two patients in whom stent delivery past the jugular bulb was not possible. CLINICAL PRESENTATION: A 21-year-old woman and a 41-year-old woman with worsening headaches, visual obscuration or diplopia were treated for pseudotumor cerebri associated with transverse venous stenosis. Both patients had undergone primary angioplasty, which resulted in improvement in clinical symptoms followed by the recurrence of symptoms with restenosis at the site of angioplasty. INTERVENTION: After multiple attempts at stent delivery through jugular venous bulb were unsuccessful, a second guide catheter was placed in the ipsilateral internal jugular vein through contralateral femoral venous approach. A 6 mm × 20 mm (left) or 5 × 15 mm (right) angioplasty balloon was placed across the internal jugular vein and sigmoid sinus junction and partially inflated until the inflation and relative straightening of the junction was observed. In both patients, the internal jugular vein and sigmoid sinus junction was successfully traversed by the stent delivery system in a parallel alignment to inflated balloon. Balloon mounted stent was deployed at the site of restenosis with near complete resolution of lumen narrowing delivery and improvement in clinical symptoms. CONCLUSION: We report a technique for realignment and diameter change with concurrent placement and partial inflation of angioplasty balloon at the jugular venous bulb to facilitate stent delivery into the sigmoid and transverse venous sinuses in circumstances where multiple attempts at stent delivery are unsuccessful.

9.
RNA Biol ; 7(3): 373-80, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20421741

RESUMO

MicroRNAs (miRNAs) guide Argonaute (AGO)-containing microribonucleoprotein (miRNP) complexes to target mRNAs.It has been assumed that miRNAs behave similarly to each other with regard to mRNA target recognition. The usual assumptions, which are based on prior studies, are that miRNAs target preferentially sequences in the 3'UTR of mRNAs,guided by the 5' "seed" portion of the miRNAs. Here we isolated AGO- and miRNA-containing miRNPs from human H4 tumor cells by co-immunoprecipitation (co-IP) with anti-AGO antibody. Cells were transfected with miR-107, miR-124,miR-128, miR-320, or a negative control miRNA. Co-IPed RNAs were subjected to downstream high-density Affymetrix Human Gene 1.0 ST microarray analyses using an assay we validated previously-a "RIP-Chip" experimental design. RIP-Chip data provided a list of mRNAs recruited into the AGO-miRNP in correlation to each miRNA. These experimentally identified miRNA targets were analyzed for complementary six nucleotide "seed" sequences within the transfected miRNAs. We found that miR-124 targets tended to have sequences in the 3'UTR that would be recognized by the 5' seed of miR-124, as described in previous studies. By contrast, miR-107 targets tended to have 'seed' sequences in the mRNA open reading frame, but not the 3' UTR. Further, mRNA targets of miR-128 and miR-320 are less enriched for 6-mer seed sequences in comparison to miR-107 and miR-124. In sum, our data support the importance of the 5' seed in determining binding characteristics for some miRNAs; however, the "binding rules" are complex, and individual miRNAs can have distinct sequence determinants that lead to mRNA targeting.


Assuntos
MicroRNAs/metabolismo , MicroRNAs/fisiologia , Interferência de RNA/fisiologia , RNA Mensageiro/metabolismo , Animais , Sequência de Bases/fisiologia , Sítios de Ligação/genética , Humanos , Imunoprecipitação/métodos , Camundongos , MicroRNAs/química , MicroRNAs/genética , Modelos Biológicos , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/química , RNA Mensageiro/genética , Transfecção
10.
J Am Med Dir Assoc ; 8(1): 21-30, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17210499

RESUMO

OBJECTIVE: To investigate the utility of a clinical laboratory ELISA format assay that measures neural thread protein (NTP) in urine in the assessment of patients presenting with cognitive symptoms. DESIGN: A prospective blinded multicentered study. SETTING: Eight US specialty clinics for the evaluation of cognitive or memory disorder or dementia, including memory disorder and dementia clinics, neurology clinics, and psychiatry clinics, in 8 states. PARTICIPANTS: Prospectively enrolled consecutive patients who were newly referred to a specialty clinic for assessment of cognitive or memory disorder symptoms or dementia to rule out or rule in Alzheimer's disease (AD). MEASUREMENTS: Participants provided a first morning urine sample for UNTP measurement for testing at a central core laboratory and subsequently went through specialized diagnostic evaluations in accordance with established clinical criteria. Urine NTP measurement was compared to the diagnostic categorization of the patients as probable or possible AD (according to National Institute of Neurological Communicative Disorders and Stroke and the Alzheimer Disease and Related Disorders Association [NINCDS-ADRDA] criteria), mild cognitive impairment (MCI) (according to Quality Standards Subcommittee of the American Academy of Neurology [AAN] criteria) or definite non-AD. Clinical diagnoses were made without reference to UNTP measurement; the testing laboratory was blinded to both patient identity and clinical diagnoses. RESULTS: A total of 168 enrolled and consented patients provided qualifying urine samples and completed specialized diagnostic workups. There were 91.4% of subjects with probable AD, 37.7% of subjects categorized as possible AD, and 48.6% of subjects with MCI who had an elevated NTP measurement (>22 microg/mL). There were 90.7% of subjects diagnosed as definite non-AD who had a normal NTP measurement (< or =22 microg/mL). CONCLUSION: Noninvasive UNTP test results are potentially helpful as part of the workup of dementia for the nonspecialist to help in the decision as to whether referral and/or more detailed investigation is advisable.


Assuntos
Doença de Alzheimer/diagnóstico , Doença de Alzheimer/urina , Ensaio de Imunoadsorção Enzimática/métodos , Proteínas do Tecido Nervoso/urina , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/epidemiologia , Doença de Alzheimer/imunologia , Estudos de Casos e Controles , Diagnóstico Diferencial , Método Duplo-Cego , Ensaio de Imunoadsorção Enzimática/normas , Feminino , Humanos , Funções Verossimilhança , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Análise Multivariada , Prevalência , Estudos Prospectivos , Encaminhamento e Consulta , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Distribuição por Sexo , Estados Unidos/epidemiologia
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