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1.
Nat Commun ; 15(1): 5095, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38876987

RESUMO

Two-photon voltage imaging has long been heralded as a transformative approach capable of answering many long-standing questions in modern neuroscience. However, exploiting its full potential requires the development of novel imaging approaches well suited to the photophysical properties of genetically encoded voltage indicators. We demonstrate that parallel excitation approaches developed for scanless two-photon photostimulation enable high-SNR two-photon voltage imaging. We use whole-cell patch-clamp electrophysiology to perform a thorough characterization of scanless two-photon voltage imaging using three parallel illumination approaches and lasers with different repetition rates and wavelengths. We demonstrate voltage recordings of high-frequency spike trains and sub-threshold depolarizations from neurons expressing the soma-targeted genetically encoded voltage indicator JEDI-2P-Kv. Using a low repetition-rate laser, we perform multi-cell recordings from up to fifteen targets simultaneously. We co-express JEDI-2P-Kv and the channelrhodopsin ChroME-ST and capitalize on their overlapping two-photon absorption spectra to simultaneously evoke and image action potentials using a single laser source. We also demonstrate in vivo scanless two-photon imaging of multiple cells simultaneously up to 250 µm deep in the barrel cortex of head-fixed, anaesthetised mice.


Assuntos
Potenciais de Ação , Neurônios , Fótons , Animais , Camundongos , Neurônios/fisiologia , Potenciais de Ação/fisiologia , Técnicas de Patch-Clamp , Lasers
2.
Midwifery ; 135: 104026, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38781793

RESUMO

OBJECTIVE: Assess the outcome of induction of labour (IOL) with a Foley catheter in pregnancies at 41 weeks in midwifery-led care setting compared to consultant-led care setting. DESIGN: Mixed-methods cohort study at a midwifery - hospital partnership in Amsterdam, the Netherlands. SETTING AND PARTICIPANTS: Prospectively, women undergoing IOL in midwifery-led care were recruited at a secondary hospital. This group was compared to a retrospective cohort, in which IOL was exclusively performed under consultant-led care. MEASUREMENTS AND FINDINGS: We compared 320 women whose induction started in midwifery-led care to a historical cohort of 320 women induced for the same reason under consultant-led care. Both groups exhibited similar rates of spontaneous vaginal births (64.2 %vs62.5 %). Caesarean section and assisted vaginal birth rates did not significantly differ. Maternal adverse outcomes were comparable, while neonatal adverse outcomes were significantly higher in the midwifery-led care group (8.1 %vs3.8 %; OR 2.27, 95 % CI 1.12-4.58). The use of pain relief was significantly lower in midwife-led care (65.3 %vs75.3 %; OR 0.62, 95 % CI 0.44-0.87). 20.6 % of births occurred in midwife-led care. KEY CONCLUSIONS AND IMPLICATIONS FOR PRACTICE: In this single-centre study, spontaneous vaginal birth rates following IOL with a Foley catheter were similar between midwife- and consultant-led care. However, the midwife-led group showed a higher risk of adverse neonatal outcomes, mainly early onset neonatal sepsis, with a minority eventually delivering under midwife-led care. Implications highlight the need for broader research, validation across diverse settings and exploration of patient and healthcare worker perspectives to refine the evolving midwifery-led care model.


Assuntos
Trabalho de Parto Induzido , Tocologia , Humanos , Feminino , Trabalho de Parto Induzido/estatística & dados numéricos , Trabalho de Parto Induzido/métodos , Gravidez , Países Baixos , Adulto , Tocologia/métodos , Tocologia/estatística & dados numéricos , Estudos Retrospectivos , Estudos de Coortes , Estudos Prospectivos , Resultado da Gravidez/epidemiologia , Cateterismo Urinário/estatística & dados numéricos , Cateterismo Urinário/métodos , Cateterismo Urinário/efeitos adversos , Cateterismo Urinário/instrumentação
4.
Nat Commun ; 14(1): 1888, 2023 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-37019891

RESUMO

Two-photon, single-cell resolution optogenetics based on holographic light-targeting approaches enables the generation of precise spatiotemporal neuronal activity patterns and thus a broad range of experimental applications, such as high throughput connectivity mapping and probing neural codes for perception. Yet, current holographic approaches limit the resolution for tuning the relative spiking time of distinct cells to a few milliseconds, and the achievable number of targets to 100-200, depending on the working depth. To overcome these limitations and expand the capabilities of single-cell optogenetics, we introduce an ultra-fast sequential light targeting (FLiT) optical configuration based on the rapid switching of a temporally focused beam between holograms at kHz rates. We used FLiT to demonstrate two illumination protocols, termed hybrid- and cyclic-illumination, and achieve sub-millisecond control of sequential neuronal activation and high throughput multicell illumination in vitro (mouse organotypic and acute brain slices) and in vivo (zebrafish larvae and mice), while minimizing light-induced thermal rise. These approaches will be important for experiments that require rapid and precise cell stimulation with defined spatio-temporal activity patterns and optical control of large neuronal ensembles.


Assuntos
Holografia , Peixe-Zebra , Camundongos , Animais , Neurônios/fisiologia , Estimulação Luminosa/métodos , Holografia/métodos , Fótons , Optogenética/métodos , Luz
5.
Sci Adv ; 8(49): eadd7729, 2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36383037

RESUMO

The electric excitability of muscle, heart, and brain tissue relies on the precise interplay of Na+- and K+-selective ion channels. The involved ion fluxes are controlled in optogenetic studies using light-gated channelrhodopsins (ChRs). While non-selective cation-conducting ChRs are well established for excitation, K+-selective ChRs (KCRs) for efficient inhibition have only recently come into reach. Here, we report the molecular analysis of recently discovered KCRs from the stramenopile Hyphochytrium catenoides and identification of a novel type of hydrophobic K+ selectivity filter. Next, we demonstrate that the KCR signature motif is conserved in related stramenopile ChRs. Among them, WiChR from Wobblia lunata features a so far unmatched preference for K+ over Na+, stable photocurrents under continuous illumination, and a prolonged open-state lifetime. Showing high expression levels in cardiac myocytes and neurons, WiChR allows single- and two-photon inhibition at low irradiance and reduced tissue heating. Therefore, we recommend WiChR as the long-awaited efficient and versatile optogenetic inhibitor.


Assuntos
Luz , Potássio , Channelrhodopsins/genética , Channelrhodopsins/metabolismo , Potássio/metabolismo , Optogenética , Neurônios/fisiologia , Sódio/metabolismo
7.
ESMO Open ; 6(3): 100154, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34022731

RESUMO

BACKGROUND: Chemoradiotherapy (CRT) is the standard of care for patients diagnosed with locally advanced cervical cancer (LACC), a human papillomavirus (HPV)-related cancer that relapses in 30%-60% of patients. This study aimed to (i) design HPV droplet digital PCR (ddPCR) assays for blood detection (including rare genotypes) and (ii) monitor blood HPV circulating tumor DNA (HPV ctDNA) levels during CRT in patients with LACC. METHODS: We analyzed blood and tumor samples from 55 patients with HPV-positive LACC treated by CRT in a retrospective cohort (n = 41) and a prospective cohort (n = 14). HPV-ctDNA detection was carried out by genotype-specific ddPCR. RESULTS: HPV ctDNA was successfully detected in 69% of patients (n = 38/55) before CRT for LACC, including nine patients with a rare genotype. HPV-ctDNA level was correlated with HPV copy number in the tumor (r = 0.41, P < 0.001). HPV-ctDNA positivity for HPV18 (20%, n = 2/10) was significantly lower than for HPV16 (77%, n = 27/35) or other types (90%, n = 9/10, P = 0.002). HPV-ctDNA detection (positive versus negative) before CRT was associated with tumor stage (P = 0.037) and lymph node status (P = 0.02). Taking into account all samples from the end of CRT and during follow-up in the prospective cohort, positive HPV-ctDNA detection was associated with lower disease-free survival (DFS) (P = 0.048) and overall survival (OS) (P = 0.0013). CONCLUSION: This is one of the largest studies to report HPV-ctDNA detection before CRT and showed clearance of HPV ctDNA at the end of treatment in most patients. Residual HPV ctDNA at the end of CRT or during follow-up could help to identify patients more likely to experience subsequent relapse.


Assuntos
Alphapapillomavirus , DNA Tumoral Circulante , Infecções por Papillomavirus , Neoplasias do Colo do Útero , Quimiorradioterapia , DNA Tumoral Circulante/genética , Feminino , Humanos , Recidiva Local de Neoplasia , Papillomaviridae/genética , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/terapia , Estudos Prospectivos , Estudos Retrospectivos , Neoplasias do Colo do Útero/terapia
8.
Conserv Biol ; 35(5): 1463-1472, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33615559

RESUMO

Illegal, unregulated, and unreported (IUU) fishing poses a major threat to effective management of marine resources, affecting biodiversity and communities dependent on these coastal resources. Spatiotemporal patterns of industrial fisheries in developing countries are often poorly understood, and global efforts to describe spatial patterns of fishing vessel activity are currently based on automatic identification system (AIS) data. However, AIS is often not a legal requirement on fishing vessels, likely resulting in underestimates of the scale and distribution of legal and illegal fishing activity, which could have significant ramifications for targeted enforcement efforts and the management of fisheries resources. To help address this knowledge gap, we analyzed 3 years of vessel monitoring system (VMS) data in partnership with the national fisheries department in the Republic of the Congo to describe the behavior of national and distant-water industrial fleets operating in these waters. We found that the spatial footprint of the industrial fisheries fleet encompassed over one-quarter of the Exclusive Economic Zone. On average, 73% of fishing activity took place on the continental shelf (waters shallower than 200 m). Our findings highlight that VMS is not acting as a deterrent or being effectively used as a proactive management tool. As much as 33% (13% on average) of fishing effort occurred in prohibited areas set aside to protect biodiversity, including artisanal fisheries resources, and the distant-water fleet responsible for as much as 84% of this illegal activity. Given the growth in industrial and distant-water fleets across the region, as well as low levels of management and enforcement, these findings highlight that there is an urgent need for the global community to help strengthen regional and national capacity to analyze national scale data sets if efforts to combat IUU fishing are to be effective.


Amenazas de la Pesca Ilegal, No Regulada y No Reportada para la Biodiversidad y la Seguridad Alimentaria en la República del Congo Resumen La pesca ilegal, no regulada y no reportada (INN) representa una amenaza importante para el manejo efectivo de los recursos marinos, lo que afecta a la biodiversidad y a las comunidades que dependen de estos recursos costeros. Los patrones espaciotemporales de las pesquerías industriales en los países en desarrollo a menudo están poco comprendidas, y los esfuerzos globales para describir los patrones espaciales de la actividad de los navíos pesqueros actualmente están basados en los datos del sistema automático de identificación (SAI). Sin embargo, el SAI no es siempre un requerimiento legal en los navíos pesqueros, lo que probablemente resulta en valores subestimados de la escala y la distribución de la actividad pesquera legal e ilegal, lo que podría tener ramificaciones significativas para los esfuerzos enfocados de aplicación de la ley y para el manejo de los recursos de las pesquerías. Para ayudar a completar este vacío en el conocimiento, analizamos tres años de datos del sistema de monitoreo de navíos (SMN) en asociación con el departamento nacional de pesquerías de la República del Congo para describir el comportamiento de las flotas industriales nacionales y de altura que operan en estas aguas. Descubrimos que la huella espacial de la flota de pesquerías industriales abarcó más de un cuarto de la Zona Económica Exclusiva. En promedio, el 73% de la actividad pesquera se realizó en el talud continental (aguas con una profundidad menor a 200 m). Nuestros descubrimientos resaltan que el SMN no está actuando como un disuasivo o no se está usando efectivamente como una herramienta proactiva de manejo. Un máximo del 33% (13% en promedio) de los esfuerzos de pesca ocurrieron en áreas prohibidas apartadas para proteger a la biodiversidad, incluyendo los recursos para la pesca artesanal, con el 84% de la responsabilidad de esta actividad ilegal cayendo sobre las flotas de altura. Dado el crecimiento de flotas industriales y de altura en la región, así como los bajos niveles de manejo y aplicación de la ley, estos resultados resaltan la necesidad urgente que existe para que la comunidad global ayude a fortalecer la capacidad regional y nacional para analizar los conjuntos de datos de escala nacional si se espera que los esfuerzos para combatir la pesca INN sean efectivos.


Assuntos
Conservação dos Recursos Naturais , Segurança Alimentar , Biodiversidade , Congo , Pesqueiros
9.
Cancer Radiother ; 25(2): 175-181, 2021 Apr.
Artigo em Francês | MEDLINE | ID: mdl-33423966

RESUMO

Cholangiocarcinomas are digestive tumors whose incidence remains low and have poor prognosis. The benefits of adjuvant radiochemotherapy and radiotherapy have never been demonstrated in any phase III randomized controlled trial. Chemotherapy with capecitabine 6 months is the standard of care in adjuvant setting. Radiochemotherapy is validated in R1 patients. It is not recommended in neoadjuvant situations given the lack of evidence. Chemotherapy and radiochemotherapy are validated in adjuvant or locally advanced diseases. Stereotactic radiation therapy offers an interesting perspective, at the cost of significant digestive toxicities, requiring evaluation in randomized trials.


Assuntos
Neoplasias dos Ductos Biliares/radioterapia , Colangiocarcinoma/radioterapia , Antimetabólitos Antineoplásicos/uso terapêutico , Neoplasias dos Ductos Biliares/terapia , Capecitabina/uso terapêutico , Quimiorradioterapia Adjuvante , Quimioterapia Adjuvante , Colangiocarcinoma/terapia , Humanos , Prognóstico , Radiocirurgia , Radioterapia Adjuvante
10.
Cancer Radiother ; 24(4): 345-353, 2020 Jul.
Artigo em Francês | MEDLINE | ID: mdl-32360094

RESUMO

Preoperative radiotherapy boosted by chemotherapy is a recommended treatment in locally advanced rectal cancers. This treatment is delivered by three dimensional conformal irradiation, which is usually well tolerated but can induce potential toxicity such as rectitis, cystitis and hematologic adverse effects. Intensity-modulated radiotherapy, widely available nowadays, allows optimization of volume covering and sparing of organs at risk such as bladder and bone marrow. This review presents relevant clinical situations and requirements for a beneficial and safe preoperative irradiation of rectal cancers by intensity-modulated technique. This technique is compared to three-dimensional conformal radiotherapy.


Assuntos
Quimiorradioterapia/métodos , Radioterapia de Intensidade Modulada/métodos , Neoplasias Retais/terapia , Humanos , Órgãos em Risco/efeitos da radiação , Cuidados Pré-Operatórios/métodos , Lesões por Radiação/prevenção & controle , Radioterapia Conformacional/efeitos adversos , Radioterapia Guiada por Imagem/métodos , Neoplasias Retais/cirurgia
11.
Cancer Radiother ; 23(5): 385-394, 2019 Sep.
Artigo em Francês | MEDLINE | ID: mdl-31300328

RESUMO

PURPOSE: The purpose of the study was to evaluate the outcomes of stereotactic radiation therapy for primary and secondary liver tumours in Jean-Perrin cancer centre (Clermont-Ferrand, France) in terms of efficacy and safety. MATERIALS AND METHODS: Between December 2013 and June 2016, 25 patients were included. Treatment was performed on a linear accelerator Novalis TX®. The prescription dose was 42 to 60Gy in three to five fractions. Local control at 1 year was evaluated with modified Response Evaluation Criteria in Solid Tumours (mRECIST) and RECIST criteria. Acute and late toxicity were evaluated with Common Terminology Criteria for Adverse Events (CTCAE) v4.0 criteria. RESULTS: Median follow-up was 10.5 months. Treatment tolerance was good with few side effects grade 3 or above, no acute toxicity and only one late toxicity. We have highlighted that hepatic artery haemorrhage was associated with the presence of a biliary prosthesis in contact with the artery (P=0.006) and in the irradiation field. There was no correlation with the dose delivered to the artery and hepatic artery haemorrhage. CONCLUSION: Stereotactic radiation therapy for liver tumours allows a good local control with few secondary effects. Caution should be exercised when treating patients with biliary prostheses in the vicinity of the target volume because there is a risk of haemorrhage of the hepatic artery in contact with the prosthesis.


Assuntos
Neoplasias Hepáticas/radioterapia , Hipofracionamento da Dose de Radiação , Lesões por Radiação/etiologia , Radiocirurgia/efeitos adversos , Radioterapia de Intensidade Modulada/métodos , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/uso terapêutico , Carcinoma/radioterapia , Carcinoma/secundário , Carcinoma/terapia , Carcinoma Hepatocelular/radioterapia , Carcinoma Hepatocelular/terapia , Colangiocarcinoma/radioterapia , Colangiocarcinoma/terapia , Terapia Combinada , Intervalo Livre de Doença , Embolização Terapêutica , Feminino , Seguimentos , França/epidemiologia , Hemorragia/etiologia , Hepatectomia , Artéria Hepática/efeitos da radiação , Humanos , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/terapia , Masculino , Pessoa de Meia-Idade , Polietileno/efeitos da radiação , Polímeros/efeitos da radiação , Lesões por Radiação/epidemiologia , Planejamento da Radioterapia Assistida por Computador , Estudos Retrospectivos , Stents
12.
Cell Rep ; 24(5): 1243-1253.e5, 2018 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-30067979

RESUMO

In recent decades, optogenetics has been transforming neuroscience research, enabling neuroscientists to drive and read neural circuits. The recent development in illumination approaches combined with two-photon (2P) excitation, either sequential or parallel, has opened the route for brain circuit manipulation with single-cell resolution and millisecond temporal precision. Yet, the high excitation power required for multi-target photostimulation, especially under 2P illumination, raises questions about the induced local heating inside samples. Here, we present and experimentally validate a theoretical model that makes it possible to simulate 3D light propagation and heat diffusion in optically scattering samples at high spatial and temporal resolution under the illumination configurations most commonly used to perform 2P optogenetics: single- and multi-spot holographic illumination and spiral laser scanning. By investigating the effects of photostimulation repetition rate, spot spacing, and illumination dependence of heat diffusion, we found conditions that make it possible to design a multi-target 2P optogenetics experiment with minimal sample heating.


Assuntos
Encéfalo/efeitos da radiação , Temperatura Alta/efeitos adversos , Optogenética/métodos , Fótons/efeitos adversos , Potenciais de Ação , Animais , Encéfalo/fisiologia , Feminino , Holografia/métodos , Masculino , Camundongos , Camundongos Endogâmicos C57BL
13.
Front Behav Neurosci ; 12: 150, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30079015

RESUMO

Incidence of post-traumatic stress disorder (PTSD) ranges from 3 to 30% in individuals exposed to traumatic events, with the highest prevalence in groups exposed to combat, torture, or rape. To date, only a few FDA approved drugs are available to treat PTSD, which only offer symptomatic relief and variable efficacy. There is, therefore, an urgent need to explore new concepts regarding the biological responses causing PTSD. Animal models are an appropriate platform for conducting such studies. Herein, we examined the chronic behavioral and neurobiological effects of repeated unpredictable stress (RUS) in a mouse model. 12 weeks-old C57BL/6J male mice were exposed to a 21-day RUS paradigm consisting of exposures to a predator odor (TMT) whilst under restraint, unstable social housing, inescapable footshocks and social isolation. Validity of the model was assessed by comprehensive examination of behavioral outcomes at an acute timepoint, 3 and 6 months post-RUS; and molecular profiling was also conducted on brain and plasma samples at the acute and 6 months timepoints. Stressed mice demonstrated recall of traumatic memories, passive stress coping behavior, acute anxiety, and weight gain deficits when compared to control mice. Immunoblotting of amygdala lysates showed a dysregulation in the p75NTR/ProBDNF, and glutamatergic signaling in stressed mice at the acute timepoint. At 6 months after RUS, stressed mice had lower plasma corticosterone, reduced hippocampal CA1 volume and reduced brain-derived neurotrophic factor levels. In addition, glucocorticoid regulatory protein FKBP5 was downregulated in the hypothalamus of stressed mice at the same timepoint, together implicating an impaired hypothalamus-pituitary-adrenal-axis. Our model demonstrates chronic behavioral and neurobiological outcomes consistent with those reported in human PTSD cases and thus presents a platform through which to understand the neurobiology of stress and explore new therapeutic interventions.

14.
Ann Clin Transl Neurol ; 5(1): 64-80, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29376093

RESUMO

Objective: Exposure to repetitive concussion, or mild traumatic brain injury (mTBI), has been linked with increased risk of long-term neurodegenerative changes, specifically chronic traumatic encephalopathy (CTE). To date, preclinical studies largely have focused on the immediate aftermath of mTBI, with no literature on the lifelong consequences of mTBI in these models. This study provides the first account of lifelong neurobehavioral and histological consequences of repetitive mTBI providing unique insight into the constellation of evolving and ongoing pathologies with late survival. Methods: Male C57BL/6J mice (aged 2-3 months) were exposed to either single or repetitive mild TBI or sham procedure. Thereafter, animals were monitored and assessed at 24 months post last injury for measures of motor coordination, learning deficits, cognitive function, and anxiety-like behavior prior to euthanasia and preparation of the brains for detailed neuropathological and protein biochemical studies. Results: At 24 months survival animals exposed to r-mTBI showed clear evidence of learning and working memory impairment with a lack of spatial memory and vestibule-motor vestibulomotor deficits compared to sham animals. Associated with these late behavioral deficits there was evidence of ongoing axonal degeneration and neuroinflammation in subcortical white matter tracts. Notably, these changes were also observed after a single mTBI, albeit to a lesser degree than repetitive mTBI. Interpretation: In this context, our current data demonstrate, for the first time, that rather than an acute, time limited event, mild TBI can precipitate a lifelong degenerative process. These data therefore suggest that successful treatment strategies should consider both the acute and chronic nature of mTBI.

15.
Pain Pract ; 18(5): 647-665, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-28944983

RESUMO

BACKGROUND: Opioids provide effective relief from moderate-to-severe pain and should be prescribed as part of a multifaceted approach to pain management when other treatments have failed. Fixed-dose oxycodone/naloxone prolonged-release tablets (OXN PR) were designed to address the opioid class effect of opioid-induced constipation (OIC) by combining the analgesic efficacy of oxycodone with the opioid receptor antagonist, naloxone, which has negligible systemic availability when administered orally. This formulation has abuse-deterrent properties, since systemic exposure to naloxone by parenteral administration would antagonize the euphoric effects of oxycodone. METHODS: A literature search was conducted to assess the evidence base for OXN PR to treat moderate-to-severe pain and its impact on bowel function, based on published clinical trials and observational studies. RESULTS: Extensive data demonstrate that OXN PR provides effective analgesia and clinically relevant improvements in bowel function in patients with OIC and moderate-to-severe cancer-related pain and noncancer pain types such as low back pain, neuropathic pain, and musculoskeletal pain. OXN PR has also been found to improve bowel function in patients with OIC refractory to multiple types of laxatives, and improve Parkinson's disease-related pain. No unanticipated safety concerns have been reported in elderly patients. CONCLUSIONS: Evidence from clinical trials and observational studies confirms that for selected patients OXN PR significantly improves moderate-to-severe chronic pain and provides relief from OIC. Treatment should be tailored to individual patients to establish the lowest effective dose. An absence of analgesic ceiling effect was seen across the clinically relevant dose range investigated (≤ 160/80 mg/day).


Assuntos
Analgésicos Opioides/administração & dosagem , Constipação Intestinal/prevenção & controle , Naloxona/administração & dosagem , Antagonistas de Entorpecentes/administração & dosagem , Oxicodona/administração & dosagem , Manejo da Dor/métodos , Constipação Intestinal/induzido quimicamente , Preparações de Ação Retardada/administração & dosagem , Combinação de Medicamentos , Feminino , Humanos , Masculino
16.
Opt Express ; 25(11): 12640-12652, 2017 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-28786619

RESUMO

Computer-generated holography enables efficient light pattern generation through phase-only wavefront modulation. While perfect patterning usually requires control over both phase and amplitude, iterative Fourier transform algorithms (IFTA) can achieve phase-only approximations which maximize light efficiency at the cost of uniformity. The phase being unconstrained in the output plane, it can vary abruptly in some regions leading to destructive interferences. Among such structures phase vortices are the most common. Here we demonstrate theoretically, numerically and experimentally, a novel approach for eliminating phase vortices by spatially filtering the phase input to the IFTA, combining it with phase-based complex amplitude control at the spatial light modulator (SLM) plane to generate smooth shapes. The experimental implementation is achieved performing complex amplitude modulation with a phase-only SLM. This proposed experimental scheme offers a continuous and centered field of excitation. Lastly, we characterize achievable trade-offs between pattern uniformity, diffraction efficiency, and axial confinement.

17.
Acta Obstet Gynecol Scand ; 96(7): 868-876, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28295156

RESUMO

INTRODUCTION: Worldwide induction and cesarean delivery rates have increased rapidly, with consequences for subsequent pregnancies. The majority of intrapartum cesarean deliveries are performed for failure to progress, typically in nulliparous women at term. Current uterine registration techniques fail to identify inefficient contractions leading to first-stage labor arrest. An alternative technique, uterine electromyography has been shown to identify inefficient contractions leading to first-stage arrest of labor in nulliparous women with spontaneous onset of labor at term. The objective of this study was to determine whether this finding can be reproduced in induction of labor. MATERIAL AND METHODS: Uterine activity was measured in 141 nulliparous women with singleton term pregnancies and a fetus in cephalic position during induced labor. Electrical activity of the myometrium during contractions was characterized by its power density spectrum. RESULTS: No significant differences were found in contraction characteristics between women with induced labor delivering vaginally with or without oxytocin and women with arrested labor with subsequent cesarean delivery. CONCLUSION: Uterine electromyography shows no correlation with progression of labor in induced labor, which is in contrast to spontaneous labor.


Assuntos
Primeira Fase do Trabalho de Parto/fisiologia , Trabalho de Parto Induzido , Complicações do Trabalho de Parto/diagnóstico , Diagnóstico Pré-Natal , Contração Uterina/fisiologia , Adulto , Eletromiografia , Feminino , Humanos , Pessoa de Meia-Idade , Países Baixos , Complicações do Trabalho de Parto/fisiopatologia , Paridade , Gravidez , Estudos Prospectivos , Adulto Jovem
18.
BJOG ; 124(7): 1089-1094, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28128517

RESUMO

OBJECTIVE: This study compares two methods of evaluating para-aortic node involvement in locally advanced cervical cancer (LACC) in order to define external radiotherapy treatment fields: laparoscopic surgical para-aortic lymphadenectomy or PET-CT imaging. POPULATION: We selected 187 patients with LACC who had been treated by chemoradiation therapy in two comprehensive cancer centres from January 2001 to December 2013. A total of 98 underwent para-aortic evaluation by PET-CT (Centre 1) and 89 received surgical laparoscopic excision (Centre 2). METHODS: All patients with LACC were retrospectively collected in each centre. OS and DFS were calculated using the Kaplan-Meier's method and survival curves were compared using log-rank test. MAIN OUTCOME MEASURES: Outcomes were the comparison of patients' disease-free (DFS) and overall survival (OS) between the two centres. RESULTS: Patients had a significantly better disease-free survival in cohort 1 than in cohort 2, at 2 years [80.9% (71.7-87.5) versus 57.1% (46.1-67.3)] and at 5 years [70.5% (58.8-79.9) versus 49.2% (38.2-60.4)] (P = 0.009). These results are confirmed by multivariate analysis model [hazard ratio (HR) 1.93; 95% CI 1.03-3.61; P = 0.04]. The overall survival was also better in cohort 1, both at 2 and 5 years [93.5% (86.5-97.0) versus 78.5% (68.5-86.0) and 85.1% (73.2-92.2) versus 63.8% (51.9-74.2), respectively; P = 0.006]. The multivariate analysis model found concordant results with an increased relative risk of death for patients treated in cohort 2 (HR 2.55; 95% CI 1.09-5.99; P = 0.01). CONCLUSION: In this retrospective cohort analysis, para-aortic surgical staging in LACC is more deleterious for patients than is radiological staging in terms of OS and DFS. TWEETABLE ABSTRACT: Para-aortic surgical staging in LACC is more deleterious for patients than clinical staging.


Assuntos
Laparoscopia/métodos , Excisão de Linfonodo/métodos , Linfonodos/patologia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Neoplasias do Colo do Útero/patologia , Adulto , Idoso , Quimiorradioterapia/métodos , Estudos de Coortes , Feminino , França , Humanos , Linfonodos/diagnóstico por imagem , Linfonodos/cirurgia , Metástase Linfática/diagnóstico por imagem , Metástase Linfática/patologia , Pessoa de Meia-Idade , Estadiamento de Neoplasias/métodos , Estudos Retrospectivos , Análise de Sobrevida , Neoplasias do Colo do Útero/mortalidade , Neoplasias do Colo do Útero/cirurgia
19.
Front Aging Neurosci ; 9: 416, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29311903

RESUMO

Traumatic brain injury (TBI) is a serious public health concern which strikes someone every 15 s on average in the US. Even mild TBI, which comprise as many as 75% of all TBI cases, carries long term consequences. The effects of age and sex on long term outcome from TBI is not fully understood, but due to the increased risk for neurodegenerative diseases after TBI it is important to understand how these factors influence the outcome from TBI. This study examined the neurobehavioral and neuropathological effects of age and sex on the outcome 15 days following repetitive mild traumatic brain injury (r-mTBI) in mice transgenic for human tau (hTau). These mice express the six human isoforms of tau but do not express endogenous murine tau and they develop tau pathology and memory impairment in an age-dependent manner. After 5 mild impacts, aged female mice showed motor impairments that were absent in aged male mice, as well as younger animals. Conversely, aged female sham mice outperformed all other groups of aged mice in a Barnes maze spatial memory test. Pathologically, increases in IBA-1 and GFAP staining typically seen in this model of r-mTBI showed the expected increases with both injury and age, but phosphorylated tau stained with CP13 in the hippocampus (reduced in female sham mice compared to males) and PHF1 in the cortex (reduced in female TBI mice compared to male TBI mice) showed the only histological signs of sex-dependent differences in these mice.

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