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1.
Nature ; 555(7695): 223-226, 2018 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-29516995

RESUMO

The depth to which Jupiter's observed east-west jet streams extend has been a long-standing question. Resolving this puzzle has been a primary goal for the Juno spacecraft, which has been in orbit around the gas giant since July 2016. Juno's gravitational measurements have revealed that Jupiter's gravitational field is north-south asymmetric, which is a signature of the planet's atmospheric and interior flows. Here we report that the measured odd gravitational harmonics J3, J5, J7 and J9 indicate that the observed jet streams, as they appear at the cloud level, extend down to depths of thousands of kilometres beneath the cloud level, probably to the region of magnetic dissipation at a depth of about 3,000 kilometres. By inverting the measured gravity values into a wind field, we calculate the most likely vertical profile of the deep atmospheric and interior flow, and the latitudinal dependence of its depth. Furthermore, the even gravity harmonics J8 and J10 resulting from this flow profile also match the measurements, when taking into account the contribution of the interior structure. These results indicate that the mass of the dynamical atmosphere is about one per cent of Jupiter's total mass.

2.
Nature ; 555(7695): 227-230, 2018 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-29517000

RESUMO

Jupiter's atmosphere is rotating differentially, with zones and belts rotating at speeds that differ by up to 100 metres per second. Whether this is also true of the gas giant's interior has been unknown, limiting our ability to probe the structure and composition of the planet. The discovery by the Juno spacecraft that Jupiter's gravity field is north-south asymmetric and the determination of its non-zero odd gravitational harmonics J3, J5, J7 and J9 demonstrates that the observed zonal cloud flow must persist to a depth of about 3,000 kilometres from the cloud tops. Here we report an analysis of Jupiter's even gravitational harmonics J4, J6, J8 and J10 as observed by Juno and compared to the predictions of interior models. We find that the deep interior of the planet rotates nearly as a rigid body, with differential rotation decreasing by at least an order of magnitude compared to the atmosphere. Moreover, we find that the atmospheric zonal flow extends to more than 2,000 kilometres and to less than 3,500 kilometres, making it fully consistent with the constraints obtained independently from the odd gravitational harmonics. This depth corresponds to the point at which the electric conductivity becomes large and magnetic drag should suppress differential rotation. Given that electric conductivity is dependent on planetary mass, we expect the outer, differentially rotating region to be at least three times deeper in Saturn and to be shallower in massive giant planets and brown dwarfs.

3.
Nature ; 555(7695): 220-222, 2018 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-29517001

RESUMO

The gravity harmonics of a fluid, rotating planet can be decomposed into static components arising from solid-body rotation and dynamic components arising from flows. In the absence of internal dynamics, the gravity field is axially and hemispherically symmetric and is dominated by even zonal gravity harmonics J2n that are approximately proportional to qn, where q is the ratio between centrifugal acceleration and gravity at the planet's equator. Any asymmetry in the gravity field is attributed to differential rotation and deep atmospheric flows. The odd harmonics, J3, J5, J7, J9 and higher, are a measure of the depth of the winds in the different zones of the atmosphere. Here we report measurements of Jupiter's gravity harmonics (both even and odd) through precise Doppler tracking of the Juno spacecraft in its polar orbit around Jupiter. We find a north-south asymmetry, which is a signature of atmospheric and interior flows. Analysis of the harmonics, described in two accompanying papers, provides the vertical profile of the winds and precise constraints for the depth of Jupiter's dynamical atmosphere.

4.
Nature ; 549(7670): 66-69, 2017 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-28880294

RESUMO

The most intense auroral emissions from Earth's polar regions, called discrete for their sharply defined spatial configurations, are generated by a process involving coherent acceleration of electrons by slowly evolving, powerful electric fields directed along the magnetic field lines that connect Earth's space environment to its polar regions. In contrast, Earth's less intense auroras are generally caused by wave scattering of magnetically trapped populations of hot electrons (in the case of diffuse aurora) or by the turbulent or stochastic downward acceleration of electrons along magnetic field lines by waves during transitory periods (in the case of broadband or Alfvénic aurora). Jupiter's relatively steady main aurora has a power density that is so much larger than Earth's that it has been taken for granted that it must be generated primarily by the discrete auroral process. However, preliminary in situ measurements of Jupiter's auroral regions yielded no evidence of such a process. Here we report observations of distinct, high-energy, downward, discrete electron acceleration in Jupiter's auroral polar regions. We also infer upward magnetic-field-aligned electric potentials of up to 400 kiloelectronvolts, an order of magnitude larger than the largest potentials observed at Earth. Despite the magnitude of these upward electric potentials and the expectations from observations at Earth, the downward energy flux from discrete acceleration is less at Jupiter than that caused by broadband or stochastic processes, with broadband and stochastic characteristics that are substantially different from those at Earth.

5.
Vestn Otorinolaringol ; 88(2): 10-16, 2023.
Artigo em Russo | MEDLINE | ID: mdl-37184548

RESUMO

The peculiarities of cochlear implant (CI) processor fitting in children with auditory neuropathy spectrum disorders (ANSD) were investigated. At the 1-st fitting of the CI processor a standard protocol of parameters was used in all patients, including patients with cochlear nerve hypoplasia. After the initial fitting session, the behavioral tonal thresholds with CI in 55% of patients were 30-35 dB, in 32.% of patients - 40-50 dB. After 3-6 months, 65% of children with ANSD showed significant progress in auditory-speech development, which made it possible to use the standard protocol of tuning parameters for them with the most comfortable and threshold levels of electrical stimulation adjusted according to the child's reactions. The best dynamics was observed in 2 children with presynaptic ANSD with a confirmed DFNB9 (OTOF) gene mutation. In 35% of children, there was no progress in distinguishing speech signals and instability of reactions to sounds persisted after 6 months using of CI and speech therapy training, despite the low tonal thresholds of hearing. In these children the coding strategy was changed, the stimulation frequency was reduced, and the pulse width was increased. This helped to improve the discrimination of sounds with CI and progress in the child's speech development. The results demonstrate that children with ANSD require more frequent correction of CI processor settings: 1st year - every 3 months, then at least 2 times a year until the optimal coding strategy and settings are achieved. To predict the effectiveness of CI and determine the optimal tactics for setting up the CI processor in patients with ANSD, the preoperative examination should include MRI of the cerebellopontine angle to detect anomalies of the cochlear nerve and genetic examination to identify mutations that cause hearing impairment in patients with ANSD.


Assuntos
Implante Coclear , Implantes Cocleares , Perda Auditiva Central , Perda Auditiva Neurossensorial , Criança , Humanos , Perda Auditiva Central/diagnóstico , Perda Auditiva Neurossensorial/diagnóstico , Perda Auditiva Neurossensorial/cirurgia
6.
Geophys Res Lett ; 49(23): e2022GL099285, 2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-37034391

RESUMO

The Juno spacecraft has been in orbit around Jupiter since 2016. Two flybys of Ganymede were executed in 2021, opportunities realized by evolution of Juno's polar orbit over the intervening 5 years. The geometry of the close flyby just prior to the 34th perijove pass by Jupiter brought the spacecraft inside Ganymede's unique magnetosphere. Juno's payload, designed to study Jupiter's magnetosphere, had ample dynamic range to study Ganymede's magnetosphere. The Juno radio system was used both for gravity measurements and for study of Ganymede's ionosphere. Remote sensing of Ganymede returned new results on geology, surface composition, and thermal properties of the surface and subsurface.

7.
Vestn Otorinolaringol ; 86(1): 30-35, 2021.
Artigo em Russo | MEDLINE | ID: mdl-33720648

RESUMO

THE AIM OF THE STUDY: Was to study the possibility of using a battery of psychoacoustic tests to assess the tuning of the cochlear implant processor (CI) in deaf patients. METHODOLOGY: The study involved 60 prellingually deaf patients aged 10 to 23 years with oral speech skills. To assess the quality of the CI processor tuning, in addition to traditional methods, a special battery of psychoacoustic tests was used. The first block of tests assessed the perception of the basic characteristics of sound signals (duration, temporal structure, spectrum, timbre) and was used to assess the initial setting. The second block of tests, intended for patients with experience using CI, included tasks to distinguish acoustically similar and dynamically changing signals, etc. RESULTS: At the end of the initial CI setup session, patients with short signal perception problems were identified. Adjusting the frequency of electrical stimulation in patients has increased their ability to distinguish between sounds. During the second tuning session of the CI processor, 6 months later, a group of patients with difficulties in perceiving acoustic information in the low-frequency range was identified - distinguishing melodic intervals, changing the pitch of sounds, highlighting the voice of the target speaker. The «problem¼ patients underwent additional correction of the CI processor setting and the corresponding auditory training, which improved the test performance and subjective perception of sounds. CONCLUSION: The use of psychoacoustic tests expands the possibilities of fine tuning the CI processor, taking into account the individual characteristics of the patient's auditory perception at different stages of CI use, especially in «problem¼ patients.


Assuntos
Implante Coclear , Implantes Cocleares , Surdez , Percepção da Fala , Adolescente , Adulto , Criança , Surdez/diagnóstico , Humanos , Psicoacústica , Adulto Jovem
8.
Geophys Res Lett ; 46(16): 9397-9404, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31762519

RESUMO

The polar orbit of Juno at Jupiter provides a unique opportunity to observe high-latitude energetic particle injections. We measure energy-dispersed impulsive injections of protons and electrons. Ion injection signatures are just as prevalent as electron signatures, contrary to previous equatorial observations. Included are previously unreported observations of high-energy banded structures believed to be remnants of much earlier injections, where the particles have had time to disperse around Jupiter. A model fit of the injections used to estimate timing fits the shape of the proton signatures better than it does the electron shapes, suggesting that electrons and protons are different in their abilities to escape the injection region. We present ultaviolet observations of Jupiter's aurora and discuss the relationship between auroral injection features and in situ injection events. We find, unexpectedly, that the presence of in situ particle injections does not necessarily result in auroral injection signatures.

9.
Geophys Res Lett ; 46(1): 19-27, 2019 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-30828110

RESUMO

We compare electron and UV observations mapping to the same location in Jupiter's northern polar region, poleward of the main aurora, during Juno perijove 5. Simultaneous peaks in UV brightness and electron energy flux are identified when observations map to the same location at the same time. The downward energy flux during these simultaneous observations was not sufficient to generate the observed UV brightness; the upward energy flux was. We propose that the primary acceleration region is below Juno's altitude, from which the more intense upward electrons originate. For the complete interval, the UV brightness peaked at ~240 kilorayleigh (kR); the downward and upward energy fluxes peaked at 60 and 700 mW/m2, respectively. Increased downward energy fluxes are associated with increased contributions from tens of keV electrons. These observations provide evidence that bidirectional electron beams with broad energy distributions can produce tens to hundreds of kilorayleigh polar UV emissions.

10.
Bull Exp Biol Med ; 167(1): 53-56, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31183657

RESUMO

The effect of the anti-inflammatory cytokine IL-10 on the ultrastructural distribution of AMPA receptor GluR1 subunit in CA1 field of cultured hippocampal slices was studied by using immunohistochemical technique. It was found that long-term posttetanic potentiation increased the content of GluR1 in the postsynaptic density of the axo-spinous synapse. Addition of IL-10 in concentrations of 1 and 10 ng/ml to the medium facilitated long-term posttetanic potentiation thereby changing the distribution of GluR1 in the spine: the number of receptors increased in the cytoplasm and decreased in the postsynaptic density. It is assumed that activation of neuronal IL-10 receptors affects the distribution of AMPA receptors in axo-spinous synapses of hippocampal field CA1 through interplay of intracellular signaling pathways, thereby participating in the mechanisms of synaptic plasticity under normal conditions.


Assuntos
Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Interleucina-10/farmacologia , Receptores de AMPA/metabolismo , Animais , Imuno-Histoquímica , Técnicas In Vitro , Potenciação de Longa Duração/efeitos dos fármacos , Masculino , Ratos , Ratos Wistar
11.
Vestn Otorinolaringol ; 84(2): 29-35, 2019.
Artigo em Russo | MEDLINE | ID: mdl-31198212

RESUMO

The efficacy of sequential bilateral cochlear implantation with long interval between surgeries (18 years) was investigated in deaf-blind patient (22 years old man, lost hearing and vision after meningitis at the age 2.5 years). At the age 4 years he got cochlear implant at right ear. His speech skills completely disappeared before the implantation. Auditory-speech rehabilitation with cochlear implant was successful - patient has good auditory, language, speech, cognitive skills. At the age 22 years patient made decision to get cochlear implant at the left ear after breakdown of internal part of cochlear implant at right ear in spite of successful reoperation. After activation of new processor (all electrodes were activated) the patient got daily auditory training with cochlear implant at left ear (Concerto/Opus 2, Medel) on the base of 'auditory' method, in daily life patient uses 2 devices. After 1 month of using cochlear implant at left ear the patient recognized environmental sounds and music instruments, words and sentences in close set tests EARS battery, the score for OLSA test in quiet was 90%, but the perception in noise was complicated. The balance of parameters of fitting for 1-st and 2-nd processors and special auditory training with two cochlear implants provided the development of initial binaural interaction. Perilinqually deaf patients can achieve high effect after sequential bilateral cochlear implantation with long interval between surgeries. The necessary conditions are - preservation of electrical activity of auditory nerve, intensive structured auditory training with new 'ear', patient's motivation of using of cochlear implant at 'new' ear.


Assuntos
Cegueira , Implante Coclear , Implantes Cocleares , Surdez , Perda Auditiva , Percepção da Fala , Adulto , Cegueira/complicações , Surdez/complicações , Humanos , Masculino , Resultado do Tratamento , Adulto Jovem
12.
Geophys Res Lett ; 44(15): 7668-7675, 2017 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-28989207

RESUMO

Juno ultraviolet spectrograph (UVS) observations of Jupiter's aurora obtained during approach are presented. Prior to the bow shock crossing on 24 June 2016, the Juno approach provided a rare opportunity to correlate local solar wind conditions with Jovian auroral emissions. Some of Jupiter's auroral emissions are expected to be controlled or modified by local solar wind conditions. Here we compare synoptic Juno-UVS observations of Jupiter's auroral emissions, acquired during 3-29 June 2016, with in situ solar wind observations, and related Jupiter observations from Earth. Four large auroral brightening events are evident in the synoptic data, in which the total emitted auroral power increases by a factor of 3-4 for a few hours. Only one of these brightening events correlates well with large transient increases in solar wind ram pressure. The brightening events which are not associated with the solar wind generally have a risetime of ~2 h and a decay time of ~5 h.

13.
Biochemistry (Mosc) ; 82(3): 264-274, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28320267

RESUMO

After accumulation of data showing that resident brain cells (neurons, astrocytes, and microglia) produce mediators of the immune system, such as cytokines and their receptors under normal physiological conditions, a critical need emerged for investigating the role of these mediators in cognitive processes. The major problem for understanding the functional role of cytokines in the mechanisms of synaptic plasticity, de novo neurogenesis, and learning and memory is the small number of investigated cytokines. Existing concepts are based on data from just three proinflammatory cytokines: interleukin-1 beta, interleukin-6, and tumor necrosis factor-alpha. The amount of information in the literature on the functional role of antiinflammatory cytokines in the mechanisms of synaptic plasticity and cognitive functions of mature mammalian brain is dismally low. However, they are of principle importance for understanding the mechanisms of local information processing in the brain, since they modulate the activity of individual cells and local neural networks, being able to reconstruct the processes of synaptic plasticity and intercellular communication, in general, depending on the local ratio of the levels of different cytokines in certain areas of the brain. Understanding the functional role of cytokines in cellular mechanisms of information processing and storage in the brain would allow developing preventive and therapeutic means for the treatment of neuropathologies related to impairment of these mechanisms.


Assuntos
Encéfalo/metabolismo , Citocinas/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Plasticidade Neuronal/fisiologia , Animais , Humanos
14.
Bull Exp Biol Med ; 160(5): 643-5, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27021102

RESUMO

We studied the contribution of large conductance Ca(2+)-activated potassium channels (BKCa) in the mechanisms of neuromodulatory effects of anti-inflammatory cytokine IL-10 on hypoxiainduced changes in activity of CA1 pyramidal neurons in rat hippocampus. We used the method of registration of population spikes from CA1 pyramidal neurons in hippocampal slices before, during, and after exposure to short-term episodes of hypoxia. Selective blocker (iberiotoxin) and selective activator of BKCa (BMS-191011) were used to evaluate the contribution of these channels in the mechanisms of suppressive effects of IL-10 on changes in neuronal activity during hypoxia and development of post-hypoxic hyperexcitability. It was shown that BKCa are involved in the modulatory effects of IL-10 on hypoxia-induced suppression of activity of CA1 pyramidal neurons in the hippocampus and development of post-hypoxic hyperexcitability in these neurons.


Assuntos
Hipóxia Celular/efeitos dos fármacos , Hipocampo/metabolismo , Interleucina-10/farmacologia , Subunidades alfa do Canal de Potássio Ativado por Cálcio de Condutância Alta/metabolismo , Células Piramidais/metabolismo , Animais , Hipocampo/citologia , Subunidades alfa do Canal de Potássio Ativado por Cálcio de Condutância Alta/agonistas , Subunidades alfa do Canal de Potássio Ativado por Cálcio de Condutância Alta/antagonistas & inibidores , Oxidiazóis/farmacologia , Peptídeos/farmacologia , Ratos , Ratos Wistar
15.
J Evol Biol ; 28(4): 756-65, 2015 04.
Artigo em Inglês | MEDLINE | ID: mdl-25772340

RESUMO

The evolution of multicellularity is a major transition that is not yet fully understood. Specifically, we do not know whether there are any mechanisms by which multicellularity can be maintained without a single-cell bottleneck or other relatedness-enhancing mechanisms. Under low relatedness, cheaters can evolve that benefit from the altruistic behaviour of others without themselves sacrificing. If these are obligate cheaters, incapable of cooperating, their spread can lead to the demise of multicellularity. One possibility, however, is that cooperators can evolve resistance to cheaters. We tested this idea in a facultatively multicellular social amoeba, Dictyostelium discoideum. This amoeba usually exists as a single cell but, when stressed, thousands of cells aggregate to form a multicellular organism in which some of the cells sacrifice for the good of others. We used lineages that had undergone experimental evolution at very low relatedness, during which time obligate cheaters evolved. Unlike earlier experiments, which found resistance to cheaters that were prevented from evolving, we competed cheaters and noncheaters that evolved together, and cheaters with their ancestors. We found that noncheaters can evolve resistance to cheating before cheating sweeps through the population and multicellularity is lost. Our results provide insight into cheater-resister coevolutionary dynamics, in turn providing experimental evidence for the maintenance of at least a simple form of multicellularity by means other than high relatedness.


Assuntos
Evolução Biológica , Dictyostelium/fisiologia
16.
J Math Biol ; 70(1-2): 329-41, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24570348

RESUMO

The role of fire in expanding the global distribution of savanna is well recognized. Empirical observations and modeling suggest that fire spread has a threshold response to fuel-layer continuity, which sets up a positive feedback that maintains savanna-forest bistability. However, modeling has so far failed to examine fire spread as a spatial process that interacts with vegetation. Here, we use simple, well-supported assumptions about fire spread as an infection process and its effects on trees to ask whether spatial dynamics qualitatively change the potential for savanna-forest bistability. We show that the spatial effects of fire spread are the fundamental reason that bistability is possible: because fire spread is an infection process, it exhibits a threshold response to fuel continuity followed by a rapid increase in fire size. Other ecological processes affecting fire spread may also contribute including temporal variability in demography or fire spread. Finally, including the potential for spatial aggregation increases the potential both for savanna-forest bistability and for savanna and forest to coexist in a landscape mosaic.


Assuntos
Incêndios , Florestas , Pradaria , Modelos Biológicos , Simulação por Computador , Ecossistema , Conceitos Matemáticos , Processos Estocásticos
17.
Psychol Med ; 44(1): 205-19, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23551932

RESUMO

BACKGROUND: Longitudinal symptoms of post-traumatic stress disorder (PTSD) are often characterized by heterogeneous trajectories, which may have unique pre-, peri- and post-trauma risk and protective factors. To date, however, no study has evaluated the nature and determinants of predominant trajectories of PTSD symptoms in World Trade Center (WTC) responders. METHOD: A total of 10835 WTC responders, including 4035 professional police responders and 6800 non-traditional responders (e.g. construction workers) who participated in the WTC Health Program (WTC-HP), were evaluated an average of 3, 6 and 8 years after the WTC attacks. RESULTS: Among police responders, longitudinal PTSD symptoms were best characterized by four classes, with the majority (77.8%) in a resistant/resilient trajectory and the remainder exhibiting chronic (5.3%), recovering (8.4%) or delayed-onset (8.5%) symptom trajectories. Among non-traditional responders, a six-class solution was optimal, with fewer responders in a resistant/resilient trajectory (58.0%) and the remainder exhibiting recovering (12.3%), severe chronic (9.5%), subsyndromal increasing (7.3%), delayed-onset (6.7%) and moderate chronic (6.2%) trajectories. Prior psychiatric history, Hispanic ethnicity, severity of WTC exposure and WTC-related medical conditions were most strongly associated with symptomatic trajectories of PTSD symptoms in both groups of responders, whereas greater education and family and work support while working at the WTC site were protective against several of these trajectories. CONCLUSIONS: Trajectories of PTSD symptoms in WTC responders are heterogeneous and associated uniquely with pre-, peri- and post-trauma risk and protective factors. Police responders were more likely than non-traditional responders to exhibit a resistant/resilient trajectory. These results underscore the importance of prevention, screening and treatment efforts that target high-risk disaster responders, particularly those with prior psychiatric history, high levels of trauma exposure and work-related medical morbidities.


Assuntos
Socorristas/psicologia , Resiliência Psicológica , Ataques Terroristas de 11 de Setembro/psicologia , Transtornos de Estresse Pós-Traumáticos/psicologia , Adulto , Estudos de Coortes , Socorristas/estatística & dados numéricos , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Polícia/estatística & dados numéricos , Estudos Prospectivos , Fatores de Risco , Apoio Social , Transtornos de Estresse Pós-Traumáticos/epidemiologia
18.
Psychol Med ; 44(10): 2085-98, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24289878

RESUMO

BACKGROUND: Post-traumatic stress disorder (PTSD) in response to the World Trade Center (WTC) disaster of 11 September 2001 (9/11) is one of the most prevalent and persistent health conditions among both professional (e.g. police) and non-traditional (e.g. construction worker) WTC responders, even several years after 9/11. However, little is known about the dimensionality and natural course of WTC-related PTSD symptomatology in these populations. METHOD: Data were analysed from 10 835 WTC responders, including 4035 police and 6800 non-traditional responders who were evaluated as part of the WTC Health Program, a clinic network in the New York area established by the National Institute for Occupational Safety and Health. Confirmatory factor analyses (CFAs) were used to evaluate structural models of PTSD symptom dimensionality; and autoregressive cross-lagged (ARCL) panel regressions were used to examine the prospective interrelationships among PTSD symptom clusters at 3, 6 and 8 years after 9/11. RESULTS: CFAs suggested that five stable symptom clusters best represent PTSD symptom dimensionality in both police and non-traditional WTC responders. This five-factor model was also invariant over time with respect to factor loadings and structural parameters, thereby demonstrating its longitudinal stability. ARCL panel regression analyses revealed that hyperarousal symptoms had a prominent role in predicting other symptom clusters of PTSD, with anxious arousal symptoms primarily driving re-experiencing symptoms, and dysphoric arousal symptoms primarily driving emotional numbing symptoms over time. CONCLUSIONS: Results of this study suggest that disaster-related PTSD symptomatology in WTC responders is best represented by five symptom dimensions. Anxious arousal symptoms, which are characterized by hypervigilance and exaggerated startle, may primarily drive re-experiencing symptoms, while dysphoric arousal symptoms, which are characterized by sleep disturbance, irritability/anger and concentration difficulties, may primarily drive emotional numbing symptoms over time. These results underscore the importance of assessment, monitoring and early intervention of hyperarousal symptoms in WTC and other disaster responders.


Assuntos
Socorristas/estatística & dados numéricos , Incidentes com Feridos em Massa/estatística & dados numéricos , Ataques Terroristas de 11 de Setembro/estatística & dados numéricos , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estados Unidos
19.
Br J Anaesth ; 113(4): 618-27, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24860157

RESUMO

BACKGROUND: Surgery in the beach chair position (BCP) may reduce cerebral blood flow and oxygenation, resulting in neurological injuries. The authors tested the hypothesis that a ventilation strategy designed to achieve end-tidal carbon dioxide (E'(CO2)) values of 40-42 mm Hg would increase cerebral oxygenation (Sct(O2)) during BCP shoulder surgery compared with a ventilation strategy designed to achieve E'(CO2) values of 30-32 mm Hg. METHODS: Seventy patients undergoing shoulder surgery in the BCP with general anaesthesia were enrolled in this randomized controlled trial. Mechanical ventilation was adjusted to maintain an E'(CO2) of 30-32 mm Hg in the control group and an E'(CO2) of 40-42 mm Hg in the study group. Cerebral oxygenation was monitored continuously in the operating theatre using near-infrared spectroscopy. Baseline haemodynamics and Sct(O2) were obtained before induction of anaesthesia, and these values were then measured and recorded continuously from induction of anaesthesia until tracheal extubation. The number of cerebral desaturation events (CDEs) (defined as a ≥20% reduction in Sct(O2) from baseline values) was recorded. RESULTS: No significant differences between the groups were observed in haemodynamic variables or phenylephrine interventions during the surgical procedure. Sct(O2) values were significantly higher in the study 40-42 group throughout the intraoperative period (P<0.01). In addition, the incidence of CDEs was lower in the study 40-42 group (8.8%) compared with the control 30-32 group (55.6%, P<0.0001). CONCLUSIONS: Cerebral oxygenation is significantly improved during BCP surgery when ventilation is adjusted to maintain E'(CO2) at 40-42 mm Hg compared with 30-32 mm Hg. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov NCT01546636.


Assuntos
Consumo de Oxigênio/fisiologia , Posicionamento do Paciente/métodos , Respiração Artificial/métodos , Adulto , Idoso , Anestesia Geral , Pressão Sanguínea/fisiologia , Dióxido de Carbono/sangue , Determinação de Ponto Final , Feminino , Frequência Cardíaca/fisiologia , Hemodinâmica/fisiologia , Humanos , Hipóxia/epidemiologia , Período Intraoperatório , Masculino , Pessoa de Meia-Idade , Fenilefrina/uso terapêutico , Complicações Pós-Operatórias/epidemiologia , Ombro/cirurgia , Espectroscopia de Luz Próxima ao Infravermelho , Vasoconstritores/uso terapêutico
20.
Can J Neurol Sci ; 41(2): 210-9, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24534033

RESUMO

BACKGROUND: the maternally inherited MTTL1 A3243G mutation in the mitochondrial genome causes MelaS (Mitochondrial encephalopathy lactic acidosis with Stroke-like episodes), a condition that is multisystemic but affects primarily the nervous system. Significant intra-familial variation in phenotype and severity of disease is well recognized. METHODS: retrospective and ongoing study of an extended family carrying the MTTL1 A3243G mutation with multiple symptomatic individuals. tissue heteroplasmy is reviewed based on the clinical presentations, imaging studies, laboratory findings in affected individuals and pathological material obtained at autopsy in two of the family members. RESULTS: there were seven affected individuals out of thirteen members in this three generation family who each carried the MTTL1 A3243G mutation. the clinical presentations were varied with symptoms ranging from hearing loss, migraines, dementia, seizures, diabetes, visual manifestations, and stroke like episodes. three of the family members are deceased from MelaS or to complications related to MelaS. CONCLUSIONS: the results of the clinical, pathological and radiological findings in this family provide strong support to the current concepts of maternal inheritance, tissue heteroplasmy and molecular pathogenesis in MelaS. neurologists (both adult and paediatric) are the most likely to encounter patients with MelaS in their practice. genetic counselling is complex in view of maternal inheritance and heteroplasmy. newer therapeutic options such as arginine are being used for acute and preventative management of stroke like episodes.


Assuntos
Encéfalo/patologia , Genes Mitocondriais/genética , Síndrome MELAS/genética , Músculo Esquelético/patologia , RNA de Transferência de Leucina/genética , Adolescente , Adulto , Criança , Demência/genética , Demência/fisiopatologia , Diabetes Mellitus/genética , Diabetes Mellitus/fisiopatologia , Feminino , Perda Auditiva/genética , Perda Auditiva/fisiopatologia , Humanos , Síndrome MELAS/patologia , Síndrome MELAS/fisiopatologia , Masculino , Pessoa de Meia-Idade , Transtornos de Enxaqueca/genética , Transtornos de Enxaqueca/fisiopatologia , Mutação , Linhagem , Fenótipo , Estudos Retrospectivos , Convulsões/genética , Convulsões/fisiopatologia , Acidente Vascular Cerebral/genética , Acidente Vascular Cerebral/fisiopatologia , Transtornos da Visão/genética , Transtornos da Visão/fisiopatologia , Adulto Jovem
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