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1.
Anaesth Rep ; 12(1): e12294, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38708145

RESUMO

Worldwide, breast cancer is the most commonly diagnosed cancer in women. Surgical procedures are typically performed using general anaesthesia, often complemented by regional anaesthesia to manage postoperative pain. However, avoidance of general anaesthesia for breast surgery may be desirable for clinical reasons or patient choice. It is theorised that the use of regional anaesthesia and the avoidance of volatile anaesthetics and opioid analgesia may have beneficial effects on oncological outcomes, and there is some evidence to support this. While many patients successfully undergo awake breast surgery, a limited number of anaesthetists possess direct experience of this approach, despite familiarity with regional anaesthesia techniques. Undertaking regional anaesthesia for awake breast surgery requires patient cooperation and excellent staff teamwork. Here, we present a case of a patient who underwent awake bilateral mastectomy with reconstruction. This was carried out under two 'paravertebral-by-proxy' blocks: the thoracic erector spinae plane and inter-transverse plane blocks, with intravenous sedation.

2.
Phys Rev Lett ; 126(20): 201102, 2021 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-34110215

RESUMO

The measurement of the energy spectrum of cosmic ray helium nuclei from 70 GeV to 80 TeV using 4.5 years of data recorded by the Dark Matter Particle Explorer (DAMPE) is reported in this work. A hardening of the spectrum is observed at an energy of about 1.3 TeV, similar to previous observations. In addition, a spectral softening at about 34 TeV is revealed for the first time with large statistics and well controlled systematic uncertainties, with an overall significance of 4.3σ. The DAMPE spectral measurements of both cosmic protons and helium nuclei suggest a particle charge dependent softening energy, although with current uncertainties a dependence on the number of nucleons cannot be ruled out.

4.
Sci Adv ; 5(9): eaax3793, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31799401

RESUMO

The precise measurement of the spectrum of protons, the most abundant component of the cosmic radiation, is necessary to understand the source and acceleration of cosmic rays in the Milky Way. This work reports the measurement of the cosmic ray proton fluxes with kinetic energies from 40 GeV to 100 TeV, with 2 1/2 years of data recorded by the DArk Matter Particle Explorer (DAMPE). This is the first time that an experiment directly measures the cosmic ray protons up to ~100 TeV with high statistics. The measured spectrum confirms the spectral hardening at ~300 GeV found by previous experiments and reveals a softening at ~13.6 TeV, with the spectral index changing from ~2.60 to ~2.85. Our result suggests the existence of a new spectral feature of cosmic rays at energies lower than the so-called knee and sheds new light on the origin of Galactic cosmic rays.

5.
BMC Cancer ; 19(1): 970, 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31638925

RESUMO

BACKGROUND: Neuroblastoma (NB) is a paediatric tumour of the sympathetic nervous system. Half of all cases are defined high-risk with an overall survival less than 40% at 5 years from diagnosis. The lack of in vitro models able to recapitulate the intrinsic heterogeneity of primary NB tumours has hindered progress in understanding disease pathogenesis and therapy response. METHODS: Here we describe the establishment of 6 patient-derived organoids (PDOs) from cells of NB tumour biopsies capable of self-organising in a structure resembling the tissue of origin. RESULTS: PDOs recapitulate the histological architecture typical of the NB tumour. Moreover, PDOs expressed NB specific markers such as neural cell adhesion molecules, NB84 antigen, synaptophysin (SYP), chromogranin A (CHGA) and neural cell adhesion molecule NCAM (CD56). Analyses of whole genome genotyping array revealed that PDOs maintained patient-specific chromosomal aberrations such as MYCN amplification, deletion of 1p and gain of chromosome 17q. Furthermore, the PDOs showed stemness features and retained cellular heterogeneity reflecting the high heterogeneity of NB tumours. CONCLUSIONS: We were able to create a novel preclinical model for NB exhibiting self-renewal property and allowing to obtain a reservoir of NB patients' biological material useful for the study of NB molecular pathogenesis and to test drugs for personalised treatments.


Assuntos
Doenças do Sistema Nervoso Autônomo/genética , Doenças do Sistema Nervoso Autônomo/patologia , Modelos Biológicos , Neuroblastoma/genética , Neuroblastoma/patologia , Organoides/patologia , Doenças do Sistema Nervoso Autônomo/metabolismo , Biomarcadores Tumorais/metabolismo , Biópsia , Criança , Pré-Escolar , Cromogranina A/metabolismo , Aberrações Cromossômicas , Amplificação de Genes/genética , Humanos , Lactente , Proteína Proto-Oncogênica N-Myc/genética , Neuroblastoma/metabolismo , Organoides/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Sinaptofisina/metabolismo
6.
Phys Rev Lett ; 121(24): 241101, 2018 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-30608723

RESUMO

The gamma-ray sky has been observed with unprecedented accuracy in the last decade by the Fermi -large area telescope (LAT), allowing us to resolve and understand the high-energy Universe. The nature of the remaining unresolved emission [unresolved gamma-ray background (UGRB)] below the LAT source detection threshold can be uncovered by characterizing the amplitude and angular scale of the UGRB fluctuation field. This Letter presents a measurement of the UGRB autocorrelation angular power spectrum based on eight years of Fermi-LAT Pass 8 data products. The analysis is designed to be robust against contamination from resolved sources and noise systematics. The sensitivity to subthreshold sources is greatly enhanced with respect to previous measurements. We find evidence (with ∼3.7σ significance) that the scenario in which two classes of sources contribute to the UGRB signal is favored over a single class. A double power law with exponential cutoff can explain the anisotropy energy spectrum well, with photon indices of the two populations being 2.55±0.23 and 1.86±0.15.

7.
Astrophys J ; 863(2)2018 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-35027772

RESUMO

We use joint observations by the Neil Gehrels Swift X-ray Telescope (XRT) and the Fermi Large Area Telescope (LAT) of gamma-ray burst (GRB) afterglows to investigate the nature of the long-lived high-energy emission observed by Fermi LAT. Joint broadband spectral modeling of XRT and LAT data reveal that LAT non-detections of bright X-ray afterglows are consistent with a cooling break in the inferred electron synchrotron spectrum below the LAT and/or XRT energy ranges. Such a break is sufficient to suppress the high-energy emission so as to be below the LAT detection threshold. By contrast, LAT-detected bursts are best fit by a synchrotron spectrum with a cooling break that lies either between or above the XRT and LAT energy ranges. We speculate that the primary difference between GRBs with LAT afterglow detections and the non-detected population may be in the type of circumstellar environment in which these bursts occur, with late-time LAT detections preferentially selecting GRBs that occur in low wind-like circumburst density profiles. Furthermore, we find no evidence of high-energy emission in the LAT-detected population significantly in excess of the flux expected from the electron synchrotron spectrum fit to the observed X-ray emission. The lack of excess emission at high energies could be due to a shocked external medium in which the energy density in the magnetic field is stronger than or comparable to that of the relativistic electrons behind the shock, precluding the production of a dominant synchrotron self-Compton (SSC) component in the LAT energy range. Alternatively, the peak of the SSC emission could be beyond the 0.1-100 GeV energy range considered for this analysis.

8.
Int J Surg ; 41 Suppl 1: S48-S54, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28506413

RESUMO

BACKGROUND: Acute respiratory failure is a rare life threatening complication following thyroid surgery and its incidence is reported as high as 0.9%. Clinical presentation of severe acute respiratory failure is characterized by dyspnea, inspiratory airways distress, hypoxia and its standard current management is the orotracheal intubation and safe extubation. In case of persistent distress, tracheotomy is mandatory. The Authors, analysing a large acute respiratory failure clinical series, describe an innovative treatment of this severe condition: the nasotracheal prolonged safe extubation. METHODS: Patients treated at our Intensive Care Unit for acute respiratory failure following thyroid surgery from January 2004 to December 2013, were reviewed. Demographic data including gender, age, clinical presentation, laryngoscopic findings, management and outcome during a 24-months follow-up after treatment were collected and evaluated. Moreover, the strategy for prolonged nasotracheal safe extubation was carefully described. RESULTS: Nineteen out of the 2853 patients scheduled for thyroid surgery (0.66%) at our University Hospital, developed post-operative acute respiratory failure. All of them were treated by nasotracheal prolonged safe extubation. The success rate in avoiding highly invasive treatment was of 84.2%, since only 3 patients needed definitive tracheotomy (15.7%). CONCLUSIONS: In our series, the prolonged safe extubation reduced the almost totality of expected tracheotomies in patients with acute respiratory failure following thyroid surgery (84.2%), demonstrating its feasibility and efficacy. It was a well tolerated and minimal invasive procedure that allowed a good respiratory ability and a fast clinical resolution of the laryngeal functional impairment.


Assuntos
Extubação/métodos , Intubação Intratraqueal/métodos , Complicações Pós-Operatórias/terapia , Insuficiência Respiratória/terapia , Tireoidectomia/efeitos adversos , Adulto , Idoso , Estudos de Viabilidade , Feminino , Seguimentos , Humanos , Unidades de Terapia Intensiva , Laringoscopia , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Período Pós-Operatório , Insuficiência Respiratória/etiologia , Estudos Retrospectivos , Fatores de Tempo , Traqueotomia/estatística & dados numéricos
9.
Phys Rev Lett ; 118(9): 091103, 2017 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-28306280

RESUMO

The Large Area Telescope on board the Fermi Gamma-ray Space Telescope has collected the largest ever sample of high-energy cosmic-ray electron and positron events since the beginning of its operation. Potential anisotropies in the arrival directions of cosmic-ray electrons or positrons could be a signature of the presence of nearby sources. We use almost seven years of data with energies above 42 GeV processed with the Pass 8 reconstruction. The present data sample can probe dipole anisotropies down to a level of 10^{-3}. We take into account systematic effects that could mimic true anisotropies at this level. We present a detailed study of the event selection optimization of the cosmic-ray electrons and positrons to be used for anisotropy searches. Since no significant anisotropies have been detected on any angular scale, we present upper limits on the dipole anisotropy. The present constraints are among the strongest to date probing the presence of nearby young and middle-aged sources.

10.
Phys Rev Lett ; 116(16): 161101, 2016 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-27152783

RESUMO

We report on the search for spectral irregularities induced by oscillations between photons and axionlike-particles (ALPs) in the γ-ray spectrum of NGC 1275, the central galaxy of the Perseus cluster. Using 6 years of Fermi Large Area Telescope data, we find no evidence for ALPs and exclude couplings above 5×10^{-12} GeV^{-1} for ALP masses 0.5≲m_{a}≲5 neV at 95% confidence. The limits are competitive with the sensitivity of planned laboratory experiments, and, together with other bounds, strongly constrain the possibility that ALPs can reduce the γ-ray opacity of the Universe.

11.
J Orthop ; 13(3): 119-22, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27076741

RESUMO

BACKGROUND: Total knee arthroplasty (TKA) can result in major postoperative pain which can impact the recovery and rehabilitation of patients and for this reason the use of a pain-control infusion pumps (PCIP) enhances analgesia for TKA. PURPOSE: To investigate whether a PCIP of levobupivacaine would reduce pain in patients following TKA. METHODS: This was a prospective, randomized, controlled study conducted in 55 patients. Criteria for participation were unilateral TKA for osteoarthritis and no allergies to levobupivacaine. The primary outcomes measured were postoperative pain intensity on Visual Analogue Scale (VAS) score measured at 24 h and 48 h. Other measures included amount of narcotics, presence of adverse events, and length of hospital stay. RESULTS: PCIP-treated patients (n = 28) showed significant reductions in VAS score at any time versus control (p < 0.01). Amount of narcotics, presence of adverse events, and length of hospital stay were significantly less with the PCIP versus control (each p < 0.01). CONCLUSION: The use of a mix of levobupivacaina, ketoral-trometamina, and adrenalin provides a safe and effective means in post-operative pain relief in patients undergoing TKA. LEVEL OF EVIDENCE: Level II therapeutic study.

12.
Phys Rev Lett ; 116(15): 151105, 2016 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-27127954

RESUMO

The Fermi Large Area Telescope (LAT) Collaboration has recently released a catalog of 360 sources detected above 50 GeV (2FHL). This catalog was obtained using 80 months of data re-processed with Pass 8, the newest event-level analysis, which significantly improves the acceptance and angular resolution of the instrument. Most of the 2FHL sources at high Galactic latitude are blazars. Using detailed Monte Carlo simulations, we measure, for the first time, the source count distribution, dN/dS, of extragalactic γ-ray sources at E>50 GeV and find that it is compatible with a Euclidean distribution down to the lowest measured source flux in the 2FHL (∼8×10^{-12} ph cm^{-2} s^{-1}). We employ a one-point photon fluctuation analysis to constrain the behavior of dN/dS below the source detection threshold. Overall, the source count distribution is constrained over three decades in flux and found compatible with a broken power law with a break flux, S_{b}, in the range [8×10^{-12},1.5×10^{-11}] ph cm^{-2} s^{-1} and power-law indices below and above the break of α_{2}∈[1.60,1.75] and α_{1}=2.49±0.12, respectively. Integration of dN/dS shows that point sources account for at least 86_{-14}^{+16}% of the total extragalactic γ-ray background. The simple form of the derived source count distribution is consistent with a single population (i.e., blazars) dominating the source counts to the minimum flux explored by this analysis. We estimate the density of sources detectable in blind surveys that will be performed in the coming years by the Cherenkov Telescope Array.

13.
Phys Rev D ; 93(8): 082001, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32743154

RESUMO

We have measured the gamma-ray emission spectrum of the Moon using the data collected by the Large Area Telescope onboard the Fermi satellite during its first seven years of operation, in the energy range from 30 MeV up to a few GeV. We have also studied the time evolution of the flux, finding a correlation with the solar activity. We have developed a full Monte Carlo simulation describing the interactions of cosmic rays with the lunar surface. The results of the present analysis can be explained in the framework of this model, where the production of gamma rays is due to the interactions of cosmic-ray proton and helium nuclei with the surface of the Moon. Finally, we have used our simulation to derive the cosmic-ray proton and helium spectra near Earth from the Moon gamma-ray data.

14.
Am J Physiol Cell Physiol ; 308(2): C123-38, 2015 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-25354526

RESUMO

Muscle-specific ankyrins 1 (sAnk1) are a group of small ankyrin 1 isoforms, of which sAnk1.5 is the most abundant. sAnk1 are localized in the sarcoplasmic reticulum (SR) membrane from where they interact with obscurin, a myofibrillar protein. This interaction appears to contribute to stabilize the SR close to the myofibrils. Here we report the structural and functional characterization of skeletal muscles from sAnk1 knockout mice (KO). Deletion of sAnk1 did not change the expression and localization of SR proteins in 4- to 6-mo-old sAnk1 KO mice. Structurally, the main modification observed in skeletal muscles of adult sAnk1 KO mice (4-6 mo of age) was the reduction of SR volume at the sarcomere A band level. With increasing age (at 12-15 mo of age) extensor digitorum longus (EDL) skeletal muscles of sAnk1 KO mice develop prematurely large tubular aggregates, whereas diaphragm undergoes significant structural damage. Parallel functional studies revealed specific changes in the contractile performance of muscles from sAnk1 KO mice and a reduced exercise tolerance in an endurance test on treadmill compared with control mice. Moreover, reduced Qγ charge and L-type Ca(2+) current, which are indexes of affected excitation-contraction coupling, were observed in diaphragm fibers from 12- to 15-mo-old mice, but not in other skeletal muscles from sAnk1 KO mice. Altogether, these findings show that the ablation of sAnk1, by altering the organization of the SR, renders skeletal muscles susceptible to undergo structural and functional alterations more evident with age, and point to an important contribution of sAnk1 to the maintenance of the longitudinal SR architecture.


Assuntos
Envelhecimento/metabolismo , Anquirinas/genética , Anquirinas/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Isoformas de Proteínas/metabolismo , Deleção de Sequência/genética , Envelhecimento/genética , Animais , Canais de Cálcio Tipo L/genética , Canais de Cálcio Tipo L/metabolismo , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Contração Muscular/genética , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Isoformas de Proteínas/genética , Retículo Sarcoplasmático/genética , Retículo Sarcoplasmático/metabolismo
15.
Minerva Anestesiol ; 81(2): 195-204, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24739207

RESUMO

Cesarean delivery is a major surgical procedure, after which a woman can experience substantial postoperative discomfort or pain. Inadequate postoperative analgesia is one of the most common reasons for poor patient satisfaction following cesarean delivery. Although spinal or systemic opioids are currently the gold standard to achieve effective analgesia, they are often associated with side effects. In the last few years there has been growing interest in abdominal plane blocks, with promising data on their efficacy. The transversus abdominis plane (TAP) block is a regional analgesic technique which is gaining acceptance in postoperative analgesia for lower abdominal surgeries. In this systematic review of articles published as of 31 December 2013, we searched the principal medical databases for randomized controlled trials that assessed the efficacy of ultrasound (US)-guided TAP block following cesarean delivery and reported on postoperative opioid consumption and pain score, opioid-related side-effects and patient satisfaction. Although controversy surrounds the utility of US-guided TAP block in cesarean section, evidence suggests that when correctly executed as part of a multimodal analgesic regimen, TAP block may reduce postoperative opioid consumption and opioid-related side effects, improving postoperative pain control and patient satisfaction. Further studies are necessary to explore this field of research.


Assuntos
Cesárea/métodos , Bloqueio Nervoso/métodos , Dor Pós-Operatória/tratamento farmacológico , Músculos Abdominais , Adulto , Analgesia/métodos , Feminino , Humanos , Gravidez
16.
Drug Des Devel Ther ; 8: 2213-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25395837

RESUMO

AIM: To evaluate the effectiveness of a caval vein filter (CVF) peri-implant monitoring protocol in order to reduce pulmonary embolism (PE) mortality and CVF-related morbidity. BACKGROUND: The reduction in mortality from PE associated with the use of CVF is affected by the risk of increase in morbidity. Therefore, CVF implant is a challenging prophylactic or therapeutic option. Nowadays, we have many different devices whose rational use, by applying a strict peri-implant monitoring protocol, could be safe and effective. MATERIALS AND METHODS: We retrospectively studied 62 patients of a general Intensive Care Unit (ICU) scheduled for definitive, temporary, or optional bedside CVF implant. A peri-implant monitoring protocol including a phlebocavography, an echo-Doppler examination, and coagulation tests was adopted. RESULTS: In our study, no thromboembolic recurrence was registered. We implanted 48 retrievable and only 20 definitive CVFs. Endothelial adhesion (18%), residual clot (5%), cranial or caudal migration (6%), microbial colonization of the filter in the absence of clinical signs of infection (1%), caval thrombosis (1%), and pneumothorax (1%) were reported. Deep-vein thrombosis (DVT) was reported (8%) as early complication. All patients with DVT had a temporary or optional filter implanted. However, in our cohort, definitive CVFs were reserved only to 32% of patients and they were not associated with DVT as complication. CONCLUSION: CVF significantly reduces iatrogenic PE without affecting mortality. Generally, ICU patients have a transitory thromboembolic risk, and so the temporary CVF has been proved to be a first-line option to our cohort. A careful monitoring may contribute to a satisfactory outcome in order to promote CVF implant as a safe prophylaxis option.


Assuntos
Cuidados Críticos , Filtros de Veia Cava , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Embolia Pulmonar/mortalidade , Embolia Pulmonar/prevenção & controle , Estudos Retrospectivos , Trombose Venosa/complicações , Adulto Jovem
17.
Astrophys J ; 784(2)2014 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-34646038

RESUMO

Observations of occultations of bright γ-ray sources by the Sun may reveal predicted pair halos around blazars and/or new physics, such as, e.g., hypothetical light dark matter particles-axions. We use Fermi Gamma-Ray Space Telescope (Fermi) data to analyze four occultations of blazar 3C 279 by the Sun on October 8 each year from 2008 to 2011. A combined analysis of the observations of these occultations allows a point-like source at the position of 3C 279 to be detected with significance of ≈3σ, but does not reveal any significant excess over the flux expected from the quiescent Sun. The likelihood ratio test rules out complete transparency of the Sun to the blazar γ-ray emission at a 3σ confidence level.

18.
Science ; 338(6111): 1190-2, 2012 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-23118013

RESUMO

The light emitted by stars and accreting compact objects through the history of the universe is encoded in the intensity of the extragalactic background light (EBL). Knowledge of the EBL is important to understand the nature of star formation and galaxy evolution, but direct measurements of the EBL are limited by galactic and other foreground emissions. Here, we report an absorption feature seen in the combined spectra of a sample of gamma-ray blazars out to a redshift of z ∼ 1.6. This feature is caused by attenuation of gamma rays by the EBL at optical to ultraviolet frequencies and allowed us to measure the EBL flux density in this frequency band.

19.
Phys Rev Lett ; 108(1): 011103, 2012 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-22304252

RESUMO

We measured separate cosmic-ray electron and positron spectra with the Fermi Large Area Telescope. Because the instrument does not have an onboard magnet, we distinguish the two species by exploiting Earth's shadow, which is offset in opposite directions for opposite charges due to Earth's magnetic field. We estimate and subtract the cosmic-ray proton background using two different methods that produce consistent results. We report the electron-only spectrum, the positron-only spectrum, and the positron fraction between 20 and 200 GeV. We confirm that the fraction rises with energy in the 20-100 GeV range. The three new spectral points between 100 and 200 GeV are consistent with a fraction that is continuing to rise with energy.

20.
Science ; 334(6059): 1103-7, 2011 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-22116880

RESUMO

The origin of Galactic cosmic rays is a century-long puzzle. Indirect evidence points to their acceleration by supernova shockwaves, but we know little of their escape from the shock and their evolution through the turbulent medium surrounding massive stars. Gamma rays can probe their spreading through the ambient gas and radiation fields. The Fermi Large Area Telescope (LAT) has observed the star-forming region of Cygnus X. The 1- to 100-gigaelectronvolt images reveal a 50-parsec-wide cocoon of freshly accelerated cosmic rays that flood the cavities carved by the stellar winds and ionization fronts from young stellar clusters. It provides an example to study the youth of cosmic rays in a superbubble environment before they merge into the older Galactic population.

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