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1.
Opt Express ; 31(24): 40557-40572, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-38041353

RESUMO

Ocean reflectance inversion algorithms provide many products used in ecological and biogeochemical models. While a number of different inversion approaches exist, they all use only spectral remote-sensing reflectances (Rrs(λ)) as input to derive inherent optical properties (IOPs) in optically deep oceanic waters. However, information content in Rrs(λ) is limited, so spectral inversion algorithms may benefit from additional inputs. Here, we test the simplest possible case of ingesting optical data ('seeding') within an inversion scheme (the Generalized Inherent Optical Property algorithm framework default configuration (GIOP-DC)) with both simulated and satellite datasets of an independently known or estimated IOP, the particulate backscattering coefficient at 532 nm (bbp(532)). We find that the seeded-inversion absorption products are substantially different and more accurate than those generated by the standard implementation. On global scales, seasonal patterns in seeded-inversion absorption products vary by more than 50% compared to absorption from the GIOP-DC. This study proposes one framework in which to consider the next generation of ocean color inversion schemes by highlighting the possibility of adding information collected with an independent sensor.

2.
Phys Rev Lett ; 131(22): 226503, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38101342

RESUMO

Our measurements of ^{125}Te NMR relaxations reveal an enhancement of electronic spin fluctuations above µ_{0}H^{*}∼15 T, leading to their divergence in the vicinity of the metamagnetic transition at µ_{0}H_{m}≈35 T, below which field-reinforced superconductivity appears when a magnetic field (H) is applied along the crystallographic b axis. The NMR data evidence that these fluctuations are dominantly longitudinal, providing a key to understanding the peculiar superconducting phase diagram in H∥b, where such fluctuations enhance the pairing interactions.

3.
Nature ; 545(7655): 472-476, 2017 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-28467819

RESUMO

Mantle plumes are buoyant upwellings of hot rock that transport heat from Earth's core to its surface, generating anomalous regions of volcanism that are not directly associated with plate tectonic processes. The best-studied example is the Hawaiian-Emperor chain, but the emergence of two sub-parallel volcanic tracks along this chain, Loa and Kea, and the systematic geochemical differences between them have remained unexplained. Here we argue that the emergence of these tracks coincides with the appearance of other double volcanic tracks on the Pacific plate and a recent azimuthal change in the motion of the plate. We propose a three-part model that explains the evolution of Hawaiian double-track volcanism: first, mantle flow beneath the rapidly moving Pacific plate strongly tilts the Hawaiian plume and leads to lateral separation between high- and low-pressure melt source regions; second, the recent azimuthal change in Pacific plate motion exposes high- and low-pressure melt products as geographically distinct volcanoes, explaining the simultaneous emergence of double-track volcanism across the Pacific; and finally, secondary pyroxenite, which is formed as eclogite melt reacts with peridotite, dominates the low-pressure melt region beneath Loa-track volcanism, yielding the systematic geochemical differences observed between Loa- and Kea-type lavas. Our results imply that the formation of double-track volcanism is transitory and can be used to identify and place temporal bounds on plate-motion changes.

4.
Acta Oncol ; 60(3): 353-360, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33522851

RESUMO

BACKGROUND: In radiotherapy (RT) of lung cancer, dose to functional lung (FL) volumes segmented with two different methods (perfusion SPECT (Q-SPECT) and 4D-CT (4D) ventilation (V)) have been shown to correlate with the incidence of radiation pneumonitis (RP). This study aims to compare the FL volumes identified by both methods. MATERIAL AND METHODS: Thirty lung cancer patients had a 4D and Q-SPECT prior to treatment. Seventeen of these patients also had a ventilation SPECT (V-SPECT). FL sub-volumes were segmented automatically, using cut-off values. The volumes were compared in terms of overlap fraction (OF) relative to the minimal volume, and intersection fraction (IF) of the FL volume relative to the total lung volume (VLung). RESULTS: Cut-off values suggested in literature for Q-SPECT and 4D-V resulted in volumes differing in size by a median 18% [6%;31%], and a median OF and IF of 0.48 [0.23;0.70] and 0.09 [0.02;0.25], respectively. Segmenting volumes of comparable size of about 1/3 of VLung (FL-m(1/3), m = method) resulted in a median OF and IF of 0.43 [0.23;0.58] and 0.12 [0.06;0.19], respectively. Twenty-five patients (83%) had a reasonable overlap between FL-Q(1/3) and FL-4D-V(1/3) volumes, with OF values above 0.33. IF increased significantly (p = .036) compared to using fixed cut-off values. Similarly, volumes of comparable size of about 1/3 VLung were produced for V-SPECT, and FL-Q(1/3), FL-V(1/3), and FL-4D-V(1/3) were compared. The overlaps and intersections of FL-V(1/3) with FL-Q(1/3) volumes were significantly (p<.001) larger than the corresponding overlaps and intersections of FL-Q(1/3) with FL-4D(1/3) and FL-V(1/3) with FL-4D(1/3). CONCLUSION: The Q-SPECT and 4D-V methods do not segment entirely the same FL volumes. A reasonable overlap of the volumes along with the findings of other studies that both correlate to RP incidence, suggests that a combination of both volumes, e.g. using the IF, may be useful in RT treatment planning.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Pneumonite por Radiação , Tomografia Computadorizada Quadridimensional , Humanos , Pulmão/diagnóstico por imagem , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/radioterapia , Pneumonite por Radiação/etiologia , Tomografia Computadorizada de Emissão de Fóton Único
5.
Acta Oncol ; 60(9): 1091-1099, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34313177

RESUMO

BACKGROUND: Decisions regarding tumor staging, operability, resectability, and treatment strategy in patients with esophageal cancer are made at multidisciplinary team (MDT) conferences. We aimed to assess interobserver agreement from four national MDT conferences and whether this would have a clinical impact. METHODS: A total of 20 patients with esophageal cancer were included across all four upper gastrointestinal (GI) cancer centers. Fully anonymized patient data were distributed among the MDT conferences which decided on TNM category, resectability, operability, curability, and treatment strategy blinded to each other's decisions. The interobserver agreement was expressed as both the raw observer agreement and with Krippendorff's α values. Finally, a case-by-case evaluation was performed to determine if disagreement would have had a clinical impact. RESULTS: A total of 80 MDT evaluations were available for analysis. A moderate to near-perfect observer agreement of 79.2%, 55.8%, and 82.5% for TNM category was observed, respectively. Substantial agreement for resectability and moderate agreement for curability were found. However, an only fair agreement was observed for the operability category. The treatment strategies had a slight agreement which corresponded to disagreement having a clinical impact in 12 patients. CONCLUSIONS: Esophageal cancer MDT conferences had an acceptable interobserver agreement on resectability and TM categories; however, the operability assessment had a high level of disagreement. Consequently, the agreement on treatment strategy was reduced with a potential clinical impact. In future MDT conferences, emphasis should be on prioritizing the relevant information being readily available (operability, T & M categories) to minimize the risk of disagreement in the assessments and treatment strategies, and thus, delayed or suboptimal treatment.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Neoplasias de Cabeça e Pescoço , Neoplasias Esofágicas/terapia , Humanos , Equipe de Assistência ao Paciente , Estudos Prospectivos
6.
Eur Arch Otorhinolaryngol ; 278(8): 2781-2788, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32949303

RESUMO

OBJECTIVE: The ADHEAR system (MED-EL, Innsbruck, Austria) is a new adhesive bone conduction hearing aid. This study evaluates the audiological benefit and subjective satisfaction as well as the manageability in everyday life in children with unilateral conductive hearing loss. METHODS: Ten children with unilateral hearing loss of different origin were included in the study. The audiological assessment included sound field audiometry and speech intelligibility in quiet and in noise, which was tested unaided and after 4 weeks of wearing the hearing system. Subjective benefit and satisfaction with the system was assessed using the SSQ for parents. With a second system-specific questionnaire, suitability for everyday use and quality of life were queried. RESULTS: With ADHEAR, speech perception in quiet improved by 44%. The word recognition score in noise improved from 11.7% in the unaided situation to 46.7% with the ADHEAR system. The SSQ for parents demonstrates a subjective benefit and satisfaction with the system. CONCLUSION: ADHEAR is an effective treatment option for children with unilateral conductive hearing loss. Especially children who are not eligible for semi-implantable hearing systems or do not accept hearing devices on a softband can benefit from this device.


Assuntos
Auxiliares de Audição , Perda Auditiva Unilateral , Percepção da Fala , Áustria , Condução Óssea , Criança , Audição , Perda Auditiva Condutiva , Humanos , Satisfação Pessoal , Qualidade de Vida
7.
HNO ; 69(8): 633-641, 2021 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-33502578

RESUMO

BACKGROUND: From spring 2020, SARS-CoV­2 began to spread worldwide, with what is now known as the first wave of the pandemic, starting in March 2020. This resulted in restructuring and shift of resources at many hospitals. The aim of our work was to detect the effects of the pandemic on the german Oto-Rhino-Laryngology (ORL) university hospitals in terms of research, student teaching and further specialist training. MATERIAL AND METHODS: The chairmen of the 39 ORL university hospitals in Germany were asked about the effects of the pandemic on research, student teaching and ORL specialist training (residency) in the period from March to April 2020 using a structured online survey. RESULTS: All 39 chairmen took part in the survey. Of these, 74.4% (29/39) stated that their research activities had deteriorated as a result of the pandemic. In 61.5% (24/39) pandemic-related research issues were addressed. All hospitals reported a restriction for in-house teaching and 97.5% (38/39) introduced new digital teaching methods. During the observation period, 74.4% of the chairmen did not see ORL specialist training (residency)at risk. CONCLUSION: Our results provide an insight into the heterogeneous effects of the pandemic. The fast processing of pandemic-related research topics and the introduction of innovative digital concepts for student teaching impressively demonstrates the great innovative potential and the ability of the ORL university hospitals to react quickly in order to maintain their tasks in research, student teaching and ORL specialist training in the best possible way even during the pandemic.


Assuntos
COVID-19 , Otolaringologia , Alemanha/epidemiologia , Hospitais Universitários , Humanos , Pandemias , SARS-CoV-2 , Estudantes , Ensino
8.
Laryngorhinootologie ; 99(10): 694-706, 2020 10.
Artigo em Alemão | MEDLINE | ID: mdl-32767296

RESUMO

INTRODUCTION: Since December 2019, the SARS-CoV-2 virus has been rapidly spreading worldwide. In Germany, an exponential increase in the number of infections was registered at the beginning of March 2020 and led to a call of the Ministry of Health to create more capacity for intensive medical treatment in hospitals. The aim of the present study was to determine the effects of the SARS-CoV-2 pandemic on Oto-Rhino-Laryngology (ORL) university hospitals regarding patient care. MATERIALS AND METHODS: An online survey was sent out to all chairmen of the 39 ORL university hospitals in Germany. The answers to the questions referred to the defined period from March 15th to April 15th 2020 and were carried out using the online survey tool "SurveyMonkey". 87 questions focused on general information, health care, and structural effects in the respective institution. RESULTS: All chairmen of the 39 university hospitals in Germany participated in the survey. The collected data prove the considerable impact on organizational, structural and medical aspects of patient care. For example, the surveyed clinics reported a decrease in outpatient cases by 73.8 % to 26.2 ±â€Š14.2 % and in surgical treatments by 65.9 % to 34.1 ±â€Š13.9 %. In contrast, emergency treatment remained unchanged or even increased in 80 % of the facilities and surgical treatment of emergency patients remained unchanged or even increased in more than 90 %. Emergency outpatient and surgical treatment of patients was provided throughout the pandemic in all facilities. In total, about 35 000 outpatients and about 12 000 surgical cases were postponed. As a result of the acute structural changes, the potential danger of falling below current treatment standards was seen in individual areas of patient care. DISCUSSION: The assessment of the impact of the SARS-CoV-2 pandemic is heterogeneous. The majority of the chairmen are critically aware of the risk of falling below current medical treatment standards or guidelines. In the phase of an exponential increase in the number of infections, significant changes in treatment processes had to be accepted for understandable reasons. However, with the currently significantly reduced number of infections, falling below treatment standards and guidelines should not be allowed to remain constant and tolerated. SUMMARY: This study shows a differentiated picture with regard to the effects of the SARS-CoV-2 pandemic on outpatient, inpatient and operative patient care at the ORL university hospitals in Germany and illustrates the importance of these institutions for ensuring patient care during this critical phase.


Assuntos
Infecções por Coronavirus , Otolaringologia , Pandemias , Pneumonia Viral , Síndrome Respiratória Aguda Grave/epidemiologia , Síndrome Respiratória Aguda Grave/terapia , Betacoronavirus , COVID-19 , Alemanha , Hospitais Universitários , Humanos , SARS-CoV-2
9.
Rev Med Chil ; 147(1): 41-46, 2019.
Artigo em Espanhol | MEDLINE | ID: mdl-30848763

RESUMO

BACKGROUND: Pelvic venous insufficiency may cause pelvic congestion syndrome that is characterized by chronic pelvic pain exacerbated by prolonged standing, sexual activity or menstrual cycle. It may be treated by embolizing the dysfunctional pelvic venous drainage and sometimes resecting vulvar, perineal and thigh varices. AIM: To assess the results of embolization of insufficient pelvic or ovarian veins on pelvic congestion syndrome. MATERIAL AND METHODS: Analysis of 17 female patients aged 32 to 53 years, who underwent subjected to a selective coil embolization of insufficient pelvic and/or ovarian veins through the jugular, basilic or cephalic veins. In the preoperative period, all patients had a lower extremity venous duplex pelvic ultrasound examination and some had an abdominal and pelvic CT angiogram. RESULTS: The technical success of the procedure was 100% and no complications were registered. During a 32 month follow up, no patient had symptoms of pelvic venous insufficiency or relapse of vulvar or thigh varices. CONCLUSIONS: Embolization of insufficient pelvic and ovarian veins is a safe and successful procedure for the treatment of pelvic venous insufficiency or vulvar varices.


Assuntos
Embolização Terapêutica/métodos , Ovário/irrigação sanguínea , Dor Pélvica/terapia , Pelve/irrigação sanguínea , Varizes/terapia , Adulto , Dor Crônica , Feminino , Humanos , Pessoa de Meia-Idade , Ovário/diagnóstico por imagem , Dor Pélvica/diagnóstico por imagem , Pelve/diagnóstico por imagem , Flebografia/métodos , Reprodutibilidade dos Testes , Estudos Retrospectivos , Síndrome , Resultado do Tratamento , Varizes/diagnóstico por imagem
10.
Phys Rev Lett ; 121(17): 177202, 2018 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-30411922

RESUMO

The coupled spin-1 chains material NiCl_{2}-4SC(NH_{2})_{2} (DTN) doped with Br impurities is expected to be a perfect candidate for observing many-body localization at high magnetic field: the so-called "Bose glass," a zero-temperature bosonic fluid, compressible, gapless, incoherent, and short-range correlated. Using nuclear magnetic resonance, we critically address the stability of the Bose glass in doped DTN, and find that it hosts a novel disorder-induced ordered state of matter, where many-body physics leads to an unexpected resurgence of quantum coherence emerging from localized impurity states. An experimental phase diagram of this new "order-from-disorder" phase, established from nuclear magnetic resonance T_{1}^{-1} relaxation rate data in the 13±1% Br-doped DTN, is found to be in excellent agreement with the theoretical prediction from large-scale quantum Monte Carlo simulations.

11.
Clin Otolaryngol ; 43(3): 828-834, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29281765

RESUMO

OBJECTIVES: This study aimed to examine the psychosocial health status of adult cochlear implant (CI) users, compared to that of hearing aid (HA) users, hearing-impaired adults without hearing aids and normally hearing adults. DESIGN: Cross-sectional observational study, using both self-reported survey data and a speech-in-noise test. SETTING: Data as collected within the Netherlands Longitudinal Study on Hearing (NL-SH) between September 2011 and June 2016 were used. PARTICIPANTS: Data from 1254 Dutch adults (aged 23-74), selected in a convenience sample design, were included for analyses. MEAN OUTCOME MEASURES: Psychosocial health measures included emotional and social loneliness, anxiety, depression, distress and somatisation. Psychosocial health, hearing status, use of hearing technology and covariates were measured by self-report; hearing ability was assessed through an online digit triplet speech-in-noise test. RESULTS: After adjusting for the degree of hearing impairment, HA users (N = 418) and hearing-impaired adults (N = 247) had significantly worse scores on emotional loneliness than CI users (N = 37). HA users had significantly higher anxiety scores than CI users in some analyses. Non-significant differences were found between normally hearing (N = 552) and CI users for all psychosocial outcomes. CONCLUSIONS: Psychosocial health of CI users is not worse than that of hearing-impaired adults with or without hearing aids. CI users' level of emotional loneliness is even lower than that of their hearing-impaired peers using hearing aids. A possible explanation is that CI patients receive more professional and family support, and guidance along their patient journey than adults who are fitted with hearing aids.


Assuntos
Implantes Cocleares , Emoções , Perda Auditiva/psicologia , Qualidade de Vida , Comportamento Social , Adulto , Idoso , Estudos de Casos e Controles , Estudos de Coortes , Estudos Transversais , Feminino , Nível de Saúde , Perda Auditiva/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Países Baixos , Adulto Jovem
12.
Clin Otolaryngol ; 43(1): 240-248, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28772342

RESUMO

OBJECTIVE: Development of the 'Otology Questionnaire Amsterdam' (OQUA), a patient reported outcome measure (PROM), measuring the severity and impact of ear complaints of patients visiting an ENT surgeon. DESIGN: Multicenter, cross-sectional study. Phase 1: qualitative research. In-depth interviews (N = 16) to identify relevant types of ear complaints and to formulate items. Pilot study of the first and second draft of the OQUA (N = 32, N = 39). Phase 2: quantitative research. Field-testing of the OQUA (N = 352). Item reduction based on inter-item correlation, factor analysis and expert opinion. SETTING: Two secondary and two tertiary ENT clinics. PARTICIPANTS: Patients over the age of sixteen visiting an ENT surgeon with an ear complaint. MAIN OUTCOME MEASURES: Phase 1: meaning units and frequency of selected descriptions. Phase 2: inter-item correlation, factor loading and Cronbach's Alpha (α). RESULTS: Phase 1: eight relevant types of ear complaints were identified: earache, pressure in ear, hearing loss, tinnitus, otorrhoea, itch, dizziness and loss of taste. Phase 2: factor analysis generated a factor 'impact' (α = 0.913). The current version of the OQUA consists of 34 items, covers eight types of ear complaints and consists of two constructs: complaints and impact. CONCLUSION: The OQUA is a generic, otologic PROM designed to evaluate the severity of ear complaints and their impact on patients lives.


Assuntos
Perda Auditiva/diagnóstico , Medidas de Resultados Relatados pelo Paciente , Psicometria/métodos , Inquéritos e Questionários , Zumbido/diagnóstico , Vertigem/diagnóstico , Adolescente , Adulto , Idoso , Estudos Transversais , Feminino , Perda Auditiva/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Países Baixos/epidemiologia , Projetos Piloto , Reprodutibilidade dos Testes , Zumbido/epidemiologia , Vertigem/epidemiologia , Adulto Jovem
13.
Phys Rev Lett ; 118(24): 247201, 2017 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-28665634

RESUMO

We report a ^{51}V nuclear magnetic resonance investigation of the frustrated spin-1/2 chain compound LiCuVO_{4}, performed in pulsed magnetic fields and focused on high-field phases up to 56 T. For the crystal orientations H∥c and H∥b, we find a narrow field region just below the magnetic saturation where the local magnetization remains uniform and homogeneous, while its value is field dependent. This behavior is the first microscopic signature of the spin-nematic state, breaking spin-rotation symmetry without generating any transverse dipolar order, and is consistent with theoretical predictions for the LiCuVO_{4} compound.

14.
Phys Rev Lett ; 118(1): 017001, 2017 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-28106424

RESUMO

We report the NMR observation of a skewed distribution of ^{17}O Knight shifts when a magnetic field quenches superconductivity and induces long-range charge-density-wave (CDW) order in YBa_{2}Cu_{3}O_{y}. This distribution is explained by an inhomogeneous pattern of the local density of states N(E_{F}) arising from quasiparticle scattering off, yet unidentified, defects in the CDW state. We argue that the effect is most likely related to the formation of quasiparticle bound states, as is known to occur, under specific circumstances, in some metals and superconductors (but not in the CDW state, in general, except for very few cases in 1D materials). These observations should provide insight into the microscopic nature of the CDW, especially regarding the reconstructed band structure and the sensitivity to disorder.

15.
Doc Ophthalmol ; 134(2): 129-134, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28224239

RESUMO

PURPOSE: The DTL fibre electrode is commonly used to record the electric potentials elicited by stimulation of the retina. Two positions are commonly used: it is placed either on the cornea along the lower lid or in the conjunctival fornix. The PERG and OPs have previously been examined and compared under both conditions. The aim of this study was to examine the ERG, flicker response and on-off responses with differing electrode positions. METHODS: Before recruitment, all subjects underwent an ophthalmological examination. We enrolled 13 normal control subjects into the study aged 13-64 years, all with a visual acuity of ≥1.0. We recorded scotopic and photopic ERGs, flicker and on-off responses, for both electrode positions. On the first day, one eye had the electrode placed on the cornea along the lower lid and the other eye had it positioned in the conjunctival sac. On a second day, the recordings were repeated with the alternative electrode placements. RESULTS: ERG, on-off and flicker responses were all smaller by between 20 and 25% when the DTL electrode was positioned in the conjunctival sac, compared to when it was positioned on the cornea, as did the scatter in the data points. This indicates that there is no advantage clinically for one or the other placement. CONCLUSIONS: Our results confirm other reports examining the effect of electrode position on electrophysiological potentials. When recording with the DTL electrode, it is important to ensure that it is placed at the same position in repeat recordings or in multicentre trials and that it is stable and does not move during recording.


Assuntos
Eletrofisiologia/métodos , Eletrorretinografia/métodos , Microeletrodos , Retina/fisiologia , Adolescente , Adulto , Estudos de Casos e Controles , Córnea/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estimulação Luminosa/métodos , Acuidade Visual , Adulto Jovem
16.
Phys Rev Lett ; 117(10): 106402, 2016 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-27636483

RESUMO

We present a direct NMR method to determine whether the interactions in a Tomonaga-Luttinger liquid (TLL) state of a spin-1/2 Heisenberg antiferromagnetic ladder are attractive or repulsive. For the strong-leg spin ladder compound (C_{7}H_{10}N)_{2}CuBr_{4} we find that the isothermal magnetic field dependence of the NMR relaxation rate T_{1}^{-1}(H) displays a concave curve between the two critical fields bounding the TLL regime. This is in sharp contrast to the convex curve previously reported for a strong-rung ladder, (C_{5}H_{12}N)_{2}CuBr_{4}. We show that the concavity and the convexity of T_{1}^{-1}(H), which is a fingerprint of spin fluctuations, directly reflect the attractive and repulsive fermionic interactions in the TLL, respectively. The interaction sign is alternatively determined from an indirect method combining bulk magnetization and specific heat data.

17.
Eur J Gynaecol Oncol ; 37(5): 622-626, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-29786998

RESUMO

The aim of reconstruction with expanders is to restore breast shape and volume as close as possible to the contralateral breast and to reconstruct the inframammary fold with adequate ptosis.


Assuntos
Mamoplastia/métodos , Mastectomia/métodos , Feminino , Humanos , Mamoplastia/efeitos adversos
18.
Infect Immun ; 83(7): 2651-60, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25895972

RESUMO

Chlamydia pneumoniae is a Gram-negative bacterium that causes acute or chronic respiratory infections. As obligate intracellular pathogens, chlamydiae efficiently manipulate host cell processes to ensure their intracellular development. Here we focused on the interaction of chlamydiae with the host cell transcription factor activator protein 1 (AP-1) and its consequence on chlamydial development. During Chlamydia pneumoniae infection, the expression and activity of AP-1 family proteins c-Jun, c-Fos, and ATF-2 were regulated in a time- and dose-dependent manner. We observed that the c-Jun protein and its phosphorylation level significantly increased during C. pneumoniae development. Small interfering RNA knockdown of the c-Jun protein in HEp-2 cells reduced the chlamydial load, resulting in smaller inclusions and significantly lower chlamydial recovery. Furthermore, inhibition of the c-Jun-containing AP-1 complexes using tanshinone IIA changed the replicative infection phenotype into a persistent one. Tanshinone IIA-dependent persistence was characterized by smaller, aberrant inclusions, a strong decrease in the chlamydial load, and significantly reduced chlamydial recovery, as well as by the reversibility of the reduced recovery after the removal of tanshinone IIA. Interestingly, not only was tanshinone IIA treatment accompanied by a significant decrease of ATP levels, but fluorescence live cell imaging analysis by two-photon microscopy revealed that tanshinone IIA treatment also resulted in a decreased fluorescence lifetime of protein-bound NAD(P)H inside the chlamydial inclusion, indicating that chlamydial reticulate bodies have decreased metabolic activity. In all, these data demonstrate that the AP-1 transcription factor is involved in C. pneumoniae development, with tanshinone IIA treatment resulting in persistence.


Assuntos
Chlamydophila pneumoniae/crescimento & desenvolvimento , Regulação Bacteriana da Expressão Gênica , Hepatócitos/microbiologia , Hepatócitos/fisiologia , Interações Hospedeiro-Patógeno , Fator de Transcrição AP-1/metabolismo , Transcrição Gênica , Carga Bacteriana , Células Hep G2 , Humanos
19.
Infect Immun ; 83(1): 405-16, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25385797

RESUMO

The exotoxins TcdA and TcdB are the major virulence factors of Clostridium difficile. Circulating neutralizing antitoxin antibodies are protective in C. difficile infection (CDI), as demonstrated, in part, by the protective effects of actoxumab and bezlotoxumab, which bind to and neutralize TcdA and TcdB, respectively. The question of how systemic IgG antibodies neutralize toxins in the gut lumen remains unresolved, although it has been suggested that the Fc receptor FcRn may be involved in active antibody transport across the gut epithelium. In this study, we demonstrated that genetic ablation of FcRn and excess irrelevant human IgG have no impact on actoxumab-bezlotoxumab-mediated protection in murine and hamster models of CDI, suggesting that Fc-dependent transport of antibodies across the gut wall is not required for efficacy. Tissue distribution studies in hamsters suggest, rather, that the transport of antibodies depends on toxin-induced damage to the gut lining. In an in vitro two-dimensional culture system that mimics the architecture of the intestinal mucosal epithelium, toxins on the apical side of epithelial cell monolayers are neutralized by basolateral antibodies, and antibody transport across the cell layer is dramatically increased upon addition of toxin to the apical side. Similar data were obtained with F(ab')2 fragments, which lack an Fc domain, consistent with FcRn-independent paracellular, rather than transcellular, transport of antibodies. Kinetic studies show that initial damage caused by apical toxin is required for efficient neutralization by basolateral antibodies. These data may represent a general mechanism of humoral response-mediated protection against enteric pathogens.


Assuntos
Anticorpos Antibacterianos/imunologia , Anticorpos Neutralizantes/imunologia , Antitoxinas/imunologia , Proteínas de Bactérias/toxicidade , Toxinas Bacterianas/toxicidade , Enterotoxinas/toxicidade , Animais , Anticorpos Antibacterianos/metabolismo , Anticorpos Antibacterianos/uso terapêutico , Anticorpos Neutralizantes/metabolismo , Anticorpos Neutralizantes/uso terapêutico , Antitoxinas/metabolismo , Antitoxinas/uso terapêutico , Proteínas de Bactérias/imunologia , Toxinas Bacterianas/imunologia , Clostridioides difficile/imunologia , Infecções por Clostridium/terapia , Modelos Animais de Doenças , Enterotoxinas/imunologia , Feminino , Antígenos de Histocompatibilidade Classe I , Imunização Passiva , Imunoglobulina G/imunologia , Imunoglobulina G/metabolismo , Imunoglobulina G/uso terapêutico , Masculino , Mesocricetus , Camundongos Endogâmicos C57BL , Camundongos Knockout , Técnicas de Cultura de Órgãos , Receptores Fc/deficiência
20.
Ann Oncol ; 26(9): 1948-1953, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26122726

RESUMO

BACKGROUND: Biosimilars of filgrastim are in widespread clinical use in Europe. This phase III study compares biosimilar filgrastim (EP2006), with the US-licensed reference product, Neupogen(®), in breast cancer patients receiving (neo)adjuvant myelosuppressive chemotherapy (TAC). PATIENTS AND METHODS: A total of 218 patients receiving 5 µg/kg/day filgrastim over six chemotherapy cycles were randomized 1:1:1:1 into four arms. Two arms received only one product (nonalternating), biosimilar or reference, and two arms (alternating) received alternating treatments during each cycle (biosimilar then reference or vice versa). The primary end point was duration of severe neutropenia (DSN) during cycle 1. RESULTS: The baseline characteristics were balanced between the four treatment arms. Noninferiority of biosimilar versus the reference was demonstrated: DSN (days) in cycle 1 was 1.17 ± 1.11 (biosimilar, N = 101) and 1.20 ± 1.02 (reference, N = 103), 97.5% confidence interval lower boundary for the difference was -0.26 days (above the predefined limit of -1 day). No clinically meaningful differences were observed regarding any other efficacy parameter: incidence of febrile neutropenia (FN); hospitalization due to FN; incidence of infections; depth and time of absolute neutrophil count (ANC) nadir and time to ANC recovery during cycle 1 and across all cycles. The pattern and frequency of adverse events were similar across all treatments. CONCLUSION: This study demonstrates that biosimilar and the reference filgrastim are similar with no clinically meaningful differences regarding efficacy and safety in prevention of severe neutropenia. Biosimilar filgrastim could represent an important alternative to the reference product, potentially benefiting public health by increasing access to filgrastim treatment. STUDY NUMBER: NCT01519700.


Assuntos
Medicamentos Biossimilares/uso terapêutico , Filgrastim/análogos & derivados , Filgrastim/uso terapêutico , Neutropenia/prevenção & controle , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Método Duplo-Cego , Feminino , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Humanos , Pessoa de Meia-Idade , Terapia Neoadjuvante , Neutropenia/tratamento farmacológico , Adulto Jovem
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