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1.
Nature ; 586(7827): 47-51, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32999484

RESUMO

Radiation sensors based on the heating effect of absorbed radiation are typically simple to operate and flexible in terms of input frequency, so they are widely used in gas detection1, security2, terahertz imaging3, astrophysical observations4 and medical applications5. Several important applications are currently emerging from quantum technology and especially from electrical circuits that behave quantum mechanically, that is, circuit quantum electrodynamics6. This field has given rise to single-photon microwave detectors7-9 and a quantum computer that is superior to classical supercomputers for certain tasks10. Thermal sensors hold potential for enhancing such devices because they do not add quantum noise and they are smaller, simpler and consume about six orders of magnitude less power than the frequently used travelling-wave parametric amplifiers11. However, despite great progress in the speed12 and noise levels13 of thermal sensors, no bolometer has previously met the threshold for circuit quantum electrodynamics, which lies at a time constant of a few hundred nanoseconds and a simultaneous energy resolution of the order of 10h gigahertz (where h is the Planck constant). Here we experimentally demonstrate a bolometer that operates at this threshold, with a noise-equivalent power of 30 zeptowatts per square-root hertz, comparable to the lowest value reported so far13, at a thermal time constant two orders of magnitude shorter, at 500 nanoseconds. Both of these values are measured directly on the same device, giving an accurate estimation of 30h gigahertz for the calorimetric energy resolution. These improvements stem from the use of a graphene monolayer with extremely low specific heat14 as the active material. The minimum observed time constant of 200 nanoseconds is well below the dephasing times of roughly 100 microseconds reported for superconducting qubits15 and matches the timescales of currently used readout schemes16,17, thus enabling circuit quantum electrodynamics applications for bolometers.

2.
Anim Cogn ; 26(3): 861-883, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36494587

RESUMO

The nature of the representation guiding spatial navigation has been investigated extensively; however, most of this work has used behavioral tasks that involved learning the location of food reward or an escape platform. In contrast, relatively few studies have focused on the spatial representation of a home base, a ubiquitous feature of open-field behavior, and its ability to be encoded relative to environmental cues. The current set of experiments investigated acquisition and retention of the location of home base establishment. In general, proximal cues anchored the position of the home base during acquisition sessions across all four experiments. Although mice established a home base during retention sessions, previous experience did not influence its position during retention sessions. These observations demonstrate that stimulus control of home base position depends on access to proximal cues. Further work is needed to determine the extent that home base establishment may provide a framework to encode goal-directed spatial behaviors.


Assuntos
Sinais (Psicologia) , Navegação Espacial , Camundongos , Animais , Comportamento Exploratório
3.
Phys Rev Lett ; 129(2): 021801, 2022 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-35867467

RESUMO

We report the first results of a search for leptophobic dark matter (DM) from the Coherent-CAPTAIN-Mills (CCM) liquid argon (LAr) detector. An engineering run with 120 photomultiplier tubes (PMTs) and 17.9×10^{20} protons on target (POT) was performed in fall 2019 to study the characteristics of the CCM detector. The operation of this 10-ton detector was strictly light based with a threshold of 50 keV and used coherent elastic scattering off argon nuclei to detect DM. Despite only 1.5 months of accumulated luminosity, contaminated LAr, and nonoptimized shielding, CCM's first engineering run has already achieved sensitivity to previously unexplored parameter space of light dark matter models with a baryonic vector portal. With an expected background of 115 005 events, we observe 115 005+16.5 events which is compatible with background expectations. For a benchmark mediator-to-DM mass ratio of m_{V_{B}}/m_{χ}=2.1, DM masses within the range 9 MeV≲m_{χ}≲50 MeV are excluded at 90% C. L. in the leptophobic model after applying the Feldman-Cousins test statistic. CCM's upgraded run with 200 PMTs, filtered LAr, improved shielding, and 10 times more POT will be able to exclude the remaining thermal relic density parameter space of this model, as well as probe new parameter space of other leptophobic DM models.

4.
Phys Rev Lett ; 117(3): 030802, 2016 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-27472107

RESUMO

We experimentally investigate and utilize electrothermal feedback in a microwave nanobolometer based on a normal-metal (Au_{x}Pd_{1-x}) nanowire with proximity-induced superconductivity. The feedback couples the temperature and the electrical degrees of freedom in the nanowire, which both absorbs the incoming microwave radiation, and transduces the temperature change into a radio-frequency electrical signal. We tune the feedback in situ and access both positive and negative feedback regimes with rich nonlinear dynamics. In particular, strong positive feedback leads to the emergence of two metastable electron temperature states in the millikelvin range. We use these states for efficient threshold detection of coherent 8.4 GHz microwave pulses containing approximately 200 photons on average, corresponding to 1.1×10^{-21} J≈7.0 meV of energy.

5.
BMC Infect Dis ; 16: 475, 2016 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-27600394

RESUMO

BACKGROUND: Data containing notified cases of disease are often compromised by incomplete or partial information related to individual cases. In an effort to enhance the value of information from enteric disease notifications in New Zealand, this study explored the use of Bayesian and Multiple Imputation (MI) models to fill risk factor data gaps. As a test case, overseas travel as a risk factor for infection with campylobacteriosis has been examined. METHODS: Two methods, namely Bayesian Specification (BAS) and Multiple Imputation (MI), were compared regarding predictive performance for various levels of artificially induced missingness of overseas travel status in campylobacteriosis notification data. Predictive performance of the models was assessed through the Brier Score, the Area Under the ROC Curve and the Percent Bias of regression coefficients. Finally, the best model was selected and applied to predict missing overseas travel status of campylobacteriosis notifications. RESULTS: While no difference was observed in the predictive performance of the BAS and MI methods at a lower rate of missingness (<10 %), but the BAS approach performed better than MI at a higher rate of missingness (50 %, 65 %, 80 %). The estimated proportion (95 % Credibility Intervals) of travel related cases was greatest in highly urban District Health Boards (DHBs) in Counties Manukau, Auckland and Waitemata, at 0.37 (0.12, 0.57), 0.33 (0.13, 0.55) and 0.28 (0.10, 0.49), whereas the lowest proportion was estimated for more rural West Coast, Northland and Tairawhiti DHBs at 0.02 (0.01, 0.05), 0.03 (0.01, 0.08) and 0.04 (0.01, 0.06), respectively. The national rate of travel related campylobacteriosis cases was estimated at 0.16 (0.02, 0.48). CONCLUSION: The use of BAS offers a flexible approach to data augmentation particularly when the missing rate is very high and when the Missing At Random (MAR) assumption holds. High rates of travel associated cases in urban regions of New Zealand predicted by this approach are plausible given the high rate of travel in these regions, including destinations with higher risk of infection. The added advantage of using a Bayesian approach is that the model's prediction can be improved whenever new information becomes available.


Assuntos
Infecções por Campylobacter/epidemiologia , Notificação de Doenças , Modelos Teóricos , Viagem , Teorema de Bayes , Infecções por Campylobacter/prevenção & controle , Infecções por Campylobacter/transmissão , Humanos , Nova Zelândia/epidemiologia , Fatores de Risco , População Rural
6.
Nano Lett ; 15(5): 2965-73, 2015 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-25927475

RESUMO

Bulk 1T-TaSe2 exhibits unusually high charge density wave (CDW) transition temperatures of 600 and 473 K below which the material exists in the incommensurate (I-CDW) and the commensurate (C-CDW) charge-density-wave phases, respectively. The (13)(1/2) × (13)(1/2) C-CDW reconstruction of the lattice coincides with new Raman peaks resulting from zone-folding of phonon modes from middle regions of the original Brillouin zone back to Γ. The C-CDW transition temperatures as a function of film thickness are determined from the evolution of these new Raman peaks, and they are found to decrease from 473 to 413 K as the film thicknesses decrease from 150 to 35 nm. A comparison of the Raman data with ab initio calculations of both the normal and C-CDW phases gives a consistent picture of the zone-folding of the phonon modes following lattice reconstruction. The Raman peak at ∼154 cm(-1) originates from the zone-folded phonons in the C-CDW phase. In the I-CDW phase, the loss of translational symmetry coincides with a strong suppression and broadening of the Raman peaks. The observed change in the C-CDW transition temperature is consistent with total energy calculations of bulk and monolayer 1T-TaSe2.

7.
Br J Cancer ; 113(12): 1677-86, 2015 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-26645238

RESUMO

BACKGROUND: Foxp3+ regulatory T cells (Tregs) play a vital role in preventing autoimmunity, but also suppress antitumour immune responses. Tumour infiltration by Tregs has strong prognostic significance in colorectal cancer, and accumulating evidence suggests that chemotherapy and radiotherapy efficacy has an immune-mediated component. Whether Tregs play an inhibitory role in chemoradiotherapy (CRT) response in rectal cancer remains unknown. METHODS: Foxp3+, CD3+, CD4+, CD8+ and IL-17+ cell density in post-CRT surgical samples from 128 patients with rectal cancer was assessed by immunohistochemistry. The relationship between T-cell subset densities and clinical outcome (tumour regression and survival) was evaluated. RESULTS: Stromal Foxp3+ cell density was strongly associated with tumour regression grade (P=0.0006). A low stromal Foxp3+ cell density was observed in 84% of patients who had a pathologic complete response (pCR) compared with 41% of patients who did not (OR: 7.56, P=0.0005; OR: 5.27, P=0.006 after adjustment for presurgery clinical factors). Low stromal Foxp3+ cell density was also associated with improved recurrence-free survival (HR: 0.46, P=0.03), although not independent of tumour regression grade. CONCLUSIONS: Regulatory T cells in the tumour microenvironment may inhibit response to neoadjuvant CRT and may represent a therapeutic target in rectal cancer.


Assuntos
Fatores de Transcrição Forkhead/imunologia , Neoplasias Retais/tratamento farmacológico , Neoplasias Retais/radioterapia , Linfócitos T Reguladores/imunologia , Idoso , Quimioterapia Adjuvante , Terapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radioterapia Adjuvante , Resultado do Tratamento
8.
Ann Oncol ; 26(12): 2483-90, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26386124

RESUMO

BACKGROUND: Data from murine models suggest that CD40 activation may synergize with cytotoxic chemotherapy. We aimed to determine the maximum tolerated dose (MTD) and toxicity profile and to explore immunological biomarkers of the CD40-activating antibody CP-870,893 with cisplatin and pemetrexed in patients with malignant pleural mesothelioma (MPM). PATIENTS AND METHODS: Eligible patients had confirmed MPM, ECOG performance status 0-1, and measurable disease. Patients received cisplatin 75 mg/m(2) and pemetrexed 500 mg/m(2) on day 1 and CP-870,893 on day 8 of a 21-day cycle for maximum 6 cycles with up to 6 subsequent cycles single-agent CP-870,893. Immune cell subset changes were examined weekly by flow cytometry. RESULTS: Fifteen patients were treated at three dose levels. The MTD of CP-870,893 was 0.15 mg/kg, and was exceeded at 0.2 mg/kg with one grade 4 splenic infarction and one grade 3 confusion and hyponatraemia. Cytokine release syndrome (CRS) occurred in most patients (80%) following CP-870,893. Haematological toxicities were consistent with cisplatin and pemetrexed chemotherapy. Six partial responses (40%) and 9 stable disease (53%) as best response were observed. The median overall survival was 16.5 months; the median progression-free survival was 6.3 months. Three patients survived beyond 30 months. CD19+ B cells decreased over 6 cycles of chemoimmunotherapy (P < 0.001) with a concomitant increase in the proportion of CD27+ memory B cells (P < 0.001) and activated CD86+CD27+ memory B cells (P < 0.001), as an immunopharmacodynamic marker of CD40 activation. CONCLUSIONS: CP-870,893 with cisplatin and pemetrexed is safe and tolerable at 0.15 mg/kg, although most patients experience CRS. While objective response rates are similar to chemotherapy alone, three patients achieved long-term survival. AUSTRALIA NEW ZEALAND CLINICAL TRIALS REGISTRY NUMBER: ACTRN12609000294257.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Antígenos CD40/metabolismo , Cisplatino/administração & dosagem , Neoplasias Pulmonares/tratamento farmacológico , Mesotelioma/tratamento farmacológico , Pemetrexede/administração & dosagem , Neoplasias Pleurais/tratamento farmacológico , Adulto , Idoso , Anticorpos Monoclonais Humanizados , Antígenos CD40/agonistas , Estudos de Coortes , Feminino , Seguimentos , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/metabolismo , Masculino , Mesotelioma/diagnóstico , Mesotelioma/metabolismo , Mesotelioma Maligno , Pessoa de Meia-Idade , Neoplasias Pleurais/diagnóstico , Neoplasias Pleurais/metabolismo , Estudos Prospectivos
9.
J Vet Pharmacol Ther ; 37(4): 348-53, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24330064

RESUMO

Ondansetron is a 5-HT3 receptor antagonist that is an effective anti-emetic in cats. The purpose of this study was to evaluate the pharmacokinetics of ondansetron in healthy cats. Six cats with normal complete blood count, serum biochemistry, and urinalysis received 2 mg oral (mean 0.43 mg/kg), subcutaneous (mean 0.4 mg/kg), and intravenous (mean 0.4 mg/kg) ondansetron in a cross-over manner with a 5-day wash out. Serum was collected prior to, and at 0.25, 0.5, 1, 2, 4, 8, 12, 18, and 24 h after administration of ondansetron. Ondansetron concentrations were measured using liquid chromatography coupled to tandem mass spectrometry. Noncompartmental pharmacokinetic modeling and dose interval modeling were performed. Repeated measures anova was used to compare parameters between administration routes. Bioavailability of ondansetron was 32% (oral) and 75% (subcutaneous). Calculated elimination half-life of ondansetron was 1.84 ± 0.58 h (intravenous), 1.18 ± 0.27 h (oral) and 3.17 ± 0.53 h (subcutaneous). The calculated elimination half-life of subcutaneous ondansetron was significantly longer (P < 0.05) than oral or intravenous administration. Subcutaneous administration of ondansetron to healthy cats is more bioavailable and results in a more prolonged exposure than oral administration. This information will aid management of emesis in feline patients.


Assuntos
Antieméticos/farmacocinética , Gatos/metabolismo , Ondansetron/farmacocinética , Administração Oral , Animais , Antieméticos/administração & dosagem , Área Sob a Curva , Disponibilidade Biológica , Gatos/sangue , Meia-Vida , Injeções Intravenosas , Injeções Subcutâneas , Ondansetron/administração & dosagem
10.
Behav Brain Res ; 469: 115062, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38768689

RESUMO

To conserve sequential behavior in relation to the topographic challenges of space, it is proposed that humans and nonhuman animals can organize behavior using different scaling principles. To deal with increases in linear distance, isochrony suggest that there is a corresponding increase in speed, whereas to deal with changes in curvature, speed is adjusted according to a power function. The present study investigates whether these principles provide a framework for describing the organization of mouse behavior in a variety of standard experimental tasks. The structure of movement was examined in ambulation during open field exploration; manipulation in a string-pulling task, in which a string is advanced hand over hand to retrieve food; and rung-walking, in which the limbs successively step from rung to rung on a horizontal ladder. Both principles were found to be conserved in the organization of mouse behavior across scales of movement. These principles provide novel measures of the temporal and geometric features of movement in the mouse and insights into how the temporal and geometric features of movement are conserved within different species.


Assuntos
Comportamento Exploratório , Animais , Camundongos , Masculino , Comportamento Exploratório/fisiologia , Camundongos Endogâmicos C57BL , Movimento/fisiologia , Atividade Motora/fisiologia , Locomoção/fisiologia , Comportamento Animal/fisiologia , Caminhada/fisiologia
11.
Br J Cancer ; 109(7): 1813-20, 2013 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-23982605

RESUMO

BACKGROUND: Recent studies proposed neutrophil-to-lymphocyte ratio (NLR) as a prognostic biomarker in malignant pleural mesothelioma (MPM). We examined baseline prognostic variables including NLR and the EORTC and CALGB models as predictors of overall survival (OS) in MPM. METHODS: In this retrospective study, 274 consecutive eligible, newly presenting patients with MPM were included. Of these, 159 received chemotherapy, 10 had tri-modality therapy, 2 underwent surgery only and 103 received supportive care alone. Univariate analyses and multivariate Cox models were calculated for OS. RESULTS: In univariate analysis, poor prognostic factors were: age ≥65 years, nonepithelioid histology, stage III-IV, poor performance status (PS), weight loss, chest pain, low haemoglobin and high platelet count. A baseline NLR≥ 5 did not predict worse OS (hazard ratio (HR) 1.25; P=0.122). On multivariate analysis, age, histology, PS, weight loss, chest pain and platelet count remained significant. The EORTC and CALGB prognostic groups were validated as predictive for OS (HR 1.62; P<0.001 and HR 1.65; P<0.001, respectively). CONCLUSION: Our findings validate standard prognostic variables and the existing EORTC and CALGB models, but not NLR, at initial diagnosis of MPM. In guiding patient management at diagnosis, it is important to consider multiple baseline variables that jointly predict survival.


Assuntos
Biomarcadores Tumorais , Neoplasias Pulmonares/mortalidade , Linfócitos/citologia , Mesotelioma/mortalidade , Neutrófilos/citologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Contagem de Leucócitos , Neoplasias Pulmonares/tratamento farmacológico , Contagem de Linfócitos , Masculino , Mesotelioma/tratamento farmacológico , Mesotelioma Maligno , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida
12.
Euro Surveill ; 18(40)2013 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-24128700

RESUMO

Differentiation between travel-related and domestic cases of infectious disease is important in managing risk. Incubation periods of cases from several outbreaks of campylobacteriosis in Canada, Europe, and the United States with defined exposure time of less than 24 hours were collated to provide information on the incubation period distribution. This distribution was consistent across the varied outbreaks considered, with 84% (702/832) of cases having an incubation period of four days or less and 1% having an incubation period of eight days or more. The incubation period distribution was incorporated into a model for the number of travel-related cases presenting with symptom onset at given dates after return to their country of residence. Using New Zealand notification data between 2006 and 2010 for cases who had undertaken foreign travel within 10 days prior to symptom onset, we found that 29.6% (67/227 cases; 95% confidence interval (CI): 28.3­30.8%) of these cases were likely to have been domestic cases. When cases with symptom onset prior to arrival were included, the probable domestic cases represented 11.8% (67/571; 95% CI: 11.2­12.3%). Consideration of incubation time distributions and consistent collection of travel start/end dates with symptom onset dates would assist attribution of cases to foreign travel.


Assuntos
Infecções por Campylobacter/epidemiologia , Surtos de Doenças , Período de Incubação de Doenças Infecciosas , Viagem , Canadá/epidemiologia , Intervalos de Confiança , Notificação de Doenças , Europa (Continente)/epidemiologia , Humanos , Incidência , Nova Zelândia/epidemiologia , Estados Unidos/epidemiologia
13.
Nat Genet ; 26(4): 484-9, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11101851

RESUMO

Notch receptors are involved in cell-fate determination in organisms as diverse as flies, frogs and humans. In Drosophila melanogaster , loss-of-function mutations of Notch produce a 'neurogenic' phenotype in which cells destined to become epidermis switch fate and differentiate to neural cells. Upon ligand activation, the intracellular domain of Notch (ICN) translocates to the nucleus, and interacts directly with the DNA-binding protein Suppressor of hairless (Su(H)) in flies, or recombination signal binding protein Jkappa (RBP-Jkappa) in mammals, to activate gene transcription. But the precise mechanisms of Notch-induced gene expression are not completely understood. The gene mastermind has been identified in multiple genetic screens for modifiers of Notch mutations in Drosophila. Here we clone MAML1, a human homologue of the Drosophila gene Mastermind, and show that it encodes a protein of 130 kD localizing to nuclear bodies. MAML1 binds to the ankyrin repeat domain of all four mammalian NOTCH receptors, forms a DNA-binding complex with ICN and RBP-Jkappa, and amplifies NOTCH-induced transcription of HES1. These studies provide a molecular mechanism to explain the genetic links between mastermind and Notch in Drosophila and indicate that MAML1 functions as a transcriptional co-activator for NOTCH signalling.


Assuntos
Proteínas de Ligação a DNA , Proteínas de Drosophila , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo , Transativadores/genética , Transativadores/metabolismo , Células 3T3 , Animais , Células COS , Drosophila/genética , Genes de Insetos , Humanos , Camundongos , Dados de Sequência Molecular , Mutação , Receptores Notch , Especificidade da Espécie , Fatores de Transcrição , Transfecção
14.
Rev Sci Instrum ; 94(5)2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-37249411

RESUMO

We report calibrated microwave transmission and reflection measurements of a qubit sample holder at millikelvin temperatures. The methodology we present extends our previous work on one-port cryogenic short-open-load (SOL) calibration to a two-port SOLT measurement by implementing an unknown thru (T) standard. We report the resulting calibrated transmission and reflection at millikelvin temperatures through a printed circuit board that is installed into the sample holder. Finally, we consider a cascade of components at the end of a qubit drive line that includes (1) a cryogenic attenuator, (2) a coaxial cable, and (3) a qubit sample holder. Using experimentally determined parameters for return losses for all three components, we calculate the negligible state-preparation error in the frequency band of 5-7 GHz due to control pulse distortions arising from reflection at the coaxial launches. Taken together, our results highlight the utility of calibrated cryogenic scattering parameter measurements for the validation of qubit packaging and the wiring in its immediate vicinity.

15.
Rev Sci Instrum ; 94(5)2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-37227193

RESUMO

Recently, great progress has been made in the field of ultrasensitive microwave detectors, reaching even the threshold for utilization in circuit quantum electrodynamics. However, cryogenic sensors lack the compatibility with broad-band metrologically traceable power absorption measurements at ultralow powers, which restricts their range of applications. Here, we demonstrate such measurements using an ultralow-noise nanobolometer, which we extend by an additional direct-current (dc) heater input. The tracing of the absorbed power relies on comparing the response of the bolometer between radio frequency and dc-heating powers traced to the Josephson voltage and quantum Hall resistance. To illustrate this technique, we demonstrate two different methods of dc-substitution to calibrate the power that is delivered to the base temperature stage of a dilution refrigerator using our in situ power sensor. As an example, we demonstrate the ability to accurately measure the attenuation of a coaxial input line between the frequencies of 50 MHz and 7 GHz with an uncertainty down to 0.1 dB at a typical input power of -114 dBm.

16.
Br J Cancer ; 107(7): 1107-15, 2012 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-22910319

RESUMO

BACKGROUND: There is increasing interest in combining chemotherapy with immunotherapy. However, the effects of chemotherapy on the human immune system are largely unknown. METHODS: Longitudinal changes in peripheral T-cell subsets in 40 patients with malignant mesothelioma (MM) or advanced non-small cell lung cancer (NSCLC) receiving platinum-based chemotherapy were assessed by flow cytometry and evaluated for associations with clinical outcome. RESULTS: Proliferating T cells of all subsets were almost entirely depleted at day 8 following chemotherapy, but rapidly recovered above baseline levels. Regulatory T cells (Treg) were most profoundly depleted at this time point. A greater increase in CD8(+) T-cell proliferation following one treatment cycle was associated with improved overall survival in univariate (hazard ratio (HR)=0.40; P<0.05) and multivariate (HR=0.17; P<0.01) analyses. A greater increase in the ratio of CD8(+) T cell to Treg proliferation was also predictive of better prognosis. CONCLUSION: Chemotherapy potentially provides a favourable environment for the development of anti-tumour immunity through transient Treg depletion and regeneration of the T-cell pool. Change in CD8(+) T-cell proliferation after one cycle of chemotherapy may represent a useful prognostic indicator in patients with MM and NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/imunologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/imunologia , Subpopulações de Linfócitos T/efeitos dos fármacos , Subpopulações de Linfócitos T/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/imunologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Proliferação de Células/efeitos dos fármacos , Estudos de Coortes , Feminino , Humanos , Neoplasias Pulmonares/patologia , Masculino , Mesotelioma/tratamento farmacológico , Mesotelioma/imunologia , Mesotelioma/patologia , Pessoa de Meia-Idade , Compostos Organoplatínicos/administração & dosagem , Resultado do Tratamento
17.
Clin Case Rep ; 10(3): e05583, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35340637

RESUMO

Warm autoimmune hemolytic anemia (AIHA) is a hematologic disorder with an incidence of 1-3 per 105 individuals/year. Patients with systemic lupus erythematosus (SLE) develop AIHA in 3% of adult cases and 14% of pediatric cases. We report a case of AIHA refractory to multiple lines of treatment in a patient with SLE, who eventually responded to a proteasome inhibitor-based combination. A patient with systemic lupus erythematous was diagnosed with symptomatic autoimmune hemolytic anemia. The patient was refractory to multiple lines of treatment including prednisone, intravenous immune globulin, methylprednisolone, rituximab, cyclophosphamide, mycophenolate mofetil, and splenectomy. She eventually had a beneficial response to a proteasome inhibitor-based combination with bortezomib plus mycophenolate mofetil. The treatment of refractory autoimmune hemolytic anemia can be challenging. Patients with AIHA refractory to primary or secondary treatments must resort to receiving novel therapeutic modalities including combinations targeting plasma cell, T- and B-cell proliferation.

18.
Behav Processes ; 201: 104713, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35901935

RESUMO

Age-related changes in spatial and temporal processing have been documented across a range of species. Rodent studies typically investigate differences in performance between adult and senescent animals; however, progressive loss of neurons in the hippocampus and cortex has been observed to occur as early as after adolescence. Therefore, the current study evaluated the effects of age in three- and ten-month-old female rats on the organization of movement in open field and food protection behaviors, two tasks that have previously dissociated hippocampal and cortical pathology. Age-related differences were observed in general measures of locomotion, spatial orientation, and attentional processing. The results of the current study are consistent with age-related changes in the processing of spatial information and motivation that occur earlier in life than previously anticipated. These observations establish a foundation for future studies evaluating interventions that influence these age-related differences in performance.


Assuntos
Orientação Espacial , Percepção Espacial , Animais , Feminino , Hipocampo/fisiologia , Locomoção/fisiologia , Neurônios/fisiologia , Ratos , Percepção Espacial/fisiologia
19.
Behav Brain Res ; 416: 113577, 2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-34506841

RESUMO

Astronauts undertaking deep space travel will receive chronic exposure to the mixed spectrum of particles that comprise Galactic Cosmic Radiation (GCR). Exposure to the different charged particles of varied fluence and energy that characterize GCR may impact neural systems that support performance on mission critical tasks. Indeed, growing evidence derived from years of terrestrial-based simulations of the space radiation environment using rodents has indicated that a variety of exposure scenarios can result in significant and long-lasting decrements to CNS functionality. Many of the behavioral tasks used to quantify radiation effects on the CNS depend on neural systems that support maintaining spatial orientation and organization of rodent open field behavior. The current study examined the effects of acute or chronic exposure to simulated GCR on the organization of open field behavior under conditions with varied access to environmental cues in male and female C57BL/6 J mice. In general, groups exhibited similar organization of open field behavior under dark and light conditions. Two exceptions were noted: the acute exposure group exhibited significantly slower and more circuitous homeward progressions relative to the chronic group under light conditions. These results demonstrate the potential of open field behavior organization to discriminate between the effects of select GCR exposure paradigms.


Assuntos
Radiação Cósmica/efeitos adversos , Sinais (Psicologia) , Comportamento Exploratório/fisiologia , Orientação Espacial/fisiologia , Exposição à Radiação/efeitos adversos , Animais , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Voo Espacial
20.
Phys Rev Lett ; 107(6): 063202, 2011 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-21902321

RESUMO

We report on a measurement of craters in thin dielectric films formed by Xe(Q+) (26 ≤ Q ≤ 44) projectiles. Tunnel junction devices with ion-irradiated barriers were used to amplify the effect of charge-dependent cratering through the exponential dependence of tunneling conductance on barrier thickness. Electrical conductance of a crater σ(c)(Q) increased by 4 orders of magnitude (7.9 × 10(-4) µS to 6.1 µS) as Q increased, corresponding to crater depths ranging from 2 to 11 Å. By employing a heated spike model, we determine that the energy required to produce the craters spans from 8 to 25 keV over the investigated charge states. Considering energy from preequilibrium nuclear and electronic stopping as well as neutralization, we find that at least (27 ± 2)% of available projectile neutralization energy is deposited into the thin film during impact.

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