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1.
Cancers (Basel) ; 13(13)2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34209558

RESUMO

Invasive urothelial bladder cancer (UBC) has high recurrence rates even after radical cystectomy (RC). Exosomes are membrane-bound nanovesicles, which have been shown to contribute to carcinogenesis and metastasis. We previously showed that urinary exosomes display a malignant profile in UBC patients despite the absence of detectable tumour. Here, we investigated exosomes from sampling sites close to or distant from the former tumour, aiming to understand the effect of the tumour on the local milieu. Ten patients scheduled for cystectomy after transurethral bladder resection (TUR-B), without remaining detectable tumour, were included. Exosomes were isolated from tissue explants of both the previous tumour site and distant bladder tissue. Proteins were quantified by mass spectrometry in seven patients. Exosomes from the previous tumour site were enriched in inflammatory but not cancer-related pathways compared to distant tissue. However, the 69 most abundant proteins in tissue-derived exosomes regardless of site, 20 of which were also found in urinary exosomes from our previous study, were enriched for cancer-related metabolic pathways and associated with poor prognosis in an external mRNA dataset. The enrichment of cancer-related pathways in the most abundant proteins, regardless of sampling site, confirms our hypothesis that despite the absence of detectable tumour, the entire bladder releases exosomes that contribute to metastasis and highlights the need for early RC.

2.
World J Urol ; 38(9): 2207-2213, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31760442

RESUMO

PURPOSE: To examine the relationship between the number of tumour draining sentinel nodes (SNs) and pathoanatomical outcomes, in muscle-invasive bladder cancer (MIBC), in patients undergoing neoadjuvant chemotherapy (NAC) and radical cystectomy (RC). MATERIALS AND METHODS: In an ongoing prospective multicenter study, we included 230 patients with suspected urothelial MIBC from ten Swedish urological centers. All underwent TURb and clinical staging. From the cohort, 116 patients with urothelial MIBC; cT2-cT4aN0M0, underwent radical cystectomy (RC) and lymphadenectomy with SN-detection (SNd). 83 patients received cisplatin-based NAC and 33 were NAC-naïve. The number and locations of detected SNs and non-SNs were recorded for each patient. The NAC treated patients were categorized by pathoanatomical outcomes post-RC into three groups: complete responders (CR), stable disease (SD) and progressive disease (PD). Selected covariates with possible impact on SN-yield were tested in uni -and multivariate analyses for NAC-treated patients only. RESULTS: In NAC treated patients, the mean number of SNs was significantly higher in CR patients (3.3) and SD patients (3.6) compared with PD patients (1.4) (p = 0.034). In a linear multivariate regression model, the number of harvested nodes was the only independent variable that affected the number of SNs (p = 0.0004). CONCLUSIONS: The number of tumor-draining SNs in NAC-treated patients was significantly lower in patients with progressive disease.


Assuntos
Quimioterapia Adjuvante , Cistectomia , Linfonodo Sentinela/patologia , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Liso/patologia , Terapia Neoadjuvante , Invasividade Neoplásica , Estadiamento de Neoplasias , Estudos Prospectivos , Resultado do Tratamento
3.
ACS Nano ; 13(3): 3500-3511, 2019 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-30735350

RESUMO

We measure the coherent nonlinear response of excitons in a single layer of molybdenum disulfide embedded in hexagonal boron nitride, forming a h-BN/MoS2/ h-BN heterostructure. Using four-wave mixing microscopy and imaging, we correlate the exciton inhomogeneous broadening with the homogeneous one and population lifetime. We find that the exciton dynamics is governed by microscopic disorder on top of the ideal crystal properties. Analyzing the exciton ultrafast density dynamics using amplitude and phase of the response, we investigate the relaxation pathways of the resonantly driven exciton population. The surface protection via encapsulation provides stable monolayer samples with low disorder, avoiding surface contaminations and the resulting exciton broadening and modifications of the dynamics. We identify areas localized to a few microns where the optical response is totally dominated by homogeneous broadening. Across the sample of tens of micrometers, weak inhomogeneous broadening and strain effects are observed, attributed to the remaining interaction with the h-BN and imperfections in the encapsulation process.

4.
PLoS One ; 13(7): e0200079, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29966014

RESUMO

The immune system plays a significant role in urothelial bladder cancer (UBC) progression, with CD8+ T cells being capable to directly kill tumor cells using perforin and granzymes. However, tumors avoid immune recognition by escape mechanisms. In this study, we aim to demonstrate tumor immune escape mechanisms that suppress CD8+ T cells cytotoxicity. 42 patients diagnosed with UBC were recruited. CD8+ T cells from peripheral blood (PB), sentinel nodes (SN), and tumor were analyzed in steady state and in vitro-stimulated conditions by flow cytometry, RT-qPCR, and ELISA. Mass spectrometry (MS) was used for identification of proteins from UBC cell line culture supernatants. Perforin was surprisingly found to be low in CD8+ T cells from SN, marked by 1.8-fold decrease of PRF1 expression, with maintained expression of granzyme B. The majority of perforin-deficient CD8+ T cells are effector memory T (TEM) cells with exhausted Tc2 cell phenotype, judged by the presence of PD-1 and GATA-3. Consequently, perforin-deficient CD8+ T cells from SN are low in T-bet expression. Supernatant from muscle invasive UBC induces perforin deficiency, a mechanism identified by MS where ICAM-1 and TGFß2 signaling were causatively validated to decrease perforin expression in vitro. Thus, we demonstrate a novel tumor escape suppressing perforin expression in CD8+ T cells mediated by ICAM-1 and TGFß2, which can be targeted in combination for cancer immunotherapy.


Assuntos
Linfócitos T CD8-Positivos/metabolismo , Regulação Neoplásica da Expressão Gênica , Molécula 1 de Adesão Intercelular/metabolismo , Perforina/metabolismo , Transdução de Sinais , Fator de Crescimento Transformador beta2/metabolismo , Neoplasias da Bexiga Urinária/metabolismo , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Perforina/genética , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/patologia
5.
Eur Urol ; 74(6): 688-692, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30025882

RESUMO

Evidence indicates that neoadjuvant chemotherapy (NAC) may promote antitumour immune responses by activating T cells. The tumour-draining sentinel node (SN) is a key site to study tumour-specific T cell activation, being the primary immunological barrier against the tumour. In this prospective study, we set out to elucidate the effects of NAC on T cell subsets in the SNs of patients with muscle-invasive urothelial bladder cancer. We found that CD8+ effector T (Teff) cell exhaustion was reduced after NAC treatment, while cytotoxicity was increased. Additionally, in complete responders (CR patients), these cells were functionally committed effectors, as displayed by epigenetic analysis. In CD4+ Teffs, NAC treatment was associated with increased clonal expansion of tumour-specific SN-derived cells, as demonstrated by a specific cell reactivity assay. In contrast, we observed an attenuating effect of NAC on regulatory T cells (Tregs) with a dose-dependent decrease in Treg frequency and reduced effector molecule expression in the remaining Tregs. In addition, multicolour flow cytometry analysis revealed that CR patients had higher Teff to activated Treg ratio, promoting antitumoural T cell activation. These results suggest that NAC reinforces the antitumour immune response by activating the effector arm of the T cell compartment and diminishing the influence of suppressive Tregs. PATIENT SUMMARY: In this report, we analysed the effect of chemotherapy on immune cell subsets of 40 patients with advanced bladder cancer. We found that chemotherapy has a positive effect on immune effector T cells, whereas an opposite, diminishing effect was observed for immune-suppressive regulatory T cells. We conclude that chemotherapy reinforces the antitumour immune response in bladder cancer patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linfócitos do Interstício Tumoral/efeitos dos fármacos , Terapia Neoadjuvante , Subpopulações de Linfócitos T/efeitos dos fármacos , Neoplasias da Bexiga Urinária/tratamento farmacológico , Bexiga Urinária/efeitos dos fármacos , Urotélio/efeitos dos fármacos , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Quimioterapia Adjuvante , Feminino , Humanos , Ativação Linfocitária/efeitos dos fármacos , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/patologia , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante/efeitos adversos , Estudos Prospectivos , Suécia , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/patologia , Fatores de Tempo , Resultado do Tratamento , Evasão Tumoral/efeitos dos fármacos , Bexiga Urinária/imunologia , Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/imunologia , Neoplasias da Bexiga Urinária/patologia , Urotélio/imunologia , Urotélio/patologia
6.
Nano Lett ; 16(9): 5333-9, 2016 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-27517124

RESUMO

By implementing four-wave mixing (FWM) microspectroscopy, we measure coherence and population dynamics of the exciton transitions in monolayers of MoSe2. We reveal their dephasing times T2 and radiative lifetime T1 in a subpicosecond (ps) range, approaching T2 = 2T1 and thus indicating radiatively limited dephasing at a temperature of 6 K. We elucidate the dephasing mechanisms by varying the temperature and by probing various locations on the flake exhibiting a different local disorder. At the nanosecond range, we observe the residual FWM produced by the incoherent excitons, which initially disperse toward the dark states but then relax back to the optically active states within the light cone. By introducing polarization-resolved excitation, we infer intervalley exciton dynamics, revealing an initial polarization degree of around 30%, constant during the initial subpicosecond decay, followed by the depolarization on a picosecond time scale. The FWM hyperspectral imaging reveals the doped and undoped areas of the sample, allowing us to investigate the neutral exciton, the charged one, or both transitions at the same time. In the latter, we observe the exciton-trion beating in the coherence evolution indicating their coherent coupling.

7.
ACS Photonics ; 3(12): 2461-2466, 2016 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-28713845

RESUMO

Optimized light-matter coupling in semiconductor nanostructures is a key to understand their optical properties and can be enabled by advanced fabrication techniques. Using in situ electron beam lithography combined with a low-temperature cathodoluminescence imaging, we deterministically fabricate microlenses above selected InAs quantum dots (QDs), achieving their efficient coupling to the external light field. This enables performing four-wave mixing microspectroscopy of single QD excitons, revealing the exciton population and coherence dynamics. We infer the temperature dependence of the dephasing in order to address the impact of phonons on the decoherence of confined excitons. The loss of the coherence over the first picoseconds is associated with the emission of a phonon wave packet, also governing the phonon background in photoluminescence (PL) spectra. Using theory based on the independent boson model, we consistently explain the initial coherence decay, the zero-phonon line fraction, and the line shape of the phonon-assisted PL using realistic quantum dot geometries.

8.
Pharmacol Rep ; 66(6): 1077-82, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25443738

RESUMO

BACKGROUND: The aim of this study was to verify whether or not an increased prevalence of excessive daytime sleepiness (EDS) or EEG abnormalities is observed in patients with schizophrenia spectrum disorders (SSD), and to compare the effects of second generation antipsychotics (SGA) on patients' daytime sleepiness level and EEG recordings. METHODS: EEG recordings and self-reports of EDS, assessed with Epworth (ESS) and Stanford (SSS) Sleepiness Scales, were compared between 244 patients with SSD and 82 patients with anxiety, personality or behavioral disorders (non-psychotic disorders, NPD). To examine the effects of various SGA, patients treated in monotherapy with aripiprazole, olanzapine, clozapine, risperidone and sertindole were compared. RESULTS: A higher prevalence of abnormal EEG recordings was observed in SSD patients. No significant differences in average daytime sleepiness were found between patients with SSD and NPD; however, patients with SSD had longer sleep duration. Aripiprazole treatment was associated with significantly smaller and less frequent EEG abnormalities than treatment with any other SGA, while treatment with clozapine and olanzapine was related to an increased prevalence of severe EEG abnormalities. Patients with SSD treated with SGA in monotherapy were less sleepy than unmedicated patients with NPD. CONCLUSIONS: Although antipsychotics may have profound effects on EEG patients with schizophrenia do not have higher daytime sleepiness than patients with anxiety/personality disorders. Patients with schizophrenia may compensate sedative effects of antipsychotic treatment with sleep duration prolongation and report even less sleepiness than non-psychotic patients.


Assuntos
Antipsicóticos/efeitos adversos , Distúrbios do Sono por Sonolência Excessiva/induzido quimicamente , Eletroencefalografia , Transtornos Mentais/tratamento farmacológico , Antipsicóticos/uso terapêutico , Distúrbios do Sono por Sonolência Excessiva/epidemiologia , Humanos , Transtornos Mentais/fisiopatologia , Prevalência , Esquizofrenia/tratamento farmacológico , Índice de Gravidade de Doença
9.
ACS Nano ; 8(10): 9970-8, 2014 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-25181393

RESUMO

We present a micropillar cavity where nondesired radial emission is inhibited. The photonic confinement in such a structure is improved by implementation of an additional concentric radial-distributed Bragg reflector. Such a reflector increases the reflectivity in all directions perpendicular to the micropillar axis from a typical value of 15-31% to above 98%. An inhibition of the spontaneous emission of off-resonant excitonic states of quantum dots embedded in the microcavity is revealed by time-resolved experiments. It proves a decreased density of photonic states related to unwanted radial leakage of photons out of the micropillar. For on-resonance conditions, we find that the dot emission rate is increased, evidencing the Purcell enhancement of spontaneous emission. The proposed design can increase the efficiency of single-photon sources and bring to micropillar cavities the functionalities based on lengthened decay times.

10.
Pharmacol Rep ; 65(3): 614-23, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23950583

RESUMO

BACKGROUND: Sleep disorders are highly prevalent among patients with Parkinson's disease (PD). Chronic medication with L-dopa may be one of the factors that contributes to poor sleep quality. The aim of this study was to assess the effects of long term use of L-dopa on objective and subjective measures of sleep quality in PD patients. METHODS: Twenty-seven PD patients (mean age 62.5 ± 8.6 years, mean disease duration 7.3 ± 5.9 years, 11 females) underwent nocturnal polysomnography. Their sleep was rated subjectively using the Parkinson's disease sleep scale (PDSS), and their disease severity was assessed using the unified Parkinson's disease severity scale (UPDRS) standard questionnaire. Doses of L-dopa and other medications were correlated with parameters of sleep quality. The polysomnographic recordings were compared with those from 24 age- and gender-matched normal controls. RESULTS: The patients showed decreased total sleep time (TST) and sleep efficiency (SE), prolonged sleep onset and REM sleep latency and wake after sleep onset (WASO). Parts I-III of the UPDRS scores correlated with TST, SE and WASO but not with PDSS scores. L-dopa dosage and part IV of the UPDRS correlated with PDSS scores but not with polysomnographic parameters. CONCLUSIONS: Higher doses of chronically administered L-dopa correlated with lower sleep quality according to the subjective measures but not according to the polysomnographic parameters, which were related to the severity of PD symptoms. The low sleep quality according to the subjective measurements may result from complications of therapy at high doses of L-dopa.


Assuntos
Levodopa/efeitos adversos , Doença de Parkinson/complicações , Transtornos do Sono-Vigília/induzido quimicamente , Transtornos do Sono-Vigília/etiologia , Sono/efeitos dos fármacos , Feminino , Humanos , Levodopa/uso terapêutico , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/tratamento farmacológico , Polissonografia/métodos , Índice de Gravidade de Doença , Inquéritos e Questionários
12.
Nanotechnology ; 22(28): 285204, 2011 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-21654032

RESUMO

Micropillars of different diameters have been prepared by focused ion beam milling out of a planar ZnTe-based cavity. The monolithic epitaxial structure, deposited on a GaAs substrate, contains CdTe quantum dots embedded in a ZnTe λ-cavity delimited by two distributed Bragg reflectors (DBRs). The high refractive index material of the DBR structure is ZnTe, while for the low index material a short-period triple MgTe/ZnTe/MgSe superlattice is used. The CdTe quantum dots are formed by a novel Zn-induced formation process and are investigated by scanning transmission electron microscopy. Micro-photoluminescence measurements show discrete optical modes for the pillars, in good agreement with calculations based on a vectorial transfer matrix method. The measured quality factor reaches a value of 3100.

13.
Przegl Lek ; 67(9): 726-8, 2010.
Artigo em Polonês | MEDLINE | ID: mdl-21387813

RESUMO

BACKGROUND: Narcolepsy is a chronic hypersomnia of central origin, linked with dysfunction of hypocretin-containing neurons, localized in the lateral hypothalamus. Main symptoms of narcolepsy include excessive daytime sleepiness, cataplexy, hypnagogic hallucinations and sleep paralysis. Establishing the proper diagnosis is very important, because of the negative impact of narcolepsy on patients' functioning in social-life and the possibility of improvement of quality of life with adequate treatment. AIM OF THE STUDY: Present review describes clinical characteristics of narcolepsy, usefulness of neurophysiological tests in differential diagnosis of narcolepsy and assessing the efficacy of the treatment, as well as the application of novel biological methods in diagnosis of narcolepsy. METHODS AND RESULTS: According to diagnostic criteria of ICSD-2 the diagnosis of narcolepsy is based on the clinical features and diagnostic examinations and tests. Among them neurophysiological procedures, such as polysomnography (PSG) and Multiple Sleep Latency Test (MSLT) are still recommended as most useful in differential diagnosis of narcolepsy and other hypersomnias. In recent decades novel biochemical and genetic tools have been developed as diagnostic measures in narcolepsy, including the levels of hypocretin in cerebral spinal fluid and HLA DQB1*0602 typing. These both biological markers are strongly associated with the occurrence of cataplexy, therefore do not present considerable diagnostic value in narcolepsy without cataplexy. CONCLUSIONS: Neurophysiological procedures (MSLT) and biological markers are necessary in the diagnosis of narcolepsy with cataplexy and hypersomnia without cataplexy. Neurophysiological procedures are useful in monitoring of the treatment of hypersomnia also.


Assuntos
Narcolepsia/diagnóstico , Biomarcadores/líquido cefalorraquidiano , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/líquido cefalorraquidiano , Monitorização Fisiológica , Narcolepsia/líquido cefalorraquidiano , Exame Neurológico , Neuropeptídeos/líquido cefalorraquidiano , Orexinas , Polissonografia
14.
Przegl Lek ; 67(9): 732-5, 2010.
Artigo em Polonês | MEDLINE | ID: mdl-21387815

RESUMO

BACKGROUND: Event related potentials (ERPs) originate predominantly from cortical structures in response to information processing. In contrast to evoked potentials of short latency (<100 ms), long latency cognitive ERPs are not directly related to the physical characteristics of the stimulus, but rather to the information and meaning that the stimulus has for the investigated person. AIM: The aim of this review article was to present selected research questions in psychiatry that can be addressed with ERP studies. As examples we used studies performed in patients with schizophrenia and posttraumatic stress disorder (PTSD). METHODS: ERPs can be recorded during well established cognitive tests in psychiatry: go-no go, n-back, continuous performance test (CPT), Wisconsin card sorting test, Stroop test, verbal learning test and many others. Several ERP components are used as endophenotypes in genetic psychiatric research. CONCLUSIONS: ERPs can be also useful in clinic related questions: identification of subject at high-risk of psychosis, assessment of attention deficits or selective attention problems in anxiety disorders, evaluation of early response to psychopharmacological treatment and efficacy of psychotherapeutic interventions.


Assuntos
Potenciais Evocados , Esquizofrenia/diagnóstico , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Humanos , Esquizofrenia/fisiopatologia , Transtornos de Estresse Pós-Traumáticos/tratamento farmacológico , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Resultado do Tratamento
15.
Neurol Neurochir Pol ; 39(4): 263-275, 2005.
Artigo em Polonês | MEDLINE | ID: mdl-16096942

RESUMO

BACKGROUND AND PURPOSE: Spinocerebellar ataxias type 1 (SCA1) and type 2 (SCA2) belong to neurodegenerative disorders of autosomal dominant inheritance, genetically and clinically heterogeneous, caused by the expansion of CAG trinucleotides. Trunk and limb ataxia, dysarthria, dysphagia, gaze palsy, sensory and motor axonal neuropathy are the dominant features in both entities. The aim of the study was to evaluate the differences between genotype and phenotype based on clinical and electrophysiological assessment of the visual, auditory pathways, and EEG alterations in comparison with the cerebellar and brain atrophy in MRI. MATERIAL AND METHODS: 44 patients with SCA1 and 24 cases with SCA2 confirmed molecularly were examined neurologically and using the International Cooperative Ataxia Rating Scale (ICARS). A correlation of clinical symptoms and signs, and CAG repeat numbers with EEG, visual (VEP) and brainstem auditory (BAEP) evoked potentials, and MRI alterations were evaluated. RESULTS: A statistically significant negative correlation between the age of disease onset and number of CAG repeats in both types of SCA was found. Examined patients with SCA2 were younger, with longer disease duration and more pronounced cerebellar and brain atrophy in MRI. We found a significant correlation between ICARS and CAG repeats in this group. The dysphagia, pyramidal tract involvement and depressive reaction were significantly frequent in SCA1 patients. However in SCA2 patients, the peripheral nerve damage and extrapyramidal signs were more prominent. The amplitude of P100 visual evoked potentials was significantly lower in SCA1 patients and negatively correlated with CAG repeats. CONCLUSIONS: These results provide further evidence for the phenotypic differences of genetically defined SCA1 and SCA2 patients, expressed by more frequent involvement of the pyramidal tract and depression reaction in SCA1, in contrast to peripheral nerve involvement and extrapyramidal signs in the clinical feature of SCA2 phenotype. Furthermore, atrophy of the brain and cerebellum revealed in MRI was more pronounced than electrophysiological functional alterations, especially in SCA2. The decreased amplitude of P100 VEP in SCA1 patients was the only electrophysiological parameter differentiating between both groups of patients.


Assuntos
Eletroencefalografia , Imageamento por Ressonância Magnética , Ataxias Espinocerebelares , Expansão das Repetições de Trinucleotídeos/genética , Adulto , Fatores Etários , Idoso , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/epidemiologia , Depressão/diagnóstico , Depressão/epidemiologia , Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Potenciais Evocados Visuais/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Índice de Gravidade de Doença , Ataxias Espinocerebelares/genética , Ataxias Espinocerebelares/patologia , Ataxias Espinocerebelares/fisiopatologia , Inquéritos e Questionários
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