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1.
Lung Cancer ; 187: 107427, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38043395

RESUMO

AIM: Osimertinib is a third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) approved for patients with EGFR mutated non-small cell lung cancer as first-line treatment. However, treatment resistance inevitably emerges and may present as oligo-progressive disease (OPD) or systemic progressive disease (SPD). The incidence of OPD on first-line osimertinib is unknown. METHODS: We retrospectively analyzed patients who received first-line osimertinib at 13 Swiss centers. The rate of OPD (PD in ≤ 5 lesions) and treatment outcomes were analyzed. RESULTS: The median age of the 148 patients was 68.2 years (range. 38.0-93.3). There were 62 % females, 83 % with a PS ≤ 1, 59 % never smokers, 57 % of patients with an EGFR exon 19 deletion and 37 % with EGFR p.L858R exon 21. 77 % experienced OPD. Median overall survival (OS) was 51.6 months (95 % CI, 38.4-65.0). Median progression-free survival (PFS) was 19.2 (95 % CI, 14.3-23.5) and 8.7 (95 % CI, 2.8-15.6) months for patients with common and uncommon EGFR mutations. Patients with OPD compared to SPD had a significantly longer time to treatment failure and longer OS of (22.9 vs. 10.8 months, p < 0.001 and 51.6 vs. 26.4 months, p = 0.004, respectively). The most common organ sites of PD were lung (62 %), brain (30 %), lymph nodes (30 %), bone (27 %) and pleura (27 %). Twenty-six patients (45 %) with OPD received local ablative treatment (LAT). The OS of OPD patients with LAT was 60.0 (95 % CI, 51.6-NA) vs. 51.4 (95 % CI 38.4-65.3) months (p = 0.43) without LAT. CONCLUSION: The rate of OPD of patients receiving first line osimertinib was 77 %. Patients with OPD had a significantly better OS compared to patients with SPD (51.6 vs. 26.4 months). Patients with OPD receiving LAT had the longest median OS (60.0 months).


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Feminino , Humanos , Masculino , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Estudos de Coortes , Estudos Retrospectivos , Suíça , Inibidores de Proteínas Quinases/farmacologia , Compostos de Anilina/uso terapêutico , Receptores ErbB/genética , Mutação
2.
Neural Netw ; 166: 634-644, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37604074

RESUMO

Among several approaches to tackle the problem of energy consumption in modern computing systems, two solutions are currently investigated: one consists of artificial neural networks (ANNs) based on photonic technologies, the other is a different paradigm compared to ANNs and it is based on random networks of non-linear nanoscale junctions resulting from the assembling of nanoparticles or nanowires as substrates for neuromorphic computing. These networks show the presence of emergent complexity and collective phenomena in analogy with biological neural networks characterized by self-organization, redundancy, and non-linearity. Starting from this background, we propose and formalize a generalization of the perceptron model to describe a classification device based on a network of interacting units where the input weights are non-linearly dependent. We show that this model, called "receptron", provides substantial advantages compared to the perceptron as, for example, the solution of non-linearly separable Boolean functions with a single device. The receptron model is used as a starting point for the implementation of an all-optical device that exploits the non-linearity of optical speckle fields produced by a solid scatterer. By encoding these speckle fields we generated a large variety of target Boolean functions. We demonstrate that by properly setting the model parameters, different classes of functions with different multiplicity can be solved efficiently. The optical implementation of the receptron scheme opens the way for the fabrication of a completely new class of optical devices for neuromorphic data processing based on a very simple hardware.


Assuntos
Generalização Psicológica , Nanofios , Redes Neurais de Computação , Fótons
3.
J Synchrotron Radiat ; 30(Pt 1): 217-226, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36601940

RESUMO

FOCUS (Fast Monte CarlO approach to Coherence of Undulator Sources) is a new GPU-based simulation code to compute the transverse coherence of undulator radiation from ultra-relativistic electrons. The core structure of the code, which is written in the language C++ accelerated with CUDA, combines an analytical description of the emitted electric fields and massively parallel computations on GPUs. The combination is rigorously justified by a statistical description of synchrotron radiation based on a Fourier optics approach. FOCUS is validated by direct comparison with multi-electron Synchrotron Radiation Workshop (SRW) simulations, evidencing a reduction in computation times by up to five orders of magnitude on a consumer laptop. FOCUS is then applied to systematically study the transverse coherence in typical third- and fourth-generation facilities, highlighting peculiar features of undulator sources close to the diffraction limit. FOCUS is aimed at fast evaluation of the transverse coherence of undulator radiation as a function of the electron beam parameters, to support and help prepare more advanced and detailed numerical simulations with traditional codes like SRW.

4.
Front Endocrinol (Lausanne) ; 13: 1030398, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36483002

RESUMO

Background and Objectives: Endocrine complications have been described in patients affected by RASopathies but no systematic assessment has been reported. In this study, we investigate the prevalence of endocrine disorders in a consecutive unselected cohort of patients with RASopathies. Study Design: 72 patients with a genetically confirmed RASopathy (Noonan syndrome [NS], N=53; 29 LEOPARD syndrome [LS], N=2; cardiofaciocutaneous syndrome [CFCS], N=14; subjects showing co-occurring pathogenic variants in PTPN11 and NF1, N=3) and an age- and sex-matched healthy controls were included in the study. Endocrine system involvement was investigated by assessing the thyroid function, pubertal development, auxological parameters, adrenal function and bone metabolism. Results: Short stature was detected in 40% and 64% of the NS and CFCS subcohorts, respectively. Patients showed lower Z-scores at DXA than controls (p<0.05) when considering the entire case load and both NS and CFCS groups. Vitamin D and Calcitonin levels were significantly lower (p< 0.01), Parathormone levels significantly higher (p<0.05) in patients compared to the control group (p<0.05). Patients with lower BMD showed reduced physical activity and joint pain. Finally, anti-TPO antibody levels were significantly higher in patients than in controls when considering the entire case load and both NS and CFCS groups. Conclusions: The collected data demonstrate a high prevalence of thyroid autoimmunity, confirming an increased risk to develop autoimmune disorders both in NS and CFCS. Reduced BMD, probably associated to reduced physical activity and inflammatory cytokines, also occurs. These findings are expected to have implications for the follow-up and prevention of osteopenia/osteoporosis in both NS and CFCS.


Assuntos
Sistema Endócrino , Pesquisa , Humanos
5.
Orphanet J Rare Dis ; 16(1): 410, 2021 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-34600590

RESUMO

BACKGROUND: Abnormalities of the immune system are rarely reported in patients affected by RASopathies. Aim of the current study was to investigate the prevalence of immune system dysfunction in a cohort of patients affected by RASopathies. STUDY DESIGN: A group of 69 patients was enrolled: 60 at the Federico II University, Naples, 7 at University Magna Graecia of Catanzaro, 2 at "Scuola Medica Salernitana", Salerno. An age- and sex-matched control group was also enrolled. Autoimmune disorders were investigated according to international consensus criteria. Immune framework was also evaluated by immunoglobulin levels, CD3, CD4, CD8, CD19, CD56 lymphocyte subpopulations, autoantibodies levels and panel of inflammatory molecules, in both patients and controls. RESULTS: Frequent upper respiratory tract infections were recorded in 2 patients; pneumonia, psoriasis and alopecia in single patients. Low IgA levels were detected in 8/44 patients (18.18%), low CD8 T cells in 13/35 patients (37.14%). Anti-tg and anti-TPO antibodies were detected in 3/24 patients (12.5%), anti r-TSH in 2 cases (8.33%), all in euthyroidism. Serum IgA and CD8 levels were significantly lower in patients than in controls (p 0.00685; p 0.000656 respectively). All tested patients showed increased inflammatory molecules compared to controls. These findings may anticipate the detection of overt autoimmune disease. CONCLUSIONS: Patients affected by RASopathies are at risk to develop autoimmune disorders. Routine screening for autoimmunity is recommended in patients with RASopathy.


Assuntos
Doenças Autoimunes , Imunidade Celular , Antígenos CD19 , Autoimunidade , Humanos
6.
Opt Express ; 29(10): 14412-14424, 2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-33985165

RESUMO

We describe an innovative data transmission scheme exploiting optical vortices to multiplex and demultiplex independent data channels in a standard asynchronous laser link. We report extensive results of the proof of concept of the method, successfully used to transmit two parallel ASCII strings, demultiplexed and decoded in the far field of the radiation beam. A phase locked two arms interferometer is proved to be effective even accessing a small portion of the beam only. Results prove the robustness and reliability of the method to perform dense-code free space transmissions over long distances even in presence of wavefront distortions. Applications and the extension to a larger number of parallel channels are discussed.

7.
Appl Opt ; 59(17): 5258-5264, 2020 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-32543547

RESUMO

We show a method to measure the topological charge of orbital angular momentum radiation in single-shot by exploiting the intrinsic local curvature of the helicoidal wavefront. The method is based on oriented Hartmann cells in a suitable detection scheme. We show experimental results and propose a Shack-Hartmann configuration with sectored photodiodes to improve resolution and detection time. The method can be applied for telecommunication applications in the far field of the radiation beam and more in general to measure the topological charge from a small portion of the radiation wavefront.

8.
Ital J Pediatr ; 46(1): 65, 2020 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-32430001

RESUMO

BACKGROUND: As the quality and quantity of patient-centered care may be perceived differently by recipients and independent observers, assessment of humanization of pediatric care remains an elusive issue. Herein we aim to analyze differences between the degrees of verified existing vs. perceived humanization issues of a pediatric ward. Furthermore, we examine whether there is concurrence between the degrees of humanization perceived by users (parents/visitors) vs. staff members. METHODS: The study was conducted in the pediatric wards of seven medical centers of the Campania region (Italy) categorized as general (n = 4), children's (n = 1), and university (n = 2) hospitals. The degree of existing humanization was assessed by a multidisciplinary focus group for each hospital through a pediatric care-oriented checklist specifically developed to individuate the most critical areas (i.e., those with scores < 2.5). The degree of perceived humanization was assessed through four indicators: well-being, social aspects, safety and security, and health promotion. RESULTS: The focus groups showed that critical areas common to all centers were mainly concerned with welfare, mediation, translation, and interpretation services. Specific critical issues were care and organizational processes oriented to the respect and specificity of the person and care of the relationship with the patient. Perceived humanization questionnaires revealed a lack of recreational facilities and mediation and translation services. As for specific features investigated by both tools, it was found that mediation and interpretation services were lacking in all facilities while patient perceptions and observer ratings for space, comfort, and orientation concurred only in the general hospital evaluations. CONCLUSIONS: Future humanization interventions to ensure child- and family-friendly hospital care call for careful preliminary assessments, tailored to each pediatric ward category, which should consider possible differences between perceived and verified characteristics.


Assuntos
Atitude do Pessoal de Saúde , Serviços de Saúde da Criança/organização & administração , Pais/psicologia , Assistência Centrada no Paciente/organização & administração , Pediatria , Adulto , Criança , Grupos Focais , Humanos , Itália
9.
Opt Express ; 27(13): 17550-17560, 2019 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-31252712

RESUMO

We describe a method for effectively distinguishing the radiation endowed with optical angular momentum, also known as optical vortex, from ordinary light. We show that by detecting the inversion of the transverse intrinsic curvature sign (ITICS) an optical vortex can be locally recognized. The method is effective under conditions of huge importance for the exploitation of optical vortices, such as the far field of the source and access to a small fraction of the wavefront only. The validity of the method has been verified with table-top experiments with visible light, and the results show that a measurement performed over a transverse distance smaller than 4% of the beam diameter distinguishes a vortex from a Gaussian beam with a significance of 93.4%. New perspectives are considered for the characterization of vortices, with potential impact on the detection of extra-terrestrial radiation as well as on broadcast communication techniques.

10.
Oral Oncol ; 87: 104-110, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30527224

RESUMO

BACKGROUND: Until recently, no second-line treatment for recurrent and/or metastatic head and neck squamous cell cancer (r/mHNSCC) was able to improve overall survival (OS). Nivolumab has become a promising treatment for r/mHNSCC. The CheckMate-141 trial showed that nivolumab improves OS compared to investigator's choice (IC) (cetuximab, methotrexate, docetaxel). Treatment with immune checkpoint inhibitors is however expensive. The aim of this analysis was to assess the cost-effectiveness of nivolumab as second-line treatment for r/mHNSCC in Switzerland. METHODS: Based on the CheckMate-141 trial, we constructed a Markov model comparing nivolumab to IC, including follow-up data up to 24 months. We assessed costs for treatments from the perspective of the Swiss health system with a 60 months' time horizon. PD-L1 and p16 testing were considered in scenarios. Incremental cost-effectiveness ratios (ICER) were compared to an informal willingness-to-pay of CHF (Swiss Francs) 100,000 per QALY gained. RESULTS: For the base case we estimated an incremental effectiveness of 0.35 QALYs and incremental costs of CHF 35,562 with nivolumab, resulting in an ICER of CHF 102,957 per QALY gained. Most influential drivers for the ICER were the price of nivolumab and the progressive disease state utility weights. In 45.5% of probabilistic sensitivity analysis simulations nivolumab was estimated below 100,000 CHF/QALY. Reducing the price of nivolumab according to a consented payback by 4.75%, resulted in an ICER of CHF 98,325/QALY gained. CONCLUSIONS: At current prices nivolumab has an ICER of around CHF 100,000 per QALY gained in the second line treatment of r/mHNSCC patients in Switzerland.


Assuntos
Custos de Medicamentos , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Nivolumabe/uso terapêutico , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Análise Custo-Benefício , Seguimentos , Neoplasias de Cabeça e Pescoço/economia , Humanos , Cadeias de Markov , Modelos Econômicos , Recidiva Local de Neoplasia/economia , Nivolumabe/economia , Qualidade de Vida , Anos de Vida Ajustados por Qualidade de Vida , Carcinoma de Células Escamosas de Cabeça e Pescoço/economia , Suíça
11.
Cytopathology ; 28(4): 273-279, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28217943

RESUMO

BACKGROUND: Fine needle cytology (FNC) of a parathyroid neoplasia (PN) is reliable, but needs to be confirmed by Parathormone (PTH) and Thyroglobulin (TG) immunoassay on needle washing or by immunocytochemistry (ICC) evaluation. The differentiation between parathyroid adenoma (PA), atypical adenoma (PAA) and carcinoma (PC) is difficult on histology or even impossible on FNC. The aim of this study was to evaluate possible cytological criteria to classify FNC-PN further. METHODS: Twenty-three FNC samples of PN and parathyroid cysts were rather then have been reviewed. The series includes 18 PNs, 4 cysts and 1 Thyr3B (histologically diagnosed as PA). Cytological features were: cellularity, patterns (follicular, solid or papillary), clear, oncocytic, isolated cells, nuclear atypia, cytoplasmic inclusions, nucleoli and mitoses. Data were compared with the histological controls. RESULTS: Seventeen PNs, 2 cysts and 1 Thyr3B FNC samples were histologically diagnosed as PA (16), PAA (2) and PC (2). Two cysts and 1 PN were not confirmed histologically. Cytological features and incidences were: high cellularity (1 PA, 1 PAA, 2 PCs), follicular (8 PAs, 1 PAA), solid (5 PAs, 1 PC), papillary pattern (1PA, 1 PAA, 1 PC), clear cells (4 PAs, 1 PAA, 2 PCs), oncocytic cells (6 PAs, 1 PAA, 2 PCs), isolated cells (5 PAs, 2 PAAs, 2 PCs), nuclear atypia (2 PAs, 1 PAA, 2 PCs), cytoplasmic inclusions (4 PAs, 2 PCs), nucleoli (2 PCs) and mitoses (2 PCs). CONCLUSION: Evident nucleoli and mitoses may suggest the differentiation between PA and PC. However, further investigations are required to confirm these preliminary observations.


Assuntos
Glândulas Paratireoides/patologia , Neoplasias das Paratireoides/diagnóstico , Neoplasias das Paratireoides/cirurgia , Biópsia por Agulha Fina , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias das Paratireoides/patologia
12.
Rev Sci Instrum ; 87(12): 126104, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28040961

RESUMO

We developed a broad-spectrum light source specifically designed to reproduce the temporal behavior of the optical pulses emitted by scintillators for X-ray detection. Nanosecond-to-millisecond pulses are generated through a fast circuit driving Light Emitting Diodes (LEDs) and are endowed with the peculiar time features of the most employed scintillators by means of a dedicated pulse shaping stage. We implement the light source for the optical modeling of the single-shot X-ray coherence measurements with near-field speckles generated by the scattering from colloidal suspensions (heterodyne near field speckle method). Moreover, we derive a rigorous scaling law that quantitatively relates visible and X-ray signal-to-noise ratios.

14.
Br J Cancer ; 113(5): 716-21, 2015 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-26313663

RESUMO

BACKGROUND: Gastro-oesophageal adenocarcinomas rarely metastasize to the central nervous system (CNS). The role of the human epidermal growth factor receptor 2 (HER2) in patients with these cancers and CNS involvement is presently unknown. PATIENTS AND METHODS: A multicentre registry was established to collect data from patients with gastro-oesophageal adenocarcinomas and CNS involvement both retrospectively and prospectively. Inclusion in the study required a predefined clinical data set, a central neuro-radiological or histopathological confirmation of metastatic CNS involvement and central assessment of HER2 by immunohistochemistry (IHC) and in situ hybridisation (ISH). In addition, expression of E-cadherin and DNA mismatch repair (MMR) proteins were assessed by IHC. RESULTS: One hundred patients fulfilled the inclusion criteria. The population's median age was 59 years (interquartile range: 54-68), of which 85 (85%) were male. Twenty-five patients were of Asian and 75 of Caucasian origin. HER2 status was positive in 36% (95% CI: 26.6-46.2) of cases. Median time from initial diagnosis to the development of brain metastases (BMets) or leptomeningeal carcinomatosis (LC) was 9.9 months (95% CI: 8.5-15.0). Median overall survival from diagnosis was 16.9 months (95% CI: 14.0-20.7) and was not related to the HER2 status. E-cadherin loss was observed in 9% of cases and loss of expression in at least one DNA MMR proteins in 6%. CONCLUSIONS: The proportion of a positive HER2 status in patients with gastro-oesophageal adenocarcinoma and CNS involvement was higher than expected. The impact of anti-HER2 therapies should be studied prospectively.


Assuntos
Adenocarcinoma/metabolismo , Neoplasias Encefálicas/metabolismo , Neoplasias Esofágicas/metabolismo , Receptor ErbB-2/metabolismo , Neoplasias Gástricas/metabolismo , Adenocarcinoma/mortalidade , Adenocarcinoma/secundário , Idoso , Antígenos CD , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/secundário , Caderinas/metabolismo , Reparo do DNA , Neoplasias Esofágicas/mortalidade , Neoplasias Esofágicas/patologia , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/patologia
15.
Sci Rep ; 5: 10977, 2015 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-26077863

RESUMO

Using electron spectroscopy, we have investigated nanoplasma formation from noble gas clusters exposed to high-intensity hard-x-ray pulses at ~5 keV. Our experiment was carried out at the SPring-8 Angstrom Compact free electron LAser (SACLA) facility in Japan. Dedicated theoretical simulations were performed with the molecular dynamics tool XMDYN. We found that in this unprecedented wavelength regime nanoplasma formation is a highly indirect process. In the argon clusters investigated, nanoplasma is mainly formed through secondary electron cascading initiated by slow Auger electrons. Energy is distributed within the sample entirely through Auger processes and secondary electron cascading following photoabsorption, as in the hard x-ray regime there is no direct energy transfer from the field to the plasma. This plasma formation mechanism is specific to the hard-x-ray regime and may, thus, also be important for XFEL-based molecular imaging studies. In xenon clusters, photo- and Auger electrons contribute more significantly to the nanoplasma formation. Good agreement between experiment and simulations validates our modelling approach. This has wide-ranging implications for our ability to quantitatively predict the behavior of complex molecular systems irradiated by high-intensity hard x-rays.

16.
Lung Cancer ; 87(1): 85-7, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25466451

RESUMO

We present the case of a patient with rapidly accelerated fibrosarcoma gene F (BRAF) mutated adenocarcinoma of the lung, responding to BRAF inhibitor dabrafenib after progressing on vemurafenib followed by docetaxel. The present case illustrates the potential benefit of successful rechallenge with a BRAF inhibitor, a well known phenomenon observed in other oncogenic driven molecular subtypes of non-small cell lung cancer (NSCLC) such as epidermal growth factor receptor mutation. Rechallenge with a BRAF inhibitor in BRAF mutated NSCLC should be considered, particularly in the absence of alternative therpateutic options.


Assuntos
Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/genética , Carcinoma Broncogênico/tratamento farmacológico , Carcinoma Broncogênico/genética , Imidazóis/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Mutação , Oximas/uso terapêutico , Proteínas Proto-Oncogênicas B-raf/genética , Adenocarcinoma/diagnóstico , Antineoplásicos/uso terapêutico , Carcinoma Broncogênico/diagnóstico , Análise Mutacional de DNA , Progressão da Doença , Resistencia a Medicamentos Antineoplásicos , Humanos , Indóis/uso terapêutico , Neoplasias Pulmonares/diagnóstico , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Tomografia por Emissão de Pósitrons , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Retratamento , Sulfonamidas/uso terapêutico , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Vemurafenib
17.
Opt Express ; 23(26): 32888-96, 2015 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-26831956

RESUMO

We exploit the speckle field generated by scattering from a colloidal suspension to access both spatial and temporal coherence properties of broadband radiation. By applying the Wiener-Khinchine theorem to the retrieved temporal coherence function, information about the emission spectrum of the source is obtained in good agreement with the results of a grating spectrometer. Experiments have been performed with visible light. We prove more generally that our approach can be considered as a tool for modeling a variety of cases. Here we discuss how to apply such diagnostics to broad-spectrum betatron radiation produced in the laser-driven wakefield accelerator under development at SPARC LAB facility in Frascati.

18.
Curr Med Chem ; 21(14): 1569-82, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-23992304

RESUMO

Intrinsic and acquired drug resistance of tumor cells still causes the failure of treatment regimens in advanced human cancers. It may be driven by intrinsic tumor cells features, or may also arise from micro environmental influences. Hypoxia is a microenvironment feature associated with the aggressiveness and metastasizing ability of human solid cancers. Hypoxic cancer cells overexpress Carbonic Anhydrase IX (CA IX). CA IX ensures a favorable tumor intracellular pH, while contributing to stromal acidosis, which facilitates tumor invasion and metastasis. The overexpression of CA IX is considered an epiphenomenon of the presence of hypoxic, aggressive tumor cells. Recently, a relationship between CA IX overexpression and the cancer stem cells (CSCs) population has been hypothesized. CSCs are strictly regulated by tumor hypoxia and drive a major non-mutational mechanism of cancer drug-resistance. We reviewed the current data concerning the role of CA IX overexpression in human malignancies, extending such information to the expression of the stem cells markers CD44 and nestin in solid cancers, to explore their relationship with the biological behavior of tumors. CA IX is heavily expressed in advanced tumors. A positive trend of correlation between CA IX overexpression, tumor stage/grade and poor outcome emerged. Moreover, stromal CA IX expression was associated with adverse events occurrence, maybe signaling the direct action of CA IX in directing the mesenchymal changes that favor tumor invasion; in addition, membranous/cytoplasmic co-overexpression of CA IX and stem cells markers were found in several aggressive tumors. This suggests that CA IX targeting could indirectly deplete CSCs and counteract resistance of solid cancers in the clinical setting.


Assuntos
Anidrases Carbônicas/metabolismo , Neoplasias/enzimologia , Hipóxia Celular , Resistencia a Medicamentos Antineoplásicos , Humanos , Imuno-Histoquímica , Neoplasias/patologia , Células-Tronco Neoplásicas/enzimologia
19.
Phys Rev Lett ; 111(7): 073002, 2013 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-23992061

RESUMO

When exposed to ultraintense x-radiation sources such as free electron lasers (FELs) the innermost electronic shell can efficiently be emptied, creating a transient hollow atom or molecule. Understanding the femtosecond dynamics of such systems is fundamental to achieving atomic resolution in flash diffraction imaging of noncrystallized complex biological samples. We demonstrate the capacity of a correlation method called "partial covariance mapping" to probe the electron dynamics of neon atoms exposed to intense 8 fs pulses of 1062 eV photons. A complete picture of ionization processes competing in hollow atom formation and decay is visualized with unprecedented ease and the map reveals hitherto unobserved nonlinear sequences of photoionization and Auger events. The technique is particularly well suited to the high counting rate inherent in FEL experiments.

20.
Clin Exp Dermatol ; 38(5): 507-10, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23777492

RESUMO

Immunocompromised areas of the skin, caused by chronic lymphoedema, paraplegia, infections or traumas, represent a site of regional neuroimmunocutaneous destabilization, termed the immunocompromised cutaneous district (ICD), in which malignancies and other opportunistic disorders are more likely to occur. We report the case of a metastatic porocarcinoma (PC) occurring on a lymphoedematous limb in a 72-year-old man. We reviewed the literature to better understand the potential pathogenetic mechanisms behind this condition. It has been reported that removal of the leg vein destroys the medial group of the superficial lymphatic vessels and alters the normal lymph drainage of the leg, predisposing to recurrent cellulitis. Our observations suggest that saphenous venectomy can induce development of an ICD. We suggest that PC, a rare cutaneous tumour, should be included in the growing list of tumours arising in the ICD.


Assuntos
Carcinoma/etiologia , Ponte de Artéria Coronária , Veia Safena/cirurgia , Neoplasias Cutâneas/etiologia , Idoso , Carcinoma/secundário , Humanos , Hospedeiro Imunocomprometido , Perna (Membro) , Linfedema/complicações , Masculino , Neoplasias Cutâneas/secundário
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