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1.
Palliat Support Care ; : 1-4, 2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37786362

RESUMO

OBJECTIVES: Opioid use disorder (OUD) and cancer gained attention as co-occurring diseases in the last 2 decades due to the possible relationship between opioid prescriptions for cancer pain and the risk of developing substance use disorder in cancer patients. However, little is known about patients previously diagnosed with OUD who develop cancer and how to manage both OUD symptoms and control pain. METHODS: The present case series deals with this subpopulation and proposes a dose escalation of methadone to control both the cancer-related pain and drug addiction symptoms. RESULTS: This approach is peculiar because methadone is not used as a first-line treatment in cancer pain management and is not often used as a second-line treatment as well. Our 4 patients experienced good clinical control of symptoms and no major adverse reactions. SIGNIFICANCE OF RESULTS: The subgroup of patients with OUD who develop cancer could be the perfect population to reconsider the use of methadone as a first-line treatment for cancer pain. Prospective studies are needed to evaluate the efficacy and safety of increasing doses of methadone in these patients to validate our clinical approach.

2.
Front Immunol ; 14: 1272798, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37841271

RESUMO

CAR-T therapy has revolutionized the treatment of relapsed/refractory B-cell malignancies. Patients who are receiving such therapy are susceptible to an increased incidence of infections due to post-treatment immunosuppression. The need for antifungal prophylaxis during the period of neutropenia remains to be determined. The clinical outcome of a 55-year-old patient with relapsed/refractory DLBCL who received axicabtagene ciloleucel is described here. The patient developed CRS grade II and ICANS grade IV requiring tocilizumab, prolonged use of steroids and anakinra. An invasive pulmonary aspergillosis arose after 1 month from CAR-T reinfusion, resolved with tracheal sleeve pneumonectomy. The patient is now in Complete Remission. This case suggests that antifungal prophylaxis should be considered. We have now included micafungin as a standard prophylaxis in our institution.


Assuntos
Infecções Fúngicas Invasivas , Receptores de Antígenos Quiméricos , Humanos , Pessoa de Meia-Idade , Antifúngicos/uso terapêutico , Recidiva Local de Neoplasia/tratamento farmacológico , Antígenos CD19/uso terapêutico , Infecções Fúngicas Invasivas/tratamento farmacológico , Infecções Fúngicas Invasivas/etiologia , Infecções Fúngicas Invasivas/prevenção & controle , Terapia Baseada em Transplante de Células e Tecidos
3.
Elife ; 112022 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-36413383

RESUMO

Background: Recent in-vitro data have shown that the activity of monoclonal antibodies (mAbs) targeting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) varies according to the variant of concern (VOC). No studies have compared the clinical efficacy of different mAbs against Omicron VOC. Methods: The MANTICO trial is a non-inferiority randomised controlled trial comparing the clinical efficacy of early treatments with bamlanivimab/etesevimab, casirivimab/imdevimab, and sotrovimab in outpatients aged 50 or older with mild-to-moderate SARS-CoV-2 infection. As the patient enrolment was interrupted for possible futility after the onset of the Omicron wave, the analysis was performed according to the SARS-CoV-2 VOC. The primary outcome was coronavirus disease 2019 (COVID-19) progression (hospitalisation, need of supplemental oxygen therapy, or death through day 14). Secondary outcomes included the time to symptom resolution, assessed using the product-limit method. Kaplan-Meier estimator and Cox proportional hazard model were used to assess the association with predictors. Log rank test was used to compare survival functions. Results: Overall, 319 patients were included. Among 141 patients infected with Delta, no COVID-19 progression was recorded, and the time to symptom resolution did not differ significantly between treatment groups (Log-rank Chi-square 0.22, p 0.90). Among 170 patients infected with Omicron (80.6% BA.1 and 19.4% BA.1.1), two COVID-19 progressions were recorded, both in the bamlanivimab/etesevimab group, and the median time to symptom resolution was 5 days shorter in the sotrovimab group compared with the bamlanivimab/etesevimab and casirivimab/imdevimab groups (HR 0.53 and HR 0.45, 95% CI 0.36-0.77 and 95% CI 0.30-0.67, p<0.01). Conclusions: Our data suggest that, among adult outpatients with mild-to-moderate SARS-CoV-2 infection due to Omicron BA.1 and BA.1.1, early treatment with sotrovimab reduces the time to recovery compared with casirivimab/imdevimab and bamlanivimab/etesevimab. In the same population, early treatment with casirivimab/imdevimab may maintain a role in preventing COVID-19 progression. The generalisability of trial results is substantially limited by the early discontinuation of the trial and firm conclusions cannot be drawn. Funding: This trial was funded by the Italian Medicines Agency (Agenzia Italiana del Farmaco, AIFA). The VOC identification was funded by the ORCHESTRA (Connecting European Cohorts to Increase Common and Effective Response to SARS-CoV-2 Pandemic) project, which has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement number 101016167. Clinical trial number: NCT05205759.


Assuntos
Tratamento Farmacológico da COVID-19 , SARS-CoV-2 , Humanos , Anticorpos Monoclonais/uso terapêutico , Resultado do Tratamento
4.
Front Aging Neurosci ; 14: 1003792, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36158556

RESUMO

Background: This study aims at reviewing, within the framework of motor neuron disease-frontotemporal degeneration (MND-FTD)-spectrum disorders, evidence on the co-occurrence between primary progressive aphasia (PPA) and MND in order to profile such a complex at pathological, genetic and clinical levels. Methods: This review was pre-registered (osf.io/ds8m4) and performed in accordance with the 2020 PRISMA guidelines. Case reports/series and group studies were included if addressing (1) progressive non-fluent aphasia (PNFA) or semantic dementia (SD) with MND or (2) MND patients with co-morbid PNFA/SD. Results: Out of 546 initial records, 56 studies were included. As to case reports/series (N = 35), which included 61 PPA-MND patients, the following findings yielded: (1) PNFA is more frequent than SD in PPA-MND; (2) in PPA-MND, the most prevalent motor phenotypes are amyotrophic lateral sclerosis and predominant-upper MND, with bulbar involvement being ubiquitous; (3) extrapyramidal features are moderately frequent in PPA-MND; (4) PPA-MND patients usually display frontotemporal, left-greater-than-right involvement; (5) TDP-43-B is the typical pathological substrate of PPA-MND; (6) TBK1 mutations represent the most frequent genetic risk factors for PPA-MND.As to group studies, including 121 patients, proportional meta-analytic procedures revealed that: (1) the lifetime prevalence of MND in PPA is 6%; (2) PPA occurs in 19% of patients with co-morbid MND and FTD; (3) MND is more frequent in PNFA (10%) than in SD patients (3%). Discussion: Insights herewith delivered into the clinical, neuropathological and genetic features of PPA-MND patients prompt further investigations aimed at improving clinical practice within the MND-FTD spectrum.

5.
EJNMMI Phys ; 9(1): 40, 2022 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-35666316

RESUMO

BACKGROUND: The Standardized Uptake Value (SUV) Max, SUVMean, and SUVPeak are metrics used to quantify positron emission tomography (PET) images. In order to assess the significance of a change in these metrics for diagnostic purposes, it is relevant to know their variation. The sources of variation can be biological or technical. In this study, we present a method to determine the statistical technical variation of SUV in PET images. RESULTS: This method was tested on a NEMA quality phantom with spheres of various diameters with a full-length acquisition time of 150 s per bed position and foreground-to-background activity ratio of F18-2-fluoro-2-deoxy-D-glucose (FDG) of 10:1. Our method divides the 150 s acquisition into subsets with statistically independent frames of shorter reconstruction length. SUVMax, Mean and Peak were calculated for each reconstructed image in a subset. The coefficient of variation of SUV within each subset has been used to estimate the expected coefficient of variation at 150 s reconstruction length. We report the largest coefficient of variation of the SUV metrics for the smallest sphere and the smallest variation for the largest sphere. The expected variation at 150 s reconstruction length does not exceed 6% for the smallest sphere and 2% for the largest sphere. CONCLUSIONS: With the presented method, we aim to determine the statistical technical variation of SUV. The method enables the evaluation of the effect of SUV metric choice (Max, Mean, Peak) and lesion size on the technical variation and, therefore, to evaluate its relevance on the total variation of the SUV value between clinical studies.

6.
Expert Opin Drug Discov ; 17(6): 531-546, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35361043

RESUMO

INTRODUCTION: The ongoing COVID19 pandemic represents an unprecedented opportunity to test the feasibility of monoclonal antibody (mAb) therapies against respiratory viruses. While many hurdles were easily predictable (e.g. time to develop, scalability, and economic sustainability), mAb cocktails (i.e. the combination of two mAbs) were finally deployed in 2021, one year after the beginning of the pandemic. Of them, the REGN-COV-2 cocktail was likely the most successful experience and contributed at saving lives at the time of the wave sustained by the Delta variant of concern (VOC). AREAS COVERED: Herein, the authors review the preclinical and clinical history of the casirivimab + imdevimab cocktail for the treatment of novel coronavirus infection. The authors furthermore provide the reader with their perspectives on this cocktail including its current place in the treatment armamentarium. EXPERT OPINION: Unfortunately, results from clinical trials highlighted a very limited efficacy in inpatients; furthermore, the current evidence with regards to its lack of effectiveness against the current dominant VOC (omicron) suggests a very limited use of these drugs in the future. In the authors' opinion, this story reminds us of the limitations of mAb therapies in pandemic settings, and of the inferiority of monoclonal versus polyclonal antibody-based therapeutics in such scenarios.


Assuntos
Tratamento Farmacológico da COVID-19 , SARS-CoV-2 , Anticorpos Monoclonais , Anticorpos Monoclonais Humanizados/farmacologia , Anticorpos Neutralizantes , Combinação de Medicamentos , Humanos
8.
Neurol Sci ; 43(2): 985-992, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34185185

RESUMO

BACKGROUND: Working memory (WM) abilities are frequently impaired in neurological disorders affecting fronto-parietal cortical/sub-cortical structures. WM deficits negatively influence interventional outcomes and everyday functioning. This study thus aimed at the following: (a) developing and standardizing an ecologically valid task for WM assessment ( Ice Cream Test, ICT); (b) validating and norming a novel WM test (Digit Ordering Test, DOT), as well as providing updated norms for digit span (DS) tasks, in an Italian population sample; (c) introducing a novel scoring procedure for measuring WM. METHODS: One-hundred and sixty-eight Italian healthy participants-73 male, 95 females; age: 48.4 ± 19.1 (18-86); education: 12.1 ± 4.8 (4-21)-underwent a thorough WM assessment-DOT, ICT, and both forward and backward DS tasks (FDS, BDS). The ICT requires participants to act as waiters who have to keep track of customers' orders. For each task, WM and total (T) outcomes were computed, i.e., the number of elements in the longest sequence and that of recalled sequences, respectively. Norms were derived via the equivalent score (ES) method. RESULTS: DS ratios (DSRs) were computed for both WM/S and T outcomes on raw DS measures (BDS divided by FDS). Age and education significantly predicted all WM tasks; sex affected FDS and DSR-T scores (males > females). WM measures were highly internally related. DISCUSSION: The present work provides Italian practitioners with a normatively updated, multi-component, adaptive battery for WM assessment (WoMAB) as well as with novel outcomes which capture different WM facets-WM capacity and attentive monitoring abilities.


Assuntos
Cognição , Memória de Curto Prazo , Adulto , Idoso , Atenção , Feminino , Humanos , Masculino , Transtornos da Memória , Rememoração Mental , Pessoa de Meia-Idade , Testes Neuropsicológicos
9.
Leuk Lymphoma ; 62(4): 828-836, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33274677

RESUMO

Anti-CD19 chimeric antigen receptor (CAR) T cells represent the first approved third-line therapy associated with long-term remissions in patients with refractory/relapsed (R/R) diffuse large B-cell lymphoma (DLBCL). Eligibility criteria to identify patients who can successfully receive CAR-T are still debated. For this reason, the aim of this study was to identify factors influencing eligibility and define a realistic patient estimate. Of 1100 DLBCL patients, 137 were included. Based on the Juliet trial inclusion criteria, only 64 patients (46.7%) would be eligible. Median overall survival (OS) was 8.04 months in eligible vs 3.23 in non-eligible patients (p < 0.001). Multivariate analysis identified stage III-IV (p = 0.017) and ECOG ≥2 (p < 0.001) as significant independent prognostic factors for OS. Moreover, only 64/1100 (5.8%) DLBCL patients would be truly eligible for CAR-T. Our real-life data confirm that with a  longer waiting time patients with advanced stage and poor ECOG are less likely to be eligible for CAR-T cell infusion.


Assuntos
Linfoma Difuso de Grandes Células B , Receptores de Antígenos Quiméricos , Antígenos CD19 , Terapia Baseada em Transplante de Células e Tecidos , Humanos , Imunoterapia Adotiva , Linfoma Difuso de Grandes Células B/terapia
11.
Hematol Oncol ; 38(4): 589-596, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32588912

RESUMO

The anticoagulant treatment for patients with hematologic malignancies is low molecular weight heparin (LMWH), which is considered the safest in this particular patients setting. Although direct oral anticoagulants (DOACs) have proven their efficacy and safety in patients with cancer, their use can be challenging in patients with hematologic malignancies due to the peculiarity of these neoplasms: high thrombotic risk, possible onset of thrombocytopenia and concomitant anticancer therapies. The aim of our study was to evaluate the efficacy and safety of DOACs for venous thromboembolism or atrial fibrillation in patients with hematologic malignancies and plasmatic DOACs level during anticancer therapy and at time of bleeding or thrombotic complications. We evaluated patients with hematologic malignancies treated with DOACs for venous thromboembolism or atrial fibrillation-therapy was maintained until the platelet count was ≥50 × 109 /L. In case of concomitant anticancer treatment and haemorrhagic or thrombotic events, we checked DOACs plasma levels (trough and peak). The patients evaluated were 135: 104/135 were on anticancer therapy. We did not observe either thrombotic or major haemorrhagic adverse events. Minor bleedings occurred in 10 patients and clinical relevant non-major (CRNM) in two patients. There was a statistically significant correlation between bleedings and myelodysplastic syndrome. DOACs resulted effective and safe in patients with hematologic malignancies. DOACs plasma level can be helpful in suggesting an early dose adjustment to prevent haemorrhagic adverse event in patients on concomitant anticancer therapy. Larger prospective studies including hematologic patients are warranted to confirm the safety and efficacy of DOACs.


Assuntos
Anticoagulantes/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Fibrilação Atrial/tratamento farmacológico , Neoplasias Hematológicas/tratamento farmacológico , Hemorragia/tratamento farmacológico , Tromboembolia Venosa/tratamento farmacológico , Administração Oral , Adulto , Idoso , Idoso de 80 Anos ou mais , Fibrilação Atrial/induzido quimicamente , Fibrilação Atrial/patologia , Feminino , Seguimentos , Neoplasias Hematológicas/patologia , Hemorragia/induzido quimicamente , Hemorragia/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Tromboembolia Venosa/induzido quimicamente , Tromboembolia Venosa/patologia
12.
Histochem Cell Biol ; 152(3): 195-206, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31179519

RESUMO

Desmosomal cadherins, desmocollins, and desmogleins are cholesterol-dependent entities responsible for the stable adhesion of desmosomes in epithelial cells. Here, we investigated the influence of cellular cholesterol depletion on the dynamic properties of the desmosomal cadherin desmocollin, particularly the lateral mobility and distribution of desmocollin 2 (Dsc2-YFP) in the plasma membrane, and how these properties influence the adhesion strength of desmosomes. Depletion of cellular cholesterol decreased the lateral mobility of Dsc2-YFP and caused dispersion of Dsc2-YFP in the plasma membrane of epithelial MDCK cells. As a consequence of the altered Dsc2-YFP dynamics, the adhesive strength of desmosomes was weakened. Moreover, our study is the first to show and quantify the co-association of desmosomes with cholesterol/sphingomyelin-enriched membrane domains at the ultrastructural level. Taken together, our data emphasize a critical role for the cellular cholesterol content in regulating the lateral mobility and distribution of Dsc2 and show that cholesterol depletion reduces the strength of desmosomal adhesions.


Assuntos
Colesterol/metabolismo , Caderinas de Desmossomos/metabolismo , Desmossomos/metabolismo , Animais , Membrana Celular/química , Membrana Celular/metabolismo , Células Cultivadas , Colesterol/deficiência , Cães , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Células Madin Darby de Rim Canino
13.
Sci Rep ; 8(1): 17133, 2018 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-30459350

RESUMO

Tunneling membrane nanotubes (TnTs) are membrane protrusions connecting nearby or distant cells in vitro and in vivo. Functions of TnTs in cellular processes are various and rely on TnT structure, which also depends on cytoskeletal composition. In the present study, we focused on the organization of microtubules (MTs) and intermediate filaments (IFs) in TnTs of urothelial cells. We analysed TnTs of normal porcine urothelial cells, which morphologically and physiologically closely resemble normal human urothelial cells, and of cancer cells derived from invasive human urothelial neoplasm. Wide-field fluorescence, confocal and super-resolution microscopy techniques, together with image analyses and 3D reconstructions enlightened specific MT-IF organization in TnTs, and for the first time revealed that MTs and IFs co-occur in the majority of normal and cancer urothelial cell TnTs. Our findings show that in the initiation segment of TnTs, MTs are cross-linked with each other into filamentous network, however in the middle and the attaching segment of TnT, MTs can helically enwrap IFs, the phenomenon that has not been shown before within the TnTs. In this study, we assess MT-IF co-occurrence in TnTs and present evidence that such helical organization of MTs enwrapping IFs is only occurring in a minority of the TnTs. We also discuss the possible cell-biological and physiological reasons for helical organization of MTs in TnTs.


Assuntos
Membrana Celular/ultraestrutura , Microtúbulos/ultraestrutura , Neoplasias da Bexiga Urinária/patologia , Urotélio/citologia , Animais , Membrana Celular/metabolismo , Células Cultivadas , Humanos , Filamentos Intermediários/metabolismo , Filamentos Intermediários/ultraestrutura , Microtúbulos/metabolismo , Suínos
15.
Methods Appl Fluoresc ; 5(1): 015002, 2017 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-28120817

RESUMO

Re-scan confocal microscopy (RCM) is a new super-resolution technique based on a standard confocal microscope extended with a re-scan unit in the detection path that projects the emitted light onto a sensitive camera. In this paper the fundamental properties of RCM, lateral resolution, axial resolution and signal-to-noise ratio, are characterized and compared with properties of standard confocal microscopy. The results show that the lateral resolution of RCM is ~170 nm compared to ~240 nm of confocal microscopy for 488 nm excitation and 1.49 NA. As the theory predicts, this improved lateral resolution is independent of the pinhole diameter. In standard confocal microscopy, the same lateral resolution can only be achieved with an almost closed pinhole and, consequently, with a major loss of signal. We show that the sectioning capabilities of the standard confocal microscope are preserved in RCM and that the axial resolution of RCM is slightly better (~15%) than the standard confocal microscope. Furthermore, the signal-to-noise ratio in RCM is a factor of 2 higher than in standard confocal microscopy, also due to the use of highly sensitive modern cameras. In case the pinhole of a confocal microscope is adjusted in such way that the lateral resolution is comparable to that of RCM, the signal-to-noise ratio in RCM is 4 times higher than standard confocal microscopy. Therefore, RCM offers a good alternative to standard confocal microscopy for higher lateral resolution with the main advantage of strongly improved sensitivity.

16.
PLoS One ; 11(2): e0149601, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26913505

RESUMO

HIV-infected patients appear to have a significantly greater risk of non-AIDS comorbidities such as osteoporosis and atherosclerosis. Subjects with osteoporosis are at a higher risk of developing cardiovascular disease than those with normal bone mass, therefore a possible relation between these two conditions can be hypothesized. In the setting of HIV infection, several factors might contribute to bone disease and endothelial dysfunction. The aim of our study was to evaluate the relationship between bone and cardiovascular disease and to investigate the role of traditional factors, T-cell phenotype and osteoprotegerin in HIV positive subjects on effective antiretroviral therapy. We included 94 HIV positive subjects on antiretroviral therapy with virological suppression and 41 healthy subjects matched for age and gender as a control group. Carotid-Intima Media Thickness (c-IMT) and bone mineral density (BMD) were performed by ultrasound and DEXA, respectively. CD4+/CD8+ T-cell activation, senescence and osteoprotegerin plasma levels were measured by flow-cytometry and ELISA, respectively. Among HIV positive patients, 56.4% had osteopenia/osteoporosis and 45.7% had pathological c-IMT (>0.9 mm). Subjects with pathological c-IMT and BMD exhibited higher CD4+ and CD8+ activated, CD8+ senescent and osteoprotegerin than subjects with normal c-IMT and BMD. HIV positive subjects with osteopenia/osteoporosis had higher c-IMT than subjects with normal BMD, and linear regression analysis showed a negative correlation between BMD and c-IMT. Several factors are implicated in the pathogenesis of non-AIDS comorbidities in HIV positive patients. Osteoprotegerin together with inflammation and immunosenescence in HIV positive patients could affect bone and vascular system and could be considered as a possible common link between these two diseases.


Assuntos
Doenças Ósseas/epidemiologia , Doenças Cardiovasculares/epidemiologia , Infecções por HIV/imunologia , Infecções por HIV/metabolismo , Imunossenescência , Osteoprotegerina/metabolismo , Fármacos Anti-HIV/uso terapêutico , Biomarcadores/metabolismo , Doenças Cardiovasculares/diagnóstico por imagem , Espessura Intima-Media Carotídea , Comorbidade , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Linfócitos T/patologia
17.
Mediators Inflamm ; 2014: 192594, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25374442

RESUMO

HIV-infected patients have a significantly greater risk of cardiovascular disease. Several markers including osteoprotegerin have been shown to be involved in the development and progression of atherosclerosis. We investigated the relationship between T-cell phenotype, osteoprotegerin, and atherosclerosis evaluated by carotid intima-media thickness (c-IMT) in 94 HIV+ patients on suppressive antiretroviral therapy with Framingham score <10%. As for the control group, 24 HIV-negative subjects were enrolled. c-IMT was assessed by ultrasound. CD4+/CD8+ T-cell activation (CD38+ HLADR+) and senescence (CD57+ CD28-) were measured by flow cytometry. IL-6 and OPG levels were measured by ELISA kit. c-IMT was higher in HIV+ than in controls. Among HIV+ patients, 44.7% had pathological c-IMT (≥0.9 mm). CD8+ T-cell activation and senescence and OPG plasma levels were higher in HIV+ patients than in controls. Subjects with pathological c-IMT exhibited higher CD8+ immune activation and immunosenescence and OPG levels than subjects with normal c-IMT. Multivariate analysis showed that age, CD8+ CD38+ HLADR+, and CD8+ CD28- CD57+ were independently associated with pathological c-IMT. Several factors have been implicated in the pathogenesis of atherosclerosis in HIV patients. Immune activation and immunosenescence of CD8+ T cell together with OPG plasma levels might be associated with the development and progression of early atherosclerosis, even in the case of viral suppression.


Assuntos
Aterosclerose/etiologia , Aterosclerose/imunologia , Infecções por HIV/complicações , Infecções por HIV/imunologia , Osteoprotegerina/sangue , Adulto , Fármacos Anti-HIV/uso terapêutico , Biomarcadores/sangue , Linfócitos T CD8-Positivos/imunologia , Espessura Intima-Media Carotídea , Estudos de Casos e Controles , Senescência Celular/imunologia , Progressão da Doença , Feminino , Infecções por HIV/tratamento farmacológico , Humanos , Interleucina-6/sangue , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade
18.
J Vis Exp ; (87)2014 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-24835130

RESUMO

Dendritic spines are protrusions emerging from the dendrite of a neuron and represent the primary postsynaptic targets of excitatory inputs in the brain. Technological advances have identified these structures as key elements in neuron connectivity and synaptic plasticity. The quantitative analysis of spine morphology using light microscopy remains an essential problem due to technical limitations associated with light's intrinsic refraction limit. Dendritic spines can be readily identified by confocal laser-scanning fluorescence microscopy. However, measuring subtle changes in the shape and size of spines is difficult because spine dimensions other than length are usually smaller than conventional optical resolution fixed by light microscopy's theoretical resolution limit of 200 nm. Several recently developed super resolution techniques have been used to image cellular structures smaller than the 200 nm, including dendritic spines. These techniques are based on classical far-field operations and therefore allow the use of existing sample preparation methods and to image beyond the surface of a specimen. Described here is a working protocol to apply super resolution structured illumination microscopy (SIM) to the imaging of dendritic spines in primary hippocampal neuron cultures. Possible applications of SIM overlap with those of confocal microscopy. However, the two techniques present different applicability. SIM offers higher effective lateral resolution, while confocal microscopy, due to the usage of a physical pinhole, achieves resolution improvement at the expense of removal of out of focus light. In this protocol, primary neurons are cultured on glass coverslips using a standard protocol, transfected with DNA plasmids encoding fluorescent proteins and imaged using SIM. The whole protocol described herein takes approximately 2 weeks, because dendritic spines are imaged after 16-17 days in vitro, when dendritic development is optimal. After completion of the protocol, dendritic spines can be reconstructed in 3D from series of SIM image stacks using specialized software.


Assuntos
Espinhas Dendríticas/ultraestrutura , Hipocampo/diagnóstico por imagem , Microscopia/métodos , Neurônios/ultraestrutura , Animais , Imageamento Tridimensional/métodos , Ratos , Ultrassonografia
19.
Biomed Opt Express ; 4(11): 2644-56, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24298422

RESUMO

We present a new super-resolution technique, Re-scan Confocal Microscopy (RCM), based on standard confocal microscopy extended with an optical (re-scanning) unit that projects the image directly on a CCD-camera. This new microscope has improved lateral resolution and strongly improved sensitivity while maintaining the sectioning capability of a standard confocal microscope. This simple technology is typically useful for biological applications where the combination high-resolution and high-sensitivity is required.

20.
Stem Cells ; 31(11): 2478-91, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23897741

RESUMO

Satellite cells are mitotically quiescent myogenic stem cells resident beneath the basal lamina surrounding adult muscle myofibers. In response to injury, multiple extrinsic signals drive the entry of satellite cells into the cell cycle and then to proliferation, differentiation, and self-renewal of their downstream progeny. Because satellite cells must endure for a lifetime, their cell cycle activity must be carefully controlled to coordinate proliferative expansion and self-renewal with the onset of the differentiation program. In this study, we find that cyclin D3, a member of the family of mitogen-activated D-type cyclins, is critically required for proper developmental progression of myogenic progenitors. Using a cyclin D3-knockout mouse we determined that cyclin D3 deficiency leads to reduced myofiber size and impaired establishment of the satellite cell population within the adult muscle. Cyclin D3-null myogenic progenitors, studied ex vivo on isolated myofibers and in vitro, displayed impaired cell cycle progression, increased differentiation potential, and reduced self-renewal capability. Similarly, silencing of cyclin D3 in C2 myoblasts caused anticipated exit from the cell cycle and precocious onset of terminal differentiation. After induced muscle damage, cyclin D3-null myogenic progenitors exhibited proliferation deficits, a precocious ability to form newly generated myofibers and a reduced capability to repopulate the satellite cell niche at later stages of the regeneration process. These results indicate that cyclin D3 plays a cell-autonomous and nonredundant function in regulating the dynamic balance between proliferation, differentiation, and self-renewal that normally establishes an appropriate pool size of adult satellite cells.


Assuntos
Ciclina D3/fisiologia , Células Satélites de Músculo Esquelético/fisiologia , Células-Tronco/fisiologia , Animais , Diferenciação Celular/fisiologia , Processos de Crescimento Celular/fisiologia , Ciclina D3/metabolismo , Masculino , Camundongos , Camundongos Knockout , Regeneração/fisiologia , Células Satélites de Músculo Esquelético/citologia , Células Satélites de Músculo Esquelético/metabolismo , Células-Tronco/citologia , Células-Tronco/metabolismo , Transfecção
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