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1.
Lett Appl Microbiol ; 71(6): 652-659, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32916001

RESUMO

The emergence of novel resistant markers hampers the efficacy of beta-lactam antibiotics to treat infections caused by micro-organisms carrying such resistances. This study investigated the antimicrobial susceptibility pattern, the carpapenem-associated determinants and the molecular epidemiology of Klebsiella pneumoniae showing a New Delhi (NDM) metallo-ß-lactamase phenotype, isolated from a patient admitted to intensive care unit of the main hospital for acute care of Molise region, central Italy. Antimicrobial susceptibility was assessed for nineteen antibiotics by disc diffusion and agar dilution methods. Carbapenem-associated resistance determinants were detected through gene-specific amplifications, targeting blaNDM-1 , blaSHV and blaTEM , blaCTX-M , blaKPC , blaVIM , blaIMP , blaGES and blaOXA-48-lixe . Molecular characterization was carried out through multilocus sequence typing. The strain showed a multidrug resistant profile, and PCR and sequencing confirmed the presence of blaNDM-1 gene. Among the multiple resistance-associated determinants tested, the isolate, which was assigned to the sequence type ST11, only harboured blaSHV and blaTEM genes. This is the first report of NDM-1 variant in the regional healthcare setting for acute patients, raising significant concerns about the increase in the antimicrobials resistance spread through a different mechanism from the endemic KPC carbapenemase, and underlining the circulation of a virulent clone never identified before in this area.


Assuntos
Proteínas de Bactérias/metabolismo , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/isolamento & purificação , beta-Lactamases/metabolismo , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Farmacorresistência Bacteriana , Hospitais/estatística & dados numéricos , Humanos , Itália/epidemiologia , Infecções por Klebsiella/epidemiologia , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/enzimologia , Klebsiella pneumoniae/genética , Masculino , Testes de Sensibilidade Microbiana , Epidemiologia Molecular , Tipagem de Sequências Multilocus , beta-Lactamases/genética
2.
Phys Rev Lett ; 122(18): 181102, 2019 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-31144869

RESUMO

In this paper, we present the analysis and results of a direct measurement of the cosmic-ray proton spectrum with the CALET instrument onboard the International Space Station, including the detailed assessment of systematic uncertainties. The observation period used in this analysis is from October 13, 2015 to August 31, 2018 (1054 days). We have achieved the very wide energy range necessary to carry out measurements of the spectrum from 50 GeV to 10 TeV covering, for the first time in space, with a single instrument the whole energy interval previously investigated in most cases in separate subranges by magnetic spectrometers (BESS-TeV, PAMELA, and AMS-02) and calorimetric instruments (ATIC, CREAM, and NUCLEON). The observed spectrum is consistent with AMS-02 but extends to nearly an order of magnitude higher energy, showing a very smooth transition of the power-law spectral index from -2.81±0.03 (50-500 GeV) neglecting solar modulation effects (or -2.87±0.06 including solar modulation effects in the lower energy region) to -2.56±0.04 (1-10 TeV), thereby confirming the existence of spectral hardening and providing evidence of a deviation from a single power law by more than 3σ.

3.
Phys Rev Lett ; 120(26): 261102, 2018 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-30004739

RESUMO

Extended results on the cosmic-ray electron + positron spectrum from 11 GeV to 4.8 TeV are presented based on observations with the Calorimetric Electron Telescope (CALET) on the International Space Station utilizing the data up to November 2017. The analysis uses the full detector acceptance at high energies, approximately doubling the statistics compared to the previous result. CALET is an all-calorimetric instrument with a total thickness of 30 X_{0} at normal incidence and fine imaging capability, designed to achieve large proton rejection and excellent energy resolution well into the TeV energy region. The observed energy spectrum in the region below 1 TeV shows good agreement with Alpha Magnetic Spectrometer (AMS-02) data. In the energy region below ∼300 GeV, CALET's spectral index is found to be consistent with the AMS-02, Fermi Large Area Telescope (Fermi-LAT), and Dark Matter Particle Explorer (DAMPE), while from 300 to 600 GeV the spectrum is significantly softer than the spectra from the latter two experiments. The absolute flux of CALET is consistent with other experiments at around a few tens of GeV. However, it is lower than those of DAMPE and Fermi-LAT with the difference increasing up to several hundred GeV. The observed energy spectrum above ∼1 TeV suggests a flux suppression consistent within the errors with the results of DAMPE, while CALET does not observe any significant evidence for a narrow spectral feature in the energy region around 1.4 TeV. Our measured all-electron flux, including statistical errors and a detailed breakdown of the systematic errors, is tabulated in the Supplemental Material in order to allow more refined spectral analyses based on our data.

4.
J Environ Manage ; 223: 1078-1085, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-30096748

RESUMO

Microalgae cultivation systems fed with wastewater as source of nutrients represents the principal sustainable condition to produce microalgal biomass to be converted conveniently to biofuels. In order to optimize microalgae growth and their lipid content, the effect of light intensity and nutrients load in real wastewater was investigated through batch microalgal cultivation tests. A microalgal polyculture was used as inoculum and grown for 10 days in batch at different conditions of light intensity (i.e. 20, 50 and 100 µmol s-1m-2) and nutrients concentration in wastewater. Experimental results showed that biomass productivity decreased for rich nutrients conditions and increased for high light intensities. The highest lipid mass content (29%) was found for high light intensity condition (100 µmol s-1m-2). Furthermore, microalgae settleability tests, conducted at the end of the cultivation time, resulted in the highest biomass recovery efficiency (72%) for low light intensity and nutrients supply conditions.


Assuntos
Lipídeos/análise , Microalgas , Águas Residuárias , Biocombustíveis , Biomassa
5.
Water Sci Technol ; 77(3-4): 1062-1071, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29488969

RESUMO

A mixed culture of oleaginous yeast Lipomyces starkeyi and wastewater native microalgae (mostly Scenedesmus sp. and Chlorella sp.) was performed to enhance lipid and biomass production from urban wastewaters. A 400 L raceway pond, operating outdoors, was designed and used for biomass cultivation. Microalgae and yeast were inoculated into the cultivation pond with a 2:1 inoculum ratio. Their concentrations were monitored for 14 continuous days of batch cultivation. Microalgal growth presented a 3-day initial lag-phase, while yeast growth occurred in the first few days. Yeast activity during the microalgal lag-phase enhanced microalgal biomass productivity, corresponding to 31.4 mgTSS m-2 d-1. Yeast growth was limited by low concentrations in wastewater of easily assimilated organic substrates. Organic carbon was absorbed in the first 3 days with a 3.7 mgC L-1 d-1 removal rate. Complete nutrient removal occurred during microalgal linear growth with 2.9 mgN L-1 d-1 and 0.96 mgP L-1 d-1 removal rates. Microalgal photosynthetic activity induced high pH and dissolved oxygen values resulted in natural bactericidal and antifungal activity. A 15% lipid/dry weight was measured at the end of the cultivation time. Fatty acid methyl ester (FAME) analysis indicated that the lipids were mainly composed of arachidic acid.


Assuntos
Chlorella , Lipomyces , Microalgas , Scenedesmus , Eliminação de Resíduos Líquidos/métodos , Biocombustíveis , Biomassa , Chlorella/crescimento & desenvolvimento , Chlorella/metabolismo , Lipídeos/biossíntese , Lipomyces/crescimento & desenvolvimento , Lipomyces/metabolismo , Microalgas/crescimento & desenvolvimento , Microalgas/metabolismo , Projetos Piloto , Lagoas , Scenedesmus/crescimento & desenvolvimento , Scenedesmus/metabolismo , Águas Residuárias
6.
Phys Rev Lett ; 119(18): 181101, 2017 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-29219544

RESUMO

First results of a cosmic-ray electron and positron spectrum from 10 GeV to 3 TeV is presented based upon observations with the CALET instrument on the International Space Station starting in October, 2015. Nearly a half million electron and positron events are included in the analysis. CALET is an all-calorimetric instrument with total vertical thickness of 30 X_{0} and a fine imaging capability designed to achieve a large proton rejection and excellent energy resolution well into the TeV energy region. The observed energy spectrum over 30 GeV can be fit with a single power law with a spectral index of -3.152±0.016 (stat+syst). Possible structure observed above 100 GeV requires further investigation with increased statistics and refined data analysis.

7.
Vestn Oftalmol ; 133(4): 65-67, 2017.
Artigo em Russo | MEDLINE | ID: mdl-28980568

RESUMO

Corneal cross-linking (CXL) is aimed at halting the progression of keratoconus and is widely considered to be the golden standard in its treatment. It is usually contraindicated, however, in patients with corneal thickness of less than 400 µm, leaving the ophthalmic surgeon no option, but to perform transepithelial CXL (epi-on), usually regarded as less effective. We report a novel approach for ultrathin corneas with severe keratoconus - peripheral corneal cross-linking (P-CXL), in which corneal epithelium is still removed but the apex of the cornea is left untouched. Hypo-osmolar riboflavin solution is used as well. P-CXL was performed on a remarkably developed stage IV keratoconus with the thinnest pachymetry of 215 µm, Kmax of 88.1 D and astigmatism of 11.2 D. Four months after P-CXL, the thinnest pachymetry increased by 42 µm, Kmax decreased by 1.4 D, and astigmatism also decreased by 3.2 D.


Assuntos
Córnea , Ceratocone , Fotoquimioterapia/métodos , Riboflavina/administração & dosagem , Córnea/patologia , Córnea/cirurgia , Paquimetria Corneana/métodos , Progressão da Doença , Humanos , Ceratocone/diagnóstico , Ceratocone/fisiopatologia , Ceratocone/terapia , Masculino , Pessoa de Meia-Idade , Fármacos Fotossensibilizantes/administração & dosagem , Cuidados Pós-Operatórios/métodos , Índice de Gravidade de Doença , Resultado do Tratamento
8.
Phys Rev Lett ; 116(24): 241105, 2016 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-27367381

RESUMO

Cosmic-ray electrons and positrons are a unique probe of the propagation of cosmic rays as well as of the nature and distribution of particle sources in our Galaxy. Recent measurements of these particles are challenging our basic understanding of the mechanisms of production, acceleration, and propagation of cosmic rays. Particularly striking are the differences between the low energy results collected by the space-borne PAMELA and AMS-02 experiments and older measurements pointing to sign-charge dependence of the solar modulation of cosmic-ray spectra. The PAMELA experiment has been measuring the time variation of the positron and electron intensity at Earth from July 2006 to December 2015 covering the period for the minimum of solar cycle 23 (2006-2009) until the middle of the maximum of solar cycle 24, through the polarity reversal of the heliospheric magnetic field which took place between 2013 and 2014. The positron to electron ratio measured in this time period clearly shows a sign-charge dependence of the solar modulation introduced by particle drifts. These results provide the first clear and continuous observation of how drift effects on solar modulation have unfolded with time from solar minimum to solar maximum and their dependence on the particle rigidity and the cyclic polarity of the solar magnetic field.

9.
Phys Rev Lett ; 115(11): 111101, 2015 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-26406816

RESUMO

In this work we present results of a direct search for strange quark matter (SQM) in cosmic rays with the PAMELA space spectrometer. If this state of matter exists it may be present in cosmic rays as particles, called strangelets, having a high density and an anomalously high mass-to-charge (A/Z) ratio. A direct search in space is complementary to those from ground-based spectrometers. Furthermore, it has the advantage of being potentially capable of directly identifying these particles, without any assumption on their interaction model with Earth's atmosphere and the long-term stability in terrestrial and lunar rocks. In the rigidity range from 1.0 to ∼1.0×10^{3} GV, no such particles were found in the data collected by PAMELA between 2006 and 2009. An upper limit on the strangelet flux in cosmic rays was therefore set for particles with charge 1≤Z≤8 and mass 4≤A≤1.2×10^{5}. This limit as a function of mass and as a function of magnetic rigidity allows us to constrain models of SQM production and propagation in the Galaxy.

10.
Nature ; 458(7238): 607-9, 2009 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-19340076

RESUMO

Antiparticles account for a small fraction of cosmic rays and are known to be produced in interactions between cosmic-ray nuclei and atoms in the interstellar medium, which is referred to as a 'secondary source'. Positrons might also originate in objects such as pulsars and microquasars or through dark matter annihilation, which would be 'primary sources'. Previous statistically limited measurements of the ratio of positron and electron fluxes have been interpreted as evidence for a primary source for the positrons, as has an increase in the total electron+positron flux at energies between 300 and 600 GeV (ref. 8). Here we report a measurement of the positron fraction in the energy range 1.5-100 GeV. We find that the positron fraction increases sharply over much of that range, in a way that appears to be completely inconsistent with secondary sources. We therefore conclude that a primary source, be it an astrophysical object or dark matter annihilation, is necessary.

11.
J Oncol Pharm Pract ; 21(5): 396-9, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24748580

RESUMO

Ampullary carcinoma is an uncommon gastrointestinal disease. Its natural history is often characterized by the occurrence of liver metastases. Among patients who undergo pancreatoduodenectomy, those presenting with lymph nodes involvement are more prone to early distant disease relapse. In this report, a patient previously diagnosed with ampullary carcinoma had been treated with curative surgery. After subsequent adjuvant gemcitabine, the patient developed significant myelotoxicity and suffered from a single liver metastasis a few months later. A hepatic intra-arterial mitomycin plus fluorouracil-based chemotherapy was administered in order to avoid any serious systemic toxicity. The treatment was well tolerated and no serious side effects occurred. Extra-hepatic cancer relapse, involving intra-thoracic and abdominal lymph nodes, was observed not long after the initial intra-hepatic almost complete response. In conclusion, the locoregional chemotherapy administration was effective in overcoming any systemic toxicities and showed activity against the liver metastasis but it did not prevent extra-hepatic cancer dissemination.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias do Ducto Colédoco/patologia , Neoplasias Hepáticas/tratamento farmacológico , Idoso , Ampola Hepatopancreática/patologia , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias do Ducto Colédoco/terapia , Artéria Hepática , Humanos , Infusões Intra-Arteriais , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/secundário , Masculino , Mitomicina/administração & dosagem
12.
Phys Rev Lett ; 111(8): 081102, 2013 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-24010424

RESUMO

Precision measurements of the positron component in the cosmic radiation provide important information about the propagation of cosmic rays and the nature of particle sources in our Galaxy. The satellite-borne experiment PAMELA has been used to make a new measurement of the cosmic-ray positron flux and fraction that extends previously published measurements up to 300 GeV in kinetic energy. The combined measurements of the cosmic-ray positron energy spectrum and fraction provide a unique tool to constrain interpretation models. During the recent solar minimum activity period from July 2006 to December 2009, approximately 24,500 positrons were observed. The results cannot be easily reconciled with purely secondary production, and additional sources of either astrophysical or exotic origin may be required.

13.
J Oncol Pharm Pract ; 19(3): 202-7, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23034407

RESUMO

BACKGROUND: Mitomycin and irinotecan are widely used in the treatment of colorectal cancer, furthermore both of these drugs are active agents against nonsmall cell lung cancer and their combination has shown synergism in preclinical studies. The aim of the study was to evaluate the efficacy and safety of mitomycin- and irinotecan-based chemotherapy combination in patients with advanced nonsmall cell lung cancer progressing after previous antineoplastic therapies. METHODS: Thirty-one consecutive patients suffering from nonsmall cell lung cancer, who underwent mitomycin- plus irinotecan-based chemotherapy as salvage treatment after failure of at least two previous systemic treatments, were retrospectively identified in our database. Between September 2003 and March 2011, 31 patients with histologically proven stage IIIB or IV nonsmall cell lung cancer, received mitomycin 5 mg/m(2) on day 1 followed by irinotecan 150 mg/m(2) on day 2. Cycles were repeated at 2-week interval. RESULTS: A total of 164 cycles of treatment were given with a median of five per patient (range 1-10). The objective responses included partial response in 6 patients (19.3%), stable disease in 4 (13%), and progressive disease in 21 (67.7%). Median time to disease progression was 4 months, and median survival was 9+ months. Twelve patients (38%) reached 1-year survival. Grade 3-4 toxicities occurred in seven patients (22.5%), mainly myelosuppression (neutropenia, anemia, and thrombocytopenia), mucositis, and diarrhea. No treatment-related death was recorded. CONCLUSION: The mitomycin- and irinotecan-based combination chemotherapy seems to be tolerated and active in this subset of heavily pretreated patients with advanced nonsmall cell lung cancer. However, evaluation or recruitment of a larger number of patients would be needed to provide more adequate data on safety and activity of the described combination.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Camptotecina/administração & dosagem , Camptotecina/efeitos adversos , Camptotecina/análogos & derivados , Carcinoma Pulmonar de Células não Pequenas/patologia , Progressão da Doença , Feminino , Humanos , Irinotecano , Masculino , Pessoa de Meia-Idade , Mitomicina/administração & dosagem , Mitomicina/efeitos adversos , Estudos Retrospectivos
14.
SAGE Open Med Case Rep ; 11: 2050313X231158483, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36896327

RESUMO

Occurrence of venous thromboembolism in cancer patients (patients) undergoing chemotherapy is a remarkable concern for the oncologist. In addition, careful attention has to be paid to the possible major bleeding when patients carrying gastrointestinal cancer need antithrombotic therapies. To date some Cancer Associated Thrombosis (CAT) risk scores as Khorana and PROTECHT score have been developed to identify the cancer population at high-risk for venous thromboembolism (VTE). Consensus guidelines recommend to consider also low molecular weight heparin (LMWH) for primary thromboprophylaxis in high-risk patients. This is a report on a retrospective case series of 15 intra-luminal not surgically treated gastrointestinal cancer patients deemed high risk for VTE. The patients had a Khorana or PROTECHT score of 2 points or more (at least ≥ 2 points). They were undergoing first line chemotherapy in the absence of endoscopic signs of cancer spontaneous bleeding. A prophylactic dose of LMWH was administered just before starting the chemotherapy session and until 48 hours after its completion. The authors mainly aimed to report occurrence of clinically perceptible gastrointestinal bleeding events. Fifteen patients were administered LMWH - median age: 59 (range: 42-79); gender: male 12 (80%); tumor type: stomach - 13 patients (86%); gastro-esophageal junction: 2 patients (14%). Duration of heparin treatment: the total treatment duration was 228 days; mean 15.2 days (range: 5-45); nadroparin: mean 14.7 days (range: 5-45); enoxaparin: mean 10.1 days (range: 5-20); parnaparin: a total of 5 days. None of the patients experienced perceptible gastrointestinal bleeding. Short-term LMWH thromboprophylaxis appeared to be safe for this series of patients.

15.
Phys Rev Lett ; 106(20): 201101, 2011 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-21668214

RESUMO

Precision measurements of the electron component in the cosmic radiation provide important information about the origin and propagation of cosmic rays in the Galaxy. Here we present new results regarding negatively charged electrons between 1 and 625 GeV performed by the satellite-borne experiment PAMELA. This is the first time that cosmic-ray e⁻ have been identified above 50 GeV. The electron spectrum can be described with a single power-law energy dependence with spectral index -3.18 ± 0.05 above the energy region influenced by the solar wind (> 30 GeV). No significant spectral features are observed and the data can be interpreted in terms of conventional diffusive propagation models. However, the data are also consistent with models including new cosmic-ray sources that could explain the rise in the positron fraction.

16.
Phys Rev Lett ; 105(12): 121101, 2010 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-20867623

RESUMO

The satellite-borne experiment PAMELA has been used to make a new measurement of the cosmic-ray antiproton flux and the antiproton-to-proton flux ratio which extends previously published measurements down to 60 MeV and up to 180 GeV in kinetic energy. During 850 days of data acquisition approximately 1500 antiprotons were observed. The measurements are consistent with purely secondary production of antiprotons in the Galaxy. More precise secondary production models are required for a complete interpretation of the results.

17.
Int J Immunogenet ; 36(1): 73-8, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19207939

RESUMO

Chlamydia trachomatis serovar D produces large quantities of HSP60-1 during infections, which accumulate inside the host cell inducing autoimmunity. We compare the aminoacid sequences of the human HSP60 with the bacterial counterpart to better elucidate how CTHSP60 may simulate HSP60 from human origin during infection and may induce an autoimmune response. As a result of the comparison we suggest several possible epitopes of the CTHSP60, which may induce autoimmunity.


Assuntos
Autoimunidade , Chaperonina 60/química , Infecções por Chlamydia/imunologia , Chlamydia trachomatis/imunologia , Sequência de Aminoácidos , Sequência de Bases , Chaperonina 60/genética , Chaperonina 60/imunologia , Infecções por Chlamydia/genética , Infecções por Chlamydia/microbiologia , Chlamydia trachomatis/genética , Humanos , Dados de Sequência Molecular , Alinhamento de Sequência , Transcrição Gênica
18.
Eur J Histochem ; 52(4): 221-8, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19109096

RESUMO

Hsp60, a mitochondrial chaperonin highly conserved during evolution, has been found elevated in the cytosol of cancer cells, both in vivo and in vitro, but its role in determining apoptosis during oxidative stress (OS) has not yet been fully elucidated. The aim of the present work was to study the effects of OS on Hsp60 levels and its interactions with procaspase- 3 (p-C3) and p53 in tumor cells. NCI-H292 (mucoepidermoid carcinoma) cells were exposed to various concentrations of hydrogen peroxide (H2O2) for 24 hours. Cell viability was determined by Trypan blue and MTT assays. DNA damage was assessed by the Comet assay, and apoptosis was measured by the AnnexinV cytofluorimetric test. Exposure to increasing concentrations of H2O2 resulted in a reduction of cell viability, DNA damage, and early apoptotic phenomena. Hsp60, p-C3, p53, and p21 were assessed by Western blotting and immunocytochemistry before and after OS. Hsp60 and p-C3 were present before and after OS induction. Immunoprecipitation experiments showed an Hsp60/p-C3 complex before OS that persisted after it, while an Hsp60/p53 complex was not detected in either condition. The presence of wild type (wt) p53 was confirmed by RT-PCR, and p21 detection suggested p53 activation after OS. We postulate that, although OS may induce early apoptosis in NCI-H292 cells, Hsp60 exerts an anti-apoptotic effect in these cells and, by extension, it may do so in other cancer cells.


Assuntos
Carcinoma Mucoepidermoide/metabolismo , Caspase 3/metabolismo , Chaperonina 60/metabolismo , Neoplasias Pulmonares/metabolismo , Estresse Oxidativo , Apoptose/efeitos dos fármacos , Western Blotting , Carcinoma Mucoepidermoide/tratamento farmacológico , Carcinoma Mucoepidermoide/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ensaio Cometa , DNA/efeitos dos fármacos , Dano ao DNA , Formazans/metabolismo , Expressão Gênica/efeitos dos fármacos , Humanos , Peróxido de Hidrogênio/farmacologia , Imuno-Histoquímica , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Sais de Tetrazólio/metabolismo , Azul Tripano/metabolismo , Proteína Supressora de Tumor p53/biossíntese , Proteína Supressora de Tumor p53/genética
19.
APMIS ; 115(11): 1227-33, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18092954

RESUMO

Idiopathic dilated cardiomyopathy (IDCM) is a primary myocardial disease of unknown cause characterized by ventricular chamber enlargement with impaired contractile function. In familial forms of IDCM, mutations of genes coding for cytoskeletal proteins related to force transmission, such as dystrophin, cardiac actin, desmin, and delta-sarcoglycan, have been identified. Here, we report the data of a retrospective investigation carried out to evaluate the expression of atrial natriuretic peptide (ANP), CD34, troponin T and nestin in the myocardium of patients affected with IDCM. Formalin-fixed and paraffin-embedded consecutive tissue sections from the ventricular wall of 10 human normal hearts (NH) following forensic autopsy and 22 IDCM (living explanted hearts) were studied using primary monoclonal antibodies against ANP, CD34, troponin T and nestin by immunohistochemistry. Myocardial fibers were counted independently by three pathologists. Statistics included analysis of variance, log-rank test for Kaplan-Meier analysis, and kappa assessment for intra- and inter-observer variability. ANP and CD34 were significantly overexpressed in IDCM compared to NH (p<0.05). Conversely, troponin T and nestin expression levels did not show significant variation. Inter-observer kappa statistics showed a value of 0.87 and intra-observer kappa statistics a value of 0.98. Evaluation of the marker distribution in the myocardium of patients with IDCM CD34 expression curve was similar to that of troponin T (p<0.0001), although two groups could be identified. Patients with a difference of more than 20 myocardial fibers in expression of CD34 and troponin T had a somewhat less favorable survival although the difference was not significant. The analysis of cells positive for troponin T resulted in a similar number of cardiac fibers between NH and IDCM. This is in agreement with cardiac enlargement present in IDCM, which is due to ventricular dilatation rather than increased number of myocytes. Moreover, the expression of nestin, a marker of activation of myocardial precursors, did not change either, and this may confirm that there are no hyperplastic phenomena in the IDCM pathogenesis. The increase in ANP-positive cells in IDCM could be a consequence of neurohormonal activation due to a decline in the impaired myocyte contractility. Furthermore, since it was already shown that ANP could be important in the control of vascular remodeling, we postulated that the increase in CD34-positive cells might be functionally correlated with the increase in ANP production. Differential expression of CD34 and troponin T might be used in future studies to evaluate their prognostic value.


Assuntos
Antígenos CD34/metabolismo , Fator Natriurético Atrial/metabolismo , Cardiomiopatia Dilatada/patologia , Antígenos CD/metabolismo , Autopsia , Biomarcadores/análise , Ventrículos do Coração/patologia , Humanos , Imuno-Histoquímica , Proteínas de Filamentos Intermediários/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Nestina , Valores de Referência , Troponina T/metabolismo
20.
Eur J Histochem ; 51 Suppl 1: 101-3, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17703600

RESUMO

During embryonic development, a pool of cells may become a reserve of undifferentiated cells, the embryo-stolen adult stem cells (ESASC). ESASC may be responsible for adult tissue homeostasis, as well as disease development. Transdifferentiation is a sort of reprogramming of ESASC from one germ layer-derived tissue towards another. Transdifferentiation has been described to take place from mesoderm to ectodermal- or endodermal-derived tissues and viceversa but not from ectodermal- to endodermal-derived tissues. We hypothesise that two different populations of ESASC could exist, the first ecto/mesoblast-committed and the second endo/mesoblast-committed. If confirmed, this hypothesis could lead to new studies on the molecular mechanisms of cell differentiation and to a better understanding of the pathogenesis of a number of diseases.


Assuntos
Células-Tronco Adultas/citologia , Células-Tronco Adultas/fisiologia , Embrião de Mamíferos/citologia , Transplante de Células-Tronco , Ferimentos e Lesões/terapia , Adulto , Diferenciação Celular , Linhagem da Célula , Embrião de Mamíferos/fisiologia , Humanos , Mesoderma/citologia , Mesoderma/fisiologia
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