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1.
Nature ; 615(7954): 858-865, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36949201

RESUMO

Human society is dependent on nature1,2, but whether our ecological foundations are at risk remains unknown in the absence of systematic monitoring of species' populations3. Knowledge of species fluctuations is particularly inadequate in the marine realm4. Here we assess the population trends of 1,057 common shallow reef species from multiple phyla at 1,636 sites around Australia over the past decade. Most populations decreased over this period, including many tropical fishes, temperate invertebrates (particularly echinoderms) and southwestern Australian macroalgae, whereas coral populations remained relatively stable. Population declines typically followed heatwave years, when local water temperatures were more than 0.5 °C above temperatures in 2008. Following heatwaves5,6, species abundances generally tended to decline near warm range edges, and increase near cool range edges. More than 30% of shallow invertebrate species in cool latitudes exhibited high extinction risk, with rapidly declining populations trapped by deep ocean barriers, preventing poleward retreat as temperatures rise. Greater conservation effort is needed to safeguard temperate marine ecosystems, which are disproportionately threatened and include species with deep evolutionary roots. Fundamental among such efforts, and broader societal needs to efficiently adapt to interacting anthropogenic and natural pressures, is greatly expanded monitoring of species' population trends7,8.


Assuntos
Antozoários , Recifes de Corais , Calor Extremo , Peixes , Aquecimento Global , Invertebrados , Oceanos e Mares , Água do Mar , Alga Marinha , Animais , Austrália , Peixes/classificação , Invertebrados/classificação , Aquecimento Global/estatística & dados numéricos , Alga Marinha/classificação , Dinâmica Populacional , Densidade Demográfica , Água do Mar/análise , Extinção Biológica , Conservação dos Recursos Naturais/tendências , Equinodermos/classificação
2.
Reumatismo ; 76(1)2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38523582

RESUMO

OBJECTIVE: To report cross-sectionally serum levels of 25-hydroxyvitamin D [25(OH)D] in women living in Italy within 12 months from breast cancer (BC) diagnosis. METHODS: Baseline data were obtained from 394 women diagnosed with primary BC, enrolled from 2016 to 2019 in a lifestyle trial conducted in Italy. Subjects' characteristics were compared between two 25(OH)D concentrations (hypovitaminosis D<20 and ≥20 ng/mL) with the Chi-squared test or Fisher's exact test for small-expected counts. Using multiple logistic regression-adjusted models, we estimated odds ratios (ORs) of hypovitaminosis D with 95% confidence intervals (CIs) in the total sample and in the unsupplemented subgroup. RESULTS: Hypovitaminosis D was found in 39% of all subjects, 60% in unsupplemented subjects, and 10% in supplemented subjects. Increasing ORs of hypovitaminosis D were found with increasing body mass index, 25-30, >30, and ≥35 versus <25 kg/m2 (ORs: 2.50, 4.64, and 5.81, respectively, in the total cohort and ORs: 2.68, 5.38, and 7.08 in the unsupplemented); living in the most southern Italian region (OR 2.50, 95%CI 1.22-5.13); and with hypertriglyceridemia (OR 2.46; 95%CI 1.16-5.22), chemotherapy history (OR 1.86, 95%CI 1.03-3.38), and inversely with anti-estrogenic therapy (OR 0.43, 95%CI 0.24-0.75) in the total sample. CONCLUSIONS: Hypovitaminosis D in women recently diagnosed with BC and participating in a lifestyle trial in Italy was widespread and highest with obesity, hypertriglyceridemia, and chemotherapy use. Considering that hypovitaminosis D is a risk factor for lower efficacy of bone density treatments and possibly BC mortality, our results suggest the need to promptly address and treat vitamin D deficiency.


Assuntos
Neoplasias da Mama , Hipertrigliceridemia , Deficiência de Vitamina D , Vitamina D , Feminino , Humanos , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/complicações , Hipertrigliceridemia/complicações , Itália/epidemiologia , Estilo de Vida , Fatores de Risco , Vitamina D/análogos & derivados , Deficiência de Vitamina D/epidemiologia
3.
Brain Inj ; 36(9): 1196-1203, 2022 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-35996323

RESUMO

BACKGROUND: Physicians play a key role in ensuring athletes with concussion safely return to sport. Research has shown deficiencies in concussion education amongst physicians and medical students. However, studies have not previously been conducted in UK medical schools. OBJECTIVES: To assess students' concussion knowledge and learning in Scottish Medical Schools. DESIGN: A survey with 23 questions was distributed to Year 3-6 medical students studying in Scotland in October 2020. The survey included the following: (1) demographics, (2) concussion knowledge, e.g. 'What is the role of headgear in preventing concussion?' (3) concussion learning, 'In which part of the curriculum should concussion be taught?.' Frequencies of responses were calculated for each question. RESULTS: 200 students responded (response rate 8%). The average symptoms and management score were 87.3% and 31% respectively. 15% of participants knew that headgear has no role in preventing concussions and one participant identified the minimum "return to sport" timeframes for adults and children. 15% had learnt about concussion at medical school with 92.5% interested in receiving concussion teaching at medical school. CONCLUSION: Knowledge gaps exist in managing and preventing sports-related concussion. There is a discrepancy between levels of concussion teaching and the desire and importance placed on concussion education.


Assuntos
Traumatismos em Atletas , Concussão Encefálica , Esportes , Estudantes de Medicina , Adulto , Atletas , Traumatismos em Atletas/diagnóstico , Concussão Encefálica/diagnóstico , Criança , Humanos
4.
Br J Sports Med ; 55(6): 319-326, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33115706

RESUMO

OBJECTIVE: To scope the relationships between rugby union, and health and well-being. DESIGN: Scoping review. DATA SOURCES: Published and unpublished reports of any age, identified by searching electronic databases, platforms and reference lists. METHODS: A three-step search strategy identified relevant published primary, secondary studies and grey literature, which were screened using a priori inclusion criteria. Data were extracted using a standardised tool, to form (1) a numerical analysis and (2) a thematic summary. RESULTS AND DISCUSSION: 6658 records were identified, and 198 studies met the inclusion criteria. All forms of rugby union can provide health-enhancing physical activity (PA). 'Non-contact' and wheelchair rugby in particular provide a wide range of physical and mental health and well-being benefits. The evidence is either mixed or unclear in relation to 'contact' rugby union and its effects on a range of physical health domains. Injury and concussion incidence rates are high for contact rugby union relative to other sports. CONCLUSIONS: A wide range of stakeholders as well as existing and potential participants can use this information to make a more informed decision about participating in and promoting rugby union as a health-enhancing activity. Industry and policy-makers can use this review to inform policies and strategies that look to increase participation rates and use rugby union as a vehicle to contribute positively to population health. Further research understanding rugby union's contribution to PA as well as to muscle-strengthening and balance is indicated, as well as research examining more health and well-being outcomes across more diverse cohorts.


Assuntos
Futebol Americano/fisiologia , Futebol Americano/psicologia , Traumatismos em Atletas/epidemiologia , Lesões Encefálicas/epidemiologia , Futebol Americano/lesões , Humanos , Saúde Mental , Aptidão Física , Pesquisa , Esportes para Pessoas com Deficiência/fisiologia , Esportes para Pessoas com Deficiência/psicologia
5.
J Endocrinol Invest ; 41(8): 985-994, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29340973

RESUMO

PURPOSE: Thyrotropin (TSH) is the most accurate marker of thyroid dysfunction in the absence of pituitary or hypothalamic disease. Studies on TSH reference intervals (RIs) showed wide inter-individual variability and prompted an intense debate about the best estimation of TSH RIs. DESIGN: We performed a population study on TSH RIs, using current data stored in the laboratory information system (LIS), at the Hospital Department of Laboratory Medicine, Pordenone (Italy), historically an area of mild-moderate iodine deficiency with a relatively high goiter prevalence. METHODS: 136,650 individuals constituted the final sample. A TSH immunoassay was performed on fasting serum samples with the Dimension Vista 1500 analyzer (Siemens Healthineers). We adopted the Kairisto's procedure to analyze TSH data downloaded by the LIS, applying the indirect strategy for deriving RIs. RESULTS: TSH RIs of the entire population were 0.32-3.36 mIU/L with a distribution skewed towards higher values. RIs were 0.26-3.61 mIU/L for females, and 0.32-3.01 mIU/L for males. Unlike other studies, TSH median levels progressively decreased from 0-4 to 85-104 years in the overall population, both in male and in female subgroups, showing an inverse correlation between TSH and age in all groups. CONCLUSIONS: This study is the first to analyze a high percentage (40%) of individuals from an ethnically homogenous Caucasian population. The results obtained emphasize the opportunity to define the TSH RIs according to age, gender and race, in addition to assay methods, and provide further insight about the possible role of iodine status.


Assuntos
Biomarcadores/sangue , Doenças da Glândula Tireoide/diagnóstico , Doenças da Glândula Tireoide/epidemiologia , Glândula Tireoide/metabolismo , Tireotropina/sangue , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Prognóstico , Valores de Referência , Doenças da Glândula Tireoide/sangue , Adulto Jovem
7.
Bioscience ; 67(2): 134-146, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-28596615

RESUMO

Reporting progress against targets for international biodiversity agreements is hindered by a shortage of suitable biodiversity data. We describe a cost-effective system involving Reef Life Survey citizen scientists in the systematic collection of quantitative data covering multiple phyla that can underpin numerous marine biodiversity indicators at high spatial and temporal resolution. We then summarize the findings of a continental- and decadal-scale State of the Environment assessment for rocky and coral reefs based on indicators of ecosystem state relating to fishing, ocean warming, and invasive species and describing the distribution of threatened species. Fishing impacts are widespread, whereas substantial warming-related change affected some regions between 2005 and 2015. Invasive species are concentrated near harbors in southeastern Australia, and the threatened-species index is highest for the Great Australian Bight and Tasman Sea. Our approach can be applied globally to improve reporting against biodiversity targets and enhance public and policymakers' understanding of marine biodiversity trends.

10.
Opt Express ; 21(12): 14146-51, 2013 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-23787605

RESUMO

Polarization handling is a key requirement for the next generation of photonic integrated circuits (PICs). Integrated polarization beam splitters (PBS) are central elements for polarization management, but their use in PICs is hindered by poor fabrication tolerances. In this work we present a fully passive, highly fabrication tolerant polarization beam splitter, based on an asymmetrical Mach-Zehnder interferometer (MZI) with a Si/SiO(2) Periodic Layer Structure (PLS) on top of one of its arms. By engineering the birefringence of the PLS we are able to design the MZI arms so that sensitivities to the most critical fabrication errors are greatly reduced. Our PBS design tolerates waveguide width variations of 400nm maintaining a polarization extinction ratio better than 13dB in the complete C-Band.


Assuntos
Interferometria/instrumentação , Lentes , Refratometria/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento
11.
BMJ Open ; 11(1): e041037, 2021 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-33514574

RESUMO

INTRODUCTION: Rugby football (Union and League) provides physical activity (PA) with related physical and mental health benefits. However, as a collision sport, rugby research and media coverage predominantly focus on injuries in elite players while the overall impact on health and well-being remains unclear. This study aims to provide a greater understanding of the risks and benefits of rugby participation in a diverse sample of men and women, current and former rugby Union and League players from recreational to the elite level of play. We will explore: (1) joint-specific injuries and concussion; (2) joint pain and osteoarthritis (OA); (3) medical and mental health conditions; (4) PA and sedentary behaviour and (5) well-being (quality of life, flourishing and resilience). METHODS AND ANALYSIS: The Rugby Health and Well-being Study is designed in two phases: (1) a UK-wide cross-sectional survey and (2) cross-validation using health register data from Scotland. Participants will be at least 16 years old, current or former rugby players who have played rugby for at least one season. We will report standardised, level of play-, sex- and age-stratified prevalence of joint injury, concussion, medical conditions and PA. We will describe injury/concussion prevention expectations and protective equipment use. Rugby-related factors associated with injury, pain, OA, PA, health and well-being will be explored in regression models. We will compare joint pain intensity and duration, elements of pain perception and well-being between recreational and elite players and further investigate these associations in regression models while controlling for confounding variables. In the second phase, we will validate self-reported with health register data, and provide further information on healthcare use. ETHICS AND DISSEMINATION: The Yorkshire and the Humber-Leeds East Research Ethics Committee (REC reference: 19/HY/0377) has approved this study (IRAS project ID 269424). The results will be disseminated through scientific publications, conferences and social media.


Assuntos
Traumatismos em Atletas , Concussão Encefálica , Futebol Americano , Adolescente , Traumatismos em Atletas/epidemiologia , Concussão Encefálica/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Qualidade de Vida , Escócia , Reino Unido/epidemiologia
12.
Pathol Oncol Res ; 26(4): 2459-2467, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32564263

RESUMO

Undifferentiated Nasopharyngeal Carcinoma (UNPC) is associated with Epstein-Barr Virus (EBV) and characterized by an abundant immune infiltrate potentially influencing the prognosis. Thus, we retrospectively assessed the significance of immunosuppression in the UNPC microenvironment as prognostic biomarker of treatment failure in a non-endemic area, and monitored the variation of systemic EBV-specific immunity before and after chemoradiotherapy (CRT). DNA and RNA were extracted from diagnostic biopsies obtained by tumor and adjacent mucosa from 63 consecutive EBV+ UNPC patients who underwent radical CRT. Among these patients 11 relapsed within 2 years. The expression of the EBV-derived UNPC-specific BARF1 gene and several immune-related genes was monitored through quantitative RT-PCR and methylation-specific PCR analyses. Peripheral T cell responses against EBV and BARF1 were measured in 14 patients (7 relapses) through IFN-γ ELISPOT assay. We found significantly higher expression levels of BARF1, CD8, IFN-γ, IDO, PD-L1, and PD-1 in UNPC samples compared to healthy tissues. CD8 expression was significantly reduced in both tumor and healthy tissues in UNPC patients who relapsed within two years. We observed a hypomethylated FOXP3 intron 1 exclusively in relapsed UNPC patients. Finally, we noticed a significant decrease in EBV- and BARF1-specific T-cells after CRT only in relapsing patients. Our data suggest that a high level of immunosuppression (low CD8, hypomethylated FoxP3) in UNPC microenvironment may predict treatment failure and may allow an early identification of patients who could benefit from the addition of immune modulating strategies to improve first line CRT.


Assuntos
Antígenos CD8/imunologia , Resistencia a Medicamentos Antineoplásicos/imunologia , Fatores de Transcrição Forkhead/imunologia , Carcinoma Nasofaríngeo/imunologia , Neoplasias Nasofaríngeas/imunologia , Tolerância a Radiação/imunologia , Adolescente , Adulto , Idoso , Quimiorradioterapia/métodos , Metilação de DNA , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/imunologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo/terapia , Neoplasias Nasofaríngeas/terapia , Valor Preditivo dos Testes , Estudos Retrospectivos , Microambiente Tumoral/imunologia , Proteínas Virais/imunologia , Adulto Jovem
13.
Ann Oncol ; 20(12): 1936-42, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19567452

RESUMO

BACKGROUND: We evaluated efficacy and safety of early and short-term prophylaxis with acenocumarine or dalteparin in the prevention of non-occlusive or occlusive central vein catheter-related thrombosis (CVCrT). PATIENTS AND METHODS: Consecutive cancer patients scheduled for chemotherapy randomly received: acenocumarine 1 mg/day for 3 days before and 8 days after central vein catheter (CVC) insertion; dalteparin 5000 IU 2 h before and daily for 8 days after CVC insertion; no anticoagulant treatment (NT). All patients underwent venography on days 8 and 30, some of them on days 90, 150 and 210 after CVC. RESULTS: A total of 450 patients were randomized, 348 underwent at least two venography. Both acenocumarine and dalteparin reduced venography-detected CVCrT rate [21.9% acenocumarine versus 52.6% NT, odds ratio (OR) 0.3, P < 0.01; 40% dalteparin versus 52.6% NT, OR 0.6, P = 0.05]. Acenocumarine was more effective than dalteparin (OR 0.4, P = 0.01). The rate of occlusive CVCrT was not different in the three groups (0.9% acenocumarine, 3.3% dalteparin, 1.8% NT; P = 0.40). Most CVCrTs (95.6%) were observed on day 8 after CVC insertion and were non-occlusive. CONCLUSIONS: In this study of early and short-term prophylaxis, acenocumarine was more effective than dalteparin on non-occlusive and asymptomatic CVCrT events. The first days following CVC insertion represent the highest risk for CVCrT.


Assuntos
Acenocumarol/uso terapêutico , Anticoagulantes/uso terapêutico , Cateterismo Venoso Central/efeitos adversos , Dalteparina/uso terapêutico , Neoplasias/terapia , Flebografia , Trombose/prevenção & controle , Acenocumarol/administração & dosagem , Idoso , Anticoagulantes/administração & dosagem , Dalteparina/administração & dosagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/complicações , Trombose/complicações
14.
Int J Biol Markers ; 22(4): 307-11, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18161663

RESUMO

BACKGROUND: Bronchioloalveolar carcinoma (BAC) is a histological subtype of non-small cell lung cancer (NSCLC), particularly of adenocarcinoma. Given its multifocality and the poor activity of chemotherapy, there is no established treatment for BAC, although promising results have been achieved with inhibitors of the epidermal growth factor receptor (EGFR). No tumor marker has been validated in the diagnosis and follow-up of lung cancer, in particular to predict the outcome of treatment with EGFR inhibitors. PURPOSE: As CA 15-3 antigen serum levels are reported to be pathologically abnormal in adenocarcinoma of the lung, we chose this tumor marker to monitor treatment with EGFR inhibitors of patients affected by adenocarcinoma with BAC features or pure BAC. PATIENTS AND METHODS: We collected data from 26 consecutive Caucasian patients with BAC, mostly women and never smokers, who received EGFR inhibitors. RESULTS: We noticed that all patients with normal CA 15-3 serum levels at baseline (15/26, 57.7%) showed a response to EGFR inhibitors, whereas all patients with abnormal CA 15-3 serum levels (11/26, 42.3%) did not. CONCLUSION: Our data suggest that CA 15-3 levels might be a predictive factor for the response to EGFR inhibitors in patients with BAC.


Assuntos
Adenocarcinoma Bronquioloalveolar/tratamento farmacológico , Adenocarcinoma Bronquioloalveolar/metabolismo , Biomarcadores Tumorais , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Receptores ErbB/antagonistas & inibidores , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/metabolismo , Mucina-1/biossíntese , Mucina-1/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Feminino , Predisposição Genética para Doença , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Masculino , Pessoa de Meia-Idade
15.
Auto Immun Highlights ; 8(1): 8, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28631225

RESUMO

PURPOSE: In the last two decades, thyroglobulin autoantibodies (TgAb) measurement has progressively switched from marker of thyroid autoimmunity to test associated with thyroglobulin (Tg) to verify the presence or absence of TgAb interference in the follow-up of patients with differentiated thyroid cancer. Of note, TgAb measurement is cumbersome: despite standardization against the International Reference Preparation MRC 65/93, several studies demonstrated high inter-method variability and wide variation in limits of detection and in reference intervals. Taking into account the above considerations, the main aim of the present study was the determination of TgAb upper reference limit (URL), according to the National Academy of Clinical Biochemistry guidelines, through the comparison of eleven commercial automated immunoassay platforms. METHODS: The sera of 120 healthy males, selected from a population survey in the province of Verona, Italy, were tested for TgAb concentration using eleven IMA applied on as many automated analyzers: AIA-2000 (AIA) and AIA-CL2400 (CL2), Tosoh Bioscience; Architect (ARC), Abbott Diagnostics; Advia Centaur XP (CEN) and Immulite 2000 XPi (IMM), Siemens Healthineers; Cobas 6000 (COB), Roche Diagnostics; Kryptor (KRY), Thermo Fisher Scientific BRAHMS, Liaison XL (LIA), Diasorin; Lumipulse G (LUM), Fujirebio; Maglumi 2000 Plus (MAG), Snibe and Phadia 250 (PHA), Phadia AB, Thermo Fisher Scientific. All assays were performed according to manufacturers' instructions in six different laboratories in Friuli-Venezia Giulia and Veneto regions of Italy [Lab 1 (AIA), Lab 2 (CL2), Lab 3 (ARC, COB and LUM), Lab 4 (CEN, IMM, KRY and MAG), Lab 5 (LIA) and Lab 6 (PHA)]. Since TgAb values were not normally distributed, the experimental URL (e-URL) was established at 97.5 percentile according to the non-parametric method. RESULTS: TgAb e-URLs showed a significant inter-method variability. Considering the same method, e-URL was much lower than that suggested by manufacturers (m-URL), except for ARC and MAG. Correlation and linear regression were unsatisfactory. Consequently, the agreement between methods was poor, with significant bias in Bland-Altman plot. CONCLUSIONS: Despite the efforts for harmonization, TgAb methods cannot be used interchangeably. Therefore, additional effort is required to improve analytical performance taking into consideration approved protocols and guidelines. Moreover, TgAb URL should be used with caution in the management of differentiated thyroid carcinoma patients since the presence and/or the degree of TgAb interference in Tg measurement has not yet been well defined.

16.
Circulation ; 102(11): 1290-5, 2000 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-10982545

RESUMO

BACKGROUND: Excessive bleeding may complicate congenital cardiac defects. To explain the pathogenesis of this abnormality, we evaluated selected parameters of primary hemostasis in patients with aortic valve stenosis before and after corrective surgery. METHODS AND RESULTS: We examined shear-induced platelet aggregation with the filter aggregometer test and von Willebrand factor (vWF) structure by evaluating the multimeric distribution and extent of subunit proteolysis. The platelet count was reduced before corrective surgery, and shear-induced platelet aggregation was impaired. Moreover, vWF multimers of higher molecular mass were decreased, and proteolytic subunit fragments were increased. After correction of the cardiac defect, all of these parameters returned to normal. CONCLUSIONS: Alterations of vWF and platelet function may contribute to the bleeding diathesis in patients with aortic valve stenosis. Improvement after corrective surgery suggests that the passage of blood through a stenosed aortic valve may result in shear forces that induce vWF interaction with platelets in the circulation and, in turn, trigger platelet clearance, vWF degradation, and the impairment of primary hemostasis.


Assuntos
Estenose da Valva Aórtica/sangue , Estenose da Valva Aórtica/metabolismo , Agregação Plaquetária , Fator de von Willebrand/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Estenose da Valva Aórtica/congênito , Estenose da Valva Aórtica/cirurgia , Feminino , Hemostasia , Humanos , Técnicas In Vitro , Masculino , Pessoa de Meia-Idade , Estresse Mecânico
17.
AIDS ; 8(6): 747-52, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8086131

RESUMO

OBJECTIVES: Since human liver endothelial cells allow HIV-1 multiplication in vitro, we investigated whether HIV induced functional alterations in these cells in primary culture. DESIGN: Direct evidence of the replication of HIV in endothelial cells is sparse, but clotting abnormalities and thrombi, which suggest the existence of an endothelial dysfunction, have been observed in HIV-infected patients. We therefore studied the storage and release of endothelial-specific factors in primary cultures of liver endothelial cells infected with HIV, as well as their cytoskeleton, pinocytic and phagocytic properties. METHODS: Intracellular storage of von Willebrand's factor (vWF) was determined by immunofluorescence and computer image analysis. Excretion of vWF, protein S and endothelin-1 was measured using an enzyme-linked immunosorbent assay and radioimmunoassay. Cytoskeletal constituents were studied by light microscopy. The pinocytosis of acetylated low-density lipoproteins and the phagocytosis of latex beads were analysed under light and electron microscopy. RESULTS: The synthesis of vWF is markedly decreased in HIV-infected liver endothelial cells, as is the excretion of endothelin-1. In contrast, the excretion of protein S remains unaffected and the cytoskeletal network appears to be unaltered. Pinocytosis and phagocytosis are preserved. CONCLUSIONS: HIV infection triggers non-lethal functional alterations in cultured human liver sinusoidal endothelial cells, with a selective impairment in the storage and/or the excretion of endothelial-specific factors such as vWF. This functional modulation could play a role in the pathophysiology of HIV-induced disease.


Assuntos
HIV-1/fisiologia , Fígado/microbiologia , Células Cultivadas , Endotélio/microbiologia , Endotélio/fisiopatologia , Humanos , Lipoproteínas LDL/metabolismo , Fígado/fisiopatologia , Pinocitose , Replicação Viral , Fator de von Willebrand/metabolismo
18.
Microbes Infect ; 3(3): 193-202, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11358713

RESUMO

It is currently unclear whether the hepatocellular damage in chronic hepatitis C virus (HCV) infection is produced through the intrahepatic action of the anti-HCV immune response or through a direct cytopathic effect. In order to investigate the features of HCV replication (morphogenesis and cytopathic effect), we studied the infection of a permissive lymphocytic B cell line, Daudi cells, which were infected with sera of HCV-positive patients, and were examined after various time points under electron microscope. Viral genomic RNA was detected by in situ hybridization, and apoptosis with the terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) method. The amount of viral genomic RNA was observed to increase during infection. HCV replicated rapidly, since characteristics of viral morphogenesis resembling those of yellow fever virus in a hepatoma cell line could be found 2 days after infection. These included the following: a) several viral particles identical in size (about 42 nm) and structure (a spherical 30-nm-sized electron-dense nucleocapsid surrounded by a membrane) to yellow fever virus were present in the cytoplasm of cells displaying already typical signs of the early stage of apoptosis; b) numerous membrane-bound organelles and in particular the endoplasmic reticulum and vacuoles were observed; c) proliferation of membranes was apparent; and d) intracytoplasmic electron-dense inclusion bodies which have been demonstrated to correspond to nucleocapsids for other flaviviruses were detected. Several cells presented electron-dense areas in the endoplasmic reticulum displaying 30-nm circular structures lying among an amorphous material. Striking cytopathic features with ballooning, extremely enlarged vacuoles and signs of apoptosis were found in cells often containing sequestered aggregates of virus-like particles. By in situ hybridization we found that such enlarged cells contained HCV RNA. Our results thus indicate that the ultrastructural features of HCV viral particles and their morphogenesis resemble that of yellow fever virus and dengue virus. In Daudi cells, HCV infection seems to rapidly trigger apoptotic cell death, and efficient release of viral particles does not seem to take place.


Assuntos
Hepacivirus/ultraestrutura , Células Tumorais Cultivadas/ultraestrutura , Células Tumorais Cultivadas/virologia , Apoptose , Efeito Citopatogênico Viral , Hepacivirus/genética , Hepacivirus/isolamento & purificação , Humanos , Hibridização In Situ , Microscopia Eletrônica , RNA Viral/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas/patologia
19.
J Immunol Methods ; 178(1): 121-30, 1995 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-7829861

RESUMO

Several 'capture' assays are currently employed to identify specific platelet antibodies, but all require the use of murine monoclonal antibodies (MoAbs) against the antigen of interest. We have developed a new antigen capture assay for the detection of platelet reactive antibodies, based on platelet surface sialoglycoprotein labelling with biotin hydrazide, and a following immobilization of the biotinylated platelet proteins to microtiter wells that had been coated with streptavidin. The resulting solid phase can then be used in a simple ELISA to detect serum and platelet associated antibodies. We describe here two versions of this biotin-avidin immobilization of platelet glycoproteins (BAIPG) assay. In BAIPG assay type I, the test sera are directly incubated in microtiter wells previously coated with streptavidin plus biotinylated platelet proteins. The BAIPG type II procedure involves the incubation of sera with biotinylated platelets before platelet solubilization, and, after platelet lysis, the immobilization of the immune complexes to streptavidin-coated wells. In both cases, the bound antibodies are determined by alkaline phosphatase conjugated anti-human IgG. Using BAIPG type I, positive results were obtained in 7/33 patients with idiopathic thrombocytopenic purpura (ITP), 1/10 patients with secondary immune thrombocytopenia (SIT) and 4/17 with non-immune thrombocytopenia (NIT). The BAIPG type II test was positive in 13 out of 33 patients with ITP, in six out of ten patients with SIT, and in three out of the 17 patients with NIT. A comparison between BAIPG and monoclonal antibody immobilization of platelet antigens (MAIPA) assays showed a high degree of correlation between the two methods. These results suggest that the BAIPG assay is a valuable new tool for the detection of anti-platelet antibodies.


Assuntos
Autoanticorpos/sangue , Plaquetas/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Glicoproteínas de Membrana/imunologia , Trombocitopenia/imunologia , Avidina , Biotina , Membrana Celular/imunologia , Humanos
20.
Virus Res ; 1(7): 557-63, 1984 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-6099940

RESUMO

Damage to the Kupffer and endothelial cells of the liver sinusoids induced by the administration of sublethal doses of frog virus 3 (FV 3) renders A/J mice which are genetically resistant to mouse hepatitis virus type 3 (MHV 3) highly susceptible to this virus. Liver histopathology of these animals revealed typical necrotic foci containing MHV 3-specific antigens. FV 3-pretreated mice, after MHV 3 infection, showed higher levels of serum transaminase (GPT) than controls, and MHV 3 replicated more rapidly and to higher titres. Our results bear out the important role of the liver sinusoidal lining in protecting against hepatocyte infection and its direct involvement in the resistance of A/J mice to MHV 3 infection.


Assuntos
Hepatite Viral Animal/fisiopatologia , Células de Kupffer/fisiologia , Fígado/fisiologia , Vírus da Hepatite Murina/patogenicidade , Viroses/complicações , Animais , Suscetibilidade a Doenças , Endotélio/fisiologia , Hepatite Viral Animal/etiologia , Iridoviridae/fisiologia , Camundongos , Camundongos Endogâmicos A , Viremia/fisiopatologia
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