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1.
Thromb Res ; 231: 84-90, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37832365

RESUMO

INTRODUCTION: The incidence of splanchnic vein thrombosis (SVT) in cancer patients has increased in recent years and its real clinical significance and management can be challenging. This study aimed to describe the clinical presentation and short-term outcomes of patients with cancer-associated SVT. MATERIAL AND METHODS: This was a retrospective observational study of consecutive patients with cancer-associated SVT diagnosed during the period 2015-2020. The primary objective was to describe the clinical presentation of SVT. Patients were clinically classified into two groups based on the presence of symptoms on SVT diagnosis. The main outcomes were overall and SVT-related mortality, major and non-major bleeding rates, and the thrombosis recurrence rate in the first 30 days of follow-up. RESULTS: This study enrolled 203 patients. Intra-abdominal tumors (76 %) and metastatic disease (68 %) predominated. A total of 79 (39 %) patients without symptoms were diagnosed with SVT during a scheduled radiological test and were classified as "asymptomatic", while 124 (61 %) patients presented some potential SVT symptoms and were considered as "symptomatic". Although the 30-day outcomes showed no significant differences between the two groups, mortality in the asymptomatic group was slightly lower compared to the symptomatic group (3 % vs. 10 %, p = 0.085). CONCLUSIONS: Almost 40 % of cases of cancer-associated SVT are asymptomatic. There were no significant differences in short-term outcomes between the symptomatic and asymptomatic patients. More studies are required to better define long-term management and outcomes in these patients.


Assuntos
Neoplasias , Trombose , Trombose Venosa , Humanos , Circulação Esplâncnica , Trombose Venosa/complicações , Trombose Venosa/diagnóstico , Trombose/complicações , Estudos Retrospectivos , Neoplasias/complicações , Anticoagulantes/efeitos adversos
2.
Cell Tissue Res ; 390(2): 207-227, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36083358

RESUMO

In echinoderms, the coelomic epithelium (CE) is reportedly the source of new circulating cells (coelomocytes) as well as the provider of molecular factors such as immunity-related molecules. However, its overall functions have been scarcely studied in detail. In this work, we used an integrated approach based on both microscopy (light and electron) and proteomic analyses to investigate the arm CE in the starfish Marthasterias glacialis during different physiological conditions (i.e., non-regenerating and/or regenerating). Our results show that CE cells share both ultrastructural and proteomic features with circulating coelomocytes (echinoderm immune cells). Additionally, microscopy and proteomic analyses indicate that CE cells are actively involved in protein synthesis and processing, and membrane trafficking processes such as phagocytosis (particularly of myocytes) and massive secretion phenomena. The latter might provide molecules (e.g., immune factors) and fluids for proper arm growth/regrowth. No stem cell marker was identified and no pre-existing stem cell was observed within the CE. Rather, during regeneration, CE cells undergo dedifferentiation and epithelial-mesenchymal transition to deliver progenitor cells for tissue replacement. Overall, our work underlines that echinoderm CE is not a "simple epithelial lining" and that instead it plays multiple functions which span from immunity-related roles as well as being a source of regeneration-competent cells for arm growth/regrowth.


Assuntos
Equinodermos , Proteômica , Animais , Epitélio/ultraestrutura , Estrelas-do-Mar , Células Epiteliais
3.
J R Soc Interface ; 19(193): 20220226, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35946165

RESUMO

Repeated polygonal patterns are pervasive in natural forms and structures. These patterns provide inherent structural stability while optimizing strength-per-weight and minimizing construction costs. In echinoids (sea urchins), a visible regularity can be found in the endoskeleton, consisting of a lightweight and resistant micro-trabecular meshwork (stereom). This foam-like structure follows an intrinsic geometrical pattern that has never been investigated. This study aims to analyse and describe it by focusing on the boss of tubercles-spine attachment sites subject to strong mechanical stresses-in the common sea urchin Paracentrotus lividus. The boss microstructure was identified as a Voronoi construction characterized by 82% concordance to the computed Voronoi models, a prevalence of hexagonal polygons, and a regularly organized seed distribution. This pattern is interpreted as an evolutionary solution for the construction of the echinoid skeleton using a lightweight microstructural design that optimizes the trabecular arrangement, maximizes the structural strength and minimizes the metabolic costs of secreting calcitic stereom. Hence, this identification is particularly valuable to improve the understanding of the mechanical function of the stereom as well as to effectively model and reconstruct similar structures in view of future applications in biomimetic technologies and designs.


Assuntos
Paracentrotus , Animais , Esqueleto , Coluna Vertebral , Estresse Mecânico
4.
Front Cardiovasc Med ; 9: 897244, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35722114

RESUMO

In addition to long-term regulation of blood pressure (BP), in the kidney resides the initial trigger for hypertension development due to an altered capacity to excrete sodium and water. Betaine is one of the major organic osmolytes, and its betaine/gamma-aminobutyric acid transporter (BGT-1) expression in the renal medulla relates to interstitial tonicity and urinary osmolality and volume. This study investigated altered water and sodium balance as well as changes in antidiuretic hormone (ADH) activity in female spontaneously hypertensive (SHR) and normotensive Wistar Kyoto (WKY) rats from their 3-5 weeks of age (prehypertensive phase) to SHR's 28-30 weeks of age (established hypertension-organ damage). Young prehypertensive SHRs showed a reduced daily urine output, an elevated urine osmolarity, and higher immunostaining of tubule BGT-1, alpha-1-Na-K ATPase in the outer medulla vs. age-matched WKY. ADH circulating levels were not different between young prehypertensive SHR and WKY, but the urine aquaporin2 (AQP2)/creatinine ratio and labeling of AQP2 in the collecting duct were increased. At 28-30 weeks, hypertensive SHR with moderate renal failure did not show any difference in urinary osmolarity, urine AQP2/creatinine ratio, tubule BGT-1, and alpha-1-Na-K ATPase as compared with WKY. These results suggest an increased sensitivity to ADH in prehypertensive female SHR. On this basis, a second series of experiments were set to study the role of ADH V1 and V2 receptors in the development of hypertension, and a group of female prehypertensive SHRs were treated from the 25th to 49th day of age with either V1 (OPC21268) or V2 (OPC 41061) receptor antagonists to evaluate the BP time course. OPC 41061-treated SHRs had a delayed development of hypertension for 5 weeks without effect in OPC 21268-treated SHRs. In prehypertensive female SHR, an increased renal ADH sensitivity is crucial for the development of hypertension by favoring a positive water balance. Early treatment with selective V2 antagonism delays future hypertension development in young SHRs.

5.
R Soc Open Sci ; 9(5): 211972, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35592761

RESUMO

In the field of structural engineering, lightweight and resistant shell structures can be designed by efficiently integrating and optimizing form, structure and function to achieve the capability to sustain a variety of loading conditions with a reduced use of resources. Interestingly, a limitless variety of high-performance shell structures can be found in nature. Their study can lead to the acquisition of new functional solutions that can be employed to design innovative bioinspired constructions. In this framework, the present study aimed to illustrate the main results obtained in the mechanical analysis of the echinoid test in the common sea urchin Paracentrotus lividus (Lamarck, 1816) and to employ its principles to design lightweight shell structures. For this purpose, visual survey, photogrammetry, three-dimensional modelling, three-point bending tests and finite-element modelling were used to interpret the mechanical behaviour of the tessellated structure that characterize the echinoid test. The results achieved demonstrated that this structural topology, consisting of rigid plates joined by flexible sutures, allows for a significant reduction of bending moments. This strategy was generalized and applied to design both free-form and form-found shell structures for architecture exhibiting improved structural efficiency.

6.
Sci Rep ; 11(1): 13733, 2021 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-34215803

RESUMO

To determine the proportion of patients with COVID-19 who were readmitted to the hospital and the most common causes and the factors associated with readmission. Multicenter nationwide cohort study in Spain. Patients included in the study were admitted to 147 hospitals from March 1 to April 30, 2020. Readmission was defined as a new hospital admission during the 30 days after discharge. Emergency department visits after discharge were not considered readmission. During the study period 8392 patients were admitted to hospitals participating in the SEMI-COVID-19 network. 298 patients (4.2%) out of 7137 patients were readmitted after being discharged. 1541 (17.7%) died during the index admission and 35 died during hospital readmission (11.7%, p = 0.007). The median time from discharge to readmission was 7 days (IQR 3-15 days). The most frequent causes of hospital readmission were worsening of previous pneumonia (54%), bacterial infection (13%), venous thromboembolism (5%), and heart failure (5%). Age [odds ratio (OR): 1.02; 95% confident interval (95% CI): 1.01-1.03], age-adjusted Charlson comorbidity index score (OR: 1.13; 95% CI: 1.06-1.21), chronic obstructive pulmonary disease (OR: 1.84; 95% CI: 1.26-2.69), asthma (OR: 1.52; 95% CI: 1.04-2.22), hemoglobin level at admission (OR: 0.92; 95% CI: 0.86-0.99), ground-glass opacification at admission (OR: 0.86; 95% CI:0.76-0.98) and glucocorticoid treatment (OR: 1.29; 95% CI: 1.00-1.66) were independently associated with hospital readmission. The rate of readmission after hospital discharge for COVID-19 was low. Advanced age and comorbidity were associated with increased risk of readmission.


Assuntos
COVID-19/terapia , Readmissão do Paciente , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , COVID-19/complicações , COVID-19/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Alta do Paciente , Estudos Retrospectivos , Fatores de Risco , SARS-CoV-2/isolamento & purificação
7.
Bioinspir Biomim ; 16(1)2020 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-32927446

RESUMO

The endoskeleton of echinoderms (Deuterostomia: Echinodermata) is of mesodermal origin and consists of cells, organic components, as well as an inorganic mineral matrix. The echinoderm skeleton forms a complex lattice-system, which represents a model structure for naturally inspired engineering in terms of construction, mechanical behaviour and functional design. The sea urchin (Echinodermata: Echinoidea) endoskeleton consists of three main structural components: test, dental apparatus and accessory appendages. Although, all parts of the echinoid skeleton consist of the same basic material, their microstructure displays a great potential in meeting several mechanical needs according to a direct and clear structure-function relationship. This versatility has allowed the echinoid skeleton to adapt to different activities such as structural support, defence, feeding, burrowing and cleaning. Although, constrained by energy and resource efficiency, many of the structures found in the echinoid skeleton are optimized in terms of functional performances. Therefore, these structures can be used as role models for bio-inspired solutions in various industrial sectors such as building constructions, robotics, biomedical and material engineering. The present review provides an overview of previous mechanical and biomimetic research on the echinoid endoskeleton, describing the current state of knowledge and providing a reference for future studies.


Assuntos
Biomimética , Equinodermos , Animais , Ouriços-do-Mar
8.
J Hazard Mater ; 398: 122848, 2020 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-32474317

RESUMO

The information concerning the toxicity of sinking microplastics (MPs) on benthic marine animals, particularly benthic grazers, is still scant. No study focused on biological weathering of sinked MPs operated by benthic organisms. This study aims at investigating the ingestion and the effects induced by 7-days dietary exposure to environmentally relevant amount (8, 80 and 800 particles/g of food) of irregular shaped and sized (diameter 12.6-1,065 µm; mean diameter 316 ± 12 µm) polyethylene terephthalate microplastics (PET-MPs) on a common marine benthic grazer, the sea urchin Paracentrotus lividus. Adverse effects were investigated on digestive tract at biochemical (oxidative stress biomarkers) and tissue level (histopathological analyses). Potential alteration of MP structure/surface and PET macromolecules due to the ingestion of PET-MPs within the sea urchin digestive tract were investigated. Results showed that PET-MPs were efficiently egested by sea urchins without producing histological alterations on digestive tract tissues, only inducing a slight modulation of oxidative status. Sea urchin grazing activity and the related transit of PET-MPs within animal digestive tract slightly affected MP structure and PET composition. These findings suggest that PET-MPs might represent an hazard for benthic grazer organisms, which can partially contribute to the degradation of PET in marine ecosystems.


Assuntos
Microplásticos , Poluentes Químicos da Água , Animais , Ecossistema , Plásticos/toxicidade , Polietileno , Polietilenotereftalatos/toxicidade , Água , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
9.
Cell Tissue Res ; 381(3): 411-426, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32350640

RESUMO

Extracellular matrix (ECM) plays a dynamic role during tissue development and re-growth. Body part regeneration efficiency relies also on effective ECM remodelling and deposition. Among invertebrates, echinoderms are well known for their striking regenerative abilities since they can rapidly regenerate functioning complex structures. To gather insights on the involvement of ECM during arm regeneration, the brittle star Amphiura filiformis was chosen as experimental model. Eight ECM genes were identified and cloned, and their spatio-temporal and quantitative expression patterns were analysed by means of whole mount in situ hybridisation and quantitative PCR on early and advanced regenerative stages. Our results show that almost none of the selected ECM genes are expressed at early stages of regeneration, suggesting a delay in their activation that may be responsible for the high regeneration efficiency of these animals, as described for other echinoderms and in contrast to most vertebrates. Moreover, at advanced stages, these genes are spatially and temporally differentially expressed, suggesting that the molecular regulation of ECM deposition/remodelling varies throughout the regenerative process. Phylogenetic analyses of the identified collagen-like genes reveal complex evolutionary dynamics with many rounds of duplications and losses and pinpointed their homologues in selected vertebrates. The study of other ECM genes will allow a better understanding of ECM contribution to brittle star arm regeneration.


Assuntos
Equinodermos/genética , Matriz Extracelular/genética , Extremidades/patologia , Hibridização In Situ/métodos , Animais
10.
J. Phys. Educ. (Maringá) ; 31: e3136, 2020. tab
Artigo em Inglês | LILACS | ID: biblio-1134741

RESUMO

ABSTRACT This study ivestigated the association between noise and impaired sleep quality in 150 physical education instructors, in bodybuilding gyms. Two questionnaires were applied: evaluation of subjective sleep quality and analysis of explanatory variables. Noise exposure was analyzed. For the data analysis, was used the technique of non-conditional logistic regression, to obtain the values of the adjusted odds ratios (OR) of the significant variables. Two proper adjustment models stood out. The first model presented the significant variables: incorrect performance of the meals (OR = 2.58, 95% CI 1.08 to 6.02); skin color - black ou brown (OR = 0.53, 95% CI 0.25 to 1.12) and exposure to noise level above or equal to 80 dB(A) (OR = 1.90; 95% CI 0.87 to 4.12). The second model presented the significant variables: incorrect performance of the meals (OR = 2.35, 95% CI 0.1 to 5.56); exposure level standardized above or equal to 80 dB(A) (OR = 2.03, 95% CI 0.92 to 4.47) and use 0of drugs for depression/anxiety (OR = 0.26; 95% CI 0.53 to 1.33). This research identified the variables that were significantly associated with impaired sleep quality, as exposure to noise, contributing to the adoption of preventive measures.


RESUMO Este estudo investigou a associação entre ruído e qualidade prejudicada do sono em 150 instrutores de educação física, em academias de musculação. Dois questionários foram aplicados: avaliação da qualidade subjetiva do sono e sobre variáveis explanatórias. A exposição ao ruído foi avaliada. Para a análise dos dados, utilizou-se a técnica de regressão logística não-condicional, para obter os valores das Razões de Chances (RC) das variáveis significativas. Dois modelos finais se destacaram. O primeiro apresentou as variáveis significativas: realização incorreta das refeições (RC = 2,58, IC 95% 1,08 a 6,02); cor da pele - preta ou parda (RC = 0,53; IC 95% 0,25 a 1,12) e exposição ao ruído acima ou igual a 80 dB(A) (RC = 1,90; IC95% 0,87 a 4,12). O segundo modelo apresentou as variáveis significativas: realização incorreta das refeições (RC = 2,35, IC 95% 0,1 a 5,56); nível de exposição padronizado acima ou igual a 80 dB (A) (RC = 2,03, IC 95% 0,92 a 4,47) e uso de medicamentos para depressão/ansiedade (RC = 0,26; IC95% 0,53 a 1,33). Esta pesquisa identificou as variáveis que se associaram significativamente com a qualidade do sono prejudicada, como a exposição ao ruído, contribuindo para a adoção de medidas preventivas.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Sono/efeitos dos fármacos , Ruído/efeitos adversos , Ansiedade/prevenção & controle , Educação Física e Treinamento/estatística & dados numéricos , Preparações Farmacêuticas , Depressão/prevenção & controle , Uso de Medicamentos , Academias e Institutos/organização & administração , Docentes/educação , Refeições
11.
Results Probl Cell Differ ; 65: 285-320, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30083925

RESUMO

Reparative regeneration is defined as the replacement of lost adult body parts and is a phenomenon widespread yet highly variable among animals. This raises the question of which key cellular and molecular mechanisms have to be implemented in order to efficiently and correctly replace entire body parts in any animal. To address this question, different studies using an integrated cellular and functional genomic approach to study regeneration in stellate echinoderms (crinoids, asteroids and ophiuroids) had been carried out over the last few years. The phylum Echinodermata is recognized for the striking regeneration potential shown by the members of its different clades. Indeed, stellate echinoderms are considered among the most useful and tractable experimental models for carrying comprehensive studies focused on ecological, developmental and evolutionary aspects. Moreover, most of them are tractable in the laboratory and, thus, should allow us to understand the underlying mechanisms, cellular and molecular, which are involved. Here, a comprehensive analysis of the cellular/histological components of the regenerative process in crinoids, asteroids and ophiuroids is described and compared. However, though this knowledge provided us with some clear insights into the global distribution of cell types at different times, it did not explain us how the recruited cells are specified (and from which precursors) over time and where are they located in the animal. The precise answer to these queries needs the incorporation of molecular approaches, both descriptive and functional. Yet, the molecular studies in stellate echinoderms are still limited to characterization of some gene families and protein factors involved in arm regeneration but, at present, have not shed light on most of the basic mechanisms. In this context, further studies are needed specifically to understand the role of regulatory factors and their spatio-temporal deployment in the growing arms. A focus on developing functional tools over the next few years should be of fundamental importance.


Assuntos
Equinodermos/classificação , Equinodermos/fisiologia , Regeneração , Animais , Evolução Biológica
12.
Dev Biol ; 433(2): 297-309, 2018 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-29291979

RESUMO

Regeneration is a post-embryonic developmental process that ensures complete morphological and functional restoration of lost body parts. The repair phase is a key step for the effectiveness of the subsequent regenerative process: in vertebrates, efficient re-epithelialisation, rapid inflammatory/immune response and post-injury tissue remodelling are fundamental aspects for the success of this phase, their impairment leading to an inhibition or total prevention of regeneration. Among deuterostomes, echinoderms display a unique combination of striking regenerative abilities and diversity of useful experimental models, although still largely unexplored. Therefore, the brittle star Amphiura filiformis and the starfish Echinaster sepositus were here used to comparatively investigate the main repair phase events after injury as well as the presence and expression of immune system and extracellular matrix (i.e. collagen) molecules using both microscopy and molecular tools. Our results showed that emergency reaction and re-epithelialisation are similar in both echinoderm models, being faster and more effective than in mammals. Moreover, in comparison to the latter, both echinoderms showed delayed and less abundant collagen deposition at the wound site (absence of fibrosis). The gene expression patterns of molecules related to the immune response, such as Ese-fib-like (starfishes) and Afi-ficolin (brittle stars), were described for the first time during echinoderm regeneration providing promising starting points to investigate the immune system role in these regeneration models. Overall, the similarities in repair events and timing within the echinoderms and the differences with what has been reported in mammals suggest that effective repair processes in echinoderms play an important role for their subsequent ability to regenerate. Targeted molecular and functional analyses will shed light on the evolution of these abilities in the deuterostomian lineage.


Assuntos
Extremidades/fisiologia , Regeneração/fisiologia , Estrelas-do-Mar/fisiologia , Animais , Colágeno/metabolismo , Epiderme/ultraestrutura , Proteínas da Matriz Extracelular/metabolismo , Regulação da Expressão Gênica , Estudos de Associação Genética , Microscopia Eletrônica , Regeneração/genética , Regeneração/imunologia , Especificidade da Espécie , Estrelas-do-Mar/genética , Estrelas-do-Mar/imunologia , Fatores de Transcrição/fisiologia , Cicatrização/fisiologia
13.
Cell Tissue Res ; 370(1): 13-28, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28331971

RESUMO

The potential for repairing and replacing cells, tissues, organs and body parts is considered a primitive attribute of life shared by all the organisms, even though it may be expressed to a different extent and which is essential for the survival of both individual and whole species. The ability to regenerate is particularly evident and widespread within invertebrates. In spite of the wide availability of experimental models, regeneration has been comprehensively explored in only a few animal systems (i.e., hydrozoans, planarians, urodeles) leaving many other animal groups unexplored. The regenerative potential finds its maximum expression in echinoderms. Among echinoderm classes, asteroids offer an impressive range of experimental models in which to study arm regeneration at different levels. Many studies have been recently carried out in order to understand the regenerative mechanisms in asteroids and the overall morphological processes have been well documented in different starfish species, such as Asterias rubens, Leptasterias hexactis and Echinaster sepositus. In contrast, very little is known about the molecular mechanisms that control regeneration development and patterning in these models. The origin and the fate of cells involved in the regenerative process remain a matter of debate and clear insights will require the use of complementary molecular and proteomic approaches to study this problem. Here, we review the current knowledge regarding the cellular, proteomic and molecular aspects of asteroid regeneration.


Assuntos
Regeneração , Estrelas-do-Mar/fisiologia , Animais , Regulação da Expressão Gênica , Proteômica/métodos , Estrelas-do-Mar/anatomia & histologia , Estrelas-do-Mar/genética , Estrelas-do-Mar/ultraestrutura , Cicatrização
14.
Mar Drugs ; 12(9): 4912-33, 2014 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-25255130

RESUMO

Collagen has become a key-molecule in cell culture studies and in the tissue engineering field. Industrially, the principal sources of collagen are calf skin and bones which, however, could be associated to risks of serious disease transmission. In fact, collagen derived from alternative and riskless sources is required, and marine organisms are among the safest and recently exploited ones. Sea urchins possess a circular area of soft tissue surrounding the mouth, the peristomial membrane (PM), mainly composed by mammalian-like collagen. The PM of the edible sea urchin Paracentrotus lividus therefore represents a potential unexploited collagen source, easily obtainable as a food industry waste product. Our results demonstrate that it is possible to extract native collagen fibrils from the PM and produce suitable substrates for in vitro system. The obtained matrices appear as a homogeneous fibrillar network (mean fibril diameter 30-400 nm and mesh < 2 µm) and display remarkable mechanical properties in term of stiffness (146 ± 48 MPa) and viscosity (60.98 ± 52.07 GPa·s). In vitro tests with horse pbMSC show a good biocompatibility in terms of overall cell growth. The obtained results indicate that the sea urchin P. lividus can be a valuable low-cost collagen source for mechanically resistant biomedical devices.


Assuntos
Materiais Biocompatíveis/química , Colágeno/química , Paracentrotus/química , Animais , Fenômenos Biomecânicos , Bovinos , Contagem de Células , Proliferação de Células , Colágeno/ultraestrutura , Humanos , Indicadores e Reagentes , Teste de Materiais , Mercaptoetanol/química , Células-Tronco Mesenquimais/efeitos dos fármacos , Ratos , Suínos , Resistência à Tração , Viscosidade
15.
Cell Tissue Res ; 358(1): 189-201, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25027051

RESUMO

Among echinoderms, crinoids are well known for their remarkable regenerative potential. Regeneration depends mainly on progenitor cells (undifferentiated or differentiated), which migrate and proliferate in the lesion site. The crucial role of the "progenitor" elements involved in the regenerative processes, in terms of cell recruitment, sources, and fate, is a central problem in view of its topical interest and biological implications. The spectacular regenerative potential of crinoids is used to replace lost internal and external organs. In particular, the process of arm regeneration in the feather star Antedon mediterranea is the regeneration model most extensively explored to date. We have addressed the morphological and functional characterization of the cell phenotypes responsible for the arm regenerative processes by using an in vitro approach. This represents the first successful attempt to culture cells involved in crinoid regeneration. A comparison of these results with others from previous in vivo investigations confirms the diverse cell types contributing to regeneration and underscores their involvement in migration, proliferation, and dedifferentiation processes.


Assuntos
Equinodermos/fisiologia , Modelos Biológicos , Regeneração/fisiologia , Células-Tronco/fisiologia , Animais , Desdiferenciação Celular/fisiologia , Diferenciação Celular/fisiologia , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Equinodermos/citologia , Células-Tronco/citologia
16.
J Am Soc Nephrol ; 25(11): 2483-98, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24790181

RESUMO

Renal targets of autoimmunity in human lupus nephritis (LN) are unknown. We sought to identify autoantibodies and glomerular target antigens in renal biopsy samples from patients with LN and determine whether the same autoantibodies can be detected in circulation. Glomeruli were microdissected from biopsy samples of 20 patients with LN and characterized by proteomic techniques. Serum samples from large cohorts of patients with systemic lupus erythematosus (SLE) with and without LN and other glomerulonephritides were tested. Glomerular IgGs recognized 11 podocyte antigens, with reactivity varying by LN pathology. Notably, IgG2 autoantibodies against α-enolase and annexin AI were detected in 11 and 10 of the biopsy samples, respectively, and predominated over other autoantibodies. Immunohistochemistry revealed colocalization of α-enolase or annexin AI with IgG2 in glomeruli. High levels of serum anti-α-enolase (>15 mg/L) IgG2 and/or anti-annexin AI (>2.7 mg/L) IgG2 were detected in most patients with LN but not patients with other glomerulonephritides, and they identified two cohorts: patients with high anti-α-enolase/low anti-annexin AI IgG2 and patients with low anti-α-enolase/high anti-annexin AI IgG2. Serum levels of both autoantibodies decreased significantly after 12 months of therapy for LN. Anti-α-enolase IgG2 recognized specific epitopes of α-enolase and did not cross-react with dsDNA. Furthermore, nephritogenic monoclonal IgG2 (clone H147) derived from lupus-prone MRL-lpr/lpr mice recognized human α-enolase, suggesting homology between animal models and human LN. These data show a multiantibody composition in LN, where IgG2 autoantibodies against α-enolase and annexin AI predominate in the glomerulus and can be detected in serum.


Assuntos
Anexina A1/imunologia , Biomarcadores Tumorais/imunologia , Proteínas de Ligação a DNA/imunologia , Glomérulos Renais/imunologia , Glomérulos Renais/patologia , Nefrite Lúpica/imunologia , Nefrite Lúpica/patologia , Fosfopiruvato Hidratase/imunologia , Proteínas Supressoras de Tumor/imunologia , Adolescente , Adulto , Animais , Anexina A1/isolamento & purificação , Autoanticorpos/sangue , Autoanticorpos/imunologia , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/isolamento & purificação , Biópsia , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/isolamento & purificação , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Masculino , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos MRL lpr , Camundongos SCID , Pessoa de Meia-Idade , Fosfopiruvato Hidratase/genética , Fosfopiruvato Hidratase/isolamento & purificação , Proteômica , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/isolamento & purificação , Adulto Jovem
17.
Mar Environ Res ; 93: 123-32, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24008006

RESUMO

Echinoderms and sponges share a unique feature that helps them face predators and other environmental pressures. They both possess collagenous tissues with adaptable viscoelastic properties. In terms of morphology these structures are typical connective tissues containing collagen fibrils, fibroblast- and fibroclast-like cells, as well as unusual components such as, in echinoderms, neurosecretory-like cells that receive motor innervation. The mechanisms underpinning the adaptability of these tissues are not completely understood. Biomechanical changes can lead to an abrupt increase in stiffness (increasing protection against predation) or to the detachment of body parts (in response to a predator or to adverse environmental conditions) that are regenerated. Apart from these advantages, the responsiveness of echinoderm and sponge collagenous tissues to ionic composition and temperature makes them potentially vulnerable to global environmental changes.


Assuntos
Tecido Conjuntivo/anatomia & histologia , Tecido Conjuntivo/fisiologia , Paracentrotus/anatomia & histologia , Poríferos/anatomia & histologia , Animais , Fenômenos Biomecânicos , Tecido Conjuntivo/ultraestrutura , Meio Ambiente , Microscopia Eletrônica de Transmissão
18.
PLoS One ; 7(11): e49016, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23173042

RESUMO

Mutable collagenous tissues (MCTs) of echinoderms show reversible changes in tensile properties (mutability) that are initiated and modulated by the nervous system via the activities of cells known as juxtaligamental cells. The molecular mechanism underpinning this mechanical adaptability has still to be elucidated. Adaptable connective tissues are also present in mammals, most notably in the uterine cervix, in which changes in stiffness result partly from changes in the balance between matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs). There have been no attempts to assess the potential involvement of MMPs in the echinoderm mutability phenomenon, apart from studies dealing with a process whose relationship to the latter is uncertain. In this investigation we used the compass depressor ligaments (CDLs) of the sea-urchin Paracentrotus lividus. The effect of a synthetic MMP inhibitor - galardin - on the biomechanical properties of CDLs in different mechanical states ("standard", "compliant" and "stiff") was evaluated by dynamic mechanical analysis, and the presence of MMPs in normal and galardin-treated CDLs was determined semi-quantitatively by gelatin zymography. Galardin reversibly increased the stiffness and storage modulus of CDLs in all three states, although its effect was significantly lower in stiff than in standard or compliant CDLs. Gelatin zymography revealed a progressive increase in total gelatinolytic activity between the compliant, standard and stiff states, which was possibly due primarily to higher molecular weight components resulting from the inhibition and degradation of MMPs. Galardin caused no change in the gelatinolytic activity of stiff CDLs, a pronounced and statistically significant reduction in that of standard CDLs, and a pronounced, but not statistically significant, reduction in that of compliant CDLs. Our results provide evidence that MMPs may contribute to the variable tensility of the CDLs, in the light of which we provide an updated hypothesis for the regulatory mechanism controlling MCT mutability.


Assuntos
Adaptação Fisiológica , Ligamentos/enzimologia , Metaloproteinases da Matriz/metabolismo , Fenômenos Mecânicos , Ouriços-do-Mar/enzimologia , Adaptação Fisiológica/efeitos dos fármacos , Animais , Fenômenos Biomecânicos , Dipeptídeos/farmacologia , Elasticidade/efeitos dos fármacos , Ligamentos/efeitos dos fármacos , Ligamentos/fisiologia , Inibidores de Metaloproteinases de Matriz/farmacologia , Ouriços-do-Mar/fisiologia , Resistência à Tração/efeitos dos fármacos , Viscosidade/efeitos dos fármacos
19.
Nephrol Dial Transplant ; 27(10): 3875-84, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23114905

RESUMO

BACKGROUND: Idiopathic retroperitoneal fibrosis (IRF) is a rare fibro-inflammatory disorder characterized by a periaortic tissue which often encases the ureters causing acute renal failure. IRF histology shows fibrosis and a chronic inflammatory infiltrate with frequent tissue eosinophilia. We assessed a panel of molecules promoting eosinophilia and fibrosis in IRF patients and performed an immunogenetic study. METHODS: Serum levels of eotaxin/CCL11, regulated and normal T-cell expressed and secreted (RANTES), granulocyte colony-stimulating factor (G-CSF), interleukin (IL)-5, platelet-derived growth factor (PDGF) and fibroblast growth factor (FGF) were measured using a multiplex assay in 24 newly diagnosed, untreated IRF patients and 14 healthy controls. Retroperitoneal biopsies (available in 8/24 patients) were histologically evaluated to assess eosinophil infiltration, whereas mast cells (MCs) were identified by immunohistochemical analysis for human tryptase. Immunohistochemistry for eotaxin/CCL11 and its receptor CCR3 was also performed. Six single nucleotide polymorphisms (SNPs) within the CCL11 gene (rs6505403, rs1860184, rs4795896, rs17735961, rs16969415 and rs17809012) were investigated in 142 IRF patients and 214 healthy controls. RESULTS: Serum levels of eotaxin/CCL11 were higher in IRF patients than in controls (P = 0.009). Eotaxin/CCL11 drives tissue infiltration of eosinophils and MCs, which can promote fibrosis. Eosinophilic infiltration was prominent (>5 cells/hpf) in five (62.5%) cases, and abundant tryptase-positive MCs were found in all cases; notably, MCs were in a degranulating state. Immunohistochemistry showed that CCL11 was highly produced by infiltrating mononuclear cells and that its receptor CCR3 was expressed by infiltrating eosinophils, MCs, lymphocytes and fibroblasts. None of the tested CCL11 SNPs showed disease association, but the TTCCAT haplotype was significantly associated with IRF (P = 0.0005). CONCLUSIONS: These findings suggest that the eotaxin/CCL11-CCR3 axis is active in IRF and may contribute to its pathogenesis; the TTCCAT haplotype within the CCL11 gene is significantly associated with IRF.


Assuntos
Quimiocina CCL11/metabolismo , Fibrose Retroperitoneal/imunologia , Becaplermina , Estudos de Casos e Controles , Quimiocina CCL11/sangue , Quimiocina CCL11/genética , Quimiocina CCL5/sangue , Eosinófilos/patologia , Feminino , Fator 2 de Crescimento de Fibroblastos/sangue , Estudos de Associação Genética , Fator Estimulador de Colônias de Granulócitos/sangue , Haplótipos , Humanos , Fenômenos Imunogenéticos , Interleucina-5/sangue , Masculino , Mastócitos/patologia , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Proteínas Proto-Oncogênicas c-sis/sangue , Receptores CCR3/metabolismo , Fibrose Retroperitoneal/genética , Fibrose Retroperitoneal/patologia
20.
Clin J Am Soc Nephrol ; 7(9): 1394-400, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22773590

RESUMO

BACKGROUND AND OBJECTIVES: The discovery of different podocyte autoantibodies in membranous nephropathy (MN) raises questions about their pathogenetic and clinical meaning. This study sought to define antibody isotypes and correlations; to compare levels in MN, other glomerulonephritides, and controls; and to determine their association with clinical outcomes. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Serum IgG(1), IgG(3), and IgG(4) against aldose reductase (AR), SOD2, and α-enolase (αENO) were measured at diagnosis in 186 consecutive MN patients, in 96 proteinuric controls (36 with FSGS, and 60 with IgA nephropathy), and in 92 healthy people recruited in four Italian nephrology units. Anti-phospholipase A2 receptor (PLA2r) and anti-neutral endopeptidase (NEP) IgG(4) were titrated in the same specimens. Association with 1-year follow-up clinical parameters was studied in 120 patients. RESULTS: IgG(4) was the most common isotype for all antibodies; IgG(1) and IgG(3) were nearly negligible. IgG(4) levels were positive in a significant proportion of MN patients (AR, 34%; SOD2, 28%; αENO, 43%). Antibody titers were higher in MN than in healthy and pathologic controls (P<0.005). Anti-NEP IgG(4) did not differ from normal controls (P=0.12). Anti-PLA2r IgG(4) was detected in 60% of patients and correlated with anti-AR, anti-SOD2, and anti-αENO IgG(4) (P<0.001). In MN patients negative for the whole antibody panel (20%), 1-year proteinuria was lower compared with patients with at least one antibody positivity (P<0.05). CONCLUSIONS: Our data suggest that IgG(4) is the prevalent isotype for antibodies against cytoplasmic antigens of podocytes (AR, SOD2, αENO). Their levels were higher than in other proteinuric glomerulonephritides and in normal controls and were correlated with anti-PLA2r. Only baseline negativity for all known antibodies predicted lower 1-year proteinuria.


Assuntos
Autoanticorpos/sangue , Glomerulonefrite Membranosa/imunologia , Imunoglobulina G/sangue , Podócitos/imunologia , Adolescente , Adulto , Idoso , Aldeído Redutase/imunologia , Feminino , Glomerulonefrite por IGA/imunologia , Glomerulonefrite Membranosa/sangue , Glomerulonefrite Membranosa/complicações , Glomerulonefrite Membranosa/enzimologia , Glomerulosclerose Segmentar e Focal/imunologia , Humanos , Itália , Modelos Lineares , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Neprilisina/imunologia , Fosfopiruvato Hidratase/imunologia , Podócitos/enzimologia , Proteinúria/imunologia , Receptores da Fosfolipase A2/imunologia , Sistema de Registros , Estudos Retrospectivos , Superóxido Dismutase/imunologia , Fatores de Tempo , Adulto Jovem
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