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1.
Gynecol Endocrinol ; 33(2): 109-112, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27908215

RESUMO

It is a known fact that abnormal seminal liquid specimens contain abnormal amounts of oxygen free radicals and reactive oxygen species (ROS), and that the use of antioxidant molecules both in vivo and in vitro leads to improvement of semen quality in terms of motility, reduction in DNA damage, with obvious consequences on the fertilization potential. Myo-inositol has been observed to have anti-oxidant properties and be present in much greater concentrations specifically in seminal liquid than in the blood. Moreover, there seems to be a direct relationship between myo-inositol and mitochondrial membrane potential (MMP) and sperm motility. Studies performed in vivo have demonstrated that a dietary supplementation with myo-inositol in men undergoing assisted reproduction techniques may improve sperm quality and motility in oligoasthenospermia (OAT) patients. In the following study we utilized myo-inositol in vitro to verify its effect on semen quality in both normal and OAT patients undergoing in vitro fertilization (IVF) with respect to standard sperm medium. In vitro incubation of seminal liquid carried out using myo-inositol (Andrositol-Lab, Lo.Li. Pharma-Roma, Italy) at a concentration of 15 µl/ml improved progressive motility in both normospermia and OAT subjects. In our opinion, myo-inositol may prove to be a useful strategy to improve sperm preparation for clinical use in IVF.


Assuntos
Astenozoospermia/tratamento farmacológico , Fertilização in vitro/métodos , Inositol/farmacologia , Oligospermia/tratamento farmacológico , Motilidade dos Espermatozoides/efeitos dos fármacos , Complexo Vitamínico B/farmacologia , Adulto , Humanos , Masculino
2.
Cell Death Dis ; 6: e1948, 2015 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-26512958

RESUMO

Molecular mechanisms protecting cardiomyocytes from stress-induced death, including tension stress, are essential for cardiac physiology and defects in these protective mechanisms can result in pathological alterations. Bcl2-associated athanogene 3 (BAG3) is expressed in cardiomyocytes and is a component of the chaperone-assisted autophagy pathway, essential for homeostasis of mechanically altered cells. BAG3 ablation in mice results in a lethal cardiomyopathy soon after birth and mutations of this gene have been associated with different cardiomyopathies including stress-induced Takotsubo cardiomyopathy (TTC). The pathogenic mechanism leading to TTC has not been defined, but it has been suggested that the heart can be damaged by excessive epinephrine (epi) spillover in the absence of a protective mechanism. The aim of this study was to provide more evidence for a role of BAG3 in the pathogenesis of TTC. Therefore, we sequenced BAG3 gene in 70 TTC patients and in 81 healthy donors with the absence of evaluable cardiovascular disease. Mutations and polymorphisms detected in the BAG3 gene included a frequent nucleotide change g2252c in the BAG3 3'-untranslated region (3'-UTR) of Takotsubo patients (P<0.05), resulting in loss of binding of microRNA-371a-5p (miR-371a-5p) as evidenced by dual-luciferase reporter assays and argonaute RNA-induced silencing complex catalytic component 2/pull-down assays. Moreover, we describe a novel signaling pathway in cardiomyocytes that leads to BAG3 upregulation on exposure to epi through an ERK-dependent upregulation of miR-371a-5p. In conclusion, the presence of a g2252c polymorphism in the BAG3 3'-UTR determines loss of miR-371a-5p binding and results in an altered response to epi, potentially representing a new molecular mechanism that contributes to TTC pathogenesis.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Reguladoras de Apoptose/genética , Epinefrina/farmacologia , MicroRNAs/fisiologia , Mutação , Cardiomiopatia de Takotsubo/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Reguladoras de Apoptose/metabolismo , Feminino , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Regulação para Cima/efeitos dos fármacos
3.
Acta Biomater ; 25: 16-23, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26162586

RESUMO

One of the significant challenges in bone tissue engineering is the integration of biomaterials designed to facilitate and stimulate mineralization with a simultaneously rapid rate of angiogenesis and vascularization of the tissue construct, a challenge complicated by our lack of knowledge of the interactions among key cell types and scaffold properties. This study compared functional activity of human bone marrow-derived stromal cells (hMSC) seeded onto a porous salt-leached poly(D,L-lactic acid) (PDLLA) scaffolds, with and without the incorporation of silk fibroin fibers and then further investigated their co-culture with human umbilical vein endothelial cells (HUVECs). Cell viability, proliferation, and alkaline phosphatase activity were measured for a range of time points in culture, with osteogenic and angiogenic marker immunolocalization and gene expression at selected stages. Our findings suggest that, despite similar porosity and pore size distribution exhibited by the PDLLA and PDLLA plus silk fibroin scaffolds, there were marked differences in cell distribution and function. In the absence of fibers, a highly osteogenic response was observed in hMSCs in the scaffolds co-cultured with endothelial cells, greater than that observed with hMSCs alone or in either of the scaffolds with fibers added. However, fiber presence clearly better supported endothelial cell cultures, as determined by greater levels of endothelial marker expression at both the gene and protein level after 3 weeks of culture. The design of composite scaffolds integrating beneficial components of differing structures and materials to facilitate appropriate biological responses appears a promising yet challenging avenue of research. STATEMENT OF SIGNIFICANCE: A significant challenge in bone tissue engineering is to promote a rapid vascularization of the tissue construct in parallel to the extracellular matrix mineralization. The design of composite scaffolds integrating beneficial components of differing structures and materials to facilitate appropriate biological responses appears a promising yet challenging avenue of research. Here we investigated cultures of hMSCs and HUVECs on a silk fibroin enhanced PDLLA scaffold, showing that the final output of this in vitro system is not the linear sum of the effects of the single variables. These results are of interest as they demonstrate how the addition of endothelial cells can affect hMSC phenotype and that the output can be further modulated by the introduction of silk fibroin fibers.


Assuntos
Células Endoteliais da Veia Umbilical Humana/citologia , Células-Tronco Mesenquimais/citologia , Osteogênese , Alicerces Teciduais/química , Fosfatase Alcalina/metabolismo , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Regulação da Expressão Gênica , Células Endoteliais da Veia Umbilical Humana/ultraestrutura , Humanos , Células-Tronco Mesenquimais/ultraestrutura , Molécula-1 de Adesão Celular Endotelial a Plaquetas/genética , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Microtomografia por Raio-X
4.
J Tissue Eng Regen Med ; 7(2): 161-8, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22162265

RESUMO

Bone tissue regeneration involves different healing stages and the resulting final hard tissue is formed from natural templates such as fibrous collagen, soft and hard callus and capillary bed. This work aims to evaluate the efficiency of different scaffold geometries with a novel approach: exploring the relationships among scaffold morphologies, cell activity and collagen 3D organization, which serves as a natural template for subsequent mineralization. Among the possible systems to fabricate scaffolds, solvent casting with particulate leaching and microfabrication were used to produce random vs ordered structures from poly(D,L-lactic acid). In vitro biological testing was carried out by culturing a human osteosarcoma-derived osteoblast cell line (MG63) and measuring material cytotoxicity, cell proliferation and migration. Assemblage of collagen fibres was evaluated. A preliminary study of collagen distribution over the two different matrices was performed by confocal laser microscopy after direct red 80 staining. Both of the scaffolds were seen to be a good substrate for cell attachment, growth and proliferation. However, it seems that random, rather than regular, well-ordered porosity induces a more proper collagen fibre distribution and organization, similar to the natural one formed in the early stages of bone repair.


Assuntos
Colágeno/metabolismo , Matriz Extracelular/metabolismo , Alicerces Teciduais/química , Células Cultivadas , Humanos , Ácido Láctico , Microscopia Confocal , Microscopia Eletrônica de Varredura , Microtecnologia , Osteoblastos/citologia , Poliésteres , Polímeros , Coloração e Rotulagem
5.
Oncogene ; 31(5): 573-82, 2012 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-21725362

RESUMO

Replication-dependent histone gene expression is a fundamental process occurring in S-phase under the control of the cyclin-E/CDK2 complex. This process is regulated by a number of proteins, including Flice-Associated Huge Protein (FLASH) (CASP8AP2), concentrated in specific nuclear organelles known as HLBs. FLASH regulates both histone gene transcription and mRNA maturation, and its downregulation in vitro results in the depletion of the histone pull and cell-cycle arrest in S-phase. Here we show that the transcription factor p73 binds to FLASH and is part of the complex that regulates histone gene transcription. Moreover, we created a novel gene trap to disrupt FLASH in mice, and we show that homozygous deletion of FLASH results in early embryonic lethality, owing to arrest of FLASH(-/-) embryos at the morula stage. These results indicate that FLASH is an essential, non-redundant regulator of histone transcription and cell cycle during embryogenesis.


Assuntos
Proteínas Reguladoras de Apoptose/genética , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação a DNA/genética , Desenvolvimento Embrionário/genética , Histonas/genética , Proteínas Nucleares/genética , Proteínas Supressoras de Tumor/genética , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Western Blotting , Proteínas de Ligação ao Cálcio/metabolismo , Ciclo Celular/genética , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/metabolismo , Embrião de Mamíferos/citologia , Embrião de Mamíferos/embriologia , Embrião de Mamíferos/metabolismo , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Genes Letais/genética , Células HCT116 , Células HEK293 , Histonas/metabolismo , Humanos , Masculino , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Nucleares/metabolismo , Ligação Proteica , Interferência de RNA , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transcrição Gênica , Proteína Tumoral p73 , Proteínas Supressoras de Tumor/metabolismo
6.
J Tissue Eng Regen Med ; 5(7): 569-77, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21695798

RESUMO

This study aimed to comprehend the potentialities of the microfabrication to produce tissue-engineering scaffolds. Structures presenting homogeneously distributed pores of size 100 and 200 µm were fabricated through layer-by-layer deposition of filaments of poly(D,L-lactic acid) (PDLLA) prepared from dichloromethane/dimethylformamide solutions. Rheological tests on the solution and molecular weight distributions of PDLLA, solvent cast films and microfabricated scaffolds were performed to determine which material conditions are optimal for the microfabricated system and to identify any possible material modification induced by the process. In vitro qualitative preliminary cell culture studies were conducted using MG63 osteoblast cell lines after assuring the non-cytotoxicity of the scaffold material by the lactate dehydrogenase in vitro toxicology assay; biological evaluations were initially performed using scaffolds with the smaller (100 µm) pore size. Scanning electron microscopy imaging was used to determine cell morphology distribution. A second cell culture test was performed, using the scaffold with the higher (200 µm) porosity. Confocal laser microscopy (CLM) was utilized to examine cell morphology and growth behaviour. Cellular metabolic activity and viability were also examined using Alamar Blue assay and further verifications were performed using CLM. Cell culture studies indicated homogeneous distribution, high viability and metabolic activity. Pore dimension affects cell distribution: pores < 100 µm acted as barrier structures for the MG63 osteoblast cell line; penetration inside the matrix was hindered and cells grew on the outer part. Increasing pore size resulted in a more homogeneous cell distribution and penetration of cells inside the structure was achieved.


Assuntos
Materiais Biocompatíveis , Ácido Láctico/química , Polímeros/química , Linhagem Celular , Humanos , L-Lactato Desidrogenase/metabolismo , Microscopia Eletrônica de Varredura , Osteoblastos/citologia , Poliésteres
7.
Prof Inferm ; 53(3): 161-6, 2000.
Artigo em Italiano | MEDLINE | ID: mdl-12424816

RESUMO

The organization of Stroke Unit improved prognosis of stroke patient. The randomized studies emphasized the importance of nursing in such a structure. In order to improve nursing process in our Stroke Unit, we designed a nurse record which includes a neurological scale, to define dependence classes and guidelines based on Virgina Henderson's theoretical model. In this paper, we present this nurse record and we describe the various steps of its design.


Assuntos
Unidades Hospitalares , Registros de Enfermagem , Acidente Vascular Cerebral/enfermagem , Humanos , Fatores de Risco , Reabilitação do Acidente Vascular Cerebral
8.
FEBS Lett ; 445(2-3): 347-50, 1999 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-10094487

RESUMO

The role of the evolutionarily conserved residue Pro-53 in Proteus mirabilis glutathione transferase B1-1 has been examined by replacing it with a serine residue using site-directed mutagenesis. The effect of the replacement on the activity, thermal stability and antibiotic binding capacity of the enzyme was examined. The results presented support the view that Pro-53 participates in the maintenance of the proper conformation of the enzyme fold rather than playing a direct role in the catalytic reaction. Furthermore, this residue appears to be an important determinant of the antibiotic binding to the enzyme. Experiments with wild type and mutated enzymes provide evidence that glutathione transferases may play an important role in antibiotic resistance exhibited by bacteria.


Assuntos
Glutationa Transferase/fisiologia , Prolina/fisiologia , Proteus mirabilis/enzimologia , Sequência de Aminoácidos , Sequência Conservada , Evolução Molecular , Glutationa/metabolismo , Glutationa Transferase/genética , Glutationa Transferase/metabolismo , Mutagênese Sítio-Dirigida , Prolina/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Recombinantes de Fusão/fisiologia , Espectrofotometria/métodos
10.
Cardiovasc Intervent Radiol ; 8(3): 131-3, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-4075338

RESUMO

Blood that drains into the right atrium through an isolated left superior vena cava (LSVC) can be a complicating condition during cardiac surgery. In cases of LSVC, a double shadow can be present on standard chest X-ray over the left mediastinum. A notch along the lower contour of left atrium has been previously reported by Owen et al. in 4 cases as an indirect sign of this LSVC anomaly. These two indirect signs were evaluated in 135 (4.5%) cases of LSVC, viewing 89 chest radiographs and 40 angiograms. Their incidence, separately (17-45%) or in combination (9-20%), was observed to be frequent enough to justify a systematic search of these signs in open-heart surgery candidates.


Assuntos
Cardiopatias Congênitas/diagnóstico por imagem , Veia Cava Superior/anormalidades , Angiografia , Procedimentos Cirúrgicos Cardíacos , Humanos , Cuidados Pré-Operatórios , Veia Cava Superior/diagnóstico por imagem
11.
Thorac Cardiovasc Surg ; 32(3): 187-9, 1984 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-6206602

RESUMO

An unusual case of interruption of the aortic arch with flow to the descending aorta through the left vertebral and left subclavian arteries is described. The ductus arteriosus was functionally closed. The aortic arch was reconstructed with a PTFE graft, but the patient died because of lung problems, related to a high left-to-right shunt through a ventricular septal defect. A new surgical approach is postulated in view of the unusual hemodynamic features. Surgical control of pulmonary congestion could be the initial step, followed by aortic arch reconstruction later when insertion of a non-restrictive aortic prosthesis is possible.


Assuntos
Aorta Torácica/anormalidades , Síndrome do Roubo Subclávio/patologia , Aorta Torácica/cirurgia , Prótese Vascular , Comunicação Interventricular/patologia , Humanos , Recém-Nascido , Masculino , Politetrafluoretileno
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