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1.
J Appl Toxicol ; 33(12): 1506-13, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24022940

RESUMO

The aim of our study was to evaluate the effects of gold (Au) and silver (Ag) nanoparticles (NPs) at different concentrations on cultured human osteoarthritic chondrocytes. Cell viability and inducible nitric oxide synthase expression were evaluated by light microscopy. Using transmission electron microscopy (TEM) and field emission gun-based scanning transmission electron microscopy/energy dispersive spectroscopy (FEG-STEM/EDS) allowed us to localize NPs. Gene expression of matrix metalloproteinases 1, 3 and 13 and A disintegrin and metalloproteinase with thrombospondin motifs -4 and -5 were carried out by real-time polymerase chain reaction. A cell viability test indicated a significant dose-dependent cytotoxic effect of both NPs. At concentrations of 160 and 250 µM NP light microscopy showed chondrocytes with signs of apoptosis and an increased presence of inducible nitric oxide synthase. Au-NPs were characterized by FEG-STEM/EDS and TEM analysis localized NPs in cytoplasm and in endocytotic vesicles. On the contrary, the Ag-NPs were undetectable by FEG-STEM/EDS and TEM. Increased gene expression, particularly in matrix metalloproteinase-3, was observed for both NPs (160 µM), but at a concentration of 250 µM the expression of the evaluated genes became lower. Our in vitro studies, although preliminary, suggest that engineered Au and Ag-NPs appear to be harmful for human osteoarthritic chondrocytes in high concentrations (160-250 µM).


Assuntos
Condrócitos/efeitos dos fármacos , Ouro/toxicidade , Nanopartículas Metálicas/toxicidade , Osteoartrite/patologia , Prata/toxicidade , Idoso , Técnicas de Cultura de Células , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Condrócitos/enzimologia , Condrócitos/ultraestrutura , Relação Dose-Resposta a Droga , Ouro/química , Ouro/farmacocinética , Humanos , Imuno-Histoquímica , Metaloproteinases da Matriz/genética , Nanopartículas Metálicas/química , Microscopia Eletrônica de Transmissão e Varredura , Microscopia Eletrônica de Transmissão , Pessoa de Meia-Idade , Óxido Nítrico Sintase Tipo II/genética , Reação em Cadeia da Polimerase em Tempo Real , Prata/química , Prata/farmacocinética
2.
J Androl ; 32(3): 232-9, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-20930194

RESUMO

The aim of this study was to investigate the presence of the different isoforms of tocopherol (T) in seminal plasma (P) and in the sperm fractions of individuals with abnormal (group 1) and normal (group 2) sperm parameters; the relationships between these isoforms and conventional sperm parameters were also explored. Two vitamin E homologues, α-T and δ-T, were identified in the semen of all participants. Although α-T and δ-T concentrations were similar in the semen of the 2 groups, group 1 showed a lower α-T ratio (S/P) (0.90 vs. 1.20, P < .001) and δ-T ratio (0.86 vs 1.13, P = .007) than group 2. In addition, both T ratios were correlated with the percentage of viable cells, detected by eosin staining. These results suggested that α-T and δ-T are not homogeneously distributed in the semen fractions; in normal semen they are more concentrated in the sperm membrane, whereas in abnormal semen the damaged sperm cells may release both Ts in the plasma. To verify whether sperm membrane breakage could alter α-T and δ-T distribution between the seminal plasma and the spermatozoa, normal sperm samples were sonicated; after sonication a consistent sperm plasma membrane fragmentation, highlighted by transmission electron microscopy, and a concomitant release of α-T and δ-T were observed. In conclusion, the Ts coupled directly with the sperm membrane seem to play the main protective role in the semen, and the release of α-T and δ-T in the P fraction is probably an index of lower antioxidant power and sperm quality.


Assuntos
Sêmen/metabolismo , Tocoferóis/metabolismo , alfa-Tocoferol/metabolismo , Humanos , Masculino , Microscopia Eletrônica de Transmissão
3.
Fertil Steril ; 95(1): 289.e11-6, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20579639

RESUMO

OBJECTIVE: To characterize a novel flagellar defect involving 98% of sperm tails. DESIGN: Case report. SETTING: Interdepartmental Centre for Research and Therapy of Male Infertility, Siena, Italy. PATIENT(S): A 45-year-old infertile man with severe asthenozoospermia. INTERVENTION(S): Family history, physical examination, hormonal analysis, microbial assays, semen analysis, transmission and scanning electron microscopy, tubulin distribution investigated by immunocytochemistry, fluorescence in situ hybridization (FISH) for chromosomes 9, 16, 18, X, and Y. MAIN OUTCOME MEASURE(S): Flagellar abnormalities detected by microscopical methods. RESULT(S): An apparent heterogeneity was observed: extremely elongated tails prone to ruptures; coiled tails at different levels with a strongly rolled axoneme or with a curl in the final flagellar segment; and V-shaped, isolated, bent tails. Transmission electron microscopy revealed the presence of normal heads, disorganized flagellar structures, and dynein deficiency. The FISH analysis was normal. CONCLUSION(S): We report a new sperm defect, characterized by abnormal elongation of the tail, which was prone to ruptures at different levels, concomitant with coiled tails, which were impossible to measure in length. This defect remained constant in different examined ejaculates and applied to the entire sperm population of a sterile man, the son of first-degree cousins, indicating a potential genetic origin.


Assuntos
Astenozoospermia/genética , Astenozoospermia/patologia , Cauda do Espermatozoide/patologia , Cauda do Espermatozoide/ultraestrutura , Cromossomos Humanos Par 16 , Cromossomos Humanos Par 18 , Cromossomos Humanos Par 9 , Cromossomos Humanos X , Cromossomos Humanos Y , Diploide , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Masculino , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Pessoa de Meia-Idade , Índice de Gravidade de Doença
4.
Fertil Steril ; 95(5): 1787.e19-23, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21144504

RESUMO

OBJECTIVE: To characterize the association of two systematic sperm defects. DESIGN: Case report. SETTING: University, Interdepartmental Centre for Research and Therapy of Male Infertility. PATIENT(S): Patient 1, 42 years old, and patient 2, 38 years old, both with severe asthenozoospermia. INTERVENTION(S): Family history, physical examination, hormonal analysis, microbial assays, semen analysis, transmission and scanning electron microscopy, immunocytochemistry for tubulin, and fluorescence in situ hybridization (FISH) for chromosomes 18, X, and Y. MAIN OUTCOME MEASURE(S): Admixture of dysplasia of the fibrous sheath (DFS) and head-tail misalignment up to acephalic sperm detected by microscopic methods. RESULT(S): In both patients, DFS was present in incomplete form and was associated with acephalic sperm and abnormal head-tail attachment. In patient 2, spermatozoa were also affected by necrosis that may cause fragmentation leading to short flagella; submicroscopic examination allowed defining only the origin of these "stumpy" tails. Immunofluorescence confirmed the sperm alterations. FISH revealed an altered frequency of diploidy and disomy in patient 2 and a slight increase in diploidy in patient 1. CONCLUSION(S): The importance of ultrastructural sperm evaluation for correct identification of sperm pathologies is evident, particularly regarding assisted reproduction technology and genetic risk assessment.


Assuntos
Astenozoospermia/patologia , Cabeça do Espermatozoide/patologia , Cauda do Espermatozoide/patologia , Espermatozoides/anormalidades , Adulto , Astenozoospermia/diagnóstico , Humanos , Masculino , Análise do Sêmen , Cabeça do Espermatozoide/ultraestrutura , Motilidade dos Espermatozoides/fisiologia , Cauda do Espermatozoide/ultraestrutura , Espermatozoides/patologia , Espermatozoides/ultraestrutura
5.
Reprod Toxicol ; 27(1): 46-54, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19126427

RESUMO

Metal compounds have been associated with male reproductive toxicity in vivo. The aim of the present study was to investigate the in vitro effects of 20 metal compounds using rabbit ejaculated spermatozoa as a study model for spermiotoxicity. Five of the metals tested (arsenic, cadmium, chromium, mercury and vanadium) reduced sperm motility and curvilinear velocity. Ultrastructural analyses revealed three types of damage to sperm head membranes in relation to the metal used: acrosome breakage with formation of various sized microvesicles (arsenic, cadmium, mercury and platinum); a large round hole (arsenic, cadmium and chromium), and numerous folds in the acrosome membrane (vanadium). The vanadium compound, followed by chromium and mercury compounds, determined a higher number of damaged spermatozoa. In conclusion, all the studied metal compounds, at levels higher than 1microM, may reduce sperm kinetic characteristics and probably fertilizing capacity by triggering specific morphological damages to the head and/or by inhibiting motility.


Assuntos
Metais/toxicidade , Espermatozoides/efeitos dos fármacos , Testes de Toxicidade/métodos , Acrossomo/efeitos dos fármacos , Acrossomo/ultraestrutura , Animais , Vesículas Citoplasmáticas/efeitos dos fármacos , Vesículas Citoplasmáticas/ultraestrutura , Relação Dose-Resposta a Droga , Técnicas In Vitro , Masculino , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Modelos Animais , Coelhos , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides/ultraestrutura
6.
Fertil Steril ; 90(4): 1201.e3-8, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18291377

RESUMO

OBJECTIVE: To characterize a flagellar defect involving 95% of the sperm population from an infertile man. DESIGN: Case report. SETTING: Interdepartmental Centre for Research and Therapy of Male Infertility, Siena, Italy. PATIENT(S): A 42-year-old infertile man with severe asthenozoospermia. INTERVENTION(S): Family history, physical examination, hormonal analysis, microbial assays, semen analysis, transmission electron microscopy (TEM) and scanning electron microscopy (SEM), tubulin distribution investigated by immunocytochemistry, fluorescence in situ hybridization for chromosomes 18, X, and Y. MAIN OUTCOME MEASURE(S): Ultrastructural abnormalities of the flagellum detected by methods listed. RESULT(S): Ultrastructural analysis revealed, in 95% of sperm cells, the total absence of the axoneme and outer dense fibers at the principal piece level, whereas the midpiece appeared abnormally long. Tubulin localization showed a total disorganization of the axoneme with a network of microtubular structures emerging randomly at any level of the flagellum. Fluorescence in situ hybridization analysis was normal. CONCLUSION(S): We report a rare sperm tail defect, characterized by abnormal elongation of the midpiece and absence of the axoneme and the outer dense fibers at the principal piece level in 95% of flagella. This defect occurs in the vast majority of the sperm population from a sterile man, and therefore a genetic origin could be hypothesized.


Assuntos
Astenozoospermia/diagnóstico , Astenozoospermia/genética , Axonema/genética , Microtúbulos/patologia , Espermatozoides/patologia , Adulto , Axonema/patologia , Predisposição Genética para Doença/genética , Humanos , Masculino
7.
Cancer Lett ; 263(2): 291-301, 2008 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-18291576

RESUMO

BACKGROUND: C-IRIV/PTR-4 is a novel anticancer vaccine construct composed of immune-reconstituted influenza virosomes (IRIV) assembled with the PTH-rP derived peptide (PTR)-4, a synthetic CTL epitope with HLA-A(*)02.01 amino acid binding motifs. This peptide is able to generate a human PTH-rP specific CTL response with anti-tumor activity in vitro and in mice. MATERIALS AND METHODS: We have investigated the immunological and preventive anti-tumor activity of C-IRIV/PTR-4 compared with the soluble PTR-4 peptide, in HHD mice inoculated with autologous PTH-rP+ tumor cells. RESULTS: Peptide vaccination with either a soluble and an IRIV formulation showed similar immunological activity and the ability to purge the tumor tissue of tumor cell clones able to produce the target antigen (PTR-rP). The most efficient protection from tumor growth was however observed in animals vaccinated with C-IRIV/PTR-4 in which an additional IRIV related anti-angiogenetic effect was detected in the tumor tissue. CONCLUSIONS: These results confirm the immunological activity of PTR-4 vaccination and suggest a more efficacious therapeutic potential of C-IRIV/PTR-4 against bone metastases and malignancies like breast, prostate and lung which very often over-express PTH-rP.


Assuntos
Vacinas Anticâncer/farmacologia , Vírus da Influenza A/imunologia , Neovascularização Patológica/tratamento farmacológico , Proteína Relacionada ao Hormônio Paratireóideo/administração & dosagem , Vacinas Virossomais/farmacologia , Animais , Vacinas Anticâncer/uso terapêutico , Linhagem Celular Tumoral , Citotoxicidade Imunológica , Humanos , Camundongos , Camundongos Transgênicos , Vacinas de Subunidades Antigênicas/uso terapêutico , Vacinas Virossomais/uso terapêutico
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