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1.
Endocrine ; 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38347338

RESUMO

AIMS: Non-Alcoholic-Fatty-Liver-Disease (NAFLD) is the most common cause of chronic liver disease in Western countries; closely linked to obesity and type 2 diabetes (T2DM), it is an additional cardiovascular risk factor. The aim of this study is to investigate the prevalence of NAFLD at T2DM onset. METHODS: 122 newly diagnosed T2DM patients were enroled; NAFLD was diagnosed using ultrasound and fibrosis risk calculated with an FIB4-score. Intermediate and high-risk patients were referred to a hepatologist and underwent transient elastography (TE). RESULTS: At T2DM diagnosis, 25% of patients were overweight, 47% were obese; ultrasound steatosis was present in 79% of patients; the average FIB-4 score was 1.4 (0.7). The NAFLD population was characterised by higher presence of obesity (60%, p 0.06); hypertension (56%, p 0.00); AST (26.3 (23.6) UI/L; p 0.00); ALT (49.3(41.0) UI/L p 0.00); FIB-4 score (1.6 (0.8); p 0.00). Among patients referred to a hepatologist, at TE, 65% had severe steatosis, 22% significant fibrosis and 25% advanced fibrosis. CONCLUSION: This is the first proposal of a NAFLD screening model at T2DM diagnosis. The high prevalence of fibrosis found at the early stage T2DM confirms the compelling need for early management of NAFLD through cost-effective screening and long-term monitoring algorithms.

2.
Phys Rev Lett ; 124(8): 084801, 2020 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-32167359

RESUMO

Cooling of beams of gold ions using electron bunches accelerated with radio-frequency systems was recently experimentally demonstrated in the Relativistic Heavy Ion Collider at Brookhaven National Laboratory. Such an approach is new and opens the possibility of using this technique at higher energies than possible with electrostatic acceleration of electron beams. The challenges of this approach include generation of electron beams suitable for cooling, delivery of electron bunches of the required quality to the cooling sections without degradation of beam angular divergence and energy spread, achieving the required small angles between electron and ion trajectories in the cooling sections, precise velocity matching between the two beams, high-current operation of the electron accelerator, as well as several physics effects related to bunched-beam cooling. Here we report on the first demonstration of cooling hadron beams using this new approach.

4.
Benef Microbes ; 9(3): 389-399, 2018 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-29633636

RESUMO

Current research into original therapies to treat intestinal inflammation is focusing on no-drug therapies. KLD is a mixture of krill oil (KO), probiotic Lactobacillus reuteri (LR), and vitamin D (VitD3). The aim of this study was to assess in vitro and in vivo the potential cooperative effects of KLD in reducing gut inflammation. Colorectal adenocarcinoma cell lines, CACO2 and HT29, and C57BL/6 mice were used for in vitro and in vivo analyses, respectively. Cells were exposed to cytomix (interferon gamma + tumour necrosis factor alpha (TNF-α)) to induce inflammation or co-exposed to cytomix and KO, LR and VitD3 alone or to cytomix and KLD. Animals were treated for 7 days with dextran sodium sulphate (DSS) to induce colitis or with DSS and KLD. In vitro assays: F-actin expression was analysed by immunofluorescence; scratch test and trans-epithelial electric resistance test were performed to measure wound healing; adhesion/invasion assays of adhesive and invasive Escherichia coli (AIEC) bacteria were made; mRNA expression of TNF-α, interleukin (IL)-8 and vitamin D receptor (VDR) was detected by quantitative PCR. In vivo assays: body weight, clinical score, histological score and large intestine weight and length were estimated; mRNA expression of TNF-α, IL-1ß, IL-6, IL-10 by quantitative PCR; VDR expression was detected by quantitative PCR and immunohistochemistry. In vitro: KLD restores epithelial cell-cell adhesion and mucosal healing during inflammation, while decreases the adhesiveness and invasiveness of AIEC bacteria and TNF-α and IL-8 mRNA expression and increases VDR expression. In vivo: KLD significantly improves body weight, clinical score, histological score and large intestine length of mice with DSS-induced colitis and reduces TNF-α, IL-1ß and IL-6 mRNA levels, while increases IL-10 mRNA and VDR levels. KLD has significant effects on the intestinal mucosa, strongly decreasing inflammation, increasing epithelial restitution and reducing pathogenicity of harmful commensal bacteria.


Assuntos
Anti-Inflamatórios/administração & dosagem , Colite/terapia , Sinergismo Farmacológico , Limosilactobacillus reuteri/crescimento & desenvolvimento , Óleos/administração & dosagem , Probióticos/administração & dosagem , Vitamina D/administração & dosagem , Animais , Anti-Inflamatórios/farmacologia , Aderência Bacteriana , Peso Corporal , Linhagem Celular , Colite/induzido quimicamente , Colite/patologia , Citocinas/análise , Sulfato de Dextrana/administração & dosagem , Sulfato de Dextrana/toxicidade , Modelos Animais de Doenças , Euphausiacea , Histocitoquímica , Humanos , Camundongos Endogâmicos C57BL , Modelos Biológicos , Óleos/farmacologia , Probióticos/farmacologia , Resultado do Tratamento , Vitamina D/farmacologia
5.
Eur J Neurol ; 25(6): 799-804, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29512863

RESUMO

BACKGROUND AND PURPOSE: Patients with Parkinson's disease (PD) with resting tremor may be affected by a tremor that appears after a varying latency while a posture is maintained, a phenomenon referred to as re-emergent tremor (RET). The aim of the study was to evaluate the occurrence and clinical features of RET in patients with PD tested off and on treatment, and to compare the effect of dopaminergic treatment on RET with the effect on resting and action tremor. METHODS: We consecutively enrolled 100 patients with PD. Patients were clinically evaluated 24 h after withdrawal of therapy (off-treatment phase) and 60 min after therapy administration (on-treatment phase). We collected the demographic and clinical data of patients with PD. The severity of the disease was assessed by means of the Hoehn and Yahr scale and Movement Disorder Society-sponsored revision of the Unified Parkinson's Disease Rating Scale part III. We evaluated the latency, severity and body side affected both off and on treatment in patients with RET. RESULTS: Re-emergent tremor was present in 24% of the patients with PD off treatment and in 19% of the patients on treatment. Dopaminergic treatment reduced the clinical severity of RET. Dopaminergic treatment increased the number of patients with unilateral RET and reduced the number of those who had bilateral RET. RET and resting tremor responded similarly to dopaminergic treatment, whereas action tremor was less responsive. Patients with RET had milder motor symptoms than patients without RET both off and on treatment. CONCLUSIONS: Dopaminergic treatment modified RET occurrence, severity and body distribution. Dopaminergic depletion plays a role in the pathophysiology of RET.


Assuntos
Antiparkinsonianos/uso terapêutico , Agonistas de Dopamina/uso terapêutico , Levodopa/uso terapêutico , Inibidores da Monoaminoxidase/uso terapêutico , Doença de Parkinson/tratamento farmacológico , Tremor/tratamento farmacológico , Idoso , Quimioterapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/fisiopatologia , Recidiva , Resultado do Tratamento , Tremor/fisiopatologia
6.
Toxicol In Vitro ; 44: 100-110, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28652203

RESUMO

In the last two decades, the use of ozone (O3) as a complementary medical approach has progressively been increasing; however, its application is still limited due to the numerous doubts about its possible toxicity, despite the low concentrations used in therapy. For an appropriate and safe clinical application of a potentially toxic agent such as O3, it is crucial to elucidate the cellular response to its administration. Molecular analyses and transmission electron microscopy were here combined to investigate in vitro the effects of O3 administration on transcriptional activity and nuclear domains organization of cultured SH-SY5Y neuronal cells; low O3 concentrations were used as those currently administered in clinical practice. Mild ozonisation did not affect cell proliferation or death, while molecular analyses showed an O3-induced modulation of some genes involved in the cell response to stress (HMOX1, ERCC4, CDKN1A) and in the transcription machinery (CTDSP1). Ultrastructural cytochemistry after experiments of bromouridine incorporation consistently demonstrated an increased transcriptional rate at both the nucleoplasmic (mRNA) and the nucleolar (rRNA) level. No ultrastructural alteration of nuclear domains was observed. Our molecular, ultrastructural and cytochemical data demonstrate that a mild toxic stimulus such as mild ozonisation stimulate cell protective pathways and nuclear transcription, without altering cell viability. This could possibly account for the positive effects observed in ozone-treated patients.


Assuntos
Núcleo Celular/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Oxidantes/farmacologia , Ozônio/farmacologia , Linhagem Celular Tumoral , Núcleo Celular/ultraestrutura , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p21/genética , Proteínas de Ligação a DNA/genética , Heme Oxigenase-1/genética , Humanos , Microscopia Eletrônica de Transmissão
7.
Int J Immunogenet ; 44(4): 158-163, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28547851

RESUMO

Allelic and genotype frequencies of four cytokine genes were obtained from 738 subjects from North- and South-Italy. Populations were in Hardy-Weinberg equilibrium for all genes but significantly differed in the frequency of all SNPs and three haplotypes. In the MDS graph, they were plotted in separate positions close to Europeans and an Ivorian population, respectively.


Assuntos
Citocinas/genética , Frequência do Gene , Haplótipos , Polimorfismo de Nucleotídeo Único , Feminino , Humanos , Itália , Masculino , Pessoa de Meia-Idade
8.
Eur J Histochem ; 60(2): 2640, 2016 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-27349319

RESUMO

In order to design valid protocols for drug release via nanocarriers, it is essential to know the mechanisms of cell internalization, the interactions with organelles, and the intracellular permanence and degradation of nanoparticles (NPs) as well as the possible cell alteration or damage induced. In the present study, the intracellular fate of liposomes, polymeric NPs and mesoporous silica NPs (MSN) has been investigated in an in vitro cell system by fluorescence and transmission electron microscopy. The tested nanocarriers proved to be characterized by specific interactions with the cell: liposomes enter the cells probably by fusion with the plasma membrane and undergo rapid cytoplasmic degradation; polymeric NPs are internalized by endocytosis, occur in the cytoplasm both enclosed in endosomes and free in the cytosol, and then undergo massive degradation by lysosome action; MSN are internalized by both endocytosis and phagocytosis, and persist in the cytoplasm enclosed in vacuoles. No one of the tested nanocarriers was found to enter the nucleus. The exposure to the different nanocarriers did not increase cell death; only liposomes induced a reduction of cell population after long incubation times, probably due to cell overloading. No subcellular damage was observed to be induced by polymeric NPs and MSN, whereas transmission electron microscopy revealed cytoplasm alterations in liposome-treated cells. This important information on the structural and functional relationships between nanocarriers designed for drug delivery and cultured cells further proves the crucial role of microscopy techniques in nanotechnology.


Assuntos
Citoplasma/metabolismo , Endossomos/metabolismo , Lisossomos/metabolismo , Nanopartículas/metabolismo , Dióxido de Silício/farmacocinética , Células HeLa , Humanos , Lipossomos , Microscopia de Fluorescência , Nanopartículas/química , Dióxido de Silício/química
9.
J Hum Hypertens ; 30(3): 164-70, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26084654

RESUMO

Limited and conflicting data are available about the association between short-term blood pressure (BP) variability and urinary albumin excretion rate (uAER). The objective of our study was to analyze the relationships between microalbuminuria (MAU), defined as an uAER between 20 and 200 µg min(-1), and short-term BP variability (BPV), assessed as average real variability (ARV), weighted s.d. of 24-h BP and as s.d. of daytime and night-time BP. The study population consisted of 315 untreated essential hypertensives with normal estimated glomerular filtration rate (>60 ml min(-1) per 1.73 m(2)), who underwent 24-h ambulatory BP monitoring and 24-h uAER determination. MAU was detected in 82 (26%) patients. ARV of 24-h systolic BP (SBP) was significantly higher in patients with MAU (9.8 (8.5-11.1) mm Hg) when compared with those without it (9.1 (8-10.2) mm Hg; P=0.007). This difference held (P=0.026) after adjustment for age, mean levels of BP and other potential confounders by analysis of covariance. A statistically significant correlation was also found between ARV of 24-h SBP and uAER (r=0.17; P=0.003). This association remained significant (ß=0.15; P=0.01), also taking into account the effect of 24-h average systolic and diastolic BP, age, gender, diabetes, serum uric acid, triglycerides, estimated glomerular filtration rate in multiple regression analyses. All the other indices of short-term BPV tested were not independently associated with MAU. Our results seem to suggest that in essential hypertension, short-term BPV, only when estimated by ARV of 24-h SBP, is independently associated with MAU.


Assuntos
Albuminúria/etiologia , Pressão Sanguínea , Hipertensão/complicações , Adulto , Feminino , Humanos , Hipertensão/fisiopatologia , Hipertensão/urina , Masculino , Pessoa de Meia-Idade
10.
Eur J Histochem ; 59(2): 2515, 2015 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-26150162

RESUMO

Ozone therapy is a modestly invasive procedure based on the regeneration capabilities of low ozone concentrations and used in medicine as an alternative/adjuvant treatment for different diseases. However, the cellular mechanisms accounting for the positive effects of mild ozonization are still largely unexplored. To this aim, in the present study the effects of low ozone concentrations (1 to 20 µg O3/mL O2) on structural and functional cell features have been investigated in vitro by using morphological, morphometrical, cytochemical and immunocytochemical techniques at bright field, fluorescence and transmission electron microscopy. Cells exposed to pure O2 or air served as controls. The results demonstrated that the effects of ozoneadministration are dependent on gas concentration, and the cytoskeletal organization, mitochondrial activity and nuclear transcription may be differently affected. This suggests that, to ensure effective and permanent metabolic cell activation, ozone treatments should take into account the cytological and cytokinetic features of the different tissues.


Assuntos
Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Citoesqueleto/efeitos dos fármacos , Citoesqueleto/ultraestrutura , Imuno-Histoquímica/métodos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/ultraestrutura , Ozônio/farmacologia , Transcrição Gênica/efeitos dos fármacos , Bromodesoxiuridina/metabolismo , Nucléolo Celular/metabolismo , Nucléolo Celular/ultraestrutura , Citoplasma/metabolismo , Citoplasma/ultraestrutura , Relação Dose-Resposta a Droga , Ouro , Proteínas de Choque Térmico HSP70/metabolismo , Células HeLa/efeitos dos fármacos , Células HeLa/ultraestrutura , Humanos , Mitocôndrias/metabolismo , Nanopartículas
11.
Benef Microbes ; 6(2): 225-32, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25851101

RESUMO

Food allergy (FA) is a major health issue for children living in Western countries. At this time the only proven treatment for FA is elimination of offender antigen from the diet. It is becoming clear that the development of gut microbiota exerts a profound influence on immune system maturation and tolerance acquisition. Increasing evidence suggests that perturbations in gut microbiota composition of infants are implicated in the pathogenesis of FA. These findings have unveiled new strategies to prevent and treat FA using probiotics bacteria or bacterial substance to limit T-helper (Th)/Th2 bias, which changes during the disease course. Selected probiotics administered during infancy may have a role in the prevention and treatment of FA. Lactobacillus rhamnosus GG (LGG) is the most studied probiotic in this field. Administration of LGG in early life have a role in FA prevention. Preliminary evidence shows that LGG accelerates oral tolerance acquisition in cow's milk allergic infants. We are understanding the mechanisms elicited by LGG and metabolites in influencing food allergen sensitization. A deeper definition of these mechanisms is opening the way to new immunotherapeutics for children affected by FA that can efficiently limit the disease burden.


Assuntos
Hipersensibilidade Alimentar/tratamento farmacológico , Lacticaseibacillus rhamnosus/fisiologia , Probióticos/administração & dosagem , Animais , Criança , Pré-Escolar , Ensaios Clínicos como Assunto , Hipersensibilidade Alimentar/microbiologia , Hipersensibilidade Alimentar/prevenção & controle , Humanos , Lactente , Resultado do Tratamento
12.
J Endocrinol Invest ; 38(7): 785-90, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25740066

RESUMO

PURPOSE: Varicocele repair in non-obstructive azoospermia (NOA) was occasionally associated to ejaculated spermatozoa independently from clinical and laboratory measures. We performed a prospective study in infertile men affected by NOA and left side varicocele to find whether or not the appearance of ejaculated spermatozoa after varicocele repair is predicted by baseline measures. METHODS: Patients with NOA and grade II, or grade III left side varicocele were submitted to hormone analysis and to scrotal color Doppler ultrasound (CDU). Azoospermia was confirmed in 23 patients aged 25-47 years who were than submitted to varicocele repair through a retrograde internal spermatic vein embolization. Patients were re-evaluated after 6 months. RESULTS: Six months after varicocele repair 12 patients (52.2 %) were still azoospermic (Group 1) while 11 patients (47.8 %) reported ejaculated spermatozoa (Group 2) [sperm count: 1.3 × 10(6)/mL; 0.5 × 10(6)/mL-1.6 × 10(6)/mL (median 25th-75th centiles)]. Serum baseline FSH was lower in Group 2 compared to Group 1 (p = 0.012), while no differences between groups were revealed for all other clinical and laboratory parameters. ROC analysis indicated that baseline FSH level predicted the appearance of ejaculated spermatozoa after treatment [AUC = 0.811; 95 % Confidence Interval (CI) 0.6-0.9; p = 0.0029]. A cut-off level of FSH <10.06 mIU/mL identified 82.0 % of cases with ejaculated spermatozoa with a specificity of 81.8 % and a sensitivity of 83.3 %. CONCLUSION: Selected patients with NOA may show ejaculated spermatozoa after a non-invasive repair of a left side varicocele, therefore avoiding testicular sperm extraction. Baseline serum FSH was a valuable predictor for ejaculated spermatozoa after treatment.


Assuntos
Azoospermia/sangue , Azoospermia/cirurgia , Ejaculação , Embolização Terapêutica , Hormônio Foliculoestimulante/sangue , Espermatozoides , Varicocele/cirurgia , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
13.
Eur J Histochem ; 59(1): 2492, 2015 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-25820565

RESUMO

Chitosan-based nanoparticles (chiNPs) are considered to be potentially good carriers for the sustained intracellular delivery of specific molecules. However, scarce attention has been paid to the long-lasting permanence of these NPs in the intracellular milieu, as well as to their intracellular fate (i.e., distribution, interaction with cell organelles, and degradation) in the long term. In the present study, the presence and subcellular location of FITC-labelled chiNPs were monitored in HeLa cells up to 14 days post-administration using multicolor-fluorescence confocal microscopy and diaminobenzidine photo-oxidation at transmission electron microscopy. The main result of the present study is the demonstration that internalized chiNPs persist inside the cell up to two weeks, occurring in both the cytoplasm and nucleus; accordingly, chiNPs are able to pass from mother to daughter cells through several mitotic cycles. The cells did not show increased mortality or structural damage up to 14 days after chiNP exposure.


Assuntos
Quitosana/metabolismo , Nanopartículas/química , Sobrevivência Celular/efeitos dos fármacos , Quitosana/análise , Quitosana/química , Portadores de Fármacos/análise , Portadores de Fármacos/metabolismo , Células HeLa , Humanos , Microscopia de Fluorescência , Fatores de Tempo
14.
Phys Rev Lett ; 115(26): 264801, 2015 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-26764995

RESUMO

Head-on beam-beam compensation has been implemented in the Relativistic Heavy Ion Collider in order to increase the luminosity delivered to the experiments. We discuss the principle of combining a lattice for resonance driving term compensation and an electron lens for tune spread compensation. We describe the electron lens technology and its operational use. To date, the implemented compensation scheme approximately doubled the peak and average luminosities.

15.
Andrology ; 2(5): 721-8, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24925765

RESUMO

Although high rates of serum testosterone deficiency have been reported in men with spinal cord injury (SCI), its determinants and attributes are not yet established. The aim of this study was to recognize, among putative determinants and attributes of androgen deficiency, those significantly associated to low testosterone after adjustment for confounders recognizable in men with chronic SCI. A biochemical androgen deficiency (total testosterone <300 ng/dL) was exhibited by 18 of 51 patients (35.3%). Significant correlates of testosterone levels were as follows: weekly leisure time physical activity (LTPA) explored by the LTPA Questionnaire for people with SCI, body mass index (BMI), homeostatic model assessment of insulin resistance (HOMA-IR), triglycerides and sexual symptoms, explored by the aging males' symptom (AMS) questionnaire. At the multiple linear regression analysis, among putative determinants of low testosterone, only weekly LTPA and BMI exhibited a significant association with testosterone levels, explaining 54.2 and 9.0% of testosterone variability respectively. At the linear regression models, among various putative attributes of androgen deficiency, only lower sexual desire and, at a lesser extent, higher HOMA-IR, exhibited significant associations with lower testosterone levels, after adjustment for BMI, age, comorbidities and weekly LTPA. In conclusion, poor LTPA, high BMI and low sexual desire are independent predictors of low testosterone in men with chronic SCI. This is relevant to clinical practice, as all these features are routinely assessed in rehabilitation settings for SCI. As poor LTPA and high BMI are modifiable life-style related risk factors, prospective studies could clarify whether life-style modification could increase the level of testosterone and improve the low sexual desire, relevant clinical attribute of low testosterone in men with SCI.


Assuntos
Índice de Massa Corporal , Libido , Atividade Motora , Traumatismos da Medula Espinal/sangue , Testosterona/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento , Humanos , Resistência à Insulina , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Triglicerídeos/sangue , Adulto Jovem
16.
Andrology ; 2(4): 502-9, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24692267

RESUMO

Gram-negative bacteria frequently involved in urogenital tract infections release the endotoxin lipopolysaccharide (LPS); its receptor, toll-like receptor-4 (TLR4), has been recently identified in human spermatozoa, and its direct activation has been suggested in mediating adverse effects of LPS on human spermatozoa. However, the underlying signal transduction remains to be clarified. In other cell types, LPS induces the generation of endocannabinoids, which are involved in mediating endotoxin effects. In human spermatozoa, which exhibit a completely functional endocannabinoid system, the activation of cannabinoid receptor-1 (CB1) inhibited sperm mitochondrial membrane potential (ΔΨm). In this study, we tested the hypothesis of a contribution of CB1 activation by sperm-generated endocannabinoids in the adverse effects exerted by LPS on human spermatozoa. The exposure of motile sperm suspensions to E. coli LPS produced a significant decrease in sperm ΔΨm, assessed at flow cytometry with JC-1, similar to that induced by Metanandamide (Met-AEA), a non-hydrolyzable analogue of the endocannabinoid AEA. The LPS-induced inhibition of ΔΨm was prevented by the selective CB1 cannabinoid receptor antagonist, SR141716. However, the inhibition of ΔΨm induced by either LPS or Met-AEA did not affect sperm motility. Consistent with this finding, the CB1-mediated inhibition of ΔΨm was neither associated to mitochondrial generation of reactive oxygen species as evaluated by flow cytometry with MytoSox Red nor to apoptosis pathway activation as evaluated with cytoflorimetric assay for activated caspase-9 and caspase-3. Any oxidative genomic damage was also ruled out with the cytoflorimetric quantification of the oxidized base adduct 8-hydroxy-2'-deoxyguanosine. In conclusion, E. coli LPS inhibited sperm ΔΨm through the activation of CB1, but this effect was not accompanied to the activation of mitochondrial dysfunction-related apoptotic/oxidative mechanisms, which could affect sperm motility and genomic integrity.


Assuntos
Lipopolissacarídeos/farmacologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Receptor CB1 de Canabinoide/fisiologia , Espermatozoides/efeitos dos fármacos , 8-Hidroxi-2'-Desoxiguanosina , Desoxiguanosina/análogos & derivados , Desoxiguanosina/metabolismo , Humanos , Masculino , Mitocôndrias/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Motilidade dos Espermatozoides/efeitos dos fármacos , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/metabolismo
17.
Micron ; 59: 44-51, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24530364

RESUMO

During the last three decades, diaminobenzidine photo-oxidation has been applied in a variety of studies to correlate light and electron microscopy. Actually, when a fluorophore is excited by light, it can induce the oxidation of diaminobenzidine into an electron-dense osmiophilic product, which precipitates in close proximity to the fluorophore, thereby allowing its ultrastructural detection. This method has very recently been developed for two innovative applications: tracking the fate of fluorescently labeled nanoparticles in single cells, and detecting the subcellular location of photo-active molecules suitable for photodynamic therapy. These studies established that the cytochemical procedures exploiting diaminobenzidine photo-oxidation represent a reliable tool for detecting, inside the cells, with high sensitivity fluorescing molecules. These procedures are trustworthy even if the fluorescing molecules are present in very low amounts, either inside membrane-bounded organelles, or at the surface of the plasma membrane, or free in the cytosol. In particular, diaminobenzidine photo-oxidation allowed elucidating the mechanisms responsible for nanoparticles internalization in neuronal cells and for their escape from lysosomal degradation. As for the photo-active molecules, their subcellular distribution at the ultrastructural level provided direct evidence for the lethal multiorganelle photo-damage occurring after cell photo-sensitization. In addition, DAB photo-oxidized samples are suitable for the ultrastructural detection of organelle-specific molecules by post-embedding gold immunolabeling.


Assuntos
Amina Oxidase (contendo Cobre)/metabolismo , Microscopia Eletrônica de Transmissão/métodos , Nanopartículas/química , Fármacos Fotossensibilizantes/química , Tecnologia Biomédica , Linhagem Celular Tumoral , Citosol/química , Citosol/ultraestrutura , Células HeLa , Humanos , Organelas/química , Organelas/ultraestrutura , Fotoquimioterapia/métodos
18.
Histochem Cell Biol ; 141(5): 551-8, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24357163

RESUMO

Chitosan nanoparticles (NPs) are biocompatible drug carriers able to cross the blood-brain barrier and represent a promising drug delivery system to the central nervous system. We used chitosan NPs to deliver the D-Ala2-D-Leu5-enkephalin (DADLE) to neuronal cells in vitro. DADLE is a hypometabolising synthetic opioid potentially useful for biomedical applications, but its short plasmatic half-life makes its in vivo administration ineffective. Here, we demonstrate by immunoelectron microscopy that (1) chitosan NPs are capable to deliver the opioid to neuronal cells; (2) DADLE is released from the internalised, opioid-loaded NPs up to 48 h; (3) in the nucleus, DADLE binds the transcription/splicing sites; (4) cells treated with DADLE-loaded NPs undergo a decrease in transcription factor amounts and proliferation rate without damage to cell organelles. In this model, chitosan NPs protected the loaded opioid from degradation, thereby prolonging its intracellular effects. These findings suggest that these NPs are efficient for the systemic and tissue administration of opioids in vivo.


Assuntos
Quitosana/química , Portadores de Fármacos/química , Leucina Encefalina-2-Alanina/metabolismo , Nanopartículas/química , Neurônios/metabolismo , Animais , Transporte Biológico , Células Cultivadas , Quitosana/metabolismo , Portadores de Fármacos/metabolismo , Leucina Encefalina-2-Alanina/administração & dosagem , Microscopia de Fluorescência , Neurônios/citologia , Tamanho da Partícula , Ratos , Propriedades de Superfície
19.
Eur J Histochem ; 57(3): e26, 2013 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-24085275

RESUMO

Diaminobenzidine photoconversion is a technique by which a fluorescent dye is transformed into a stably insoluble, brown, electrondense signal, thus enabling examination at both bright field light microscopy and transmission electron microscopy. In this work, a procedure is proposed for combining photoconversion and immunoelectron microscopy: in vitro cell cultures have been first submitted to photoconversion to analyse the intracellular fate of either fluorescent nanoparticles or photosensitizing molecules, then processed for transmission electron microscopy; different fixative solutions and embedding media have been used, and the ultrathin sections were finally submitted to post-embedding immunogold cytochemistry. Under all conditions the photoconversion reaction product and the target antigen were properly detected in the same section; Epon-embedded, osmicated samples required a pre-treatment with sodium metaperiodate to unmask the antigenic sites. This simple and reliable procedure exploits a single sample to simultaneously localise the photoconversion product and a variety of antigens allowing a specific identification of subcellular organelles at the ultrastructural level.


Assuntos
Células/ultraestrutura , Corantes Fluorescentes/química , Ouro/química , Imuno-Histoquímica , 3,3'-Diaminobenzidina/química , Animais , Linhagem Celular , Células Cultivadas , Células HeLa , Humanos , Microscopia Eletrônica de Transmissão , Ratos
20.
Eur J Histochem ; 57(2): e15, 2013 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-23807294

RESUMO

Muscleblind-like 1 (MBNL1) is an alternative splicing factor involved in postnatal development of skeletal muscles and heart in humans and mice, and its deregulation is known to be pivotal in the onset and development of myotonic dystrophy (DM). In fact, in DM patients this protein is ectopically sequestered into intranuclear foci, thus compromising the regulation of the alternative splicing of several genes. However, despite the numerous biochemical and molecular studies, scarce attention has been paid to the intranuclear location of MBNL1 outside the foci, although previous data demonstrated that in DM patients various splicing and cleavage factors undergo an abnormal intranuclear distribution suggestive of impaired RNA processing. Interestingly, these nuclear alterations strongly remind those observed in sarcopenia i.e., the loss of muscle mass and function which physiologically occurs during ageing. On this basis, in the present investigation the ultrastructural localization of MBNL1 was analyzed in the myonuclei of skeletal muscles from healthy and DM patients as well as from adult and old (sarcopenic) mice, in the attempt to elucidate possible changes in its distribution and amount. Our data demonstrate that in both dystrophic and sarcopenic muscles MBNL1 undergoes intranuclear relocation, accumulating in its usual functional sites but also ectopically moving to domains which are usually devoid of this protein in healthy adults. This accumulation/delocalization could contribute to hamper the functionality of the whole splicing machinery, leading to a lower nuclear metabolic activity and, consequently, to a less efficient protein synthesis. Moreover, the similar nuclear alterations found in DM and sarcopenia may account for the similar muscle tissue features (myofibre atrophy, fibre size variability and centrally located nuclei), and, in general, for the aging-reminiscent phenotype observed in DM patients.


Assuntos
Núcleo Celular/metabolismo , Músculo Esquelético/patologia , Distrofia Miotônica/patologia , Proteínas de Ligação a RNA/metabolismo , Sarcopenia/patologia , Adolescente , Adulto , Animais , Western Blotting , Núcleo Celular/patologia , Proteínas de Ligação a DNA/metabolismo , Humanos , Camundongos , Pessoa de Meia-Idade , Músculo Esquelético/metabolismo , Transporte Proteico
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