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2.
Interact Cardiovasc Thorac Surg ; 32(1): 39-46, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33221889

RESUMO

OBJECTIVES: Despite promising short- and mid-term results for durability of the Trifecta valve, contradictory reports of early structural valve deterioration (SVD) do exist. We investigated the incidence of SVD after surgical aortic valve replacement (SAVR) with the Trifecta in our single-centre experience. METHODS: Data of 347 consecutive patients (mean age 71.6 ± 9.5 years, 63.4% male) undergoing SAVR with the Trifecta between 2011 and 2017 were analysed. Clinical and echocardiographic reports were obtained with a median follow-up of 41 months (1114 patient years). RESULTS: Isolated SAVR was performed in 122 patients (35.2%), whereas 225 patients (64.8%) underwent concomitant procedures. The median EuroSCORE II was 4.0 (0.9; 7.1) and 30-day mortality was 3.7% (n = 13). Kaplan-Meier estimates for the freedom of overall mortality at 1, 5 and 7 years were 88.7 ± 1.7%, 73.7 ± 2.6% and 64.7 ± 4.2%, respectively. SVD was observed in 25 patients (7.2%) with a median time to first diagnosis of 73 months. Freedom of SVD was 92.5 ± 0.9% at 5 years and 65.5 ± 7.1% at 7 years. Thirteen patients underwent reintervention for SVD (6 re-SAVR, 7 valve-in-valve), resulting in a freedom of reintervention for the SVD of 98.5 ± 1.1% at 5 years and 76.9 ± 6.9% at 7 years. CONCLUSIONS: We herein report one of the highest rates of SVD after SAVR with the Trifecta. These data indicate that the durability of the prosthesis decreases at intermediate to long-term follow-up, leading to considerable rates of reintervention due to SVD.

3.
Animals (Basel) ; 10(11)2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-33143113

RESUMO

The aim of this work was to evaluate the efficiency of different FSH doses and FSH coasting times before ovum pick-up (OPU) on follicular growth and oocyte competence in buffalo. Experiment 1 involved two different FSH treatments: 40 mg FSH given three (FSH3) or six (FSH6) times, 2 days after dominant follicle removal were tested, with OPU carried out after 40-44 h of coasting. In experiment 2, OPU was carried out after FSH6 protocol followed by 28-32 h (C1), 40-44 h (C2), or 64-68 h (C3) of coasting time. Cumulus oocyte complexes (COCs) were classified, in vitro matured, fertilized, and cultured. The results demonstrated that FSH6 increased the total number of follicles, the number and percentages of medium and large follicles, the number and the proportion of good quality oocytes, and the number of grade 1,2 and fast-developing blastocysts compared to the control. C3 decreased the percentage of good quality oocyte and blastocyst rates compared to C1 and C2. A higher percentage of fast blastocysts and average number of grade 1,2 blastocysts was observed in C1 compared to C3, with intermediate values found in C2. The improved efficiency in terms of blastocyst yields suggests the use of FSH6 + C1 protocol for ovarian superstimulation in buffalo.

4.
Nucleic Acids Res ; 48(21): 11942-11957, 2020 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-33137181

RESUMO

Genomic DNA and cellular RNAs can form a variety of non-B secondary structures, including G-quadruplex (G4) and R-loops. G4s are constituted by stacked guanine tetrads held together by Hoogsteen hydrogen bonds and can form at key regulatory sites of eukaryote genomes and transcripts, including gene promoters, untranslated exon regions and telomeres. R-loops are 3-stranded structures wherein the two strands of a DNA duplex are melted and one of them is annealed to an RNA. Specific G4 binders are intensively investigated to discover new effective anticancer drugs based on a common rationale, i.e.: the selective inhibition of oncogene expression or specific impairment of telomere maintenance. However, despite the high number of known G4 binders, such a selective molecular activity has not been fully established and several published data point to a different mode of action. We will review published data that address the close structural interplay between G4s and R-loops in vitro and in vivo, and how these interactions can have functional consequences in relation to G4 binder activity. We propose that R-loops can play a previously-underestimated role in G4 binder action, in relation to DNA damage induction, telomere maintenance, genome and epigenome instability and alterations of gene expression programs.


Assuntos
DNA/química , Quadruplex G , Genoma Humano , Estruturas R-Loop , RNA/química , Aminoquinolinas/química , Aminoquinolinas/farmacologia , Pareamento de Bases , DNA/genética , DNA/metabolismo , Quadruplex G/efeitos dos fármacos , Instabilidade Genômica , Guanina/química , Guanina/metabolismo , Humanos , Ligação de Hidrogênio , Ligantes , Modelos Moleculares , Ácidos Picolínicos/química , Ácidos Picolínicos/farmacologia , Regiões Promotoras Genéticas , Estruturas R-Loop/efeitos dos fármacos , RNA/genética , RNA/metabolismo , Telômero/efeitos dos fármacos , Telômero/metabolismo , Telômero/ultraestrutura , Homeostase do Telômero
5.
J Neurosci ; 40(49): 9414-9425, 2020 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-33115926

RESUMO

Odors activate distributed ensembles of neurons within the piriform cortex, forming cortical representations of odor thought to be essential to olfactory learning and behaviors. This odor response is driven by direct input from the olfactory bulb, but is also shaped by a dense network of associative or intracortical inputs to piriform, which may enhance or constrain the cortical odor representation. With optogenetic techniques, it is possible to functionally isolate defined inputs to piriform cortex and assess their potential to activate or inhibit piriform pyramidal neurons. The anterior olfactory nucleus (AON) receives direct input from the olfactory bulb and sends an associative projection to piriform cortex that has potential roles in the state-dependent processing of olfactory behaviors. Here, we provide a detailed functional assessment of the AON afferents to piriform in male and female C57Bl/6J mice. We confirm that the AON forms glutamatergic excitatory synapses onto piriform pyramidal neurons; and while these inputs are not as strong as piriform recurrent collaterals, they are less constrained by disynaptic inhibition. Moreover, AON-to-piriform synapses contain a substantial NMDAR-mediated current that prolongs the synaptic response at depolarized potentials. These properties of limited inhibition and slow NMDAR-mediated currents result in strong temporal summation of AON inputs within piriform pyramidal neurons, and suggest that the AON could powerfully enhance activation of piriform neurons in response to odor.SIGNIFICANCE STATEMENT Odor information is transmitted from olfactory receptors to olfactory bulb, and then to piriform cortex, where ensembles of activated neurons form neural representations of the odor. While these ensembles are driven by primary bulbar afferents, and shaped by intracortical recurrent connections, the potential for another early olfactory area, the anterior olfactory nucleus (AON), to contribute to piriform activity is not known. Here, we use optogenetic circuit-mapping methods to demonstrate that AON inputs can significantly activate piriform neurons, as they are coupled to NMDAR currents and to relatively modest disynaptic inhibition. The AON may enhance the piriform odor response, encouraging further study to determine the states or behaviors through which AON potentiates the cortical response to odor.

6.
J Card Surg ; 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33001443

RESUMO

Left ventricular aneurysms (LVA) are a complication of myocardial infarction, that rarely involve the posterior wall; surgical repair of posterior LVA poses a technical challenge when associated with concomitant mitral regurgitation. We describe a minimally invasive treatment of ischemic MR and concomitant patch exclusion of posterior LVA through a right minithoracotomy. Using a transatrial approach, the aneurysm is closed with a "U" shaped dacron patch, whose base is anchored to the mitral annulus. Two patients were operated by this method with excellent results.

7.
Theriogenology ; 158: 227-232, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32980685

RESUMO

The study aimed to evaluate if the sperm telomere length can be considered as a new biomarker for sperm quality in bulls. Sperm Telomere Length was evaluated by Monochrome Multiplex Quantitative PCR in group A (n = 8) and group B (n = 8) bulls, classified according to standard semen analysis. Also, this parameter was measured before and after Percoll gradient separation within bulls that produced semen of satisfactory quality. Sperm telomere length, measured as T/S ratio (average ratio of telomere repeats copy number to a single copy gene), was higher in group A than in group B bulls (0.77 ± 0.03 vs 0.43 ± 0.06; P < 0.01). Sperm telomere length was positively correlated with motility, viability and membrane integrity, and it was negatively correlated with sperm anomalies. Furthermore, Percoll gradient selected sperms with higher T/S ratio than unselected sperms (1.19 ± 0.02 vs 0.67 ± 0.03). These results suggest that sperm telomere length can be used as a new marker of bovine semen quality.

9.
Sci Rep ; 10(1): 13557, 2020 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-32782284

RESUMO

Season clearly influences oocyte competence in buffalo (Bubalus bubalis); however, changes in the oocyte molecular status in relation to season are poorly understood. This study characterizes the microRNA (miRNA) and transcriptomic profiles of oocytes (OOs) and corresponding follicular cells (FCs) from buffalo ovaries collected in the breeding (BS) and non-breeding (NBS) seasons. In the BS, cleavage and blastocyst rates are significantly higher compared to NBS. Thirteen miRNAs and two mRNAs showed differential expression (DE) in FCs between BS and NBS. DE-miRNAs target gene analysis uncovered pathways associated with transforming growth factor ß (TGFß) and circadian clock photoperiod. Oocytes cluster in function of season for their miRNA content, showing 13 DE-miRNAs between BS and NBS. Between the two seasons, 22 differentially expressed genes were also observed. Gene Ontology (GO) analysis of miRNA target genes and differentially expressed genes (DEGs) in OOs highlights pathways related to triglyceride and sterol biosynthesis and storage. Co-expression analysis of miRNAs and mRNAs revealed a positive correlation between miR-296-3p and genes related to metabolism and hormone regulation. In conclusion, season significantly affects female fertility in buffalo and impacts on oocyte transcriptomic of genes related to folliculogenesis and acquisition of oocyte competence.


Assuntos
MicroRNAs/genética , Oócitos/metabolismo , Oogênese , Folículo Ovariano/metabolismo , Estações do Ano , Transcriptoma , Animais , Búfalos , Feminino , Técnicas de Maturação in Vitro de Oócitos/métodos , Oócitos/citologia , Folículo Ovariano/citologia
10.
Animals (Basel) ; 10(8)2020 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-32824834

RESUMO

Alimentary lymphoma (AL) is the most common malignancy of the feline gastrointestinal tract and may cause variable mild to severe alteration of the gastric wall on ultrasonography (US) that can be very similar to those caused by inflammation (INF). The aim of this prospective study is to establish the value of B-mode and contrast-enhanced US (CEUS) in describing specific features of normal, inflammatory, and neoplastic gastric diseases in feline species. B-mode US and CEUS of the stomach were performed in anesthetized cats with or without gastric disorders. Gastric wall qualitative and quantitative parameters were evaluated on B-mode US and CEUS examination. A total of 29 cats were included: six healthy (HEA) cats as the control group; nine INF; three low-grade lymphoma (LGAL); 10 high-grade lymphoma (HGAL). On B-mode US, there were significant differences in thickness, the wall's layer definition and echogenicity between HGAL and all the other groups (<0.001). For CEUS, statistical differences between groups were found in the following: HGAL vs. HEA, HGAL vs. INF; HGAL vs. LGAL; INF vs. HEA. Diagnostic accuracy (AUC) and cut-off value were calculated and found to be significant for thickness (3.8 mm) for INF vs. LGAL (AUC > 0.70) and "benign" vs. "malignant" (AUC > 0.90) as well as peak enhancement (34.87 dB) for "benign" vs. "malignant" (AUC > 0.70). INF and LGAL showed an overlap of qualitative and quantitative parameters both on B-mode and CEUS, while HGAL usually appears as a severe wall thickening with absent layer definition, high-contrast uptake, a specific enhancement pattern, regional lymphadenopathy and local steatitis. Thickness and peak enhancement can be useful parameters in the characterization of gastric infiltrates in cats.

11.
Diabetes Metab Res Rev ; : e3392, 2020 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-32783395

RESUMO

BACKGROUND: We evaluate whether the Pro12Ala polymorphism of peroxisome proliferator-activated receptor γ2 (PPARγ2) has a role in the progression of diabetes by modulating the occurrence of treatment failure to glucose-lowering drugs. METHODS: We studied 215 patients with type 2 diabetes participating in the Thiazolidinediones Or Sulphonylureas and Cardiovascular Accidents Intervention Trial study. All participants were insufficiently controlled (glycated haemoglobin [HbA1c ] 7.0%-9.0%) with metformin 2 g/day and were randomly allocated to add-on pioglitazone or a sulfonylurea. Treatment failure was defined as HbA1c ≥8% on two consecutive visits, 3 months apart. RESULTS: Carriers or non-carriers of the polymorphism had similar age, body mass index, and diabetes duration. Ala carriers had lower fasting plasma insulin, better insulin sensitivity (Homeostasis Model Assessment [HOMA]2-%S), and worse beta cell secretion (HOMA2-%B) than non-carriers. During 24 months of follow-up, 32.5% among the Ala carriers and 8.6% among non-carriers (P < 0.001) developed treatment failure with a cumulative incidence of 18.6 vs 4.6/100 person-years. Those patients who developed treatment failure were older, had a younger age at diabetes diagnosis (48 ± 10 vs 52 ± 7 years; P = 0.032), higher HbA1c (8.1 ± 0.5 vs 7.7 ± 0.5%; P < 0.001), and lower HOMA2-%B (30 ± 12 vs 46 ± 29; P = 0.015) at study entry, as compared to those who did not develop treatment failure. At multivariate analysis, the Pro12Ala polymorphism was significantly associated with treatment failure (hazard ratio [HR] 4.45; 95% confidence interval [CI] 1.79-11.1; P < 0.001); HbA1c at study entry was the other independent predictor of failure in this study population. CONCLUSION: The Pro12Ala polymorphism is associated with a greater insulin sensitivity, reduced beta cell function and a substantially increased risk of treatment failure.

12.
Animals (Basel) ; 10(7)2020 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-32668625

RESUMO

This study evaluated corpus luteum (CL) development in buffaloes out of breeding season and assessed an early pregnancy diagnosis. Mediterranean buffaloes (n = 29) were synchronized and artificially inseminated. CL B-mode/color Doppler ultrasonography examinations were performed daily from Days 5 to 10 post-synchronization, recording CL dimensions and blood flow parameters. Blood samples were collected on the same days for the progesterone (P4) assay. Data were grouped into pregnant or nonpregnant and retrospectively analyzed. The total pregnancy rate was 50.0% (13/26) on Day 45. A significant difference between CL average area in pregnant and nonpregnant buffaloes was recorded only on Day 10. Pregnant buffaloes showed a significantly higher mean P4 concentration and higher mean time average medium velocity (TAMV) values from Day 5 to Day 10 compared to nonpregnant buffaloes. Linear regression analysis showed a significant relationship between P4 levels and TAMV. Multiple logistic regression highlighted a significant influence of TAMV on pregnancy outcome, particularly on Day 8. This is probably due to the strong relationship between TAMV and P4 production. Both TAMV and P4 could be used to predict pregnancy starting on Day 6, although a more reliable result was obtained at Day 10. Thus, the period between Days 5 and 10 is critical for CL development during the transitional period in buffalo.

13.
Front Vet Sci ; 7: 299, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32626727

RESUMO

The present study aimed to assess the applicability of luteal blood flow data acquired through the use of color Doppler ultrasonography and a post-processing analysis tool (ImageJ) for predicting pregnancy in buffaloes (Bubalus bubalis). The experiment was carried out on 59 multiparous Italian Mediterranean buffaloes that underwent synchronization of estrus and fixed-time artificial insemination (TAI). Corpus luteum features (size: CLS and blood flow: BFA) were taken from Day 5 to 10 after TAI and retrospectively measured with ImageJ. In the same period, blood samples were taken to assess progesterone (P4) concentrations. Pregnancy diagnosis was carried out on Day 45 by ultrasound and confirmed on Day 70 post-TAI. Differences in CLS, BFA, and P4 concentrations from Day 5 to 10 after TAI measured between groups were analyzed by ANOVA repeated measures as were differences within each day of measuring. Buffaloes that established a pregnancy (n = 29; 55%) had larger CLS (2.2 ± 0.1 vs. 1.9 ± 0.1 cm2; P < 0.01), higher BFA (0.6 ± 0.0 vs. 0.4 ± 0.0 cm2; P < 0.01), and higher P4 blood level (1.8 ± 0.1 vs. 1.4 ± 0.1; P < 0.01) during Day 5-10 as compared to not-pregnant buffaloes (n = 22). Throughout the entire period, the first feature that changed between groups was P4 blood concentration at Day 7 (1.7 ± 0.1 vs. 1.2 ± 0.1; P < 0.05) followed by BFA at Day 8 (0.6 ± 0.0 vs. 0.5 ± 0.0; P < 0.05), respectively, in pregnant and not-pregnant animals. The ROC analyses indicated that P4 was able to predict pregnancy since Day 5 (P < 0.05) although a more reliable result could be obtained from Day 8 (P < 0.01). At Day 10, it was possible to set a cutoff value for every parameter taken into account. The logistic regression analysis showed that pregnancy was positively influenced by P4 concentration (odds ratio 534.127; P < 0.01) and BFA (odds ratio 744.893; P < 0.01). In conclusion, the use of color Doppler ultrasonography, together with ImageJ, identified different patterns of BFA between pregnant and not-pregnant buffaloes starting from Day 8 post-TAI.

14.
Endocr J ; 67(11): 1093-1098, 2020 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-32669509

RESUMO

Previous reports indicate that selenium supplementation may be useful to reduce cell oxidative stress. In particular, selenium may decrease the level of thyroid autoantibodies in patients with Hashimoto's thyroiditis (HT). Recent studies also indicate that myo-inositol may have beneficial effects on thyroid function in patients with HT. Hence, the aim of the present study is to evaluate whether myo-inositol may enhance the protective effect of selenium on HT progression to hypothyroidism. The study was designed as observational and retrospective. Thyroid hormones were evaluated in patients with HT who were either euthyroid or subclinically hypothyroid. These patients were subdivided into three groups: untreated, treated with selenomethionine alone (Se-meth: 83 µg/day) and treated with Se-meth plus myo-inositol (Se-meth + Myo-I: 83 µg/day + 600 mg/day). Outcome evaluation was performed at baseline and after 6 and 12 months of treatment. High-resolution ultrasound of the thyroid gland was performed to evaluate changes in thyroid echoic pattern during the study. Compared to baseline, levels of thyroid-stimulating hormone (TSH) increased significantly in untreated patients but decreased by 31% and 38%, respectively, in those treated with Se-meth and Se-meth + Myo-I. Moreover, in the latter group the TSH reduction was observed earlier than in the Se-meth-treated group. Densitometric analysis of thyroid ultrasonography showed an echoic pattern improvement in both treated groups compared to untreated patients, although this difference was not statistically significant. Thus, Se-meth treatment is effective in patients with HT and its effect may be improved in combination with Myo-I through earlier achievement of TSH levels closer to physiological concentrations.

15.
Hormones (Athens) ; 2020 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-32500462

RESUMO

BACKGROUND: Immune checkpoint blockade therapy may lead to thyroid dysfunction in 3-7% of treated patients. Alemtuzumab is a CD52 inhibitor leading to thyroid dysfunction in approximately 40% of patients. A female patient was affected by multiple sclerosis (MS) and subclinical hyperthyroidism due to an autonomously functioning thyroid nodule (AFTN). After alemtuzumab treatment, she developed aggressive clinical hyperthyroidism consistent with Marine-Lenhart syndrome. CASE PRESENTATION: A 36-year-old woman presented in July 2019 with symptoms of hyperthyroidism and eye complaints. Three years earlier, she was diagnosed with MS. Subclinical hyperthyroidism was diagnosed in April 2017. Thyroid scintigraphy showed an intranodular distribution of 99mTc-pertechnatate consisting of an AFTN in the right lobe of the thyroid. In June 2018, because of the MS, she was treated with alemtuzumab. In November 2018, she was started on methimazole treatment because of the symptoms of hyperthyroidism. In December 2018, thyroid function was normal under methimazole treatment. In June 2019, the patient received a second round of alemtuzumab administration. One month later, she developed symptoms of hyperthyroidism. These symptoms were accompanied by diplopia. Blood tests showed severe hyperthyroidism. Thyroid scintigraphy showed a diffuse distribution of 99mTc-pertechnatate and the presence of a "cool" area in the right lobe of the thyroid, confirmed by ultrasonography. The nodule was diagnosed as a low-risk indeterminate lesion. CONCLUSION: We present a case of Graves' disease with active, moderate-to-severe Graves' ophthalmopathy in a patient with pre-existing AFTN presenting with a coexisting, rare case of Marine-Lenhart syndrome associated with immune reconstitution after alemtuzumab treatment.

16.
Artigo em Inglês | MEDLINE | ID: mdl-32595602

RESUMO

Background: A course of anti-thyroid drugs (ATD) is the most common first line treatment for Graves' hyperthyroidism. However, hyperthyroidism relapse is frequent (30-70%). Due to the autoimmune nature of Graves' disease, the immunosuppressive treatment used for active Graves' orbitopathy (GO) may reduce the relapses after ATD discontinuation. Objective: To evaluate the recurrence rate in Graves' patients who, in addition to standard ATD, were treated or not treated with parenteral methylprednisolone (MPDS) for GO. Methods: Single-center retrospective study in a continuous series of 162 newly diagnosed Graves' patients, with or without GO, all gone into remission and followed-up until hyperthyroidism recurrence or at least 4 years after ATD discontinuation. Patients with moderate-severe active GO underwent middle dose MPDS treatment according to the EuGoGo guidelines. Cox proportional-hazard model was used to comparatively evaluate the risk of recurrence and the predictive factors in patients treated or not treated with MPDS pulse therapy. Results: MPDS treatment was the most significant factor that independently correlated with a reduced risk of hyperthyroidism relapse (HR = 0.53, 95% C.I. = 0.31-0.89). FT3 and female sex were also independent protective factors, while age almost reached the significance level, p = 0.062. The efficacy of MPDS was very high in patients aged <40 years (42.1% decrease in relapses, p < 0.01) but it was not significant in older patients. Discussion: Our study found that after ATD discontinuation the frequency of Graves' hyperthyroidism relapse was reduced in patients treated with MPDS pulse therapy for GO. This effect was more marked in young patients.

18.
Int J Mol Sci ; 21(10)2020 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-32408629

RESUMO

Thyroid cancer incidence is significantly increased in volcanic areas, where relevant non-anthropogenic pollution with heavy metals is present in the environment. This review will discuss whether chronic lifelong exposure to slightly increased levels of metals can contribute to the increase in thyroid cancer in the residents of a volcanic area. The influence of metals on living cells depends on the physicochemical properties of the metals and their interaction with the target cell metallostasis network, which includes transporters, intracellular binding proteins, and metal-responsive elements. Very little is known about the carcinogenic potential of slightly increased metal levels on the thyroid, which might be more sensitive to mutagenic damage because of its unique biology related to iodine, which is a very reactive and strongly oxidizing agent. Different mechanisms could explain the specific carcinogenic effect of borderline/high environmental levels of metals on the thyroid, including (a) hormesis, the nonlinear response to chemicals causing important biological effects at low concentrations; (b) metal accumulation in the thyroid relative to other tissues; and (c) the specific effects of a mixture of different metals. Recent evidence related to all of these mechanisms is now available, and the data are compatible with a cause-effect relationship between increased metal levels in the environment and an increase in thyroid cancer incidence.

19.
Materials (Basel) ; 13(7)2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-32235560

RESUMO

Glycerol is the main by-product of biodiesel production. For this reason, its valorization into value-added products, by using green procedures, represents an important goal. Different sulfonic acid silica- or titania-based catalysts were prepared, characterized and tested in the glycerol etherification process, assisted by microwaves, in order to obtain biodiesel additives. The surface and structural properties of the catalysts were investigated by means of N2 adsorption isotherms, thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS) and acid capacity measurements by X-Ray Fluorescence Spectroscopy (XRF). The best performance in terms of activity was achieved in the presence of the sulfonic function directly linked to the amorphous silica. By the correlation of the structure properties of the materials and their activity, the performance of the catalysts was shown to be influenced mainly by the surface area, pore volume and acidity. Recycling experiments performed over the most active systems showed that the sulfonic silica-based materials maintained their performance during several cycles.

20.
Crit Rev Oncol Hematol ; 150: 102950, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32339980

RESUMO

Incidence and mortality of thyroid cancer are increasing, thus making mandatory to improve the knowledge of disease etiology. The hypothesis of a role for anthropogenic chemicals is raising wide consideration. A series of occupational studies revealed that job exposures with high risk of chemical contamination were usually more prone to thyroid cancer development. These include shoe manufacture, preserving industry, building activities, pulp/papermaker industry and the wood processing, agricultural activities, and other work categories characterized by contact with chemicals, such as chemists and pharmacists. However, such epidemiological analyses cannot define a causal relationship. Thyroid-disrupting activity has emerged for a broad set of anthropogenic chemicals, with the best evidence being gained for polychlorinated biphenyls, polybrominated diphenyl ethers, dioxins, bisphenols, phthalates, pesticides, and heavy metals. A series of case-control studies, assessing exposure to thyroid-disrupting agents, as measured on biological matrices, have been recently performed providing the following insights: a) positive relationship with thyroid cancer was found for phthalates, bisphenols, the heavy metals cadmium, copper, and lead; b) polybrominated diphenyl ethers exposure showed no relationship with thyroid cancer c) controversial results were reported for polychlorinated biphenyls and pesticides. However, such studies cannot demonstrate the causal link with disease occurrence, as exposure is assessed after tumour development. Studies with different methodological approach are therefore required for defining the role of anthropogenic environmental chemicals in thyroid carcinogenesis.


Assuntos
Dioxinas/efeitos adversos , Poluentes Ambientais/efeitos adversos , Praguicidas/efeitos adversos , Bifenil Polibromatos/efeitos adversos , Bifenilos Policlorados/efeitos adversos , Glândula Tireoide/efeitos dos fármacos , Neoplasias da Glândula Tireoide/induzido quimicamente , Monitoramento Ambiental , Poluentes Ambientais/metabolismo , Éteres Difenil Halogenados , Humanos , Praguicidas/metabolismo , Fenóis/toxicidade , Éteres Fenílicos/efeitos adversos , Glândula Tireoide/fisiologia
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