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1.
Ann Oncol ; 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38908482

RESUMO

BACKGROUND: Hormone receptor expression is a known positive prognostic and predictive factor in breast cancer; however, limited evidence exists on its prognostic impact on prognosis of young patients harboring a pathogenic variant (PV) in the BRCA1 and/or BRCA2 genes. PATIENTS AND METHODS: This international, multicenter, retrospective cohort study included young patients (aged ≤40 years) diagnosed with invasive breast cancer and harboring germline PVs in BRCA genes. We investigated the impact of hormone receptor status on clinical behavior and outcomes of breast cancer. Outcomes of interest [disease-free survival (DFS), breast cancer-specific survival (BCSS), and overall survival (OS)] were first investigated according to hormone receptor expression (positive versus negative), and then according to breast cancer subtype [luminal A-like versus luminal B-like versus triple-negative versus human epidermal growth factor receptor 2 (HER2)-positive breast cancer]. RESULTS: From 78 centers worldwide, 4709 BRCA carriers were included, of whom 2143 (45.5%) had hormone receptor-positive and 2566 (54.5%) hormone receptor-negative breast cancer. Median follow-up was 7.9 years. The rate of distant recurrences was higher in patients with hormone receptor-positive disease (13.1% versus 9.6%, P < 0.001), while the rate of second primary breast cancer was lower (9.1% versus 14.7%, P < 0.001) compared to patients with hormone receptor-negative disease. The 8-year DFS was 65.8% and 63.4% in patients with hormone receptor-positive and negative disease, respectively. The hazard ratio of hormone receptor-positive versus negative disease changed over time for DFS, BCSS, and OS (P < 0.05 for interaction of hormone receptor status and survival time). Patients with luminal A-like breast cancer had the worst long-term prognosis in terms of DFS compared to all the other subgroups (8-year DFS: 60.8% in luminal A-like versus 63.5% in triple-negative versus 65.5% in HER2-positive and 69.7% in luminal B-like subtype). CONCLUSIONS: In young BRCA carriers, differences in recurrence pattern and second primary breast cancer among hormone receptor-positive versus negative disease warrant consideration in counseling patients on treatment, follow-up, and risk-reducing surgery.

2.
Phys Rev Lett ; 132(12): 122701, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38579210

RESUMO

^{140}Ce(n,γ) is a key reaction for slow neutron-capture (s-process) nucleosynthesis due to being a bottleneck in the reaction flow. For this reason, it was measured with high accuracy (uncertainty ≈5%) at the n_TOF facility, with an unprecedented combination of a high purity sample and low neutron-sensitivity detectors. The measured Maxwellian averaged cross section is up to 40% higher than previously accepted values. Stellar model calculations indicate a reduction around 20% of the s-process contribution to the Galactic cerium abundance and smaller sizeable differences for most of the heavier elements. No variations are found in the nucleosynthesis from massive stars.

3.
Drug Dev Ind Pharm ; 49(7): 448-455, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37394978

RESUMO

OBJECTIVE: To demonstrate the applicability of a novel micro-dosing system for precisely filling low powder doses (down to a few mg) into capsules along with weighing the filled powder mass accurately. METHODS: Ten commonly used pharmaceutical powders, ranging from cohesive to free-flowing, were selected and filled at three target fill weights (0.5, 1, and 10 mg), to investigate the effect of distinct powder properties on the filling performance. The fill weight and variability, filling speed and yield (% and number of conforming capsules out of all capsules collected), as well as the system's long-term performance were assessed. RESULTS: The filling accuracy was found to be good for all investigated powders. In particular, the results demonstrate that the tested powders, including the challenging cohesive ones, could be dosed at standard deviations within 0.23 mg at a 10 mg target weight, within 0.07 mg at a 1 mg target weight, and within 0.05 mg at a 0.5 mg target weight. In all cases, free-flowing powders showed lower standard deviations. Intermediate and cohesive powders had slightly higher standard deviations but were still within an acceptable range. CONCLUSION: The study shows the suitability of the tested micro-dosing system for filling low powder doses into capsules, which is of particular importance for dosing active pharmaceutical ingredients (APIs) directly in capsules, i.e. an API-in-capsule (AIC) approach for clinical trials (often in conjunction with highly potent APIs), and for low-dose powder filling for inhalation applications.


Assuntos
Tecnologia Farmacêutica , Tecnologia Farmacêutica/métodos , Pós , Cápsulas , Administração por Inalação , Composição de Medicamentos/métodos , Tamanho da Partícula
4.
Soc Psychiatry Psychiatr Epidemiol ; 57(5): 973-991, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35146551

RESUMO

PURPOSE: The service configuration with distinct child and adolescent mental health services (CAMHS) and adult mental health services (AMHS) may be a barrier to continuity of care. Because of a lack of transition policy, CAMHS clinicians have to decide whether and when a young person should transition to AMHS. This study describes which characteristics are associated with the clinicians' advice to continue treatment at AMHS. METHODS: Demographic, family, clinical, treatment, and service-use characteristics of the MILESTONE cohort of 763 young people from 39 CAMHS in Europe were assessed using multi-informant and standardized assessment tools. Logistic mixed models were fitted to assess the relationship between these characteristics and clinicians' transition recommendations. RESULTS: Young people with higher clinician-rated severity of psychopathology scores, with self- and parent-reported need for ongoing treatment, with lower everyday functional skills and without self-reported psychotic experiences were more likely to be recommended to continue treatment. Among those who had been recommended to continue treatment, young people who used psychotropic medication, who had been in CAMHS for more than a year, and for whom appropriate AMHS were available were more likely to be recommended to continue treatment at AMHS. Young people whose parents indicated a need for ongoing treatment were more likely to be recommended to stay in CAMHS. CONCLUSION: Although the decision regarding continuity of treatment was mostly determined by a small set of clinical characteristics, the recommendation to continue treatment at AMHS was mostly affected by service-use related characteristics, such as the availability of appropriate services.


Assuntos
Transtornos Mentais , Serviços de Saúde Mental , Adolescente , Adulto , Criança , Demografia , Família , Humanos , Transtornos Mentais/diagnóstico , Transtornos Mentais/epidemiologia , Transtornos Mentais/terapia , Pais
5.
Eur Phys J A Hadron Nucl ; 58(12): 239, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36514540

RESUMO

Neutron capture reaction cross sections on 74 Ge are of importance to determine 74 Ge production during the astrophysical slow neutron capture process. We present new resonance data on 74 Ge( n , γ ) reactions below 70 keV neutron energy. We calculate Maxwellian averaged cross sections, combining our data below 70 keV with evaluated cross sections at higher neutron energies. Our stellar cross sections are in agreement with a previous activation measurement performed at Forschungszentrum Karlsruhe by Marganiec et al., once their data has been re-normalised to account for an update in the reference cross section used in that experiment.

6.
Eur J Pediatr ; 179(5): 749-756, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31901982

RESUMO

Very rare tumors (VRTs) account for up to 11% of childhood cancers. Dedicated national groups and registries only exist in some European countries. Pleuropulmonary blastoma (PPB) is a very rare intrathoracic pediatric tumor with a potentially severe prognosis. Due to its rarity, it sometimes goes unrecognized. We investigated PPB diagnostic capability and possible correlations between diagnostic performance and VRT-dedicated activities. The number of cases of PPB registered between 2000 and 2014 at pediatric oncology centers in Europe was compared with the number of expected cases. Data sources included VRT registries, population-based cancer registries, and hospital registries. Data were obtained for 25 countries, grouped into 4 geographical regions. The expected cases were 111, and the observed cases were 129. The observed-to-expected ratio was 1.86 for Northern Europe, 1.33 for Southern Europe, 1.22 for Central Europe, and 0.65 for Eastern Europe. More cases than expected were registered in all countries with an official VRT registry.Conclusion: The number of cases observed is consistent with expectations, but disparities exist across Europe. Difficulties in diagnosing PPB emerged in most Eastern countries. The incidence rate of PPB may be underestimated. The creation of VRT-dedicated groups and a European Registry for VRTs could help to reduce inequalities.What is Known:• Very rare pediatric tumors are often not recognized, despite representing almost 11% of childhood cancers .• Pleuropulmonary blastoma is a rare pediatric tumor with a poor prognosis.What is New:• The ability to diagnose and register pleuropulmonary blastoma varies in Europe.Registries dedicated to very rare pediatric tumors improve the diagnostic rates.• The incidence rate of pleuropulmonary blastoma may currently be underestimated.


Assuntos
Neoplasias Pulmonares/epidemiologia , Blastoma Pulmonar/epidemiologia , Adolescente , Criança , Pré-Escolar , Estudos Transversais , Europa (Continente)/epidemiologia , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Neoplasias Pulmonares/diagnóstico , Masculino , Blastoma Pulmonar/diagnóstico , Sistema de Registros/estatística & dados numéricos , Estudos Retrospectivos
7.
Neoplasma ; 67(3): 684-691, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32182088

RESUMO

CyberKnife® Lung Optimized Treatment (LOT) allows the treatment of lung cancer without invasive fiducial implantation. The aim of this retrospective analysis was to evaluate the feasibility, toxicity and clinical outcome. One hundred fifteen patients (124 lesions) were treated with CyberKnife® using LOT. The median age was 72.6 years (range 31.8-90.3). From 124 treated lesions, 52 were with histopathological confirmation (41 primitive pulmonary cancers, 8 pulmonary metastases) and 72 as untyped tumors. For 5 patients (6 lesions) treatment was an in-field re-irradiation. Concomitant therapy was administered in 7 patients. Zero-View tracking was applied in 69 patients, 1-View in 33 patients, 2-View in 22 patients. The median total dose was 45 Gy (range 18-54), median dose/fraction was 15 Gy (range 4-18) with a median prescription isodose of 80% (range 68-85). The median planning target volume (PTV) was 25 cm3 (range 3-195). The median follow-up was 20 months (range 7-47). Thirty-seven patients (32%) were alive with no evidence of disease, 39 patients (34%) were alive with clinically evident disease, and 38 patients (33%) died of the disease. The 1- and 2-year overall survival (OS) rate was 83% and 61%. The median time to progression was 19 months (95% confidence interval: 11-19 months), 1- and 2-year progression-free survival (PFS) rates were 62% and 41%, respectively. Smaller PTV was significantly associated with better OS, PFS and in-field PFS in univariate and multivariate analyses. Acute toxicity was observed in 36 patients (41%). Late toxicity was registered in 25 patients (29%). G3 late toxicity was observed in one patient (1.1%). Our data suggest that fiducial less-stereotactic body radiation therapy (SBRT) is a feasible, well-tolerated and potentially effective treatment with high compliance in the setting of inoperable patients due to concomitant disease or previous treatments.


Assuntos
Neoplasias Pulmonares/radioterapia , Radiocirurgia/instrumentação , Adulto , Idoso , Idoso de 80 Anos ou mais , Fracionamento da Dose de Radiação , Estudos de Viabilidade , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento
8.
Eur J Neurol ; 26(3): 407-414, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30184312

RESUMO

BACKGROUND AND PURPOSE: The presence of a continuum between physiological déjà vu (DV) and epileptic DV is still not known as well as epidemiological data in the Italian population. The aim was to identify the epidemiological distribution of DV in Italy, and secondly to look for specific features of DV able to discriminate between epileptic and non-epileptic DV. METHODS: In all, 1000 individuals, 543 healthy controls (C) (313 women; age 40 ± 15 years) and 457 patients with epilepsy (E) (260 women; age 39 ± 14 years), were prospectively recruited from 10 outpatient neurological clinics throughout Italy. All populations were screened using the Italian Inventory for Déjà Vu Experiences Assessment (I-IDEA) test and E and pairwise C underwent a comprehensive epilepsy interview. RESULTS: Of E, 69% stated that they experienced 'recognition' and 13.2% reported that this feeling occurred from a few times a month to at least weekly (versus 7.7% of the control group). Furthermore, a greater percentage of E (6.8% vs. 2.2%) reported that from a few times a month to at least weekly they felt that it seemed as though everything around was not real. In E, the feeling of recognition raised fright (22.3% vs. 13.2%) and a sense of oppression (19.4% vs. 9.4%). A fifth of E felt recognition during epileptic seizures. CONCLUSION: Only E regardless of aetiology firmly answered that they had the feeling of recognition during an epileptic seizure; thus question 14 of the I-IDEA test part 2 discriminated E from C. Paranormal activity, remembering dreams and travel frequency were mostly correlated to DV in E suggesting that the visual-memory network might be involved in epileptic DV.


Assuntos
Déjà Vu , Epilepsia/fisiopatologia , Transtornos Neurocognitivos/fisiopatologia , Reconhecimento Psicológico/fisiologia , Adulto , Estudos de Coortes , Epilepsia/complicações , Epilepsia/epidemiologia , Feminino , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Transtornos Neurocognitivos/epidemiologia , Transtornos Neurocognitivos/etiologia
9.
J Radiol Prot ; 39(3): 906-919, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31216517

RESUMO

In this document we present the calculation and experimental validation of a source term for 18F-production with a cyclotron for medical applications operating at 18 MeV proton energy and 30 µA proton current. The Monte Carlo codes MCNP6 and FLUKA were used for the calculation of the source term. In addition, the radiation field around the 18O-enriched water target was simulated with the two codes. To validate the radiation field obtained in the simulation, an experimental program has been started using activation samples which are placed close to the water target during an 18F-production run of the cyclotron. After the irradiation, the samples are analysed and the resulting activation is compared to Monte Carlo calculations of the expected sample activation. We find good agreement between simulations and experimental results, with most calculation to experiment (C/E) ratios well between 0.6 and 1.4.


Assuntos
Ciclotrons , Radioisótopos de Flúor/química , Medicina Nuclear , Método de Monte Carlo , Nêutrons
10.
Reumatismo ; 71(2): 75-80, 2019 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-31309777

RESUMO

The objective was to determine the reduction of tophi in patients undergoing drug therapy in correlation with urate serum levels through ultrasound examination. A total of 31 male patients, between the ages of 33 to 77 years, with tophaceous gout were evaluated between 2005 and 2009, 11 of which were selected. Ultrasound examinations of visible tophi and evaluations of serum uric acids levels were performed annually on each patient. There was a statistically significant difference between measurements 1, 2, 3 and measurement 4 and between measurements 4 and 5. A strong significant positive association was seen between variation of tophus size and the reduction of serum uric acid levels.


Assuntos
Gota/sangue , Gota/diagnóstico por imagem , Ácido Úrico/sangue , Adulto , Idoso , Correlação de Dados , Gota/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
11.
Skin Res Technol ; 24(1): 9-15, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28543606

RESUMO

BACKGROUND: The differential diagnosis between regressing nevi and melanoma might be challenging; regressing areas can represent a confounding factor for the diagnosis and the histology still remain mandatory to rule out melanoma. Reflectance confocal microscopy may add valuable information by revealing features suggestive of the nature of the melanocytic proliferation. OBJECTIVE: To assess the impact of confocal microscopy in the management of regressive melanocytic lesions. METHODS: The dermoscopic analysis of 92 melanocytic lesions showing that more than 30% of regressions have been retrospectively considered, among them, 32 melanocytic lesions with a 7 check point list ≥3 they were assessed at the rcm and subsequently excised. For each selected lesion, dermoscopic features of regression (white scar-like areas, blue areas, blue white areas), distribution of regressing areas (central, peripheral, or both) and the percentage of regression have been examined by an expert in dermoscopy, blinded to the histological and confocal diagnosis. Subsequently, two experts in confocal microscopy revaluated, blinded from histology, RCM images. RESULTS: Of the 32 lesions analyzed, 23 (71.5%) were diagnosed histologically as nevi, and 9 (28.5%) as melanomas. 26 of 32 lesions (81.5%) exhibited regression >50% of the overall. On RCM, 11 lesions have been interpreted as malignant and 21 as benign. On RCM the majority of nevi exhibited regular architecture without cytological atypia. Epidermal disarray, pagetoid infiltration, disarranged dermo-epidermal junction architecture and atypical nests were considered as suspicious for malignancy. Good concordance between confocal readers has been detected. CONCLUSION: A combined dermoscopic/confocal approach can be used for the management of lesions exhibiting dermoscopic features of regression in order to provide a more conclusive pre-histological diagnosis avoiding a high number of unnecessary excisions. Limits of this study were represented by the relatively small number of lesions and the retrospective approach. Further, prospective studies on a larger number of cases, will be necessary in order to compare the efficacy of dermoscopy alone versus dermoscopy in combination with RCM for the evaluation of regression, suspected pigmented lesions.


Assuntos
Melanoma/diagnóstico , Nevo Pigmentado/diagnóstico , Neoplasias Cutâneas/diagnóstico , Dermoscopia/métodos , Diagnóstico Diferencial , Humanos , Melanoma/patologia , Microscopia Confocal/métodos , Nevo Pigmentado/patologia , Estudos Retrospectivos , Neoplasias Cutâneas/patologia
12.
Cytopathology ; 29(2): 196-200, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29205587

RESUMO

INTRODUCTION: FNA is a well-established method for the preoperative diagnosis of thyroid nodules, but limitations still reside among non-diagnostic and indeterminate samples. The objective of the present study was to assess the impact of repeat FNA in thyroid nodules primarily classified as non-diagnostic and indeterminate, with the evaluation of the diagnostic resolution rate after the reassessment of the nodule. METHODS: We retrospectively collected all cases of thyroid FNA at our institution in the last 5 years that had one or more repeat aspirations of the same nodule, calculating the percentage of samples with change in the diagnostic category. Additional collected data included sex, age and interval between the repeat aspirations. RESULTS: One hundred and seventy-eight specimens from 167 patients (140 female, 27 male) with a median age of 56 years (range 11-90) were included in the study. Among the 86 cases primarily classified as non-diagnostic, 25 (29.1%) remained in the same category after the first reassessment and only 18 (20.9%) after the second repeat aspiration. Among the 40 indeterminate cases, only 10 (25%) retained their status after the second aspiration, with no change after the third assessment. CONCLUSION: Repeat aspiration of non-diagnostic and indeterminate thyroid nodules had a positive impact in both groups, with diagnostic resolution rates of 80% and 75%, respectively. The present study therefore endorses the use of such strategy for the initial follow-up of nodules with no definite diagnosis, especially in low-resource centres with limited access to modern molecular technologies.


Assuntos
Nódulo da Glândula Tireoide/diagnóstico , Nódulo da Glândula Tireoide/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia por Agulha Fina , Criança , Feminino , Humanos , Masculino , Estudos Retrospectivos
15.
Int J Obes (Lond) ; 41(2): 289-298, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27795551

RESUMO

BACKGROUND/OBJECTIVES: In the last decade, a strict link between epigenetics and metabolism has been demonstrated. Histone deacetylases (HDACs) have emerged as key epigenetic regulators involved in metabolic homeostasis in normal and pathologic conditions. Here we investigated the effect of the class I HDAC inhibitor MS-275 in a model of obesity induced by a high-fat diet (HFD). METHODS: C57BL6/J male mice were fed HFD for 17 weeks and then randomized in two groups, treated intraperitoneally with vehicle dimethylsulfoxide (DMSO) or with the class I selective HDAC inhibitor MS-275 every other day for 22 days. Glucose tolerance test and measurement of body temperature during cold exposure were performed. Adipose tissues and liver were phenotypically characterized through histological analysis. Gene and protein expression analysis of brown and white adipose tissues (WATs) were performed. RESULTS: MS-275 treated mice showed 10% reduction of body weight, lower adipocyte size and improved glucose tolerance. Inhibition of class I HDAC determined reduction of adipocyte size and of fat mass, paralleled by higher expression of adipose functionality markers and by increased rate of lipolysis and fatty acid ß-oxidation. MS-275 also promoted thermogenic capacity, related to 'browning' of visceral and subcutaneous WAT, showing increased expression of uncoupling protein 1. In brown adipose tissue, we observed limited effects on gene expression and only reduction of brown adipocyte size. CONCLUSIONS: This study provides evidence that class I HDAC inhibition stimulated functionality and oxidative potential of adipose tissue, improving glucose tolerance and ameliorating the metabolic profile in diet-induced obese mice.


Assuntos
Adipócitos Marrons/efeitos dos fármacos , Tecido Adiposo Marrom/efeitos dos fármacos , Tecido Adiposo Branco/efeitos dos fármacos , Dieta Hiperlipídica/efeitos adversos , Inibidores de Histona Desacetilases/farmacologia , Obesidade/tratamento farmacológico , Obesidade/metabolismo , Adipócitos Marrons/metabolismo , Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Branco/metabolismo , Animais , Benzamidas/farmacologia , Modelos Animais de Doenças , Perfilação da Expressão Gênica , Teste de Tolerância a Glucose , Histona Desacetilases/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/enzimologia , Piridinas/farmacologia , Termogênese/efeitos dos fármacos , Termogênese/genética
16.
Strahlenther Onkol ; 193(11): 971-981, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28884310

RESUMO

PURPOSE: Acute toxicity in head and neck (H&N) cancer patients treated with definitive radiotherapy (RT) has a crucial role in compliance to treatments. The aim of this study was to correlate doses to swallowing-associated structures and acute dysphagia. METHODS: We prospectively analyzed 42 H&N cancer patients treated with RT. Dysphagia (grade ≥ 3) and indication for percutaneous endoscopic gastrostomy (PEG) insertion were classified as acute toxicity. Ten swallowing-related structures were considered for the dosimetric analysis. The correlation between clinical information and the dose absorbed by the contoured structures was analyzed. Multivariate logistic regression method using resampling methods (bootstrapping) was applied to select model order and parameters for normal tissue complication probability (NTCP) modelling. RESULTS: A strong multiple correlation between dosimetric parameters was found. A two-variable model was suggested as the optimal order by bootstrap method. The optimal model (Rs = 0.452, p < 0.001) includes V45 of the cervical esophagus (odds ratio [OR] = 1.016) and Dmean of the cricopharyngeal muscle (OR = 1.057). The model area under the curve was 0.82 (95% confidence interval 0.69-0.95). CONCLUSION: Our results suggested that the absorbed dose to the cricopharyngeal muscle and cervical esophagus might play a relevant role in the development of acute RT-related dysphagia.


Assuntos
Carcinoma de Células Escamosas/radioterapia , Transtornos de Deglutição/etiologia , Deglutição/efeitos da radiação , Neoplasias Otorrinolaringológicas/radioterapia , Lesões por Radiação/etiologia , Adulto , Idoso , Transtornos de Deglutição/terapia , Nutrição Enteral , Esôfago/efeitos da radiação , Feminino , Gastrostomia , Humanos , Masculino , Pessoa de Meia-Idade , Músculos Faríngeos/efeitos da radiação , Estudos Prospectivos , Lesões por Radiação/terapia , Dosagem Radioterapêutica , Estatística como Assunto
17.
J Dairy Sci ; 100(6): 4961-4975, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28365121

RESUMO

Negative energy balance in dairy cows in early lactation has been associated with increased inflammation and oxidative stress in these cows. The objective of this study was to evaluate the effects of dry period (DP) length and dietary energy source on inflammatory biomarkers and oxidative stress in dairy cows. Holstein-Friesian dairy cows (60 primiparous and 107 multiparous) were assigned randomly to a 3 × 2 factorial design with 3 DP length (0, 30, or 60 d) and 2 early lactation rations (glucogenic or lipogenic). Cows were fed a glucogenic or lipogenic ration from 10 d before the expected calving date. Blood was collected in wk -3, -2, -1, 1, 2, and 4 relative to calving. Dry period length affected inflammatory biomarkers and oxidative stress, especially in wk 1 and 2 after calving. Cows with a 0-d DP had higher levels of ceruloplasmin, cholesterol, and reactive oxygen metabolites, and they tended to have higher haptoglobin levels compared with cows with a 30- or 60-d DP. Cows with a 0-d DP had a lower plasma paraoxonase and bilirubin in the first 2 wk after calving and a lower liver functionality index compared with cows with a 60-d DP. Cows of parity >3 fed a glucogenic ration had higher cholesterol levels compared with cows of parity >3 fed a lipogenic ration. No interaction between DP length and ration was present for inflammatory biomarkers or oxidative stress variables. Plasma bilirubin levels for cows with a 0-d DP were negatively related to energy balance and metabolic status in these cows. Moreover, occurrence of clinical health problems (fever, mastitis, metritis, and retained placenta) was 41, 27, and 30% for cows with 0-, 30-, and 60-d DP, respectively. High levels of ceruloplasmin, cholesterol, and reactive oxygen metabolites in cows with 0-d DP were related to the occurrence of health problems in these cows. In conclusion, omitting the DP increased levels of ceruloplasmin, cholesterol, and reactive oxygen metabolites, and decreased levels of bilirubin and paraoxonase in plasma, independent of ration, compared with cows with a 60-d DP. These contrasting effects of DP length on inflammatory status could be explained in part by the improved energy balance and occurrence of health problems in these cows, but was not related to increased somatic cell count in cows with a 0-d DP. Cows with a 0-d DP had better energy balance, but also had higher levels of oxidative stress compared with cows with a 60-d DP. Moreover, occurrence of health problems did not differ between cows with different DP lengths.


Assuntos
Biomarcadores/sangue , Ingestão de Energia , Metabolismo Energético/fisiologia , Estresse Oxidativo , Ração Animal , Animais , Arildialquilfosfatase/sangue , Bilirrubina/sangue , Bovinos , Doenças dos Bovinos/sangue , Ceruloplasmina/análise , Colesterol/sangue , Dieta , Dieta Hiperlipídica/veterinária , Feminino , Haptoglobinas/análise , Lactação , Gravidez , Espécies Reativas de Oxigênio/sangue , Fatores de Tempo
18.
Nano Lett ; 16(1): 8-20, 2016 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-26666842

RESUMO

The combination of plasmonic nanoparticles and graphene enhances the responsivity and spectral selectivity of graphene-based photodetectors. However, the small area of the metal-graphene junction, where the induced electron-hole pairs separate, limits the photoactive region to submicron length scales. Here, we couple graphene with a plasmonic grating and exploit the resulting surface plasmon polaritons to deliver the collected photons to the junction region of a metal-graphene-metal photodetector. This gives a 400% enhancement of responsivity and a 1000% increase in photoactive length, combined with tunable spectral selectivity. The interference between surface plasmon polaritons and the incident wave introduces new functionalities, such as light flux attraction or repulsion from the contact edges, enabling the tailored design of the photodetector's spectral response. This architecture can also be used for surface plasmon biosensing with direct-electric-redout, eliminating the need of bulky optics.


Assuntos
Técnicas Biossensoriais , Grafite/química , Metais/química , Nanopartículas/química , Luz , Nanotecnologia/métodos , Fótons , Ressonância de Plasmônio de Superfície
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