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1.
J Endocrinol Invest ; 44(8): 1679-1688, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33460012

RESUMO

PURPOSE: Evidence of an increased diagnostic pressure on thyroid has emerged over the past decades. This study aimed to provide estimates of a wide spectrum of surveillance indicators for thyroid dysfunctions and diseases in Italy. METHODS: A population-based study was conducted in North-eastern Italy, including 11.7 million residents (20% of the total Italian population). Prescriptions for TSH testing, neck ultrasound or thyroid fine needle aspiration (FNA), surgical procedures, and drugs for hypo- or hyperthyroidism were extracted from regional health databases. Proportions and rates of selected examinations were calculated from 2010 to 2017, overall and by sex, calendar years, age, and region. RESULTS: Between 2010 and 2017 in North-eastern Italy, 24.5% of women and 9.8% of men received at least one TSH test yearly. In 2017, 7.1% of women and 1.5% of men were prescribed drugs for thyroid dysfunction, 94.6% of whom for hypothyroidism. Neck ultrasound examinations were performed yearly in 6.9% of women and 4.6% of men, with a nearly two-fold variation between areas. Thyroid FNA and thyroidectomies were three-fold more frequent in women (394 and 85 per 100,000) than in men (128 and 29 per 100,000) with a marked variation between areas. Both procedures decreased consistently after 2013. CONCLUSIONS: The results of this population-based study describe recent variations over time and between surrounding areas of indicators of 'diagnostic pressure' on thyroid in North-eastern Italy. These results emphasize the need to harmonize practices and to reduce some procedures (e.g., neck ultrasound and total thyroidectomies) in certain areas.


Assuntos
Biópsia por Agulha Fina , Doenças da Glândula Tireoide , Testes de Função Tireóidea , Glândula Tireoide , Tireoidectomia , Ultrassonografia , Adulto , Idoso , Biópsia por Agulha Fina/métodos , Biópsia por Agulha Fina/tendências , Feminino , Humanos , Itália/epidemiologia , Masculino , Uso Excessivo dos Serviços de Saúde/prevenção & controle , Uso Excessivo dos Serviços de Saúde/tendências , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Vigilância da População , Fatores Sexuais , Doenças da Glândula Tireoide/diagnóstico , Doenças da Glândula Tireoide/epidemiologia , Doenças da Glândula Tireoide/cirurgia , Testes de Função Tireóidea/métodos , Testes de Função Tireóidea/tendências , Glândula Tireoide/diagnóstico por imagem , Glândula Tireoide/patologia , Tireoidectomia/métodos , Tireoidectomia/tendências , Ultrassonografia/métodos , Ultrassonografia/tendências
2.
J Transl Med ; 17(1): 187, 2019 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-31159827

RESUMO

BACKGROUND: Tumors develop by progression through a series of stages. Every cell of the tumor microenvironment is constantly changing in the flow of the cancer progression. It has become clear in recent years that stroma is essential for tumor maintenance and growth. Here, we aimed to give a chronological order of gene expression changes given in the dynamical framework of microinvasive breast cancer microenvironment. METHODS: RNA-seq was performed on seven microinvasive breast cancers. For each of them we microdissected seven different portions of the tumor, four related to the breast epithelium and three to the stroma. Breast epithelium was chronologically subdivided in normal breast epithelium (NBE), carcinoma in situ (CIS), emerging invasive fingers (EIF) and invasive breast cancer (IBC). For each of the breast epithelium subdivisions we collected the adjacent stroma (S): S-NBE, S-EIF and S-IBC. RESULTS: The overall differentially expressed genes (DEGs) in all the compartments were analysed and evaluated to understand the pathways involved in tumor progression. Then we analysed the DEGs of the epithelial and stromal portions in comparison with the normal portions. We observed that the stromal cells are necessary for the development and the maintenance of the tumor, especially in tumor progression. Moreover the most important genes involved in the main metabolic pathways were analysed and the communications within the different cell compartments were highlighted. CONCLUSIONS: As a future perspective, a deeply study of the identified key genes, particularly in the stromal cells, will be crucial to develop an anticancer therapy that is undergoing a conversion from a cancer cell-centric strategy to a stroma-centric strategy, more genomically stable.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Carcinoma Intraductal não Infiltrante/genética , Carcinoma Intraductal não Infiltrante/patologia , Microambiente Tumoral/genética , Mama/metabolismo , Mama/patologia , Progressão da Doença , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Redes e Vias Metabólicas/genética , Invasividade Neoplásica , Estadiamento de Neoplasias , Análise de Sequência de RNA , Células Estromais/patologia
3.
Nano Lett ; 18(8): 4861-4865, 2018 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-29995419

RESUMO

We report experimental evidence of ballistic hole transport in one-dimensional quantum wires gate-defined in a strained SiGe/Ge/SiGe quantum well. At zero magnetic field, we observe conductance plateaus at integer multiples of 2 e2/ h. At finite magnetic field, the splitting of these plateaus by Zeeman effect reveals largely anisotropic g-factors with absolute values below 1 in the quantum-well plane, and exceeding 10 out-of-plane. This g-factor anisotropy is consistent with a heavy-hole character of the propagating valence-band states, which is in line with a predominant confinement in the growth direction. Remarkably, we observe quantized ballistic conductance in device channels up to 600 nm long. These findings mark an important step toward the realization of novel devices for applications in quantum spintronics.

4.
Nano Lett ; 16(1): 88-92, 2016 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-26599868

RESUMO

Hole spins in silicon represent a promising yet barely explored direction for solid-state quantum computation, possibly combining long spin coherence, resulting from a reduced hyperfine interaction, and fast electrically driven qubit manipulation. Here we show that a silicon-nanowire field-effect transistor based on state-of-the-art silicon-on-insulator technology can be operated as a few-hole quantum dot. A detailed magnetotransport study of the first accessible hole reveals a g-factor with unexpectedly strong anisotropy and gate dependence. We infer that these two characteristics could enable an electrically driven g-tensor-modulation spin resonance with Rabi frequencies exceeding several hundred mega-Hertz.

5.
J Microencapsul ; 34(2): 162-170, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28345377

RESUMO

The association chitosan/linoleic acid/lactobionic acid in aqueous solution spontaneously led to the formation of stable microparticles with a liquid hydrophobic core consisting of linoleic acid surrounded by a shell of chitosan/lactobionic acid. The originality of the microparticles arises from the fact that they are formed by the association of three ingredients of cosmetic interest, including a skin penetration enhancer (linoleic acid). Dynamic light scattering (DLS) measurements showed microparticles with a mean diameter of 1-2 µm. The presence of a hydrophobic liquid core was observed by transmission electron microscopy (TEM). The ability of these microparticles to encapsulate phenylethyl resorcinol, a hydrophobic skin lightener, was evaluated and its encapsulation was confirmed thanks to T2 measurements and nuclear Overhauser effects (nOe) signs.


Assuntos
Quitosana/química , Cosméticos/química , Dissacarídeos/química , Ácido Linoleico/química , Tamanho da Partícula
6.
Ann Oncol ; 27(8): 1619-25, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27234641

RESUMO

BACKGROUND: Poor oral hygiene has been proposed to contribute to head and neck cancer (HNC) risk, although causality and independency of some indicators are uncertain. This study investigates the relationship of five oral hygiene indicators with incident HNCs. METHODS: In a pooled analysis of 8925 HNC cases and 12 527 controls from 13 studies participating in the International Head and Neck Cancer Epidemiology Consortium, comparable data on good oral hygiene indicators were harmonized. These included: no denture wear, no gum disease (or bleeding), <5 missing teeth, tooth brushing at least daily, and visiting a dentist ≥once a year. Logistic regression was used to estimate the effects of each oral hygiene indicator and cumulative score on HNC risk, adjusting for tobacco smoking and alcohol consumption. RESULTS: Inverse associations with any HNC, in the hypothesized direction, were observed for <5 missing teeth [odds ratio (OR) = 0.78; 95% confidence interval (CI) 0.74, 0.82], annual dentist visit (OR = 0.82; 95% CI 0.78, 0.87), daily tooth brushing (OR = 0.83, 95% CI 0.79, 0.88), and no gum disease (OR = 0.94; 95% CI 0.89, 0.99), and no association was observed for wearing dentures. These associations were relatively consistent across specific cancer sites, especially for tooth brushing and dentist visits. The population attributable fraction for ≤ 2 out of 5 good oral hygiene indicators was 8.9% (95% CI 3.3%, 14%) for oral cavity cancer. CONCLUSION: Good oral hygiene, as characterized by few missing teeth, annual dentist visits, and daily tooth brushing, may modestly reduce the risk of HNC.


Assuntos
Neoplasias de Cabeça e Pescoço/epidemiologia , Neoplasias Bucais/epidemiologia , Higiene Bucal , Adulto , Idoso , Consumo de Bebidas Alcoólicas/efeitos adversos , Feminino , Neoplasias de Cabeça e Pescoço/etiologia , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/prevenção & controle , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/etiologia , Neoplasias Bucais/patologia , Neoplasias Bucais/prevenção & controle , Fatores de Risco , Fumar/efeitos adversos
7.
J Neurooncol ; 126(2): 265-70, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26511493

RESUMO

Glioblastoma is the most common and aggressive malignant primary brain tumor. Despite decades of research and the advent of new therapies, patients with glioblastoma continue to have a very poor prognosis. Radiation therapy has a major role as adjuvant treatment for glioblastoma following surgical resection. Many studies have shown that polymorphisms of genes involved in pathways of DNA repair may affect the sensitivity of the cells to treatment. Although the role of these polymorphisms has been investigated in relation to response to radiotherapy, their role as predisposing factors to glioblastoma has not been clarified yet. In the present study, we evaluated the association between polymorphisms in DNA repair genes, namely: XRCC1 rs25487, XRCC3 rs861539 and RAD51 rs1801320, with the susceptibility to develop glioblastoma. Eighty-five glioblastoma patients and 70 matched controls were recruited for this study. Data from the 1000 Genomes Project (98 Tuscans) were also downloaded and used for the association analysis. Subjects carrying RAD51 rs1801320 GC genotype showed an increased risk of glioblastoma (GC vs GG, χ(2) = 10.75; OR 3.0087; p = 0.0010). The C allele was also significantly associated to glioblastoma (χ(2) = 8.66; OR 2.5674; p = 0.0032). Moreover, RAD51 rs1801320 C allele increased the risk to develop glioblastoma also when combined to XRCC1 rs25487 G allele and XRCC3 rs861539 C allele (χ(2) = 6.558; p = 0.0053).


Assuntos
Neoplasias Encefálicas/genética , Reparo do DNA , Glioblastoma/genética , Polimorfismo de Nucleotídeo Único , Rad51 Recombinase/genética , Idoso , Proteínas de Ligação a DNA/genética , Feminino , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Proteína 1 Complementadora Cruzada de Reparo de Raio-X
8.
Br J Cancer ; 110(1): 7-11, 2014 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-24300979

RESUMO

In the last three decades, the appreciation of the role of infections in cancer aetiology has greatly expanded. Among the 13 million new cancer cases that occurred worldwide in 2008, around 2 million (16%) were attributable to infections. Concurrently, the approach to prevention of infection-related cancers is shifting from cancer control to infection control, for example, vaccination and the detection of infected individuals. In support of this change, the use of infection transmission models has entered the field of infection-related cancer epidemiology. These models are useful to understand the infection transmission processes, to estimate the key parameters that govern the spread of infection, and to project the potential impact of different preventive measures. However, the concepts, terminology, and methods used to study infection transmission are not yet well known in the domain of cancer epidemiology. This review aims to concisely illustrate the main principles of transmission dynamics, the basic structure of infection transmission models, and their use in combination with empirical data. We also briefly summarise models of carcinogenesis and discuss their specificities and possible integration with models of infection natural history.


Assuntos
Infecções/epidemiologia , Infecções/transmissão , Modelos Estatísticos , Neoplasias/epidemiologia , Neoplasias/microbiologia , Doença Crônica/epidemiologia , Métodos Epidemiológicos , Humanos
9.
Br J Cancer ; 111(5): 965-9, 2014 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-24992581

RESUMO

BACKGROUND: Nordic countries' data offer a unique possibility to evaluate the long-term benefit of cervical cancer screening in a context of increasing risk of human papillomavirus infection. METHODS: Ad hoc-refined age-period-cohort models were applied to the last 50-year incidence data from Denmark, Finland, Norway and Sweden to project expected cervical cancer cases in a no-screening scenario. RESULTS: In the absence of screening, projected incidence rates for 2006-2010 in Nordic countries would have been between 3 and 5 times higher than observed rates. Over 60,000 cases or between 41 and 49% of the expected cases of cervical cancer may have been prevented by the introduction of screening in the late 1960s and early 1970s. CONCLUSIONS: Our study suggests that screening programmes might have prevented a HPV-driven epidemic of cervical cancer in Nordic countries. According to extrapolations from cohort effects, cervical cancer incidence rates in the Nordic countries would have been otherwise comparable to the highest incidence rates currently detected in low-income countries.


Assuntos
Neoplasias do Colo do Útero/epidemiologia , Detecção Precoce de Câncer/métodos , Feminino , Finlândia/epidemiologia , Humanos , Incidência , Programas de Rastreamento/métodos , Infecções por Papillomavirus/epidemiologia , Países Escandinavos e Nórdicos/epidemiologia , Neoplasias do Colo do Útero/virologia
10.
Br J Cancer ; 108(1): 240-4, 2013 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-23169278

RESUMO

BACKGROUND: Factors that favour a small proportion of HPV16 infections to progress to cancer are still poorly understood, but several studies have implicated a role of HPV16 genetic variation. METHODS: To evaluate the association between HPV16 genetic variants and cervical cancer risk, we designed a multicentre case-control study based on HPV16-positive cervical samples (1121 cervical cancer cases and 400 controls) from the International Agency for Research on Cancer biobank. By sequencing the E6 gene, HPV16 isolates were classified into variant lineages and the European (EUR)-lineage isolates were subclassified by the common polymorphism T350G. RESULTS: Incidence of variant lineages differed between cases and controls in Europe/Central Asia (P=0.006, driven by an underrepresentation of African lineages in cases), and South/Central America (P=0.056, driven by an overrepresentation of Asian American/North American lineages in cases). EUR-350G isolates were significantly underrepresented in cervical cancer in East Asia (odds ratio (OR)=0.02 vs EUR-350T; 95% confidence interval (CI)=0.00-0.37) and Europe/Central Asia (OR=0.42; 95% CI=0.27-0.64), whereas the opposite was true in South/Central America (OR=4.69; 95% CI=2.07-10.66). CONCLUSION: We observed that the distribution of HPV16 variants worldwide, and their relative risks for cervical cancer appear to be population-dependent.


Assuntos
Variação Genética , Papillomavirus Humano 16/genética , Infecções por Papillomavirus/genética , Neoplasias do Colo do Útero/epidemiologia , Estudos de Casos e Controles , DNA Viral , Feminino , Humanos , Infecções por Papillomavirus/epidemiologia , Polimorfismo Genético , Vigilância da População , Risco
11.
Br J Cancer ; 108(1): 222-8, 2013 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-23169288

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) has been associated to diabetes and obesity, but a possible association with the metabolic syndrome (MetS) and its potential interaction with hepatitis is open to discussion. METHODS: We analysed data from an Italian case-control study, including 185 HCC cases and 404 controls. Odds ratios (ORs) and 95% confidence intervals (CIs) were computed from unconditional logistic regression models. RESULTS: Among the MetS components, diabetes and obesity (i.e, body mass index (BMI)≥30 kg m(-2)) were positively associated to HCC risk, with ORs of 4.33 (95% CI, 1.89-9.86) and 1.97 (95% CI, 1.03-3.79), respectively. The ORs for the MetS were 4.06 (95% CI, 1.33-12.38) defining obesity as BMI≥25, and 1.92 (95% CI, 0.38-9.76) defining it as BMI≥30. The risk increased with the number of MetS components, up to an almost four-fold excess risk among subjects with ≥2 MetS factors. Among subjects without chronic infection with hepatitis B and/or C, the OR for those with ≥2 MetS components was over six-fold elevated. There was no consistent association in subjects with serological evidence of hepatitis B and/or C infection. CONCLUSION: This study found that the risk of HCC increases with the number of MetS components in subjects not chronically infected with hepatitis viruses.


Assuntos
Carcinoma Hepatocelular/epidemiologia , Neoplasias Hepáticas/epidemiologia , Síndrome Metabólica/epidemiologia , Idoso , Estudos de Casos e Controles , Diabetes Mellitus/epidemiologia , Feminino , Hepatite/epidemiologia , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Obesidade
12.
Ann Oncol ; 24(12): 3094-9, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24155133

RESUMO

BACKGROUND: Carbohydrate foods with high glycemic and insulinemic potential may influence cancer risk possibly through the insulin/growth-factor axis. Two staple carbohydrate foods of the Mediterranean diet, bread and pasta, have different glycemic and insulinemic responses and hence may affect cancer risk differently. MATERIALS AND METHODS: We studied the association of bread and pasta with breast and colorectal cancer risk using data from two Italian case-control studies. These studies included 2569 women with histologically confirmed breast cancer and 1953 men and women with colorectal cancer. Controls were 2588 and 4154, respectively, admitted to the same hospitals as cases for acute, non-neoplastic conditions. Multivariate odds ratios (ORs) were obtained after allowance for relevant confounding factors. RESULTS: The ORs of breast cancer for the highest versus the lowest quintile were 1.28 (95% confidence interval, CI: 1.03-1.58, P-trend = 0.0342) for bread and 1.07 (95% CI: 0.88-1.31, P-trend = 0.7072) for pasta. The association with bread remained virtually unchanged with postmenopause and overweight. The ORs of colorectal cancer in women for the highest versus the lowest quintile were 2.02 (95% CI: 1.46-2.80, P-trend = 0.0002) for bread and 1.37 (95% CI: 1.00-1.88, P-trend = 0.0164) for pasta. The associations remained significant only for bread in strata of menopausal status and in women with overweight. No significant associations were seen in men for either bread or pasta. CONCLUSIONS: Overall, these two cancer case-control studies showed stronger positive associations with bread than pasta in women, particularly if overweight, suggesting possible hormonal-related mechanisms.


Assuntos
Pão/efeitos adversos , Neoplasias da Mama/etiologia , Neoplasias Colorretais/etiologia , Carboidratos da Dieta/efeitos adversos , Idoso , Índice de Massa Corporal , Estudos de Casos e Controles , Dieta Mediterrânea , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Fatores de Risco
13.
Ann Oncol ; 24(10): 2651-2656, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23884440

RESUMO

BACKGROUND: The risk of many cancers is higher in subjects with a family history (FH) of cancer at a concordant site. However, few studies investigated FH of cancer at discordant sites. PATIENTS AND METHODS: This study is based on a network of Italian and Swiss case-control studies on 13 cancer sites conducted between 1991 and 2009, and including more than 12 000 cases and 11 000 controls. We collected information on history of any cancer in first degree relatives, and age at diagnosis. Odds ratios (ORs) for FH were calculated by multiple logistic regression models, adjusted for major confounding factors. RESULTS: All sites showed an excess risk in relation to FH of cancer at the same site. Increased risks were also found for oral and pharyngeal cancer and FH of laryngeal cancer (OR = 3.3), esophageal cancer and FH of oral and pharyngeal cancer (OR = 4.1), breast cancer and FH of colorectal cancer (OR = 1.5) and of hemolymphopoietic cancers (OR = 1.7), ovarian cancer and FH of breast cancer (OR = 2.3), and prostate cancer and FH of bladder cancer (OR = 3.4). For most cancer sites, the association with FH was stronger when the proband was affected at age <60 years. CONCLUSIONS: Our results point to several potential cancer syndromes that appear among close relatives and may indicate the presence of genetic factors influencing multiple cancer sites.


Assuntos
Saúde da Família , Neoplasias/epidemiologia , Estudos de Casos e Controles , Feminino , Predisposição Genética para Doença , Humanos , Itália/epidemiologia , Masculino , Neoplasias/genética , Risco , Fatores de Risco , Inquéritos e Questionários , Suíça/epidemiologia
14.
Ann Oncol ; 24(12): 3107-12, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24121119

RESUMO

BACKGROUND: Consumption of red meat has been related to increased risk of several cancers. Cooking methods could modify the magnitude of this association, as production of chemicals depends on the temperature and duration of cooking. METHODS: We analyzed data from a network of case-control studies conducted in Italy and Switzerland between 1991 and 2009. The studies included 1465 oral and pharyngeal, 198 nasopharyngeal, 851 laryngeal, 505 esophageal, 230 stomach, 1463 colon, 927 rectal, 326 pancreatic, 3034 breast, 454 endometrial, 1031 ovarian, 1294 prostate and 767 renal cancer cases. Controls included 11 656 patients admitted for acute, non-neoplastic conditions. Odds ratios (ORs) and confidence intervals (CIs) were estimated by multiple logistic regression models, adjusted for known confounding factors. RESULTS: Daily intake of red meat was significantly associated with the risk of cancer of the oral cavity and pharynx (OR for increase of 50 g/day = 1.38; 95% CI: 1.26-1.52), nasopharynx (OR = 1.29; 95% CI: 1.04-1.60), larynx (OR = 1.46; 95% CI: 1.30-1.64), esophagus (OR = 1.46; 95% CI: 1.23-1.72), colon (OR = 1.17; 95% CI: 1.08-1.26), rectum (OR = 1.22; 95% CI:1.11-1.33), pancreas (OR = 1.51; 95% CI: 1.25-1.82), breast (OR = 1.12; 95% CI: 1.04-1.19), endometrium (OR = 1.30; 95% CI: 1.10-1.55) and ovary (OR = 1.29; 95% CI: 1.16-1.43). Fried meat was associated with a higher risk of cancer of oral cavity and pharynx (OR = 2.80; 95% CI: 2.02-3.89) and esophagus (OR = 4.52; 95% CI: 2.50-8.18). Risk of prostate cancer increased for meat cooked by roasting/grilling (OR = 1.31; 95% CI: 1.12-1.54). No heterogeneity according to cooking methods emerged for other cancers. Nonetheless, significant associations with boiled/stewed meat also emerged for cancer of the nasopharynx (OR = 1.97; 95% CI: 1.30-3.00) and stomach (OR = 1.86; 95% CI: 1.20-2.87). CONCLUSIONS: Our analysis confirmed red meat consumption as a risk factor for several cancer sites, with a limited impact of cooking methods. These findings, thus, call for a limitation of its consumption in populations of Western countries.


Assuntos
Carne/efeitos adversos , Neoplasias/etiologia , Idoso , Estudos de Casos e Controles , Culinária , Dieta , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
15.
Phys Rev Lett ; 110(13): 136802, 2013 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-23581354

RESUMO

We report on microwave-driven coherent electron transfer between two coupled donors embedded in a silicon nanowire. By increasing the microwave frequency we observe a transition from incoherent to coherent driving revealed by the emergence of a Landau-Zener-Stückelberg quantum interference pattern of the measured current through the donors. This interference pattern is fitted to extract characteristic parameters of the double-donor system. In particular we estimate a charge dephasing time of 0.3±0.1 ns, comparable to other types of charge-based two-level systems. The demonstrated coherent coupling between two dopants is an important step towards donor-based quantum computing devices in silicon.

16.
Phys Rev Lett ; 110(4): 046602, 2013 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-25166183

RESUMO

We report an electric-field-induced giant modulation of the hole g factor in SiGe nanocrystals. The observed effect is ascribed to a so-far overlooked contribution to the g factor that stems from the mixing between heavy- and light-hole wave functions. We show that the relative displacement between the confined heavy- and light-hole states, occurring upon application of the electric field, alters their mixing strength leading to a strong nonmonotonic modulation of the g factor.

17.
Br J Cancer ; 107(9): 1445-50, 2012 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-22955856

RESUMO

Vaccines against the human papillomaviruses (HPV) that cause around 70% of cervical cancer cases worldwide are highly efficacious when administered before infection with the viruses, which occurs soon after initiation of sexual activity. Despite recommendations from key public health bodies that the primary target population for HPV vaccination should be young adolescent girls, numerous articles have suggested widening the target age group to include older adolescent girls and adult women. These articles cite evidence of efficacy and cost-effectiveness when making recommendations, and they rarely take into account the difficult resource-allocation issues faced by decision makers in low-income countries. Authors and sponsors of these articles are usually from high-income countries and sometimes include vaccine manufacturers. This review discusses the strengths and weaknesses of several types of evidence offered by these papers in support of vaccination of a broad age range of girls and women. It concludes that the greatest public health benefit and value for resources will come from vaccinating girls before sexual debut and exposure to HPV, particularly in low-resource areas.


Assuntos
Infecções por Papillomavirus/prevenção & controle , Vacinas contra Papillomavirus/administração & dosagem , Neoplasias do Colo do Útero/prevenção & controle , Neoplasias do Colo do Útero/virologia , Adolescente , Adulto , Análise Custo-Benefício , Países em Desenvolvimento , Feminino , Humanos , Infecções por Papillomavirus/economia , Infecções por Papillomavirus/virologia , Vacinas contra Papillomavirus/economia , Comportamento Sexual , Neoplasias do Colo do Útero/economia , Adulto Jovem
18.
Br J Cancer ; 106(1): 222-6, 2012 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-22116302

RESUMO

BACKGROUND: The association of transitional cell carcinomas of the bladder (TCB) with Schistosoma haematobium suggested a possible role of infections in the aetiology of TCB. METHODS: In all, 114 TCB cases and 140 hospital controls from Pordenone Province were enrolled within an Italian multi-centric case-control study. Urine samples were screened for DNA from five human polyomaviruses (HPyV) (JCV, BKV, MCV, WUV, and KIV); SV40; and 22 mucosal human papillomaviruses (HPV) using highly sensitive PCR assays. Odds ratios (ORs) and corresponding confidence intervals (CIs) were computed for risk of TCB by HPyV- or HPV-positivity using unconditional logistic regression. RESULTS: Human polyomavirus prevalence was similar in TCB cases (71.7%) and controls (77.7%) (OR for TCB=0.85; 95% CI: 0.45-1.61). JCV was the most frequently detected HPyV type. No individual HPyV showed a significant association. Among cases, HPyV-positivity was not associated with tumour characteristics, but it was significantly lower in women than men and among current and former smokers than never smokers. Human papillomavirus was detected in seven cases and five controls (OR=1.52; 95% CI: 0.42-5.45). CONCLUSION: The present small study does not support an involvement of HPyV or HPV infection in TCB aetiology in immunocompetent individuals. Differences in HPyV-positivity by sex and smoking may derive from differences in either acquisition or persistence of the infection.


Assuntos
Carcinoma de Células de Transição/complicações , Infecções por Papillomavirus/urina , Infecções por Polyomavirus/urina , Neoplasias da Bexiga Urinária/complicações , Idoso , Feminino , Humanos , Masculino , Infecções por Papillomavirus/complicações , Reação em Cadeia da Polimerase , Infecções por Polyomavirus/complicações , Fatores de Risco
19.
Br J Cancer ; 107(9): 1624-30, 2012 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-23033006

RESUMO

BACKGROUND: We assessed the association of human papillomavirus (HPV) infection and cervical intraepithelial neoplasia (CIN) with various characteristics, CD4 count and use of combination antiretroviral therapy (cART) among HIV-positive women. METHODS: Cross-sectional study of 498 HIV-positive women who underwent HPV PCR-based testing, cytology, and systematic cervical biopsy. RESULTS: In all, 68.7% of women were HPV-positive, 52.6% had high-risk (hr) HPV, and 40.2% multiple type infections. High-risk human papillomavirus-positivity did not vary significantly by age but it was negatively associated with education level. The most frequent types in 113 CIN2/3 were HPV16 (26.5%), HPV35 (19.5%), and HPV58 (12.4%). CD4 count was negatively associated with prevalence of hrHPV (P<0.001) and CIN2/3 among non-users of cART (P=0.013). Combination antiretroviral therapies users (≥2 year) had lower hrHPV prevalence (prevalence ratio (PR) vs non-users=0.77, 95% confidence interval (CI): 0.61-0.96) and multiple infections (PR=0.68, 95% CI: 0.53-0.88), but not fewer CIN2/3. The positive predictive value of hrHPV-positivity for CIN2/3 increased from 28.9% at age <35 years to 53.3% in ≥45 years. CONCLUSION: The burden of hrHPV and CIN2/3 was high and it was related to immunosuppression level. Combination antiretroviral therapies ( ≥2 year) use had a favourable effect on hrHPV prevalence but cART in our population may have been started too late to prevent CIN2/3.


Assuntos
Infecções por HIV/epidemiologia , Infecções por Papillomavirus/epidemiologia , Displasia do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/epidemiologia , Adulto , Estudos de Coortes , Estudos Transversais , Feminino , Infecções por HIV/virologia , Humanos , Quênia/epidemiologia , Pessoa de Meia-Idade , Infecções por Papillomavirus/virologia , Prevalência , Neoplasias do Colo do Útero/virologia , Displasia do Colo do Útero/virologia
20.
Br J Cancer ; 107(9): 1580-3, 2012 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-22968647

RESUMO

BACKGROUND: Dietary habits have been related to the risk of nasopharyngeal carcinoma (NPC), but information on a wide range of macro- and micronutrients is still lacking, particularly for low-incidence countries. METHODS: We conducted a hospital-based case-control study in Italy on 198, histologically confirmed, NPC cases of Caucasian ethnicity of 18-76 years of age. Controls were 594 Caucasian cancer-free patients admitted to general hospitals for acute conditions. Nutrients intake was assessed through a validated food-frequency questionnaire. Adjusted odds ratios (ORs) and the corresponding confidence intervals (CIs) were estimated through logistic regression. RESULTS: Dietary intake of carotenoids were inversely related to NPC risk, notably carotene (OR for highest vs lowest quartile=0.46; 95% CI: 0.26-0.79), α-carotene (OR=0.57; 95% CI: 0.33-0.97), and ß-carotene (OR=0.42; 95% CI: 0.24-0.75). Increased NPC risk was observed for elevate cholesterol intake (OR=1.85; 95% CI: 1.12-3.05). CONCLUSION: Study findings suggest a protective effect of carotenoids against NPC in a low-risk population, adding further support to a possible beneficial role of a diet rich in fruits and vegetables in cancers of the head and neck.


Assuntos
Carotenoides/administração & dosagem , Dieta/estatística & dados numéricos , Neoplasias Nasofaríngeas/epidemiologia , Adolescente , Adulto , Idoso , Carcinoma , Estudos de Casos e Controles , Comportamento Alimentar , Feminino , Humanos , Itália/epidemiologia , Masculino , Micronutrientes/administração & dosagem , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/etiologia , Fatores de Risco , Adulto Jovem
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