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1.
Sci Rep ; 13(1): 1105, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36670214

RESUMO

Single electron tunneling and its transport statistics have been studied for some time using high precision charge detectors. However, this type of detection requires advanced lithography, optimized material systems and low temperatures (mK). A promising alternative, recently demonstrated, is to exploit an optical transition that is turned on or off when a tunnel event occurs. High bandwidths should be achievable with this approach, although this has not been adequately investigated so far. We have studied low temperature resonance fluorescence from a self-assembled quantum dot embedded in a diode structure. We detect single photons from the dot in real time and evaluate the recorded data only after the experiment, using post-processing to obtain the random telegraph signal of the electron transport. This is a significant difference from commonly used charge detectors and allows us to determine the optimal time resolution for analyzing our data. We show how this post-processing affects both the determination of tunneling rates using waiting-time distributions and statistical analysis using full-counting statistics. We also demonstrate, as an example, that we can analyze our data with bandwidths as high as 175 kHz. Using a simple model, we discuss the limiting factors for achieving the optimal bandwidth and propose how a time resolution of more than 1 MHz could be achieved.


Assuntos
Fótons , Pontos Quânticos , Fluorescência
2.
Phys Rev Lett ; 128(8): 087701, 2022 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-35275653

RESUMO

Time-resolved studies of quantum systems are the key to understanding quantum dynamics at its core. The real-time measurement of individual quantum numbers as they switch between certain discrete values, well known as a "random telegraph signal," is expected to yield maximal physical insight. However, the signal suffers from both systematic errors, such as a limited time resolution and noise from the measurement apparatus, as well as statistical errors due to a limited amount of data. Here we demonstrate that an evaluation scheme based on factorial cumulants can reduce the influence of such errors by orders of magnitude. The error resilience is supported by a general theory for the detection errors as well as experimental data of single-electron tunneling through a self-assembled quantum dot. Thus, factorial cumulants push the limits in the analysis of random telegraph data, which represent a wide class of experiments in physics, chemistry, engineering, and life sciences.

3.
Support Care Cancer ; 28(10): 4589-4612, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32533435

RESUMO

BACKGROUND: Digital health provides solutions that capture patient-reported outcomes (PROs) and allows symptom monitoring and patient management. Digital therapeutics is the provision to patients of evidence-based therapeutic interventions through software applications aimed at prevention, monitoring, management, and treatment of symptoms and diseases or for treatment optimization. The digital health solutions collecting PROs address many unmet needs, including access to care and reassurance, increase in adherence and treatment efficacy, and decrease in hospitalizations. With current developments in oncology including increased availability of oral drugs and reduced availability of healthcare professionals, these solutions offer an innovative approach to optimize healthcare resource utilization. DESIGN: This scoping review clarifies the role and impact of the digital health solutions in oncology supportive care, with a view of the current segmentation according to their technical features (connection to sensors, PRO collection, remote monitoring, self-management in real time…), and identifies evidence from clinical studies published about their benefits and limitations and drivers and barriers to adoption. A qualitative summary is presented. RESULTS: Sixty-six studies were identified and included in the qualitative synthesis. Studies supported the use of 38 digital health solutions collecting ePROs and allowing remote monitoring, with benefits to patients regarding symptom reporting and management, reduction in symptom distress, decrease in unplanned hospitalizations and related costs and improved quality of life and survival. Among those 38 solutions 21 provided patient self-management with impactful symptom support, improvement of QoL, usefulness and reassurance. Principal challenges are in developing and implementing digital solutions to suit most patients, while ensuring patient compliance and adaptability for use in different healthcare systems and living environments. CONCLUSIONS: There is growing evidence that digital health collecting ePROs provide benefits to patients related to clinical and health economic endpoints. These digital solutions can be integrated into routine supportive care in oncology practice to provide improved patient-centered care.


Assuntos
Oncologia/métodos , Qualidade de Vida/psicologia , Telemedicina/métodos , Humanos
4.
Phys Rev Lett ; 122(24): 247403, 2019 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-31322370

RESUMO

The maximum information of a dynamic quantum system is given by real-time detection of every quantum event, where the ultimate challenge is a stable, sensitive detector with high bandwidth. All physical information can then be drawn from a statistical analysis of the time traces. We demonstrate here an optical detection scheme based on the time-resolved resonance fluorescence on a single quantum dot. Single-electron resolution with high signal-to-noise ratio (4σ confidence) and high bandwidth of 10 kHz make it possible to record the individual quantum events of the transport dynamics. Full counting statistics with factorial cumulants gives access to the nonequilibrium dynamics of spin relaxation of a singly charged dot (γ_{↑↓}=3 ms^{-1}), even in an equilibrium transport measurement.

5.
Med Oral Patol Oral Cir Bucal ; 23(2): e168-e179, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29476678

RESUMO

BACKGROUND: Oral manifestations are common in neurofibromatosis 1 (NF1), and include jaws and teeth alterations. Our aim was to investigate the craniomaxillofacial morphology of Brazilian children, adolescents and adults with NF1 using cone beam computed tomography. MATERIAL AND METHODS: This study was conducted with 36 Brazilian individuals with NF1 with ages ranging from 4 to 75. The participants were submitted to anamnesis, extra and intraoral exam and cephalometric analysis using cone beam computed tomography. Height of the NF1 individuals was compared to the length of jaws and skull base. The results of the cephalometric measurements of the NF1 group were compared with a control group paired by age, gender and skin color. RESULTS: Individuals with NF1 had lower maxillary length (p<0.0001), lower mandibular length (p<0.0001), lower skull base length (p<0.0001). In children and adolescents, the mandible was more posteriorly positioned (p=0.01), when compared with the control group. There was no association between jaws and skull base length with the height of the individuals with NF1. CONCLUSIONS: Brazilian children, adolescents and adults with NF1 have short mandible, maxilla and skull base. Moreover, children and adolescents present mandibular retrusion.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Arcada Osseodentária/diagnóstico por imagem , Arcada Osseodentária/patologia , Neurofibromatose 1/complicações , Base do Crânio/diagnóstico por imagem , Base do Crânio/patologia , Adolescente , Adulto , Idoso , Brasil , Estudos de Casos e Controles , Cefalometria , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Adulto Jovem
6.
Gynecol Oncol ; 148(2): 275-280, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29195926

RESUMO

OBJECTIVE: To identify clinicopathologic factors associated with 10-year overall survival in epithelial ovarian cancer (EOC) and primary peritoneal cancer (PPC), and to develop a predictive model identifying long-term survivors. METHODS: Demographic, surgical, and clinicopathologic data were abstracted from GOG 182 records. The association between clinical variables and long-term survival (LTS) (>10years) was assessed using multivariable regression analysis. Bootstrap methods were used to develop predictive models from known prognostic clinical factors and predictive accuracy was quantified using optimism-adjusted area under the receiver operating characteristic curve (AUC). RESULTS: The analysis dataset included 3010 evaluable patients, of whom 195 survived greater than ten years. These patients were more likely to have better performance status, endometrioid histology, stage III (rather than stage IV) disease, absence of ascites, less extensive preoperative disease distribution, microscopic disease residual following cyoreduction (R0), and decreased complexity of surgery (p<0.01). Multivariable regression analysis revealed that lower CA-125 levels, absence of ascites, stage, and R0 were significant independent predictors of LTS. A predictive model created using these variables had an AUC=0.729, which outperformed any of the individual predictors. CONCLUSIONS: The absence of ascites, a low CA-125, stage, and R0 at the time of cytoreduction are factors associated with LTS when controlling for other confounders. An extensively annotated clinicopathologic prediction model for LTS fell short of clinical utility suggesting that prognostic molecular profiles are needed to better predict which patients are likely to be long-term survivors.


Assuntos
Neoplasias Epiteliais e Glandulares/mortalidade , Neoplasias Ovarianas/mortalidade , Neoplasias Peritoneais/mortalidade , Idoso , Ascite/mortalidade , Ascite/patologia , Antígeno Ca-125/metabolismo , Carcinoma Epitelial do Ovário , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasia Residual , Neoplasias Epiteliais e Glandulares/patologia , Neoplasias Ovarianas/patologia , Neoplasias Peritoneais/patologia , Curva ROC , Estados Unidos/epidemiologia
7.
Gynecol Oncol ; 145(3): 453-461, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28236454

RESUMO

OBJECTIVE: Natural killer (NK) cells represent a powerful immunotherapeutic target as they lyse tumors directly, do not require differentiation, and can elicit potent inflammatory responses. The objective of these studies was to use an IL-15 super-agonist complex, ALT-803 (Altor BioScience Corporation), to enhance the function of both normal and ovarian cancer patient derived NK cells by increasing cytotoxicity and cytokine production. METHODS: NK cell function from normal donor peripheral blood mononuclear cells (PBMCs) and ovarian cancer patient ascites was assessed using flow cytometry and chromium release assays ±ALT-803 stimulation. To evaluate the ability of ALT-803 to enhance NK cell function in vivo against ovarian cancer, we used a MA148-luc ovarian cancer NOD scid gamma (NSG) xenogeneic mouse model with transferred human NK cells. RESULTS: ALT-803 potently enhanced functionality of NK cells against all ovarian cancer cell lines with significant increases seen in CD107a, IFNγ and TNFα expression depending on target cell line. Function was also rescued in NK cells derived from ovarian cancer patient ascites. Finally, only animals treated with intraperitoneal ALT-803 displayed an NK dependent significant decrease in tumor. CONCLUSIONS: ALT-803 enhances NK cell cytotoxicity against ovarian cancer in vitro and in vivo and is able to rescue functionality of NK cells derived from ovarian cancer patient ascites. These findings suggest that ALT-803 has the potential to enhance NK cell-based immunotherapeutic approaches for the treatment of ovarian cancer.


Assuntos
Interleucina-15/agonistas , Células Matadoras Naturais/efeitos dos fármacos , Células Matadoras Naturais/imunologia , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/imunologia , Proteínas/farmacologia , Animais , Ascite/imunologia , Ascite/patologia , Feminino , Humanos , Células K562 , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/imunologia , Ativação Linfocitária/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Proteínas Recombinantes de Fusão , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Phys Rev Lett ; 117(1): 017401, 2016 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-27419589

RESUMO

Time-resolved resonance fluorescence (RF) is used to analyze electron tunneling between a single self-assembled quantum dot (QD) and an electron reservoir. In equilibrium, the RF intensity reflects the average electron occupation of the QD and exhibits a gate voltage dependence that is given by the Fermi distribution in the reservoir. In the time-resolved signal, however, we find that the relaxation rate for electron tunneling is, surprisingly, independent of the occupation in the charge reservoir-in contrast to results from all-electrical transport measurements. Using a master equation approach, which includes both the electron tunneling and the optical excitation or recombination, we are able to explain the experimental data by optical blocking, which also reduces the electron tunneling rate when the QD is occupied by an exciton.

9.
Osteoporos Int ; 27(1): 75-80, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26174879

RESUMO

UNLABELLED: Two comorbidity indices were adapted for use in the FREEDOM trial and significantly correlated with the number of medications and impaired health status at baseline. The indices have applications for the analysis of clinical trial data and would allow for the appropriate adjustment of comorbidities when evaluating clinical trial outcomes. INTRODUCTION: The purpose of this study is to adapt two published comorbidity indices for use with the FREEDOM clinical trial evaluating postmenopausal women with osteoporosis. METHODS: FREEDOM enrolled women aged 60-90 years with a bone mineral density T-score <-2.5 at the lumbar spine or total hip and ≥-4.0 at both sites. Comorbidity indices were calculated using methods described by Sangha (Arthritis Rheum 49:156-163, 2003) and Wolfe (J Rheumatol 37:305-315, 2010) following modification. The adapted Sangha index included 12 conditions with a summary score of 0-12; the adapted Wolfe index included 7 conditions with a weighted summary score of 0-8. Higher scores indicated greater comorbidity. A panel of clinicians independently reviewed subjects' medical histories using a systematic process based on Medical Dictionary for Regulatory Activities (MedDRA) preferred terms to map specified comorbid conditions. Spearman correlations between the adapted indices and baseline subject characteristics expected to be associated with comorbidities were examined. RESULTS: Of the 7808 subjects in this study, 74 % had ≥1 comorbidities based on the adapted Sangha or Wolfe comorbidity indices. The mean (SD) adapted Sangha and Wolfe comorbidity indices were 1.4 (1.2) and 1.4 (1.3), respectively. Both indices correlated positively with age, body mass index, and the number of medications (r = 0.54 to 0.55) at baseline and inversely correlated with health-related quality of life (r = -0.22 to -0.30) (all P < 0.0001). Further, when either the adapted Sangha or Wolfe index was included as a covariate for assessing mortality over 36 months in the FREEDOM population, the hazard ratio of the comorbidity index indicated that the mortality risk increased by 27 or 28 %, respectively, for each unit increase in the adapted index (both P < 0.0001). CONCLUSIONS: Our work suggests these comorbidity indices may be adapted for use with clinical trial data, thereby allowing for the appropriate adjustment and reporting of covariates in the evaluation of clinical trial outcomes in an osteoporotic population.


Assuntos
Indicadores Básicos de Saúde , Osteoporose Pós-Menopausa/epidemiologia , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Densidade Óssea/fisiologia , Conservadores da Densidade Óssea/uso terapêutico , Comorbidade , Denosumab/uso terapêutico , Método Duplo-Cego , Feminino , Humanos , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/tratamento farmacológico , Osteoporose Pós-Menopausa/fisiopatologia , Estudos Retrospectivos , Resultado do Tratamento , Estados Unidos/epidemiologia
10.
Braz J Med Biol Res ; 48(10): 939-44, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26445338

RESUMO

Low-level lasers are used at low power densities and doses according to clinical protocols supplied with laser devices or based on professional practice. Although use of these lasers is increasing in many countries, the molecular mechanisms involved in effects of low-level lasers, mainly on DNA, are controversial. In this study, we evaluated the effects of low-level red lasers on survival, filamentation, and morphology of Escherichia colicells that were exposed to ultraviolet C (UVC) radiation. Exponential and stationary wild-type and uvrA-deficientE. coli cells were exposed to a low-level red laser and in sequence to UVC radiation. Bacterial survival was evaluated to determine the laser protection factor (ratio between the number of viable cells after exposure to the red laser and UVC and the number of viable cells after exposure to UVC). Bacterial filaments were counted to obtain the percentage of filamentation. Area-perimeter ratios were calculated for evaluation of cellular morphology. Experiments were carried out in duplicate and the results are reported as the means of three independent assays. Pre-exposure to a red laser protected wild-type and uvrA-deficient E. coli cells against the lethal effect of UVC radiation, and increased the percentage of filamentation and the area-perimeter ratio, depending on UVC fluence and physiological conditions in the cells. Therapeutic, low-level red laser radiation can induce DNA lesions at a sub-lethal level. Consequences to cells and tissues should be considered when clinical protocols based on this laser are carried out.


Assuntos
DNA Bacteriano/efeitos da radiação , Escherichia coli/efeitos da radiação , Terapia com Luz de Baixa Intensidade/efeitos adversos , Raios Ultravioleta/efeitos adversos , Dano ao DNA/fisiologia , Escherichia coli/crescimento & desenvolvimento , Escherichia coli/fisiologia , Raios Ultravioleta/classificação
11.
Braz. j. med. biol. res ; 48(10): 939-944, Oct. 2015. tab, ilus
Artigo em Inglês | LILACS | ID: lil-761595

RESUMO

Low-level lasers are used at low power densities and doses according to clinical protocols supplied with laser devices or based on professional practice. Although use of these lasers is increasing in many countries, the molecular mechanisms involved in effects of low-level lasers, mainly on DNA, are controversial. In this study, we evaluated the effects of low-level red lasers on survival, filamentation, and morphology of Escherichia colicells that were exposed to ultraviolet C (UVC) radiation. Exponential and stationary wild-type and uvrA-deficientE. coli cells were exposed to a low-level red laser and in sequence to UVC radiation. Bacterial survival was evaluated to determine the laser protection factor (ratio between the number of viable cells after exposure to the red laser and UVC and the number of viable cells after exposure to UVC). Bacterial filaments were counted to obtain the percentage of filamentation. Area-perimeter ratios were calculated for evaluation of cellular morphology. Experiments were carried out in duplicate and the results are reported as the means of three independent assays. Pre-exposure to a red laser protected wild-type and uvrA-deficient E. coli cells against the lethal effect of UVC radiation, and increased the percentage of filamentation and the area-perimeter ratio, depending on UVC fluence and physiological conditions in the cells. Therapeutic, low-level red laser radiation can induce DNA lesions at a sub-lethal level. Consequences to cells and tissues should be considered when clinical protocols based on this laser are carried out.


Assuntos
DNA Bacteriano/efeitos da radiação , Escherichia coli/efeitos da radiação , Terapia com Luz de Baixa Intensidade/efeitos adversos , Raios Ultravioleta/efeitos adversos , Dano ao DNA/fisiologia , Escherichia coli/crescimento & desenvolvimento , Escherichia coli/fisiologia , Raios Ultravioleta/classificação
12.
J Clin Pediatr Dent ; 39(2): 168-71, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25823487

RESUMO

Neurofibromatosis type 1 (NF1) is a common autosomal genetic disorder with a prevalence of 1 in 3,000 births. NF1 is a complex syndrome characterized by many abnormalities and may affect all organ systems. Oral manifestations of NF1 occur frequently, but reports including NF1 children with facial plexiform neurofibromas and oral alterations are scant. Facial plexiform neurofibroma may cause asymmetry, disfigurement and usually arises from the trigeminal nerve. The aim of this paper is to to report three pediatric NF1 cases with facial plexiform neurofibroma presenting with oral manifestations, which were evaluated clinically and radiographically, and also to briefly review the literature. Patients presented with changes in the oral soft tissues, jaws, and teeth ipsilateral to the tumor.


Assuntos
Deformidades Dentofaciais/diagnóstico , Neoplasias Faciais/diagnóstico , Neurofibroma Plexiforme/diagnóstico , Neurofibromatose 1/diagnóstico , Criança , Feminino , Neoplasias Gengivais/diagnóstico , Crescimento Excessivo da Gengiva/diagnóstico , Humanos , Macroglossia/diagnóstico , Masculino , Má Oclusão/diagnóstico , Mandíbula/anormalidades , Côndilo Mandibular/anormalidades , Neoplasias da Língua/diagnóstico
13.
Biomed Tech (Berl) ; 59 Suppl 1: s471-89, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25385892
14.
Osteoporos Int ; 24(1): 227-35, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22776860

RESUMO

UNLABELLED: In a phase 2 study, continued denosumab treatment for up to 8 years was associated with continued gains in bone mineral density and persistent reductions in bone turnover markers. Denosumab treatment was well tolerated throughout the 8-year study. INTRODUCTION: The purpose of this study is to present the effects of 8 years of continued denosumab treatment on bone mineral density (BMD) and bone turnover markers (BTM) from a phase 2 study. METHODS: In the 4-year parent study, postmenopausal women with low BMD were randomized to receive placebo, alendronate, or denosumab. After 2 years, subjects were reallocated to continue, discontinue, or discontinue and reinitiate denosumab; discontinue alendronate; or maintain placebo for two more years. The parent study was then extended for 4 years where all subjects received denosumab. RESULTS: Of the 262 subjects who completed the parent study, 200 enrolled in the extension, and of these, 138 completed the extension. For the subjects who received 8 years of continued denosumab treatment, BMD at the lumbar spine (N = 88) and total hip (N = 87) increased by 16.5 and 6.8 %, respectively, compared with their parent study baseline, and by 5.7 and 1.8 %, respectively, compared with their extension study baseline. For the 12 subjects in the original placebo group, 4 years of denosumab resulted in BMD gains comparable with those observed during the 4 years of denosumab in the parent study. Reductions in BTM were sustained over the course of continued denosumab treatment. Reductions also were observed when the placebo group transitioned to denosumab. Adverse event profile was consistent with previous reports and an aging cohort. CONCLUSION: Continued denosumab treatment for 8 years was associated with progressive gains in BMD, persistent reductions in BTM, and was well tolerated.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Conservadores da Densidade Óssea/uso terapêutico , Densidade Óssea/efeitos dos fármacos , Remodelação Óssea/efeitos dos fármacos , Osteoporose Pós-Menopausa/tratamento farmacológico , Idoso , Fosfatase Alcalina/sangue , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/efeitos adversos , Anticorpos Monoclonais Humanizados/farmacologia , Biomarcadores/sangue , Conservadores da Densidade Óssea/administração & dosagem , Conservadores da Densidade Óssea/efeitos adversos , Conservadores da Densidade Óssea/farmacologia , Colágeno Tipo I/sangue , Denosumab , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Articulação do Quadril/fisiopatologia , Humanos , Vértebras Lombares/fisiopatologia , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/sangue , Osteoporose Pós-Menopausa/fisiopatologia , Peptídeos/sangue , Resultado do Tratamento
15.
Allergy ; 67(8): 976-97, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22702533

RESUMO

Asthma is the most common chronic lower respiratory disease in childhood throughout the world. Several guidelines and/or consensus documents are available to support medical decisions on pediatric asthma. Although there is no doubt that the use of common systematic approaches for management can considerably improve outcomes, dissemination and implementation of these are still major challenges. Consequently, the International Collaboration in Asthma, Allergy and Immunology (iCAALL), recently formed by the EAACI, AAAAI, ACAAI, and WAO, has decided to propose an International Consensus on (ICON) Pediatric Asthma. The purpose of this document is to highlight the key messages that are common to many of the existing guidelines, while critically reviewing and commenting on any differences, thus providing a concise reference. The principles of pediatric asthma management are generally accepted. Overall, the treatment goal is disease control. To achieve this, patients and their parents should be educated to optimally manage the disease, in collaboration with healthcare professionals. Identification and avoidance of triggers is also of significant importance. Assessment and monitoring should be performed regularly to re-evaluate and fine-tune treatment. Pharmacotherapy is the cornerstone of treatment. The optimal use of medication can, in most cases, help patients control symptoms and reduce the risk for future morbidity. The management of exacerbations is a major consideration, independent of chronic treatment. There is a trend toward considering phenotype-specific treatment choices; however, this goal has not yet been achieved.


Assuntos
Asma/diagnóstico , Asma/terapia , Adolescente , Asma/classificação , Asma/prevenção & controle , Criança , Pré-Escolar , Humanos , Lactente , Recém-Nascido
16.
Nutr Hosp ; 27(1): 65-75, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22566305

RESUMO

Antineoplastic chemotherapy (CT) represents the systemic treatment of malignant tumors. It can be used alone or combined with surgery and / or radiotherapy. The cytotoxic agents used in chemotherapy work on both cancerous cells and noncancerous cells of the body, generally resulting in high toxicity. The biological aggressiveness of chemotherapy particularly affects rapidly replicating cells, such as those of the digestive tract, resulting in adverse effects that impair food intake, leading to compromised nutritional status and which may lead to cachexia. The main toxic effects of chemotherapy in the gastrointestinal tract include nausea, vomiting -these are the most frequent- constipation, diarrhea, xerostomia, mucositis, dysphagia and anorexia. Given the high frequency of such effects, nutritional intervention should be an integral part of cancer treatment, to maintain and/or improve the patient's nutritional status and reduce or minimize the side effects caused by treatment. Accordingly, the goal of this study is to review dietetic conduct in the process of caring for patients undergoing cancer chemotherapy.


Assuntos
Antineoplásicos/efeitos adversos , Gastroenteropatias/induzido quimicamente , Gastroenteropatias/dietoterapia , Anorexia/induzido quimicamente , Anorexia/dietoterapia , Constipação Intestinal/induzido quimicamente , Constipação Intestinal/dietoterapia , Transtornos de Deglutição/induzido quimicamente , Transtornos de Deglutição/dietoterapia , Diarreia/induzido quimicamente , Diarreia/dietoterapia , Humanos , Náusea/induzido quimicamente , Náusea/dietoterapia , Neoplasias/complicações , Neoplasias/tratamento farmacológico , Estado Nutricional , Estomatite/induzido quimicamente , Estomatite/dietoterapia , Vômito/induzido quimicamente , Vômito/dietoterapia , Xerostomia/induzido quimicamente , Xerostomia/dietoterapia
17.
Nutr. hosp ; 27(1): 65-75, ene.-feb. 2012. tab
Artigo em Inglês | IBECS | ID: ibc-104855

RESUMO

Antineoplastic chemotherapy (CT) represents the systemic treatment of malignant tumors. It can be used alone or combined with surgery and / or radiotherapy. The cytotoxic agents used in chemotherapy work on both cancerous cells and noncancerous cells of the body, generally resulting in high toxicity. The biological aggressiveness of chemotherapy particularly affects rapidly replicating cells, such as those of the digestive tract, resulting in adverse effects that impair food intake, leading to compromised nutritional status and which may lead to cachexia. The main toxic effects of chemotherapy in the gastrointestinal tract include nausea, vomiting -these are the most frequent- constipation, diarrhea, xerostomia, mucositis, dysphagia and anorexia. Given the high frequency of such effects, nutritional intervention should be an integral part of cancer treatment, to maintain nd/or improve the patient’s nutritional status and reduce or minimize the side effects caused by treatment. Accordingly, the goal of this study is to review dietetic conduct in the process of caring for patients undergoing cancer chemotherapy (AU)


La quimioterapia (QT) representa el tratamiento antineoplásico sistémico de los tumores malignos. Puede ser utilizada solo o combinada con la cirugía y / o radioterapia. Los agentes quimioterápicos actúan en las células cancerosas y las células normales del cuerpo, siendo por lo general muy tóxicos. La agresividad de la quimioterapia afecta especialmente rápida replicación celular en el tracto digestivo, dando lugar a efectos adversos que impiden la ingesta de alimentos, dando lugar al estado nutricional comprometido y puede conducir a la caquexia. Los principales efectos tóxicos de la quimioterapia, el tracto gastrointestinal, como náuseas, vómitos -estos son los más frecuentes- estreñimiento, diarrea, sequedad deboca, mucositis disfagia y anorexia. Dada la alta frecuencia de tales efectos, la intervención nutricional debe ser parte integral del tratamiento del cáncer, para mantener y/o mejorar el estado nutricional del paciente y reducir ominimizar los efectos secundarios del tratamiento. En efecto, la revisión de la dietética conducta en el proceso de cuidar de los pacientes en quimioterapia contra el cánceres el objetivo de este trabajo (AU)


Assuntos
Humanos , Antineoplásicos/toxicidade , /dietoterapia , Gastroenteropatias/dietoterapia , Neoplasias/complicações , Gastroenteropatias/induzido quimicamente , Eméticos/efeitos adversos , Vômito/induzido quimicamente , Constipação Intestinal/induzido quimicamente , Transtornos de Deglutição/induzido quimicamente
18.
Nat Commun ; 2: 209, 2011 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-21343927

RESUMO

Self-assembled quantum dots (QDs) are prominent candidates for solid-state quantum information processing. For these systems, great progress has been made in addressing spin states by optical means. In this study, we introduce an all-electrical measurement technique to prepare and detect non-equilibrium many-particle spin states in an ensemble of self-assembled QDs at liquid helium temperature. The excitation spectra of the one- (QD hydrogen), two- (QD helium) and three- (QD lithium) electron configuration are shown and compared with calculations using the exact diagonalization method. An exchange splitting of 10 meV between the excited triplet and singlet spin states is observed in the QD helium spectrum. These experiments are a starting point for an all-electrical control of electron spin states in self-assembled QDs above liquid helium temperature.


Assuntos
Processamento Eletrônico de Dados/métodos , Elétrons , Pontos Quânticos , Análise Espectral/métodos , Hélio , Microscopia de Força Atômica , Temperatura
19.
Nanotechnology ; 22(8): 085702, 2011 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-21242617

RESUMO

We present GaAs electroluminescent nanowire structures fabricated by metal organic vapor phase epitaxy. Electroluminescent structures were realized in both axial pn-junctions in single GaAs nanowires and free-standing nanowire arrays with a pn-junction formed between nanowires and substrate, respectively. The electroluminescence emission peak from single nanowire pn-junctions at 10 K was registered at an energy of around 1.32 eV and shifted to 1.4 eV with an increasing current. The line is attributed to the recombination in the compensated region present in the nanowire due to the memory effect of the vapor-liquid-solid growth mechanism. Arrayed nanowire electroluminescent structures with a pn-junction formed between nanowires and substrate demonstrated at 5 K a strong electroluminescence peak at 1.488 eV and two shoulder peaks at 1.455 and 1.519 eV. The main emission line was attributed to the recombination in the p-doped GaAs. The other two lines correspond to the tunneling-assisted photon emission and band-edge recombination in the abrupt junction, respectively. Electroluminescence spectra are compared with the micro-photoluminescence spectra taken along the single p-, n- and single nanowire pn-junctions to find the origin of the electroluminescence peaks, the distribution of doping species and the sharpness of the junctions.

20.
Nanotechnology ; 22(4): 045301, 2011 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-21157014

RESUMO

We demonstrate the gas-assisted focused-electron-beam (FEB)-induced etching of GaAs with a resolution of 30 nm at room temperature. We use a scanning electron microscope (SEM) in a dual beam focused ion beam together with xenon difluoride (XeF(2)) that can be injected by a needle directly onto the sample surface. We show that the FEB-induced etching with XeF(2) as a precursor gas results in isotropic and smooth etching of GaAs, while the etch rate depends strongly on the beam current and the electron energy. The natural oxide of GaAs at the sample surface inhibits the etching process; hence, oxide removal in combination with chemical surface passivation is necessary as a strategy to enable this high-resolution etching alternative for GaAs.

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