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1.
Ann Oncol ; 35(2): 229-239, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37992872

RESUMO

BACKGROUND: Increasingly, circulating tumor DNA (ctDNA) is proposed as a tool for minimal residual disease (MRD) assessment. Digital PCR (dPCR) offers low analysis costs and turnaround times of less than a day, making it ripe for clinical implementation. Here, we used tumor-informed dPCR for ctDNA detection in a large colorectal cancer (CRC) cohort to evaluate the potential for post-operative risk assessment and serial monitoring, and how the metastatic site may impact ctDNA detection. Additionally, we assessed how altering the ctDNA-calling algorithm could customize performance for different clinical settings. PATIENTS AND METHODS: Stage II-III CRC patients (N = 851) treated with a curative intent were recruited. Based on whole-exome sequencing on matched tumor and germline DNA, a mutational target was selected for dPCR analysis. Plasma samples (8 ml) were collected within 60 days after operation and-for a patient subset (n = 246)-every 3-4 months for up to 36 months. Single-target dPCR was used for ctDNA detection. RESULTS: Both post-operative and serial ctDNA detection were prognostic of recurrence [hazard ratio (HR) = 11.3, 95% confidence interval (CI) 7.8-16.4, P < 0.001; HR = 30.7, 95% CI 20.2-46.7, P < 0.001], with a cumulative ctDNA detection rate of 87% at the end of sample collection in recurrence patients. The ctDNA growth rate was prognostic of survival (HR = 2.6, 95% CI 1.5-4.4, P = 0.001). In recurrence patients, post-operative ctDNA detection was challenging for lung metastases (4/21 detected) and peritoneal metastases (2/10 detected). By modifying the cut-off for calling a sample ctDNA positive, we were able to adjust the sensitivity and specificity of our test for different clinical contexts. CONCLUSIONS: The presented results from 851 stage II-III CRC patients demonstrate that our personalized dPCR approach effectively detects MRD after operation and shows promise for serial ctDNA detection for recurrence surveillance. The ability to adjust sensitivity and specificity shows exciting potential to customize the ctDNA caller for specific clinical settings.


Assuntos
DNA Tumoral Circulante , Neoplasias Colorretais , Humanos , DNA Tumoral Circulante/genética , DNA de Neoplasias/genética , Algoritmos , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/genética , Dinamarca , Biomarcadores Tumorais/genética , Recidiva Local de Neoplasia
2.
Respir Res ; 22(1): 156, 2021 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-34020646

RESUMO

BACKGROUND: Although cardiac autonomic modulation has been studied in several respiratory diseases, the evidence is limited on lung transplantation, particularly on its acute and chronic effects. Thus, we aimed to evaluate cardiac autonomic modulation before and after bilateral lung transplantation (BLT) through a prospective study on patients enrolled while awaiting transplant. METHODS: Twenty-two patients on the waiting list for lung transplantation (11 women, age 33 [24-51] years) were enrolled in a prospective study at Ospedale Maggiore Policlinico Hospital in Milan, Italy. To evaluate cardiac autonomic modulation, ten minutes ECG and respiration were recorded at different time points before (T0) and 15 days (T1) and 6 months (T2) after bilateral lung transplantation. As to the analysis of cardiac autonomic modulation, heart rate variability (HRV) was assessed using spectral and symbolic analysis. Entropy-derived measures were used to evaluate complexity of cardiac autonomic modulation. Comparisons of autonomic indices at different time points were performed. RESULTS: BLT reduced HRV total power, HRV complexity and vagal modulation, while it increased sympathetic modulation in the acute phase (T1) compared to baseline (T0). The HRV alterations remained stable after 6 months (T2). CONCLUSION: BLT reduced global variability and complexity of cardiac autonomic modulation in acute phases, and these alterations remain stable after 6 months from surgery. After BLT, a sympathetic predominance and a vagal withdrawal could be a characteristic autonomic pattern in this population.


Assuntos
Sistema Nervoso Autônomo/fisiopatologia , Frequência Cardíaca , Coração/inervação , Pneumopatias/cirurgia , Transplante de Pulmão , Pulmão/cirurgia , Respiração , Adulto , Eletrocardiografia , Feminino , Humanos , Pulmão/fisiopatologia , Pneumopatias/diagnóstico , Pneumopatias/fisiopatologia , Transplante de Pulmão/efeitos adversos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
3.
Eur Rev Med Pharmacol Sci ; 25(4): 2099-2108, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33660823

RESUMO

OBJECTIVE: Ustekinumab (UST) is an anti-IL12/23 antibody for the treatment of Crohn's Disease (CD). The aim of this study was to compare the efficacy and safety of UST in a large population-based cohort of CD patients who failed previous treatment with other biologics. PATIENTS AND METHODS: 194 CD patients (108 males and 86 females, mean age 48 years (range 38-58 years) were retrospectively reviewed. 147 patients were already treated with anti-TNFα (75.8%), and 47 (24.2%) patients were already treated with anti-TNFα and vedolizumab. Concomitant treatment with steroids was present in 177 (91.2%) patients. RESULTS: At week 12, clinical remission was achieved in 146 (75.2%) patients. After a mean follow-up of 6 months, clinical remission was maintained in 135 (69.6%) patients; at that time, mucosal healing was assessed in 62 (31.9%) patients, and it was achieved in 33 (53.2) patients. Three (1.5%) patients were submitted to surgery. Steroid-free remission was achieved in 115 (59.3%) patients. Both serum C-Reactive Protein and Fecal Calprotectin (FC) levels were significantly reduced with respect to baseline levels during follow-up. A logistic regression, UST therapy as third-line therapy (after both anti-TNFα and vedolizumab), FC >200 µg/g, and HBI ≥8 were significantly associated with lack of remission. Adverse events occurred in 5 (2.6%) patients, and four of them required suspension of treatment. CONCLUSIONS: UST seemed to be really effective and safe in CD patients unresponsive to other biologic treatments, especially when used as second-line treatment.


Assuntos
Doença de Crohn/tratamento farmacológico , Ustekinumab/uso terapêutico , Adulto , Estudos de Coortes , Feminino , Humanos , Itália , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Ustekinumab/administração & dosagem , Ustekinumab/efeitos adversos
4.
J Math Biol ; 79(3): 1149-1167, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31203388

RESUMO

In reconstructing the common evolutionary history of hosts and parasites, the current method of choice is the phylogenetic tree reconciliation. In this model, we are given a host tree H, a parasite tree P, and a function [Formula: see text] mapping the leaves of P to the leaves of H and the goal is to find, under some biologically motivated constraints, a reconciliation, that is a function from the vertices of P to the vertices of H that respects [Formula: see text] and allows the identification of biological events such as co-speciation, duplication and host switch. The maximum co-divergence problem consists in finding the maximum number of co-speciations in a reconciliation. This problem is NP-hard for arbitrary phylogenetic trees and no approximation algorithm is known. In this paper we consider the influence of tree topology on the maximum co-divergence problem. In particular we focus on a particular tree structure, namely caterpillar, and show that-in this case-the heuristics that are mostly used in the literature provide solutions that can be arbitrarily far from the optimal value. Then, we prove that finding the max co-divergence is equivalent to compute the maximum length of a subsequence with certain properties of a given permutation. This equivalence leads to two consequences: (1) it shows that we can compute efficiently in polynomial time the optimal time-feasible reconciliation and (2) it can be used to understand how much the tree topology influences the value of the maximum number of co-speciations.


Assuntos
Algoritmos , Biologia Computacional/métodos , Evolução Molecular , Modelos Genéticos , Filogenia , Animais , Humanos
5.
Peptides ; 102: 38-46, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29486214

RESUMO

Solid-Phase Peptide Synthesis (SPPS) is a rapid and efficient methodology for the chemical synthesis of peptides and small proteins. However, the assembly of peptide sequences classified as "difficult" poses severe synthetic problems in SPPS for the occurrence of extensive aggregation of growing peptide chains which often leads to synthesis failure. In this framework, we have investigated the impact of different synthetic procedures on the yield and final purity of three well-known "difficult peptides" prepared using oxyma as additive for the coupling steps. In particular, we have comparatively investigated the use of piperidine and morpholine/DBU as deprotection reagents, the addition of DIPEA, collidine and N-methylmorpholine as bases to the coupling reagent. Moreover, the effect of different agitation modalities during the acylation reactions has been investigated. Data obtained represent a step forward in optimizing strategies for the synthesis of "difficult peptides".


Assuntos
Peptídeos/síntese química , Pregnadienos/química , Agregados Proteicos , Técnicas de Síntese em Fase Sólida , Acilação , Sequência de Aminoácidos , Etilaminas/química , Morfolinas/química , Peptídeos/química , Peptídeos/genética , Piperidinas/química , Piridinas/química
6.
Rev Med Interne ; 36(1): 7-9, 2015 Jan.
Artigo em Francês | MEDLINE | ID: mdl-24373728

RESUMO

INTRODUCTION: Switching from fluindione, an indanedione vitamin K antagonist derivative, to warfarin, a coumarin one, or vice versa, requires to know the relationships between dosages of these two molecules. METHODS: We conducted a prospective study in 288 consecutive patients aged 70 years and over, converted from fluindione to warfarin. Patients who were retained for the analysis were those for whom maintenance dosages were obtained for both vitamin K antagonists. RESULTS: Eighty-two patients, mean aged 83 ± 6 years, were analysed. The average daily maintenance dosages were 13.8 ± 6.7 mg (range 5-35) and 3.7 ± 1.7 mg (range 1-8) for fluindione and warfarin, respectively. Using a linear regression model, we built a transition algorithm for the maintenance dosages of warfarin and fluindione. CONCLUSION: This is the first study to propose a conversion algorithm to help prescribers to estimate the maintenance dosage when it is necessary for a patient to switch from fluindione to warfarin or conversely.


Assuntos
Anticoagulantes/administração & dosagem , Cálculos da Dosagem de Medicamento , Nomogramas , Fenindiona/análogos & derivados , Trombose/prevenção & controle , Varfarina/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/metabolismo , Algoritmos , Anticoagulantes/farmacocinética , Relação Dose-Resposta a Droga , Substituição de Medicamentos , Feminino , Humanos , Masculino , Fenindiona/administração & dosagem , Fenindiona/farmacocinética , Equivalência Terapêutica , Trombose/metabolismo , Varfarina/farmacocinética
7.
J Pharm Belg ; (3): 30-7, 2014 Sep.
Artigo em Francês | MEDLINE | ID: mdl-25226761

RESUMO

INTRODUCTION: Elderly people with vitamin K antagonists (VKA) have a higher risk of potentially serious hemorrhagic complications. An education program for patients (EPP) aged > or = 75 years with VKA was set up in 2008 in a French geriatric hospital. It includes individual and group sessions conducted by a nurse and a geriatrician. OBJECTIVES: The aim of this study was to assess this EPP after 5 years. Strengths, weaknesses and difficulties of implementation were highlighted, and some improvements were proposed. METHODS: This study is an external audit conducted by a pharmacist trained in EPP. Files of consecutive patients included in the program between may 2008 and March 2013 were reviewed allowing the data collection of patients characteristics and results of the different sessions. The educational objectives were assessed by the rate of correct responses to the questionnaires during the program. The results are presented taking into account the changes made during the 5 years of the program. RESULTS: One hundred forty-three patients, mean age 83.3 +/- 6.5 years, were included in the EPP. 51 sessions were conducted (2.8 patients/session on average). 58% of selected patients were hospitalized. The mean time between the start of anticoagulant treatment and the incLusion in the program was 48.9 +/- 71 months. For 95 patients (66.4%) the medication management at home required a caregiver who was present for sessions in 82 cases (57.3%). The questionnaires form and the organisation of the sessions were gradually improved between 2008 and the end of 2010. Thus, the impact of the EPP has been estimated from November 2010 to March 2013. The correct responses rates before and after the sessions were respectively: 47.8% vs 91.3% for knowledge of INR target values, 25.4% vs 91.3% for knowledge of hemorrhagic signs, 14.9% vs 87.0% for knowledge of the situations or the medications that may disturb the INR equilibrium. Furthermore, the mean number of correct responses, for the 23 patients participating in the entire program, is statistically different between the educational diagnostic and immediate evaluation (3.7/7 vs 5.4/7 p = 0.023) and no significant difference is observed between immediate and distant evaluation (5.4/7 vs 5.8/7 p = 0.720). CONCLUSION: An improvement of patient knowledge was observed with regard to the main educational objectives. Some improvements are proposed: to disseminate information to general practitioners, to add the follow up of INR values to assess an impact on anticoagulant treatment stability. Furthermore, this program is now adapted to the new oral anticoagulants. It is the role of hospital or community pharmacists to initiate and/or assess this type of EPP.


Assuntos
Anticoagulantes/uso terapêutico , Educação de Pacientes como Assunto , Vitamina K/antagonistas & inibidores , Idoso , Idoso de 80 Anos ou mais , Anticoagulantes/efeitos adversos , Feminino , Humanos , Masculino , Inquéritos e Questionários
8.
Med Lav ; 103(3): 220-9, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22838300

RESUMO

INTRODUCTION: The development in an extremely short time of an efficacious and safe vaccine against the pandemi A/H1N1 virus was a challenge that involved the entire scientific community. AIMS: To assess the immunological and clinical efficacy of the new H1N1v monovalent influenza vaccine (Focetria Novartis Vaccines, Siena, Italy) in a group of health care workers (HCWs). METHODS: A total of 148 volunteer HCWs were enrolled between Mid-Novembre 2009 and December 2009. After measuring antibody titers, a single intramuscular dose of 7.5 microg of Focetria monovalent vaccine against A/H1N1/2009 influenza virus with MF59C.1 adjuvant was administered. RESULTS: Antibody titers (median value) before and after a single dose of vaccine, measured by means of standard beam-agglutination inhibition test (HAI), increased from 32 to 256 (p < 0.001). After vaccination, 79.7% of the subjects showed antibody seroconversion, and in 97.3% seroprotection was achieved. The ratio between the geometric means of antibody titers (GMTR) was 6.69. For the 3 subjects who reported symptoms of ILI (Influenza-like illness), a regular nasal-pharyngeal swab sample was taken to identify the virus type by RT-PCR, the laboratory results of tests performed on these samples were negative for pandemic A/H1N1/2009 virus. During the entire follow-up period of 6 months no severe adverse events occurred. CONCLUSIONS: The vaccine against pandemic A/H1N1/2009 virus provided protection against the virus and not only contributed to a significant immunization (according to EMEA criteria), but kept all 148 subjects under study free from A/H1N1/2009 influenza illness.


Assuntos
Anticorpos Antivirais/sangue , Pessoal de Saúde , Imunização , Vírus da Influenza A Subtipo H1N1/imunologia , Vacinas contra Influenza , Influenza Humana/prevenção & controle , Adulto , Idoso , Feminino , Humanos , Vacinas contra Influenza/efeitos adversos , Masculino , Pessoa de Meia-Idade , Segurança , Adulto Jovem
9.
Neuroscience ; 212: 59-76, 2012 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-22516013

RESUMO

Vision (V) and touch (T) help stabilize our standing body, but little is known on the time-interval necessary for the brain to process the sensory inflow (or its removal) and exploit the new information (or counteract its removal). We have estimated the latency of onset and the time-course of the changes in postural control mode following addition or withdrawal of sensory information and the effect of anticipation thereof. Ten subjects stood in tandem position. They wore LCD goggles that allowed or removed vision, or lightly touched (eyes-closed) with the index finger (haptic stimulation) a pad that could be suddenly lowered (passive task). In different sessions, sensory shifts were deliberately produced by opening (or closing) the eyes or touching the pad (or lifting the finger) (active task). We recorded eyelid movement and finger force (<1N), sway of center of foot pressure (CoP), electromyogram (EMG) of soleus, tibialis and peroneus muscle, bilaterally, and of extensor indicis. The latency of the CoP and EMG changes following the shifts were statistically estimated on the averaged traces of 50 repetitions per condition. Muscle activity and sway adaptively decreased in amplitude on adding stabilizing visual or haptic information. The time-interval from the sensory shift to decrease in EMG and sway was ∼0.5-2 s under both conditions. It was shorter for tibialis than peroneus or soleus and shorter for visual than haptic shift. CoP followed the tibialis by ∼0.2 s. Slightly shorter intervals were observed following active sensory shifts. Latencies of EMG and postural changes were the shortest on removal of both haptic and visual information. Subsequently, the time taken to reach the steady-state was ∼1-3 s under both active and passive tasks. A startle response at ∼100 ms could precede EMG changes. Reaction-time contractions in response to sensory shifts appeared at ∼200 ms, earlier than the adaptive changes. Changes in postural behavior require a finite amount of time from visual or haptic shift, much longer than reflexes or rapid voluntary responses, suggesting a time-consuming central integration process. This process is longer on addition than removal of haptic information, indicating a heavier computational load. These findings should be taken into account when considering problems of sensorimotor integration in elderly subjects or patients and when designing simulation models of human balance.


Assuntos
Retroalimentação Sensorial/fisiologia , Equilíbrio Postural/fisiologia , Tempo de Reação/fisiologia , Privação Sensorial/fisiologia , Percepção do Tato/fisiologia , Adulto , Feminino , Humanos , Masculino , Fatores de Tempo , Adulto Jovem
10.
J Neurooncol ; 108(2): 247-52, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22350377

RESUMO

Neuropsychological testing is not a luxury in the management of patients with brain tumors. Regardless of the therapeutic approach selected in each case (but, especially in the case of awake surgery), it provides information on the status of language and other cognitive functions. This information can be used preoperatively to identify eloquent areas and to provide a baseline against which further examinations can be evaluated, intraoperatively to identify eloquent areas, and post-operatively and at follow-up to ascertain the short-term and long-term consequences of surgery, as well as those of other treatments (chemotherapy and radiotherapy), and to plan and monitor rehabilitative treatments.


Assuntos
Neoplasias Encefálicas/complicações , Transtornos da Linguagem/etiologia , Testes de Linguagem , Humanos
11.
Phys Med Biol ; 57(5): 1399-412, 2012 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-22349550

RESUMO

The aim of this study was to develop a model exploiting artificial neural networks (ANNs) to correlate dosimetric and clinical variables with late rectal bleeding in prostate cancer patients undergoing radical radiotherapy and to compare the ANN results with those of a standard logistic regression (LR) analysis. 718 men included in the AIROPROS 0102 trial were analyzed. This multicenter protocol was characterized by the prospective evaluation of rectal toxicity, with a minimum follow-up of 36 months. Radiotherapy doses were between 70 and 80 Gy. Information was recorded for comorbidity, previous abdominal surgery, use of drugs and hormonal therapy. For each patient, a rectal dose-volume histogram (DVH) of the whole treatment was recorded and the equivalent uniform dose (EUD) evaluated as an effective descriptor of the whole DVH. Late rectal bleeding of grade ≥ 2 was considered to define positive events in this study (52 of 718 patients). The overall population was split into training and verification sets, both of which were involved in model instruction, and a test set, used to evaluate the predictive power of the model with independent data. Fourfold cross-validation was also used to provide realistic results for the full dataset. The LR was performed on the same data. Five variables were selected to predict late rectal bleeding: EUD, abdominal surgery, presence of hemorrhoids, use of anticoagulants and androgen deprivation. Following a receiver operating characteristic analysis of the independent test set, the areas under the curves (AUCs) were 0.704 and 0.655 for ANN and LR, respectively. When evaluated with cross-validation, the AUC was 0.714 for ANN and 0.636 for LR, which differed at a significance level of p = 0.03. When a practical discrimination threshold was selected, ANN could classify data with sensitivity and specificity both equal to 68.0%, whereas these values were 61.5% for LR. These data provide reasonable evidence that results obtained with ANNs are superior to those achieved with LR when predicting late radiotherapy-related rectal bleeding. The future introduction of patient-related personal characteristics, such as gene expression profiles, might improve the predictive power of statistical classifiers. More refined morphological aspects of the dose distribution, such as dose surface mapping, might also enhance the overall performance of ANN-based predictive models.


Assuntos
Imageamento Tridimensional/métodos , Neoplasias da Próstata/radioterapia , Lesões por Radiação/diagnóstico , Radioterapia Conformacional/métodos , Doenças Retais/diagnóstico , Área Sob a Curva , Hemorragia , Humanos , Masculino , Redes Neurais de Computação , Probabilidade , Curva ROC , Radiometria/métodos , Dosagem Radioterapêutica , Radioterapia Conformacional/efeitos adversos , Análise de Regressão , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
12.
Eur J Phys Rehabil Med ; 47(1): 101-21, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21448123

RESUMO

The aim of the study was to evaluate the efficacy of the treatment for language and calculation disorders and for speech apraxia in vascular subjects. Only therapeutic methods that could be qualified as neuropsychological were taken into account. For language disorders, we searched the pertinent literature published from 1950 to August 31, 2007 by means of electronic data banks and we took into consideration the Cochrane review, and papers in Cicerone et al. and Cappa et al. systematic reviews. For acalculia we examined the literature from 1980 by carrying out research on electronic data banks; for speech apraxia, studies emerged from a search of PUBMED. Aphasia therapy has been clearly demonstrated efficacious in groups of subjects if sufficiently prolonged/intensive. Treatment for specific disorders (words and sentences processing, reading, writing) studied in series of single patients, though always efficacious, reaches a lower level of recommendation due to the lack of RCT. Only a few studies tackled the problem of efficacy in case of speech apraxia and calculation disorders. Results are positive but data are scanty. Efficacy of aphasia therapy seems well established in group of subjects and well-promising for speech apraxia and calculation disorders. It is suggested, however, that the term "aphasia" covers widely different impairments and that RCT are not the best instrument to evaluate efficacy; the importance of chronicity is underlined.


Assuntos
Apraxias/reabilitação , Transtornos Cerebrovasculares/reabilitação , Transtornos da Linguagem/reabilitação , Agrafia/reabilitação , Afasia/reabilitação , Transtornos Cerebrovasculares/complicações , Dislexia/reabilitação , Humanos , Conceitos Matemáticos , Distúrbios da Fala/reabilitação , Resultado do Tratamento
13.
J Biomech ; 42(14): 2268-72, 2009 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-19682691

RESUMO

Wearing sport shoes inducing ankle dorsiflexion has been shown to alter the biomechanical specificities of the stretched muscles. The possible effect over the short and long term upon the sensorial capacities induced by such stretching has not been addressed yet. Fourteen healthy individuals were involved to assess the proprioceptive repercussion and their effects upon postural control strategies. Postural control and proprioceptive assessment were measured twice: when receiving sport shoes inducing ankle dorsiflexion and 18 days later. Proprioceptive effects were assessed using an ad-hoc device through which the seated and blindfolded subjects were required to reposition their feet in a starting position after the ankles were passively displaced to dorsiflexed and plantarflexed positions. Center-of-gravity horizontal displacements (CG(v)), estimated from center-of-pressure (CP) displacements, and CP-CG(v) displacements were measured through a force platform during upright quiet stance maintenance. The initial session was recorded with the subjects barefoot and wearing the shoes with a set of chocks with 0 degrees (horizontal) and -5 degrees (dorsiflexion) tilting angles. The second session included only barefoot performance in horizontal and dorsiflexion conditions. Dorsiflexion had no immediate effect on the postural control strategies along the anteroposterior axis. In contrast, barefoot or wearing shoes, stability was increased along the mediolateral axis during the dorsiflexion conditions. No ankle proprioceptive or postural change was observed after wearing the shoes for 18 days. Wearing dorsiflexion sport shoes induces short-term effects probably by inducing a backward tilt of the pelvis. A muscular adaptation likely prevents this effect from being prolonged.


Assuntos
Articulação do Tornozelo/fisiologia , Movimento/fisiologia , Equilíbrio Postural/fisiologia , Postura/fisiologia , Sapatos , Equipamentos Esportivos , Adaptação Fisiológica/fisiologia , Adulto , Humanos , Masculino , Fatores de Tempo , Adulto Jovem
14.
Bioresour Technol ; 99(16): 7425-32, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18387801

RESUMO

A considerable number of studies has been conducted on switchgrass (Panicum virgatum L.) as a bioresource for energy over the last few years. Nonetheless, some important issues concerning the agro-technique are still open. This research examines the long-term total dry matter yield (TDM) and ash content of two lowland (L) and two upland (U) switchgrass cytotypes, as affected by one or two-cut system, under southern EU climatic conditions (44 degrees 33' N). Overall, L produced higher TDM than U (on average 14.9 and 11.7 Mg ha(-1), respectively); two-cut system allowed to produce higher biomass yields (especially in U) than single harvest during the two first years, but it also drastically reduced plant vigour and productivity of all cytotypes in the following two years. Moreover, under two-cut system almost total seasonal biomass derived from the early harvest, while the second cut slightly contributed to the total seasonal biomass, nor it appeared to offset the additional harvest costs. Biomass quality was also significantly affected by cutting frequency, with two-cut system leading to a considerably higher ash content of biomass. Therefore, it is perceived that two-cut system is not worthwhile with U and L cytotypes as bioresource for energy production under southern EU conditions.


Assuntos
Fontes Geradoras de Energia/economia , Panicum/crescimento & desenvolvimento , Agricultura/métodos , Biomassa , Clima , Eficiência , Fontes Geradoras de Energia/estatística & dados numéricos , Geografia , Panicum/classificação , Estações do Ano
15.
J Neurol Neurosurg Psychiatry ; 79(4): 451-3, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18096677

RESUMO

Transcranial direct current stimulation (tDCS) has been proposed as an adjuvant technique to improve functional recovery after ischaemic stroke. This study evaluated the effect of tDCS over the left frontotemporal areas in eight chronic non-fluent post-stroke aphasic patients. The protocol consisted of the assessment of picture naming (accuracy and response time) before and immediately after anodal or cathodal tDCS (2 mA, 10 minutes) and sham stimulation. Whereas anodal tDCS and sham tDCS failed to induce any changes, cathodal tDCS significantly improved the accuracy of the picture naming task by a mean of 33.6% (SEM 13.8%).


Assuntos
Anomia/terapia , Afasia de Broca/terapia , Infarto Cerebral/complicações , Terapia por Estimulação Elétrica/métodos , Lobo Frontal/fisiopatologia , Lobo Occipital/fisiopatologia , Lobo Temporal/fisiopatologia , Idoso , Anomia/fisiopatologia , Afasia de Broca/fisiopatologia , Infarto Cerebral/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reconhecimento Visual de Modelos/fisiologia , Tempo de Reação/fisiologia , Semântica , Medida da Produção da Fala , Resultado do Tratamento
16.
Minerva Med ; 98(1): 77-80, 2007 Feb.
Artigo em Italiano | MEDLINE | ID: mdl-17372584

RESUMO

Activated C protein resistance is a common coagulation defect caused by factor V Leiden mutation and is associated with an augmented risk of predominantly venous thrombosis. Augmented tendency to arterial thrombosis is sporadically reported. This case report describes femoropopliteal thrombosis in a young patient with heterozygous V Leiden factor mutation. Progressive thrombotic occlusion required amputation of the forefoot which resulted in stump dehiscence. Poor blood supply to the perilesional substrate delayed wound healing. An optimal though not yet definitive result was achieved after months of accurate medication. The criticality of lower limb ischemia in an otherwise healthy young patient underscores the grave impact this condition can have on the patient's quality of life and on health care costs.


Assuntos
Fator V/genética , Artéria Femoral , Mutação , Artéria Poplítea , Trombose/genética , Resistência à Proteína C Ativada/genética , Adulto , Amputação Cirúrgica/efeitos adversos , Amputação Cirúrgica/métodos , Heterozigoto , Humanos , Masculino , Trombose/complicações , Trombose/cirurgia , Cicatrização
17.
J Exp Bot ; 57(6): 1253-62, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16467409

RESUMO

Stable carbon isotope discrimination (delta13C), photosynthetic performance (A), dry matter accumulation (DW), and sucrose yield (Y(s)) of sugar beet were evaluated in a glasshouse experiment under transient (TS) and permanent (PS) water stress. A was significantly reduced under drought, to an extent depending on stress duration. The reduced A was strictly associated with a low DW and Y(s), the later being 42% lower in PS than control plants (C). Restoring water steeply increased A and the associated leaf traits (RWC, leaf water potential etc.), but the increase of Y(s) was negligible. Therefore, the negative effects of severe water stress in the early growth period, though reversible on gas-exchange and most leaf traits, can drastically reduce Y(s) of sugar beet. Furthermore, A seems not to be effective in predicting sucrose accumulation, although it was very effective in detecting the occurrence of plant water stress. The A/C(i) model was used to assess the photosynthetic adjustments to continuous or transient drought by calculating the photosynthetic parameters Vcmax and Jmax and then compared with delta13C. Mesophyll conductance (g(m)) was estimated by comparing delta13C measured on soluble sugars and gas-exchange data. This approach confirmed the expectation that g(m) was limiting A and that there was a significant drop in [CO2] from the substomatal cavities and the chloroplast stroma both in favourable and drought conditions. Therefore, the carbon concentration at the carboxylation site was overestimated by 25-35% by conventional gas-exchange measurements, and Vcmax was consistently underestimated when g(m) was not taken into account, especially under severe drought. Root delta13C was found to be strictly related to sucrose content (brix%), Y(s) and root dry weight, and this was especially clear when delta13C was measured on bulk dry matter. By contrast, leaf delta13C measured in soluble sugars (delta(s)) and bulk dry matter (delta(dm)) were found to correlate weakly to brix% and yield, and this was not surprising as the integration time-scale of leaf delta(s) and delta(dm) were found to be shorter than that of root delta13C in bulk dry matter. The effect of water stress on diffusive and biochemical limitations with different integration times ranged from 1 d (leaf delta(s)) to more than 1 month (root delta(dm)).


Assuntos
Beta vulgaris/fisiologia , Água/fisiologia , Beta vulgaris/crescimento & desenvolvimento , Isótopos de Carbono/metabolismo , Fotossíntese , Folhas de Planta/crescimento & desenvolvimento , Sacarose/metabolismo
18.
Cardiovasc Radiat Med ; 5(2): 71-6, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15464943

RESUMO

PURPOSE: Based on our preclinic studies with autologous unfractionated bone marrow (AUBM) via coronary sinus with transitory occlusion, a clinic study in patients with chronic stable angina was designed. The objectives were to evaluate safety, tolerance and feasibility. METHODS AND MATERIALS: A multicenter prospective study with inclusion and exclusion criteria defined by an Independent Clinical Committee was carried out. Fourteen patients underwent transcoronary sinus administration of freshly aspirated and filtered AUBM (60-120 ml). Safety and tolerance were evaluated. Feasibility was evaluated with Seattle Angina Questionnaire (SAQ), Canadian Cardiovascular Society (CCS) angina classification (baseline-Day 180), myocardial perfusion (baseline-Day 90) with independent core laboratory and coronary angiography (baseline and Day 30). RESULTS: There were no changes in the safety and tolerance parameters. Preliminary clinical efficacy at Day 180 disclosed a significant improvement of 38%, evaluated by the SAQ. The CCS angina classification shows that the mean angina class was 3.0+/-0.55 at baseline and improved to 2.0+/-0.00 at Day 180 (P <.001). Semiquantitative radionuclide perfusion imaging (core lab) showed a significant improvement at Day 90 in 13/14 patients, with a mean improvement of 24% at rest (P <.01) and 33% at stress (P <.05). Coronary angiography showed more collateral vessels in 9/14 patients. CONCLUSIONS: We can conclude that AUBM via coronary sinus with transitory occlusion is tolerable and safe. Significant improvement in the myocardial perfusion at Day 90 and in the quality of life at Day 180 was observed.


Assuntos
Angina Pectoris/terapia , Transplante de Medula Óssea/métodos , Vasos Coronários , Angina Pectoris/complicações , Transplante de Medula Óssea/efeitos adversos , Doença Crônica , Angiografia Coronária/métodos , Doença da Artéria Coronariana/complicações , Circulação Coronária , Estudos de Viabilidade , Feminino , Coração/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Transplante Autólogo , Resultado do Tratamento
19.
Water Sci Technol ; 49(11-12): 53-60, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15303723

RESUMO

Nitrogen can be eliminated effectively from sludge digester effluents by anaerobic ammonium oxidation (anammox), but 55-60% of the ammonium must first be oxidized to nitrite. Although a continuous flow stirred tank reactor (CSTR) with suspended biomass could be used, its hydraulic dilution rate is limited to 0.8-1 d(-1) (30 degrees C). Higher specific nitrite production rates can be achieved by sludge retention, as shown here for a moving-bed biofilm reactor (MBBR) with Kaldnes carriers on laboratory and pilot scales. The maximum nitrite production rate amounted to 2.7 gNO2-Nm(-2)d(-1) (3 gO2m(-3)d(-1), 30.5 degrees C), thus doubling the dilution rate compared to CSTR operation with suspended biomass for a supernatant with 700 gNH4-Nm(-3). Whenever the available alkalinity was fully consumed, an optimal amount of nitrite was produced. However, a significant amount of nitrate was produced after 11 months of operation, making the effluent unsuitable for anaerobic ammonium oxidation. Because the sludge retention time (SRT) is relatively long in biofilm systems, slow growth of nitrite oxidizers occurs. None of the selection criteria applied - a high ammonium loading rate, high free ammonia or low oxygen concentration - led to selective suppression of nitrite oxidation. A CSTR or SBR with suspended biomass is consequently recommended for full-scale operation.


Assuntos
Biofilmes , Nitrogênio/isolamento & purificação , Compostos de Amônio Quaternário/metabolismo , Esgotos/química , Esgotos/microbiologia , Bactérias Anaeróbias , Biomassa , Nitritos/análise , Nitritos/química , Nitrogênio/química , Nitrogênio/metabolismo , Oxirredução
20.
Eur J Heart Fail ; 4(5): 617-25, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12413506

RESUMO

AIMS: With the complex demodulation (CDM) method, we assessed the instantaneous amplitude and frequency of cardiovascular (CV) and respiratory oscillations, and the instant phase (IP) between the CV and respiratory signals using respiration as a periodic forced stimulation. We hypothesised a possible lack of synchronisation between CV and respiratory signals under regular breathing at different frequencies. METHODS: RR interval (ECG), blood pressure (SBP/DBP, Finapress), respiration (Respitrace) were monitored during two random-order periods of voluntary paced-breathing (0.15 Hz/0.25 Hz) in 10 moderate CHF patients and 10 age-matched controls. The CDM method provides the amplitude and frequency of a particular spectral component as a function of time in both LF and HF bands. IP between CV and respiratory oscillations was assessed using the real modulating breathing rate. RESULTS: (i) Continuous phase variations between CV oscillations and the respiratory signal were evidenced in CHF patients, the slower the breathing rate, the greater the phase variation (RR/Resp; 0.25 Hz, 23+/-17 degrees; 0.15 Hz, 46+/-57 degrees, P<0.01; RR/Resp at 0.15 Hz 6+/-3 vs. 46+/-57 P<0.01 controls vs. CHF). Phase was constant in controls. (ii) In patients, the instant amplitude of the cardiovascular oscillations in the high frequency domain is more markedly altered when the breathing rate was slowed down as compared to controls. CONCLUSION: The lack of synchronisation between physiological signals during voluntary breathing in CHF patients highlights a central uncoupling between CV and respiratory neuronal activities.


Assuntos
Sistema Cardiovascular/fisiopatologia , Insuficiência Cardíaca/fisiopatologia , Sistema Respiratório/fisiopatologia , Adulto , Pressão Sanguínea/fisiologia , Doença Crônica , Eletrocardiografia , Feminino , Insuficiência Cardíaca/terapia , Ventilação de Alta Frequência , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Respiração , Sístole/fisiologia , Fatores de Tempo
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