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1.
Sci Rep ; 12(1): 19343, 2022 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-36369462

RESUMO

This study was designed to investigate the feasibility and the potential effects on walking performance of a short gait training with a novel impairment-specific hip assistance (iHA) through a bilateral active pelvis orthosis (APO) in patients with acquired brain injury (ABI). Fourteen subjects capable of independent gait and exhibiting mild-to-moderate gait deficits, due to an ABI, were enrolled. Subjects presenting deficit in hip flexion and/or extension were included and divided into two groups based on the presence (group A, n = 6) or absence (group B, n = 8) of knee hyperextension during stance phase of walking. Two iHA-based profiles were developed for the groups. The protocol included two overground gait training sessions using APO, and two evaluation sessions, pre and post training. Primary outcomes were pre vs. post-training walking distance and steady-state speed in the 6-min walking test. Secondary outcomes were self-selected speed, joint kinematics and kinetics, gait symmetry and forward propulsion, assessed through 3D gait analysis. Following the training, study participants significantly increased the walked distance and average steady-state speed in the 6-min walking tests, both when walking with and without the APO. The increased walked distance surpassed the minimal clinically important difference for groups A and B, (respectively, 42 and 57 m > 34 m). In group A, five out of six subjects had decreased knee hyperextension at the post-training session (on average the peak of the knee extension angle was reduced by 36%). Knee flexion during swing phase increased, by 16% and 31%, for A and B groups respectively. Two-day gait training with APO providing iHA was effective and safe in improving walking performance and knee kinematics in ABI survivors. These preliminary findings suggest that this strategy may be viable for subject-specific post-ABI gait rehabilitation.


Assuntos
Lesões Encefálicas , Exoesqueleto Energizado , Humanos , Estudos de Viabilidade , Marcha , Caminhada , Fenômenos Biomecânicos
2.
Front Robot AI ; 9: 951663, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36105761

RESUMO

This study describes the software methodology designed for systematic benchmarking of bipedal systems through the computation of performance indicators from data collected during an experimentation stage. Under the umbrella of the European project Eurobench, we collected approximately 30 protocols with related testbeds and scoring algorithms, aiming at characterizing the performances of humanoids, exoskeletons, and/or prosthesis under different conditions. The main challenge addressed in this study concerns the standardization of the scoring process to permit a systematic benchmark of the experiments. The complexity of this process is mainly due to the lack of consistency in how to store and organize experimental data, how to define the input and output of benchmarking algorithms, and how to implement these algorithms. We propose a simple but efficient methodology for preparing scoring algorithms, to ensure reproducibility and replicability of results. This methodology mainly constrains the interface of the software and enables the engineer to develop his/her metric in his/her favorite language. Continuous integration and deployment tools are then used to verify the replicability of the software and to generate an executable instance independent of the language through dockerization. This article presents this methodology and points at all the metrics and documentation repositories designed with this policy in Eurobench. Applying this approach to other protocols and metrics would ease the reproduction, replication, and comparison of experiments.

3.
J Neuroeng Rehabil ; 18(1): 111, 2021 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-34217307

RESUMO

BACKGROUND: Transfemoral amputation is a serious intervention that alters the locomotion pattern, leading to secondary disorders and reduced quality of life. The outcomes of current gait rehabilitation for TFAs seem to be highly dependent on factors such as the duration and intensity of the treatment and the age or etiology of the patient. Although the use of robotic assistance for prosthetic gait rehabilitation has been limited, robotic technologies have demonstrated positive rehabilitative effects for other mobility disorders and may thus offer a promising solution for the restoration of healthy gait in TFAs. This study therefore explored the feasibility of using a bilateral powered hip orthosis (APO) to train the gait of community-ambulating TFAs and the effects on their walking abilities. METHODS: Seven participants (46-71 years old with different mobility levels) were included in the study and assigned to one of two groups (namely Symmetry and Speed groups) according to their prosthesis type, mobility level, and prior experience with the exoskeleton. Each participant engaged in a maximum of 12 sessions, divided into one Enrollment session, one Tuning session, two Assessment sessions (conducted before and after the training program), and eight Training sessions, each consisting of 20 minutes of robotically assisted overground walking combined with additional tasks. The two groups were assisted by different torque-phase profiles, aiming at improving symmetry for the Symmetry group and at maximizing the net power transferred by the APO for the Speed group. During the Assessment sessions, participants performed two 6-min walking tests (6mWTs), one with (Exo) and one without (NoExo) the exoskeleton, at either maximal (Symmetry group) or self-selected (Speed group) speed. Spatio-temporal gait parameters were recorded by commercial measurement equipment as well as by the APO sensors, and metabolic efficiency was estimated via the Cost of Transport (CoT). Additionally, kinetic and kinematic data were recorded before and after treatment in the NoExo condition. RESULTS: The one-month training protocol was found to be a feasible strategy to train TFAs, as all participants smoothly completed the clinical protocol with no relevant mechanical failures of the APO. The walking performance of participants improved after the training. During the 6mWT in NoExo, participants in the Symmetry and Speed groups respectively walked 17.4% and 11.7% farther and increased walking speed by 13.7% and 17.9%, with improved temporal and spatial symmetry for the former group and decreased energetic expenditure for the latter. Gait analysis showed that ankle power, step width, and hip kinematics were modified towards healthy reference levels in both groups. In the Exo condition metabolic efficiency was reduced by 3% for the Symmetry group and more than 20% for the Speed group. CONCLUSIONS: This study presents the first pilot study to apply a wearable robotic orthosis (APO) to assist TFAs in an overground gait rehabilitation program. The proposed APO-assisted training program was demonstrated as a feasible strategy to train TFAs in a rehabilitation setting. Subjects improved their walking abilities, although further studies are required to evaluate the effectiveness of the APO compared to other gait interventions. Future protocols will include a lighter version of the APO along with optimized assistive strategies.


Assuntos
Amputados , Robótica , Idoso , Marcha , Humanos , Pessoa de Meia-Idade , Aparelhos Ortopédicos , Projetos Piloto , Qualidade de Vida , Caminhada
4.
IEEE Trans Neural Syst Rehabil Eng ; 28(7): 1573-1583, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32634096

RESUMO

Benchmarks have long been used to verify and compare the readiness level of different technologies in many application domains. In the field of wearable robots, the lack of a recognized benchmarking methodology is one important impediment that may hamper the efficient translation of research prototypes into actual products. At the same time, an exponentially growing number of research studies are addressing the problem of quantifying the performance of robotic exoskeletons, resulting in a rich and highly heterogeneous picture of methods, variables and protocols. This review aims to organize this information, and identify the most promising performance indicators that can be converted into practical benchmarks. We focus our analysis on lower limb functions, including a wide spectrum of motor skills and performance indicators. We found that, in general, the evaluation of lower limb exoskeletons is still largely focused on straight walking, with poor coverage of most of the basic motor skills that make up the activities of daily life. Our analysis also reveals a clear bias towards generic kinematics and kinetic indicators, in spite of the metrics of human-robot interaction. Based on these results, we identify and discuss a number of promising research directions that may help the community to attain a comprehensive benchmarking methodology for robot-assisted locomotion more efficiently.


Assuntos
Exoesqueleto Energizado , Fenômenos Biomecânicos , Humanos , Locomoção , Extremidade Inferior , Caminhada
5.
Waste Manag ; 68: 198-206, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28669494

RESUMO

Municipal Solid Waste (MSW) refers to a heterogeneous mixture composed of plastics, paper, metal, food and other miscellaneous items. Local authorities commonly dispose of this waste by either landfill or incineration which are both unsustainable practices. Disposing of organic wastes via these routes is also becoming increasingly expensive due to rising landfill taxes and transport costs. The Thermo-Catalytic Reforming (TCR®) process, is a proposed valorisation route to transform organic wastes and residues, such as MSW, into sustainable energy vectors including (H2 rich synthesis gas, liquid bio-oil and solid char). The aim herein, was to investigate the conversion of the organic fraction of MSW into fuels and chemicals utilising the TCR technology in a 2kg/h continuous pilot scale reactor. Findings show that MSW was successfully processed with the TCR after carrying out a feedstock pre-treatment step. Approximately, 25wt.% of the feedstock was converted into phase separated liquids, composed of 19wt.% aqueous phase and 6wt.% organic phase bio-oil. The analysis of the bio-oil fraction revealed physical and chemical fuel properties, higher heating value (HHV) of 38MJ/kg, oxygen content <7wt.% and water content <4wt.%. Due to the bio-oil's chemical and physical properties, the bio-oil was found to be directly miscible with fossil diesel when blended at a volume ratio of 50:50. The mass balance closure was 44wt.% synthesis gas, with a H2 content of 36vol% and HHV of 17.23MJ/Nm3, and 31 wt.% char with a HHV of 17MJ/kg. The production of high quantities of H2 gas and highly de-oxygenated organic liquids makes downstream hydrogen separation and subsequent hydro-deoxygenation of the produced bio-oil a promising upgrading step to achieve drop-in transportation fuels from MSW.


Assuntos
Resíduos Sólidos , Biocombustíveis , Catálise , Incineração , Óleos , Plásticos
6.
Bioresour Technol ; 222: 148-155, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27721094

RESUMO

The study evaluated the growth of Desmodesmus communis on column photobioreactor and its thermochemical treatment by catalytic pyrolysis using HZSM-5 zeolite. D. communis showed good results in terms of growth (0.05gL-1d-1). Analytical pyrolysis of original algae and derived bio-oil mixed with zeolite was used as a screening method in order to gather information on the cracking process. Preparative pyrolysis on bench scale reactor was performed on algae biomass over a zeolite bed at 1:10 ratio (wt/wt). Py-GC-MS of biomass/catalyst mixture showed that the denitrogenation/deoxygenation increased with increasing zeolite load from 1:5 to 1:20 ratio and became significant at 1:10 ratio. The composition observed by analytical pyrolysis was featured by the predominance of alkylated monoaromatic hydrocarbons. The scaling-up to bench scale confirmed the results obtained with analytical pyrolysis in terms of monoaromatic hydrocarbons. However, low yield of catalytic oil (8% by weight) was observed.


Assuntos
Biotecnologia/métodos , Clorófitas/metabolismo , Hidrocarbonetos/metabolismo , Microalgas/metabolismo , Biocombustíveis/análise , Biomassa , Biotecnologia/instrumentação , Catálise , Clorófitas/química , Clorófitas/crescimento & desenvolvimento , Cromatografia Gasosa-Espectrometria de Massas/métodos , Hidrocarbonetos/análise , Hidrocarbonetos/química , Microalgas/química , Microalgas/crescimento & desenvolvimento , Fotobiorreatores , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Zeolitas/química
7.
Bioresour Technol ; 191: 117-23, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25983230

RESUMO

The microalgae Botryococcus braunii is widely recognized as a potentially important biofuel-feedstock whose commercial exploitation is limited by difficulties with its cultivation and harvesting. In this study, two B. braunii strains, Kossou-4 and Overjuyo-3 were successfully cultured at a 500 l-scale for 60-days. Harvesting by bio-flocculation with Aspergillus fumigatus at an optimum ratio of 1:40 of fungus to microalgal culture resulted in up to 98% recovery of biomass in the two strains. Ultimate analysis (C, N, H, S, ash, high heating value) and pyrolysis (analytical and preparative pyrolysis and GC-MS assays) showed that co-harvesting with fungi did not cause any impairment of the feedstock value of the microalgal biomass. This work represents the first report on the successful culturing and harvesting of these strains at a 500 l-scale using bio-flocculation. The use of A. fumigatus represents an efficient and economical method for the harvest of B. braunii for biofuel production.


Assuntos
Biocombustíveis/microbiologia , Clorófitas/crescimento & desenvolvimento , Microalgas/crescimento & desenvolvimento , Aspergillus fumigatus/crescimento & desenvolvimento , Biomassa , Floculação
8.
Med Dosim ; 39(3): 276-81, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25088815

RESUMO

The purpose of this study was to perform delivery quality assurance with ArcCHECK and 3DVH system (Sun Nuclear, FL) and to evaluate the suitability of this system for volumetric-modulated arc therapy (VMAT) (RapidArc [RA]) verification. This software calculates the delivered dose distributions in patients by perturbing the calculated dose using errors detected in fluence or planar dose measurements. The device is tested to correlate the gamma passing rate (%GP) and the composite dose predicted by 3DVH software. A total of 28 patients with prostate cancer who were treated with RA were analyzed. RA treatments were delivered to a diode array phantom (ArcCHECK), which was used to create a planned dose perturbation (PDP) file. The 3DVH analysis used the dose differences derived from comparing the measured dose with the treatment planning system (TPS)-calculated doses to perturb the initial TPS-calculated dose. The 3DVH then overlays the resultant dose on the patient's structures using the resultant "PDP" beams. Measured dose distributions were compared with the calculated ones using the gamma index (GI) method by applying the global (Van Dyk) normalization and acceptance criteria, i.e., 3%/3mm. Paired differences tests were used to estimate statistical significance of the differences between the composite dose calculated using 3DVH and %GP. Also, statistical correlation by means of logistic regression analysis has been analyzed. Dose-volume histogram (DVH) analysis for patient plans revealed small differences between treatment plan calculations and 3DVH results for organ at risk (OAR), whereas planning target volume (PTV) of the measured plan was systematically higher than that predicted by the TPS. The t-test results between the planned and the estimated DVH values showed that mean values were incomparable (p < 0.05). The quality assurance (QA) gamma analysis 3%/3mm showed that in all cases there were only weak-to-moderate correlations (Pearson r: 0.12 to 0.74). Moreover, clinically relevant differences increased with increasing QA passing rate, indicating that some of the largest dose differences occurred in the cases of high QA passing rates, which may be called "false negatives." The clinical importance of any disagreement between the measured and the calculated dose is often difficult to interpret; however, beam errors (either in delivery or in TPS calculation) can affect the effectiveness of the patient dose. Further research is needed to determinate the role of a PDP-type algorithm to accurately estimate patient dose effect.


Assuntos
Neoplasias da Próstata/radioterapia , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada , Software , Humanos , Masculino , Garantia da Qualidade dos Cuidados de Saúde
10.
Diabetes ; 60(2): 644-51, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21270274

RESUMO

OBJECTIVE: We have developed a new antihyperglycemic agent (teglicar) through the selective and reversible inhibition of the liver isoform of carnitine palmitoyl-transferase 1 (L-CPT1). RESEARCH DESIGN AND METHODS: Glucose production was investigated in isolated hepatocytes and during pancreatic clamps in healthy rats. Chronic treatments on C57BL/6J, db/db, high-fat fed mice, and rats were performed to understand glucose metabolism and insulin sensitivity. RESULTS: In isolated hepatocytes, teglicar concentration dependently reduced ketone bodies and glucose production up to 72 and 50%, respectively. In rats, teglicar reduced the endogenous glucose production (-62%) without affecting peripheral glucose utilization. Heart 2-[(3)H]deoxyglucose uptake in mice was also not affected, confirming in vivo the drug selectivity toward L-CPT1. Chronic treatment in db/db mice (50 mg/kg/bid; 45 days) reduced postabsorptive glycemia (-38%), water consumption (-31%), and fructosamine (-30%). Such antidiabetic activity was associated with an improved insulin sensitivity assessed by the insulin tolerance test. A significant 50% increase in hepatic triglyceride content (HTGC) was found, although plasma alanineaminotransferase was not altered. In addition, long-term teglicar administration to high-fat fed C57BL/6J mice normalized glycemia (-19%) and insulinemia (-53%). Long-term teglicar administration (30 days, 80 mg/kg) in healthy overnight-fasted rats slightly reduced basal glycemia (-20%, ns), reduced basal insulin levels by 60%, doubled triglycerides, and increased free-fatty acids (+53%). HTGC was markedly increased, but liver and peripheral insulin sensitivity assessed by hyperinsulinemiceuglycemic clamp were not affected. CONCLUSIONS: Teglicar, in vitro and in animal models, reduces gluconeogenesis and improves glucose homeostasis, refreshing the interest in selective and reversible L-CPT1 inhibition as a potential antihyperglycemic approach.


Assuntos
Carnitina O-Palmitoiltransferase/antagonistas & inibidores , Carnitina/análogos & derivados , Gluconeogênese/efeitos dos fármacos , Glucose/metabolismo , Homeostase/efeitos dos fármacos , Fígado/efeitos dos fármacos , Análise de Variância , Animais , Área Sob a Curva , Carnitina/farmacologia , Diabetes Mellitus Tipo 2/metabolismo , Gorduras na Dieta/metabolismo , Coração/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Resistência à Insulina , Fígado/metabolismo , Masculino , Camundongos , Miocárdio/metabolismo , PPAR alfa/metabolismo , Ratos , Ratos Sprague-Dawley
11.
Psychopharmacology (Berl) ; 210(1): 85-95, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20232053

RESUMO

RATIONALE: Neurons detect free fatty acids (FFAs) availability and use this nutritional status to modulate feeding and control body weight. OBJECTIVES: The work is designed to characterize the impact on feeding behavior of either oleic acid (OA) administration (experiment 1) or the inhibition (experiment 2) of the enzyme carnitine palmitoyltransferase-1 (CPT-1). The structure of feeding behavior and satiation time course were examined through the behavioral satiety sequence (BSS) paradigm. METHODS: Adult male mice were initially habituated to a palatable diet, then subjected to intracerebroventricular (i.c.v.) infusion of different doses of OA or the CPT-1 inhibitor ST1326. Food intake at different time points, duration, and frequencies of feeding and non-feeding-related behaviors were continuously monitored over 40 min and satiety development profiled according to BSS. RESULTS: Intra-i.c.v. infusion of oleic acid (300 nM) and ST1326 (50 and 75 pM) suppressed food intake. As indicated by the earlier leftward shifting of the normal transition from eating to resting, both strategies similarly accelerated the onset of satiety. The premature onset of satiety resulted in a dose-related fashion with 50 pM of ST1326 producing a marked premature onset than the lower dose. However, at the highest dose injected, the inhibition of CPT-1 disrupted the BSS profile. CONCLUSIONS: The increased neuronal availability of FFAs mediates a significant anorectic response which is mirrored by an early occurrence of satiety onset. Besides supporting the role of central nutrient sensing in feeding, the present data demonstrate that the modulation of satiety enhancement can produce appetite suppressant effects within narrow range of neuronal FFAs availability.


Assuntos
Ingestão de Alimentos/efeitos dos fármacos , Ingestão de Alimentos/fisiologia , Ácidos Graxos não Esterificados/administração & dosagem , Neurônios/metabolismo , Resposta de Saciedade/efeitos dos fármacos , Resposta de Saciedade/fisiologia , Animais , Ácidos Graxos não Esterificados/metabolismo , Comportamento Alimentar/efeitos dos fármacos , Comportamento Alimentar/fisiologia , Injeções Intraventriculares , Masculino , Camundongos
13.
J Clin Psychopharmacol ; 29(6): 576-83, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19910724

RESUMO

The aim of this study was to model in mice the association between metabolic syndrome and the administration of atypical antipsychotic (AAP). Two dosages (4 and 8 mg/kg per day) of olanzapine (OL) were infused in 36 female mice for 30 days by osmotic mini-pumps. This study was also designed to further extend the implications raised in other experiments by our model of AAP-induced metabolic dysregulation. Through the use of the osmotic mini-pumps, this model is aimed to circumvent the shorter (than in humans) half-life of AAPs in rodents and to chronically administer OL by a reliable and less disturbing method. Indirect calorimetry was used to evaluate metabolic rate (MR) and respiratory exchange ratio together with weight and caloric intake. Serum insulin, leptin, and glucose tolerance (oral glucose tolerance test) were assessed. Pancreatic beta cells insulin levels, periuterine and liver fat content were also analyzed. Olanzapine-infused mice exhibited a reduction of overall MR (kilojoule per hour) and resting MR and respiratory exchange ratio, with periuterine fat significantly enlarged. All metabolic alterations were detected at the highest dose, with major effects found on weight gain and hyperphagia. Impaired glucose metabolism, associated with hyperinsulinemia and hyperleptinemia were found. Insulin resistance was evidenced by the raise of HOMA-IR index. Increased insulin and lipid storage were detected at pancreatic and hepatic levels respectively. These findings illustrate the development of a cluster of risk factors (metabolic syndrome) and, for the first time, a decrease of energy expenditure (MR) due to chronic OL infusion.


Assuntos
Benzodiazepinas/administração & dosagem , Benzodiazepinas/efeitos adversos , Dislipidemias/sangue , Metabolismo Energético/fisiologia , Intolerância à Glucose/sangue , Resistência à Insulina/fisiologia , Animais , Peso Corporal/efeitos dos fármacos , Peso Corporal/fisiologia , Dislipidemias/induzido quimicamente , Metabolismo Energético/efeitos dos fármacos , Feminino , Intolerância à Glucose/induzido quimicamente , Bombas de Infusão Implantáveis , Infusões Intravenosas , Síndrome Metabólica/sangue , Síndrome Metabólica/induzido quimicamente , Camundongos , Olanzapina , Fatores de Tempo
14.
J Pharmacol Exp Ther ; 326(3): 905-11, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18567835

RESUMO

A mouse model of atypical antipsychotic-associated adverse effects was used to compare the liability to induce weight gain, food intake, and metabolic alterations after chronic olanzapine (OL; LY170053, 2-methyl-4-(4-methyl-1-piperazinyl)-10H-thieno-[2,3-b][1,5] benzodiazepine) and ST2472 (ST; 9-piperazin-1-ylpyrrolo[2,1-b][1,3]benzothiazepine) administration. By adding two equipotent doses (3 and 6 mg/kg) of either OL or ST to a high-sweet, high-fat (HS-HF) diet, mice were allowed to self-administer drugs up to 50 days. Body weight and food intake were evaluated daily. Locomotor activity was recorded over 48 h at two different time points. Dyslipidemia was measured by central visceral obesity. Blood serum levels of insulin (IN), glucose (Glu), triglycerides (TGs), nonesterified fatty acids (NEFAs), cholesterol (Ch), and ketone (Ke) bodies were quantified. OL treatment at 3 mg/kg enhanced body weight, whereas at the highest dose, the increase became evident only during the last 10 days of treatment. OL (3 mg/kg) increased HS-HF intake over time, whereas the highest dose reduced intake during the second 10 and final 10 days of administration. Both compounds induced nocturnal hypomotility at the highest dose. In contrast to ST, 3 mg/kg OL elevated serum levels of IN, Glu, TG, NEFA, Ch, and Ke, whereas 6 mg/kg OL elevated those of Glu, TG, and Ch. In contrast, ST did not affect weight gain, food intake, and metabolic markers. Given the similarities between OL-induced obesogenic effects and medical reports, this study further supports the view that ST may represent a new class of agents characterized by a low propensity to induce side effects with promising clinical safety.


Assuntos
Benzodiazepinas/administração & dosagem , Hiperfagia/induzido quimicamente , Doenças Metabólicas/induzido quimicamente , Piperazinas/administração & dosagem , Pirróis/administração & dosagem , Tiazepinas/administração & dosagem , Aumento de Peso/efeitos dos fármacos , Animais , Benzodiazepinas/efeitos adversos , Peso Corporal/efeitos dos fármacos , Peso Corporal/fisiologia , Hiperfagia/metabolismo , Doenças Metabólicas/metabolismo , Camundongos , Olanzapina , Piperazinas/efeitos adversos , Pirróis/efeitos adversos , Tiazepinas/efeitos adversos , Aumento de Peso/fisiologia
15.
Appl. cancer res ; 28(1): 24-28, 2008.
Artigo em Inglês | LILACS, Inca | ID: lil-504011

RESUMO

Soft tissue sarcomas are rare tumors that represents less than 1% of all neoplasms and only 5.3% of these tumors arises in the chest wall. After resection of these tumors, the defects generated by radical surgery especially when sternum or three or more ribs are resected represent a challenge to the surgeons because of the defect itself and pulmonary physiology alterations. The authors describe a new three-layer technique for chest wall reconstruction, based upon steel stitches, polypropylene mesh and myocutaneous flaps performed in six consecutive patients.


Assuntos
Humanos , Cirurgia Geral , Sarcoma , Tórax
16.
Nat Med ; 9(6): 756-61, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12754501

RESUMO

The enzyme carnitine palmitoyltransferase-1 (CPT1) regulates long-chain fatty acid (LCFA) entry into mitochondria, where the LCFAs undergo beta-oxidation. To investigate the mechanism(s) by which central metabolism of lipids can modulate energy balance, we selectively reduced lipid oxidation in the hypothalamus. We decreased the activity of CPT1 by administering to rats a ribozyme-containing plasmid designed specifically to decrease the expression of this enzyme or by infusing pharmacological inhibitors of its activity into the third cerebral ventricle. Either genetic or biochemical inhibition of hypothalamic CPT1 activity was sufficient to substantially diminish food intake and endogenous glucose production. These results indicated that changes in the rate of lipid oxidation in selective hypothalamic neurons signaled nutrient availability to the hypothalamus, which in turn modulated the exogenous and endogenous inputs of nutrients into the circulation.


Assuntos
Carnitina O-Palmitoiltransferase/metabolismo , Ingestão de Alimentos , Glucose/metabolismo , Hipotálamo/enzimologia , Proteína Relacionada com Agouti , Animais , Sequência de Bases , Carnitina O-Palmitoiltransferase/antagonistas & inibidores , Carnitina O-Palmitoiltransferase/genética , Ácidos Graxos/metabolismo , Insulina/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular , Fígado/metabolismo , Masculino , Neuropeptídeo Y/metabolismo , Conformação de Ácido Nucleico , Oxirredução , Proteínas/metabolismo , RNA Catalítico/metabolismo , Ratos , Ratos Sprague-Dawley
17.
J Med Chem ; 46(2): 303-9, 2003 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-12519067

RESUMO

The synthesis and pharmacological activity of reversible CPT I inhibitors as potential antiketotic and antidiabetic drugs are reported. Such inhibitors constitute a series of enantiomerically pure aminocarnitine derivatives having the general formula (CH3)3N+CH2CH(ZR)CH2COO- (with Z = ureido, carbamate, sulfonamide, and sulfamide moieties; R = C7-C14 linear alkyl chains). A primary pharmacological screening based on the evaluation of CPT I activity in intact rat liver (L-CPT I) mitochondria revealed the best activity for the (R) forms of ureidic derivative 17 (ZR = NHCONHR, R = C14), sulfonamidic derivative 7 (ZR = NHSO2R, R = C12), and sulfamidic derivative 9 (ZR = NHSO2NHR, R = C11). The IC50 values are 1.1, 0.7, and 0.8 microM, respectively. For the carbamic derivative 11 (ZR = NHCOOR, R = C8), an IC50 of 9.5 microM was observed. In addition, an extraordinarily high selectivity toward the liver isoform with respect to the heart isoform (muscle-CPT I identical with M-CPT I) was found for the ureidic compound 17 (IC50(M-CPT I) vs IC50(L-CPTI) = 39.4), as well as for other ureidic or carbamic compounds. Diabetic db/db mice treated orally with 17 and 7 for 45 days at a dose of 50 mg/kg twice a day showed a good reduction of serum glucose levels with respect to the untreated db/db mice (p < 0.01). In addition, 17 showed antiketotic activity in normal fasted rats. 17 has been selected for development as a potential antiketotic and antidiabetic drug.


Assuntos
Butiratos/síntese química , Carnitina O-Palmitoiltransferase/antagonistas & inibidores , Carnitina/análogos & derivados , Carnitina/síntese química , Inibidores Enzimáticos/síntese química , Hipoglicemiantes/síntese química , Compostos de Amônio Quaternário/síntese química , Ácido 3-Hidroxibutírico/sangue , Animais , Glicemia/análise , Butiratos/farmacologia , Carnitina/metabolismo , Carnitina/farmacologia , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/tratamento farmacológico , Inibidores Enzimáticos/farmacologia , Jejum , Hipoglicemiantes/farmacologia , Técnicas In Vitro , Isoenzimas/antagonistas & inibidores , Cetose/tratamento farmacológico , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias Cardíacas/efeitos dos fármacos , Mitocôndrias Cardíacas/enzimologia , Mitocôndrias Hepáticas/efeitos dos fármacos , Mitocôndrias Hepáticas/enzimologia , Compostos de Amônio Quaternário/farmacologia , Ratos , Ratos Sprague-Dawley , Estereoisomerismo , Relação Estrutura-Atividade
18.
Paciente crit. (Uruguay) ; 15(1/3): 24-33, 2002. ilus, tab, graf
Artigo em Espanhol | LILACS | ID: lil-351124

RESUMO

La nutrición enteral (NE) ha sido jerarquizada recientemente no sólo por su importancia nutricional, sino también por su efecto inmunomodulador en los pacientes críticos. Esto ha llevado al inicio de la misma en forma precoz, aún en pacientes con enfermedad aguda abdominal como peritonitis y pancreatitis. Esto está en contra de la conducta habitual en nuestro medio, donde los pacientes con pancreatitis aguda (PA) son habitualmente sometidos a largos períodos de nutrición parenteral total (NPT). Es así que decidimos iniciar un protocolo de NE temprana en pacientes con PA mediante la colocación de una sonda nasoyeyunal bajo control radioscópico y evaluar los resultados del seguimiento de los primeros 35 casos. Se incluyeron un total de 35 pacientes con PA, de las cuales 21 fueron catalogadas como grave en base al score de gravedad APACHE II o a la clasificación tomográfica de Baltasar, o ambas. La nutrición se inició dentro de los cinco días de ingreso a la unidad con fórmulas poliméricas. Se realizó un corte evolutivo el día de inicio de la nutrición (DO), a los siete días (D7) y a los 14 días de seguimiento (D14), donde se evaluó APACHE II, tomografía axial computarizada abdominal, glicemia, calcemia, amilasemia, residual gástrico y eventuales complicaciones evolutivas. Las curvas de APACHE II y amilasemia mostraron una tendencia descendente a lo largo de los 14 días de seguimiento. La TAC de abdomen evidenció mejoría o el mismo grado de Balthazar en 80 por ciento de los casos. La evolución metabólica fue hacia la estabilización de los parámetros evaluados. Evolucionaron a la mejoría 84 por ciento de los pacientes evaluados. Concluímos por tanto que la nutrición yeyunal precoz es viable en el curso de una pancreatitis aguda grave sin determinar una reactivación de la enfermedad


Assuntos
Humanos , Masculino , Adolescente , Adulto , Feminino , Pessoa de Meia-Idade , Nutrição Enteral/métodos , Pancreatite , Doença Aguda , Jejuno
19.
Rev. bras. mastologia ; 10(1): 43-5, mar. 2000. ilus
Artigo em Português | LILACS | ID: lil-277364

RESUMO

Os sarcomas de mama säo tumores de rara ocorrência, representando aproximadamente 0,04 por cento das neoplasias do órgäo. Entre os sarcomas mamários, o angiossarcoma é um dos menos frequentes. Relatamos um caso de angiossarcoma primário da mama, ocorrido em uma paciente de 36 anos, de cor parda, localizado na mama esquerda, que se apresentava como um tumor de 6,0cm x 5,0cm em seus maiores diâmetros. Apresentou crescimento rápido, sendo que o diagnóstico foi firmado por estudo histológico pela biópsia histológica por agulha grossa (biopty-cut). A paciente foi submetida à mastetomia simples e quimioterapia, evoluindo com metástases à distância, e óbito em 18 meses após o diagnóstico


Assuntos
Humanos , Feminino , Adulto , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/terapia , Hemangiossarcoma/diagnóstico , Hemangiossarcoma/terapia , Biópsia por Agulha , Mastectomia Simples
20.
Rev. bras. ginecol. obstet ; 17(6): 663-5, jul. 1995. ilus
Artigo em Português | LILACS | ID: lil-165271

RESUMO

É relatado um caso de mastite tuberculosa em uma paciente de 72 anos. O quadro clínico constituiu-se de um nódulo de 6 x 6 cm, sem sinais flogísticos. Com suspeita clínica de carcinoma, a paciente foi submetida à tumorectomia. O exame anátomopatológico revelou processo granulomatoso crônico, tendo sido demonstrada a presença do bacilo álcool-ácido-resistente. A mastite tuberculosa é abordada sob os pontos de vista etiopatogênico, taxinômico, clínico e terapêutico.


Assuntos
Humanos , Feminino , Idoso , Mastite/microbiologia , Mastite/patologia , Tuberculose/patologia , Biópsia por Agulha , Mastite/tratamento farmacológico , Tuberculose/tratamento farmacológico
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