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1.
bioRxiv ; 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-37205497

RESUMO

Natural behaviors have redundancy, which implies that humans and animals can achieve their goals with different control objectives. Given only observations of behavior, is it possible to infer the control strategy that the subject is employing? This challenge is particularly acute in animal behavior because we cannot ask or instruct the subject to use a particular control strategy. This study presents a threepronged approach to infer an animal's control strategy from behavior. First, both humans and monkeys performed a virtual balancing task for which different control objectives could be utilized. Under matched experimental conditions, corresponding behaviors were observed in humans and monkeys. Second, a generative model was developed that represented two main control strategies to achieve the task goal. Model simulations were used to identify aspects of behavior that could distinguish which control objective was being used. Third, these behavioral signatures allowed us to infer the control objective used by human subjects who had been instructed to use one control objective or the other. Based on this validation, we could then infer strategies from animal subjects. Being able to positively identify a subject's control objective from behavior can provide a powerful tool to neurophysiologists as they seek the neural mechanisms of sensorimotor coordination.

2.
Neural Comput ; 35(5): 853-895, 2023 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-36944234

RESUMO

Humans are adept at a wide variety of motor skills, including the handling of complex objects and using tools. Advances to understand the control of voluntary goal-directed movements have focused on simple behaviors such as reaching, uncoupled to any additional object dynamics. Under these simplified conditions, basic elements of motor control, such as the roles of body mechanics, objective functions, and sensory feedback, have been characterized. However, these elements have mostly been examined in isolation, and the interactions between these elements have received less attention. This study examined a task with internal dynamics, inspired by the daily skill of transporting a cup of coffee, with additional expected or unexpected perturbations to probe the structure of the controller. Using optimal feedback control (OFC) as the basis, it proved necessary to endow the model of the body with mechanical impedance to generate the kinematic features observed in the human experimental data. The addition of mechanical impedance revealed that simulated movements were no longer sensitively dependent on the objective function, a highly debated cornerstone of optimal control. Further, feedforward replay of the control inputs was similarly successful in coping with perturbations as when feedback, or sensory information, was included. These findings suggest that when the control model incorporates a representation of the mechanical properties of the limb, that is, embodies its dynamics, the specific objective function and sensory feedback become less critical, and complex interactions with dynamic objects can be successfully managed.


Assuntos
Retroalimentação Sensorial , Movimento , Humanos , Retroalimentação , Destreza Motora , Fenômenos Biomecânicos
3.
Heliyon ; 9(1): e12854, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36685414

RESUMO

Ceramic grade red iron oxide (α-Fe2O3) nanoparticles pigments have been synthesized from waste condensed milk containers which contain a prominent amount of iron (93.2%). The synthesis method comprised of two steps: in the first step ferrous sulfate was prepared following an acid leaching method; while the second step was oxidation and calcination of ferrous sulfate to produce desired α-Fe2O3 in nano form. The structure, functional groups, chemical state, morphology, particle size, surface area, elemental, thermal analysis and magnetic properties of the samples were investigated using XRD, FTIR, XPS, SEM, BET, EDS, TG-DT and VSM respectively. Pure hematite (α-Fe2O3) phase was confirmed by XRD and the average crystal sizes were in the range 34-126 nm have been performed by Debye-Scherer's formula, which are consistent with the results as achieved from SEM images. Agglomerated irregular spherical nanoparticles (45-149 nm) were found in SEM image. The surface chemistry and the chemical state (Fe3+) of the hematite nanoparticles was also confirmed by XPS. The mesoporous nature of the nanoparticles with high surface area were measured by BET and it has been revealed that the BET specific surface area (33.55 m2/g) was marginally higher than the commercial one. The magnetic nature of the nanoparticles was portrayed by VSM and the nanoparticles showed the ferromagnetic behavior. Moreover, particle size distributions and zeta potential values have been also measured by DLS.

4.
Pak J Biol Sci ; 26(11): 549-556, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38193369

RESUMO

<b>Background and Objective:</b> Fixed oils used in traditional therapies also called volatile oils are generally aromatic oils obtained by the steam or hydrodistillation of plants. Different parts of plants have been used to obtain fixed oils. This study estimates the chemical constituents and <i>in vitro</i> antibacterial activity of fixed oils extracted by petroleum ether from the leaves, roots, stems and fruit part of <i>Bridelia stipularis</i> (L.). <b>Materials and Methods:</b> The natural fatty acids were extracted from different parts of <i>B. stipularis</i> by using petroleum ether. The fixed oils were studied by gas chromatography-mass spectrophotometry. The antibacterial test was carried out by the agar disc diffusion method. A Student's t-test was computed for the statistical significance of the results. <b>Results:</b> It showed 10 compounds from the leaf and 5 compounds from the stem. In both cases, the major components were methyl decanoate 93.56 and 74.98%, respectively. From the root parts, 6 compounds were identified in which the major compound was methyl linolelaidate (36.86%). Two compounds were identified from the fruit part and the major portion was methyl pentadecanoate (98.20%). The <i>in vitro</i> antibacterial potentials of the oils were tested against four pathogenic bacteria. Among the four fixed oils, the stem, leaf and root showed the strongest activity against <i>E. coli</i> (30, 21 and 15 mm). On the other hand, fruit fixed oil showed the highest zone of inhibition against <i>Bacillus cereus</i> (25 mm). <b>Conclusion:</b> The fixed oils of <i>B. stipularis</i> plant have the potential to be applied as an antibacterial agent, which can be selected for further analysis and can be used to discover bioactive natural products that may serve as leads in the development of new pharmaceuticals that address unmet therapeutic needs.


Assuntos
Escherichia coli , Óleos Voláteis , Alcanos , Óleos Voláteis/farmacologia , Antibacterianos/farmacologia , Ácidos Graxos
5.
IEEE Trans Biomed Eng ; 69(2): 975-982, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34495828

RESUMO

A human hand is a complex biomechanical system, in which bones, ligaments, and musculotendon units dynamically interact to produce seemingly simple motions. A new physiological hand simulator has been developed, in which electromechanical actuators apply load to the tendons of extrinsic hand and wrist muscles to recreate movements in cadaveric specimens in a biofidelic way. This novel simulator simultaneously and independently controls the movements of the wrist (flexion/extension and radio-ulnar deviation) and flexion/extension of the fingers and thumb. Control of these four degrees of freedom (DOF) is made possible by actuating eleven extrinsic muscles of the hand. The coupled dynamics of the wrist, fingers, and thumb, and the over-actuated nature of the human musculoskeletal system make feedback control of hand movements challenging. Two control algorithms were developed and tested. The optimal controller relies on an optimization algorithm to calculate the required tendon tensions using the collective error in all DOFs, and the action-based controller loads the tendons solely based on their actions on the controlled DOFs (e.g., activating all flexors if a flexing moment is required). Both controllers resulted in hand movements with small errors from the reference trajectories ( ); however, the optimal controller achieved this with 16% lower total force. Owing to its simpler structure, the action-based controller was extended to enable feedback control of grip force. This simulator has been shown to be a highly repeatable tool (  N and variations in force and kinematics, respectively) for in vitro analyses of human hand biomechanics.


Assuntos
Mãos , Punho , Mãos/fisiologia , Força da Mão/fisiologia , Humanos , Movimento/fisiologia , Punho/fisiologia , Articulação do Punho
6.
Asian Pac J Cancer Prev ; 21(6): 1511-1519, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32592343

RESUMO

BACKGROUND: A transversion missense polymorphism of the TP53 tumor suppressor gene at the codon 72 codes proline instead of arginine causes an altered p53 protein expression and has been found to be associated with an elevated risk of various cancer; especially breast and lung cancer. As the previous case-control studies on the South Asian population have shown controversial results, we performed a meta-analysis to evaluate a precise estimation of the relationship between the TP53 Arg72Pro polymorphism with breast and lung cancer. METHODS: A total of 12 related studies on the South Asian population have been included through comprehensive database searching. Six studies were selected for breast cancer meta-analysis involving 950 cases and 882 controls; the other six studies were for lung cancer meta-analysis including 975 cases and 1397 controls. The results have been determined by using the Review Manager (RevMan) 5.3. Additionally, the stability of our analysis was assessed by heterogeneity, publication bias analysis and sensitivity testing. RESULTS: A significantly increased risk of breast cancer was found in Pro allele (Pro vs. Arg), co-dominant model 2 (Pro/Pro vs. Arg/Arg), dominant model (Pro/Pro + Arg/Pro vs. Arg/Arg). In case of lung cancer, significantly increased risk was found in the allele, co-dominant 1, co-dominant 2, co-dominant 3, dominant, and recessive models. No association with other genetic models with breast and lung cancer risk was found in the South Asian population. CONCLUSIONS: Our results indicate that TP53 Arg72Pro polymorphism is a risk factor for the development of breast cancer and lung cancer in the South Asian population.


Assuntos
Neoplasias da Mama/epidemiologia , Códon/genética , Predisposição Genética para Doença , Neoplasias Pulmonares/epidemiologia , Polimorfismo de Nucleotídeo Único , Proteína Supressora de Tumor p53/genética , Ásia/epidemiologia , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Estudos de Casos e Controles , Feminino , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Prognóstico , Fatores de Risco
7.
IEEE Int Conf Rehabil Robot ; 2017: 1451-1456, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28814024

RESUMO

Functional electrical stimulation (FES) is a type of neuroprosthesis in which muscles are stimulated by electrical pulses in order to compensate for the loss of voluntary movement control. Modulating the stimulation intensities to reliably generate movements is a challenging control problem. For the first time, this paper presents a feedback controller for FES to control arm movements in a 2D (table-top) task space. This feedback controller is based on a recent human motor control model, which uses muscle synergies to simplify the calculations and improve control performance. The experimental results show that this control scheme can produce arbitrary movements in the 2D task space, with less than 2 cm hand position error from the specified targets.


Assuntos
Estimulação Elétrica/métodos , Retroalimentação , Músculo Esquelético/fisiologia , Extremidade Superior/fisiologia , Adulto , Estimulação Elétrica/instrumentação , Humanos , Masculino , Sistemas Homem-Máquina , Processamento de Sinais Assistido por Computador
8.
J BUON ; 21(6): 1433-1441, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28039704

RESUMO

PURPOSE: To investigate the association of ABCB1-C3435T transition with breast cancer risk which was followed by a meta-analysis. METHODS: In a case-control study we collected blood samples from 290 women (including 150 breast cancer patients and 140 healthy controls). ABCB1-C3435T genotyping was performed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. A meta-analysis was performed for a total of 13 eligible studies involving 5,835 cases and 8,178 controls. RESULTS: The results of case-control study revealed a significant association between T allele (OR=1.770, 95%CI=1.236-2.535, p=0.002), CT genotype (OR=1.661, 95%CI=1.017-2.713, p=0.042), and TT genotype (OR=3.399, 95%CI=1.409-8.197, p=0.006) with breast cancer risk. Data from meta-analysis revealed a significant association between ABCB1-C3435T polymorphism and breast cancer risk in allelic (OR=1.243, 95%CI=1.079-1.432, p=0.003), co-dominant (OR=1.349, 95%CI=1.042-1.746, p=0.023), dominant (OR=1.204, 95%CI=1.019-1.422, p=0.029), and recessive (OR=1.226, 95%CI=1.011-1.488, p=0.039) models. CONCLUSIONS: The results suggest that the ABCB1-C3435T gene polymorphism might be a genetic risk factor and a potential biomarker for breast cancer.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Polimorfismo de Nucleotídeo Único , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Neoplasias da Mama/etnologia , Neoplasias da Mama/patologia , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Feminino , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Heterozigoto , Homozigoto , Humanos , Razão de Chances , Fenótipo , Medição de Risco , Fatores de Risco
9.
Braz. arch. biol. technol ; 59: e16160223, 2016. tab, graf
Artigo em Inglês | LILACS | ID: biblio-951331

RESUMO

ABSTRACT This study was designed to examine the chemical composition and in vitro antioxidant activity of the hydrodistillated essential oil and various extracts obtained from Premna integrifolia Linn. GC-MS analysis of the essential oil was resulted in determination 29 different compounds, representing 95.73% of total oil. Antioxidant activities of the essential oil and organic extracts of chloroform, ethyl acetate and methanol were determined by three different test systems namely DPPH (2,2-diphenyl-1-picrylhydrazyl), superoxide and nitric oxide radical scavenging assays. The essential oil and methanol extract showed potent antioxidant activity among all the tested samples. Furthermore, the amount of total phenolic compounds was determined and its content in methanol extract was the highest as compared to other samples. The results indicate that the essential oil and extracts of Premna integrifolia could serve as an important bio-resource of antioxidants for using in the pharmaceutical industries.

10.
Glob J Health Sci ; 8(6): 196-202, 2015 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-26755458

RESUMO

INTRODUCTION: Given that nurses are among professions with frequent problems of fatigue, and given the nature of their profession that provides little exposure to sunlight and the subsequent deficiency of vitamin D, the present study examined the relation between fatigue and circulating vitamin D levels in female nurses working in Shahid Beheshti Hospital, Kashan, Iran in 2013. MATERIAL & METHODS: This cross-sectional study was conducted in 200 female nurses working in Shahid Beheshti Hospital. To measure fatigue, fatigue questionnaire containing 9 questions eliciting the subject's feeling in scales of 1 to 7, getting a possible score of 9 to 63, and Visual Analogue Scale in which nurses specified their fatigue in a band of zero to 10 were used. The 25-hydroxyvitamin D, which is the most important vitamin D metabolite, also was determined. The data was analyzed by SPSS-16. The Pearson's correlation of coefficients, t-test, and multiple regression analysis were used in this study. RESULTS: The mean fatigue score of nurses was 38.76±12.66 in questionnaire and 5.73±2.12 in Visual Analog Scale. The 89 per cent of nurses suffered from vitamin D deficiency, 9.5 percent of them had normal level and 1.5 per cent had toxicity level of vitamin D. There was a significant relationship between vitamin D level and fatigue scores (P<0.0001), and visual fatigue scores (P<0.0001). According to multivariate regression analysis, vitamin D level accounted for 13 per cent of the fatigue based on data on questionnaire and 18.6 per cent of fatigue according to Visual Analog Scale. CONCLUSION: High prevalence of fatigue among nurses could be attributed to vitamin D deficiency.


Assuntos
Fadiga/sangue , Fadiga/epidemiologia , Enfermeiras e Enfermeiros/estatística & dados numéricos , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/epidemiologia , Vitamina D/sangue , Adulto , Comorbidade , Estudos Transversais , Feminino , Humanos , Irã (Geográfico)/epidemiologia , Pessoa de Meia-Idade , Prevalência , Adulto Jovem
11.
Iran J Basic Med Sci ; 17(4): 250-5, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24904717

RESUMO

OBJECTIVES: Regulatory T cells, including CD4+CD25+Fox3+ and CD8+CD28- cells play an important role in regulating the balance between immunity and tolerance. Since multiple sclerosis is an inflammatory autoimmune disease, regulatory T cells are considered to be involved in its pathogenesis. In this study, we investigated the circulatory numbers of the two mentioned types of regulatory T cells and also their association with different clinical characteristics in 84 multiple sclerosis patients. MATERIALS AND METHODS: 84 patients with multiple sclerosis and 75 normal individuals were studied. Demographic and clinical information of all participants were collected via questionnaire and clinical examination as well as MRI. The peripheral blood frequency of two different subgroups of regulatory T cells (CD4+ CD25+Foxp3+ and CD8+CD28- cells) were analyzed by flow cytometry using anti-human antibodies conjugated with CD4-FITC / CD25-PE/Foxp3-PE-Cy5, CD3-PE/CD8a-PE-Cy5/CD28-FITC. RESULTS: The frequency of CD4+CD25+Foxp3+ cells in multiple sclerosis patients was significantly less than that in healthy controls (P=0.006) and in mild forms less than that in sever forms (P=0.003). There was not any correlation between the frequency of regulatory T cells and different clinical variables. CONCLUSION: Our results showed that the number of CD4+CD25+Foxp3+ cells decreases significantly in multiple sclerosis patients, which probably shows the regulatory role of these cells in multiple sclerosis.

12.
Sensors (Basel) ; 14(3): 4342-63, 2014 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-24599193

RESUMO

Human motion is a daily and rhythmic activity. The exoskeleton concept is a very positive scientific approach for human rehabilitation in case of lower limb impairment. Although the exoskeleton shows potential, it is not yet applied extensively in clinical rehabilitation. In this research, a fuzzy based control algorithm is proposed for lower limb exoskeletons during sit-to-stand and stand-to-sit movements. Surface electromyograms (EMGs) are acquired from the vastus lateralis muscle using a wearable EMG sensor. The resultant acceleration angle along the z-axis is determined from a kinematics sensor. Twenty volunteers were chosen to perform the experiments. The whole experiment was accomplished in two phases. In the first phase, acceleration angles and EMG data were acquired from the volunteers during both sit-to-stand and stand-to-sit motions. During sit-to-stand movements, the average acceleration angle at activation was 11°-48° and the EMG varied from -0.19 mV to +0.19 mV. On the other hand, during stand-to-sit movements, the average acceleration angle was found to be 57.5°-108° at the activation point and the EMG varied from -0.32 mV to +0.32 mV. In the second phase, a fuzzy controller was designed from the experimental data. The controller was tested and validated with both offline and real time data using LabVIEW.


Assuntos
Lógica Fuzzy , Extremidade Inferior/fisiologia , Movimento/fisiologia , Postura/fisiologia , Telemetria/instrumentação , Aceleração , Adulto , Fenômenos Biomecânicos , Sistemas Computacionais , Eletrodos , Eletromiografia , Humanos , Masculino , Músculo Esquelético/fisiologia , Processamento de Sinais Assistido por Computador , Adulto Jovem
13.
EXCLI J ; 13: 427-36, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-26417269

RESUMO

The antifungal potential of essential oil and ethanolic leaf extracts of Lonicera japonica Thunb. was evaluated for controlling the growth of dermatophytes. The oil (1,000 ppm) and extracts (1,500 ppm) of L. japonica revealed 55.1-70.3 % and 40.1-65.5 % antidermatophytic effect against Microsporum canis KCTC 6348, 6349, 6591, Trichophyton rubrum KCTC 6345, 6352, 6375, Trichophyton mentagrophytes KCTC 6077 and 6085, respectively, along with their respective minimum inhibitory concentrations ranging from 62.5-500 and 125-1,000 µg/ml. Also, the oil had strong detrimental effect on spore germination of all the tested dermatophytes as well as concentration and time-dependent kinetic inhibition of M. canis KCTC 6348. The results demonstrated that L. japonica oil and extracts could be potential sources of natural fungicides to protect human and animals from fungal infections.

14.
EXCLI J ; 13: 1104-10, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-26417325

RESUMO

The secondary metabolites such as essential oil and pure compounds (limonin and imperatorin) from Poncirus trifoliata Rafin were tested for in vitro control of phytopathogenic bacteria of Xanthomonas spp. In vitro studies showed that the oil had inhibitory effect on Xanthomonas campestris pv. compestris KC94-17-XCC, Xanthomonas campestris pv. vesicatoria YK93-4-XCV, Xanthomonas oryzae pv. oryzae KX019-XCO and Xanthomonas sp. SK12 with their inhibition zones and minimum inhibitory concentration (MIC) values ranging from 13.1~22.1 mm and 62.5~125 µg/ml, respectively. Limonin and imperatorin also had in vitro antibacterial potential (MIC: 15.62~62.5 µg/ml) against all the tested Xanthomonas spp. Furthermore, the SEM studies demonstrated that limonin and imperatorin caused morphological changes of Xanthomonas sp. SK12 at the minimum inhibitory concentration (15.62 µg/ml). These results of this study support the possible use of essential oil and natural compounds from P. Trifoliata in agriculture and agro-industries to control plant pathogenic microorganisms.

15.
Chinese Journal of Traumatology ; (6): 323-326, 2014.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-316878

RESUMO

<p><b>OBJECTIVE</b>Among the injury types, sports ones constitute a considerable proportion of patients who refer to the medical centers. This research was conducted to examine the frequency of sports-related injuries referring to Kashan University of Medical Sciences Trauma Research Center from 2005 to 2011.</p><p><b>METHODS</b>This was a retrospective research in which existing data from the data bank of Kashan University of Medical Sciences Trauma Research Center were employed. The data were extracted from the main source by SPSS version 16.0. Variables such as age, education, occupation and gender were analyzed.</p><p><b>RESULTS</b>The highest proportion of injuries was observed in students (59.4%) followed by workers (11.8%). Upper and lower extremities were most commonly injured. The most frequent injury was strain (35.4%), followed by sprain (27.7%).</p><p><b>CONCLUSION</b>The results of this research showed that the majority of the sports trauma occurrs in students; therefore, they need more attention in regard to sports injuries. Preventive measures such as informing the coaches and teachers as well as increasing the students'awareness about the injury risk can decrease the incidences of sports injuries.</p>


Assuntos
Humanos , Traumatismos em Atletas , Epidemiologia , Irã (Geográfico) , Epidemiologia , Estudos Retrospectivos , Estudantes
16.
Res Dev Disabil ; 34(12): 4304-9, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24157403

RESUMO

In this study we examined the effects of physical training and calcium intake on the development of bone mineral density (BMD) in children with Down syndrome (DS). A total of 48 children with DS (age 7-12 years old) matched for age and BMD were assigned to four groups exercise and calcium intake (Ex(+)Ca(+)), calcium intake-no-exercise (Ex(-)Ca(+)), exercise no-calcium intake (Ex(+)Ca(-)) and non-exercise-no-calcium intake (Ex(-)Ca(-)). The training protocol included 45 min of weight bearing exercise performed 3 sessions per week in addition to dietary calcium rich food intake of enriched cow milk with vitamin D containing 200 mg calcium per serving or no enriched dietary supplement for a duration of 4 months. Data analysis was performed on data by using t-test, one-way ANOVA analysis and Tukey post hoc tests to determine the main and combined effects of training and calcium regiment on BMD. All groups showed greater femoral neck BMD after 4 months. The increase in femoral neck BMD in the Ex(+)Ca(+) group was 5.96% greater than the Ex(+)Ca(-) group (p<0.01). The effect of training was greater than calcium intake alone. The Ex(+)Ca(-) group achieved 3.52% greater BMD than Ex(-)Ca(+) group (p<0.01). In this study, all the experimental groups had greater BMD than the no-calcium-no-exercise group that served as the control group (p<0.01). It was concluded that additional weight bearing exercise and calcium supplementation resulted in a greater increase in BMD in children with DS.


Assuntos
Densidade Óssea , Cálcio da Dieta/uso terapêutico , Síndrome de Down , Alimentos Fortificados , Osteoporose/prevenção & controle , Treinamento Resistido/métodos , Desenvolvimento Ósseo , Criança , Síndrome de Down/complicações , Humanos , Osteoporose/complicações , Resultado do Tratamento
17.
Food Chem Toxicol ; 48(6): 1757-60, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20385198

RESUMO

The chemical composition of the hydro-distilled essential oil from leaves of Curcuma aromatica Salisb. was analysed by GC-MS. Twenty-three compounds representing 94.29% of the total oil were identified. The antioxidant activities of the oil and various extracts of C. aromatica were evaluated by using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and superoxide radical-scavenging assays. The oil and methanol extract showed potent DPPH radical-scavenging activities (IC(50)=14.45 and 16.58 microg/ml, respectively), which were higher than butylated hydroxyanisole (IC(50)=18.27 microg/ml). The extracts also exhibited remarkable superoxide radical-scavenging activities (IC(50)=22.6-45.27 microg/ml) and the activity in the methanol extract was superior to all other extracts (IC(50)=22.6 microg/ml). Furthermore, the amount of total phenolic compounds was determined and its content in ethyl acetate extract was the highest as compared to other extracts. The results indicate that the oil and extracts of C. aromatica could serve as an important bio-resource of antioxidants for using in the food industries.


Assuntos
Antioxidantes/farmacologia , Óleos Voláteis/farmacologia , Zingiberaceae/química , Cromatografia Gasosa-Espectrometria de Massas
18.
Food Chem Toxicol ; 48(5): 1350-4, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20206225

RESUMO

This study was undertaken to examine the efficacy of essential oil from seeds of Zizyphus jujuba for its potential role on hair growth by in vivo method. Essential oil was applied at different concentrations (0.1%, 1% and 10%) over the shaved skin onto the backs of BALB/c mice and monitored for 21 days. After 21 days, mice treated with 1% and 10% of oil produced a greater effect on the length of hair which were measured to be 9.96 and 10.02 mm, respectively, as compared to the control (8.94 mm). We measured the weight of hair/cm(2) area of dorsal skin and also evaluated hair thickness and hair follicles microscopically after plucking the hair immediately from the shaved area of mice and found the best results for 1% of essential oil-treated mice. From this study, it is concluded that Z. jujuba essential oil possesses hair growth promoting activity.


Assuntos
Cabelo/efeitos dos fármacos , Óleos Voláteis/farmacologia , Óleos de Plantas/farmacologia , Ziziphus/química , Animais , Feminino , Cabelo/crescimento & desenvolvimento , Folículo Piloso/efeitos dos fármacos , Folículo Piloso/crescimento & desenvolvimento , Camundongos , Camundongos Endogâmicos BALB C , Extratos Vegetais/farmacologia , Sementes/química , Pele/efeitos dos fármacos
19.
Food Chem Toxicol ; 48(2): 639-43, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19944733

RESUMO

This study was undertaken to evaluate the effect of essential oil from seeds of Zizyphus jujuba on TPA-induced skin inflammation in experimental mice. Exposure of TPA on the ear of the BALB/c mice caused a marked increase in both ear thickness and skin water content. The ear thickness was measured for TPA-induced ear was 0.54 mm, as compared to control (0.23 mm). Treatment with 1% and 10% of essential oil caused significant decrease in ear thicknesses which were measured to be 0.30 and 0.35 mm, as well as reduce the water content about 51% and 53% in the TPA-induced skin inflammation model, respectively. Furthermore, histological analysis clearly confirmed that Z. jujuba essential oil inhibited the inflammatory responses of skin inflammation in animal model. Therefore, our findings demonstrate that the essential oil of Z. jujuba seeds might accelerate the development of new drugs for various inflammatory diseases.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Otite Externa/tratamento farmacológico , Óleos de Plantas/farmacologia , Ziziphus/química , Animais , Modelos Animais de Doenças , Orelha Externa/efeitos dos fármacos , Edema/induzido quimicamente , Edema/tratamento farmacológico , Edema/patologia , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Otite Externa/induzido quimicamente , Otite Externa/patologia , Óleos de Plantas/química , Sementes/química , Acetato de Tetradecanoilforbol/farmacologia
20.
Food Chem Toxicol ; 48(2): 549-52, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19932731

RESUMO

Six compounds, namely, Lupeol (1), Betulin (2), beta-Taraxerol (3), Taraxerone (4), Stigmasterol (5) and beta-Sitosterol (6) were isolated from the petroleum ether extract of the leaves of Sapium baccatum based on spectroscopic evidence. Lupeol (1), Betulin (2) and Stigmasterol (5) were isolated for the first time from this plant. The cytotoxic potential of the different solvent extracts (methanol, petroleum ether, carbon-tetrachloride and dichloromethane); six column fractions (F-4, F-7, F-10, F-12, F-18 and F-22) of petroleum ether extract and three pure compounds 1, 4 and 6 were determined by using brine shrimp lethality bioassay. The LC50 of all the tested samples were showed to be lethal to brine shrimp nauplii. However, petroleum ether, carbon-tetrachloride extract, column fractions F-4 and F-18 of petroleum ether extract and pure compound 6 showed quite potent activity in brine shrimp lethality bioassay with LC50 1.33, 1.35, 1.40, 1.58 and 1.58 microg/ml, respectively. These result suggested that they might be contain antitumor or pesticidal activity. Further, the methanol extract and four column fractions (F-7, F-12, F-18 and F-22) of petroleum ether showed significant activity against the tested microorganisms.


Assuntos
Antibacterianos/farmacologia , Citotoxinas/farmacologia , Extratos Vegetais/farmacologia , Sapium/química , Animais , Artemia/efeitos dos fármacos , Fracionamento Químico , Longevidade/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Folhas de Planta/química , Solventes/química , Testes de Toxicidade Aguda
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