Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 15 de 15
Filter
4.
Int Arch Occup Environ Health ; 94(3): 495-501, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33156391

ABSTRACT

PURPOSE: The present work aims to study the effects of whole body vibration (WBV) on bus fare collectors through the use of cognitive tests. It is of interest for all individuals working as bus fare collectors or any other activity where logic is of paramount importance and that is performed on a vibrating environment. METHODS: Laboratory simulations were performed in 24 volunteers employing a vibrating platform subjected to vertical vibration. The influence of WBV on cognition was assessed using the performance on a logic game. The frequencies used were 5 Hz and 30 Hz. The acceleration amplitude values were set up as 0.7 m/s2 and 0.2 m/s2. A daily commute was simulated, based on data of the public transport system in the city of Belo Horizonte. A vibration-free test was initially performed to serve as a basis for comparison. RESULTS: The data obtained in all situations were compared and statistically analyzed. At 5 Hz, variation only shows significant after 5 min of vibration ceased as if the residual effect had passed after 5 min of rest. The gender variable was not significant. However, the older the volunteer, the worse the performance. Regarding 30 Hz frequency, the hypotheses did not meet the condition of significance at 5% but showed an opposite tendency indicating, in this situation, a score increase. It is noticed that the female volunteers presented a better performance in relation to the male gender The residual effect lasts for less than 10 min for short exposure intervals, since the score of test 8, in 5 Hz and 30 Hz, show a reduction of performance. CONCLUSIONS: From the results, it was possible to conclude that the frequency of 5 Hz may be related to reduced performance for long exposure times while the 30 Hz frequency has positive effects on cognition as the exposure time increases. In fact, it is a tendency much more than a clear statistical finding. Regarding comfort, most reports related to the frequency of 5 Hz are linked to the sensation of discomfort and difficulty in focusing visually, whereas, for the frequency of 30 Hz, the reports indicate a feeling of muscular comfort and increased easiness of concentration.


Subject(s)
Cognition , Motor Vehicles , Occupational Exposure , Vibration , Brain , Female , Humans , Male , Mobile Applications , Neuropsychological Tests , Occupations
5.
Morphologie ; 104(347): 254-266, 2020 Dec.
Article in English | MEDLINE | ID: mdl-32972816

ABSTRACT

During the last century, there were no significant changes in the teaching methods of anatomy in universities, predominating expositive lectures, and anatomy laboratory activities. With the advent of new technologies, simulators, augmented reality, and virtual reality, new teaching possibilities have emerged that may provide assistance and, in some situations, replace traditional methods of teaching. In this narrative scope review we evaluate articles that compare traditional methods with virtual reality or augmented reality through a search on Cochrane library, MEDLINE, EMBASE, and LILACS databases, using the MeSH terms "Anatomy", "Virtual Reality", "Augmented Reality", "Video Games", "Education Medical, Undergraduate", "Teaching" and "Simulation Training". We concluded that virtual reality and augmented reality have a promising value for teaching anatomy in addition to a positive economic impact on universities.


Subject(s)
Anatomy , Augmented Reality , Education, Medical, Undergraduate , Learning , Virtual Reality , Anatomy/education , Educational Measurement
6.
Oncogene ; 34(10): 1270-9, 2015 Mar 05.
Article in English | MEDLINE | ID: mdl-24662834

ABSTRACT

Intratumoral heterogeneity (ITH) represents an obstacle for cancer diagnosis and treatment, but little is known about its functional role in cancer progression. The A Desintegrin And Metalloproteinase 23 (ADAM23) gene is epigenetically silenced in different types of tumors, and silencing is often associated with advanced disease and metastasis. Here, we show that invasive breast tumors exhibit significant ADAM23-ITH and that this heterogeneity is critical for tumor growth and metastasis. We demonstrate that while loss of ADAM23 expression enhances invasion, it causes a severe proliferative deficiency and is not itself sufficient to trigger metastasis. Rather, we observed that, in ADAM23-heterotypic environments, ADAM23-negative cells promote tumor growth and metastasis by enhancing the proliferation and invasion of adjacent A23-positive cells through the production of LGI4 (Leucine-rich Glioma Inactivated 4) and nitric oxide (NO). Ablation of LGI4 and NO in A23-negative cells significantly attenuates A23-positive cell proliferation and invasion. Our work denotes a driving role of ADAM23-ITH during disease progression, shifting the malignant phenotype from the cellular to the tissue level. Our findings also provide insights for therapeutic intervention, enforcing the need to ascertain ITH to improve cancer diagnosis and therapy.


Subject(s)
ADAM Proteins/metabolism , Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Extracellular Matrix Proteins/metabolism , Nitric Oxide/metabolism , ADAM Proteins/genetics , Breast Neoplasms/genetics , Cell Line, Tumor , Cell Proliferation , DNA Methylation , Epigenesis, Genetic , Extracellular Matrix Proteins/genetics , Female , Gene Silencing , Humans , Neoplasm Metastasis , Nerve Tissue Proteins , Tumor Burden , Tumor Microenvironment
7.
Int J Dermatol ; 45(7): 822-7, 2006 Jul.
Article in English | MEDLINE | ID: mdl-16863519

ABSTRACT

BACKGROUND: Modifications in social habits together with the increase of emigration have contributed not only to increased dermatophytoses but also to an altered etiology. During the last few years, Braga has suffered a radical change from a rural to a cosmopolitan life-style. METHODS: A statistical study of dermatophytoses and the etiology of their causative agents was performed by a retrospective survey carried out among patients of Hospital de São Marcos, Braga, Portugal, from 1983-2002. In this study, a total of 10,003 patients were analyzed. RESULTS: Over this period the frequency of dermatophytoses, as defined by the recovery of a dermatophyte in culture, was found to be 23.6%, whereas nondermatophytic infections accounted for 7.0%. Analysis of the clinical forms and the isolated fungi supports that the dermatophyte species have a predilection for certain body areas (P

Subject(s)
Dermatomycoses/epidemiology , Adolescent , Adult , Age Distribution , Aged , Aged, 80 and over , Child , Child, Preschool , Dermatomycoses/diagnosis , Dermatomycoses/microbiology , Female , Health Surveys , Humans , Infant , Male , Middle Aged , Portugal/epidemiology , Retrospective Studies , Sex Distribution
8.
Int J Biol Macromol ; 31(1-3): 1-8, 2002 Dec 20.
Article in English | MEDLINE | ID: mdl-12559421

ABSTRACT

Linking up the user-friendly and low-priced FTIR with the more sophisticated and high-priced 13C CP/MAS NMR spectroscopies, an improved method to determine the degree of acetylation (DA) of chitins and chitosans was outlined. The method was established for the most complex polymorphic form (alpha-chitin) and for the most problematic range of DA values (most acetylated samples) and can easily be extended to the other polymorphic forms (beta- and gamma-chitins) and to other ranges of DA values.


Subject(s)
Chitin/analogs & derivatives , Chitin/chemistry , Spectroscopy, Fourier Transform Infrared/methods , Acetylation , Animals , Chitosan , Crustacea , Magnetic Resonance Spectroscopy , Radar
9.
Int J Biol Macromol ; 28(5): 359-63, 2001 Jun 12.
Article in English | MEDLINE | ID: mdl-11325422

ABSTRACT

13C CP/MAS NMR spectroscopy has been shown to be a powerful tool to quantify the degree of acetylation of chitin and chitosan. In order to optimise the parameters which afford quantitative 13C cross-polarisation magic-angle spinning NMR spectra, a detailed relaxation study has been carried out on selected chitin and deacetylated chitin samples. A relaxation delay of 5 s and a contact time of 1 ms have been found to yield quantitative NMR spectra of samples with deacetylation degree values of 0.68 and 0.16. The measured spin-lattice relaxation times in the rotating frame, T(1rhoH), are in the range 6.4-8.9 ms for chitin and 4.3-7.3 ms for deacetylated chitin, while TCH values for both samples are very similar and range from 0.03 to 0.19 ms. Spin-counting experiments indicate that, within experimental error, all carbon is detected by NMR indicating that the samples studied contain no (or very few) paramagnetic centres.


Subject(s)
Brachyura/chemistry , Chitin/analysis , Chitin/chemistry , Nuclear Magnetic Resonance, Biomolecular , Acetylation , Animals , Carbon Isotopes , Electron Spin Resonance Spectroscopy
11.
Arq Bras Cardiol ; 75(3): 215-24, 2000 Sep.
Article in English, Portuguese | MEDLINE | ID: mdl-11018807

ABSTRACT

OBJECTIVE: To identify characteristics associated with complications during pregnancy and puerperium in patients with rheumatic mitral stenosis. METHODS: Forty-one pregnant women (forty-five pregnancies) with mitral stenosis, followed-up from 1991 to 1999 were retrospectively evaluated. PREDICTOR VARIABLES: the mitral valve area (MVA), measured by echocardiogram, and functional class (FC) before pregnancy (NYHA criteria). Maternal events: progression of heart failure, need for cardiac surgery or balloon mitral valvulotomy, death, and thromboembolism. Fetal/neonatal events: abortion, fetal or neonatal death, prematurity or low birth weight (<2,500 g), and extended stay in the nursery or hospitalization in newborn ICU. RESULTS: The mean +/- SD of age of the patients was 28.8+/-4.6 years. The eventful and uneventful patients were similar in age and percentage of first pregnancies. As compared with the level 1 MVA, the relative risk (RR) of maternal events was 5.5 (95% confidence interval (CI) =0.8-39.7) for level 2 MVA and 11.4 (95% CI=1.7-74.5) for level 3 MVA. The prepregnancy FC (FC > or = II and III versus I) was also associated with risk for maternal events (RR=2.7; 95% CI=1.4-5.3).MVA and FC were not importantly associated with these events, although a smaller frequency of fetal/neonatal events was observed in patients who had undergone balloon valvulotomy. CONCLUSION: In pregnant women with mitral stenosis, the MVA and the FC are strongly associated with maternal complications but are not associated with fetal/neonatal events. Balloon mitral valvulotomy could have contributed to reducing the risks of fetal/neonatal events in the more symptomatic patients who had to undergo this procedure during pregnancy.


Subject(s)
Mitral Valve Stenosis/physiopathology , Pregnancy Complications, Cardiovascular/physiopathology , Rheumatic Heart Disease/physiopathology , Adult , Confidence Intervals , Echocardiography , Female , Fetal Diseases/physiopathology , Humans , Mitral Valve Stenosis/complications , Parity , Pregnancy , Prognosis , Rheumatic Heart Disease/complications , Risk
12.
Spectrochim Acta A Mol Biomol Spectrosc ; 56(6): 1051-64, 2000 May.
Article in English | MEDLINE | ID: mdl-10845535

ABSTRACT

Results obtained for the isolated and liquid 3-amino-1-propanol by a concerted molecular orbital and vibrational spectroscopic approach are reported. The relative energies and both structural and vibrational data of the different conformers of the studied compound were calculated using the extended 6-31G* basis set both at the HF-SCF and MP2 ab initio levels of theory and the theoretical results used to interpret Raman and infrared experimental data. In the gaseous phase and for the molecule isolated in an Argon matrix, monomeric 3-amino-1-propanol exists as a mixture of conformers, the first and second lowest energy forms corresponding to conformers which exhibit an intramolecular OH-N hydrogen bond (forms I and II). On the other hand, in the pure liquid, where intermolecular H-bonding occurs, the monomeric unit within the aggregates assumes a conformation similar to that of the third most stable form found for the isolated molecule situation (form III), which is characterised by having a weak intramolecular NH-O bond. The experimental data obtained for the pure liquid also reveals the presence of monomeric form I in this phase, a result that is in consonance with the strongly stabilizing OH-N intramolecular hydrogen bond that is present in this conformer.


Subject(s)
Propanolamines/chemistry , Carbon Tetrachloride/chemistry , Molecular Conformation , Spectrophotometry, Infrared , Spectrum Analysis, Raman
13.
Arq Bras Cardiol ; 61(4): 213-6, 1993 Oct.
Article in Portuguese | MEDLINE | ID: mdl-8154999

ABSTRACT

PURPOSE: To present immediate results of percutaneous mitral valvuloplasty (PVM) with Inoue balloon for the treatment of mitral stenosis. METHODS: One hundred and twelve consecutive patients mean age 31.26 +/- 9.5 years, 82% females, the majority in functional class III/IV (69%) underwent percutaneous mitral valvuloplasty (PVM) with Inoue balloon. The procedure was undertaken by the transseptal technique. RESULTS: PMV achieved significant reduction in mean left atrial pressure pre 24.57 +/- 5.37 post 12.36 +/- 4.82, mitral gradient pre 15.31 +/- 4.28 post 3.48 +/- 2.09 and increased mitral valve area pre 0.88 +/- 0.12 post 2.0 +/- 0.28 (P < 0.001). An increase of at least 25% of the mitral valve area with a final result greater than 1.5 cm2 was obtained in 96% of the cases. Cardiac tamponade occurred in five cases (4.4%). In 4 a successful treatment was accomplished in the catheterization laboratory. Significant mitral regurgitation was seen in one case (0.9%) and there was one death (0.9%). CONCLUSION: The results of this series attest to the effectiveness of the PMV with Inoue balloon in selected cases of mitral stenosis.


Subject(s)
Balloon Occlusion , Catheterization , Mitral Valve Stenosis/therapy , Adolescent , Adult , Child , Female , Humans , Male , Middle Aged , Retrospective Studies , Treatment Outcome
15.
Am J Physiol ; 260(3 Pt 1): E471-6, 1991 Mar.
Article in English | MEDLINE | ID: mdl-2003601

ABSTRACT

Reductions in peak bone mass at skeletal maturity may increase the risk for the subsequent development of osteoporosis. Although changes in calcium intake can modify the rate of decline in bone density in the mature skeleton, longitudinal assessments of the effect of dietary calcium supplementation during skeletal growth on peak bone mass have not been done in humans or experimental animals. Thus quantitative computed tomography (QCT) was used to monitor changes in vertebral bone density at 6-wk intervals during growth from 8 wk of age until skeletal maturity at 35 wk in male New Zealand White rabbits maintained on diets containing 0.15% (low Ca), 0.45% (normal Ca), or 1.35% (high Ca) calcium. Serum parathyroid hormone (PTH) and calcitriol levels increased, and renal calcium excretion decreased in low Ca compared with normal Ca; in contrast, serum calcitriol levels decreased and renal calcium excretion increased from control values in high Ca. Vertebral bone density by QCT did not differ during growth between high Ca and normal Ca, and peak values at epiphyseal closure also did not differ in these two groups. Vertebral bone density was lower, however, throughout the study in low Ca, and peak values at epiphyseal closure remained below those in either normal Ca or high Ca. Quantitative bone histology revealed decreases in cortical thickness in the third lumbar vertebra in low Ca, whereas trabecular bone area did not differ among groups; there was no histological evidence of osteomalacia in low Ca. Thus dietary calcium restriction during growth reduces peak bone mass at skeletal maturity, but raising dietary calcium intake above normal levels does not increase peak bone mass in this experimental model.


Subject(s)
Bone Density/drug effects , Bone Development/drug effects , Calcium, Dietary/pharmacology , Animals , Bone and Bones/diagnostic imaging , Calcitriol/blood , Calcium/blood , Calcium/urine , Male , Parathyroid Hormone/blood , Rabbits , Tomography, X-Ray Computed
SELECTION OF CITATIONS
SEARCH DETAIL
...