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1.
Int Endod J ; 53(9): 1181-1191, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32496605

RESUMEN

AIM: To explore a set of inflammatory biomarkers obtained from dentinal fluid (DF) from patients with symptomatic irreversible pulpitis (IP), reversible pulpitis (RP) and normal pulp (NP). METHODOLOGY: A cross-sectional exploratory study was performed, recruiting 64 patients on the basis of their respective pulp condition. DF samples were obtained from all patients (23, from IP patients; 20, from RP patients; and 21, from NP patients). Quantification of biomarkers was performed using a Luminex® MAGPIX platform system and multiplex assay kits. The Kruskal-Wallis test was used for comparisons with regard to pulp state. A simple logistic regression model and the odds ratio (OR) with a 95% level of confidence (P = 0.05) were used to evaluate associations between biomarker levels and pulpal diagnosis. The performance discrimination of the biomarkers was evaluated through the construction of a receiver operating characteristic (ROC) curve by calculating the area under the curve (AUC) for IP versus RP after logistic regression modelling. Youden criteria were used to establish cut-off points for biomarkers alone with AUC > 70 and P-value < 0.05, or estimated probabilities from the multivariable logistic model. RESULTS: The biomarkers that had significantly higher values in participants with IP versus RP were IL-1α, VEGF-α and FGF acid (P < 0.05). FGF acid (OR: 12.62; P = 0.0085; CI 95% 1.91-83.29) and VEGF-α (OR: 2.61; P = 0.0252; CI 95% 1.13-6.03) were associated with pulp diagnoses of IP versus RP. The AUC-ROC curve for FGF acid was 0.79. The model containing FGF acid, IL-1α, IL-6 and TIMP-1 had an AUC-ROC of 0.92 for IP versus RP with a significant difference from the FGF acid ROC curve (P = 0.0231). CONCLUSIONS: Dentinal fluid could be used to assay pulpal mediators in the molecular diagnosis of pulpitis. Despite the limitation of the clinical diagnostics used in the present study, it was possible to detect a difference between irreversible symptomatic pulpitis and reversible pulpitis associated with the following combined biomarkers: FGF acid + IL-6 + IL-1α, +TIMP-1.


Asunto(s)
Pulpitis , Biomarcadores , Estudios Transversales , Pulpa Dental , Líquido de la Dentina , Humanos , Patología Molecular
2.
Proc Biol Sci ; 285(1891)2018 11 14.
Artículo en Inglés | MEDLINE | ID: mdl-30429300

RESUMEN

In group-living species, social stability is an important trait associated with the evolution of complex behaviours such as cooperation. While the drivers of stability in small groups are relatively well studied, little is known about the potential impacts of unstable states on animal societies. Temporary changes in group composition, such as a social group splitting and recombining (i.e. a disturbance event), can result in individuals having to re-establish their social relationships, thus taking time away from other tasks such as foraging or vigilance. Here, we experimentally split socially stable groups of captive zebra finches (Taeniopygia guttata), and quantified the effects of repeated disturbance events on (1) group foraging efficiency, and (2) co-feeding associations when subgroups were recombined. We found that the efficiency of groups to deplete a rich, but ephemeral, resource patch decreased after just a single short disturbance event. Automated tracking of individuals showed that repeated disturbances reduced efficiency by causing social relationships to become more differentiated and weaker, resulting in fewer individuals simultaneously accessing the patch. Our experiment highlights how short-term disturbances can severely disrupt social structure and group functionality, revealing potential costs associated with group instability that can have consequences for the evolution of animal societies.


Asunto(s)
Conducta Alimentaria , Conducta Social , Pájaros Cantores/fisiología , Animales , Femenino , Pinzones/fisiología , Masculino
3.
J Periodontal Res ; 48(3): 302-7, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23035752

RESUMEN

AIM(S): To explore the relationship between biomarkers of systemic inflammation in plasma and gingival crevicular fluid in early pregnancy and the subsequent development of pre-eclampsia in patients with periodontitis. MATERIALS AND METHODS: A case-control study was performed. From a cohort composed of 126 pregnant women, 43 normotensive healthy pregnant women were randomly selected, and 11 cases of preeclampsia were identified. Plasmatic and gingival crevicular fluid (GCF) samples were collected in early pregnancy (11-14 wk gestation). The levels of interleukin-6 (IL-6) and tumour necrosis factor-α (TNF-α) were measured in the plasma and GCF samples, whereas the level of C-reactive protein (CRP) was measured in plasma samples. Biomarkers were determined by ELISA assays. The data were analysed using descriptive statistics, and the association between variables was estimated through logistic regression models. RESULTS: There was observed an association between pre-eclampsia and plasmatic levels of CRP (OR: 1.07; p = 0.003). Additionally, pre-eclampsia also was associated with IL-6 levels in GCF samples in early pregnancy (OR: 1.05; p = 0.039). A multiple logistic regression model suggests that increased levels of IL-6 in GCF (OR = 1.06; p = 0.02; CI 95% 1.007-1.117) in early pregnancy increase the risk of developing pre-eclampsia. CONCLUSION(S): Pregnant women with periodontitis who later development pre-eclampsia, shows increased levels of IL-6 in GCF and CRP in plasma during early pregnancy. Periodontal disease could contribute to systemic inflammation in early pregnancy via a local increase of IL-6 and the systemic elevation of CRP. Therefore, both inflammatory markers could be involved in the relationship between periodontal disease and pre-eclampsia.


Asunto(s)
Proteína C-Reactiva/metabolismo , Líquido del Surco Gingival/química , Interleucina-6/metabolismo , Periodontitis/complicaciones , Preeclampsia/etiología , Primer Trimestre del Embarazo/metabolismo , Adulto , Proteína C-Reactiva/análisis , Estudios de Casos y Controles , Femenino , Humanos , Interleucina-6/análisis , Interleucina-6/sangre , Modelos Logísticos , Periodontitis/sangre , Periodontitis/metabolismo , Preeclampsia/sangre , Preeclampsia/metabolismo , Embarazo , Primer Trimestre del Embarazo/sangre , Factor de Necrosis Tumoral alfa/análisis , Factor de Necrosis Tumoral alfa/sangre , Factor de Necrosis Tumoral alfa/metabolismo , Adulto Joven
4.
J Periodontal Res ; 48(6): 802-9, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23711357

RESUMEN

AIM(S): To explore the associations between the presence of periodontal pathogens and the expression of toll-like receptors (TLR-2 and TLR-4) in the placental tissue of patients with hypertensive disorders compared to the placentas of healthy normotensive patients. MATERIAL AND METHODS: A case-control study was performed. From a cohort composed of 126 pregnant women, 33 normotensive healthy pregnant women were randomly selected, and 25 cases of patients with hypertensive disorders of pregnancy, including gestational hypertension and pre-eclampsia, were selected. Placental biopsy was obtained after aseptic placental collection at the time of delivery. All of the samples were processed and analysed for the detection of Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum, Treponema denticola and Tannerella forsythia using the polymerase chain reaction (PCR) technique. Determination of the expressions of TLR-2 and TLR-4 was performed in samples of total purified protein isolated from placental tissues and analysed by ELISA. The data were assessed using descriptive statistics. The associations among variables were estimated through multiple logistic regression models and the Mann-Whitney test to evaluate the differences between the two groups. RESULTS: A significant increase was observed in the expression of TLR-2 in the placentas of patients with hypertensive disorders (p = 0.04). Additionally, the multiple logistic regression models demonstrated an association between the presence of T. denticola and P. gingivalis in placental tissues and hypertensive disorders (OR: 9.39, p = 0.001, CI 95% 2.39-36.88 and OR: 7.59, p = 0.019, CI 95% 1.39-41.51, respectively). CONCLUSIONS: In the present study, pregnant women with periodontal disease presented an association in the placental tissue between the presence of T. denticola and P. gingivalis and hypertensive disorders. Additionally, increased expression of TLR-2 was observed. However, further studies are required to determine the specific roles of periodontal pathogens and TLRs in the placental tissue of patients with pregnancy-related hypertensive disorders.


Asunto(s)
Hipertensión Inducida en el Embarazo/microbiología , Placenta/inmunología , Porphyromonas gingivalis/aislamiento & purificación , Receptor Toll-Like 2/análisis , Treponema denticola/aislamiento & purificación , Adulto , Aggregatibacter actinomycetemcomitans/inmunología , Aggregatibacter actinomycetemcomitans/aislamiento & purificación , Bacteroides/inmunología , Bacteroides/aislamiento & purificación , Estudios de Casos y Controles , Estudios de Cohortes , Femenino , Fusobacterium nucleatum/inmunología , Fusobacterium nucleatum/aislamiento & purificación , Gingivitis/inmunología , Gingivitis/microbiología , Humanos , Hipertensión Inducida en el Embarazo/inmunología , Pérdida de la Inserción Periodontal/inmunología , Pérdida de la Inserción Periodontal/microbiología , Índice Periodontal , Bolsa Periodontal/inmunología , Bolsa Periodontal/microbiología , Periodontitis/inmunología , Periodontitis/microbiología , Placenta/microbiología , Porphyromonas gingivalis/inmunología , Preeclampsia/inmunología , Preeclampsia/microbiología , Embarazo , Receptor Toll-Like 4/análisis , Treponema denticola/inmunología
5.
Toxicol In Vitro ; 58: 224-229, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30946969

RESUMEN

Perfluorodecanoic acid (PFDA) is a synthetic perfluorinated compound, which has been reported to exert adverse effects on somatic cells. However, its effects on germ cells have not been studied to date. The aim of the present study was to analyze the effects of PFDA on the viability, intracellular calcium levels and gap junction intercellular communication (GJIC) during porcine oocyte maturation in vitro. PFDA negatively impacted oocyte viability (medium lethal concentration, LC50 = 7.8 µM) and maturation (medium inhibition of maturation, IM50 = 3.8 µM). Oocytes exposed to 3.8 µM PFDA showed higher levels of intracellular calcium relative to control oocytes. In addition, GJIC among the cumulus cells and the oocyte was disrupted. The effects of PFDA on oocyte calcium homeostasis and intercellular communication seem to be responsible for the inhibition of oocyte maturation and oocyte death. In addition, since the deleterious effects of PFDA on oocyte viability, maturation and GJIC are significantly stronger than the previously reported effects of another widely used perfluorinated compound (Perfluorooctane sulfonate) in the same model, the use of PFDA in consumer products is questioned.


Asunto(s)
Ácidos Decanoicos/toxicidad , Fluorocarburos/toxicidad , Oocitos/efectos de los fármacos , Animales , Calcio/metabolismo , Comunicación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Células del Cúmulo/efectos de los fármacos , Células del Cúmulo/fisiología , Femenino , Uniones Comunicantes/efectos de los fármacos , Oocitos/fisiología , Porcinos
6.
Primates ; 57(1): 17-28, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26386711

RESUMEN

Relationships between conspecifics are influenced by both ecological factors and the social organization they live in. Systematic variation of both--consistent with predictions derived from socioecology models--is well documented, but there is considerable variation within species and populations that is poorly understood. The mountain gorilla (Gorilla beringei) is unusual because, despite possessing morphology associated with male contest competition (e.g., extreme sexual dimorphism), they are regularly observed in both single-male and multimale groups. Both male-female and male-infant bonds are strong because males provide protection against infanticide and/or predation. Risk of these threats varies with social structure, which may influence the strength of social relationships among group members (including females and offspring, if females with lower infant mortality risk are less protective of infants). Here, we investigate the relationship between group structure and the strength of proximity relationships between males and females, males and infants, and females and offspring. Data come from 10 social groups containing 1-7 adult males, monitored by the Dian Fossey Gorilla Fund's Karisoke Research Center in Volcanoes National Park, Rwanda. After controlling for group size and infant age, association strength was similar for male-female pairs across group types with both dominant and nondominant males, but male-infant relationships were strongest in single-male groups where paternity certainty was high and animals had fewer social partners to choose from. The male:female and male:infant ratios better predicted both male-female and male-infant associations than the absolute number of males, females, or infants did. The fewer the number of males per female or infant, the more both pair types associated. Dominant males in groups containing fewer males had higher eigenvector centrality (a measure of importance in a social network) than dominant males in groups with more males. Results indicate that nondominant males are an important influence on relationships between dominant males and females/infants despite their peripheral social positions, and that relationships between males and infants must be considered an important foundation of gorilla social structure.


Asunto(s)
Gorilla gorilla/fisiología , Conducta Social , Animales , Femenino , Estructura de Grupo , Masculino , Rwanda
7.
Placenta ; 48 Suppl 1: S7-S11, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-26733365

RESUMEN

Workshops are an integral component of the annual International Federation of Placenta Association (IFPA) meeting, allowing for networking and focused discussion related to specialized topics on the placenta. At the 2015 IFPA meeting (Brisbane, Australia) twelve themed workshops were held, three of which are summarized in this report. These workshops focused on various aspects of placental function, particularly in cases of placenta-mediated disease. Collectively, these inter-connected workshops highlighted the role of the placenta in fetal programming, the use of various biomarkers to monitor placental function across pregnancy, and the clinical impact of novel diagnostic and surveillance modalities in instances of late onset fetal growth restriction (FGR).


Asunto(s)
Desarrollo Fetal/fisiología , Placenta/fisiología , Placentación/fisiología , Complicaciones del Embarazo/fisiopatología , Biomarcadores , Femenino , Humanos , Embarazo
8.
Invest Ophthalmol Vis Sci ; 34(7): 2341-7, 1993 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8505215

RESUMEN

PURPOSE: To investigate why the central portion of the visual field is normally the optimal region for pattern recognition. METHOD: The study uses a reading paradigm in which the text can only be seen with rod vision. Reading rates were measured as the text was positioned in different parts of the visual field. RESULTS: Observers obtained the highest reading rates when rod-generated images were viewed at or near the fovea. CONCLUSION: The superiority of the central field for reading is neither linked to some exclusive property of the cone visual system, nor is it primarily related to visual sensitivity or spatiotemporal resolution. The superiority of reading in the central field is associated with some aspect of the visual cortical processes.


Asunto(s)
Reconocimiento Visual de Modelos/fisiología , Células Fotorreceptoras/fisiología , Lectura , Adulto , Femenino , Humanos , Luz , Masculino , Umbral Sensorial , Campos Visuales/fisiología
9.
Invest Ophthalmol Vis Sci ; 30(5): 806-12, 1989 May.
Artículo en Inglés | MEDLINE | ID: mdl-2785978

RESUMEN

ERG oscillatory potentials (OPs) were recorded from obligate carriers of CSNB and from age-matched normal subjects. The OPs were recorded under four stimulus conditions and were analyzed in the time and frequency domains. The results, first of all, provide confirmation of the previous report that the OP amplitude is reduced in carriers. Second, the results show that, of four stimulus conditions examined, the best condition for discriminating the carriers and normal subjects was when the flash was blue and the eye was dark-adapted. Third, the results show that, in the frequency domain, optimal discrimination occurs when examining the power content of the OP at a center frequency of about 130 Hz using a 70 Hz bandwidth window. In the time domain, optimal discrimination occurs when examining the amplitude of the third peak of the response.


Asunto(s)
Heterocigoto , Ceguera Nocturna/congénito , Retina/fisiopatología , Cromosoma X , Electrorretinografía , Estudios de Evaluación como Asunto , Femenino , Tamización de Portadores Genéticos/métodos , Humanos , Ceguera Nocturna/fisiopatología , Valores de Referencia
10.
Vision Res ; 34(6): 751-62, 1994 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8160391

RESUMEN

Detection contours were measured in L and M cone contrast coordinates for foveal flashes of 200 msec duration and 2.3, 5, 10 and 15 min arc diameter on a bright yellow field. The test flash consisted of simultaneous incremental and decremental red and green lights in various amplitude ratios. At all sizes, the most sensitive detection mechanism was not a luminance mechanism, but rather a red-green mechanism that responds to the linear difference of equally weighted L and M cone contrasts, and signals red or green sensations at the detection threshold. Both temporal and spatial integration were greater for red-green detection than luminance detection. A coincident, subthreshold, yellow flash (a luminance pedestal) did not affect the threshold of the red-green mechanism. Such a pedestal is a sum of equal L and M cone contrast--it represents a vector parallel to the red-green detection contour and thus is expected not to stimulate directly the red-green mechanism. When suprathreshold, the coincident pedestal facilitated chromatic detection by approximately 2x at all tested sizes; intense pedestals did not mask chromatic detection. This insensitivity to intense luminance pedestals further indicates that the red-green mechanism has fixed spectral tuning with balanced opponent L and M contrast inputs. This view of fixed spectral weights contrasts with the "variable tuning hypothesis", which postulates that the weights change with spatial-temporal variations in the test stimulus.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Percepción de Color/fisiología , Sensibilidad de Contraste/fisiología , Fóvea Central/fisiología , Humanos , Células Fotorreceptoras Retinianas Conos/fisiología , Umbral Sensorial/fisiología , Espectrofotometría
11.
Vision Res ; 35(22): 3103-18, 1995 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8533346

RESUMEN

Recent physiological evidence suggests that cones do not light adapt at low light levels. To assess whether adaptation is cone-selective at low light levels, the red-green detection mechanism was isolated. Thresholds were measured with a large test flash, which stimulated the L and M cones in different fixed amplitude ratios, on different colored adapting fields. Thresholds were plotted in L and M cone contrast coordinates. The red-green mechanism responded to an equally-weighted difference of L and M cone contrast on each colored field, demonstrating equivalent, Weberian adaptation of the L and M cone signals. The L and M cone signals independently adapted for illuminance levels as low as 60 effective trolands (e.g. M-cone trolands). Since this adaptation is entirely selective to cone type, it suggests that the cones themselves light-adapt. The red-green detection contour on reddish fields was displaced further out from the origin of the cone contrast coordinates, revealing an additional sensitivity loss at a subsequent, spectrally-opponent site. This second-site effect may arise from a net "red" or "green" signal that represents the degree to which the L and M cones are differently hyperpolarized by the steady, colored adapting field. Such differential hyperpolarization is compatible with equivalent, Weberian adaptation of the L and M cones.


Asunto(s)
Adaptación Ocular/fisiología , Percepción de Color/fisiología , Células Fotorreceptoras Retinianas Conos/fisiología , Humanos , Iluminación , Umbral Sensorial/fisiología , Espectrofotometría
12.
Vision Res ; 39(12): 2099-112, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10343793

RESUMEN

Detection thresholds plotted in the L and M cone-contrast plane have shown that there are two primary detection mechanisms, a red-green hue mechanism and a light-dark luminance mechanism. However, previous masking results suggest there may be additional mechanisms, responsive to combined features like bright and red or dark and green. We measured detection thresholds for a 1.2 c deg-1 sine-wave grating in the presence of a spatially matched mask grating which was either stationary, dynamically jittered or flickered. The stimuli could be set to any direction in the L,M plane. The appearance of selectivity for combined hue and luminance arose only in conditions where adding the test to the mask modified the spatial phase offset between the luminance and red-green stimulus components. Sensitivity was very high for detecting this spatial phase offset. When this extra cue was eliminated, masking contours in the L,M plane could be largely described by the classical red-green and luminance mechanisms.


Asunto(s)
Percepción de Color/fisiología , Enmascaramiento Perceptual/fisiología , Sensibilidad de Contraste , Humanos , Iluminación , Reconocimiento Visual de Modelos/fisiología , Psicofísica , Rotación , Umbral Sensorial/fisiología
13.
Vision Res ; 39(18): 3011-23, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10664800

RESUMEN

The red-green (RG) detection mechanism was revealed by measuring threshold detection contours in the L and M cone contrast plane for sine-wave test gratings of 0.8-6 c deg-1 on bright adapting fields of yellow or red. The slope of the RG detection contours was unity, indicating that the L and M contrast signals contribute equally (with opposite signs) on both the yellow and the red fields: this reflects first-site, cone-selective adaptation. Second-site adaptation, which may reflect saturation at a color-opponent site, was evidenced by the RG detection contours being further out from the origin of the cone contrast plane on the red field than on the yellow field. Second-site adaptation was strong (3-fold) for low spatial frequency test gratings but greatly diminished by 6 c deg-1. The disappearance of second-site adaptation with increasing spatial frequency can be explained by spatial frequency channels. The most sensitive detectors may comprise a low spatial frequency channel which is susceptible to masking by the chromatic, spatial DC component of the red field. The 6 c deg-1 patterns may be detected by a less sensitive, higher frequency channel which is less affected by the uniform red field. The RG spatial frequency channels likely arise in the cortex, implicating a partially central site for the second-site effect.


Asunto(s)
Adaptación Fisiológica/fisiología , Percepción de Color/fisiología , Percepción Visual/fisiología , Sensibilidad de Contraste/fisiología , Discriminación en Psicología/fisiología , Humanos , Umbral Sensorial/fisiología , Percepción Espacial/fisiología
14.
Vision Res ; 38(6): 795-812, 1998 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9624431

RESUMEN

Contrast thresholds were measured for discriminating left vs right motion of a vertical, 1 c/deg luminance grating lasting for one cycle of motion. This test was presented on a 1 c/deg stationary grating (pedestal) of twice-threshold, flashed for the duration of the test motion. Lu and Sperling [(1995). Vision Research, 35, 2697-2722] argue that the visual system detects the underlying, first-order motion of the test and is immune to the presence of the stationary pedestal (and the 'feature wobble' which it induces). On the contrary, we observe that the stationary pedestal has large effects on motion detection at 7 and 15 Hz, and smaller effects at 0.9-3.7 Hz, evidenced by a spatial phase dependency between the stationary pedestal and moving test. At 15 Hz the motion threshold drops as much as five-fold, with the stationary pedestal in the optimal spatial phase (i.e., pedestal and test spatially in phase at middle of motion), and the perceived direction of the test motion reverses with the pedestal in the opposite phase. Phase dependency was also explored using a very brief (approximately 1 msec) static pedestal presented with the moving test. The pedestal of Lu and Sperling (flashed for the duration of the test) has a broad spectrum of left and right moving components which interact with the moving test. The pedestal effects can be explained by the visual system's much higher sensitivity to the difference of the contrast of right vs left moving components than to either component alone.


Asunto(s)
Percepción de Movimiento/fisiología , Reconocimiento Visual de Modelos/fisiología , Sensibilidad de Contraste/fisiología , Discriminación en Psicología , Humanos , Luz , Masculino , Matemática , Psicometría , Umbral Sensorial/fisiología
15.
Vision Res ; 38(6): 813-26, 1998 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9624432

RESUMEN

Previous work shows that the red-green (RG) detection mechanism is highly sensitive, responding to equal and opposite long-wave (L) and middle-wave (M) cone contrast signals. This mechanism mediates red-green hue judgements under many conditions. We show that the RG detection mechanism also receives a weak input from the short-wave (S) cones that supports the L signal and equally opposes M. This was demonstrated with a pedestal paradigm, in which weak S cone flicker facilitates discrimination and detection of red-green flicker. Also, a near-threshold +S cone flash facilitates detection of red flashes and inhibits green flashes, and a near-threshold -S cone flash facilitates detection of green flashes and inhibits red flashes. The S contrast weight in RG is small relative to the L and M contrast weights. However, a comparison of our results with other studies suggests that the strength of the absolute S cone contrast contribution to the RG detection mechanism is 1/4 to 1/3 the strength of the S contribution to the blue-yellow (BY) detection mechanism. Thus, the S weight in RG is a significant fraction of the S weight in BY. This has important implications for the 'cardinal' color mechanisms, for it predicts that for detection or discrimination, the mechanisms limiting performance do not lie on orthogonal M-L and S axes within the equiluminant color plane.


Asunto(s)
Percepción de Color/fisiología , Células Fotorreceptoras Retinianas Conos/fisiología , Umbral Diferencial , Fusión de Flicker , Humanos , Masculino , Matemática , Psicometría
16.
Arch Med Res ; 29(1): 51-5, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9556923

RESUMEN

BACKGROUND: The objective of this study was to determine levels of epidermal growth factor (EGF) and gastrin (GA) in saliva, serum, and urine in scleroderma (Scl) and CREST syndrome. METHODS: EGF and GA levels were measured by radioimmunoassay in saliva, serum and urine in 10 patients (51 years, median; range, 35-66 years); 9 females and 1 male with Scl, 3 females with CREST syndrome, and 18 age- and sex-matched controls, 17 females and 1 male free of any systemic inflammatory disease. RESULTS: In serum, the EGF was lower in Scl/CREST than controls (p = 0.02), while GA serum concentrations were higher in Scl/CREST (p = 0.02). In urine, EGF in Scl/CREST was slightly lower than controls (p = NS) and GA concentrations were higher than controls (p = 0.03). In saliva, the EGF levels in Scl/CREST were also slightly lower than controls (p = NS), while GA concentrations in both Scl/CREST and controls were not different (p = NS). CONCLUSIONS: Low concentrations of EGF in serum probably play a role in the pathogenesis of Scl/CREST. GA concentration can be increased as a consequence of the low levels of EGF because of the structural homology of this peptide with urogastrone, a GA inhibitor factor.


Asunto(s)
Síndrome CREST/metabolismo , Factor de Crecimiento Epidérmico/metabolismo , Gastrinas/metabolismo , Adulto , Anciano , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad
17.
Disabil Rehabil ; 22(13-14): 633-7, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11052213

RESUMEN

PURPOSE: The purpose of this study was to report normative values of the amplitude of joint wrist motions and grip strength for older age groups. METHOD: Volunteers. (N = 147) were divided into four age groups, 60-69, 70-79, 80-89 and 90+ years, with a total of 62 men and 85 women. Maximum range motion values were obtained for wrist flexion, extension and ulnar deviation. In addition, grip strength measures were obtained for each participant. RESULTS: In general, the strength and ROM values for the oldest participants in this study were lower than those of the younger age group (age 60 to 69) and significantly lower than those published for subjects between 25 and 54 years of age. Furthermore, across all age groups males were significantly stronger than females. However, females tended to have greater ROM than males, particularly for wrist extension and ulnar deviations. Joint ROM and grip strength declined significantly with age for both males and females. Comparisons with published data for younger subjects (age 25-35) indicate that a 60-69 year old male, will on average experience a decline in wrist flexion, extension and ulnar deviation of 12%, 41%, and 22% respectively. By age 90, an individual may be expected to have ROM values that are only approximately 60% of an average 30 year old individual. CONCLUSION: The results suggest that the ageing population (particularly men) may face greater difficulty using an input device such as a mouse that relies on motions of the wrist. In addition, the reduced ROM of the wrist may put the elderly at greater risk of developing cumulative trauma disorders. The implications of these findings for the design of input devices are discussed.


Asunto(s)
Envejecimiento/fisiología , Computadores , Rango del Movimiento Articular/fisiología , Muñeca/fisiología , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Diseño de Equipo , Femenino , Evaluación Geriátrica , Fuerza de la Mano , Humanos , Masculino , Persona de Mediana Edad , Distribución por Sexo
18.
Adv Perit Dial ; 12: 302-6, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8865924

RESUMEN

Malnutrition is often present on continuous ambulatory peritoneal dialysis (CAPD), and contributes to morbidity and mortality. Diabetics (DM) have an increased risk for developing malnutrition. Our purpose was to assess the nutritional status (NS) of our CAPD population, to define NS differences between DM and nondiabetics (NoDM), and to identify NS-related factors. Patients were subjected to a nutritional assessment, which included a 24-hour dietary recall and a nutritional scoring system including anthropometric, biochemical, and subjective evaluation, and that classifies patients as: normal, and mildly, moderately, and severely malnourished. We studied 90 patients: 35 DM and 55 NoDM. In our whole population we observed a high frequency of malnutrition: NS was normal in 18%, and 20% had mild, 24% had moderate, and 38% had severe malnutrition. Ninety-one percent of DM and 76% of NoDM showed some degree of malnutrition. DM patients had significantly higher levels of malnutrition (p = 0.02), were significantly older, had more body fat, and spent less time on dialysis. There were 37 males and 53 females. Sex distribution was similar between DM and NoDM. Seventy-six percent of males and 86% of females had malnutrition. Moderate and severe malnourishment were more frequent in females. DM and female sex were the strongest predictors for moderate and severe malnutrition.


Asunto(s)
Nefropatías Diabéticas/epidemiología , Fallo Renal Crónico/epidemiología , Diálisis Peritoneal Ambulatoria Continua , Desnutrición Proteico-Calórica/epidemiología , Adulto , Anciano , Antropometría , Colesterol/sangre , Estudios de Cohortes , Estudios Transversales , Nefropatías Diabéticas/sangre , Nefropatías Diabéticas/dietoterapia , Proteínas en la Dieta/administración & dosificación , Femenino , Humanos , Incidencia , Fallo Renal Crónico/sangre , Fallo Renal Crónico/dietoterapia , Masculino , México/epidemiología , Persona de Mediana Edad , Necesidades Nutricionales , Desnutrición Proteico-Calórica/sangre , Desnutrición Proteico-Calórica/dietoterapia
20.
Accid Anal Prev ; 72: 287-95, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25089769

RESUMEN

Research indicates that using a cell phone to talk or text while maneuvering a vehicle impairs driving performance. However, few published studies directly compare the distracting effects of texting using a hands-free (i.e., speech-based interface) versus handheld cell phone, which is an important issue for legislation, automotive interface design and driving safety training. This study compared the effect of speech-based versus handheld text entries on simulated driving performance by asking participants to perform a car following task while controlling the duration of a secondary text-entry task. Results showed that both speech-based and handheld text entries impaired driving performance relative to the drive-only condition by causing more variation in speed and lane position. Handheld text entry also increased the brake response time and increased variation in headway distance. Text entry using a speech-based cell phone was less detrimental to driving performance than handheld text entry. Nevertheless, the speech-based text entry task still significantly impaired driving compared to the drive-only condition. These results suggest that speech-based text entry disrupts driving, but reduces the level of performance interference compared to text entry with a handheld device. In addition, the difference in the distraction effect caused by speech-based and handheld text entry is not simply due to the difference in task duration.


Asunto(s)
Atención , Conducción de Automóvil , Simulación por Computador , Desempeño Psicomotor , Software de Reconocimiento del Habla , Envío de Mensajes de Texto , Interfaz Usuario-Computador , Accidentes de Tránsito , Adolescente , Adulto , Teléfono Celular , Femenino , Humanos , Masculino , Tiempo de Reacción , Adulto Joven
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