RESUMEN
Fatigue in forearm muscles may be critical for motorcycle riders in relation to performance and forearm disorders. Force-time course parameters were examined to better characterize the reduction in the maximal force generating capacity (MVC) during an intermittent fatigue protocol (IFP) specifically designed for motorcycle riders. Also, a mathematical force fatigue model is proposed. Forty motorcyclists (aged 27.6 ± 6.8 years) performed an IFP that simulated the braking gesture and posture of a rider. Fatigue was confirmed by a 40% decrement of the normalized MVC in comparison with basal value. Contraction time increased in comparison with basal condition (P ≤ 0.034). Relaxation kinetics presented two phases: (a) a pre-fatigue phase where half relaxation time (HRTraw ) and normalized (HRTnor ) decreased (P ≤ 0.013) while relaxation rate (RRraw ) remained unchanged; and (b) a fatiguing phase where HRTraw , HRTnor increased and RRraw decreased (P ≤ 0.047). Normalized RRraw (RRnor ) declined progressively (P ≤ 0.016). The proposed nonlinear force fatigue model confirmed a satisfactory adjustment (R(2) = 0.977 ± 0.018). This mathematical expression derived three patterns of force fatigue: three-phase, exponential and linear, representing 70%, 13%, and 17% of the participants, respectively. Overall, these results provided further support to force fatigue theoretical and applied proposals.
Asunto(s)
Fuerza de la Mano/fisiología , Contracción Isométrica/fisiología , Motocicletas , Contracción Muscular/fisiología , Fatiga Muscular/fisiología , Debilidad Muscular/fisiopatología , Músculo Esquelético/fisiología , Adulto , Electromiografía , Antebrazo , Humanos , Masculino , Modelos Teóricos , Adulto JovenRESUMEN
OBJECTIVES: To determine the incidence of headache after lumbar puncture, we prospectively studied 270 patients who underwent intradural anesthesia for programmed urologic, traumatologic, general, and gynaecologic surgery. PATIENTS AND METHODS: The mean age of the patients was 55.6 +/- 16.9 years. There were significant differences between the age of women (54.8 +/- 15.5 years) and men (56.4 +/- 18.4 years). Intradural anesthesia was performed with a Becton-Dickinson 26G needle with a Quincke tip. Patients were randomly divided into two groups according to that puncture was directed parallel (group 1) or perpendicular (group 2) to the dura-mater fibers. When the spinal liquid dripped through the needle, 2 ml of a 0.75% (15 mg) solution of bupivacaine and 0.2 ml of a 50% (100 mg) solution of glucose were injected. No special measures were undertaken during the postoperative phase. The incidence of headache was analyzed 72 hours after puncture. RESULTS: One patient of group 1 (0.66%) and 6 patients of group 2 (5%) presented headache. This difference was not statistically significant. Differences between the incidence of headache in women (4.05%) and in men (2.15%) were also not significant.
Asunto(s)
Anestesia Raquidea/métodos , Cefalea/epidemiología , Agujas , Punciones/métodos , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Femenino , Cefalea/etiología , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Estudios ProspectivosRESUMEN
Motorcycle races' long duration justify the study of forearm muscles fatigue, especially knowing the frequently associated forearm discomfort pathology. Moreover, while continuous fatigue protocols yield unequivocal results, EMG outcomes from an intermittent protocol are quite controversial. This study examined the forearm muscle fatigue patterns produced during these two protocols, comparing riders with a control group, and relating maximal voluntary contraction with EMG parameters (amplitude - NRMS and median frequency - NMF) of both protocols to the forearm discomfort among motorcycle riders. Twenty riders and 39 controls performed in separate days both protocols simulating the braking gesture and posture of a rider. EMG of flexor digitorum superficialis (FS) and carpi radialis (CR) were monitored. CR revealed more differences among protocols and groups compared to FS. The greater CR activation in riders could be interpreted as a neuromotor strategy to improve braking precision. When FS fatigue increased, the control group progressively shift toward a bigger CR activation, adopting an intermuscular activation pattern closer to riders. Despite the absence of NMF decrement throughout the intermittent protocol, which suggest that we should have shorten the recovery times from the actual 1 min, the superior number of rounds performed by the riders proved that this protocol discriminates better riders against controls and is more related to forearm discomfort.
Asunto(s)
Electromiografía/métodos , Antebrazo/fisiología , Motocicletas , Contracción Muscular/fisiología , Fatiga Muscular/fisiología , Músculo Esquelético/fisiología , Esfuerzo Físico/fisiología , Adulto , Humanos , MasculinoRESUMEN
PURPOSE: Our purpose was to investigate the role of the insemination technique used in an artificial insemination program with donor sperm (AID) in multiple pregnancy rates. METHODS: We carried out a retrospective nonrandom analysis of 300 pregnancies corresponding to 300 cycles in women from our Artificial Insemination Donor Sperm Program. All cycles were stimulated with gonadotropins. Single and multiple pregnancy cycles and intracervical and intrauterine pregnant cycles were compared. RESULTS: Intracervical insemination was performed in 173 cycles (58%), and intrauterine insemination in 127 (42%). Two hundred twenty-three pregnancies were single (74%), and 77 multiple (26%). In multiple pregnancy cycles, initial dose and mean total daily dose of gonadotropins, plasma estradiol levels, and number of follicles > or = 14 mm were significantly higher compared to those in single pregnancy cycles. Multiple pregnancy rte was significantly higher among pregnancies after intrauterine insemination (32%) than after intracervical insemination (21%). CONCLUSIONS: The intrauterine technique of insemination in AID-stimulated cycles with gonadotropins is related to multiple pregnancy risk.
Asunto(s)
Inseminación Artificial/métodos , Embarazo Múltiple , Adulto , Femenino , Hormona Folículo Estimulante , Humanos , Menotropinas , Embarazo , Estudios Retrospectivos , Factores de Riesgo , Donantes de TejidosRESUMEN
Implantation failure rates after in-vitro fertilization (IVF) can be reduced in the IVF laboratory using two different techniques: assisted hatching and embryo co-culture on monolayer feeder cells. A review of the different methodologies and the results gained using these techniques is reported. Preliminary results obtained in the Reproductive Medicine Service of the Institut Universitari Dexeus, Barcelona, Spain using these techniques are also presented.
Asunto(s)
Implantación del Embrión , Transferencia de Embrión/métodos , Fertilización In Vitro , Laboratorios , Técnicas de Cocultivo , Disección , Femenino , Humanos , Embarazo , Índice de Embarazo , Zona PelúcidaRESUMEN
Since the metabolic requirements of fertilization and early embryonic development are very different, we have tested a new culture medium (EllioStep2, Ellios Bio-Media, Paris, France) specially designed for the first cleavages and compared it with two conventional media: BM1 (Ellios Bio-Media, Paris, France) and IVF50 (Scandinavian IVF Science, Gothenburg, Sweden). In order to avoid any interference with fertilization, the test was performed as part of an intracytoplasmic sperm injection (ICSI) study. A total of 416 ICSI attempts were randomly performed using one or other of the media. After sperm injection, oocytes were incubated either in EllioStep2 or in BM1 or in IVF50. The embryo quality, pregnancy and implantation rates, number of frozen embryos were compared in the different media. The percentage of fair embryos (grades 4 and 3) was significantly higher when EllioStep2 was used than when oocytes was cultured in BM1 medium (54 versus 47%; P < 0.01) or in IVF50 (69 versus 61%; P < 0.01). The pregnancy rate per transfer and the implantation rate were not significantly higher with EllioStep2 than with BM1 or IVF50. However, the percentage of embryo freezings per attempt was significantly higher with EllioStep2 than with BM1 (47/105 versus 28/105; P < 0.01). In conclusion, the use of EllioStep2 is associated with an increase in embryo quality permitting a higher number of embryo freezings.
Asunto(s)
Medios de Cultivo/farmacología , Citoplasma , Embrión de Mamíferos/efectos de los fármacos , Micromanipulación , Oocitos , Espermatozoides , Adulto , Técnicas de Cultivo , Embrión de Mamíferos/fisiología , Femenino , Humanos , Masculino , EmbarazoRESUMEN
Co-culture of human embryos (n = 384 cycles) to the blastocyst stage using Vero cell monolayers was carried out between August 1995 and December 1997. A total of 2868 zygotes were co-cultured and 1027 embryos reached the blastocyst stage (blastocyst formation rate 35.8%). The blastocysts were frozen in 43.7% of patients. A mean of 1.8 blastocysts was transferred per patient and 95 pregnancies were obtained (pregnancy rate/cycle 24.7%). The blastocyst implantation rate was 23.6%. Miscarriage occurred in 15 patients (15.7%) and ectopic pregnancy in three (3.1%) patients. The multiple pregnancy rate was 32.6%. No differences were observed in the blastocyst rate between poor, normal or high response patients. Blastocyst formation was significantly lower when frozen donor spermatozoa were used. Significantly higher pregnancy rates per transfer and blastocyst implantation rates were attained when embryos were transferred on days 5 or 6 compared with day 7. No advantage was observed when co-culture was used in first cycle IVF patients, in comparison with conventional day 2 replacements. The use of blastocysts for preimplantation genetic diagnosis (PGD) increases the diagnostic reliability and widens diagnostic possibilities. A total of 215 cycles with frozen-thawed co-cultured blastocysts were carried out, with a pregnancy rate of 22.7% per replacement.
Asunto(s)
Implantación del Embrión/fisiología , Embrión de Mamíferos/fisiología , Células Vero/fisiología , Adulto , Animales , Peso al Nacer , Blastocisto/fisiología , Blastocisto/efectos de la radiación , Chlorocebus aethiops , Técnicas de Cocultivo , Transferencia de Embrión , Femenino , Fertilización In Vitro , Humanos , Rayos Láser , Persona de Mediana Edad , Embarazo , Índice de Embarazo , Razón de MasculinidadRESUMEN
We have analysed 11 human-specific Alu insertion polymorphisms in the Balkans to elucidate the origins of the Aromuns, a linguistic isolate inhabiting scattered areas in the Balkan Peninsula. Four Aromun samples (two from the Republic of Macedonia, one from Albania, and one from Romania) and five neighbouring populations (Macedonians, Albanians, Romanians, Greeks, and Turks) were analysed by means of genetic distances, principal components and analyses of the molecular variance (AMOVA). Three hypotheses were tested: Aromuns are Romanophonic Greeks; the result of a Romanian southward migration; or local descendants of the Thracians. The analyses show that the Aromuns do not constitute a homogeneous group separated from the rest of the Balkan populations. Grouping by language or geography does not explain the genetic differences observed in the region, suggesting a lack of genetic structure in the area. Aromuns do not seem to be particularly related to Greeks, Romanians, or to other Romance speakers. The Aromuns might have their origin to the south of the Danube river, with extensive gene flow with the neighbouring populations. The present results suggest a common ancestry of all Balkan populations, including Aromuns, with a lack of correlation between genetic differentiation and language or ethnicity, stressing that no major migration barriers have existed in the making of the complex Balkan human puzzle.
Asunto(s)
Elementos Alu , Elementos Transponibles de ADN , Etnicidad/genética , Polimorfismo Genético , Población Blanca/genética , Análisis de Varianza , Europa Oriental , Variación Genética , Grecia , Humanos , Lenguaje , TurquíaRESUMEN
OBJECTIVE: The objective of this study was to investigate if pediatric patients with benign brainstem encephalitis (Bickerstaff Syndrome) or with Miller-Fisher Syndrome are the extremes of the same nosological entity which, in adults, has been named ophalmoplegia-ataxia-areflexia syndrome. PATIENTS AND METHODS: The subjects included in the study were three patients of our institution and 24 patients found in the revision of the English and Spanish pediatric literature who fulfilled the diagnostic criteria of ophtalmoplegia-ataxia-areflexia syndrome. The topographical location of the lesion in the nervous system was based on previously established criteria by using clinical and complementary studies. RESULTS: Of the 27 patients included in the study we were able to reach an accurate topographical diagnosis in 9. None had an exclusive involvement of the peripheral nervous system, (6) had exclusively central nervous system involvement and 2 showed involvement of both system. In 12, the topographical location of the lesion could be only ascertained as probable; 3 of them in the peripheral nervous system, 2 in the central nervous system and mixed involvement in 7. In the remaining 7 patients there were insufficient clinical data to allow topographical classification. CONCLUSIONS: The ophtalmoplegia-ataxia-areflexia syndrome can also be found in pediatric patients. The lesion in the majority of patients in this age group is located in the central nervous system, either alone or combined with peripheral nervous system involvement.
Asunto(s)
Síndrome de Miller Fisher/diagnóstico , Niño , Preescolar , Femenino , Humanos , MasculinoAsunto(s)
Aborto Séptico/veterinaria , Leptospirosis/veterinaria , Enfermedades de los Porcinos/inmunología , Aborto Veterinario/epidemiología , Aborto Veterinario/etiología , Animales , Brotes de Enfermedades/veterinaria , Femenino , Leptospirosis/epidemiología , Leptospirosis/inmunología , Embarazo , España , Porcinos , Enfermedades de los Porcinos/epidemiologíaRESUMEN
El concepto de examen de rutina preoperatorio ha sido cuestionado en los últimos años,tanto a nivel de publicaciones científicas,como en la práctica clínica cotidiana.En el presente estudio retrospectivo se evalúa la utilidad de los siguientes exámenes hematológicos preoperatorios:tiempo parcial de tromboplastina(KPTT)tiempo de protombina y hematocrito,analizándose los parámetros de alteración.Se estudió la ecolución clínica de los pacientes con laboratorio anormal.El bajo porcentale de pacientes con pruebas alteradas y la prácticamente ausencia de complicaciones en este grupo,apoyan hipótesis de dar mayor importancia a la historia clínica y al examen físico para orientar evolución y/o factibilidad de la cirugía