RESUMEN

Homing, engraftment and proliferation of hematopoietic stem/progenitor cell (HSC/HPCs) are crucial steps required for success of a bone marrow transplant. Observation of these critical events is limited by the opaque nature of bone. Here we demonstrate how individual HSCs engraft in long bones by thinning one side of the tibia for direct and unbiased observation. Intravital imaging enabled detailed visualization of single Sca-1+, c-Kit+, Lineage- (SKL) cell migration to bone marrow niches and subsequent proliferation to reconstitute hematopoiesis. This longitudinal study allowed direct observation of dynamic HSC/HPC activities during engraftment in full color for up to 6 days in live recipients. Individual SKL cells, but not mature or committed progenitor cells, preferentially homed to a limited number of niches near highly vascularized endosteal regions, and clonally expanded. Engraftment of SKL cells in P-selectin and osteopontin knockout mice showed abnormal homing and expansion of SKL cells. CD150+, CD48- SKL populations initially engrafted in the central marrow region, utilizing only a subset of niches occupied by the parent SKL cells. Our study demonstrates that time-lapse imaging of tibia can be a valuable tool to understand the dynamic characteristics of functional HSC and niche components in various mouse models.

Asunto(s)

Células de la Médula Ósea/fisiología , Trasplante de Células Madre Hematopoyéticas , Tibia/citología , Animales , Movimiento Celular , Proliferación Celular , Ratones , Ratones Endogámicos C57BL , Osteopontina/fisiología , Nicho de Células Madre/fisiología

RESUMEN

BACKGROUND: New screening methods that can add predictive diagnostic value for aggressive (high-grade, Gleason score ⩾ 7) prostate cancer (PCa) are needed to reduce unnecessary biopsies for patients with non-aggressive PCa. This is particularly important for men presenting for an initial biopsy with an equivocal PSA in the 2-10 ng ml(-1) range. PCA3 and ERG are biomarkers that can add predictive value for PCa in urine; however, with a limited utility as a digital rectal exam (DRE) is required. METHODS: First-catch urine samples were collected at six sites from men scheduled to undergo a prostate biopsy. Exosomal RNA was extracted, RNA copy numbers of ERG and PCA3 were measured by reverse transcription-quantitative PCR (RT-qPCR), and the EXO106 score (the sum of normalized PCA3 and ERG RNA levels) was computed. Performance was compared with standard of care (SOC; PSA, age, race or family history) parameters. Contingency table, logistic regression, receiver operating characteristics curve and box-plot analyses were performed. RESULTS: In this cohort (N=195), a dichotomous EXO106 score demonstrated good clinical performance in predicting biopsy result for both any cancer and high-grade disease. For high-grade disease, the negative and positive predictive values were 97.5% and 34.5%, respectively. The discrimination between high-grade and Gleason score ⩽ 6 (including benign) biopsy results by a combination of EXO106 and SOC (area under the curve (AUC)=0.803) was significantly improved compared with SOC without EXO106 (AUC=0.6723, P=0.0009). The median EXO106 score correlated (P<0.001; Spearman's rank order) with histologic grade. CONCLUSIONS: A novel molecular signature (EXO106 score) derived from non-DRE urine demonstrated independent, negative predictive value for the diagnosis of high-grade PCa from initial biopsy for men with 'gray zone' serum PSA levels. Its use in the biopsy decision process could result in fewer prostate biopsies for clinically insignificant disease.

Asunto(s)

Antígenos de Neoplasias/genética , Biomarcadores de Tumor , Exosomas/genética , Neoplasias de la Próstata/diagnóstico , Neoplasias de la Próstata/genética , ARN , Transactivadores/genética , Adulto , Anciano , Anciano de 80 o más Años , Biopsia , Humanos , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Pronóstico , Neoplasias de la Próstata/orina , ARN/orina , Curva ROC , Reproducibilidad de los Resultados , Regulador Transcripcional ERG

RESUMEN

INTRODUCTION: Outcomes-based education has been the core of the curriculum strategy of the Nottingham School of Veterinary Medicine and Science (SVMS) since its inception in 2006. As part of the ongoing curriculum evaluation, the first two graduating cohorts were invited to provide an appraisal of their preparation by the SVMS curriculum for their role in clinical practice. This paper provides brief accounts of the SVMS curriculum model, the development of the evaluation instrument and the findings of the alumni survey. MATERIALS AND METHODS: The evaluation instrument contained 25 attributes expected of SVMS graduates. Alumni rated their preparation for practice in relation to each attribute. RESULTS: The four highest rated characteristics were compassion for animals and the application of ethics to animal welfare; communication skills; recognising own limitations and seeking help and advice where needed and clinical examination skills. The four lowest rated were clinical case management and therapeutic strategies; dealing with veterinary public health and zoonotic issues; knowledge of current veterinary legislation and dealing with emergency and critical care cases. Free text responses were in line with these quantitative findings. CONCLUSION: The results indicate that this sample of SVMS graduates were satisfied with their undergraduate education and felt well prepared for their role in clinical practice.

RESUMEN

Many changes associated with bariatric surgery have the potential to affect warfarin dosing; yet current literature includes little data describing this phenomenon. Investigating this relationship may allow for determination of post-bariatric surgery warfarin dosing using stable pre-operative dosing levels. A retrospective chart review was completed for 10 patients stabilized on chronic warfarin therapy who underwent bariatric surgery. Data collection consisted of the following: warfarin requirement in mg/week, time in target range (TTR), creatinine, liver function, diarrhoea, medication changes, diet, and signs of bleeding and/or thrombosis. Three study patients underwent laparoscopic adjustable gastric banding procedures and seven patients underwent Roux-en-Y gastric bypass. The average (standard deviation) weekly warfarin dose required in the immediate post-operative interval was 64% (25%) of baseline dosing, corresponding to a TTR of 48%. At 6 months, patients required 85% (19%) of baseline weekly dosing, with TTR of 53.4%. At 1 year, dosing was 90% (16%) of baseline with TTR of 63.5%. Patients underwent medication changes as well as transient bouts of diarrhoea. Two patients suffered unspecified haemorrhages of the gastrointestinal tract (international normalized ratio [INR] = 2.3 and 9.8). This patient set demonstrated an initial drop in warfarin requirement, followed by escalating dosing trends that became more predictable as patients were farther out from procedure.

Asunto(s)

Anticoagulantes/administración & dosificación , Anticoagulantes/farmacología , Coagulación Sanguínea/efectos de los fármacos , Warfarina/administración & dosificación , Warfarina/farmacología , Adulto , Cirugía Bariátrica , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos

RESUMEN

OBJECTIVE: In the United States of America, 6.2 million individuals are using elliptical motion trainers in fitness centres. However, graded exercise test protocols to estimate peak oxygen consumption (VO(2peak)) using elliptical motion trainers have not been developed for the general population. METHODS: Fifty-nine subjects (mean age: 23.5 +/- 4.1 years) were randomly divided into a validation (VAL: n = 39) or cross-validation (XVAL: n = 20) group. Peak oxygen consumption (ml x kg(-1) x min(-1)) was measured via indirect calorimetry on an elliptical motion trainer for both groups. Subjects exercised at 150 strides x min(-1) against a resistance of four and a crossramp of 8%. The resistance was increased every two minutes by two units until exhaustion. For the VAL group, a stepwise regression analysis was used to predict VO(2peak) from resistance, maximal heart rate (HR(max)), body mass index (BMI), height and gender (female = 0, male = 1). RESULTS: The prediction equation derived from this study was VO(2peak) (ml x kg(-1) x min(-1)) = 187.39403 + 12.97271 (gender) - 1.45311 (height) - 1.21604 (BMI) - 0.19613 (HR(max)) + 1.57093 (resistance) (R2 = 0.76, SEE = 4.47, p < 0.05). Using this equation, the predicted VO(2peak) of the XVAL group was 45.18 +/- 6.42 ml x kg(-1) x min(-1), while the measured VO(2peak) was 43.55 +/- 6.23 ml x kg(-1) x min(-1) CONCLUSION: No significant difference was found between the measured and predicted VO(2peak) in the XVAL group. Therefore, it appears this protocol and equation will allow individuals to accurately estimate their VO(2peak) without using direct calorimetry. However future studies should investigate the validity of this protocol with diverse populations.

Asunto(s)

Prueba de Esfuerzo/métodos , Ejercicio Físico/fisiología , Consumo de Oxígeno/fisiología , Adulto , Algoritmos , Prueba de Esfuerzo/instrumentación , Femenino , Humanos , Masculino , Análisis de Regresión , Adulto Joven

RESUMEN

This study compared the effects of aerobic, resistance and concurrent aerobic and resistance training on pulmonary function and cardiorespiratory endurance in at-risk smokers. 50 sedentary, male smokers with pulmonary function impairments at risk for developing chronic lung diseases were randomly assigned to an aerobic (AerG;n=12), resistance (ResG;n=13), concurrent (ConG;n=13) or non-exercising control (NexG;n=12) group for 16 weeks. AerG subjects performed 45 min of aerobic exercise at 60%HR(max), ResG subjects performed 8 resistance exercises at 60%1-RM for 3 sets, 15 repetitions while ConG subjects performed both aerobic and resistance exercises. ANOVA revealed no significant difference between the groups in their pre-/post-test changes for FEV(1)/FVC ratio (AerG:-4.13%; ResG:-2.13%; ConG:-0.56%); FEF-50 (AerG:-4.59%; ResG:-7.62%; ConG:5.76%), FEF-75 (AerG:-2.36%; ResG:-7.62%; ConG:10.71%) and FEF 25-75 (AerG:-3.53%; ResG:-6.43%; ConG:7.63%). Significant differences were found between the groups in their pre-/post-test changes for FVC (AerG:8.05%; ResG:7.22%; ConG:11.55%), FEV(1) (Aer:9.60%;ResG:5.13%; ConG:12.10%), PEF (AerG: 11.29%; ResG:7.49%; ConG:20.18%), PIF (AerG:24.80%; ResG:19.41%; ConG:28.15%), IVC (AerG: 9.04%; ResG: 6.21%; ConG:16.35%), FEF-25 (AerG:5.88%; ResG:5.37%; ConG:11.88%) and cardiorespiratory fitness (AerG:25.44%; ResG:11.59%; ConG:22.83%). Post-hoc analysis revealed concurrent and aerobic training were equally effective at improving PIF and cardiorespiratory fitness with concurrent training most effective at improving FVC, FEV(1), PEF, IVC and FEF-25. This suggests synergy between aerobic and resistance exercise in preventing or reducing the detrimental effects of smoking while gaining the unique benefits of each mode of exercise.

Asunto(s)

Ejercicio Físico/fisiología , Resistencia Física/fisiología , Entrenamiento de Fuerza/métodos , Fumar , Adulto , Análisis de Varianza , Volumen Espiratorio Forzado , Humanos , Masculino , Pruebas de Función Respiratoria , Conducta Sedentaria , Capacidad Vital , Adulto Joven

RESUMEN

This study was designed to compare the effects of aerobic and concurrent aerobic and resistance training on their ability to slow the rate of development and progression of coronary heart disease (CHD) in young adult males at low risk, as determined by the Framingham risk assessment (FRA) score. Subjects were assigned to 16 weeks of three-times weekly aerobic training (AT) (n = 13), concurrent aerobic and resistance training (CART) (n = 13) or no exercise (NO) (n = 12). Both AT and CART resulted in significant (p < 0.05) changes in total cholesterol (from 173.67 ± 29.93 to 161.75 ± 26.78 mg.dl(-1) and from 190.00 ± 38.20 to 164.31 ± 28.73 mg.dl(-1), respectively), smoking status (from 12.25 ± 5.08 to 10.33 ± 5.37 cigarettes per day and 12.00 ± 4.71 to 8.77 ± 5.10 cigarettes per day, respectively), high-density lipoprotein cholesterol (from 47.00 ± 11.85 to 57.50 ± 5.99 mg.dl(-1) and 34.00 ± 8.53 to 46.77 ± 14.32 mg.dl(-1), respectively), systolic blood pressure (from 126.17 ± 7.00 to 122.33 ± 3.17 mmHg and 131.54 ± 9.28 to 121.69 ± 7.87 mmHg, respectively) and therefore FRA score (from 3.58 ± 2.19 to 1.33 ± 2.27 and 5.77 ± 3.09 to 2.46 ± 2.90, respectively). Both modes of exercise were found to be equally effective in reducing CHD risk. These findings support the inclusion of resistance training into an aerobic training programme to lower CHD risk, which will afford subjects the unique benefits of each mode of exercise.

Asunto(s)

Enfermedad Coronaria/prevención & control , Ejercicio Físico , Entrenamiento de Fuerza , Adulto , Colesterol/sangre , HDL-Colesterol/sangre , Enfermedad Coronaria/sangre , Humanos , Masculino , Factores de Riesgo

RESUMEN

The efficacy of a recently engineered single chain recombinant equine follicle stimulating hormone (reFSH) was investigated in estrous cycling mares whose gonadotropins and follicular activity had been suppressed by concurrent treatment with progesterone and estradiol (P&E). Time of estrus was synchronized in 15 estrous cycling mares during the breeding season with prostaglandins F(2alpha) (PGF(2alpha)). The day after ovulation, mares were treated once daily with P&E for 14 days. Mares received a second injection of PGF(2alpha) on day 6 of the synchronized estrous cycle to induce luteolysis. On day 8 post-ovulation mares were randomly assigned to three groups: small dose reFSH-treatment group (0.5mg reFSH IV, twice daily); large dose reFSH-treatment group (0.85mg reFSH IV twice daily); control group (saline IV, twice daily). reFSH treatment occurred concurrently with the last week of P&E treatment. After a follicle or cohort of follicles reached 35mm in diameter, mares were injected with 0.75mg of recombinant equine luteinizing hormone (reLH) to induce ovulation. Post-treatment ovulation was assessed. Daily blood samples were collected for analysis of FSH, LH, estradiol, progesterone, and inhibin by radioimmunoassay (RIA). On the first day of reFSH/saline treatment, blood samples were collected periodically from 1h prior to treatment to 6h post-injection via an indwelling jugular catheter to determine acute changes in FSH concentrations. Monitoring of follicular activity, estrus, and ovulation was performed daily by utilizing a stallion and transrectal ultrasonography. A difference (por=35mm follicles (days 16-21) than controls. Mares treated with reFSH, at either dose, took less time (average: 2.95+/-0.42 days) to develop 2-3 times more pre-ovulatory follicles than control mares (7.8+/-0.51 days) (p

Asunto(s)

Gonadotropinas Equinas/uso terapéutico , Caballos , Folículo Ovárico/efectos de los fármacos , Inducción de la Ovulación/métodos , Inhibición de la Ovulación/efectos de los fármacos , Algoritmos , Animales , Células CHO , Cricetinae , Cricetulus , Dinoprost/administración & dosificación , Sincronización del Estro/métodos , Sincronización del Estro/fisiología , Femenino , Hormona Folículo Estimulante/farmacología , Hormona Folículo Estimulante/uso terapéutico , Gonadotropinas Equinas/farmacología , Caballos/fisiología , Inyecciones Intramusculares , Modelos Biológicos , Folículo Ovárico/citología , Folículo Ovárico/fisiología , Inducción de la Ovulación/veterinaria , Inhibición de la Ovulación/fisiología , Proteínas Recombinantes/farmacología , Proteínas Recombinantes/uso terapéutico , Resultado del Tratamiento

RESUMEN

BACKGROUND: To compare the core hand and knee examination skills gained by undergraduates taught either by trained patient educators (PEs) or by doctors. METHODS: A total of 50 final year medical students were randomized to receive training from PEs or doctors. Group A were taught hand examination by a PE with rheumatoid arthritis, and knee examination by a PE with osteoarthritis. Group B was taught hand and knee examination by a consultant rheumatologist plus an untrained patient with appropriate signs. All students were taught an established core skills set in small group workshops. Students then undertook two validated objective structured clinical examination (OSCE) stations with two blinded assessors. Pre- and post-teaching questionnaires established the students' self-reported levels of skills (SRS) and a student evaluation of teaching (SET). The study was analysed as an equivalence trial. A mean difference in OSCE scores of 10% was assumed to be of educational significance. RESULTS: Although the SET scores of both groups were high, the doctor-led group received higher scores. Aside from this, the two student groups did not differ significantly. There were no significant differences in mean hand OSCE (mean difference = 0.88, P = 0.28, 95% CI = -0.73 to 2.49) or knee OSCE (mean difference = 0.28, P = 0.7, 95% CI = -1.19 to 1.75) scores. Both the upper and lower confidence intervals for each mean difference fell within the 10% range (-2.8 to 2.8 for the hand, and -2.5 to 2.5 for the knee) and equivalence was assumed. CONCLUSIONS: Adequately trained PEs can deliver clearly structured undergraduate skills, teaching with equivalent learning outcomes to those of rheumatology consultants. PEs are a valuable development to augment musculoskeletal education in the face of expanding student numbers.

Asunto(s)

Educación de Pregrado en Medicina/métodos , Enfermedades Musculoesqueléticas/diagnóstico , Pacientes , Examen Físico/métodos , Reumatología/educación , Adulto , Anciano , Artritis Reumatoide/diagnóstico , Consultores , Evaluación Educacional/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Osteoartritis de la Rodilla/diagnóstico , Examen Físico/normas , Método Simple Ciego , Enseñanza/métodos

RESUMEN

The effect of androstenedione intake on serum hormone concentrations in women is equivocal. Therefore, we examined the hormonal response to androstenedione intake in healthy young (22.1 +/- 0.4 y) women for 4 hours. On day 3 of the follicular phase, subjects ingested placebo, 100, or 300 mg androstenedione in a random, double-blind, cross-over manner. Blood samples were collected before and every 30 min for 240 min after intake. Serum androstenedione concentrations (means +/- SE) increased above basal (6.2 +/- 0.8 nmol/l) from 60-240 min for both 100 mg (22.6 +/- 1.0 nmol/l at 240 min) and 300 mg (28.1 +/- 1.3 nmol/l at 210 min). Androstenedione intake increased serum total testosterone concentrations above basal (1.2 +/- 0.2 nmol/l) from 120-240 min (5.5 +/- 0.9 nmol/l at 210 min) with 100 mg and from 60-240 with 300 mg (10.2 +/- 1.6 nmol/l at 210 min). Androstenedione intake also increased serum estradiol concentrations (basal 191 +/- 24 pmol/l) at 150 min with 100 mg (237 +/- 35 pmol/l) and from 150-240 min with 300 mg (reaching 260 +/- 32 pmol/l at 240 min). These data indicate that, in contrast to men, androstenedione intake in women increases serum testosterone concentrations.

Asunto(s)

Androstenodiona/administración & dosificación , Estradiol/sangre , Testosterona/sangre , Adulto , Androstenodiona/sangre , Estudios Cruzados , Dieta , Método Doble Ciego , Ingestión de Energía , Ejercicio Físico , Femenino , Fase Folicular , Humanos , Cinética , Placebos

RESUMEN

The effectiveness of a nutritional supplement designed to enhance serum testosterone concentrations and prevent the formation of dihydrotestosterone and estrogens from the ingested androgens was investigated in healthy 30- to 59-year old men. Subjects were randomly assigned to consume DION (300 mg androstenedione, 150 mg dehydroepiandrosterone, 540 mg saw palmetto, 300 mg indole-3-carbinol, 625 mg chrysin, and 750 mg Tribulus terrestris per day; n = 28) or placebo (n = 27) for 28 days. Serum free testosterone, total testosterone, androstenedione, dihydrotestosterone, estradiol, prostate-specific antigen (PSA), and lipid concentrations were measured before and throughout the 4-week supplementation period. Serum concentrations of total testosterone and PSA were unchanged by supplementation. DION increased (p < 0.05) serum androstenedione (342%), free testosterone (38%), dihydrotestosterone (71%), and estradiol (103%) concentrations. Serum HDL-C concentrations were reduced by 5.0 mg/dL in DION (p < 0.05). Increases in serum free testosterone (r2 = 0.01), androstenedione (r2 = 0.01), dihydrotestosterone (r2 = 0.03), or estradiol (r2 = 0.07) concentrations in DION were not related to age. While the ingestion of androstenedione combined with herbal products increased serum free testosterone concentrations in older men, these herbal products did not prevent the conversion of ingested androstenedione to estradiol and dihydrotestosterone.

Asunto(s)

Adyuvantes Inmunológicos/uso terapéutico , Androstenodiona/uso terapéutico , Deshidroepiandrosterona/uso terapéutico , Suplementos Dietéticos , Hormonas Esteroides Gonadales/sangre , Fitoterapia , Preparaciones de Plantas/uso terapéutico , Adulto , Factores de Edad , Análisis de Varianza , Método Doble Ciego , Humanos , Masculino , Persona de Mediana Edad , Testosterona/sangre

RESUMEN

OBJECTIVE: The effectiveness of an androgenic nutritional supplement designed to enhance serum testosterone concentrations and prevent the formation of dihydrotestosterone and estrogen was investigated in healthy 3 to 58 year old men. DESIGN: Subjects were randomly assigned to consume a nutritional supplement (AND-HB) containing 300-mg androstenediol, 480-mg saw palmetto, 450-mg indole-3-carbinol, 300-mg chrysin, 1,500 mg gamma-linolenic acid and 1.350-mg Tribulus terrestris per day (n = 28), or placebo (n = 27) for 28 days. Subjects were stratified into age groups to represent the fourth (30 year olds, n = 20), fifth (40 year olds, n = 20) and sixth (50 year olds, n = 16) decades of life. MEASUREMENTS: Serum free testosterone, total testosterone, androstenedione, dihydrotestosterone, estradiol, prostate specific antigen and lipid concentrations were measured before supplementation and weekly for four weeks. RESULTS: Basal serum total testosterone, estradiol, and prostate specific antigen (PSA) concentrations were not different between age groups. Basal serum free testosterone concentrations were higher (p < 0.05) in the 30- (70.5 +/- 3.6 pmol/L) than in the 50 year olds (50.8 +/- 4.5 pmol/L). Basal serum androstenedione and dihydrotestosterone (DHT) concentrations were significantly higher in the 30- (for androstenedione and DHT, respectively, 10.4 +/- 0.6 nmol/L and 2198.2 +/- 166.5 pmol/L) than in the 40- (6.8 +/- 0.5 nmol/L and 1736.8 +/- 152.0 pmol/L) or 50 year olds (6.0 +/- 0.7 nmol/L and 1983.7 +/- 147.8 pmol/L). Basal serum hormone concentrations did not differ between the treatment groups. Serum concentrations of total testosterone and PSA were unchanged by supplementation. Ingestion of AND-HB resulted in increased (p < 0.05) serum androstenedione (174%), free testosterone (37%), DHT (57%) and estradiol (86%) throughout the four weeks. There was no relationship between the increases in serum free testosterone, androstenedione, DHT, or estradiol and age (r2 = 0.08, 0.03, 0.05 and 0.02, respectively). Serum HDL-C concentrations were reduced (p < 0.05) by 0.14 mmol/L in AND-HB. CONCLUSIONS: These data indicate that ingestion of androstenediol combined with herbal products does not prevent the formation of estradiol and dihydrotestosterone.

Asunto(s)

Anabolizantes/administración & dosificación , Androstenodiol/administración & dosificación , Suplementos Dietéticos , Estradiol/sangre , Testosterona/sangre , Administración Oral , Adulto , Factores de Edad , Androstenodiona/sangre , HDL-Colesterol/sangre , LDL-Colesterol/sangre , Método Doble Ciego , Humanos , Masculino , Persona de Mediana Edad , Placebos , Antígeno Prostático Específico/sangre , Factores de Tiempo

Asunto(s)

Competencia Clínica , Educación en Odontología , Humanos , Reino Unido

RESUMEN

OBJECTIVES: Neurologic and vascular structures are at risk of iatrogenic injury from proximal interlocking screw insertion after retrograde nailing. This risk may increase in the presence of acetabular fractures because of the displacement of soft tissues resulting from hematoma. The purpose of this study was to establish and compare the relative safe zones (RSZs) for interlocking screw insertion in adults with and without concomitant acetabular fractures. MATERIALS AND METHODS: Thirty pelvic computed tomography scans of patients with acute unilateral acetabular fracture and magnetic resonance imaging scans of five healthy legs were used to evaluate the course of the femoral sheath, neurovascular complex, and the sciatic nerve as they course through the proximal thigh in sixty-five limbs. RESULTS: The anatomy of the neurovascular structures on the fractured side was statistically different from that of the normal side. On the normal side, the RSZ at the lesser trochanteric level was identified from +7 degrees medial to +20 degrees lateral to the sagittal axis (27-degree angle zone) for anteroposterior screw placement. These values for the fractured side, respectively, changed to +1 degrees and +14 degrees (13-degree angle zone), a 52 percent decrease. The RSZ for lateral-medial screw placement was 28 degrees anterior to 39 degrees posterior to the coronal axis (67-degree angle zone) for the normal side, which changed, respectively, to 32 degrees and 41 degrees (73-degree angle zone) for the fractured side. At the level of the lesser trochanter, rotation in the femoral shaft was mimicked only in part (approximately 50 percent) by the neurovascular structures. CONCLUSION: Lateral-medial screw insertion is safer than anteroposterior insertion. Anteroposterior screw insertion becomes even more critical if the acetabulum is fractured. Femoral external rotation after rod insertion, but before screw insertion, will enlarge the safe zones.

Asunto(s)

Acetábulo/lesiones , Tornillos Óseos/efectos adversos , Fracturas del Fémur/diagnóstico , Fracturas del Fémur/cirugía , Fijación Intramedular de Fracturas/efectos adversos , Complicaciones Intraoperatorias/etiología , Adulto , Arterias/lesiones , Clavos Ortopédicos , Seguridad de Equipos , Femenino , Fijación Intramedular de Fracturas/instrumentación , Humanos , Complicaciones Intraoperatorias/diagnóstico , Imagen por Resonancia Magnética , Masculino , Traumatismos de los Nervios Periféricos , Probabilidad , Medición de Riesgo , Factores de Riesgo , Sensibilidad y Especificidad , Tomografía Computarizada por Rayos X , Venas/lesiones

RESUMEN

Samarium(II) iodide was used to access eight-, nine-, and ten-membered carbocycles via a domino reaction composed of a cyclization/fragmentation process. 2-(Iodoalkyl)-, 2-(iodomethyl)allyl-, and 2-(2-iodomethyl)benzyl-2-methyl-3-(methanesulfonyloxy)cycloalkanones were subjected to Barbier-type reductive coupling conditions. Intermediate cycloalkanedione derivatives were also treated under similar conditions, providing bicyclic hydroxy ketones with complete diastereoselectivity and high yields. This method represents a general and efficient approach to a variety of highly functionalized, stereodefined carbocycles.

Asunto(s)

Alcanos/química , Yoduros/química , Samario/química , Alquilación , Ciclización , Cetonas/química , Oxidación-Reducción

RESUMEN

Recently, the authors have used the computer-generated three-dimensional (3-D) CT moving images for preoperative planning and screw/pin insertion in more than 28 cases involving plate and screw fixation of complex acetabular fractures. The authors also used stereolithography (wax or plastic 3-D model of bony anatomy) to develop a computer-generated "clip on" interpositioning template for accurate placement of plate and screws. Application of these new technologies gives the surgeon precise information about the fracture patterns and provides an effective means for preoperative planning and accurate fixation of acetabular fractures. The accuracy of the 3-D virtual presentation of the anatomy is impressive and was substantiated by phantom studies. Postoperation CT revealed no case of screw penetration in the joint. Among other benefits over conventional surgical technique, the computer-assisted surgery provided decreased operative time and morbidity, decreased radiation exposure, and obviated the need for oblique, inlet and outlet roentgen views of the pelvis for preoperative planning. A case report specifically demonstrates preoperative planning for reconstruction of acetabular fracture.

Asunto(s)

Acetábulo/lesiones , Fracturas Óseas/diagnóstico por imagen , Fracturas Óseas/cirugía , Imagenología Tridimensional , Tomografía Computarizada por Rayos X , Acetábulo/cirugía , Adulto , Humanos , Masculino

RESUMEN

In young men, chronic ingestion of 100 mg androstenedione (ASD), three times per day, does not increase serum total testosterone but does increase serum estrogen and ASD concentrations. We investigated the effects of ASD ingestion in healthy 30- to 56-yr-old men. In a double-blind, randomly assigned manner, subjects consumed 100 mg ASD three times daily (n = 28), or placebo (n = 27) for 28 days. Serum ASD, dihydrotestosterone (DHT), free and total testosterone, estradiol, prostate-specific antigen (PSA), and lipid concentrations were measured at week 0 and each week throughout the supplementation period. Serum total testosterone and PSA concentrations did not change with supplementation. Elevated serum concentrations of ASD (300%), free testosterone (45%), DHT (83%), and estradiol (68%) were observed during weeks 1-4 in ASD (P < 0.05). There was no relationship between age and changes in serum ASD (r2 = 0.024), free testosterone (r2 = 0.00), or estradiol (r2 = 0.029) concentrations with ASD, whereas the serum DHT response to ASD ingestion was related to age (r2 = 0.244; P < 0.05). Serum concentrations of high-density lipoprotein cholesterol were decreased by 10% during the supplementation period (P < 0.05). These results suggest that the ingestion of 100 mg ASD, three times per day, does not increase serum total testosterone or PSA concentrations but does elicit increases in ASD, free testosterone, estradiol, and DHT and decreases serum high-density lipoprotein cholesterol concentrations.

Asunto(s)

Afecto , Androstenodiona/sangre , Androstenodiona/farmacología , Testosterona/sangre , Administración Oral , Adulto , Factores de Edad , Androstenodiona/administración & dosificación , Colesterol/sangre , HDL-Colesterol/sangre , LDL-Colesterol/sangre , Método Doble Ciego , Estradiol/sangre , Humanos , Masculino , Persona de Mediana Edad , Placebos , Antígeno Prostático Específico/sangre , Factores de Tiempo

RESUMEN

The effects of androgen precursors, combined with herbal extracts designed to enhance testosterone formation and reduce conversion of androgens to estrogens was studied in young men. Subjects performed 3 days of resistance training per week for 8 weeks. Each day during Weeks 1, 2, 4, 5, 7, and 8, subjects consumed either placebo (PL; n = 10) or a supplement (ANDRO-6; n = 10), which contained daily doses of 300 mg androstenedione, 150 mg DHEA, 750 mg Tribulus terrestris, 625 mg Chrysin, 300 mg Indole-3-carbinol, and 540 mg Saw palmetto. Serum androstenedione concentrations were higher in ANDRO-6 after 2, 5, and 8 weeks (p <.05), while serum concentrations of free and total testosterone were unchanged in both groups. Serum estradiol was elevated at Weeks 2, 5, and 8 in ANDRO-6 (p <.05), and serum estrone was elevated at Weeks 5 and 8 (p <.05). Muscle strength increased (p <.05) similarly from Weeks 0 to 4, and again from Weeks 4 to 8 in both treatment groups. The acute effect of one third of the daily dose of ANDRO-6 and PL was studied in 10 men (23 +/- 4 years). Serum androstenedione concentrations were elevated (p <.05) in ANDRO-6 from 150 to 360 min after ingestion, while serum free or total testosterone concentrations were unchanged. These data provide evidence that the addition of these herbal extracts to androstenedione does not result in increased serum testosterone concentrations, reduce the estrogenic effect of androstenedione, and does not augment the adaptations to resistance training.

Asunto(s)

Adaptación Fisiológica/efectos de los fármacos , Androstenodiona/farmacología , Deshidroepiandrosterona/farmacología , Fitoterapia , Testosterona/sangre , Adulto , Andrógenos , Androstenodiona/administración & dosificación , Antropometría , Antioxidantes/administración & dosificación , Antioxidantes/farmacología , HDL-Colesterol/efectos de los fármacos , Deshidroepiandrosterona/administración & dosificación , Método Doble Ciego , Antagonistas de Estrógenos/administración & dosificación , Antagonistas de Estrógenos/farmacología , Flavonoides/administración & dosificación , Flavonoides/farmacología , Humanos , Indoles/administración & dosificación , Indoles/farmacología , Masculino , Músculo Esquelético/fisiología , Extractos Vegetales/administración & dosificación , Extractos Vegetales/farmacología , Rosales , Serenoa , Levantamiento de Peso

RESUMEN

The mechanical performance of bone screws is determined by their pull-out strength (holding power), compressive force, stripping torque, yield bending moment, ultimate bending moment, and fatigue strength. These parameters are related to the parameters of the screw design, including major thread diameter, minor thread diameter, thread length, pitch, shaft diameter, cannulation diameter, and material properties. The goal of the study was to theoretically predict the static performance of five 4.0-mm, 45-46-mm-long, cancellous, partially threaded standard and cannulated bone screws and compare the predictions with experimental measurements. A secondary goal was to determine if cannulation of the bone screw diminished its mechanical performance. The predicted values for pull-out force, compressive force, and stripping torque were determined by the thread length, major thread diameter, and thread shape factor. The screws with the largest major thread diameter and longest thread length had the greatest pull-out force, compressive strength, and stripping torque. However, when correcting for the thread length, a higher thread shape factor compensated for a smaller major diameter. The coefficient of determination (r2) for the correlation between the predicted and measured pull-out force improved from 0.75 to 0.90 when the theoretical model included the thread shape factor. The yield and ultimate bending moments are a function of the section modulus and material properties of the screw. The Ace solid screw had the greatest section modulus and yield and ultimate bending moments. The experimental data support the theoretical models for predicting the mechanical performance of bone screws. The design of the bone screws can be optimized on the basis of theoretical modeling. The strong correlation between the predicted and measured parameters allows comparison between bone screws without repeated experimental tests. Theoretical and experimental results show that cannulation of the bone screw did not inherently diminish its mechanical performance.

Asunto(s)

Tornillos Óseos , Fenómenos Biomecánicos , Humanos

RESUMEN

A review of the existing data on shoulder laxity in females reveals there are insufficient data to confirm the commonly held belief that shoulders in females are more lax than shoulders in males. Laxity is not synonymous with instability. Although females may have increased generalized joint laxity relative to males, generalized joint laxity does not correlate with shoulder laxity. There is conflicting data regarding shoulder laxity and gender. A review of patients with multidirectional instability who were treated operatively showed that 55% of the patients were female (N = 94) and 45% were male (N = 77), but the number or gender of patients who were treated nonoperatively was not reported. Multidirectional instability is reviewed in the context of the lax shoulder in the female. Initial treatment should be nonoperative, emphasizing physical therapy and dynamic stabilization of the shoulder. If nonoperative treatment fails, open or arthroscopic inferior capsular shift stabilization is recommended. Additional basic science and clinical trials are needed to determine whether thermal capsulorrhaphy should be considered in the treatment of patients with multidirectional instability of the shoulder.

Asunto(s)

Inestabilidad de la Articulación , Articulación del Hombro , Traumatismos en Atletas/diagnóstico , Traumatismos en Atletas/fisiopatología , Traumatismos en Atletas/terapia , Femenino , Humanos , Inestabilidad de la Articulación/diagnóstico , Inestabilidad de la Articulación/fisiopatología , Inestabilidad de la Articulación/terapia , Masculino , Caracteres Sexuales , Luxación del Hombro/diagnóstico , Luxación del Hombro/fisiopatología , Luxación del Hombro/terapia , Articulación del Hombro/fisiología , Articulación del Hombro/fisiopatología