The Influence of Social Systems on Patterns of Mitochondrial DNA Variation in Baboons.

Behavior is influenced by genes but can also shape the genetic structure of natural populations. Investigating this link is of great importance because behavioral processes can alter the genetic diversity on which selection acts. Gene flow is one of the main determinants of the genetic structure of a population and dispersal is the behavior that mediates gene flow. Baboons (genus Papio) are among the most intensely studied primate species and serve as a model system to investigate the evolution of social systems using a comparative approach. The general mammalian pattern of male dispersal and female philopatry has thus far been found in baboons, with the exception of hamadryas baboons (Papio hamadryas). As yet, the lack of data on Guinea baboons (Papio papio) creates a taxonomic gap in genus-wide comparative analyses. In our study we investigated the sex-biased dispersal pattern of Guinea baboons in comparison to hamadryas, olive, yellow, and chacma baboons using sequences of the maternally transmitted mitochondrial hypervariable region I. Analyzing whole-range georeferenced samples (N = 777), we found strong evidence for female-biased gene flow in Guinea baboons and confirmed this pattern for hamadryas baboons, as shown by a lack of genetic-geographic structuring. In addition, most genetic variation was found within and not among demes, in sharp contrast to the pattern observed in matrilocal primates including the other baboon taxa. Our results corroborate the notion that the Guinea baboons' social system shares some important features with that of hamadryas baboons, suggesting similar evolutionary forces have acted to distinguish them from all other baboons.

Computer-assisted surgery simulations and directed practice of total knee arthroplasty: educational benefits to the trainee.

Orthopaedic residents typically learn to perform total knee arthroplasty (TKA) through an apprenticeship-type model, which is a necessarily slow process. Surgical skills courses, using artificial bones, have been shown to improve technical and cognitive skills significantly within a couple of days. The addition of computer-assisted surgery (CAS) simulations challenges the participants to consider the same task in a different context, promoting cognitive flexibility. We designed a hands-on educational intervention for junior residents with a conventional tibiofemoral TKA station, two different tibiofemoral CAS stations, and a CAS and conventional patellar resection station, including both qualitative and quantitative analyses. Qualitatively, structured interviews before and after the course were analyzed for recurring themes. Quantitatively, subjects were evaluated on their technical skills before and after the course, and on a multiple-choice knowledge test and error detection test after the course, in comparison to senior residents who performed only the testing. Four themes emerged: confidence, awareness, deepening knowledge and changed perspectives. The residents' attitudes to CAS changed from negative before the course to neutral or positive afterwards. The junior resident group completed 23% of tasks in the pre-course skills test and 75% of tasks on the post-test (p<0.01), compared to 45% of tasks completed by the senior resident group. High-impact educational interventions, promoting cognitive flexibility, would benefit trainees, attending surgeons, the healthcare system and patients.

Hipercalcemia tumoral: a propósito de tres casos: [revisión] / Tumor related hypercalcemia: a review of three cases: [review]

Hypercalcemia is an infrecuent complication in pediatric oncology, with an incidence between 0,5 and 3 percent. It can occur at diagnosis, during the disease course or at relapse, and it is resolved by treating the underlying pathology, requiring in some cases the use of specific therapy such as calcitonin and biphosphonates. This article presents 3 cases of children with cancer and hypercalcemia during their illness, analyzing its clinical presentation, pathophysiology and treatment.

La hipercalcemia es una complicación infrecuente en niños con cáncer, con una incidencia que oscila entre 0,5 y 3 por ciento. Se puede presentar al diagnóstico, durante el tratamiento o en la recaída de una neoplasia, se resuelve al tratar la enfermedad de base, pudiendo además, requerir el uso de terapia específica como calcitonina y bifosfonatos. En el presente artículo se revisan 3 casos clínicos de niños con cáncer que presentaron hipercalcemia en algún momento de su enfermedad, se discute su forma de presentación, fisiopatología y manejo.

Basement membrane antibodies in sera of haematopoietic cell recipients are associated with graft-versus-host disease.

BACKGROUND: Graft-versus-host disease (GvHD) occurs frequently after haematopoietic cell transplantation (HCT). Mucocutaneous lesions of GvHD may mimic bullous autoimmune dermatoses, and 10 cases of concurrent GvHD and a bullous autoimmune disease have been reported in the literature. OBJECTIVE: To determine the frequency of circulating antibodies to the cutaneous basement membrane zone (BMZ) in HCT patients with GvHD in comparison with HCT patients without GvHD, psoriasis patients and healthy controls. SUBJECTS AND METHODS: We examined 42 patients with chronic GvHD, 18 HCT patients without GvHD, 11 psoriasis patients and 40 healthy controls, prospectively. Sera were tested by indirect immunofluorescence (IIF) on salt-split skin, NC16a-ELISA and immunoblot using keratinocyte extracts. Univariate statistical analyses and logistic regression were performed to assess possible correlations of graft and patient characteristics with the presence of BMZ antibodies. RESULTS: Circulating basement membrane zone (BMZ) antibodies were detected in 10/42 (24%) GvHD sera by immunoblot, but not in any of the HCT sera from patients without GvHD (0/18; 0%). The antibodies targeted collagen VII, BP230, collagen XVII/BP180 or p200/laminin gamma1. Clinically manifest bullous autoimmune dermatoses (bullous pemphigoid or epidermolysis bullosa acquisita) were found in two GvHD patients. 1/11 (9%) psoriasis sera and 1/40 (2.4%) healthy control sera reacted with collagen XVII or BP230, respectively. CONCLUSIONS: Circulating BMZ antibodies are significantly associated with chronic GvHD in contrast to uncomplicated HCT. Recurrent mucocutaneous lesions in chronic inflammatory skin disorders may liberate antigens, which may lead to production of BMZ antibodies, particularly in the context of GvHD-mediated reduced self-tolerance.

Características clínicas del púrpura trombocitopénico inmune: revisión de 52 casos / Clinical characteristics of inmune thrombocytopenic purpura

Introducción: El Púrpura Trombocitopénico Inmune (PTI) suele ser autolimitado pero 10-20 por ciento persisten a los 6 meses, es decir de evolución crónica. Su tratamiento es controvertido y existen pocos datos nacionales. Objetivo: Conocer algunas características clínicas y de laboratorio del PTI, su relación con evolución crónica y el manejo actual. Método: Estudio retrospectivo de los 52 pacientes con PTI evaluados en Hospital Luis Calvo Mackenna, entre marzo 1998 y febrero 2003. Se consignó: sexo, edad, manifestaciones clínicas, conducta terapéutica y recuento plaquetario (RP) al diagnóstico, 15-60 días y 6 meses. Se aplicaron Test de Fisher y Odd Ratio. Resultados: Mediana de edad: 4,4 años (0,7 a 16,1), el RP fue < - 20 000 x mm3 en 37/52. No hubo hemorragia del sistema nervioso central. Se manejó con observación clínica 34/52, corticoides 17/52 e inmunoglobulinas endovenosas con corticoides 1/52. Completaron control (6 meses) 48/52 pacientes. Presentaron curso crónico 11/48, asociado a RP 15 días < - 20 000 x mm3 (p = 0,01) OR = 9 (IC95 por ciento: 1,26-80,16) y RP a los 60 días < - 50 000 x mm3 (p = 0,0000003) OR= 124 (IC95 por ciento: 7,77 - 4951,52). Conclusiones: La mayoría de los pacientes requirieron sólo observación clínica. Presentaron evolución crónica 23 por ciento siendo factores de riesgo RP a los 15 días £ 20 000 x mm3 y RP a los 60 días £ 50 000 x mm3.

Dobutamine stress tele-echocardiography for evaluation of emergency department patients with chest pain.

OBJECTIVES: The practically and accuracy of dobutamine stress tele-echocardiography (DSTE) were assessed in patients presenting to the emergency department with chest pain. BACKGROUND: Many patients evaluated for chest pain in the emergency department (ED) are admitted to the hospital needlessly because of the difficulty in differentiating noncardiac chest pain from myocardial ischemia. METHODS: One hundred sixty-three patients with no evidence of myocardial infarction on initial blood studies or the electrocardiogram who were recommended for hospital admission to rule out myocardial infarction or myocardial ischemia were enrolled in this four-phase study. Rest echocardiography was performed in the ED, and the images were transmitted to a cardiologist for interpretation. If the results were normal, DSTE was then administered by a trained nurse. In the first three phases, all patients were admitted for observation regardless of the results of DSTE. In the fourth phase, those having normal DSTE results were able to be released. RESULTS: The test was completed within an average of 5.4 h of presentation to the ED. The sensitivity and specificity of DSTE versus clinical and cardiac catheterization findings were 89.5% and 88.9%, respectively, with a negative predictive value for DSTE of 98.5%. Patients experienced frequent mild side effects (54.7%), but few (6.3%) caused the test to be discontinued prematurely. In phase 4 of the study, 72% of those slated for hospital admission because of cardiac risk factors and chest pain suggesting myocardial ischemia were discharged after normal DSTE results. CONCLUSIONS: The use of DSTE in the evaluation of patients presenting with chest pain may improve screening for those who can be safely released from the ED.

Tunable liquid-crystal filter for solar imaging at the He i 1083-nm line.

A Lyot-Ohman filter for imaging near the solar He i 1083-nm line is described. Fast and continuous spectral tunability is provided by nematic liquid crystals. This solid-state filter has a free spectral range of 2.35 nm and a spectral resolution of 0.135 nm at the operating wavelength of 1083 nm. A wide-fielded design was used for both static and electro-optic retarder elements, facilitating use in fast imaging systems. A first-light He i image of the Sun is presented.

Emergency echocardiography telemedicine: an efficient method to provide 24-hour consultative echocardiography.

OBJECTIVES: This study sought to assess the clinical utility of interpreting emergency echocardiograms after regular working hours through a telemedicine connection to on-call cardiologists. BACKGROUND: Physician interpretation of emergency echocardiograms is often delayed during weekends, evenings or night hours. This delay places undue responsibility on less qualified personnel to interpret echocardiograms of vital importance. METHODS: Digital quad-screen cine-loop format was transmitted over standard telephone lines. Clinical data and conventional and telemedicine interpretations were collected prospectively for 187 emergent or semiemergent tele-echocardiograms after regular working hours. RESULTS: Indications for the echocardiogram included assessment of left ventricular function, ischemia, pericardial effusion, valvular disease, heart donor status and arrhythmia. Three off-site echocardiographers received the standard echocardiogram and spectral, gray-scale and color flow Doppler images in cineloop format using a laptop computer. Laptop interpretation showed 19 technically limited studied, 153 abnormal studies and 54% with wall motion abnormalities. Overall mean agreement rate between telemedicine laptop interpretation and conventional workstation interpretation performed in blinded manner for serious disorders with classic echocardiographic findings (pulmonary hypertension, left ventricular thrombus, aortic dissection, severe valvular insufficiency and large pericardial effusion) was 99.0% (95% confidence interval [CI] 96% to 99%). For serious wall motion abnormalities, the agreement rate was 96.3% (95% CI 92% to 99%). The following mean times elapsed after completion of the echocardiogram: to laptop fax report, 2.14 (range 10 min to 8 h); to dictation of videotape, 11.74 h (p < 0.001); to transcription of videotape diction, 56.6 h (p < 0.0001). CONCLUSIONS: After-hours emergency echocardiography telemedicine using a laptop computer is more rapid than scheduled conventional interpretation from a videotape workstation, yet diagnostic accuracy is comparable.

The feasibility of dobutamine stress echocardiography in the emergency department with telemedicine interpretation.

Dobutamine stress echocardiography (DSE) was performed on 26 patients admitted for chest pain deemed at low risk for myocardial infarction. Pharmacologic stress in the emergency department on a 24-hour basis was administered by nurses and echocardiographic ultrasonographers with electrocardiograms and echocardiograms being interpreted through telemedicine relay by an off-site cardiologist. Target heart rate was achieved in 84% of patients with an average peak dobutamine dose of 48 microg/kg/min. Echocardiographic transmission to the cardiologist over standard telephone lines took 9 minutes per quad-screen cine-loop display. The entire protocol added 2.2 hours to the emergency room evaluation. The one patient out of 26 who had incipient myocardial infarction was diagnosed by resting echocardiography. The remaining 25 patients were found clinically to have no infarction or ischemia. Of these, 22 out of 25 had normal DSE in the emergency department; three had wall motion abnormalities on peak stress images. Another three patients had other cardiac diseases documented by echocardiography. Evaluation of chest pain on a 24-hour basis with DSE with telemedicine interpretation appears to be a rapid and safe means of screening patients at low risk in the emergency department. Further experience with this modality is needed before all patients should be enrolled or early discharge of patients on the basis of DSE can be advised.

Intraoperative radiation with external irradiation: an alternative for nonresectable non-small-cell lung cancer?

In 15 patients with nonresectable non-small-cell lung carcinoma (NSCLC) (10 squamous, 1 large cell, 4 adenocarcinomas; T1-T3, N0-N2, all M0), lymph node dissection and intraoperative irradiation of the tumour (IORT) with doses between 10 and 20 Gy (11-20 MeV electron beam) was performed. Four weeks postoperatively 46-56 Gy external irradiation (8 or 23 MeV photons) was delivered to the mediastinum and 46 Gy to the tumour-bearing area. Four weeks postoperatively, 8 minor responses (MR, tumour regression between 4% and 45%) and 6 partial responses (PR, 50%-84%) were found. In 1 case, CT was inconclusive. Eighteen weeks after IORT, volumetry showed 3 CR, 9 PR (62% to 94%) and 1 28% MR. One patient died from intrabronchial hemorrhage 7 weeks after IORT (50% PR). Two others (both CR) died from unrelated causes, 6 and 12 months, respectively, after IORT. One patient (62% PR) died after 14 months from an unknown cause. Another patient died at 15 months from local relapse after CR. The latest CT volume assessment between 7.5 and 21.5 months, respectively, yielded 8 CR, and 1 63% PR. One further case of local CR has developed contralateral pulmonary metastasis after 10 months. All these patients are alive and well. The median time elapsed since IORT is 12.5 months, 10 patients have survived more than 12 months.