Selecting the best and brightest: A comparison of residency match processes in the United States and Canada

BACKGROUND:

Selecting candidates for plastic surgery residency training remains a challenge. In the United States, academic measures (United States Medical Licensing Exam Step I scores, medical school class rank and publications) are used as primary criteria for candidate selection for residency. In contrast, Canadian medical education de-emphasizes academic measures by using a pass-fail grading system. As a result, choosing residents from many qualified applicants may pose a challenge for Canadian programs without objective measures of academic success.

METHODS:

A 25-question online survey was distributed to program directors of Canadian plastic surgery residency-training programs. Program directors commented on number of yearly residents and applicants; application sections (ranked in importance using a Likert scale); interview invitation and rank-order list determination; and their satisfaction with the selection process.

RESULTS:

Ten Canadian plastic surgery program directors responded (90.9% response rate). The most important application components determining invitation to interview were letters of reference from a plastic surgeon (mean importance of 5.0 on the Likert scale), clinical electives in plastic surgery (mean 4.6) and electives with their program (mean 4.5). Applicants invited for interview were assessed on the quality of their responses to questions, maturity and personality. The majority of program directors agreed that a clinical elective with their program was important for consideration on their rank-order list. Program directors were neutral on their satisfaction with the selection process.

CONCLUSION:

Canadian plastic surgery residency programs emphasize clinical electives with their program and letters of reference from colleagues when selecting applicants for interviews. In contrast to their American counterparts, Canadian program directors rely on clinical interactions with prospective residents in the absence of objective academic measures.     

Breast cancer screening programmes: Challenging the coexistence with opportunistic mammography

Objective

This study investigated predictive factors of women's participation in organized mammography screening (OrgMS) and/or opportunistic mammography screening (OppMS) when the two screening modes coexist.

Methods

Questionnaires were sent to 6,000 women aged 51–74 years old invited to attend an OrgMS session between 2010 and 2011 in France. Data collected concerned the women's healthcare behaviour and their socioeconomic characteristics. Women without a personal or family history of breast cancer that could explain their participation in OppMS were retained in the generalized logits analysis.

Results

The data of 1,202 women were analysed. Of these, 555 (46.2%) had attended OrgMS only, 105 (8.7%) OppMS only and 542 (45.1%) had performed both OrgMS and OppMS. Multivariable analyses showed that women who had regular gynaecological check-ups were more likely to perform OppMS only or both OrgMS and OppMS, OR 95% CI were 2.1 [1.1–3.9], 1.9 [1.4–2.6], respectively. Being employed also increased participation in OppMS only [OR: 2.1 (1.2–3.7)] or both OrgMS and OppMS [OR: 1.5 (1.1–2.05)].

Conclusion and practice implications

In countries where OrgMS and OppMS coexist, strategies involving gynaecologists, referring doctors or company doctors and the organization of healthcare services to promote adequate screening round may help to reduce the overuse of mammography.     

Limiting glutamate transmission in a Vglut2-expressing subpopulation of the subthalamic nucleus is sufficient to cause hyperlocomotion

The subthalamic nucleus (STN) is a key area of the basal ganglia circuitry regulating movement. We identified a subpopulation of neurons within this structure that coexpresses Vglut2 and Pitx2, and by conditional targeting of this subpopulation we reduced Vglut2 expression levels in the STN by 40%, leaving Pitx2 expression intact. This reduction diminished, yet did not eliminate, glutamatergic transmission in the substantia nigra pars reticulata and entopeduncular nucleus, two major targets of the STN. The knockout mice displayed hyperlocomotion and decreased latency in the initiation of movement while preserving normal gait and balance. Spatial cognition, social function, and level of impulsive choice also remained undisturbed. Furthermore, these mice showed reduced dopamine transporter binding and slower dopamine clearance in vivo, suggesting that Vglut2-expressing cells in the STN regulate dopaminergic transmission. Our results demonstrate that altering the contribution of a limited population within the STN is sufficient to achieve results similar to STN lesions and high-frequency stimulation, but with fewer side effects.The subthalamic nucleus (STN) has long been a structure of interest for researchers and clinicians alike. There is ample evidence that high-frequency stimulation of the STN improves symptoms such as tremor, rigidity, and slowness of movement, so called bradykinesia, in patients with Parkinson disease (see ref. 1 for review), but the mechanism through which this is achieved is still unknown. Some studies suggest that electrical stimulation causes a hyperexcitation of this structure (2), whereas others find evidence that the opposite is true (3–5). Other possible interpretations include the activation of the zona incerta, a neighboring white-matter structure (6) or of fibers coming from the motor cortex (7). Bilateral lesions of the STN improve locomotion (8), a result that is consistent with the inactivation hypothesis. However, previous studies have also found cognitive side effects when using high-frequency stimulation of the STN (9), findings supported by lesion studies in experimental animals, which led to abnormalities in operant tasks involving attention and impulsivity (10, 11). The projections of the STN to other regions help explain the multiple roles of this structure: It sends projections to other targets in the basal ganglia, such as the internal segment of the globus pallidus [also termed the entopeduncular nucleus (EP) in rodents] and the substantia nigra pars reticulata (SNr) (12, 13). The STN is also part of a circuit that includes the prefrontal cortex and the nucleus accumbens (14). It is currently unknown, however, whether these different roles reflect a heterogeneous population of cells, characterized by distinct gene expression. If that is the case, it would allow direct control over each cell population, facilitating the investigation of their respective roles. In rodents, the STN is believed to be composed solely of glutamatergic neurons, characterized by expression of the subtype 2 Vesicular glutamate transporter (Vglut2), whereas the other two subtypes (Vglut1 and Vglut3) have not been detected (15, 16). Selective targeted deletion of Vglut2 expression in this nucleus would therefore provide a specific loss-of-function model that would bypass a common problem presented by traditional lesions with pharmacological agents, which have patterns of diffusion that likely affect surrounding structures (17). It is known, however, that Vglut2 is expressed in many other parts of the brain (18), and a complete knockout in the mouse is not viable (19, 20). There is also evidence that the promoter driving expression of the Paired-like homeodomain 2 (Pitx2) gene is strong in the mouse STN (21) but is also not specific to this structure and a full knockout of Pitx2 expression results in premature death (22). To achieve the desired level of specificity, using a conditional knockout technique previously used to eliminate glutamatergic transmission in other cell types (23), we crossed Pitx2-Cre and Vglut2-lox mice, producing Vglut2^{f/f;Pitx2-Cre} conditional knockout (cKO) mice in which Vglut2 expression in the STN was strongly reduced in comparison with expression levels in littermate control mice. To understand the physiological contribution of the selected subpopulation of STN cells, we characterized these cKO mice with regard to anatomical, electrophysiological, and molecular properties, as well as their performance in a range of behavioral tasks.     

Sleep Apnea and Nocturnal Cardiac Arrhythmia: A Populational Study

Background

The mechanisms associated with the cardiovascular consequences of obstructive sleep apnea include abrupt changes in autonomic tone, which can trigger cardiac arrhythmias. The authors hypothesized that nocturnal cardiac arrhythmia occurs more frequently in patients with obstructive sleep apnea.

Objective

To analyze the relationship between obstructive sleep apnea and abnormal heart rhythm during sleep in a population sample.

Methods

Cross-sectional study with 1,101 volunteers, who form a representative sample of the city of São Paulo. The overnight polysomnography was performed using an EMBLA® S7000 digital system during the regular sleep schedule of the individual. The electrocardiogram channel was extracted, duplicated, and then analyzed using a Holter (Cardio Smart®) system.

Results

A total of 767 participants (461 men) with a mean age of 42.00 ± 0.53 years, were included in the analysis. At least one type of nocturnal cardiac rhythm disturbance (atrial/ventricular arrhythmia or beat) was observed in 62.7% of the sample. The occurrence of nocturnal cardiac arrhythmias was more frequent with increased disease severity. Rhythm disturbance was observed in 53.3% of the sample without breathing sleep disorders, whereas 92.3% of patients with severe obstructive sleep apnea showed cardiac arrhythmia. Isolated atrial and ventricular ectopy was more frequent in patients with moderate/severe obstructive sleep apnea when compared to controls (p < 0.001). After controlling for potential confounding factors, age, sex and apnea-hypopnea index were associated with nocturnal cardiac arrhythmia.

Conclusion

Nocturnal cardiac arrhythmia occurs more frequently in patients with obstructive sleep apnea and the prevalence increases with disease severity. Age, sex, and the Apnea-hypopnea index were predictors of arrhythmia in this sample.     

Dehydroepiandrosterone (DHEA) improves pulmonary hypertension in chronic obstructive pulmonary disease (COPD): a pilot study

ObjectivesIt was previously shown that dehydroepiandrosterone (DHEA) reverses chronic hypoxia-induced pulmonary hypertension (PH) in rats, but whether DHEA can improve the clinical and hemodynamic status of patients with PH associated to chronic obstructive pulmonary disease (PH-COPD) has not been studied whereas it is a very severe poorly treated disease.Patients and methodsEight patients with PH-COPD were treated with DHEA (200 mg daily orally) for 3 months. The primary end-point was the change in the 6-minute walk test (6-MWT) distance. Secondary end-points included pulmonary hemodynamics, lung function tests and tolerance of treatment.ResultsThe 6-MWT increased in all cases, from 333 m (median [IQR]) (257; 378) to 390 m (362; 440) (P < 0.05). Mean pulmonary artery pressure decreased from 26 mmHg (25; 27) to 21.5 mmHg (20; 25) (P < 0.05) and pulmonary vascular resistance from 4.2 UI (3.5; 4.4) to 2.6 UI (2.5; 3.8) (P < 0.05). The carbon monoxide diffusing capacity of the lung (DLCO % predicted) increased significantly from 27.4% (20.1; 29.3) to 36.4% (14.6; 39.6) (P < 0.05). DHEA treatment did not change respiratory parameters of gas exchange and the 200 mg per day of DHEA used was perfectly tolerated with no side effect reported.ConclusionDHEA treatment significantly improves 6-MWT distance, pulmonary hemodynamics and DLCO of patients with PH-COPD, without worsening gas exchange, as do other pharmacological treatments of PH (trial registration NCT00581087).     

Antigen stored in dendritic cells after macropinocytosis is released unprocessed from late endosomes to target B cells

B lymphocytes can be triggered in lymph nodes by nonopsonized antigens (Ag), potentially in their native form. However, the mechanisms that promote encounter of B lymphocytes with unprocessed antigens in lymph nodes are still elusive. We show here that antigens are detected in B cells in the draining lymph nodes of mice injected with live, but not fixed, dendritic cells (DCs) loaded with antigens. This highlights active processes in DCs to promote Ag transfer to B lymphocytes. In addition, antigen-loaded DCs found in the draining lymph node were CD103+. Using 3 different model Ag, we then show that immature DCs efficiently take up Ag by macropinocytosis and store the internalized material in late endocytic compartments. We find that DCs have a unique ability to release antigens from these compartments in the extracellular medium, which is controlled by Rab27. B cells take up the regurgitated Ag and the chemokine CXCL13, essential to attract B cells in lymph nodes, enhances this transfer. Our results reveal a unique property of DCs to regurgitate unprocessed Ag that could play an important role in B-cell activation.     

Syndrome post-arrêt cardiaque : aspects physiopathologiques,cliniques et thérapeutiques

Objective

This review aims at providing an update on post-cardiac arrest syndrome, from pathophysiology to treatment.

Data sources

Medline database.

Data extraction

All data on pathophysiology, clinical manifestations and therapeutic management, with focus on the publications of the 5 last years.

Data synthesis

Care of the patients after cardiac arrest is a medical challenge, in face of “post-cardiac arrest syndrome”, which culminates into multi-organ failure. This syndrome mimics sepsis-related dysfunctions, with all clinical and biological manifestations related to the phenomenon of global ischemia-reperfusion. Acute cardiocirculatory dysfunction is usually controlled through pharmacological and mechanical support. Meanwhile, as a majority of cardiac arrest is related to myocardial infarction, early angiographic exploration should then be discussed when there is no obvious extracardiac cause, percutaneous coronary revascularization being associated with improved short and long-term prognosis. Therapeutic hypothermia is the cornerstone of neuroprotective armamentarium, beyond hemodynamic stabilization and metabolic maintenance.

Conclusion

If ongoing evaluations should shed light on potential efficiency of new therapeutic drugs, a multidisciplinary approach of the post-cardiac arrest syndrome in expertise centre is essential.     

Decrease in cerebellar blood flow in patients with Friedreich’s ataxia: A TC-HMPAO SPECT study of three cases

Abstract

Three cases of Friedreich’s ataxia were submitted to diverse neuroradiological procedures in order to determine the extent of atrophic processes in the central nervous system. All patients underwent computerized-tomography scan, Magnetic Resonance Imaging, and HMPA-single Photon emission computerized tomography studies, focusing in cerebellar lobes. A slight atrophy was observed in the vermis and the cerebellar lobes with CT scan and MRI. In contrast a significant decrease in cerebellar blood flow was shown by TC-HMPAE SPECT study. The significance of these findings in understanding physiopathological mechanisms in Friedreich’s ataxia is discussed. [Neurol Res 1994; 16: 342-344]