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Gender identity is the main topic within the field of anthropology of gender: it is an identity with a polysemic character. The present paper focuses on the identity of social gender, since gender is a field of negotiation and a criterion for the analysis of culture. Social gender is a result of social-cultural constructions, established through the repetition of stereotypical dance acts. In this context, dance functions as a symbol, and its study allows the understanding of social structures, and therefore, the understanding of gender identity. Every dance event can be approached as a conceptual field, in which participants act according to gender standards and experience themselves as gender subjects.
The aim of this paper is to show the gender social structures and relations within dance and dance practices, as they are imprinted on the mountain and lowland areas of Karditsa (Thessaly), in combination with the predominant social structures. For this purpose, we made use of the theoretical model of Hanna, where dance and dance executions are fields of negotiation of gender identity, as well as Cowan’ s model, according to which social gender can be studied within the context of “dance events.”
Through the analysis of these “events,” several discrepancies in social structures and relations were detected between the lowland and mountain communities. These differences are based on dance occasions, and participation or lack of participation of both genders in these occasions, according to dance norms, dance order, and dance types. The above discrepancies constitute gender diversity among lowland and mountain communities, as a result of local social structures and the performative acts.
Systemic right ventricular systolic dysfunction is common late after atrial switch surgery for transposition of the great arteries. Total isovolumic time is the time that the ventricle is neither ejecting nor filling and is calculated without relying on geometric assumptions. We assessed resting total isovolumic time in this population and its relationship to exercise capacity.
A total of 40 adult patients with transposition of the great arteries after atrial switch – and 10 healthy controls – underwent transthoracic echocardiography and cardiopulmonary exercise testing from January, 2006 to January, 2009. Resting total isovolumic time was measured in seconds per minute: 60 minus total ejection time plus total filling time.
The mean age was 31.6 plus or minus 7.6 years, and 38.0% were men. There were 16 patients (40%) who had more than or equal to moderate systolic dysfunction of the right ventricle. Intra- and inter-observer agreement was good for total isovolumic time, which was significantly prolonged in patients compared with controls (12.0 plus or minus 3.9 seconds per minute versus 6.0 plus or minus 1.8 seconds per minute, p-value less than 0.001) and correlated significantly with peak oxygen consumption (r equals minus 0.63, p-value less than 0.001). The correlation strengthened (r equals minus 0.73, p-value less than 0.001) after excluding seven patients with exercise-induced cyanosis. No relationship was found between exercise capacity and right ventricular ejection fraction or long-axis amplitude.
Resting isovolumic time is prolonged after atrial switch for patients with transposition of the great arteries. It is highly reproducible and relates well to exercise capacity.
Inappropriate heart rate response to exercise – chronotropic incompetence – and exercise intolerance are common in patients with a systemic right ventricle. We aimed to assess the relationship between heart rate increase, oxygen consumption, and timing of the right ventricular cardiac cycle in this cohort.
We prospectively studied nine patients with systemic right ventricles and pre-existing pacemakers using Doppler-echocardiography and treadmill exercise testing. Echocardiography was performed at increasing heart rates. Exercise tests were performed with baseline pacemaker settings and with optimised heart rate response in random order. In addition, eight age- and gender-matched controls underwent exercise testing using a similar exercise protocol.
Patients with a systemic right ventricle had significantly lower peak oxygen consumption compared to controls – 12.6 plus or minus 6.8 versus 31.4 plus or minus 6.6 metres per kilogram per minute (p = 0.0006) – at baseline and active pacemaker reprogramming failed to increase peak oxygen consumption in this cohort – 12.6 plus or minus 6.8 versus 12.4 plus or minus 4.9 millilitres per kilogram per minute (p = NS) at baseline and with reprogramming, respectively. We found not only a marked increase in total isovolumic time but also a significant reduction in total filling time and the aortic velocity time integral, p-value is less than 0.001 for all, at higher heart rates compared to baseline conditions.
This study suggests that despite chronotropic incompetence at baseline, rate-responsive pacing does not improve exercise capacity in patients with a systemic right ventricle. It further indicates that high heart rates may be detrimental in these patients by reducing diastolic filling and stroke volume. These findings may have clinical implications when considering implantation of a permanent pacemaker in this cohort.
Atrial septostomy is performed in patients with severe pulmonary arterial hypertension, and has been shown to improve symptoms, quality of life and survival. Despite recognized clinical benefits, the underlying pathophysiologic mechanisms are poorly understood. We aimed to assess the effects of right-to-left shunting on arterial delivery of oxygen, mixed venous content of oxygen, and systemic cardiac output in patients with pulmonary arterial hypertension and a fixed flow of blood to the lungs. We formulated equations defining the mandatory relationship between physiologic variables and delivery of oxygen in patients with right-to-left shunting. Using calculus and computer modelling, we considered the simultaneous effects of right-to-left shunting on physiologies with different pulmonary flows, total metabolic rates, and capacities for carrying oxygen. Our study indicates that, when the flow of blood to the lungs is fixed, increasing right-to-left shunting improves systemic cardiac output, arterial blood pressure, and arterial delivery of oxygen. In contrast, the mixed venous content of oxygen, which mirrors the average state of tissue oxygenation, remains unchanged. Our model suggests that increasing the volume of right-to-left shunting cannot compensate for right ventricular failure. Atrial septostomy in the setting of pulmonary arterial hypertension, therefore, increases the arterial delivery of oxygen, but the mixed systemic saturation of oxygen, arguably the most important index of tissue oxygenation, stays constant. Our data suggest that the clinically observed beneficial effects of atrial septostomy are the result of improved flow of blood rather than augmented tissue oxygenation, provided that right ventricular function is adequate.
Vascular rings are rare vascular congenital anomalies causing oesophageal and tracheal compression. An aortoesophageal fistula is a devastating, in part iatrogenic, complication of vascular rings. It is seen with increasing frequency, and can be misleading, since differential diagnosis with other causes of haematemesis and melaena is often difficult, especially in infants. We report two infants with aortoesophageal fistulas secondary to double aortic arches forming a vascular ring. In both, the diagnosis was missed, and massive haemorrhage led to death. In both cases, the fissuration on the oesophageal and aortic sides of the fistula had sharp edges, highly suggestive of an iatrogenic laceration caused by manipulation of nasogastric tubes. The key for the diagnosis of vascular rings is, therefore, clinical suspicion and awareness of this condition. Prompt identification in infants with stridor, wheezing, or respiratory distress can prevent prolonged intubation, thus avoiding the formation of an aortoesophageal fistula and hopefully preventing a fatal outcome.
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