Acute and chronic electrical activation of baroreceptor afferents in awake and anesthetized subjects

Electrical stimulation of baroreceptor afferents was used in the 1960's in several species, including human beings, for the treatment of refractory hypertension. This approach bypasses the site of baroreceptor mechanosensory transduction. Chronic electrical stimulation of arterial baroreceptors, particularly of the carotid sinus nerve (Hering's nerve), was proposed as an ultimate effort to treat refractory hypertension and angina pectoris due to the limited nature of pharmacological therapy available at that time. Nevertheless, this approach was abandoned in the early 1970's due to technical limitations of implantable devices and to the development of better-tolerated antihypertensive medications. More recently, our laboratory developed the technique of electrical stimulation of the aortic depressor nerve in conscious rats, enabling access to hemodynamic responses without the undesirable effect of anesthesia. In addition, electrical stimulation of the aortic depressor nerve allows assessment of the hemodynamic responses and the sympathovagal balance of the heart in hypertensive rats, which exhibit a well-known decrease in baroreflex sensitivity, usually attributed to baroreceptor ending dysfunction. Recently, there has been renewed interest in using electrical stimulation of the carotid sinus, but not the carotid sinus nerve, to lower blood pressure in conscious hypertensive dogs as well as in hypertensive patients. Notably, previous undesirable technical outcomes associated with electrical stimulation of the carotid sinus nerve observed in the 1960's and 1970's have been overcome. Furthermore, promising data have been recently reported from clinical trials that evaluated the efficacy of carotid sinus stimulation in hypertensive patients with drug resistant hypertension.FAPESPCNPqCoordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES

Assessment of Entrepreneurial Competencies and Intentions of College of Agriculture Students in Laguna State Polytechnic University–Siniloan Campus

Entrepreneurship is one of the programs that must be promoted considering students of this program could become future entrepreneurs. This study focused on assessing entrepreneurial competencies and intentions of 297 students of the College of Agriculture in Laguna State Polytechnic University–Siniloan Campus, particularly those studying agribusiness, agriculture, agricultural education, and agricultural technology. The respondents were interviewed about their entrepreneurial plans or intentions, personal entrepreneurial competencies, and their school’s educational and administrative support. Results show that students indicated a strong desire to pursue entrepreneurship after finishing their degree. Sociodemographic profile had a great impact on their entrepreneurial intentions. With regards to their personal entrepreneurial competency level, the students were found to be strong in terms of information seeking, systematic planning, and monitoring, goal setting, and opportunity seeking, but were found weak when it comes to demand for efficiency and quality, self-confidence, and risk-taking ability. Meanwhile, the school’s educational and administrative support system were viewed as positive reinforcement towards the students’ entrepreneurial intentions. The study recommends that school administration requires more entrepreneurial activities so as to harness students’ capabilities as entrepreneurs among other things. Likewise, it is also suggested that faculties students are required more activities that will hone their entrepreneurial skills as well as help inculcate leadership and teamwork in them

Ovariectomy does not affect the cardiac sympathovagal balance of female SHR but estradiol does

The low incidence of cardiovascular diseases, including hypertension, in premenopausal women has led to the conclusion that ovarian hormones may have a protective effect on the cardiovascular system. We evaluated the effects of ovariectomy and/or estradiol on sympathovagal balance and heart rate variability (HRV) in female spontaneously hypertensive rats (SHR) with tachycardia and compared them to Wistar rats (12 weeks old; N = 8-12). Ovariectomy (OVX) and/or estradiol (10 µg/kg) did not affect basal arterial pressure in either rat strain, but estradiol increased basal heart rate (HR) in OVX SHR (454 ± 18 vs 377 ± 9 bpm). HR changes elicited by methylatropine and propranolol were used to evaluate the sympathovagal balance. Ovariectomy did not affect the cardiac sympathovagal balance of any group, while estradiol increased sympathetic tone in OVX SHR (120 ± 8 vs 56 ± 10 bpm) and sham-operated Wistar rats (57 ± 7 vs 28 ± 4 bpm), and decreased the parasympathetic tone only in OVX SHR (26 ± 7 vs 37 ± 5 bpm). HRV was studied in the frequency domain (Fast Fourier Transformation). Spectra of HR series were examined at low frequency (LF: 0.2-0.75 Hz) and high frequency (HF: 0.75-3 Hz) bands. The power of LF, as well as the LF/HF ratio, was not affected by ovariectomy, but estradiol increased both LF (29 ± 4 vs 18 ± 3 nu in Wistar sham-operated, 26 ± 5 vs 15 ± 3 nu in Wistar OVX, 50 ± 3 vs 38 ± 4 nu in SHR sham-operated, and 51 ± 3 vs 42 ± 3 nu in SHR OVX) and LF/HF (0.48 ± 0.08 vs 0.23 ± 0.03 nu in Wistar sham-operated, 0.41 ± 0.14 vs 0.19 ± 0.05 nu in Wistar OVX, 0.98 ± 0.11 vs 0.63 ± 0.11 nu in SHR sham-operated, and 1.10 ± 0.11 vs 0.78 ± 0.1 nu in SHR OVX). Thus, we suggest that ovariectomy did not affect the cardiac sympathovagal balance of SHR or Wistar rats, while estradiol increased the sympathetic modulation of HR

Myositis ossificans in the diabetic foot: A review of the literature with an illustrative case series

We report the first cases (to our knowledge) of myositis ossificans (MO) in the ‘diabetic foot’

Bacterial sinusitis and its frightening complications: subdural empyema and Lemierre syndrome

The symptoms of a previously healthy 14-year-old female with an initial history of tooth pain and swelling of the left maxillary evolved to a progressive headache and altered neurological findings characterized by auditory hallucinations, sleep disturbances, and aggressiveness. She was brought to the emergency department after 21 days of the initial symptoms. An initial computed tomography (CT) scan showed frontal subdural empyema with bone erosion. The symptoms continued to evolve to brain herniation 24 hours after admission. A second CT scan showed a left internal jugular vein thrombosis. The outcome was unfavorable and the patient died on the second day after admission. The autopsy findings depicted rarefaction of the cranial bone at the left side of the frontal sinus, and overt meningitis. The severe infection was further complicated by thrombophlebitis of the left internal jugular vein up to the superior vena cava with septic embolization to the lungs, pneumonia, and sepsis. This case report highlights the degree of severity that a trivial infection can reach. The unusual presentation of the sinusitis may have wrongly guided the approach of this unfortunate cas

Inferior petrosal sinus catheterization: technical aspects

OBJETIVO: O cateterismo dos seios petrosos inferiores (SPI) ajuda a diferenciar as formas hipofisária e ectópica na síndrome de Cushing (SC). O objetivo desse trabalho é descrever a técnica empregada em nosso serviço, discutir a solução de dificuldades e verificar o índice de sucesso atingido. CASUÍSTICA E MÉTODO: Foram submetidos a cateterismo bilateral dos SPI 42 pacientes com SC, entre setembro de 2000 e setembro de 2005. As dificuldades para o posicionamento do cateter foram correlacionadas com as soluções empregadas. RESULTADOS: As variações anatômicas, a semelhança entre o SPI e a veia emissária do plexo basilar e a dificuldade de contrastar as estruturas a contrafluxo para localizá-las foram os principais problemas. Foram utilizados cateter pré-moldado, fio-guia semicurvo e dirigível, road-maping e venografia por injeção contralateral, além de critérios para diferenciar o SPI da veia emissária. Dos 84 SPI abordados, um apresentava trombose, e dos 83 possíveis, 80 (96,4%) foram cateterizados. Não se observaram complicações. CONCLUSÃO: A cateterização dos SPI pode ser feita na maioria dos pacientes. A identificação da veia emissária do plexo basilar e o uso de flebografia por injeção contralateral melhoraram o desempenho do método.PURPOSE: Inferior petrosal sinus catheterization and sampling for corticotropin dosage helps to differentiate hypophisary and ectopic forms of Cushing syndrome. The aim of this paper is to describe the technique used in inferior petrosal sinus catheterization in our service, emphasizing the solution found for frequent difficulties, and verify the success rate achieved. PATIENTS AND METHODS: Between September/2000 and September/2005, forty-two (eighty-four sinuses) patients were submitted to inferior petrosal sinus sampling. The difficulties for correct catheter positioning were identified and correlated with their solutions. RESULTS: Anatomical variations, similarity between IPS and emissary vein of the basilar plexus and unfavorable flow to the contrastation of the structures (retrograde catheterization) were the main problems. Using pre-shaped catheters, curved, steerable guide-wires, road-maping and venography by contalateral injection, besides criteria to differentiate IPS from the emissary vein. Of the 84 sinuses approached, one was thrombosed, and 80 (96.4%) of 83 possible were selectively catheterized. No clinical complication occurred. CONCLUSION: IPSC can be safe and successfully performed in most cases. The identification of the emissary vein of the basilar plexus and use of venography by contralateral injection, improved the method performance

Da tradução de “Uma revolução conservadora na edição”, de Pierre Bourdieu

Esta tradução do artigo “Une révolution conservatrice dans l’édition”, de Pierre Bourdieu, requer alguns esclarecimentos

Handgrip strength

The basic function of the human hand is the manipulation and grasping of various objects in all daily activities, including work activities. This is greatly influenced by strength and manual dexterity. However age, gender and other contexts such as work or leisure activities could influence strength. Handgrip strength, a measure of maximum voluntary force of the hand, has proved to be reliable and valid as an objective parameter to evaluate the functional integrity of the hand as part of the musculoskeletal system. It correlates highly with strength in other muscular groups and is therefore considered as a good indicator of overall muscular strength and functional stress and could be used as a predictor of physical disability. Handgrip strength assessment is simple and reliable and used commonly by several investigators and health professionals, in different contexts (medical, nutritional, rehabilitation, professional settings, engineering, etc.) and with different purposes (research, diagnostic, assessment, etc.). In clinical and rehabilitation settings is of vital importance in the determination of effectiveness of several interventions and for monitoring evolution of diseases. Various ways (methods, techniques and equipments) of collecting information on grip strength have been reported. This chapter will review basic concepts on handgrip function, methodologies of assessment, contexts of application and correlates, such as physical activity, health or nutritional status. Several populations and reference values as also the relationships between handgrip and clinical status, aging, risk of disability and diseases, will be discussed