Analysis of Anatomical Characteristics and Morphometric Aspects of Infraorbital and Accessory Infraorbital Foramina.

OBJECTIVE: This study aimed to perform a morphological and morphometric study of the characteristics of the infraorbital foramen (IOF) and accessory infraorbital foramen (AIOF) in Brazilian skulls. METHODS: A sample calculation determined a total of 94 human skulls to be evaluated by a trained examiner for number, shape, diameters, and location of IOF in relation to anatomical landmarks. Number, size, shape, diameters, location, orientation, position, and distances in relation to anatomical landmarks were evaluated for the AIOF. Descriptive analysis, paired t test, Wilcoxon test, Pearson and Spearman correlations were used. RESULTS: A total of 188 IOFs and 48 AIOFs were found. Circular outline was the predominant shape for both IOFs and AIOFs. Infraorbital foramens presented in left sides had a significantly greater transverse diameter and distance from medial margin of the orbit when compared with IOFs located on the right sides (P <0.001). Accessory infraorbital foramens were most frequently found on the left sides of the skulls and had a superomedial position in relation to the IOFs. Accessory infraorbital foramens located on right sides had a significantly greater distance to anterior nasal spine when compared with AIOFs located on the left sides (P <0.001). CONCLUSIONS: The results of this solid methodology-based study can help guide surgeons in accurately locating the IOF and AIOF, and consequently, their neurovascular bundles to perform safe procedures during maxillofacial interventions.

Cardioprotective effects of diminazene aceturate in pressure-overloaded rat hearts.

AIMS: Angiotensin-converting enzyme 2 (ACE2) is a key modulator of the renin-angiotensin system. Recent studies have shown that diminazene aceturate (DIZE) acts as an ACE2 activator. The aim of this study was to evaluate the cardiac effects of chronic treatment with DIZE in pressure-overloaded rats. MAIN METHODS: Male Wistar rats were divided into 4 groups: (1) sham; (2) aortic banded rats (AB); (3) AB+DIZE (1mg/kg, gavage); and (4) AB+DIZE+A-779 (120µg/day, osmotic mini-pumps). Cardiac hypertrophy was evaluated by ventricular mass index and myocyte cross-sectional area. mRNA expression of atrial natriuretic peptide (ANP), B-type natriuretic peptide (BNP) and transforming growth factor beta 1 (TGF-ß) was quantified by RT-PCR. Cardiac function was assessed according to the Langendorff technique. The ACE2 and Mas protein expression was examined by western blot analysis. KEY FINDINGS: DIZE treatment prevented the cardiomyocyte hypertrophy promoted by AB and A-779 inhibited this effect. Also, DIZE induced the expression of ANP and BNP mRNA in cardiac tissue from AB rats and attenuated the impairment in left ventricular end-systolic pressure and left ventricular developed pressure, +dP/dt and -dP/dt caused by AB. These effects were blocked by A-779. Moreover, DIZE prevented the increase in the expression of TGF-ß mRNA in AB hearts, but it did not change the ACE2 and Mas protein expression. SIGNIFICANCE: These results showed that DIZE was efficient in preventing the cardiomyocyte hypertrophy and attenuated the left ventricular contractile impairment induced by pressure overload. However, further studies are necessary to confirm whether these effects were due to ACE2 activation.

Cardiac responses of rats submitted to postnatal protein restriction.

Undernutrition during critical stages of development and childhood has important effects on cardiovascular homeostasis. The present study was undertaken to evaluate the in vivo and ex vivo cardiac function of rats submitted to postnatal protein restriction. Male Wistar rats (28 days old) were fed a regular (20%) or low-protein (6%) diet over 5 weeks. After this period, cardiac function was analyzed by echocardiography and isolated heart preparation. Furthermore, the density of cardiac noradrenergic fibers and hematological profile were evaluated. We found that malnourished rats exhibited elevated arterial blood pressure, increased fractional shortening (echocardiography), increased systolic tension, increased ±dT/dt (isolated heart technique), impaired diastolic function characterized by a slight increase in the left ventricular end-diastolic diameter (echocardiography) and decreased diastolic tension (isolated heart technique), and cardiac hypertrophy evidenced by augmentation of the posterior left ventricular wall and discrete hematological changes. In addition, malnourished rats exhibited increased noradrenergic fiber density in their hearts (0.08% ± 0.02% area in control rats vs. 0.17% ± 0.03% area in malnourished rats). Our current data demonstrate that postnatal protein restriction causes cardiac adaptation characterized by an early overworking heart. This is at least in part mediated by an increase in the efferent sympathetic fibers to the heart. These findings provide important information for efforts to prevent and manage the consequences of undernutrition in the human population.