Pulmonary cryptococcosis induces chitinase in the rat

<p>Abstract</p> <p>Background</p> <p>We previously demonstrated that chronic pulmonary infection with <it>Cryptococcus neoformans </it>results in enhanced allergic inflammation and airway hyperreactivity in a rat model. Because the cell wall of <it>C. neoformans </it>consists of chitin, and since acidic mammalian chitinase (AMCase) has recently been implicated as a novel mediator of asthma, we sought to determine whether such infection induces chitinase activity and expression of AMCase in the rat.</p> <p>Methods</p> <p>We utilized a previously-established model of chronic <it>C. neoformans </it>pulmonary infection in the rat to analyze the activity, expression and localization of AMCase.</p> <p>Results</p> <p>Our studies indicate that intratracheal inoculation of <it>C. neoformans </it>induces chitinase activity within the lung and bronchoalveolar lavage fluid of infected rats. Chitinase activity is also elicited by pulmonary infection with other fungi (e.g. <it>C. albicans</it>), but not by the inoculation of dead organisms. Enhanced chitinase activity reflects increased AMCase expression by airway epithelial cells and alveolar macrophages. Systemic cryptococcosis is not associated with increased pulmonary chitinase activity or AMCase expression.</p> <p>Conclusion</p> <p>Our findings indicate a possible link between respiratory fungal infections, including <it>C. neoformans</it>, and asthma through the induction of AMCase.</p

Dentoalveolar comparative study between removable and fixed cribs, associated to chincup, in anterior open bite treatment

OBJECTIVE: The aim of this prospective study was to compare the dentoalveolar effects produced by two types of palatal crib, removable (Rpc+C) and fixed (Fpc+C), combined with chincup in growing patients with anterior open bite. MATERIAL AND METHODS: Each group comprised 30 patients, in the mixed dentition phase, with similar cephalometric characteristics and skeletal ages. Group 1 (Rpc+C) presented initial mean age of 8.3 years and mean anterior open bite of 4.0 mm. Group 2 (Fpc+C) presented initial mean age of 8.54 years and mean anterior open bite of 4.3 mm. The evaluation period comprised 12 months between initial (T1) and second lateral radiograph (T2). The T2-T1 changes were compared cephalometrically in the 2 groups using the non-paired t-test. RESULTS: Vertical changes in the posterior dentoalveolar region were similar between the groups (about 1 mm) and no significant differences were found in molar mesialization. The Fpc+C group had in average 1.6 mm more improvement of the overbite as a result of greater maxillary incisor extrusion (1.3 mm). Patients in this group also presented less lingual tipping of maxillary incisors and more mandibular incisors uprighting. CONCLUSIONS: The Fpc+C combination was more efficient in the correction of the negative overbite mainly due to greater extrusion of the maxillary incisors. However, the Rpc+C appliance promoted better upper and lower incisor inclination, resulting in a more adequate overjet

Exercise-induced intra-ventricular gradients as a frequent potential cause of myocardial ischemia in cardiac syndrome X patients

<p>Abstract</p> <p>Background</p> <p>The development of intra-ventricular gradients (IVG) during dobutamine or exercise stress is not infrequent, and can be associated to symptoms during stress.</p> <p>The purpose of this study was to assess the occurrence of IVG during exercise stress echocardiography in cardiac syndrome X patients.</p> <p>Methods</p> <p>We prospectively evaluated 91 patients (pts) mean aged 51 ± 12 years (age ranged 20 to 75 years old), 44 of whom were women. All pts had angina, positive exercise ECG treadmill testing, normal rest echocardiogram and no coronary artery disease on coronary angiogram (cardiac X syndrome). After complete Doppler echocardiographic evaluation with determination of left ventricular outflow tract index (LVOTi), relative left ventricular wall thickness (RLVWT) and left ventricular end-diastolic volume index (LVDVi), all patients underwent stress echocardiography with two-dimensional and Doppler echographic evaluation during and after treadmill exercise.</p> <p>Results</p> <p>For analysis purpose patients were divided in 2 groups, according to the development of IVG. Doppler evidence of IVG was found in 33 (36%) of the patients (Group A), with mean age 47 ± 14 years old (age ranged 20 to 72 years) and with a mean end-systolic peak gradient of 86 ± 34 mmHg (ranging from 30 to 165 mmHg). The IVG development was accompanied by SAM of the mitral valve in 23 pts. Three of these pts experienced symptomatic hypotension. Ten were women (30% pts). 58 pts in group B, 34 of whom were women (59%) (p = 0,01 vs group A), mean aged 53,5 ± 10,9 years old (age ranged 34 to 75 years) (p = 0,03 vs group A), did not develop IVG. LVOTi was 10,29 ± 0,9 mm/m²in group A and 11,4 ± 1 mm/m²in group B (p < 0,000); RLVWT was 0,36 ± 0,068 in group A and 0,33 ± 0,046 in group B (p < 0,01); LVDVi was 44,8 ± 10 ml/m²in group A and 56 ± 11,6 ml/m²in group B (p = 0,000).</p> <p>Conclusion</p> <p>1. A significant number of patients with cardiac X syndrome developed IVG during upright exercise in treadmill. These pts (group A) are mainly males and younger than those who did not develop IVG.</p> <p>2. The development of IVG and mitral valve SAM on exertion seems to be associated with ST segment downsloping during stress testing in patients without epicardial coronary disease.</p> <p>3. The development of IVG and mitral valve SAM seems to be associated with lower LVOTi, lower LVDVi and higher RLVWT.</p

Male urine signals social rank in the Mozambique tilapia (Oreochromis mossambicus)

<p>Abstract</p> <p>Background</p> <p>The urine of freshwater fish species investigated so far acts as a vehicle for reproductive pheromones affecting the behaviour and physiology of the opposite sex. However, the role of urinary pheromones in intra-sexual competition has received less attention. This is particularly relevant in lek-breeding species, such as the Mozambique tilapia (<it>Oreochromis mossambicus</it>), where males establish dominance hierarchies and there is the possibility for chemical communication in the modulation of aggression among males. To investigate whether males use urine during aggressive interactions, we measured urination frequency of dye-injected males during paired interactions between size-matched males. Furthermore, we assessed urinary volume stored in the bladder of males in a stable social hierarchy and the olfactory potency of their urine by recording of the electro-olfactogram.</p> <p>Results</p> <p>Males released urine in pulses of short duration (about one second) and markedly increased urination frequency during aggressive behaviour, but did not release urine whilst submissive. In the stable hierarchy, subordinate males stored less urine than males of higher social rank; the olfactory potency of the urine was positively correlated with the rank of the male donor.</p> <p>Conclusion</p> <p>Dominant males store urine and use it as a vehicle for odorants actively released during aggressive disputes. The olfactory potency of the urine is positively correlated with the social status of the male. We suggest that males actively advertise their dominant status through urinary odorants which may act as a 'dominance' pheromone to modulate aggression in rivals, thereby contributing to social stability within the lek.</p