Effects of environmental factors, age and genotype on sperm production and semen quality in Bos indicus and Bos taurus AI bulls in Brazil

The effects of ambient temperature and humidity, month, age and genotype on sperm production and semen quality in AI bulls in Brazil were evaluated. Data from two consecutive years were analyzed separately. Seven Bos indicus and 11 Bos taurus bulls from one artificial insemination (AI) center were evaluated in Year 1 and 24 B. indicus and 16 B. taurus bulls from three AI centers were evaluated in Year 2. Ambient temperature and humidity did not significantly affect sperm production and semen quality, probably because there was little variation in these variables. Month accounted for less than 2% of the variation in sperm production and semen quality. Increased bull age was associated with decreased sperm motility (P < 0.10) and increased minor sperm defects (P < 0.001) in Year 1. B. indicus bulls had greater (P < 0.005) sperm concentration than B. taurus bulls in both years (1.7 x 10(9)/ml versus 1.2 x 10(9)/ml in Year 1 and 1.6 x 10(9)/ml versus 1.2 x 10(9)/ml in Year 2, respectively). Ejaculate volume was not significantly affected by genotype in Year 1 (6.6 ml versus 6.9 ml in B. indicus and B. taurus bulls, respectively), but B. indicus bulls had greater (P < 0.05) total (11.4 x 10(9) versus 8.2 x 10(9)) and viable (6.7 x 10(9) versus 4.9 x 10(9)) numbers of spermatozoa in the ejaculate than B. taurus bulls. In Year 2, B. taurus bulls had greater (P < 0.05) ejaculate volume than B. indicus bulls (8.2 ml versus 6.7 ml, respectively) and total and viable number of spermatozoa in the ejaculate were not significantly different between genotypes (10.3 x 10(9) versus 9.1 x 10(9) and 6.1 x 10(9) versus 5.4 x 10(9) in B. indicus and B. taurus bulls, respectively). Sperm motility was not significantly affected by genotype (mean, 59%). In Year 1, B. indicus bulls tended (P < 0.10) to have more major sperm defects and had more (P < 0.05) total sperm defects than B. taurus bulls (11.8% versus 8.7% and 13.6% versus 10.0%, respectively). In Year 2, B. indicus bulls tended (P < 0.10) to have more total sperm defects than B. taurus bulls (16.2% versus 13.3%, respectively). In conclusion, neither ambient temperature and humidity nor month (season) significantly affected sperm production and semen quality. B. indicus bulls had significantly greater sperm concentration and B. taurus bulls had significantly fewer morphologically defective spermatozoa. (C) 2002 Elsevier B.V. B.V. All rights reserved.

Postsurgical stability of counterclockwise maxillomandibular advancement surgery: Affect of articular disc repositioning

Purpose: This study evaluated the affect of disc displacement and articular disc repositioning on stability after surgical counterclockwise rotation and advancement of the maxillomandibular complex.Patients and Methods: A total of 72 patients (59 females, 13 males), with an average age of 30 years (range, 15 to 60 years) were evaluated. The patients were divided into 3 groups. Group 1 (G1; n = 21), with healthy temporomandibular joints (TMJs), underwent double jaw surgery only. Group 2 (G2; n = 35), with articular disc dislocation, underwent articular disc repositioning using the Mitek anchor (Mitek Surgical Products, Westwood, MA) technique concomitantly with orthognathic surgery. Group 3 (G3; n = 16), with articular disc dislocation, underwent orthognathic surgery only. Average postsurgical follow-up was 31 months. Each patient's lateral cephalograms were traced, digitized twice, and averaged to estimate surgical changes and postsurgical stability.Results: After surgery, the occlusal plane angle was decreased significantly in all 3 groups: by -6.3 +/- -15.0 degrees in G1, by -9.6 +/- 4.8 degrees in G2, and by -7.1 +/- 4.8 degrees in G3. The maxillomandibular complex was advanced and rotated counterclockwise similarly in all 3 groups, with advancement at the menton of 12.4 +/- 5.5 mm in G1, 13.5 +/- 4.3 mm in G2, and 13.6 +/- 5.0 mm in G3; advancement at the B point of 9.5 +/- 4.9 mm in G1, 10.2 +/- 3.7 mm in G2, and 10.8 +/- 3.7 mm in G3; and advancement at the lower incisor edge of 7.1 +/- 4.6 mm in G1, 6.6 +/- 3.2 mm in G2, and 7.9 +/- 3.0 mm in G3. Postsurgery, the occlusal plane angle increased in G3 (2.6 +/- 3.8 degrees; 37% relapse rate) but remained stable in G1 and G2. Postsurgical mandibular changes in the horizontal direction demonstrated a significant relapse in G3 at the menton (-3.8 +/- 4.1 mm; 28%), the B point (-3.0 +/- 3.4 mm; 28%), and the lower incisor edge (-2.3 +/- 2.1 mm; 34%) but remained stable in G1 and G2.Conclusions: Maxillomandibular advancement with counterclockwise rotation of the occlusal plane is a stable procedure for patients with healthy TMJs and for patients undergoing simultaneous TMJ disc repositioning using the Mitek anchor technique. Those patients with preoperative TMJ articular disc displacement who underwent double-jaw surgery and no TMJ intervention experienced significant relapse. (C) 2008 American Association of Oral and Maxillofacial Surgeons.

Central blockade of nitric oxide synthesis reduces moxonidine-induced hypotension

1 Nitric oxide (NO) and alpha(2)-adrenoceptor and imidazoline agonists such as moxonidine may act centrally to inhibit sympathetic activity and decrease arterial pressure.2 In the present study, we investigated the effects of pretreatment with L-NAME ( NO synthesis inhibitor), injected into the 4th ventricle (4th V) or intravenously (i.v.), on the hypotension, bradycardia and vasodilatation induced by moxonidine injected into the 4th V in normotensive rats.3 Male Wistar rats with a stainless steel cannula implanted into the 4th V and anaesthetized with urethane were used. Blood flows were recorded by use of miniature pulsed Doppler flow probes implanted around the renal, superior mesenteric and low abdominal aorta.4 Moxonidine (20 nmol), injected into the 4th V, reduced the mean arterial pressure (-42+/-3 mmHg), heart rate (-22+/-7 bpm) and renal (-62+/-15%), mesenteric (-41+/-8%) and hindquarter (-50+/-8%) vascular resistances.5 Pretreatment with L-NAME (10 nmol into the 4th V) almost abolished central moxonidine-induced hypotension (-10+/-3 mmHg) and renal (-10+/-4%), mesenteric (-11+/-4%) and hindquarter (-13+/-6%) vascular resistance reduction, but did not affect the bradycardia (-18+/-8 bpm).6 the results indicate that central NO mechanisms are involved in the vasodilatation and hypotension, but not in the bradycardia, induced by central moxonidine in normotensive rats. British Journal of Pharmacology (2004).

AV3V lesions reduce the pressor response to L-glutamate into the RVLM

Neurons from the rostral ventrolateral medulla (RVLM) directly activate sympathetic preganglionic neurons in the spinal cord. Hypertensive responses and sympathetic activation produced by different stimuli are strongly affected by lesions of the preoptic periventricular tissue surrounding the anteroventral third ventricle (AV3V region). Therefore, in the present study, we investigated the effects of acute (1 day) and chronic (IS days) electrolytic lesions of the AV3V region on the pressor responses produced by injections of the excitatory amino acid L-glutamate into the RVLM of unanesthetized rats. Male Holtzman rats with sham or electrolytic AV3V lesions and a stainless steel cannula. implanted into the RVLM were used. The pressor responses produced by injections of L-glutamate (1, 5 and 10 nmol/100 nl) into the RVLM were reduced 1 day (9 +/- 4, 39 +/- 6 and 37 +/- 4 mm Hg, respectively) and 15 days after AV3V lesions (13 +/- 6, 39 +/- 4 and 43 +/- 4 mm Hg, respectively, vs. sham lesions: 29 +/- 3, 50 +/- 2 and 58 +/- 3 mm Hg, respectively). Injections of L-glutamate into the RVLM in sham or AV3V-lesioned rats produced no significant change in the heart rate (HR). Baroreflex bradycardia and tachycardia produced by iv phenylephrine or sodium nitroprusside, respectively, and the pressor and bradycardic responses to chemoreflex activation with iv potassium cyanide were not modified by AV3V lesions. The results suggest that signals from the AV3V region are important for sympathetic activation induced by L-glutamate into the RVLM. (c) 2006 Elsevier B.V. All rights reserved.

Lateral parabrachial nucleus and central amygdala in the control of sodium intake

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

The Effect of Power Bleaching Actived by Several Light Sources on Enamel Microhardness

The purpose of this study was to evaluate the influence of different light sources for in-office bleaching on surface microhardness of human enamel. One hundred and five blocks of third molars were distributed among seven groups. The facial enamel surface of each block was polished and baseline Knoop microhardness of enamel was assessed with a load of 25 g for 5 s. Subsequently, the enamel was treated with 35% hydrogen peroxide bleaching agent and photo-activated with halogen light (group A) during 38 s, LED (group B) during 360 s, and high intensity diode laser (group C) during 4 s. The groups D (38 s), E (360 s), and F (4 s) were treated with the bleaching agent without photo-activated. The control (group G) was only kept in saliva without any treatment. Microhardness was reassessed after 1 day of the bleaching treatment, and after 7 and 21 days storage in artificial saliva. The mean percentage and standard deviation of microhardness in Knoop Hardness Number were: A 97.8 +/- 13.1 KHN; B 95.5 +/- 12.7 KHN; C 84.2 +/- 13.6 KHN; D 128.6 +/- 20.5 KHN; E 133.9 +/- 14.2 KHN; F 123.9 +/- 14.2 KHN; G 129.8 +/- 18.8 KHN. Statistical analysis (p < 0.05; Tukey test) showed that microhardness percentage values were significantly lower in the groups irradiated with light when compared with the non-irradiated groups. Furthermore, the non-irradiated groups showed that saliva was able to enhance the microhardness during the measurement times. The enamel microhardness was decreased when light sources were used during the bleaching process and the artificial saliva was able to increase microhardness when no light was used.

Stress responses of the fish Nile tilapia subjected to electroshock and social stressors

Plasma cortisol and glucose levels were measured in 36 adult Nile tilapia males, Oreochromis niloticus (standard length, mean ± SD, 14.38 ± 1.31 cm), subjected to electroshock and social stressors. Pre-stressor levels were determined 5 days after the adjustment of the fish to the experimental aquaria (1 fish/aquarium). Five days later, the effects of stressors on both cortisol and glucose levels were assessed. The following stressors were imposed for 60 min: pairing with a larger resident animal (social stressor), or a gentle electroshock (AC, 20 V, 15 mA, 100 Hz for 1 min every 4 min). Each stressor was tested in two independent groups, one in which stress was quantified immediately after the end of the 60-min stressor imposition (T60) and the other in which stress was quantified 30 min later (T90). Pre-stressor values for cortisol and glucose were not statistically different between groups. Plasma cortisol levels increased significantly and were of similar magnitude for both electroshock and the social stressor (mean ± SD for basal and final samples were: electroshock T60 = 65.47 ± 15.3, 177.0 ± 30.3; T90 = 54.8 ± 16.0, 196.2 ± 57.8; social stress T60 = 47.1 ± 9.0, 187.6 ± 61.7; T90 = 41.6 ± 8.1, 112.3 ± 26.8, respectively). Plasma glucose levels increased significantly for electroshock at both time points (T60 and T90), but only at T90 for the social stressor. Initial and final mean (± SD) values are: electroshock T60 = 52.5 ± 9.2, 115.0 ± 15.7; T90 = 35.5 ± 1.1, 146.3 ± 13.3; social stress T60 = 54.8 ± 8.8, 84.4 ± 15.0; T90 = 34.5 ± 5.6, 116.3 ± 13.6, respectively. Therefore, electroshock induced an increase in glucose more rapidly than did the social stressor. Furthermore, a significant positive correlation between cortisol and glucose was detected only at T90 for the social stressor. These results indicate that a fish species responds differently to different stressors, thus suggesting specificity of fish stress response to a stressor.

Latitudinal variation in population structure and reproductive pattern of the endemic south american shrimp Artemesia longinaris (Decapoda : Penaeoidea)

Population Structure and reproductive Maturity of females were investigated in the shrimp Artemesia longinaris Bate, 1888 from coastal waters of northern São Paulo State (Brazil. 23 degrees S) and Mar del Plata (Argentina, 38 degrees S) from June 2001 to May 2002. Monthly collections were taken by, commercial shrimp fishing boats equipped with bottom trawl nets. Population parameters from size frequency distributions and size (carapace length = CL) of female reproductive maturity were analyzed and compared front the two sampling areas. Latitudinal trends in reproductive parameters of A. longinaris were shown in overall body size and size of reproductive maturity, both of which were smaller in females from the tropical location than those front the cold-temperate sampling area. Largest females (> 30 turn CL) were collected in Argentina, while Brazilian specimens reached maximum size at 27 nun CL. The smallest Size of female sexual maturity was estimated at 13.6 nun CL in Brazilian samples compared to 22.1 mm CL calculated for those from Argentina. Populations from both regions exhibited a bimodal size distribution in the spring, with the peak at small body size probably corresponding to recent recruits and the peak at larger body, size to reproductive females or shrimps migrating in from deeper waters or other latitudinal regions. In late spring and summer. an intrusion of the cold South Atlantic Coastal Water mass was observed which lowered water temperature and stimulated plankton production. The primary food source for the larvae of a typically cold-temperate species such as A. longinaris. The trend of increasing body size and delay of sexual maturity with increasing latitude appears to be correlated with the decreasing water temperature and increasing plankton productivity at higher latitudes.

Development of an operational substrate for ZapA, a metalloprotease secreted by the bacterium Proteus mirabilis

The protease ZapA, secreted by Proteus mirabilis, has been considered to be a virulence factor of this opportunistic bacterium. The control of its expression requires the use of an appropriate methodology, which until now has not been developed. The present study focused on the replacement of azocasein with fluorogenic substrates, and on the definition of enzyme specificity. Eight fluorogenic substrates were tested, and the peptide Abz-Ala-Phe-Arg-Ser-Ala-Ala-Gln-EDDnp was found to be the most convenient for use as an operational substrate for ZapA. A single peptide bond (Arg-Ser) was cleaved with a Km of 4.6 µM, a k cat of 1.73 s-1, and a catalytic efficiency of 376 (mM s)-1. Another good substrate for ZapA was peptide 6 (Abz-Arg-Pro-Pro-Gly-Phe-Ser-Pro-Phe-Arg-Gln-EDDnp) which was cleaved at a single bond (Phe-Ser) with a Km of 13.6 µM, a k cat of 3.96 s-1 and a catalytic efficiency of 291 (mM s)-1. The properties of the amino acids flanking the scissile bonds were also evaluated, and no clear requirement for the amino acid residue at P1 was found, although the enzyme seems to have a preference for a hydrophobic residue at P2.

IMPROVEMENTS IN METABOLIC and NEUROMUSCULAR FITNESS AFTER 12-WEEK BODYPUMP (R) TRAINING

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Metabolic, ventilatory, and hygric physiology of a South American marsupial, the long-furred woolly mouse opossum

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Pectinase production by a Brazilian thermophilic fungus Thermomucor indicae-seudaticae N31 in solid-state and submerged fermentation

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Microlepidogaster dimorpha, a new species of Hypoptopomatinae (Siluriformes: Loricariidae) from the upper rio Paraná system

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Search for Dark Matter and Large Extra Dimensions in pp Collisions Yielding a Photon and Missing Transverse Energy

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Magnetic field induced lattice effects in a quasi-two-dimensional organic conductor close to the Mott metal-insulator transition

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)