Asymmetric magnetoimpedance in exchange-biased systems.

Magnetic systems with competing anisotropies generally exhibit asymmetry between the maximum amplitudes of the right and left maxima in a magnetoimpedance curve. Small errors in positioning the samples at the experimental setup may also produce such asymmetry. In this work, we present a study on the sources of the asymmetry between magnetoimpedance peaks in systems that present the exchange bias phenomenon, by comparing a phenomenological model to experimental data. A set of samples with different repetitions of the NiFe/FeMn exchange-biased bilayer was used in this study. From the frequency evolution of the asymmetry, together with magnetization curves, we were able to identify the sources for the observed magnetoimpedance asymmetry found on our experimental data.

Relationship between family history of alcohol problems and different clusters of depressive symptoms.

OBJECTIVES: Major depressive disorder (MDD) is a multifactorial syndrome with significant interactions between genetic and environmental factors. This study specifically investigates the association between family history of alcohol problems (FHAP) and family history of depression (FHD), and how these relate to different clusters of depressive symptoms. METHODS: Correlations between FHAP and FHD and different clusters of the Beck Depression Inventory (BDI) were studied. We sampled 333 employees from a general hospital who had been receiving a psychiatric consultation between 2005 and 2012. Analysis of variance (ANOVA) and Analysis of covariance (ANCOVA) models were conducted to explore these correlations. RESULTS: There was a significant positive correlation between FHAP and BDI affective score. This result remained significant even after the adjustment for other variables considered as important factors for MDD, such as gender, age, marital status, education, ethnic group and FHD. More specifically, FHAP was correlated with dissatisfaction and episodes of crying among the affective symptoms. FHAP showed no statistical difference in any of the other clusters score or in the BDI total score. Moreover, as expected, we found a correlation between FHD and BDI total score and Somatic and Cognitive clusters. CONCLUSION: FHAP should be routinely investigated in individuals presenting with depressive symptoms. This is especially important in cases presenting with dissatisfaction and episodes of crying in patients who do not endorse criteria for MDD. Due to study limitations, the findings require replication by neurobiological, epidemiological and clinical studies.

Germination of small tropical seeds has distinct light quality and temperature requirements, depending on microhabitat.

The coexistence of plant species in tropical rainforests is related to specific abiotic resources, varying according to the occurrence microhabitat of each species. Light quality is the main abiotic factor influencing germination of small seeds; however, studies often do not discriminate its effect from that of light irradiance. This study compared specific requirements for seed germination of ten small-seeded species, with restricted occurrence in only one of three contrasting microhabitats: forest understorey, edge of clearings and open areas. Laboratory experiments were carried out to test temperature regime (constant or fluctuating), light quality (R:FR) and light irradiance (PAR), which reproduce high and low conditions commonly found in the microhabitats. Seed germination of all species occurred between 20 and 30 °C, only seeds of open area species were able to germinate at 35 °C and no species required alternating temperatures to germinate. Irrespective of species and microhabitat, a decrease in the R:FR reduced the germination percentage; however, there were differences in the capacity to germinate at low R:FR. The values of R:FR50% were higher for open area and edge species (0.441-0.345) than for understorey species (0.181-0.109), with few exceptions. For all species and most of the tests, germination was not influenced by PAR. Light quality is the most important light signal for germination of small seeds; irradiance has little effect. Our results suggest two distinct patterns of germination for small-seeded species: open area and edge species are light-demanding and require high R:FR to germinate, while understorey species are shade-tolerant and germinate at low R:FR. These differences are responsible for distinct microhabitat occurrence and help to explain the coexistence of species in tropical forests.

Germination, viability and dormancy of 47 species from threatened tropical montane grassland in southeast Brazil: Implications for ex situ conservation.

To mitigate anthropogenic impacts on plant diversity in tropical montane grasslands, one of the most threatened ecosystems in Brazil, it will be essential to develop ex situ conservation strategies to preserve wild species. The lack of basic research on the seed storage behaviour of grassland species may, however, limit their use for reintroduction and restoration projects. We investigated seed storage behaviour at the community level by comparing the effects of cold-low RH (10 °C; 10% RH) and freezing-low RH (20 °C; 10% RH) conditions on seed viability, germination and dormancy of 47 species. Fresh seeds of 43% of the species showed primary dormancy. More than half of the species showed high seed survival responses (viability >60%) under both storage temperatures. Despite a variety of dormancy responses among the different species, the low RH storage conditions tested released dormancy for most species during 12- and 30-month storage times. Multivariate analysis of the best (freezing-low RH, 30 months) storage condition evidenced the formation of five distinct groups, three with species having high conservation potential in seed banks. Although further studies are needed to test dormancy-breaking treatments and improve seed conservation practices, this first approach to assessing seed banking techniques could contribute to demand for locally adapted seeds for ecological restoration projects in tropical montane grasslands.

Sensory, Motor, and Psychosocial Characteristics of Individuals With Chronic Neck Pain: A Case-Control Study.

OBJECTIVE: Given the complex and unclear etiology of neck pain, it is important to understand the differences in central sensitization as well as psychosocial factors in individuals with chronic neck pain and healthy controls. The purpose of this study was to benchmark differences in central sensitization, psychosocial factors, and range of motion between people with nonspecific chronic neck pain and healthy controls and to analyze the correlation between pain intensity, neck disability, and psychosocial factors in people with chronic neck pain. METHODS: Thirty individuals with chronic neck pain and 30 healthy controls were included in this case-control study. Outcome measures were as follows: central sensitization (pressure pain threshold, temporal summation, and conditioned pain modulation), psychosocial factors (depressive symptoms, pain catastrophizing, and quality of life), and active cervical range of motion. RESULTS: People with neck pain had lower local pressure pain threshold, a decrease in conditioned pain modulation, more depressive symptoms, greater pain catastrophizing, lower quality of life, and reduced range of motion for neck rotation when compared with healthy controls. In people with neck pain, moderate correlations were observed between pain intensity and quality of life (ρ = -0.479), disability and pain catastrophizing (ρ = 0.379), and disability and quality of life (ρ = -0.456). CONCLUSIONS: People with neck pain have local hyperalgesia, impaired conditioning pain modulation, depressive symptoms, pain catastrophizing, low quality of life, and reduced active range of motion during neck rotation, which should be taken into account during assessment and treatment. IMPACT: This study shows that important outcomes, such as central sensitization and psychosocial factors, should be considered during assessment and treatment of individuals with nonspecific chronic neck pain. In addition, pain intensity and neck disability are correlated with psychosocial factors.

Supplemental progesterone during early pregnancy exerts divergent responses on embryonic characteristics in sows and gilts.

Progesterone (P4) plays a key role in pregnancy establishment and maintenance; during early pregnancy, P4 stimulates the production and release of uterine secretions necessary for conceptus growth prior to implantation; therefore, exogenous P4 supplementation may improve embryo development. This study evaluated the effects of supplementation during early pregnancy with long-acting injectable progesterone or altrenogest on embryonic characteristics of sows and gilts. Thus, a total of 32 sows and 16 gilts were used. On day 6 of pregnancy sows and gilts were allocated to one of the following groups: non-supplemented; supplemented with 20 mg of altrenogest, orally, from days 6 to 12 of pregnancy; supplemented with 2.15 mg/kg of long-acting injectable progesterone on day 6 of pregnancy. Animals were killed on day 28 of pregnancy, and ovulation rate, embryo survival, embryo weight, crown-to-rump length, uterine glandular epithelium and endometrial vascularization were assessed. Treatments had no effect on pregnancy rate, embryo survival or endometrial vascular density (P > 0.05). Non-supplemented gilts presented larger and heavier embryos compared to gilts from supplemented groups (P < 0.05). Sows in the altrenogest group presented larger and heavier embryos compared to non-supplemented sows and sows supplemented with long-acting injectable progesterone. In conclusion, supplementation of sows and gilts with progestagen from day 6 of pregnancy can be used as a means to improve embryo survival without deleterious effects.

Absence of seminal plasma from sperm-rich fraction decreases boar sperm quality characteristics during the course of liquid storage.

Seminal plasma (SP), the fluid that surrounds the sperm cells, is known to exert substantial influence on sperm physiology. The SP has a pivotal role in sperm function in vivo, and due to its components, it functions in an ambiguous manner in vitro, simultaneously possessing deleterious and beneficial effects. This experiment aimed to describe the differences between the presence or absence of SP from the sperm-rich fraction on some spermatozoa characteristics (kinetics, plasma and acrosome membrane integrity, lipid peroxidation and capacitation-like changes). Furthermore, this experiment focused on distinguishing the effects of SP on the variables evaluated from the effects of centrifugation during SP removal. Total and progressive sperm motility, as well as integrity of plasma and acrosome membranes, were less (P < 0.05) in the absence of SP. Membrane lipid peroxidation (P < 0.05) and sperm membrane stability (P < 0.05) did not differ among treatments. The SP from the sperm-rich fraction is important for the maintenance of adequate structural and functional characteristics of extended liquid boar semen and should be present in seminal doses throughout storage. Furthermore, the detrimental effect on the variables evaluated was caused solely by the absence of SP and not by the process of removal through centrifugation at 500 x g for 10 min.

Quantification of bleeding during dental extraction in patients on dual antiplatelet therapy.

In spite of the possibility of triggering thromboembolic events, many professionals indicate the suspension of antiplatelet agents before dental surgical procedures. The aim of this study was to perform a quantitative assessment of intraoperative bleeding in patients on dual antiplatelet therapy. A case-control study was conducted in patients on dual antiplatelet therapy (APT group) and in patients who did not use these medications (control group). The following examinations were requested: complete blood cell count, blood coagulation tests, and platelet aggregation. The quantity of bleeding was measured intraoperatively by collection of aspirated blood. The mean volume of blood lost during the surgical procedure was 6.10ml in the control group and 16.07ml in the APT group (P=0.002). The mean volume of blood lost per minute was 0.60ml/min in the control group and 1ml/min in the APT group (P=0.001), with local haemostatic methods being sufficient to control the bleeding. There was no postoperative bleeding complication in any case. Patients on dual antiplatelet therapy presented a larger volume of bleeding, but this could be controlled by means of local haemostatic measures. Therefore, there is no need to stop either of the two dual antiplatelet therapy medications before dental extractions.

Quantification of bleeding during dental extraction in patients on dual antiplatelet therapy

In spite of the possibility of triggering thromboembolic events, many professionals indicate the suspension of antiplatelet agents before dental surgical procedures. The aim of this study was to perform a quantitative assessment of intraoperative bleeding in patients on dual antiplatelet therapy. A case-control study was conducted in patients on dual antiplatelet therapy (APT group) and in patients who did not use these medications (control group). The following examinations were requested: complete blood cell count, blood coagulation tests, and platelet aggregation. The quantity of bleeding was measured intraoperatively by collection of aspirated blood. The mean volume of blood lost during the surgical procedure was 6.10ml in the control group and 16.07ml in the APT group (P=0.002). The mean volume of blood lost per minute was 0.60ml/min in the control group and 1ml/min in the APT group (P=0.001)...

Seminal plasma arising from the whole boar sperm-rich fraction increases the stability of sperm membrane after thawing.

Boar spermatozoa arising from the sperm-rich ejaculate fraction are reported to have a more stable plasma membrane and are more resistant to cold shock and premature acrosome reaction than spermatozoa from the whole ejaculate. Furthermore, seminal plasma (SP) can increase the cryotolerance of boar spermatozoa, and in other domestic species, it has the ability to reverse cryopreservation damage. This study aimed to evaluate the effects of boar SP arising from the whole sperm-rich ejaculate fraction (SP-SRF) on the integrity, stability, and peroxidation of sperm membranes after thawing. Each ejaculate ( = 24) was divided among 4 treatments: control (CT), centrifuged and suspended in autologous SP-SRF (CS), centrifuged with withdrawn SP-SRF (CW), and post-thawed SP arising from the whole sperm-rich fraction addition to CW (CWSP). After thawing, all treatments were incubated for 5, 60, and 120 min and were analyzed for membrane integrity, fluidity, and peroxidation by flow cytometer. The absence of SP-SRF increased the lipid disorder ( < 0.05) but had no effect on lipid peroxidation ( > 0.05) or membrane integrity ( > 0.05). However, the increase in lipid disorder by withdrawal of SP-SRF was reversed by SP-SRF addition ( < 0.05) to the post-thawing medium, whereas plasma and acrosomal membrane integrity ( > 0.05) and lipid peroxidation ( > 0.05) were unchanged. In conclusion, despite the centrifugation effects, the addition of SP arising from the whole sperm-rich fraction to post-thawed boar semen decreased sperm lipid disorder without an influence of the sperm membrane integrity and peroxidation.

Immunoexpression of tryptase-positive mast cells in periapical granulomas and radicular cysts.

AIM: To evaluate and compare the immunoexpression of tryptase in samples of periapical granulomas (PGs) and radicular cysts (RCs) correlating it with the type of lesion, localization, intensity of the inflammatory infiltrate and thickness of the cystic epithelial lining, in order to gain insight into the phlogistic role of these cells in the lesions studied. METHODOLOGY: Twenty-five PGs and twenty-five RCs obtained from human teeth without endodontic treatment were submitted to morphological and immunohistochemical analysis using anti-tryptase antibody. Mast cells were identified and counted in three regions: intra-epithelial, central/superficial and deep portions. The data were analysed using the Mann-Whitney U-test (P < 0.05). RESULTS: In comparison with RCs, PGs exhibited higher immunoexpression of tryptase-positive mast cells located in both central/superficial and deep regions (P < 0.001 and P < 0.001, respectively). When considering the total number of mast cells and disregarding the location, the number of tryptase-positive mast cells increased gradually from RCs to PGs (P < 0.001). Lesions with inflammatory infiltrate grade III had greater number of tryptase-positive mast cells located in both central/superficial and deep regions than lesions with inflammatory infiltrates grade II (P = 0.045 and P = 0.025). When the location was ignored, the lesions with inflammatory infiltrate grade III also exhibited higher immunostaining of tryptase-positive mast cells (P = 0.01). CONCLUSIONS: Tryptase-positive mast cells were present in chronic periapical lesions in a larger number in periapical granulomas than in radicular cysts, in both central/superficial and deep regions.

Organic selenium supplementation increases PHGPx but does not improve viability in chilled boar semen.

This study evaluated the effects of dietary organic selenium (Se) on viability of chilled boar semen. Twelve boars were divided into three groups: control (CON), 0.3 mg kg(-1) sodium selenite; inorganic (INO), 0.5 mg kg(-1) sodium selenite and organic (ORG), 0.5 mg kg(-1) Se yeast. The experiment was conducted within 10 weeks, and analysis was performed fortnightly, in storage semen by 72 h. No effect was observed on motility; however, straightness and linearity percentages were higher (P < 0.05) in the animals receiving CON diet compared with INO group. Percentages of cells with both plasma and acrosomal intact membranes, lipidic membrane peroxidation and mitochondrial membrane potential were similar on all treatments. Animals receiving CON diet presented higher (P < 0.05) values of ATP when compared with INO group. The PHGPx was higher (P < 0.05) in animals that received ORG in comparison with INO group. In conclusion, organic selenium supplementation increases PHGPx but does not improve chilled semen viability in 72 h.

Gonadotropin-induced puberty does not impair reproductive performance of gilts over three parities.

The aim of this study was to evaluate the reproductive performance of three parities of gilts treated or not treated with gonadotropin to induce puberty. Sixty gilts received 600 IU of equine chorionic gonadotropin (eCG) followed by 2.5 mg of porcine luteinizing hormone (LH) 72 h later. Fifty-nine other gilts were exposed only to a mature boar for 15 min twice daily. Artificial insemination (AI) was performed at 0, 12 and 24 h after the detection of oestrus, and gestation was confirmed by ultrasound after 35 days. Sows were inseminated at the first post-weaning oestrus. The total numbers of piglets born, piglets born alive, stillborn, mummified foetuses, as well as pregnancy and farrowing rates were evaluated for each of the three parities. Culling rates, farrowing intervals and weaning-to-oestrous intervals (WEI) were also analysed. Mean age at puberty and oestrous manifestation were not significantly different between treatments (p = 0.0639; 179.20 ± 17.52 compared with 173.96 ± 16.94, 91.66% compared with 94.92%) across the experimental period. However, females that underwent puberty induction showed modest increases both in the number of total pigs born and in the number of piglets born alive. In conclusion, puberty induction through exogenous gonadotropin administration in field conditions did not induce a more concentrated first oestrous manifestation, but trended to a modest increase in the number of pigs born alive in the first parity and a reduced culling rate during the first gestation.

Resin composite class I restorations: a 54-month randomized clinical trial.

The objective of this longitudinal clinical randomized trial was to evaluate the clinical performance of a nanofilled and a nanohybrid resin composite in Class I occlusal restorations of posterior teeth over the course of 54 months. Forty-one adolescents participated in the study. The teeth were restored with Adper Single Bond 2 (3M ESPE) and nanofilled (Filtek Z350, 3M ESPE), nanohybrid (Esthet-X, Dentsply) and microhybrid Filtek Z250 (3M ESPE) used as a control. After 54 months, the restorations were evaluated in accordance with the modified United States Public Health Service criteria. The McNemar and Friedman tests were used for statistical analysis, at a level of significance of 5%. Five failed restorations were observed during the follow-up. A change to unacceptable restoration occurred for one Esthet-X, two Filtek Z350, and two Filtek Z250 restorations, which received the clinically unacceptable score, Charlie, for both anatomic form and marginal adaptation. Secondary caries and postoperative sensitivity occurred in one Filtek Z250 and one Filtek Z350 restoration. When the five evaluation periods (baseline and six, 12, 30, and 54 months) were compared, significant differences were found in the marginal adaptation of Filtek Z250 and Filtek Z350. Significant differences in the roughness criteria (p=0.005) were also observed when the three composites were compared after 54 months (Filtek Z350 > Filtek Z250 > Esthet-X), always within clinically acceptable limits. The materials investigated showed acceptable clinical performance for Class I restoration after 54 months. Long-term reevaluations are necessary for a more detailed analysis of these composites.

Subcellular expression and neuroprotective effects of SK channels in human dopaminergic neurons.

Small-conductance Ca(2+)-activated K(+) channel activation is an emerging therapeutic approach for treatment of neurological diseases, including stroke, amyotrophic lateral sclerosis and schizophrenia. Our previous studies showed that activation of SK channels exerted neuroprotective effects through inhibition of NMDAR-mediated excitotoxicity. In this study, we tested the therapeutic potential of SK channel activation of NS309 (25 µM) in cultured human postmitotic dopaminergic neurons in vitro conditionally immortalized and differentiated from human fetal mesencephalic cells. Quantitative RT-PCR and western blotting analysis showed that differentiated dopaminergic neurons expressed low levels of SK2 channels and high levels of SK1 and SK3 channels. Further, protein analysis of subcellular fractions revealed expression of SK2 channel subtype in mitochondrial-enriched fraction. Mitochondrial complex I inhibitor rotenone (0.5 µM) disrupted the dendritic network of human dopaminergic neurons and induced neuronal death. SK channel activation reduced mitochondrial membrane potential, while it preserved the dendritic network, cell viability and ATP levels after rotenone challenge. Mitochondrial dysfunction and delayed dopaminergic cell death were prevented by increasing and/or stabilizing SK channel activity. Overall, our findings show that activation of SK channels provides protective effects in human dopaminergic neurons, likely via activation of both membrane and mitochondrial SK channels. Thus, SK channels are promising therapeutic targets for neurodegenerative disorders such as Parkinson's disease, where dopaminergic cell loss is associated with progression of the disease.

Effect of sequence of insemination after simultaneous thawing of multiple semen straws on conception rate to timed AI in suckled multiparous Nelore cows.

The objective was to determine the effect of sequence of insemination after simultaneous thawing of multiple 0.5 mL semen straws on conception rate in suckled multiparous Nelore cows. The effect of this thawing procedure on in vitro sperm characteristics was also evaluated. All cows (N = 944) received the same timed AI protocol. Ten straws (0.5 mL) of frozen semen from the same batch were simultaneously thawed at 36 °C, for a minimum of 30 sec. One straw per cow was used for timed AI. Frozen semen from three Angus bulls was used. Timed AI records included sequence of insemination (first to tenth) and time of semen removal from thawing bath. For laboratory analyses, the same semen batches used in the field experiment were evaluated. Ten frozen straws from the same batch were thawed simultaneously in a thawing unit identical to that used in the field experiment. The following sperm characteristics were analyzed: sperm motility parameters, sperm thermal resistance, plasma and acrosomal membrane integrity, lipid peroxidation, chromatin structure, and sperm morphometry. Based on logistic regression, there were no significant effects of breeding group, body condition score, AI technician, and sire on conception rate, but there was an interaction between sire and straw group (P = 0.002). Semen from only one bull had decreased (P < 0.05) field fertility for the group of straws associated with the longest interval from thawing to AI. However, the results of the laboratory experiment were unable to explain the findings of the field experiment. Sperm width:length ratio of morphometric analysis was the single sperm characteristic with a significant interaction between sire and straw group (P = 0.02). It was concluded that sequence of insemination after simultaneous thawing of 10 semen straws can differently affect conception rates at timed AI, depending on the sire used. Nevertheless, the effects of this thawing environment on in vitro sperm characteristics, remain to be further investigated.

Proteomic analysis of Porphyromonas gingivalis exposed to nicotine and cotinine.

BACKGROUND AND OBJECTIVE: Smokers are more predisposed than nonsmokers to infection with Porphyromonas gingivalis, one of the most important pathogens involved in the onset and development of periodontitis. It has also been observed that tobacco, and tobacco derivatives such as nicotine and cotinine, can induce modifications to P. gingivalis virulence. However, the effect of the major compounds derived from cigarettes on expression of protein by P. gingivalis is poorly understood. Therefore, this study aimed to evaluate and compare the effects of nicotine and cotinine on the P. gingivalis proteomic profile. MATERIAL AND METHODS: Total proteins of P. gingivalis exposed to nicotine and cotinine were extracted and separated by two-dimensional electrophoresis. Proteins differentially expressed were successfully identified through liquid chromatography-mass spectrometry and primary sequence databases using MASCOT search engine, and gene ontology was carried out using DAVID tools. RESULTS: Of the approximately 410 protein spots that were reproducibly detected on each gel, 23 were differentially expressed in at least one of the treatments. A particular increase was seen in proteins involved in metabolism, virulence and acquisition of peptides, protein synthesis and folding, transcription and oxidative stress. Few proteins showed significant decreases in expression; those that did are involved in cell envelope biosynthesis and proteolysis and also in metabolism. CONCLUSION: Our results characterized the changes in the proteome of P. gingivalis following exposure to nicotine and cotinine, suggesting that these substances may modulate, with minor changes, protein expression. The present study is, in part, a step toward understanding the potential smoke-pathogen interaction that may occur in smokers with periodontitis.

Development of ternary and quaternary catalysts for the electrooxidation of glycerol.

This work consisted in the preparation of platinum-based catalysts supported on carbon (Vulcan XC-72) and investigation of their physicochemical and electrochemical properties. Catalysts of the C/Pt-Ni-Sn-Me (Me = Ru or Ir) type were prepared by the Pechini method at temperature of 350°C. Four different compositions were homemade: C/Pt(60)Sn(10)Ni(30), C/Pt(60)Sn(10)Ni(20)Ru(10), C/Pt(60)Sn(10)Ni(10)Ru(20), and C/Pt(60)Sn(10)Ni(10)Ir(20). These catalysts were electrochemically and physically characterized by cyclic voltammetry (CV), chronoamperometry (CA) in the presence of glycerol 1.0 mol dm(-3), X-ray diffraction (XRD), and high-resolution transmission electron microscopy (HRTEM). XRD results showed the main peaks of face-centered cubic Pt. The particle sizes obtained from XRD and HRTEM experiments were close to values ranging from 3 to 8.5 nm. The CV results indicate behavior typical of Pt-based catalysts in acid medium. The CV and CA data reveal that quaternary catalysts present the highest current density for the electrooxidation of glycerol.

Diagnostic accuracy of exhaled nitric oxide in exercise-induced bronchospasm: Systematic review.

INTRODUCTION: The gold-standard method for the diagnosis of exercise-induced bronchospasm (EIB) is an exercise test combined with spirometry. However, this test is expensive, time consuming and requires specialized equipment and trained personnel. Exhaled nitric oxide (eNO) is a fast, easy, noninvasive method for the diagnosis of EIB. The aim of the present study was to assess the accuracy of the measurement of eNO for the diagnosis of EIB through a systematic review of the literature. METHODS: A search was carried out in the PubMed, Lilacs, SciELO and SCOPUS databases by two independent researchers. RESULTS: Fifty-six papers were found. Following the application of the eligibility criteria to the title, abstract and text, six papers remained for analysis. There was a significant heterogeneity in sex (X(2)=56.44, p=0.000) and clinical spectrum (X(2)=504.00, p=0.000) between studies. In children between 3.8 and 7.8 years old a cutoff point >28ppb EIB can be ruled in and in children between 5 and 16 years old at a cutoff point <20EIB can be ruled out. For adults a cutoff point <7EIB can be ruled out and it can be ruled in with a cutoff point >12. Four papers reported negative predictive values above 88%. CONCLUSION: The measurement of eNO seems to be effective for ruling in and ruling out EIB in some specific groups. Therefore, the measurement of eNO levels could be an important tool to safely avoid the need for an exercise test when the result is negative, reducing the individual and economic impact of this disease.

Effects of discontinuous Percoll gradient centrifugation on the quality of bovine spermatozoa evaluated with computer-assisted semen analysis and fluorescent probes association.

The objective of this study was to evaluate the quality of bovine frozen-thawed sperm cells after Percoll gradient centrifugation. Frozen semen doses were obtained from six bulls of different breeds, including three taurine and three Zebu animals. Four ejaculates per bull were evaluated before and after discontinuous Percoll gradient centrifugation. Sperm motility was assessed by computer-assisted semen analysis and the integrity of the plasma and acrosomal membranes, as well as mitochondrial function, were evaluated using a combination of fluorescent probes propidium iodide, fluorescein isothiocyanate-conjugated Pisum sativum agglutinin and 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazolcarbocyanine iodide. The procedure of Percoll gradient centrifugation increased the percentage of total and progressive sperm motility, beat frequency, rectilinear motility, linearity and rapidly moving cells. In addition, the percentage of cells with intact plasma membrane and mitochondrial membrane potential was increased in post-centrifugation samples. However, the percentage of sperm cells with intact acrosomal membrane was markedly reduced. The method used selected the motile cells with intact plasma membrane and higher mitochondrial functionality in frozen-thawed bull semen, but processing, centrifugation and/or the Percoll medium caused damage to the acrosomal membrane.