Pyruvic acid as attenuator of water deficit in cotton plants varying the phenological stage

The lack of water during crop growth causes damage to any production system, especially when it occurs during the initial establishment or beginning of the reproductive stage. Although cotton can be properly managed in regions with water limitation, its yield is affected at different levels according to the genetics of the cultivar adopted. Exogenous application of some organic components has shown a stress-mitigating effect and can be a valuable procedure to enhance the yield of water stress-sensitive cultivars. The objective of this work was to evaluate the benefits of exogenous application of pyruvic acid (100 µM) in cotton plants under water deficit varying the phenological stage of the crop. The experiment was conducted in a greenhouse, where the plants were grown in pots and subjected to seven days of water suspension, initiated individually in stages V2 and B1. Each pot contained two plants. The treatments adopted were: T1 - control, T2 - water suppression; and T3 - water suppression + pyruvate application. The design was randomized blocks in a factorial scheme (3 × 3) with three replicates. The reductions in gas exchange and growth of the cultivars BRS Seridó, CNPA 7MH and FM 966 were more significant in the reproductive stage, especially for FM 966, which was more sensitive. Pyruvate application reduced the effects of water suppression on boll production by 31% in BRS Seridó and 34% in CNPA 7MH and FM 966.

Respiratory gases, air pollution and epilepsy

A growing number of studies have shown that exposure to air pollutants such as particulate matter and gases can cause cardiovascular, neurodegenerative and psychiatric diseases. The severity of the changes depends on several factors such as exposure time, age and gender. Inflammation has been considered as one of the main factors associated with the generation of these diseases. Here we present some cellular mechanisms activated by air pollution that may represent risk factors for epilepsy and drug resistance associated to epilepsy.

Ferrule Design Does Not Affect the Biomechanical Behavior of Anterior Teeth Under Mechanical Fatigue: An In Vitro Evaluation

Objectives:

To investigate the survival and failure mode of fiber-post resin restorations over preparations with different ferrule designs when submitted to a fatigue load test.

Methods and Materials:

Fifty bovine incisors were selected and divided into five groups (n=10) according to ferrule design: a no-ferrule group, a 2-mm circumferential ferrule group, a 2-mm buccal ferrule group, a 2-mm lingual ferrule group, and a 2-mm buccal and lingual ferrule group. The fiberglass post was cemented and the composite core was built up and prepared, followed by cementation of a full composite crown. The samples were subjected to a cyclic fatigue test with loading applicator at 135°; a staircase approach was used until fracture. Survival (cycles to fracture) and failure modes were recorded. Survival data were analyzed with the log-rank test, while Kruskal-Wallis and Fisher exact tests were used to analyze failure mode data (α=0.05).

Results:

The median number of cycles to fracture ranged from 215,000 to 236,153. The log-rank test showed no statistically significant difference in survival rates among the groups (p=0.82). Regarding failure mode, three types were observed: I, post and/or core fracture; II, root fracture in the cervical third; and III, root fracture in the middle third. No statistical difference was observed among the groups (Kruskal-Wallis test, p=0.147).

Conclusion:

The ferrule design had no effect on fatigue resistance or failure mode of endodontically treated incisor teeth restored with a fiber post, composite core buildup, and composite crown.

Temporal and tissue expression of genes involved in buds of earliness cotton cultivar

Gene sequences previously identified in Arabidopsis buds were used as references in order to estimate temporal and tissue expression in buds, leaves, stem, and root tissues in cotton plants. Buds were evaluated during 3 phases: 2-8, 10-12, and 14-20 mm. Primers were designed for the ARF6, ATFY, and SEUSS genes for use in semi-quantitative reverse transcription-polymerase chain reaction and quantitative reverse transcription-polymerase chain reaction. Different levels of expression of the 3 genes were confirmed in cotton buds as well as in other tissues. The peak of gene expression was observed in buds sized 10-12 mm, after which expression decreased in larger buds. The gene GhFYPP3 was the most promising for further prospection of promoter regions, with regular expression patterns observed in bud sizes 10-12 and 14-20 mm. This trait was not observed in others genes.

Insecticidal and repellent effects of tea tree and andiroba oils on flies associated with livestock

This study aimed to evaluate the insecticidal and repellent effects of tea tree, Melaleuca alternifolia (Myrtales: Myrtaceae), and andiroba, Carapa guianensis (Sapindales: Meliaceae), essential oils on two species of fly. For in vitro studies, free-living adult flies were captured and reared in the laboratory. To evaluate the insecticidal effects of the oils, adult flies of Haematobia irritans (L.) and Musca domestica L. (both: Diptera: Muscidae) were separated by species in test cages (n = 10 per group), and subsequently tested with oils at concentrations of 1.0% and 5.0% using a negative control to validate the test. Both oils showed insecticidal activity. Tea tree oil at a concentration of 5.0% was able to kill M. domestica with 100.0% efficacy after 12 h of exposure. However, the effectiveness of andiroba oil at a concentration of 5.0% was only 67.0%. The insecticidal efficacy (100.0%) of both oils against H. irritans was observed at both concentrations for up to 4 h. The repellency effects of the oils at concentrations of 5.0% were tested in vivo on Holstein cows naturally infested by H. irritans. Both oils demonstrated repellency at 24 h, when the numbers of flies on cows treated with tea tree and andiroba oil were 61.6% and 57.7%, respectively, lower than the number of flies on control animals. It is possible to conclude that these essential oils have insecticidal and repellent effects against the species of fly used in this study.

Influence of tea tree oil (Melaleuca alternifolia) on the cattle tick Rhipicephalus microplus

The aim of this study was to verify the influence of tea tree oil (TTO) (Melaleuca alternifolia) tested in its pure and nanostructured (TTO nanoparticles) forms on the reproduction of female Rhipicephalus microplus. For our purpose, female ticks were collected from naturally infected animals and treated in vitro with TTO (1, 5, and 10 %) and TTO nanoparticles (0.075, 0.375, and 0.75 %). In order to validate the tests, they were performed in triplicate using positive (amitraz) and negative (untreated) controls. It was possible to observe that pure TTO (5 and 10 %) and TTO nanoparticles (0.375 and 0.75 %) showed 100 % reproductive inhibition on female ticks. Additionally, pure TTO (1 %) also showed an acaricide effect (70 %), similarly to the positive control (78.3 %). This is the first study demonstrating the activity of pure TTO and TTO nanoparticles on female ticks. Therefore, based on these results, we were able to show that both forms and all concentrations of M. alternifolia affected tick reproduction by inhibiting egg laying and hatching. We were also able to show that TTO nanoparticles potentiated the inhibitor effect of pure TTO on the reproduction of R. microplus.

Association between the presence of a partially erupted mandibular third molar and the existence of caries in the distal of the second molars

The objective of this study was to verify, using periapical radiographs, whether a partially erupted mandibular third molar is a factor in the presence of dental caries on the distal surface of the adjacent second molar. Two-forty six high quality periapical radiographs were selected, each showing a partially erupted mandibular third molar. The variables analyzed were: tooth number; gender; age; radiographic presence of caries on the distal surface of the adjacent molar; Pell and Gregory classification; Winter classification; angulation and distance between the second and mandibular third molar. The examiners were previously calibrated to collect data (kappa statistics from 0.87 to 1.0). The prevalence rate of caries on the distal surface of the second molar was 13.4%. In the logistical multivariate regression analysis, the angulation (OR=8.5; IC95%: 1.7-43.8; p=0.011) and the gender (OR=3.3; IC95%: 1.4-7.7; p=0.005) remained statistically significant after an age adjustment was made. The results indicate that the presence of a partially erupted mandibular third molar with an angulation of 31 degrees or more, is a risk factor for caries on the distal surface of the mandibular second molars.

New applications for bismuth(III) salts in organic synthesis: from bulk chemicals to steroid and terpene chemistry

Bismuth(III) salts are currently considered efficient and "ecofriendly" reagents and catalysts for the development of new applications in organic synthesis. The preparation of bismuth(III) triflate and its analogues is reviewed as well as some of their applications to the synthesis of bulk chemicals via electrophilic addition and cyclization reactions. The use of bismuth(III) salts in the development of new chemical processes involving steroids and terpenes as substrates is also discussed.

3-Oxo-18α-olean-28,13β-olide

The title terpene, C₃₀H₄₆O₃, is a 28,13β-lactone of oleanolic acid prepared with bis­muth trifluoro­methane­sulfonate (OTf), Bi(OTf)₃·xH₂O. All rings are trans-fused. The X-ray study shows the inversion of the orientation of 18-H in the lactonization reaction. A quantum chemical ab-initio Roothaan Hartree–Fock calculation of the equilibrium geometry of the isolated mol­ecule gives values for bond lengths and valency angles in close agreement with experimental values. The calculation also reproduces the observed mol­ecular conformation, with puckering parameters that agree well with those determined from the crystallographic study.

3β-Hy-droxy-lup-20(29)-en-28-yl 1H-imidazole-1-carboxyl-ate

The title triterpene, C(34)H(52)N(2)O(3), is a C-28 carbamate derivative of betulin prepared in a one-step reaction from the commercially available 1,1'-carbonyl-diimidazole (CDI). All rings are fused trans. The X-ray study shows the retention of the configuration of C-28 with respect to the known chiral centres of the molecule. In the crystal, the mol-ecules are O-H⋯O hydrogen bonded via the hy-droxy group and the carbonyl group of the carbamate function into chains running along the c axis. A quantum-mechanical ab initio Roothaan Hartree-Fock calculation of the equilibrium geometry of the isolated mol-ecule gives values for bond-lengths and valency angles close to the experimental values. The calculations also reproduce the mol-ecular conformation well, with calculated puckering parameters that agree well with the observed values.

19β,28-Ep-oxy-18α-olean-3β-ol

The title triterpene, C₃₀H₅₀O₂, is an 18α-oleanane derivative prepared by the Wagner–Meerwein rearrangement of betulin with Bi(OTf)₃.xH₂O (OTF is trifluoromethanesulfonate). There are two symmetry-independent mol­ecules in the asymmetric unit that show no significant differences concerning bond lengths and angles. The conformation of the six-membered rings is close to a chair form, while the five-membered epoxide rings adopt envelope conformations. All rings are trans-fused. In the crystal, mol­ecules are held together by O—H⋯O hydrogen bonds. A quantum-mechanical ab initio Roothan Hartree–Fock calculation on the isolated mol­ecule gives values for bond lengths and valency angles close to the experimental values. The calculations also reproduce well the mol­ecular conformation with calculated puckering parameters that match well the observed values.

Air quality improvements using European environment policies: a case study of SO2 in a coastal region in Portugal

The European Union (EU) has defined several efforts for preventing and controlling air pollution that have led to a generalized reduction of health risks and environmental effects. One example of these efforts was the establishment of legislation that imposed a reduction of sulfur content in fuels, switching to cleaner fuels for industry and motor vehicles (Auto-Oil Directives). The goal of this study was to evaluate the first trends in the air quality of Oporto Metropolitan Area (Oporto-MA) related to implementation of these directives in Portugal since 2000. Therefore, sulfur dioxide (SO2) concentration data from air quality monitoring sites were analyzed for the period 1999 through 2003. It was observed that daily SO2 concentrations in the industrial area are much higher than those of the urban and rural areas, reflecting the influence of the industrial sector. The annual SO2 concentrations for the consecutive years of analysis decreased considerably for all the monitoring sites. A considerable decrease in SO2 emissions was also observed for the same period. According to EU legislation, the exceedances of the SO2 recommended limit values decreased significantly. In conclusion, this analysis shows evidence that SO2 concentrations are decreasing, and that this is consistent with the implementation of the legislation and control of the sources of pollution. Nevertheless, the potential for human health risks still persists, particularly in industrialized areas. It is expected that SO2 concentration levels in ambient air of Oporto-MA will continue to decrease in the coming years, following the present European trends.

Relevant aspects of air quality in Oporto (Portugal): PM10 and O3

The air quality Framework Directive (FWD) and the correspondent Daughter Directives defined the new strategy for air quality management in Europe. In general, the new standards are more restrictive than those established by the previous legislation. In Portugal, some difficulties can be previewed to achieve those new standards. Thus, this paper aims at evaluating the impact of application of the FWD to Oporto Metropolitan Area in what concerns to the most critical air pollutants in the area (PM10 and O3). The specific objectives were: (i) to analyse the concentration exceedances between 1999 and 2001; (ii) to identify the main emission sources; (iii) to evaluate the possibility of a new redistribution of the existing monitoring sites; (iv) to contribute to the definition of a new strategy for air quality management. The results showed that; (i) the standard values for PM10 and O3 were largely surpassed, possibly concluding that the FWD application implies a strong impact on the air quality management strategies; (ii) the main emission sources (road traffic and the neighbour stationary sources localised upwind) affect all the Metropolitan area through intra-region pollutant transport; (iii) it is safer maintaining the site localisation to avoid previewing exceedances through mathematical correlations; (iv) the reduction of PM10 and of ozone precursors must be performed considering new technologies for 'cleaner production' and gaseous depuration, a rigorous urban and territory planning, the creation of an efficient public transport network and the definition of strict measures for car maintenance.

In vitro antimicrobial activity of a new series of 1,4-naphthoquinones

The antibacterial activity of a series of 1,4-naphthoquinones was demonstrated. Disk diffusion tests were carried out against several Gram-positive and Gram-negative bacteria. The compound 5-amino-8-hydroxy-1,4-naphthoquinone was the most effective, presenting inhibition zones measuring 20 mm against staphylococci, streptococci and bacilli at 50 microg/ml. Methicillin-resistant Staphylococcus aureus and several clinical isolates of this bacterium were also inhibited. Naphthazarin, 5-acetamido-8-hydroxy-1,4-naphthoquinone, and 2,3-diamino-1,4-naphthoquinone were the next most active compounds. The minimal inhibitory concentration of the active compounds was determined against S. aureus, ranging from 30 to 125 microg/ml. All compounds presented a minimal bactericidal concentration higher than 500 microg/ml, indicating that their effect was bacteriostatic. The EC50, defined as the drug concentration that produces 50% of maximal effect, was 8 microg/ml for 5-amino-8-hydroxy-1,4-naphthoquinone against S. aureus, S. intermedius, and S. epidermidis. These results indicate an effective in vitro activity of 5-amino-8-hydroxy-1,4-naphthoquinone and encourage further studies for its application in antibiotic therapy.

Cyclic AMP increases the survival of ganglion cells in mixed retinal cell cultures in the absence of exogenous neurotrophic molecules, an effect that involves cholinergic activity

Natural cell death is a well-known degenerative phenomenon occurring during development of the nervous system. The role of trophic molecules produced by target and afferent cells as well as by glial cells has been extensively demonstrated. Literature data demonstrate that cAMP can modulate the survival of neuronal cells. Cultures of mixed retinal cells were treated with forskolin (an activator of the enzyme adenylyl cyclase) for 48 h. The results show that 50 microM forskolin induced a two-fold increase in the survival of retinal ganglion cells (RGCs) in the absence of exogenous trophic factors. This effect was dose dependent and abolished by 1 microM H89 (an inhibitor of protein kinase A), 1.25 microM chelerythrine chloride (an inhibitor of protein kinase C), 50 microM PD 98059 (an inhibitor of MEK), 25 microM Ly 294002 (an inhibitor of phosphatidylinositol-3 kinase), 30 nM brefeldin A (an inhibitor of polypeptide release), and 10 microM genistein or 1 ng/ml herbimycin (inhibitors of tyrosine kinase enzymes). The inhibition of muscarinic receptors by 10 microM atropine or 1 microM telenzepine also blocked the effect of forskolin. When we used 25 microM BAPTA, an intracellular calcium chelator, as well as 20 microM 5-fluoro-2'-deoxyuridine, an inhibitor of cell proliferation, we also abolished the effect. Our results indicate that cAMP plays an important role controlling the survival of RGCs. This effect is directly dependent on M1 receptor activation indicating that cholinergic activity mediates the increase in RGC survival. We propose a model which involves cholinergic amacrine cells and glial cells in the increase of RGC survival elicited by forskolin treatment.

Structure-function relationships of the yeast cyclin-dependent kinase Pho85

The PHO85 gene of Saccharomyces cerevisiae encodes a cyclin-dependent kinase involved in both transcriptional regulation and cell cycle progression. Although a great deal is known concerning the structure, function, and regulation of the highly homologous Cdc28 protein kinase, little is known concerning these relationships in regard to Pho85. In this study, we constructed a series of Pho85-Cdc28 chimeras to map the region(s) of the Pho85 molecule that is critical for function of Pho85 in repression of acid phosphatase (PHO5) expression. Using a combination of site-directed and ethyl methanesulfonate-induced mutagenesis, we have identified numerous residues critical for either activation of the Pho85 kinase, interaction of Pho85 with the cyclin-like molecule Pho80, or substrate recognition. Finally, analysis of mutations analogous to those previously identified in either Cdc28 or cdc2 of Schizosaccharomyces pombe suggested that the inhibition of Pho85-Pho80 activity in mechanistically different from that seen in the other cyclin-dependent kinases.

Surface area of glaucoma implants and perfusion flow rates in rabbit eyes

PURPOSE

These experiments were designed to analyze the relationship between glaucoma drainage implant surface area and the physiological function of the surrounding encapsulation.

METHODS

Three sizes of Baerveldt implants were studied. Commercially available 200 mm devices were trimmed to reduce surface area to 100 and 50 mm (one side), respectively. Five samples of each size of device were studied 3 weeks after implantation in normal rabbit eyes by perfusing the drain tubes in vivo using a micromanometric system allowing precise control of flow rates. Additional eyes were analyzed at 12 weeks. Resistance to flow was calculated using Poiseuille's equation after at least three different flow rate readings for each implant, and a linear regression line was plotted for each eye. Flow rates at the pressures of 10, 15, 20, and 25 mm Hg were standardized by slope calculation and mean flow rate values for each size of implant compared statistically. Calculated flow per unit area (hydraulic conductivity) was calculated for each sized implant.

RESULTS

The perfusion flow tests demonstrated statistically significant differences for the values of resistance to flow and flow through the implants for the three surface areas tested. The 200 mm implants had higher flow rates and lower resistance values. A statistically significant inverse correlation was found between the surface area of the implant and the resistance to flow (p = 0.0002). A statistically significant direct correlation was also found between the surface area of the implant and the values of flow rates (p = 0.0002) through the capsules. Hydraulic conductivity of the capsules was virtually identical for all three sizes of implants tested.

CONCLUSION

The results demonstrate a direct relationship between the surface area of glaucoma implants and the filtering capacity of their surrounding capsules.

Effect of neonatal malnutrition on leucine renewal and protein biosynthesis in neurons of rats

Starting 1--3 days before delivery, pregnant rats were fed isocaloric diets containing either a low (5% casein) or a normal (20% casein) level of protein. At 14 days of age, the malnourished pups showed lower body, brain, and forebrain weights. The number of cells in the forebrain was lower and their size was smaller in the malnourished group. In order to study the turnover rate of 14C-leucine in the free amino acid pool and the rate of 14C-leucine incorporation into TCA-precipitable protein in neuronal cell bodies, a neuronal enriched fraction (NEF) was prepared. Malnutrition altered the free amino acid pool of the NEF by increasing the content of lysine+ornithine, glycine, and aspartic and glutamic acids and lowering that of histidine and threonine. The pools of the remaining amino acids were not altered. The turnover rate of free 14C-luecine was reduced to 60% of that of the controls. The rate of 14C-leucine incorporation into TCA-precipitable protein, corrected for its turnover rate in the free pool, was reduced to 64% of that of the controls.