Repositório RCAAP

Diplodia ear rot caused by the fungus Stenocarpella maydis (Berkeley) and Stenocarpella macrospora (Earle) have become one of the most important limiting factors for the production of Corn (Zea mays L.) in Brazil. The fungus can attack the stalks, leaves and the grain causing significant reductions on yield and the overall quality of the grain, since it can produce micotoxinas that are dangerous to livestock. Resistance to ear rot by Stenocarpella sp in corn is quantitative and highly influenced by the environment and even that artificial inoculation techniques are available to screen for the disease the overall cost is very expensive. The objective of this study was the identification of quantitative trait loci (QTL s) associated with ear rot resistance by Stenocarpella sp in one breeding population composed of 141 doublehaploid progenies resulted from the cross among the resistant inbred MONDR1 and the susceptible inbred MONDS1 in testcrosses with the susceptible tester MONDS5. Testcrosses were evaluated at harvest time after artificial inoculation for ear rot at three different locations in the central region of Brazil during the 2005/06 summer season. Thru Composite interval mapping (CIM), a total of three QTL s (LOD>2.5) for ear rot resistance were identified at chromosomes 2, 3 and 5, all together accounting for up 26% of total phenotypic variation for this character. The identification of two QTL s for ear rot resistance coming from the susceptible parent MONDS1 appear to indicate the presence of the phenomena of transgressive segregation. Additionally we were able to identify six double-haploid progenies with high level of resistance to ear rot by Stenocarpella (MDH15, MDH443, MDH95, MDH2, MDH120 e MDH81), being those recommended for their incorporation into the breeding program as new breeding sources for the Central Brazil regions.

To the ageing process are associated the losses social, cognitive, neuromotors and metabolic, capable of compromising seriously the quality of aged life, leading to the loss of autonomy and physical, psychological and economic dependence, related to the family and society. It is established that the regular practice of physical exercise contributes to healthy ageing, thus showing an increase in expectation of life. Physical exercises regularly practiced inhibit organic changes that are associated to the degenerative process, contribute to the rehabilitation of certain diseases that may increase the rates of morbidity and mortality, acting also on mental and cognitive health. For this reason, has been established strategy with the aim of encouraging the aged to join the regular practice of physical exercise, because their effects are arising from the practice reasonably prolonged and reversible. Thus, in particular, the physical exercises are considered as a typical case of adjustment to stress the stimulus and not as adaptation. The exercise can induce changes in concentration, activity and composition of plasma and salivary several components, such as lactate, immunoglobulin, proteins, nitric oxide, amylase and electrolytes. Saliva is composed primarily of water, and also contain organic and inorganic constituents. The control of the salivary secretion is mediated by a combined share of parasympathetic and sympathetic stimuli, where the adrenergic system operates primarily in the secretion of proteins and cholinergic in regulating the secretion of electrolytes and water. This study examined the effects of acute exercise in the lactate plasmatic and salivary biomarkers (total protein, amylase, nitric oxide and immunoglobulin A) in the active aged and aged athletes.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Mestre em Genética e Bioquímica

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Food additives are used by the food industry in order to enhance the aroma, flavor and texture of foods. Of all the additives used colors are the most genotoxic. The azo dyes, derived from oil, used by industries, are the tartrazine and red #40. The SMART wing test was used to verify the possible genotoxic effects of colors in somatic cells of Drosophila melanogaster. For this evaluation were used larvae of 48 hours, descendants of the Standard Cross (ST) and High Bioactivation (HB) that who were treated with tartrazine in concentrations 1.5, 2.5 and 3.0 mg / mL and 5, 10 and 20 mg / mL for the red #40. The results showed significant increase of spots in the ST descendants for tartrazine and HB for the red #40. We concluded that the artificial colors tartrazine and red #40 are genotoxic in the doses used for the study.

Universidade Federal de Uberlândia

In this work a new metalloproteinase (BthMP) was purified from the snake venom of Bothrops moojeni. This enzyme was homogeneous by native and SDSPAGE it showed polypeptide chain of 23,5 kDa, pI = 7,1 and N-terminal blocked. BthMP is comprised of high proteolytic activity on casein, fibrin and bovine fibrinogen, but no coagulating, esterase, phospholipase A2 activities, and lightly hemorrhagic; it was inhibited by EDTA, EGTA and 1,10-phenanthroline and maintained its activity on pH of 7,0 at 9,0 and temperature of 5 to 40°C. Assays with metal ions showed that Ca++ is an activator, whereas Zn++ and Hg++ inhibited about 50 and 80%, respectively. The edema evidenced the important role of the toxin in the inflamatory activity of the venom. BthMP also caused uncloting, and provoked histological alterations in gastrocnemius muscle of mice inducing hemorrhage, necrosis and leucocytic infiltrate. The molecular mass and the inhibition assays suggest that the metalloproteinase BthMP belongs to class P-I SVMPs.

Centro Universitário de Patos de Minas

Fundação de Amparo a Pesquisa do Estado de São Paulo

Fundação de Amparo a Pesquisa do Estado de São Paulo

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Fundação de Amparo a Pesquisa do Estado de Minas Gerais

Universidade Federal de Uberlândia

CHAPTER II: The alpha-amylases (α-1,4-D-glucan-4-glucanohydrolases, EC 3.2.1.1) are enzymes responsible for the digestion of carbohydrates and are found in saliva and in the pancreatic juice. The primary sequences of the salivary (HSA) and pancreatic (HPA) alpha-amylases show structural similarity of 99%. This standart homology suggests that the HSA can be target of experimental studies of the digestion of carbohydrates inhibition, besides studies showed that potential inhibitors have similar behavior to HPA and HSA. Considering the benefits of noninvasive collection of saliva in relation of pancreatic juice, in this present study obtained a fraction called HSA-CTI. Preparations of the crude extract of the bark of Pouteria sp. was tested about the inhibitory effect of enzymatic activity of the HSA-CTI. Samples of saliva were frozen for 48h, centrifugation and the supernatant was subjected to chromatography in Q-Sepharose column (QS-column) equilibrated in 50mM Tris-HCl buffer at pH 8.0 containing 10mM EDTA and 10mM EGTA. The bound proteins were eluted from QS-column with a gradient concentration of NaCl (0-1M). SDS-PAGE, Western blotting assays and amylase activity measured were performed of the obtained fractions. The HSA-CTI fraction not interacted with the column, and thus prepared by lyophilization and stored in the frozen until realization of the inhibition assays. Aqueous preparations for infusion (EAP-C), deccotion (EAP-C), hydroalcoholic (EHP-C) and ethanolic (EEP-C) of the stem bark extract (10mg/mL in DMSO) have assays by pre-incubation at 10 and 30min at 37ºC with the HAS-CTI (1:10). Only the polypeptide of 56Kda, abundant in the fraction, exhibited cross-reaction with anti-HSA antibody. The assay inhibition showed that stem bark extract has effective in to inhibit the HSA-CTI activity. These results indicate that the HSA-CTI can be obtained by a rapid chromatography method can be used in tests of inhibition from plant extracts. The extract of Pouteria sp. presented as a potential candidate for studies of fractionation and discovery of new substances with activity on these enzymes. CHAPTER III: Preliminary studies about extracts from plants of the kind of Pouteria (Sapotaceae) deal their potential to inhibit human alpha-amylase. These studies may involve the discovery of new sources to reduce post-prandial hyperglycemia, important in the treatment of diabetes and obesity. The active components of Pouteria sp. are still mostly unknown, therefore, the present study fractionated and investigated the substances present in the extract of hydroalcoholic Pouteria sp. with the potential inhibitory on the salivary amylase in vitro. The extract has fractionated in Sephadex LH 20 column equilibrated in methanol and washed with water following by acetone. All the fractions (POUN) was assayed to inhibity the alpha-amylase in vitro. POUN 2 and 3 fractions have injected in semipreparative HPLC (Supecolsyl LC-18 column, mobile phase methanol: water) and analyzed in analytical HPLC (Supecolsyl LC-18 Sp column, mobile phase methanol: acetic acid 0.1%). Assay of inhibition showed that fraction POUN7 exhibited inhibition similar of the crude extract with 40.22% and fractions POUN 2 and 3 exibited inhibition with 15% of the amylase activity. The fraction POUN7 has 48.81% of the constitute it in tannin and represent 35% of the composition of extract. The stem bark crude extract Pouteria sp. have composition it rich in tannin, in addition this extract is potential to others studies, due to this substances have involvement in others therapeutic function.

Background: Adenoviruses (AdVs) are important cause of acute respiratory disease (ARD), gastroenteritis, conjunctivitis and urinary infections in humans. Objectives: Detection of AdVs by immunofluorescence assay (IFA) and by polymerase chain reaction (PCR) in nasopharyngeal aspirates of children less than 5 years old presenting ARD in Uberlândia, MG, as well as, comparison of two PCR assays and identification of serotypes that circulated in this region. Study Design: A total of 468 clinical specimens was collected from November 2000 to April 2007 and tested by IFA for adenovirus detection and other viruses. After that, the DNA of the 126 in natura negative/inconclusive samples by IFA which were also negative for rhinovirus by RT-PCR, were extracted by Trizol® and tested by PCRAraújo (Araújo et al, 2001) for adenovirus detection. The positive specimens for adenovirus were inoculated into HEp-2 and A-549 continuous cell lineages. In addition, the DNA of either, in natura samples and cell culture-scrapped samples, were extracted by using the QIAmp DNA Mini Kit (QIAGENTM Valencia, CA) and tested again by PCRAraujo and by PCRAllard (Allard et al., 2001) in order to compare the sensitivity/specificity of both tests. In addition, the serotypes were identified from the nucleotide sequencing of PCR products positive for adenovirus. Results: From the 468 samples, 33 (7.1%) were positive for AdVs, 14 by IFA and 19 by PCRAraujo. From the 32 specimens inoculated in cell culture, it was possible to isolate AdVs in 16. The comparison of the results obtained from the DNA of the 33 in natura samples extracted by the QIAmp DNA Mini Kit (QIAGENTM Valencia, CA) showed that the sensibility of PCRAraujo was a little higher than PCRAllard (92.9% and 90.0%, respectively). However, the first PCR presented a lower specificity than the second one (57.9% and 91.3%, respectively). The serotype AdV2 was detected in almost 60.0% (7/12) of those identified. Conclusions: AdVs were detected in 7.1% of the clinical samples in children with ARD throught the combination of two methods, IFA and PCR. The analysis of the sensibility and specificity of the two PCR assays, showed that PCRAllard presented a little lower sensibility than PCRAraujo and higher specificity. The serotype AdV2 was identified in 7 of the 12 AdVs sequenced samples.

Due to the set of changes and factors corn crop has been subjected in the last few decades, earliness became one of the major characters for addition of genetic value and adaptability to currently cultivated corn hybrids. Thus, selection of characters related to earliness has been of large interest to corn breeding programs. The aim of this work was to estimate genetic parameters related to earliness in a tropical corn population adapted to the central region of Brazil. In this study were evaluated 188 F4 testcrosses in an expanded statistical block design at six locations and plant density of 70,000pl ha-1. Significant differences were detected between the testcrosses (G), Location (L) and GxL interaction. The heritability coefficient for these testcrosses varied from 35.25% for stalk and root lodging (TQA) and 68.91% for pollen shed (FM). Genetic gain estimates showed that it is possible to improve each of these characters individually, via direct selection. However, estimates of indirect effect showed that correlated changes, in general, are unfavorable. The estimated genetic parameters suggest that utilization of selection indexes that, besides grain yield, include characters such as grain moisture, pollen shed, silk, stalk and root lodging to select the testcrosses, under normal development condition the crop, can lead to the development of hybrids with high grain yield and earliness, simultaneously.

Fundação de Amparo a Pesquisa do Estado de Minas Gerais

Conselho Nacional de Desenvolvimento Científico e Tecnológico

NaCl is a classic osmoregulatory agent that in isotonic conditions with the plasma is able to stabilize the red blood cells (RBC) in a relaxed (R) state, where these cells congregate a certain degree of stability with the capacity of exercise properly all its functions. The ethanol is a classic chaotropic agent, capable of promoting denaturation, but is also an osmolyte, able to promote stabilization of RBC. In 0.9% w/v NaCl and between 0 and 24% v/v ethanol, the RBC suffer lysis, but between 24 and 32%, the RBC are stabilized by the action of ethanol. This stabilization forms compacted or tight (T) RBC, which lost however many cell functions. In this work we studied the effect of concentrations of NaCl at 0.5, 0.9 and 1.1% w/v on the fixed time incubation (30 min) of human blood with concentrations of ethanol between 0 and 32%v/v. The RBC lysis and stabilization transitions by ethanol were described by sigmoids and characterized by their lysis half-point (D50) and stabilization (S50) transitions, respectively, and also by the amplitude (dX) and height (h) of those curves. The average value of D50 increased from 12.61 to 14.29%, but fell back again to 13.97% of ethanol/100 mL of 0.5, 0.9 and 1.1% w/v NaCl, respectively. The average value of S50 fell from 27.26 to 26.22 and 25.99% of ethanol/100 mL of solution with the increase in the concentration of NaCl solution of 0.5 to 0.9 and mL of 1.1% w/v saline, respectively. These results indicate that hypertonic saline solution potentiated the stabilizing effect of ethanol, certainly moving the RBC from of the state R to the state T.