225 resultados para TRYPSIN INHIBITORY-ACTIVITY


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Background: Preconception allergen immunization prevents neonatal allergen sensitization in mice by a complex interaction between regulatory cells/factors and antibodies. The present study assessed the influence of maternal immunization with ovalbumin (OVA) on the immune response of 3 day-old and 3 week-old offspring immunized or non-immunized with OVA and evaluated the effect of IgG treatment during fetal development or neonatal period. Results: Maternal immunization with OVA showed increased levels of Fc gamma RIIb expression in splenic B cells of neonates, which were maintained for up to 3 weeks and not affected by additional postnatal OVA immunization. Maternal immunization also exerted a down-modulatory effect on both IL-4 and IFN-gamma-secreting T cells and IL-4 and IL-12-secreting B cells. Furthermore, immunized neonates from immunized mothers showed a marked inhibition of antigen-specifc IgE Ab production and lowered Th2/Th1 cytokine levels, whereas displaying enhanced Fc gamma RIIb expression on B cells. These offspring also showed reduced antigen-specific proliferative response and lowered B cell responsiveness. Moreover, in vitro evaluation revealed an impairment of B cell activation upon engagement of B cell antigen receptor by IgG from OVA-immunized mice. Finally, in vivo IgG transference during pregnancy or breastfeeding revealed that maternal Ab transference was able to increase regulatory cytokines, such as IL-10, in the prenatal stage; yet only the postnatal treatment prevented neonatal sensitization. None of the IgG treatments induced immunological changes in the offspring, as it was observed for those from OVA-immunized mothers. Conclusion: Maternal immunization upregulates the inhibitory Fc gamma RIIb expression on offspring B cells, avoiding skewed Th2 response and development of allergy. These findings contribute to the advancement of prophylactic strategies to prevent allergic diseases in early life.

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The purpose of this study was to determine if performing isometric 3-point kneeling exercises on a Swiss ball influenced the isometric force output and EMG activities of the shoulder muscles when compared with performing the same exercises on a stable base of support. Twenty healthy adults performed the isometric 3-point kneeling exercises with the hand placed either on a stable surface or on a Swiss ball. Surface EMG was recorded from the posterior deltoid, pectoralis major, biceps brachii, triceps brachii, upper trapezius, and serratus anterior muscles using surface differential electrodes. All EMG data were reported as percentages of the average root mean square (RMS) values obtained in maximum voluntary contractions for each muscle studied. The highest load value was obtained during exercise on a stable surface. A significant increase was observed in the activation of glenohumeral muscles during exercises on a Swiss ball. However, there were no differences in EMG activities of the scapulothoracic muscles. These results suggest that exercises performed on unstable surfaces may provide muscular activity levels similar to those performed on stable surfaces, without the need to apply greater external loads to the musculoskeletal system. Therefore, exercises on unstable surfaces may be useful during the process of tissue regeneration.

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The in vitro schistosomicidal effects of the essential oil of Ageratum conyzoides L. (Ac-EO) against adult worms of Schistosoma mansoni is reported in this paper. Concerning this activity, Ac-EO was considered to be active, but less effective than the positive control (praziquantel, PZQ) in terms of separation of coupled pairs, mortality, decrease in motor activity, and tegumental alterations. However, Ac-EO caused an interesting dose-dependent reduction in the number of eggs of S. mansoni. Precocene I (74.30%) and (E)-caryophyllene (14.23%) were identified as the two major constituents of Ac-EO. These compounds were tested individually and were found to be much less effective than Ac-EO and PZQ. A mixture of the two major compounds in a ratio similar to that found in the Ac-EO was also less effective than Ac-EO, thus revealing that there are no synergistic effects between these components. These results suggest that the essential oil of A. conyzoides is very promising for the development of new schistosomicidal agents.

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Background: Drosophila retinal architecture is laid down between 24-48 hours after puparium formation, when some of the still uncommitted interommatidial cells (IOCs) are recruited to become secondary and tertiary pigment cells while the remaining ones undergo apoptosis. This choice between survival and death requires the product of the roughest (rst) gene, an immunoglobulin superfamily transmembrane glycoprotein involved in a wide range of developmental processes. Both temporal misexpression of Rst and truncation of the protein intracytoplasmic domain, lead to severe defects in which IOCs either remain mostly undifferentiated and die late and erratically or, instead, differentiate into extra pigment cells. Intriguingly, mutants not expressing wild type protein often have normal or very mild rough eyes. Methodology/Principal Findings: By using quantitative real time PCR to examine rst transcriptional dynamics in the pupal retina, both in wild type and mutant alleles we showed that tightly regulated temporal changes in rst transcriptional rate underlie its proper function during the final steps of eye patterning. Furthermore we demonstrated that the unexpected wild type eye phenotype of mutants with low or no rst expression correlates with an upregulation in the mRNA levels of the rst paralogue kin-of-irre (kirre), which seems able to substitute for rst function in this process, similarly to their role in myoblast fusion. This compensatory upregulation of kirre mRNA levels could be directly induced in wild type pupa upon RNAi-mediated silencing of rst, indicating that expression of both genes is also coordinately regulated in physiological conditions. Conclusions/Significance: These findings suggest a general mechanism by which rst and kirre expression could be fine tuned to optimize their redundant roles during development and provide a clearer picture of how the specification of survival and apoptotic fates by differential cell adhesion during the final steps of retinal morphogenesis in insects are controlled at the transcriptional level.

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AIM: To evaluate the effects of meal size and three segmentations on intragastric distribution of the meal and gastric motility, by scintigraphy. METHODS: Twelve healthy volunteers were randomly assessed, twice, by scintigraphy. The test meal consisted of 60 or 180 mL of yogurt labeled with 64 MBq (99m)Tc-tin colloid. Anterior and posterior dynamic frames were simultaneously acquired for 18 min and all data were analyzed in MatLab. Three proximal-distal segmentations using regions of interest were adopted for both meals. RESULTS: Intragastric distribution of the meal between the proximal and distal compartments was strongly influenced by the way in which the stomach was divided, showing greater proximal retention after the 180 mL. An important finding was that both dominant frequencies (1 and 3 cpm) were simultaneously recorded in the proximal and distal stomach; however, the power ratio of those dominant frequencies varied in agreement with the segmentation adopted and was independent of the meal size. CONCLUSION: It was possible to simultaneously evaluate the static intragastric distribution and phasic contractility from the same recording using our scintigraphic approach. (C) 2010 Baishideng. All rights reserved.

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Traumatic brain injury (TBI) produces several cellular changes, such as gliosis, axonal and dendritic plasticity, and inhibition-excitation imbalance, as well as cell death, which can initiate epileptogenesis. It has been demonstrated that dysfunction of the inhibitory components of the cerebral cortex after injury may cause status epilepticus in experimental models; we proposed to analyze the response of cortical interneurons and astrocytes after TBI in humans. Twelve contusion samples were evaluated, identifying the expression of glial fibrillary acidic protein (GFAP) and calcium-binding proteins (CaBPs). The study was made in sectors with and without preserved cytoarchitecture evaluated with NeuN immunoreactivity (IR). In sectors with total loss of NeuN-IR the results showed a remarkable loss of CaBP-IR both in neuropil and somata. In sectors with conserved cytoarchitecture less drastic changes in CaBP-IR were detected. These changes include a decrease in the amount of parvalbumin (PV-IR) neurons in layer II, an increase of calbindin (CB-IR) neurons in layers III and V, and an increase in calretinin (CR-IR) neurons in layer II. We also observed glial fibrillary acidic protein immunoreactivity (GFAP-IR) in the white matter, in the gray-white matter transition, and around the sectors with NeuN-IR total loss. These findings may reflect dynamic activity as a consequence of the lesion that is associated with changes in the excitatory circuits of neighboring hyperactivated glutamatergic neurons, possibly due to the primary impact, or secondary events such as hypoxia-ischemia. Temporal evolution of these changes may be the substrate linking severe cortical contusion and the resulting epileptogenic activity observed in some patients.

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Objective: The aim of this study was to evaluate the effect of laser irradiation on the amylase and the antioxidant enzyme activities, as well as on the total protein concentration of submandibular glands (SMG) of diabetic and non-diabetic rats. Background: Laser has been used aiming to improve some biochemical alterations observed in salivary glands of streptozotocin-induced diabetic rats. Materials and Methods: Ninety-six female rats were divided into eight groups: D0, D5, D10, and D20 (diabetic animals), and C0, C5, C10, and C20 (non-diabetic animals), respectively. Diabetes was induced by administering streptozotocin and confirmed later by the glycemia results. Twenty-nine days after diabetes induction, the SMG of groups D5 and C5, D10 and C10, and D20 and C20 were irradiated with 5, 10, and 20 J/cm(2), respectively. A diode laser (660nm/100mW) was used. On the day after irradiation, the rats were euthanized and the SMG were removed. Catalase, peroxidase, and amylase activities, as well as protein concentration, were assayed. Results: Diabetic rats without irradiation (D0) showed higher catalase activity (p<0.05) when compared to C0 (0.16 +/- 0.05 and 0.07 +/- 0.01 U/mg protein, respectively). However, laser irradiation of 5, 10, and 20 J/cm(2) reduced the catalase activity of diabetic groups (D5 and D20) to non-diabetic values (p>0.05). Conclusion: Based on the results of this study, laser irradiation decreased catalase activity in diabetic rats' SMG.

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An in vivo study was conducted to verify the ability of laser fluorescence (LF) to assess the activity status of occlusal caries in primary teeth, using different air-drying times. Occlusal sites (707) were examined using LF (DIAGNOdent) after air-drying for 3 s and 15 s, and the difference between readings (DIF15 s-3 s) was calculated. For concurrent validation of LF, visual criteria-Nyvad (NY) and Lesion Activity Assessment associated with the International Caries Detection and Assessment System (LAA-ICDAS)-were the reference standards for lesion activity. Histological exam using a pH-indicator dye (0.1% methyl red) was performed in 46 exfoliated/extracted teeth for criterion validation. LF readings and DIF15 s-3 s were compared using Kruskall-Wallis and Mann-Whitney tests. Receiver operating characteristic analyses were performed and validity parameters calculated, considering the caries activity assessment. Using NY, active lesions (3 s: 30.0 +/- 29.3; 15 s: 34.2 +/- 30.6) presented higher LF readings than inactive lesions (3 s: 17.0 +/- 16.3; 15 s: 19.2 +/- 17.3; p <0.05), different from LAA-ICDAS. Active cavitated caries resulted in higher LF readings (3 s: 50.3 +/- 3.5; 15 s: 54.7 +/- 30.2) than inactive cavitated caries (3 s: 19.9 +/- 16.3; 15 s: 22.8 +/- 16.8). Therefore, LF can distinguish cavitated active and inactive lesions classified by NY, but not by LAA-ICDAS; however, this difference might be related to the visual system rather than to LF. The air-drying time could be an alternative to improve the caries activity assessment; however, longer air-drying time is suggested to be tested subsequently. (C) 2010 Society of Photo-Optical Instrumentation Engineers. [DOI: 10.1117/1.3463007]

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The A1763 superstructure at z = 0.23 contains the first galaxy filament to be directly detected using mid-infrared observations. Our previous work has shown that the frequency of starbursting galaxies, as characterized by 24 mu m emission is much higher within the filament than at either the center of the rich galaxy cluster, or the field surrounding the system. New Very Large Array and XMM-Newton data are presented here. We use the radio and X-ray data to examine the fraction and location of active galaxies, both active galactic nuclei (AGNs) and starbursts (SBs). The radio far-infrared correlation, X-ray point source location, IRAC colors, and quasar positions are all used to gain an understanding of the presence of dominant AGNs. We find very few MIPS-selected galaxies that are clearly dominated by AGN activity. Most radio-selected members within the filament are SBs. Within the supercluster, three of eight spectroscopic members detected both in the radio and in the mid-infrared are radio-bright AGNs. They are found at or near the core of A1763. The five SBs are located further along the filament. We calculate the physical properties of the known wide angle tail (WAT) source which is the brightest cluster galaxy of A1763. A second double lobe source is found along the filament well outside of the virial radius of either cluster. The velocity offset of the WAT from the X-ray centroid and the bend of the WAT in the intracluster medium are both consistent with ram pressure stripping, indicative of streaming motions along the direction of the filament. We consider this as further evidence of the cluster-feeding nature of the galaxy filament.

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Total phenolic contents, antioxidant activity and chemical composition of propolis samples from three localities of Minas Gerais state (southeast Brazil) were determined. Total phenolic contents were determined by the Folin-Ciocalteau method, antioxidant activity was evaluated by DPPH, using BHT as reference, and chemical composition was analyzed by GC/MS. Propolis from Itapecerica and Paula Candido municipalities were found to have high phenolic contents and pronounced antioxidant activity. From these extracts, 40 substances were identified, among them were simple phenylpropanoids, prenylated phenylpropanoids, sesqui- and diterpenoids. Quantitatively, the main constituent of both samples was allyl-3-prenylcinnamic acid. A sample from Virginopolis municipality had no detectable phenolic substances and contained mainly triterpenoids, the main constituents being alpha-and beta-amyrins. Methanolic extracts from Itapecerica and Paula Candido exhibited pronounced scavenging activity towards DPPH, indistinguishable from BHT activity. However, extracts from Virginopolis sample exhibited no antioxidant activity. Total phenolic substances, GC/MS analyses and antioxidant activity of samples from Itapecerica collected monthly over a period of 1 year revealed considerable variation. No correlation was observed between antioxidant activity and either total phenolic contents or contents of artepillin C and other phenolic substances, as assayed by CG/MS analysis.

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The effect of daily ingestion of collagen hydrolysate (CH) on skin extracellular matrix proteins was investigated. Four-week-old male Wistar rats were fed a modified AIN-93 diet containing 12% casein as the reference group or CH as the treatment group. A control group was established in which animals were fed a non-protein-modified AIN-93 diet. The diets were administered continuously for 4 weeks when six fresh skin samples from each group were assembled and subjected to extraction of protein. Type I and IV collagens were studied by immunoblot, and activities of matrix metalloproteinase (MMP) 2 and 9 were assessed by zymography. The relative amount of type I and IV collagens was significantly (P<.05) increased after CH intake compared with the reference diet group (casein). Moreover, CH uptake significantly decreased both proenzyme and active forms of MMP2 compared with casein and control groups (P<.05). In contrast, CH ingestion did not influence on MMP9 activity. These results suggest that CH may reduce aging-related changes of the extracellular matrix by stimulating anabolic processes in skin tissue.

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Background: Macrophage migration inhibitory factor (MIF) has special pro-inflammatory roles, affecting the functions of macrophages and lymphocytes and counter-regulating the effects of glucocorticoids on the immune response. The conspicuous expression of MIF during human implantation and early embryonic development also suggests this factor acts in reproductive functions. The overall goal of this study was to evaluate Mif expression by trophoblast and embryo placental cells during mouse pregnancy. Methods: Mif was immunolocalized at implantation sites on gestation days (gd) 7.5, 10.5, 13.5 and 17.5. Ectoplacental cones and fetal placentas dissected from the maternal tissues were used for Western blotting and qRT-PCR assays on the same gestation days. Results: During the post-implantation period (gd7.5), trophoblast giant cells showed strong Mif reactivity. In later placentation phases (gds 10.5-17.5), Mif appeared to be concentrated in the junctional zone and trophoblast giant cells. Mif protein expression increased significantly from gd7.5 to 10.5 (p = 0.005) and from gd7.5 to 13.5 (p = 0.03), remaining at high concentration as gestation proceeded. Higher mRNA expression was found on gd10.5 and was significantly different from gd13.5 (p = 0.048) and 17.5 (p = 0.009). Conclusions: The up-regulation of Mif on gd10.5 coincides with the stage in which the placenta assumes its three-layered organization (giant cells, spongiotrophoblast and labyrinth zones), fetal blood circulation begins and population of uNK cells reaches high proportions at the maternal counter part of the placenta, suggesting that Mif may play a role in either the placentation or in the adaptation of the differentiated placenta to the uterus or still in gestational immunomodulatory responses. Moreover, it reinforces the possibility of specific activities for Mif at the maternal fetal interface.

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The peritoneal cavity (PerC) is a singular compartment where many cell populations reside and interact. Despite the widely adopted experimental approach of intraperitoneal (i.p.) inoculation, little is known about the behavior of the different cell populations within the PerC. To evaluate the dynamics of peritoneal macrophage (Mempty set) subsets, namely small peritoneal Mempty set (SPM) and large peritoneal Mempty set (LPM), in response to infectious stimuli, C57BL/6 mice were injected i.p. with zymosan or Trypanosoma cruzi. These conditions resulted in the marked modification of the PerC myelo-monocytic compartment characterized by the disappearance of LPM and the accumulation of SPM and monocytes. In parallel, adherent cells isolated from stimulated PerC displayed reduced staining for beta-galactosidase, a biomarker for senescence. Further, the adherent cells showed increased nitric oxide (NO) and higher frequency of IL-12-producing cells in response to subsequent LPS and IFN-gamma stimulation. Among myelo-monocytic cells, SPM rather than LPM or monocytes, appear to be the central effectors of the activated PerC; they display higher phagocytic activity and are the main source of IL-12. Thus, our data provide a first demonstration of the consequences of the dynamics between peritoneal Mempty set subpopulations by showing that substitution of LPM by a robust SPM and monocytes in response to infectious stimuli greatly improves PerC effector activity.

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Plasmodium species are the causative agents of malaria, the most devastating insect-borne parasite of human populations. Finding and developing new drugs for malaria treatment and prevention is the goal of much research. Angiotensins I and II (ang I and ang II) and six synthetic related peptides designated Vaniceres 1-6 (VC1-VC6) were assayed in vivo and in vitro for their effects on the development of the avian parasite, Plasmodium gallinaceum. Ang II and VC5 injected into the thoraces of the insects reduced mean intensities of infection in the mosquito salivary glands by 88% and 76%, respectively. Although the mechanism(s) of action is not completely understood, we have demonstrated that these peptides disrupt selectively the P. gallinaceum cell membrane. Additionally, incubation in vitro of sporozoites with VC5 reduced the infectivity of the parasites to their vertebrate host. VC5 has no observable agonist effects on vertebrates, and this makes it a promising drug for malaria prevention and chemotherapy.

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It is well known that resonance can be induced by external noise or diversity. Here we show that resonance can be induced even by a phase disorder in coupled excitable neurons with subthreshold activity. In contrast to the case of identical phase, we find that phase disorder plays an active role in enhancing neuronal activity. We also uncover that the presence of phase disorder can induce a double resonance phenomenon: phase disorder and coupling strength both can enhance neuronal firing activity. A physical theory is formulated to help understand the mechanism behind this double resonance phenomenon.