14 resultados para Reaction to diversity
em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo
Resumo:
Objectives: This study evaluated subcutaneous tissue response to Aroeira (Myracrodruon urundeuva) extract employing edemogenic and histological analyses. Material and methods: Test groups consisted of aqueous and ethanolic Aroeira extracts and saline (control). For groups consisted of aqueous and ethanolic Aroeira extracts and saline Blue. After 30 min, the extracts and saline were injected on the dorsum of the rats, which were then sacrificed after 3 and 6 h. Readings were performed in a spectrophotometer. For subcutaneous implantation, 30 rats received a polyethylene tube containing the extracts on their dorsum and then they were killed after 7 and 28 days. The samples were processed for histological analysis and evaluated with a light microscope. The inflammatory infiltrate was quantified. Results: There were no statistically significant differences between aqueous extract and saline groups in relation to edema quantification in the different periods (p > 0.05). Ethanolic solution resulted in more edema independently of the experimental period (p < 0.05). Histological analysis showed similar results on the 7-day period for the 3 groups. There was a notable reduction on inflammatory cell number for saline and aqueous extract groups at 28 days. Conclusion: The aqueous extract showed biocompatible properties similar to those of saline.
Resumo:
The extent to which the hypothalamic-pituitary-adrenal axis is activated by short-term and long-term consequences of stress is still open to investigation. This study aimed to determine (i) the correlation between plasma corticosterone and exploratory behavior exhibited by rats subjected to the elevated plus maze (EPM) following different periods of social isolation, (ii) the effects of the corticosterone synthesis blocker, metyrapone, on the behavioral consequences of isolation, and (iii) whether corticosterone produces its effects through an action on the anterior cingulate cortex, area 1 (Cg1). Rats were subjected to 30-min, 2-h, 24-h, or 7-day isolation periods before EPM exposure and plasma corticosterone assessments. Isolation for longer periods of time produced greater anxiogenic-like effects on the EPM. However, stretched attend posture (SAP) and plasma corticosterone concentrations were increased significantly after 30 min of isolation. Among all of the behavioral categories measured in the EPM, only SAP positively correlated with plasma corticosterone. Metyrapone injected prior to the 24 h isolation period reversed the anxiogenic effects of isolation. Moreover, corticosterone injected into the Cg1 produced a selective increase in SAP. These findings indicate that risk assessment behavior induced by the action of corticosterone on Cg1 neurons initiates a cascade of defensive responses during exposure to stressors.
Resumo:
Leprosy is an infectious disease caused by Mycobacterium leprae. The polymerase chain reaction (PCR) has been applied to detect M. leprae in different clinical samples and urine seems to be attractive for this purpose. PCR was used to improve the sensitivity for diagnosing leprosy by amplifying a 151-bp PCR fragment of the M. leprae pra gene (PCR-Pra) in urine samples. Seventy-three leprosy patients (39 males and 34 females, 14 to 78 years old) were selected for leprosy diagnosis at a reference laboratory in Maringa, PR, Brazil. Of these, 36 were under anti-leprosy multidrug therapy with dapsone and rifampicin for tuberculoid (TT) and dapsone, rifampicin and clofazimine for borderline (BB) and lepromatous (LL) forms. The control group contained 50 healthy individuals without any clinical history of leprosy. DNA isolated from leprosy patients' urine samples was successfully amplified by PCR-Pra in 46.6% (34/73) of the cases. The positivity of PCR-Pra for patients with the TT form was 75% for both patients under treatment and non-treated patients (P = 0.1306). In patients with the LL form, PCR-Pra positivity was 52 and 30% for patients under treatment and non-treated patients, respectively (P = 0.2386). PCR-Pra showed a statistically significant difference in detecting M. leprae between the TT and LL forms of leprosy in patients under treatment (P = 0.0033). Although the current study showed that the proposed PCR-Pra has some limitations in the detection of M. leprae, this method has the potential to be a useful tool for leprosy diagnosis mainly in TT leprosy where the AFB slit-skin smear is always negative.
Resumo:
Although mangroves represent ecosystems of global importance, the genetic diversity and abundance of functional genes that are key to their functioning scarcely have been explored. Here, we present a survey based on the nifH gene across transects of sediments of two mangrove systems located along the coast line of Sao Paulo state (Brazil) which differed by degree of disturbance, i.e., an oil-spill-affected and an unaffected mangrove. The diazotrophic communities were assessed by denaturing gradient gel electrophoresis (DGGE), quantitative PCR (qPCR), and clone libraries. The nifH gene abundance was similar across the two mangrove sediment systems, as evidenced by qPCR. However, the nifH-based PCR-DGGE profiles revealed clear differences between the mangroves. Moreover, shifts in the nifH gene diversities were noted along the land-sea transect within the previously oiled mangrove. The nifH gene diversity depicted the presence of nitrogen-fixing bacteria affiliated with a wide range of taxa, encompassing members of the Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria, Firmicutes, and also a group of anaerobic sulfate-reducing bacteria. We also detected a unique mangrove-specific cluster of sequences denoted Mgv-nifH. Our results indicate that nitrogen-fixing bacterial guilds can be partially endemic to mangroves, and these communities are modulated by oil contamination, which has important implications for conservation strategies.
Resumo:
Human Parvovirus B19 (B19V) is a recognized cause of life-threatening conditions among patients with hemoglobinopathies. This study investigates B19V infection in patients with sickle cell disease and beta-thalassemia using different experimental approaches. A total of 183 individuals (144 with sickle cell disease and 39 with beta-thalassemia major) and 100 healthy blood donors were examined for B19V using anti-B19V IgG enzyme immunoassay, quantitative PCR, DNA sequencing, and phylogenetic analysis. Viremia was documented in 18.6% of patients and 1% of donors, and was generally characterized by low viral load (VL); however, acute infections were also observed. Anti-B19V IgG was detected in 65.9% of patients with sickle cell disease and in 60% of donors, whereas the patients with thalassemia exhibited relatively low seroreactivity. The seroprevalence varied among the different age groups. In patients, it progressively increased with age, whereas in donors it reached a plateau. Based on partial NS1 fragments, all isolates detected were classified as subgenotype 1A with a tendency to elicit genetically complex infections. Interestingly, quasispecies occurred in the plasma of not only patients but also donors with even higher heterogeneity. The partial NS1 sequence examined did not exhibit positive selection. Quantitation of B19V with a conservative probe is a technically and practically useful approach. The extensive spread of B19V subgenotype 1A in patients and donors and its recent introduction into the countryside of the Sao Paulo State, Brazil were demonstrated; however, it is difficult to establish a relationship between viral sequences and the clinical outcomes of the infection. J. Med. Virol. 84:16521665, 2012. (c) 2012 Wiley Periodicals, Inc.
Resumo:
The ventilation rate (VR) of an ostariophysan fish, the speckled catfish Pseudoplaty - stoma coruscans, exposed to a chemical alarm cue was measured in the present study in multiple contexts. The influence of the extraction techniques, skin donor food intake and quantity of the alarm cue (skin extract) on this autonomic response was considered. Overall, the catfish VR decreased significantly when exposed to the skin extract (chemical alarm cue) compared with exposure to distilled water (control). No effect of the extraction technique was found. Increasing doses of the skin extract induced a VR reduction of similar magnitude. However, extract obtained from daily-fed fish induced a significant decrease in the VR, whereas extract obtained from foodrestricted fish did not induce any change in the VR. Thus, food intake was associated with the production of a more easily recognizable alarm cue in the speckled catfish. Interestingly, this effect was not related to differences in the number of club cells in the donor catfish epidermis. Dashing, or rapid swimming, a normal component of the alarm response in fish, including this catfish species, was not observed here, and hypoventilation was always associated with no swimming reaction. Together, these results suggest that hypoventilation is a reaction to a chemical alarm cue, likely resulting in improved crypsis, causing the fish to become less easily perceived by a potential predator that usually strikes prey in response to movement.
Resumo:
The transposition of the São Francisco River is considered one of the greatest engineering works in Brazil of all time since it will cross an extensive agricultural region of continental dimensions, involving environmental impacts, water, soil, irrigation, water payment and other multidisciplinary themes. Taking into account its importance, this subject was incorporated into a discipline of UFSCar (Federal University of São Carlos - Brazil) named "Pollution and Environmental Impacts". It was noted strong reaction against the project, even before the presentation. To allow a critical analysis, the first objective was to compile the main technical data and environmental impacts. The second objective was to detect the three most important aspects that cause reaction, concluding for the following reasons: assumption that the volume of water to be transferred was much greater than it actually is proposed in the project; lack of knowledge about similar project already done in Brazil; the idea that the artificial canal to be built was much broader than that proposed by the project. The participants' opinion about "volume to be transferred" was raised quantitatively four times: 2-undergraduate students; 1-graduate; 1-outside community. The average resulted 14 times larger than that proposed in the project, significant according to t-test. It was concluded that the reaction to water transfer project is due in part to the ignorance combined with a preconceived idea that tend to overestimate the magnitude of environmental impacts.
Resumo:
Discussions about the new meaning of citizenship, valuing differences and respecting knowledge diversity bring the question of how public policies can be locally rooted to ensure access to diversity. This is evident when we deal with health policies, where the interaction between implementers and beneficiaries is essential to understand the results of the policy. The Family Health Program (FHP) has tried to change the relationship between state and society, bringing health professionals with the daily experienced by the users where there is (re) production of the components that lead to insecurity, poor health and disease. To analyse this kind of policy we must take into account the interaction processes and the practices of the actors involved in the FHP implementation. This article aims to analyze the role of Health Communitarian Agents (HCA) as FHP implementers. Through ethnographic research followed the practices of ACS in different cities, we seek to understand how they deal with their different knowledge, enable and disable referrals and adapt action to enact the program. We want to understand how they use mediations and interactions in their practices and built policies locally rooted, constructing alternative ways to implement these policies.
Resumo:
Prosthetic meshes are commonly used to correct abdominal wall defects. However, the inflammatory reaction induced by these devices in the peritoneum is not completely understood. We hypothesized that nitric oxide (NO), produced by nitric oxide synthase 2 (NOS2) may modulate the response induced by mesh implants in the abdominal wall and, consequently, affect the outcome of the surgical procedure. Polypropylene meshes were implanted in the peritoneal side of the abdominal wall in wild-type and NOS2-deficient (NOS2(-/-)) mice. After 15 days tissues around the mesh implant were collected, and inflammatory markers (the cytokine interleukin 1 beta (IL-1 beta) and NO) and tissue remodeling (collagen and metalloproteinases (MMP) 2 and 9) were analyzed. The lack of NOS2-derived NO induced a higher incidence of visceral adhesions at the mesh implantation site compared with wild-type mice that underwent the same procedure (P < 0.05). Additionally, higher levels of IL-1 beta were present in the mesh-implanted NOS2(-/-) animals compared with control and wild-type mice. Mesh implantation induced collagen I and III deposition, but in smaller amounts in NOS2(-/-) mice. MMP-9 activity after the surgical procedure was similarly increased in both groups. Conversely, MMP-2 activity was unchanged in mesh-implanted wild-type mice, but was significantly increased in NOS2(-/-) mice (P < 0.01), due to decreased S-nitrosylation of the enzyme in these animals. We conclude that NOS2-derived NO is crucial for an adequate response to and integration of polypropylene mesh implants in the peritoneum. NO deficiency results in a prolonged inflammatory reaction to the mesh implant, and reduced collagen deposition may contribute to an increased incidence of visceral adhesions. (C) 2011 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
Resumo:
Monomers based on plant oil derivatives bearing furan heterocycles appended through thiol-ene click chemistry were prepared and, subsequently, polymerized via a second type of click reaction, i. e. the Diels-Alder (DA) polycondensation between furan and maleimide complementary moieties. Two basic approaches were considered for these DA polymerizations, namely (i) the use of monomers with two terminal furan rings in conjunction with bismaleimides (AA + BB systems) and (ii) the use of a protected AB monomer incorporating both furan and maleimide end groups. This study clearly showed that both strategies were successful, albeit with different outcomes, in terms of the nature of the ensuing products. The application of the retro-DA reaction to these polymers confirmed their thermoreversible character, i. e. the clean-cut return to their respective starting monomers, opening the way to original macromolecular materials with interesting applications, like mendability and recyclability.
Resumo:
Cancer cachexia is a multifaceted syndrome whose aetiology is extremely complex and is directly related to poor patient prognosis and survival. Changes in lipid metabolism in cancer cachexia result in marked reduction of total fat mass, increased lipolysis, total oxidation of fatty acids, hyperlipidaemia, hypertriglyceridaemia, and hypercholesterolaemia. These changes are believed to be induced by inflammatory mediators, such as tumour necrosis factor-alpha (TNF-alpha) and other factors. Attention has recently been drawn to the current theory that cachexia is a chronic inflammatory state, mainly caused by the host's reaction to the tumour. Changes in expression of numerous inflammatory mediators, notably in white adipose tissue (WAT), may trigger several changes in WAT homeostasis. The inhibition of adipocyte differentiation by PPAR gamma is paralleled by the appearance of smaller adipocytes, which may partially account for the inhibitory effect of PPAR gamma on inflammatory gene expression. Furthermore, inflammatory modulation and/or inhibition seems to be dependent on the IKK/NF-kappa B pathway, suggesting that a possible interaction between NF-kappa B and PPAR gamma is required to modulate WAT inflammation induced by cancer cachexia. In this article, current literature on the possible mechanisms of NF-kappa B and PPAR gamma regulation of WAT cells during cancer cachexia are discussed. This review aims to assess the role of a possible interaction between NF-kappa B and PPAR gamma in the setting of cancer cachexia as well as its significant role as a potential modulator of chronic inflammation that could be explored therapeutically. Crown Copyright (C) 2011 Published by Elsevier Ltd. All rights reserved.
Resumo:
This article characterizes hypersensitivity reactions during anesthetic-surgical procedures. This integrative literature review was conducted in the LILACS, CINAHL, COCHRANE and MEDLINE databases including papers published from 1966 to September 2011. A total of 17 case reports, two prevalence studies and one cohort study were identified. Latex reactions were mainly type III and the primary source of intraoperative reaction was latex gloves. The average time for clinical manifestation was 59.8 minutes after anesthetic induction; 44.4% of patients reported a reaction to latex at the pre-anesthetic evaluation. It was determined that the history of allergic reactions to latex obtained in the pre-anesthetic evaluation does not ensure the safety of patients if the staff is inattentive to the severity of the issue. There is also a tendency to initially attribute the anaphylactic event to the anesthetic drugs.
Resumo:
The conjugated frustrated phosphane/borane Lewis pairs formed by 1,1-carboboration of a substituted diphenylphosphino acetylene, undergo a synergistic 1,1-addition reaction to n-butyl isocyanide with formation of new B-C and P-C bonds to the former isonitrile carbon atom. Using tert-butyl isocyanide dynamic behaviour between the isocyanide-[B] adduct and the 1,1-addition product formation was observed in solution. The different modes of isocyanide binding to the FLPs in the solid state were characterized using X-ray crystal structure analyses and comprehensive 11B and 31P solid-state magicangle- spinning (MAS-) NMR experiments. The free FLP, the Lewis adduct at the borane group, and the cyclic product resulting from isocyanide addition to both reaction centers, can be differentiated via 11B and 31P isotropic chemical shifts, 11B nuclear electric quadrupole coupling constants, isotropic indirect 11B-31P spin-spin coupling constants, and 11B...31P internuclear distances measured by rotational echo double resonance.
Resumo:
The study of Antarctic archaeal communities adds information on the biogeography of this group and helps understanding the dynamics of biogenic methane production in such extreme habitats. Molecular methods were combined to methane flux determinations in Martel Inlet, Admiralty Bay, to assess archaeal diversity, to obtain information about contribution of the area to atmospheric methane budget and to detect possible interferences of the Antarctic Brazilian Station Comandante Ferraz (EACF) wastewater discharge on local archaeal communities and methane emissions. Methane fluxes in Martel Inlet ranged from 3.2 to 117.9 mu mol CH(4) m(-2) d(-1), with an average of 51.3 +/- 8.5 mu mol CH(4) m(-2) d(-1) and a median of 57.6 mu mol CH(4) m(-2)d(-1). However, three negative fluxes averaging -11.3 mu mol CH(4) m(-2) d(-1) were detected in MacKellar Inlet, indicating that Admiralty Bay can be either a source or sink of atmospheric methane. Denaturing gradient gel electrophoresis (DGGE) showed that archaeal communities at EACF varied with depth and formed a group separated from the reference sites. Granulometric analysis indicated that differences observed may be mostly related to sediment type. However, an influence of wastewater input could not be discarded, since higher methane fluxes were found at CF site. suggesting stimulation of local methanogenesis. DGGE profile of the wastewater sample grouped separated from all other samples, suggesting that methanogenesis stimulation may be due to changes in environmental conditions rather than to the input of allochtonous species from the wastewater. 16S ribosomal DNA clone libraries analysis showed that all wastewater sequences were related to known methanogenic groups belonging to the hydrogenotrophic genera Methanobacterium and Methanobrevibacter and the aceticlastic genus Methanosaeta. EACF and Botany Point sediment clone libraries retrieved only groups of uncultivated Archaea, with predominance of Crenarchaeota representatives (MCG, MG1, MBG-B, MBG-C and MHVG groups). Euryarchaeota sequences found were mostly related to the LDS and RC-V groups, but MBG-D and DHVE-5 were also present. No representatives of cultivated methanogenic groups were found, but coverage estimates suggest that a higher number of clones would have to be analyzed in order to cover the greater archaeal diversity of Martel Inlet sediment. Nevertheless, the analysis of the libraries revealed groups not commonly found by other authors in Antarctic habitats and also indicated the presence of groups of uncultivated archaea previously associated to methane rich environments or to the methane cycle. (C) 2010 Elsevier Ltd. All rights reserved.