Origem física das curvas sigmoidais respiratórias pressão-volume: recrutamento alveolar e elasticidade não-linear

An important unsolved problem in medical science concerns the physical origin of the sigmoidal shape of pressure volume curves of healthy (and some unhealthy) lungs. Such difficulties are expected because the lung, which is the most important structure in the respiratory system, is extremely complex. Its rheological properties are unknown and seem to depend on phenomena occurring from the alveolar scale up to the thoracic scale. Conventional wisdom holds that linear response, i.e., Hooke s law, together with alveolar overdistention, play a dominant role in respiration, but such assumptions cannot explainthe crucial empirical sigmoidal shape of the curves. In this doctorate thesis, we propose an alternative theory to solve this problem, based on the alveolar recruitment together with the nonlinear elasticity of the alveoli. This theory suggests that recruitment may be the predominant factor shaping these curves in the entire range of pressures normally employed in experiments. The proposed model correctly predicts the observed sigmoidal pressure volume curves, allowing us to discuss adequately the importance of this result, as well as its implications for medical practice

Influencia do meloxicam sobre a perda ossea alveolar em periodontite experimental: avaliaçao histometrica em ratos

GURGEL, Bruno Cesar de vasconcelos.Influencia do meloxicam sobre a perda ossea alveolar em periodontite experimental: avaliaçao histometrica em ratos. 2003.97f. Dissertaçao (Mestrado) - Universidade Estadual de Campinas. Faculdade de Odontologia de Piracicaba. Piracicaba, 2003. Disponivel em: de=vtls000293698>. Acesso em: 04 out. 2010.

Influencia do meloxicam sobre a perda ossea alveolar em periodontite experimental: avaliaçao histometrica em ratos

GURGEL, Bruno Cesar de vasconcelos.Influencia do meloxicam sobre a perda ossea alveolar em periodontite experimental: avaliaçao histometrica em ratos. 2003.97f. Dissertaçao (Mestrado) - Universidade Estadual de Campinas. Faculdade de Odontologia de Piracicaba. Piracicaba, 2003. Disponivel em: de=vtls000293698>. Acesso em: 04 out. 2010.

Lesões orais com potencial de malignização: análise clínica e morfológica de 205 casos

Silveira , E. J. D. et al. Lesões orais com potencial de malignização: análise clínica e morfológica de 205 casos. J. Bras. Patol. Med. Lab., v. 45, n. 3, p. 233-238, jun 2009. ISBN 1676-2444.

Lesões pulmonares provocadas pela nicotina por via subcutânea em ratos.

RESUMO: Objetivo: Estudo com o objetivo de observar a influência da nicotina, aplicada pela via subcutânea, em pulmões de ratos. Métodos: Foram utilizados 20 ratos Wistar pesando 235±35g, separados aleatoriamente em 2 grupos iguais. O grupo I (n=10) recebeu nicotina na dose de 2 mg/ Kg/dia pela via subcutânea durante 20 dias e o grupo II (n=10) recebeu placebo pela mesma via de administração. Resultados: Os resultados mostraram que no grupo I ocorreu broncopneumonia em 3 (30%) ratos, leucocitose alveolar em 10 (100%) e leucocitose septal em 7 (70%). Atelectasia foi encontrada em 2 (20%). Transformados em escores, os dados totalizaram 52 pontos. Os escores das alterações observadas nos pulmões do grupo II atingiram 11 pontos (p<0,05). Conclusão: Os dados permitiram concluir que o uso da nicotina por via subcutânea contribuiu para o aparecimento de lesões pulmonares em ratos, em número e intensidade significativamente maiores do que nos animais considerados controles.

Lesões pulmonares provocadas pela nicotina por via subcutânea em ratos

Objetivo: Estudo com o objetivo de observar a influência da nicotina, aplicada pela via subcutânea, em pulmões de ratos. Métodos: Foram utilizados 20 ratos Wistar pesando 235±35g, separados aleatoriamente em 2 grupos iguais. O grupo I (n=10) recebeu nicotina na dose de 2 mg/Kg/dia pela via subcutânea durante 20 dias e o grupo II (n=10) recebeu placebo pela mesma via de administração. Resultados: Os resultados mostraram que no grupo I ocorreu broncopneumonia em 3 (30%) ratos, leucocitose alveolar em 10 (100%) e leucocitose septal em 7 (70%). Atelectasia foi encontrada em 2 (20%). Transformados em escores, os dados totalizaram 52 pontos. Os escores das alterações observadas nos pulmões do grupo II atingiram 11 pontos (p<0,05). Conclusão: Os dados permitiram concluir que o uso da nicotina por via subcutânea contribuiu para o aparecimento de lesões pulmonares em ratos, em número e intensidade significativamente maiores do que nos animais considerados controles

Modulação da expressão da proteína XPA em resposta ao tratamento com azul de metileno fotossensibilizado

Reactive oxygen species (ROS) are produced by aerobic metabolism and react with biomolecules, such as lipids, proteins and DNA. In high concentration, they lead to oxidative stress. Among ROS, singlet oxygen (1O2) is one of the main ROS involved in oxidative stress and is one of the most reactive forms of molecular oxygen. The exposure of some dyes, such as methylene blue (MB) to light (MB+VL), is able to generate 1O2 and it is the principle involved in photodynamic therapy (PDT). 1O2 e other ROS have caused toxic and carcinogenic effects and have been associated with ageing, neurodegenerative diseases and cancer. Oxidative DNA damage is mainly repaired by base excision repair (BER) pathway. However, recent studies have observed the involvement of nucleotide excision repair (NER) factors in the repair of this type of injury. One of these factors is the Xeroderma Pigmentosum Complementation Group A (XPA) protein, which acts with other proteins in DNA damage recognition and in the recruitment of other repair factors. Moreover, oxidative agents such as 1O2 can induce gene expression. In this context, this study aimed at evaluating the response of XPA-deficient cells after treatment with photosensitized MB. For this purpose, we analyzed the cell viability and occurrence of oxidative DNA damage in cells lines proficient and deficient in XPA after treatment with MB+VL, and evaluated the expression of this enzyme in proficient and complemented cells. Our results indicate an increased resistance to treatment of complemented cells and a higher level of oxidative damage in the deficient cell lines. Furthermore, the treatment was able to modulate the XPA expression up to 24 hours later. These results indicate a direct evidence for the involvement of NER enzymes in the repair of oxidative damage. Besides, a better understanding of the effects of PDT on the induction of gene expression could be provided

Efeito anti-inflamatório do heparinóide isolado do camarão Litopenaeus vannamei sobre a peritonite aguda

In recent years the heparin has been the subject of several studies that aim to expand its use as a therapeutic agent, due to its ability to modulate the activity of various proteins that play important roles in the regulation of pathophysiological processes. In several experiments and preclinical trials, heparin has demonstrated an anti-inflammatory role. However, its clinical use is limited, due to its strong anticoagulant activity and hemorrhagic complications. For this reason, considerable efforts have been employed in discovery of heparin analogous (heparinoid) with reduced side effects, that retain the anti-inflammatory properties of heparin. In this context, a heparinoid obtained from the head of Litopenaeus vannamei shrimp, which presents a structural similarity to heparin, showed, in previous studies, anti-inflammatory activity in a model of acute peritonitis with reduced anticoagulant effect in vitro and low hemorrhagic activity. Thus, the present work had as objective to evaluate the effect the heparinoid of the cephalothorax of gray shrimp on the acute inflammatory response in different times (3 or 6 hours after the induction of inflammatory stimulus), using the model of acute peritonitis induced in mice. It was also analyzed the HL effect over the activity of elastase, an enzyme involved in leukocyte recruitment. Furthermore to check if the different doses of heparin and heparinoid change the hemostatic balance in vivo, was assessed the effect of these compounds on the plasma clotting time in animals submitted to inflammation. The results show that in 3 hours, all doses of heparinoid were able to prevent efficiently in the acute inflammatory process without any anticoagulant effects, unlike the extrapolation dose of heparin, which has induced a large hemorrhage due its high anticoagulant activity. However, 6 hours after induction of inflammation, only the dosages of 0.1 and 1.0 μg/Kg of heparin and 1.0 μg/Kg of heparinoid kept anti-migratory effect, without changing of the hemostatic balance. These results indicate that the anti-migratory effect of theses compounds depends on the dosage and time of inflammatory stimulus. The HL and heparin were also able to inhibit the activity of the enzyme elastase. The discovery of this bioactive compound in the cephalothorax of shrimps can arouse great interest in biotechnology, since this compound could be useful as a structural model interesting for the development of new therapeutic agents for peritonitis

Bioecologia da ictiofauna marinha descartada pelo arrasto camaroeiro em praias da Bacia Potiguar, Brasil

The composition of ichthyofauna discarded by trawling shrimping, their reproductive status and feeding ecology were studied on the beaches of Basin Rio Grande do Norte, Brazil. Fish were collected monthly in the year of 2012. During biometrics, portions of the digestive tract and of gonads were removed, fixed in formalin 10% and Bouin, respectively, for be submitted to histological processing by the techniques of hematoxylin-eosin. Stomach content analyzes were performed using the methods of Frequency of Occurrence and Volumetric and was calculated the repletion index. Throughout the study period were recorded a total of 49 species. The fish assemblages differed between sections monitoring, with the highest abundance, biomass and indices of richness and diversity in sections B, D and C. Already the excerpt A, showed higher values for dominance and equitability. In the cluster analysis according to the faunal similarity was observed the formation of three groups: group I formed by excerpts B and D, group II by excerpt C and group III formed by excerpt A. The assessment of reproductive stage revealed that the fish assemblages discarded by trawling are composed mainly of juveniles. Regarding the feeding ecology, the species Larimus breviceps, Menticirrhus littoralis and Pomadasys corvinaeformis characterized as carnivorous with tendency to carcinofagia. Already Conodon nobilis characterized as carnivorous with tendency to piscivory, but all proved generalist-opportunistic with increase of feeding activity during drought. The dendrogram of grouping of the species developed based on the food items used shows the formation of four groups: Group I consists of species that feed mainly of "gastropod" and "sediment"; group II of "teleost fish"; the group III of "crustacea" and group IV of "echinodermata" and "bivalve". The anatomical and histological characteristics of the digestive tract were consistent with the dietary habits of the analyzed species. In this context, the Costa Branca of Rio Grande do Norte can be considered a feeding site and recruitment for juveniles, which, opportunistically, utilize resources associated with the background

Avaliação eletromiográfica dos músculos do assoalho pélvico na síndrome dos ovários policísticos

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Sobrevivência e tamanho populacional do Tiê-preto Tachyphonus Rufus (aves: thraupidae) em fragmento de restinga no extremo Norte da Mata Atlântica

For a long time, we believed in the pattern that tropical and south hemisphere species have high survival. Nowadays results began to contradict this pattern, indicating the need for further studies. Despite the advanced state of the study of bird population parameters, little is known about their variation throughout the year and the factors affecting them. Reproduction, for example, is one factor that may alter adult survival rates, because during this process the breeding pair allocates resources to maintain itself to maintain offspring, making itself more susceptible to diseases and predation. The aim of this study was to estimate survival and population size of a Central and South America passerine, Tachyphonus rufus (Boddaert, 1783), testing hypotheses about the factors that define these parameters. We performed data collection between Nov/2010 and ago/2012 in 12 ha plot, in a fragment of Atlantic Forest in northeastern Brazil. We used capture-mark-recapture methods to generate estimates using Closed Design Robust model in the program MARK. We generated Multi-state models to test some assumptions inherent to Closed Robust Design. The influence of co-variables (time, rain and reproductive cycle) and the effect of transient individuals were measured. Capture, recapture and apparent survival parameters were defined by reproductive cycle, while temporary dispersal was influence by rain. The estimates showed a higher apparent survival during the non-breeding period (92% ± 1%) than during breeding (40% ± 9%), revealing a cost of reproduction and suggesting a trade-off between surviving and reproducing. The low annual survival observed (34%) did not corroborate the pattern of high rates expected for a tropical bird. The largest population size was estimated to be 56 individuals in Nov/11, explained by high recruitment of juveniles, while the lowest observed in May/12: 10 individuals, probably as a result of massive influx of competitor species. Results from this study add to the growing literature on life history of Neotropical species. We encourage studies like this especially in Brazil, where there are few information, and suggest that covariates related to habitat quality and environmental changes should be tested, so that we can generate increasingly reliable models

Desenvolvimento nacional, desenvolvimento regional e moeda: notas teóricas à luz da economia política do desenvolvimento

This work analyses the ability of National States and regions have to formulations development strategies. Redeeming the initial development concept as a conflictual process, the hypothesis is that it presents internal and external constraints, as the latter have a higher preponderance, revealed the role played by money. In this case, one can point to as sub-hypothesis that the growth models with external constraint, mainly through the balance of payments, may illustrate the fact that countries are subject to international economic interactions that limit the possibility of bringing acylating strategies well successful in overcoming backwardness. For the specific case of regions, indicates that the external constraint remains an element of embarrassment for regional development, but redeems itself the center-periphery relations in this context to discuss the role of monetary and financial system as an explanation for the disparities regional income. On the domestic front, we highlight the importance of social structures of accumulation as an element of internal cohesion necessary to achieve successful development trajectories. It points also to the importance of the State in the process rescuing some of the main theoretical contributions of the political economy of development, incorporating the concept of globalization on theoretical frameworks presented. This construction where development depends on the actions of external and internal conditions, where money plays a key role as a guideline for reflections on regional development. The attempt was to transplant our considerations on the general development to address the case of regions. Finally, we conclude by greater confidence in the hypothesis and sub-hypotheses of departure, which led to propositions of economic policies

Avaliação muscular respiratória: adaptação do mano vacuômetro nacional para a avaliação da pressão inspiratória nasal e nível de intensidade da ventilação voluntária máxima em sujeitos saudáveis

The clinical importance of evaluating the respiratory muscles with a variety of tests has been proposed by several studies, once that the combination of several tests would allow a better diagnosis and therefore, a better clinical follow of disorders of the respiratory muscles. This study aimed to evaluate the feasibility of adapting a national electronic manovacuometer to measure the nasal inspiratory pressure (study 1) and analyze the level of load intensity of maximum voluntary ventilation, as well as the variables that may influence this maneuver in healthy subjects (study 2). We studied 20 healthy subjects by a random evaluation of two measures of SNIP in different equipments: a national and an imported. In study 2 it was analyzed the intensity of the load of MVV test, change in pressure developed during the maneuver, the possible differences between genders, and the correlations between the flow developed in the test and the result of MVV. In study 1 it was found the average for both measures of nasal inspiratory pressures: 125 ± 42.4 cmH2O for the imported equipment and 131.7 ± 28.7 cmH2O for the national one. Pearson analysis showed a significant correlation between the average, with a coefficient r = 0.63. The average values showed no significant differences evaluated by paired t test (p> 0.05). In the Bland-Altman analysis it was found a BIAS = 7 cmH2O, SD 32.9 and a confidence interval of - 57.5 cmH2O up to 71.5 cmH2O. In the second study it was found significant differences between the genders in the air volume moved, being higher in males 150.9 ± 13.1 l / min vs 118.5 ± 15.7 L / min for (p = 0.0002, 95% CI 44.85 to 20:05). Regarding the inspiratory and expiratory loading, they were significantly higher in men than in women, peak inspiratory pressure (34.7 ± 5.3 cmH2O vs 19.5 ± 4.2 cmH2O, 95% CI - 18.0 to -12.3, p <0.0001), peak expiratory (33.8 vs. 23.1 ± 5.9 cmH2O ± 5.4 cmH2O, 95% CI -17.1 to - 4.6, p <0.0001), and the delta pressure (59.7 ± 10 cmH2O vs 36.8 ± 8.3 cmH2O, 95% CI 14.5 to 31.2, p <0.0002). The Pearson correlation showed that the flow generated by the maneuver is strongly correlated with the delta-expiratory pressure / inspiratory (r2= 0.83,R = 0.91, 95%IC 0.72 a 0.97 e p< 0.0001).Through these results we suggest that the national electronic manovacuometer is feasible and safe to perform the sniff test in healthy subjects. For the MVV, there are differences between the genders in the intensity of pressure developed during the maneuver. We found a load intensity considered low during the MVV, and found a strong correlation between the flow generated in the test and the delta pressure expiratory / inspiratory

Avaliação da cinemática do complexo tóracoabdominal durante repouso e endurance muscular respiratória em obesos

Background: Obesity may affect the respiratory system, causing changes in respiratory function and in the pulmonary volumes and flows. Objectives: To evaluate the influence of obesity in the movement of thoracoabdominal complex at rest and during maximal voluntary ventilation (MVV), and the contribution between the different compartments of this complex and the volume changes of chest wall between obese and non-obese patients. Materials and Methods: We studied 16 patients divided into two groups: the obese group (n = 8) and group non-obese (n = 8). The two groups were homogeneous in terms of spirometric characteristics (FVC mean: 4.97 ± 0.6 L - 92.91 ± 10.17% predicted, and 4.52 ± 0.6 L - 93.59 ± 8.05%), age 25.6 ± 5.0 and 26.8 ± 4.9 years, in non-obese and obese respectively. BMI was 24.93 ± 3.0 and 39.18 ± 4.3 kg/m2 in the groups investigated. All subjects performed breathing calm and slow and maneuver MVV, during registration for optoelectronic plethysmography. Statistical analysis: we used the unpaired t test and Mann-Whitney. Results: Obese individuals had a lower percentage contribution of the rib cage abdominal (RCa) during breathing at rest and VVM. The variation of end expiratory (EELV) and end inspiratory (EILV) lung volumes were lower in obese subjects. It has been found asynchrony and higher distortion between compartments of thoracoabdominal complex in obese subjects when compared to non-obese. Conclusions: Central obesity impairs the ventilation lung, reducing to adaptation efforts and increasing the ventilatory work

Influência do método pilates na força e atividade elétrica dos músculos respiratórios de idosas - ensaio clínico controlado randomizado

The reduction of physiological capacity present in the process of aging causes a marked decline in lung function. The exercise does promote several positive changes in the physical health of people and protect the cardiorespiratory function. The aim of this study was to investigate the effects of a program of Pilates exercices on the strengh and electrical activity of respiratory muscles of elderly. This is a randomized, controlled clinical trial, evaluating 33 elderly aged 65 and 80 (70.88 ± 4.32), healthy, sedentary, without cognitive impairment and able the practice physical activity. The sample was divided into two groups, one experimental group with 16 elderly women who did Pilates exercises and a control group (17) that was not submitted to the exercises, but received educational booklets on aging and health care. The elderly were evaluated initially and after a period of three months, taking into account the Maximal Inspiratory Pressure (MIP) and Maximal Expiratory Pressure (MEP), obtained by Manovacuometry and intensity of EMG activity was measured using the values of Root Mean Square (RMS) for the diaphragm and rectus abdominis muscles, during the course of diaphragmatic breathing and MIP maneuver. Data were analyzed using SPSS version 17.0. For all tests, we used a significance level or p value < 0.05 and confidence interval 95%. RMS in diaphragm and rectus abdominis muscles in both tests increased, but the data were significant for the rectus abdominis during diaphragmatic breathing (p = 0.03) and the diaphragm during the MIP maneuver (p = 0.01). There was no significant variation of the MIP and MEP. Pilates exercises were responsible for increasing the electrical activation of the diaphragm and rectus abdominis muscles in a group of healthy elderly, but had no influence on changes in strength of respiratory muscles