Influence of Quaternary Conformation on the Biological Activities of the Asp49-phospholipases A(2)s from Snake Venoms

One of the main components of snake venoms are the Asp49-phospholipases A(2), also known as svPLA(2)s. The study of these toxins is a matter of great scientific interest due to their wide variety of biological effects. In this work we present strong evidences found in literature and other aspects which strengthen the importance of quaternary assembly for understanding the activities and molecular evolution of svPLA(2)s.

Biological behavior of the gerbil ventral prostate in three phases of postnatal development

In this study, we characterized the gerbil's ventral prostate histology ultrastructurally and quantitatively throughout three phases of postnatal development (young, adult, and old) in order to comprehend its biological behavior and propensity to developing spontaneous lesions with aging. The gerbil prostate is composed of alveoli and ducts immersed in a stroma composed of smooth muscle, fibroblasts, collagen and elastic fibers and vessels. The prostate tissue components present morphological and quantitative aspects that vary according to age. Young animals have an immature gland with modest secretory activity. Synthetic activity remained stable in adult and old gerbil. However, prostatic morphology was altered in the aging, showing an increased epithelium and stromal fibrosis. The nuclei of the secretory cells increased with aging, whereas nucleoli presented few alterations during postnatal development. The epithelial proliferation and stromal remodeling noted in this study indicate that the gerbil prostate may respond to the androgen declines typical of senescence through epithelial proliferation and stromal remodeling.

Photo-Fenton process for treating biological laboratory wastewater containing formaldehyde

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Biological leaching of Mn, Al, Zn, Cu and Ti in an anaerobic sewage sludge effectuated by Thiobacillus ferrooxidans and its effect on metal partitioning

The chemical fractionation and bioleaching of Mn, At, Zn, Cu and Ti in municipal sewage sludge were investigated using Thiobacillus ferrooxidans as leaching microorganism. As a result of the bacterial activity, ORP increase and pH reduction were observed. Metal solubilization was accomplished only in experimental systems supplemented with energy source (Fe(II)). The solubilization efficiency approached similar to80% for Mn and Zn, 24% for Cu, 10% for At and 0.2% for Ti. The chemical fractionation of Mn, At, Zn, Cu and Ti was investigated using a five-step sequential extraction procedure employing KNO3. KF, Na4P2O7, EDTA and HNO3. The results show that the bioleaching process affected the partitioning of Mn and Zn, increasing its percentage of elution in the KNO3 fraction while reducing it in the KF, Na4P2O7 and EDTA fractions. No significant effect was detected on the partitioning of Cu and Al. However, quantitatively the metals Mn, Zn, Cu and At were extracted with higher efficiency after the bacterial activity. Titanium was unaffected by the bioleaching process in both qualitative and quantitative aspects. (C) 2002 Elsevier B.V. Ltd. All rights reserved.

Quantitative aspects of the migration and evolutive asynchronism of Schistosoma mansoni in mice

Two groups of white mice (Mus musculus) were infected with 65 and 440 cercariae transcutaneously. Migration of Schistosoma mansoni from skin to the lungs and to the portal system thereafter was studied through fitting mathematical equations. Six evolutive stages previously defined were used to determine the asynchronic development of parasites in the portal system. Equations the moment of maximum schistosomula recovery in skin and lungs. In the portal system the equations lead to different days of maximum recovery according to each stage. These differences measure quantitatively the asynchronism of S. mansoni.

Adenocarcinoma in females detected in serous effusions: Cytomorphologic aspects and immunocytochemical reactivity to cytokeratins 7 and 20

OBJECTIVE: To investigate the usefulness of assessing the immunoreactivity of cytokeratins 7 (CK7) and 20 (CK20) as well as several cytomorphologic parameters in effusions with metastatic adenocarcinomas in the search for the primary site of the tumor. STUDY DESIGN: From the files of the Pathology Department, A. C. Camargo Hospital, we studied cytologic smears from 73 metastatic adenocarcinomas originally from the breast, 63 from the ovary, 40 from the lung and 32 from the stomach, looking for morphologic parameters that could have discriminant potential in suggesting the primary site in a routine situation, including intranuclear inclusions, prominent nucleoli, mitosis, signet-ring cells, psammoma bodies, nuclear crease, binucleation and multinucleation, papillary features, acinar profile (including ball cells) and single cells. Immunoreactions were performed with monoclonal antibodies to CK7 (OV-TL 12/30 and CK20 (Ks 20.8) and included morphologic analysis. Both analyses were studied in a blind fashion regarding the primary site of the tumors. RESULTS: Positivity ratios for breast, ovary, stomach and lung cases were 67.6%, 63.5%, 29.7% and 45.5%, respectively, for CK7 and 17.2%, 15.8%, 13.5% and 32.2%, respectively, for CK20. Discriminant analysis of morphologic and immunocytochemical parameters had an error rate of 42.9% in recognizing the primary site and a Wilk's lambda of .7290. CONCLUSION: The more efficient parameter with discriminant function was the papillary appearance showed by CK7, which should be used in further studies with a similar scope. The set of parameters used in this study were insufficient to discriminate the primary site of female adenocarcinomas in effusions with significant accuracy.

Hodgkin disease in adult and juvenile groups from two different geographic regions in Brazil: Characterization of clinicopathologic aspects and relationship with Epstein-Barr virus infection

We analyzed clinicopathologic data, immunophenotype, and Epstein-Barr virus (EBV) status in 96 cases of Hodgkin disease (HD) in juveniles (younger than 20 years) and adults (20 years or older) from 2 distinctive states in Brazil. We studied 34 juvenile (group 1) and 16 adult (group 2) cases from Ceara and 31 juvenile (group 3) and 15 adult (group 4) cases from São Paulo. Ceara has a socioeconomic profile similar to a developing country; São Paulo is in better economic condition. Mixed cellularity (MC) was the major histologic subtype among groups 1 (22 [65%]), 3 (21 [68%]), and 4 (7 [47%]); nodular sclerosis (NS) was more frequent in group 2 (8 [50%]). EBV infection was observed in 61 cases (64%), including the following (among others): group 1, MC, 22 (65%) and NS, 4 (12%); group 2, NS, 3 (19%) and MC, 2 (12%); group 3, MC, 16 (52%) and NS, 1 (3%); and group 4, MC, 7 (47%). There was predominance of EBV+ HD cases in group 1 compared with group 3. HD in Brazilian patients is highly associated with EBV infection, but geographic differences reflect histologic subtypes and age distribution.

Ultrastructural and Cytochemical Aspects of Metamorphosis in the Midgut of Apis mellifera L. (Hymenoptera: Apidae: Apinae)

The midgut of Apis mellifera is remodeled during metamorphosis. The epithelium and, to a lesser extent, the muscular sheath degenerate between the end of the last larval instar and the onset of pupation (prepupa).The larval epithelium is shed to the midgut lumen and digested, while a new epithelium is reconstructed from larval regenerative cells. During pupation, some reorganization still occurs, mainly in brown-eyed pupae. In pharate adult, the midgut wall shows the characteristics of adult, although some cells have pycnotic nuclei. The localization of alkaline and acid phosphatases showed that these enzymes were not involved in the reabsorption of the midgut wall.

The role of the oblique ligament in the mechanical behavior of the medial collateral ligament of the mongrel dog elbow joint - Some biomechanical aspects

This study investigated the oblique ligament mechanical contribution to the medial collateral ligament of the canine elbow joint. Fifteen dogs were used for the study of the failure load, displacement, and energy absorption of the medial collateral and oblique ligaments of the canine elbow joint, associate and separately in the joint. Medial collateral ligament failure load and energy absorption were significantly higher in relation to the isolated oblique ligament. When the ligaments were associated in the joint, they presented an increment in failure load, displacement and energy absorption in relation to the ligaments analyzed separately. It was concluded, therefore, that the oblique ligament could have an important paper in the stability of the canine elbow joint, as it favors the medial collateral ligament resistance to the tensile load, one of the main stabilizer of the elbow joint.

Some aspects of chicken behavior and welfare

Brazil is the world leader in broiler production and export. It achieved this position mainly to its excellent supply chain structure and climate, which favor poultry and grain production throughout its territory. Although Brazilian egg production is not as important as broiler production, this segment presents great potential of increasing its share in the global market. However, as elsewhere in the world, Brazilian poultry production faces the challenge to balance two elements within its supply chain: cruelty and productivity. The consumers of the European Union (EU) are very concerned with animal welfare issues. In order to increase its share in the European market, and eventually in the world market, Brazilian poultry producers must understand the effects of production systems on poultry welfare, and try to develop systems that are suited for its climate and other production conditions. There is a consensus that the natural behaviors performed by poultry in intensive production systems allow better welfare. This objective of this review is to present scientific research studies that relate different behaviors to chicken welfare. Poultry behavior is a reflex of their welfare status at a particular moment, and it is related to internal (physiological) and external (environmental) factors. Several natural behaviors that favor welfare, as well as undesirable behaviors, may be stimulated by environmental enrichment. The correct interpretation of the behaviors expressed by poultry, including their frequency, duration, and sequence, may be used to estimate their welfare. Animal production is an import sector of Brazilian economy. It significantly contributes to the Gross Domestic Product (GDP), in terms of products destined both to domestic consumption and exports. New technologies applied to products and management practices have been developed for field application, aiming at improving producers' productivity and profitability. In order to comply with the European Union's (EU) guidelines for animal protein production, Brazilian poultry production needs to undergo a process of adaptation. In May, 2007, the EU Commission established its new guidelines for animal welfare in poultry production, pressured by consumer demand. In the EU, there is a growing concern among consumers as to how poultry are reared and slaughtered. European consumers are in the fore front of the demand of high quality products produced with under better welfare conditions, and have spread this concern throughout the world. Beaumont et al. (2010) mentioned that European consumers frequently perceive that standard commercial poultry production has poor animal welfare practices. According to Nääs et al. (2008), Brazilian poultry production today needs to find a balance between cruelty and productivity. In fact, ensuring animal welfare may provide better financial results, as it increases the producer's profit margins and allows maintaining Brazilian chicken export quotas to the EU. França (2008) noted that biological studies that define ethical limits and guidelines for poultry production foster the development of new production practices that may ensure good product quality and productivity without putting bird welfare at risk. Gonyou (1994) states that, when animal welfare started to be studied, the only behavioral factors considered were those related to feeding and reproduction. These first studies used as indicators of animal welfare reduced life expectancy, impaired growth, impaired reproduction, body damage, disease, immunosuppression, adrenal activity, behavior anomalies, and self-narcotization (Broom, 1991). However, current studies evaluate additional indicators, such as natural behaviors, behavioral needs, preferences, behavioral problems, emotional state, cognitive abilities, etc. In the field of ethology, the expression of natural behavior is a frequently used tool used to estimate the welfare of poultry destined to human consumption. According to Bracke & Hopster (2006), natural behavior can be defined as the behavior the animal normaly presents when exposed to conditions similar to its natural habitat. Natural behaviors are pleasurable and promote biological functions that are meaningful to the animal's welfare. The definition of natural behavior, though, does not include the bird's behavior when sick, in flight or during aggression, since these are not considered pleasurable situations. Considering layer behavioral needs in the design of housing facilities optimize their welfare. Mishra et al. (2005) verified that ISA Brown layers spent, during 24 hours, around 97% of the time in the nest, feeding, walking, resting, or dust bathing, and that 57% of these behaviors did not depend on environmental enrichment. It was also observed that hens had preferred behavioral sequences, which included foraging and comfort behaviors, such as wing-stretching and preening. The present review aims at discussing, albeit not exhaustively, scientific research studies on the behavior of Gallusgallus domesticus and its relationship to welfare. The following behaviors are reviewed: feather pecking, scratching, dust bathing, nesting, locomotion activities, and aggressive behaviors. These behaviors are the most frequently observed in commercial broiler, broiler breeder, and layer farming, and therefore, monitoring their incidence may contribute to measure poultry welfare.

Semi-synthetic minimal cells: Biochemical, physical, and technological aspects

The construction of synthetic cells is one of the major goals of bioengineering. The most successful approach consists in the encapsulation of biochemical materials (DNA, RNA, enzymes, etc.) inside lipid vesicles (liposomes), mimicking a cell structure. In this contribution, that also aims at introducing the reader to 'chemical synthetic biology,' we describe the current state of the art of 'semi-synthetic minimal cells' (SSMCs), namely, cell-like structures containing the minimal number of biological compounds that are required to reconstruct a function of interest. We will first describe how the concept of the minimal cell was originated and its relation with the theory of autopoiesis, then we review the most advanced results focused on genetic/metabolic networks inside liposomes. Next, we emphasize that relevance of physical aspects (too often neglected) that impact on the solute entrapment process, and finally we discuss new technological trends in SSMC research that will probably allow their future use in biotechnology. © 2013 Copyright © 2013 Elsevier Inc. All rights reserved.

Leprosy: review of the epidemiological, clinical, and etiopathogenic aspects - Part 1

Leprosy is caused by Mycobacterium leprae and has been known since biblical times. It is still endemic in many regions of the world and a public health problem in Brazil. The prevalence rate in 2011 reached 1.54 cases per 10,000 inhabitants in Brazil. The mechanism of transmission of leprosy consists of prolonged close contact between susceptible and genetically predisposed individuals and untreated multibacillary patients. Transmission occurs through inhalation of bacilli present in upper airway secretion. The nasal mucosa is the main entry or exit route of M. leprae. The deeper understanding of the structural and biological characteristics of M. leprae, the sequencing of its genome, along with the advances in understanding the mechanisms of host immune response against the bacilli, dependent on genetic susceptibility, have contributed to the understanding of the pathogenesis, variations in the clinical characteristics, and progression of the disease. This article aims to update dermatologist on epidemiological, clinical, and etiopathogenic leprosy aspects.

Biomaterials from blends of fluoropolymers and corn starch-implant and structural aspects

The development of polymeric blends to be used as matrices for bone regeneration is a hot topic nowadays. In this article we report on the blends composed by corn starch and poly(vinylidene fluoride), PVDF, or poly(vinylidene fluoride-trifluoroethylene), P(VDF-TrFE), to obtain biocompatible materials. Blends were produced by compressing/annealing and chemically/structurally characterized by micro-Raman scattering and Fourier transform infrared (FTIR) absorption spectroscopies, dynamic mechanical analysis (DMA) and scanning electron microscopy (SEM), besides in vivo study to evaluate the tissue response. Vibrational spectroscopy reveals no chemical interaction between the polymers and starch, absence of material degradation due to compressing/annealing process or organism implantation, and maintenance of a and ferroelectric crystalline phases of PVDF and P(VDF-TrFE), respectively. As a consequence of absence of interaction between polymers and starch, it was possible to identify by SEM each material, with starch acting as filler. Elastic modulus (E') obtained from DMA measurement, independent of the material proportion used in blends, reaches values close to those of cancellous bone. Finally, the in vivo study in animals shows that the blends, regardless of the composition, were tolerated by cancellous bone. (C) 2013 Elsevier B.V. All rights reserved.