Pathophysiology and molecular aspects of diffuse large B-cell lymphoma

Diffuse large B-Cell lymphoma is the most common subtype of non-Hodgkin lymphoma in the West. In Brazil, it is the fifth cause of cancer, with more than 55,000 cases and 26,000 deaths per year. At Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo - HCFMUSP, diffuse large B-Cell lymphoma represents 49.7% of all non-Hodgkin lymphoma cases. Initially, the classification of non-Hodgkin lymphoma was based on morphology, but advances in immunology and molecular medicine allowed the introduction of a biological classification for these diseases. As for other cancers, non-Hodgkin lymphoma involves patterns of multi factorial pathogenesis with environmental factors, as well as genetic, occupational and dietary factors, contributing to its development. Multiple lesions involving molecular pathways of B-cell proliferation and differentiation may result in the activation of oncogenes such as the BCL2, BCL6,and MYC genes and the inactivation of tumor suppressor genes such as p53 and INK4, as well as other important transcription factors such as OCT-1 and OCT-2. A dramatic improvement in survival was seen after the recent introduction of the anti-CD20 monoclonal antibody. The association of this antibody to the cyclophosphamide, hydroxydaunorubicin, oncovin and prednisolone (CHOP) regimen has increased overall survival of diffuse large B-Cell lymphoma and follicular lymphoma patients by 20%. However, 50% of all diffuse large B-Cell lymphoma patients remain incurable, creating a demand for more research with new advances in treatment. Thus, it is important to know and understand the key factors and molecular pathways involved in the pathogenesis of diffuse large B-Cell lymphoma.

Virulence and molecular aspects of Bordetella avium isolated from cockatiel chicks (Nymphicus hollandicus) in Brazil

Bordetella avium is an opportunistic pathogen that presents tropism for ciliated epithelia, leading to upper respiratory tract disease in turkeys. This agent has also been associated with Lockjaw Syndrome in psittacine birds, but literatures describing the importance of this agent in such species are rare. The purpose of the present study was to report the first outbreak of B. avium infection in juvenile cockatiels demonstrating the Lockjaw Syndrome in Brazil and to investigate the antimicrobial resistance profile and phenotypic and genotypic characteristics of these strains. Surprising, the strains obtained from five infected cockatiel chicks from three different breeders from different Brazilian states showed a clonal relationship using the Pulsed Field Gel Electrophoresis and Single Enzyme Amplified Fragment Length Polymorphism techniques. The virulence potentials of the B. avium strains were assessed using tracheal adherence and cytotoxic effects on a VERO cell monolayer. (C) 2012 Elsevier B.V. All rights reserved.

Epidemiological, parasitological and molecular aspects of Giardia duodenalis infection in children attending public daycare centers in southeastern Brazil

The purpose of this study was to determine the prevalence, associated risk factors and genotype of Giardia duodenalis infection in children attending public daycare centers in the city of Araguari, state of Minas Gerais, Brazil. Fecal samples were collected from 245 children aged 0-5 years, and questionnaires were asked about sociodemographic and hygiene-related characteristics. At the daycare centers where children tested positive, fecal samples were collected from the staff handling food, and from family members and domestic animals. Positive samples were analyzed at the dehydrogenase glutamate (gdh) locus to determine the genotype. The prevalence of G. duodenalis was 51.8%, and drinking unfiltered and unboiled water (OR 2.12, CI 1.26-3.69, p<0.001) and washing hands only with water (OR 2.14, Cl 1.19-4.04, p<0.001) were related risk factors. No association was found between test-positive children anti their family members, domestic animals and food handlers. An analysis of the sequences of 30 samples revealed that they all belonged to genotype B. (C) 2012 Royal Society of Tropical Medicine and Hygiene. Published by Elsevier Ltd. All rights reserved.

Cloning and expression of embryogenesis-regulating genes in Araucaria angustifolia (Bert.) O. Kuntze (Brazilian Pine)

Angiosperm and gymnosperm plants evolved from a common ancestor about 300 million years ago. Apart from morphological and structural differences in embryogenesis and seed origin, a set of embryogenesis-regulating genes and the molecular mechanisms involved in embryo development seem to have been conserved alike in both taxa. Few studies have covered molecular aspects of embryogenesis in the Brazilian pine, the only economically important native conifer in Brazil. Thus eight embryogenesis-regulating genes, viz.,ARGONAUTE 1, CUP-SHAPED COTYLEDON 1, WUSCHEL-related WOX, S-LOCUS LECTIN PROTEIN KINASE, SCARECROW-like, VICILIN 7S, LEAFY COTYLEDON 1, and REVERSIBLE GLYCOSYLATED POLYPEPTIDE 1, were analyzed through semi-quantitative RT-PCR during embryo development and germination. All the eight were found to be differentially expressed in the various developmental stages of zygotic embryos, seeds and seedling tissues. To our knowledge, this is the first report on embryogenesis-regulating gene expression in members of the Araucariaceae family, as well as in plants with recalcitrant seeds.

Febrile response induced by cecal ligation and puncture (CLP) in rats: involvement of prostaglandin E-2 and cytokines

The purpose of the present study was to better understand the events involved in the febrile response induced by cecal ligation and puncture (CLP), a complex infectious process. To this end, we conducted in vivo experiments in rats examining (1) fever development, (2) bacterial number in the infection focus and in blood, (3) peripheral and hypothalamic synthesis of cytokines, (4) hypothalamic and cerebrospinal fluid (CSF) synthesis of prostaglandin E-2 (PGE(2)), (5) the effect of anti-IL-6 antibody on fever, and (6) the effect of celecoxib on fever and hypothalamic synthesis of PGE(2) after CLP induction. We found that CLP promotes fever and animal death depending on the number of punctures. The peak of CLP-induced fever overlapped with the maximal increase in the number of bacteria in the infectious focus and blood, which occurred at 6 and 12 h. The peak of the febrile response also coincided with increased amounts of interleukin (IL)-1 beta, IL-6 and IL-10 in the peritoneal exudate and serum; IL-6 in the hypothalamus and PGE(2) in the CSF and predominantly in the hypothalamus. Moreover, intracerebroventricularly injected anti-IL-6 antibody reduced the febrile response while celecoxib reduced the fever and PGE(2) amount in the hypothalamus induced by CLP. Tumor necrosis factor (TNF)-alpha peaked at 3 h at all sites studied. Conversely, IL-10 concentration decreased in the hypothalamus. These findings show that the peak of CLP-induced fever is accompanied by an increase of bacteria in peritoneal fluid (local infection) and blood; local synthesis of pyrogenic (IL-1 beta, IL-6) and antipyretic (IL-10) cytokines and central production of IL-6 and PGE(2), suggesting that these last are the central mediators of this response.

Clinical implication of 14-3-3 epsilon expression in gastric cancer

AIM: To evaluate for the first time the protein and mRNA expression of 14-3-3 epsilon in gastric carcinogenesis. METHODS: 14-3-3 epsilon protein expression was determined by western blotting, and mRNA expression was examined by real-time quantitative RT-PCR in gastric tumors and their matched non-neoplastic gastric tissue samples. RESULTS: Authors observed a significant reduction of 14-3-3 epsilon protein expression in gastric cancer (GC) samples compared to their matched non-neoplastic tissue, Reduced levels of 14-3-3 epsilon were also associated with diffuse-type GC and early-onset of this pathology. Our data suggest that reduced 14-3-3 epsilon may have a role in gastric carcinogenesis process. CONCLUSION: Our results reveal that the reduced 14-3-3 epsilon expression in GC and investigation of 14-3-3 epsilon interaction partners may help to elucidate the carcinogenesis process. (C) 2012 Baishideng. All rights reserved.

Different approaches, one target: understanding cellular mechanisms of Parkinson's and Alzheimer's diseases

Neurodegenerative disorders are undoubtedly an increasing problem in the health sciences, given the increase of life expectancy and occasional vicious life style. Despite the fact that the mechanisms of such diseases are far from being completely understood, a large number of studies; that derive from both the basic science and clinical approaches have contributed substantial data in that direction. In this review, it is discussed several frontiers of basic research on Parkinson's and Alzheimer's diseases, in which research groups from three departments of the Institute of Biomedical Sciences of the University of Sao Paulo have been involved in a multidisciplinary effort. The main focus of the review involves the animal models that have been developed to study cellular and molecular aspects of those neurodegenerative diseases, including oxidative stress, insulin signaling and proteomic analyses, among others. We anticipate that this review will help the group determine future directions of joint research in the field and, more importantly, set the level of cooperation we plan to develop in collaboration with colleagues of the Nucleus for Applied Neuroscience Research that are mostly involved with clinical research in the same field.

Expression of BAG-1 and PARP-1 in Precursor Lesions and Invasive Cervical Cancer Associated with Human Papillomavirus (HPV)

Cervical cancer remains persistently the second most common malignancies among women worldwide, responsible for 500,000 new cases annually. Only in Brazil, the estimate is for 18,430 new cases in 2011. Several types of molecular markers have been studied in carcinogenesis including proteins associated with apoptosis such as BAG-1 and PARP-1. This study aims to demonstrate the expression of BAG-1 and PARP-1 in patients with low-grade squamous intraepithelial lesions (LSILs), high-grade squamous intraepithelial lesions (HSILs) and invasive squamous cell carcinomas (SCCs) of the uterine cervix and to verify a possible association with HPV infection. Fifty samples of LSILs, 50 samples of HSILs and 50 samples of invasive SCCs of the uterine cervix were analyzed by immunohistochemistry for BAG-1 and PARP-1 expression. PCR was performed to detect and type HPV DNA. BAG-1 expression levels were significantly different between LSILs and HSILs (p = 0,014) and between LSILs and SCCs (p = 0,014). In regards to PARP-1 expression, we found significant differences between the expression levels in HSILs and SCCs (p = 0,022). No association was found between BAG-1 expression and the presence of HPV. However, a significant association was found between PARP-1 expression and HPV positivity in the HSILs group (p = 0,021). In conclusion our research suggests that BAG-1 expression could contribute to the differentiation between LSIL and HSIL/SCC whereas PARP-1 could be useful to the differentiation between HSIL HPV-related and SCC. Further studies are needed to clarify the molecular aspects of the relationship between PARP-1 expression and HPV infection, with potential applications for cervical cancer prediction.

Genes involved in thoracic exoskeleton formation during the pupal-to-adult molt in a social insect model, Apis mellifera

Background: The insect exoskeleton provides shape, waterproofing, and locomotion via attached somatic muscles. The exoskeleton is renewed during molting, a process regulated by ecdysteroid hormones. The holometabolous pupa transforms into an adult during the imaginal molt, when the epidermis synthe3sizes the definitive exoskeleton that then differentiates progressively. An important issue in insect development concerns how the exoskeletal regions are constructed to provide their morphological, physiological and mechanical functions. We used whole-genome oligonucleotide microarrays to screen for genes involved in exoskeletal formation in the honeybee thoracic dorsum. Our analysis included three sampling times during the pupal-to-adult molt, i.e., before, during and after the ecdysteroid-induced apolysis that triggers synthesis of the adult exoskeleton. Results: Gene ontology annotation based on orthologous relationships with Drosophila melanogaster genes placed the honeybee differentially expressed genes (DEGs) into distinct categories of Biological Process and Molecular Function, depending on developmental time, revealing the functional elements required for adult exoskeleton formation. Of the 1,253 unique DEGs, 547 were upregulated in the thoracic dorsum after apolysis, suggesting induction by the ecdysteroid pulse. The upregulated gene set included 20 of the 47 cuticular protein (CP) genes that were previously identified in the honeybee genome, and three novel putative CP genes that do not belong to a known CP family. In situ hybridization showed that two of the novel genes were abundantly expressed in the epidermis during adult exoskeleton formation, strongly implicating them as genuine CP genes. Conserved sequence motifs identified the CP genes as members of the CPR, Tweedle, Apidermin, CPF, CPLCP1 and Analogous-to-Peritrophins families. Furthermore, 28 of the 36 muscle-related DEGs were upregulated during the de novo formation of striated fibers attached to the exoskeleton. A search for cis-regulatory motifs in the 5′-untranslated region of the DEGs revealed potential binding sites for known transcription factors. Construction of a regulatory network showed that various upregulated CP- and muscle-related genes (15 and 21 genes, respectively) share common elements, suggesting co-regulation during thoracic exoskeleton formation. Conclusions: These findings help reveal molecular aspects of rigid thoracic exoskeleton formation during the ecdysteroid-coordinated pupal-to-adult molt in the honeybee.

Self-Assembly of Poly(4-vynil-N-alkylpyridinium) Bromide onto Silica: Effect of Side-Chain Length on Structural Aspects at a Molecular Level

Self-assembly of poly(4-vynil-N-alkyl)pyridinium bromide with alkyl side chains of 2, 5, 7, 10, or 16 carbons from ethanolic solutions onto flat silica surfaces was studied by means of ellipsometry, atomic force microscopy (AFM), contact angle measurements, and sum-frequency generation (SFG) vibrational spectroscopy in the CH3 and CH2 stretch region. Ab initio quantum-chemical calculations on the N-alkylpyridinium side-group with restricted Hartree-Fock (RHF) method and 6-311G (d,p) basis set were C one to estimate the charge distribution along the pyridinium ring and the alkyl side-chain. SFG results showed that longer side chains promote the disorientation of the alkyl groups at the surface, corroborating with the contact angle values. AFM images revealed film homogeneity, regardless the alkyl side group. However, after 24 h contact with water, ringlike structures appeared on the film surfaces, when the polycation alkyl side chain had 7 or less carbons, and as the alkyl chain increased to 10 or 16 carbons, the films dewetted because the hydrophobic interactions prevailed over the electrostatic interactions between the pyridinium charged groups and the negatively charged SiO2 surface. Under acid conditions (HCl 0.1 mol.L-1), the film mean thickness values decreased up to 50% of original values when the alkyl side chains were ethyl or pentyl groups due to ion-pair disruption, but for longer groups they remained unchanged. Quantum-chemical optimization and Mulliken electron population showed that (i) from C2 to C15 the positive charge at the headgroup (HG) decreased 0.025, while the charge at combined HG + alpha-CH2 increased 0.037; and (ii) for C6 or longer, the alkyl side group presents a tilt in the geometry, moving away from the plane. Such effects summed up over the whole polymer chain give support to suggest that when the side chains are longer than 7 carbons, the hydrophobic interaction decreases film stability and increases acid resistance.

Self-Organizing Maps of Molecular Descriptors for Sesquiterpene Lactones and Their Application to the Chemotaxonomy of the Asteraceae Family

The Asteraceae, one of the largest families among angiosperms, is chemically characterised by the production of sesquiterpene lactones (SLs). A total of 1,111 SLs, which were extracted from 658 species, 161 genera, 63 subtribes and 15 tribes of Asteraceae, were represented and registered in two dimensions in the SISTEMATX, an in-house software system, and were associated with their botanical sources. The respective 11 block of descriptors: Constitutional, Functional groups, BCUT, Atom-centred, 2D autocorrelations, Topological, Geometrical, RDF, 3D-MoRSE, GETAWAY and WHIM were used as input data to separate the botanical occurrences through self-organising maps. Maps that were generated with each descriptor divided the Asteraceae tribes, with total index values between 66.7% and 83.6%. The analysis of the results shows evident similarities among the Heliantheae, Helenieae and Eupatorieae tribes as well as between the Anthemideae and Inuleae tribes. Those observations are in agreement with systematic classifications that were proposed by Bremer, which use mainly morphological and molecular data, therefore chemical markers partially corroborate with these classifications. The results demonstrate that the atom-centred and RDF descriptors can be used as a tool for taxonomic classification in low hierarchical levels, such as tribes. Descriptors obtained through fragments or by the two-dimensional representation of the SL structures were sufficient to obtain significant results, and better results were not achieved by using descriptors derived from three-dimensional representations of SLs. Such models based on physico-chemical properties can project new design SLs, similar structures from literature or even unreported structures in two-dimensional chemical space. Therefore, the generated SOMs can predict the most probable tribe where a biologically active molecule can be found according Bremer classification.

Provisional Biopharmaceutical Classification of Some Common Herbs Used in Western Medicine

The aim of this study was to classify some markers of common herbs used in Western medicine according to the Biopharmaceutical Classification System (BCS). The BCS is a scientific approach to classify drug substances based upon their intestinal permeability and their solubility, at the highest single dose used, within the physiologically relevant pH ranges. Known marker components of twelve herbs were chosen from the USP Dietary Supplement Compendium Monographs. Different BCS parameters such as intestinal permeability (P-eff) and solubility (C-s) were predicted using the ADMET Predictor, which is a software program to estimate biopharmaceutical relevant molecular descriptors. The dose number (D-0) was calculated when information from the literature was available to identify an upper dose for individual markers. In these cases the herbs were classified according to the traditional BCS parameters using Peff and Do. When no upper dose could be determined, then the amount of a marker that is just soluble in 250 mL of water was calculated. This value, M-x, defines when a marker is changing from highly soluble to poorly soluble according to BCS criteria. This biopharmaceutically relevant value can be a useful tool for marker selection. The present study showed that a provisional BCS classification of herbs is possible but some special considerations need to be included into the classification strategy. The BCS classification can be used to choose appropriate quality control tests for products containing these markers. A provisional BCS classification of twelve common herbs and their 35 marker compounds is presented.

Effects of type I collagen coating on titanium osseointegration: histomorphometric, cellular and molecular analyses

The investigation of titanium (Ti) surface modifications aiming to increase implant osseointegration is one of the most active research areas in dental implantology. This study was carried out to evaluate the benefits of coating Ti with type I collagen on the osseointegration of dental implants. Acid etched Ti implants (AETi), either untreated or coated with type I collagen (ColTi), were placed in dog mandibles for three and eight weeks for histomorphometric, cellular and molecular evaluations of bone tissue response. While the histological aspects were essentially the same with both implants being surrounded by lamellar bone trabeculae, histomorphometric analysis showed more abundant bone formation in ColTi, mainly at three weeks. Cellular evaluation showed that cells harvested from bone fragments in close contact with ColTi display lower proliferative capacity and higher alkaline phosphatase activity, phenotypic features associated with more differentiated osteoblasts. Confirming these findings, molecular analyses showed that ColTi implants up-regulates the expression of a panel of genes well known as osteoblast markers. Our results present a set of evidences that coating AETi with collagen fastens the osseointegration by stimulating bone formation at the cellular and molecular levels, making this combination of morphological and biochemical modification a promising approach to treat Ti surfaces.

A New Subgeneric Classification of Rhipsalis (Cactoideae, Cactaceae)

Most Cactaceae have succulent stems and inhabit dry or arid areas, but some are epiphytes of humid regions. Rhipsalis is the largest genus of epiphytic cacti. Species of Rhipsalis are notoriously difficult to identify, and the subgeneric classification of the genus has remained controversial. Between 1837 and 1995, eight different subgeneric classifications have been proposed for Rhipsalis. The most comprehensive taxonomic treatment of the genus recognized five subgenera, Phyllarthrorhipsalis, Rhipsalis, Epallagogonium, Calamorhipsalis, and Erythrorhipsalis, characterized mainly by stem morphology. Here, molecular phylogenetic information combined with morphological data is used to re-evaluate the former subgeneric classifications proposed for the genus. Three monophyletic subgenera are recognized, Rhipsalis, Calamorhipsalis and Erythrorhipsalis, which are mainly characterized by floral traits. The changes proposed include expanding the circumscription of Rhipsalis by the inclusion of species previously included in Phyllarthrorhipsalis and Epallagogoniwn and recognizing a broader Calamorhipsalis, also including species from subgenus Epallagogonium. The circumscription of Erythrorhipsalis remains unchanged. For each subgenus a list of synonyms, a brief description and a list of species included are presented. A key for the identification of subgenera is also provided.