Low level laser therapy accelerates the extracellular matrix reorganization of inflamed tendon

In tendon lesions, inflammation indicates the beginning of tissue repair and influences cell proliferation and the remodeling of the extracellular matrix (ECM). Low level laser (LLL) therapy has been an important method to induce tissue repair, and several studies have sought to better understand the therapeutic possibilities of this modality. This study analyzed the effect of LLL on the ECM of rat tendons during the early phase of the inflammatory process. Wistar rats received an intratendinous application of carrageenan adjacent to the osteotendinous region in the right paw. The animals were divided into the following groups: G1—intact, G2—animals with no treatment after the inflammation induction, G3—animals treated with LLL 1 and 3 h after induction of inflammation (4 J/cm² continuous). After 4 h of application, the animals of the two groups were euthanized with isoflurane overdose. Our results demonstrate that LLL therapy can promote decrease in non-collagenous protein and glycosaminoglycans content, as well as an increase in metalloproteinases ?9, which proved, for the first time, that LLL therapy promotes alterations in the inflamed tendons even when analyzed only four hours after this process occur and could be a useful tool to improve the balance in inflamed tissues.     

Gene and cell survival: lessons from prokaryotic plasmid R1

Plasmids are units of extrachromosomal genetic inheritance found in all kingdoms of life. They replicate autonomously and undergo stable propagation in their hosts. Despite their small size, plasmid replication and gene expression constitute a metabolic burden that compromises their stable maintenance in host cells. This pressure has driven the evolution of strategies to increase plasmid stability--a process accelerated by the ability of plasmids to transfer horizontally between cells and to exchange genetic material with their host and other resident episomal DNAs. These abilities drive the adaptability and diversity of plasmids and their host cells. Indeed, survival functions found in plasmids have chromosomal homologues that have an essential role in cellular responses to stress. An analysis of these functions in the prokaryotic plasmid R1, and of their intricate interrelationships, reveals remarkable overall similarities with other gene- and cell-survival strategies found within and beyond the prokaryotic world.     

Bioprospecting highly diverse endophytic Pestalotiopsis spp. with antibacterial properties from Maytenus ilicifolia, a medicinal plant from Brazil

Thirteen endophytic fungal strains of the genus Pestalotiopsis were isolated from the medicinal plant Maytenus ilicifolia Mart. ex. Reiss (commonly known as "espinheira santa") and their antimicrobial properties were investigated. Two isolates were successful in inhibiting the growth of the tested microorganisms (Escherichia coli, Klebsiella pneumoniae, Micrococcus luteus, Staphylococcus aureus, and methicillin-resistant Staphylococcus aureus (MRSA)) using the technique of bioautographic thin-layer chromatography (TLC) agar overlay assay. An analysis based on a polyphasic approach integrating taxonomic information, morphological traits, RAPD markers, and the sequencing of the ITS1-5.8S-ITS2 of the rDNA led to the assignment of the isolates as belonging to the species Pestalotiopsis microspora, Pestalotiopsis vismiae, and Pestalotiopsis leucothoes. Therefore, the present study presents a new approach to the study of endophytic fungi of the genus Pestalotiopsis.     

Olfactory contribution to Fos expression during mating in inexperienced male hamsters

Male hamsters are very dependent on chemosensory cues for normal mating behavior. We have previously reported that central, vomeronasal pathways are intensely and selectively activated during mating or pheromonal stimulation. The contribution of main olfactory sensory input to the patterns of c-fos activation was investigated in this study. Sexually inexperienced male hamsters were either made anosmic by intranasal infusion of zinc sulfate or remained intact. Fos protein immunoreactivity was analyzed in main olfactory and vomeronasal pathways of the zinc sulfate-treated, anosmic animals after mating with receptive females for 45 min, and compared with Fos patterns seen in intact mating animals, some of which have been described in a previous publication. The zinc sulfate-treated anosmic males described here all mated when given access to receptive females. Whether mated or unstimulated, anosmic males had little or no Fos expression in main olfactory pathways; significantly less even than in unstimulated intact animals. Mating did not increase Fos expression in main olfactory pathways of intact animals over that of unstimulated intact controls. However, Fos expression in central vomeronasal pathways was significantly higher in mating anosmic males, as in intact males, compared with appropriate non-mating controls. Fos expression was significantly different between intact and zinc sulfate-treated anosmic mating males in only one area studied. The rostral anterior medial amygdala, known to receive a small olfactory terminal field, had significantly lower Fos expression in zinc sulfate-treated anosmic males that mated when compared with intact-mating animals. Thus, functional main olfactory input to the rostral vomeronasal amygdala can be demonstrated but does not appear to be critical for mating behavior in previously inexperienced male hamsters with intact vomeronasal organs. Other main olfactory input appears to have a negligible contribution to Fos-patterns in such animals.      

The p85 regulatory subunit controls sequential activation of phosphoinositide 3-kinase by Tyr kinases and Ras

Class IA phosphoinositide 3-kinase (PI3K) is a heterodimer composed of a p85 regulatory and a p110 catalytic subunit that regulates a variety of cell responses, including cell division and survival. PI3K is activated following Tyr kinase stimulation and by Ras. We found that the C-terminal region of p85, including the C-Src homology 2 (C-SH2) domain and part of the inter-SH2 region, protects the p110 catalytic subunit from Ras-induced activation. Although the p110 activity associated with a C-terminal p85 deletion mutant increased significantly in the presence of an active form of Ras, purified wild type p85-p110 was only slightly stimulated by active Ras. Nonetheless, incubation of purified p85-p110 with Tyr-phosphorylated peptides, which mimic the activated platelet-derived growth factor receptor, restored Ras-induced p85-p110 activation. In conclusion, p85 inhibits p110 activation by Ras; this blockage is released by Tyr kinase stimulation, showing that the classical mechanism of class IA PI3K stimulation mediated by Tyr kinases also regulates Ras-induced PI3K activation.     

Bos indicus introgression into (peri‐)alpine cattle breeds – evidence from the analysis of bovine whey protein variants

The major bovine whey proteins, α‐lactalbumin (α‐LA) and β‐lactoglobulin (β‐LG), exhibit breed‐specific genetic variation. The aim of this study was to identify possible new protein variants and determine the distribution of variants across a variety of 18 taurine and indicine cattle breeds applying a DNA‐based sequencing approach. To this end, the open reading frames of the respective genes (LALBA and LGB) were sequenced in 476 animals. Within the LALBA gene, a previously unknown synonymous and a previously undesignated non‐synonymous nucleotide exchange were identified. Furthermore, two known α‐LA variants (A and B) and four known β‐LG variants (A, B, C and W) were determined. The occurrence of typical indicine variants in some taurine cattle breeds, such as Suisse Eringer, German Hinterwälder and Hungarian Grey Steppe, further supports the hypothesis of ancient Bos indicus introgression into (peri‐)alpine cattle breeds.     

Differential proteomic analysis of noncardia gastric cancer from individuals of northern Brazil

Gastric cancer is the second leading cause of cancer-related death worldwide. The identification of new cancer biomarkers is necessary to reduce the mortality rates through the development of new screening assays and early diagnosis, as well as new target therapies. In this study, we performed a proteomic analysis of noncardia gastric neoplasias of individuals from Northern Brazil. The proteins were analyzed by two-dimensional electrophoresis and mass spectrometry. For the identification of differentially expressed proteins, we used statistical tests with bootstrapping resampling to control the type I error in the multiple comparison analyses. We identified 111 proteins involved in gastric carcinogenesis. The computational analysis revealed several proteins involved in the energy production processes and reinforced the Warburg effect in gastric cancer. ENO1 and HSPB1 expression were further evaluated. ENO1 was selected due to its role in aerobic glycolysis that may contribute to the Warburg effect. Although we observed two up-regulated spots of ENO1 in the proteomic analysis, the mean expression of ENO1 was reduced in gastric tumors by western blot. However, mean ENO1 expression seems to increase in more invasive tumors. This lack of correlation between proteomic and western blot analyses may be due to the presence of other ENO1 spots that present a slightly reduced expression, but with a high impact in the mean protein expression. In neoplasias, HSPB1 is induced by cellular stress to protect cells against apoptosis. In the present study, HSPB1 presented an elevated protein and mRNA expression in a subset of gastric cancer samples. However, no association was observed between HSPB1 expression and clinicopathological characteristics. Here, we identified several possible biomarkers of gastric cancer in individuals from Northern Brazil. These biomarkers may be useful for the assessment of prognosis and stratification for therapy if validated in larger clinical study sets.     

Fungi isolated from insects in strawberry crops act as potential biological control agents of <Emphasis Type="Italic">Duponchelia fovealis</Emphasis> (Lepidoptera: Crambidae)

Entomopathogenic fungi were collected from insects, belonging to orders Lepidoptera, Coleoptera, Hemiptera, Hymenoptera, and Diptera, with signs of infection. Single-spore colonies were identified based on morphological traits and ribosomal ITS sequences. The most commonly found fungi were Fusarium oxysporum Schlechtendal and Beauveria bassiana (Balsamo-Crivelli) Vuillemin. Isolation of Trichoderma atroviride Bisset, Aspergillus flavipes (Bainier and Sartory) Thom and Church, Aspergillus iizukae Sugiyama, Penicillium mallochii Rivera, Urb and Seifert, Penicillium adametzioides S. Abe ex G. Smith, and Mucor nidicola Madden, Stchigel, Guarro and Starks associated to insects is reported for the first time. Tests with B. bassiana isolates against Duponchelia fovealis Zeller (Lepidoptera: Crambidae), showed high larval mortality in vitro and in greenhouse, demonstrating its potential as biological control agent. Understanding the fungal microbiota from insects can provide promising isolates for use in integrated pest management programs. This is the first report characterizing the mycobiota in insects collected in strawberry crops, and evaluating the pathogenicity of B. bassiana against D. fovealis, a pest that causes severe losses to farmers.     

Comparison of the genotoxic activities of the K-region dihydrodiol of benzo[a]pyrene with benzo[a]pyrene in mammalian cells: morphological cell transformation; DNA damage; and stable covalent DNA adducts

Benzo[a]pyrene (B[a]P) is the most thoroughly studied polycyclic aromatic hydrocarbon (PAH). Many mechanisms have been suggested to explain its carcinogenic activity, yet many questions still remain. K-region dihydrodiols of PAHs are metabolic intermediates depending on the specific cytochrome P450 and had been thought to be detoxification products. However, K-region dihydrodiols of several PAHs have recently been shown to morphologically transform mouse embryo C3H10T1/2CL8 cells (C3H10T1/2 cells). Because K-region dihydrodiols are not metabolically formed from PAHs by C3H10T1/2 cells, these cells provide a useful tool to independently study the mechanisms of action of PAHs and their K-region dihydrodiols. Here, we compare the morphological cell transforming, DNA damaging, and DNA adducting activities of the K-region dihydrodiol of B[a]P, trans-B[a]P-4,5-diol with B[a]P. Both trans-B[a]P-4,5-diol and B[a]P morphologically transformed C3H10T1/2 cells by producing both Types II and III transformed foci. The morphological cell transforming and cytotoxicity dose response curves for trans-B[a]P-4,5-diol and B[a]P were indistinguishable. Since morphological cell transformation is strongly associated with mutation and/or larger scale DNA damage in C3H10T1/2 cells, the identification of DNA damage induced in these cells by trans-B[a]P-4,5-diol was sought. Both trans-B[a]P-4,5-diol and B[a]P exhibited significant DNA damaging activity without significant concurrent cytotoxicity using the comet assay, but with different dose responses and comet tail distributions. DNA adduct patterns from C3H10T1/2 cells were examined after trans-B[a]P-4,5-diol or B[a]P treatment using 32P-postlabeling techniques and improved TLC elution systems designed to separate polar DNA adducts. While B[a]P treatment produced one major DNA adduct identified as anti-trans-B[a]P-7,8-diol-9,10-epoxide-deoxyguanosine, no stable covalent DNA adducts were detected in the DNA of trans-B[a]P-4,5-diol-treated cells. In summary, this study provides evidence for the DNA damaging and morphological cell transforming activities of the K-region dihydrodiol of B[a]P, in the absence of covalent stable DNA adducts. While trans-B[a]P-4,5-diol and B[a]P both induce morphological cell transformation, their activities as DNA damaging agents differ, both qualitatively and quantitatively. In concert with the morphological cell transformation activities of other K-region dihydrodiols of PAHs, these data suggest a new mechanism/pathway for the morphological cell transforming activities of B[a]P and its metabolites.     

Sustainable development

Perspectives on Global Change: The TARGETS Approach edited by Jan Rotmans and Bert de Vries Cambridge University Press, 1997. ￡40.00/$69.95 hbk (xv+463 pages) ISBN 0 521 62176 3.