Diversity of Somatic Coliphages in Coastal Regions with Different Levels of Anthropogenic Activity in Sao Paulo State, Brazil

Bacteriophages are the most abundant and genetically diverse viruses on Earth, with complex ecology in both quantitative and qualitative terms. Somatic coliphages (SC) have been reported to be good indicators of fecal pollution in seawater. This study focused on determining the concentration of SC and their diversity by electron microscopy of seawater, plankton, and bivalve samples collected at three coastal regions in Sao Paulo, Brazil. The SC counts varied from < 1 to 3.4 x 103 PFU/100 ml in seawater (73 samples tested), from < 1 to 4.7 x 10(2) PFU/g in plankton (46 samples tested), and from < 1 to 2.2 x 10(1) PFU/g in bivalves (11 samples tested). In seawater samples, a relationship between the thermotolerant coliforms and Escherichia coli and SC was observed at the three regions (P = 0.0001) according to the anthropogenic activities present at each region. However, SC were found in plankton samples from three regions: Baixada Santista (17/20), Canal de Sao Sebastiao (6/14), and Ubatuba (3/12). In seawater samples collected from Baixada Santista, four morphotypes were observed: A1 (4.5%), B1 (50%), C1 (36.4%), and D1 (9.1%). One coliphage, Siphoviridae type T1, had the longest tail: between 939 and 995 nm. In plankton samples, Siphoviridae (65.8%), Podoviridae (15.8%), Microviridae (15.8%), and Myoviridae (2.6%) were found. In bivalves, only the morphotype B1 was observed. These SC were associated with enteric hosts: enterobacteria, E. coli, Proteus, Salmonella, and Yersinia. Baixada Santista is an area containing a high level of fecal pollution compared to those in the Canal de Sao Sebastiao and Ubatuba. This is the first report of coliphage diversity in seawater, plankton, and bivalve samples collected from Sao Paulo coastal regions. A better characterization of SC diversity in coastal environments will help with the management and evaluation of the microbiological risks for recreation, seafood cultivation, and consumption.

Low level laser therapy (LLLT) decreases pulmonary microvascular leakage, neutrophil influx and IL-1 beta levels in airway and lung from rat subjected to LPS-induced inflammation

Background and Objective. Low level laser therapy (LLLT) is a known anti-inflammatory therapy. Herein we studied the effect of LLLT on lung permeability and the IL-1 beta level in LPS-induced pulmonary inflammation. Study Design/Methodology. Rats were divided into 12 groups (n = 7 for each group). Lung permeability was measured by quantifying extravasated albumin concentration in lung homogenate, inflammatory cells influx was determined by myeloperoxidase activity, IL-1P in BAL was determined by ELISA and IL-1P mRNA expression in trachea was evaluated by RT-PCR. The rats were irradiated on the skin over the upper bronchus at the site of tracheotomy after LPS. Results. LLLT attenuated lung permeability. In addition, there was reduced neutrophil influx, myeloperoxidase activity and both IL-1 beta in BAL and IL-1 beta mRNA expression in trachea obtained from animals subjected to LPS-induced inflammation. Conclusion. LLLT reduced the lung permeability by a mechanism in which the IL-1 beta seems to have an important role.

Cholesterol Mediates Chitosan Activity on Phospholipid Monolayers and Langmuir-Blodgett Films

The polysaccharide chitosan has been largely used in many biological applications as a fat and cholesterol reducer, bactericide agent, and wound healing material. While the efficacy for some of such uses is proven, little is known about the molecular-level interactions involved in these applications. In this study, we employ mixed Langmuir and Langmuir-Blodgett (LB) films of negatively charged dimyristoyl phosphatidic acid (DMPA) anti cholesterol as cell membrane models to investigate the role of cholesterol in the molecular-level action of chitosan. Chitosan does not remove cholesterol froth the monolayer. The interaction with chitosan tends to expand the DMPA monolayer due to its interpenetration within the film. On the other hand, cholesterol induces condensation of the DMPA monolayer. The competing effects cause the surface pressure isotherms of mixed DMPA-cholesterol films on a chitosan subphase to be unaffected by the cholesterol mole fraction, due to distinct degrees of chitosan penetration into the film in the presence of cholesterol. By combining polarization-modulated infrared reflection absorption spectroscopy (PM-IRRAS) and sum-frequency generation spectroscopy (SFG), we showed that chitosan induces order into negatively charged phospholipid layers, whereas the opposite occurs for cholesterol. In conclusion, chitosan has its penetration in the film modulated by cholesterol, and electrostatic interactions with negatively charged phospholipids, such as DMPA, are crucial for the action of chitosan.

In vitro effect of low-level laser on odontoblast-like cells

The aim of this study was to evaluate the metabolism of odontoblast-like MDPC-23 cells subjected to direct LLL irradiation. The cells were seeded (20,000 cells/well) in 24-well plates and incubated for 24 hours at 37 degrees C. After this period, the culture medium (DMEM) was replaced by fresh DMEM supplemented with 2 or 5% (stress induction by nutritional deficit) or 10% fetal bovine serum (FBS). The cells were exposed to laser doses of 2, 4, 10, 15 and 25 J/cm(2) from a near infrared InGaAsP diode laser prototype (LASERTable; 780 +/- 3 nm, 40 mW). One control group (sham irradiation) was established for each experimental condition (laser dose x FBS supplementation). Three and 72 hours after the last irradiation, cells were analyzed with respect to metabolism, morphology, total protein expression and alkaline phosphatase (ALP) activity. Higher metabolism and total protein expression were observed 72 hours after the last irradiation at the doses of 15 and 25 J/cm(2) (Mann-Whitney; p<0.05). Higher ALP activity was obtained with 5% FBS when the cells were irradiated with doses of 2 and 10 J/cm(2). For the dose of 25 J/cm(2), the highest ALP activity was observed with 10% FBS. It was concluded that the LLLT parameters used in this study stimulated the metabolic activity of the MDPC-23 cells, especially at the doses of 15 and 25 J/cm(2).

Increased Viability of Odontoblast-Like Cells Subjected to Low-Level Laser Irradiation

Studies have shown that the increase of cell metabolism depends on the low level laser therapy (LLLT) parameters used to irradiate the cells. However, the optimal laser dose to up-regulate pulp cell activity remains unknown. Consequently, the aim of this study was to evaluate the metabolic response of odontoblast-like cells (MDPC-23) exposed to different LLLT doses. Cells at 20000 cells/cm(2) were seeded in 24-well plates using plain culture medium (DMEM) and were incubated in a humidified incubator with 5% CO(2) at 37 degrees C. After 24 h, the culture medium was replaced by fresh DMEM supplemented with 5% (stress by nutritional deficit) or 10% fetal bovine serum (FBS). The cells were exposed to different laser doses from a near infrared diode laser prototype designed to provide a uniform irradiation of the wells. The experimental groups were: G1: 1.5 J/cm(2) + 5% FBS; G2: 1.5 J/cm(2) + 10% FBS; G3: 5 J/cm(2) + 5% FBS; G4: 5 J/cm(2) + 10% FBS; G5: 19 J/cm(2) + 5% FBS; G6: 19 J/cm(2) + 10% FBS. LLLT was performed in 3 consecutive irradiation cycles with a 24-hour interval. Non-irradiated cells cultured in DMEM supplemented with either 5 or 10% FBS served as control groups. The analysis of the metabolic response was performed by the MTT assay 3 h after the last irradiation. G1 presented an increase in SDH enzyme activity and differed significantly (Mann-Whitney test, p < 0.05) from the other groups. Analysis by scanning electron microscopy showed normal cell morphology in all groups. Under the tested conditions, LLLT stimulated the metabolic activity of MDPC-23 cultured in DMEM supplemented with 5% FBS and exposed to a laser dose of 1.5 J/cm(2). These findings are relevant for further studies on the action of near infrared lasers on cells with odontoblast phenotype.

Improved voice activity detection algorithm using wavelet and support vector machine

This paper proposes an improved voice activity detection (VAD) algorithm using wavelet and support vector machine (SVM) for European Telecommunication Standards Institution (ETS1) adaptive multi-rate (AMR) narrow-band (NB) and wide-band (WB) speech codecs. First, based on the wavelet transform, the original IIR filter bank and pitch/tone detector are implemented, respectively, via the wavelet filter bank and the wavelet-based pitch/tone detection algorithm. The wavelet filter bank can divide input speech signal into several frequency bands so that the signal power level at each sub-band can be calculated. In addition, the background noise level can be estimated in each sub-band by using the wavelet de-noising method. The wavelet filter bank is also derived to detect correlated complex signals like music. Then the proposed algorithm can apply SVM to train an optimized non-linear VAD decision rule involving the sub-band power, noise level, pitch period, tone flag, and complex signals warning flag of input speech signals. By the use of the trained SVM, the proposed VAD algorithm can produce more accurate detection results. Various experimental results carried out from the Aurora speech database with different noise conditions show that the proposed algorithm gives considerable VAD performances superior to the AMR-NB VAD Options 1 and 2, and AMR-WB VAD. (C) 2009 Elsevier Ltd. All rights reserved.

Effect of low-level laser irradiation on odontoblast-like cells

Low-level laser therapy (LLLT), also referred to as therapeutic laser, has been recommended for a wide array of clinical procedures, among which the treatment of dentinal hypersensitivity. However, the mechanism that guides this process remains unknown. Therefore, the objective of this study was to evaluate in vitro the effects of LLL irradiation on cell metabolism (MTT assay), alkaline phosphatase (ALP) expression and total protein synthesis. The expression of genes that encode for collagen type-1 (Col-1) and fibronectin (FN) was analyzed by RT-PCR. For such purposes, oclontoblast-like cell line (MDPC-23) was previously cultured in Petri dishes (15000 cells/cm(2)) and submitted to stress conditions during 12 h. Thereafter, 6 applications with a monochromatic near infrared radiation (GaAlAs) set at predetermined parameters were performed at 12-h intervals. Non-irradiated cells served as a control group. Neither the MTT values nor the total protein levels of the irradiated group differed significantly from those of the control group (Mann-Whitney test; p > 0.05). On the other hand, the irradiated cells showed a decrease in ALP activity (Mann-Whitney test; p < 0.05). RT-PCR results demonstrated a trend to a specific reduction in gene expression after cell irradiation, though not significant statistically (Mann-Whitney test; p > 0.05). It may be concluded that, under the tested conditions, the LLLT parameters used in the present study did not influence cell metabolism, but reduced slightly the expression of some specific proteins.

Late Quaternary sedimentation in the Paraiba Basin, Northeastern Brazil: Landform, sea level and tectonics in Eastern South America passive margin

Late Quaternary deposits in the northeastern Brazil have been scarcely investigated, despite their relevance to the discussion of the post-rift evolution of the South American passive margin within the context of landform, sea level and tectonic deformation. Sedimentological, stratigraphic and morphological characterization of these deposits, referred as Post-Barreiras Sediments, led to their distinction from underlying Early/Middle Miocene strata. Based on optically stimulated luminescence (OSL) dating, two sedimentary units (PB1 and PB2) were recognized and related to the time intervals between 74.8 +/- 9.3 and 30.8 +/- 6.9 ka, and 8.8 +/- 0.9 and 1.8 +/- 0.2 ka, respectively. Unit PB1 consists of indurated sandstones and breccias either with massive bedding or complex types of soft sediment deformation structures generated by contemporaneous seismic activity. Unit PB2 is composed of massive sands or sands related to structures developed by dissipation of dunes. The present work, focusing on the Post-Barreiras Sediments, discusses landform, sea level and tectonics of the eastern South American passive margin during the latest Quaternary. Non-deposition and sub-aerial exposure related to the Tortonian worldwide low sea level combined with tectonic quiescence followed the Miocene transgression. Tectonic deformation in the latest Pleistocene created space to accommodate unit PB1 in downthrown faulted blocks and, perhaps, also synclines produced by strike-slip deformation. Although deposition of this unit was simultaneous with the progressive fall in sea level that followed the Last Interglacial Maximum, punctuated rises combined with land subsidence led to marine deposition close to the modern coastline. Renewed subsidence in the Holocene gave rise to accommodation of the Post-Barreiras Sediments. Most of unit PB2 was deposited during the Holocene Transgression, but it is not composed of marine sediments, which suggests either an insignificant rise in relative sea level or aeolian reworking of thin transgressive sands. The data presented here lead to a review of the evolution of the South American passive margin based on assumptions of uniform sedimentation and undeformed planation surfaces over a wide coastal area of the northeastern Brazil. (C) 2011 Elsevier B.V. All rights reserved.

In vitro Trypanocidal Activity of Phenolic Derivatives from Peperomia obtusifolia

The trypanocidal activity of crude extracts and fractions from the leaves and stems of Peperomia obtusifolia (Piperaceae) was evaluated in vitro against the epimastigote forms of Trypanosoma cruzi. Bioactivity-guided fractionation of the most active extracts afforded seven known compounds, including three chromanes, two furofuran lignans and two flavone C-diglycosides. The most active compounds were the chromanes peperobtusin A and 3,4-dihydro-5-hydroxy-2,7-dimethyl-8-(2 ``-methyl-2 ``-butenyl)-2-(4`-methyl-1`,3`-pentadienyl)-2H-1-benzopyran-6-carboxylic acid, with IC(50) values of 3.1 mu M (almost three times more active than the positive control benznidazole, IC(50) 10.4 mu M) and 27.0 mu M, respectively. Cytotoxicity assays using peritoneal murine macrophages indicated that the chromanes were not toxic at the level of the IC(50) for trypanocidal activity. This is the first report on the trypanocidal activity besides unspecific cytotoxicity of chromanes from Peperomia species. Additionally it represents the first time isolation of 3,4-dihydro5-hydroxy-2,7-dimethyl-8-(2 ``-methyl-2 ``-butenyl)-2-(4`-methyl-1`,3`-pentadienyl)-2H-1-benzopyran-6-carboxylic acid from P. obtusifolia.

A combined X-ray and theoretical study of flavonoid compounds with anti-inflammatory activity

The structure of 7,4`-dimethoxy-3`-acetylflavone (tithonin-Ac) has been determined by X-ray diffraction and its geometry is compared with optimized geometrical parameters obtained by means of density functional theory at the B3LYP/6-311++G(d,p) level of calculation. in addition, vertical ionization potential (IPv) and acidity for tithonin-Ac and two derivatives have been also calculated. Calculations of spin densities were also performed for the radical formed by the electron abstraction of other flavones. The unpaired electron is located on C3 carbon atom (21-25%). (C) 2008 Elsevier B.V. All rights reserved.

Crystal structure and theoretical calculations of Julocrotine, a natural product with antileishmanial activity

Julocrotine, N-(2,6-dioxo-l-phenethyl-piperidin-3-yl)-2-methyl-butyramide, is a potent antiproliferative agent against the promastigote and amastigote forms of Leishmania amazonensis (L.). In this work, the crystal structure of Julocrotine was solved by X-ray diffraction, and its geometrical parameters were compared with theoretical calculations at the B3LYP and HF level of theory. IR and NMR spectra also have been obtained and compared with theoretical calculations. IR absorptions calculated with the B3LYP level of theory employed together with the 6-311G+(d,p) basis set, are close to those observed experimentally. Theoretical NMR calculations show little deviation from experimental results. The results show that the theory is in accordance with the experimental data. (C) 2007 Wiley Periodicals, Inc.