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Objectives: Investigate whether and which synoviocytes would acquire trained immunity characteristics that could exacerbate joint inflammation following a secondary Staphylococcus aureus infection., Methods: Lipopolysaccharide (LPS) and S. aureus were separately or double injected (21 days of interval) into the tibiofemoral joint cavity of male C57BL/6 mice. At different time points after these stimulations, mechanical nociception was analyzed followed by the analysis of signs of inflammation and damage in the affected joints. The trained immunity markers, including the glycolytic and mTOR pathway, were analyzed in whole tissue or isolated synoviocytes. A group of mice was treated with Rapamycin, an mTOR inhibitor before LPS or S. aureus stimulation., Results: The double LPS - S. aureus hit promoted intense joint inflammation and damage compared to single joint stimulation, including markers in synoviocyte activation, production of proinflammatory cytokines, persistent nociception, and bone damage, despite not reducing the bacterial clearance. The double LPS - S. aureus hit joints increased the synovial macrophage population expressing CX3CR1 alongside triggering established epigenetic modifications associated with trained immunity events in these cells, such as the upregulation of the mTOR signaling pathway (p-mTOR and HIF1α) and the trimethylation of histone H3. Mice treated with Rapamycin presented reduced CX3CR1 + macrophage activation, joint inflammation, and bone damage., Conclusions: There is a trained immunity phenotype in CX3CR1 + synovial macrophages that contributes to the exacerbation of joint inflammation and damage during septic arthritis caused by S. aureus., (© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Objective: to assess the effectiveness of 5% Brazilian green propolis (ointment) in individuals with chronic ulcers., Methods: a randomized clinical trial, developed with 40 patients randomized equally to control group (treated with essential fatty acid) and experimental group (treated with 5% green propolis) for 30 days. The outcomes of interest were sociodemographic, clinical and laboratory characteristics, lesion characteristics, such as type of tissue in the bed, presence of exudate, edge characteristics, microbial content and pain., Results: regarding sociodemographic, clinical and laboratory characteristics, the two groups did not show statistically significant differences. After assessment in 30 days, an effect was observed for both treated groups, but for the experimental group, greater effectiveness in terms of the type of tissue in the bed, type of exudate, edge characteristics, microbial content and pain., Conclusion: propolis-based ointment showed a healing effect, presenting itself as a potential tool in healing chronic ulcers.

Introduction: Postural instability and gait impairments are common in people with PD, both of which have a negative effect on their quality of life. Systematic reviews have demonstrated benefits of using exergaming in enhancing these outcomes. However, there is no consensus over whether exergaming therapy is better than conventional physical therapy for enhancing gait, balance, and quality of life., Objectives: The aim of this overview is to systematically synthesize and evaluate the available evidence found in published systematic reviews and meta-analyses, on the effects of exergaming therapy on balance, gait, and quality of life, compared to conventional physical therapy or no intervention., Methods: This overview was reported in accordance with the statement of Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA). A comprehensive search was carried out in nine databases. Two reviewers independently extracted data using a standardized forms and the search strategy included terms related to intervention, population, and study type. The methodological quality of the included systematic reviews/meta-analysis (SRs/Mas) was evaluated using the "A Measurement Tool to Assess Systematic Reviews 2" (AMSTAR-2). The "Grading of Recommendations Assessment, Development and Evaluation" (GRADE) was used to assess the quality of the evidence. The risk of bias assessment was performed using the "Risk Of Bias In Systematic Reviews" (ROBIS). PROSPERO registration number: CRD42021238131., Results: 112 SRs/MAs were found and nine of them were selected. Six reviews were rated as very low methodological quality and three reviews as low methodological quality. Five reviews were classified with low risk of bias and four reviews with high risk of bias. Most of the SR/MAs demonstrated significant effects on balance favoring exergaming therapy over conventional therapy, however those studies had been rated as very low quality of evidence. Inconclusive results were found for the quality of life and gait outcomes., Conclusion: Exergaming therapy shows promise for the rehabilitation of PD. However, this overview was unable to conclude with certainty that exergaming therapy is superior to conventional physical therapy in improving gait, balance, or quality of life in people with PD. The effectiveness of exergaming therapy in the treatment of people with PD still need to be verified by high-quality studies., (© 2023 John Wiley & Sons Ltd.)

Background: Knowledge of facial anatomy is essential for professionals intending to inject hyaluronic acid (HA) into that region, but due to the considerable anatomical variations in region, it does not guarantee the complete safety of the procedure. Similarly, procedures widely disseminated among professionals, such as aspiration and the use of cannulas, do not ensure total safety against vascular occlusion events caused by the filler., Objectives: This article describes a technique for injecting hyaluronic acid into the face guided by Doppler ultrasonography (DUS) in order to ensure greater safety against vascular occlusion events secondary to the procedure., Methods: We describe a Doppler ultrasound-guided filling technique, with an 18 MHZ transducer, consisting of three steps: arterial mapping, real-time ultrasound-guided filling, and assessing the perfusion., Results: The described technique was performed in 480 patients and can be adopted in the routine of professionals who inject hyaluronic acid, especially in areas at high risk for vascular events. Its use results in greater safety against vascular occlusion events secondary to the procedure, without the need for prior aspiration. We conclude that there is a local vasodilation right after the filling that makes it difficult the possibility of extrinsic compression exerted by the filler on the vessel. Furthermore, the product moves to deep planes even with the bevel facing up (toward the epidermis)., Conclusions: We believe that in the future the use of Doppler ultrasound-guided filling technique will be mandatory for professionals who intend to perform HA injection, to both ensure patient safety and provide legal protection for the professional., (© 2021 Wiley Periodicals LLC.)

Fluoxetine (FLX) is among the top 100 pharmaceutical prescribed annually worldwide and consequently is often detected in wastewater treatment plant effluent and surface waters, in concentrations up to 2.7 and 0.33 μg/L, respectively. Despite the presence of FLX in surface waters, little is known about its chronic effects in fish. Thus, this study aimed at investigating the chronic toxicity of FLX to Danio rerio adults. Rate of weight gain, behavior (feeding and swimming activity) and tissue organization (liver and intestine) were evaluated, after 30 days exposure. A lower rate of weight gain was observed at 100 μg/L FLX. The food intake time decreased, showing a decrease in fish appetite. The preference for the upper aquarium layer was observed at 10 and 100 μg/L of FLX, indicating an inhibition of the stress level (anxiolytic effect). Mild to moderate damage of hepatic tissue and a decrease epithelium height and increase in villus height of intestine were observed in fish exposed to concentrations as low as 0.01 μg/L. Based on obtained results, chronic exposure of fish to FLX could affect swimming and feeding behavior and alter morphological structure of liver and intestine tissues at environmental levels., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Inc. All rights reserved.)

The use of natural antioxidants in cancer therapy has increased: first, due to the potential of natural antioxidants to kill tumour cells and second, because of their capacity to protect healthy cells from the damage caused by chemotherapy. This review article discusses the antioxidant properties of extracts obtained from medicinal plants from the Brazilian Cerrado and the cell death profile induced by each of these extracts in malignant cells. Next, we describe the capacity of other medicinal plants from the Cerrado to protect against chemotherapy-induced cell toxicity. Finally, we focus on recent insights into the cell death profile induced by extracts from Cerrado plants and perspectives for future therapeutic approaches., Competing Interests: The authors declare that they have no conflicts of interest.

This controlled randomized clinical trial evaluated the effect of associating at-home and in-office bleaching procedures on tooth sensitivity (TS) and bleaching effectiveness. Forty patients subjected to on session of in-office bleaching with 38% peroxide hydrogen. Subsequently, the patients were randomly allocated to receive a second session of in-office bleaching or to use a tray containing 10% carbamide peroxide delivered during 7 consecutive days. The worst TS score reported during or after each bleaching procedure was recorded using a verbal rating scale and TS risk (score different from 0) was calculated. Color changes were measured 7 days after each in-office session (for patients receiving in-office procedures only) or after the end of at-home bleaching (for the combined protocol), and 6 months after the last procedure for both bleaching protocols. Color was assessed by a spectrophotometer and by color match with the Vita Classical and Bleach guide scales. Statistical analyses were carried out to assess possible differences between the protocols regarding the outcomes and to analyze the effect of time of assessment on color changes. The bleaching protocol did not affect the risk for and the maximum level of TS reported, irrespective of the time of assessment. In the color evaluation, the bleaching protocol also did not affect the ultimate tooth color. In conclusion, after one in-office bleaching session, there was no difference in bleaching effectiveness and TS between performing a second in-office session and associating it with 1-week at-home bleaching.

Background: Gestational diabetes is a risk factor for future development of type 2 diabetes. The primary aim of this study was to estimate the prevalence of postpartum glucose tolerance status evaluation in pregnancies complicated by gestational diabetes 6-12 weeks after delivery. The secondary one was to identify the factors that are implicated with postpartum glucose retesting., Methods: This was a retrospective study performed with a cohort of women with gestational diabetes, with prenatal care and delivery at a tertiary care center, from January 2013 to April 2017. The diagnosis of gestational diabetes was based on IADPSG criteria (Fasting ≥ 92 mg/dl, 1 h ≥ 180 mg/dl and/or 2 h ≥ 153 mg/dl, respectively) and the diagnosis of type 2 diabetes and prediabetes were made using the 2016 ADA's criteria (fasting and 2 h after glucose load ≥ 126 mg/dl and/or ≥ 200 and 100-125 mg/dl and/or 140 and 199 mg/dl, respectively). All women had an appointment scheduled 6-12 weeks postpartum with the results of a 75-g oral glucose tolerance test (OGTT)., Results: Of the 152 evaluated women, 21 (13.8%) returned with the postpartum OGTT results. Of these, 9 (45.0%) had a diagnosis of prediabetes. The use of insulin during gestation was the only factor implicated in a higher adherence rate to postpartum testing OR 6.33 (p 0.002). No significance was found for other demographic and clinical variables (age, family income, years of study, parity, gestational age at first visit, smoking, family history of type 2 diabetes, diagnosis of gestational diabetes before the third trimester, pregestational body mass index, previous history of gestational diabetes and ethnicity)., Conclusion: The majority of patients with gestational diabetes did not return postpartum to perform OGTT and in our study the only factor implicated in a higher postpartum return was the use of insulin during pregnancy. Considering that 45.0% were diagnosed with prediabetes, diabetes care teams should initially identify non-adherent patients.

Ureaplasma diversum infection in bovine females may result in various reproductive problems, including granular vulvovaginitis, abortion, weak calves, salpingitis, and spontaneous abortion. The presence of U. diversum in a dairy bovine population from midwestern Brazil has not been established. The aim of this study was to determine whether U. diversum was present in dairy cattle from midwestern Brazil using polymerase chain reaction (PCR). Vulvovaginal mucus was analyzed from 203 cows located in six municipalities in the north region of Mato Grosso State, Brazil. A total of 25% of dairy cows with vulvovaginitis were positive for U. diversum. The factors evaluated were included in a multivariable logistic regression model with the presence of at least one positive cow in the herd serving as the dependent variable. Three variables were significantly associated with a U. diversum-positive PCR and were included in the final multivariable model: number of parities, vulvar lesions, and reproductive problems. For each new parity, the chance of U. diversum infection decreased 0.03-fold, indicating that cows with the highest number of parities were more protected. The presence of vulvar lesions was increased 17.6-fold in females positive for U. diversum, suggesting that this bacterium could be related to the red granular lesions in the vulvar mucosa, whereas reproductive problems were increased 7.6-fold. However, further investigations should be conducted to ascertain the effects of U. diversum in association with other mycoplasma species in the herds studied.

Background: During Trypanosoma cruzi infection, macrophages produce reactive oxygen species (ROS) in a process called respiratory burst. Several works have aimed to elucidate the role of ROS during T. cruzi infection and the results obtained are sometimes contradictory. T. cruzi has a highly efficiently regulated antioxidant machinery to deal with the oxidative burst, but the parasite macromolecules, particularly DNA, may still suffer oxidative damage. Guanine (G) is the most vulnerable base and its oxidation results in formation of 8-oxoG, a cellular marker of oxidative stress., Methodology/principal Findings: In order to investigate the contribution of ROS in T. cruzi survival and infection, we utilized mice deficient in the gp91phox (Phox KO) subunit of NADPH oxidase and parasites that overexpress the enzyme EcMutT (from Escherichia coli) or TcMTH (from T. cruzi), which is responsible for removing 8-oxo-dGTP from the nucleotide pool. The modified parasites presented enhanced replication inside murine inflammatory macrophages from C57BL/6 WT mice when compared with control parasites. Interestingly, when Phox KO macrophages were infected with these parasites, we observed a decreased number of all parasites when compared with macrophages from C57BL/6 WT. Scavengers for ROS also decreased parasite growth in WT macrophages. In addition, treatment of macrophages or parasites with hydrogen peroxide increased parasite replication in Phox KO mice and in vivo., Conclusions: Our results indicate a paradoxical role for ROS since modified parasites multiply better inside macrophages, but proliferation is significantly reduced when ROS is removed from the host cell. Our findings suggest that ROS can work like a signaling molecule, contributing to T. cruzi growth inside the cells.

Plasma membrane proteolipid 3 (PMP3) is a class of small hydrophobic proteins found in many organisms including higher plants. Some plant PMP3 genes have been shown to respond to abiotic stresses and to participate in the processes of plant stress tolerance. In this study, we isolated the cassava (Manihot esculenta Crantz) MePMP3-2 gene and functionally characterized its role in tolerance to abiotic stress by expressing it in rice (Oryza sativa L.). MePMP3-2 encodes a 77-amino acid protein belonging to a subgroup of plant PMP3s that have long hydrophylic C-terminal tails of unknown function. In silico analysis and co-localization studies indicated that MePMP3-2 is a plasma membrane protein with two transmembrane domains, similar to other PMP3s. In cassava leaves, MePMP3-2 expression was up-regulated by salt and drought stresses. Heterologous constitutive expression of MePMP3-2 in rice did not alter plant growth and development but increased tolerance to salt and drought stresses. In addition, under stress conditions MePMP3-2 transgenic plants accumulated less malondialdehyde, had increased levels of proline, and exhibited greater up-regulation of the stress-related genes OsProT and OsP5CS, but led to only minor changes in OsDREB2A and OsLEA3 expression. These findings indicate that MePMP3-2 may play an important role in salt and drought stress tolerance in transgenic rice.

Main Conclusion: RCI2 / PMP3 s participate in abiotic stress responses and impact the expression of other genes. Their multifunctionality is determined by differential expression and by distinct activities of their structurally different proteins. In plants, RCI2/PMP3 genes, which encode small membrane proteins of the PMP3 family, are closely associated with abiotic stress responses. Their involvement in mediating stress tolerance is supported by genetic evidence and overexpression studies. RCI2/PMP3s occur as multigenes in plant genomes and their encoded proteins belong to distinct and conserved structural groups. In addition, different isoforms appear to be targeted to the plasma membrane or to distinct endomembrane compartments in cells. Several studies have revealed that RCI2/PMP3 proteins participate in cell ion homeostasis, and in regulation of membrane stability and polarization. They also appear to potentiate plant transcriptional responses to abiotic stresses. However, their mechanisms of action remain unknown. This paper reviews the current knowledge of the multiple roles of plant RCI2/PMP3 genes resulting from their differential expression under normal and stress conditions. The structural diversity of RCI2/PMP3 proteins is analyzed and evidence supporting their functional specialization and possible activity mechanisms is examined. Finally, strategies are discussed for exploiting new and established technologies to overcome the difficulties posed by the multigene status of RCI2s and the integral membrane character of their proteins, enabling the probing of their individual functions and collective significance.

Background: The aim of this study was to identify predictors of 30-day mortality in patients with malignant pleural effusion (MPE) who need pleural palliative procedures., Methods: Data was prospectively collected from our database, between January 2013 and July 2014 on 86 patients with MPE and complete follow-up 30 days after the procedure. The sample was divided into two groups. The first group (G1) included patients who had died up to 30 days after the palliative procedure, and the second group (G2) included patients who survived for more than 30 days after the palliative procedure. The identification of prognostic factors occurred through univariate analysis using Fisher exact test for analysis of categorical variables and the t test for quantitative variables. Subsequently, all variables were used in the multivariate logistic regression analysis. The cutoff values for any significant continuous variables were determined by receiver operating characteristics analysis., Results: There were 24 patients in G1 and 62 patients in G2. Univariate analysis of factors affecting postprocedural survival disclosed nine factors that were associated with significantly reduced postoperative survival. At the multivariate analysis, high levels of white blood cells, (p = .013), low levels of red blood cells (p < .0001) and protein in pleural fluid (p = .001), and primary lung and gastrointestinal sites (p = .0076) were identified as independent predictors of mortality., Conclusions: We identified four factors that are easily recognized in daily practice and can help select patients with low life expectancy. Therefore, invasive procedures and hospitalizations for this subgroup of patients can be prevented.

The estuary of the River Elbe between Hamburg and the North Sea (Germany) is a sink for contaminated sediment and suspended particulate matter (SPM). One major concern is the effect of human activities on the hydrodynamics, particularly the intensive dredging activities in this area that may result in remobilization of sediment-bound pollutants. The aim of this study was to identify pollutants contributing to the toxicological risk associated with re-suspension of sediments in the Elbe Estuary by use of an effect-directed analysis that combines chemical and biological analyses in with specific fractionation techniques. Sediments were collected from sites along the Elbe Estuary and a site from a small harbor basin of the Elbe Estuary that is known to be polluted. The sixteen priority EPA-PAHs were quantified in organic extracts of sediments. In addition, dioxin equivalents of sediments were investigated by use of the 7-ethoxyresorufin O-deethylase assay with RTL-W1 cells and the Ah receptor-mediated luciferase transactivation assay with H4IIE-luc cells. Quantification of the 16 priority PAHs revealed that sediments were moderately contaminated at all of the sites in the Elbe River Estuary (<0.02-0.906 µg/g dw). Sediments contained relatively small concentrations of dioxin equivalents (Bio-TEQ) with concentrations ranging from 15.5 to 322 pg/g dw, which were significantly correlated with dioxin equivalents calculated based on toxicity reference values and concentrations of PAH. The concentration of Bio-TEQ at the reference site exceeded 200,000 pg/g dw. In a potency balance the 16 PAHs explained between 47 and 118% of the Bio-TEQ in the luciferase assay, which can be explained by the constant input of PAHs bound to SPM from the upper course of the Elbe River into its estuary. Successful identification of a significant portion of dioxin-like activity to priority PAHs in complex environmental samples such as sediments has rarely been reported.

An essential step in the biosynthesis of bioactive brassinosteroids (BRs) in plants is the hydroxylation at C-22, a reaction catalyzed by P450 enzymes of the CYP90B and CYP724B subfamilies. Genes for both types of enzymes are present in many species, and in rice (Oryza sativa) and tomato (Solanum lycopersicum) both CYP90B and CYP724B enzymes contribute to C-22 hydroxylation. In Arabidopsis (Arabidopsis thaliana), C-22 hydroxylation of BRs is catalyzed by CYP90B1 (encoded by DWF4) and null dwf4 mutants show severe symptoms of BR-deficiency. CYP724A1 (At5g14400), an Arabidopsis gene of unknown function and limited expression, encodes a P450 sharing less than 55% sequence identity to CYP724B proteins. We used transgenic plants of the null mutants dwf4-102 and a novel allele, bashful (bsf), ectopically expressing the CYP724A1 gene to investigate the potential activity of CYP724A1 as a C-22 hydroxylase of BRs. Defects associated with BR deficiency were reversed and a normal growth habit restored in transgenic dwf4-102 and bsf plants overexpressing CYP724A1. The vegetative phase was prolonged and the transgenic plants were on average larger than wild type plants with respect to several morphometric parameters. Fertility was restored in the transgenic plants but individual siliques yielded fewer and heavier seeds than those of wild type plants. The implications of these findings with regard to the functions of CYP724A1 and the activity of its encoded enzyme are discussed., (Copyright © 2011 Elsevier GmbH. All rights reserved.)

The Tietê River and its tributary Pinheiros River receive a highly complex organic and inorganic pollutants load from sanitary sewage and industrial sources, as well as agricultural and agroindustrial activities. The aim of the present study was to evaluate the embryotoxic and teratogenic effects of sediments from selected locations in the Tietê River Basin by means of the sediment contact embryo toxicity assay with Danio rerio, in order to provide a comprehensive and realistic insight into the bioavailable hazard potential of these sediment samples. Lethal and sub-lethal effects were recorded, and high embryo toxicity could be found in the samples not only in the vicinity of the megacity São Paulo (Billings reservoir and Pinheiros River samples), but also downstream (in the reservoirs Barra Bonita, Promissão and Três Irmãos). Results confirm that most toxicity is due to the discharges of the metropolitan area of São Paulo. However, they also indicate additional sources of pollutants along the river course, probably from industrial, agricultural and agroindustrial residues, which contribute to the degradation of each area. The sediment contact fish embryo test showed to be powerful tool to detect embryo toxicity in sediments, not only by being a sensitive method, but also for taking into account bioavailability. This test provides an ecological highly realistic and relevant exposure scenario, and should therefore be added in ecotoxicological sediment quality assessments., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Many abiotic stimuli, such as drought and salt stresses, elicit changes in intracellular calcium levels that serve to convey information and activate adaptive responses. Ca²⁺ signals are perceived by different Ca²⁺ sensors, and calmodulin (CaM) is one of the best-characterized Ca²⁺ sensors in eukaryotes. Calmodulin-like (CML) proteins also exist in plants, but their functions at the physiological and molecular levels are largely unknown. In this report, we present data on OsMSR2 (Oryza sativa L. Multi-Stress-Responsive gene 2), a novel calmodulin-like protein gene isolated from rice Pei'ai 64S (Oryza sativa L.). Expression of OsMSR2 was strongly up-regulated by a wide spectrum of stresses, including cold, drought, and heat in different tissues at different developmental stages of rice, as revealed by both microarray and quantitative real-time RT-PCR analyses. Analysis of the recombinant OsMSR2 protein demonstrated its potential ability to bind Ca²⁺ in vitro. Expression of OsMSR2 conferred enhanced tolerance to high salt and drought in Arabidopsis (Arabidopsis thaliana) accompanied by altered expression of stress/ABA-responsive genes. Transgenic plants also exhibited hypersensitivity to ABA during the seed germination and post-germination stages. The results suggest that expression of OsMSR2 modulated salt and drought tolerance in Arabidopsis through ABA-mediated pathways.

Genotoxicity can be correlated with adverse reproductive effects or may even result in elevated extinction risk for particular species of an ecosystem. It may thus be a valuable tool for screening of pollution and potential environmental harm. Since many genotoxicants tend to adsorb onto particulate matter, sediments and suspended materials are of particular interest for genotoxicity screening under field conditions. In order to correlate the genotoxic potential of sediments with genetic damage in fish, rainbow-trout liver (RTL-W1) cells were exposed in vitro to acetone extracts of sediments collected at 10 selected sites along the upper Danube River and analyzed in the comet and micronucleus assays. These in vitro results were compared with micronucleus formation in erythrocytes of the European barbel (Barbus barbus) caught in the field. The two in vitro bioassays showed excellent correlation, indicating comparability of genotoxic potentials in vitro. Sampling sites could be clearly differentiated with respect to severity of effects, with Rottenacker as the most heavily contaminated site, Ehingen and Schwarzach as moderately genotoxic, and with the weakest effects in the tributary Lauchert. All other sediment extracts showed intermediate genotoxic or clastogenic effects. In situ, micronucleus formation in barbel erythrocytes indicated severe genotoxicity at Rottenacker, moderate effects at Ehingen, but minor contamination at Riedlingen and Sigmaringen. In situ observations thus showed excellent correlation with corresponding in vitro tests and document the ecological relevance of in vitro studies with sediment extracts. With respect to the ecological status of the Danube River, the results overall indicate a moderate to severe genotoxic potential with a highly differential localization., (Copyright 2010 Elsevier B.V. All rights reserved.)

The in vitro comet assay with the permanent fish cell line RTL-W1 and the in situ micronucleus assay using erythrocytes from indigenous tilapia (Oreochromis niloticus) were used to detect genotoxicity in Tietê River sediments (São Paulo, Brazil). Either test was successful in identifying site-specific differences in genotoxicity, with a high correlation between in situ and in vitro results indicating the relevance of the latter even for environmental studies. Discharges from São Paulo city have major impact on genotoxic effects by sediment-bound contaminants; however, overall genotoxicity decreases downstream. The high genotoxic burden of the Tietê River warrants measures to reduce the input of toxic effluents.

Descriptions of morphological anomalies of phlebotomine sand flies (Diptera: Psychodidae) have been recorded in both the New World and the Old World. The majority of these anomalies are associated with the genitalia, the number of cibarial teeth, wing venation, the size of the palps, and other less significant features. Such morphological variations, particularly in symmetry, can result in incorrect species identification. The occurrence of gynandromorphism in sand flies is a rare phenomenon. Currently, only five such cases have been registered in worldwide literature. In Brazil, only one report of gynandromorphism was observed in a specimen of Lutzomyia longipalpis (Lutz & Neiva 1912) from the state of the Ceará. We report here on the first known case of gynandromorphism in Lutzomyia davisi (Root 1934) captured in Alta Floresta, Mato Grosso state, Brazil.

Perfluorooctane sulfonate (PFOS; C8F17SO3-) is a fully fluorinated organic compound which has been manufactured for decades and was used widely in industrial and commercial products. The recent toxicological knowledge of PFOS mainly concerns mono-substance exposures of PFOS to biological systems, leaving the potential interactive effects of PFOS with other compounds as an area where understanding is significantly lacking. However, a recent study, reported the potential of PFOS to enhance the toxicity of two compounds by increasing cell membrane permeability. This is of particular concern since PFOS has been reported to be widely distributed in the environment where contaminants are known to occur in complex mixtures. In this study, PFOS was evaluated alone and in combination with cyclophosphamide (CPP) to investigate whether a presence of PFOS leads to an increased genotoxic potential of CPP towards hamster lung V79 cells. Genotoxicity was investigated using the micronucleus (MN) assay according to the recent draft ISO/DIS 21427-2 method. PFOS alone demonstrated no genotoxicity up to a concentration of 12.5 microg/ml. However, PFOS combined with two different concentrations of CPP, with metabolic activation, caused a significant increase in the number of micronucleated cells compared to treatments with CPP alone. These results provide a first indication that PFOS has the potential to enhance the genotoxic action of CPP towards V79 cells, suggesting, together with the alterations in cell membrane properties shown previously, that genotoxicity of complex mixtures may be increased significantly by changes in chemical uptake. Together with an earlier study performed by the own working group, it can be concluded that PFOS alone is not genotoxic in this bioassay using V79 cells up to 12.5 microg/ml, but that further investigations are needed to assess the potential interaction between PFOS and other substances, in particular regarding the impact of membrane alterations on the uptake of toxic substances.

Genes introduced into higher plant genomes can become silent (gene silencing) and/or cause silencing of homologous genes at unlinked sites (homology-dependent gene silencing or HDG silencing). Mutations of the HOMOLOGY-DEPENDENT GENE SILENCING1 (HOG1) locus relieve transcriptional gene silencing and methylation-dependent HDG silencing and result in genome-wide demethylation. The hog1 mutant plants also grow slowly and have low fertility and reduced seed germination. Three independent mutants of HOG1 were each found to have point mutations at the 3' end of a gene coding for S-adenosyl-l-homocysteine (SAH) hydrolase, and hog1-1 plants show reduced SAH hydrolase activity. A transposon (hog1-4) and a T-DNA tag (hog1-5) in the HOG1 gene each behaved as zygotic embryo lethal mutants and could not be made homozygous. The results suggest that the homozygous hog1 point mutants are leaky and result in genome demethylation and poor growth and that homozygous insertion mutations result in zygotic lethality. Complementation of the hog1-1 point mutation with a T-DNA containing the gene coding for SAH hydrolase restored gene silencing, HDG silencing, DNA methylation, fast growth, and normal seed viability. The same T-DNA also complemented the zygotic embryo lethal phenotype of the hog1-4 tagged mutant. A model relating the HOG1 gene, DNA methylation, and methylation-dependent HDG silencing is presented.

The transition metal Zn is essential for many physiological processes in plants, yet at elevated concentrations this, and the related non-essential metal Cd, can be toxic. Arabidopsis thaliana HMA4, belonging to the Type P1B subfamily of P-type ATPases, has recently been implicated in Zn nutrition, having a role in root to shoot Zn translocation. Using Arabidopsis insertional mutants, it is shown here that disruption of AtHMA4 function also results in increased sensitivity to elevated levels of Cd and Zn, suggesting that AtHMA4 serves an important role in metal detoxification at higher metal concentrations. AtHMA4 and a truncated form lacking the last 457 amino acids both confer Cd and Zn resistance to yeast but a mutant version of the full-length AtHMA4 (AtHMA4-C357G) does not; this demonstrates that the C-terminal region is not essential for this function. Evidence is presented that AtHMA4 functions as an efflux pump.

Apyrases are nucleoside triphosphate-diphosphohydrolases that remove Pi from ATP and ADP. The blood feeding reduviid Triatoma infestans, which transmits the Trypanosoma cruzi agent of Chagas disease to animals and man, presents in its salivary glands five apyrases with molecular masses of 88, 82, 79, 68 and 67 kDa. These triatomine apyrases have been associated with the prevention of ADP induced platelet aggregation in the host. Here we provide biochemical data showing that these apyrases are stored in the lumen of the salivary gland D1 pairs, and that about one half of the pool of the enzyme is consumed during feeding. After the feeding recovery of apyrases to maximal activity level takes days, thus suggesting de novo protein synthesis. This hypothesis is supported by quantitative RT-PCR analysis which shows an upregulation of the 79 kDa apyrase mRNA level after feeding.

We describe the cytological features of a malignant phyllodes tumor, in a 40-yr-old female, that metastasized to the forearm, and we correlate these findings with the criteria suggested by other authors for predicting the clinical and metastatic behavior of this tumor. The diagnosis of metastasis was based on fine-needle aspiration (FNA) cytology. One year prior, the patient had undergone mastectomy of the left breast for malignant phyllodes tumor, as proven by histopathology. The patient then presented with right forearm swelling, 1 yr later. FNA cytology was performed, and the diagnosis was metastatic malignant phyllodes tumor. Histologic review of the breast tumor revealed stromal overgrowth, which is the most important histologic criterion for predicting the metastatic behavior of malignant phyllodes tumor as reported by some authors.

The exchange energy in the long-range near-dissociation region is analyzed for the ground electronic states of homo- and heteronuclear alkali diatomic molecules. The analysis is based on the use of the functional form Ae-ar to represent this exchange term. A period effect is observed in the values of both parameters and the exponent parameter a appears to approach an asymptotic limit for the heavier molecules. The results obtained in this study also suggest that some care must be taken in using even this function to represent the exchange energy. Copyright 1997 Academic Press. Copyright 1997Academic Press

The sequence of the intergenic spacer (IGS) of the Brassica rapa rDNA was determined and compared with those of other Cruciferae species. In the 3012-bp IGS, two segments of mostly unique sequence flank a 1.5-kb region consisting of two tandem arrays of repeats. A putative transcription initiation site (TIS) was identified by sequence comparison, 395 bp downstream from the repeat region. The intercalating segment displays unusual sequence patterns, and modelling of its topology predicts intrinsically bent DNA, with two elements of bending centered at positions -118 and -288 relative to the TIS. Comparative analysis of spacers from Cruciferae, revealed a common organization and high sequence similarity in their 5' and, particularly, 3' regions, whereas the repeat region upstream of TIS diverges rapidly. The conservation of structural elements, including the bent DNA upstream from the TIS, is discussed in light of their possible involvement in the IGS functions and structure of spacers in common ancestors. Examination of the Cruciferae spacers shows that, in addition to unequal crossover and gene conversion, insertional mutagenesis and replication slippage are molecular mechanisms significantly contributing to their evolution.

Canrep is a heterogeneous, tandemly repeated, 176 bp nucleotide sequence that contains a single Hind III site and is present in high copy numbers in the genomes of many Brassica species. Complete clusters of repeats of this DNA were cloned from the nuclear DNA of Brassica juncea. Restriction-fragment dimers and higher multimers of the 176 bp sequence have arisen by mutations within the Hind III recognition sequence. Adjacent repeats from within the same cluster usually have different nucleotide sequences with features indicating that diversity is generated by a mechanism that causes site-specific base substitutions. While most of the units of canrep DNA are clustered in long arrays of tandem repeats, some are dispersed throughout the genome as isolated copies or in small clusters. Regardless of the size of the arrays, each cluster begins and ends with a variable-length, truncated repeat and is flanked by inverted copies of the sequence 5'-ATCTCAT3'-, which is not part of the basic sequence of the canrep family of DNAs. Furthermore, some clusters are located close to nucleotide sequences related to those of known plant transposons. Thus, canrep elements may be dispersed by transposition. There are two distinct subfamilies of canrep sequences in B. juncea, and one of these is closely related to one of the two subfamilies of this type of DNA from B. napus, indicating that it originated from B. campestris, the common diploid ancestor of both amphidiploid species. Neither the repetitive DNA nor nucleotide sequences flanking canrep clusters are transcribed in seedlings, suggesting that even small arrays of repeats are located in heterochromatic regions and might be involved in chromatin condensation and/or chromosome segregation.

We present the case of an HIV-seropositive drug addict patient whose seropositivity was unknown until admission to hospital, where he presented with a clinical picture of fever splenomegaly and weight loss. A diagnosis of visceral leishmaniasis was established. We stress the diagnostic difficulties well expressed in the need to repeat the bone marrow aspirate to detect the presence of leishmanias. The lack of response to conventional antimonial therapy is discussed as well as the role of pentamidine as an alternative therapy.