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Malaria, caused by protozoa of the genus Plasmodium, is a disease that infects hundreds of millions of people annually, causing an enormous social burden in many developing countries. Since current antimalarial drugs are starting to face resistance by the parasite, the development of new therapeutic options has been prompted. The enzyme Plasmodium falciparum enoyl-ACP reductase (PfENR) has a determinant role in the fatty acid biosynthesis of this parasite and is absent in humans, making it an ideal target for new antimalarial drugs. In this sense, the present study aimed at evaluating the in silico binding affinity of natural and synthetic amides through molecular docking, in addition to their in vitro activity against P. falciparum by means of the SYBR Green Fluorescence Assay. The in vitro results revealed that the natural amide piplartine (1a) presented partial antiplasmodial activity (20.54 μM), whereas its synthetic derivatives (1m-IC 50 104.45 μM), (1b, 1g, 1k, and 14f) and the natural amide piperine (18a) were shown to be inactive (IC 50  > 200 μM). The in silico physicochemical analyses demonstrated that compounds 1m and 14f violated the Lipinski's rule of five. The in silico analyses showed that 14f presented the best binding affinity (- 13.047 kcal/mol) to PfENR and was also superior to the reference inhibitor triclosan (- 7.806 kcal/mol). In conclusion, we found that the structural modifications in 1a caused a significant decrease in antiplasmodial activity. Therefore, new modifications are encouraged in order to improve the activity observed.

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Background: Africa is experiencing a rapid increase in morbidity and mortality related to diabetes mellitus (DM). Contemporary data are needed to guide efforts to improve prevention and treatment for microvascular complications in children and adolescents in Africa. This study was conducted to assess prevalence of diabetic microvascular complications in northwestern Tanzania, including nephropathy, retinopathy, and neuropathy, as well as associated risk factors., Objectives: 1) To determine the prevalence of microvascular complications and the overlap of nephropathy, retinopathy and neuropathy and 2) to determine factors associated with the development of microvascular complications., Methods: This cross-sectional study included 155 children and adolescents with DM consecutively attending all three health centers providing diabetes care for children in the Mwanza region of Tanzania. Participants were examined for microvascular complications and possible risk factors., Results: Fifty-one of 155 participants (age: 5-19 years) had diabetic nephropathy (32.9%), 16 had diabetic retinopathy (10.3%), and 21 had diabetic neuropathy (13.6%). Risk factors for development of a microvascular complication included age, duration of DM, and poor glycemic control. Of the participants, 107 had poor levels of glycemic control (69%) with HbA1C levels >10%., Conclusion: The prevalence of microvascular complications, especially that of nephropathy, was disturbingly high. Risk factors for microvascular complications were similar to other studies from Africa and included poor glycemic control, older age, and longer duration of DM. Innovative, locally appropriate systems for optimizing glycemic control are urgently needed., Competing Interests: The authors have no competing interests to declare., (Copyright: © 2020 The Author(s).)

Studies in microbiology have long been mostly restricted to small spatial scales. However, recent technological advances, such as new sequencing methodologies, have ushered an era of large-scale sequencing of environmental DNA data from multiple biomes worldwide. These global datasets can now be used to explore long standing questions of microbial ecology. New methodological approaches and concepts are being developed to study such large-scale patterns in microbial communities, resulting in new perspectives that represent a significant advances for both microbiology and macroecology. Here, we identify and review important conceptual, computational, and methodological challenges and opportunities in microbial macroecology. Specifically, we discuss the challenges of handling and analyzing large amounts of microbiome data to understand taxa distribution and co-occurrence patterns. We also discuss approaches for modeling microbial communities based on environmental data, including information on biological interactions to make full use of available Big Data. Finally, we summarize the methods presented in a general approach aimed to aid microbiologists in addressing fundamental questions in microbial macroecology, including classical propositions (such as "everything is everywhere, but the environment selects") as well as applied ecological problems, such as those posed by human induced global environmental changes., (Copyright © 2020 Mascarenhas, Ruziska, Moreira, Campos, Loiola, Reis, Trindade-Silva, Barbosa, Salles, Menezes, Veiga, Coutinho, Dutilh, Guimarães, Assis, Ara, Miranda, Andrade, Vilela and Meirelles.)

Spinal cord injury (SCI) is a medical condition that currently lacks effective treatment. Galantamine is a reversible, competitive acetylcholinesterase inhibitor, used to treat patients with Alzheimeŕs disease. It has been demonstrated that galantamine increases cerebral neurogenesis and has a neuroprotective effect by binding to nicotinic receptors and has an anti-inflammatory effect due to its allosteric binding to the α7nAChR. In the present study, the effects of galantamine on functional recovery and histological outcome in a rat contusion model of SCI were analyzed. Male Wistar rats were submitted to SCI using a NYU/MASCIS impactor. The animals from the galantamine group were treated with 5 mg/kg galantamine intraperitoneally for 5 days. The Basso, Beattie and Bresnahan scale (BBB) was used to evaluate locomotor activity. The expression of beta3-tubulin, NFM, GFAP, O4, CD68 and CD3 was analyzed by flow cytometry. Rats that received galantamine had significantly higher BBB scores in comparison with the control lesion group. Galantamine treatment increased the percentage of NFM positive cells at 6 weeks post-injury and reduced the size of the lesion. The results indicate that galantamine increased tissue survival and accelerated hind limb motor function recovery. This is the first study that has shown the possibility of therapeutic use of galantamine in a model of acute spinal cord injury., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Schizophrenia, Schizoaffective, and Bipolar disorders share behavioral and phenomenological traits, intermediate phenotypes, and some associated genetic loci with pleiotropic effects. Volumetric abnormalities in brain structures are among the intermediate phenotypes consistently reported associated with these disorders. In order to examine the genetic underpinnings of these structural brain modifications, we performed genome-wide association analyses (GWAS) on 60 quantitative structural brain MRI phenotypes in a sample of 777 subjects (483 cases and 294 controls pooled together). Genotyping was performed with the Illumina PsychChip microarray, followed by imputation to the 1000 genomes multiethnic reference panel. Enlargement of the Temporal Horns of Lateral Ventricles (THLV) is associated with an intronic SNP of the gene NRXN1 (rs12467877, P = 6.76E-10), which accounts for 4.5% of the variance in size. Enlarged THLV is associated with psychosis in this sample, and with reduction of the hippocampus and enlargement of the choroid plexus and caudate. Eight other suggestively significant associations (P < 5.5E-8) were identified with THLV and 5 other brain structures. Although rare deletions of NRXN1 have been previously associated with psychosis, this is the first report of a common SNP variant of NRXN1 associated with enlargement of the THLV in psychosis.

The aim was to evaluate the effect of the ethanol extract of bacupari peel (EEB) on biometric measurements, hepatic lipogenesis and progression of non-alcoholic fatty liver disease (NAFLD) in obese Wistar rats. Chemical analysis of the bacupari peel extract identified 7-epiclusianone as the major constituent (140.02 mg/g) followed by morelloflavone (35.86 mg/g). Animals treated with high fat diet plus EEB (BHFD) reduced body mass index (BMI), liver weight and hepatosomatic index in relation to the obese control. The food intake was similar between hyperlipid group (HFD) groups with or without EEB. However, the normal control group (AIN-93 M) presented higher food intake and lower final weight compared to the obese control (HFD). The PPAR-α, CPT-1a and the ADIPOR2 genes expressions, and the concentration of the PPAR-α and the adiponectin protein level increased in the BHFD group in relation to the obese control. The EEB promoted reduction of the SREBP-1c gene expression and the percentage of hepatic fat and the degree of steatosis in relation to HFD. It was concluded that EEB showed a protective effect on NAFLD, as it promoted a reduction in BMI, induced lipid oxidation, reduced lipogenesis and hepatic steatosis. Moreover, our results suggest an interaction that can lead to an agonist activity of the EEB to the PPAR-α receptor., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

The study investigated the effect of extruded sorghum flour (ESF) in a high fat diet (HFD) on biometric measurements and hepatic lipogenesis. Male Wistar rats were fed a normal diet (AIN-93M), HFD, HFD plus ESF replacing 50% cellulose and 100% corn starch (HFDS50), or HFD plus ESF replacing 100% cellulose and 100% corn starch (HFDS100) for eight weeks. ESF reduced the body mass index and liver weight of obese rats. Additionally, ESF reduced hepatic lipogenesis by increasing adiponectin 2 receptor gene expression and gene and protein expressions of peroxisome proliferator-activated receptor α (PPARα), while reducing the gene expression of sterol regulatory element-binding transcription factor 1. Molecular docking analysis revealed the affinity of ESF compounds (luteolinidin, apigeninidin, 5-methoxy-luteolinidin, and 7-methoxy-apigeninidin) with the PPAR-α receptor. Histological analysis confirmed the decreased grade of hepatic steatosis in obese rats. These data indicate the potential of ESF to reduce metabolic risk of hepatic steatosis associated with lipogenesis and obesity., (Copyright © 2018. Published by Elsevier Ltd.)

The atypical Rho GTPase RhoD has previously been shown to have a major impact on the organization and function of the actin filament system. However, when first discovered, RhoD was found to regulate endosome trafficking and dynamics and we therefore sought to investigate this regulation in more detail. We found that exogenously expressed RhoD in human fibroblasts localized to vesicles and the plasma membrane and that the active GTP-bound conformation was required for the plasma membrane localization but not for vesicle localization. In contrast to the GTPase deficient atypical Rho GTPases, which have a stalled GTPase activity, RhoD has an elevated intrinsic GDP/GTP exchange activity, rendering the protein constitutively active. Importantly, RhoD can still hydrolyze GTP and we found that an intact GTPase activity was required for efficient fusion of RhoD-positive vesicles. RhoD has a unique N-terminal extension of 14 amino acid residues, which is not present in the classical Rho GTPases RhoA, Cdc42 and Rac1. Deletion of this N-terminal motif often lead to clustering of RhoD positive vesicles, which were found accumulated at the peripheral membrane border. In addition, the number of vesicles per cell was increased manifold, suggesting that the N-terminal motif has an important regulatory role in vesicle dynamics., (Copyright © 2018 Elsevier GmbH. All rights reserved.)

Sugar cane is an important crop for sugar and biofuel production. Its lignocellulosic biomass represents a promising option as feedstock for second-generation ethanol production. Nitrogen fertilization can affect differently tissues and its biopolymers, including the cell-wall polysaccharides and lignin. Lignin content and composition are the most important factors associated with biomass recalcitrance to convert cell-wall polysaccharides into fermentable sugars. Thus it is important to understand the metabolic relationship between nitrogen fertilization and lignin in this feedstock. In this study, a large-scale proteomics approach based on GeLC-MS/MS was employed to identify and relatively quantify proteins differently accumulated in two contrasting genotypes for lignin composition after excessive nitrogen fertilization. From the ∼1000 nonredundant proteins identified, 28 and 177 were differentially accumulated in response to nitrogen from IACSP04-065 and IACSP04-627 lines, respectively. These proteins were associated with several functional categories, including carbon metabolism, amino acid metabolism, protein turnover, and oxidative stress. Although nitrogen fertilization has not changed lignin content, phenolic acids and lignin composition were changed in both species but not in the same way. Sucrose and reducing sugars increased in plants of the genotype IACSP04-065 receiving nitrogen.

Impaired DNA replication is a hallmark of cancer and a cause of genomic instability. We report that, in addition to causing genetic change, impaired DNA replication during embryonic development can have major epigenetic consequences for a genome. In a genome-wide screen, we identified impaired DNA replication as a cause of increased expression from a repressed transgene in Caenorhabditis elegans . The acquired expression state behaved as an "epiallele," being inherited for multiple generations before fully resetting. Derepression was not restricted to the transgene but was caused by a global reduction in heterochromatin-associated histone modifications due to the impaired retention of modified histones on DNA during replication in the early embryo. Impaired DNA replication during development can therefore globally derepress chromatin, creating new intergenerationally inherited epigenetic expression states.

RhoD belongs to the Rho GTPases, a protein family responsible for the regulation and organization of the actin cytoskeleton, and, consequently, many cellular processes like cell migration, cell division and vesicle trafficking. Here, we demonstrate that the actin cytoskeleton is dynamically regulated by increased or decreased protein levels of RhoD. Ectopic expression of RhoD has previously been shown to give an intertwined weave of actin filaments. We show that this RhoD-dependent effect is detected in several cell types and results in a less dynamic actin filament system. In contrast, RhoD depletion leads to increased actin filament-containing structures, such as cortical actin, stress fibers and edge ruffles. Moreover, vital cellular functions such as cell migration and proliferation are defective when RhoD is silenced. Taken together, we present data suggesting that RhoD is an important component in the control of actin dynamics and directed cell migration., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Objective: This study sought to evaluate the effect of the penetration of an epoxy resin-based root canal sealer into dentin tubules on the force required to dislodge the root canal filling., Methods: Sixty extracted human central incisors with single canals were decoronated, instrumented, and filled with gutta-percha and AH Plus sealer labeled with 0.1% rhodamine B dye. The roots were further sectioned horizontally at 3, 6, and 8 mm from the apex. The coronal surfaces of the resulting 180 slices were evaluated using confocal laser scanning microscopy to measure the amount of sealer that penetrated into the dentin tubules. To quantify the force required to dislocate the root filling material, the root fillings of the slices were subjected to a dislodgement resistance test (push-out). Spearman's rho correlation test was further used to test the correlation between the push-out bond strength and sealer penetration into the dentin tubules (P<0.05)., Results: No significant correlation was observed between sealer penetration into the dentin tubules and the force required to dislodge the root canal filling (P=0.626)., Conclusion: Following the results of this study, the penetrating ability of the AH Plus sealer into dentin tubules has no correlation with the force required to dislodge the root canal filling., Competing Interests: Conflict of Interest: No conflict of interest was declared by the authors., (Copyright: © 2020 European Endodontic Journal.)

RHO GTPase-activating proteins (RHOGAPs) are one of the major classes of regulators of the RHO-related protein family that are crucial in many cellular processes, motility, contractility, growth, differentiation, and development. Using database searches, we extracted 66 distinct human RHOGAPs, from which 57 have a common catalytic domain capable of terminating RHO protein signaling by stimulating the slow intrinsic GTP hydrolysis (GTPase) reaction. The specificity of the majority of the members of RHOGAP family is largely uncharacterized. Here, we comprehensively investigated the sequence-structure-function relationship between RHOGAPs and RHO proteins by combining our in vitro data with in silico data. The activity of 14 representatives of the RHOGAP family toward 12 RHO family proteins was determined in real time. We identified and structurally verified hot spots in the interface between RHOGAPs and RHO proteins as critical determinants for binding and catalysis. We have found that the RHOGAP domain itself is nonselective and in some cases rather inefficient under cell-free conditions. Thus, we propose that other domains of RHOGAPs confer substrate specificity and fine-tune their catalytic efficiency in cells., (© 2016 by The American Society for Biochemistry and Molecular Biology, Inc.)

Genes coding for members of the Sm-like (LSm) protein family are conserved through evolution from prokaryotes to humans. These proteins have been described as forming homo- or heterocomplexes implicated in a broad range of RNA-related functions. To date, the nuclear LSm2-8 and the cytoplasmic LSm1-7 heteroheptamers are the best characterized complexes in eukaryotes. Through a comprehensive functional study of the LSm family members, we found that lsm-1 and lsm-3 are not essential for C. elegans viability, but their perturbation, by RNAi or mutations, produces defects in development, reproduction, and motility. We further investigated the function of lsm-1, which encodes the distinctive protein of the cytoplasmic complex. RNA-seq analysis of lsm-1 mutants suggests that they have impaired Insulin/IGF-1 signaling (IIS), which is conserved in metazoans and involved in the response to various types of stress through the action of the FOXO transcription factor DAF-16. Further analysis using a DAF-16::GFP reporter indicated that heat stress-induced translocation of DAF-16 to the nuclei is dependent on lsm-1. Consistent with this, we observed that lsm-1 mutants display heightened sensitivity to thermal stress and starvation, while overexpression of lsm-1 has the opposite effect. We also observed that under stress, cytoplasmic LSm proteins aggregate into granules in an LSM-1-dependent manner. Moreover, we found that lsm-1 and lsm-3 are required for other processes regulated by the IIS pathway, such as aging and pathogen resistance., (© 2015 Cornes et al.; Published by Cold Spring Harbor Laboratory Press for the RNA Society.)

Although chromosome partitioning during mitosis is well studied, the molecular mechanisms that allow proper segregation of cytoplasmic organelles in human cells are poorly understood. Here we show that mitochondria interact with growing microtubule tips and are transported towards the daughter cell periphery at the end of mitosis. This phenomenon is promoted by the direct and cell cycle-dependent interaction of the mitochondrial protein Miro and the cytoskeletal-associated protein Cenp-F. Cenp-F is recruited to mitochondria by Miro at the time of cytokinesis and associates with microtubule growing tips. Cells devoid of Cenp-F or Miro show decreased spreading of the mitochondrial network as well as cytokinesis-specific defects in mitochondrial transport towards the cell periphery. Thus, Miro and Cenp-F promote anterograde mitochondrial movement and proper mitochondrial distribution in daughter cells.

RhoD is a member of the Rho GTPase family and it coordinates actin dynamics and membrane trafficking. Activation of RhoD results in formation of filopodia, dissolution of stress fibers, and the subsequent formation of short actin bundles. In addition, RhoD localizes to early endosomes and recycling endosomes, and has a regulatory role in endosome trafficking. In this study, we report on a function of RhoD in the regulation of Golgi homeostasis. We show that manipulation of protein and activation levels of RhoD, as well as of its binding partner WHAMM, result in derailed localization of Golgi stacks. Moreover, vesicle trafficking from the endoplasmic reticulum to the plasma membrane via the Golgi apparatus measured by the VSV-G protein is severely hampered by manipulation of RhoD or WHAMM. In summary, our studies demonstrate a novel role for this member of the Rho GTPases in the regulation of Golgi function., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Cellulose at the nanoparticle scale has been studied as a reinforcement for biodegradable matrices to improve film properties. The goal has been to investigate the properties of starch/gelatin/cellulose nanocrystals (CNC) films. Eleven treatments were considered using RCCD (rotatable central composite design), in addition to four control treatments. For each assay, the following dependent variables were measured: water vapor permeability (WVP), thickness, opacity and mechanical properties. The microstructure and thermal properties of the films were also assessed. Increases in gelatin and CNC concentrations lead to increases in film thickness, strength and elongation at break. The films containing only gelatin in their matrix displayed better results than the starch films, and the addition of CNC had a positive effect on the assessed response variables. The films exhibited homogeneous and cohesive structures, indicating strong interactions between the filler and matrix. Films with low levels of gelatin and CNC presented the maximum degradation temperature., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Understanding the in vivo dynamics of protein localization and their physical interactions is important for many problems in biology. To enable systematic protein function interrogation in a multicellular context, we built a genome-scale transgenic platform for in vivo expression of fluorescent- and affinity-tagged proteins in Caenorhabditis elegans under endogenous cis regulatory control. The platform combines computer-assisted transgene design, massively parallel DNA engineering, and next-generation sequencing to generate a resource of 14,637 genomic DNA transgenes, which covers 73% of the proteome. The multipurpose tag used allows any protein of interest to be localized in vivo or affinity purified using standard tag-based assays. We illustrate the utility of the resource by systematic chromatin immunopurification and automated 4D imaging, which produced detailed DNA binding and cell/tissue distribution maps for key transcription factor proteins., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Central nervous system dysfunctions are among the most significant effects of exposure to ethanol and the glial cells that play an important role in maintaining neuronal function, are extremely involved with these effects. The actin cytoskeleton plays a crucial role in a wide variety of cellular functions, especially when there is some injury. Therefore the aim of the present study was to analyze the short-term effects of ethanol (50, 100 and 200 mM) on the cytoskeleton of C6 glioma cells. Here we report that acute ethanol exposure profoundly disrupts the actin cytoskeleton in C6 cells decreasing stress fiber formation and downregulating RhoA and vinculin immunocontent. In contrast, microtubule and GFAP networks were not altered. We further demonstrate that anti-oxidants prevent ethanol-induced actin alterations, suggesting that the actions of ethanol on the actin cytoskeleton are related with generation of reactive oxygen species (ROS) in these cells. Our results show that ethanol at concentrations described to be toxic to the central nervous system was able to target the cytoskeleton of C6 cells and this effect could be related with increased ROS generation. Therefore, we propose that the dynamic restructuring of the cytoskeleton of glial cells might contribute to the response to the injury provoked by binge-like ethanol exposure in brain., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

Activated microglia cells, observed during chronic inflammation, produce and secrete compounds that at high concentrations or during sustained production might cause neuronal cell death. Inducible nitric oxide synthase (iNOS) is expressed in response to various immunological stimuli and catalyses the formation of the free radical nitric oxide (NO), that at low and regulated levels participate in cell signaling and cytoprotective events, whereas its higher and unregulated production can promote neurotoxicity in cells or in tissues. Regulation of NO production is therefore central for maintaining NO-levels within a safe window. We have analyzed iNOS protein expression and NO production, in murine microglial Bv-2 cells after 16h treatment with the bacterial endotoxin lipopolysaccharide (LPS). We have further analyzed three MAPK pathways, by co-treating the cells with LPS and the inhibitors of ERK1/2, p38 or JNK MAPK activities. To investigate participation of an oxidative regulatory mechanism, cells were also treated with the antioxidant N-acetyl-L-cysteine (NAC). Our results show that LPS-induced iNOS expression in Bv-2 cells is mainly mediated through JNK MAPK. In addition, co-treatment of the Bv-2 cells with LPS and NAC surprisingly further increased the iNOS expression, an effect also found to be mediated through the JNK MAPK pathway. The level of phosphorylated JNK MAPK (p46) was strongly increased by LPS alone and was further increased when combined with NAC. Our data indicate that iNOS and NO production are suppressed by an oxidative mechanism acting on the JNK MAPK pathway and we speculate that it might constitute a potential regulatory mechanism controlling the NO level., (Copyright 2010 Elsevier B.V. All rights reserved.)

Mitochondria are organelles of elaborate structure that in addition to supplying cellular energy, have significant roles in calcium homeostasis and apoptosis. Failure to maintain mitochondrial dynamics results in neurodegenerative diseases and neuromuscular pathologies. The Miro GTPases, which constitute a unique subgroup of the Ras superfamily, have emerged as essential regulators of mitochondrial morphogenesis and trafficking along microtubules. Miro GTPases function as calcium-dependent sensors in the control of mitochondrial motility. Increased awareness of the biological function of Miro GTPases can contribute to elucidate the molecular mechanisms underlying diseases caused by deregulated mitochondrial dynamics.

Introduction: Adiponectin is increased in end-stage renal disease. However, efforts to clarify the cause of that increase and its clinical effects have been inconclusive. The aim of this study was to compare serum adiponectin levels of dialysis patients against healthy individuals and evaluate the relationship among adiponectin levels, IL-6, TNF- alpha and left ventricular mass index (LVMI)., Methods: Adiponectin, IL-6 and TNF- alpha measurements and echocardiographic evaluations were performed in 36 hemodialysis, 30 continuous ambulatory peritoneal dialysis (CAPD) patients and 22 healthy volunteers. Adiponectin, IL-6 and TNF- alpha levels were measured by ELISA., Results: Adiponectin was found to be higher in hemodialysis (52.78+/-18.01 ng/mL) and CAPD (52.96+/-17.53 ng/mL) groups than controls (28.36+/-13.20 ng/ mL; p=0.0003, p=0.0003, respectively). No difference was observed between the hemodialysis and CAPD groups. Adiponectin was positively correlated with IL-6 (r=0.293, p=0.02), TNF- alpha (r=0.458, p=0.0003) and LVMI (r=0.283, p=0.02). In the partial correlation analysis, by controlling for body mass index, the correlation between adiponectin and TNF- alpha (r=0.466, p=0.0003) persisted. When IL-6 was controlled with TNF- alpha, the relation between adiponectin and LVMI disappeared (r=0.145, p=0.30). In the linear regression analysis, with adiponectin as the dependent variable, and IL-6, TNF- alpha and body mass index as independent variables, a significant relationship was found between adiponectin and TNF- alpha (beta=0.488, p=0.001)., Conclusions: Increased adiponectin seems to be associated with increased proinflammatory cytokines in dialysis patients, and this relationship suggests adiponectin may have a role in the development of left ventricular hypertrophy.

The activation of cellular inflammatory response is tightly linked to induced production of reactive oxygen species (ROS) and nitric oxide (NO), which in turn have been identified as important regulators of cellular iron metabolism. In the present study, we have used the microglia cell line BV-2 and the neuroblastoma cell line N2a to study the regulatory effects of the microbial agent lipopolysaccharide (LPS) on the expression of the transferrin receptor (TfR) and ferritin in cell lines with different characteristics. The receptor mainly responsible for LPS recognition is the Toll-like receptor 4 (TLR4) that triggers a variety of intracellular signalling cascades leading to the induction of transcription of target genes involved in the innate immune response. Among the pathways to be activated is the MAPK cascade leading to the activation of nuclear factor-kappaB that induces transcription of a variety of genes, e.g., inducible nitric oxide synthase (iNOS). The TLR4-mediated LPS response also induces the production of ROS through a mechanism(s) suggested to involve the activation of NADPH oxidase(s). This study shows that exposure of BV-2 and N2a cells to LPS results in decreased TfR protein levels and increased H-ferritin mRNA levels. The LPS down-regulatory effect on TfR protein expression is abolished by the NADPH oxidase inhibitor diphenyliodonium (DPI) but is not affected by the free radical scavenger N-acetyl-L-cysteine (NAC) or the iNOS inhibitor aminoguanidine (AG). The increased H-ferritin mRNA levels in response to LPS are not affected by DPI, NAC, or AG., (Copyright 2006 Wiley-Liss, Inc.)

We have been able to label the excretory system of cercariae and all forms of schistosomula, immature and adult worms with the highly fluorescent dye resorufin. We have shown that the accumulation of the resorufin into the excretory tubules and collecting ducts of the male adult worm depends on the presence of extracellular calcium and phosphate ions. In the adult male worms, praziquantel (PZQ) prevents this accumulation in RPMI medium and disperses resorufin from tubules which have been prelabelled. Female worms and all other developmental stages are much less affected either by the presence of calcium and phosphate ions, or the disruption caused by PZQ. The male can inhibit the excretory system in paired female. Fluorescent PZQ localises in the posterior gut (intestine) region of the male adult worm, but not in the excretory system, except for the anionic carboxy fluorescein derivative of PZQ, which may be excreted by this route. All stages of the parasite can recover from damage by PZQ treatment in vitro. The excretory system is highly sensitive to damage to the surface membrane and may be involved in vesicle movement and damage repair processes. In vivo the adult parasite does not recover from PZQ treatment, but what is inhibiting recovery is unknown, but likely to be related to immune effector molecules.

The molecular mechanism of neurodegeneration in prion diseases remains largely uncertain, but one of the features of infected cells is higher sensitivity to induced oxidative stress. In this study, we have investigated the role of iron in hydrogen peroxide (H(2)O(2))-induced toxicity in scrapie-infected mouse neuroblastoma N2a (ScN 2 a) cells. ScN 2 a cells were significantly more susceptible to H(2)O(2) toxicity than N2a cells as revealed by cell viability (MTT) assay. After 2h exposure, significant decrease in cell viability in ScN 2 a cells was observed at low concentrations of extracellular H(2)O(2) (5-10 microM), whereas N2a cells were not affected. The increased H(2)O(2) toxicity in ScN 2 a cells may be related to intracellular iron status since ferrous iron (Fe(2+)) chelator 2,2'-bipyridyl (BIP) prevented H(2)O(2)-induced decrease in cell viability. Further, the level of calcein-sensitive labile iron pool (LIP) was significantly increased in ScN 2 a cells after H(2)O(2) treatment. Finally, the production of reactive oxygen species (ROS) was inhibited by 30% by iron chelators desferrioxamine (DFO) and BIP in ScN 2 a cells, whereas no significant effect of iron chelators on basal ROS production was observed in N2a cells. This study indicates that cellular resistance to oxidative stress in ScN 2 a cells is associated with intracellular status of reactive iron.

The latency and variability of latency of single-unit responses to identical visual stimulation were measured in the frontal eye field (FEF), supplementary eye field (SEF), and anterior cingulate cortex (ACC) of macaque monkeys performing visually guided saccades. The mean visual response latency was significantly shorter in FEF (64 ms) than in SEF (81 ms) or ACC (100 ms), and latency values determined by four methods agreed. The latency variability of the visual response was respectively less in FEF (21 ms) than in SEF (37 ms) or ACC (41 ms). Latency, variability of latency, and magnitude of the visual responses were correlated within FEF and SEF but not ACC. These characteristics of the visual response are consistent with the degree of convergence of visual afferents to these areas and constrain hypotheses about visual processing in the frontal lobe.

Chronic allograft dysfunction (CAD) is the most common cause of allograft failure in the long-term, and current immunologic strategies have little effect on this condition. The renin-angiotensin system (RAS) plays important roles progression of chronic renal disease. It is thought that plasminogen activator inhibitor-1 (PAI-1) functions in the RAS, in addition to involvement in thrombotic risk and fibrosis. This study investigated possible links between angiotensinogen (AGT) genotypes (M235T/MM, MT, TT) and PAI-1 genotypes (4G4G, 4G5G, 5G5G) and CAD assessments of both types of polymorphism were performed in 82 renal allograft recipients. One hundred healthy subjects were also investigated for AGT polymorphism, and 80 healthy subjects for PAI-1 polymorphism. Genotypes were determined using polymerase chain reaction (PCR) sequence-specific primers, and PCR followed by restriction fragment length polymorphism analysis. Kidney recipients with CAD had significantly lower frequencies of the MM genotype and the M allele than the recipients without CAD (p < 0.05 and <0.001). The transplant recipients with CAD also had significantly lower frequencies of the 5G5G genotype and the 5G allele than those without CAD (p < 0.001 and <0.05). Determination of AGT M235T and PAI-1 genotypes prior to transplantation may help identify patients who at risk for chronic renal transplant dysfunction.

We report the effects of amyloid precursor protein (APP) fragment 714-723 (APP(714-723); peptide P1) and its V717F and V717G mutants (peptides P2 and P3, respectively) on G-protein activity ([35S]GTPgammaS binding) in membranes from postmortem human control and Alzheimer's disease (AD) brains. The peptides P1, P2, and P3 revealed a significant stimulatory effect on [35S]GTPgammaS binding in control temporal cortex. The most potent stimulator, P3, at 10 microM concentration enhanced [35S]GTPgammaS binding by 500%. The effect was threefold stronger than that for wild-type P1 and twofold stronger than that for P2. In sporadic AD, the stimulatory effect of P1, P2, and P3 on G-proteins was reduced significantly whereas in Swedish familial AD (SFAD), only P1 elicited marked stimulation (at 10 microM by 50%). In control sensory postcentral cortex, the stimulation of G-proteins by P3 was 1.5-fold lower than that in control temporal cortex, whereas in AD and SFAD the effect showed no remarkable regional difference. Treatment of membranes with H2O2 produced 1.5-fold higher stimulation in [35S]GTPgammaS binding to temporal cortex than that in binding to sensory postcentral cortex. In AD and SFAD, the stimulation by H2O2 revealed no significant regional difference. Glutathione, desferrioxamine (DFO), and 17beta-estradiol markedly decreased the strong stimulatory effect by P3 on [35S]GTPgammaS binding to control temporal cortex, with the protective effect by DFO being most potent. The G(alphaO)-protein levels were not changed in AD or SFAD brain membranes as compared to levels in control membranes. We suggest that strong G-protein stimulation by P3 in the human brain implies the specific (per)oxidation mechanism that might be affected by regional content of peroxidizing substrates and antioxidants.

This study was performed to investigate the potential relationship between left ventricular hypertrophy (LVH) and proinflammatory cytokines in hemodialysis (HD) patients and the effect of HD on cytokine production. Serum interleukin 1 beta (IL-1 beta), interleukin 6 (IL-6) and tumor necrosis factor alpha (TNF-alpha) measurements and echocardiographic studies were performed in 35 stable HD patients. A variety of probable risk factors for LVH including age, HD duration, blood pressure (BP), body mass index, lipid profile, hemoglobin, albumin, parathormone and homocysteine levels were also investigated. Additionally, the effect of HD procedure on cytokine levels was evaluated. Predialysis serum levels of IL-1beta, IL-6, TNF-alpha, and homocysteine in HD patients were compared with 12 healthy subjects. Left ventricular hypertrophy was demonstrated in 20 (57%) of HD patients by echocardiography. Left ventricular mass index (LVMI) was correlated positively with systolic BP (r=0.556, p=0.001), diastolic BP (r=0.474, p=0.004), and serum levels of TNF-alpha (r=0.446, p=0.009). Multiple regression analysis showed that systolic BP and TNF-alpha levels were significant independent predictors of LVH. No relationship was observed between LVH and other parameters. The mean predialysis serum level of IL-6 was significantly higher in HD patients compared to healthy controls (15.7 +/- 8.7 vs. 7.3 +/- 0.7 pg/ mL, p=0.001). Predialysis serum levels of TNF-alpha in HD patients were higher when compared to healthy subjects, but the difference was not statistically significant (8.3 +/- 3 vs. 7 +/- 1.45 pg/mL, respectively, p>0.05). However, serum levels of IL-6 and TNF-alpha significantly elevated after HD, when compared to predialysis levels (from 15.7 +/- 8.7 to 17.8 +/- 9.5 pg/mL, p=0.001 and from 8.3 +/- 3.0 to 9.9 +/- 3.5 pg/mL p=0.004, respectively). As a conclusion, in addition to BP, proinflammatory cytokines, TNF-alpha in particular, seem to be associated with LVH in ESRD patients.

A new system for typing and screening blood, based on the sieving effect of glass bead microparticles, has been developed. The test is performed in a microcolumn in which the red cell agglutinates are trapped in the glass bead matrix during centrifugation, and unagglutinated cells form a pellet at the bottom of the column. Anti-human globulin reagents were incorporated in the diluent and the new test system, column agglutination technology, was compared to conventional tube tests and low-ionic-strength method. Sera and plasmas (228 samples) were screened for red cell antibodies with two anti-human globulin reagents: one containing only anti-IgG and the other containing both anti-IgG and anti-C3b, -C3d. After initial testing, there was 94-percent agreement between column agglutination technology and tube tests, and after repeat testing, there was 97-percent agreement. The column agglutination technology anti-human globulin test eliminates the need to wash red cells, which decreases the overall test time. The test is easy to perform, and the results are more objective than those with tube and microplate methods.

An extensive and severe actinomycetoma by Nocardia asteroides, a rare etiologic agent of this infection in Brazil, observed during a 9 year follow-up is reported. Unsuitable social and financial conditions led to amputation as the only possible solution for this case, no signs of infection relapse having been observed in three years after his surgery.

Blood monocytes and alveolar macrophages (AM) were harvested from foals (aged 46 days to 6 months) and cultured in either medium alone or medium containing 10 micrograms/ml bacterial lipopolysaccharide (LPS). After 24 h, culture supernates were collected and analyzed for cytotoxic activity on sensitized L929 cells. Both monocytes and AM that had been treated with LPS produced significantly more cytotoxic activity than the same cell type exposed to medium lacking LPS. LPS-treated macrophages secreted significantly more cytotoxic activity (120 +/- 17.8 U/ml) than did LPS-treated monocytes (47.3 +/- 17.0 U/ml); however, constitutive production of cytotoxin by monocytes was higher (16.7 +/- 4.1 versus 1.2 +/- 1.2 U/ml). The identification of the cytotoxin as tumor necrosis factor (TNF) was strongly suggested by its reactivity with a rabbit antiserum directed against the N-terminal 15 amino acids of human TNF. TNF secretion by AM increased in a dose-dependent manner between LPS concentrations of 0.0001 and 1 microgram/ml, then leveled off. Most of the cytotoxic TNF activity produced by AM was secreted within the first 8 h after initial contact with LPS. Macrophage supernatant TNF was stable over a pH range of 6-11, but lost activity when kept at a pH less than 6. Equine TNF also was destroyed by exposure for 1 h to temperatures more than 60 degrees C. TNF bioactivity was recovered as a single peak after crude macrophage supernate was subjected to analysis by either anion exchange or gel filtration chromatography (molecular weight approximately 56,000).

Considering the number of birth a special problem of "adolescent pregnants" is not presently valid in the GDR. Studying the health behavior however it becomes obvious that there are existing positive and negative differences, as well. On the contraceptive behaviour of adolescents must be set a careless value. The pregnancies therefore are planned more seldom. Adolescent pregnants smoke more frequent than older ones. This is valid before and during pregnancy, as well. Younger and also older pregnants pay only small attention to sporting activities. Younger ones however are more conscious with regard to nutrition, relaxation after work and body hygiene. Health educational tasks are outlined.

The interaction of type I (staphylococcal protein A) and type III (streptococcal FcRc) bacterial Fc receptors with goat immunoglobulins has been studied. Staphylococcal protein A bound poorly to the majority of goat immunoglobulins at all pHs tested. There was some evidence that protein A bound IgG2 better than IgG1, particularly at pH 8 and above. One of 10 sera tested demonstrated a high level of reactivity with protein A and this was shown to correlate with the presence of a natural antibody to protein A. The streptococcal Fc receptors, FcRc, bound efficiently to all goat IgG and goat sera tested. Both goat IgG subclasses reacted efficiently with the FcRc between pH 6 and 8. Inhibition of binding of 125I-FcRc to immobilized goat IgG enabled levels of IgG in goat serum to be estimated. These results suggest the streptococcal FcRc will be of value as an immunochemical reagent in studies involving isolation and quantitation of goat immunoglobulins.

The structural similarity between staphylococcal protein A and streptococcal Fc receptors was examined. Antibody to staphylococcal protein A, proven not to bind to protein A through Fc, was used to determine if the Fc receptors on 4 Fc-receptor positive streptococcal strains were antigenically related to staphylococcal protein A. Anti-protein A antibody bound to Staphylococcus aureus Cowan I, but failed to bind to any of the streptococci. Additionally, when the Cowan strain and 9 other Staphylococcus aureus isolates demonstrating various levels of IgG adsorption capacity were preincubated with antiprotein A antibody, the ability of these bacteria to adsorb IgG was completely inhibited. These results suggest that all the Fc receptors on Staphylococcus aureus are antigenically similar or identical to protein A. Fc receptors on streptococci, while sharing with staphylococcal protein A the capacity to bind to Fc of human IgG, were not antigenically crossreactive with protein A.

A hemolytic assay was developed for the measurement of functional equine complement activity. The assay utilizes antibody sensitized chicken erythrocytes as the target cell and was specific for classical pathway (antibody dependent) complement activity. The assay was found to be reproducible and more sensitive than previous reports using other species of target cells. Total serum complement (CH50) values were determined for five mares and their foals and followed over a period of 3 months.

Evidence has been produced to higher risk for unmarried pregnant women to deliver children with low birth weight, with reference being made to the files of the Gynaecological Hospital of the Region of Schwerin and, more particularly, to single live births, between 1969 and 1977. That higher risk was found to depend on other factors, as well, with particular emphasis on residence and occupation. The risk, however, was found to be lowered, when it came to second births and decline in the rate of low birth weight, in the context of unmarried mothers. Yet, the decline was less strong, as compared to married mothers, and the risk associated with unmarried women, consequently, remains to be regularly 60 per cent above average. These findings are considered by the authors as being relevant to supervision and guidance of women during pregnancy.

Many bacterial surface receptors demonstrate a heterogeneous expression pattern among individual colonies. Methods have been developed to select bacteria expressing high levels of a stable surface receptor. This process is illustrated using a Streptococcus zooepidemicus isolate demonstrating a high level of Fc receptors for rat immunoglobulins. This strain was selected and expanded to obtain a bacterial isolate demonstrating approximately 100 fold greater reactivity with rat immunoglobulins than protein A positive Staphylococcus aureus or 30-40 fold higher reactivity for rat IgG than type III Fc receptor positive streptococcal group G strains. The optimal pH for rat IgG binding and the reactivity with rat IgG subclasses and certain rat monoclonal antibodies is described. The potential application and limitations of the selected rat Fc receptor positive bacterial strain to immunoassays based on the specificity of rat monoclonal and polyclonal antibodies is discussed.