bluuebunny/crossref_metadata_2025 huggingface dataset:
Transcriptional profile reveals altered hepatic lipid and cholesterol metabolism in hyposulfatemic NaS1 null mice
Authors: Dawson Paul Anthony , Gardiner Brooke , Grimmond Sean , Markovich Daniel
Published: April 2006

Sulfate plays an essential role in human growth and development, and its circulating levels are maintained by the renal Na+-SO42−cotransporter, NaS1. We previously generated a NaS1 knockout ( Nas1−/−) mouse, an animal model for hyposulfatemia, that exhibits reduced growth and liver abnormalities including hepatomegaly. In this study, we investigated the hepatic gene expression profile of Nas1−/−mice using oligonucleotide microarrays. The mRNA expression levels of 92 genes with known functional roles in metabolism, cell signaling, cell defense, immune response, cell structure, transcription, or protein synthesis were increased ( n = 51) or decreased ( n = 41) in Nas1−/−mice when compared with Nas1+/+mice. The most upregulated transcript levels in Nas1−/−mice were found for the sulfotransferase genes, Sult3a1 (≈500% increase) and Sult2a2 (100% increase), whereas the metallothionein-1 gene, Mt1, was among the most downregulated genes (70% decrease). Several genes involved in lipid and cholesterol metabolism, including Scd1, Acly, Gpam, Elov16, Acsl5, Mvd, Insig1, and Apoa4, were found to be upregulated (≥30% increase) in Nas1−/−mice. In addition, Nas1−/−mice exhibited increased levels of hepatic lipid (≈16% increase), serum cholesterol (≈20% increase), and low-density lipoprotein (≈100% increase) and reduced hepatic glycogen (≈50% decrease) levels. In conclusion, these data suggest an altered lipid and cholesterol metabolism in the hyposulfatemic Nas1−/−mouse and provide new insights into the metabolic state of the liver in Nas1−/−mice.
Challenging the Atheoretical Production of Nursing Knowledge: A Response to Reed and Rolfe’s Column
Authors: Mitchell Gail J. , Bournes Debra A.
Published: April 2006

This column is a response to Reed and Rolfe’s column in the January 2006 issue of Nursing Science Quarterly. The authors present their views about Reed and Rolfe’s ideas by focusing their discussion and questions on three main topics: the impact of nurses’ conceptual thinking, values, and culture on their perspectives and experiences; the reality that nursing theory-guided practice is already a meaningful reality in nursing; and the belief that in order not to limit knowledge development, science must be viewed as more than a study of proximal causes.
Cognitive, emotional, and quality of life outcomes in patients with pulmonary arterial hypertension
Authors: White Joanne , Hopkins Ramona O , Glissmeyer Eric W , Kitterman Natalie , Elliott C Gregory
Published: April 2006

Background

The effects of pulmonary arterial hypertension on cardiovascular and physical function are well documented. Limited information exists regarding the effects of pulmonary arterial hypertension on cognitive function despite patient reports of problems with memory and attention. Our primary purpose was to determine if a prospectively identified cohort of pulmonary arterial hypertension patients had cognitive sequelae. Our secondary purpose was to determine the relationships between cognitive sequelae and neuropsychological test scores with depression, anxiety, and quality of life.

Methods

Forty-six adults with pulmonary arterial hypertension underwent assessment of cognitive function, depression, anxiety, and quality of life using standardized neuropsychological tests and questionnaires. The patients' scores were compared to normal population data. Medical, affective, neuropsychological, and quality of life data for patients with and without cognitive sequelae were compared using analysis of variance, Chi-square, or Fisher exact tests for categorical data. Correlations assessed relationships between neuropsychological test scores, depression, anxiety, quality of life, and medical data.

Results

Cognitive sequelae occurred in 58% (27/46) of the pulmonary arterial hypertension patients. Patients with cognitive sequelae had worse verbal learning, delayed verbal memory, executive function, and fine motor scores compared to patients without cognitive sequelae. Twenty-six percent of patients had moderate to severe depression and 19% had moderate to severe anxiety. Depression, anxiety and quality of life were not different for patients with or without cognitive sequelae. Our patients had decreased quality of life, which was associated with worse working memory.

Conclusion

Patients with pulmonary arterial hypertension have cognitive impairments, depression, anxiety, and decreased quality of life. Depression, anxiety, and quality of life were similar for patients with cognitive sequelae compared to those without cognitive sequelae. Decreased quality of life was associated with worse verbal and working memory. Clinicians should be aware of adverse brain related outcomes in PAH patients. Attention to proximal determinants and possible interventions to prevent or reduce cognitive and emotional morbidity and decreased quality of life are warranted and should be an emphasis in outcomes research.
Latent Tuberculosis in HIV positive, diagnosed by the M. Tuberculosis Specific Interferon-γ test
Authors: Brock Inger , Ruhwald Morten , Lundgren Bettina , Westh Henrik , Mathiesen Lars R , Ravn Pernille
Published: April 2006

Background

Although tuberculosis (TB) is a minor problem in Denmark, severe and complicated cases occur in HIV positive. Since the new M. tuberculosis specific test for latent TB, the QuantiFERON-TB In-Tube test (QFT-IT) became available the patients in our clinic have been screened for the presence of latent TB using the QFT-IT test. We here report the results from the first patients screened.

Methods

On a routine basis the QFT-IT test was performed and the results from 590 HIV positive individuals consecutively tested are presented here. CD4 cell count and TB risk-factors were recorded from patient files.

Main findings

27/590(4.6%) of the individuals were QFT-IT test positive, indicating the presence of latent TB infection. Among QFT-IT positive patients, 78% had risk factors such as long-term residency in a TB high endemic area (OR:5.7), known TB exposure (OR:4.9) or previous TB disease (OR:4.9). The prevalence of latent TB in these groups were 13%, 16% and 19% respectively. There was a strong correlation between low CD4 T-cell count and a low mitogen response (P < 0.001;Spearman) and more patients with low CD4 cell count had indeterminate results.

Conclusion

We found an overall prevalence of latent TB infection of 4.6% among the HIV positive individuals and a much higher prevalence of latent infection among those with a history of exposure (16%) and long term residency in a high endemic country (13%). The QFT-IT test may indeed be a useful test for HIV positive individuals, but in severely immunocompromised, the test may be impaired by T-cell anergy.
Interleukin-10 haplotypes in Celiac Disease in the Spanish population
Authors: Núñez Concepción , Alecsandru Diana , Varadé Jezabel , Polanco Isabel , Maluenda Carlos , Fernández-Arquero Miguel , de la Concha Emilio G , Urcelay Elena , Martínez Alfonso
Published: April 2006

Background

Celiac disease (CD) is a chronic disorder characterized by a pathological inflammatory response after exposure to gluten in genetically susceptible individuals. The HLA complex accounts for less than half of the genetic component of the disease, and additional genes must be implicated. Interleukin-10 (IL-10) is an important regulator of mucosal immunity, and several reports have described alterations of IL-10 levels in celiac patients. TheIL-10gene is located on chromosome 1, and its promoter carries several single nucleotide polymorphisms (SNPs) and microsatellites which have been associated to production levels. Our aim was to study the role of those polymorphisms in susceptibility to CD in our population.

Methods

A case-control and a familial study were performed. Positions -1082, -819 and -592 of theIL-10promoter were typed by TaqMan and allele specific PCR. IL10R and IL10G microsatellites were amplified with labelled primers, and they were subsequently run on an automatic sequencer. In this study 446 patients and 573 controls were included, all of them white Spaniards. Extended haplotypes encompassing microsatellites and SNPs were obtained in families and estimated in controls by the Expectation-Maximization algorithm.

Results

No significant associations after Bonferroni correction were observed in the SNPs or any of the microsatellites. Stratification by HLA-DQ2 (DQA1*0501-DQB1*02) status did not alter the results. When extended haplotypes were analyzed, no differences were apparent either.

Conclusion

TheIL-10polymorphisms studied are not associated with celiac disease. Our data suggest that the IL-10 alteration seen in patients may be more consequence than cause of the disease.
Primary irritant and delayed-contact hypersensitivity reactions to the freshwater cyanobacterium Cylindrospermopsis raciborskii and its associated toxin cylindrospermopsin
Authors: Stewart Ian , Seawright Alan A , Schluter Philip J , Shaw Glen R
Published: April 2006

Background

Freshwater cyanobacteria are common inhabitants of recreational waterbodies throughout the world; some cyanobacteria can dominate the phytoplankton and form blooms, many of which are toxic. Numerous reports in the literature describe pruritic skin rashes after recreational or occupational exposure to cyanobacteria, but there has been little research conducted on the cutaneous effects of cyanobacteria. Using the mouse ear swelling test (MEST), we sought to determine whether three toxin-producing cyanobacteria isolates and the purified cyanotoxin cylindrospermopsin produced delayed-contact hypersensitivity reactions.

Methods

Between 8 and 10 female Balb/c mice in each experiment had test material applied to depilated abdominal skin during the induction phase and 10 or 11 control mice had vehicle only applied to abdominal skin. For challenge (day 10) and rechallenge (day 17), test material was applied to a randomly-allocated test ear; vehicle was applied to the other ear as a control. Ear thickness in anaesthetised mice was measured with a micrometer gauge at 24 and 48 hours after challenge and rechallenge. Ear swelling greater than 20% in one or more test mice is considered a positive response. Histopathology examination of ear tissues was conducted by independent examiners.

Results

Purified cylindrospermopsin (2 of 9 test mice vs. 0 of 5 control mice; p = 0.51) and the cylindrospermopsin-producing cyanobacterium C. raciborskii (8 of 10 test mice vs. 0 of 10 control mice; p = 0.001) were both shown to produce hypersensitivity reactions. Irritant reactions were seen on abdominal skin at induction. Two other toxic cyanobacteria (Microcystis aeruginosa and Anabaena circinalis) did not generate any responses using this model. Histopathology examinations to determine positive and negative reactions in ear tissues showed excellent agreement beyond chance between both examiners (κ = 0.83).

Conclusion

The irritant properties and cutaneous sensitising potential of cylindrospermopsin indicate that these toxicological endpoints should be considered by public health advisors and reservoir managers when setting guidelines for recreational exposure to cyanobacteria.
Identification of contrastive and comparable school neighborhoods for childhood obesity and physical activity research
Authors: Zhang Xingyou , Christoffel Katherine Kaufer , Mason Maryann , Liu Lin
Published: April 2006

The neighborhood social and physical environments are considered significant factors contributing to children's inactive lifestyles, poor eating habits, and high levels of childhood obesity. Understanding of neighborhood environmental profiles is needed to facilitate community-based research and the development and implementation of community prevention and intervention programs. We sought to identify contrastive and comparable districts for childhood obesity and physical activity research studies.

We have applied GIS technology to manipulate multiple data sources to generate objective and quantitative measures of school neighborhood-level characteristics for school-based studies. GIS technology integrated data from multiple sources (land use, traffic, crime, and census tract) and available social and built environment indicators theorized to be associated with childhood obesity and physical activity. We used network analysis and geoprocessing tools within a GIS environment to integrate these data and to generate objective social and physical environment measures for school districts. We applied hierarchical cluster analysis to categorize school district groups according to their neighborhood characteristics. We tested the utility of the area characterizations by using them to select comparable and contrastive schools for two specific studies.

Results

We generated school neighborhood-level social and built environment indicators for all 412 Chicago public elementary school districts. The combination of GIS and cluster analysis allowed us to identify eight school neighborhoods that were contrastive and comparable on parameters of interest (land use and safety) for a childhood obesity and physical activity study.

Conclusion

The combination of GIS and cluster analysis makes it possible to objectively characterize urban neighborhoods and to select comparable and/or contrasting neighborhoods for community-based health studies.
Moderate Hypoxia Influences Excitability and Blocks Dendrotoxin Sensitive K+ Currents in Rat Primary Sensory Neurones
Authors: Gruss Marco , Ettorre Giovanni , Stehr Annette Jana , Henrich Michael , Hempelmann Gunter , Scholz Andreas
Published: April 2006

Hypoxia alters neuronal function and can lead to neuronal injury or death especially in the central nervous system. But little is known about the effects of hypoxia in neurones of the peripheral nervous system (PNS), which survive longer hypoxic periods. Additionally, people have experienced unpleasant sensations during ischemia which are dedicated to changes in conduction properties or changes in excitability in the PNS. However, the underlying ionic conductances in dorsal root ganglion (DRG) neurones have not been investigated in detail.

Therefore we investigated the influence of moderate hypoxia (27.0 ± 1.5 mmHg) on action potentials, excitability and ionic conductances of small neurones in a slice preparation of DRGs of young rats. The neurones responded within a few minutes non-uniformly to moderate hypoxia: changes of excitability could be assigned to decreased outward currents in most of the neurones (77%) whereas a smaller group (23%) displayed increased outward currents in Ringer solution. We were able to attribute most of the reduction in outward-current to a voltage-gated K+ current which activated at potentials positive to −50 mV and was sensitive to 50 nM α-dendrotoxin (DTX). Other toxins that inhibit subtypes of voltage gated K+ channels, such as margatoxin (MgTX), dendrotoxin-K (DTX-K), r-tityustoxin Kα (TsTX-K) and r-agitoxin (AgTX-2) failed to prevent the hypoxia induced reduction. Therefore we could not assign the hypoxia sensitive K+ current to one homomeric KV channel type in sensory neurones. Functionally this K+ current blockade might underlie the increased action potential (AP) duration in these neurones. Altogether these results, might explain the functional impairment of peripheral neurones under moderate hypoxia.
Prolactin Deficiency Is Independently Associated with Reduced Insulin-Like Growth Factor I Status in Severely Growth Hormone-Deficient Adults
Authors: Mukherjee A. , Ryder W. D. J. , Jöstel A. , Shalet S. M.
Published: April 2006

Background: In adult life, considerable overlap in IGF-I status exists between normal and severely GH-deficient (GHD) subjects defined by conventional dynamic testing of GH secretion. IGF-I is not therefore widely viewed as a reliable diagnostic marker for GHD. Recognized factors influencing serum IGF-I level in GHD include age, gender, timing of onset of GHD, and exogenous estrogen therapy, but these do not fully explain GH/IGF-I discordance in severe GHD. The primary structures of prolactin and GH are closely related. Effects of hypoprolactinemia are not well described in humans, but laboratory studies suggest a role for prolactin in hepatic IGF-I release, possibly through a signal transducer and activator of transcription 5 (STAT5) pathway. The purpose of this study was to evaluate a potential contribution of prolactin to IGF-I status in severely GHD adults.

Patients and Methods: Using multiple regression analysis techniques, contributions of the following variables to age-adjusted IGF-I sd scores were evaluated in 162 (85 female) GHD adults: gender, timing of onset of GHD, presence or absence of prolactin deficiency, body mass index, number of additional pituitary deficits, and underlying pathology.

Results: Childhood onset GHD (P < 0.0001) and presence of prolactin deficiency (P < 0.0001) were independently associated with reduced IGF-I status. The contributions of these parameters to IGF-I sd scores were −2.55 and −2.67, respectively. Gender (P = 0.06), body mass index (P = 0.99), number of additional pituitary deficits (P = 0.64), and underlying pathology (P = 0.06) did not significantly influence IGF-I status.

Conclusions: Prolactin deficiency is independently associated with reduced IGF-I status in hypopituitary adults. It is possible that prolactin deficiency is a surrogate for the degree of severity of GHD, implying a GHD paradigm undetected by conventional GH provocative tests; alternatively, it remains plausible that circulating prolactin contributes to IGF-I release in the absence of GH, possibly through a signal transducer and activator of transcription 5 (STAT5) pathway.
Inefficient reprogramming of the hematopoietic stem cell genome following nuclear transfer
Authors: Inoue Kimiko , Ogonuki Narumi , Miki Hiromi , Hirose Michiko , Noda Shinichi , Kim Jin-Moon , Aoki Fugaku , Miyoshi Hiroyuki , Ogura Atsuo
Published: April 2006

In general, cloning undifferentiated preimplantation embryos (blastomeres) or embryonic stem cells is more efficient than cloning differentiated somatic cells. Therefore, there has been an assumption that tissue-specific stem cells might serve as efficient donors for nuclear transfer because of the undifferentiated state of their genome. Here, we show that this is not the case with adult hematopoietic stem cells (HSCs). Although we have demonstrated for the first time that mouse HSCs can be cloned to generate offspring, the birth rates (0-0.7%) were lowest among the clones tested (cumulus, immature Sertoli and fibroblast cells). Only 6% of reconstructed embryos reached the morula or blastocyst stage in vitro (versus 46% for cumulus clones; P<5×10-10). Transcription and gene expression analyses of HSC clone embryos revealed that they initiated zygotic gene activation (ZGA) at the appropriate timing, but failed to activate five out of six important embryonic genes examined, including Hdac1 (encoding histone deacetylase 1), a key regulator of subsequent ZGA. These results suggest that the HSC genome has less plasticity than we imagined, at least in terms of reprogrammability in the ooplasm after nuclear transfer.
Rac1 signalling in theDrosophilalarval cellular immune response
Authors: Williams Michael J. , Wiklund Magda-Lena , Wikman Shandy , Hultmark Dan
Published: April 2006

The Drosophila larval cellular immune response involves cells (hemocytes) that can be recruited from a hematopoietic organ located behind the brain, as well as a sessile population of cells found just underneath the larval cuticle arranged in a segmental pattern. By using two Rac1 GTPase effector-loop mutants together with epistasis studies, we show that Rac1 requires the Drosophila melanogaster Jun N-terminal kinase Basket (Bsk), as well as stable actin formation to recruit the sessile hemocyte population. We show that actin stabilization is necessary for Rac1-induced hemocyte activation by lowering cofilin (encoded by the twinstar gene tsr) expression in blood cells. Removing Bsk by RNAi suppressed Rac1-induced release of sessile hemocytes. RNAi against Bsk also suppressed Rac1 induction of lamellocytes, a specialized population of hemocytes necessary for the encapsulation of invading pathogens. Furthermore, Rac1 and Bsk are involved in regulating the formation of actin- and focal adhesion kinase (FAK)-rich placodes in hemocytes. Lastly, Rac1 and Bsk are both required for the proper encapsulation of eggs from the parasitoid wasp Leptipolina boulardi. From these data we conclude that Rac1 induces Bsk activity and stable actin formation for cellular immune activation, leading to sessile hemocyte release and an increase in the number of circulating hemocytes.
Enhanced Peroxidase Activity of Cytochrome c by Phosphate Bilayer Membrane
Authors: Fujita Akio , Senzu Hiroyuki , Kunitake Toyoki , Hamachi Itaru
Published: April 2006

Peroxidase activity of cytochrome c (cyt-c) as measured by oxidation of o-methoxyphenol with H2O2, was enhanced due to binding of cyt-c to a phosphate bilayer membrane. The rate enhancement and the membrane binding were not observed with ammonium and zwitterionic bilayer membranes.
Spectral Characteristics and Molecular Orientation of Azobenzene-Containing Hydrogen-Bond-Mediated Bilayer Membranes
Authors: Kimizuka Nobuo , Kawasaki Takayoshi , Kunitake Toyoki
Published: April 2006

Amphiphilic complexes of complementary hydrogen bond pairs containing an azobenzene chromophore formed bilayer membranes in water. The component orientation and thermal stability of the bilayer were examined by absorption and ICD spectral characteristics of the azobenzene chromophore.
Oxidations of Dihydroxyalkanoates to Vicinal Tricarbonyl Compounds with a 4-BzoTEMPO-Sodium Bromite System or by Indirect Electrolysis Using 4-BzoTEMPO and Bromide Ion
Authors: Inokuchi Tsutomu , Liu Ping , Torii Sigeru
Published: April 2006

An efficient access to vicinal dioxoalkanoates, one of structural elements of potent competitive inhibitors of hydrolytic enzyme, from 2,3-dihydroxyalkanoates has been developed, which features an one-step procedure with a mild oxidizing system using recyclable 2,2,6,6-tetramethylpiperidine-1-oxyl in combination with NaBrO2·3H2O or electrogenerated active bromine species as a real oxidant.
Photocatalytic Reduction of CO2 with Dispersed TiO2/Cu Powder Mixtures in Supercritical CO2
Authors: Mizuno Takayuki , Tsutsumi Hozumi , Ohta Kiyohisa , Saji Akira , Noda Hidetomo
Published: April 2006

CO2 was photocatalytically reduced to formic acid and methanol in supercritical CO2 using TiO2 and metal copper suspensions in the presence of water as hole scavengers. Copper particules covered by oxides films were more active in CO2 than TiO2.
Electrochemical Removal of NO and CH4 from Oxidizing Atmosphere
Authors: Hibino Takashi
Published: April 2006

An electrochemical cell, Pd | YSZ | Pd, was constructed to remove both NO and CH4 from an oxidizing atmosphere. When the direct current was supplied to the cell at 700 °C in the reactant flow containing 1000 ppm NO, 1000 ppm CH4 and an excess amount of O2, NO was reduced to N2 at the cathode, and CH4 was oxidized to COx at the anode.
Biofuels for Transport in the Uk: What is Feasible?: Review/Commentary Article
Authors: Jonathan  , Scurlock M.O.
Published: April 2006

Recent claims about the potential of UK land to support significant biofuels production for transport are bold, if not surprising. British renewable energy policy appears to be focussed on electricity production, at the expense of the heat and transport sectors. However there are environmental and strategic reasons for reducing the carbon intensity of UK road transport. This paper reviews past and recent studies of the feasibility of liquid biofuels production in Britain. Many earlier studies may have underestimated this potential, and the policy context has shifted significantly, but it would still be difficult to meet current UK gasoline needs from arable and set-aside land. In conclusion, a realistic short-term goal may be 2–3% of UK transport fuel needs from domestic resources by 2010.
Discussions on Climate Change as Presented in Nature, 2004
Authors: Barrett Jack
Published: April 2006

This article is a discussion of the issues surrounding the prediction of future climate and the difficulties of transmitting the science to the policy makers. The sources of information are restricted to the papers in Nature during the year 2004.
Amygdala and Ventromedial Prefrontal Cortex Are Inversely Coupled during Regulation of Negative Affect and Predict the Diurnal Pattern of Cortisol Secretion among Older Adults
Authors: Urry Heather L. , van Reekum Carien M. , Johnstone Tom , Kalin Ned H. , Thurow Marchell E. , Schaefer Hillary S. , Jackson Cory A. , Frye Corrina J. , Greischar Lawrence L. , Alexander Andrew L. , Davidson Richard J.
Published: April 2006

Among younger adults, the ability to willfully regulate negative affect, enabling effective responses to stressful experiences, engages regions of prefrontal cortex (PFC) and the amygdala. Because regions of PFC and the amygdala are known to influence the hypothalamic-pituitary-adrenal axis, here we test whether PFC and amygdala responses during emotion regulation predict the diurnal pattern of salivary cortisol secretion. We also test whether PFC and amygdala regions are engaged during emotion regulation in older (62- to 64-year-old) rather than younger individuals. We measured brain activity using functional magnetic resonance imaging as participants regulated (increased or decreased) their affective responses or attended to negative picture stimuli. We also collected saliva samples for 1 week at home for cortisol assay. Consistent with previous work in younger samples, increasing negative affect resulted in ventral lateral, dorsolateral, and dorsomedial regions of PFC and amygdala activation. In contrast to previous work, decreasing negative affect did not produce the predicted robust pattern of higher PFC and lower amygdala activation. Individuals demonstrating the predicted effect (decrease < attend in the amygdala), however, exhibited higher signal in ventromedial prefrontal cortex (VMPFC) for the same contrast. Furthermore, participants displaying higher VMPFC and lower amygdala signal when decreasing compared with the attention control condition evidenced steeper, more normative declines in cortisol over the course of the day. Individual differences yielded the predicted link between brain function while reducing negative affect in the laboratory and diurnal regulation of endocrine activity in the home environment.
Compartment-Dependent Colocalization of Kir3.2-Containing K+Channels and GABABReceptors in Hippocampal Pyramidal Cells
Authors: Kulik Ákos , Vida Imre , Fukazawa Yugo , Guetg Nicole , Kasugai Yu , Marker Cheryl L. , Rigato Franck , Bettler Bernhard , Wickman Kevin , Frotscher Michael , Shigemoto Ryuichi
Published: April 2006

G-protein-coupled inwardly rectifying K+channels (Kir3 channels) coupled to metabotropic GABABreceptors are essential for the control of neuronal excitation. To determine the distribution of Kir3 channels and their spatial relationship to GABABreceptors on hippocampal pyramidal cells, we used a high-resolution immunocytochemical approach. Immunoreactivity for the Kir3.2 subunit was most abundant postsynaptically and localized to the extrasynaptic plasma membrane of dendritic shafts and spines of principal cells. Quantitative analysis of immunogold particles for Kir3.2 revealed an enrichment of the protein around putative glutamatergic synapses on dendritic spines, similar to that of GABAB1. Consistent with this observation, a high degree of coclustering of Kir3.2 and GABAB1was revealed around excitatory synapses by the highly sensitive SDS-digested freeze–fracture replica immunolabeling. In contrast, in dendritic shafts receptors and channels were found to be mainly segregated. These results suggest that Kir3.2-containing K+channels on dendritic spines preferentially mediate the effect of GABA, whereas channels on dendritic shafts are likely to be activated by other neurotransmitters as well. Thus, Kir3 channels, localized to different subcellular compartments of hippocampal principal cells, appear to be differentially involved in synaptic integration in pyramidal cell dendrites.
A Spin Glass Model of Path Integration in Rat Medial Entorhinal Cortex
Authors: Fuhs Mark C. , Touretzky David S.
Published: April 2006

Electrophysiological recording studies in the dorsocaudal region of medial entorhinal cortex (dMEC) of the rat reveal cells whose spatial firing fields show a remarkably regular hexagonal grid pattern (Fyhn et al., 2004; Hafting et al., 2005). We describe a symmetric, locally connected neural network, or spin glass model, that spontaneously produces a hexagonal grid of activity bumps on a two-dimensional sheet of units. The spatial firing fields of the simulated cells closely resemble those of dMEC cells. A collection of grids with different scales and/or orientations forms a basis set for encoding position. Simulations show that the animal’s location can easily be determined from the population activity pattern. Introducing an asymmetry in the model allows the activity bumps to be shifted in any direction, at a rate proportional to velocity, to achieve path integration. Furthermore, information about the structure of the environment can be superimposed on the spatial position signal by modulation of the bump activity levels without significantly interfering with the hexagonal periodicity of firing fields. Our results support the conjecture of Hafting et al. (2005) that an attractor network in dMEC may be the source of path integration information afferent to hippocampus.
Prostaglandin D2-Mediated Microglia/Astrocyte Interaction Enhances Astrogliosis and Demyelination intwitcher
Authors: Mohri Ikuko , Taniike Masako , Taniguchi Hidetoshi , Kanekiyo Takahisa , Aritake Kosuke , Inui Takashi , Fukumoto Noriko , Eguchi Naomi , Kushi Atsuko , Sasai Hitoshi , Kanaoka Yoshihide , Ozono Keiichi , Narumiya Shuh , Suzuki Kinuko , Urade Yoshihiro
Published: April 2006

Prostaglandin (PG) D2is well known as a mediator of inflammation. Hematopoietic PGD synthase (HPGDS) is responsible for the production of PGD2involved in inflammatory responses. Microglial activation and astrogliosis are commonly observed during neuroinflammation, including that which occurs during demyelination. Using the genetic demyelination mousetwitcher, a model of human Krabbe’s disease, we discovered that activated microglia expressed HPGDS and activated astrocytes expressed the DP1receptor for PGD2in the brain of these mice. Cultured microglia actively produced PGD2by the action of HPGDS. Cultured astrocytes expressed two types of PGD2receptor, DP1and DP2, and showed enhanced GFAP production after stimulation of either receptor with its respective agonist. These results suggest that PGD2plays an important role in microglia/astrocyte interaction. We demonstrated that the blockade of the HPGDS/PGD2/DP signaling pathway using HPGDS- or DP1-nulltwitchermice, andtwitchermice treated with an HPGDS inhibitor, HQL-79 (4-benzhydryloxy-1-[3-(1H-tetrazol-5-yl)-propyl]piperidine), resulted in remarkable suppression of astrogliosis and demyelination, as well as a reduction in twitching and spasticity. Furthermore, we found that the degree of oligodendroglial apoptosis was also reduced in HPGDS-null and HQL-79-treatedtwitchermice. These results suggest that PGD2is the key neuroinflammatory molecule that heightens the pathological response to demyelination intwitchermice.
Pimarane Diterpenes and a Sesquiterpene from Salzmmania nitida
Authors: Carvalho Mário G. de , Alves Josinete S. , da-Cunha Emidio V. Leitão , Barbosa-Filho José M. , Silva Marcelo S. da
Published: April 2006

Two new terpenoids, (+)-3-oxo-thermarol and 11-acetoxyeudesman-4alpha-methyl-5alpha-ol along with the (+)- thermarol were isolated from the aerial parts of Salzmmania nitida. The structures and unambiguous ¹H and 13C chemical shift assignments were established by spectroscopic means, including homo and heteronuclear techniques.
Molecular basis of mammalian cell invasion by Trypanosoma cruzi
Authors: Yoshida Nobuko
Published: April 2006

Establishment of infection by Trypanosoma cruzi, the agent of Chagas' disease, depends on a series of events involving interactions of diverse parasite molecules with host components. Here we focus on the mechanisms of target cell invasion by metacyclic trypomastigotes (MT) and mammalian tissue culture trypomastigotes (TCT). During MT or TCT internalization, signal transduction pathways are activated both in the parasite and the target cell, leading to Ca2+ mobilization. For cell adhesion, MT engage surface glycoproteins, such as gp82 and gp35/50, which are Ca2+ signal-inducing molecules. In T. cruzi isolates that enter host cells in gp82-mediated manner, parasite protein tyrosine kinase as well as phospholipase C are activated, and Ca2+ is released from I P3-sensitive stores, whereas in T. cruzi isolates that attach to target cells mainly through gp35/50, the signaling pathway involving adenylate cyclase appears to be stimulated, with Ca2+ release from acidocalciosomes. In addition, T. cruzi isolate-dependent inhibitory signals, mediated by MT-specific gp90, may be triggered both in the host cell and the parasite. The repertoire of TCT molecules implicated in cell invasion includes surface glycoproteins of gp85 family, with members containing binding sites for laminin and cytokeratin 18, enzymes such as cruzipain, trans-sialidase, and an oligopeptidase B that generates a Ca2+-agonist from a precursor molecule.
Detecção do hipotireoidismo subclínico em gestantes com diferentes idades gestacionais
Authors: Andrade Luis J.O. , Cruz Thomaz , Daltro Carla , França Caroline S. , Nascimento Avelina O.S.
Published: April 2006

OBJETIVO: Detectar hipotireoidismo subclínico em gestantes. MATERIAL E MÉTODO: Foram estudadas 75 gestantes, voluntárias, residentes na cidade de Itabuna, Bahia. O protocolo constou de: critérios de inclusão: gestante com faixa etária < 40 anos, sem história prévia de doença tireoidiana ou auto-imunes e diabetes mellitus em qualquer idade gestacional; avaliação clínica com entrevista sob a forma de questionário; avaliação laboratorial com dosagem de T4 livre, TSH, anticorpos anti-TPO, perfil lipídico (colesterol total, HDL-colesterol e triglicérides); avaliação ultra-sonográfica da tireóide. RESULTADOS: A idade média foi de 21,6 ± 5,1 anos (14-40); a idade gestacional média foi de 24,2 ± 8,2 semanas (5-39); foi encontrado TSH elevado com T4 livre normal em 3 gestantes (4,0%). A positividade de anticorpos anti-TPO foi de 8,0%. Foram encontradas 5,4% de alterações ultra-sonográficas tireoidianas. CONCLUSÃO: Encontramos uma prevalência de 4,0% de hipotireoidismo subclínico na amostra, e com base neste resultado os autores consideram de grande importância a inclusão da avaliação tireoidiana na rotina do exame pré-natal. Estudos ulteriores se fazem necessários para estabelecer em que momento a avaliação tireoidiana de mulheres grávidas deve ser iniciada e com que freqüência deve ser repetida durante o curso da gestação.
Insuficiência renal crônica e hormônio de crescimento: efeitos no eixo GH-IGF e na leptina
Authors: Oliveira Josenilson C. de , Machado Neto Francisco de A. , Morcillo André Moreno , Oliveira Laurione C. de , Belangero Vera Maria S. , Geloneze Neto Bruno , Tambascia Marcos Antonio , Guerra-Júnior Gil
Published: April 2006

OBJETIVO: Avaliar as alterações de IGF-1, IGFBP-3, leptina e insulina após o uso de doses de reposição de hormônio de crescimento recombinante humano (rhGH) em crianças baixas pré-púberes com insuficiência renal crônica (IRC). CASUÍSTICA E MÉTODOS: Em 11 crianças (3F:8M), com idade média de 9,6 anos, em uso de rhGH (0,23mg/Kg/semana) por 12 meses, foram dosados (antes, 6 e 12 meses após o início do tratamento com rhGH) leptina, insulina, glicemia, IGF-1 e IGFBP-3. RESULTADOS: As concentrações séricas de leptina, insulina e glicemia não variaram significativamente no decorrer do uso do rhGH, sendo observado o padrão de leptina e glicemia normais, com hiperinsulinemia. Houve aumento significativo da IGF-1 e IGFBP-3 durante o uso do rhGH. CONCLUSÕES: O uso de doses de reposição de rhGH durante 12 meses em um grupo selecionado de crianças com IRC propiciou aumento significativo da concentração sérica de IGF-1 e IGFBP-3, com leptinemia normal e resistência insulínica.
Crescimento pós-menarca em uma coorte de meninas brasileiras
Authors: Castilho Silvia Diez , Saito Maria Ignez , Barros Filho Antonio de A.
Published: April 2006

Este trabalho teve como objetivo avaliar o crescimento pós-menarca em uma coorte de meninas brasileiras, e correlacioná-lo com a idade, estatura e IMC na menarca. Foram resgatados registros da idade, peso e estatura na menarca, e 5 anos após, de 111 meninas matriculadas na Unidade de Adolescentes do Instituto da Criança - HC - FMUSP. A mediana para a menarca foi 12,67 anos e a média de crescimento, 7,54 ± 3,35cm. Cresceram mais as que menstruaram mais cedo (r= -0,46; p= 0,0001) e as que eram mais baixas nesta ocasião (r= -0,44; p= 0,0001). Observou-se melhor correlação nas meninas com estatura entre p25 e p75 do referencial NCHS (r= -0,72; p= 0,0001). As adolescentes com maior IMC menstruaram mais cedo (11,9 anos). Não houve correlação entre o IMC e o crescimento (r= 0). Nesta coorte, o crescimento pós-menarca foi semelhante ao observado em outros estudos e as correlações fornecem informações para avaliar o potencial de crescimento por ocasião da menarca.
Estudo comparativo dos métodos coprológicos de Lutz, Kato-Katz e Faust modificado
Authors: Chaves Adelú , Alcantara Olinda Siqueira de , Carvalho Omar dos Santos , Santos José Soares dos
Published: April 2006

Foram estudados, comparativamente, em 500 pacientes, os métodos de exames de fezes de Lutz, Faust modificado e Kato-Katz para o diagnóstico parasitológico de fezes. O método de Kato-Katz proporcionou maiores índices de positividade do que as outras duas técnicas no diagnóstico de ancilostomideos, T. trichiurus e S. mansoni. Nenhuma diferença foi observada quanto ao diagnóstico de A. lumbricoides. Para o diagnóstico das protozooses não houve diferença significativa entre os métodos de Faust modificado e de Lutz. Baseado nos dados obtidos, eficiência, simplicidade e rapidez de execução recomenda-se a associação dos métodos de Kato-Katz e Faust modificado na rotina de diagnóstico parasitológico de fezes.
Reações clínicas à vacinação de adultos contra a rubéola
Authors: Candeias J. A. N. , Rácz M. L.
Published: April 2006

Descreve-se a incidência comparativa e as características das reações associadas à vacinação contra a rubéola de 305 mulheres adultas na faixa etária de 20 a 35 anos ou mais, com a vacina RA 27/3: 238 vacinações (77,8%) sem qualquer reação; 6 casos (1,9%) com febre, artralgias e adeno-patia retro-auricular; 8 casos (2,6%) com os mesmos sintomas anteriores e "rash" rubeliforme; 21 casos (6,9%) com adenopatia retro-auricular; mal estar geral sem sintomas respiratórios, 25 casos (8,2%) e com sintomas respiratórios das vias superiores, 8 casos (2,6).
Sensibilidade tuberculínica pós-vacinal e sua irrelevância para a revacinação BCG
Authors: Arantes Gilberto Ribeiro
Published: April 2006

Revisão realizada com o objetivo de mostrar que a prática de revacinar com BCG, baseada na negatividade do teste tuberculínico pós-vacinal, é destituída de fundamentos científicos. São apresentados alguns fatos nos quais se baseia o teste tuberculínico padronizado, seguidos de comentários sobre o perfil tuberculínico de populações não vacinadas. Considerações sobre o perfil tuberculínico de populações vacinadas e suas variações no indivíduo e no grupo vacinado como um todo, conduzem ao questionamento sobre uma possível correspondência entre alergia pós-vacinal e resistência à tuberculose. Fatos de natureza epidemiológica e dados experimentais são arrolados, mostrando que a proteção conferida pela vacina não é proporcional ao grau de alergia induzida nos indivíduos; a esses argumentos se acrescenta a recente demonstração de que, embora tuberculino-negativas, crianças vacinadas podem apresentar intensa reatividade linfocitária ao PPD. Discute-se a utilização do teste tuberculínico na avaliação do processo de vacinação.
Epidemiology and antimicrobial resistance of B. fragilis group organisms isolated from clinical specimen and human intestinal microbiota
Authors: Carvalho Cibele Barreto Mano de , Moreira José Luciano Bezerra , Ferreira Maria Candida S.
Published: April 2006

Epidemiological aspects and the antimicrobial susceptibility profile of the Bacteroides fragilis group isolated from clinical and human intestinal specimens were examined in this study. B. fragilis group strains were isolated from 46 (37%) of 124 clinical specimens and the source of the samples was: Blood culture (3), intraabdominal infection (27), brain abscess (2), soft tissue infection (17), respiratory sinus (3), pleural aspirate (9), breast abscess (3), surgical infected wound (22), pelvic inflammatory disease (22), chronic otitis media (9) and miscellaneous (7). Intraabdominal and soft tissue infections were responsible for more than half of the clinical isolates. Susceptibility to penicillin, cefoxitin, tetracycline, metronidazole, chloramphenicol and clindamycin was examined. All isolates were susceptible to metronidazole and chloramphenicol. For clindamycin and cefoxitin the resistance rates observed were 21.7% and 10.9% respectively. Susceptibility profiles varied among the different species tested. A total of 37 species of B. fragilis group isolated from intestinal microbiota of individuals who had no antimicrobial therapy for at least 1 month before the sampling was also examined. All strains were also susceptible to chloramphenicol and motronidazole and the resistance rates to clindamycin and cefoxitin were 19.4% and 5.4% respectively. A few institutions, in Brazil, have monitored the antimicrobial susceptibility of B. fragilis group strains isolated from anaerobic infections. The resistance rates to cefoxitin and clindamycin and the variation in susceptibility patterns among the species isolated in this study emphasize the need for monitoring of susceptibility patterns of B. fragilis group organisms isolated, especially at our University Hospitals.
Histoplasmin and paracoccidioidin skin reactivity in infantile population of Northern Argentina
Authors: Mangiaterra Magdalena , Alonso José , Galvan Miria , Giusiano Gustavo , Gorodner Jorge
Published: April 2006

In order to estimate ages at which etiological agents of systemic mycoses initiate infection, histoplasmin and paracoccidioidin skin tests were performed in 344 children of both sexes, between 2 and 15 years old. They were selected from a statistically significant population sample Gral. San Martín city (Northeast Argentina). Tests were read 48h after injection and considered positive if a 5 mm on larger induration was present. Circulating antibodies were also evaluated by agar gel immunodiffusion. The overall infection rate for H. capsulatum was 9.2%, belonging to children from 4 to 14 years old, without significant differences among sexes. Five children from 2 to 14 years old were positive to paracoccidioidin (1.6%). None of the children had specific antibodies neither signs of active mycosis. Results show H. capsulatum infection can be found from age 4, while for P. brasiliensis the lower limit was two years old. These findings may contribute to better knowledge on infantile fungal infection in a geographical region where no previous references can be found.
Seroepidemiology of human toxoplasmosis in Chile
Authors: Contreras Maria del C. , Schenone Hugo , Salinas Patricia , Sandoval Lea , Rojas Antonio , Villarroel Fernando , Solis Fresia
Published: April 2006

A series of already published and unpublished seroepidemiological surveys for toxoplasmosis, carried out in Chile in 1982-1994, is reviewed, expanded and analyzed. The surveys included 76,317 apparently healthy individuals of different ages (0.57% of the country's total population), from 309 urban and rural-periurban localities. Urban groups were integrated by blood donors, delivering mothers and middle grade schoolchildren, while rural-periurban individuals corresponded to unselected family groups. Blood samples were collected in filter paper. The presence of antibodies to Toxoplasma gondii was determined by the indirect hemagglutination test (IHAT), titers > 16 were considered positive. The test resulted positive in 28,124 (36.9%) of the surveyed people. Two hundred and six (0.3%) individuals presented IHAT titers > 1000, probably corresponding to acute or reactivated infections. A progressive increase of positive IHAT from northern to southern regions of the country was noted, phenomenom probably related to geographical conditions and to a higher production and consumption of different types of meat in the latter regions. It is postulated that ingestion of T. gondii cysts by humans is epidemiologically as important as ingestion of oocysts. The results presented stress the epidemiological importance of toxoplasmosis in humans, and warn about eventual implications in immunocompromised patients and in transplacental transmission, organ transplants and transfusions.
Adulticidal activity against Stegomyia aegypti (Diptera: Culicidae) of three Piper spp.
Authors: Choochote Wej , Chaithong Udom , Kamsuk Kittichai , Rattanachanpichai Eumporn , Jitpakdi Atchariya , Tippawangkosol Pongsri , Chaiyasit Dana , Champakaew Daruna , Tuetun Benjawan , Pitasawat Benjawan
Published: April 2006

Three Piper species, Piper longum, P. ribesoides and P. sarmentosum, were selected for investigation of adulticidal potential against Stegomyia aegypti, a main vector of dengue and dengue haemorrhagic fever. Successive extraction by maceration with 95% ethanol showed percentage yields of ethanolic extracts, which derived from P. longum, P. ribesoides and P. sarmentosum, of 8.89, 3.21 and 5.30% (w/w), respectively. All Piper extracts illustrated an impressive adulticidal activity when tested against female mosquitoes by topical application. The susceptibility of St. aegypti females to ethanol-extracted Piper was dose dependent and varied among the plant species. The highest adulticidal effect was established from P. sarmentosum, followed by P. ribesoides and P. longum, with LD50 values of 0.14, 0.15 and 0.26 µg/female, respectively. The potential of these Piper species, as possible mosquitocides, established convincing activity for further researches to develop natural substances for combat against adult mosquitoes.
Cystoscopy in the diagnosis and follow-up of urinary schistosomiasis in Brazilian soldiers returning from Mozambique, Africa
Authors: Silva Iran Mendonça da , Thiengo Roberto , Conceição Maria José , Rey Luis , Pereira Filho Edson , Ribeiro Paulo Cesar
Published: April 2006

The assessment of urinary schistosomiasis in individuals coming from endemic areas often requires diagnostic resources not used in areas of exposure in order to determine complications or to establish more precise criteria of cure. Cystoscopy and 24-hour urine examination were performed, after treatments with praziquantel 40 mg/kg body weight, single dose, on 25 Brazilian military men who were part of a United Nations peace mission to Mozambique in 1994. The median age of the individuals was 29 years and all presented a positive urine parasitological exam. The alterations detected by cystoscopy were hyperemia and granulomas in the vesical submucosa in 59.1% of the individuals and only granulomas in 40.9%. A vesical biopsy revealed granulomas in all patients and viable eggs in 77.3% even after a period during which the patients no longer excreted eggs in urine. Cystoscopy after treatment, followed by biopsy and histopathological evaluation, performed in areas where the evolution of the disease can be better monitored, was found to be a safe criterion of parasitological cure.