First Report of Tomato chlorosis virus in Tomato in Costa Rica.

In early 2007, severe yellowing and chlorosis symptoms were observed in field-grown and greenhouse tomato (Solanum lycopersicum L.) plants in Costa Rica. Symptoms resembled those of the genus Crinivirus (family Closteroviridae), and large populations of whiteflies, including the greenhouse whitefly Trialeurodes vaporariorum (Westwood), were observed in the fields and on symptomatic plants. Total RNA was extracted from silica gel-dried tomato leaf tissue of 47 representative samples (all were from symptomatic plants) using TRI Reagent (Molecular Research Inc., Cincinnati, OH). Reverse transcription (RT)-PCR reactions were performed separately with each of the four primer sets with the Titan One-Tube RT-PCR Kit (Roche Diagnostics Corp., Chicago IL). Specific primers used for the detection of the criniviruses, Tomato chlorosis virus (ToCV) and Tomato infectious chlorosis virus (TICV), were primer pair ToCV-p22-F (5'-ATGGATCTCACTGGTTGCTTGC-3') and ToCV-p22-R (5'-TTATATATCACTCCCAAAGAAA-3') specific for the p22 gene of ToCV RNA1 (1), primer pair ToCVCPmF (5'-TCTGGCAGTACCCGTTCGTGA-3') and ToCVCPmR (5'-TACCGGCAGTCGTCCCATACC-3') designed to be specific for the ToCV CPm gene of ToCV RNA2 (GenBank Accession No. AY903448) (2), primer pair ToCVHSP70F (5'-GGCGGTACTTTCGACACTTCTT-3') and ToCVHSP70R (5'-ATTAACGCGCAAAACCATCTG-3') designed to be specific for the Hsp70 gene of RNA2 of ToCV (GenBank Accession No. EU284744) (1), and primer pair TICV-CP-F and TICV-CP-R specific for the coat protein gene of TICV (1). Amplified DNA fragments (582 bp) were obtained from nine samples, four from the greenhouse and five from the open field, with the ToCV-p22 specific primers and were cloned into the pCRII TOPO cloning vector (Invitrogen, Carlsbad, CA). Nucleotide sequence analysis of all purified RT-PCR products verified their identity as ToCV, sharing 99.5 to 100% sequence identity among themselves and 96% to 98% sequence identity with previously reported ToCV p22 sequences from Florida (Accession No. AY903447), Spain (Accession No. DQ983480), and Greece (Accession No. EU284745). The presence of ToCV in the samples was confirmed by additional amplification and sequence analysis of the CPm (449-bp fragment) and Hsp70 (420-bp fragment) genes of ToCV RNA2 and sharing 98 to 99% sequence homology to Accession Nos. AY903448 and EU284774, respectively. One representative sequence of the p22 gene of the Costa Rican isolate was deposited at GenBank (Accession No. FJ809714). No PCR products were obtained using either the TICV-specific primers nor from healthy tomato tissue. The ToCV-positive samples were collected from a region in the Central Valley around Cartago, Costa Rica. To our knowledge, this is the first report of ToCV in Costa Rica. The economic impact on tomato has not yet been determined. Studies are underway to determine the incidence of ToCV in Costa Rica field-grown and greenhouse tomatoes. References: (1) A. R. A. Kataya et al. Plant Pathol. 57:819, 2008. (2) W. M. Wintermantel et al. Arch. Virol. 150:2287, 2005.

Acetylene Storage and Separation Using Metal-Organic Frameworks with Open Metal Sites.

Efficient separation and storage of gas streams involving light hydrocarbons is essential for industrial applications. These hydrocarbons are widely used as energy resources and/or chemical raw materials in various chemical reactions. Here, we focus on the separation of acetylene from methane and carbon dioxide. The separation of acetylene from carbon dioxide is, in particular, challenging due to the similar kinetic diameters and boiling points of the molecules. In recent years, considerable progress has been made in adsorption-based separations using porous metal-organic frameworks (MOFs). Most reported studies are experimental. We present a computational study on these gas separations using a variety of MOFs. This allows investigation of the competitive gas adsorption, which is experimentally challenging, as well as understanding the adsorption mechanisms at the molecular level, which in turn allows further experimental MOF design for this application. MOFs with open metal sites, and particularly Fe-MOF-74, seem to be good for this separation, with a trade-off between physical adsorption capacity and selectivity. Based on experimental single-adsorption isotherms at various temperatures, we developed and validated a specific parameterization to account for the interactions of the olefin with the open metal sites. In addition to volumetric and calorimetric adsorption, we comprehensively investigate the characteristics of the interaction between the MOFs and the guest molecules in terms of binding sites and density profiles. The overall agreement of our simulated results with experimental data for pure components points to the reliability of the models and methods to successfully predict the separation of mixtures.

Stream fish, water and habitat quality in a pasture dominated basin, southeastern Brazil.

A fish survey in 35 stream reaches (from 1st to 3rd order) with physicochemical and habitat assessment in the São José dos Dourados system, southeastern Brazil, was conducted. Most of the basin land cover (77.4%) is used for pasture. From the sampled stream reaches, 24 were of good physicochemical quality, 10 of fair quality, and only one of poor quality. A habitat assessment showed that 10 stream reaches were considered fair, 22 were poor, and 3 were very poor. Fifty species were collected and their abundances showed strong correlation with habitat descriptors. In addition to the correlation between fish abundance and habitat, some species also showed optimal distribution related to the degree of physical habitat conservation. Streams located in this region experience organic pollution, but the most important aspect is the decline of the instream physical habitat condition, especially in first order streams, which negatively affects coarse substrates and water column dependent fish species. Effluent control, riparian vegetation restoration programs, siltation control and adequate sustainable soil use are practices which could mitigate such impacts.

Brazilian pemphigus foliaceus autoantibodies are pathogenic to BALB/c mice by passive transfer.

Brazilian pemphigus foliaceus (fogo selvagem) is a cutaneous blistering disease endemic to certain areas of South America that has distinctive epidemiologic features suggestive of an infectious disease transmitted by an insect vector. Patients with the disease have antiepithelial autoantibodies, both circulating in the serum and bound to lesional epidermis. In order to examine the possible pathogenic role of these autoantibodies, IgG from the sera of these patients was purified and injected into the peritoneum of neonatal BALB/c mice. Thirty-four of 46 mice (74%) receiving parenteral IgG fractions from these patients developed cutaneous lesions that were identical to the human disease by clinical, histologic, immunologic, and ultrastructural criteria. High-titer Brazilian pemphigus foliaceus sera produced lesions more consistently and rapidly than low-titer sera. When injections were discontinued, new lesions ceased to appear and old lesions resolved. The extent of disease correlated with the titer of human antiepithelial antibodies detected in the mouse serum (z less than 0.01). Similar concentrations of IgG fractions obtained from sera of unaffected Brazilians living in endemic areas and from American donors did not induce disease when injected into littermates. These results establish that the antiepithelial autoantibodies play an important role in the pathogenesis of the cutaneous lesions in Brazilian pemphigus foliaceus.

Endemic pemphigus foliaceus (Fogo Selvagem): II. Current and historic epidemiologic studies.

This paper details current and historic epidemiologic features of Fogo Selvagem (Endemic pemphigus foliaceus) in Brazil. The following features are described. a) The disease occurs in endemic fashion in regions of Brazil within the states of Goias, Mato Grosso do Sul, Parana, Sao Paulo, and Minas Gerais. It appears that the disease is spreading toward the northwest and west, involving the states of Mato Grosso, Para, Maranhao, Rondonia, Acre, and Amazonas. b) People at risk are young peasants or children of either sex or any race exposed to the local ecology in rural areas of endemic states. Although the disease has been described in urban centers, these occurrences are rare. c) Fogo Selvagem commonly appears in wild areas being colonized and disappears as these areas become urbanized. d) The majority of patients live in close proximity to rivers and within the 10-15 Km flying range of mosquitos or black flies (such as Simulium). It is hypothesized that a black fly, Simulium pruinosum may be the vector that precipitates the disease. f) There is a significant number of Fogo Selvagem in family units where multiple, genetically related individuals are affected. g) Finally, autoantibodies against lupus-associated antigens are not present in the sera of patients with Fogo Selvagem. Clinical examination of the skin, and serologic screening for pemphigus autoantibodies are specific parameters that can be used in the search for the etiologic agents that lead to autoimmune disease of the skin. To identify and prove an etiologic agent for this well-characterized autoimmune disease would be of tremendous importance to the understanding of autoimmune skin diseases, and potentially other organ-specific autoimmune disorders.

Congenital scalp skull defects with distal limb anomalies (Adams-Oliver syndrome--McKusick 10030): further suggestion of autosomal recessive inheritance.

We describe a man with manifestations of the Adams-Oliver syndrome: congenital scalp defect with hypoplastic fingers and toes. The patient has normal first-cousin parents: among seven sibs, three sisters and two brothers are normal; two brothers born with the same scalp lesion died as a consequence of bleeding from this abnormal area. There is no evidence of other affected relatives. The family of our patient is suggestive of autosomal recessive inheritance of this disorder with phenotypic manifestations identical to those present in the autosomal dominant form. Dermatoglyphic findings are discussed.

Interaction of poly methyl vinyl ether/maleic anhydride-dimiristoyl phosphatidylcholine: a model bioadhesion study.

The objective of this work is to study the interaction of a copolymer, poly methyl vinyl ether/maleic anhydride (PMV/MA) used in pharmaceutical dosage form and a phospholipid L-alpha-dimiristoyl phosphatidylcholine (DMPC) with the aim of developing a bioadhesive system. Glycerine is the plastifiant used to make PMV/MA insoluble. We have studied copolymer-plastifiant compatibility with differential scanning calorimetry and we have studied the influence that the solvents produce on the copolymer by infrared spectroscopy. Monolayer experiments were carried out with a Wilhelmy-type surface balance. The purpose of these experiments is to obtain molecular information about interaction PMV/MA-glycerine system with DMPC. The results show that there are attractive forces and it is a spontaneous process.

Antagonism by citalopram and tianeptine of presynaptic 5-HT1B heteroreceptors inhibiting acetylcholine release.

The interactions of citalopram and tianeptine, two antidepressants having opposite effects on serotonin (5-HT) uptake, with 5-HT1B presynaptic heteroreceptors located on cholinergic terminals were investigated. In rat hippocampal synaptosomes, citalopram (0.01 or 0.1 microM) or tianeptine (0.01-10 microM) did not modify the basal or the K(+)-evoked release of [3H]acetylcholine. Only at the concentration of 100 microM did tianeptine significantly decrease (-18%) the K(+)-evoked release of [3H]acetylcholine without affecting the spontaneous outflow of radioactivity. The inhibitory effect of 7-trifluoromethyl-4-(4-1-piperazinyl)-pyrrolo[1,2-a]quinoxaline (CGS 12066B), a 5-HT1B receptor agonist, on the stimulation-induced release of [3H]acetylcholine was reduced in a concentration-dependent manner by citalopram and tianeptine. Both drugs completely reversed the inhibitory effects of CGS 12066B at concentrations that did not modify by themselves the release of [3H]acetylcholine. In contrast, tianeptine, up to a concentration of 1 microM, failed to antagonise the inhibitory effect of the muscarinic receptor agonist carbachol on K(+)-evoked [3H]acetylcholine release. Finally, the administration of tianeptine ex vivo (10 or 20 mg/kg) modified neither the depolarisation-induced release of [3H]acetylcholine nor the inhibitory effect of CGS 12066B on this presynaptic process. These findings further confirm that antidepressants interact in vitro with presynaptic 5-HT1B heteroreceptors.

Effects of stress on the functional properties of pre- and postsynaptic 5-HT1B receptors in the rat brain.

Numerous studies have clearly shown that the turnover and release of serotonin (5-hydroxytryptamine, 5-HT) are increased under acute stressful conditions. Inasmuch as this latter process is under the control of a feedback mechanism involving the stimulation of presynaptic 5-HT1B autoreceptors, we have investigated the possible effects of acute restraint (40 min) on the functional properties of 5-HT1B receptors. The efficacy of the selective 5-HT1B receptor agonist 3-[1,2,5,6-tetrahydropyrid-4-yl]pyrrolo-[3,2-b]pyrid-5-one (CP-93,129) in inhibiting in vitro the K+-evoked release of [3H]5-HT, was significantly reduced in stressed rats as compared to naive animals. Similarly, the responsiveness of 5-HT1B receptors inhibiting the release of [3H]acetylcholine (presynaptic 5-HT1B heteroreceptors), was reduced by restraint. These effects were observed in the hippocampus, but using the inhibitory effect of CP-93,129 on forskolin-stimulated adenylyl cyclase activity as an index of 5-HT1B receptor function, it could be shown that the 5-HT1B receptors located in the substantia nigra are also desensitized by stress. The number as well as the apparent affinity constant of 5-HT1B binding sites labelled by [125I]iodocyanopindolol, as measured by quantitative autoradiography and membrane binding, were similar in naive and restraint-stressed rats suggesting that the stress-induced desensitization of 5-HT1B receptors is not due to a reduced number of 5-HT1B binding sites. As stress is thought to be a causal factor for the etiology of anxiety and depression, these results support the potential involvement of 5-HT1B receptor dysfunction in the development of these neurological disorders.

Immunoblot analyses of Brazilian pemphigus foliaceus antigen using different antigen sources.

We investigated the Brazilian pemphigus foliaceus (BPf) antigen applying the immunoblotting method to two different antigen sources using 27 patients' sera. Twelve BPf sera reacted specifically with a 150 kD protein in extract of dispase separated human epidermis, while 18 sera yielded a similar protein band in bovine muzzle desmosomal preparation. The diversity of staining intensities between the two samples suggested the heterogeneity of BPf antigens in terms of epitopes. Japanese sporadic pemphigus foliaceus (Pf) sera showed similar results but Japanese pemphigus vulgaris (Pv) sera recognized different antigens of 130 kD or 135 kD, suggesting that BPf is similar to Japanese Pf but is distinct from Pv in respect to the antigenic substance. Furthermore, the present study showed that immunoblot analysis using different antigen sources should be a valuable tool to determine clinical types of pemphigus.

Insights into the physiological function of cellular prion protein.

Prions have been extensively studied since they represent a new class of infectious agents in which a protein, PrPsc (prion scrapie), appears to be the sole component of the infectious particle. They are responsible for transmissible spongiform encephalopathies, which affect both humans and animals. The mechanism of disease propagation is well understood and involves the interaction of PrPsc with its cellular isoform (PrPc) and subsequently abnormal structural conversion of the latter. PrPc is a glycoprotein anchored on the cell surface by a glycosylphosphatidylinositol moiety and expressed in most cell types but mainly in neurons. Prion diseases have been associated with the accumulation of the abnormally folded protein and its neurotoxic effects; however, it is not known if PrPc loss of function is an important component. New efforts are addressing this question and trying to characterize the physiological function of PrPc. At least four different mouse strains in which the PrP gene was ablated were generated and the results regarding their phenotype are controversial. Localization of PrPc on the cell membrane makes it a potential candidate for a ligand uptake, cell adhesion and recognition molecule or a membrane signaling molecule. Recent data have shown a potential role for PrPc in the metabolism of copper and moreover that this metal stimulates PrPc endocytosis. Our group has recently demonstrated that PrPc is a high affinity laminin ligand and that this interaction mediates neuronal cell adhesion and neurite extension and maintenance. Moreover, PrPc-caveolin-1 dependent coupling seems to trigger the tyrosine kinase Fyn activation. These data provide the first evidence for PrPc involvement in signal transduction.

Does dietary tryptophan play a role in the control of convulsive activity?

The convulsive response to pentylenetetrazol was investigated in rats receiving different dietary tryptophan inputs. In the first experiment the animals were fed either a corn or a corn-supplemented diet. In the second one they received either a control diet supplemented with tryptophan, a low-protein/high-carbohydrate diet, or a low-protein/high-carbohydrate tryptophan-supplemented diet. The control groups for both experiments were fed a diet containing 22% milk protein. The corn diet facilitated seizures; the low-protein/high-carbohydrate/tryptophan diet prevented seizures. These results suggest that the brain serotonin levels determined by dietary tryptophan, or tryptophan by itself, could play a role in the convulsive response.

Neonatal treatment with naloxone causes permanent hyperalgesia in rats.

The effect of treatment with naloxone early in life on pain responsiveness was studied in Wistar rats. Litters of six rats were divided equally into groups of 3 pups receiving daily naloxone (50 mg/kg, sc) and 3 pups receiving saline from the 3rd to 18th day of life. On days 30, 50, 70 and 90, one group of animals previously injected during suckling with naloxone (N = 21) and another with saline (N = 21) were submitted to the hot-plate test to measure the latency to paw licking. Other groups of rats also treated during suckling with naloxone (N = 13) and saline (N = 14) were assessed for the antinociceptive effect of morphine (10 mg/kg,sc). The naloxone group displayed a lower latency than the saline group in all test sessions and a diminished analgesic response to morphine. The results indicate that the use of naloxone (an antagonist opioid) during suckling, the brain growth spurt period, facilitates a long-lasting increased pain responsiveness and alters antialgesic mechanisms. In this respect, the opioid and non-opioid effects of naloxone on the ontogeny of neural systems should be taken into account.

Interaction of bovine myelin basic protein with triphosphoinositide.

Despite the essential role played by myelin basic protein (MBP) in stabilizing the multilamellar structure of the myelin membrane, attempts at deciphering the structure of MPB have so far failed. Given that MBP is known to specifically interact with the membrane's lipid components, this study was designed to explore the effects of these lipids on the conformation of the protein by examining its interaction with the lipid triphosphoinositide (TPI). MBP was identified by high-performance liquid chromatography (HPLC) in myelin extracted from cow's brain and its molecular weight determined. In aqueous solution, MBP showed a random coil structure confirmed by its circular dichroism (CD) spectra. Possible structural changes to the protein induced by different proportions of TPI were also explored. The CD spectra of these mixtures indicated that this lipid fails to induce the adoption of a secondary structure by MBP. We then performed monolayer experiments to evaluate the type of interaction that occurs between MBP and TPI. First, the molecular weight of the protein sample was established to determine the state of the MBP within the monolayer by applying the equation for gases to the so-called gaseous zone of the monolayer for the conditions under which the expression holds. The similar molecular weights yielded by HPLC performed on dissolved samples and by the monolayers suggests that, as in solution, in the membrane the protein exists as a monomer. Monolayer data suggest forces of attraction between the two components and, through thermodynamic calculations, it was established that this interaction is spontaneous and the interaction is of the electrostatic type.

[Indirect immunofluorescence in endemic pemphigus foliaceus. A contribution to its standardization]. / Imunofluorescência indireta no pênfigo foliáceo endêmico. Contribuição para sua padronização.

The aim of the present research was to standardize the indirect immunofluorescence reaction for Endemic Pemphigus Foliaceus (Fogo Selvagem). We found that fresh human skin was the ideal substrate and could proceed from foreskin, head, neck, or anterior abdominal wall. PBS pre-washing of the skin preceding the incubation with the serum should be avoided since the antigenicity might be diminished. TAS-calcium pre-serves the Pemphigus antigenic properties of the skin and shall be preferred as the diluent for the sera. Albumin-coated slides are useful because they increase the adherence of the skin sections. The conjugate appropriate dilution is convenientely determined by the radial immunodiffusion test (Ouchterlony method). So far as the correlation between the antibody titer and the clinical activity is concerned, we concluded that a titer of 160 or more was of bad prognosis, since it was associated with the generalized form of the disease or with cases of the localized form refractory to the usual therapy. Nevertheless, this assumption needs confirmation by further studies involving an appropriate clinical approach.

Action of selective serotonin reuptake inhibitor on aggressive behavior in adult rat submitted to the neonatal malnutrition.

The effect of the malnutrition during suckling on the aggressiveness was investigated in adult rats treated or not with citalopram, a selective serotonin reuptake inhibitor (SSRI). The animals were divided into two groups according to the diet used: nourished group - the rats received the control diet with 23% protein during the life; and malnourished group - the rats had its mothers submitted to diet with 7.8% protein during suckling. At 120 days of age, each group was sub-divided according to the treatment: acute - consisting a single i.p. injection of saline solution or 20-mg/Kg citalopram; chronic - consisting the single injections (1 per day during 14 days) of saline or 20 mg/Kg citalopram. The acute or chronic treatment with SSRI reduces aggressive response in nourished rats, but not in malnourished ones. Thus, the malnutrition during the critical period of brain development seems to induce durable alterations in the function of the serotoninergic neurotransmission

[Paracoccidioidomycosis. Accidental inoculation "in anima nobile." Report of a case]. / Paracoccidiomicose. Inoculacao acidental "in anima nobile". Relato de un caso

A case of paracoccidioidomycosis by accidental innoculation on the back of the left hand in a female patient is presented. Clinically the manifestation was of a hard and painful nodular lesion. This lesion was completely excised surgically. This lesion was completely excised surgically. The material obtained revealed the "Paracoccidioides brasillensis" by direct and histopathologic microscopic examinations. No culture was obtained. The histopathologic aspect of the lesion was of a tuberculoid granuloma. The immunological study demonstrated a positive intradermic test and negative results by complement fixation and preciptin reactions. The lesion cured completely after the surgical excision and sulfadimetoxin treatment.

[Annular granuloma in HIV-positive patient]. / Granuloma anular en paciente HIV-positivo.

The Authors present a HIV-positive patient with atypical lesions of Granuloma annulare near the joints. Ten HIV-positive patients with Granuloma annulare have been reported until now in the world literature, and these cases are reviewed.

Unlimited access to low-energy diet causes acute malnutrition in dams and alters biometric and biochemical parameters in offspring.

Here we analyze the outcomes of unlimited access to a low-energy (LE) diet in dams and their offspring. At 3 weeks' gestation, pregnant Wistar rats were divided into two groups: (1) the control group received a normoenergetic diet; and (2) the experimental group received the LE diet. In dams, lactation outcomes, food intake, body weight, plasma IGF-1, prealbumin, transferrin and retinol-binding protein levels were evaluated; in offspring, biometric and biochemical parameters and food intake were evaluated. No differences were observed during pregnancy. However, after lactation, dams that received the LE diet demonstrated significant reductions in body weight (P<0.05), plasma IGF-1 (P=0.01), prealbumin and visceral fat (P<0.001). Pups born to dams that received the LE diet demonstrated reduced body length and weight at weaning (P<0.001) and were lighter than the control animals at the end of the experimental period. Pups also demonstrated reduced plasma, low-density lipoprotein (P=0.04), triglycerides (P=0.002) and glucose levels (P<0.05), and differences were noted in visceral fat. These results indicate that feeding dams with LE diet during the reproductive period induces acute malnutrition and impairs the growth and development of offspring, as well as certain metabolic parameters.

Effects of maternal separation on the dietary preference and behavioral satiety sequence in rats.

This study investigated the effects of maternal separation on the feeding behavior of rats. A maternal separation model was used on postnatal day 1 (PND1), forming the following groups: in the maternal separation (MS) group, pups were separated from their mothers each day from PND1 to PND14, whereas in the control (C) group pups were kept with their mothers. Subgroups were formed to study the effects of light and darkness: control with dark and light exposure, female and male (CF and CM), and maternal separation with dark and light exposure, female and male (SDF, SDM, SLF and SLM). Female rats had higher caloric intake relative to body weight compared with male controls in the dark period only (CF=23.3±0.5 v. CM=18.2±0.7, P<0.001). Macronutrient feeding preferences were observed, with male rats exhibiting higher caloric intake from a protein diet as compared with female rats (CF=4.1±0.7, n=8 v. CM=7.0±0.5, n=8, P<0.05) and satiety development was not interrupted. Female rats had a higher adrenal weight as compared with male rats independently of experimental groups and exhibited a higher concentration of serum triglycerides (n=8, P<0.001). The study indicates possible phenotypic adjustments in the structure of feeding behavior promoted by maternal separation, especially in the dark cycle. The dissociation between the mother's presence and milk intake probably induces adjustments in feeding behavior during adulthood.