Dynamics of 45S rDNA sites in the cell cycle: fragile sites and chromosomal stability in Lolium and Festuca.

Analyses carried out with fluorescence in situ hybridization (FISH) in C-metaphases of the Lolium-Festuca complex have shown the occurrence of spontaneous fragile sites (FSs) in 45S rDNA regions. FSs are expressed as gaps but they do not result in breaks or chromosomal fragments in these species. These gaps have high DNA condensation observed as thin chromatin fibers that connect the apparent segments of the fragile chromosome, allowing for genomic stability. Assessing the behavior of these regions in the cell cycle of Lolium and Festuca species may lead to a better understanding of the dynamics that preserve stability during cell division. Furthermore, it is interesting to track the dynamics of chromosomes bearing 45S rDNA sites in the cell cycle as well as to observe the expression of FSs with no effect of the mitotic block. We observed variation in both the number and size of 45S FISH signals from the S/G2 phases of interphase and from prophase to anaphase where gaps in 45S rDNA sites also were observed. The change in the degree of condensation of the 45S site begins in the S/G2 phase and appears to be related to the transcriptional demand. Taking into account that the number of 45S rDNA sites tends to be re-established when cells reach telophase, we suggest that the chromatin fiber goes back to the normal condensation level to the anaphase (after segregation), allowing for the approximation of chromosome segments and ensuring dynamics that favor the genomic stability of these species.

Endoscopic management of bariatric surgery complications: what the gastroenterologist should know.

Obesity is a serious disorder in almost the entire world. It is an important risk factor for a series of conditions that affect and threaten health. Currently, bariatric surgery is the most effective treatment for morbid obesity, and in addition to the resulting weight loss, it reduces morbidity in this population. There has been a significant increase in the number of obese patients operated on. Despite the success of bariatric surgery, an important group of patients still present with major postoperative complications. In order for endoscopy to effectively contribute to the diagnosis and treatment of complications deriving from obesity surgery, the gastroenterologist must be aware of the particularities involved in bariatric surgery. The present article is a review of the resulting anatomic aspects of the main surgical techniques employed, the most common postoperative symptoms, the potential complications, and the possibilities that endoscopic diagnosis and treatment offer. Endoscopy is a growing and continuously evolving method in the treatment of bariatric surgery complications. The aim of this review is to contribute to the preparation of gastroenterologists so they can offer adequate endoscopic diagnosis and treatment to this high-risk population.

Leishmanicidal activity of the venoms of the Scorpions Brotheas amazonicus and Tityus metuendus.

Leishmaniasis is a vector-transmitted zoonosis caused by different species of the genus Leishmania, with a wide clinical spectrum. It is a public health problem aggravated by a series of limitations regarding treatment. In the search for new therapeutic alternatives, scorpion venoms are a source of multifunctional molecules that act against the natural resistance of pathogens. This work evaluated the antileishmanial potential of Brotheas amazonicus and Tityus metuendus venoms against the promastigote forms of Leishmania amazonensis e Leishmania guyanensis. The venoms of B. amazonicus and T. metuendus were evaluated for their constituents using Fourier Transform Infrared (FTIR). Growth inhibition and death of promastigotes were evaluated in the presence of diferente crude venom concentrations (100 µg/mL, 50 µg/mL, 10 µg/mL, 1 µg/mL) after one hour of incubation at 25 °C. The FTIR spectra of both venoms exhibited bands in approximate regions, revealing that both exhibit similar functional groups. Crude venom from both scorpion species showed similar or superior leishmanicidal effects to the standart drug N-methylglucamine antimoniate. At the highest concentration of 100 µg/mL, cultures of L. guyanensis treated with the venom of B. amazonicus showed the highest mortality percentages, above 28%, while T. metuendus venom showed the highest activity against L. amazonensis, with mortality above 7%. This preliminar study demonstrates that B. amazonicus and T. metuendus venoms can be important tools in the search for new drugs Against leishmaniasis. Next step involves evaluating the activity against the amastigote forms and purifying the venom proteins in order to identify the best anti-leishmania candidates.

Expression of recombinant human mutant granulocyte colony stimulating factor (Nartograstim) in Escherichia coli.

The human granulocyte colony stimulating factor (hG-CSF) plays an important role in hematopoietic cell proliferation/differentiation and has been widely used as a therapeutic agent for treating neutropenias. Nartograstim is a commercial G-CSF that presents amino acid changes in specific positions when compared to the wild-type form, which potentially increase its activity and stability. The aim of this work was to develop an expression system in Escherichia coli that leads to the production of large amounts of a recombinant hG-CSF (rhG-CSF) biosimilar to Nartograstim. The nucleotide sequence of hg-csf was codon-optimized for expression in E. coli. As a result, high yields of the recombinant protein were obtained with adequate purity, structural integrity and biological activity. This protein has also been successfully used for the production of specific polyclonal antibodies in mice, which could be used in the control of the expression and purification in an industrial production process of this recombinant protein. These results will allow the planning of large-scale production of this mutant version of hG-CSF (Nartograstim), as a potential new biosimilar in the market.

A vaccine against S. pyogenes: design and experimental immune response.

Streptococcus pyogenes causes severe invasive infections: the post-streptococcal sequelae of acute rheumatic fever (RF) and rheumatic heart disease (RHD), acute glomerulonephritis, and uncomplicated pharyngitis and pyoderma. Efforts to produce a vaccine against S. pyogenes began several decades ago, and different models have been proposed. Here, we describe the methodology used in the development of a new vaccine model, consisting of both T and B protective epitopes constructed as synthetic peptides and recombinant proteins. Two adjuvants were tested in an experimental inbred mouse model: a classical Freund's adjuvant and a new adjuvant (AFCo1) that induces mucosal immune responses and is obtained by calcium precipitation of a proteoliposome derived from the outer membrane of Neisseria meningitides B. The StreptInCor vaccine epitope co-administrated with AFCo1 adjuvant induced mucosal (IgA) and systemic (IgG) antibodies as preferential Th1-mediated immune responses. No autoimmune reactions were observed, suggesting that the vaccine epitope is safe.

Changes in levels of essential elements in suckling rats exposed to zinc and mercury.

The effect of mercury and its interaction with zinc on the content of essential metals in tissues from neonate rats was investigated. Three-day-old Wistar rats were treated with saline or 27 mg kg(-1)d(-1) ZnCl2 (s.c.) for five consecutive days. From the 8th to the 12th day of life, the rats received one daily dose of saline or 5.0 mg kg(-1) HgCl2 (s.c). Twenty-four hours after the last injection liver, kidneys and blood were collected for metal quantification. The HgCl(2) exposure induced alterations on metal levels, such as increase of Fe, Hg and Zn in liver, decrease of Fe and Mg and increase of Cu and Hg contents in kidneys. The Hg exposure also increased Hg levels in the blood. The treatment with ZnCl2, administered previously to HgCl2, partially prevented the increase of Fe in the liver, and not only prevented the decrease of renal Mg but also increased it to levels higher than those found in control group. The Zn-Hg rats also presented higher renal Cu levels, and showed partially lower blood and hepatic Hg levels and higher renal Hg levels. The pre-administration of Zn caused no severe alterations in levels of essential metals (Cu, Fe, Mg and Mn). In short, Zn appears to be an alternative treatment of Hg poisoning in young animals in comparison to chelating drugs since these have low metal selectivity.

Variations in behavior, innate immunity and host resistance to B16F10 melanoma growth in mice that present social stable hierarchical ranks.

The present study analyzed the effect of social stable hierarchical dominance/submissive relationships in C57BL/6 mice on behavior, innate immunity, serum corticosterone levels and host resistance to B16F10 melanoma growth. Adult mice (90 days old) kept in pairs since weaning, were analyzed for dominant/submissive ranking in three consecutive days according to the presence or absence of fighting and/or anticipatory submissive responses. Only the pairs of mice where dominant/submissive relationships were clearly stated were employed. Results showed that submissive mice presented in relation to dominants: (1) decreased time spent in the central open-field area; (2) decreased number of entries into the open arms and decreased time spent in the exploration of the open arms of the plus maze; (3) increased time spent in exploration of the plus-maze closed arms; (4) decreased number of entries and in the time spent in the exploration of the third part of the plus-maze open arms; (5) increased number of B16F10 metastasis in the lungs; (6) decreased NK cell cytotoxicity measured in vitro in the peripheral blood and spleen; (7) decreased basal but not in S. aureus induced oxidative burst in both neutrophils and monocytes and (8) similar basal serum levels of corticosterone. The present behavioral findings show that submissive mice, within a stable social hierarchy, present anxiety like-responses a fact that would make than more prone to stressful stimuli. This condition would be responsible for the decreases presently observed on basal neutrophil oxidative burst, NK cell activity and resistance to B16F10 tumor growth. Together the obtained data show that mice that present stable hierarchical relationships display neuro-immune alterations comparable to those reported in mice under a situation of chronic social stress.

Efficacy and safety of flexible-dose oral sildenafil citrate (Viagra) in the treatment of erectile dysfunction in Brazilian and Mexican men.

A 12-week, double-blind, placebo-controlled, multicenter study evaluated the efficacy and safety of flexible-dose sildenafil citrate (Viagra) treatment (25, 50 or 100 mg) in Brazilian and Mexican men with erectile dysfunction (ED) of broad-spectrum etiology. Efficacy was assessed on the basis of responses to the 15-item International Index of Erectile Function (IIEF) questionnaire, completed at baseline and after 12 weeks of treatment. At end point, mean scores for all IIEF domains of sexual function (erectile function, orgasmic function, sexual desire, intercourse satisfaction and overall satisfaction) were significantly (P<0.0001) higher in the sildenafil group (n=109) than in the placebo group (n=105). These findings confirm the significant increases in frequency of penetration and frequency of maintained erections reported previously. Sildenafil treatment was well tolerated. The most common adverse events were headache and flushing. In conclusion, sildenafil is a well-tolerated and effective treatment for ED of broad-spectrum etiology in Latin American men.

Differential effects of bromopride and domperidone on cholinesterase activity in rat tissues.

Bromopride (BRO) and domperidone (DOMP) are dopamine D2 blocking agents used in gastroenterology clinics because of their anti emetic effect as well as their central and peripheral actions of increasing gastrointestinal motor activity. The rationale for these experiments was to compare BRO- and DOMP-effects on plasma, brain, and intestinal cholinesterase activity in vitro. BRO and DOMP effects on cholinesterase activity in plasma, striatum, duodenum and ileum of adult male rats were measured for drug concentrations ranging from 0.006 to 3.134 microM for BRO and from 0.006 to 125 microM for DOMP. The results demonstrate that both BRO and DOMP can inhibit cholinesterase activity in all tissues studied, with DOMP being more potent than BRO in plasma and intestinal tissues. These data suggest the existence of a cholinergic mechanism of action for these dopamine blocking agents.

Evaluation of memory and anxiety in rats observed in the elevated plus-maze: effects of age and isolation.

Twenty young (5 months) and 20 old (20-24 months) male Wistar rats, isolated or group housed, were tested in the elevated plus-maze to evaluate memory and anxiety. Memory was quantified by transfer latency (the time it took for the rat to move from the open arm to the enclosed arm) and anxiety by percent entries into the open arms. Isolation decreased the transfer latency of old (session 1 = 119.33 +/- 0.44 s; session 3 = 49.67 +/- 12.12 s) and young (session 1 = 111.20 +/- 8.80 s; session 3 = 55.90 +/- 13.60 s) rats, but did not modify percent entries into the open arms (old-isolated = 5.56 +/- 5.56; old-group housed = 10.18 +/- 7.05; young-isolated = 35.16 +/- 8.98; young-group housed = 33.21 +/- 8.11). Conversely, aging decreased percent entries into the open arms but did not affect the transfer latency of isolated or group-housed animals. The results indicate that the plus-maze test, unlike other methods for memory evaluation, does not discriminate between young and old rats. They also suggest that age increases anxiety and that isolation increases memory levels, but that there is no interaction between age and isolation with regard to their effect on memory and anxiety in rats.

Malformations in neotropical viperids: qualitative and quantitative analysis.

Malformations can occur in all living species, but there is little information about anomalies that occur in snakes and their frequency. This study assessed malformations in newborn South American pit vipers (Bothrops jararaca) and South American rattlesnakes (Crotalus durissus) from wild captured pregnant females (240 and 35 litters, respectively). Newborn snakes were measured, weighed, sexed and studied grossly and by radiography for the presence of malformations. Ninety-five malformed pit vipers were identified from 4,087 births (2.3%), while 36 malformed rattlesnakes were found from 324 births (11.1%). Spinal abnormalities were the most common in both species, followed by fusion of ventral scales. Pit vipers showed a greater range of malformations including schistosomia (22.1%), kinked tail (13.7%), bicephaly (3.1%) and hydrocephaly (2.1%).

Flow cytometry as a tool in the evaluation of blood leukocyte function in Chelonia mydas (Linnaeus, 1758) (Testudines, Cheloniidae).

Chelonia mydas is a sea turtle that feeds and nests on the Brazilian coast and a disease called fibropapillomatosis is a threat to this species. Because of this, it is extremely necessary to determine a methodology that would enable the analysis of blood leukocyte function in these sea turtles. In order to achieve this aim, blood samples were collected from C. mydas with or without fibropapillomas captured on the São Paulo north coast. Blood samples were placed in tubes containing sodium heparin and were transported under refrigeration to the laboratory in sterile RPMI 1640 cell culture medium. Leukocytes were separated by density gradient using Ficoll-PaqueTM Plus, Amershan Biociences. The following stimuli were applied in the assessment of leukocyte function: Phorbol Miristate-Acetate (PMA) for oxidative burst activity evaluation and Zymosan A (Saccharomyces cerevisiae) Bio Particles, Alexa Fluor 594 conjugate for phagocytosis evaluation. Three cell populations were identified: heterophils, monocytes and lymphocytes. Monocytes were the cells responsible for phagocytosis and oxidative burst.

Seletividade fisiológica de inseticidas utilizados em cultura cafeeira sobre ovos e adultos de Cryptolaemus montrouzieri Mulsant / Physiologic selectivity of pesticides used on coffee plantations on eggs and adults of Cryptolaemus montrouzieri Mulsant

Em cafeeiros, a associação de inimigos naturais com produtos fitossanitários seletivos é uma importante estratégia no manejo de pragas. O objetivo do presente estudo foi avaliar os efeitos letais e subletais de produtos fitossanitários utilizados na cultura cafeeira sobre ovos e adultos de Cryptolaemus montrouzieriMulsant em laboratório. Os bioensaios foram realizados sob 25 ± 2º C, UR de 70 ± 10% e fotofase de 12h. Os inseticidas utilizados e suas respectivas dosagens de aplicação, em g ou mL de i.a. L-1 foram: tiametoxam (0,5), imidacloprido (0,7), óleo mineral (13,3), endossulfam (2,63) e dimetoato (0,48). A testemunha foi composta apenas por água destilada. A aplicação dos produtos foi realizada por meio de torre de Potter. Avaliaram-se a viabilidade de ovos, a sobrevivência dos espécimes e os efeitos dos compostos sobre os parâmetros reprodutivos do predador. Tiametoxam provocou prolongamento na duração do período embrionário (7,1 dias) em ovos tratados e junto com imidacloprido foram classificados como nocivos, seguidos do endossulfam e dimetoato que apresentaram toxicidade intermediária e do óleo mineral que foi seletivo. Em função da seletividade do óleo mineral, pode-se recomendá-lo visando à compatibilização com o predador C. montrouzieri em programas de manejo integrado de pragas na cultura cafeeira.

On coffee plantations, the association between selective compounds and natural enemies composes an important tool for the pest management. The objective of this study was to evaluate some pesticides used on coffee plantations in regard to their lethal and sublethal effects on eggs and adults of Cryptolaemus montrouzieri Mulsant under laboratory conditions. The bioassays were carried out in the Laboratory of Selectivity Studies, Department of Entomology of the Universidade Federal de Lavras ­ UFLA, Brazil, under controlled conditions (climatic chamber) at 25 ± 2º C, RH of 70 ± 10% with a 12 h photophase. The pesticides and doses in g or mL of i.a. L-1 were: thiamethoxam (0.5), imidacloprid (0.7), mineral oil (13.3), endosulfan (2.63) and dimethoate (0.48). Distilled water was used as a control. The sprayings of the pesticides were accomplished using a Potter's tower. The parameters evaluated were: specimen survival after the application of the compounds, oviposition and eggs viability. Thiamethoxam, imidacloprid and endosulfan were the most harmful to the treated individuals. When sprayed on eggs, thiamethoxam increased the embryonic period length (7.1 days). Mineral oil was the only compound that did not affect the reproduction of C. montrouzieri. In function of the selectivity presented by mineral oil, it can be recommended to be used in integrated pest management on coffee plantations in association with this predator.

Endemic goitre in Guinea-Bissau.

A survey was performed of endemic goitre in the Oio, Gabu, and Cacheu regions of Guinea-Bissau. Among adult women, the following prevalences of goitre were observed: 53% (Oio), 48% (Gabu), and 27% (Cacheu). For goitres of grades 2 and 3 only, the prevalences were 20% (Oio), 13% (Gabu), and 2% (Cacheu). No cretinism or cases of thyroid dysfunction were found. The mean urinary iodine excretions in Oio, Gabu, and Cacheu were 17 micrograms/g, 24 micrograms/g and 33 micrograms/g creatinine, respectively.

Immune-induced flavor aversion in mice: modification by neonatal capsaicin treatment.

OBJECTIVE: This study was designed to evaluate the role of c-sensitive fibers in the establishment of immune-induced flavor aversion in mice. METHODS: Mice were treated neonatally with capsaicin in order to destroy c-sensitive fibers; after such treatment, adult animals, immunized or not with ovalbumin, were submitted to a two-bottle preference test, with a choice between water and a sweetened egg white solution. RESULTS: Neonatal capsaicin treatment was unsuccessful in preventing the development of immune-induced aversion to the sweetened solution containing the antigen. Nonetheless, amongst immunized mice, those which had been previously treated with capsaicin showed a significant increment in the preference for the sweetened egg white solution. Furthermore, our data showed that neonatal capsaicin treatment did not interfere with either IgG1 or IgE production. CONCLUSION: The present results suggest that c-sensitive fibers have a role in the transmission of the signals generated by this immune response to the central nervous system, thus contributing to the development of a flavor aversion in mice.

Flow cytometry as a tool in the evaluation of blood leukocyte function in Chelonia mydas (Linnaeus, 1758) (Testudines, Cheloniidae) / A citometria de fluxo como ferramenta para avaliar a função celular de leucócitos sangüíneos de Chelonia mydas (Testudines, Cheloniidae)

Chelonia mydas is a sea turtle that feeds and nests on the Brazilian coast and a disease called fibropapillomatosis is a threat to this species. Because of this, it is extremely necessary to determine a methodology that would enable the analysis of blood leukocyte function in these sea turtles. In order to achieve this aim, blood samples were collected from C. mydas with or without fibropapillomas captured on the São Paulo north coast. Blood samples were placed in tubes containing sodium heparin and were transported under refrigeration to the laboratory in sterile RPMI 1640 cell culture medium. Leukocytes were separated by density gradient using Ficoll-PaqueTM Plus, Amershan Biociences®. The following stimuli were applied in the assessment of leukocyte function: Phorbol Miristate-Acetate (PMA) for oxidative burst activity evaluation and Zymosan A (Saccharomyces cerevisiae) Bio Particles®, Alexa Fluor® 594 conjugate for phagocytosis evaluation. Three cell populations were identified: heterophils, monocytes and lymphocytes. Monocytes were the cells responsible for phagocytosis and oxidative burst.

Chelonia mydas é uma tartaruga marinha que freqüenta o litoral brasileiro para alimentação e nidificação e uma doença denominada fibropapilomatose é uma das mais importantes ameaças à sobrevivência dessa espécie. Desta forma, a definição de uma metodologia que permita analisar a função dos leucócitos sangüíneos torna-se extremamente necessária. Foram utilizadas amostras sangüíneas de C. mydas com e sem fibropapilomas capturadas no litoral norte do estado de São Paulo. As amostras sangüíneas foram colocadas em tubos contendo heparina sódica e transportadas em meio de cultura celular RPMI 1640 estéril e sob refrigeração. Os leucócitos foram obtidos por gradiente de densidade usando Ficoll-PaqueTM Plus, Amershan Biociences®. Os estímulos aplicados foram Miristato Acetato de Phorbol (PMA) para avaliação de burst oxidativo e Zymosan A (Saccharomyces cerevisiae) Bio Particles®, Alexa Fluor® 594 conjugate para avaliação de fagocitose. Foram identificadas três populações celulares: heterófilos, monócitos e linfócitos. Os monócitos foram as células responsáveis pela fagocitose e pelo burst oxidativo.

Pielonefrite xantogranulomatosa: complicacao incomum. / Xanthogranulomatous pyelonephritis: unusual complication

Um caso de pielonefrite xantogranulomatosa e relatado, no qual se diagnosticou fistula renocolica espontanea, ocorrencia ainda nao descrita como complicacoes dessa doenca. Procura-se dar enfase as dificuldades diagnosticas pre-operatorias, mostrando-se alguns dados de historia e exame fisico que podem fazer pensar nesse tipo de afeccao cronica