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Early plants began colonizing earth about 450 million years ago. During the process of coevolution, their metabolic cellular pathways produced a myriad of natural chemicals, many of which remain uncharacterized biologically. Popular preparations containing some of these molecules have been used medicinally for thousands of years. In Brazilian folk medicine, plant extracts from the bamboo plant Guadua paniculata Munro have been used for the treatment of infections and pain. However, the chemical basis of these therapeutic effects has not yet been identified. Here, we performed protein biochemistry and downstream pharmacological assays to determine the mechanisms underlying the anti-inflammatory and antinociceptive effects of an aqueous extract of the G. paniculata rhizome, which we termed AqGP. The anti-inflammatory and antinociceptive effects of AqGP were assessed in mice. We identified and purified a protein (AgGP), with an amino acid sequence similar to that of thaumatins (~20 kDa), capable of repressing inflammation through downregulation of neutrophil recruitment and of decreasing hyperalgesia in mice. In conclusion, we have identified the molecule and the molecular mechanism responsible for the anti-inflammatory and antinociceptive properties of a plant commonly used in Brazilian folk medicine.

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Neuroinflammation is an important factor contributing to cognitive impairment and neurodegenerative diseases, including Alzheimer's disease (AD), Parkinson's disease (PD), Amyotrophic lateral sclerosis (ALS), ischemic injury, and multiple sclerosis (MS). These diseases are characterized by inexorable progressive injury of neuron cells, and loss of motor or cognitive functions. Microglia, which are the resident macrophages in the brain, play an important role in both physiological and pathological conditions. In this review, we provide an updated discussion on the role of ROS and metabolic disease in the pathological mechanisms of activation of the microglial cells and release of cytotoxins, leading to the neurodegenerative process. In addition, we also discuss in vivo models, such as zebrafish and Caenorhabditis elegans, and provide new insights into therapeutics bioinspired by neuropeptides from venomous animals, supporting high throughput drug screening in the near future, searching for a complementary approach to elucidating crucial mechanisms associated with neurodegenerative disorders.

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In order to discover a new compound having anti-inflammatory activity, a nitro-Schiff base was evaluated. The compound was synthesized and characterized by 1H NMR and 13C NMR. The cytotoxic activity was evaluated in vitro by hemolysis and MTT cell viability assay. To evaluate genotoxicity, the micronucleus assay was performed in vivo. The anti-inflammatory effects of the compound were examined using in vivo models of inflammation such as neutrophil migration assay, paw edema, and exudation assay. The production of NO was also estimated in vivo and in vitro. The data showed that the compound did not induce hemolysis at all the tested concentrations. Similarly, the compound did not induce cytotoxicity and genotoxicity to the cells. The neutrophil migration assay showed that the compound reduced the number of neutrophils recruited to the peritoneal cavity by approximately 60% at all the tested concentrations. In the exudation assay, the compound showed a reduction in extravasation by 24%. The paw edema model demonstrated a significant reduction in the paw volume at all the evaluated time points. The production of NO was decreased both in vitro and in vivo. These results suggest that the nitro-Schiff base compound efficiently inhibited inflammation and might be a good candidate for the treatment of inflammatory-associated conditions.

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Heart failure (HF) is a syndrome characterized basically by a circulatory deficit to cover the metabolic and energetic demands of the body. This condition has a broad spectrum in its clinical presentation, affects the quality of life significantly, impacts the family/social environment, and generates a great demand for health services. The purpose of this research is to report the situational diagnose of patients with HF in Mexico. We evaluated 292 patients, 70.2% were men. Average age was 56.7 ± 14.3 years. Ischemic heart disease is the main etiology (98 patients, 33.9%) followed by hypertensive (22.6%) and idiopathic (23.3%) heart disease. The associated clinical background was obesity (31.1%), systemic hypertension (36.7%), myocardial infarction (26.4%), and dyslipidemia (15.1%). The most common symptom was stress dyspnea (41.4%) and jugular vein engorgement at physical examination (32.5%). Anemia was observed in 1% of patients. The average left ventricular ejection fraction was 29.2 ± 10.6%. Sinus rhythm was the most frequently detected in 84.9%. 19.9% of patients had an implantable cardioverter-defibrillator or cardiac resynchronization therapy. 13.7% of patients with QRS > 130 ms. In our population, the meta-analysis global group in chronic heart failure risk score calculated was 16.8 ± 5.7 and for EMPHASIS 3.3 ± 1.5. We observed that age at presentation in HF in this analysis is at least 10 years younger than in other reports. The grade of obesity takes relevance in our group. The association of anemia and HF in Mexico is rare.

La insuficiencia cardiaca es un síndrome caracterizado fundamentalmente por un déficit circulatorio para cubrir las demandas metabólicas y energéticas del organismo. Esta entidad tiene un amplio espectro en su presentación clínica, afecta de manera significativa la calidad de vida, impacta en el entorno familiar/social y genera una gran demanda de los servicios de salud. El propósito de esta investigación es reportar el diagnóstico situacional de pacientes con insuficiencia cardiaca (IC) en México. Evaluamos 292 enfermos, 70.2% eran hombres. Con edad promedio 56.7 ± 14.3 años. La principal etiología es la cardiopatía isquémica (33.9%), seguida de la hipertensiva (22.6%) e idiopática (23.3%). Los antecedentes clínicos asociados fueron: obesidad (31.1%), hipertensión arterial sistémica (36.7%), infarto al miocardio (26.4%) y dislipidemia (15.1%). El síntoma con mayor presentación fue la disnea de esfuerzos (41.4%) y a la exploración física la ingurgitación yugular (32.5%). Se observó anemia en 1% de los enfermos. La fracción de expulsión del ventrículo izquierdo (FEVI) promedio fue de 29.2 + 10.6%. El ritmo sinusal fue el más frecuentemente detectado en 84.9%. El 19.9% de los pacientes tenían instalado un desfibrilador automático implantable (DAI) o tratamiento de resincronización cardiaca (TRC). El 13.7% de los enfermos con QRS mayor de 130 ms. El riesgo (MAGGIC) calculado en nuestro grupo poblacional fue de 16.8 ± 5.7 y para EMPHASIS 3.3 ± 1.5. Observamos que la edad de presentación de la IC en el presente análisis es menor por 10 años en comparación con otros reportes. El grado de obesidad toma relevancia en nuestro grupo. La asociación de anemia e IC en México es poco frecuente.

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Abstract Heart failure (HF) is a syndrome characterized basically by a circulatory deficit to cover the metabolic and energetic demands of the body. This condition has a broad spectrum in its clinical presentation, affects the quality of life significantly, impacts the family/social environment, and generates a great demand for health services. The purpose of this research is to report the situational diagnose of patients with HF in Mexico. We evaluated 292 patients, 70.2% were men. Average age was 56.7 +- 14.3 years. Ischemic heart disease is the main etiology (98 patients, 33.9%) followed by hypertensive (22.6%) and idiopathic (23.3%) heart disease. The associated clinical background was obesity (31.1%), systemic hypertension (36.7%), myocardial infarction (26.4%), and dyslipidemia (15.1%). The most common symptom was stress dyspnea (41.4%) and jugular vein engorgement at physical examination (32.5%). Anemia was observed in 1% of patients. The average left ventricular ejection fraction was 29.2 +- 10.6%. Sinus rhythm was the most frequently detected in 84.9%. 19.9% of patients had an implantable cardioverter-defibrillator or cardiac resynchronization therapy. 13.7% of patients with QRS > 130 ms. In our population, the meta-analysis global group in chronic heart failure risk score calculated was 16.8 +- 5.7 and for EMPHASIS 3.3 +- 1.5. We observed that age at presentation in HF in this analysis is at least 10 years younger than in other reports. The grade of obesity takes relevance in our group. The association of anemia and HF in Mexico is rare.

Resumen La insuficiencia cardiaca es un síndrome caracterizado fundamentalmente por un déficit circulatorio para cubrir las demandas metabólicas y energéticas del organismo. Esta entidad tiene un amplio espectro en su presentación clínica, afecta de manera significativa la calidad de vida, impacta en el entorno familiar/social y genera una gran demanda de los servicios de salud. El propósito de esta investigación es reportar el diagnóstico situacional de pacientes con insuficiencia cardiaca (IC) en México. Evaluamos 292 enfermos, 70.2% eran hombres. Con edad promedio 56.7 +- 14.3 años. La principal etiología es la cardiopatía isquémica (33.9%), seguida de la hipertensiva (22.6%) e idiopática (23.3%). Los antecedentes clínicos asociados fueron: obesidad (31.1%), hipertensión arterial sistémica (36.7%), infarto al miocardio (26.4%) y dislipidemia (15.1%). El síntoma con mayor presentación fue la disnea de esfuerzos (41.4%) y a la exploración física la ingurgitación yugular (32.5%). Se observó anemia en 1% de los enfermos. La fracción de expulsión del ventrículo izquierdo (FEVI) promedio fue de 29.2 + 10.6%. El ritmo sinusal fue el más frecuentemente detectado en 84.9%. El 19.9% de los pacientes tenían instalado un desfibrilador automático implantable (DAI) o tratamiento de resincronización cardiaca (TRC). El 13.7% de los enfermos con QRS mayor de 130 ms. El riesgo (MAGGIC) calculado en nuestro grupo poblacional fue de 16.8 +- 5.7 y para EMPHASIS 3.3 +- 1.5. Observamos que la edad de presentación de la IC en el presente análisis es menor por 10 años en comparación con otros reportes. El grado de obesidad toma relevancia en nuestro grupo. La asociación de anemia e IC en México es poco frecuente.

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BACKGROUND AND OBJECTIVE: Asenapine is an atypical antipsychotic approved by US Food and Drug Administration in 2009 and by European Medicines Agency in 2010 for Schizophrenia and Bipolar Disorder treatment. Currently, many studies have been developed in an attempt to clarify and minimize the risks related to the use of psychotropic during pre/postnatal period on patients with a history of mental disorders. CONCLUSION: The aim of this study was to test the impact of pre and/or postnatal exposition to asenapine on mice offspring behavior. Four groups of animals, previously treated with a dosage equivalent to 50% of the bioavailability obtained with a 20 mg daily use for human treatment, were exposed to the Open Field and Elevated plus Maze test. Only the group exposed to asenapine during both pre and postnatal periods showed response difference in the Elevated Plus Maze test, which was restricted to urination. However, our data suggest that the administration of asenapine does not induce significant anxiety-like behaviors in mice.

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BACKGROUND: Effect of Heteropterys aphrodisiaca (dog-node) on anxiety and function of adult female wistar mice. The project is an experiment with the use of H. aphrodisiac root extract, in order to observe the frequency of sexual exposure of females exposed to the extract, quantify the effect of the extract on the concentration of total testosterone and observe the anxiety levels of the animals exposed. Results will be measured with the laboratory testosterone test and LCE and CA tests. METHODS: In preparation of the extract, the root was oven dried at 40°C and diluted in alcohol extract (100g of root for 1 liter of alcohol) and lyophilized. 40 adult female mice were enrolled, separated in control group (placebo) and treatment group (50 mg/kg/day) for 15, 30, 45 and 60 days. At each period, hormonal testosterone and anxiety levels by the Elevated-Cross Labyrinth (ECL) tests and Open Camp (CA) were measured in 10 animals that were later euthanized (SBNeC). RESULTS: The results showed an improvement in the decrease of anxiety, as shown in the variables of number of open arm entries, time on the same side of the field, less avoidance and leakage. However, it appears that the time of exposure to the extract does not result in increased benefit, with possible decline of effect after 45 days of use. CONCLUSION: With this performed experiment with the "no-de-cachorro" extract, it was possible to understand a little more how this root can act in relation to anxiety, as predicted by the pharmacology that validates the animal models; anxiolytic components decrease anxiety-related behaviors, as shown in the variables of entry numbers in the open arm, time on the same side of the field, less avoidance and escape. However, it seems that the time of exposure to the extract does not modify the performance in the tests, observing until an apparent exhaustion of the anxiolytic action, which evidences the need for more specific studies on the possible effects of the extract.

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Helicobacter spp. is a spiral Gram-negative bacterium that has substantial clinical importance. It has been related to diseases such as gastritis and peptic ulcers, and more recently to gastric cancer in humans. Evidence suggests the potential of animals, particularly domestic ones, as the source of zoonotic infection of helicobacteria since bacteria with similar morphology to those found in animals were observed in the stomach of humans with gastritis. Thus, dogs have been identified to serve as an important host for infectious agents such as Helicobacter spp. From this perspective, the present study aimed to assess the prevalence of Helicobacter spp. in dogs from the Zoonosis Control Center of Campo Grande-MS. Samples of body, fundus, and gastric antrum from 96 dogs were collected to evaluate the presence of Helicobacter spp. through the rapid urease test and histological analysis. Helicobacter spp. was found in 94.7% of the dogs by rapid urease test and in 100% by histological analysis, with bacteria predominance in the stomach fundus region.

A Helicobacter spp. é uma bactéria Gram negativa espiralada, de grande importância clínica, que se relaciona a patogenias como gastrite e úlceras pépticas e, mais recentemente, com o carcinoma gástrico em humanos. Evidências sugerem o potencial dos animais, principalmente os domésticos, como fonte de infecção zoonótica das helicobactérias, já que bactérias com morfologia similar às encontradas em animais foram observadas no estômago de humanos com gastrite. Nesse contexto, os cães podem ser um importante reservatório de agentes infecciosos como a Helicobacter spp. O presente trabalho teve como objetivo avaliar a prevalência de Helicobacter spp. em cães do Centro de Controle de Zoonoses de Campo Grande/MS. Para tanto, foram utilizados 96 cães dos quais foram colhidas amostras do corpo, fundo e antro gástrico, para avaliação da presença da Helicobacter spp. por meio do teste rápido de urease e análise histológica. O teste rápido de urease permitiu a detecção deHelicobacter spp. em 94,7% dos cães; já a análise histológica indicou a presença de Helicobacter spp. em 100% dos animais avaliados com predomínio da bactéria na região do fundo do estômago.

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Helicobacter spp. is a spiral Gram-negative bacterium that has substantial clinical importance. It has been related to diseases such as gastritis and peptic ulcers, and more recently to gastric cancer in humans. Evidence suggests the potential of animals, particularly domestic ones, as the source of zoonotic infection of helicobacteria since bacteria with similar morphology to those found in animals were observed in the stomach of humans with gastritis. Thus, dogs have been identified to serve as an important host for infectious agents such as Helicobacter spp. From this perspective, the present study aimed to assess the prevalence of Helicobacter spp. in dogs from the Zoonosis Control Center of Campo Grande-MS. Samples of body, fundus, and gastric antrum from 96 dogs were collected to evaluate the presence of Helicobacter spp. through the rapid urease test and histological analysis. Helicobacter spp. was found in 94.7% of the dogs by rapid urease test and in 100% by histological analysis, with bacteria predominance in the stomach fundus region.(AU)

A Helicobacter spp. é uma bactéria Gram negativa espiralada, de grande importância clínica, que se relaciona a patogenias como gastrite e úlceras pépticas e, mais recentemente, com o carcinoma gástrico em humanos. Evidências sugerem o potencial dos animais, principalmente os domésticos, como fonte de infecção zoonótica das helicobactérias, já que bactérias com morfologia similar às encontradas em animais foram observadas no estômago de humanos com gastrite. Nesse contexto, os cães podem ser um importante reservatório de agentes infecciosos como a Helicobacter spp. O presente trabalho teve como objetivo avaliar a prevalência de Helicobacter spp. em cães do Centro de Controle de Zoonoses de Campo Grande/MS. Para tanto, foram utilizados 96 cães dos quais foram colhidas amostras do corpo, fundo e antro gástrico, para avaliação da presença da Helicobacter spp. por meio do teste rápido de urease e análise histológica. O teste rápido de urease permitiu a detecção deHelicobacter spp. em 94,7% dos cães; já a análise histológica indicou a presença de Helicobacter spp. em 100% dos animais avaliados com predomínio da bactéria na região do fundo do estômago.(AU)

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Abstract Helicobacter spp. is a spiral Gram-negative bacterium that has substantial clinical importance. It has been related to diseases such as gastritis and peptic ulcers, and more recently to gastric cancer in humans. Evidence suggests the potential of animals, particularly domestic ones, as the source of zoonotic infection of helicobacteria since bacteria with similar morphology to those found in animals were observed in the stomach of humans with gastritis. Thus, dogs have been identified to serve as an important host for infectious agents such as Helicobacter spp. From this perspective, the present study aimed to assess the prevalence of Helicobacter spp. in dogs from the Zoonosis Control Center of Campo Grande-MS. Samples of body, fundus, and gastric antrum from 96 dogs were collected to evaluate the presence of Helicobacter spp. through the rapid urease test and histological analysis. Helicobacter spp. was found in 94.7% of the dogs by rapid urease test and in 100% by histological analysis, with bacteria predominance in the stomach fundus region.

Resumo A Helicobacter spp. é uma bactéria Gram negativa espiralada, de grande importância clínica, que se relaciona a patogenias como gastrite e úlceras pépticas e, mais recentemente, com o carcinoma gástrico em humanos. Evidências sugerem o potencial dos animais, principalmente os domésticos, como fonte de infecção zoonótica das helicobactérias, já que bactérias com morfologia similar às encontradas em animais foram observadas no estômago de humanos com gastrite. Nesse contexto, os cães podem ser um importante reservatório de agentes infecciosos como a Helicobacter spp. O presente trabalho teve como objetivo avaliar a prevalência de Helicobacter spp. em cães do Centro de Controle de Zoonoses de Campo Grande/MS. Para tanto, foram utilizados 96 cães dos quais foram colhidas amostras do corpo, fundo e antro gástrico, para avaliação da presença da Helicobacter spp. por meio do teste rápido de urease e análise histológica. O teste rápido de urease permitiu a detecção de Helicobacter spp. em 94,7% dos cães; já a análise histológica indicou a presença de Helicobacter spp. em 100% dos animais avaliados com predominio da bactéria na região do fundo do estômago.

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Capsicum baccatum is the most consumed red pepper species in Brazil. Our previous studies demonstrated the anti-inflammatory properties of its crude extract, whose activity is yet to be fully characterized. Herein, we examined the anti-inflammatory in vivo effects of enriched extracts obtained through bioguided fractionation as dichloromethane (DCM), butanol (BUT), and residual aqueous (RAq) extracts and its influence on inflammatory mediators produced by macrophages in vitro. We demonstrated that all C. baccatum extracts presented anti-inflammatory activity in vivo. In addition, we showed that BUT and RAq were more effective in inhibiting the neutrophil migration induced by carrageenan (Cg) to peritoneal cavity and both extracts inhibited paw edema induced by Cg, prostaglandin E2, and histamine in mice. Furthermore, the pretreatment with C. baccatum extracts significantly reduced the levels of myeloperoxidase (MPO) in the paw tissues of mice compared with the carrageenan group. Once again, RAq and BUT caused the greatest reduction in MPO levels. Moreover, it was demonstrated for the first time that C. baccatum inhibited the nitric oxide and tumor necrosis factor-alpha production by lipopolysaccharide/interferon gamma (IFN-γ)-stimulated macrophages. These anti-inflammatory effects seem to be at least, in part, independent of capsaicin. Hence, red pepper has bioactive compounds and might be used to develop food-derived extracts to treat related inflammatory diseases.

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The main bacterium associated with skin infection is Staphylococcus aureus, occurring especially in infections acquired via surgical wounds, commonly leading to lethal hospital-acquired infections, emphasizing the importance of identifying new antimicrobial compounds. Among them, cyclotides have gained interest due to their high stability and multifunctional properties. Here, cycloviolacin 2 (CyO2) and kalata B2 (KB2) were evaluated to determinate their anti-staphylococcal activities using a subcutaneous infection model. Anti-staphylococcal activities of 50mM for KB2 and 25mM for CyO2 were detected with no cytotoxic activities against RAW 264.7 monocytes. In the in vivo assays, both cyclotides reduced bacterial load and CyO2 demonstrated an increase in the phagocytosis index, suggesting that the CyO2 in vivo anti-staphylococcal activity may be associated with phagocytic activity, additionally to direct anti-pathogenic activity.

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CONTEXT: Bothrops moojeni Hoge (Viperidae) venom is a complex mixture of compounds with therapeutic potential that has been included in the research and development of new drugs. Along with the biological activity, the pharmaceutical applicability of this venom depends on its toxicological profile. OBJECTIVE: This study evaluates the cytotoxicity and genotoxicity of the Bothrops moojeni venom (BMV). MATERIAL AND METHODS: The in vitro cytotoxicity and genotoxicity of a pooled sample of BMV was assessed by the MTT and Comet assay, respectively. Genotoxicity was also evaluated in vivo through the micronucleus assay. RESULTS: BMV displayed a 50% cytotoxic concentration (CC50) on Vero cells of 4.09 µg/mL. Vero cells treated with 4 µg/mL for 90 min and 6 h presented significant (p < 0.05, ANOVA/Newman-Keuls test) higher DNA damage than the negative control in the Comet assay. The lower DNA damage found after 6 h compared with the 90 min treatment suggests a DNA repair effect. Mice intraperitoneally treated with BMV at 10, 30, or 80 µg/animal presented significant genotoxicity (p < 0.05, ANOVA/Newman-Keuls test) in relation to the negative control after 24 h of treatment. Contrary to the in vitro results, no DNA repair seemed to occur in vivo up to 96 h post-venom inoculation at a dose of 30 µg/animal. DISCUSSION AND CONCLUSION: The results show that BMV presents cyto- and genotoxicity depending on the concentration/dose used. These findings emphasize the importance of toxicological studies, including assessment of genotoxicity, in the biological activity research of BMV and/or in the development of BMV-derived products.

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The rapid increase in the incidence of multidrug-resistant infections today has led to enormous interest in antimicrobial peptides (AMPs) as suitable compounds for developing unusual antibiotics. In this study, clavanin A, an antimicrobial peptide previously isolated from the marine tunicate Styela clava, was selected as a purposeful molecule that could be used in controlling infection and further synthesized. Clavanin A was in vitro evaluated against Staphylococcus aureus and Escherichia coli as well as toward L929 mouse fibroblasts and skin primary cells (SPCs). Moreover, this peptide was challenged here in an in vivo wound and sepsis model, and the immune response was also analyzed. Despite displaying clear in vitro antimicrobial activity toward Gram-positive and -negative bacteria, clavanin A showed no cytotoxic activities against mammalian cells, and in acute toxicity tests, no adverse reaction was observed at any of the concentrations. Moreover, clavanin A significantly reduced the S. aureus CFU in an experimental wound model. This peptide also reduced the mortality of mice infected with E. coli and S. aureus by 80% compared with that of control animals (treated with phosphate-buffered saline [PBS]): these data suggest that clavanin A prevents the start of sepsis and thereby reduces mortality. These data suggest that clavanin A is an AMP that could improve the development of novel peptide-based strategies for the treatment of wound and sepsis infections.

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Controlling human pathogenic bacteria is a worldwide problem due to increasing bacterial resistance. This has prompted a number of studies investigating peptides isolated from marine animals as a possible alternative for control of human pathogen infections. Clavanins are antimicrobial peptides isolated from the marine tunicate Styela clava, showing 23 amino acid residues in length, cationic properties, and also high bactericidal activity. In spite of clear benefits from the use of peptides, currently 95% of peptide properties have limited pharmaceutical applicability, such as low solubility and short half-life in the circulatory system. Here, nanobiotechnology was used to encapsulate clavanin A in order to develop nanoantibiotics against bacterial sepsis. Clavanin was nanostructured using EUDRAGIT(®) L 100-55 and RS 30 D solution (3:1 w:w). Atomic force, scanning electron microscopy and dynamic light scattering showed nanoparticles ranging from 120 to 372 nm in diameter, with a zeta potential of -7.16 mV and a polydispersity index of 0.123. Encapsulation rate of 98% was assessed by reversed-phase chromatography. In vitro bioassays showed that the nanostructured clavanin was partially able to control development of Staphylococcus aureus, Klebsiella pneumoniae, and Pseudomonas aeruginosa. Furthermore, nanostructures did not show hemolytic activity. In vivo sepsis bioassays were performed using C57BL6 mice strain inoculated with a polymicrobial suspension. Assays led to 100% survival rate under sub-lethal sepsis assays and 40% under lethal sepsis assays in the presence of nanoformulated clavanin A until the seventh day of the experiment. Data here reported indicated that nanostructured clavanin A form shows improved antimicrobial activity and has the potential to be used to treat polymicrobial infections.

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Healthcare-associated infections (HAIs) are causes of mortality and morbidity worldwide. The prevalence of bacterial resistance to common antibiotics has increased in recent years, highlighting the need to develop novel alternatives for controlling these pathogens. Pitviper venoms are composed of a multifaceted mixture of peptides, proteins and inorganic components. L-amino oxidase (LAO) is a multifunctional enzyme that is able to develop different activities including antibacterial activity. In this study a novel LAO from Bothrops mattogrosensis (BmLAO) was isolated and biochemically characterized. Partial enzyme sequence showed full identity to Bothrops pauloensis LAO. Moreover, LAO here isolated showed remarkable antibacterial activity against Gram-positive and -negative bacteria, clearly suggesting a secondary protective function. Otherwise, no cytotoxic activities against macrophages and erythrocytes were observed. Finally, some LAO fragments (BmLAO-f1, BmLAO-f2 and BmLAO-f3) were synthesized and further evaluated, also showing enhanced antimicrobial activity. Peptide fragments, which are the key residues involved in antimicrobial activity, were also structurally studied by using theoretical models. The fragments reported here may be promising candidates in the rational design of new antibiotics that could be used to control resistant microorganisms.

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En el presente trabajo describimos el aislamiento y la actividad de biodegradación de microorganismos sobre polietileno de baja densidad. Los microorganismos fueron aislados de materiales plásticos con evidencias de deterioro procedentes de un relleno sanitario de Lima. Las muestras fueron filtradas y preseleccionadas en medio de sales minerales a pH 5,5 y 7, para hongos y bacterias respectivamente. Se aislaron 6 cepas, identificadas como Pseudomonas sp. MP3a y MP3b, Penicillium sp. MP3a, Rhodotorula sp. MP3b, Hyalodendron sp. MP3cy una levadura no identificada. La acción degradativa del consorcio microbiano aislado fue evidenciada porvariaciones en el espectro infrarrojo del polietileno con respecto al polímero sin tratamiento, observándose la reducción del índice de carbonilo (83,89% a pH 7 y 4,08% a pH 5,5) y de terminaciones con dobles enlaces (19,77% a pH 7 y 6,47% a pH 5,5). Finalmente se determinó el porcentaje de peso perdido por el polietileno sometido a las cepas aisladas, observándose una disminución de 5,4% a pH 7 y 4,8% a pH5,5.

In this paper, we describe the isolation and biodegradation activity of microorganisms on low density polyethylene. The microorganisms were collected from plastic materials with evidence of deterioration from a landfill. The samples were filtered and selected in a mineral salts medium at pH 5.5 and 7 for bacteria and fungi respectively. Six strains were isolated, identified as Pseudomonas sp. Hyalodendron sp., Penicillium sp. and Rhodotorula sp.Microbial activity was evidenced by changes in the infrared spectrum of polyethylene with respect to the polymer without treatment. Reduction of carbonyl index (83.89% at pH 7 and 4.08% at pH 5.5) and double bonds index (19.77% at pH 7 and 6.47% at pH 5.5) were observed. Finally we determined the percentage of weight lost by the polyethylene subjected to activity of the strains, with a decrease of 5.4% at pH 7 and 4.8% at pH5, 5.

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OBJETIVO. Determinar la evolución de la resistencia a la eritromicina, el cloranfenicol, el trimetoprim-sulfametozaxol (SXT) y la vancomicina de aislamientos invasores de Streptococcus pneumoniae obtenidos de niños de 10 países de América Latina y del Caribe en seis años de vigilancia. MÉTODOS. Se analizaron 8 993 aislamientos de S. pneumoniae recuperados entre 2000 y 2005 de niños menores de 6 años con infecciones invasoras, procedentes de Argentina, Brasil, Chile, Colombia, Cuba, México, Paraguay, República Dominicana, Uruguay y Venezuela. La sensibilidad a los antibióticos se determinó mediante los métodos establecidos y estandarizados en el proyecto SIREVA. La resistencia a múltiples antibióticos se definió como la resistencia a tres o más familias de antibióticos, de los no betalactámicos analizados en este estudio o de los betalactámicos evaluados en un estudio previo en el que 37,8% de estos aislamientos presentaron sensibilidad disminuida a la penicilina. RESULTADOS. Se encontró algún grado de resistencia al SXT y la eritromicina (56,4% y 15,4% de los aislamientos estudiados, respectivamente) y 4,6% presentó alta resistencia al cloranfenicol. Todos los aislamientos fueron sensibles a la vancomicina. Se observó la mayor frecuencia de resistencia al SXT en los aislamientos de neumonía y a la eritromicina en los casos de sepsis (61,6% y 25,5%, respectivamente; P < 0,01). La mayor frecuencia de resistencia al SXT se observó en Brasil (71,9%) y a la eritromicina en México (38,2%) y Venezuela (32,9%). Los serotipos 14, 6B, 19F y 23F fueron los que más frecuentemente se asociaron con la resistencia a los antibióticos estudiados. CONCLUSIONES. Se observó una elevada y creciente frecuencia de aislamientos resistentes al SXT y la eritromicina, y una disminución en la proporción de aislamientos resistentes al cloranfenicol. Estas tendencias mostraron diferencias entre los países estudiados.

OBJECTIVE. To examine the development of resistance to erythromycin, chloramphenicol, trimethoprim-sulfamethoxazole (TMP-SMZ), and vancomycin of the invasive isolates of Streptococcus pneumoniae obtained from children in 10 Latin American/Caribbean countries during six years of surveillance. METHODS. Analysis of 8 993 isolates of S. pneumoniae recovered in 2000­2005 from children with invasive infections, who were less than 6 years of age, and from Argentina, Brazil, Chile, Colombia, Cuba, Dominican Republic, Mexico, Paraguay, Uruguay, or Venezuela. Antibiotic susceptibility was determined through the methods established and standardized by the SIREVA project. Multidrug resistance was defined as: resistance to three or more antibiotics of the same class; to the non-beta-lactams analyzed by this study; or, to the beta-lactams evaluated by a previous study, in which 37.8% of these isolates showed decreased susceptibility to penicillin. RESULTS. Some degree of resistance was found to TMP-SMZ and erythromycin (56.4% and 15.4% of the isolates studied, respectively), with 4.6% highly resistant to chloramphenicol. All isolates were susceptible to vancomycin. The highest prevalence of TMP-SMZ resistance was observed in the pneumonia isolates; and that of erythromycin, in cases of sepsis (61.6% and 25.5%, respectively; P < 0.01). The highest prevalence of TMP-SMZ resistance was found in Brazil (71.9%), and that of erythromycin, in Mexico (38.2%) and Venezuela (32.9%). The 14, 6B, 19F, and 23F serotypes were most often associated with resistance to the antibiotics in the study. CONCLUSIONS. High and increasing rates of isolates resistant to TMP-SMZ and erythromycin were observed, as well as a decreasing percentage of isolates resistant to chloramphenicol. These trends highlight differences among the countries studied

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3-Hydroxy-3-methylglutaric aciduria is a rare autosomal recessive genetic disorder that affects ketogenesis and L-leucine catabolism. The clinical acute symptoms include vomiting, convulsions, metabolic acidosis, hypoketotic hypoglycaemia and lethargy. To date, 33 mutations in 100 patients have been reported in the HMGCL gene. In this study 10 new mutations in 24 patients are described. They include: 5 missense mutations: c.109G>A, c.425C>T, c.521G>A, c.575T>C and c.598A>T, 2 nonsense mutations: c.242G>A and c.559G>T, one small deletion: c.853delC, and 2 mutations in intron regions: c.497+4A>G and c.750+1G>A. Two prevalent mutations were detected, 109G>T (E37X) in 38% of disease alleles analyzed and c.504_505delCT in 10% of them. Although patients are mainly of European origin (71%) and mostly Spanish (54%), the group is ethnically diverse and includes, for the first time, patients from Pakistan, Palestine and Ecuador. We also present a simple, efficient method to express the enzyme and we analyze the possible functional effects of missense mutations. The finding that all identified missense mutations cause a >95% decrease in the enzyme activity, indicates that the disease appears only in very severe genotypes."

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