Neurotoxic activity and ultrastructural changes in muscles caused by the brown widow spider Latrodectus geometricus venom

Brown widow spider (Latrodectus geometricus) venom (BrWSV) produces few local lesions and intense systemic reactions such as cramps, harsh muscle pains, nausea, vomiting and hypertension. Approximately 16 protein bands under reducing conditions and ~ 14 bands under non-reducing conditions on a 12.5% sodium dodecyl sulfate-polyacrylamide gel electrophoresis were observed. Neurotoxic clinical manifestations were confirmed in vivo, while proteolytic activity was demonstrated on gelatine film. Severe ultrastructural damages in mice skeletal muscles were observed at 3, 6, 12 and 24 h postinjection with at total of 45 µg of venom protein. Infiltration of eosinophils and ruptures of the cellular membranes were observed in the muscles along with swelling of the nuclear cover and interruption of the collagen periodicity. Altered mitochondrias and autophage vacuoles, nuclear indentation and mitochondria without cristae, slight increment of intermyofibrillar and subsarcolemic spaces and myelinic figures formation were also observed. In the capillary, endothelial membrane unfolding into the lumen was noticed; along with myelinic figures compatible with a toxic myopathy. Swollen sarcotubular systems with lysis of membrane, intense mitochondria autophagia and areas without pinocytic vesicles were observed. Swollen mitochondria surrounded by necrotic areas, myofibrillar disorganization and big vacuolas of the sarcotubular system, degenerated mitochondrium with formation of myelinic figure was seen. Glycogenosomes with small particulate, muscle type glycogen was noticed. Autophagic vacuole (autophagolysosomes) and necrotic areas were also noticed. These damages may be due to interactive effects of the multifactorial action of venom components. However, Latrodectus geometricus venom molecules may also be utilized as neuro therapeutic tools, as they affect neuronal activities with high affinity and selectivity. To our knowledge, the present study is the first ultrastructural report in the literature of muscle injuries and neurological and proteolytic activities caused by BrWSV.

Effects of Chlorophenoxy Herbicides and Their Main Transformation Products on DNA Damage and Acetylcholinesterase Activity

Persistent pesticide transformation products (TPs) are increasingly being detected among different environmental compartments, including groundwater and surface water. However, there is no sufficient experimental data on their toxicological potential to assess the risk associated with TPs, even if their occurrence is known. In this study, the interaction of chlorophenoxy herbicides (MCPA, mecoprop, 2,4-D and dichlorprop) and their main transformation products with calf thymus DNA by UV-visible absorption spectroscopy has been assessed. Additionally, the toxicity of the chlorophenoxy herbicides and TPs was also assessed evaluating the inhibition of acetylcholinesterase activity. On the basis of the results found, it seems that AChE is not the main target of chlorophenoxy herbicides and their TPs. However, the results found showed that the transformation products displayed a higher inhibitory activity when compared with the parent herbicides. The results obtained in the DNA interaction studies showed, in general, a slight effect on the stability of the double helix. However, the data found for 4-chloro-2-methyl-6-nitrophenol suggest that this transformation product can interact with DNA through a noncovalent mode.

A score test for non-nested hypotheses with applications to discrete data models

This paper suggests that a convenient score test against non-nested alternatives can be constructed from the linear combination of the likelihood functions of the competing models. It is shown that this procedure is essentially a test for the correct specification of the conditional distribution of the variable of interest.

Antiviral activity of the green marine alga Ulva fasciata on the replication of human metapneumovirus

We evaluated the antiviral activity of the marine alga, Ulva fasciata, collected from Rasa beach and Forno beach, Búzios, Rio de Janeiro, Brazil on the replication of human metapneumovirus (HMPV). The algae extracts were prepared using three different methodologies to compare the activity of different groups of chemical composites obtained through these different methodologies. Four out of the six extracts inhibited nearly 100% of viral replication. The results demonstrated that the majority of the extracts (five out of six) possess virucidal activity and therefore have the ability to interact with the extracellular viral particles and prevent the infection. On the other hand, only two extracts (from Forno beach, obtained by maceration and maceration of the decoction) were able to interact with cell receptors, hindering the viral entry. Finally, only the extract of algae collected at Forno beach, obtained by maceration presented intracellular activity. To our knowledge, this is a pioneer study on antiviral activity of marine algae against HMPV. It is also the first on antiviral activity against HMPV ever done in Brazil. The study also shows the effect of different environment factors and different chemical procedures used to obtain the extract on its biological properties.

Modulatory activity of antioxidants against the toxicity of Rifampicin in vivo

The World Health Organization (WHO) has shown concern about the burden of tuberculosis in the developing countries. Even though rifampicin is an effective drug in the management of tuberculosis, it has been documented to have some toxic effects in humans. Therefore, this study intends to investigate the modulatory effect of vitamins C and E on the hepatotoxicity, sperm quality and brain toxicity of Rifampicin. Forty Wistar albino rats were used, 10 animals per group. Group 1 animals received 0.3 mL of distilled water, the Group 2 animals received the therapeutic dose of rifampicin, Group 3 animals received therapeutic doses of rifampicin plus vitamin E, while Group 4 received therapeutic doses of rifampicin and vitamin C. The administration was performed orally during three months; the animals were sacrificed by cervical dislocation at the end of that period. Blood samples were collected and liver function and lipid profile was analyzed using fully automated clinical chemistry device. The liver, brain and reproductive organs underwent histopathological examination. Sperm samples were collected from the epididymis to achieve count and motility and morphological analysis. Results showed rifampicin alone to raise (p < 0.05) liver function enzymes (Aspartate amino transferase [AST], Serum alanine amino transferase [ALT] and Total Bilirubin) when compared with controls. While the vitamin E treated group showed remarkable protection, the vitamin C treated group showed questionable protection against the rifampicin induced liver damage. Sperm count results showed an important (p < 0.05) increase in the sperm quality in vitamin E and C treated groups. However, the vitamin E plus Rifampicin treated group showed increased lipid peroxidation. The histopathological findings revealed structural damages by rifampicin in liver, brain and epididymis while some remarkable architectural integrity was observed in the antioxidant-treated groups. It can be concluded that vitamin E or C improved sperm quality and protected against the brain damage caused by rifampicin. Moreover, vitamin E demonstrated remarkable hepatoprotection against rifampicin induced damage while vitamin C shows a questionable hepatoprotection.

Physical Activity, Obesity Status, and Blood Pressure in Preschool Children

Objective To examine the combined effects of physical activity and weight status on blood pressure (BP) in preschool-aged children. Study design The sample included 733 preschool-aged children (49% female). Physical activity was objectively assessed on 7 consecutive days by accelerometry. Children were categorized as sufficiently active if they met the recommendation of at least 60 minutes daily of moderate-to-vigorous physical activity (MVPA). Body mass index was used to categorize children as nonoverweight or overweight/obese, according to the International Obesity Task Force benchmarks. BP was measured using an automated BP monitor and categorized as elevated or normal using BP percentile-based cut-points for age, sex, and height. Results The prevalence of elevated systolic BP (SBP) and diastolic BP was 7.7% and 3.0%, respectively. The prevalence of overweight/obese was 32%, and about 15% of children did not accomplish the recommended 60 minutes of daily MVPA. After controlling for age and sex, overweight/obese children who did not meet the daily MVPA recommendation were 3 times more likely (OR 3.8; CI 1.6-8.6) to have elevated SBP than nonoverweight children who met the daily MVPA recommendation. Conclusions Overweight or obese preschool-aged children with insufficient levels of MVPA are at significantly greater risk for elevated SBP than their non overweight and sufficiently active counterparts. (J Pediatr 2015;167:98-102).

Step based physical activity guidelines for preschool-aged children

Objective Public health organizations recommend that preschool-aged children accumulate at least 3 h of physical activity (PA) daily. Objective monitoring using pedometers offers an opportunity to measure preschooler's PA and assess compliance with this recommendation. The purpose of this study was to derive step-based recommendations consistent with the 3 h PA recommendation for preschool-aged children. Method The study sample comprised 916 preschool-aged children, aged 3 to 6 years (mean age = 5.0 ± 0.8 years). Children were recruited from kindergartens located in Portugal, between 2009 and 2013. Children wore an ActiGraph GT1M accelerometer that measured PA intensity and steps per day simultaneously over a 7-day monitoring period. Receiver operating characteristic (ROC) curve analysis was used to identify the daily step count threshold associated with meeting the daily 3 hour PA recommendation. Results A significant correlation was observed between minutes of total PA and steps per day (r = 0.76, p < 0.001). The optimal step count for ≥ 3 h of total PA was 9099 steps per day (sensitivity (90%) and specificity (66%)) with area under the ROC curve = 0.86 (95% CI: 0.84 to 0.88). Conclusion Preschool-aged children who accumulate less than 9000 steps per day may be considered Insufficiently Active.

The inhibitory activity of synthetic compounds and ions against transporters of multi-drug resistant bacteria

RESUMO: Sessenta e três derivados de hidantoína foram utilizados para avaliar possíveis efeitos de modulação na actividade das bombas de efluxo (BE) na Salmonella NCTC 13349 utilizando um método fluorimétrico semi-automático. Nenhum dos compostos apresentaram actividade anti-bacteriana até concentrações de 240 mg/L. Entre todos os compostos, SZ-7 demonstrou possuir propriedades de modulação de effluxo na presença de glucose. Para testar esta actividade, estirpes de Salmonella resistentes à ciprofloxacina, induzidas a elevados níveis de resistência com sobre-expressão de BE, foram expostas ao SZ-7. Este derivado afectou a susceptibilidade das estirpes à ciprofloxacina. Uma vez que os 63 compostos estudados apresentaram pouco efeito inibitório /cumulativo, apesar de serem conhecidos pelos seus efeitos moduladores de BE-dependentes de iões em eucariotas, foi questionado o papel dos iões na regulação de BE bacterianas, que poderão influenciar a eficácia de novos compostos. Para este estudo, utilizamos a Escherichia coli AG100 como modelo, devido ao extenso conhecimento no que respeita a estrutura e actividade das BE. Devido à importância de iões de cálcio (Ca2+) nos canais de transporte membranar e na actividade de ATPases, a sua actividade na modulação do efluxo foi investigada. De resultados anteriormente obtidos concluiu-se que a pH 5 o efluxo é independente de energia metabólica; contudo, a pH 8 é absolutamente dependente, sendo que o Ca2+ é indispensável para manter a actividade das ATPases bacterianas. A acumulação/effluxo de EtBr pela E. coli AG100 foi determinada na presença/ausência de Ca2+, clorpromazina (inibidor de ligação de Ca2+ a proteínas), e ácido etilenodiamino tetra-acético (quelante de Ca2+). Acumulação/effluxo aumentou a pH 8, contudo o Ca2+ reverte estes efeitos evidenciando a sua importância no funcionamento das BE bacterianas. Em resumo este trabalho colocou em evidência que muitos aspectos bioquímicos e bioenergéticos devem ser tomados em consideração no estudo da resistência bacteriana mediada por BE.------- ABSTRACT: Sixty-three hydantoin derivatives were evaluated for their modulating effects on efflux pump (EP) activity of Salmonella NCTC 13349 utilizing a semi-automatic fluorometric method. None of the compounds presented antibacterial activities at concentrations as high as 240 mg/L. Among all compounds, SZ-7 showed possible efflux modulating activity in the presence of glucose, indicative of a potential EP inhibitor. To verify its potential effects, ciprofloxacin-resistant Salmonella strains, induced to high level resistance with over-expressing EPs, were exposed to SZ-7. This derivative affected the susceptibility of the ciprofloxacin-resistant strains. Since the 63 compounds studied had very low inhibitory/accumulative effects, even though their known for being efficient in modulating ion-driven eukaryotic EPs, we questioned whether ions had a leading role in regulating bacterial EPs, influencing the effectiveness of new compounds. For this study we used Escherichia coli AG100 as a model, due to the extensive knowledge on its EPs structure and activity. Owing the importance of calcium ions (Ca2+) for membrane transport channels and activity of ATPases, the role of Ca2+ was investigated. From previous results we concluded that at pH 5 efflux is independent of metabolic energy; however, at pH 8 it is entirely dependent of metabolic energy and the Ca2+ ions are essential to maintain the activity of bacterial ATPases. Accumulation and efflux of ethidium bromide (EtBr) by E. coli AG100 was determined in the presence and absence of Ca2+, chlorpromazine (inhibitor of Ca2+-binding to proteins), and ethylenediaminetetraacetic acid (Ca2+ chelator). Accumulation of EtBr increased at pH 8; however Ca2+ reversed these effects providing information as to the importance of this ion in the regulation of bacterial EP systems. Overall this work puts in evidence that many biochemical and bioenergetic aspects related to the strains physiology need to be taken into consideration in bacterial drug resistance mediated by EPs.

Leishmanicidal activity of Echinaster (Othilia) echinophorus crude extract

In this study, a methanolic extract from Echinaster (Othilia) echinophorus was evaluated for activity against Leishmania amazonensis. The extract showed activity against the promastigote and amastigote forms with IC50 values of 62.9 and 37.5 μg.mL-1 respectively. This extract showed a moderate toxicity on macrophages from BALB/c mice. A dose of 100 mg/kg/day was effective when administered during 15 days by intraperitoneal route to BALB/c mice infected experimentally.

Mobilidade funcional, risco de queda, nível de actividade física e percepção de saúde em indivíduos com 65 ou mais anos

RESUMO:O objectivo deste estudo foi analisar a relação entre mobilidade funcional, risco de queda, nível de actividade física e percepção de saúde de 34 indivíduos praticantes (n=18) e não praticantes (n=16) de exercício físico duas ou mais vezes por semana durante pelo menos 45 minutos, residentes na comunidade e ambulatórios. Tipo de estudo: transversal exploratório-descritivo. Metodologia: foi feito um levantamento das variáveis de caracterização (idade, sexo, habilitações literárias, situação sócio-económica, situação familiar) e do estado cognitivo e estado emocional/depressão (Mini-Mental State Examination e Geriatric Depression Scale). As variáveis em análise foram: a mobilidade funcional avaliada através do Timed up and GoTest, o risco de queda medido com o Funtional Reach Test, o nível de actividade física avaliado através do Questionário Internacional de Actividade Física (IPAQ) e a percepção de saúde medida através do SF-6D. Foi também questionada a prática de alguma modalidade de exercício físico, da sua frequência e duração. Os dados foram analisados através de estatística descritiva, foi realizada uma regressão linear múltipla e uma análise bivariada das correlações, utilizando o coeficiente de correlação linear de Pearson (p ≤ 0,05).Resultados: verificou-se que, na amostra global, a maioria dos indivíduos apresentou uma mobilidade funcional considerada normal (TUG<10 segundos), e um risco de queda moderado (FRT entre 15,24 e 25,40 cm), embora sem diferenças entre os grupos em análise. A actividade física apresentou uma duração média de 685,88±540,16 minutos por semana, sendo que 18 indivíduos praticavam exercício físico pelo menos 45 minutos e duas ou mais vezes por semana.A percepção do estado de saúde foi bastante satisfatória, sendo a pontuação média do SF-6D de 0,915±0,067. A análise entre grupos demonstrou que o grupo que praticava exercício físico apresentava um maior número de indivíduos na faixa etária dos 65-74 anos, tinha mais escolarização e melhor estado cognitivo. Estes indivíduos eram fisicamente mais activos e faziam-o, na sua maioria, com uma frequência bissemanal, apenas um desempenhando uma modalidade de intensidade vigorosa. A análise estatística demonstrou que: a mobilidade funcional e o risco de queda eram mais desfavoráveis nos indivíduos com mais idade; o estado cognitivo estava associado a maior mobilidade funcional; uma boa mobilidade funcional correspondeu a um risco de queda reduzido, a mais prática de actividade física, a melhor percepção do estado de saúde e a manutenção do estado cognitivo. Os indivíduos com menor risco de queda apresentaram melhor estado cognitivo e emocional. E este último correspondeu a uma melhor percepção do estado de saúde e a um melhor estado cognitivo. Conclusão: a manutenção da mobilidade funcional reduz o risco de queda aumenta a prática de actividade física e melhora a percepção de saúde de indivíduos com 65 ou mais anos residentes na comunidade.--------- ABSTRACT: Objective: the aim of this study was to analyze the relationship between functional mobility, falls risk, level of physical activity and health perception in a sample of 34 subjects, 18 that practice exercise two or more times a week for at least 45 minutes and 16 that don’t practice exercise, residents and community. Designs: cross-sectional exploratory-descriptive survey. Methods: descriptive variables are age, sex, education, socio-economic level, family status, cognitive status (Mini-Mental State Examination) and emotional status/depression (Geriatric Depression Scale). We analyze the functional mobility with the Timed up and Go Test, the falls risk with Functional Reach Test, the level of physical activity with the International Physical Activity Questionnaire (IPAQ) and health perception with SF-6D. We also questioned the practice of exercise, their frequency and duration. Data were analyzed using descriptive statistics, a multiple linear regression analysis and bivariate correlations, using the linear correlation coefficient of Pearson (p ≤ 0.05). Results: we found that, in the total sample, most individuals had considered a normal functional mobility (TUG <10 seconds), and a moderate falls risk (FRT between 15.24 and 25.40 cm), but no difference between groups. Physical activity showed an mean of 685.88 ± 540.16 minutes per week, with 18 individuals pratice physical exercise at least 45 minutes and two or more times per week. The mean score of the SF-6D was 0.915 ± 0.067 and the perception of health was satisfactory. The analysis between groups showed that the group that practice physical exercise had a greater number of individuals aged 65-74 years, had more schooling and better cognitive status. These subjects were more physically active and mostly did it two times a weak and only one playing a kind of vigorous intensity. The multiple linear regression and correlations, using the linear correlation coefficient of Pearson (p≤0.05) showed that: functional mobility and fall risk decrease with age increase. The cognitive status was associated with greater functional mobility, a good functional mobility corresponded to a reduced falls risk, more physical activity, a better perception of health status and maintenance of cognitive status. Subjects with lower falls risk had better cognitive and emotional state. And subjects with a better emotional status have a better health perception and better cognitive status. Conclusion: the maintenance of functional mobility reduces falls risk, increase physical activity and improves health perception of individuals with 65 years or older living in the community.

In vitro antimalarial activity and cytotoxicity of some selected cuban medicinal plants

Terrestrial plants have been demonstrated to be sources of antimalarial compounds. In Cuba, little is known about antimalarial potentials of plant species used as medicinals. For that reason, we evaluated the antimalarial activity of 14 plant species used in Cuba as antimalarial, antipyretic and/or antiparasitic. Hydroalcoholic extracts were prepared and tested in vitro for the antimalarial activity against Plasmodium falciparum Ghana strain and over human cell line MRC-5 to determine cytotoxicity. Parasite multiplication was determined microscopically by the direct count of Giemsa stained parasites. A colorimetric assay was used to quantify cytotoxicity. Nine extracts showed IC50 values lower than 100 µg/mL against P. falciparum, four extracts were classified as marginally active (SI < 4), one as partially active (Parthenium hysterophorus) exhibiting SI equal to 6.2 and two extracts as active (Bambusa vulgaris and Punica granatum), showing SI > 10. B. vulgaris showed the most potent and specific antiplasmodial action (IC50 = 4.7 µg/mL, SI = 28.9). Phytochemical characterization of active extracts confirmed the presence of triterpenoids in B. vulgaris and polar compounds with phenol free groups and fluorescent metabolites in both extracts as major phytocompounds, by thin layer chromatography. In conclusion, antimalarial use of B. vulgaris and P. hysterophorus was validated. B. vulgaris and P. granatum extracts were selected for follow-up because of their strong antimalarial activity.

Disturbance in hemoglobin metabolism and in vivo antimalarial activity of azole antimycotics

Plasmodium parasites degrade host hemoglobin to obtain free amino acids, essential for protein synthesis. During this event, free toxic heme moieties crystallize spontaneously to produce a non-toxic pigment called hemozoin or ß-hematin. In this context, a group of azole antimycotics, clotrimazole (CTZ), ketoconazole (KTZ) and fluconazole (FCZ), were investigated for their abilities to inhibit ß-hematin synthesis (IßHS) and hemoglobin proteolysis (IHbP) in vitro. The ß-hematin synthesis was recorded by spectrophotometry at 405 nm and the hemoglobin proteolysis was determined by SDS-PAGE 12.5%, followed by densitometric analysis. Compounds were also assayed in vivo in a malaria murine model. CTZ and KTZ exhibited the maximal effects inhibiting both biochemical events, showing inhibition of β-hematin synthesis (IC50 values of 12.4 ± 0.9 µM and 14.4 ± 1.4 µM respectively) and inhibition of hemoglobin proteolysis (80.1 ± 2.0% and 55.3 ± 3.6%, respectively). There is a broad correlation to the in vivo results, especially CTZ, which reduced the parasitemia (%P) of infected-mice at 4th day post-infection significantly compared to non-treated controls (12.4 ± 3.0% compared to 26.6 ± 3.7%, p = 0.014) and prolonged the survival days post-infection. The results indicated that the inhibition of the hemoglobin metabolism by the azole antimycotics could be responsible for their antimalarial effect.

Assessment of physical impairments in leprosy patients: a comparison between the world health organization (who) disability grade and the Eye-Hand-Foot Score

This cross-sectional study assessed the grade of physical impairments in 61 individuals with leprosy receiving multidrug therapy (MDT) under the Brazilian Unified Health System (SUS), and residing in Campina Grande, Paraíba State, Brazil. Impairments were assessed using the disability grade (DG) standardized by the WHO, and the EHF score (Eye-Hand-Foot sum of impairment scores). Impairments were detected in 25 (41%) of the subjects. A total of 14 (23%) patients scored DG 1, while 11 (18%) were assigned DG 2. The EHF score ranged from 1 to 10 points in the group of patients with physical impairments, with a mean score of 3.6 points. The majority of individuals with impairments were affected in at least two sites. We conclude that the EHF score showed overlapping impairments in the segments examined and may be more appropriate than the DG classification system for describing the degree of physical impairment of leprosy patients.

In vitro activity of the clinical pulmonary surfactant Surfacen® against Leishmania amazonensis

Surfacen® is an exogenous natural lung surfactant, composed by phospholipids and hydrophobic proteins, which is applied successfully in Newborn Respiratory Distress Syndrome. In this paper, in vitro activity of Surfacen® against Leishmania amazonensis is described. The product showed activity against the amastigote form found in peritoneal macrophages from BALB/c mice, with an IC50 value of 17.9 ± 3.0 µg/mL; while no toxic effect on host cell was observed up to 200 µg/mL. This is the first report about the antileishmanial activity of Surfacen®.

Induction of phagocytic activity and nitric-oxide production in natural populations of Trypanosoma Cruzi I and II from the state of Paraná, Brazil

Twelve strains of Trypanosoma cruzi isolated from wild reservoirs, triatomines, and chronic chagasic patients in the state of Paraná, southern Brazil, and classified as T. cruzi I and II, were used to test the correlation between genetic and biological diversity. The Phagocytic Index (PI) and nitric-oxide (NO) production in vitro were used as biological parameters. The PI of the T. cruzi I and II strains did not differ significantly, nor did the PI of the T. cruzi strains isolated from humans, triatomines, or wild reservoirs. There was a statistical difference in the inhibition of NO production between T. cruzi I and II and between parasites isolated from humans and the strains isolated from triatomines and wild reservoirs, but there was no correlation between genetics and biology when the strains were analyzed independently of the lineages or hosts from which the strains were isolated. There were significant correlations for Randomly Amplified Polymorphic Deoxyribonucleic acid (RAPD) and biological parameters for T. cruzi I and II, and for humans or wild reservoirs when the lineages or hosts were considered individually.