Androgen receptor mRNA measured by quantitative real time PCR is decreased in the urethral mucosa of patients with middle idiopathic hypospadias.

Androgen action is exerted through the androgen receptor. The normal 46,XY genital virilization depends on androgen receptor gene expression, which is tissue specific, and requires normal androgen receptor mRNA levels in androgen sensitive tissues. Hypospadias is a frequent male genital abnormality, potentially related to reduced androgen sensitivity in genital tissues. The aim of this study was to compare, by quantitative real time PCR, the amount of androgen receptor mRNA in cells obtained from the urethral mucosa of patients with middle idiopathic hypospadias with the androgen receptor mRNA levels observed in control phimosis subjects with eutopic urethral opening. Prepubertal individuals were studied, including 41 controls and 17 hypospadias patients with mean (SD) ages of 4.7 (2.1) years and 4.0 (3.0) years, respectively. We observed significantly less androgen receptor mRNA in the urethral mucosa of patients with hypospadias than in the controls (p=0.002). The correlation between the level of androgen receptor mRNA expression and the penile size was almost statistically significant only in hypospadias patients (r=0.47; p=0.053). We also established the number of CAG repeats in exon 1 of the androgen receptor gene by GeneScan analysis. No significant difference was observed in the number of CAG repeats when patients and controls were compared. A negative correlation between the CAG repeats and penile size was detected in patients with hypospadias, but not in controls. Our data suggest that a critical lower level of androgen receptor mRNA expression could be a determining factor in the development of middle hypospadias.

Tissue-specific adaptive levels of glucocorticoid receptor alpha mRNA and their relationship with insulin resistance.

Insulin resistance is an underlying cause of metabolic changes associated with cardiovascular diseases. Glucocorticoids are known determinant factors of insulin resistance. We quantified glucocorticoid receptor alpha (GRα) mRNA and 11 beta-hydroxysteroid dehydrogenase type 1 (11ß-HSD1) mRNA in various tissues of 35 patients with previously established cardiovascular disease. This was a prospective study in a cardiac surgery patient setting. Samples of subcutaneous adipose tissue, epicardial fat, muscle, and peripheral blood mononuclear cells were examined. GRα and 11ß-HSD1 mRNA were determined by real-time PCR. Mean age was 54.4 years. A significantly higher level of GRα mRNA was observed in muscle, with mean = 43.6 arbitrary units, median (p25-p75) = 39.4, compared to epicardial adipose tissue, with mean = 34.2, median (p25-p75) = 27.6, and to subcutaneous adipose tissue, with mean = 29.0, median (p25-p75) = 19.0, and lymphocytes, with mean = 17.5, median (p25-p75) = 14.02. When patients with diabetes mellitus were compared to patients without insulin resistance, significantly lower levels of GRα mRNA were observed in epicardial fat. Lymphocytes had the lowest 11ß-HSD1 mRNA concentration. We also observed significantly reduced 11ß-HSD1 mRNA levels in visceral fat when compared with muscle tissue. GRα and 11ß-HSD1 mRNA levels differed among tissues involved in the pathophysiology of metabolic syndrome. We conclude that epicardial adipose tissue has lower GRαmRNA levels in insulin-resistant patients; this seems to be an adaptive and protective mechanism.

Antiproliferative, genotoxic and mutagenic potential of synthetic chocolate food flavoring.

Flavoring additives are of great technological importance for the food industry. However, there is little information regarding the toxicological properties of these micro-ingredients, especially at the cellular level. The present study used meristematic root cells of Allium cepa L. to evaluate the toxicity of a liquid, aroma and flavor synthetic chocolate additive, manufactured and widely marketed throughout Brazil and exported to other countries in South America. The flavoring concentrations evaluated were 100.00; 50.00; 25.00; 1.00; 0.50 and 0.25 µL/L, where the highest concentration established was one-hundred times lower than that commercially suggested for use. The concentration 100 µL/L substantially reduced cell division of meristems within 24- and 48-hours exposure. Concentrations from 100.00 to 0.50 µL/L resulted in a significant number of prophases to the detriment of the other phases of cell division, indicating an aneugenic activity, and induced a significant number of cellular changes, with emphasis on micronuclei, nuclear buds and chromosomal breaks. Under the established analysis conditions, with the exception of concentration 0.25 µL/L, the flavoring of chocolate caused cytotoxicity, genotoxicity and mutagenicity to root meristems.

Biosynthesis and characterization of gold nanoparticles using Brazilian red propolis and evaluation of its antimicrobial and anticancer activities.

Gold nanoparticles (AuNPs) are highlighted due to their low toxicity, compatibility with the human body, high surface area to volume ratio, and surfaces that can be easily modified with ligands. Biosynthesis of AuNPs using plant extract is considered a simple, low-cost, and eco-friendly approach. Brazilian Red Propolis (BRP), a product of bees, exhibits anti-inflammatory, anti-tumor, antioxidant, and antimicrobial activities. Here, we described the biosynthesis of AuNPs using BRP extract (AuNPextract) and its fractions (AuNPhexane, AuNPdichloromethane, AuNPethyl acetate) and evaluated their structural properties and their potential against microorganisms and cancer cells. AuNPs showed a surface plasmon resonance (SPR) band at 535 nm. The sizes and morphologies were influenced by the BRP sample used in the reaction. FTIR and TGA revealed the involvement of bioactive compounds from BRP extract or its fractions in the synthesis and stabilization of AuNPs. AuNPdichloromethane and AuNPhexane exhibited antimicrobial activities against all strains tested, showing their efficacy as antimicrobial agents to treat infectious diseases. AuNPs showed dose-dependent cytotoxic activity both in T24 and PC-3 cells. AuNPdichloromethane and AuNPextract exhibited the highest in vitro cytotoxic effect. Also, the cytotoxicity of biogenic nanoparticles was induced by mechanisms associated with apoptosis. The results highlight a potential low-cost green method using Brazilian red propolis to synthesize AuNPs, which demonstrated significant biological properties.

Metallothionein and p-Akt proteins in oral dysplasia and in oral squamous cell carcinoma: an immunohistochemical study.

BACKGROUND: Oral leukoplakia (OL) is the main potentially malignant lesion of the oral cavity, and oral squamous cell carcinoma (OSCC) accounts for more than 95% of all malignant neoplasms in the oral cavity. Therefore, the aim of this study was to verify the immunoexpression of p-Akt and Metallothionein (MT) proteins in dysplasic and neoplasic oral lesions. METHODS: Immunohistochemical studies were carried out on 10 normal epithelium, 30 OL and 15 OSCC paraffin-embedded samples. Immunoperoxidase reaction for p-Akt and MT proteins was applied on the specimens, and the positivity of the reactions was calculated for 1000 epithelial cells. RESULTS: Using the ANOVA and the Tukey's post hoc statistical analyses, it was observed a significant difference in the immunoexpression for p-Akt and MT when the OSCC samples were compared with normal and dysplasic epithelial groups. In addition, the Pearson's correlation test showed a significant correlation between the proteins' expression. CONCLUSION: Based on the data obtained, p-Akt and MT activation may play an important role in the conversion of a potentially malignant oral lesion to a malignant carcinoma since its earlier stages.

Breast cancer patients with micrometastases in sentinel lymph nodes: differences considering additional metastatic lymph nodes.

AIMS: Characterization of breast cancer patients with micrometastases in sentinel lymph node (SLN) and establish differences between micrometastatic breast cancers with additional metastatic lymph nodes (LNS) versus no other lymph node invasion. METHODS: Analysis of 30 breast cancers, N1mi or pN0(i+), diagnosed and treated in our department from July 2000 to July 2008. RESULTS: Micrometastases in SLNs were found in 30 patients. Complete axillary dissection revealed other metastatic LNs in 24%. Concerning breast cancers with additional LN invasion versus no other LN invasion, tumors located in the superior-external quadrant were more frequent in the former group. Other characteristics as clinical presentation, histological subtype, focality, cytonuclear grade, hormone receptors and Her2 expression were not significantly different in either group. Regarding SLN invasion, the presence of at least two micrometastatic foci were significantly more relevant in patients with other metastatic LN invasion (p < 0.01). Micrometastases diagnosed only after immunohistochemistry (IHC) were exclusively found in patients without other LN invasion, reaching statistical significance (p < 0.05). CONCLUSIONS: Complete axillary dissection revealed additional LN invasion in 24% of patients with micrometastases in the SLN. Tumors with additional LN invasion were more frequently found in the superior external quadrant and SLNs harbored at least two micrometastatic foci. Micrometastases diagnosed exclusively by IHC techniques were more relevant in cases without additional lymph node invasion.

Antibacterial and antiproliferative activities of the fresh leaf essential oil of Psidium guajava L. (Myrtaceae).

This study evaluated the antibacterial and antiproliferative activities of the essential oil of Psidium guajava leaves (PG-EO), traditionally used in folk medicine. The essential oil was obtained from fresh leaves by hydrodistillation, using a modified Clevenger apparatus. The major PG-EO chemical constituents were identified by GC-MS and GC-FID as being ß-caryophyllene (16.1%), α-humulene (11.9%), aromadendrene oxide (14.7%), δ-selinene (13.6%), and selin-11-en-4α-ol (12.5%). The antibacterial activity of the essential oil of P. guajava leaves was determined in terms of its minimum inhibitory concentrations (MIC) using the broth microdilution method in 96-well microplates. PG-EO had moderate activity against Streptococcus mutans (MIC = 200 µg/mL), S. mitis (MIC = 200 µg/mL), S. sanguinis (MIC = 400 µg/mL), S. sobrinus (MIC = 100 µg/mL), and S. salivarius (MIC = 200 µg/mL). The antiproliferative activity was evaluated against different tumor cell lines: breast adenocarcinoma (MCF-7), human cervical adenocarcinoma (HeLa), and human gliobastoma (M059J). A normal human cell line (GM07492A, lung fibroblasts) was included. The antiproliferative activity was evaluated using the XTT assay and the results were expressed as IC50. The essential oil showed significantly lower IC50 values against MCF-7 and M059J lines than that obtained for the normal line, showing selectivity. Our results suggest that the essential oil of Psidium guajava L. has promising biological activities and can be considered a new source of bioactive compounds.

Hunting for Wasps In-between: the Use of the Winkler Extractor to Sample Leaf Litter Hymenoptera.

Soil ecosystems are considered biodiversity hotspots. Most of terrestrial organisms depend almost exclusively on soils at least during some part of their life cycle. Although there is an intensive effort to understand the dynamics involving communities of soil animals, most groups are unappreciated in faunal inventories, such as some parasitic Hymenoptera with soil or litter hosts (SLH Hymenoptera), which are considered one of the largest and most diverse groups of soil- or litter-dwelling animals. Contrasting with flight interception traps, techniques that sample soil and litter specimens normally present low costs and easy transportation, being easily replicated within a site. Among them, the Winkler extractor is a useful technique to sample cryptic species associated with leaf litter. The aim of the present work was to describe the SLH Hymenoptera fauna collected in a pool of samples, using a technique to sample leaf litter arthropods. In this work, we report a total of 600 specimens belonging to Hymenoptera (excluding ants), belonging to 15 families distributed within 24 subfamilies, in samples of leaf litter obtained using the Winkler extractor. We observed that this technique is promising for sampling SLH Hymenoptera and should be considered as a complement for inventories of the Hymenoptera fauna.

Antiproliferative, genotoxic and mutagenic potential of synthetic chocolate food flavoring / Potencial antiproliferativo, genotóxico e mutagênico do aroma de chocolate sintético para alimentos

Flavoring additives are of great technological importance for the food industry. However, there is little information regarding the toxicological properties of these micro-ingredients, especially at the cellular level. The present study used meristematic root cells of Allium cepa L. to evaluate the toxicity of a liquid, aroma and flavor synthetic chocolate additive, manufactured and widely marketed throughout Brazil and exported to other countries in South America. The flavoring concentrations evaluated were 100.00; 50.00; 25.00; 1.00; 0.50 and 0.25 µL/L, where the highest concentration established was one-hundred times lower than that commercially suggested for use. The concentration 100 µL/L substantially reduced cell division of meristems within 24- and 48-hours exposure. Concentrations from 100.00 to 0.50 µL/L resulted in a significant number of prophases to the detriment of the other phases of cell division, indicating an aneugenic activity, and induced a significant number of cellular changes, with emphasis on micronuclei, nuclear buds and chromosomal breaks. Under the established analysis conditions, with the exception of concentration 0.25 µL/L, the flavoring of chocolate caused cytotoxicity, genotoxicity and mutagenicity to root meristems.

Os aditivos aromatizantes têm grande importância tecnológica para a indústria de alimentos. Contudo, poucas são as informações quanto as propriedades toxicológicas desses microingredientes, especialmente, em nível celular. No presente estudo avaliou-se, sobre as células meristemáticas de raízes de Allium cepa L., a toxicidade de um aditivo sintético líquido de aroma e sabor de chocolate, fabricado e amplamente comercializado em todo Brasil, e exportado para outros países da América do Sul. As concentrações de aromatizante avaliadas foram 100,00; 50,00; 25,00; 1,00; 0,50 e 0,25 µL/L, onde a maior concentração estabelecida foi cem vezes menor que a sugerida comercialmente para uso. Com base na interpretação dos resultados, a concentração 100 µL/L reduziu substancialmente a divisão celular dos meristemas nas 24 e 48 horas de exposição. As concentrações 100,00 a 0,50 µL/L demonstraram número significativo de prófases em detrimento as outras fases da divisão celular, indicando ação aneugênica, e induziram número significativo de alterações celulares, com ênfase a micronúcleos, broto nucleares e quebras cromossômicas. Nas condições de análises estabelecidas, com exceção a concentração 0,25 µL/L, o aromatizante de chocolate causou citotoxicidade, genotoxicidade e mutagenicidade aos meristemas radiculares.

Antiproliferative, genotoxic and mutagenic potential of synthetic chocolate food flavoring

Abstract Flavoring additives are of great technological importance for the food industry. However, there is little information regarding the toxicological properties of these micro-ingredients, especially at the cellular level. The present study used meristematic root cells of Allium cepa L. to evaluate the toxicity of a liquid, aroma and flavor synthetic chocolate additive, manufactured and widely marketed throughout Brazil and exported to other countries in South America. The flavoring concentrations evaluated were 100.00; 50.00; 25.00; 1.00; 0.50 and 0.25 µL/L, where the highest concentration established was one-hundred times lower than that commercially suggested for use. The concentration 100 µL/L substantially reduced cell division of meristems within 24- and 48-hours exposure. Concentrations from 100.00 to 0.50 µL/L resulted in a significant number of prophases to the detriment of the other phases of cell division, indicating an aneugenic activity, and induced a significant number of cellular changes, with emphasis on micronuclei, nuclear buds and chromosomal breaks. Under the established analysis conditions, with the exception of concentration 0.25 µL/L, the flavoring of chocolate caused cytotoxicity, genotoxicity and mutagenicity to root meristems.

Resumo Os aditivos aromatizantes têm grande importância tecnológica para a indústria de alimentos. Contudo, poucas são as informações quanto as propriedades toxicológicas desses microingredientes, especialmente, em nível celular. No presente estudo avaliou-se, sobre as células meristemáticas de raízes de Allium cepa L., a toxicidade de um aditivo sintético líquido de aroma e sabor de chocolate, fabricado e amplamente comercializado em todo Brasil, e exportado para outros países da América do Sul. As concentrações de aromatizante avaliadas foram 100,00; 50,00; 25,00; 1,00; 0,50 e 0,25 µL/L, onde a maior concentração estabelecida foi cem vezes menor que a sugerida comercialmente para uso. Com base na interpretação dos resultados, a concentração 100 µL/L reduziu substancialmente a divisão celular dos meristemas nas 24 e 48 horas de exposição. As concentrações 100,00 a 0,50 µL/L demonstraram número significativo de prófases em detrimento as outras fases da divisão celular, indicando ação aneugênica, e induziram número significativo de alterações celulares, com ênfase a micronúcleos, broto nucleares e quebras cromossômicas. Nas condições de análises estabelecidas, com exceção a concentração 0,25 µL/L, o aromatizante de chocolate causou citotoxicidade, genotoxicidade e mutagenicidade aos meristemas radiculares.

Antiproliferative, genotoxic and mutagenic potential of synthetic chocolate food flavoring / Potencial antiproliferativo, genotóxico e mutagênico do aroma de chocolate sintético para alimentos

Flavoring additives are of great technological importance for the food industry. However, there is little information regarding the toxicological properties of these micro-ingredients, especially at the cellular level. The present study used meristematic root cells of Allium cepa L. to evaluate the toxicity of a liquid, aroma and flavor synthetic chocolate additive, manufactured and widely marketed throughout Brazil and exported to other countries in South America. The flavoring concentrations evaluated were 100.00; 50.00; 25.00; 1.00; 0.50 and 0.25 µL/L, where the highest concentration established was one-hundred times lower than that commercially suggested for use. The concentration 100 µL/L substantially reduced cell division of meristems within 24- and 48-hours exposure. Concentrations from 100.00 to 0.50 µL/L resulted in a significant number of prophases to the detriment of the other phases of cell division, indicating an aneugenic activity, and induced a significant number of cellular changes, with emphasis on micronuclei, nuclear buds and chromosomal breaks. Under the established analysis conditions, with the exception of concentration 0.25 µL/L, the flavoring of chocolate caused cytotoxicity, genotoxicity and mutagenicity to root meristems.

Os aditivos aromatizantes têm grande importância tecnológica para a indústria de alimentos. Contudo, poucas são as informações quanto as propriedades toxicológicas desses microingredientes, especialmente, em nível celular. No presente estudo avaliou-se, sobre as células meristemáticas de raízes de Allium cepa L., a toxicidade de um aditivo sintético líquido de aroma e sabor de chocolate, fabricado e amplamente comercializado em todo Brasil, e exportado para outros países da América do Sul. As concentrações de aromatizante avaliadas foram 100,00; 50,00; 25,00; 1,00; 0,50 e 0,25 µL/L, onde a maior concentração estabelecida foi cem vezes menor que a sugerida comercialmente para uso. Com base na interpretação dos resultados, a concentração 100 µL/L reduziu substancialmente a divisão celular dos meristemas nas 24 e 48 horas de exposição. As concentrações 100,00 a 0,50 µL/L demonstraram número significativo de prófases em detrimento as outras fases da divisão celular, indicando ação aneugênica, e induziram número significativo de alterações celulares, com ênfase a micronúcleos, broto nucleares e quebras cromossômicas. Nas condições de análises estabelecidas, com exceção a concentração 0,25 µL/L, o aromatizante de chocolate causou citotoxicidade, genotoxicidade e mutagenicidade aos meristemas radiculares.

A species-level association in Pheidole Westwood (Hymenoptera: Formicidae) ants with a parasitoid wasp of the genus Orasema Cameron (Hymenoptera: Eucharitidae) in Brazil

Abstract Eucharitid wasps are exclusive parasitoids of ants and certain groups of eucharitids have specific associations with their hosts. This type of specificity is widely documented in more inclusive groups (subfamilies and/or genus-groups). However, we do not know if this specificity occurs in less inclusive groups (such as species or populations) or if it is more strongly influenced by local and/or regional environmental constraints. We provide a new association record between Pheidole gibba Mayr, 1887 and Orasema chunpi Burks, Heraty & Dominguez, 2018, while expanding their known distribution to the Brazilian state of Bahia.

Seasonal variation in the biomass and agar yield from Gracilaria cervicornis and Hydropuntia cornea from Brazil.

Seasonality of biomass and agar yield from two agarophytes (G. cervicornis and H. cornea) was determined. The biomass from G. cervicornis was higher (390 g m-2) during the dry season and lower during the rainy season (129 g m-2). The data analysis for G. cervicornis revealed a significant seasonal variation (P < 0.05). H. cornea did not show a clear seasonal variation and was present only from March to August. The peak in biomass for this species was recorded in April (383 g m-2) and was significantly different from the other months (P < 0.05). The agar yield for G. cervicornis varied from 11% to 20%, with generally higher values recorded during the dry season. The agar yield showed a highly significant variation (P < 0.001). Agar yield from H. cornea ranged from 29% to 41%, with a peak recorded in June. The results above indicate that H. cornea can be considered a good candidate for commercial use.

[Primary lymphoma of the lung]. / Linfomas primários do pulmão.

Primary lymphomas of the lung are rare neoplasias that can be easily diagnosed when enough tissue is available, but are easily mistaken for lung carcinomas or mesotheliomas on clinical evaluation. Two surgical cases are described with reference made to their morphological and immunohistochemical characteristics.

[A lymphoepithelioma-like type of spinous-cell carcinoma of the cervix uteri]. / Carcinoma espinho-celular do colo do útero tipo linfoepitelioma-like.

Lymphoepithelioma-like carcinomas of the cervix uteri are very rare. They are poorly differentiated squamous cell carcinomas with intense stromal lymphocytic infiltration. These histologic features are similar to nasopharyngeal lymphoepithelioma and may have a better prognosis than other tumors of the cervix. A lymphoepithelioma-like lesion of the cervix uteri is described in a 33-year-old Caucasian woman who had an episode of vaginal bleeding. A review of the literature about these types of tumor is also presented.

Further Ergatoid Gyne Records in the Ant Tribe Dacetini (Formicidae: Myrmicinae).

Variants of gynes and workers occur in a substantial number of ant species; however, dacetine ergatoid gynes have been recorded just once in the literature thus far. In the present paper, we provide abridged descriptions of five ergatoid female reproductives in five species of Neotropical dacetines belonging to two genera: Acanthognathus brevicornis Smith, Acanthognathus ocellatus Mayr, Acanthognathus rudis Brown & Kempf, Strumigenys cosmostela Kempf, and Strumigenys hindenburgi Forel. We also compare the ergatoids with conspecific gynes and workers.

Antibacterial and antiproliferative activities of the fresh leaf essential oil of Psidium guajava L. (Myrtaceae) / Atividades antibacteriana e antiproliferativa do óleo essencial das folhas frescas de Psidium guajava L. (Myrtaceae)

Abstract This study evaluated the antibacterial and antiproliferative activities of the essential oil of Psidium guajava leaves (PG-EO), traditionally used in folk medicine. The essential oil was obtained from fresh leaves by hydrodistillation, using a modified Clevenger apparatus. The major PG-EO chemical constituents were identified by GC-MS and GC-FID as being β-caryophyllene (16.1%), α-humulene (11.9%), aromadendrene oxide (14.7%), δ-selinene (13.6%), and selin-11-en-4α-ol (12.5%). The antibacterial activity of the essential oil of P. guajava leaves was determined in terms of its minimum inhibitory concentrations (MIC) using the broth microdilution method in 96-well microplates. PG-EO had moderate activity against Streptococcus mutans (MIC = 200 µg/mL), S. mitis (MIC = 200 µg/mL), S. sanguinis (MIC = 400 µg/mL), S. sobrinus (MIC = 100 µg/mL), and S. salivarius (MIC = 200 µg/mL). The antiproliferative activity was evaluated against different tumor cell lines: breast adenocarcinoma (MCF-7), human cervical adenocarcinoma (HeLa), and human gliobastoma (M059J). A normal human cell line (GM07492A, lung fibroblasts) was included. The antiproliferative activity was evaluated using the XTT assay and the results were expressed as IC50. The essential oil showed significantly lower IC50 values against MCF-7 and M059J lines than that obtained for the normal line, showing selectivity. Our results suggest that the essential oil of Psidium guajava L. has promising biological activities and can be considered a new source of bioactive compounds.

Resumo Este estudo avaliou as atividades antibacteriana e antiproliferativa do óleo essencial das folhas frescas de Psidium guajava (PG-OE), tradicionalmente utilizadas na medicina popular. O óleo essencial foi obtido por hidrodestilação das folhas frescas, utilizando aparelho do tipo Clevenger. Os principais constituintes químicos de PG-OE identificados por CG-EM e CG-DIC foram: β-cariofileno (16,1%), α-humuleno (11,9%), óxido de aromadendreno (14,7%), δ-selineno (13,6%) e selin-11-en-4α-ol (12,5%). A atividade antibacteriana do óleo essencial das folhas de P. guajava foi determinada em termo de sua concentração inibitória mínima (CIM) utilizando o método de microdiluição de caldo em microplacas de 96 poços. PG-OE apresentou moderada atividade contra Streptococcus mutans (CIM = 200 μg/mL), S. mitis (CIM = 200 μg/mL), S. sanguinis (CIM = 400 μg/mL), S. sobrinus (CIM = 100 μg/mL) e S. salivarius (CIM = 200 μg/mL). A atividade antiproliferativa foi avaliada frente a diferentes linhagens de células tumorais como: adenocarcinoma de mama (MCF-7), adenocarcinoma cervical humano (HeLa) e gliobastoma humano (M059J). Foi incluída uma linhagem celular humana normal (GM07492A, fibroblastos pulmonares). A atividade antiproliferativa foi avaliada utilizando o ensaio XTT e os resultados foram expressos como CI50. As linhagens MCF-7 e M059J mostraram valores significativamente mais baixos de CI50 do que os obtidos para a linhagem normal, mostrando seletividade. Nossos resultados sugerem que o óleo essencial das folhas frescas de Psidium guajava L. possui atividades biológicas promissoras e pode ser considerado como uma nova fonte de compostos bioativos.

Distribution of the stx1 and stx2 genes in Escherichia coli isolated from milk cattle according to season, age, and production scale in southwestern region of Goiás, Brazil / Distribuição dos genes stx1 e stx2 em Escherichia coli isoladas de bovinos de leite de acordo com a estação, idade e escala de produção na região sudoeste de Goiás, Brasil

This study determined the distribution of stx1 and stx2 genes in Escherichia coli isolated from dairy herds with regard to animal age, season, and farm production-scale, and analyzed the phylogenetic distribution of the groups A, B1, B2, and D of 276 isolates of bovine feces Shiga toxin-producing E. coli (STEC). The stx1 profile was the most common, detected in 20.4% (202/990) of the isolates, followed by stx2 (4.54%, 45/990) and stx1+stx2 (2.92%, 29/990). The stx1 gene was detected more frequently in calves than in adult animals. In the dry season (winter), the presence of stx1+stx2 profile in cattle feces was higher than in the rainy season (summer), while no significant changes were observed between seasons for the stx1 and stx2 profiles. The most predominant phylogenetic groups in adult animals were B1, A, and D, while groups A and B1 prevailed in calves. Our data highlight the importance of identifying STEC reservoirs, since 7.5% of the tested isolates were positive for stx2, the main profile responsible for the hemolytic-uremic syndrome (HUS). Moreover, these microorganisms are adapted to survive even in hostile environments and can contaminate the food production chain, posing a significant risk to consumers of animal products.(AU)

Esse estudo determinou a distribuição dos genes stx1 e stx2 em Escherichia coli isolados de rebanhos leiteiros em relação a idade, estação e produção, e analisaram a distribuição filogenética dos grupos A, B1, B2 e D de 276 E. coli produtoras de toxina Shiga (STEC). O perfil stx1 foi mais comum, detectado em 20,4% (202/990) dos isolados, seguido de stx2 (4,54%, 45/990) e stx1+stx2 (2,92%, 29/990). O gene stx1 foi detectado mais frequentemente em bezerros que animais adultos. No período de seca (inverno), a presença do perfil stx1+stx2 nas fezes dos bovinos foi mais prevalente que no período chuvoso (verão), apesar de não haver diferença significativa entre estações para os perfis stx1 e stx2. Os grupos filogenéticos mais predominantes em animais adultos foram B1, A e D, enquanto grupos A e B2 prevaleceram em bezerros. Nossos dados enfatizam a importância de se detectar reservatórios de STEC já que 7,5% dos isolados testados foram positivos para stx2, o perfil mais prevalente em casos de síndrome hemolítica-urêmica. Ademais, esses microorganismos são adaptados à sobreviver em ambientes hostis e contaminam a cadeia alimentar, levando a risco significativo para consumidores de alimentos de origem animal.(AU)

Antibacterial and antiproliferative activities of the fresh leaf essential oil of Psidium guajava L. (Myrtaceae)

Abstract This study evaluated the antibacterial and antiproliferative activities of the essential oil of Psidium guajava leaves (PG-EO), traditionally used in folk medicine. The essential oil was obtained from fresh leaves by hydrodistillation, using a modified Clevenger apparatus. The major PG-EO chemical constituents were identified by GC-MS and GC-FID as being -caryophyllene (16.1%), -humulene (11.9%), aromadendrene oxide (14.7%), -selinene (13.6%), and selin-11-en-4-ol (12.5%). The antibacterial activity of the essential oil of P. guajava leaves was determined in terms of its minimum inhibitory concentrations (MIC) using the broth microdilution method in 96-well microplates. PG-EO had moderate activity against Streptococcus mutans (MIC = 200 µg/mL), S. mitis (MIC = 200 µg/mL), S. sanguinis (MIC = 400 µg/mL), S. sobrinus (MIC = 100 µg/mL), and S. salivarius (MIC = 200 µg/mL). The antiproliferative activity was evaluated against different tumor cell lines: breast adenocarcinoma (MCF-7), human cervical adenocarcinoma (HeLa), and human gliobastoma (M059J). A normal human cell line (GM07492A, lung fibroblasts) was included. The antiproliferative activity was evaluated using the XTT assay and the results were expressed as IC50. The essential oil showed significantly lower IC50 values against MCF-7 and M059J lines than that obtained for the normal line, showing selectivity. Our results suggest that the essential oil of Psidium guajava L. has promising biological activities and can be considered a new source of bioactive compounds.

Resumo Este estudo avaliou as atividades antibacteriana e antiproliferativa do óleo essencial das folhas frescas de Psidium guajava (PG-OE), tradicionalmente utilizadas na medicina popular. O óleo essencial foi obtido por hidrodestilação das folhas frescas, utilizando aparelho do tipo Clevenger. Os principais constituintes químicos de PG-OE identificados por CG-EM e CG-DIC foram: -cariofileno (16,1%), -humuleno (11,9%), óxido de aromadendreno (14,7%), -selineno (13,6%) e selin-11-en-4-ol (12,5%). A atividade antibacteriana do óleo essencial das folhas de P. guajava foi determinada em termo de sua concentração inibitória mínima (CIM) utilizando o método de microdiluição de caldo em microplacas de 96 poços. PG-OE apresentou moderada atividade contra Streptococcus mutans (CIM = 200 g/mL), S. mitis (CIM = 200 g/mL), S. sanguinis (CIM = 400 g/mL), S. sobrinus (CIM = 100 g/mL) e S. salivarius (CIM = 200 g/mL). A atividade antiproliferativa foi avaliada frente a diferentes linhagens de células tumorais como: adenocarcinoma de mama (MCF-7), adenocarcinoma cervical humano (HeLa) e gliobastoma humano (M059J). Foi incluída uma linhagem celular humana normal (GM07492A, fibroblastos pulmonares). A atividade antiproliferativa foi avaliada utilizando o ensaio XTT e os resultados foram expressos como CI50. As linhagens MCF-7 e M059J mostraram valores significativamente mais baixos de CI50 do que os obtidos para a linhagem normal, mostrando seletividade. Nossos resultados sugerem que o óleo essencial das folhas frescas de Psidium guajava L. possui atividades biológicas promissoras e pode ser considerado como uma nova fonte de compostos bioativos.