Etiopathogenic features of severe epistaxis in histological samples from individuals with or without arterial hypertension.

There is a consensus that arterial hypertension (AH) is associated with stroke. Therefore, this study aimed to evaluate the histology of the microvasculature associated with the mucosa of the posterior nasal cavity to identify possible factors related to vascular weakening and rupture. Histological sections were obtained from hypertensive and normotensive individuals, regardless of epistaxis. Our results showed that the group with AH had: (a) smaller median diameter of the lumen of arteries and arterioles; (b) increased thickness of the intimal arteries and arterioles, slight inflammatory infiltrate, and rupture of internal elastic lamina; (c) greater thickness of the middle tunica in arterioles; (d) lower percentage of histological sections with non-injured intimal layers in capillaries, arterioles, and small arteries; (e) lower percentage of histological sections with intact media tunic and/or myocytes juxtaposed in arteries and arterioles; (f) no difference between the diameters of small arteries or arterioles. The intima was thicker in individuals with severe epistaxis than in the normotensive group, but it did not differ from the AH group. Thus, hypertension may cause structural lesions in the vascular layers, and in the absence of tissue repair and the persistence of AH, these lesions may favour vascular rupture, especially during hypertensive peaks.

Methodological variations affect the release of VEGF in vitro and fibrinolysis' time from platelet concentrates.

Blood Concentrates (BCs) are autologous non-transfusional therapeutical preparations with biological properties applied in tissue regeneration. These BCs differ in the preparation method, in fibrin network architecture, growth factors release as well as in platelet/cell content. Methodological changes result in distinct matrices that can compromise their clinical effectiveness. The present study evaluated the influence of different g-forces and types of tubes in the release of vascular endothelial growth factor (VEGF) from platelet-rich fibrin (PRF) as a function of time. The PRF-like samples were obtained with three g-forces (200, 400, and 800 x g) for 10 minutes in pure glass tubes or in polystyrene-clot activator tubes. Scanning and Transmission electron microscopy was used to morphometric analyzes of PRF's specimens and flow cytometry was used to quantify VEGF slow release until 7 days. Our results showed that platelets were intact and adhered to the fibrin network, emitting pseudopods and in degranulation. The fibrin network was rough and twisted with exosomic granulations impregnated on its surface. An increase in the concentration of VEGF in the PRF supernatant was observed until 7 days for all g forces (200, 400 or 800 xg), with the highest concentrations observed with 200 x g, in both tubes, glass or plastic. Morphological analyzes showed a reduction in the diameter of the PRF fibers after 7 days. Our results showed that g-force interferes with the shape of the fibrin network in the PRF, as well as affect the release of VEGF stored into platelets. This finding may be useful in applying PRF to skin lesions, in which the rapid release of growth factors can favor the tissue repair process. Our observations point to a greater clarification on the methodological variations related to obtaining PRF matrices, as they can generate products with different characteristics and degrees of effectiveness in specific applications.

Características moleculares de Staphylococcus aureus susceptível à vancomicina poderia ajudar a prever falhas no tratamento devido a reduzida susceptibilidade à vancomicina / Molecular characteristics of vancomycin-susceptible Staphylococcus aureus could help to predict treatment failure due to reduced vancomycin susceptibility / Características moleculares de Staphylococcus aureus susceptible a la vancomicina podría ayudar a predecir fallas en el tratamiento debido a la reducida susceptibilidad a la vancomicina

Justificativa e Objetivos: Staphylococcus aureus resistente à meticilina (MRSA) é uma das causas mais frequentes de infecções relacionadas à assistência à saúde e comunitárias, e com seu avanço, a vancomicina tornou-se a principal opção terapêutica. Entretanto, o seu uso indiscriminado favoreceu o surgimento de MRSA com reduzida suscetibilidade à vancomicina, comumente associados com falhas no tratamento, bacteremia persistente, hospitalização prolongada e desfechos clínicos adversos. Este estudo avaliou a ocorrência de MRSA com reduzida suscetibilidade à vancomicina e determinou algumas características moleculares em comparação com MRSA suscetível à vancomicina (VS-MRSA). Métodos: Determinação do perfil de suscetibilidade aos antimicrobianos, a concentração inibitória mínima (CIM) e concentração bactericida mínima (CBM) para vancomicina, tolerância à vancomicina, tipagem do SCCmec e agr foram realizadas em um total de 177 MRSA. Posteriormente, foram triados para hVISA por BHIA-3V e BHIA-6V e confirmados com a Análise do Perfil Populacional - Área Abaixo da Curva (PAP-AUC). Resultados: Os fenótipos VT-MRSA e hVISA foram encontrados em 13,6% e 5,1% dos isolados clínicos de MRSA, respectivamente, e a presença de hVISA foi estatisticamente significativa entre os isolados de VT-MRSA (p<0,05). Em VT-MRSA, SCCmec tipo II foi significativamente mais frequente do que em não-VT-MRSA, assim como a presença do agr grupo II. Conclusão: Características moleculares encontradas em MRSA são importantes para a epidemiologia, bem como para demonstrar um padrão em isolados com reduzida suscetibilidade à vancomicina. Testes não-convencionais para detecção destas características podem ser realizados para evitar a identificação errada de VS-MRSA que, consequentemente, resulta em falhas no tratamento com vancomicina.(AU)

Background and Objectives: Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most frequent causes of healthcare-associated and community-acquired infections and with its advancement, vancomycin became the main therapeutic option. However, its indiscriminate use favored the emergence of MRSA with reduced susceptibility to vancomycin, commonly associated with vancomycin treatment failure, persistent bacteremia, prolonged hospitalization and adverse clinical outcome. This study evaluated the occurrence of MRSA with reduced vancomycin susceptibility and determined some molecular characteristics in comparison with vancomycin-susceptible MRSA (VS-MRSA). Methods: Determination of antimicrobial susceptibility profile, the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) for vancomycin, vancomycin-tolerance, SCCmec and agr typing were performed in a total of 177 MRSA. Thereafter, they were screened for hVISA by BHIA-3V and BHIA-6V and confirmed with population analysis profile - area under the curve method (PAP-AUC). Results: VT-MRSA and hVISA phenotypes were found in 13.6% and 5.1% of clinical isolates of MRSA, respectively, and the presence of hVISA was statistically significant among VT-MRSA isolates (p<0.05). In T-MRSA, SCCmec type II was significantly more frequent than in non-VT-MRSA, as well as the presence of agr group II. Conclusion: Molecular characteristics found in MRSA are important for epidemiology, as well as demonstrate a pattern in reduced vancomycin susceptibility isolates. Non-conventional tests for detection of these characteristics might be performed to prevent misidentification of VS-MRSA that, consequently, results in vancomycin treatment failures.(AU)

Justificación y objetivos: Staphylococcus aureus resistente a la meticilina (MRSA) es una de las causas más frecuentes de infecciones relacionadas con la asistencia sanitaria y comunitarias, y con su avance, a la vancomicina se ha convertido en la principal opción terapéutica. Sin embargo, su uso indiscriminado favoreció el surgimiento de MRSA con reducida susceptibilidad a la vancomicina, comúnmente asociados con fallas en el tratamiento, bacteriemia persistente, hospitalización prolongada y resultados clínicos adversos. Este estudio evaluó la ocurrencia de MRSA con reducida susceptibilidad a la vancomicina y determinó algunas características moleculares en comparación con MRSA susceptible a la vancomicina (VS-MRSA). Métodos: Determinación del perfil de susceptibilidad a los antimicrobianos, la concentración inhibitoria mínima (CIM) y la concentración bactericida mínima (CBM) para vancomicina, tolerancia a la vancomicina, tipificación del SCCmec y agr se realizaron en un total de 177 MRSA. Resultados: Los fenotipos VT-MRSA y hVISA se encontraron en el 13,6% y el 5,1% de los aislados clínicos de MRSA, respectivamente, y la presencia de hVISA fue estadísticamente significativa entre los aislados de VT-MRSA (p<0.05). En VT-MRSA, SCCmec tipo II fue significativamente más frecuente que en no-VT-MRSA, así como la presencia del agr grupo II. Conclusión: Características moleculares encontradas en MRSA son importantes para la epidemiología, así como para demostrar un patrón en aislados con reducida susceptibilidad a la vancomicina. Pruebas no convencionales para la detección de estas características pueden realizarse para evitar la identificación errónea de VS-MRSA que, consecuentemente, resulta en fallas en el tratamiento con vancomicina.(AU)

Antimicrobial Resistance Profiles in Enterococcus spp. Isolates From Fecal Samples of Wild and Captive Black Capuchin Monkeys (Sapajus nigritus) in South Brazil.

The environment, human, and animals play an important role in the spread of antibiotic-resistant bacteria. Enterococci are members of the gastrointestinal tracts of humans and animals and represent important reservoirs of antibiotic resistance genes. Until today, few studies have examined antibiotic susceptibility in enterococci isolated from primates. Therefore, the present study investigated species distribution, antibiotic susceptibility, and resistance genes in enterococci isolated from wild and captive black capuchins monkeys (Sapajus nigritus) in Rio Grande do Sul, South Brazil. A total of 24 swabs/fecal samples were collected, including 19 from wild monkeys living in two forest fragments [São Sebastião do Caí (SSC) and Santa Cruz do Sul (SCS)], and five in captive [Parque Zoológico da Fundação Zoobotânica (ZOO)], between August 2016 and November 2017. Fifteen colonies were randomly selected from each sample. Enterococci were identified by MALDI-TOF, tested for susceptibility to 12 antibiotics; and screened for tet(S), tet(M), tet(L), msrC, and erm(B) genes by PCR. Two-hundred ninety-six enterococci were isolated (SSC n = 137; SCS n = 86; ZOO n = 73) and differences in Enterococcus species distribution were detected on three monkey groups, with low abundance in SCS (1 - D = 0.2), followed by ZOO (1 - D = 0.68), and SSC (1 - D = 0.73). The enterococci frequently recovered include the following: Enterococcus faecalis (42.6%), E. hirae (29.1%), and E. faecium (15.9%). Antibiotic-nonsusceptible was observed in 202 (67.9%) strains. The rate of non-susceptibility to rifampicin, tetracycline, erythromycin, nitrofurantoin, chloramphenicol, and ampicillin was 46%, 26%, 22% and 19%, 13%, 0.3%, and 0.3%, respectively. All strains were susceptible to vancomycin, streptomycin, gentamycin, and linezolid. Forty-three (14.52%) isolates were identified as multidrug resistant (MDR), and the highest number of MDR enterococci were E. faecium recovered from wild monkeys living close to a hospital and water treatment plant. Elevated rates of antibiotic resistance genes msrC and tet(L) were isolates from ZOO. In conclusion, differences in the frequency of enterococci species, antibiotic-nonsusceptible and antibiotic resistance genes in all groups of monkeys were identified. These data suggest that anthropogenic activities could have an impact in the resistome of primate gut enterococci communities.

Evaluation of a selective chromogenic medium for detecting vancomycin-resistant enterococci

ABSTRACT Rapid identification of vancomycin-resistant enterococci (VRE) can assist in choosing the appropriate treatment and preventing VRE spread. The performance of chromIDTM VRE agar was evaluated using 184 clinical isolates of Enterococcus spp. and reference strains. The test had a sensitivity of 95.52% but a low specificity of 30%.

Evaluation of a selective chromogenic medium for detecting vancomycin-resistant enterococci.

Rapid identification of vancomycin-resistant enterococci (VRE) can assist in choosing the appropriate treatment and preventing VRE spread. The performance of chromID™ VRE agar was evaluated using 184 clinical isolates of Enterococcus spp. and reference strains. The test had a sensitivity of 95.52% but a low specificity of 30%.

Toxicity and Larvicidal Activity of Podophyllum-Based Lignans Against Aedes aegypti (Diptera: Culicidae).

Aedes aegypti L. (Diptera: Culicidae) is a mosquito species that has adapted to urban environments and is the main vector of dengue viruses. Because of the increasing incidence of dengue, a more environmentally acceptable insecticide needs to be found. Natural products have been and continue to be an important source of leading compounds that can be modified in order to develop new drugs. The lignan family of natural products includes compounds with a diverse spectrum of biological activity. Podophyllotoxin and its related lignans represent an exciting class of natural products that can be targeted at different types of biological activity and are therefore worth exploring further. This study had the aim of evaluating the larvicidal activity of an ethanolic extract from the rhizomes and roots of Podophyllum hexandrum (PM-3) and its isolated lignans, podophyllotoxone (1) and desoxypodophyllotoxin (2), on the larvae of the mosquito vector Ae. aegypti. The PM-3 extract and the compounds (1) and (2) were dissolved in a mixture of acetone and dimethylsulfoxide at final concentrations of 1, 10, 30, 50, 100, and 200 µg/ml. After dilution, the solutions were applied (µg/ml) to the larvae-rearing medium. Overall, the ethanolic extract from the rhizomes and roots of P. hexandrum and the compounds (1) and (2) showed larvicidal activity against the larvae of Ae. aegypti According to the results from this study, it can be concluded that podophyllotoxone (1) and desoxypodophyllotoxin (2) exhibited significant toxicity toward Ae. aegypti larvae.

Production of MMP-9 and inflammatory cytokines by Trypanosoma cruzi-infected macrophages.

Matrix metalloproteinases (MMPs) constitute a large family of Zn(2+) and Ca(2+) dependent endopeptidases implicated in tissue remodeling and chronic inflammation. MMPs also play key roles in the activation of growth factors, chemokines and cytokines produced by many cell types, including lymphocytes, granulocytes, and, in particular, activated macrophages. Their synthesis and secretion appear to be important in a number of physiological processes, including the inflammatory process. Here, we investigated the interaction between human and mouse macrophages with T. cruzi Colombian and Y strains to characterize MMP-9 and cytokine production in this system. Supernatants and total extract of T. cruzi infected human and mouse macrophages were obtained and used to assess MMP-9 profile and inflammatory cytokines. The presence of metalloproteinase activity was determined by zymography, enzyme-linked immunosorbent assay and immunoblotting assays. The effect of cytokines on MMP-9 production in human macrophages was verified by previous incubation of cytokines on these cells in culture, and analyzed by zymography. We detected an increase in MMP-9 production in the culture supernatants of T. cruzi infected human and mouse macrophages. The addition of IL-1ß or TNF-α to human macrophage cultures increased MMP-9 production. In contrast, MMP-9 production was down-modulated when human macrophage cultures were treated with IFN-γ or IL-4 before infection. Human macrophages infected with T. cruzi Y or Colombian strains produced increased levels of MMP-9, which was related to the production of cytokines such as IL-1ß, TNF-α and IL-6.

Burchellin: study of bioactivity against Aedes aegypti.

BACKGROUND: The dengue mosquito Aedes aegypti Linnaeus, 1762 is a widespread insect pest of serious medical importance. Since no effective vaccine is available for treating dengue, the eradication or control of the main mosquito vector is regarded as essential. Since conventional insecticides have limited success, plants may be an alternative source of larvicidal agents, since they contain a rich source of bioactive chemicals. The aim of this study was to evaluate the larvicidal activity of the neolignan burchellin isolated from Ocotea cymbarum (Lauraceae), a plant from the Amazon region, against third instar larvae of A. aegypti. METHODS: Burchellin obtained from O. cymbarum was analyzed. The inhibitory activity against A. aegypti eggs and larvae and histological changes in the digestive system of treated L3 larvae were evaluated. In addition, nitric oxide synthase activity and nitric oxide levels were determined, and cytotoxicity bioassays performed. RESULTS: The data showed that burchellin interfered with the development cycle of the mosquito, where its strongest toxic effect was 100% mortality in larvae (L3) at concentrations ≥ 30 ppm. This compound did not show target cell toxicity in peritoneal macrophages from BALB/c mice, and proved to have molecular stability when dissolved in water. The L3 and L4 larvae treated with the compound showed cellular destruction and disorganization, cell spacing, and vacuolization of epithelial cells in small regions of the midgut. CONCLUSION: The neolignan burchellin proved to be a strong candidate for a natural, safe and stable phytolarvicidal to be used in population control of A. aegypti.

Mycobacterium tuberculosis belonging to family LAM and sublineage RD Rio: common strains in Southern Brazil for over 10 years

A sublineage of Mycobacterium tuberculosis called RD Rio was described in 2007. Although only recently described, this strain may have been present previously in the population, and its identification in clinical isolates will elucidate bacterial transmission dynamics and host-pathogen interactions. This study evaluated the clonal diversity of the RD Rio sublineage in clinical isolates from Rio Grande-RS obtained between 1998 and 2001. Among the 45 samples analyzed by the MIRU-VNTR method, there were six clusters with two samples each and 33 orphan strains with unique pattern. The strains were distributed across several different lineages including LAM (34.04%), X (14.89%), Haarlem (12.77%), UgandaI (10.64%), S (4.26%), NEW-1 (2.13%) and Cameroon (2.13%); 14.89% of the strains matched to multiple lineages. RD Rio strains were present in 28.9% of the samples and 81.25% of the identified strains belonged to the LAM family. The high clonal diversity observed in this study is a constant feature in this region. The RD Rio sublineage has been in Rio Grande-RS since 1998. The continued monitoring of RD Rio in clinical isolates will enhance the understanding of its epidemiological significance.

Mycobacterium tuberculosis belonging to family LAM and sublineage RD(Rio): common strains in Southern Brazil for over 10 years.

A sublineage of Mycobacterium tuberculosis called RD(Rio) was described in 2007. Although only recently described, this strain may have been present previously in the population, and its identification in clinical isolates will elucidate bacterial transmission dynamics and host-pathogen interactions. This study evaluated the clonal diversity of the RD(Rio) sublineage in clinical isolates from Rio Grande-RS obtained between 1998 and 2001. Among the 45 samples analyzed by the MIRU-VNTR method, there were six clusters with two samples each and 33 orphan strains with unique pattern. The strains were distributed across several different lineages including LAM (34.04%), × (14.89%), Haarlem (12.77%), UgandaI (10.64%), S (4.26%), NEW-1 (2.13%) and Cameroon (2.13%); 14.89% of the strains matched to multiple lineages. RD(Rio) strains were present in 28.9% of the samples and 81.25% of the identified strains belonged to the LAM family. The high clonal diversity observed in this study is a constant feature in this region. The RD(Rio) sublineage has been in Rio Grande-RS since 1998. The continued monitoring of RD(Rio) in clinical isolates will enhance the understanding of its epidemiological significance.

Participation of heparin binding proteins from the surface of Leishmania (Viannia) braziliensis promastigotes in the adhesion of parasites to Lutzomyia longipalpis cells (Lulo) in vitro.

BACKGROUND: Leishmania (V.) braziliensis is a causative agent of cutaneous leishmaniasis in Brazil. During the parasite life cycle, the promastigotes adhere to the gut of sandflies, to avoid being eliminated with the dejection. The Lulo cell line, derived from Lutzomyia longipalpis (Diptera: Psychodidae), is a suitable in vitro study model to understand the features of parasite adhesion. Here, we analyze the role of glycosaminoglycans (GAGs) from Lulo cells and proteins from the parasites in this event. METHODS: Flagellar (Ff) and membrane (Mf) fractions from promastigotes were obtained by differential centrifugation and the purity of fractions confirmed by western blot assays, using specific antibodies for cellular compartments. Heparin-binding proteins (HBP) were isolated from both fractions using a HiTrap-Heparin column. In addition, binding of promastigotes to Lulo cells or to a heparin-coated surface was assessed by inhibition assays or surface plasmon resonance (SPR) analysis. RESULTS: The success of promastigotes subcellular fractionation led to the obtainment of Ff and Mf proteins, both of which presented two main protein bands (65.0 and 55.0 kDa) with affinity to heparin. The contribution of HBPs in the adherence of promastigotes to Lulo cells was assessed through competition assays, using HS or the purified HBPs fractions. All tested samples presented a measurable inhibition rate when compared to control adhesion rate (17 ± 2.0% of culture cells with adhered parasites): 30% (for HS 20 µg/ml) and 16% (for HS 10 µg/ml); HBP Mf (35.2% for 10 µg/ml and 25.4% for 20 µg/ml) and HBP Ff (10.0% for 10 µg/ml and 31.4% for 20 µg/ml). Additionally, to verify the presence of sulfated GAGs in Lulo cells surface and intracellular compartment, metabolic labeling with radioactive sulfate was performed, indicating the presence of an HS and chondroitin sulfate in both cell sections. The SPR analysis performed further confirmed the presence of GAGs ligands on L. (V.) braziliensis promastigote surfaces. CONCLUSIONS: The data presented here point to evidences that HBPs present on the surface of L. (V.) braziliensis promastigotes participate in adhesion of these parasites to Lulo cells through HS participation.

Avaliação da atividade e toxicidade de derivados de tiossemicarbazonas e semicarbazonas contra Trypanosoma cruzi e Leishmania (L. ) amazonensis in vitro / Evaluation of the activity and toxicity of thiosemicarbazones and semi-carbazones against Trypanosoma cruzi and Leishmania (L. ) amazonensis in vitro

Os tratamentos disponíveis para a Doença de Chagas e as leishmanioses não são eficientes e apresentam alta toxicidade. Efeito sinérgico tem sido demonstrado, quando drogas referência e novos compostos, são associados e utilizados contra estas patologias. Tiossemicarbazonas (TS) e semicarbazonas (SC) são classes de compostos com importante atividade sobre vários patógenos, incluindo o T. cruzi e a Leishmania sp. Na presente tese foram avaliados in vitro, os efeitos de três derivados de tiossemicarbazonas [estiril-tiosemicarbazona, (2-metoxi-estiril)-tiosemicarbazona e (3-metoxi-4-hidroxi-estiril)-tiosemicarbazona] e de duas semicarbazonas [(2-metoxi-estiril)-semicarbazona e (3-metoxi-4-hidroxi-estiril)-semicarbazona] sobre o T. cruzi e a Leishmania (L.) amazonensis. Nossos resultados revelaram a excelente atividade antiparasitária da maioria dos compostos, sendo que as tiossemicarbazonas mostraram-se mais ativas sobre formas tripomastigotas de T. cruzi em relação as formas promastigotas de L. (L.) amazonensis. Também observamos que a (2-metoxi-esteril)-tiossemicarbazona foi mais efetiva sobre formas amastigotas de T. cruzi, presentes em culturas de macrófagos humanos, em comparação aos parasitos intracelulares alojados em macrófagos peritoneais de camundongos, infectados in vitro. Os ensaios de associação dos compostos as drogas de referência Benzonidazol (BZ) para T. cruzi e Pentamidina (PT) para L. (L) amazonensis), revelaram uma importante potencialização da ação tripanocida e leishmanicida das TS e SC, apresentando baixa toxicidade sobre células de mamíferos. Nossos resultados promissores reforçam a importância da continuidade destes estudos, de modo a identificar terapias mais eficientes para o tratamento das doenças de Chagas e leishmanioses.

Atividade antineoplásica e tripanocida de Hovenia dulcis Thunb. cultivada in vivo e in vitro

Muitas são as substâncias do metabolismo vegetal que têm despertado grande interesse, principalmente no setor de fármacos. No presente estudo, foram avaliadas as atividades antineoplásica e tripanocida de extratos vegetais de Hovenia dulcis (Rhamnaceae) cultivada sob condições in vivo e in vitro. Extratos metanólicos das folhas de material jovem desenvolvido in vivo e in vitro, exibiram altas porcentagens na inibição do crescimento de todas as linhagens de células tumorais testadas, enquanto extratos etanólicos do pseudofruto mostraram seletividade com elevado percentual de inibição do crescimento celular nas linhagens SP2/0 e BW. Quanto à atividade tripanocida, os extratos aquoso do pseudofruto e metanólico das folhas das plantas germinadas in vivo, apresentaram percentual de inibição em 48 h, de 95 por cento e 100 por cento, respectivamente.

Plants produce a wide range of secondary metabolites, many of which are pharmaceutically important. In this paper were evaluated anti-cancer and trypanocidal activities from Hovenia dulcis (Rhamnaceae) in vivo and in vitro propagated plants. Methanolic extracts of young leaves from in vivo and in vitro material were remarkably active for all tumor cells lines tested, while ethanolic extracts of pseudofruit showed high degree of selectivity against to SP2/0 and BW cells in culture. Mortality of 95 and 100 percent (48 h) on Trypanosoma cruzi were observed on the aqueous extract of pseudofruit and methanolic extracts of leaves from seedlings.