Brazilian fruit pulps as functional foods and additives: Evaluation of bioactive compounds

Eight tropical fruit pulps from Brazil were simultaneously characterised in terms of their antioxidant and antimicrobial properties. Antioxidant activity was screened by DPPH radical scavenging activity (126–3987 mg TE/100 g DW) and ferric reduction activity power (368–20819 mg AAE/100 g DW), and complemented with total phenolic content (329–12466 mg GAE/100 g DW) and total flavonoid content measurements (46–672 mg EE /100 g DW), whereas antimicrobial activity was tested against the most frequently found food pathogens. Acerola and açaí presented the highest values for the antioxidant-related measurements. Direct correlations between these measurements could be observed for some of the fruits. Tamarind exhibited the broadest antimicrobial potential, having revealed growth inhibition of Pseudomonas aeruginosa. Escherichia coli, Listeria monocytogenes, Salmonella sp. and Staphylococcus aureus. Açaí and tamarind extracts presented an inverse relationship between antibacterial and antioxidant activities, and therefore, the antibacterial activity cannot be attributed (only) to phenolic compounds.

Characterization and Biological Activities of Ocellatin Peptides from the Skin Secretion of the Frog Leptodactylus pustulatus

Eight new peptides were isolated from the skin secretion of the frog Leptodactylus pustulatus and their amino acid sequences determined by de novo sequencing and by cDNA cloning. Structural similarities between them and other antimicrobial peptides from the skin secretion of Leptodactylus genus frogs were found. Ocellatins-PT1 to -PT5 (25 amino acid residues) are amidated at the C-terminus, while ocellatins-PT6 to -PT8 (32 amino acid residues) have free carboxylates. Antimicrobial activity, hemolytic tests, and cytotoxicity against a murine fibroblast cell line were investigated. All peptides, except for ocellatin-PT2, have antimicrobial activity against at least one Gram negative strain. Ocellatin-PT8 inhibited the growth of Escherichia coli, Staphylococcus aureus, Klebsiella pneumoniae, and Salmonella choleraesuis strains with MICs in the 60−240 μM range. No significant effect was observed in human erythrocytes and in a murine fibroblast cell line after exposure to the peptides at MICs. A comparison between sequences obtained by both direct HPLC-MS de novo sequencing and cDNA cloning demonstrates the secretion of mature peptides derived from a pre-pro-peptide structure.

Heparinized nanohydroxyapatite/collagen granules for controlled release of vancomycin

The purpose of this study was to develop a bone substitute material capable of preventing or treating osteomyelitis through a sustainable release of vancomycin and simultaneously inducing bone regeneration. Porous heparinized nanohydroxyapatite (nanoHA)/collagen granules were characterized using scanning electron microscopy, micro-computed tomography and attenuated total reflectance Fourier transform infrared spectroscopy. After vancomycin adsorption onto the granules, its releasing profile was studied by UV molecular absorption spectroscopy. The heparinized granules presented a more sustainable release over time, in comparison with nonheparinized nanoHA and nanoHA/collagen granules. Vancomycin was released for 360 h and proved to be bioactive until 216 h. Staphylococcus aureus adhesion was higher on granules containing collagen, guiding the bacteria to the material with antibiotic, improving their eradication. Moreover, cytotoxicity of the released vancomycin was assessed using osteoblast cultures, and after 14 days of culture in the presence of vancomycin, cells were able to remain viable, increasing their metabolic activity and colonizing the granules, as observed by scanning electron microscopy and confocal laser scanning microscopy. These findings suggest that heparinized nanoHA/collagen granules are a promising material to improve the treatment of osteomyelitis, as they are capable of releasing vancomycin, eliminating the bacteria, and presented morphological and chemical characteristics to induce bone regeneration.

Antibacterial activity of GUAVA, Psidium guajava Linnaeus, leaf extracts on diarrhea-causing enteric bacteria isolated from Seabob shrimp, Xiphopenaeus kroyeri (Heller)

Guava leaf tea of Psidium guajava Linnaeus is commonly used as a medicine against gastroenteritis and child diarrhea by those who cannot afford or do not have access to antibiotics. This study screened the antimicrobial effect of essential oils and methanol, hexane, ethyl acetate extracts from guava leaves. The extracts were tested against diarrhea-causing bacteria: Staphylococcus aureus, Salmonella spp. and Escherichia coli. Strains that were screened included isolates from seabob shrimp, Xiphopenaeus kroyeri (Heller) and laboratory-type strains. Of the bacteria tested, Staphylococcus aureus strains were most inhibited by the extracts. The methanol extract showed greatest bacterial inhibition. No statistically significant differences were observed between the tested extract concentrations and their effect. The essential oil extract showed inhibitory activity against S. aureus and Salmonella spp. The strains isolated from the shrimp showed some resistance to commercially available antibiotics. These data support the use of guava leaf-made medicines in diarrhea cases where access to commercial antibiotics is restricted. In conclusion, guava leaf extracts and essential oil are very active against S. aureus, thus making up important potential sources of new antimicrobial compounds.

Influenza virus and proteolytic bacteria co-infection in respiratory tract from individuals presenting respiratory manifestations

A role for proteolytic bacteria in the exacerbation of influenza virus has been shown in natural hosts such as pigs and humans. Four hundred seven samples were collected from the respiratory tract of individuals presenting clinical manifestations, during influenza season (2003-2005) in São Paulo City. The aim of this study was to evaluate the incidence of determined bacteria co-infecting virus in human respiratory tract. Tests, such as bacteriological, immunofluorescence (IF), RT/PCR and hemagglutination (HA) were used for bacterial and viral investigation. Thirty seven (9.09%) positive for influenza virus were screened by IF. The RT/PCR confirmed the presence of influenza virus in these samples. Bacterial and agar casein tests demonstrated that 18 (48.64%) individuals were infected with proteolytic bacteria such as Staphylococcus spp., Streptococcus spp. and Pseudomonas spp. Among these samples, 13 (35.13%) were co-infected with influenza A virus. Influenza type B, co-infecting bacteria were found in five (13.51%) samples. In vitro the S. aureus protease increased the influenza HA titer after contact for 30 min at 25 ºC. Results revealed the occurrence of co-infection with proteolytic bacteria and influenza in the evaluated individuals. This finding corroborates that virus versus bacteria synergism could be able to potentiate respiratory infection, increasing damage to hosts.

Clinical and Bacteriological Survey of Diabetic Foot Infections in Lisbon

AIMS: An epidemiological survey of diabetic foot infections (DFIs) in Lisbon, stratifying the bacterial profile based on patient demographical data, diabetic foot characteristics (PEDIS classification), ulcer duration and antibiotic therapy. METHODS: A transversal observational multicenter study, with clinical data collection using a structured questionnaire and microbiological products (aspirates, biopsies or swabs collected using the Levine method) of clinically infected foot ulcers of patients with diabetes mellitus (DM). RESULTS: Forty-nine hospitalized and ambulatory patients were enrolled in this study, and 147 microbial isolates were cultured. Staphylococcus was the main genus identified, and methicillin-resistant Staphylococcus aureus (MRSA) was present in 24.5% of total cases. In the clinical samples collected from patients undergoing antibiotic therapy, 93% of the antibiotic regimens were considered inadequate based on the antibiotic susceptibility test results. The average duration of an ulcer with any isolated multi-drug resistant (MDR) organism was 29 days, and previous treatment with fluoroquinolones was statistically associated with multi-drug resistance. CONCLUSIONS: Staphylococcus aureus was the most common cause of DFIs in our area. Prevalence and precocity of MDR organisms, namely MRSA, were high and were probably related to previous indiscriminate antibiotic use. Clinicians should avoid fluoroquinolones and more frequently consider the use of empirical anti-MRSA therapy.

Delecção 1p36 – A Síndrome Não Explica Tudo…

Introdução: A criança com co-morbilidade grave é um premente desafio diagnóstico, cujo sucesso depende de uma abordagem multi-disciplinar. A síndrome de delecção 1p36, microdelecção subtelomérica de apresentação clínica pleiotrópica e multissistémica, pode incluir atraso do desenvolvimento psicomotor, alterações cardíacas, neurológicas e gastrointestinais. Caso Clínico: Filha única de pais não consanguíneos, PNV sem vacinação anti pneumocócica, com múltiplos internamentos: choque cardiogénico com miocardiopatia dilatada (3M), sépsis a S. aureus e Streptococcus do grupo G (5M) e várias intercorrencias infecciosas (varicela, gastrenterite, bronquiolite, febre sem foco). Aos 22 meses é reinternada por choque séptico com falência multi-orgânica por Streptococcus pneumoniae (serotipo 23-F), complicada de osteomielite dos ossos do antebraço e abcesso abdominal com necessidade de cirurgia. Pelos antecedentes e gravidade desta sépsis pneumocócica investigou-se eventual imunodeficiência identificando-se asplenia, confirmada por corpos de Howell-Jolly, TC abdominal e laparotomia. Retrospectivamente, para além da miocardiopatia havia má progressão ponderal com dificuldades alimentares, atraso global do desenvolvimento psicomotor, dermatose eczematosa grave e hipereosinofilia (2.410-5.680/uL), investigada por Genética, Infecciologia e Doenças Metabólicas. O cariotipo revelou monossomia da região distal ao locus 1p36 – delecção 1p36. Cintigrafia com MIBG sem evidência de neuroblastoma (risco aumentado pela síndrome). O estudo metabólico foi negativo, à excepção de défice de L-carnitina, pelo que mantem suplementos estando em curso estudo molecular de CPT2 – gene associado a défice de carnitina, na localização 1p32. Quanto à hipereosinofilia, verificou-se IgE aumentada e biopsia óssea normal pelo que iniciou prednisolona 2mg/Kg/dia com resposta favorável, estando estudo molecular específico em curso. Discussão: No fenótipo da síndrome enquadram-se o atraso global do desenvolvimento, a miocardiopatia e dificuldades alimentares. A asplenia, hipereosinofilia e dermatose eczematosa graves, não associadas a esta síndrome e de etiologia ainda a esclarecer podem-se integrar eventualmente na delecção terminal do cromossoma 1. As alterações no cariotipo carecem ainda de caracterização do ponto de quebra centromérico através de array-CGH, teste com maior especificidade para avaliar a tradução clínica dos efeitos individuais e combinados dos genes envolvidos.

Hemangiomas. Novas Terapêuticas!

Introdução: Os hemangiomas constituem a neoplasia mais frequente na criança, ocorrendo em 10-12%, na maioria dos casos com evolução favorável. A fase proliferativa, ocorre nos primeiros 4-6 meses e depois involuem em 50% dos casos, até aos 5 anos. Em hemangiomas de grandes dimensões e que interferem na função de outros órgãos, associam-se frequentemente complicações, nomeadamente a ulceração (10-15%), sobre-infecção bacteriana ou hemorragia. Descrição de Caso Clínico: Criança do sexo feminino, de 6 meses, com hemangioma de grandes dimensões, que ocupava todo o ombro, que nos dois meses prévios realizava regularmente tratamento com laser, internada por ulceração e infecção cutânea. Leucócitos 12.300/μL, neutrófilos 38,9%, plaquetas 616.000/μL e PCR 6,7 mg/dL. Foi medicada empiricamente com ceftazidima, flucloxacilina e gentamicina e ficando em curso cultura do exsudado em que posteiormente se isolou Staphylococcus aureus meticilino-sensível e Pseudomonas aeruginosa. A referir ainda anemia ferropenica grave com hemoglobina 5,2 g/dL, hematócrito 15,8% e siderémia (20 μg/dL) com necessidade de transfusão de concentrado eritrocitário e posteriormente terapêutica marcial. A ecografia abdominal revelou pequeno hemangioma hepático e a ecografia trans-fontanelar não tinha alterações. Após realização de electrocardiograma, iniciou terapêutica com propanolol na dose inicial de 0,15 mg/kg/dia com aumento gradual ate 1,5 mg/kg/dia com melhoria clínica e diminuição das dimensões e coloração do hemangioma e sem efeitos secundários a registar. Actualmente mantém terapêutica com propanolol e ferro oral, com o último valor de hemoglobina de 10,6 g/dL Conclusão: A terapêutica do hemamgioma inclui a utilização de laser, a embolização ou a excisão cirúrgica. Neste caso o tratamento convencional não resultou. O propanolol como uma nova alternativa terapêutica tem vindo a assumir uma importância crescente, na melhoria clínica destas situações. A realização de exames complementares para vigiar eventuais efeitos secundários é mandatória e a utilização de doses crescentes aumenta o perfil de segurança desta terapêutica.

Antibacterial effect (in vitro) of Moringa oleifera and Annona muricata against Gram positive and Gram negative bacteria

Antibacterial effects of aqueous and ethanolic extracts of seeds of moringa (Moringa oleifera) and pods of soursop (Annona muricata) in the concentration of 1:5 and 1:10 in volumes 50, 100, 150 and 200 µL were examined against Staphylococcus aureus, Vibrio cholerae, Escherichia coli (isolated from the organism and the aquatic environment) and Salmonella Enteritidis. Antibacterial activity (inhibition halo > 13 mm) against S. aureus, V. cholerae and E. coli isolated from the whiteleg shrimp, Litopenaeus vannmaei, was detected in aqueous and ethanolic extracts of moringa. E. coli isolated from tilapiafish, Oreochromis niloticus, was sensitive to the ethanolic extract of moringa. The aqueous extracts of soursop showed an antibacterial effect against S. aureus and V. cholerae, but the antibacterial activity by the ethanol extracts of this plant was not demonstrated.

Vigilância Epidemiológica da Infecção. Resultados de Inquéritos de Prevalência num Hospital Pediátrico

Introdução: Os Inquéritos de prevalência são estudos transversais que medem o número de doentes com infecção um determinado dia. Enquadramento: foram realizados dois inquéritos de prevalência em Portugal em anos sequenciais – 2009 e 2010. O hospital de Dona Estefânia participou em ambos. O objectivo deste estudo foi mostrar os resultados obtidos num hospital pediátrico e compará-los com resultados nacionais e do CHLC. População: Para efeitos do estudo foram excluídas grávidas e puérperas e mulheres internadas em enfermaria de ginecologia e as crianças transferidas de outros hospitais para tratarem infecções adquiridas nesses hospitais. Foram incluídos no estudo 121 doentes no primeiro ano e 126 no segundo. Resultados: A percentagem de RN foi semelhante nos dois anos (19% e 20,6%) assim como a de lactentes (24,8% e 27,8%). A taxa de infecção hospitalar foi de 11,6% em 2009 e 4,8% em 2010. A grande prematuridade (IG<28s) e o muito baixo peso (PN<1500g) como risco intrínseco e a punção venosa periférica e a cirurgia como risco extrínseco sobressaíram como os mais importantes nos dois anos. No que respeita a exposição a dispositivos invasivos, procedimentos e intervenções sobressaíram a NPT, a ventilação mecânica e os CVC. A infecção da corrente sanguínea e a pneumonia foram as localizações mais frequentes da infecção. Em 2009 houve 14,2% de infecções de órgão/espaço e 7,1% de infecção incisional/superficial em doentes operados mas em 2010 não foram registadas infecções em doentes cirúrgicos. A infecção hospitalar foi mais prevalente em unidades de cuidados intensivos, enfermaria de urologia e de queimados. Foram isolados 10 agentes infecciosos - Candida, Klebsiella, Staph aureus, E. coli e rotavirus. Os antimicrobianos mais utilizados foram cefotaxime, gentamicina, ampicilina/amoxicilina e metronidazol. Comparando com dados nacionais e do CHLC verifica-se que a percentagem de doentes com infecção hospitalar em 2010 foi superior na população pediátrica nacional excluindo o HDE e que nos dois anos foi muito superior nos adultos, sobretudo nos do Centro Hospitalar, a localização da infecção foi diferente assim como os agentes isolados e os antimicrobianos utilizados podendo concluir-se que um hospital pediátrico continua a ser uma ilha no panorama da infecção hospitalar.

EVALUATION OF ANTIMICROBIAL AND CYTOTOXIC ACTIVITIES OF PLANT EXTRACTS FROM SOUTHERN MINAS GERAIS CERRADO

The antimicrobial activity of plant hidroethanolic extracts on bacteria Gram positive, Gram negative, yeasts, Mycobacterium tuberculosis H37 and Mycobacterium bovis was evaluated by using the technique of Agar diffusion and microdilution in broth. Among the extracts evaluated by Agar diffusion, the extract of Bidens pilosa leaf presented the most expressive average of haloes of growth inhibition to the microorganisms, followed by the extract of B. pilosa flower, of Eugenia pyriformis' leaf and seed, of Plinia cauliflora leaf which statistically presented the same average of haloes inhibitory formation on bacteria Gram positive, Gram negative and yeasts. The extracts of Heliconia rostrata did not present activity. Mycobacterium tuberculosis H37 and Mycobacterium bovis(BCG) appeared resistant to all the extracts. The susceptibility profile of Candida albicans and Saccharomyces cerevisiae fungi were compared to one another and to the Gram positive Bacillus subtilis, Enterococcus faecalis and the Gram negative Salmonella typhimurium bacteria (p > 0.05). The evaluation of cytotoxicity was carried out on C6-36 larvae cells of the Aedes albopictus mosquito. The extracts of stem and flower of Heliconia rostrata, leaf and stem of Plinia cauliflora, seed of Anonna crassiflora and stem, flower and root of B. pilosa did not present toxicity in the analyzed concentrations. The highest rates of selectivity appeared in the extracts of stem of A. crassiflora and flower of B. pilosa to Staphylococcus aureus, presenting potential for future studies about a new drug development.

Septic Arthritis Presenting as Brachial Plexus Neurophaty

Bone and joint infections are rare in the neonatal period. They often present with pseudo paralysis of the affected limb due to pain and discomfort caused by movement. The existence of a concomitant neuropathy is a rare and insuffi ciently understood phenomenon with few cases described. The authors report the case of a 7-week infant, born prematurely and with Staphylococcus aureus neonatal sepsis, who presented to the emergency room with a paretic right upper limb. Osteoarticular infection complicated with brachial plexus neuropathy was considered and MRI and electromyography the confi rmed diagnosis. There was a good outcome after antibiotic treatment and functional rehabilitation.

EVALUATION OF METHODS IN DETECTING VANCOMYCIN MIC AMONG MRSA ISOLATES AND THE CHANGES IN ACCURACY RELATED TO DIFFERENT MIC VALUES

INTRODUCTION: Methicillin-Resistant Staphylococcus aureus (MRSA) presenting reduced susceptibility to vancomycin has been associated to therapeutic failure. Some methods used by clinical laboratories may not be sufficiently accurate to detect this phenotype, compromising results and the outcome of the patient. OBJECTIVES: To evaluate the performance of methods in the detection of vancomycin MIC values among clinical isolates of MRSA. MATERIAL AND METHODS: The Vancomycin Minimal Inhibitory Concentration was determined for 75 MRSA isolates from inpatients of Mãe de Deus Hospital, Porto Alegre, Brazil. The broth microdilution (BM) was used as the gold-standard technique, as well as the following methods: E-test® strips (BioMérieux), M.I.C.E® strips (Oxoid), PROBAC® commercial panel and the automated system MicroScan® (Siemens). Besides, the agar screening test was carried out with 3 µg/mL of vancomycin. RESULTS: All isolates presented MIC ≤ 2 µg/mL for BM. E-test® had higher concordance (40%) in terms of global agreement with the gold standard, and there was not statistical difference among E-test® and broth microdilution results. PROBAC® panels presented MICs, in general, lower than the gold-standard panels (58.66% major errors), while M.I.C.E.® MICs were higher (67.99% minor errors). CONCLUSIONS: For the population of MRSA in question, E-test® presented the best performance, although with a heterogeneous accuracy, depending on MIC values.

Abcessos Renais - Revisão

Baseados num caso de associação de abcessos renal, perirrenal e de quisto renal infectado, ocorrendo após biopsia prostática, os autores fazem revisão bibliográfica dos abcessos renais, classificados segundo características anatómicas perinéfrico, cortical e cortico- -medular (nefrite bacteriana aguda focal/multifocal, pielonefrite enfisematosa e pielonefrite xantogranulomatosa). Os abcessos renais são mais frequentes em diabéticos, menos vezes em alcoólicos, desnutridos e imunodeprimidos, estando associados geralmente a pielonefrites recorrentes, refluxo vesicoureteral, litíase urinária, ou resultam de êmbolos sépticos hematogéneos originados em focos extra-renais de infecção. A Escherichia coli é responsável pela maioria dos casos, e menos vezes a Klebsiella Proteus, Enterobacter, Pseudomonas, e Estafilococo aureus. Descrevem-se a expressão clínica, complicações evolutivas e diagnóstico radiológico, enfatizando-se as infecções acompanhadas de formação de gás. Referem-se opções terapêuticas médico-cirúrgicas, cujas indicações dependem do diagnóstico precoce, complicações e factores predisponentes.

Pesquisa de novos metabolitos secundários bioactivos em bactérias de sedimentos marinhos

Dissertação para obtenção do Grau de Mestre em Genética Molecular e Biomedicina