Effect of cationic surfactant on the physicochemical and antibacterial properties of colloidal systems (emulsions and microemulsions).

Colloidal systems have been used to encapsulate, protect and release essential oils in mouthwashes. In this study, we investigated the effect of cetylpyridinium chloride (CPC) on the physicochemical properties and antimicrobial activity of oil-in-water colloidal systems containing tea tree oil (TTO) and the nonionic surfactant polysorbate 80. Our main aim was to evaluate whether CPC could improve the antimicrobial activity of TTO, since this activity is impaired when this essential oil is encapsulated with polysorbate 80. These systems were prepared with different amounts of TTO (0-0.5% w/w) and CPC (0-0.5% w/w), at a final concentration of 2% (w/w) polysorbate 80. Dynamic light scattering (DLS) results revealed the formation of oil-swollen micelles and oil droplets as a function of TTO concentration. Increases in CPC concentrations led to a reduction of around 88% in the mean diameter of oil-swollen micelles. Although this variation was of only 20% for the oil droplets, the samples appearance changed from turbid to transparent. The surface charge of colloidal structures was also markedly affected by the CPC as demonstrated by the transition in zeta potential from slightly negative to highly positive values. Electron paramagnetic resonance (EPR) studies showed that this transition is followed by significant increases in the fluidity of surfactant monolayer of both colloidal structures. The antimicrobial activity of colloidal systems was tested against a Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureaus) bacteria. Our results revealed that the inhibition of bacterial growth is observed for the same CPC concentration (0.05% w/w for E. coli and 0.3% w/w for S. aureus) regardless of TTO content. These findings suggest that TTO may not act as an active ingredient in polysorbate 80 containing mouthwashes.

Ozonated oil effect for prevention of medication-related osteonecrosis of the jaw (MRONJ) in rats undergoing zoledronic acid therapy.

OBJECTIVES: The aim of this study was to evaluate the preventive effect of ozonated oil on the development of MRONJ-like lesions at tooth extraction sites in rats submitted to zoledronic acid treatment. MATERIALS AND METHODS: Twelve rats were divided into two groups. Each rat received an injection of zoledronic acid solution once a week for 5 weeks before having its upper first molar extracted. In group 1, the clotted socket was maintained, while in the group 2, the socket was treated with ozonated oil for 10 min/day during 3 days. After euthanasia, block resection was performed for histological analysis. Necrotic bone was defined as the area of the bone with empty osteocyte lacunae and vital bone as the area with osteocyte-occupied lacunae. RESULTS: There was no statistically significant difference between the groups in the average area of vital bone (p = 0.2248) and the average area of necrotic bone (p = 0.1208). However, the average area of vital bone in group 1 was smaller (24.1 ± 2.9 cells/cm2) than in group 2 (26.8 ± 4.2 cells/cm2), and the average area of necrotic bone in group 1 was higher (7.0 ± 2.5 cells/cm2) than in group 2 (4.0 ± 1.1 cells/cm2), indicating that ozonated oil may reduce the development of osteonecrosis. CONCLUSIONS: Our findings suggest that ozonated oil might prevent MRONJ-like lesions at tooth extraction sites in rats submitted to a disease induction protocol. Further research should be conducted to confirm this hypothesis. CLINICAL RELEVANCE: MRONJ has been reported as a complication of surgical dental procedures, and there are currently no predictable preventive therapies.

Subtyping Brazilian Yersinia pestis strains by pulsed-field gel electrophoresis.

We subtyped Brazilian Yersinia pestis strains by pulsed-field gel electrophoresis (PFGE). This was done with 22 Brazilian Y. pestis strains: 17 from an outbreak and 5 from endemic routine surveillance. The strains were divided into 2 groups (I and II), 8 subgroups (A-H) and 19 PFGE profiles or pulsotypes. PFGE did not separate outbreak from non-outbreak strains, as identical pulsotype patterns were found among outbreak strains and strains obtained from surveillance. However, it was able to detect intraspecific genetic diversity among Brazilian strains. This PFGE technique was able to differentiate a homogeneous group of Brazilian Y. pestis strains.

Avaliação clínica de bochechos com extratos de Aroeira (Schinus terebinthifolius) e Camomila (Matricaria recutita L. ) sobre a placa bacteriana e a gengivite / Clinical evaluation of mouthwash with extracts from aroeira (Schinus terebinthifolius) and chamomile (Matricaria recutita L. ) on plaque and gingivitis

A presente pesquisa objetivou avaliar clinicamente o efeito de bochechos à base de extratos das plantas medicinais, aroeira (Schinus terebinthifolius) e camomila (Matricaria recutita L.), sobre o controle da placa bacteriana e o tratamento da gengivite. Para tanto, foi realizado um ensaio clínico randomizado, duplo cego, intervencionista, envolvendo 59 indivíduos adultos atendidos na Clínica do Curso de Odontologia da Universidade Estadual da Paraíba (UEPB). A amostra foi constituída por pacientes portadores de gengivite crônica. A referida amostra foi selecionada aleatoriamente e dividida em três grupos: bochecho com Clorexidina (grupo controle positivo); bochecho com Camomila (grupo teste 1); bochecho com Aroeira (grupo teste 2). Durante a primeira visita do paciente, e, previamente à realização dos bochechos, todos foram orientados quanto à higiene bucal e submetidos ao procedimento de raspagem e alisamento radicular (RAR) da boca toda em uma única sessão. Os bochechos foram realizados a partir do primeiro atendimento clínico até o 15º dia após o início do tratamento, na frequência de duas vezes ao dia. Para avaliação da condição periodontal da amostra realizada no 1º, 7º e 15º dias foram aplicados os Índices de Sangramento Gengival (ISG) e de Placa (IP). Os pacientes foram reavaliados 7 e 15 dias após o início do uso do respectivo bochecho. Os resultados apontaram que o IP e o ISG apresentaram redução significativa nos três grupos. Quanto ao IP, o bochecho de camomila obteve a maior redução de acúmulo de placa e o bochecho de aroeira, a menor redução. Para os índices de sangramento, os resultados foram equivalentes, de forma que não foram consideradas diferenças estatisticamente significativas entre os bochechos. Foram considerados satisfatórios os bochechos a base de Camomila (Matricaria recutita L.) e Aroeira (Schinus terebinthifolius) na redução do quadro de inflamação gengival da amostra, sendo o bochecho de Camomila (Matricaria recutita L.) o que apresentou melhor desempenho na redução do índice de placa bacteriana.

This study aimed to clinically evaluate the effect of mouthwash with extracts from the medicinal plants aroeira (Schinus terebinthifolius) and chamomile (Matricaria recutita L.) on plaque control and gingivitis treatment. Thus, a randomized, double-blind interventional clinical trial was conducted, involving 59 adults treated at the Clinics of the Dentistry Program of Univ Estadual da Paraíba (UEPB). The sample consisted of patients with chronic gingivitis. This sample was randomly selected and divided into three groups: mouthwash with chlorhexidine (positive control group), mouthwash with chamomile (test group 1); mouthwash with aroeira (test group 2). During the first visit, and prior to rinses, all patients were instructed in oral hygiene and subjected to scaling and root planing procedure (SRP) of the whole mouth in one single session. Rinses occurred from the first clinical appointment to the 15th day after the beginning of treatment, twice a day. To evaluate the periodontal condition of the sample on the 1st, 7th and 15th days, Gingival Bleeding Index (GBI) and Plaque Index (PI) were used. The patients were reassessed at 7 and 15 days after the beginning of the respective rinses. Results indicated that PI and GBI significantly decreased in all three groups. As to PI, chamomile mouthwash led to the greatest reduction in plaque buildup, while aroeira mouthwash resulted in the smallest reduction. For bleeding rates, results were equivalent so that statistical differences among rinses were not considered significant. Mouthwashes with chamomile (Matricaria recutita L.) and aroeira (Schinus terebinthifolius) were considered satisfactory in reducing gingival inflammation in the sample; in addition, mouthwash with chamomile (Matricaria recutita L.) showed the best performance in reducing the plaque index.

Oral health profile of cirrhotic patients awaiting liver transplantation in the Brazilian Northeast.

BACKGROUND: Infections are a frequent cause of morbidity and mortality among postoperative liver transplant (OLT) patients and a leading cause of decompensated chronic liver disease (CLD) among patients awaiting the procedure. Oral lesions that are frequently observed in subjects with CLD may represent foci for systemic infections before and after OLT. AIMS: To evaluate the oral health profile of patients with CLD awaiting OLT. METHODS: One hundred thirty one patients including 100 males of overall mean age 49.5 ± 10.8 years with CLD were listed for OLT and examined for oral health status according to a established protocol. RESULTS: One hundred thirty (99%) patients were partially edentulous; 66 (51%) had chewing difficulties; and 63 (48%) experienced reduced salivary flow. With respect to periodontal disease and oral infections, 68 (25%) had periodontitis, 63 (48%) had periapical lesion, 64 (49%) had abscesses, and 59 (45%) had root fragments. Loss of follow-up was observed in 21 subjects. Among the 110 other patients, 63 (57%) underwent dental treatments with complications in only two cases. Interestingly, mortality was significantly lower among treated (31%) versus nontreated patient (79%; P<.001). CONCLUSIONS: Poor oral health status observed in most CLD patients may represent a source of systemic infections before and after OLT. Treatment of such lesions was feasible in the majority of the patients and seemed to be associated with a reduction in mortality.

Genetic divergence between two sympatric species of the Lutzomyia longipalpis complex in the paralytic gene, a locus associated with insecticide resistance and lovesong production.

The sandfly Lutzomyia longipalpis s.l. is the main vector of American Visceral Leishmaniasis. L. longipalpis s.l. is a species complex but until recently the existence of cryptic sibling species among Brazilian populations was a controversial issue. A fragment of paralytic (para), a voltage dependent sodium channel gene associated with insecticide resistance and courtship song production in Drosophila, was isolated and used as a molecular marker to study the divergence between two sympatric siblings of the L. longipalpis complex from Sobral, Brazil. The results revealed para as the first single locus DNA marker presenting fixed differences between the two species in this locality. In addition, two low frequency amino-acid changes in an otherwise very conserved region of the channel were observed, raising the possibility that it might be associated with incipient resistance in this vector. To the best of our knowledge, the present study represents the first population genetics analysis of insecticide resistance genes in this important leishmaniasis vector.

Comparative analysis of a chemotherapy effect on the cuticular surface of Wuchereria bancrofti adult worms in vivo.

Wuchereria bancrofti is the main species responsible for human lymphatic filariasis and remains a major public health problem in tropical countries around the world. Diethylcarbamazine (DEC) has been used for decades in control programs as an effective microfilaricide, although its efficacy in killing adult worms is only around 50% and its direct mode of action is unclear. Recently, in an attempt to control and eliminate lymphatic filariasis, WHO has recommended albendazole (ALB), a broad-spectrum anthelminthic combined with DEC or ivermectin for mass treatment. Some studies have shown that DEC alone blocks oogenesis, fertilization in adult worms, and loss of the microfilarial sheath of several filarial species, whereas ALB is thought to target nematode tubulin. So far, the direct effect of ALB in combination with DEC has not been described in W. bancrofti adult worms. Therefore, the purpose of this study is to investigate by scanning electron microscopy if DEC coadministered with ALB can induce in vivo morphological alterations of the W. bancrofti adult worm surface obtained from a patient in whom the adult worm remained alive, checked serially by ultrasonography for 2 months after antifilarial treatment. Our analysis demonstrates that worms presented morphologic alterations in some regions suggesting cuticular surface damage. On the other hand, adult worms that were recovered from a patient treated with DEC alone after a single dose did not show such any abnormalities.

Children and adolescents infected with Wuchereria bancrofti in Greater Recife, Brazil: a randomized, year-long clinical trial of single treatments with diethylcarbamazine or diethylcarbamazine-albendazole.

In filariasis-endemic areas beyond sub-Saharan Africa, the World Health Organization's recommended strategy for interrupting transmission of the causative parasites is annual, single-dose, mass treatment with a combination of diethylcarbamazine (DEC; given at 6 mg/kg) and albendazole (ALB; given at 400 mg) for 4-6 years (the minimum estimated life-span of the adult parasites). In an open, hospital-based, randomized and controlled trial, with a blinded evaluation of outcome, 82 children and adolescents from Recife, all with Wuchereria bancrofti microfilaraemias, were given either DEC alone (6 mg/kg) or the same dose of DEC combined with ALB (at 400 mg/patient). Every 90 days for 1 year after the single treatment, each patient was checked for microfilaraemia by the filtration of up to 5 ml of venous blood collected at night. One year post-treatment, 16 (39%) of the 41 patients given DEC alone and 20 (49%) of the 41 given DEC-ALB were found microfilaraemic (relative risk=0.8, with a 95% confidence interval of 0.49-1.31) and the corresponding geometric mean levels of microfilaraemia were 2.0% and 1.8% of the levels recorded immediately pre-treatment, respectively (P>0.05). In terms of the prevalences and intensities of microfilaraemia, therefore, the addition of ALB to the DEC appeared to offer no significant benefit.

Molecular evolution of the cacophony IVS6 region in sandflies.

A number of insects produce acoustic signals during courtship. Genes involved in the control of the courtship song are particularly interesting from an evolutionary viewpoint because interspecific variation in this signal is potentially important as a reproductive isolation mechanism and, as a consequence, in the speciation process. The cacophony gene was identified by a mutation affecting the "lovesong" in Drosophila melanogaster. Phlebotomine sandflies (Diptera: Psychodidae) also produce acoustic stimuli during courtship and therefore cacophony can be used as an interesting molecular marker in evolutionary studies in these important disease vectors. In this paper we have studied the molecular evolution of the IVS6 region of cacophony in sandflies. We compared the level of divergence in the exon sequences encoding this conserved domain in Drosophila and Phlebotomines. We also analysed the high level of variation in an intron that is present in sandflies but that was lost in Drosophila during evolution. The available cacophony sequences were also used for a phylogenetic analysis of some species of the Neotropical genus Lutzomyia.

New molecular markers for phlebotomine sand flies.

Using degenerate-primers PCR we isolated and sequenced fragments from the sand fly Lutzomyia longipalpis homologous to two behavioural genes in Drosophila, cacophony and period. In addition we identified a number of other gene fragments that show homology to genes previously cloned in Drosophila. A codon usage table for L. longipalpis based on these and other genes was calculated. These new molecular markers will be useful in population genetics and evolutionary studies in phlebotomine sand flies and in establishing a preliminary genetic map in these important leishmaniasis vectors.

Solvent accessibility to aspartyl and succinimidyl residues at positions 7 and 23 in the amyloid beta 1-28 peptide.

The water accessibilities to aspartyl residues at positions 7 and 23 in the amyloid beta 1-28 peptide associated with Alzheimer's Disease have been calculated using different techniques. These accessibilities of water were compared to those of the succinimidyl residues (SUC) replacing the aspartyl ones (ASP). It has been possible to ascertain that these modifications (ASP--->SUC) lead to a significant increase in the water accessibility to the backbone and alpha-carbon atom of the SUC7 and SUC23 residues. It is suggested that the spontaneous transformation of the ASP--->SUC might lead to an increase of the racemization rates due to the higher accessibility of water at these sites. It is also proposed that the behavior of the adjacent residues in the selectivity of the racemization is to control the water accessibility at the reactive residue.

Intraaortic balloon pump support during coronary angioplasty. Initial experience.

OBJECTIVE: To evaluate the use of the intraaortic balloon (IAoB) in association with coronary angioplasty in high-risk patients. METHODS: Fourteen high-risk patients unresponsive to clinical therapy and with formal contraindication to surgical revascularization were treated by coronary angioplasty, most of which was followed by stenting. All procedures were performed with circulatory support with the IAoB. This study reports the early results and the late findings after 12 months of follow-up. Six patients had multivessel coronary disease; of these, four had left main equivalent lesions and two had unprotected left main coronary artery disease, one of whom had severe "end-vessel" stenosis and the other was a patient with Chagas' disease with single-vessel lesion. Eleven patients had a left ventricular ejection fraction < 30%. RESULTS: In 100% of the patients, the procedures were initially successful. Two patients had severe bleeding during the withdrawal of the left femoral sheath. At the end of twelve months, 4 patients were asymptomatic and the others were clinically controlled. There were two late deaths in the 7th and 11th months. CONCLUSION: The combined use of the intraaortic balloon pump and percutaneous coronary angioplasty in high-risk patients with acute ischemic syndromes provides the necessary hemodynamic stability to successfully perform the procedures.

Plural origins of molecular homochirality in our biota Part II. The relative stabilities of homochiral and mixed oligoribotides and peptides.

By computer simulations--molecular mechanics and molecular dynamics with the amber force field (Weiner et al, (1986), J. Comp. Chem. 7, 230-252)--we have determined the stabilities of oligoribotide strands built with D- and L-riboses, and of peptide chains with D- and L-amino acid residues. In particular, complementary double-chains of oligoribotides were studied, since they are an important feature of the growing mechanism of modern nucleic acids. Peptide chains on the other hand, grow without need of a template. We found that mixed oligoribotides are less stable than homochiral ones, and that this chiral effect is less noticeable in peptide chains. The results support the interpretation that L-riboses act as terminators to the template-assisted growth of oligo-r-GD (enantiometric cross-inhibition; Joyce et al., (1987), Proc. Natl. Acad. Sci. USA 84, 4398-4402). Based on this effect, a chemical pathway is proposed which could, under assumed prebiotic conditions, bypass the hindrance of homochiral growth.

Surgical treatment of active valvular infective endocarditis.

A review is presented of 20 patients consecutively operated on for acute valvular endocarditis. The diagnosis was established from at least two of the criteria: (a) typical clinical features, (b) two blood cultures positive for the same causal microorganism, and (c) echocardiographic evidence of vegetations. In all cases there was histologic evidence of active infection in the surgical specimen. Only three of the 20 patients had no previous cardiac disease. The most common causal agent was Staphylococcus aureus. The indications for surgery were refractory cardiac failure or infection (18 and 2 cases, respectively). Aortic valve replacement was performed in 16 of the 20 cases, suggesting that aortic valvulopathy aggravates the course of infective endocarditis and increases the risk of heart failure. The overall mortality rate was 30%. All surviving patients were infection-free at postoperative bacteriologic follow-up. Surgery is considered to be the management of choice in active valvular, therapy-resistant bacterial endocarditis with or without cardiac failure.

Estudo ecocardiografico na esclerose sistemica progressiva. / Echocardiographic study in progressive systemic sclerosis

Os autores estudam, por ecocardiografia, 18 portadores de esclerose sistemica progressiva, correlacionando os achados com dados clinicos. Mostram a importancia deste metodo nao invasivo para detectar alteracoes pericardicas, miocardicas e endocardicas, mesmo em pacientes sem quaisquer manifestacoes aparentes para o lado do aparelho cardiovascular. O envolvimento pericardico foi detectado em 39%. Alteracoes de valva mitral e aortica ocorreram 39% dos casos. Comprometimento miocardico ocorreu em 11 casos e pancardite em 2 casos. Consideram o ecocardiograma um importante metodo para detectar a cardiopatia esclerodermica e para seguir o curso da doenca