The genetic landscape of mitochondrial diseases in the next-generation sequencing era: a Portuguese cohort study

Introduction: Rare disorders that are genetically and clinically heterogeneous, such as mitochondrial diseases (MDs), have a challenging diagnosis. Nuclear genes codify most proteins involved in mitochondrial biogenesis, despite all mitochondria having their own DNA. The development of next-generation sequencing (NGS) technologies has revolutionized the understanding of many genes involved in the pathogenesis of MDs. In this new genetic era, using the NGS approach, we aimed to identify the genetic etiology for a suspected MD in a cohort of 450 Portuguese patients. Methods: We examined 450 patients using a combined NGS strategy, starting with the analysis of a targeted mitochondrial panel of 213 nuclear genes, and then proceeding to analyze the whole mitochondrial DNA. Results and Discussion: In this study, we identified disease-related variants in 134 (30%) analyzed patients, 88 with nuclear DNA (nDNA) and 46 with mitochondrial DNA (mtDNA) variants, most of them being pediatric patients (66%), of which 77% were identified in nDNA and 23% in mtDNA. The molecular analysis of this cohort revealed 72 already described pathogenic and 20 novel, probably pathogenic, variants, as well as 62 variants of unknown significance. For this cohort of patients with suspected MDs, the use of a customized gene panel provided a molecular diagnosis in a timely and cost-effective manner. Patients who cannot be diagnosed after this initial approach will be further selected for whole-exome sequencing. Conclusion: As a national laboratory for the study and research of MDs, we demonstrated the power of NGS to achieve a molecular etiology, expanding the mutational spectrum and proposing accurate genetic counseling in this group of heterogeneous diseases without therapeutic options.

Polymorphisms and haplotypes of TOLLIP and MUC5B are associated with susceptibility and survival in patients with fibrotic hypersensitivity pneumonitis

INTRODUCTION AND OBJECTIVES

Hypersensitivity pneumonitis (HP) is an interstitial lung disease with diverse clinical features that can present a fibrotic phenotype similar to idiopathic pulmonary fibrosis (IPF) in genetically predisposed individuals. While several single nucleotide polymorphisms (SNPs) have been associated with IPF, the genetic factors contributing to fibrotic HP (fHP) remain poorly understood. This study investigated the association of MUC5B and TOLLIP variants with susceptibility, clinical presentation and survival in Portuguese patients with fHP.

MATERIAL AND METHODS

A case-control study was undertaken with 97 fHP patients and 112 controls. Six SNPs residing in the MUC5B and TOLLIP genes and their haplotypes were analyzed. Associations with risk, survival, and clinical, radiographic, and pathological features of fHP were probed through comparisons among patients and controls.

RESULTS

MUC5B rs35705950 and three neighboring TOLLIP variants (rs3750920, rs111521887, and rs5743894) were associated with increased susceptibility to fHP. Minor allele frequencies were greater among fHP patients than in controls (40.7% vs 12.1%, P<0.0001; 52.6% vs 40.2%, P = 0.011; 22.7% vs 13.4%, P = 0.013; and 23.2% vs 12.9%, P = 0.006, respectively). Haplotypes formed by these variants were also linked to fHP susceptibility. Moreover, carriers of a specific haplotype (G-T-G-C) had a significant decrease in survival (adjusted hazard ratio 6.92, 95% CI 1.73-27.64, P = 0.006). Additional associations were found between TOLLIP rs111521887 and rs5743894 variants and decreased lung function at baseline, and the MUC5B SNP and radiographic features, further highlighting the influence of genetic factors in fHP.

CONCLUSION

These findings suggest that TOLLIP and MUC5B variants and haplotypes may serve as valuable tools for risk assessment and prognosis in fibrotic hypersensitivity pneumonitis, potentially contributing to its patient stratification, and offer insights into the genetic factors influencing the clinical course of the condition.

Elastic Softness of Hybrid Lead Halide Perovskites

Much recent attention has been devoted towards unraveling the microscopic optoelectronic properties of hybrid organic-inorganic perovskites. Here we investigate by coherent inelastic neutron scattering spectroscopy and Brillouin light scattering, low frequency acoustic phonons in four different hybrid perovskite single crystals: MAPbBr_{3}, FAPbBr_{3}, MAPbI_{3}, and α-FAPbI_{3} (MA: methylammonium, FA: formamidinium). We report a complete set of elastic constants characterized by a very soft shear modulus C_{44}. Further, a tendency towards an incipient ferroelastic transition is observed in FAPbBr_{3}. We observe a systematic lower sound group velocity in the technologically important iodide-based compounds compared to the bromide-based ones. The findings suggest that low thermal conductivity and hot phonon bottleneck phenomena are expected to be enhanced by low elastic stiffness, particularly in the case of the ultrasoft α-FAPbI_{3}.

Lipocalin-2 regulates adult neurogenesis and contextual discriminative behaviours

In the adult mammalian brain, newborn granule cells are continuously integrated into hippocampal circuits, and the fine-tuning of this process is important for hippocampal function. Thus, the identification of factors that control adult neural stem cells (NSCs) maintenance, differentiation and integration is essential. Here we show that the deletion of the iron trafficking protein lipocalin-2 (LCN2) induces deficits in NSCs proliferation and commitment, with impact on the hippocampal-dependent contextual fear discriminative task. Mice deficient in LCN2 present an increase in the NSCs population, as a consequence of a G0/G1 cell cycle arrest induced by increased endogenous oxidative stress. Of notice, supplementation with the iron-chelating agent deferoxamine rescues NSCs oxidative stress, promotes cell cycle progression and improves contextual fear conditioning. LCN2 is, therefore, a novel key modulator of neurogenesis that, through iron, controls NSCs cell cycle progression and death, self-renewal, proliferation and differentiation and, ultimately, hippocampal function.

Uso de Dendrímeros de Poliamidoamina como Método de Biomineralização de Estrutura Dentária

O presente estudo tem como objetivo revisar a literatura e expor as diferentes aplicações odontológicas dos dendrímeros de poliamidoamina (PAMAM). Para tanto foram utilizadas as bases de dados PubMed, SciELO e Science Direct, abrangendo-se artigos desde 2013 até 2017, através dos descritores (inglês/português). Com base nos critérios de exclusão foram retirados do trabalho, pesquisas com metodologias não definidas ou com deficiência de informações, além de estudos não diretamente relacionados com o objetivo do projeto. Ficaram incluídas no estudo, pesquisas in vitro, assuntos relacionados à prática da odontologia restauradora e artigos que apresentaram resultados significativos. Ao todo foram obtidos 9 artigos dos quais 4 seguiram selecionados após análise de título e Resumo. Observou-se que os dendrímeros de Poliamidoamina de geração 4.0 (4G) podem ser absorvidos na superfície de esmalte desmineralizado e induzir a formação de cristais de hidroxiapatita, de mesma estrutura e orientação, para a remineralização do mesmo. Além disso, outros estudos apresentaram valores potenciais no uso de dendrímeros PAMAM 4G na biomineralização de túbulos dentinários desmineralizados. Concluímos que estudos laboratoriais do uso de Dendrímeros PAMAM já vêm sendo desenvolvidos para testar seus efeitos positivos ou negativos na aplicação odontológica, no entanto, embora conceitualmente promissora, necessita ser extensivamente avaliada em análises laboratoriais e clínicas antes que seja incluída na rotina odontológica.Palavras-chave: Dendrimers. Dentistry. Biopolymers.

Clareamento Dentário com Dentifrício Contendo Covarina Azul

O presente trabalho tem como objetivo avaliar a efetividade do clareamento dentário imediato com dentifrício contendo covarina azul. Realizou-se uma revisão de literatura na base de dados PubMed, utilizando os descritores “tooth bleaching”, “bleaching agents” e “dentifrices”, no período de 2007 a 2017. Foram encontrados na busca 115  artigos científicos, que com a avaliação dos títulos    e resumos resultou na exclusão de 110, restando 5 artigos. Os critérios de inclusão foram revisões de literatura, estudos in vitro e  in vivo que avaliassem o efeito imediato clareador de dentifrícios contendo covarina azul. Foram excluídos estudos clínicos que avaliassem a sensibilidade dentária após o uso do dentifrício. Dentifrícios contendo covarina azul para clareamento dentário tem como propriedade a deposição de uma fina camada de covarina sobre a superfície do dente, que causa um efeito óptico perceptível imediatamente após o tratamento e pode persistir por um período de 8 horas. Para análise da coloração dentária foi usado o sistema CIELab, que mostrou o efeito clareador do dentifrício com covarina azul em comparação ao controle. Em relação à abrasividade do esmalte, estudos in vitro e in vivo demonstraram que o dentifrício não apresentou um efeito abrasivo indevido ao substrato dentário. Conclui-se que o dentifrício com covarina azul demonstra-se como uma nova alternativa para clareamento dentário imediato, porém novos estudos são necessários para avaliar o seu efeito ao longo do tempo.Palavras-chave: Tooth Bleaching. Bleaching Agents. Dentifrices.

Uso da Quitosana em Odontologia Restauradora: uma Revisão de Literatura

O objetivo do presente trabalho foi buscar os diferentes usos da quitosana na odontologia assim como avaliar suas vantagens e desvantagens. Revisou-se a literatura nos bancos de dados PubMed e Science Direct, entre 2007 e 2017, por meio das palavras- chaves (inglês/português): chitosan, dentin e dentistry, procurados em combinação, sendo encontrados 46 artigos, dos quais 10 foram selecionados segundo avaliação de título e Resumo. Como critérios de inclusão foram utilizados artigos que apresentavam aplicações práticas da quitosana na odontologia restauradora, e os critérios de exclusão foram os artigos que não tinham uma metodologia bem definida. A quitosana tem sido utilizada para combater as bactérias na dentina, atuando de diferentes formas em bactérias gram-positivas e gram-negativas, podendo até provocar a regeneração do tecido da dentina. Outra característica desse material é sua ação coagulante, diminuindo o período de coagulação do sangue. Este biomaterial pode alterar o colágeno e apresentar melhoras na sua propriedade, como a resistência de união, aumento das propriedades e estabilidade mecânicas. Porém, quando colocado em maior quantidade, este, apresenta desvantagens, como a obliteração de espaços interfibrilares que causam efeitos adversos na ligação a dentina. Entretanto, ainda existem poucos estudos clínicos que comprovem bons resultados envolvendo a aplicação desta solução.Palavras-chave: Chitosan. Dentin e Dentistry.

Estudo Comparativo da Estabilidade Dimensional em Diferentes tipos de Materiais de Moldagem

O objetivo foi analisar a estabilidade dimensional de diferentes tipos de materiais de moldagem. Um estudo quantitativo, experimental “in vitro” foi realizado. Foram confeccionados 300 corpos de prova a partir de uma matriz padronizada (n15) nos quais foram avaliados o peso com o auxílio de uma balança de precisão e o volume com um paquímetro digital imediatamente, 10 min, 24 horas, 3 dias e 5 dias após a presa do material em diferentes armazenagens (seca ou úmida). Os corpos de prova foram feitos utilizando três tipos de alginatos, Jeltrate Dustless – Dentsply (J), Cavex ColorChange – Cavex (C) e Hydrogum 5 – Zhermack (H5), além do silicone por adição Scan Putty-Yller (SA). Os dados foram analisados utilizando ANOVA e teste de Tukey (p<0,05).O peso dos três alginatos foram diminuídos estatisticamente (p<0,01) após 3 e 5 dias de armazenagem úmida. O H5 também demonstrou alteração com a armazenagem seca por 3 e 5 dias. O volume foi reduzido estatisticamente (p<0,05) com os três alginatos após 3 e 5 dias, entretanto, após 1 dia já houve alteração significativa em J e H5. O Scan em ambiente seco (p0,978) ou úmido (p0,072) não mostrou diferença no volume nem peso mesmo após 5 dias. Portanto, com os alginatos Hydrogum 5 e Jeltrate Dustless não se deve esperar mais de 24 horas para vazar o gesso, mesmo em ambiente úmido. A Cavex independentemente do tipo de armazenagem, pode ser vazado respectivamente, em 24 horas, mas não após 3 e 5 dias. O silicone Scan é estável dentro de 5 dias.Palavras-chave: Dental Materials. Alginates. Silicone.

Associação do Ethanol-Wet Bonding com Técnicas de Biomodificação Dentinária: uma Revisão de Literatura

O presente estudo objetivou realizar uma revisão da literatura sobre a técnica ethanol-wet bonding (EWB), mostrando se esta técnica pode aumentar a durabilidade de interfaces adesivas e o efeito do seu uso em conjunto com técnicas de biomodificação dentinária. Foi realizada uma busca nas bases de dados eletrônicas Pubmed e Bireme e incluídos trabalhos nas línguas inglesa e portuguesa publicados no período de 2007 à 2017, através dos termos: “Ethanol”, “Dental Adhesive” e “Collagen”. Foram excluídos artigos com metodologia duvidosa, duplicados e aqueles não compatíveis com os objetivos deste trabalho. Foram encontrados 63 trabalhos, que após análise, 18 destes trabalhos se adequaram aos critérios de inclusão e exclusão. A partir da revisão de literatura é possível considerar que a técnica EWB permite uma melhor infiltração dos monômeros hidrofóbicos na matriz de colágeno, e assim, diminui a sorção de água e a clivagem hidrolítica por enzimas catalizadoras de colágeno e previne a separação de fase de monômeros resinosos hidrofóbicos, como o BisGMA. Um estudo verificou que a camada híbrida criada pela técnica EWB continham fibrilas de colágeno com diâmetro fibrilar reduzido e espaços interfibrilares aumentados, características nunca observadas em camadas híbridas criadas durante a water-wet bonding. Três estudos verificaram que o efeito inibidor de MMPs da clorexidina pode ser comprometido quando a água é removida incompletamente durante a adesão dentinária. São necessários estudos clínicos de longo prazo para avaliar a durabilidade dessas restaurações.Palavras-chave: Collagen. Dental Adhesive. Ethanol.

Effect of replacing ground corn and soybean meal with licuri cake on the performance, digestibility, nitrogen metabolism and ingestive behavior in lactating dairy cows

Licuri (Syagrus coronate) cake is a biodiesel by-product used in ruminant feed as a beneficial energy source for supplementation in managed pastures. The objective was to evaluate the performance, digestibility, nitrogen balance, blood metabolites, ingestive behavior and diet profitability of eight crossbred Holstein (3/4)×Gyr (5/8) multiparous cows (480±25 kg BW and 100 days milking) grazing and supplemented with licuri cake partially replacing ground corn and soybean meal in concentrate (0, 200, 400 and 600 g/kg in dry matter (DM)), distributed in an experimental duplicated 4×4 Latin square design. Licuri cake partially replacing ground corn and soybean meal increased (P<0.01) the intake and digestibility of ether extract and decreased the non-fiber carbohydrates; however, there were no influences on the intakes of DM, CP, NDF and total digestible nutrients (TDN). The digestibilities of DM, CP and NDF were not influenced by licuri cake addition. There was a decrease trend on TDN digestibility (P=0.08). Licuri cake replacing ground corn and soybean meal in concentrate did not affect the intake; fecal, urinary and mammary excretions; N balance; and triglycerides concentrations. However, the blood urea nitrogen (P=0.04) concentration decreased with the licuri cakes inclusion in cow supplementation. There was an increasing trend for serum creatinine (P=0.07). Licuri cake inclusion did not affect body condition score, production, yield, protein, lactose, total solids and solid non-fat contents of milk and Minas frescal cheese. There was a linear decrease in average daily weight gain (g/day). The milk fat concentration and cheese fat production (P<0.1) presented a linear increase with partial replacement of ground corn and soybean meal with licuri cakes. The addition of licuri cake did not alter the time spent feeding, ruminating or idling. There was an increasing trend in NDF feeding efficiency (P=0.09). The replacing of ground corn and soybean meal with licuri cake up to 600 g/kg decreased the concentrate cost by US$0.45/cow per day. Licuri cake replacing corn and soybeans (400 g/kg) in concentrate promoted a profit of US$0.07/animal per day. Licuri cake is indicated to concentrate the supplementation of dairy cows with average productions of 10 kg/day at levels up to 400 g/kg in the concentrate supplement because it provides an additional profit of US$0.07/animal per day and increased milk and Minas frescal cheese fat without negative effects on productive parameters.

Detection of virulence-associated genes in pathogenic and commensal avian Escherichia coli isolates

Poultry colibacillosis due to Avian Pathogenic Escherichia coli (APEC) is responsible for several extra-intestinal pathological conditions, leading to serious economic damage in poultry production. The most commonly associated pathologies are airsacculitis, colisepticemia, and cellulitis in broiler chickens, and salpingitis and peritonitis in broiler breeders. In this work a total of 66 strains isolated from dead broiler breeders affected with colibacillosis and 61 strains from healthy broilers were studied. Strains from broiler breeders were typified with serogroups O2, O18, and O78, which are mainly associated with disease. The serogroup O78 was the most prevalent (58%). All the strains were checked for the presence of 11 virulence genes: 1) arginine succinyltransferase A (astA); ii) E.coli hemeutilization protein A (chuA); iii) colicin V A/B (cvaA/B); iv) fimbriae mannose-binding type 1 (fimC); v) ferric yersiniabactin uptake A (fyuA); vi) iron-repressible high-molecular-weight proteins 2 (irp2); vii) increased serum survival (iss); viii) iron-uptake systems of E.coli D (iucD); ix) pielonefritis associated to pili C (papC); x) temperature sensitive haemaglutinin (tsh), and xi) vacuolating autotransporter toxin (vat), by Multiplex-PCR. The results showed that all genes are present in both commensal and pathogenic E. coli strains. The iron uptake-related genes and the serum survival gene were more prevalent among APEC. The adhesin genes, except tsh, and the toxin genes, except astA, were also more prevalent among APEC isolates. Except for astA and tsh, APEC strains harbored the majority of the virulence-associated genes studied and fimC was the most prevalent gene, detected in 96.97 and 88.52% of APEC and AFEC strains, respectively. Possession of more than one iron transport system seems to play an important role on APEC survival.

Osteopontin splice variants expression is involved on docetaxel resistance in PC3 prostate cancer cells

Osteopontin (OPN) is a phosphoprotein that activates several aspects of tumor progression. Alternative splicing of the OPN primary transcript generates three splicing isoforms, OPNa, OPNb and OPNc. In this report, we investigated some cellular mechanisms by which OPN splice variants could mediate PC3 prostate cancer (PCa) cell survival and growth in response to docetaxel (DXT)-induced cell death. Cell survival before and after DXT treatment was analyzed by phase-contrast microscopy and crystal-violet staining assays. Quantitative real-time PCR and immunocytochemical staining assays were used to evaluate the putative involvement of epithelial-mesenchymal transition (EMT) and OPN isoforms on mediating PC3 cell survival. Upon DXT treatment, PC3 cells overexpressing OPNb or OPNc isoforms showed higher cell densities, compared to cells overexpressing OPNa and controls. Notably, cells overexpressing OPNb or OPNc isoforms showed a downregulated pattern of EMT epithelial cell markers, while mesenchymal markers were mostly upregulated in these experimental conditions. We concluded that OPNc or OPNb overexpression in PC3 cells can mediate resistance and cell survival features in response to DXT-induced cell death. Our data also provide evidence the EMT program could be one of the molecular mechanisms mediating survival in OPNb- or OPNc-overexpressing cells in response to DXT treatment. These data could further contribute to a better understanding of the mechanisms by which PCa cells acquire resistance to DXT treatment.

Familial amyloidotic polineuropathy and systemic lupus

Familial amyloidotic polineuropathy is a genetic disorder, leading to systemic amyloid deposits, manifested as sensory-motor and autonomic neuropathy. In the Portuguese classical form, the disease is evident at a young age, and causes death if no specific treatment is received. Variability in penetrance, age of onset and clinical course has been published; environmental and genetic factors are believed to contribute to this variability. The authors report a case of a 51-year-old white female, with a medical history of acquired angioedema, late-onset familial amyloidotic polineuropathy and systemic lupus erythemathosus. The authors consider that these associated diseases could modulate their expression.

Clinical significance, angiographic characteristics, and short-term outcomes in 30 patients with early coronary artery graft failure

BACKGROUND

Despite technical advances in coronary artery bypass grafting (CABG), early postoperative myocardial ischaemia still remains a challenging problem. The aim of this study was to determine the incidence, clinical features, angiographic characteristics, and management of early graft failure in the present CABG era.

METHODS

Between January 1997 and December 2002, 1731 patients underwent CABG at our institution. Coronary angiography was performed in patients with clinical evidence of early postoperative ischaemia (</=3 months). Thirty of these patients with graft failure constituted the population of this study.

RESULTS

Off-pump and on-pump CABG were almost evenly performed in these patients [n=16 (53%) and n=14 (47%) respectively]. Acute myocardial infarction and unstable angina were the leading indications for coronary angiography in the majority of patients [n=28 (93%)]. The most common cause of graft failure was occlusion / thrombosis [n=20 (67%)]. Percutaneous coronary intervention (PCI) was offered to the majority of patients [n=22 (73%)]. Of these patients, 14 underwent PCI to native coronary arteries, whereas eight underwent PCI to the culprit vessel. Three patients underwent reoperation, and five received medical management. Four patients (13%) died in hospital (two after redo CABG, one after unsuccessful PCI, and one patient managed medically). Two patients (7%) had nonfatal major complications (one non-ST-elevation myocardial infarction and one stroke).

CONCLUSION

Early graft failure generally presents as acute coronary syndrome. Graft occlusion/ thrombosis is the leading cause of ischaemia. Patients with graft failure can undergo PCI with a relatively low risk, but the need for redo CABG in associated with a high mortality. (Neth Heart J 2009;17:13-7.).

All-optical nonlinear switching cell made of photonic crystal

We analyze and propose a directional optical coupler embedded in photonic crystal, which is driven by an external command signal. Therefore, this switching cell can work in an all-optical switch. The switching method uses a low-power external command signal, inserted in the central coupling region, which acts as another waveguide. The switching process is based on the change from the bar state to the cross state due to the external command signal. In our simulations we used the plane wave expansion method, finite-difference time-domain method, and our own binary propagation method.

Chronic allograft dysfunction-is there a treatment?

BACKGROUND

The major causes of renal transplant loss are death and chronic allograft dysfunction (CAD). The aims of this study were to determine the incidence of CAD in our population and the relation between allograft survival and immunosuppressive regimens.

METHODS

We studied retrospectively 473 patients who received deceased donor kidney transplants with at least 1 allograft biopsy between January 1990 and May 2007. Clinical data included age, gender, biopsy data, and immunosuppression before and after kidney biopsy. Mean age was 45.4 +/- 12.7 years including 65% males with a mean follow-up of 6.7 +/- 4.5 years. CAD was observed in 177 of 473 biopsies: 48 patients showed interstitial fibrosis (IF); 101 chronic rejection (CR); 16 transplant glomerulopathy (TG); and 12, CR and TG. Mean follow-up since the discovery of the histologic feature was 60.5 +/- 50.5 months for IF; 38.3 +/- 40.8 for CR, and 18.2 +/- 19.2 for TG.

RESULTS

CAD, which was more common in younger patients (P = .03), correlated upon univariate and multivariate analysis with CKD stage 5d development (P < .001). Deposition of C4d in peritubular capillaries was more frequent among CAD patients (P = .004), an association with particular relevance to recipients with CR (P = .02) and TG (P < .001). When we analyzed CAD subpopulation, we observed a positive correlation between allograft survival and immunosuppression modification after biopsy. Substitution of sirolimus (40/177) was shown in univariate, multivariate and Cox regression analyses to be a renal protector (P < .002). Allograft survival was also correlated with initial mycophenolate mofetil versus azathioprine, (62/177) immunosuppression (P < .001).

CONCLUSION

CAD, a frequent histologic feature, may benefit from sirolimus conversion.

Specific IgG antibody response against antigens of Dirofilaria immitis and its Wolbachia endosymbiont bacterium in cats with natural and experimental infections

Sera from three groups of cats under different experimental conditions were studied by ELISA to assess the host's immune response against synthetic peptides derived from Dirofilaria immitis (Dipp) and against the surface protein of its endosymbiont, Wolbachia (WSPr). In experimentally infected cats (Group 1), an increase of IgG antibody against both Dipp and WSPr was observed from 2 months post-infection until the end of the study, 6 months post-infection. In experimentally infected cats, treated against infective larvae (Group 2), anti-Dipp IgG decreased dramatically from 4 months post-infection (3 months post treatment), showing very low values till the end of the study (6.5 months from infection, 5.5 months from treatment), while anti-WSP IgG increased constantly till the end of the study. Of 49 outdoor, asymptomatic cats exposed to a high risk of natural infection (Group 3), 9 were positive for anti-Dipp IgG and for a validated, in-clinic commercial antibody diagnostic kit for cats. Two cats were also found positive for circulating antigens of adult female worm. Anti-WSPr IgG were found in five of nine anti-Dipp IgG-positive sera and from eight ELISADipp-negative sera. Our results confirm the strong IgG response in heartworm infected cats and demonstrate the involvement of the Wolbachia endosymbiont in the immune reaction to the parasite both in experimentally infected cats and in cats exposed to a high risk of natural infection.

Groundwater radon, radium and uranium concentrations in Região dos Lagos, Rio de Janeiro State, Brazil

Ground water from Região dos Lagos, a coastal area of Rio de Janeiro state, was analysed for (226)Ra, (228)Ra, (222)Rn, (238)U, major ion concentrations, and physico-chemical parameters were also measured. Concentrations values ranged from <0.002 to 0.492 Bq l(-1) for (226)Ra, from <0.01 to 1.50 Bq l(-1) for (228)Ra and from < 1.0 x 10(-4) to 8.0 x 10(-2) Bq l(-1) for (238)U. Detectable (222)Rn concentrations (>3 Bq l(-1)) were found only in two samples. The spatial distribution of Ra concentration delineated one distinct area and some hot spots with high Ra concentration. Low pH value is the most important water parameter linked to high radium concentration. This is probably related to limited adsorption of radium on soil ferric oxides and hydroxides at low pH range. There was a significant correlation between uranium concentrations and electrical conductivity values, and also between uranium concentrations and concentrations of Ca, Mg, Na, K, and Cl, indicating sea water impact. Uranium concentrations were lower than maximum contaminant level for drinking water, whereas 17 out of the 88 ground water samples had levels of radium that exceeded the maximum contaminant level for tap water. The total annual effective dose for adult due to the water consumption reaches values up to 0.8 mSv.

Third-generation progestogen type influences hemostatic changes caused by oral contraceptives in Brazilian women

We compared the effects of two third-generation progestogens, desogestrel (DSG) and gestodene (GSD), on coagulation and fibrinolysis in Brazilian users of oral contraceptives (OCs). Forty-six women were evaluated before treatment and after six cycles of treatment. The coagulation, anticoagulant, and fibrinolytic systems were investigated. During the use of the DSG-containing OC, the activity of factors VII, VIII, IX, X, and XII increased significantly whereas the GSD-containing OC caused no changes in coagulation parameters. Concerning the anticoagulant pathways, the DSG-containing OC increased protein C levels and decreased total protein S levels, and the GSD-containing OC only decreased total protein S. Both OCs increased plasminogen activity, although the DSG-containing OC increased fibrin degradation products levels and decreased the tissue plasminogen activator antigen. In conclusion, we have found that in Brazilian women the effects of DSG and GSD on hemostatic parameters are different and, therefore, third-generation progestogens may not contribute equally to the thrombotic risk.

Goiter and hypothyroidism in two siblings due to impaired Ca(+2)/NAD(P)H-dependent H(2)O(2)-generating activity

We report herein the study of two siblings (DESM and DSM) with hypothyroidism, goiter, and positive perchlorate discharge tests (50% and 70%) in a family (M) with no history of consanguinity. Thyroid gland histology showed a predominance of hyperactive follicles, with high epithelial cells and variable colloid content. Thyroid peroxidase iodide oxidation (DESM, 1034; DSM, 1064 U/g protein) and albumin iodination (DESM, 16; DSM, 8 nmol I/mg protein) activities were within the normal range. Tg content was normal in both glands compared with that in diffuse toxic goiter (DESM, 28; DSM, 17; diffuse toxic goiter, 19 mg/g tissue), and Tg could be normally iodinated by thyroid peroxidase in vitro (DESM, 3.4; DSM, 4.3; diffuse toxic goiter, 6.3 nmol I/mg Tg). Thyroid cytochrome c reductase activities in these goiters were higher than that in paranodular tissues (DESM, 473; DSM, 567; paranodular tissues, 78 nmol NADP(+)/h/mg protein). However, thyroid NADPH oxidase activities were very low both in the particulate 3,000 x g (DESM, 4.8; DSM, 44; paranodular tissues, 224 nmol H(2)O(2)/h/mg protein) and in the particulate 100,000 x g fractions (DESM, 40; DSM, 47; paranodular tissues, 200 nmol H(2)O(2)/h/mg protein). Thus, a decreased Ca(2+)/NAD(P)H-dependent H(2)O(2) generation is the probable cause of the organification defect in these goiters.

Effects of two oral contraceptives, containing 30 or 20 microg of ethinyl estradiol in combination with gestodene, on blood coagulation and fibrinolysis in Brazilian women

OBJECTIVE

Blood coagulation and fibrinolytic variables were evaluated in 46 Brazilian women treated with either of two monophasic oral contraceptives (OC), containing 30 or 20 microg of ethinyl estradiol, and 75 microg of gestodene.

METHODS

The effects on procoagulants, anticoagulants, pro-fibrinolytics and antifibrinolytics and fibrin turnover were evaluated after treatment for six consecutive cycles, the impact of reduction of ethinyl estradiol dosage on these effects being assessed.

RESULTS

The OC containing 30 microg of ethinyl estradiol significantly increased the activities of factors VIII and X, whereas the one containing 20 microg of ethinyl estradiol caused no changes in clotting factors. Neither treatment altered fibrinogen levels or factor VII, IX or XII activity. There were no changes in antithrombin levels, but treatment with 30 microg ethinyl estradiol increased protein C levels and treatment with 20 microg decreased total protein S levels. Concerning the fibrinolytic parameters, both OCs increased plasminogen activity, whereas no changes in PAI-1, t-PA, alpha-2-antiplasmin or fibrin degradation products were observed. The reduction in ethinyl estradiol dosage from 30 microg to 20 microg eliminated the effects on factors VIII and X.

CONCLUSIONS

The results show that the OC studied did not cause sufficient changes to indicate that there may be a correlation between these laboratory alterations and clinical results. The lack of reports concerning the hemostatic effects of OCs on Brazilian women hinders comparison of the present data with those obtained for other ethnic groups, at different geographical locations, and emphasizes the importance of such a study for future epidemiological investigation of the prothrombotic effects of OCs in Brazilian women.

Participation of alpha-1 and alpha-2 adrenoceptors of the lateral hypothalamic area in water intake, and renal sodium, potassium and urinary volume excretion induced by central administration of angiotensin II

The circumventricular structures and the lateral hypothalamus (LH) have been shown to be important for the central action of angiotensin II (ANGII) on water and electrolyte regulation. Several anatomical findings have demonstrated neural connection between circumventricular structures and the LH. The present experiments were conducted to investigate the role of the alpha-adrenergic antagonists and agonistic injected into the LH on the water intake, sodium and potassium excretion elicited by injections of ANGII into the lateral ventricle (LV). The water intake was measured every 30 min over a period of 120 min. The sodium, potassium and urinary volume were measured over a period of 120 min in water-loaded rats. The injection of ANGII into the LV increased the water intake, which was reduced by previous injection of clonidine (an alpha-2-adrenergic agonist) into the LH. The injection of yohimbine (an alpha-2-adrenergic antagonist) and prazosin (an alpha-1-adrenergic antagonist) into the LH, which was done before injecting ANGII into the LV, also reduced the water intake induced by ANGII. The injection of ANGII into the LV reduced the sodium, potassium and urinary volume. Previous treatment with clonidine attenuated the action of ANGII in reducing the sodium, potassium and urinary volume, whereas previous treatment with yohimbine attenuated the effects of ANGII but with less intensity than that caused by clonidine. Previous treatment with prazosin increased the inhibitory effects of ANGII in those parameters. The injection of yohimbine and prazosin, which was done before the injection of clonidine, attenuated the effect of clonidine on the ANGII mechanism. The results of this study led us to postulate that when alpha-2-adrenergic receptors are blocked, the clonidine may act on the imidazoline receptors to produce its effects on the ANGII mechanism. We may also conclude that the LH is involved with circumventricular structures, which present excitatory and inhibitory mechanisms. Such mechanisms are responsible for regulating the renal excretion of sodium, potassium and water.

Effects of oral contraceptives in vaginal cytology

Many literature studies have shown that long-term use of oral contraceptives (OC) is associated with lack of protection of the epithelium of the uterine cervix. Forty-five patients, from 18 to 35 years old, users of two contraceptive formulations, of different estrogenic concentration, took part in this study as volunteers to evaluate the predisposition of the cervix to pathologies. The results found before OC use were 11% of Chlamydia trachomatis infection and 13% of HPV infection. These pathologies were correctly treated and after 5 months of OC use we found total remission of Chlamydia trachomatis infection and 4% of persistent HPV infection. These data lead us to conclude that the OC studied here interfered very little with the presented pathologic results. The risk factors that we considered relevant were: 1) age group (the patients that presented HPV and C. trachomatis infections were young university students); 2) lifestyle (most patients certified that they did not combine the use of barrier contraceptives with the use of OC); 3) multiple sexual partners; 4) low socioeconomic condition.

Thyroid peroxidase inhibition by Kalanchoe brasiliensis aqueous extract

Flavonoids are known inhibitors of thyroid peroxidase (TPO) and some are components of Kalanchoe brasiliensis, a plant used in popular medicine to treat tissue injuries, enlarged ganglia and peptic ulcer. As K. brasiliensis extract is currently used, the present study was designed to evaluate the effects of K. brasiliensis aqueous extract on TPO activity. We show here that TPO iodide-oxidation activity was significantly inhibited by K. brasiliensis aqueous extract and that TPO inhibition seems to be competitive, since the enzyme V(max) was unchanged and K(m) for iodide was significantly increased in the presence of the plant extract. Furthermore, TPO inhibitory activity produced by K. brasiliensis extract was unchanged after boiling or by incubation with hepatic enzymes (activated S9 fraction), suggesting that at least the antithyroid component of this plant infusion could probably reach systemic circulation. We also report that K. brasiliensis aqueous extract is able to scavenge H(2)O(2), in vitro. As H(2)O(2) is an essential TPO cofactor, it is possible that the H(2)O(2) trapping effect of K. brasiliensis may be responsible, at least in part, for the inhibition of the iodide-oxidation reaction catalysed by this enzyme. Thus, K. brasiliensis aqueous extract has antithyroid effects in vitro, suggesting that its chronic consumption could contribute to the development of goitre and hypothyroidism, mainly in areas of low iodine intake.

Thyroid peroxidase activity is inhibited by amino acids

Normal in vitro thyroid peroxidase (TPO) iodide oxidation activity was completely inhibited by a hydrolyzed TPO preparation (0.15 mg/ml) or hydrolyzed bovine serum albumin (BSA, 0.2 mg/ml). A pancreatic hydrolysate of casein (trypticase peptone, 0.1 mg/ml) and some amino acids (cysteine, tryptophan and methionine, 50 microM each) also inhibited the TPO iodide oxidation reaction completely, whereas casamino acids (0.1 mg/ml), and tyrosine, phenylalanine and histidine (50 microM each) inhibited the TPO reaction by 54% or less. A pancreatic digest of gelatin (0.1 mg/ml) or any other amino acid (50 microM) tested did not significantly decrease TPO activity. The amino acids that impair iodide oxidation also inhibit the TPO albumin iodination activity. The inhibitory amino acids contain side chains with either sulfur atoms (cysteine and methionine) or aromatic rings (tyrosine, tryptophan, histidine and phenylalanine). Among the amino acids tested, only cysteine affected the TPO guaiacol oxidation reaction, producing a transient inhibition at 25 or 50 microM. The iodide oxidation inhibitory activity of cysteine, methionine and tryptophan was reversed by increasing iodide concentrations from 12 to 18 mM, while no such effect was observed when the cofactor (H2O2) concentration was increased. The inhibitory substances might interfere with the enzyme activity by competing with its normal substrates for their binding sites, binding to the free substrates or reducing their oxidized form.

Characterization and radiation resistance of new isolates of Rubrobacter radiotolerans and Rubrobacter xylanophilus

In this study we characterized new strains of the slightly thermophilic species Rubrobacter radiotolerans and the thermophilic species Rubrobacter xylanophilus, both of which were previously represented only by the type strains isolated, respectively, from Japan and the United Kingdom. The new isolates were recovered from two hot springs in central Portugal after gamma irradiation of water and biofilm samples. We assessed biochemical characteristics, performed DNA-DNA hybridization, and carried out 16S rDNA sequence analysis to demonstrate that the new Rubrobacter isolates belong to the species R. radiotolerans and R. xylanophilus. We also show for the first time that the strains of R. xylanophilus and other strains of R. radiotolerans are extremely gamma radiation resistant.

[Congenital malformations of the upper limb. General considerations]

The authors develop same general considerations about history, embryology, classification and treatment of congenital upper limb anomalies. They review 62 clinical cases of operated patients in Unit Plastic and Reconstructive Surgery of Santa Maria Hospital and show same cases.

[Microsurgical reconstruction of the head and neck: experience of 63 free flaps]

The authors present the experience of 63 clinical cases of microsurgical reconstruction of the head and neck. These reconstructions were accomplished by different microvascular free flaps which were selected according to the type, size and location of the defects. Fasciocutaneous, osteofasciocutaneous, adipofascial, myo, myocutaneous, myosseous, jejunum and great omentum flaps were applied. The etiology was traumatic in 10 cases, tumoral in 41 cases, congenital in 7 cases, iatrogenic in 3 cases and infectious in 2 cases. The reconstructed anatomical regions were the scalp in 6 cases, the skull base in 1 case, the orbit in 3 cases, the nose in 1 case, the hemiface in 7 cases, the lips in 1 case, the intraoral cavity in 21 cases, the mandible in 8 cases, the intraoral cavity plus mandible in 11 cases and the cervical esophagus in 1 cases. An analysis was made of surgical times, selection and survival rate of the free flaps and the morphofunctional quality of the reconstructions. Considering the good quality of reconstructions, the amelioration of quality of life and the low morbidity in these patients, microvascular free flaps are considered a first choice technique for head and neck reconstruction when the size and location of the defect prevents the use of local flaps.

[Pneumothorax and pulmonary intersticial emphysema: treatment with selective bronchial occlusion and high frequency ventilation]

OBJECTIVE: Our purpose was to report the use of selective bronchial occlusion with a balloon catheter, associated with high frequency ventilation for a successful treatment of a persistent left hypertensive pneumothorax associated with left bronchopleural fistula and severe bilateral pulmonary intersticial emphysema.METHODS: A newborn infant of 20 hours of age was referred to our ICU for treatment of severe respiratory distress and hemodynamic failure after spontaneous hypertense left pneumothorax. Despite being submitted to conventional mechanical ventilation, volume resuscitation and vasoactive drugs infusion, the patient worsened. Therefore, he underwent selective occlusion of the main left bronchus, a measure that can be effective to interrupt gas flow to the affected lung in situations like lung injury with air leak. In order to avoid worsening intersticial emphysema and air leak, high frequency ventilation was associated. This method is characterized by very low tidal volume, lower than the rest functional capacity, and is indicated in acute respiratory failure associated with air leak syndrome.RESULTS: Selective left main bronchus occlusion and high frequency ventilation were successfully used to treat the patient who, after that, presented a favorable outcome with full hemodynamic and respiratory recovery.CONCLUSION: Selective left main bronchus occlusion permitted mechanical ventilation of the contralateral side and high frequency ventilation allowed adequate oxygenation and ventilation maintenance with decrease of the risk of lung injury and also allowed recovery from the interstitial emphysema.

[Auto-PEEP effects on respiratory mechanics and blood gases in mechanically ventilated patients]

OBJECTIVE: The purpose of this study was to examine the auto-PEEP incidence and magnitude and the relationship between its reductions and changes in respiratory mechanics and gas exchanges in mechanically ventilated patients addmited in an Intensive Care Unit.METHODS: A prospective study was conducted in seventeen infants undergoing mechanical ventilation due to respiratory or neuromuscular diseases. We have measured blood gases, mean airway pressure, tidal volume, compliance, resistance and time constants of the respiratory system and monitored pressure, flow and volume waveforms and pressure-volume and flow-volume loops.RESULTS: Thirteen patients or 76% developed auto-PEEP and the reduction of its magnitude (from 5.4 -/+ 3.2 to 4.1 -/+ 2.6 cmH2O, p<0.01) showed association to mean airway pressure decrease (from 10.2 -/+ 3.1 to 9.3 -/+ 2.3 cmH2O, p<0.01), tidal volume (from 45.3 -/+ 19.1 to 51.3 -/+ 22.9 ml, p<0.01) and corrected compliance increase (1.02 -/+ 1.20 to 1.13 -/+ 1.41 ml/cmH2O/kg, p=0.05). Expiratory resistance remained unchanged (from 15.0 -/+ 8.6 to 15.7 -/+ 9.4 cmH2O/l/sec/kg, p=0.06). Arterial blood gases showed pH increase (from 7.37 -/+ 0.12 to 7.42 -/+ 0.05, p<0.05) and PCO2 and PO2 decrease (from 40.1 -/+ 11.1 mmHg to 33.1 -/+ 7.4 mmHg, p<0.01 and 65.0 -/+ 13.9 to 58.0 -/+ 12.6 mmHg, p<0.01 respectively).CONCLUSIONS: Auto-PEEP reduction was associated with pulmonary mechanics and blood gases improvement. Knowledge of auto-PEEP presence and magnitude allowed to respiratory system compliance and time constants correction, providing accurate index of the pulmonary mechanics.

[Traumatic lesions of the brachial plexus]

The diagnosis and treatment of brachial plexus lesions have developed remarkably in recent decades. The knowledge of anatomy and histology, the physiology of lesions, and the definition of ideal conditions for nervous regeneration created the basic support, which caused the use of microsurgery to improve the surgical results of these lesions. On the other hand, patients used to be seen by specialists from different fields, no one saw the need to join efforts in order to achieve a multidisciplinary approach. These lesions essentially affect young males who belong to a social and professional environment in which motorcycles are usually used as their main means of transport. The correct diagnosis of this histology is based on a clinical analysis of each case, which requires separate evaluations in some instances. Only thus is it possible to establish a therapeutic plan in which physiotherapy plays a permanent and vital role. Complementary studies always included electromyography, which seems to be a useful guide to the progression of the lesions. For operated cases, cervical myelography, ultrasonography and magnetic resonance seem to be a useful aid to characterise the lesions and define the prognosis. The therapeutic decisions must be early and convenient. We found all types of nervous lesions and performed various types of surgery with microsurgery techniques, mostly using nerve grafts. In the case of infra-ganglion lesions. nerve grafts were used to neurotize peripheral nerves from proximal stumps. In case of supra-ganglionic complete lesions, we used the accessory spinal nerve, the motor branches of the cervical plexus and the intercostal nerves. In relation to peripheral neurolization, we tried to establish a certain order, beginning with reinnervation of muscles responsible for proximal function.

Deinococcus geothermalis sp. nov. and Deinococcus murrayi sp. nov., two extremely radiation-resistant and slightly thermophilic species from hot springs

Strains of Deinococcus geothermalis sp. nov. were isolated from the hot spring and runoff at Agnano, Naples, Italy, and from the hot spring at São Pedro do Sul in central Portugal, while strains of Deinococcus murrayi sp. nov. were isolated from the hot springs at São Pedro do Sul, São Gemil, and Alcafache in central Portugal. The strains of D. geothermalis and D. murrayi produce orange-pigmented colonies and have an optimum growth temperature of about 45 to 50 degrees C. The type strains of the two new species are extremely gamma radiation resistant. The fatty acids of these new species are primarily branched-chain fatty acids. The two new species can be distinguished from each other by the lower pH range of D. geothermalis than of D. murrayi, by their fatty acid compositions, and by several biochemical parameters, including the ability of D. geothermalis to grow in minimal medium without yeast extract. 16S rRNA gene sequencing also showed that the isolates constitute two species and that these species are distinct from the other species of the genus Deinococcus. The type strain of D. geothermalis is AG-3a (= DSM 11300), and the type strain of D. murrayi is ALT-1b (= DSM 11303).

Saphenous vein graft aneurysm presenting as a large mediastinal mass compressing the right atrium

A patient with a large saphenous vein graft aneurysm is described. This case illustrates the role of magnetic resonance imaging and cardiac catheterization in patients with a mediastinal mass and history of coronary bypass surgery.

Sinus of Valsalva aneurysm presenting as myocardial infarction during dobutamine stress test

We report a patient with an undiagnosed left sinus of Valsalva aneurysm who, during a dobutamine stress test, had myocardial injury and subsequent infarction. Cardiac catheterization revealed an expanding sinus of valsalva aneurysm compressing the circumflex coronary artery. The clinical manifestations of sinus of Valsalva aneurysm are discussed. This report heightens awareness of the possible effects of the pharmacologic stress test.

Computer-aided comparison of protein electrophoretic patterns for grouping and identification of heterotrophic bacteria from mineral water

The microflora of a natural mineral water was studied immediately after bottling (T0) and after 7 d storage (T7) during 6 months, and isolates were clustered by SDS-PAGE of whole-cell protein profiles. Isolates from each cluster were further characterized by API 20NE, fatty acid composition and quinone profiles. The numerical analysis of the electrophoregrams of all bacteria isolated from the mineral water formed 15 clusters and five unclustered strains. Except for five minor clusters, all clusters were composed of strains isolated over several months. The numerical analysis of the electrophoregrams of bacteria isolated immediately after bottling formed 15 clusters while after 7 d storage only four of these populations could be isolated, indicating the populations present in the mineral water were stable and that changes occurring after bottling probably resulted from a selection process. Only one unclustered strain was identified simultaneously by all the systems, as Sphingomonas paucimobilis. The monitoring of the aquifer and the bottling system, and the construction of a large database with bacteria of the autochthonous flora allows the detection of alterations in the aquifer by changes in the microflora.

Subarachnoid hemorrhage simulating myocardial infarction

We describe a patient with a subarachnoid hemorrhage that presented with electrocardiographic evidence of transmural myocardial infarction. The patient was found to have normal coronaries and on autopsy revealed generalized myocytolysis with no evidence of transmural myocardial infarction. This case illustrates the value of acute coronary angiography in patients with altered mental status and suspected myocardial infarction.