Avaliação morfométrica e estereométrica dos tecidos periodontais de ratos imunossuprimidos por Tracolimus (FK506)

Pós-graduação em Odontologia - FOAR

Atividade antibacteriana de plantas medicinais frente á bactérias multirresistentes e a sua interação com drogas antimicrobianas

O controle de micro-organismos infecciosos multirresistentes às vezes é ineficaz mesmo com o desenvolvimento de novos antibióticos. Diversos extratos de plantas medicinais têm efeitos antimicrobianos o que pode representar uma alternativa terapêutica para doenças infecciosas, principalmente quando associados aos antibióticos de uso clínico. O objetivo do trabalho foi avaliar a atividade antibacteriana de plantas medicinais sobre bactérias multirresistentes e os efeitos de sua interação com drogas antimicrobianas. Foi determinada a atividade antibacteriana de extratos e frações das plantas Eleutherine plicata (marupazinho), Geissospermum vellosii (pau-pereira) e Portulaca pilosa (amor-crescido) frente a isolados de Staphylococcus aureus Oxacilina Resistente (ORSA) e de Pseudomonas aeruginosa multirresistente, provenientes de processos clínicos humanos, assim como a interação destes produtos vegetais com drogas antimicrobianas de uso clínico. A atividade antibacteriana foi determinada pelo método de disco difusão em ágar Muller Hinton e a Concentração Inibitória Mínima (CIM) pela técnica de microdiluição em placas utilizando caldo Muller Hinton como meio de cultura e resazurina a 0,01% como revelador de crescimento bacteriano. Os extratos e frações foram testados nas concentrações de 500, 250, 125, 62,5, 31,2 e 16,2 μg/mL dissolvidos em DMSO a 10%. As plantas E. plicata e G. vellosii demonstraram atividade contra os isolados ORSA com CIM de 125 μg/mL, enquanto que P. pilosa teve ação sobre os isolados de P. aeruginosa multirresistentes com CIM de 250 μg/mL. Ocorreram 25% de sinergismo e apenas 5% de antagonismo entre as 120 interações de produtos vegetais e drogas antimicrobianas testadas. Frente aos isolados ORSA houve sinergismo com as drogas ciprofloxacina, clindamicina e vancomicina tanto com os derivados de E. plicata como os de G. vellosii. Os produtos de P. pilosa potencializaram a ação das drogas aztreonam, cefepime e piperacilina+tazobactam frente aos isolados de P. aeruginosa multirresistentes. Os resultados comprovaram o potencial das plantas E. plicata, G. vellosii e P. pilosa no controle de infecções bacterianas envolvendo fenótipos multidrogas resistentes (MDR) e que a sua interação com drogas antibacterianas pode representar uma nova alternativa na terapia destas infecções.

Estudo in vitro do efeito da interferência por RNA (RNAi) na replicação do vírus da hepatite C

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Plantas medicinais: indicação popular de uso no tratamento de hipertensão arterial sistêmica (HAS)

The aim of this study is to investigate the spontaneous use of medicinal plants by volunteer patients in the treatment of hypertension and to determine the most used plants in this situation. Data were collected through a questionnaire and a semi-structured guided interview applied to patients from a health center in the Midwest region of the state of Sao Paulo, Brazil. Quantitative analysis identified a high number of hypertensive patients spontaneously using herbal treatment. The referred plants were identified by the Herbarium Botu and researched in the literature as to their therapeutic actions. The biggest mistake was observed in the misuse of the Bilberry for the treatment of hypertension, which reveals that health professionals and the community in general should be more careful. As a result we have published an informative booklet, with emphasis on hypertension concepts and on the use of medicinal plants as an alternative therapy method for this disease in order to provide scientific knowledge and scientific research evidence to this practice.

Impact of pediatric epilepsy surgery on intellectual efficiency

Introduction. Epilepsy surgery may be a promising alternative therapy for seizure control in patients with refractory seizures, resistant to medication. Cognitive outcome is another important factor in favor of the surgical decision. Aim. To investigate the correlation between seizure outcome and cognitive outcome after epilepsy surgery in a pediatric population. Patients and methods. A total of 59 pediatric patients were retrospectively assessed with the WISC-III (Full Scale, Verbal Scale and Performance Scale) before and, at least, 6 months after surgery. Patients were divided into two groups according whether or not improvement of seizure control after surgery. Data collected for each child included: epileptic syndrome, etiology, age at epilepsy onset, duration of epilepsy and seizure frequency. Results. Comparison using a MANOVA test revealed significant differences across pre-operative Full Scale, Verbal Scale and Performance Scale (p = 0.01) with seizure reduction group performing better than no seizure reduction group. Seizure improvement group achieved significant Performance Scale improvement (p = 0.01) and no seizure improvement group showed significant Verbal Scale worsened after surgery (p = 0.01). Conclusions. Our results suggest that the success of the epilepsy surgery in childhood when the seizure control is achieved may also provide an improvement in the Performance Scale whereas the seizure maintenance may worsen the Verbal Scale.

Therapeutic use of a cationic antimicrobial peptide from the spider Acanthoscurria gomesiana in the control of experimental candidiasis

Background: Antimicrobial peptides are present in animals, plants and microorganisms and play a fundamental role in the innate immune response. Gomesin is a cationic antimicrobial peptide purified from haemocytes of the spider Acanthoscurria gomesiana. It has a broad-spectrum of activity against bacteria, fungi, protozoa and tumour cells. Candida albicans is a commensal yeast that is part of the human microbiota. However, in immunocompromised patients, this fungus may cause skin, mucosal or systemic infections. The typical treatment for this mycosis comprises three major categories of antifungal drugs: polyenes, azoles and echinocandins; however cases of resistance to these drugs are frequently reported. With the emergence of microorganisms that are resistant to conventional antibiotics, the development of alternative treatments for candidiasis is important. In this study, we evaluate the efficacy of gomesin treatment on disseminated and vaginal candidiasis as well as its toxicity and biodistribution. Results: Treatment with gomesin effectively reduced Candida albicans in the kidneys, spleen, liver and vagina of infected mice. The biodistribution of gomesin labelled with technetium-99 m showed that the peptide is captured in the kidneys, spleen and liver. Enhanced production of TNF-alpha, IFN-gamma and IL-6 was detected in infected mice treated with gomesin, suggesting an immunomodulatory activity. Moreover, immunosuppressed and C. albicans-infected mice showed an increase in survival after treatment with gomesin and fluconazole. Systemic administration of gomesin was also not toxic to the mice Conclusions: Gomesin proved to be effective against experimental Candida albicans infection. It can be used as an alternative therapy for candidiasis, either alone or in combination with fluconazole. Gomesin's mechanism is not fully understood, but we hypothesise that the peptide acts through the permeabilisation of the yeast membrane leading to death and/or releasing the yeast antigens that trigger the host immune response against infection. Therefore, data presented in this study reinforces the potential of gomesin as a therapeutic antifungal agent in both humans and animals.

Molekulare Grundlagen der Immunkontrolle des murinen Cytomegalovirus in Gegenwart viruskodierter Immunevasine

Die Kontrolle der Infektion mit dem humanen Cytomegalovirus (HCMV) wird primär durch antivirale CD8 T-Zellen vermittelt. Während der Koevolution zwischen Virus und Wirt wurden Immunevasionsmechanismen entwickelt, die direkt die Expression der Peptid-MHC-Klasse-I-Komplexe an der Zelloberfläche beeinflussen und es dem Virus ermöglichen, der Immunkontrolle des Wirtes zu entkommen. Da HCMV und das murine CMV (mCMV) zum Teil analoge Strategien zur Modulation des MHC-Klasse-I-Antigen-Präsentationswegs entwickelt haben, wurde in der vorliegenden Arbeit auf das experimentelle Modell mit mCMV zurückgegriffen. Die für die Immunevasion verantwortlichen Genprodukte m04/gp34, m06/gp48 und m152/gp40 werden aufgrund ihres regulatorischen Einflusses auf die Antigenpräsentation als vRAPs (viral regulators of antigen presentation) bezeichnet. Diese interferieren mit dem Transport Peptid-beladener MHC-Klasse-I-Moleküle und reduzieren in ihrer konzertierten Wirkung die Präsentation viraler Peptide an der Zelloberfläche.rnDie Transplantation hämatopoietischer Zellen nach Immunoablation stellt eine etablierte Therapieform bei malignen hämatologischen Erkrankungen dar. Zwischen Immunoablation und der Rekonstitution des Immunsystems sind die Empfänger der transferierten Zellen stark immunsupprimiert und anfällig für eine CMV-Erkrankung bei Reaktivierung des Virus. Neben der Gabe antiviraler Medikamente ist der adoptive Transfer antiviraler CD8 T-Zellen eine vielversprechende Therapiemöglichkeit, um reaktivierende CMV zu kontrollieren, bis das körpereigene Immunsystem wieder funktionsfähig ist. Obwohl im murinen Modell sehr wohl etabliert, stellen im humanen System die eingeschränkte Wirkung und die Notwendigkeit der konsequenten Gabe hoher Zellzahlen gewisse logistische Schwierigkeiten dar, welche die Methode bisher von der klinischen Routine ausschließen.rnDas murine Modell sagte eine Rolle von IFN-γ voraus, da Depletion dieses Zytokins zu einer verminderten Schutzwirkung gegen die mCMV-Infektion führt.rnIm ersten Teil dieser Arbeit sollte ein möglicher inhibitorischer Effekt von m04 auf m152 untersucht werden, der bei der Rekombinanten Δm06W beobachtet wurde. Mit neu generierten Viren (Δm06L1+2) konnte dieser Effekt allerdings nicht bestätigt werden. Bei Δm06W fehlte jedoch eine höher N-glykosylierte Isoform des m152-Proteins. Um zu untersuchen, ob die N-Glykosylierung von m152 für seine Funktion notwendig ist, wurde ein rekombinantes Virus generiert, das in Folge einer Deletion aller 3 N-Glykosylierungssequenzen nur eine nicht-glykosylierte Isoform des m152-Proteins bilden kann. In Übereinstimmung mit der zwischenzeitlich publizierten Kristallstruktur das Komplexes von m152 und dem Liganden RAE-1 des aktivierenden NK-Zellrezeptors NKG2D konnte erstmals gezeigt werden, dass die Funktionen von m152 in der adaptiven und in der angeborenen Immunität auch von der nicht N-glykosylierten Isoform wahrgenommen werden können.rnIm zweiten Teil der Arbeit sollte mit Hilfe eines Sets an vRAP Deletionsmutanten der Einfluss von IFN γ auf die einzeln oder in Kombination exprimierten vRAPs untersucht werden. Es zeigte sich, dass Vorbehandlung der Zellen mit IFN-γ die Antigenprozessierung nach Infektion stark erhöht und die vRAPs dann nicht mehr in der Lage sind, die Präsentation aller Peptid-beladener MHC-Klasse-I-Komplexe zu verhindern. Des Weiteren konnte gezeigt werden, dass vorher nicht-schützende CD8 T-Zellen Schutz vermitteln können, wenn das Gewebe der Rezipienten konstitutiv mit IFN-γ versorgt wird. Die zusätzliche Gabe von IFN-γ stellt daher eine vielversprechende Möglichkeit dar, den adoptiven Transfer als Therapie in der klinischen Routine einzusetzen.

Percutaneous aortic valve replacement for severe aortic stenosis in high-risk patients using the second- and current third-generation self-expanding CoreValve prosthesis: device success and 30-day clinical outcome

OBJECTIVES: We sought to determine both the procedural performance and safety of percutaneous implantation of the second (21-French [F])- and third (18-F)-generation CoreValve aortic valve prosthesis (CoreValve Inc., Irvine, California). BACKGROUND: Percutaneous aortic valve replacement represents an emerging alternative therapy for high-risk and inoperable patients with severe symptomatic aortic valve stenosis. METHODS: Patients with: 1) symptomatic, severe aortic valve stenosis (area <1 cm2); 2) age > or =80 years with a logistic EuroSCORE > or =20% (21-F group) or age > or =75 years with a logistic EuroSCORE > or =15% (18-F group); or 3) age > or =65 years plus additional prespecified risk factors were included. Introduction of the 18-F device enabled the transition from a multidisciplinary approach involving general anesthesia, surgical cut-down, and cardiopulmonary bypass to a truly percutaneous approach under local anesthesia without hemodynamic support. RESULTS: A total of 86 patients (21-F, n = 50; 18-F, n = 36) with a mean valve area of 0.66 +/- 0.19 cm2 (21-F) and 0.54 +/- 0.15 cm2 (18-F), a mean age of 81.3 +/- 5.2 years (21-F) and 83.4 +/- 6.7 years (18-F), and a mean logistic EuroSCORE of 23.4 +/- 13.5% (21-F) and 19.1 +/- 11.1% (18-F) were recruited. Acute device success was 88%. Successful device implantation resulted in a marked reduction of aortic transvalvular gradients (mean pre 43.7 mm Hg vs. post 9.0 mm Hg, p < 0.001) with aortic regurgitation grade remaining unchanged. Acute procedural success rate was 74% (21-F: 78%; 18-F: 69%). Procedural mortality was 6%. Overall 30-day mortality rate was 12%; the combined rate of death, stroke, and myocardial infarction was 22%. CONCLUSIONS: Treatment of severe aortic valve stenosis in high-risk patients with percutaneous implantation of the CoreValve prosthesis is feasible and associated with a lower mortality rate than predicted by risk algorithms.

Antimicrobial effect of Artemisia species on Pseudomonas aeruginosa

Antibiotic resistance has emerged as a severe problem in hospital-acquired infectious disease. The Gram-negative bacterium Pseudomonas aeruginosa is found to cause secondary infection in immune-compromised patients. Unfortunately, it is resistant to virtually all β-lactam antibiotics such as penicillin, cephalosporin and others. Researchers are seeking for new compounds to treat several antibiotic-resistant bacterial strains. Artemisia plant extracts are commonly used for their therapeutic properties by natives throughout dry regions of North and South America. Here, they are administered as an alternative medicine for stomach problems and other complex health issues. In this study, the antimicrobial effects of plant extracts from several Artemisia species as well as compounds dehydroleucodine and dehydroparishin-B (sesquiterpenes derived specifically from A. douglasiana) were used as treatments against the pathogenicity effects of P. aeruginosa. Results showed that both compounds effectively inhibit the secretion of LasB elastase, biofilm formation and type III secretion, but fail to control LasA protease. This is a significant observation because these virulent factors are crucial in establishing P.aeruginosa infection. The results from this study signify a plausible role for future alternative therapy in the biomedical field, which recommends DhL and DhP can be studied as key compounds against bacterial infections of Pseudomonas aeruginosa.

An overview of the effect of probiotics and exercise on mood and associated health conditions

The present paper provides a review of the current knowledge relating to the health benefits of probiotics, specially focused on the effects they may have together with physical exercise on mood disorders and related chronic medical conditions. With both these conditions being a substantial contributor to the global disease burden any alternative therapy must be considered. Probiotics influence the gut microbiota through a complex network of events which can influence mechanisms leading to development of mood disorders such as depression and anxiety. Similarly, through a complex interaction between psychological and neurobiological mechanisms, exercise has been found to play a key role in mood enhancement.

A Ortodontia e aparelhos intra orais no tratamento da SAHOS (Sindrome da Apneia e Hipopneia Obstrutiva do Sono)

A síndrome da apneia e hipopneia obstrutiva do sono (SAHOS) é uma patologia que atinge cerca de 4% da população adulta, é uma doença crónica, progressiva, com alta morbilidade e mortalidade. A apneia do sono e o ronco têm despertado a atenção da área da saúde devido às inúmeras comorbilidades associadas. Esta síndrome é caracterizada por obstrução parcial ou total das vias aéreas superiores durante o sono e manifesta-se como uma redução (hipopneia) ou cessação (apneia) do fluxo aéreo. A queixa habitual dos pacientes além dos problemas sociais como ronco e a hipersonolência diurna, são a preocupação com outros quadros que esta patologia pode desencadear, como insuficiência cardíaca e hipertensão pulmonar. O tratamento da apneia obstrutiva do sono é multidisciplinar e indispensável, podendo ser realizado de diversas formas, tanto conservadoras como cirúrgicas, dependendo de inúmeros fatores como a gravidade da doença, as alterações anatómicas das vias aéreas superiores, idade e condições sistémicas do paciente. Os aparelhos intra orais têm sido usados durante anos, no tratamento da SAHOS como controle da obstrução das vias aéreas superiores. A terapia com aparelhos intraorais é simples e reversível. O sucesso do tratamento com aparelhos intra orais para o ronco e SAHOS leve e moderada é comprovado pela grande maioria dos estudos. A facilidade de uso, manutenção e conforto quando comparados a outros tratamentos faz com que os aparelhos intrabucais sejam considerados de fácil aceitação pelos pacientes. Através de uma revisão de literatura discutiu-se o uso de aparelhos intrabucais para o tratamento dessa patologia, destacando a eficácia e as limitações dessa terapia, os principais sintomas clínicos, os principais efeitos colaterais oclusais, o grau de colaboração e o índice de satisfação dos pacientes. Foi possível concluir que aparelhos intrabucais de avanço mandibular estão amplamente indicados para o tratamento do ronco e da SAHOS como terapia principal, ou alternativa naqueles pacientes que não podem suportar a terapia da pressão positiva das vias aéreas e que para o sucesso do tratamento é fundamental uma equipe multidisciplinar, incluindo um Médico Dentista e a colaboração do paciente.

Resetting SETD2/H3K36ME3 deficiency in advanced systemic mastocytosis

Systemic Mastocytosis (SM) is a hematological disorder characterized by abnormal proliferation of mast cells in various organs, ranging from indolent variants to advanced entities with poor prognosis. The KIT D816V gene mutation drives mast cell growth, but its presence alone is not fully transforming. The SETD2 gene, responsible for maintaining genomic integrity, is often impaired in advanced SM (advSM), leading to reduced expression of histone marker H3K36Me3. Proteasome inhibitors are effective in restoring SETD2 function and suppressing mast cell growth, offering an alternative therapy for patients resistant to tyrosine kinase inhibitors. Aberrant expression of Plk1 and Aurora kinase A correlates with SETD2 loss and can be targeted with inhibitors like alisertib and volasertib, leading to reduced cell growth and apoptosis. Additionally, inhibition of Wee1 enhances apoptosis and reduces colony growth in SM cells. Molecular diagnostic techniques like droplet digital polymerase chain reaction (ddPCR) offer a less invasive and reliable method for detecting the D816V mutation in peripheral blood, and efforts to standardize molecular assays across laboratories show promising reproducibility. Overall, this research provides new insights into the mechanisms of advanced SM, identifies potential therapeutic targets, and validates molecular diagnostic tools for SM diagnosis.

Alternative regimens for prostate cancer treatment using radiation therapy

Purpose/Objective: The purpose of this work was to determine biologically equivalent alternative regimens for the treatment of prostate cancer using External Beam Radiotherapy (EBRT) and Low Dose-Rate Brachytherapy (LDRBT) with 125I implants and to evaluate the sensitivity of these regimens to different sets of radiobiological parameters of the Linear-Quadratic (LQ) model.

Longer survival for patients with alternative lengthening of telomeres (ALT) glioblastoma multiforme is due to a less aggressive phenotype and not to improved response to adjuvant therapy

Introduction: The Alternative Lengthening of Telomeres (ALT) mechanism is a significant prognostic factor for longer survival in patients with GBM, irrespective of age. The reasons for this are unknown. We considered two possibilities; firstly that ALT identifies a subset of less aggressive GBMs, or alternatively, a group of tumours that respond more favourably to adjuvant therapy. Methods: ALT was determined by staining for ALT Associated PML Bodies (APBs) in archival tissue in a retrospective analysis of 573 GBM patients. IDH1 mutation was determined by immunohistochemistry in a subset of these. Results: We identified the presence of the telomerase-independent ALT in 15% of GBM patients and found that it correlated with survival (22% of ALT patients survive more than 2 years compared to 9% for non-ALT). This survival advantage was independent of surgery type (biopsy or full resection) and treatment (radiotherapy and chemotherapy). Interestingly ALT conferred a significant survival advantage for patients who only received surgery (13.3 months compared to 5.5 months) (19% vs 1% .2 year survival). This survival benefit was also observed in GBM patients who received surgery and radiotherapy (18.5% vs 2.4%. 2 year survival), but less so for chemotherapy (21% vs 17% . 2 year survival). For the ALT patients the fraction surviving more than 2 years did not improve significantly with adjuvant therapy. IDH1 mutation also associated with ALT. Conclusions: These data indicate ALT+ tumours are biologically distinct and associated with improved patient survival, probably due to less aggressive/invasive growth. However they respond poorly to current adjuvant treatment and therefore new therapies are urgently needed for this group.