Antimicrobial effect of a local release system containing metronidazole against a Porphyromonas gingivalis biofilm.

The aim of this study was to evaluate a semi-solid system containing metronidazole (MDZ) in presence of challenging conditions for drug release, as well its antimicrobial effect against Porphyromonas gingivalis biofilm. Biofilms grown in culture medium were exposed to a formulation containing MDZ or its vehicle. After 24, 48, and 72 h, biofilm viability were analyzed while MDZ was quantified in culture medium and buffer solution (control). MDZ formulation reduced bacterial viability when compared to control groups. The vehicle formulation also affected bacterial viability in relation to control at all periods. Culture medium impaired MDZ release compared to buffer solution at 24 h. The semi-solid system reported herein is able to release MDZ and maintain its levels at concentrations that control viability of P. gingivalis in 1- to 3-day-old biofilms.

Local antibiotic delivery in periodontitis: drug release and its effect on supragingival biofilms.

The effect of a drug-delivery system containing antibacterial metronidazole (MDZ) prescribed for periodontitis on supragingival biofilm was evaluated, and possible interference by this biofilm in the drug release profile was investigated. Streptococcus mutans biofilms were grown and exposed to a controlled-release formulation of MDZ or the same formulation without MDZ (vehicle control). Untreated biofilms were used as a negative control (NC). Biofilms and culture medium (containing detached cells) were collected 24, 48, 72, and 96 h after first exposure to treatments. The biomass of the MDZ group was lower than that of the NC group at all times. Although MDZ yielded low drug-release rates in the presence of the biofilm, it was sufficient for reducing viability for 24 h and affecting bacterial metabolism for 48 h. These results suggest that MDZ appears to destabilize supragingival biofilm. This biofilm may interfere with MDZ release from the formulation.

Development of topical functionalized formulations added with propolis extract: stability, cutaneous absorption and in vivo studies.

Propolis, which is a natural product widely consumed in the folk medicine, is a serious candidate to be applied topically due to its outstanding antioxidant properties. So, the purpose of this study was to develop stable topical formulations added with propolis extract in an attempt to prevent and/or treat the diseases occurring in skin caused by UV radiation. The antioxidant activity using a chemiluminescent method was used to evaluate the functional stability and the permeation/retention in skin of these formulations. In the long-term stability study, the formulations were stored at 25+/-2 degrees C/AH and at 40+/-2 degrees C/70% RH for 360 days. It was found in this study, that the formulations prepared with Polawax showed functional and physical stability in the period of study. In addition, this formulation presented good results in the percutaneous study, allowing the antioxidant compounds present in the propolis extract to reach lower layers in pig ear skin and in the whole hairless mice skin (retention=0.12 and 0.13 microL of propolis/g of skin, respectively). In the in vivo study, it was also suggested that this formulation may be effective in protecting skin from UVB photodamage, nevertheless other assays need to be done in order to have a complete understanding of the protective effect of formulations added with propolis extract.

Casein, hydrolyzed casein, and amino acids that simulate casein produce the same extent of mucosal adaptation to massive bowel resection in adult rats.

We determined the effect of the extent of protein polymerization on the intestinal hyperplastic adaptation of adult male Wistar rats after 80% resection of the jejunal-ileal segment. Rats received one of four chemically defined solid diets prepared by using casein, two casein hydrolysates of different peptide size distributions, or free amino acids simulating casein and identical in all other components for 12 d, starting 3 d after surgery. Semipaired feeding was used to ensure that the same quantity of food was ingested by each group and as a consequence, nitrogen and energy intakes were reduced to 63% of that obtained with ad libitum feeding of the casein diet to intact rats. No significant differences were demonstrable in food ingestion, weight gain, nitrogen balance, or morphometric data for the remaining jejunal and ileal segments (number of cells/villus, number of cells/crypt, and crypt cell mitosis rate). These data demonstrate that the extent of polymerization of the protein nitrogen source did not affect the hyperplastic adaptative process of the rat. Additional studies in humans are necessary to determine whether intact protein diets can be used first as a nitrogen source in nutritional support of patients with a nonspecific hyperplastic response to surgical resection before the use of expensive hydrolysates and the more expensive amino acid mixtures.

New approaches to the treatment of phenylketonuria.

Phenylketonuria (PKU) is the most common of all aminoacidopathies and is caused by autosomal recessive deficiency of the hepatic phenylalanine hydroxylase system. The diagnosis of PKU should be multifactorial and based on a protein overload test that reveals increased plasma phenylalanine levels during the ingestion of a normal diet, a phenylalanine tolerance test, and in vitro and in vivo activity of the liver enzyme. An individualized diagnosis that characterizes the severity of the disease in each patient provides objective and effective criteria for the dietary treatment of each particular case.

Absence of Trypanosoma cruzi myocardial infection reactivation in Chagas' heart transplant.

The risk of Trypanosoma cruzi myocardial infection reactivation after immunosuppressive therapy has led to precluding heart transplantation as a therapeutic procedure for patients with end-stage Chagas' heart disease. We report a case of an orthotopic heart transplantation in a 43-year-old critically ill chagasic patient with an uneventful postoperative period. He was treated with azathioprine and cyclosporine to control graft rejection and showed no reactivation of the chagasic infection. One year following surgery, the patient is doing well. Nonsteroidal therapy appears not to reactivate T. cruzi infection in transplant chagasic patients.

Influence of formulation on the physicochemical properties of casein microparticles.

Casein microparticles (CAS/MP) have a potential clinical use for targeting drugs. However, the use of organic solvents in their preparation is undesirable. This study was designed to investigate the influence of preparation procedures in aqueous media on the formulation and physicochemical properties of CAS/MP. The first stage involved the influence of the coacervating agents (lactic acid, succinic anhydride, succinic acid and tartaric acid). The second stage studied was the influence of the ionic strength and the third, the influence of adding a thickener, hydroxypropyl cellulose or hydroxypropyl methycellulose (HPC or HPMC), and a plasticizing agent (gelatin). Some physicochemical properties of CAS/MP were evaluated. While the infrared and the thermal analysis showed that all coacervating agents were appropriate for coacervation, the scanning electron microscopy studies showed that the external morphology of the particles was more homogeneous when lactic acid was used. Utilizing lactic acid as the coacervating agent, there was a trend effect of adding NaCl implying that the increasing of the ionic strength resulted in better stability. Finally, the addition of 0.1% HPC plus either 0.25 or 0.5% gelatin resulted in homogeneous formulations. In conclusion, the use of lactic acid plus 0.1% HPC and 0.25% gelatin results in biodegradable and homogeneous CAS/MP, presenting a potentially useful drug delivery system.

Tricuspid endocarditis: a rare infectious complication of cardiac pacemaker in a patient with Chagas' disease--a case report.

Tricuspid endocarditis was diagnosed in a sixty-four-year-old patient with Chagas' disease who had a permanent cardiac pacemaker and whose generator had been replaced five months before an infection in the pocket. The pacing system was replaced by an epicardial one and the patient received antibiotics with good results.

Ultrastructure of peripheral nerves of mice inoculated with rabies virus.

Fourty adult female albino mice were inoculated in the right hind leg with rabies viruses of the street type. The mice were sacrificed with an interval of 24 hours each, starting in the next day after inoculation. From the 10th day ownwards the animals started presenting signs of paralysis, first on the leg where the viruses were inoculated anbnormalities were found in peripheral nerves compatible with axonal degeneration with secondary demyelination but the rabies viruses were not found in the axoplasm, myelin sheet, Schwann cell cytoplasm, endoneural or in the epineural structures.

Prevalence of hypertension in the urban population of Catanduva, in the State of São Paulo, Brazil.

OBJECTIVE: To study the prevalence of systemic hypertension and its control in the population of Catanduva, in the state of São Paulo, Brazil. METHODS: We carried out a randomized cross-sectional population-based study of the urban population of Catanduva with individuals above 18 years of age (688 individuals accounting for 0.9% of the referred population). We interviewed study participants to analyze the major qualitative and quantitative variables that could influence the hypertensive scenario and the risk for systemic hypertension. Blood pressure was measured through the indirect method according to the III Consenso Brasileiro de Hipertensão (III Brazilian Consensus on Hypertension), which established blood pressure levels >/= 140/90 mm Hg as hypertensive. RESULTS: The prevalence of systemic hypertension was higher in individuals with: (1) history of hypertension (p<0.0001); (2) diabetes mellitus (p=0.05); (3) body mass index (B. M. I) >/= 25 kg/m(2) (p<0.001); (4) low educational level (p<0.0001); (5) familial income ranging from 1 to 5 minimum wages (p<0.05); (6) unmarried status (divorced/separated and widow(er)s) (p<0.0001). Of the interviewed individuals, 27.6% (p=0.05) had blood pressure levels under control. CONCLUSION: Our study showed that the prevalence of systemic hypertension was 31.5%, and that 27.6% of the individuals interviewed had blood pressure levels under control at the time of the interview.

[Percutaneous transluminal coronary angioplasty. Analysis of 305 dilatations]. / Angioplastia coronária transluminal percutânea. Análise de 305 dilatações.

PURPOSE: To show the initial experience of this service with the technique of percutaneous transluminal coronary angioplasty. PATIENTS AND METHODS: Between january 1988 and december 1989, 305 coronary angioplasties were performed in 280 patients with age range of 33 to 82 years (being 49% above 60 years old) and 71% male. Among those, 212 (75%) experienced clinical picture of stable angina and 68 (25%) of unstable angina or myocardial infarction. Patients were divided in three groups: group A--those with lesions of 70% or worse in more than one vessel or in the same vessel with or without any other vessel total occlusion (multiple lesions or multiple vessels: 36 patients; group B--those with lesions of 70% or worse in one vessel with at least one occluded vessel: 64 patients; group C--those with lesions of 70% or worse isolated in a single vessel: 180 patients. RESULTS: Of the 280 treated patients, 229 were considered successful (75%). There has been 22 complications (7%) and 9 deaths (3%). The late follow-up (from 1 to 24 months), displayed 28 new procedures based on clinical suspicion of restenosis. Obstruction or occlusion were present in 16 of the later, with 10 being selected to undergo new procedure, one of those twice. The remaining 12 patients received clinical or surgical treatment. CONCLUSION: Aside from the fact that early and midterm results indeed are promising, the procedure is not safe from immediate risks, and limiting late restenosis. Nevertheless, the lesions might be redilated by the same technique, with success rates comparable to the initial one.

[Percutaneous transluminal coronary angioplasty in patients with prior surgical revascularization]. / Angioplastia coronária transluminal percutânea em pacientes com revascularização cirúrgica prévia.

PURPOSE: To show the author's experience with percutaneous transluminal coronary angioplasty (PTCA) in patients with prior coronary bypass surgery. METHODS: Between January 1989 and January 1991, 629 PTCA in 572 patients were performed. Forty-eight had previous revascularization surgery with interval range of 4 days to 10 years. The PTCA sites were divided in three groups: A) native arterial segments, not affected by surgery (26 patients); B) native arterial segments proximal (4 patients) and distal (2 patients) to graft anastomosis; C) in the coronary vein graft (16 patients). RESULTS: The overall primary success was 78%. In groups B and C, 16 procedures were successfully dilated (72%). All failures in group C were due to unstable problems in reaching (4 patients) or crossing (2 patients) the stenosis with the balloon. There was one death in group A and another in group C. CONCLUSION: Angioplasty is an effective alternative for treatment of recurrent ischemia in patients with prior myocardial revascularization surgery and in early results are comparable to the general angioplasty population.

[Biochemical basis of enteral nutrition]. / Bases bioquímicas do suporte nutricional enteral.

Basic biochemical studies have demonstrated the products of protein intraluminal digestion are amino acids and peptides, and the those amino acids as well as small peptides are absorbed by independent mechanisms. The formers are absorbed by specific absorption systems mediated by carriers. The small peptides (di-and tripeptides) are absorbed intact from and may be intracelularlly hydrolised. Peptides with four or more residues are hydrolysed by peptidases located on the brush border of the intestinal villi and then absorbed as amino acids and/or small peptides. Such an absorption through a peptide mechanism is faster than the absorption of free amino acids. These are basic aspects that should direct the use of protein partial enzymatic hydrolisate in human nutrition.

[A resurgence of rheumatic fever. New causes or old attitudes?]. / Ressurgimento da febre reumática. Novas causas ou velhas atitudes?

Bearing in mind that in the last years there has been an increase in rheumatic fever episodes, the authors evaluate the cases recently observed in the department. The data of 3 children born and living in Portugal, the first known outbreak of rheumatic fever observed between June 93 and March 94, were examined. One case presented polyarthritis, another polyarthritis and carditis and the third chorea and carditis. In just one case was the diagnosis of rheumatic fever considered in the beginning, and over-all, failures in the diagnosis and treatment of tonsillitis, and in echocardiographic diagnosis were detected. In view of these examples, the authors conclude that the increasing incidence and morbidity of rheumatic fever is more probably due to forgetfulness of old attitudes than to new causes. Delay in the diagnosis and errors in secondary prophylaxis may influence long term results.

[Individualized monitoring of the therapy with gentamycin using pharmacokinetic methods. Which method to choose?]. / Monitorização individualizada da terapêutica com gentamicina por métodos farmacocinéticos. Que Método escolher?

Gentamicin has an excellent cost/efficacy ratio for gram negative infections treatment. Its use is often limited in clinical practice by its narrow safety margins and a high incidence of toxicity. Gentamicin related nephrotoxicity is a major adverse effect, mostly in patients with other concomitant potential risk factors. As many other Authors we have found in our Internal Medicine Service during 1992 a gentamicin related nephrotoxicity incidence of 22.5%. Various empiric methods and nomograms have shown a significant incidence of error in predicting individualized gentamicin dosage regimens. Pharmacokinetics methods have demonstrated much better results regarding efficacy and toxicity. The aim of this prospective study carried out during 1993-1994 was to individualize by pharmacokinetics methods dosage regimens of gentamicin in patients with one or more concomitant risk factors of nephrotoxicity. The purpose of pharmacokinetics dosage regimens has been to achieve trough serum concentrations of gentamicin in therapeutics range-0.5 to 2 micrograms/ml-on the first 24 to 48 hours of treatment, and the maintenance in this range during all the treatment, avoiding both toxic and under therapeutic levels. The incidence of gentamicin related nephrotoxicity has been evaluated in this population. Twenty patients were studied: 18 males and 2 females aged 59.6 years (19 to 85). All had one or more potential risk factors for nephrotoxicity-65 years or more: 13, previous renal failure: 6, other nephrotoxic drugs: 10, diuretics: 4, dehydration: 5, congestive heart failure: 5, diabetes: 3, hypertension: 3. For the first 10 patients gentamicin dosage regimens have been determined by Sawchuk-Zaske pharmacokinetics method and for the subsequent 10 patients by Bayesian method. The two subpopulations had no significant differences regarding mean age, sex and potential risk factors for nephrotoxicity. Results of Sawchuk-Zaske method: 53 trough gentamicin serum concentration were obtained; 86.8% were within the therapeutic range, 7.5% were toxic and 5.7% were under therapeutic. Results of Bayesian method: 44 determinations of gentamicin through concentrations were obtained; 86.3% within therapeutic range, 2.4% were toxic and 11.3% were under therapeutic. A great variability in pharmacokinetic patient's profile has been found and explains the great variability of individualized dosage regimens of gentamicin (30 to 320 mg/day). No patients had gentamicin related nephrotoxicity. Both pharmacokinetics methods lead to a efficient and save employment of gentamicin in patients with previous renal failure and other potential risk factors for nephrotoxicity.

Masticatory efficiency in class II and class III dentofacial deformities.

Masticatory efficiency may be impaired in individuals with dentofacial deformities. The objective of the present study was to determine the condition of masticatory efficiency in individuals with dentofacial deformities. 30 patients with class II (DG-II) and 35 patients with class III (DG-III) dentofacial deformity participated in the study, all had an indication for orthognathic surgery. 30 volunteers (CG) with no alterations of facial morphology or dental occlusion and with no signs or symptoms of temporomandibular joint dysfunction also participated. Masticatory efficiency was analysed using a bead system (colorimetric method). Each individual chewed 4 beads, one at a time, over 20s measured with a chronometer. The groups were compared in terms of masticatory efficiency using analysis of variance (ANOVA), with the level of significance set at P<0.05. Masticatory efficiency was significantly greater in CG (P<0.05) than in DG-II and DG-III in all chewing tasks tested, with no significant difference between DG-II and DG-III (P>0.05). It was observed that the presence of class II and class III dentofacial deformity affected masticatory efficiency compared to CG, although there was no difference between DG-II and DG-III.

[Inherited aplastic anemias]. / Aplasias medulares congénitas.

The inherited aplastic anaemias are a heterogeneous group of disorders characterized by bone marrow failure, frequent association with one or more somatic anomalies and increased risk of cancer. They are rare disorders, usually diagnosed at paediatric age, and have significant premature mortality. The authors report 11 cases of inherited aplastic anaemias, 8 of Fanconi's anaemia and 3 of Dyskeratosis congenita. These cases were diagnosed in the last 14 years in the Dona Estefânia Hospital.