Biocompatibility and mineralized nodule formation of Neo MTA Plus and an experimental tricalcium silicate cement containing tantalum oxide.

AIM: To evaluate the biocompatibility and mineralized nodule formation of an experimental tricalcium silicate cement with tantalum oxide (TSC/Ta2 O5 ) as radiopacifier, Neo MTA Plus (Avalon Biomed Inc., Bradenton, FL, USA) and MTA (Angelus, Londrina, PR, Brazil) on human osteoblast-like cells (Saos-2). METHODOLOGY: Biocompatibility was evaluated by 3-(4,5-dimethyl-thiazoyl)-2,5-diphenyl-tetrazolium bromide (MTT) and neutral red (NR) assays, after exposure of Saos-2 to cement extracts at 1 : 1, 1 : 2, 1 : 4 and 1 : 8 dilutions for 24 h. Bioactivity was evaluated by alkaline phosphatase (ALP) activity, and calcium deposits were detected with alizarin red staining (ARS). Statistical analysis was performed with analysis of variance and Bonferroni or Tukey post-test (α = 0.05). RESULTS: The MTT assay revealed lower cytotoxicity for NEO and MTA (P < 0.05), and higher for TSC/Ta2 O5 at 1 : 1 and 1 : 2 dilutions when compared to serum-free medium - control (P > 0.05). At 1 : 4 dilution, the TSC/Ta2 O5 cytotoxicity was similar to the control (P > 0.05). At 1 : 8 dilution, cell viability was significantly greater than the control (P < 0.05). Saos-2 cell viability performed using the NR assay at all dilutions revealed no cytotoxic effect of MTA, NEO and TSC/Ta2 O5 . ALP activity at 1 and 3 days was similar to the control (P > 0.05). TSC/Ta2 O5 had significantly greater ALP activity at 7 days when compared with the control (P < 0.05). All materials induced the production of mineralized nodules, and NEO produced significantly more mineralized nodules than MTA and TSC/Ta2 O5 (P < 0.05). CONCLUSIONS: Neo MTA Plus and TSC/Ta2 O5 were biocompatible and induced ALP activity in Saos-2 cells. Both materials induced mineralized nodule formation by Saos-2 with Neo MTA Plus producing significantly more.

The influence of fixed orthodontic appliances on masticatory and swallowing threshold performances.

To test the hypothesis that treatment with orthodontic appliances disturbs masticatory and swallowing performances. Twenty-seven subjects with malocclusions requiring orthodontic treatment were included in this prospective study. The masticatory and swallowing performances were evaluated at five different times: before bracket placement (T0), immediately after archwire placement (T1), 48 h after archwire placement (T2), 30 days after archwire placement (T3) and 3 months after the initial appointment (T4). Masticatory performance was determined by the median particle sizes for the Optocal test food after 15 chewing strokes, and the swallowing thresholds were registered for both the test food and a natural food (peanuts). Pain during mastication was evaluated using a 100-mm visual analogue scale. Masticatory performance was significantly reduced at T2, at which time patients reported the highest pain values. The time spent to the first swallow was increased at T2 for the natural food but not for the test food. The values for pain, masticatory and swallowing performances at T3 and T4 were similar to those at T0. Orthodontic patient masticatory function is only reduced during the period of higher pain experience, which could also disrupt the deglutition of harder foods. However, neither mastication nor deglutition processes were disturbed by orthodontic appliances in long-term treatment.

Assessing the quality of HIV/AIDS services at military health facilities in Zambia.

After rapidly scaling up HIV/AIDS-related health services, the Zambian Defence Force (ZDF) has become concerned with assuring their quality. This evaluation assesses provider performance at eight ZDF facilities based on direct observations of 191 antenatal care (ANC) consultations and 175 follow-up consultations for antiretroviral therapy (ART). In addition, 43 ZDF health providers were interviewed about the work environment and service quality. On-the-job performance varied widely: providers completed as few as 0% and as many as 100% of tasks associated with each performance standard. Overall scores averaged 66% (range: 47-93%) for ANC consultations and 60% (range: 37-100%) for ART consultations. Perceptions of the work environment were generally positive, but 57% of providers lack confidence in their clinical skills and 42% think staffing is insufficient. These findings, which point to the unique opportunities and challenges in the military setting, will be used to guide a quality improvement initiative.

Evaluation of facial asymmetry and masticatory muscle thickness in children with normal occlusion and functional posterior crossbite.

AIM: The aim of this study was to evaluate facial asymmetry and the thickness of the masticatory muscles in young children with normal occlusion and functional posterior crossbite. METHODS: The sample comprised 72 children of both genders (64.71±7.04 months) in the primary and early mixed stage of dentition, divided into four groups: primary-normal occlusion (PriN; N=19), primary-crossbite (PriC; N=19), mixed-normal occlusion (MixN; N=27), and mixed-crossbite (MixC; N=16). The thickness of the masseter and anterior portion of the temporalis muscle at rest and during maximal clenching were assessed by ultrasonography. Facial morphology and asymmetry were evaluated by standardized front-view photographs, in which the following measurements were recorded: anterior face height (AFH), bizygomatic facial width (BFW), angle of the eye (AE) and angle of the mouth (AM) (interpupillary and commissure planes in relation to mid-sagittal plane, respectively). RESULTS: The results showed that muscle thickness did not differ significantly between the sides of the dental arches in all groups (paired t-test). Only the groups with normal occlusion presented significant positive correlation between AE and AM (Pearson's correlation test). In PriN, only body weight was significantly related to masseter thickness; in MixN, facial morphology contributed significantly to masseter thickness at rest and maximal clenching, while the covariates weight, height and age did not relate to muscle thickness (stepwise backward multiple regression). CONCLUSION: In the studied sample, children with crossbite presented greater facial asymmetry than those with normal occlusion, and a greater masseter thickness was related to larger faces in the mixed dentition.

Electromyographic activity and thickness of masticatory muscles in children with unilateral posterior crossbite.

The aim of this study was to assess the electromyographic (EMG) activity and thickness of the masseter and anterior temporalis muscles in children with unilateral posterior crossbite (PCB). Thirty-six children (22 boys, 14 girls, and mean age of 8.8 +/- 1.1 years) were divided into the following groups: The case group with 20 PCB patients (10 on the left side, 10 on the right side); the control group with 16 normal occlusion (NOccl) subjects. EMG activity was recorded with bipolar surface electrodes at rest and during maximal clenching. The muscle thickness was measured with real-time ultrasound. Data were compared between groups and between sides. The correlation between EMG activity and muscle thickness was also evaluated. The data were analyzed using the Shapiro-Wilks test, Pearson's correlation and Spearman as appropriate, paired and unpaired t- test, and Mann-Whitney test. The results revealed that the masseter of the crossbite side was more active than that of the non-crossbite side in PCB group during maximal clenching. The comparisons of EMG activity between PCB and NOccl groups revealed some variability in the results, depending on the crossbite side. The ultrasonographic evaluation did not show statistically significant differences between groups, nor between sides in the PCB and NOccl groups. Significant correlation between EMG activity and thickness was observed only in the left masseter in the NOccl group. In conclusion, these findings showed that asymmetric muscle activity of the masticatory muscles was not related to the thickness of these muscles in children with PCB.

Assessment of copper and lipid profile in obese children and adolescents.

The aim of this study was to assess erythrocyte and plasma copper concentrations and correlate them with the lipid profile of overweight and obese children and adolescents. The study was performed with 15 overweight and 30 obese children and adolescents, and the results were compared to the control group (21), aged 6-16 yr. Anthropometric assessment was carried out using body mass index (BMI). Total cholesterol, low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, and triglyceride serum levels were investigated. Erythrocyte and plasma copper levels were determined by atomic absorption spectrophotometry. Greater alterations in the lipid profile were observed in HDL-cholesterol, LDL-cholesterol, and triglyceride levels, with distinctions according to gender. The plasma copper concentrations in the overweight and obese male groups were significantly higher than those in the control group (p = 0.0006). Negative correlations between plasma copper and total cholesterol (r = -0.54) and LDL cholesterol (r = -0.59) were observed in the obese male group. There was no statistical difference in copper erythrocyte concentrations. The obesity associated to disorders in lipid metabolism predisposes to changes in copper plasma concentrations, but there was no alteration in intracellular reserves, which suggests an important homeostatic control to compensate for plasma oscillations and metabolic alterations of the disease.

Relação entre proteína dietética e calciúria em crianças e adolescentes com nefrolitíase / Relation between diet protein and calciuria in children and adolescents with nephrolitiasis

PURPOSE: The objective was to evaluate the quality of diet and the relationship between protein diet and calciuria in children and adolescents with nephrolithiasis. METHODS: Forty-nine children and adolescents (28 male and 21 female; 10.1 +/- 3.16 years old) with nephrolithiasis were included in study. Diet evaluation was performed over a 3 day period in order to determine nutrient consumption. The analysis of diets were carried out by DietWin Clínico 3.0 software. One 24-hour urine sample was collected for the measurement of calcium. Nutritional status was also assessed by Body Mass Index (BMI). RESULTS: The diet of patients containe insufficient energy and calcium. High levels of protein (69.64 +/- 16.42 gm), mainly animal source (65.81 +/- 11.45%) and low levels of calcium (500.95 +/- 284.64 mg) was observed (95%). Analysis of 24 hour urine samples revealed that 25.0% of the patients presented hypercalciuria. A positive correlation (r = 0.26680) between animal protein intake and calciuria was found, in opposite of vegetable protein and calciuria correlation (r = -0.2675). CONCLUSIONS: Animal protein of the diet has a significant effect in urinary excretion of calcium in patients with nephrolithiasis.

Use of DNA-based diagnostic methods for human leishmaniasis in Minas Gerais, Brazil.

DNA hybridisation was used to type 26 samples from lesions of human patients from the Rio Doce Valley (Minas Gerais, Brazil) clinically diagnosed as having cutaneous leishmaniasis, using kinetoplast DNA (kDNA) cloned mini-circle probes specific for the Leishmania mexicana and Leishmania braziliensis complexes. All samples were found to belong to the L. braziliensis complex. When biopsies were pressed directly onto touch blot membranes 38.5% of the samples were positive. The positivity and specificity obtained were both 100% when cultured blotted parasites were used. The results were confirmed by polymerase chain reaction (PCR) analysis using primers specific for the L. mexicana and L. braziliensis complexes.

Leishmania (Leishmania) amazonensis: purification and enzymatic characterization of a soluble serine oligopeptidase from promastigotes.

A soluble proteinase was purified 90-fold from extracts of promastigotes of Leishmania (Leishmania) amazonensis using a combination of ion-exchange chromatography in Q-Sepharose Fast Flow, gel filtration chromatography in Sephacryl HR S-200, and chromatofocusing. The enzyme appeared as a single band with an apparent molecular weight of 101 kDa by silver staining following SDS-PAGE, under both reducing and nonreducing conditions. The proteinase has a pH optimum between 8.0 and 8.5 and an isoelectric point between 5.12 and 5.23, belongs to the serine proteinase class, and is inhibited by Mg2+, Ca2+, and K+. The primary specificity determined using synthetic substrates is for basic amino acids. The kinetic parameters for the Bz-L-Arg-Nam substrate are Km = 26 microM, kcat = 32 min(-1), and Ksi = 1270 microM (the proteinase showed inhibition by excess substrate). The enzyme does not hydrolyze casein, albumin, and gelatin or large peptides like the oxidized insulin B chain, but hydrolyzes small peptides like bradykinin and fragment 4-10 of the adrenocorticotropic hormone, at the carboxyl side of basic residues and aromatic residues preceding basic residues. The enzyme appears, thus, to be restricted in its action, cleaving only small peptide substrates, which characterizes the proteinase as an oligopeptidase. This is the first report of purification of a serine peptidase from Leishmania species and it increases the short list of known oligopeptidases.

Purification of bovine pancreatic glucagon as a by-product of insulin production

A process for purifying bovine pancreatic glucagon as a by-product of insulin production is described. The glucagon-containing supernatant from the alkaline crystallization of insulin was precipitated using ammonium sulfate and isoelectric precipitation. The isoelectric precipitate containing glucagon was then purified by ion-exchange chromatography on Q-Sepharose FF, gel filtration on Sephadex G-25 and ion-exchange chromatography on S-Sepharose FF. A pilot scale test was performed with a recovery of 87.6 percent and a purification factor of 8.78 for the first chromatographic step, a recovery of 75.1 percent and a purification factor of 3.90 for the second, and a recovery of 76.2 percent and a purification factor of 2.36 for the last one. The overall yield was 50 percent, a purification factor of 80.8 was obtained and the fraction containing active glucagon (suitable for pharmaceutical preparations) was 84 percent pure as analyzed by HPLC.

Purification of bovine pancreatic glucagon as a by-product of insulin production.

A process for purifying bovine pancreatic glucagon as a by-product of insulin production is described. The glucagon-containing supernatant from the alkaline crystallization of insulin was precipitated using ammonium sulfate and isoelectric precipitation. The isoelectric precipitate containing glucagon was then purified by ion-exchange chromatography on Q-Sepharose FF, gel filtration on Sephadex G-25 and ion-exchange chromatography on S-Sepharose FF. A pilot scale test was performed with a recovery of 87.6% and a purification factor of 8.78 for the first chromatographic step, a recovery of 75.1% and a purification factor of 3.90 for the second, and a recovery of 76.2% and a purification factor of 2.36 for the last one. The overall yield was 50%, a purification factor of 80.8 was obtained and the fraction containing active glucagon (suitable for pharmaceutical preparations) was 84% pure as analyzed by HPLC.

[Obstetric factors associated with low birth weight]. / Fatores obstétricos associados ao baixo peso ao nascer.

An analysis was made of 18,804 of 19,446 consecutive births of the number analysed 15.93% presented low birth-rate. Significant statistical association was found in relation to maternal age, pre-natal care, previous pregnancies, smoking and gestational age at birth. Measures with a view to the attenuation of the problem are proposed, among them being: educational programs for teenagers on human reproduction, programs designed to create awareness of the harm done by smoking, amplification of antenatal assistance, medical programs for the limitation of premature labor, all of these and others, in association with programs of socio-economic support.