Sublingual immunization with the phosphate-binding-protein (PstS) reduces oral colonization by Streptococcus mutans.

Bacterial ATP-binding cassette (ABC) transporters play a crucial role in the physiology and pathogenicity of different bacterial species. Components of ABC transporters have also been tested as target antigens for the development of vaccines against different bacterial species, such as those belonging to the Streptococcus genus. Streptococcus mutans is the etiological agent of dental caries, and previous studies have demonstrated that deletion of the gene encoding PstS, the substrate-binding component of the phosphate uptake system (Pst), reduced the adherence of the bacteria to abiotic surfaces. In the current study, we generated a recombinant form of the S. mutans PstS protein (rPstS) with preserved structural features, and we evaluated the induction of antibody responses in mice after sublingual mucosal immunization with a formulation containing the recombinant protein and an adjuvant derived from the heat-labile toxin from enterotoxigenic Escherichia coli strains. Mice immunized with rPstS exhibited systemic and secreted antibody responses, measured by the number of immunoglobulin A-secreting cells in draining lymph nodes. Serum antibodies raised in mice immunized with rPstS interfered with the adhesion of bacteria to the oral cavity of naive mice challenged with S. mutans. Similarly, mice actively immunized with rPstS were partially protected from oral colonization after challenge with the S. mutans NG8 strain. Therefore, our results indicate that S. mutans PstS is a potential target antigen capable of inducing specific and protective antibody responses after sublingual administration. Overall, these observations raise interesting perspectives for the development of vaccines to prevent dental caries.

Enhanced bone formation during healing process of tooth sockets filled with demineralized human dentine matrix.

BACKGROUND: Orthodontic procedures are often limited by the presence of bone defects caused by trauma, periodontal diseases or surgeries, thus requiring the development of materials capable to compensate such deficiencies. Since bone morphogenetic proteins (BMPs) are indicative of bone reconstitution, this study aimed to evaluate histological and immunohistochemically the temporal location of BMP-2 and BMP-4 in osteoblasts of rat alveolar wounds filled with demineralized human dentine matrix (DHDM), used as a graft material. METHODS: After extraction of the upper second molars, the left side alveoli were filled with DHDM and the right side served as the control. The animals were euthanized after 3, 5, 10 and 14 days of surgery. After fixation, demineralization and paraffin embedding, representative samples of each group were stained with H&E and immunohistochemically evaluated. RESULTS: The data showed a statistically significant (p < 0.05) increased number of osteoblasts positively immunostained for BMP-2 and BMP-4 on the experimental side (left) at 10 days. Our results also showed that even when not degraded, dentine matrix was incorporated to new bone formation after 14 days of surgery. CONCLUSIONS: The results suggest that DHDM acts as a scaffold for osteoblast differentiation, actively yielding new bone formation, and it may represent an effective bone implant material.

Antinociceptive effect of Lecythis pisonis Camb. (Lecythidaceae) in models of acute pain in mice.

ETHNOPHARMACOLOGICAL RELEVANCE: Lecythis pisonis Camb., also known in Brazil as sapucaia, is used in folk medicine against pruritus, muscle pain and gastric ulcer. AIM OF THE STUDY: To investigate the antinociceptive effect of ethanol extract from Lecythis pisonis leaves (LPEE), fractions (hexane-LPHF, ether-LPEF and ethyl acetate-LPEAF) and mixture of triterpenes [ursolic and oleanolic acids (MT)] in mice. MATERIALS AND METHODS: LPEE and LPEF were evaluated on the acetic acid induced writhings and formalin, capsaicin and glutamate tests. In addition, MT was investigated on the writhings induced by acetic acid, capsaicin and glutamate tests. In the study of some possible mechanisms involved on the antinociceptive effect of LPEF, it was investigated the participation of opioid system, K+ATP channels and L-arginine-nitric oxide pathway. RESULTS: LPEE (12.5 and 25 mg/kg, p.o.), LPEF and MT (6.25, 12.5 and 25 mg/kg, p.o.) reduced the writhings in comparison to saline. LPEE (100 mg/kg, p.o.) and LPEF (50 mg/kg, p.o.) were effective in inhibiting both phases of formalin test. In capsaicin test, LPEE (100 and 200 mg/kg, p.o.), LPEF (12.5-50 mg/kg, p.o) and MT (6.25-25 mg/kg, p.o.) showed a significant antinociceptive effect compared to the control. LPEE (25 and 50 mg/kg, p.o.), LPEF (50 and 100 mg/kg, p.o.) and MT (12.5 and 25 mg/kg, p.o.) reduced the glutamate-evoked nociceptive response. Treatment with naloxone, L-arginine and glibenclamide reversed the effect of LPEF in glutamate test. CONCLUSIONS: These results indicate the antinociceptive effect of Lecythis pisonis leaves and suggest that this effect may be related to opioid pathway, K+ATP channels, and L-arginine-nitric oxide modulation. Furthermore, these data support the ethnomedical use of this plant.

Effects of Lecythis pisonis Camb. (Lecythidaceae) in a mouse model of pruritus.

ETHNOPHARMACOLOGICAL RELEVANCE: Lecythis pisonis Camb. (Lecythidaceae), is popularly known as "Sapucaia". In traditional medicine, leaves are used for the treatment of pruritus. AIM OF THE STUDY: The present study is aimed to investigate the antipruritic effect of the ethanol extract from leaves of Lecythis pisonis (LPEE), fractions (hexane-LPHF, ether-LPEF and ethyl acetate-LPEAF) and mixture of triterpenes [ursolic and oleanolic acids (MT)] in mice and rats. MATERIALS AND METHODS: The LPEE, LPHF, LPEF, LPEAF and MT were evaluated on scratching behavior induced by compound 48/80 in mice. In addition, LPEE, LPEF and MT were investigated on rat peritoneal mast cells degranulation induced by compound 48/80 (ex vivo study). The anti-inflammatory activity of LPEE and LPEF was investigated in rats using carrageenan-induced hind paw edema model. In the evaluation of the spontaneous motor activity, the LPEE was studied for its effect on spontaneous motor activity in an open-field test in mice. RESULTS: The scratching behavior induced by compound 48/80 was significantly inhibited in mice pretreated with LPEE, LPHF, LPEF, LPEAF and MT. The suppressive effect of LPEE, LPEF and MT was only partially antagonized by naloxone. In addition, the compound 48/80-elicited degranulation of rat peritoneal mast cells was also markedly reduced in animals pretreated with LPEE, LPEF and MT. In the anti-inflammatory test, LPEE decreased the paw edema at the third hour after carrageenan (Carr) administration. Moreover, LPEF also was able to inhibit the oedematogenic response evoked by carr at all analysed time points. In the open-field test, LPEE-pretreated mice showed no impairment of spontaneous locomotion. Furthermore, the LPEE demonstrated no overt toxicity up to an oral dose of 2g/kg in an acute toxicity assay. CONCLUSIONS: These results clearly indicate the antipruritic effects of Lecythis pisonis leaves and suggest that this effect may be related to a stabilizing action on mast cell membrane. Furthermore, these data support the traditional use of this plant against cutaneous pruritus.

Influence of age, central corneal thickness, and quality score on dynamic contour tonometry.

AIMS: To compare the IOP measurements obtained with dynamic contour tonometry (DCT) and Goldmann applanation tonometry (GAT), and to analyse the influence of central corneal thickness (CCT) and age on both measurements, and the influence of the quality score on DCT readings. METHODS: A total of 500 healthy subjects with no prior history of glaucoma or ocular hypertension (age: 7-86 years) were consecutively recruited. GAT, DCT, and CCT measurements were obtained from both eyes of each individual, in this order, by three observers. The mean of five CCT measurements was used for analysis. DCT measurements were accepted when quality scores varied between 1 (higher quality) and 3 (lower quality). RESULTS: Mean DCT measurements were 3.2 mmHg higher than GAT readings. CCT values varied between 449 and 653 microm. IOP measured by GAT correlated strongly with CCT (r(2)=0.28, P=<0.001), whereas DCT readings correlated poorly with CCT (r(2)=0.01, P=0.017). Both DCT (r(2)=<0.01, P=0.044) and GAT (r(2)=0.01, P=<0.001) measurements correlated poorly with age. Bland-Altmann analysis revealed disagreement between DCT and GAT readings, with 95% confidence intervals of +/-6.7 mmHg. Quality scores for DCT measurements were 1 (n=369, 36.9%), 2 (n=340, 34.0%), and 3 (n=291, 29.1%). DCT readings with quality score of 3 (18.8+/-3.4 mmHg) were significantly higher than those with quality scores of 1 (16.7+/-2.9 mmHg) and 2 (17.4+/-2.9 mmHg; P=<0.001). CONCLUSIONS: DCT is not influenced by CCT, unlike GAT. Both DCT and GAT measurements are not influenced by age. DCT measurements with lower quality scores are associated with higher readings.

Clinical and macroscopic study of maxillary molars with two palatal roots.

AIM: To report an anatomical variation in maxillary first molars. SUMMARY: A case report is presented of a maxillary first molar requiring root-canal treatment that had two palatal roots with distinct canals and foramena at the apical level. Root-canal treatment was performed using mechanical instrumentation with NiTi files. An anatomical study on two extracted maxillary second molars with the same variation revealed their internal structure. This case demonstrates an uncommon anatomical condition and supplements previous reports of such cases affecting maxillary molars. KEY LEARNING POINTS: Clinicians should be aware of uncommon anatomical variations in maxillary molars. The majority of maxillary first molars have three roots and four canals. Maxillary molars may have two canals in the palatal root.

Efficiency of the 0.04 taper ProFile during the re-treatment of gutta-percha-filled root canals.

AIM: The objective of this study was to determine the effectiveness of 0.04 ProFile instruments during the removal of root fillings. METHODOLOGY: A total of 30 single-rooted mandibular canines were divided into three groups. The canals were accessed and then prepared with a reciprocating automated device and nickel-titanium files. Three different techniques of obturation were used: Thermafil system (group I), thermomechanical compaction (group II) and lateral condensation (group III). Sealer 26 was used in all three groups. Two weeks after obturation, the fillings were removed using 0.04 ProFile instruments following standardized sequence of size 90, 60, 45, 40, 35 and 30 at a speed of 300 rpm in a crown-down manner. The teeth were subsequently split with a chisel, photographs were taken with a colour video camera and the removal of filling material was assessed visually (by colour) by two examiners. The time required to achieve the working length was also recorded. RESULTS: ProFile instruments reached the working length in all cases. However, complete removal of gutta-percha occurred in only three specimens (two of group I, and one of group II). Thermafil plastic carriers were removed successfully in all specimens of group I. CONCLUSIONS: ProFile instruments with 0.04 taper were inadequate in completely removing the filling materials from the root canal system. However, the ideal working length was achieved rapidly.

[Acute urologic symptoms associated with uterine myoma]. / Sintomatología urológica aguda asociada al mioma uterino.

While prevalence of uterine leiomyoma is high, its presentation affecting the urinary tract is uncommon. We contribute the cases of two adult women with symptoms of nephritic colic and urinary retention. Etiology was acute obstruction of the urinary tract due to previously asymptomatic urine myomas. Management in both patients was surgery, using hysterectomy to resolve the urinary obstruction. A brief review of the literature is included.