Experimental periodontal disease treatment by subgingival irrigation with tetracycline hydrochloride in rats

Objective: The aim of this study was to compare subgingival irrigation with tetracycline hydrochloride (TTC-HCL) as adjunctive treatment to scaling and root planning (SRP) on induced periodontitis in rats. Material and Methods: In 60 rats, periodontal disease was ligature-induced at the mandibular left first molar. After 7 days, the ligature was removed and all animals were submitted to SRP, and divided into 2 groups according to the following treatment: C (n=30) - subgingival irrigation with 1 mL of saline; T (n=30) - subgingival irrigation with 1 mL of TTC-HCL (50 mg/mL). Ten animals in each group were euthanized at 7, 15 and 30 days posttreatment. The histometric values were statistically analyzed (p<0.05). Results: In the histometric analysis, at 7, 15 and 30 days, Group T (0.72+/-0.05 mm(2), 0.57+/-0.14 mm(2), 0.62+/-0.07 mm(2)), showed less bone loss (p<0.05) than Group C (1.35+/-0.25 mm(2); 1.40+/-0.31 mm(2); 1.29+/-0.27 mm(2)), respectively. Conclusions: Subgingival irrigation with TTC-HCL was an effective adjunctive treatment for periodontal disease induced in rats.

Comparative analysis of root surface smear layer removal by different etching modalities or erbium:yttrium-aluminum-garnet laser irradiation. A scanning electron microscopy study

The purpose of this study was to evaluate the effect of erbium:yttrium-aluminum-garnet (Er:YAG) laser (2.94 mu m) irradiation on the removal of root surface smear layer of extracted human teeth and to compare its efficacy with that of citric acid, ethylenediamine tetra-acetic acid (EDTA), or a gel containing a mixture of tetracycline hydrochloride (HCl) and citric acid, using scanning electron microscopy (SEM). Thirty human dentin specimens were randomly divided into six groups: G1 (control group), irrigated with 10 ml of physiologic saline solution; G2, conditioned with 24% citric acid gel; G3, conditioned with 24% EDTA gel; G4, conditioned with a 50% citric acid and tetracycline gel; G5, irradiated with Er:YAG laser (47 mJ/10 Hz/5.8 J/cm(2)/pulse); G6, irradiated with Er:YAG laser (83 mJ/10 Hz/10.3 J/cm(2)/pulse). Electron micrographs were obtained and analyzed according to a rating system. Statistical analysis was conducted with Kruskal-Wallis and Mann-Whitney tests (P < 0.05). G1 was statistically different from all the other groups; no statistically significant differences were observed between the Er:YAG laser groups and those undergoing the other treatment modalities. When the two Er:YAG laser groups were compared, the fluency of G6 was statistically more effective in smear layer removal than the one used in G5 (Mann-Whitney test, P < 0.01). Root surfaces irradiated by Er:YAG laser had more irregular contours than those treated by chemical agents. It can be concluded that all treatment modalities were effective in smear layer removal. The results of our study suggest that the Er:YAG laser can be safely used to condition diseased root surfaces effectively. Furthermore, the effect of Er:YAG laser irradiation on root surfaces should be evaluated in vivo so that its potential to enhance the healing of periodontal tissues can be assessed.

In Vitro Evaluation of Surface Roughness and Microhardness of Restorative Materials Submitted to Erosive Challenges

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

Protection of short-time enamel erosion by different tetrafluoride compounds

objective: This in vitro study aimed to analyse the protective effect of differently concentrated titanium (TiF4), zirconium (ZrF4) and hafnium (HfF4) tetrafluoride on enamel erosion. Methods: Polished enamel surfaces of 36 bovine crowns were covered with tape leaving 4 enamel windows each 3 mm in diameter exposed. The crowns were randomly assigned to six groups (each n = 6) and pretreated with 4% TiF4, 10% TiF4, 4% ZrF4, 10% ZrF4, 4% HfF4 or 10% HfF4 for 4 min (first window), 10 min (second window) or 15 min (third window). The fourth window of each crown was not pretreated and served as control. Erosion was performed stepwise with 1% HCl (pH 2) in five consecutive intervals of each 15 s (total 75 s). Enamel dissolution was quantified by colorimetric determination of phosphate release into the acid. For each tooth, cumulative phosphate loss of enamel pretreated with one of the tetrafluoride compounds was calculated as percentage of the respective control and statistically analysed using two-way ANOVA.Results: Enamel erosion was significantly reduced by TiF4, ZrF4 and HfF4 application. Cumulative phosphate loss (mean % of control, 75 s erosion) after 4-15 min application was significantly lower for 4% ZrF4 (7-11%), 10% ZrF4 (2-6%), 4% HfF4 (11-9%) and 10% HfF4 (12-16%) compared to 4% TiF4 (42-27%) and 10% TiF4 (54-33%). Only for 4% and 10% TiF4, phosphate loss decreased with increasing duration of application, but also increased with increasing acid intervals.Conclusion: TiF4, ZrF4 and HfF4 might protect enamel against short-time erosion, but protection was more enhanced by ZrF4 and HfF4 compared to TiF4 application overtime. (C) 2008 Elsevier Ltd. All rights reserved.

Growth performance of Nile tilapia, Oreochromis niloticus, fed diets containing levels of pyridoxine and haematological response under heat stress

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

Qualea parviflora Mart.: An integrative study to validate the gastroprotective, antidiarrheal, antihemorragic and mutagenic action

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

Davilla elliptica and Davilla nitida: Gastroprotective, anti-inflammatory immunomodulatory and anti-Helicobacter pylori action

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

Gastroprotective effect of Cissus sicyoides (Vitaceae): Involvement of microcirculation, endogenous sulfhydryls and nitric oxide

Aim of the study: Cissus sicyoides L. is a medicinal plant popularly known in Brazil against various diseases and the research interest in this plant is justifiable because of its potential medicinal value in stomachache and gastric ulcer.Materials and methods: The methanolic extract obtained from the leaves of Cissus sicyoides (Cc) was evaluated for the ability to protect the gastric mucosa against injuries caused by necrotizing agents (0.3 M HCl/60% EtOH, absolute ethanol, piroxicam and pylorus ligature) in rodents. We also evaluated microcirculation, antioxidant action and participation of NO (nitric oxide) and sulfhydryls (SH) groups in the Cc gastroprotective action.Results: Administration of Cc significantly reduced gastric lesions induced by different ulcerogenic agents in rodents. This extract administered by oral route significantly increased gastric volume without exerting antisecretory effect. The Cc effect involved an increase of the defense mechanism of the gastrointestinal mucosa such as NO and SH groups that prevent and attenuate the ulcer process. The Cc also has antioxidant property against oxidative stress but does not modify microcirculation response in gastric mucosa.Conclusions: These results confirmed the traditional use of Cissus sicyoides for the treatment of gastric ulcer. (C) 2008 Elsevier B.V. All rights reserved.

Determination of copper, iron, nickel and zinc in gasoline by FAAS after sorption and preconcentration on silica modified with 2-aminotiazole groups

Silica gel chemically modified with 2-aminotiazole groups (SiAT), was used for preconcentration of cupper, zinc, nickel and iron from gasoline, normally used as a engine fuel. Surface characteristics and surface area of the silica gel were obtained before and after chemical modification using FT-IR, Kjeldhal and surface area analysis (B.E.T.). The retention and recovery of the analyte elements were studied by applying batch and column techniques. The experimental parameters, such as shaking time in batch technique, flow rate and concentration of the eluent (HCl-0.25-2.00 mol 1(-1)) and the amount of silica, on retention and elution, have been investigated. Detection limits of the method for cupper, iron, nickel and zinc are 0.8, 3, 2 and 0.1 mug 1(-1), respectively. The sorption-desorption of the studied metal ions made possible the development of a preconcentration method for metal ions at trace level in gasoline using flame AAS for their quantification. (C) 2004 Published by Elsevier Ltd.

Byrsonima intermedia A. Juss.: Gastric and duodenal anti-ulcer, antimicrobial and antidiarrheal effects in experimental rodent models

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

Byrsonima fagifolia: An integrative study to validate the gastroprotective, healing, antidiarrheal, antimicrobial and mutagenic action

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

Brazilian Medicinal Plant Acts on Prostaglandin Level and Helicobacter pylori

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

Determination of Cd(II), Cu(II) and Ni(II) in aqueous samples by ICP-OES after on-line preconcentration in column packed with silica modified with 2-aminothiazole

This work describes the synthesis and characterization of 2-aminothiazole modified silica gel (SiAT) and the studies of adsorption and pre-concentration (in batch and using a flow-injection system coupled with optical emission spectrometer) of Cd(II), Cu(II) and Ni(II) in aqueous medium. The adsorption capacity for each metal ions in mmolg(-1) was: Cu(II) = 1.18, Ni(II) = 1.15 and Cd(II) = 1.10. The results obtained in the flow experiments showed about 100% of recovering of the metal ions adsorbed in a mini-column packed with 100 mg of SiAT, using 100 mu L of 2.0 mol L-1 HCl solution as eluent. The quantitative sorption-desorption of the metal ions made possible the application of a flow-injection system in the pre-concentration and quantification by ICP-OES of metal ions at trace level in natural water samples.

The anti-ulcerogenic effects of Curatella americana L.

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Antiulcerogenic activity of Alchornea castaneaefolia: Effects on sornatostatin, gastrin and prostaglandin

The hydroethanolic extract of the leaves (HEL) and bark (HEB) obtained from Alchornea castaneaefolia (Euphorbiaceae) were investigated for their ability to prevent ulceration of the gastric mucosa in animal models. HEL (500 and 1000 mg/kg) and HEB (1000 mg/kg) significantly reduced the gastric injuries induced by the combination of HCl/ethanol and lowered the severity of gastric damage formation induced by indomethacin/bethanechol in mice. Further investigation showed that HEL also inhibited formation of ulcers in mice submitted to stress and pylorus ligature, but HEL did not modify gastric juice parameters in Shay mice. HEL was also effective in promoting the healing process in chronic gastric ulcer induced by acetic acid in rats. An enriched flavonoidic fraction (EFF at dose of 100 mg/kg) obtained from HEL reduced gastric lesions induced by HCl/ethanol and indomethacin/bethanechol in mice. Although EFF did not modify the amount of free mucus production by gastric mucosa, it was able to increase prostaglandin production. When administered to rats submitted to ethanol-induced gastric lesions, EFF increased the somatostatin serum levels, while the gastrin serum levels were proportionally decreased. Phytochemical investigation on HEL and EFF led to the isolation of flavonoids glycosides as the main compounds, thus suggesting that these substances may be involved in the observed antiulcer activity. (c) 2005 Elsevier B.V.. All rights reserved.