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11.
Background: This study assesses the effects of topical sodium alendronate (SA) as an adjuvant to the mechanical treatment of ligature‐induced periodontitis in rats. Methods: Ninety animals were subjected to the induction of periodontitis via the installation of a ligature around the mandibular left first molar. After 7 days, the ligature was removed, and the animals were distributed into the following groups: 1) NT group (n = 30), no treatment; 2) SRP group (n = 30), scaling and root planing (SRP) and local irrigation with physiologic saline solution; and 3) SRP/SA group (n = 30), SRP and local irrigation with SA (10?5 M). Ten animals from each group were euthanized at 7, 15, and 30 days after treatment. Histologic and histometric analyses were performed in the furcation region. The percentage of bone in the furcation (PBF) was measured. Immunohistochemical analyses for detecting the receptor activator of nuclear factor‐κB ligand (RANKL), osteoprotegerin (OPG), tartrate‐resistant acid phosphatase (TRAP), and activated caspase‐3 were performed at the furcation region. Results: Compared with the other groups, the SRP/SA group showed less local inflammation and better tissue reparation during the entire experiment. There was more PBF in the SRP/SA group than in the other groups at days 7 and 15. Stronger OPG immunolabeling and weaker RANKL immunolabeling were observed in the SRP/SA group at 15 and 30 days. There were fewer TRAP‐positive cells in the SRP/SA group than in the NT group at all of the time points. There was no difference in the number of activated caspase‐3‐positive osteocytes among groups and time points. Conclusion: It can be concluded that topical use of SA as an adjuvant to SRP is effective in the treatment of experimental periodontitis.  相似文献   
12.
The subject of this paper was to conduct an in vitro study of the coronal leakage after root canal filling and post space preparation. One hundred single-rooted human teeth had their crowns removed and the canals prepared and filled by the lateral condensation technique with gutta-percha points and the sealers CRCS and Endofill (a Grossman cement). After post space preparation, the remainder of the filling was protected or not with 1mm of a plug of the following materials: Coltosol, Super Bonder (cyanoacrylate-ester), CRCS and Endofill. After 24 hours in saline, the specimens were immersed in a 2% methylene blue solution in a vacuum environment for 24 hours. The teeth were then sectioned longitudinally, leakage was evaluated linearly and the obtained data were submitted to the Kruskal-Wallis test. The results with the two sealers studied were similar between themselves and worse (p<0.01) than the groups with a protector plug. The statistical analysis ordered the experimental groups from the best to the worst in the following way: a - Endofill-Super Bonder, CRCS-Super Bonder, CRCS-CRCS; b - Endofill-Endofill; c - Endofill-Coltosol, CRCS-Coltosol; d - Endofill, CRCS.  相似文献   
13.
International Journal of Legal Medicine - It is known that Cannabis in Brazil could either originate from Paraguay or be cultivated in Brazil. While consumer markets in the North and Northeast...  相似文献   
14.

Aim of the study

Ilex paraguariensis St. Hilaire (Aquifoliaceae) is a plant widely cultivated in South America that is used to prepare a tea-like beverage with a reputation to improve cognitive function, a response that has been attributed to the constituents of the leaves, especially caffeine. Our previous study indicated that the hydroalcoholic extract of Ilex paraguariensis presents an antiparkinsonian profile in reserpine- and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine hydrochloride (MPTP)-treated rodents.

Materials and methods

In the present study, the effects of the hydroalcoholic extract of Ilex paraguariensis on the short- and long-term learning and memory of rats were assessed with the social recognition, Morris water maze, and step-down inhibitory avoidance tasks.

Results

A preliminary HPLC fingerprint of the plant extract confirmed the presence of caffeine (the major compound), rutin and kaemperol, and revealed the absence of detectable concentrations of caffeic acid, quercetin and ursolic acid. Acute pre-training intraperitoneal (i.p.) or oral administration of the extract of Ilex paraguariensis improved the short-term social memory in a specific manner as well as facilitated the step-down inhibitory avoidance short-term memory evaluated 1.5 h after training. Moreover, a synergistic response was observed following the co-administration of ‘non-effective’ doses of caffeine and Ilex paraguariensis in the social memory. In contrast, pre-training administration of hydroalcoholic extract of Ilex paraguariensis did not alter the step-down inhibitory avoidance long-term memory evaluated 24 h after training, while the highest dose tested (250 mg/kg, i.p.) disrupted the animals’ performance in a cued version of the Morris water maze.

Conclusion

These results partly substantiate the traditional use of mate tea for improvement of cognition indicating that acute administration of hydroalcoholic extract of Ilex paraguariensis differentially modulates short- and long-term learning and memory in rats probably through its antagonist's action on adenosine receptors.  相似文献   
15.

Ethnopharmacological relevance

Copaiba oil has been used in folk medicine since the 19th century. The use of copaiba oils to treat leishmaniasis is cited in several ethnopharmacological studies. Nevertheless, the potential antileishmania of copaiba oils had not been studied.

Aim of the study

Eight different kinds of Brazilian copaiba oils were screened for antileishmanial activity.

Materials and methods

The antiproliferative effect of copaiba oil on promastigote and amastigote axenic were determined. To determine the survival index peritoneal macrophage were infected with promastigotes of Leishmania amazonensis and treated with copaiba oil. The cytotoxic effect of copaiba oil was assessed on macrophage strain J774G8 by assay of sulforhodamine B.

Results

Copaiba oils showed variable levels of activity against promastigote forms with IC50 values in the range between 5 and 22 μg/mL. The most active oil was that from Copaifera reticulata (collected in Pará State, Brazil) with IC50 values of 5, 15, and 20 μg/mL for promastigote, axenic amastigote and intracellular amastigote forms, respectively. Amphotericin B showed IC50 of 0.058 and 0.231 μg/mL against promastigote and amastigote forms, respectively. Cytotoxicity assay showed that this copaiba oil obtained from Copaifera reticulata showed low cytotoxicity against J774G8 macrophages.

Conclusion

Copaiba oils showed significant activity against the parasite Leishmania amazonensis.  相似文献   
16.
17.
This paper describes the synthesis of new cyclic imides obtained by reaction with aminophenazone (CAS 58-15-1, 4-aminoantipyrine) and different anhydrides with further cyclization with acetic acid under reflux. Their structures were confirmed by spectral data (IR and NMR) and elemental analysis. The analgesic activity of the synthesized compounds was investigated initially with the writhing test in mice and the most promising compound, a 3,4-dichloromaleimide derivative (3), was analyzed using other models of nociception. The results indicated that compound 3 exerts potent analgesic activity in mice, being more active than some reference drugs. The analgesia caused by this compound was not reversed by naloxone in the writhing test. In the hotplate test, compound 3 did not increase the latency period of pain induced by thermal stimuli, confirming that it does not interact with opioid systems.  相似文献   
18.
19.

Aim

To evaluate the impact of contrast-enhanced computed tomography colonography (CE-CTC) on laparoscopic surgery planning in patient with stenosing colorectal cancer.

Materials and methods

Sixty-nine patients with endoscopically proven colorectal cancer underwent CE-CTC, after incomplete conventional colonoscopy. Two experienced radiologists evaluated site, length, and TNM staging of colorectal cancers on three-dimensional double contrast enema-like views, 2D axial and multiplanar reconstructions. All the patients underwent colorectal resection and surgery bulletin, pathology of surgical specimens, and radiological follow-up at about 8 months were used as reference standard.

Results

The detection rate of colorectal cancer was 100 % (75/75); CE-CTC allowed for a diagnosis of a synchronous colorectal cancer in five patients (7 %). CE-CTC correctly judged the site of the lesions in all the cases; clinically significant localization errors at conventional colonoscopy were noted in 3 out of 69 patients (4 %). Additional colonic polyps greater than 6 mm in diameter were found in 21 out of 69 patients (30 %); in two patients (3 %) the surgeon performed an enlarged colectomy to include synchronous polyps proximal to colorectal cancer. Sensitivity, specificity, PPV, NPV, and accuracy were for T1–T2 vs. T3–T4: 96 %, 71 %, 92 %, 87 %, and 91 %, respectively; for N: 94 %, 42 %, 64 %, 86 %, and 70 %; for M: 100 %, 100 %, 83 %, 100 %, and 97 %. There were no complications associated with CE-CTC.

Conclusion

Information given by CE-CTC concerning colorectal cancer location and synchronous colonic cancers and polyps changed the laparoscopic surgical strategy in almost 14 % of patients.  相似文献   
20.
The possibility of detecting unknown internal carotid artery stenoses in patients undergoing biphasic multidetector computed tomography (MDCT) for current or previous head and neck cancer was investigated in 52 patients who underwent four-row MDCT (4 mm×1.25 mm collimation, pitch 3, kVp 120, mAs 140; 90–100 ml of non-ionic contrast agent at 2 ml/s, early and late phases). Vessel stenoses were classed as severe (70–99%), moderate (30–69%), or mild (<30%). Internal carotid arteries (ICAs) with vessel stenosis was found in 37 patients (age 67.0±9.8 years, median 69 years) and 67 ICAs. Four patients (age 65.5±9.7 years) had severe stenosis, all of them associated with contralateral moderate stenosis. Seventeen patients (age 70.35±9.78 years) had moderate stenosis, bilateral (n=7), associated with contralateral mild stenosis (n=8), unilateral (n=2). Sixteen patients (age 64.8±9.8 years) had mild stenosis, bilateral (n=10) or unilateral (n=6). Of the four patients with unknown MDCT-detected severe stenosis, three had a change of therapy: one endarterectomy before tumor surgery, one combined vascular and tumor surgery, and one patient with a previously treated hypopharyngeal cancer had carotid stenting. In conclusion, of 52 patients, four (7.7 %) had unknown severe ICA stenoses, three of them with relevant impact on therapy. ICAs should be carefully evaluated for atherosclerotic disease using biphasic MDCT for head and neck cancer.  相似文献   
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