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1.
Cavernous haemangiomas are the most common orbital masses and the second most common cause of unilateral proptosis after thyroid ophthalmopathy. We retrospectively analysed 19 patients with retrobulbar cavernous haemangiomas, 9 of whom had lateral orbitotomy to remove retrobulbar cavernous haemangiomas located superior (n=4), inferior (n=2) or lateral (n=3) to the optic nerve. Seven patients had lateral orbitotomy together with an anterior medial approach to gain access to retrobulbar cavernous haemangiomas located medially to the optic nerve in the posterior half of the orbit. An anterior approach was used in 3 patient with an anteriorly located cavernous haemangioma. We describe here the planning of surgical treatment based on the site of the lesion.  相似文献   
2.
AIM: To compare using scanning electron microscopy (SEM) root canal walls following instrumentation in vitro with two different rotary NiTi instruments. The hypothesis was that no difference should be observable between the experimental groups in terms of debris on canal walls and surface morphology. METHODOLOGY: Twenty-four single-rooted human teeth were selected. Two types of NiTi instruments were used, Mtwo (Sweden & Martina, Padova, Italy) and ProTaper (Dentsply Maillefer, Ballaigues, Switzerland). Irrigation for both groups was performed after each instrument change with 5% NaOCl, 3% H2O2 and 17% EDTA solutions. Three different areas (coronal, middle and apical thirds) of the root canal were evaluated using SEM. The canal wall of each sample was assessed and compared using a predefined scale of four parameters, namely, smear layer, pulpal debris, inorganic dentine debris, surface profile. Data were analysed statistically using the Kruskal-Wallis test (anova). RESULTS: A statistically significant difference (P < 0.01) was found between the apical third and the middle and coronal thirds for both groups. No difference was observable between instrumentation groups. In the apical third canal walls were often contaminated by inorganic debris and by smear layer. In the apical third, the surface profile was affected by uninstrumented regions, comprising dentine depressions and grooves in which predentine was still visible. CONCLUSION: Both instruments produced a clean and debris-free dentine surfaces in the coronal and middle thirds, but were unable to produce a dentine surfaces free from smear layer and debris in the apical third. The presence of deep grooves and depression on dentine walls in the apical third may well explain the presence of less-instrumented areas.  相似文献   
3.

Objective

Degradation of hybrid layers (HLs) within resin-infiltrated dentine results from multiple degradation factors, including collagenolytic activity of specific matrix metalloproteinases (MMPs). Inhibition of host-derived MMPs may, therefore, slow the degradation of HL. The null hypothesis tested is that the presence of MMP-2 is similar regardless of chlorhexidine (CHX) pre-treatment or the use of an adhesive.

Methods

Powdered dentine prepared from extracted human teeth was divided into 4 groups: (G1) mineralised powder (control group); (G2) dentine powder treated with 1% phosphoric acid for 1 min; (G3) 1% phosphoric acid-etched dentine treated with Adper Scotchbond 1 XT (SB1XT; 3M ESPE); (G4) 1% phosphoric acid-etched dentine treated with 0.2% CHX followed by SB1XT. The concentration of detectable pro-MMP-2 and MMP-2 was assayed using a colorimetric assay system (QuantiSir). In addition, the presence of MMP-2 in the HL was assessed in 1 year-aged adhesive-dentine interfaces using an immunohistochemical approach under FEI-SEM/TEM.

Results

In dentine powder treated with 1% phosphoric acid (G2), MMP-2 level decreased compared to controls (G1); the application of SB1XT (G3) resulted in an increase of MMP-2, whilst 0.2% CHX before SB1XT application (G4), reduced MMP-2. The FEI-SEM/TEM analysis revealed MMP-2 distribution within the HL of aged interfaces showing increase MMP-2 patterns in the control group and minor labelling in the CHX-pretreated specimens.

Conclusion

The results of this study support the use of non-toxic MMPs inhibitors, such as CHX, as an appropriate additional step in bonding procedures in order to increase the longevity of the adhesive restorations.  相似文献   
4.
This study was undertaken to clarify the mechanisms by which C-fiber degeneration at neonatal stages exacerbates the inflammatory responses of rat airways. Rats were treated with capsaicin at neonatal stages and immunized with ovalbumin (OVA) at adult ages. Challenge of capsaicin-pretreated rats with OVA promoted a higher influx of neutrophils in bronchoalveolar lavage (BAL) fluid compared with the vehicle group. No significant differences were found for the other cell types. The increased adhesion of N-formyl-methionyl-leucyl-phenylalanine (fMLP; 0.1 microM)- and phorbol myristate acetate (PMA; 1 microM)-treated neutrophils to fibronectin-coated wells did not differ among vehicle- and capsaicin-pretreated rats. Additionally, fMLP (10 microM), platelet-activating factor (0.1 microM), and substance P (50 microM) induced a significant neutrophil chemotaxis, but no differences were found among vehicle and capsaicin groups. Increased levels of tumor necrosis factor (TNF)-alpha, interleukin (IL)-6, IL-10, and leukotriene B4 in BAL fluid as well as higher expression of cytokine-induced neutrophil chemoattractant (CINC)-3 in lung homogenates were detected in the capsaicin group compared with vehicle group. In the capsaicin group, chronic treatment with compound 48/80 restored the TNF-alpha levels to control values and prevented the neutrophil influx in BAL fluid. The enhanced production of TNF-alpha, superoxide anion, and nitrite by isolated alveolar macrophages in response to lipopolysaccharide (3 microg/ml), PMA (10 nM), and/or zymosan (100 particles/cell) did not differ between vehicle- and capsaicin-pretreated rats. In conclusion, chronic neuropeptide depletion promoted by neonatal capsaicin treatment up-regulates airways mast cells, which upon activation by antigen at adult ages, release large amounts of cytokines such as TNF-alpha and CINC-3 that accounts for the massive airways neutrophil infiltration.  相似文献   
5.
6.
Objectives: The objective of this research was to evaluate the efficacy of a new antifungal imidazole, dapaconazole tosylate, in the treatment of Pityriasis versicolor (PV).

Design and methods: Sixty patients with clinical and mycological diagnosis of PV were randomly assigned to receive either 1 g dapaconazole tosylate 2% cream or 1 g ketoconazole 2% cream. Treatments were applied once a day for 28 days. A dermatologist evaluated efficacy and safety daily, and weekly laboratorial tests were performed. The primary end point was a clinical and mycological cure of lesions after 28 days of treatment. The secondary end point was the time to clinical healing assessed by Kaplan–Meier analysis and Log-rank testing.

Results: Fifty-three patients adhered to protocol rules. Clinical and mycological cure was achieved in 84.6% (22/26) and 92.6% (25/27) of patients treated with ketoconazole and dapaconazole, respectively (difference [effect size] = 8.0%, Standard error of difference: 8.69%, 95% CI: –6.3 to 22.3%). Median time to healing was 23.5 and 21 days for ketoconazole and dapaconazole, respectively (p = 0.126). Adverse events occurred only in ketoconazole-treated patients (13%; 4/30).

Conclusion: Dapaconazole tosylate is non-inferior to ketoconazole when used at a dose of 20 mg/day for 28 consecutive days for the treatment of PV. Dapaconazole also demonstrated a good safety profile.  相似文献   

7.
Glaucoma, the leading cause of visual impairment and irreversible blindness worldwide, is a multifactorial, progressive optic neuropathy characterized by loss of retinal ganglion cells, alterations of the optic nerve head, and specific visual field defects. Clinical evidence shows that intraocular pressure is the major risk factor of the treatable disease. However, in some patients, glaucoma develops and continues to progress despite normal intraocular pressure values, suggesting that other risk factors are involved in the disease. Consequently, neuroprotective treatments, focused on preventing retinal ganglion cells death by acting on different therapeutic strategies but not focused on intraocular pressure reduction, has therefore become of great interest. In this contest, coenzyme Q10, showing evidence in slowing or reversing pathological changes typical of the disease, has been proposed as a potential neuroprotective agent in glaucoma. In this review, we describe the possible mechanisms of action of coenzyme Q10 and the recent evidence in literature regarding the neuroprotective activity of the molecule.  相似文献   
8.
9.
10.
Abstract: Very few data are available on the comparison of infectious complications in peripheral blood stem cell transplantation (PBSCT) and bone marrow transplant (BMT). The objective of this study was to evaluate the severity and frequency of infectious complications in patients randomized to receive PBSCT or BMT. We retrospectively reviewed the charts of all patients included in a randomized clinical trial comparing PBSCT (27 patients) and BMT (29 patients). We analyzed two periods: pre‐engraftment and post‐engraftment. In the pre‐engraftment period, we compared the two groups with respect to the duration of neutropenia, antibiotic use and hospitalization, and documentation of infection. In the post‐engraftment period, we analyzed the occurrence and severity of graft‐versus‐host disease (GVHD), duration of cyclosporine, corticosteroids, antibiotic, antiviral and antifungal prophylaxis, number of episodes of infection, and death rates. Patients receiving PBSCT had shorter duration of neutropenia, but there were no differences in the incidence of infections or duration of antibiotic therapy. Patients receiving PBSCT had a higher incidence of extensive chronic GVHD (65% vs. 39%, P=0.08), longer duration of cyclosporine use (risk ratio [RR] 1.97), corticosteroids (RR 1.66), antibacterial (RR 2.60), antifungal (RR 2.50), anti‐Pneumocystis carinii (RR 2.06) and anti‐cytomegalovirus (RR 1.44) prophylaxis, and more infectious episodes (3.65 vs. 2.32 per 1000 days at risk, RR 1.57). There were no differences in death rates. Multivariate analysis identified the use of steroids as the most significant variable associated with infectious episodes. PBSCT was associated with more infections in the post‐engraftment period.  相似文献   
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