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31.
Free radical production and oxidative stress are known to increase in liver during aging, and may contribute to oxidative damage. The objective of this study was to observe the changes in activities of antioxidant enzymes (superoxide dismutase, glutathione-S-transferase, catalase), lipid peroxidation levels and serum nitric oxide occurring in livers of rats of 2, 10 and 20 months old, and to see whether these changes are restored to those of the two month old control levels rats after administration of safranal. The aged rats (10 and 20 months) were given intraperitoneal injections of safranal (0.5 mg/kg day) daily for one month. The results obtained in the present work revealed that normal aging was associated with a significant decrease in the activities of antioxidant enzymes, and an increase in lipid peroxidation in livers and nitric oxide content in serum of aging rats. The results of the present study demonstrate that safranal could be a candidate to suppress the development of age-induced damage by protecting against oxidative stress and increasing antioxidant defenses. A likely mode of action of safranal can be its activity as a hormetin by inducing mild oxidative damage which leads to the activation of antioxidative enzymes.  相似文献   
32.
PURPOSE: Identification of a novel rhodopsin mutation in a family with retinitis pigmentosa and comparison of the clinical phenotype to a known mutation at the same amino acid position. METHODS: Screening for mutations in rhodopsin was performed in 78 patients with retinitis pigmentosa. All exons and flanking intronic regions were amplified by PCR, sequenced, and compared to the reference sequence derived from the National Center for Biotechnology Information (NCBI, Bethesda, MD) database. Patients were characterized clinically according to the results of best corrected visual acuity testing (BCVA), slit lamp examination (SLE), funduscopy, Goldmann perimetry (GP), dark adaptometry (DA), and electroretinography (ERG). Structural analyses of the rhodopsin protein were performed with the Swiss-Pdb Viewer program available on-line (http://www.expasy.org.spdvbv/ provided in the public domain by Swiss Institute of Bioinformatics, Geneva, Switzerland). RESULTS: A novel rhodopsin mutation (Gly90Val) was identified in a Swiss family of three generations. The pedigree indicated autosomal dominant inheritance. No additional mutation was found in this family in other autosomal dominant genes. The BCVA of affected family members ranged from 20/25 to 20/20. Fundus examination showed fine pigment mottling in patients of the third generation and well-defined bone spicules in patients of the second generation. GP showed concentric constriction. DA demonstrated monophasic cone adaptation only. ERG revealed severely reduced rod and cone signals. The clinical picture is compatible with retinitis pigmentosa. A previously reported amino acid substitution at the same position in rhodopsin leads to a phenotype resembling night blindness in mutation carriers, whereas patients reported in the current study showed the classic retinitis pigmentosa phenotype. The effect of different amino acid substitutions on the three-dimensional structure of rhodopsin was analyzed by homology modeling. Distinct distortions of position 90 (shifts in amino acids 112 and 113) and additional hydrogen bonds were found. CONCLUSIONS: Different amino acid substitutions at position 90 of rhodopsin can lead to night blindness or retinitis pigmentosa. The data suggest that the property of the substituted amino acid distinguishes between the phenotypes.  相似文献   
33.
Reversed saphenous fasciocutaneous island flap in marjolin's ulcers   总被引:2,自引:0,他引:2  
BACKGROUND: The reconstruction of the heel represents a challenge due to the limited local soft tissue availability and also due to the special structural and functional characteristics of this region. A great number of possibilities have been described; we represent a new flap for heel reconstruction which is a modified form of sural fasciocutaneous flap. METHODS: Ten patients (two female and eight male; median age 68 years, range 48-76) underwent reversed saphenous fasciocutaneous island flap after wide excision of heel lesion. The causes of heel lesions in all patients were Squamous Cell Carcinoma on the chronic burn's scar. In this new technique, sural nerve and artery were saved and blood supply to flap is based on lesser saphenous vein. Mean lesion surface was 60 cm(2) (range 30-112 cm(2)). RESULTS: Epidermolysis and flap discoloration were seen in three patients but treated with intermittent wet dressing and conservative managements. One patient showed partial necrosis in flap circumference which recovered with debridment and skin graft. Total flap necrosis was not seen in any patients. Mean hospital stay was 10 days (range 8-15 days). The mean follow up was 12 months (rang 6-18 months). CONCLUSION: Reversed saphenous fasciocutaneous island flap is an option for heel reconstruction. In contrast with sural flap, sural nerve and artery are saved.  相似文献   
34.

Objective

Sweat chloride measurement is considered a standard diagnostic tool for cystic fibrosis (CF). This study was performed to compare sweat chloride values obtained by quantitative pilocarpine iontophoresis (classic test) with sweat crystallization detected by direct observation of a drop of perspiration under light microscopy in patients with and without CF.

Methods

The tests using both techniques were performed simultaneously in patients with and without CF. Cutoff values of ≥60 mmol/L of chloride concentration for the classic sweat test was considered for diagnosis of CF. In crystallization method, observation of typical dendritic forms of salt crystals under light microscopy was interpreted positive.

Findings

Sixty patients suspected to CF (31 males and 29 females) with age range of 9 months to 2 years underwent the sweat test using both techniques. Median sweat chloride values was 26.13+10.85 in group with negative and 72.76+12.78 mmol/L in group with positive sweat test, respectively. All the patients who had positive sweat test in classic method showed typical dendritic forms of salt crystal in sweat crystallization test, which provided the test with 100% sensitivity (95%CI: 93.1–100). Only one of the 31 subjects with negative results for classic sweat test had positive result for crystallization sweat test, which provided the test with 96.7% specificity (95%CI: 92.9–100). Time spent to perform the crystallization test was significantly shorter than the classic method whereas its cost was also lower than the second method.

Conclusion

There was a good correspondence between two studied methods of sweat test. These results suggested the sweat crystallization test as an alternative test for detecting CF disease with high sensitivity and specificity.  相似文献   
35.
The functions of ghrelin, a novel weight-regulatory peptide, have not been intensively investigated in primitive fish. This experiment was conducted to determine whether ghrelin has a specific effect on growth hormone (GH), prolactin and cortisol levels in Persian sturgeon (Acipenser persicus). Juvenile Persian sturgeons with a mean body weight of 320?±?30?g were given a single injection of ghrelin at three doses of 0.1, 1 and 10?ng/g body weight. Control animals were injected with vehicle (sterile saline) only. Blood samples were collected at 0, 2, 4, 8, 24, 48 and 72?h after injection. The level of plasma hormones were determined by ELISA kit. As expected, ghrelin injection significantly elevated plasma GH (P?<?0.05), whereas prolactin levels did not significantly change after injection (P?>?0.05). Plasma cortisol levels decreased in fish injected with high doses of ghrelin (P?<?0.05). Ghrelin at 10?ng/g body weight had the most influence on GH release, and 1?ng/g ghrelin injection caused the lowest level of cortisol. These results show for the first time that ghrelin induces some plasma hormonal changes in sturgeon fish, as lower vertebrates, but more investigations are needed in this area.  相似文献   
36.

Objective

Reinfection rate of Helicobacter pylori after successful eradication is low in developed countries. This study was performed to determine the reinfection rate of H. pylori during a follow up period of 12 months in Iranian children.

Methods

In this prospective study, children with H. pylori infection were treated with triple omeprazole based regimen. Patients with negative 13C urea breath test (UBT) performed after 8 weeks of therapy, were followed up by the same test after 1 year.

Findings

Thirty seven patients, aged 5 to 17 years, were studied. Among them 25 (67.5%) were boys. After eradication therapy of H. pylori, 34 patients had negative 13C UBT. Reinfection occurred in 5 (14.7%) patients. Reappearance or continuing symptoms after treatment were associated with higher rate of recurrence (P=0.042).

Conclusion

Recurrence rate of H. pylori was high in our children. Successful eradication significantly decreased complaints and further symptoms. Follow up and reevaluation of patients is necessary especially when there are symptoms after eradication.  相似文献   
37.

Objective

Functional constipation is a common and challenging problem in pediatrics. Fecal disimpaction prior to maintenance therapy is recommended to ensure successful treatment. The aim of this study was to compare the efficacy and patient''s compliance of the two methods of paraffin oil administration (oral and rectal route) with the purpose of disimpaction in treatment of children with functional constipation.

Methods

A total of 80 children (49 males and 31 females) aged 1–12 years, with functional constipation according to Rome III criteria, whose rectal examination confirmed fecal impaction were divided into two groups randomly. Group I received 3 ml/kg/day paraffin oil orally and group II received 3ml/kg/day paraffin oil rectally during 3 consequent days. Successful treatment was defined as no detectable fecal impaction in rectal examination after at most 72 hours. Patient compliance and family satisfaction also was evaluated using a scored questionnaire.

Findings

Response to the treatment in both groups was with 92.5% and 82.5% in group I and II, respectively. So, there was no significant difference between the two methods of therapy. Family satisfying and compliance were obviously more achieved in group 1 (87.5% vs 57.5%) than in Group 2 (P<0.001). No parents in group I complained about type of treatment while 12.5% of parents in group II were unsatisfied with the mode of paraffin oil administration. The most common side effect of paraffin oil in both groups was anal oil seepage (27.5%). Nausea and abdominal pain were more common side effects in group 1 and 2 respectively.

Conclusion

It seems that using paraffin oil per oral route in comparison with rectal route could be a preferred option for disimpaction in children causing less anxiety to the family.  相似文献   
38.
BACKGROUND: Immediate loading of dental implants has been introduced as a method of reducing implant treatment time without compromising its prognosis. In this research, the effects of loading time on the amount of bone-to-implant contact and bone formation around dental implants were evaluated histologically. METHODS: Three months prior to implantation, the lower premolar teeth of 15 dogs were extracted. Three or four dental implants were placed in the healed extraction sites for each dog (N = 48). Dividing the dogs into three groups, the implants were either loaded 48 hours or 1 week later with metallic or prefabricated acrylic crowns or were left unloaded until the time of sacrifice. Three months after implant insertion, the animals were sacrificed and samples were investigated to define the amount of bone-to-implant contact, lamellar and woven bone percentage, and local inflammation of the newly formed bone. RESULTS: No significant difference in the observed criteria was reported among the three groups (P >0.05); however, the unloaded group had the highest degree of bone-to-implant contact and the group loaded 48 hours after the primary implant insertion had the least. The prosthesis type had no significant effect on the implant success rate (P >0.05). The lamellar and woven bone percentage of newly formed bone also did not differ in the three groups (P >0.05). One implant from each group failed in this study. CONCLUSION: Loading time does not seem to significantly affect the degree of osseointegration and bone-to-implant contact and the composition of newly formed bone around dental implants.  相似文献   
39.
40.
Multiple phase emulsions are increasingly used as alternatives to simple emulsions in personal care products. One of the major advantages of these emulsions over simple emulsions is slow and controlled release of their ingredients. Other favorite cosmetic characteristics of multiple emulsions include occlusivity (in O/W/O emulsions), esthetics and consumer acceptance.

Vitamin C (ascorbic acid) has been widely used in formulations of skin care products. Due to its effects on collagen biosynthesis, it is considered as moisturizing and anti-aging active ingredient. Instability problems such as oxidation susceptibility have made incorporating vitamin C in topical formulations a challenging issue.

The O/W/O emulsions have been formulated using two-step procedure, to investigate vitamin C stability and its release profile. By using different surfactant types and ratios, volume ratio of phases, multiple emulsions containing vitamin C were prepared.

Different parameters and formulation factors such as temperature of phases, duration and speed of mixing were evaluated. Based on our results, more stable emulsions were prepared from non-ionic siliconized surfactants, sorbitan derivatives and co–surfactants such as polyglyceryl derivatives. Physical stability was determined by microscopic examination, centrifugation and incubating emulsions in different temperatures.

Vitamin C in vitro release studies from O/W and O/W/O emulsions were conducted using Franz diffusion cell (at room temperature) and UV spectrophotometry. The results showed that in the first four-hour period, about 14% of vitamin C released from O/W/O emulsions. It appears that in multiple emulsions the profile of release follows zero-order kinetics. Our data indicate that incorporating vitamin C in multiple emulsions significantly increased its stability possibly attributed to the formation of reverse micelles of surfactants (and/or co-surfactants), which entrapped vitamin C inside the micelles surrounded by hydrophilic heads of surfactant. Moreover, vitamin C was released from multiple emulsions in a zero order slow and controlled release manner.  相似文献   
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