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101.
An increased prevalence of immunoglobulin (Ig) A deficiency has been documented in a number of autoimmune diseases; however, its association with type 1 diabetes mellitus (DM1) is a subject of debate. This study was performed to evaluate serum IgA levels in a group of pediatric patients with DM1. Three hundred patients with mean age of 12.6 ± 6.7 years were enrolled in this study. Serum IgA and other immunoglobulins levels were measured using enzyme-linked immunosorbant assay. Mean serum IgA level of patients was 271.0 ± 141.4 mg/dl. Only two patients had IgA deficiency (IgA < 10 mg/dl), who were two boys with ages of 9 and 10 years. Although associated autoimmune disorders were found in a number of patients with DM1, no other autoimmune disorder was detected in these two patients with IgA deficiency. Serum levels of all other immunoglobulins were normal. Serum IgA levels did not significantly differ by grouping the patients according to age variation, sex distribution, disease duration, and associated disorders. There was no significant correlation between IgA levels and hemoglobin A1c. This study showed the prevalence of IgA deficiency in Iranian patients with DM1 as 0.7% (1:150), which is much higher than reported prevalences in general populations. Further studies are needed for better understanding the possible etiologies of increased IgA deficiency in DM1 and its effects on diabetes control.  相似文献   
102.
Bardet‐Biedl syndrome (BBS) is a group of autosomal recessive MCA/MR syndromes characterized by pigmentary retinopathy, postaxial polydactyly, hypogenitalism, obesity, and mental retardation. Five BBS loci have been identified; among them, BBS type 1 (BBS1) and type 3 (BBS3) are most common and most rare, respectively. We encountered an Iranian family that had seven affected members. All patients had a history of mild to severe obesity, but it was reversible in some patients by caloric restriction and exercise. All patients had pigmentary retinopathy, beginning as night blindness in early childhood and progressing toward severe impairment of vision by the end of the second decade. Polydactyly varied in limb distribution, ranging from four‐limb involvement to random involvement or even to nonaffectedness. Six of the seven patients were not mentally retarded. Although kidney anomaly or an adrenal mass was pres‐ ent in two patients, the fact that one patient had seven children rules out reproductive dysfunction. Linkage analysis with microsatellite markers showed that the disease in the family was assigned to a region around marker loci at 3p13‐p12 (maximum LOD score = 4.15 and recombination fraction θ = 0, at D3S1603 microsatellite marker), to which the BBS3 locus has been mapped. Haplotype analysis did not reduce the extent of the previously reported critical region of BBS3. A comparison of clinical manifestations of our patients with those of previously reported BBS3 patients did not support any type‐specific phenotypes, though manifestations in our patients are similar to those in BBS3 patients of a family in Newfoundland. Am. J. Med. Genet. 94:433–437, 2000. © 2000 Wiley‐Liss, Inc.  相似文献   
103.
Nitric oxide (NO) derived from activated macrophages has been shown to be crucial for the host's leishmanicidal activities. Excess NO, however, can induce apoptosis in some cell types, including macrophages. In the present investigation, we studied the role of NO in inducing apoptosis of BALB/c mice macrophages infected with Leishmania major in vitro. The peritoneal macrophages were harvested and cultured with or without L.major in the presence of a donating reagent (s-Nitroso-N-Acetylpenicillamine (SNAP)) or an inhibitor of NO synthase (NG -Methyl-L-Arginine (NMMA)). The concentration of NO in culture supernatants was measured after 18 hours incubation. Simultaneously, macrophages undergoing apoptosis were identified by fluorescence and electron microscopy. The results showed an increase in apoptosis rate in parallel to nitrite production in macrophages cultured in the presence of SNAP. Although macrophages infected with L.major had no significant increase in NO production, they showed a significant increase in apoptosis rate. Besides, macrophages cultured with NMMA, had a decreased NO production but the apoptosis rate increased. Therefore, mechanisms involved in apoptosis induction in the last two groups may be different from NO overproduction.  相似文献   
104.
Transforming growth factor beta‐3 (TGF‐β3) has been shown to decrease scar formation after scheduled topical applications to the cutaneous wounds. This study aimed to continuously deliver TGF‐β3, during the early phase of wound healing, by engineering a dermal equivalent (DE) using TGF‐β3 expressing bone marrow stromal cells (BM‐SCs) and human dehydrated amniotic membrane (hDAM). To engineer a DE, rat BM‐SCs were seeded on the hDAM and TGF‐β3 was transiently transfected into the BM‐SCs using a plasmid vector. Pieces of the dermal equivalent were transplanted onto the full‐thickness excisional skin wounds in rats. The process of wound healing was assessed by image analysis, Manchester Scar Scale (MSS), and histopathological studies 7, 14, 21, and 85 days after the excision. The results confirmed accurate construction of recombinant pcDNA3.1‐TGF‐β3 expression system and showed that the transfected BM‐SCs seeded on hDAM expressed TGF‐β3 mRNA and protein from day 3 through day 7 after transfection. After implantation of the DE, contraction of the wounds was measured from day 7 through 21 and analyzed by linear regression, which revealed that the rate of wound contraction in all experimental groups was similar. Histologic evaluation demonstrated that transfected BM‐SCs decreased retention and recruitment of the cells during the early stage of wound healing, decreased the formation of vascular structures and led to formation of uniformly parallel collagen bundles. MSS scores showed that TGF‐β3 secreting cells significantly improved the cosmetic appearance of the healed skin and decreased the scar formation. From these results, it could be concluded that transient secretion of TGF‐β3, during the early phase of healing, by BM‐SCs seeded on hDAM can improve the cosmetic appearance of the scar in cutaneous wounds without negatively affecting the process of wound repair.  相似文献   
105.
BACKGROUND: Iron deficiency is the most common cause of anemia in children. Recently there has been evidence to suggest a relationship between Helicobacter pylori gastritis and iron deficiency anemia. Because both H. pylori infection and iron-deficiency anemia are common in children, we studied any correlation between H. pylori infection and iron-deficiency anemia in children. METHOD: In a case-control study at the Children's Medical Center Hospital, 100 children with H. pylori infection and 109 children without infection according to histology were evaluated. Iron-deficiency anemia was diagnosed when serum ferritin and hemoglobin levels were less than adjusted values for age and sex. RESULTS: There were 111 boys and 98 girls with a median age of 7.1 years. The main symptom was abdominal pain in H. pylori-infected and non-infected patients. Frequency of H. pylori infection in anemic and non-anemic patients was nearly similar (43.9 and 50.4%, respectively). Among patients with H. pylori, 36% had anemia and in patient without H. pylori infection, its frequency was 42.2% (p = 0.59). Among patients with H. pylori, 19% had iron-deficiency anemia and in patients without H. pylori infection, its frequency was 21.1% (p = 0.7). Among patients with H. pylori, the difference between the severity of gastritis in those with anemia and those without anemia was not statistically significant (p = 0.382) and no correlation was found between degree of H. pylori colonization and anemia. CONCLUSIONS: Our results do not support the proposal that H. pylori infection is associated with iron-deficiency anemia in children. Further studies emphasizing the socioeconomic status of children, evaluation of strains of H. pylori, and posttreatment measurement of serum iron and serum ferritin are necessary to show the possible association.  相似文献   
106.
Sarcoptes scabiei infestation was diagnosed in four freshly dead and three net-captured gazelle while ranging freely. The captured animals presented with an alopecic pruritic skin disease with signs of crusted skin lesions, numerous small nodules which first appeared on the lips or nostrils and then it also extended towards the eyelids, around the ears, and, in some cases, over entire face, neck, trunk, and legs. Skin over the affected area gradually became bald, thick and hard, being dry and doughy to the touch, and serous fluid or sometimes blood oozes from the lesions which had a severe malodor. Skin scrapings confirmed the presence of the mite S. scabiei. Histopathology of lesions demonstrated marked acanthosis, hyperkeratosis, and parakeratosis. Microscopical examination also revealed all stages of S. scabiei, which were located mainly in the stratum corneum and also in the stratum granulosum. During the capture and sampling of the animals, four persons ranging in age from 25 to 62 years were exposed to scabies. Two relatives of one of them have been also affected by familiar contact. Clinical signs appeared within 9 days of exposure. They developed several pruretic erythematous papules with intense itching.  相似文献   
107.
The aim of the present study was the evaluation of the efficacy of open flap debridement (OFD) with and without enamel matrix derivatives (EMD) in the management of class II furcation involvement. Twenty similar bilateral class II furcation defects in ten healthy nonsmoker patients were selected. One defect in each subject was treated with OFD alone (OFD group) and the contralateral one with OFD and simultaneous application of enamel matrix derivatives (EMD group). Clinical probing depth, vertical clinical attachment level, horizontal clinical attachment level, and the location of the gingival margin, horizontal probing depth of bony defect (E-HPD), vertical depth of bone crest, vertical depth of the base of bony defect (V-DBD), and length of the intrabony defect were measured at baseline and during reentry surgery after 6 months. Wilcoxon signed-rank test and Mann-Whitney U test were used to analyze the data. Among soft tissue parameters, only horizontal attachment gain in EMD was significantly more than OFD (P = 0.002). Application of EMD significantly enhanced the horizontal (E-HPD) and vertical (V-DBD) resolution of the bony defect (P < 0.05). In conclusion, it seems that the adjunctive use of EMD enhances the efficiency of OFD in the management of mandibular class II furcation defects.  相似文献   
108.
Background: Phenytoin, a widely used anticonvulsant, interacts with many drugs. These interactions may be clinically significant.Objective: This controlled, 31-day study investigated the possible interactions of phenytoin with urethane and ascorbic acid.Methods: Groups of male rats were subjected to long-term oral phenytoin treatment with or without ascorbic acid coadministration. The responsiveness of treated animals to the anesthetic activity of urethane then was investigated by assessing their righting reflexes.Results: Long-term phenytoin treatment resulted in hyporesponsiveness to the urethane anesthetic effect, and this interaction was augmented by ascorbic acid coadministration.Conclusion: Our results indicate that phenytoin interacts with ascorbic acid and urethane in vivo, which may be of clinical and/or experimental importance.  相似文献   
109.

Objective:

Ellagic acid (EA), a major polyphenolic compound of pomegranate juice, produces antinociceptive effects, which are mediated through opioidergic and nitric oxide-cyclic guanosine monophosphate (NO-cGMP) pathways. The present study was conducted to elucidate the peripheral antinociceptive effect of EA alone and in combination with sildenafil in the rat formalin test.

Materials and Methods:

Pain was produced by intraplantar injection of formalin (2.5%) in rats and nociceptive behavior was measured as the number of flinches every 5 min in 60 min after injection.

Results:

Local administration of EA and sildenafil dose-dependently increased the nociception threshold in both phases of the test. Moreover, sub-effective doses of sildenafil (25 or 50 mcg/paw, i.p.) significantly and dose-dependently enhanced the antinociception induced by a sub-effective dose of EA (60 mcg/paw, i.pl.) in both phases of the test. The antinociception produced by these drugs alone, or in combination, was due to a peripheral site of action, since the administration in the contralateral paw was ineffective.

Conclusion:

Our results suggest that EA has local peripheral antinociceptive activity, and enhancement of this effect with sildenafil probably occurs through the inhibition of cGMP metabolism.KEY WORDS: Ellagic acid, formalin, peripheral antinociception, sildenafil  相似文献   
110.
The aim of this study was to quantify the dose enhancement by gadolinium and gold nanoparticles in brachytherapy. MCNPX Monte Carlo code was used to simulate four brachytherapy sources: (60)Co, (198)Au, (192)Ir, (169)Yb. To verify the accuracy of our simulations, the obtained values of dose rate constants and radial dose functions were compared with corresponding published values for these sources. To study dose enhancements, a spherical soft tissue phantom with 15 cm in radius was simulated. Gadolinium and gold nanoparticles at 10, 20 and 30 mg/ml concentrations were separately assumed in a 1 × 1 × 1 cm(3) volume simulating tumour. The simulated dose to the tumour with the impurity was compared to the dose without impurity, as a function of radial distance and concentration of the impurity, to determine the enhancement of dose due to the presence of the impurity. Dose enhancements in the tumour obtained in the presence of gadolinium and gold nanoparticles with concentration of 30 mg/ml, were found to be in the range of -0.5-106.1 and 0.4-153.1 % respectively. In addition, at higher radial distances from the source center, higher dose enhancements were observed. GdNPs can be used as a high atomic number material to enhance dose in tumour volume with dose enhancements up to 106.1 % when used in brachytherapy. Regardless considering the clinical limitations of the here-in presented model, for a similar source and concentration of nanoparticles, gold nanoparticles show higher dose enhancement than gadolinium nanoparticles and can have more clinical usefulness as dose enhancer material.  相似文献   
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