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1.
Quality of Life Research - The COVID-19 pandemic might add to the stressors experienced by people living with rheumatic diseases. This study aimed to examine rheumatic patients’ functional...  相似文献   
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PURPOSE: The purpose of this study was to compare the dentin/adhesive interfacial characteristics when bonding to noncarious as well as caries-affected dentin. MATERIALS AND METHODS: Seven extracted, unerupted, third molars were sectioned into halves. Artificial caries was created on one-half of each tooth, leaving the other half as a control. Dentin surfaces were treated with UNO adhesive according to the manufacturer's instructions for the wet-bonding technique and under environmental conditions present in the oral cavity. Dentin/adhesive interface sections of each half-tooth were stained with Goldner's trichrome, a classic bone stain, and examined using light microscopy. The width of exposed collagen was measured directly from photomicrographs, and adhesive penetration was analyzed qualitatively. RESULTS: The degree and extent to which the adhesive encapsulated the demineralized dentin matrix were reflected in the color difference in the stained sections with the noncarious dentin sections showing a degree of collagen encapsulation superior to that of the caries-affected dentin sections. The overall mean widths of exposed collagen were significantly (p < or = .05) greater at the caries-affected dentin/adhesive interface, 8.6 (1.7) microm, as compared with those at the noncarious dentin/adhesive interface, 6.0 (1.5) microm. CONCLUSIONS: The morphologic characteristics of the caries-affected dentin/interface suggest an increase in the exposed collagen zone and a decrease in the quality of the adhesive infiltration when compared with noncarious dentin. The evidence suggests that dentin substrate characteristics have a significant effect on the dentin/adhesive interface structure.  相似文献   
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Prepubertal periodontitis (PPP) is a rare and rapidly progressive disease of young children that results in destruction of the periodontal support of the primary dentition. The condition may occur as part of a recognised syndrome or may occur as an isolated finding. Both autosomal dominant and recessive forms of Mendelian transmission have been reported for PPP. We report a consanguineous Jordanian family with four members affected by PPP in two nuclear sibships. The parents of the affected subjects are first cousins. We have localised a gene of major effect for PPP in this kindred (Zmax=3.55 for D11S901 at θ=0.00) to a 14 cM genetic interval on chromosome 11q14 flanked by D11S916 and D11S1367. This PPP candidate interval overlaps the region of chromosome 11q14 that contains the cathepsin C gene responsible for Papillon-Lefèvre and Haim-Munk syndromes. Sequence analysis of the cathepsin C gene from PPP affected subjects from this Jordanian family indicated that all were homozygous for a missense mutation (1040A→G) that changes a tyrosine to a cysteine. All four parents were heterozygous carriers of this Tyr347Cys cathepsin C mutation. None of the family members who were heterozygous carriers for this mutation showed any clinical findings of PPP. None of the 50 controls tested were found to have this Tyr347Cys mutation. This is the first reported gene mutation for non-syndromic periodontitis and shows that non-syndromic PPP is an allelic variant of the type IV palmoplantar ectodermal dysplasias.


Keywords: prepubertal periodontitis; periodontal disease; cathepsin C; linkage  相似文献   
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The high affinity form of the human IL-2 receptor (IL-2R) has two known components, the IL-2R alpha (p55) and the IL-2R beta chain (p75). We have previously shown that recombinant IL-2 (rIL-2) could induce the expression of the alpha-chain (p55) on T cells and thymocytes, and increase this expression following suboptimal activation with concanavalin A (Con A) in combination with IL-2. An increase in the accumulation of IL-2R alpha-specific mRNA induced by rIL-2 in T cells and thymocytes had also been documented. We report here that the expression of IL-2R beta on the cell surface can be demonstrated on human thymocytes by the binding of Mik beta1, a MoAb directed against an epitope of the beta-chain. The IL-2R beta chain is constitutively expressed on freshly isolated thymocytes; this expression can be increased in thymocytes activated with Con A in combination with IL-2 or tetradecanoylphorbol 13-acetate (TPA). Blocking the formation of high affinity receptors with a MoAb directed against the alpha-chain of the receptor results in an increase in the display of IL-2R beta as evidenced by binding of MoAb Mik beta1. The accumulation of IL-2R-beta-specific mRNA is observed in freshly isolated thymocytes and it is increased in thymocytes cultured with rIL-2 alone, with Con A, and further enhanced by the addition of rIL-2 in combination with Con A or with TPA. Cyclosporine (CsA), which inhibits the accumulation of lymphokine-specific mRNA of thymocytes, does not inhibit the induction of the accumulation of IL-2R beta-specific mRNA. This is analogous to its effect on the expression of the alpha-chain (p55), and the accumulation of alpha-chain-specific mRNA.  相似文献   
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Diabetes mellitus is associated with increased risk of erectile dysfunction. Penile prosthesis implantation is an efficient therapeutic option for erectile dysfunction, but not without risk, as infection remains a prominent concern. This study investigates diabetes mellitus as a risk factor for penile prosthesis implantation infection and the relationship between haemoglobinA1c levels and infection rates. All diabetic patients with erectile dysfunction who underwent penile prosthesis implantation surgery between January 2012 and November 2019 at Hamad Medical Corporation, Qatar, were included in this retrospective observational study. A total of 599 diabetic patients with erectile dysfunction had penile prosthesis implantation. Mean age was 59.69 ± 31.19. Penile prosthesis implantation infection rate was 0.83% (5/599), while the mean haemoglobinA1c level was 7.58 ± 1.45 mmol/l (range: 4.1–12.6). A comparison between diabetic patients with penile prosthesis implantation infection and those without infection revealed no significant difference in the level of haemoglobinA1c between the two groups with mean haemoglobinA1c in patients with infected implants 7.14 and 7.59 for noninfected (p = 0.491). Limitations include retrospective single-centre design and low-infection rates reducing sample number. Penile prosthesis implantation infection rate in a large series of diabetic patients was low with no significant association between haemoglobinA1c level and penile prosthesis implantation infection observed.  相似文献   
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Clioquinol is a hydroxyquinoline antibiotic that has been associated with severe side-effects in the CNS. The syndrome caused by clioquinol treatment, subacute myelo-optic neuropathy (SMON), is considered as one of the worst drug disasters of this century. The precise biochemical mechanism behind SMON is not fully understood. Clioquinol can form strong lipophilic chelates with divalent cations and therefore it has been speculated that the drug may disturb the retention of vitamin B(12) through chelation of Co(2+). In the present study, the tissue distribution and uptake capacity of [57Co]cyanocobalamin were estimated in mice treated with clioquinol or saline. The concentrations of some trace metals were also determined in brain tissue. Accumulation of vitamin B(12) in the brain and its concentration in blood were decreased by clioquinol treatment. The mean concentrations of several trace metals were also lowered in the brain while the concentration of cobalt in the brain was not affected, suggesting that clioquinol does not bind to the cobalt in vitamin B(12). Moreover, a significant decrease in the levels of S-adenosylmethionine (SAM) was observed in the brain after clioquinol treatment. This may be a consequence of decreased vitamin B(12) levels. From these results, it can be concluded that chronic treatment with clioquinol may alter the tissue homeostasis of vitamin B(12) in the brain.  相似文献   
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