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91.
ObjectivesTo evaluate the effect of orthodontic appliances on physicochemical, biochemical, and oxidative stress changes in salivary parameters during treatment.Materials and MethodsA cohort study was conducted with 112 healthy patients. Salivary samples were taken at baseline, 1 month, and 9 months after placement of the orthodontic appliances used in treatment.ResultsA statistically significant difference was observed in certain examined salivary parameters, including enzymes, electrolytes, and oxidative stress markers.ConclusionsThe use of aligners had a lower prevalence of disturbing salivary parameters. Orthodontist must consider these changes to prevent the occurrence of white spot lesions.  相似文献   
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A newly produced murine recombinant angiotensin (Ang)-converting enzyme 2 (ACE2) was characterized in vivo and in vitro. The effects of available ACE2 inhibitors (MLN-4760 and 2 conformational variants of DX600, linear and cyclic) were also examined. When murine ACE2 was given to mice for 4 weeks, a marked increase in serum ACE2 activity was sustainable. In acute studies, mouse ACE2 (1 mg/kg) obliterated hypertension induced by Ang II infusion by rapidly decreasing plasma Ang II. These effects were blocked by MLN-4760 but not by either form of DX600. In vitro, conversion from Ang II to Ang-(1-7) by mouse ACE2 was blocked by MLN-4760 (10(-6) m) but not by either form of DX600 (10(-5) m). Quantitative analysis of multiple Ang peptides in plasma ex vivo revealed formation of Ang-(1-9) from Ang I by human but not by mouse ACE2. Both human and mouse ACE2 led to the dissipation of Ang II with formation of Ang (1-7). By contrast, mouse ACE2-driven Ang-(1-7) formation from Ang II was blocked by MLN-4760 but not by either linear or cyclic DX600. In conclusion, sustained elevations in serum ACE2 activity can be accomplished with murine ACE2 administration, thereby providing a strategy for ACE2 amplification in chronic studies using rodent models of hypertension and cardiovascular disease. Human but not mouse ACE2 degrades Ang I to form Ang-(1-9). There are also species differences regarding rodent and human ACE2 inhibition by known inhibitors such that MLN-4760 inhibits both human and mouse ACE2, whereas DX600 only blocks human ACE2 activity.  相似文献   
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We determined the complete nucleotide sequence of the Rose spring dwarf-associated virus (RSDaV) genomic RNA (GenBank accession no. EU024678) and compared its predicted RNA structural characteristics affecting gene expression. A cDNA library was derived from RSDaV double-stranded RNAs (dsRNAs) purified from infected tissue. Nucleotide sequence analysis of the cloned cDNAs, plus for clones generated by 5'- and 3'-RACE showed the RSDaV genomic RNA to be 5808 nucleotides. The genomic RNA contains five major open reading frames (ORFs), and three small ORFs in the 3'-terminal 800 nucleotides, typical for viruses of genus Luteovirus in the family Luteoviridae. Northern blot hybridization analysis revealed the genomic RNA and two prominent subgenomic RNAs of approximately 3 kb and 1 kb. Putative 5' ends of the sgRNAs were predicted by identification of conserved sequences and secondary structures which resembled the Barley yellow dwarf virus (BYDV) genomic RNA 5' end and subgenomic RNA promoter sequences. Secondary structures of the BYDV-like ribosomal frameshift elements and cap-independent translation elements, including long-distance base pairing spanning four kb were identified. These contain similarities but also informative differences with the BYDV structures, including a strikingly different structure predicted for the 3' cap-independent translation element. These analyses of the RSDaV genomic RNA show more complexity for the RNA structural elements for members of the Luteoviridae.  相似文献   
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Angiogenesis has a significant pathogenic role in liver damage-associated hepatitis C virus infection. We evaluated whether chronic hepatitis C (CHC) is associated with elevated levels of angiogenesis marker (vascular endothelial growth factor) and whether it is modulated by therapy. Vascular endothelial growth factor (VEGF) mRNA was determined in the 36 CHC patients included in this study before therapy and 12 weeks after receiving antiviral combination therapy, pegylated interferon alpha-2b plus ribavirin, compared to 20 healthy controls. CHC patients showed elevated baseline VEGF level before and during treatment, but it was decreased in responder group, indicating a shift toward an “anti-angiogenic” process in CHC patients. In conclusion, this suggests that VEGF mRNA level could be useful as non-invasive, base markers of response to therapy.  相似文献   
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IntroductionUrinary incontinence impairs sexual functioning and sexual satisfaction. Traditional artificial urinary sphincter (AUS) implantation requires perineal incision for cuff placement and a second inguinal incision for reservoir and pump placement. We believed AUS could be placed easier and quicker through one scrotal incision.AimIn an effort to effect more proximal placement of the cuff while keeping the advantages of the one scrotal incision technique, we report enhancements to the original surgical technique.MethodsThirty patients have been operated upon using the enhanced technique. A modification of the SKW retractor system (AMS) facilitates deep bulbar exposure. Twenty patients were first time implantations and 10 were revisions with five of the revisions having had the original AUS placed by traditional two-incision technique. Two of the first time AUS patients received an inflatable penile prosthesis through the same incision.Main Outcome MeasuresWe evaluated site of cuff placement, sizes of cuffs used, postoperative continence status.ResultsAll of the virgin AUS required dissection of the bulbocavernosus muscle prior to cuff placement. In scrotally placed revisions, replacement cuffs were situated considerably proximal (4.5–7.5 cm) to the original cuff site. The perineal placed revisions were accomplished through a scrotal incision with replacement of two cuffs in the same site and the three other patients immediately distal. No intraoperative complications were seen. One patient developed scrotal hematoma requiring drainage. Only 15 patients are available for follow-up and all are socially continent (one pad or less).ConclusionsTransscrotal approach is used safely and efficiently for penile implants and AUS implantation. The new enhancements to the one-scrotal incision technique allow more proximal cuff placement as evidenced by the bulbocavernosus muscle dissection and use of larger cuffs. Continence rate is similar to rates achieved with perineal placement of cuff found in the literature. Wilson SK, Aliotta PJ, Salem EA, and Mulcahy JJ. New enhancements of the scrotal one incision technique for placement of artificial urinary sphincter allow proximal cuff placement.  相似文献   
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Infectious complications after yttrium-90 (y-90) radioembolization of hepatic tumors are rare. Most reports describe hepatic abscesses as complications of other locoregional therapies, such as transcatheter arterial embolization or chemoembolization. These usually occur in patients with a history of biliary intervention and present several weeks after treatment. We report a case of hepatic abscess formed immediately after y-90 radioembolization of a hepatic metastasis in a patient who had no history of previous biliary instrumentation.  相似文献   
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