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51.
BACKGROUND: Phylogenetic analysis has been used widely to characterize extraintestinal pathogenic Escherichia coli in molecular epidemiological studies. We have recently reported a putative pathogenicity island (PAI), carrying uropathogenic-specific protein (usp) and a unique mosaic structure of small open reading frames following usp, providing four subtypes of PAIusp classified from their sequential patterns. METHODS: A total of 427 E. coli isolates from uncomplicated urinary tract infections (194 cystitis, 76 pyelonephritis, and 107 prostatitis) and 50 fecal isolates were examined for phylogenetic grouping and PAIusp subtyping as well as the prevalence of virulence factors (VF) and O serogroups. RESULTS: Both phylogenetic group B2 and usp-positive strains were equally predominant in cystitis, pyelonephritis and prostatitis (B2, 80.9%, 86.8%, and 86.9%; usp, 79.4%, 93.4%, and 88.8%, respectively). Furthermore, each PAIusp subtype was shown to be closely associated with several VF genes as well as several common O serogroups of uropathogenic E. coli. CONCLUSIONS: In molecular epidemiological studies, PAIusp subtyping will provide additional informative findings of E. coli strains belonging to phylogenetic group B2.  相似文献   
52.
1H and 13C nuclear magnetic resonance studies have been carried out on the linear, cyclic and polymeric peptides having a sequence of -Asp-ßAla-Gly-Ser-ßAla-Gly-His-ßAla-Gly-. From the 1 H spectra measured at 400 MHz, the rotamer populations about side chain Cα-Cß bond for Asp, Ser and His residues were estimated at pD 5 and 8. For Asp and Ser residues, the rotamers T (trans), G and G' (gauche) had an equivalent population at both pDs, while for His residue the rotamer G' had a higher probability than the others. 13C chemical shift of His and Asp residues measured at a frequency 15 MHz showed a considerable change in the pD ranges 3 ? 5 and 5 ? 8, respectively, owing to the ionizable side chains. The pK value for His residue, i.e. the midpoint of the chemical shift change, corresponded fairly well to that obtained from ester hydrolytic activity measurements, supporting the previous suggestion that the ester hydrolytic reaction is mainly controlled with the imidazole group of His residue. 13C spin-lattice relaxation time T1 was measured in order to investigate the molecular motion. It was found that the backbone was composed of relatively movable parts, -ßAla-Gly-, and less movable parts, Asp- Ser and His. Thisphenomenon was especially remarkable at the higher pD. The internal motion in the side chain was also investigated using the relaxation theory for the molecules undergoing the internal rotation. These results of relaxation measurements were compared with the results of conformational studies by circular dichroism measurements. The polymeric peptide composed only of -His-ßAla-Gly- sequence was also measured as a related peptide.  相似文献   
53.
We investigated the therapeutic effect and immunological action mechanism of IgG in experimental colitis induced by 3% dextran sulfate sodium in rats. Intravenous injection of homologous (rat) IgG (400 mg/kg per day) caused a significant suppression of occult blood discharge and ulcerative lesions in the colon, while no suppressive effect was observed in the case of heterologous (human) IgG. The positive effect of rat IgG on the lesions was also clearly shown by the histological examinations. Generation of proinflammatory cytokines, i.e. tumour necrosis factor-alpha (TNF-α) and IL-1α, in the lesions was found to be inhibited by administration of rat IgG. Little or no suppressive action was exerted by human IgG. Careful examination of recruited T cells and macrophages, both of which are thought to play important roles in the development of ulcerative colitis, indicated that rat IgG, but not its human counterpart, decreased the number of immunocompetent cells in colonic mucosa. Meanwhile, in an in vitro study, both forms of IgG were shown to suppress production of TNF-α and IL-1α from lamina propria mononuclear cells isolated from rat colon. These findings suggest that, mainly by suppressing recruitment of immunocompetent cells into the lesions, homologous IgG may reduce the occurrence of colitis.  相似文献   
54.
A 71-year-old man presented complaining of severe left flank pain. A computed tomography scan of the abdomen disclosed a left peripelvic extravasation of urine and a 4.0-cm abdominal aortic aneurysm with a significant amount of perianeurysmal thickening and prominent left hydroureter. The patient was diagnosed as having an inflammatory aneurysm of the abdominal aorta (IAAA) with peripelvic extravasations of urine. We report the results of a patient with IAAA with ureteral obstruction successfully treated with steroid therapy and a ureteral stent.  相似文献   
55.
56.
Although dermoscopy is used mainly for diagnosing pigmented skin lesions, this device has been reported to be useful in observing alopecia areata and frontal fibrosing alopecia. Herein, we investigated the dermoscopic features and their incidence of androgenetic alopecia (AGA; n  = 50 men) and female AGA (FAGA; n  = 10 women) in Asian people. More than 20% hair diameter diversity (HDD), which reportedly is an early sign of AGA and corresponds to hair follicle miniaturization, was observed in the affected area of all AGA and FAGA cases, suggesting that HDD is an essential feature to diagnose AGA and FAGA. Peripilar signs, corresponding to perifollicular pigmentation, were seen in 66% (33/50) of AGA and 20% (2/10) of FAGA women. This incidence in the present study was lower than previously reported in white subjects possibly because the Asian skin color conceals slight peripilar pigmentation. Yellow dots were observed in 26% (13/50) of AGA and 10% (1/10) of FAGA cases and the number of yellow dots in AGA and FAGA was limited to 10 on the overall hair loss area. Yellow dots possibly indicate the coincidence of AGA and enlargement of the sebaceous glands caused by common end-organ hypersensitivity to androgen. In conclusion, dermoscopy is useful to diagnose AGA and FAGA and provides insights into the pathogenesis of AGA.  相似文献   
57.
We reviewed reports about the postoperative course of hemifacial spasm (HFS) after microvascular decompression (MVD), including in our own patients, and investigated treatment for delayed resolution or recurrence of HFS. Symptoms of HFS disappear after surgery in many patients, but spasm persists postoperatively in about 10–40%. Residual spasm also gradually decreases, with rates of 1–13% at 1 year postoperatively. However, because delayed resolution is uncommon after 1 year postoperatively, the following is advised: (1) In patients with residual spasms after 1 year postoperatively (incomplete cure) or who again experience spasm ≥ 1 year postoperatively (recurrence), re-operation is recommended if the spasms are worse than before MVD. (2) When re-operation is considered, preoperative magnetic resonance imaging (MRI) findings and intraoperative videos should be reviewed to ensure that no compression due to a small artery or vein was missed, and to confirm that adhesions with the prosthesis are not causing compression. If any suspicious findings are identified, the cause must be eliminated. Moreover, because of the risk of nerve injury, decompression of the distal portion of the facial nerve should be performed only in patients in whom distal compression is strongly suspected to be the cause of symptoms. (3) Cure rates after re-operation are high, but complications such as hearing impairment and facial weakness have been reported in 10–20% of cases, so surgery must be performed with great care.  相似文献   
58.
Awake surgery could be a useful modality for lesions locating in close proximity to the eloquent areas including primary motor cortex and pyramidal tract. In case with supplementary motor area (SMA) lesion, we often encounter with intraoperative motor symptoms during awake surgery even in area without positive mapping. Although the usual recovery of the SMA syndrome has been well documented, rare cases with permanent deficits could be encountered in the clinical setting. It has been difficult to evaluate during surgery whether the intraoperative motor symptoms lead to postoperative permanent deficits. The purpose of this study was to demonstrate the intraoperative motor symptoms could be reversible, further to provide useful information for making decision to continue surgical procedure of tumor resection. Eight consecutive patients (from July 2012 to June 2014, six men and two women, aged 33–63 years) with neoplastic lesions around the SMA underwent an awake surgery. Using a retrospective analysis of intraoperative video records, intraoperative motor symptoms during tumor resection were investigated. In continuous functional monitoring during resection of SMA tumor under awake conditions, the following motor symptoms were observed during resection of the region without positive mapping: delayed motor weakness, delay of movement initiation, slowness of movement, difficulty in dual task response, and coordination disturbance. In seven patients hemiparesis observed immediately after surgery recovered to preoperative level within 6 weeks. During awake surgery for SMA tumors, the above-mentioned motor symptoms could occur in area without positive mapping and might be predictors for reversible SMA syndrome.  相似文献   
59.
The use of nanoparticles (NPs) has become a significant area of research in Dentistry.

Objective

The aim of this study was to investigate the physical, antibacterial activity and bond strength properties of conventional base, core build and restorative of glass ionomer cement (GIC) compared to GIC supplemented with titanium dioxide (TiO2) nanopowder at 3% and 5% (w/w).

Material and Methods

Vickers microhardness was estimated with diamond indenter. Compressive and flexural strengths were analyzed in a universal testing machine. Specimens were bonded to enamel and dentine, and tested for shear bond strength in a universal testing machine. Specimens were incubated with S. mutans suspension for evaluating antibacterial activity. Surface analysis of restorative conventional and modified GIC was performed with SEM and EDS. The analyses were carried out with Kolmogorov-Smirnov, ANOVA (post-hoc), Tukey test, Kruskal-Wallis, and Mann Whitney.

Results

Conventional GIC and GIC modified with TiO2 nanopowder for the base/liner cement and core build showed no differences for mechanical, antibacterial, and shear bond properties (p>0.05). In contrast, the supplementation of TiO2 NPs to restorative GIC significantly improved Vickers microhardness (p<0.05), flexural and compressive strength (p<0.05), and antibacterial activity (p<0.001), without interfering with adhesion to enamel and dentin.

Conclusion

GIC supplemented with TiO2 NPs (FX-II) is a promising material for restoration because of its potential antibacterial activity and durable restoration to withstand the mastication force.  相似文献   
60.
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