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991.
Infants with hypoplastic left heart syndrome (HLHS) are at risk for interstage morbidity and mortality, especially between the first and second surgical stages after the Norwood and hybrid procedures. This study compared the morbidity and mortality of patients treated by either the Norwood or the hybrid procedure for HLHS between the first and second stages who were undergoing interstage monitoring. Between October 2008 and December 2011, 26 infants (14 boys) with HLHS (n = 16) and other univentricular heart malformations with aortic arch anomaly (n = 10) were scheduled for interstage monitoring after Norwood I (n = 12) and hybrid (n = 14) procedures. Three infants (11.5 %) died after first-stage palliation (one hybrid patient and two Norwood patients), and three infants (11.5 %) died after second-stage palliation (two hybrid patients and one Norwood patient) (p = 0.83), all after early second-stage surgery (<90 days). The Norwood I and hybrid procedures did not differ in terms of overall mortality (23 %) (three hybrid and three Norwood patients; p = 1.00). Seven infants (26.9 %) could not be discharged from the hospital due to hemodynamic instability and were referred for early second-stage surgery (<90 days). After the first stage, the invasive reevaluation rate before discharge was high (53.8 %), with cardiac catheterizations for 8 of 14 patients after the hybrid procedure and for 6 of 12 patients after the Norwood procedure (p = 0.69). A total of 11 reinterventions were performed (eight by catheter and three by surgery). Of the eight catheter reinterventions, five were performed for hybrid patients (p = 0.22). For 14 infants, 89 days (range 10–177 days) of interstage monitoring were scheduled. One infant (3.9 %) died during the interstage monitoring. The findings showed a breach of the physiologic criteria for interstage monitoring in seven infants (50 %) after 10 days (range 4–68 days) (five hybrid and two Norwood patients), leading to rehospitalization and catheterization for six patients (four hybrid and two Norwood patients), requiring interventions for two patients (patent arterial duct stent dilation, and atrial septal defect stenting, all for hybrid patients). Overall, three of the seven patients with red flag events of interstage monitoring were candidates for early second-stage surgery. In conclusion, morbidity among infants treated for HLHS remains high, either before or after hospital discharge, emphasizing the need of interstage monitoring programs. Despite retrograde aortic flow in infants with HLHS after the hybrid procedure, the mortality rate was comparable between the two groups. Mortality occurs after early second-stage surgery (<90 days).  相似文献   
992.
993.
994.

Introduction

Sodium hypochlorite (NaOCl) irrigation is critical to endodontic success, and several new methods have been developed to improve irrigation efficacy (eg, passive ultrasonic irrigation [PUI] and EndoActivator [EA]). Using a novel spectrophotometric method, this study evaluated NaOCl irrigant extrusion during canal irrigation.

Methods

One hundred fourteen single-rooted extracted teeth were decoronated to leave 15 mm of the root length for each tooth. Cleaning and shaping of the teeth were completed using standardized hand and rotary instrumentation to an apical file size #40/0.04 taper. Roots were sealed (not apex), and 54 straight roots (n = 18/group) and 60 curved roots (>20° curvature, n = 20/group) were included. Teeth were irrigated with 5.25% NaOCl by 1 of 3 methods: passive irrigation with needle, PUI, or EA irrigation. Extrusion of NaOCl was evaluated using a pH indicator and a spectrophotometer. Standard curves were prepared with known amounts of irrigant to quantify amounts in unknown samples.

Results

Irrigant extrusion was minimal with all methods, with most teeth showing no NaOCl extrusion in straight or curved roots. Minor NaOCl extrusion (1–3 μL) in straight roots or curved roots occurred in 10%–11% of teeth in all 3 irrigant methods. Two teeth in both the syringe irrigation and the EA group extruded 3–10 μL of NaOCl.

Conclusions

The spectrophotometric method used in this study proved to be very sensitive while providing quantification of the irrigant levels extruded. Using the PUI or EA tip to within 1 mm of the working length appears to be fairly safe, but apical anatomy can vary in teeth to allow extrusion of irrigant.  相似文献   
995.

Objective

The aim of the present study was to analyze in vitro the combinatorial effects of the antibiotic combination of amoxicillin plus metronidazole on subgingival bacterial isolates.

Design

Aggregatibacter (Actinobacillus) actinomycetemcomitans, Prevotella intermedia/nigrescens, Fusobacterium nucleatum and Eikenella corrodens from our strain collection and subgingival bacteria isolated from patients with periodontitis were tested for their susceptibility to amoxicillin and metronidazole using the Etest. The fractional inhibitory concentration index (FICI), which is commonly used to describe drug interactions, was calculated.

Results

Synergy, i.e. FICI values ≤ 0.5, between amoxicillin and metronidazole was shown for two A. actinomycetemcomitans (FICI: 0.3), two F. nucleatum (FICI: 0.3 and 0.5, respectively) and one E. corrodens (FICI: 0.4) isolates. Indifference, i.e. FIC indices of >0.5 but ≤4, occurred for other isolates and the 14 P. intermedia/nigrescens strains tested. Microorganisms resistant to either amoxicillin or metronidazole were detected in all samples by Etest.

Conclusion

Combinatorial effects occur between amoxicillin and metronidazole on some strains of A. actinomycetemcomitans, F. nucleatum and E. corrodens. Synergy was shown for a few strains only.  相似文献   
996.
The scapula free flap is often the first choice for reconstruction of bony defects of the facial skeleton. However, the vascularised rib as part of a free rib osteomyocutaneous flap may be a suitable second choice. We have investigated the morphology and clinical dimensions of the 7th rib and the scapula, and the ability of the available bone to carry dental implants. The age and sex of the cadaver, and the donor side, were also recorded. The dimensions of the scapulas and 7th ribs (n = 130 of each) from 65 cadavers were measured at 4 different points using osteometric methods. Examination showed that bone from the scapula and 7th rib were sufficient for placement of implants. The 7th rib gave reliable measurements for both height and width, and a consistent relation between compact and cancellous bone. Although the scapula provided adequate compact and cancellous bone, there were variations depending on the segment of bone chosen. Bones from male cadavers were more suitable for implantation. In both the scapula and the 7th rib ageing had a significant adverse effect in only one dimension. Most points of measurement have satisfactory bony dimensions for insertion of dental implants.  相似文献   
997.
998.
In this longitudinal study, we examined the stability of the association between executive functions and externalizing behavior problems, and the developmental change of executive functions in a predominately clinically diagnosed preschool sample (N = 200). Inhibition and working memory performance were assessed three times in 18 months. Across time, poorer inhibition performance in young children was associated with attention deficit hyperactivity disorder (ADHD) and disruptive behavior disorders (DBD), and poorer working memory performance was associated with ADHD. Inhibition and working memory performance increased over time, especially in the early preschool period. The improvement of inhibition performance was more pronounced in the clinically diagnosed children compared to the TD children.  相似文献   
999.

Objectives

Mechanical loading is a potential activator of inflammation and able to stimulate factors for periodontal and alveolar bone destruction. Aim of this study was to investigate the inflammatory response and synthesis of proteinases by human periodontal ligament fibroblast (HPdLF) dependent on different strengths of static tensile strain (STS).

Materials and methods

HPdLFs were loaded with different STS strengths (1, 5, and 10 %) in vitro. Gene expressions of cyclooxygenase (COX)-2 and interleukin (IL)-6 were analyzed by quantitative real-time polymerase chain reaction. Production of IL-6, prostaglandin E2 (PGE2), matrix metalloproteinase (MMP)-8, and tissue inhibitors of matrix metalloproteinase (TIMP)-1 were measured by enzyme-linked immunosorbent assay. Receptor activator of nuclear factor-kappa ligand (RANKL) synthesis was detected by immunocytochemical staining.

Results

Ten percent STS led to an increased gene expression of IL-6 and COX-2 (34.4-fold) in HPdLF, and 1 and 5 % STS slightly reduced the gene expression of IL-6. Synthesis of IL-6 was significantly reduced by 1 % STS and stimulated by 10 % STS. Ten percent STS significantly induced PGE2 production. RANKL was not detectable at any strength of STS. MMP-8 synthesis showed significantly higher values only at 10 % STS, but TIMP-1 was stimulated by 5 and 10 % STS, resulting into highest TIMP-1/MMP-8 ratio at 5 % STS.

Conclusions

High-strength STS is a potent inducer of periodontal inflammation and MMP-8, whereas low-strength STS shows an anti-inflammatory effect. Moderate-strength STS causes the highest TIMP-1/MMP-8 ratio, leading to appropriate conditions for reformation of the extracellular matrix.

Clinical relevance

Furthermore, this study points out that the strength of force plays a pivotal role to achieve orthodontic tooth movement without inducing periodontal inflammation and to activate extracellular matrix regeneration.  相似文献   
1000.

Objectives

The aim of this study was to evaluate the efficacy of four different powered toothbrushes with side-to-side action for noncontact biofilm removal in vitro.

Materials and methods

A three-species biofilm was formed in vitro on protein-coated titanium disks using a flow chamber combined with a static biofilm growth model. Subsequently, the biofilm-coated substrates were exposed to four different side-to-side toothbrushes (A, B, C, and D) with various brushing times (2, 4, and 6 s) and brushing (bristle-to-disk) distances (0, 2, and 4 mm). The biofilm volumes were measured using volumetric analyses with confocal laser scanning microscope images and Imaris version 7.5.2 software.

Results

The median percentages of biofilm reduction by the analyzed toothbrushes ranged from 9 % to 80 %. The abilities of the tested toothbrushes to remove the in vitro biofilm differed significantly (p?<?0.05). Two of the tested toothbrushes (C and D) were capable of significant biofilm reduction by noncontact brushing.

Conclusions

It was possible to reduce a three-species in vitro biofilm by noncontact brushing with two out of four side-to-side toothbrushes.

Clinical relevance

Toothbrushes C and D show in vitro a high efficacy in biofilm removal without bristle contact.  相似文献   
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