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21.

Purpose

Disturbed iron homeostasis contributes to resistance to recombinant human erythropoietin (rHuEpo) in hemodialysis (HD) patients. Increased hepcidin, which downregulates the iron exporter ferroportin, has been incriminated. However, other factors also control ferroportin expression in mononuclear phagocyte system. Ferroportin in monocytes, as well as serum hepcidin, interleukin-6 (IL-6) and common markers of iron status were measured and correlations with rHuEpo resistance index (ERI) were evaluated.

Methods

After a 4-week washout period from iron treatment, 34 HD patients and 20 healthy volunteers enrolled in the study. Ferroportin was assessed by means of western blotting, whereas hepcidin and IL-6 with enzyme-linked immunosorbent assay. Hemoglobin, serum iron, ferritin and transferrin saturation (TSAT) were also measured.

Results

Ferroportin in monocytes of HD patients was decreased. Serum hepcidin and IL-6 were increased, whereas serum iron and TSAT were decreased. ERI was negatively correlated with ferroportin and all the markers of iron adequacy, but not with hepcidin.

Conclusion

Decreased ferroportin in monocytes of HD patients accompanies increased hepcidin, inflammation, decreased iron availability and is correlated with resistance to rHuEpo treatment.  相似文献   
22.
The association between tumor size and survival in patients with intrahepatic cholangiocarcinoma (ICC) undergoing surgical resection is controversial. We sought to define the incidence of major and microscopic vascular invasion relative to ICC tumor size, and identify predictors of microscopic vascular invasion in patients with ICC ≥5 cm. A total of 443 patients undergoing surgical resection for ICC between 1973 and 2011 at one of 11 participating institutions were identified. Clinical and pathologic data were evaluated using uni- and multivariate analyses. As tumor sized increased, the incidence of microscopic vascular invasion increased: <3 cm, 3.6 %; 3–5 cm, 24.7 %; 5–7 cm, 38.3 %; 7–15 cm, 32.9 %, ≥15 cm, 55.6 %; (p?<?0.001). Increasing tumor size was also found to be associated with worsening tumor grade. The incidence of poorly differentiated tumors increased with increasing ICC tumor size: <3 cm, 9.7 %; 3–5 cm, 19.8 %; 5–7 cm, 24.2 %; 7–15 cm, 21.1 %; >15 cm, 31.6 % (p?=?0.04). The presence of perineural invasion (odds ratio [OR]?=?2.98) and regional lymph node metastasis (OR?=?4.43) were independently associated with an increased risk of microscopic vascular invasion in tumors ≥5 cm (both p?<?0.05). Risk of microscopic vascular invasion and worse tumor grade increased with tumor size. Large tumors likely harbor worse pathologic features; this information should be considered when determining therapy and prognosis of patients with large ICC.  相似文献   
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Introduction

Effective root canal disinfection is a fundamental component of successful root canal treatment. Photodynamic therapy (PDT) has been proposed as a new adjunctive method for additional disinfection of the root canal system with the possibility of improved treatment outcomes. The aim of this systematic review was to investigate the effect of PDT on bacterial load reduction during root canal disinfection.

Methods

Two reviewers independently conducted a comprehensive literature search using a combination of medical subject heading terms and key words to identify studies relevant to the Population Intervention Control Outcome question. The selection of articles for inclusion was performed in 2 phases based on predetermined eligibility criteria according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Inter-reviewer agreement for each phase was recorded. The effect of PDT on bacterial load reduction during root canal disinfection was evaluated as the primary outcome variable during data extraction.

Results

The literature search provided 57 titles and abstracts. Three articles met the inclusion criteria and were selected for this systematic review. The reasons for study exclusion in each phase were recorded. Because of the heterogeneity in clinical indications and PDT protocols among the included studies, a meta-analysis could not be performed. All included studies showed a positive effect of PDT in the reduction of microbial load in root canal treatment ranging from 91.3%–100%.

Conclusions

Limited clinical information is currently available on the use of PDT in root canal disinfection. If supported by future clinical research, PDT may have efficacy for additional root canal disinfection, especially in the presence of multi–drug-resistant bacteria.  相似文献   
25.
Perioperative liver graft injury is associated with elevation of aminotransferases after orthotopic liver transplantation (OLT). Values above 5000 U/l usually are regarded as extreme liver graft injury (ELGI). Some patients and organs recover from this critical condition. The aim of the study was to evaluate factors contributing to graft and patient survival after ELGI. From chart review we identified 64 of 917 OLT adult patients (median age 54.2 years; 68.8% males) transplanted between 11/2003 and 02/2012, who presented ELGI after OLT. Donor and recipient factors were analyzed and correlated with the outcome by univariable and multivariable methods. Multivariable cox proportional hazards showed that recipient's BMI (P = 0.01), model for end stage liver disease (MELD) score before OLT (P = 0.02) and laboratory MELD score 24 h after OLT (P = 0.01) were independently associated with patient survival. 30‐days and 12‐months survival in patients with a postoperative laboratory MELD higher than 31 was 21.4%, while patients with a postoperative laboratory MELD lower than 31 displayed 30‐days and 12‐months survival rates of 80% and 71.8%, respectively (P < 0.001). Retransplantation in the setting of ELGI after OLT should be based on all available data. Utilization of the postoperative labMELD enables the transplant physician within 24 h after transplantation to identify necessity of retransplantation objectively.  相似文献   
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30.

Introduction

The target of this study was the development of a magnetic resonance imaging (MRI) compatible breast phantom for focused ultrasound which includes plastic (ABS) ribs. The objective of the current study was the evaluation of a focused ultrasound procedure using the proposed phantom that eliminates rib heating.

Material and Methods

The proposed phantom was evaluated using two different focused ultrasound exposures. The surrounding breast tissue was mimicked using an agar–silica–evaporation milk gel (2% w/v – 2% w/v – 40% v/v).

Results

The attenuation of the ABS was similar to that of ribs. MR thermometry of focused ultrasound exposures were acquired using the breast/rib phantom. In one exposure focused ultrasound was applied with far‐field targeting of the ribs. In the other exposure, the transducer was positioned laterally, thus avoiding exposure of the rib to focused ultrasound.

Conclusions

Due to growing interest in using MRI guided focused ultrasound (MRgFUS) for patients with breast cancer, the proposed breast/rib phantom can be utilized as a very useful tool for evaluating ultrasonic protocols.  相似文献   
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