[Advances in the use of neuromuscular electrical stimulation in the prevention of venous thromboembolism]

Pharmacologic prophylaxis is the most commonly used prophylaxis for venous thromboembolism (VTE), but the pharmacologic prophylaxis is limited in patients at high risk of bleeding. Mechanical prophylaxis alone or in combination is an important method of VTE prophylaxis in patients at high risk of bleeding, but the current mainstream mechanical prophylaxis, which includes graded compression stockings, intermittent inflatable compression pumps and plantar venous compression pumps, has some limitations, leading to discomfort for patients wearing them due to the large contact area, and even affecting ability to perform daily activities. Many clinical studies have found that NMES combined with pharmacological prophylaxis has better efficacy and safety than pharmacological prophylaxis alone in preventing VTE in medical and surgical patients, and the preventive effect of NMES alone is not inferior to other mechanical prophylaxis. Besides, it also has the advantages of ease of wear and patient compliance. Currently, clinicians have limited experience and knowledge of NMES. We aimed to present the rationale, progress in clinical research and future perspective of NMES in VTE prophylaxis.

Development and Validation of a Deep Learning Model to Reduce the Interference of Rectal Artifacts in MRI-based Prostate Cancer Diagnosis

Purpose To develop an MRI-based model for clinically significant prostate cancer (csPCa) diagnosis that can resist rectal artifact interference. Materials and Methods This retrospective study included 2203 male patients with prostate lesions who underwent biparametric MRI and biopsy between January 2019 and June 2023. Targeted adversarial training with proprietary adversarial samples (TPAS) strategy was proposed to enhance model resistance against rectal artifacts. The automated csPCa diagnostic models trained with and without TPAS were compared using multicenter validation datasets. The impact of rectal artifacts on the diagnostic performance of each model at the patient and lesion levels was compared using the area under the receiver operating characteristic curve (AUC) and the area under the precision-recall curve (AUPRC). The AUC between models was compared using the DeLong test, and the AUPRC was compared using the bootstrap method. Results The TPAS model exhibited diagnostic performance improvements of 6% at the patient level (AUC: 0.87 vs 0.81, P < .001) and 7% at the lesion level (AUPRC: 0.84 vs 0.77, P = .007) compared with the control model. The TPAS model demonstrated less performance decline in the presence of rectal artifact-pattern adversarial noise than the control model (ΔAUC: -17% vs -19%, ΔAUPRC: -18% vs -21%). The TPAS model performed better than the control model in patients with moderate (AUC: 0.79 vs 0.73, AUPRC: 0.68 vs 0.61) and severe (AUC: 0.75 vs 0.57, AUPRC: 0.69 vs 0.59) artifacts. Conclusion This study demonstrates that the TPAS model can reduce rectal artifact interference in MRI-based csPCa diagnosis, thereby improving its performance in clinical applications. Keywords: MR-Diffusion-weighted Imaging, Urinary, Prostate, Comparative Studies, Diagnosis, Transfer Learning Clinical trial registration no. ChiCTR23000069832 Supplemental material is available for this article. Published under a CC BY 4.0 license.

Electroacupuncture Stimulation Alleviates Inflammatory Pain in Male Rats by Suppressing Oxidative Stress

In the present study, we focused on whether the analgesic effect of Electroacupuncture (EA) is related to the regulation of oxidative stress. We established a chronic inflammatory pain model in male rats by a single injection of complete Freund's adjuvant (CFA) and then treated the animals with daily EA stimulation at the site of "zusanli". The analgesic effect of EA was evaluated by measuring the paw withdrawal threshold (PWT) when rats received mechanical and thermal pain stimulation. The levels of inflammation-related molecules and oxidative stress-related markers in the spinal cord were measured by western blotting or ELISA kits. EA stimulation and antioxidants effectively increased the PWT in CFA rats. Co-treatment of CFA rats with the ROS donor t-butyl hydroperoxide (t-BOOH) further decreased the PWT and weakened the analgesic effect of EA. EA treatment inhibited inflammation and oxidative stress, as shown by decreased levels of tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), IL-6, and MDA and increased activity of SOD and catalase. Moreover, EA reduced the expression of p-p38, p-ERK, and p-p65 and simultaneously downregulated the expression of TRPV1 and TRPV4 in CFA rats. In an in vitro study, direct stimulation with t-BOOH to the C6 cells increased the production of TNF-alpha, IL-1beta, IL-6, activated p38, ERK, and p65 and up-regulated the expression of TRPV1 and TRPV4, and these effects could be prevented by the ROS scavenger PBN. Taken together, our data indicate that the inhibition of oxidative stress and the generation of ROS contribute to the analgesic effect of EA in male CFA rats.

Iron homeostasis imbalance and ferroptosis in brain diseases

Brain iron homeostasis is maintained through the normal function of blood-brain barrier and iron regulation at the systemic and cellular levels, which is fundamental to normal brain function. Excess iron can catalyze the generation of free radicals through Fenton reactions due to its dual redox state, thus causing oxidative stress. Numerous evidence has indicated brain diseases, especially stroke and neurodegenerative diseases, are closely related to the mechanism of iron homeostasis imbalance in the brain. For one thing, brain diseases promote brain iron accumulation. For another, iron accumulation amplifies damage to the nervous system and exacerbates patients' outcomes. In addition, iron accumulation triggers ferroptosis, a newly discovered iron-dependent type of programmed cell death, which is closely related to neurodegeneration and has received wide attention in recent years. In this context, we outline the mechanism of a normal brain iron metabolism and focus on the current mechanism of the iron homeostasis imbalance in stroke, Alzheimer's disease, and Parkinson's disease. Meanwhile, we also discuss the mechanism of ferroptosis and simultaneously enumerate the newly discovered drugs for iron chelators and ferroptosis inhibitors.

[Recognition of abnormal changes in echocardiographic videos by an artificial intelligence assisted diagnosis model based on 3D CNN]

Objective: To investigate the diagnostic efficiency and clinical application value of an artificial intelligence-assisted diagnosis model based on a three-dimensional convolutional neural network (3D CNN) on echocardiographic videos of patients with hypertensive heart disease, chronic renal failure (CRF) and hypothyroidism with cardiac involvement. Methods: This study is a retrospective study. The patients with hypertensive heart disease, CRF and hypothyroidism with cardiac involvement, who admitted in Henan Provincial People's Hospital from April 2019 to October 2021, were enrolled. Patients were divided into hypertension group, CRF group, and hypothyroidism group. Additionally, a simple random sampling method was used to select control healthy individuals, who underwent physical examination at the same period. The echocardiographic video data of enrolled participants were analyzed. The video data in each group was divided into a training set and an independent testing set in a ratio of 5 to 1. The temporal and spatial characteristics of videos were extracted using an inflated 3D convolutional network (I3D). The artificial intelligence assisted diagnosis model was trained and tested. There was no case overlapped between the training and validation sets. A model was established according to cases or videos based on video data from 3 different views (single apical four chamber (A4C) view, single parasternal left ventricular long-axis (PLAX) view and all views). The statistical analysis of diagnostic performance was completed to calculate sensitivity, specificity and area under the ROC curve (AUC). The time required for the artificial intelligence and ultrasound physicians to process cases was compared. Results: A total of 730 subjects aged (41.9±12.7) years were enrolled, including 362 males (49.6%), and 17 703 videos were collected. There were 212 cases in the hypertensive group, 210 cases in the CRF group, 105 cases in the hypothyroidism group, and 203 cases in the normal control group. The diagnostic performance of the model predicted by cases based on single PLAX view and all views data was excellent: (1) in the hypertensive group, the sensitivity, specificity and AUC of models based on all views data were 97%, 89% and 0.93, respectively, while those of models based on a single PLAX view were 94%, 95%, and 0.94, respectively; (2) in the CRF group, the sensitivity, specificity and AUC of models based on all views data were 97%, 95% and 0.96, respectively, while those of models based on a single PLAX view were 97%, 89%, and 0.93, respectively; (3) in the hypothyroidism group, the sensitivity, specificity and AUC of models based on all views data were 64%, 100% and 0.82, respectively, while those of models based on a single PLAX view were 82%, 89%, and 0.86, respectively. The time required for the 3D CNN model to measure and analyze the echocardiographic videos of each subject was significantly shorter than that for the ultrasound physicians ((23.96±6.65)s vs. (958.25±266.17)s, P<0.001). Conclusions: The artificial intelligence assisted diagnosis model based on 3D CNN can extract the dynamic temporal and spatial characteristics of echocardiographic videos jointly, and quickly and efficiently identify hypertensive heart disease and cardiac changes caused by CRF and hypothyroidism.

Automated deep-learning system in the assessment of MRI-visible prostate cancer: comparison of advanced zoomed diffusion-weighted imaging and conventional technique

BACKGROUND

Deep-learning-based computer-aided diagnosis (DL-CAD) systems using MRI for prostate cancer (PCa) detection have demonstrated good performance. Nevertheless, DL-CAD systems are vulnerable to high heterogeneities in DWI, which can interfere with DL-CAD assessments and impair performance. This study aims to compare PCa detection of DL-CAD between zoomed-field-of-view echo-planar DWI (z-DWI) and full-field-of-view DWI (f-DWI) and find the risk factors affecting DL-CAD diagnostic efficiency.

METHODS

This retrospective study enrolled 354 consecutive participants who underwent MRI including T2WI, f-DWI, and z-DWI because of clinically suspected PCa. A DL-CAD was used to compare the performance of f-DWI and z-DWI both on a patient level and lesion level. We used the area under the curve (AUC) of receiver operating characteristics analysis and alternative free-response receiver operating characteristics analysis to compare the performances of DL-CAD using f- DWI and z-DWI. The risk factors affecting the DL-CAD were analyzed using logistic regression analyses. P values less than 0.05 were considered statistically significant.

RESULTS

DL-CAD with z-DWI had a significantly better overall accuracy than that with f-DWI both on patient level and lesion level (AUC_patient: 0.89 vs. 0.86; AUC_lesion: 0.86 vs. 0.76; P < .001). The contrast-to-noise ratio (CNR) of lesions in DWI was an independent risk factor of false positives (odds ratio [OR] = 1.12; P < .001). Rectal susceptibility artifacts, lesion diameter, and apparent diffusion coefficients (ADC) were independent risk factors of both false positives (OR_{rectal susceptibility artifact} = 5.46; OR_diameter, = 1.12; OR_ADC = 0.998; all P < .001) and false negatives (OR_{rectal susceptibility artifact} = 3.31; OR_diameter = 0.82; OR_ADC = 1.007; all P ≤ .03) of DL-CAD.

CONCLUSIONS

Z-DWI has potential to improve the detection performance of a prostate MRI based DL-CAD.

TRIAL REGISTRATION

ChiCTR, NO. ChiCTR2100041834 . Registered 7 January 2021.

[Influencing factors of iron metabolism assessment in patients with myelodysplastic syndrome: A retrospective study]

Objective: To analyze the influencing factors of iron metabolism assessment in patients with myelodysplastic syndrome. Methods: MRI and/or DECT were used to detect liver and cardiac iron content in 181 patients with MDS, among whom, 41 received regular iron chelation therapy during two examinations. The adjusted ferritin (ASF) , erythropoietin (EPO) , cardiac function, liver transaminase, hepatitis antibody, and peripheral blood T cell polarization were detected and the results of myelofibrosis, splenomegaly, and cyclosporine were collected and comparative analyzed in patients. Results: We observed a positive correlation between liver iron concentration and ASF both in the MRI group and DECT groups (r=0.512 and 0.606, respectively, P<0.001) , only a weak correlation between the heart iron concentration and ASF in the MRI group (r=0.303, P<0.001) , and no significant correlation between cardiac iron concentration and ASF in the DECT group (r=0.231, P=0.053) . Moreover, transfusion dependence in liver and cardiac [MRI group was significantly associated with the concentration of iron in: LIC: (28.370±10.706) mg/g vs (7.593±3.508) mg/g, t=24.30, P<0.001; MIC: 1.81 vs 0.95, z=2.625, P<0.05; DECT group: liver VIC: (4.269±1.258) g/L vs (1.078±0.383) g/L, t=23.14, P<0.001: cardiac VIC: 1.69 vs 0.68, z=3.142, P<0.05]. The concentration of EPO in the severe iron overload group was significantly higher than that in the mild to moderate iron overload group and normal group (P<0.001) . Compared to the low-risk MDS group, the liver iron concentration in patients with MDS with cyclic sideroblasts (MDS-RS) was significantly elevated [DECT group: 3.80 (1.97, 5.51) g/L vs 1.66 (0.67, 2.94) g/L, P=0.004; MRI group: 13.7 (8.1,29.1) mg/g vs 11.6 (7.1,21.1) mg/g, P=0.032]. Factors including age, bone marrow fibrosis, splenomegaly, T cell polarization, use of cyclosporine A, liver aminotransferase, and hepatitis antibody positive had no obvious effect on iron metabolism. Conclusion: There was a positive correlation between liver iron concentration and ASF in patients with MDS, whereas there was no significant correlation between cardiac iron concentration and ASF. Iron metabolism was affected by transfusion dependence, EPO concentration, and RS.

Better lesion conspicuity translates into improved prostate cancer detection: comparison of non-parallel-transmission-zoomed-DWI with conventional-DWI

PURPOSE

To compare advanced non-parallel transmission zoomed diffusion-weighted imaging (nonPTX zoom-DWI) to conventional DWI (conv-DWI) for the assessment of prostate cancer (PCa).

METHODS

This retrospective study included 98 patients who underwent conv-DWI, nonPTX zoom-DWI, and T2-weighted imaging of the prostate. The image qualities of the two DWI sets, including the distortion of the prostate and the existence of artifacts, were evaluated. To compare the overall PCa and clinically important PCa (ciPCa) detection ability between the sets, lesions were scored using the Prostate Imaging Reporting and Data System (PI-RADS) version 2. Apparent diffusion coefficient (ADC) values of the lesions were also measured and compared. The Mann-Whitney U test was used to compare continuous variables, and the χ² test was used to compare categorical variables. Two-sided P values of < 0.05 were considered significant.

RESULTS

Non-PTX zoom-DWI yielded significantly better image quality and image analysis reproducibility than conv-DWI (all P < 0.001). Compared with conv-ADC, nonPTX zoom-ADC showed slightly better detection performance for overall PCa (AUC: 0.827 vs. 0.797; P = 0.55) and ciPCa (AUC: 0.822 vs. 0.749; P = 0.58). At a PI-RADS score of 4 as the cutoff value for PCa prediction, nonPTX zoom-DWI showed significantly higher diagnostic efficiency for overall PCa detection (sensitivity: 87.9% vs. 72.4%; specificity: 87.5% vs. 77.5%; both P < 0.05) and ciPCa detection (sensitivity: 86.3% vs. 74.5%; specificity: 72.3% vs. 63.8%; both P ≤ 0.001).

CONCLUSION

Non-PTX zoom-DWI yields better image quality and higher PCa detection performance than Conv-DWI.

Upregulating CXCR7 accelerates endothelial progenitor cell-mediated endothelial repair by activating Akt/Keap-1/Nrf2 signaling in diabetes mellitus

Background

Endothelial progenitor cell (EPC) dysfunction contributes to vascular disease in diabetes mellitus. However, the molecular mechanism underlying EPC dysfunction and its contribution to delayed reendothelialization in diabetes mellitus remain unclear. Our study aimed to illustrate the potential molecular mechanism underlying diabetic EPC dysfunction in vivo and in vitro. Furthermore, we assessed the effect of EPC transplantation on endothelial regeneration in diabetic rats.

Methods

Late outgrowth EPCs were isolated from the bone marrow of rats for in vivo and in vitro studies. In vitro functional assays and Western blotting were conducted to reveal the association between C-X-C chemokine receptor type 7 (CXCR7) expression and diabetic EPC dysfunction. To confirm the association between cellular CXCR7 levels and EPC function, CXCR7 expression in EPCs was upregulated and downregulated via lentiviral transduction and RNA interference, respectively. Western blotting was used to reveal the potential molecular mechanism by which the Stromal-Derived Factor-1 (SDF-1)/CXCR7 axis regulates EPC function. To elucidate the role of the SDF-1/CXCR7 axis in EPC-mediated endothelial regeneration, a carotid artery injury model was established in diabetic rats. After the model was established, saline-treated, diabetic, normal, or CXCR7-primed EPCs were injected via the tail vein.

Results

Diabetic EPC dysfunction was associated with decreased CXCR7 expression. Furthermore, EPC dysfunction was mimicked by knockdown of CXCR7 in normal EPCs. However, upregulating CXCR7 expression reversed the dysfunction of diabetic EPCs. The SDF-1/CXCR7 axis positively regulated EPC function by activating the AKT-associated Kelch-like ECH-associated protein 1 (keap-1)/nuclear factor erythroid 2-related factor 2 (Nrf2) axis, which was reversed by blockade of AKT and Nrf2. Transplantation of CXCR7-EPCs accelerated endothelial repair and attenuated neointimal hyperplasia in diabetes mellitus more significantly than transplantation of diabetic or normal EPCs. However, the therapeutic effect of CXCR7-EPC transplantation on endothelial regeneration was reversed by knockdown of Nrf2 expression.

Conclusions

Dysfunction of diabetic EPCs is associated with decreased CXCR7 expression. Furthermore, the SDF-1/CXCR7 axis positively regulates EPC function by activating the AKT/keap-1/Nrf2 axis. CXCR7-primed EPCs might be useful for endothelial regeneration in diabetes-associated vascular disease.

CGM for insulinoma screening: a prospective and observational case-control study

Insulin release index (IRI) based on 72-h fasting test has been used for the definitive diagnosis of insulinoma; however, hospitalization and subsequent costs contribute to the disadvantage of IRI. Therefore, a simple and cost-effective screening procedure for the diagnosis of insulinoma for outpatients are crucially needed. Continuous glucose monitoring (CGM) has been widely used for monitoring high level of glucose in diabetic patients. The aim of the study is to determine the potential contribution or implementation of CGM in the screening of the insulinoma. We performed a single-center prospective study with the demographics and laboratory data including 28 patients with the pathological diagnosis of insulinoma and 25 patients with functional hypoglycemia as control group. The analysis showed that areas under the receiver operating characteristic (ROC) curve of coefficient of variation (CV) was 0.914. The CV cutoff point was 19% with the Youden 62.1%, the corresponding sensitivity and specificity were 82.1 and 80%, respectively. In patients with CV greater than the median, more than 60% of insulinomas were located in the head of the pancreas; most Ki-67 values were more than 2% and when compared with the group with CV smaller than the median, the average tumor size was 2.7 times larger. In conclusion, CGM can be used as a valuable tool in not only monitoring high glucose levels in diabetic patients but also identifying the etiology of insulinoma. CV greater than 19% can be highly effective for the screening of insulinoma in outpatients.

Plerixafor stimulates adhesive activity and endothelial regeneration of endothelial progenitor cells via elevating CXCR7 expression

AIMS

To assess the effects of plerixafor on function and endothelial regeneration of endothelial progenitor cells (EPCs).

METHODS

The proliferation and adhesion capacity of EPCs were evaluated in vitro. Furthermore, the expression levels of CXC chemokine receptor-7 (CXCR7) were detected before and after treatment with plerixafor. The CXCR7 expression of EPCs was knocked-down by RNA interference to evaluate the role of CXCR7 in regulating function of EPCs. A rat carotid artery injury model was established to assess the influences of plerixafor on endothelial regeneration.

RESULTS

Plerixafor stimulated adhesion capacity of EPCs, associating with upregulation of CXCR7 and activation of LFA-1 and VLA-4 molecules. Knockdown of CXCR7 slightly impaired proliferation capacity but significantly attenuated adhesion capacity of EPCs. Plerixafor facilitated endothelial repair at 7 days, while reduced neointimal hyperplasia at 7 and 14 days via recruiting more EPCs participating in endothelial reparation.

CONCLUSIONS

Plerixafor can positively regulate adhesion capacity of EPCs to HUVECs via elevating the expression level of CXCR7 and stimulating LFA-1 and VLA-4 molecules activation. Treatment with plerixafor accelerated re-endothelialization and inhibited neointimal hyperplasia after endoth elial injury, indicating that it can to be used for endothelial regeneration.

AMD3100 and SDF‑1 regulate cellular functions of endothelial progenitor cells and accelerate endothelial regeneration in a rat carotid artery injury model

The present study was conducted to assess the effects of AMD3100 and stromal cell-derived factor 1 (SDF-1) on cellular functions and endothelial regeneration of endothelial progenitor cells (EPCs). The cell proliferation and adhesion capacity of EPCs were evaluated in vitro following treatment with AMD3100 and SDF-1 using a Cell Counting Kit-8 assay. Furthermore, the expression levels of C-X-C motif chemokine receptor 4 (CXCR4) and C-X-C motif chemokine receptor 7 (CXCR7) were detected before and after treatment with AMD3100 and SDF-1 to elucidate their possible role in regulating the cellular function of EPCs. A rat carotid artery injury model was established to assess the influences of AMD3100 and SDF-1 on endothelial regeneration. AMD3100 reduced the proliferation and adhesion capacity of EPCs to fibronectin (FN), whereas it increased the adhesion capacity of EPCs to human umbilical vein endothelial cells (HUVECs). However, SDF-1 stimulated the proliferation and cell adhesion capacity of EPCs to HUVECs and FN. Additionally, the expression levels of CXCR7 but not CXCR4 were upregulated following AMD3100 treatment, whereas the expression levels of both CXCR4 and CXCR7 were upregulated after SDF-1 treatment. In vivo results demonstrated that AMD3100 increased the number of EPCs in the peripheral blood and facilitated endothelial repair at 7 days after treatment. However, local administration of SDF-1 alone did not enhance reendothelialization 7 and 14 days after treatment. Importantly, the combination of AMD3100 with SDF-1 exhibited superior therapeutic effects compared with AMD3100 treatment alone, accelerated reendothelialization 7 days after treatment, and attenuated neointimal hyperplasia at day 7 and 14 by recruiting more EPCs to the injury site. In conclusion, AMD3100 could positively regulate the adhesion capacity of EPCs to HUVECs via elevation of the expression levels of CXCR7 but not CXCR4, whereas SDF-1 could stimulate the proliferation and adhesion capacity of EPCs to FN and HUVECs by elevating the expression levels of CXCR4 and CXCR7. AMD3100 combined with SDF-1 outperformed AMD3100 alone, promoted early reendothelialization and inhibited neointimal hyperplasia, indicating that early reendothelialization attenuated neointimal hypoplasia following endothelial injury.

Index of Plantar Pressure Alters with Prolonged Diabetes Duration

INTRODUCTION

Diabetic foot ulcers develop with deviations in the distribution of plantar pressure. It is difficult to interpret any alteration in plantar pressure under different conditions of type 2 diabetes mellitus (T2DM). The aim of this study was to gain a better insight into the variations in plantar pressure with increased duration of diabetes.

METHODS

Plantar pressure was examined in 1196 participants with or without T2DM. Subjects with normal glucose tolerance (NGT) and impaired glucose tolerance (IGT) were assigned to control groups, and those with T2DM were divided into five groups according to diabetes duration (< 2 years, 2-5 years, 5-10 years, 10-15 years, and > 15 years). The clinical characteristics, plantar peak pressure, and pressure-time integral (PTI) were compared among the seven study groups, and factors associated with peak pressure and the PTI were analyzed.

RESULTS

At the hallux, peak pressure exhibited an upward trend in patients with T2DM within 5 years of diabetes duration, followed by a distinct downward slope with further progression of the disease (trend analysis, p  < 0.05). An uneven distribution of peak pressure was found at other locations, but this unevenness was ultimately lower than that in the two control groups (p  < 0.05). No obvious trend was noted for PTI among patients with different diabetes duration; however, those with diabetes for > 10 years manifested a significantly sharper increase in the PTI at the metatarsus (11.63 Ns/cm², p  < 0.05) and heel (14.12 Ns/cm², p  < 0.05) than at the hallux (8.76 Ns/cm²). A fluctuation in the PTI was also detected at the hallux and midfoot of diabetes patients, which was broadly flat when compared with that of the two control groups. The stepwise multiple regression analysis revealed that the variation in plantar pressure was independently associated with age, body mass index, and vibration perception threshold (VPT) (p  < 0.05).

CONCLUSIONS

There would appear to be an association between longer diabetes duration and decreased peak pressure for the hallux, suggesting that individuals with diabetes for > 10 years will have an increased PTI for the metatarsus and heel. The reduced pressure on the hallux is believed to be transferred to the metatarsus. Age, BMI, and VPT are distinct risk factors of abnormal plantar pressure.

Comparison of endothelial cell- and endothelial progenitor cell-derived exosomes in promoting vascular endothelial cell repair

BACKGROUND

Timely endothelial repair after intervention-associated vascular injury is critical to prevent restenosis and thrombosis. Compared to living cell therapies, exosomes may be a better alternative. Thus, we aimed to compare the role of exosomes derived from human umbilical vein endothelial cells (HUVECs) versus those derived from endothelial progenitor cells (EPCs) in vascular endothelial repair.

MATERIAL/METHODS

Exosomes secreted from HUVECs and EPCs were isolated and characterized respectively. In vitro, the effects of the two types of exosomes on migration and proliferation of endothelial cells were studied. In vivo, rats were systemically treated with the two exosome groups respectively after carotid artery endothelial injury induced by a balloon. The efficacy in promoting re-endothelialization was measured by Evans blue dye and histological examination.

RESULTS

Both types of exosomes, sized from 30 nm to 100 nm, had sphere-shaped or cupped morphology, and expressed CD63, CD9, and CD81; but the total yield of exosomes (particles/mL) based on number of cells, was 4.2 times higher from EPCs than HUVECs. Compared with control treatment, both exosome treated groups manifested significant enhancement of migration and proliferation in vitro and vascular recovery at an early stage in vivo. The two exosome-treated groups, however, did not statistically significantly differ.

CONCLUSION

In conclusion, our results indicated that exosomes derived from HUVECs and EPCs had similar morphology, size distributions and characteristics, but those derived from EPCs were more abundant with comparable biologic activity. Therefore, EPCs may be a robust source of exosomes to promote vascular repair.

[The subgroup analysis of the prognostic value of the intraductal carcinoma of the prostate in patients with metastatic prostate cancer]

Objective: To determine the prognostic value of the intraductal carcinoma of the prostate IDC-P in metastatic prostate cancer (mPCa) patients of different subgroups. Methods: Data of 582 de novo mPCa patients between January 2011 and December 2017 diagnosed at Departments of Urology, West China Hospital, Sichuan University were retrospectively analyzed. The age was (70±8) years (range: 45 to 89 years). IDC-P was identified from 12-core prostate biopsy. The prognostic role of IDC-P was assessed by Kaplan-Meier curves and Cox regression. Subgroup analysis was conducted by the forest plot. The endpoints were castration-resistant prostate cancer free survival (CFS) and overall survival (OS). Results: In total, 177/582 (30.4%) patients harbored IDC-P. Patients with IDC-P had poorer CFS and OS than those without IDC-P (mCFS: 12.1 months vs. 16.9 months, P=0.000; mOS: 39.7 months vs. not reached, P=0.000). Multivariate Cox regression analysis indicated that, the existence of IDC-P was an independent prognosticator of both CFS (HR=1.40, 95% CI: 1.10 to 1.79, P=0.006) and OS (HR=1.51, 95% CI: 1.02 to 2.25, P=0.041). Subanalysis indicated that, in most subgroups, IDC-P was an adverse prognosticator of both CFS and OS. Even in subgroups with adverse clinicopathological features, e.g. Gleason score 9 to 10 (CFS: HR=1.467, P=0.007; OS: HR=1.807, P=0.013), baseline prostate specific antigen≥50 μg/L (CFS: HR=1.616, P=0.000; OS: HR=1.749, P=0.006), anemia (CFS: HR=1.653, P=0.036; OS: HR=2.100, P=0.038), alkaline phosphatase≥160 U/L (CFS: HR=1.326, P=0.038; OS: HR=1.725, P=0.010) or abnormal lactate dehydrogenase level (CFS: HR=1.614, P=0.001; OS: HR=1.900, P=0.003), IDC-P was still closely associated with shorter CFS and OS. Conclusions: The presence of IDC-P was closely related to poor survival outcomes for patients with mPCa. IDC-P was an adverse prognosticator in most subgroup patients. The description of IDC-P in the pathological report of prostate biopsy would help clinicians to evaluate the prognosis of mPCa patients more accurately and make better treatment choices.

The value of ankle-branchial index screening for cardiovascular disease in type 2 diabetes

OBJECTIVE

To investigate the relationship between ankle-branchial index (ABI) and cardiovascular disease in type 2 diabetes patients.

METHODS

A total of 634 inpatients with type 2 diabetes were recruited in this cross-sectional study. All patients were measured with ABI and computed tomography angiography (CTA) scan for coronary artery disease (CAD). According to ABI values, patients were divided into three groups: low-ABI group (ABI < 0.9, n = 259), normal-ABI group (ABI = 0.9-1.3, n = 272), and high-ABI group (ABI > 1.3, n = 103). According to the manifestation of coronary CTA, the patients were divided into CAD group (n = 348) and non-CAD group (n = 286). Their clinical data and biochemical parameters were compared and analysed.

RESULTS

The prevalence of CAD in low-ABI group (90%) was significantly higher than that of normal-ABI group (33%) and high-ABI group (25%) (both P < 0.01). Spearman correlation analysis showed that age, sex, duration, spontaneous bacterial peritonitis, total cholesterol (TC), triglyceride, low-density lipoprotein cholesterol (LDL-C), serum creatinine, and glycosylated haemoglobin (HbA_1c ) were positively correlated with CAD, and high-density lipoprotein cholesterol (HDL-C), glomerular filtration rate, and ABI were negatively correlated with CAD. Logistic regression analysis further revealed that age, sex, duration, TC, HDL-C, LDL-C, HbA_1c , and ABI were independent risk factors of CAD. After all potential confounders is adjusted, the risk of CAD in low-ABI group still increased over four times than the normal-ABI group (odds ratio [OR], 5.32; 95% CI, 1.973-16.5; P < 0.001). In female patients, this risk increased more than nine times (OR, 10.63; 95% CI, 3.416-17.8; P < 0.001). Receiver-operating characteristic analysis indicated that ABI < 1.045 predicted the occurrence of CAD (sensitivity, 79.7%; specificity, 71.5%; P < 0.01).

CONCLUSIONS

ABI is an independent risk factor for CAD and may be a potential simple screening instrument for CAD in Chinese type 2 diabetic patients, especially in elder women.

Vitamin D deficiency increases the risk of peripheral neuropathy in Chinese patients with type 2 diabetes

BACKGROUND

Vitamin D deficiency was reported to be associated with diabetic peripheral neuropathy. But the association in Chinese population and the screening value of vitamin D deficiency for diabetic peripheral neuropathy were unknown.

METHODS

A total of 861 patients with type 2 diabetes were recruited in this cross-sectional study. Vitamin D deficiency was defined as serum circulating 25-hydroxyvitamin D(25(OH)D) level < 20 ng/mL. Peripheral neuropathy was evaluated by neurological symptoms, neurological signs, neurothesiometer and electromyogram.

RESULTS

The patients with diabetic peripheral neuropathy had significantly lower serum 25(OH)D concentration (15.59 ± 7.68 ng/mL) and higher prevalence of vitamin D deficiency (80%) than patients with signs of diabetic peripheral neuropathy (17.66 ± 7.50 ng/mL; 64.5%) and non-DPN patients (18.35 ± 6.60; 61.7%) (all p < 0.01). Spearman's correlation analysis showed that serum circulating 25(OH)D level was closely associated with DPN (r = 0.121) and signs of DPN (r = 0.111) (both p < 0.01). After adjusting for all potential confounders, VDD was still linked with increased risk of DPN [odds ratio 2.59 (1.48-4.53)] (p < 0.01). Logistical regression analysis further revealed that VDD was an independent risk factor for DPN (β = 0.88) (p < 0.01). Receiver operating characteristic analysis indicated that serum 25(OH)D < 17.22 ng/mL hinted the signs of DPN and serum 25(OH)D < 16.01 ng/mL predicted the occurrence of DPN (both p < 0.01).

CONCLUSIONS

Vitamin D deficiency is an independent risk factor for diabetic peripheral neuropathy and may be a potential biomarker for peripheral neuropathy in Chinese patients with type 2 diabetes. Copyright © 2016 John Wiley & Sons, Ltd.

[Value of MRI in prenatal diagnosis of abnormal fetal kidneys]

Objective: To investigate the value of MRI in the prenatal diagnosis of abnormal fetal kidneys. Methods: From December 2014 to March 2016, 51 women underwent MRI and were confirmed as having fetuses with abnormal fetal kidneys when follow up. Their clinical and MRI profiles were analyzed retrospectively, including MRI manifestation, the fetal kidney signal intensity of diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC). The signal intensity of DWI and ADC of the abnormal kidney and the normal opposite kidney, and those of the normal and abnormal kidneys in different individuals were compared. The accuracies of MRI and ultrasound in evaluating abnormal fetal kidneys were also compared. Results: MRI could accurately demonstrate the morphological features of abnormal fetal kidneys. There was no statistically significant difference between DWI signal intensity and ADC value of the abnormal kidney[368 ± 125, (1.516 ± 0.420) × 10^-3 mm²/s] and the normal opposite one[410 ± 125, (1.362 ± 0.251) × 10^-3 mm²/s], P values were 0.165 and 0.184, respectively. The DWI signal intensity of normal kidneys (401 ± 124) was higher than that of renal cysts (182 ± 40, P <0.01), and the ADC value of normal kidneys[(1.306 ± 0.252) × 10^-3 mm²/s] was lower than that of renal cysts[(2.912 ± 0.235) × 10^-3 mm²/s] and multicystic dysplastic kidneys[(1.870±0.654) ×10^-3 mm²/s], P values were <0.01 and 0.045, respectively. The diagnostic accuracy of MRI and prenatal ultrasound for abnormal fetal kidneys were 94% (63/67) and 85% (57/67), respectively. However, there was no statistical difference between the two methods (P=0.070). Conclusion: MRI have an important role in the prenatal diagnosis and evaluation of abnormal fetal kidneys.

Pancreatic volume is reduced in patients with latent autoimmune diabetes in adults

AIMS

This study aimed to compare pancreatic volume and its clinical significance among patients with type 2 diabetes mellitus (DM), adult-onset type 1 DM and latent autoimmune diabetes in adults (LADA).

METHODS

This is a cross-sectional study. One hundred twenty-six outpatients (68 with LADA and 58 with type 1 DM) and 158 inpatients (71 with type 2 DM and 87 non-diabetic controls) were recruited during May-July 2013 in Shanghai Jiao Tong University Affiliated Sixth People's Hospital. All the patients underwent abdominal computerized tomography; pancreatic volume was then calculated.

RESULTS

The mean pancreatic volume was highest in the controls, followed by those in patients with type 2 DM, LADA and type 1 DM. The pancreatic volume in LADA was comparable with that in type 2 DM but significantly greater than that in type 1 DM (p < 0.05). The pancreatic volume in patients with LADA was significantly correlated with sex, waist circumference, body surface area, body mass index, diastolic blood pressure and high-density lipoprotein cholesterol (all p < 0.05). The correlation between pancreatic volume and fasting C-peptide was high in patients with LADA (r = 0.643, p < 0.001) and moderate in patients with type 2 DM (r = 0.467, p < 0.001). The area under the receiver operating characteristic curve for pancreatic volume predictive of absolute insulin deficiency (FCP < 0.9 ng/mL) was 0.85 (0.76-0.94) in LADA.

CONCLUSIONS

Pancreatic atrophy in LADA was less marked than in type 1 DM. Pancreatic atrophy may suggest reduced level of fasting C-peptide in patients with LADA. Copyright © 2016 John Wiley & Sons, Ltd.

Exosomes derived from endothelial progenitor cells attenuate vascular repair and accelerate reendothelialization by enhancing endothelial function

BACKGROUND AIMS

Exosomes, a key component of cell paracrine secretion, can exert protective effects in various disease models. However, application of exosomes in vascular repair and regeneration has rarely been reported. In this study, we tested whether endothelial progenitor cell (EPC)-derived exosomes possessed therapeutic effects in rat models of balloon-induced vascular injury by accelerating reendothelialization.

METHODS

Exosomes were obtained from the conditioned media of EPCs isolated from human umbilical cord blood. Induction of the endothelial injury was performed in the rats' carotid artery, and the pro-re-endothelialization capacity of EPC-derived exosomes was measured. The in vitro effects of exosomes on the proliferation and migration of endothelial cells were investigated.

RESULTS

We found that the EPC-derived exosomes accelerated the re-endothelialization in the early phase after endothelial damage in the rat carotid artery. We also demonstrated that these exosomes enhanced the proliferation and migration of endothelial cells in vitro. Moreover, endothelial cells stimulated with these exosomes showed increased expression of angiogenesis-related molecules.

CONCLUSIONS

Taken together, our results indicate that exosomes are an active component of the paracrine secretion of human EPCs and can promote vascular repair in rat models of balloon injury by up-regulating endothelial cells function.

Human endothelial progenitor cells-derived exosomes accelerate cutaneous wound healing in diabetic rats by promoting endothelial function

AIMS

Wound healing is deeply dependent on neovascularization to restore blood flow. The neovascularization of endothelial progenitor cells (EPCs) through paracrine secretion has been reported in various tissue repair models. Exosomes, key components of cell paracrine mechanism, have been rarely reported in wound healing.

METHODS

Exosomes were isolated from the media of EPCs obtained from human umbilical cord blood. Diabetic rats wound model was established and treated with exosomes. The in vitro effects of exosomes on the proliferation, migration and angiogenic tubule formation of endothelial cells were investigated.

RESULTS

We revealed that human umbilical cord blood EPCs derived exosomes transplantation could accelerate cutaneous wound healing in diabetic rats. We also showed that exosomes enhanced the proliferation, migration and tube formation of vascular endothelial cells in vitro. Furthermore, we found that endothelial cells stimulated with these exosomes would increase expression of angiogenesis-related molecules, including FGF-1, VEGFA, VEGFR-2, ANG-1, E-selectin, CXCL-16, eNOS and IL-8.

CONCLUSION

Taken together, our findings indicated that EPCs-derived exosomes facilitate wound healing by positively modulating vascular endothelial cells function.

A high thyroid stimulating hormone level is associated with diabetic peripheral neuropathy in type 2 diabetes patients

AIM

The association between thyroid stimulating hormone (TSH) and type 2 diabetes mellitus (T2DM) is well known. However, whether TSH is related to diabetic peripheral neuropathy (DPN) has not been studied. The aim of this study was to explore the relationship between TSH and DPN in Chinese patients with T2DM.

METHODS

In this cross-sectional study, 605 patients with T2DM were enrolled. Subclinical hypothyroidism (SCH) was defined as an elevated TSH level (>4.0mIU/L) and a normal free thyroxine level. DPN was evaluated by neurological symptoms, neurological signs, and electromyogram.

RESULTS

Serum TSH levels were significantly higher in DPN and signs of DPN compared with non-DPN T2DM patients (both P<0.01).The prevalence of DPN and signs of DPN in SCH subjects was higher than that in euthyroid subjects (both P<0.01). Spearman's correlation analysis showed that the serum TSH level was positively associated with DPN (r=0.172, P<0.01). A significant independent association between TSH and DPN was found by multiple logistic regression analysis after adjusting for potential confounding variables [odds ratio (OR)=1.365, P<0.01]. The patients were sequentially assigned to quartiles according to TSH level. Compared with quartile 1, patients in quartile 2 (P<0.01), quartile 3 (P=0.01), and quartile 4 (P<0.01) had a higher risk of DPN. Receiver-operating characteristic curve analysis revealed that the optimal cutoff point of TSH to indicate DPN was 3.045mIU/L in men and 2.94mIU/L in women.

CONCLUSION

TSH level is independently associated with DPN in Chinese population with T2DM. A high serum TSH level may be a potential risk factor for DPN.

High cystatin C levels predict undesirable outcome for diabetic foot ulcerations

We investigated the relationship between serum cystatin C levels and the prognosis of diabetic foot ulcerations (DFU). A population-based cohort study involving 1018 patients with type 2 diabetes was conducted. These patients recruited and divided into two groups: nondiabetic foot ulcer group (NDF, n = 865, 85.5%) and diabetic foot ulcer group (DFU, n = 147, 14.5%).After a 1-year-follow-up, DFUs were grouped into healing (n = 110, 74.8%) and nonhealing (n = 37, 25.2%) group based on the clinical prognosis. Compared with the healing group, the nonhealing group were older, had long diabetic duration and had significantly increased serum cystatin C concentrations in DFU (p < 0.01). After adjustments for age, diabetes duration, renal function and infection control, multiple logistical regression analysis revealed that cystatin C remained associated increased risk of undesirable DFU outcome (OR = 7.279, 95% CI: 1.299-40.784, p < 0.05). When divided into quartiles according to cystatin C levels, the healing rate of Quartile 4 was significantly lower (57.9%) compared with other groups (p < 0.01). The odd is ratio (OR) analysis showed that the risk of undesirable DFU outcome in Quartile 4 was significantly higher (OR = 4.554, 95% CI: 3.14-5.12, p < 0.05) compared with that in Quartile 1. We concluded that there was a strong and independent association between serum cystatin C and diabetic foot ulceration prognosis, cystatin C > 1.35 mg/L predicts more than sixfold increased risk of incurable foot ulceration.

Serum fibroblast growth factor 21 levels is associated with lower extremity atherosclerotic disease in Chinese female diabetic patients

Background

Fibroblast growth factor 21 (FGF21) is an emerging metabolic regulator associated with glucose and lipid metabolism, and it is still unclear whether FGF21 is related to atherosclerosis. Here, we explored the potential link between FGF21 and lower extremity atherosclerotic disease (LEAD) in type 2 diabetic patients.

Methods

A cross-sectional study was conducted on 504 type 2 diabetic patients (283 men, 221 women). LEAD was defined by Ankle-brachial index (ABI) <0.9 and lower extremity arterial plaque evaluated by color Doppler ultrasound. Serum FGF21 concentrations were quantified by a sandwich enzyme-linked immunosorbent assay.

Results

The total FGF21 levels of male and female patients had no significant differenence ((299.14(177.31-534.49) vs 362.50(214.01-578.73), P=0.516). Serum FGF21 levels in LEAD group were significantly higher than non-LEAD group in females (385.34(243.89-661.54) vs 313.13(156.38-485.79), P=0.006), while not in male patients (295.52(177.09-549.64) vs 342.09 (198.70-549.87), P=0.613). In diabetic women, subjects with LEAD had significantly higher serum FGF21 regardless of non-alcoholic fatty liver disease (NAFLD) (P < 0.05). And serum FGF21 levels were positively correlated with waist circumference and systolic blood pressure after adjusted for age and BMI (r=0.198, P=0.004; r=0.152, P=0.027; respectively). Moreover, FGF21 was independently tied to femoral intima-media thickness (FIMT) (β=0.208, P=0.031). After adjusted for other LEAD risk factors, FGF21 was demonstrated to be an independent risk factor for LEAD in type 2 diabetic women (OR, 1.106; 95%CI 1.008-1.223; P=0.028). In addition, FGF21 was negatively correlated with estradiol in premenopausal diabetic women (r=−0.368, P=0.009). After adjusted for estradiol, serum FGF21 levels were still positively associated with FIMT in premenopausal diabetic women (r=0.381, P=0.007). In diabetic men, serum FGF21 levels were correlated with triglyceride and C-reactive protein even after adjusted for age and BMI (r=0.204, P=0.001; r=0.312, P < 0.001; respectively). However, serum FGF21 was not an independent impact factor for LEAD in men (P > 0.05).

Conclusions

Serum FGF21 level independently and positively links LEAD in Chinese women with type 2 diabetes. The gender difference may be due to different estrogen levels.

High Ankle-Brachial Index Indicates Cardiovascular and Peripheral Arterial Disease in Patients With Type 2 Diabetes

We assessed the association between high ankle-brachial index (ABI) and cardiovascular disease (CVD) and peripheral arterial disease (PAD) in Chinese patients with type 2 diabetes mellitus (T2DM). The ABI was measured, and foot inspection was performed in 2080 outpatients with T2DM. The clinical characters in different ABI levels were analyzed, and the diagnostic value of high ABI to CVD and PAD was determined. Compared with the normal ABI group, the high ABI (>1.3) group had a higher prevalence of CVD and PAD but less than the low ABI (≤0.9) group. High ABI was an independent risk factor for the development of CVD and PAD. Receiver-operating characteristic curve analysis showed that the optimal cutoff of high ABI to predict CVD and PAD was 1.43 and 1.45, respectively. The odds ratio of high ABI for CVD and PAD was 2.25 and 6.97, respectively, after adjusting for other confounding risk factors. In conclusion, high ABI indicated the risk of CVD and PAD in Chinese populations with T2DM.

Association between serum cystatin C and diabetic peripheral neuropathy: a cross-sectional study of a Chinese type 2 diabetic population

OBJECTIVE

Serum cystatin C (CysC) is a sensitive marker of kidney function and recent studies have shown that CysC plays a critical role in degenerative diseases in both the central and the peripheral nervous systems. The aim of this study was to explore the relationship between serum CysC and diabetic peripheral neuropathy (DPN) in patients with type 2 diabetes.

METHODS

In total, 937 type 2 diabetic patients were enrolled in this cross-sectional study. Serum CysC concentration was measured by immunoturbidimetry. DPN was evaluated by neurological symptoms, neurological signs, neurothesiometer, and electromyogram.

RESULTS

Serum CysC levels were significantly higher in DPN patients (1.3 (1.1-1.5) mg/l) compared with patients with signs of DPN (1.1 (0.9-1.3) mg/l, P<0.001) and non-DPN patients (1.0 (0.9-1.3) mg/l, P<0.001). Multiple regression analysis revealed that DPN was associated with age, diabetes duration, HbA1c, and serum CysC. Spearman's correlation analysis showed that serum CysC was closely related with age, sex, diabetes duration, hypertension, glomerular infiltration rate, and serum creatinine (Cr) level. The patients were divided into quartiles according to the serum CysC levels. Compared with quartile 1 (referent), the risk of DPN was significantly higher in quartile 2 (odds ratio (OR), 1.753; 95% CI, 1.055-2.912; P<0.05), quartile 3 (OR, 2.463; 95% CI, 1.445-4.917; P<0.01), and quartile 4 (OR, 5.867; 95% CI, 2.075-16.589; P<0.01). Receiver-operating characteristic analysis revealed that the optimal cutoff point of serum CysC to indicate DPN was 1.25 mg/l in male patients and 1.05 mg/l in female patients. High serum CysC level indicated a onefold higher risk of DPN.

CONCLUSIONS

High serum CysC level is closely associated with DPN and may be a potential biomarker for DPN in type 2 diabetic patients.

Vibration perception threshold for sight-threatening retinopathy screening in type 2 diabetic outpatients

OBJECTIVE

We investigated the relationship between vibration perception threshold and diabetic retinopathy and verified the screening value of vibration perception threshold for severe diabetic retinopathy.

METHODS

A total of 955 patients with type 2 diabetes were recruited and divided into three groups according to their fundus oculi photography results: no diabetic retinopathy (n = 654, 68.48%), non-sight-threatening diabetic retinopathy (n = 189, 19.79%) and sight-threatening diabetic retinopathy (n = 112, 11.73%). Their clinical and biochemical characteristics, vibration perception threshold and the diabetic retinopathy grades were detected and compared.

RESULTS

There were significant differences in diabetes duration and blood glucose levels among three groups (all p < 0.05). The values of vibration perception threshold increased with the rising severity of retinopathy, and the vibration perception threshold level of sight-threatening diabetic retinopathy group was significantly higher than both non-sight-threatening diabetic retinopathy and no diabetic retinopathy groups (both p < 0.01). The prevalence of sight-threatening diabetic retinopathy in vibration perception threshold >25 V group was significantly higher than those in 16-24 V group (p < 0.01). The severity of diabetic retinopathy was positively associated with diabetes duration, blood glucose indexes and vibration perception threshold (all p < 0.01). Multiple stepwise regression analysis proved that glycosylated haemoglobin (β = 0.385, p = 0.000), diabetes duration (β = 0.275, p = 0.000) and vibration perception threshold (β = 0.180, p = 0.015) were independent risk factors for diabetic retinopathy. Receiver operating characteristic analysis further revealed that vibration perception threshold higher than 18 V was the optimal cut point for reflecting high risk of sight-threatening diabetic retinopathy (odds ratio = 4.20, 95% confidence interval = 2.67-6.59).

CONCLUSION

There was a close association between vibration perception threshold and the severity of diabetic retinopathy. vibration perception threshold was a potential screening method for diabetic retinopathy, and its optimal cut-off for prompting high risk of sight-threatening retinopathy was 18 V.

Cystatin C: a strong marker for lower limb ischemia in Chinese type 2 diabetic patients?

OBJECTIVE

Cystatin C is growing to be an ideal indicator for renal function and cardiovascular events. The aim of this study was to investigate the relationship between serum cystatin C levels and peripheral arterial disease and to explore its diagnostic value for lower limb ischemia (LLI) in type 2 diabetic population.

METHODS

A total of 1609 T2DM patients were included in this cross-sectional study. Their clinical and biochemical characteristics, ankle-brachial index (ABI), carotid and lower extremity arterial ultrasound were detected. LLI was defined by ABI <0.9 and lower extremity arterial stenosis >50% by ultrasound examination. Patients were divided to two groups: with LLI and without. The risk factors of LLI were explored by binary logistic regression analysis.

RESULTS

The serum concentrations of cystatin C were 1.53±0.60 and 1.08±0.30 mg/L in patients with and without LLI, respectively. Binary logistic regression analysis showed that the significant risk factors were cystatin C (P = 0.007, OR = 5.081), the presence of hypertension (P = 0.011, OR = 3.527), age (P<0.001, OR = 1.181), GA (P = 0.002, OR = 1.089) and diabetes duration (P = 0.008, OR = 1.074). The prevalence of coronary artery disease, cerebral infarction and LLI increased with cystatin C (P<0.01), and the prevalence of LLI in patients with cystatin C >1.2 mg/L was much higher than other three quartile groups. Receiver operating characteristic curve analysis revealed the cut point of cystatin C for LLI was 1.2 mg/L. The risk of LLI dramatically increased in patients with cystatin C >1.2 mg/L (OR = 21.793, 95% confidence interval 10.046-47.280, P<0.001). After adjusting for sex, age, duration, HbA1c, GA and hypertension, its OR still remained 3.395 (95% confidence interval 1.335-8.634).

CONCLUSIONS

There was a strong and independent association between cystatin C and limb arterial disease in diabetic population, and cystatin C >1.2 mg/L indicated a great increased risk of LLI.

The evaluation of iron overload through hepcidin level and its related factors in myelodysplastic syndromes

We chose hepcidin and its related factors as evaluating indicators to determine the degrees of iron overload in myelodysplastic syndromes (MDS) patients. A total of 73 patients and 28 healthy volunteers were enrolled in this study. We performed enzyme-linked immunosorbent assay to measure both bone marrow and peripheral blood serum hepcidin. Real-time quantitative polymerase chain reaction was used to determine the gene expression of growth differentiation factor 15 and twisted gastrulation 1. Serum ferritin (SF), C-reactive protein (CRP), and erythropoietin were measured by routine standard laboratory assays. CD4(+) and CD19(+) lymphocytes and Th polarization were detected by flow cytometry. Twenty-four MDS patients were measured their cardiac and liver iron deposition levels through magnetic resonance imaging (MRI) T2* examination. No significant difference was found between the bone marrow hepcidin levels and peripheral blood hepcidin levels (P = 0.134). Stratified according to different World Health Organization subtypes, refractory anemia with ringed sideroblasts patients had the lowest hepcidin levels (105.40 ± 5.13 ng/ml), while refractory anemia with excess blasts-1 had the highest levels (335.71 ± 25.16 ng/ml). Stratified according to International Prognostic Scoring System and WHO Classification-based Prognostic Scoring System, there was a significant difference of hepcidin levels between low-risk group and high-risk group in two systems, respectively (P = 0.033 and 0.009). The hepcidin levels of CD4(+) high-expression group were demonstrated higher than the normal expression groups (P = 0.02), but the CD19(+) high-expression group did not show the same result (P = 0.206). Meanwhile, patients with a Th1 polarization trend had a high level of hepcidin versus normal group (P < 0.001). Liver iron concentration (LIC) measured by MRI T2* had a closer correlation (r = 0.582, P < 0.001) to hepcidin than serum ferritin, by stepwise regression. C-reactive protein and LIC seemed to be the key determinants of hepcidin, by multivariate regression. Inflammation plays an important role in the regulation of hepcidin expression. T-lymphocyte activation and Th polarization trend might participate in the regulatory mechanism partly. The capability of organ iron load assessment of MRI T2* seems better than that of SF. It seems that hepcidin with CRP and LIC measured by MRI T2* are potential indicators of iron overload in MDS patients.

An effective guidewire looping technique for the recanalization of occlusive segments of infrapopliteal vessels

Objective

To determine the efficacy, safety and primary follow-up results of a guidewire looping technique for the treatment of infrapopliteal arteries.

Materials and Methods

From October 2006 to May 2008, an intraluminal angioplasty of the infrapopliteal arteries was attempted in 200 consecutive patients. Altogether, 417 infrapopliteal lesions, with lengths varying from 2 cm to 32 cm, were treated as part of this study, including 305 lesions in the anterior tibial arteries, 89 in the posterior tibial arteries, and 23 in the peroneal arteries. The 'U'-shaped guidewire technique was attempted in 393 lesions from 361 limbs. The tip of a hydrophilic 0.035-inch guidewire was formed into a 'U' shape with the aid of a 4-Fr catheter and collateral branch vessel to recanalize the completely occluded long segment lesions.

Results

A successful angioplasty with at least one artery recanalized directly to the malleolar or dorsal foot was achieved in 322 limbs (89%). The looping technique had a success rate of 90% (352 of 393 lesions). After the procedure, the rest pain was relieved in 58 of 69 patients, while 207 of 245 limbs (85%) showed improvement for intermittent claudication. Complete wound healing was noted in 21 of 54 patients, while 20 of 54 patients showed an improvement in the wound size or depth. A total of 38 major immediate procedure-related complications were noted, including retroperitoneal hematoma, distal emboli, and vessel rupture.

Conclusion

The results of this study suggests that the guidewire looping technique is a safe and effective method for the recanalization of the occluded lesions in infrapopliteal vessels.

Microvessel changes after post-ischemic benign and malignant hyperemia: experimental study in rats

Background

The present investigation was designed to elucidate the use of dynamic contrast enhanced perfusion MR imaging (DCE pMRI) in characterizing hyperemia, including microvessel changes, and to examine whether DCE pMRI can predict benign or malignant hyperemia.

Methods

Sprague-Dawley rats underwent middle cerebral artery occlusion (MCAO) by intraluminal suture placement. All rats were randomized to 4 groups: MCAO for 0.5 hours followed by saline treatment (10 ml/kg; group 1); MCAO for 3 hours followed by treatment with saline (group 2) or urokinase (25000 IU/kg; group 3); and MCAO for 6 hours followed by urokinase treatment (group 4). Relative cerebral blood volume (rCBV) and relative maximum slope of increase of the signal intensity time curve (rMSI) were quantitatively analyzed from MRI. Microvessel diameter and blood-brain barrier disruption obtained by laser scanning confocal microscopy (LSCM) as well as transmission electron microscopy (TEM) were obtained for correlative study.

Results

Benign hyperemia was noticed only in group 1; malignant hyperemia was seen in group 3. Although the rCBV of malignant hyperemia was slightly higher than in benign hyperemia (P > 0.05), the rMSI, on the other hand, was significantly lower (P < 0.05). Fluoro-isothiocyanate dextran (FITC-dextran) extravasations, marked glial end-foot process swelling, and significant vasodilatation were seen in malignant hyperemia, while no or mild leakage of FITC-dextran and slight glial end-foot process swelling occurred in benign hyperemia.

Conclusion

Our findings indicate that DCE pMRI can characterize post-ischemic hyperemia and correlates well with microvascular damage.

Directed engineering of umbilical cord blood stem cells to produce C-peptide and insulin

OBJECTIVES

In this study, we investigated the potential of umbilical cord blood stem cell lineages to produce C-peptide and insulin.

MATERIALS AND METHODS

Lineage negative, CD133+ and CD34+ cells were analyzed by flow cytometry to assess expression of cell division antigens. These lineages were expanded in culture and subjected to an established protocol to differentiate mouse embryonic stem cells (ESCs) toward the pancreatic phenotype. Phase contrast and fluorescence immunocytochemistry were used to characterize differentiation markers with particular emphasis on insulin and C-peptide.

RESULTS

All 3 lineages expressed SSEA-4, a marker previously reported to be restricted to the ESC compartment. Phase contrast microscopy showed all three lineages recapitulated the treatment-dependent morphological changes of ESCs as well as the temporally restricted expression of nestin and vimentin during differentiation. After engineering, each isolate contained both C-peptide and insulin, a result also obtained following a much shorter protocol for ESCs.

CONCLUSIONS

Since C-peptide can only be derived from de novo synthesis and processing of pre-proinsulin mRNA and protein, we conclude that these results are the first demonstration that human umbilical cord blood-derived stem cells can be engineered to engage in de novo synthesis of insulin.

Differential expression of peroxisome proliferator-activated receptors alpha and gamma gene in various chicken tissues

The peroxisome proliferator-activated receptors (PPARs) are the members of superfamily of nuclear hormone receptors. A great number of studies in rodent and human have shown that PPARs were involved in the lipids metabolism. The goal of the current study was to investigate the expression pattern of PPAR genes in various tissues of chicken. The tissue samples (heart, liver, spleen, lung, kidney, stomach, intestine, brain, breast muscle and adipose) were collected from six Arber Acres broilers (8 weeks old, male and female birds are half and half). Semi-quantitative RT-PCR and Northern blot were used to characterize the expression of PPAR-alpha and PPAR-gamma genes in the above tissues. By semi-quantitative RT-PCR, the results showed the expression level of PPAR-alpha gene was higher in brain, lung, kidney, heart and intestine, medium in stomach, liver and adipose than in spleen, and it did not express in breast muscle. The expression level of PPAR-gamma gene was higher in adipose, medium in brain and kidney than in spleen, heart, lung, stomach and intestine, but it did not express in liver and breast muscle. Northern blot results showed that PPAR-alpha gene expressed in heart, liver, kidney and stomach, and the intensity of hybridization signal was the stronger in liver and kidney than in other tissues, however, PPAR-gamma gene only expressed in adipose and kidney tissues. The results of this study showed the profile of PPAR gene expression in the chicken was similar to that in rodent, human and pig. However the expression profile of chicken also have its own specific trait, i.e. compared with mammals, PPAR-alpha gene can not be detected in skeletal muscle and PPAR-gamma gene can be stronger expressed in kidney tissues. This work will provide some basic data for the PPAR genes expression and lipids metabolism of birds.

Time-resolved infrared spectroscopic study of the switching dynamics of a surface-stabilized ferroelectric liquid crystal

The orientation dynamics of a ferroelectric liquid crystal with a naphthalene ring (FLC-3) during the electric-field-induced switching between two surface-stabilized states was investigated by means of time-resolved Fourier-transform infrared spectroscopy. Time-resolved infrared spectra of the planar-aligned cell of FLC-3 were measured as a function of the polarization angle ranging from 0 degree to 180 degrees under a rectangular electric field +/-40 V with a 5-kHz repetition rate in the smectic-C* (Sm-C*) phase at 137 degrees C. From these spectra details about the mutual arrangement of different molecular segments at all the delay times in the Sm-C* phase were derived. It was found that the C=O group in the core moiety exhibits a dynamical behavior different from that in the chiral moiety during the electric-field-induced switching between the two surface-stabilized states. The most important finding in the present study is that during the electric-field-induced switching the FLC molecule not only rotates around the layer normal, but also revolves around its own long axis. Furthermore, time-resolved infrared spectroscopy revealed that each group in the core moiety passes almost simultaneously through the projection of the layer normal in the cell window during the dynamic switching.

[Effects of composition of mobile phases on retention behavior of solutes in hydrophobic interaction chromatography]

The retention behavior of aromatic alcohol homologues in hydrophobic interaction chromatography (HIC) was investigated for the first time. The differences in retention behavior between proteins and small solutes, and the eluted range and ability of different salts to small solutes and biopolymers, are elucidated with the parameter Z of the stoichiometric displacement retention model. The retention of aromatic alcohols follows the homologue rule. By the comparison of the changes of Z in different salt solutions, it is found that for small molecules the salt type only changes the hydration degree; but for proteins, it not only changes the hydration of proteins and stationary phase, but also affects the conformation of protein molecules near the contact regions between the protein and the stationary phase surface.

Polarized infrared spectroscopic study on the orientation of the molecules in the smectic-C* phase of a ferroelectric liquid crystal with a naphthalene ring: alternative theory for the analysis of polarization-angle-dependent intensity changes

A theory to explain the polarization-angle dependence of polarized infrared spectra of a ferroelectric liquid crystal in the surface-stabilized ferroelectric liquid crystal state is proposed. It describes the relationship between the intensity of the absorption bands and the polarization angle of the infrared radiation. Using this theory the polarization-angle dependence of the infrared band intensities was analyzed for a ferroelectric liquid crystal with a naphthalene ring and two phenyl rings with a stacked layer structure in the smectic-C* phase. The polarization-angle-dependent spectra were measured at 137 degrees C under external dc electric fields of +40 and -40 V to investigate the orientation of the molecules. Plots of the infrared absorbance versus polarization angle for representative bands were subjected to a curve fitting procedure by a least squares method. From the curves obtained the orientation of the transition dipole moments with respect to the molecular long axis and the orientation of the molecular long axis with respect to the rubbing direction of the cell were estimated based upon the suggested theory. The polarization-angle-dependent infrared spectra obtained were also analyzed by two-dimensional (2D) correlation spectroscopy. The 2D correlation analysis clearly detects a slight phase difference in the polarization-angle dependence which is hardly recognized in ordinary plots of the intensity changes in the infrared bands. The 2D correlation analysis allows us to separate asymmetric and symmetric stretching bands due to the chiral methyl group from those arising from other methyl groups in the alkyl chains.

GTP hydrolysis by transitional endoplasmic reticulum from rat liver inhibited by all-trans-retinol

GTP hydrolysis by an endoplasmic reticulum fraction from rat liver enriched in part-rough, part-smooth transition elements was inhibited by all-trans-retinol half maximally at a concentration of about 10 micrograms/ml. Similar results were obtained with GTPase activity partially purified by ion-exchange (DE-52) chromatography. The inhibition was non-competitive and given by both retinol and retinaldehyde but not by retinoic acid or alpha-tocopheryl acetate. The hydrolysis of other nucleoside di- and triphosphates was much less affected by retinol. The activity was inhibited by detergents but at much higher concentrations than by retinol. The results suggest that enhancement of cell-free transfer from endoplasmic reticulum to Golgi apparatus by retinol observed previously at low concentrations of cytosol may be mediated through an interaction with GTP.