Motion induced phase error reduction using a Hilbert transform

Object motion can introduce phase error and thus measurement error for phase-shifting profilometry. This paper proposes a generic motion error compensation method based on our finding that the dominant motion-introduced phase error doubles the frequency of the projected fringe frequency, and the Hilbert transform shifts the phase of a fringe pattern by π/2. We apply a Hilbert transform to phase-shifted fringe patterns to generate another set of fringe patterns, calculate one phase map using the original fringe patterns and another phase map using Hilbert transformed fringe patterns, and then use the average of these two phase maps for three-dimensional reconstruction. Both simulation and experiments demonstrated that the proposed method can substantially reduce motion-introduced measurement error.

Type 1 innate lymphoid cells are associated with type 2 diabetes

AIM

Type 1 innate lymphoid cells (ILC1s) play a major role in regulating systemic inflammatory diseases. However, the relationship between ILC1s and type 2 diabetes (T2D) remains unclear. Thus, the present study investigated the relationship between ILC1s and glucose homoeostasis in humans.

METHODS

A total of 37 newly diagnosed T2D patients and 32 subjects with normal glucose tolerance (NGT), matched for age and body mass index (BMI), were enrolled in the study. Flow cytometric analysis of ILC1s derived from peripheral blood mononuclear cells (PBMCs) and omental adipose tissue was performed.

RESULTS

T2D patients displayed greater numbers and frequencies of circulating and adipose tissue ILC1s (P < 0.05) compared with NGT subjects, and the two types of ILC1s correlated positively with each other. Circulating ILC1s were positively associated with glycated haemoglobin (HbA_1c), fasting plasma glucose (FPG), homoeostasis model assessment for insulin resistance (HOMA-IR), adipose tissue insulin resistance index (Adipo-IR) and serum free fatty acids (FFAs). A logistic regression model revealed that patients with higher ILC1 levels exhibited a 13.481-fold greater risk of developing T2D.

CONCLUSION

This study is the first to provide evidence that ILC1 abnormalities are involved in the development of diabetes. The data also suggest a potential role of ILC1s as therapeutic indicators in the treatment of T2D.

[Clinical cohort study of imaging evaluation and postoperative pathology of carotid vulnerable plaque]

Objective: To evaluate the accuracy of contrast-enhanced ultrasound(CEUS) scanning in identifying vulnerable plaque in carotid artery. Methods: The study included a total of 25 patients who suffered from carotid artery stenosis and underwent carotid endarterectomy from January 2016 to December 2017 in Beijing Tsinghua Changgung Hospital, School of Clinical Medicine, Tsinghua University. Preoperative carotid artery contrast enhanced ultrasound and High-resolution MRI were performed to all patients to determine whether the plaques were stable. All patients then underwent carotid endarterectomy, during which, plaques were completely removed. Biopsies were performed using HE staining and CD31, CD34 and SMA immunohistochemistry was used to identify the plaques properties, including the thickness and integrity of the fiber cap, neovascular endothelium, hemorrhage, and inflammatory cells in the removed plaques.The results of these tests were compared with the diagnosis through the pre-operative imaging. Results: Among twenty-five cases, the pre-operative CEUS revealed sixteen with unstable plaques and nine with stable plaques. Meanwhile the post-operation pathology confirmed seventeen cases with unstable plaque components. The sensitivity of CEUS in the identification of carotid vulnerable plaque was 88.2%(15/17), the specificity was 87.5%(7/8), and the overall diagnostic accuracy was 88%(22/25). The sensitivity, specificity and overall diagnostic accuracy of high resolution MR for vulnerable plaque identification were 83.3%(10/12), 71.4%(5/7), 78.9%(15/19), respectively. There were no significant difference between two groups(χ(2)=0.003, P>0.05). Conclusions: The sensitivity, specificity and overall diagnostic accuracy of the CEUS for vulnerable plaque identification are high.Therefore, CEUS is recommended as one of the pre-operative diagnostic method for unstable plaque in carotid stenosis.

Dynamic anticrack propagation in snow

Continuum numerical modeling of dynamic crack propagation has been a great challenge over the past decade. This is particularly the case for anticracks in porous materials, as reported in sedimentary rocks, deep earthquakes, landslides, and snow avalanches, as material inter-penetration further complicates the problem. Here, on the basis of a new elastoplasticity model for porous cohesive materials and a large strain hybrid Eulerian–Lagrangian numerical method, we accurately reproduced the onset and propagation dynamics of anticracks observed in snow fracture experiments. The key ingredient consists of a modified strain-softening plastic flow rule that captures the complexity of porous materials under mixed-mode loading accounting for the interplay between cohesion loss and volumetric collapse. Our unified model represents a significant step forward as it simulates solid-fluid phase transitions in geomaterials which is of paramount importance to mitigate and forecast gravitational hazards.

Anticrack propagation in snow results from the mixed-mode failure and collapse of a buried weak layer and can lead to slab avalanches. Here, authors reproduce the complex dynamics of anticrack propagation observed in field experiments using a Material Point Method with large strain elastoplasticity.

[Glucocorticoids and liver diseases]

Glucocorticoids is a type of steroid hormone secreted from zona fasciculata of adrenal cortex.As an immune and inflammatory inhibitor, glucocorticoids has been used to treat many kinds of diseases.T cell response plays a crucial role in the pathogenesis of liver diseases. However, the role of glucocorticoids in the mechanism and treatment of liver disease in current clinical practice is controversial. This paper summarizes the progress of glucocorticoid use for the treatment of liver diseases in recent years. References will be provided for how to grasp the indications,application timing and proper dosage of glucocorticoids in liver diseases.

Impedance-based sensor for potassium ions

A conductometric sensor for potassium ions in solution is presented. Interdigitated, planar gold electrodes were coated with a potassium-selective polymer membrane composed of a poly(vinyl chloride) matrix with about 65 wt% of plasticiser and 2-5 wt% of a potassium-selective ionophore. The impedance of the membrane was measured, using the electrodes as a transducer, and related to the concentration of potassium in a sample solution in contact with the membrane. Sensitivity was optimised by varying the sensor components, and selectivity for potassium over sodium was also shown. The resulting devices are compact, miniature, robust sensors which, by means of impedance measurements, eliminate the need for a reference electrode. The sensor was tested for potassium concentration changes of 2 mM across the clinically relevant range of 2.7-18.7 mM.

Treatment of hepatocellular carcinoma in the caudate lobe: US-guided percutaneous radiofrequency ablation combined with ethanol ablation

AIM

To evaluate the technical feasibility and treatment results of ultrasound (US)-guided percutaneous radiofrequency ablation (RFA) combined with ethanol ablation (EA) for hepatocellular carcinoma (HCC) in the caudate lobe.

MATERIALS AND METHODS

The institutional review board approved this retrospective study and the requirement for informed consent was waived. From October 2009 to June 2016, there were 49 patients with HCC in the caudate lobe underwent ablation. Among them, 14 patients (12 men and two women, mean age: 49.9±14.9 years) with 16 caudate lobe HCCs (mean size: 3±1.1 cm) who underwent US-guided RFA-EA were identified. These patients were compared with patients who underwent RFA alone (n=17) and EA alone (n=18).

RESULTS

HCCs in the RFA-EA group were larger than those in the EA-alone group (3±1.1 versus 2.1±0.7 cm, p=0.028). In the RFA-EA group, all the patients achieved treatment success (14/14) and entered follow-up. After a follow-up period of 17.1±10.6 months (range, 5-36 months), local tumour progression (LTP) was detected in four tumours. The 1- and 2-year LTP rates after RFA-EA were 18.8% and 27.8%, respectively. The 1- and 2-year disease-free survival (DFS) rates were 35.7% and 13.4%. Six patients died, with the 1-, 2-, and 3-year overall survival (OS) rates of 85.1%, 63.1%, and 21%, respectively. There were no significant differences in the LTP, DFS, and OS rates between the RFA-EA group and RFA-alone or EA groups (p=0.363-0.733).

CONCLUSION

US-guided percutaneous RFA-EA appears to be a feasible and effective treatment for HCC in the caudate lobe.

A comparison of the biomechanical stability of pedicle-lengthening screws and traditional pedicle screws: an in vitro instant and fatigue-resistant pull-out test

Aims

The aim of this study was to compare the peak pull-out force (PPF) of pedicle-lengthening screws (PLS) and traditional pedicle screws (TPS) using instant and cyclic fatigue testing.

Materials and Methods

A total of 60 lumbar vertebrae were divided into six groups: PLS submitted to instant pull-out and fatigue-resistance testing (groups A1 and A2, respectively), TPS submitted to instant pull-out and fatigue-resistance testing (groups B1 and B2, respectively) and PLS augmented with 2 ml polymethylmethacrylate, submitted to instant pull-out and fatigue-resistance testing (groups C1 and C2, respectively). The PPF and normalized PPF (PPFn) for bone mineral density (BMD) were compared within and between all groups.

Results

In all groups, BMD was significantly correlated with PPF (r = 0.83, p < 0.001). The PPFn in A1 was significantly less than in B1 (p = 0.006) and C1 (p = 0.002). The PPFn of A2 was significantly less than in B2 (p < 0.001) and C2 (p < 0.001). The PPFn in A1, B1, and C1 was significantly greater than in A2 (p = 0.002), B2 (p = 0.027), and C2 (p = 0.003). There were no significant differences in PPFn between B1 and C1, or between B2 and C2.

Conclusion

Pedicle lengthening screws with cement augmentation can provide the same fixation stability as traditional pedicle screws and may be a viable clinical option. Cite this article: Bone Joint J 2018;100-B:516-21.

4218T/C polymorphism associations with post-cesarean patient-controlled epidural fentanyl consumption and pain perception

BACKGROUND

The utilization of intrathecal opioids is an efficacious component of post-cesarean section pain management. Given that growing evidence indicates that calcitonin gene-related peptide (CGRP) plays a key role in the development of peripheral sensitization and is associated with enhanced pain, we hypothesized that CGRP 4218T/C polymorphism is associated with the variability in fentanyl consumption for post-cesarean analgesia.

METHODS

We recruited 548 patients who presented for elective cesarean delivery, and used polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method to analyze CGRP 4218T/C polymorphism. We examined the association of CGRP 4218T/C polymorphism and post-operative fentanyl consumption for analgesia as well as adverse reactions to fentanyl in those patients who received cesarean section surgeries.

RESULTS

We found that the CGRP 4218T/C polymorphism has a significant effect on pain perception, analgesic requirement, and nausea and vomiting for the first 24 h after cesarean delivery in patients who received PCEA fentanyl. Individuals with the C/C genotype had more pain, required more PCEA fentanyl, and experienced a lower incidence of nausea and vomiting.

CONCLUSION

These results indicated that patients with C/C genotype may have reduced sensitivity to fentanyl analgesia and/or increased pain perception, and were more willing to use PCEA fentanyl to manage their pain.