Assessment of Computed Tomography Imaging for Isolated Type 1 Bicuspid Aortic Valve Repair: A Comparison between Internal and External Suture Annuloplasty Techniques.

Background: The ideal position of suture annuloplasty relative to the aortic annulus (internal or external) remains unclear. This study aimed to investigate the effectiveness of internal and external suture annuloplasty for isolated type 1 bicuspid aortic valve (BAV) repair. Electrocardiogram (ECG)-gated computed tomography (CT) was used to compare the two techniques and analyze their impact on the aortic annulus. Methods: We retrospectively analyzed 20 patients who underwent isolated type 1 BAV repair with either internal or external suture annuloplasty. Each group included 10 patients with comparable clinical features. Preoperative and postoperative ECG-gated CT scans were performed to assess the anatomical relationship between the ventricular-aortic junction (VAJ) and virtual basal ring (VBR), and to measure the height of annuloplasty from the VBR at predefined landmarks in both groups. Perioperative annular geometries, including annular area and perimeter, were measured to quantify the impact of annuloplasty on annular expansibility. The discrepancy between the postoperative annular dimension and size of the Hegar dilator were compared between groups to evaluate the effectiveness of annuloplasty. Results: In both groups, VAJ was higher than VBR at the right coronary (RC) ostium (7.7 ± 3.3 mm) and the raphe (7.9 ± 1.5 mm). The height from the VBR to the external suture annuloplasty shared a similar pattern at the RC ostium and raphe (5.3 ± 1.1 mm and 4.8 ± 1.0 mm, respectively). In contrast, the height differences were minimal for these landmarks in the internal group. Postoperative annular area expansibility decreased in the internal group compared to preoperative levels (4.9 ± 2.3% vs. 8.9 ± 5.5%, p = 0.038), while no significant change was found in the external group (7.6 ± 4.1% vs. 6.5 ± 2.8%, p = 0.473). The internal group showed less area discrepancy between the VBR and the Hegar dilator both at systole (10.1 ± 3.7% vs. 30.1 ± 16.6%, p = 0.004) and diastole (5.7 ± 4.9% vs. 20.9 ± 14.5%, p = 0.009) compared to the external group. Conclusions: Internal suture annuloplasty results in better positioning relative to the VBR than external suture annuloplasty due to the absence of VAJ interference. While this results in more precise annular reduction and less expansibility in the short term, a long-term follow-up evaluation is necessary to assess its effectiveness.

A wireless magnetic resonance energy transfer system for micro implantable medical sensors.

Based on the magnetic resonance coupling principle, in this paper a wireless energy transfer system is designed and implemented for the power supply of micro-implantable medical sensors. The entire system is composed of the in vitro part, including the energy transmitting circuit and resonant transmitter coils, and in vivo part, including the micro resonant receiver coils and signal shaping chip which includes the rectifier module and LDO voltage regulator module. Transmitter and receiver coils are wound by Litz wire, and the diameter of the receiver coils is just 1.9 cm. The energy transfer efficiency of the four-coil system is greatly improved compared to the conventional two-coil system. When the distance between the transmitter coils and the receiver coils is 1.5 cm, the transfer efficiency is 85% at the frequency of 742 kHz. The power transfer efficiency can be optimized by adding magnetic enhanced resonators. The receiving voltage signal is converted to a stable output voltage of 3.3 V and a current of 10 mA at the distance of 2 cm. In addition, the output current varies with changes in the distance. The whole implanted part is packaged with PDMS of excellent biocompatibility and the volume of it is about 1 cm(3).

Relationship Between Leaflets and Root in Normal Aortic Valve Based on Computed Tomography Imaging: Implication for Aortic Valve Repair.

Objective: By assessing the normal dimensions and the relationship between the aortic root and leaflets in Chinese population, the objective of this three-dimensional computed tomography (3DCT)-based study was to establish a matching reference for leaflets and aortic root for aortic valve (AV) repair. Method: Electrocardiogram-gated multi-detector CT was performed on 168 Chinese participants with a normal aortic valve. Measurements of the aortic annuli and leaflets were obtained. The correlations between and the ratios of the specific root and leaflet measurements were analyzed. The references for the leaflet and root dimensions were suggested based on geometric height (gH) using a linear regression equation. The utility of the ratios was tested with CT images of 15 patients who underwent aortic valve repair. Result: The mean annulus diameter (AD), sino-tubular junction (STJ) diameter, geometric height (gH), effective height (eH), free margin length (FML), commissural height (ComH), inter-commissural distance (ICD), and coaptation height (CH) were 22.4 ± 1.7 mm, 27.3 ± 2, 0.4 mm, 15.5 ± 1.7 mm, 8.9 ± 1.2 mm, 32.0 ± 3.4 mm, 17.9 ± 1.9 mm, 23.1 ± 2.3 mm, and 3.1 ± 0.6 mm, respectively. The gH/AD, FML/ICD, and eH/ComH ratios were 0.69 ± 0.07, 1.38 ± 0.08, and 0.50 ± 0.07, respectively. The gH correlated with all other leaflet and root measurements (P < 0.01), whereas the FML demonstrated a better correlation with ICD compared with gH (R2 = 0.75, and R2 = 0.37, respectively). The FML/ICD and eH/ComH ratios might be used to assess leaflet-root mismatch and post-repair leaflet billowing. Conclusion: The normal aortic valve measurements based on 3DCT revealed a specific relationship between the root and leaflets; and this will guide the development of an objective method of aortic valve repair.

A Machine Learning Model to Maximize Efficiency and Face Time in Ambulatory Clinics.

INTRODUCTION: Ambulatory appointments are typically scheduled in fixed increments, resulting in suboptimal time utilization. Advanced analytics are rarely applied to address operational challenges in health care. We sought to develop a machine learning model that predicts the time pediatric urologists require to create a more efficient clinic schedule. METHODS: We prospectively collected data from January to April 2018. Variables included demographics and visit level covariates. The primary outcome was defined as in-room doctor time spent. Univariate analysis was performed. Data were split into train/test in a 4:1 ratio. Separate models using random forest were created for new and return visits. Two out-of-sample clinic days were used to compare the patient wait time between fixed-time visits and machine learning model. Patient punctuality simulation was performed 1,000 times for each day. RESULTS: A total of 256 visits (113 new/143 return) were included. Mean age at visit was 6.47 years. In univariate analysis, longer visits were significantly associated with new patients (p <0.01), testing (p <0.01), older patients and diagnoses like voiding dysfunction and neurogenic bladder. Conversely, morning clinic, previous urological surgery (p <0.01), recent postoperation (p <0.01) and diagnoses like penile complaints and hydrocele were associated with shorter visits. On average, our machine learning model predicted doctor time accurately to 3.6 (new patients) and 5.0 minutes (returning patients). In 1,000 simulated days with random patient punctuality machine learning reduced the wait time by 24% to 54%. CONCLUSIONS: Pediatric urologists' clinic time can be accurately predicted with machine learning models. This insight can be incorporated into a robust scheduling model to minimize patient wait time, increase clinical efficiency and likely improve family satisfaction.

Association of protein kinase CK2 inhibition with cellular radiosensitivity of non-small cell lung cancer.

Protein kinase CK2 is a highly conserved protein Ser/Thr protein kinase and plays important roles in cell proliferation, protein translation and cell survival. This study investigated the possibility of using CK2 inhibition as a new approach for increasing the efficacy of radiotherapy in non-small cell lung cancer (NSCLC) and its underlying mechanisms. Kinase inhibition of CK2 was attempted either by using the specific CK2 inhibitor, Quinalizarin or by applying siRNA interference technology to silence the expression of the catalytic subunit of CK2 in A549 and H460 cells. The results showed that CK2α knockdown or Quinalizarin significantly enhanced the radiosensitivity of various NSCLC cells. The notable findings we observed after exposure to both CK2 inhibition and ionizing radiation (IR) were a prolonged delay in radiation-induced DNA double-strand breaks (DSB) repair, robust G2/M checkpoint arrest and increased apoptosis. In vivo studies further demonstrated that compared with each treatment alone, CK2 inhibition combined with IR reduced tumor growth in the H460 cell xenograft model. In conclusion, CK2 is a promising target for the enhancement of radiosensitivity in NSCLC.

[Effects of complete and incomplete sleep deprivation on immune function of mice].

AIM: To study the interaction between sleep deprivation and immune functions in mice. METHODS: To set up the uncompleted sleep deprivation of mice by means of lighting mimicked with whole day and dark box done with whole night for 2 weeks and to deprive the mice of sleep in the rotating cage for 24 h and 72 h. All mice are challenge with BSA before sleep deprivation. The spleen weight of mice was measured by analytic balance. The count of T subpopulation was detected with FACS. The levels of cytokines IL-2, IL-10 and the concentration of the specific antibody to BSA was detected by ELISA method. RESULTS: Compared with the normal control, the spleen weight of mice in all the other experimental groups was decreased (P<0.05) except those of lighting group. Decrease of CD8+ T lymphocyte was observed (P<0.01) while the ratio CD4/CD8 increased greatly. Augmentation of IL-10 was demonstrated only in the all-light group, both IL-2 and IL-10 decreased (P<0.01) in the other groups. Significant decrease of specific antibody for BSA was found in the mice of sleep deprived group (P<0.01). CONCLUSION: Complete and incomplete sleep deprivation inhibit differently the immune function of mice by triggering decrease of CD8+ T cells, inhibiting secretion of specific antibody and causing disturbance on the pattern of cytokines.