Strategies of reducing input sample volume for extracting circulating cell-free nuclear DNA and mitochondrial DNA in plasma

Background: Circulating cell-free (ccf) DNA in blood has been suggested as a potential biomarker in many conditions regarding early diagnosis and prognosis. However, misdiagnosis can result due to the limited DNA resources in Biobank's plasma samples or insufficient DNA targets from a predominant DNA background in genetic tests. This study explored several strategies for an efficient DNA extraction to increase DNA amount from limited plasma input. Methods: Ccf plasma DNA was extracted with three different methods, a phenol-chloroform-isoamylalcohol (PCI) method, a High Pure PCR Template Preparation Kit method and a method used for single cell PCR in this group. Subsequently, the total DNA was measured by Nanodrop and the genome equivalents (GE) of the GAPDH housekeeping gene and MTATP 8 gene were measured using a multiplex real-time quantitative PCR for the quantitative assessment of nDNA and mtDNA. Results: Instead of 400-800 μL (routine input in the laboratory), 50 μLof plasma input enabled the extraction of ccf DNA sufficient for quantitative analysis. Using the PCI method and the kit method, both nDNA and mtDNA could be successfully detected in plasma samples, but nDNA extracted using protocol for single cell PCR was not detectable in 25% of plasma samples. In comparison to the other two methods, the PCI method showed lower DNA purity, but higher concentrations and more GE of nDNA and mtDNA. Conclusions: The PCI method was more efficient than the other two methods in the extraction of ccf DNA in plasma. Limited plasma is available for ccf DNA analysi

Association between prophylactic hydration volume and risk of contrast-induced nephropathy after emergent percutaneous coronary intervention

Background: Intravenous hydration during percutaneous coronary intervention (PCI) significantly reduces the risk of contrast-induced nephropathy (CIN), but there are no well-defined protocols regard¬ing the optimal hydration volume (HV) required to prevent CIN following emergent PCI. Therefore, this study investigates the association between the intravenous HV and CIN after emergent PCI. Methods: 711 patients were prospectively recruited who had underwent emergent PCI with hydration at routine speed and the relationship was investigated between HV or HV to weight ratio (HV/W) and the CIN risk, which was defined as a ≥ 25% or ≥ 0.5 mg/dL increase in serum creatinine levels from baseline within 48–72 h of exposure to the contrast. Results: The overall CIN incidence was 24.7%. Patients in the higher HV quartiles had elevated CIN rates. Multivariate analysis showed that higher HV/W ratios were not associated with a decreased risk (using the HV) of CIN, but they were associated with an increased risk (using the HV/W) of CIN (Q4 vs. Q1: adjusted odds ratio 1.99; 95% confidence interval 1.05–3.74; p = 0.034). A higher HV/W ratio was not significantly associated with a reduced risk of long-term death (all p > 0.05). Conclusions: The data suggests that a higher total HV is not associated with a decreased CIN risk or beneficial long-term prognoses, and that excessive HV may increase the risk of CIN after emergent PCI

Hollow Effect of Ground Vibration Induced by Electronic Detonator in Shallow Tunnel

Blasting excavation is extensively used in tunnel construction, and the adverse effect of ground vibration induced by blasting on surrounding structures and inhabitants is a critical problem. This study aims to investigate the tunnel hollow effect on triaxial peak particle velocities (PPV) and dominant frequencies induced by electronic detonator. Field experiments were conducted in a shallow tunnel construction site and the ground vibration waveforms were recorded. Variational mode decomposition (VMD) was applied to denoise and correct the zero-drift phenomenon, and the proposed method of selecting the optimal parameter was verified. A series of statistical analyses and tests were performed to evaluate the differences of peak particle velocity and dominant frequency among various monitoring points. The results showed that the hollow effect on Z-axis PPV is significant, and triaxial PPV is also affected when the horizontal distance exceeds 30 m. The hollow effect on dominant frequency could not be identified since the hollow of tunnel is a free face, and the dominant frequency of reflected wave remains unchanged. An augmented factor of 1.229 is determined carefully as the hollow effect factor on PPV. Therefore, blasting vibration induced by electronic detonator of the excavated zone should be attached with greater importance, and hollow effect on PPV should be considered in the blasting design of tunnel excavation

Feasibility of Retrograde Recanalization of Occluded Radial Artery via Distal Transradial Artery Approach: a Single-center Prospective Study

Background The incidence of radial artery occlusion (RAO) after coronary intervention via transradial artery approach (TRA) is high. But there is a lack of long-term follow-up studies with a large sample size on retrograde recanalization of occluded radial artery via distal transradial artery approach (dTRA) . Objective To assess the feasibility of dTRA for retrograde recanalization of occluded radial artery. Methods Forty-four patients undergoing retrograde recanalization via dTRA for treating RAO after coronary intervention via TRA were consecutively recruited from Shenzhen People's Hospital from June 2019 to December 2021. The primary observation index was postprocedural radial artery patency. And secondary observation index included possible predictors of failed retrograde recanalization, incidence of adverse events during hospitalization, and patency rates of radial artery at 3, 6 and 12 months after procedure. Results The success rate of postprocedural radial artery patency was 88.6% (39/44) , and divided into groups of successful (n=39) and failed (n=5) according to the result of the procedure. Compared with the successful group, the failed group had higher percentages of diabetics, current smokers and chronic total occlusion of the coronary artery, as well as a significantly lower prevalence of undergoing balloon angioplasty (P<0.05) . There was significant intergroup difference in the times of coronary interventions (P<0.05) ; there was no significant intergroup difference in the incidence of bleeding or hematoma at the access site during hospitalization (P>0.05) . The patency rates of radial artery in successful group were 48.7% (19/39) , 43.6% (17/39) , and 35.9% (14/39) at 3, 6, and 12 months after procedure, respectively. Conclusion The dTRA may be feasible for retrograde recanalization of occluded radial artery, which showed a high procedural success rate up to 88.6%, but the long-term patency rate was less than 50.0%. Diabetes, smoking, times of coronary interventions, chronic total occlusion of coronary artery, and receiving no balloon angioplasty may be influencing factors of failed retrograde recanalization of occluded radial artery via dTRA. And dTRA for retrograde recanalization of occluded radial artery is recommended for patients with RAO who also require elective coronary intervention

Efficient Hydrogen Peroxide (H2O2) Synthesis by CaSnO3 via Two-Electron Water Oxidation Reaction

Electrochemical in situ hydrogen peroxide (H2O2) generation from a two-electron water oxidation reaction (2e-WOR) is a challenge, not only on catalyst selection but also on electrode making. Herein, the H2O2 electrocatalyst CaSnO3 nanoparticles were prepared by low-cost glucose as an agent and characterized by X-ray diffraction (XRD), thermogravimetric and differential scanning calorimetry (TG-DSC), Fourier transform infrared spectra (FT-IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). The active sites for the OH- adsorption on the surface CaSnO3 (121) was identified by density functional theory (DFT) calculation, and the corresponding reaction mechanism of H2O2 formation was proposed. The CaSnO3 nanoparticles can be formed from 650 to 850 degrees C, and the particle sizes are in the range of 27.2-37.3 nm. The mechanism of catalyst formation is that species of Ca and Sn reacted with oxygen to generate CaO and SnO2 during low-temperature calcination and CaSnO3 generated during high-temperature calcination. The active sites are the coordination-unsaturated Sn ions, which easily adsorb the negative-charge OH- from the solution, forming an OH* intermediate, and two adsorbed OH* can combine to generate a neutral H2O2 molecule. The H2O2 generation rate over CaSnO3 was calcinated at 850 degrees C is 347.7 mu mol.min(-1).g(-1) at 2.6 V versus Ag/AgCl under dark conditions. The work opens an in situ H2O2 generation route, direct water oxidation, with wide application prospects

Hypothermia activates adipose tissue to promote malignant lung cancer progression.

Microenvironment has been increasingly recognized as a critical regulator of cancer progression. In this study, we identified early changes in the microenvironment that contribute to malignant progression. Exposure of human bronchial epithelial cells (BEAS-2B) to methylnitrosourea (MNU) caused a reduction in cell toxicity and an increase in clonogenic capacity when the temperature was lowered from 37°C to 28°C. Hypothermia-incubated adipocyte media promoted proliferation in A549 cells. Although a hypothermic environment could increase urethane-induced tumor counts and Lewis lung cancer (LLC) metastasis in lungs of three breeds of mice, an increase in tumor size could be discerned only in obese mice housed in hypothermia. Similarly, coinjections using differentiated adipocytes and A549 cells promoted tumor development in athymic nude mice when adipocytes were cultured at 28°C. Conversely, fat removal suppressed tumor growth in obese C57BL/6 mice inoculated with LLC cells. Further studies show hypothermia promotes a MNU-induced epithelial-mesenchymal transition (EMT) and protects the tumor cell against immune control by TGF-β1 upregulation. We also found that activated adipocytes trigger tumor cell proliferation by increasing either TNF-α or VEGF levels. These results suggest that hypothermia activates adipocytes to stimulate tumor boost and play critical determinant roles in malignant progression

Hypothermia suppressed MNU-mediated cytotoxicity and promoted cell clonogenic capacity.

<p>A. Hypothermia suppressed MNU-induced BEAS-2B cytotoxicity examined by MTT. B and C. Hypothermia decreased MNU-induced BEAS-2B cell apoptosis examined by PI and Annexin V-FITC staining, early apoptosis and late apoptosis were determined as the percentage of Annexin V+/PI- cells and Annexin V+/PI+ cells, respectively. D. Hypothermia promoted MNU-induced BEAS-2B cell clonogenic capacity examined by soft agar assay. Data were expressed as mean ± SD. One asterisk (*)<0.001 as compared to 37°C condition (n = 5).</p

The hypothermia-activated adipocytes promoted lung cancer progression by TGF-β1 and TNF-α.

<p>A. TGF-β1 neutralization relative to MNU alone down-regulated epithelial marker E-cadherin and upregulated mesenchymal markers, such vimentin and fibronectin, and adding TGF-β1 to cells had opposite action in MNU-treated BEAS-2B cells (n = 5). B. TGF-β1 neutralization relative to control promoted CD8+ T cell-mediated cytotoxicity at 37°C and adding TGF-β1 to cells suppressed CD8+ cell-mediated cytotoxicity in A549 cells (n = 5). C. Xenografts of coinjection using A549 cells and 28°C-cultured adipocytes grew rapidly relative to A549 single injection (n = 10). D. A coinjection using either TNF-α or VEGF and A549 cells promoted xenograft development, whereas pre-cultured adipocytes by a TNF-α or VEGF blocking antibody prevented xenograft development relative to A549 single injection (n = 10). Data were expressed as mean ± SD. One asterisk (<b>*</b>)<0.001.</p

Effect of neutralization of TNF-α or TGF-β1 on colony formation and cytotoxicity.

<p>A. Neutralization of TNF-α or TGF-β1 by a blocking antibody reduced MNU-induced clonogenic capacity under 37°C and 28°C condition. B. Neutralization of TNF-α abrogated MNU-induced cytotoxicity but neutralization of TGF-β1 promoted MNU-induced cytotoxicity under 37°C and 28°C condition. Data were expressed as mean ± SD. One asterisk (<b>*</b>)<0.001 as compared to MNU control under the same condition (n = 5).</p