Measurement technology based on a Stokes parametric polarization system.

Structured light measurement systems often use polarization filters to reduce image interference from highly reflective areas. This method can be effective, but it may also reduce the brightness of specific areas, particularly overly dark portions, which can affect the accuracy of the measurement results. This paper proposes a measurement method for a polarization system based on Stokes parameters to solve the problem. After adjusting the polarization filter to angles of 0°, 45°, and 90°, the camera captures an image of the object and calculates the corresponding Stokes parameters to generate the expected polarization angle histogram. Then, based on the detailed information on the angle distribution, the accurate mathematical model is used to screen the interval, and the optimal polarization angle is determined by orthogonal processing while ensuring the signal-to-noise ratio and image quality. Finally, an image fusion technology synthesizes a set of fringe projection images with the preferred polarization angles. Experiments have shown that this new method effectively addresses the issue of interference in the highlighted region when using conventional polarization filters. Additionally, it significantly improves the quality of the fringe pattern. The polarization angle selection in the experimental process is made more rapid and accurate through the quantitative mathematical model calculation of the polarization angle, significantly improving the system's measurement efficiency.

Three-dimensional reconstruction of polarized ambient light separation in complex illumination.

In current research, it is still a hot topic for 3D reconstruction under complex illumination. This paper uses a polarization camera combined with a coding technique to propose a new 3D reconstruction method for polarized ambient light separation. Based on the polarization camera, a specific separation model is established to analyze the relationship between the polarization characteristics of polarized and natural light. Specular reflections were filtered first and then analyzed based on the stocks vector and muller matrix. A specific calculation process was used to calculate different polarization azimuths according to the polarization characteristics, and finally, the polarized light and ambient light were separated. The experimental results show that the use of this polarization camera approach reduces the number of steps required to rotate the polarizer multiple times. This not only reduces the shooting time but also improves the efficiency. Moreover, after separating the ambient light, polarization imaging suppresses the interference of the ambient light, which helps to highlight the complete point cloud image more clearly in the 3D reconstruction. The standard deviation of 3D reconstruction was improved to 0.1675 mm by using this method in indoor and outdoor experiments.

Andrographolide acts with dexamethasone to inhibit the growth of acute lymphoblastic leukemia CEM­C1 cells via the regulation of the autophagy­dependent PI3K/AKT/mTOR signaling pathway.

Acute lymphoblastic leukemia (ALL) is one of the most common malignant tumor types of the circulatory system. Dexamethasone (DEX) acts on the glucocorticoid (GC) receptor (GR) and is a first-line chemotherapy drug for ALL. However, long-term or high-dose applications of the drug can not only cause adverse reactions, such as osteoporosis and high blood pressure, but can also cause downregulation of GR and lead to drug resistance. In the present study, reverse transcription-quantitative PCR, western blotting and LysoTracker Red staining were used to observe the effects of DEX and andrographolide (AND; a botanical with antitumorigenic properties) combined treatment. It was found that AND enhanced the sensitivity of CEM-C1 cells, a GC-resistant cell line, to DEX, and synergistically upregulated GR both at the transcriptional and post-transcriptional level with DEX. The combination of AND with DEX synergistically alkalized lysosomal lumen and downregulated the expression of autophagy-related genes Beclin1 and microtubule-associated 1 protein light chain 3 (LC3), thereby inhibiting autophagy. Knocking down LC3 expression enhanced GR expression, suggesting that GR was regulated by autophagy. Furthermore, compared with the monotherapy group (AND or DEX in isolation), AND interacted with DEX to activate the autophagy-dependent PI3K/AKT/mTOR signaling pathway by enhancing the phosphorylation of PI3K, AKT and mTOR, thereby decreasing GR degradation and increasing the sensitivity of cells to GCs. In conclusion, the present study demonstrated that AND exhibited a synergistic anti-ALL effect with DEX via upregulation of GR, which was orchestrated by the autophagy-related PI3K/AKT/mTOR signaling pathway. The results of the present study therefore provided novel research avenues and strategies for the treatment of ALL.

Single-cell whole-genome sequencing, haplotype analysis in prenatal diagnosis of monogenic diseases.

Monogenic inherited diseases are common causes of congenital disabilities, leading to severe economic and mental burdens on affected families. In our previous study, we demonstrated the validity of cell-based noninvasive prenatal testing (cbNIPT) in prenatal diagnosis by single-cell targeted sequencing. The present research further explored the feasibility of single-cell whole-genome sequencing (WGS) and haplotype analysis of various monogenic diseases with cbNIPT. Four families were recruited: one with inherited deafness, one with hemophilia, one with large vestibular aqueduct syndrome (LVAS), and one with no disease. Circulating trophoblast cells (cTBs) were obtained from maternal blood and analyzed by single-cell 15X WGS. Haplotype analysis showed that CFC178 (deafness family), CFC616 (hemophilia family), and CFC111 (LVAS family) inherited haplotypes from paternal and/or maternal pathogenic loci. Amniotic fluid or fetal villi samples from the deafness and hemophilia families confirmed these results. WGS performed better than targeted sequencing in genome coverage, allele dropout (ADO), and false-positive (FP) ratios. Our findings suggest that cbNIPT by WGS and haplotype analysis have great potential for use in prenatally diagnosing various monogenic diseases.

Research Progress and Prospects of Autophagy in the Mechanism of Multidrug Resistance in Tumors.

Although the treatment of cancer has made great strides in clinical practice, its high morbidity and fatality rates remain a major threat to human health. Multidrug resistance (MDR) often appears in the process of tumor treatment, leading to tumor refractory and aggravating the risk of tumor recurrence. Therefore, antitumor MDR plays a key role in tumor chemotherapy. Autophagy is an important process for the turnover of intracellular materials, which is commonly seen in the treatment of sensitive and multidrug-resistant tumors, and it can play different roles in various types of MDR tumor cells and tissues. Autophagy plays a dual regulatory role in MDR tumors. On the one hand, autophagy can promote the formation of MDR in tumor cells, weaken the killing effect of chemotherapy drugs on tumor cells, and play a protective role in tumor survival. On the other hand, autophagy production in the cellular environment can kill MDR tumor cells, reverse tumor resistance and enhance the efficiency of chemotherapy drugs. Therefore, the regulation of autophagy to overcome MDR has become increasingly significant in tumor chemotherapy. In this article, we discussed and summarized the research progress of autophagy in MDR tumors, mainly involving the different characteristics of autophagy in MDR cancer cells.

Comparison of outcomes and side effects for neoadjuvant chemotherapy with weekly cisplatin and paclitaxel followed by chemoradiation vs. chemoradiation alone in stage IIB-IVA cervical cancer: study protocol for a randomized controlled trial.

BACKGROUND: Currently, the standard treatment for locally advanced cervical cancer is concurrent chemoradiation (CCRT). The effect of neoadjuvant chemotherapy in advanced cervical cancer is controversial. Studies have shown that the addition of a weekly regimen of neoadjuvant chemotherapy (NACT) followed by CCRT may be superior to a thrice-weekly regimen of NACT and CCRT. Among patients who had not received prior cisplatin, a cisplatin and paclitaxel (TP) regimen resulted in longer overall survival than other regimens. This study aims to investigate the feasibility, safety, and efficacy of NACT with weekly TP followed by CCRT. METHODS: This is a prospective, randomized, open-labeled, multicentered phase III study. Based on a 65% of 2-year disease-free survival (DFS) rate in the CCRT group and 80% of that in NACT followed by CCRT group, and on prerequisite conditions including an 8% loss to follow-up, a two-sided 5% of type I error probability, and an 80% of power, a total of 300 cases were required for enrollment. Patients with IIB-IVA cervical cancer will be randomly allocated in a 1:1 ratio to one of two intervention arms. In the study arm, patients will receive dose-dense cisplatin (40 mg/m2) and paclitaxel (60 mg/m2) weekly for 4 cycles followed by CCRT (45 Gy in 5 weeks concurrent with cisplatin 40 mg/m2 weekly) plus image-guided adaptive brachytherapy (IGBRT). In the control arm, patients will undergo CCRT treatment. The primary endpoint of the study is 2-year disease-free survival (DFS); the secondary endpoints are 5-year overall survival (OS) and disease-free survival (DFS), the response rate 3 months after treatment completion, grade III/IV adverse effects, and quality of life, and potential biomarkers for predicting treatment response will also be studied. DISCUSSION: The data gathered from the study will be used to determine whether NACT with weekly TP followed by CCRT may become an optimized treatment for locally advanced cervical cancer. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR1900025327. Registered on 24 August 2019. medresman.org.cn ChiCTR1900025326.

Circulating tumor DNA as a prognostic marker in high-risk endometrial cancer.

BACKGROUND: Currently, there is no reliable blood-based marker to track tumor recurrence in endometrial cancer (EC) patients. Liquid biopsies, specifically, circulating tumor DNA (ctDNA) analysis emerged as a way to monitor tumor metastasis. The objective of this study was to examine the feasibility of ctDNA in recurrence surveillance and prognostic evaluation of high-risk EC. METHODS: Tumor tissues from nine high-risk EC patients were collected during primary surgery and tumor DNA was subjected to next generation sequencing to obtain the initial mutation spectrum using a 78 cancer-associated gene panel. Baseline and serial post-operative plasma samples were collected and droplet digital PCR (ddPCR) assays for patient-specific mutations were developed to track the mutations in the ctDNA in serial plasma samples. Log-rank test was used to assess the association between detection of ctDNA before or after surgery and disease-free survival. RESULTS: Somatic mutations were identified in all of the cases. The most frequent mutated genes were PTEN, FAT4, ARID1A, TP53, ZFHX3, ATM, and FBXW7. For each patient, personalized ddPCR assays were designed for one-to-three high-frequent mutations. DdPCR analysis and tumor panel sequencing had a high level of agreement in the assessment of the mutant allele fractions in baseline tumor tissue DNA. CtDNA was detected in 67% (6 of 9) of baseline plasma samples, which was not predictive of disease-free survival (DFS). CtDNA was detected in serial post-operative plasma samples (ctDNA tracking) of 44% (4 of 9) of the patients, which predicted tumor relapse. The DFS was a median of 9 months (ctDNA detected) versus median DFS undefined (ctDNA not detected), with a hazard ratio of 17.43 (95% CI, 1.616-188.3). The sensitivity of post-operative ctDNA detection in estimating tumor relapse was 100% and specificity was 83.3%, which was superior to CA125 or HE4. CONCLUSIONS: Personalized ctDNA detection was effective and stable for high-risk EC. CtDNA tracking in post-operative plasma is valuable for predicting tumor recurrence.

[Determination of trace vitamin B2 by fluorimetry after aqueous two-phase extraction based on acetone and ethanol].

Small molecular water-miscible organic solvent, such as ethanol, acetone and acetonitrile, can be used to form aqueous two-phase system for extraction of analytes in the presence of salts. Just based on it, the acetone-salt-H2O and the ethanol-salt-H2O systems were developed for the determination of trace vitamin B2 coupled with fluorimetry after aqueous two-phase extraction. Various factors including the type and amount of salts and organic solvents, extraction time, coexistent substance, and pH were studied. The experimental results show that the extraction efficiencies of vitamin B2 in the acetone-salt-H2O and the ethanol-salt-H2O system were 97.6%-98.4% and 94.2%-95.5%, respectively, in one-step extraction. Under the optimal conditions, these two extraction techniques gave linear dynamic ranges of 1.5 x 10(-7)-3.5 x 10(-6) mol x L(-1) and 2..0 x 10(-7)-1.5 x 10(-6) mol x L(-1), with detection limits of 0.031 and 0.041 microg, respectively. Both techniques were applied directly to determination of vitamin B2 in pharmaceutical tablets and injections with satisfactory results. The relative errors were--1.8%-1.1% as compared with China pharmacopoeia and the relative standard deviations were 1.5%-2.2% for vitamin B2 in the above samples. Compared with conventional liquid-liquid extraction or solid-phase extraction, these methods have outstanding advantages such as simple operation, high extraction efficiency, little interference with analytes and low toxicity.

[Comparison of non-protected fluid room temperature phosphorescence and micellar-stabilized room temperature phosphorescence properties of indole-3-butyric acid].

For indole-3-butyric acid (IBA), the non-protected fluid room temperature phosphorescence (NP-RTP) and the fluid room temperature phosphorescence with polymeric dispersant polyethyleneglycol-200 (PEG-200), PEG-400 or non-ionic surfactant Tween-20, Tween-40, Tween-80, Tween-85, Brij35 and emulsifier OP as a medium have been studied in detail. When the surfactants or polymeric dispersants were added to the NP-RTP system, the profile of RTP spectrum was not changed, but the RTP intensity and the pre-irradiation time required to attain a stable RTP signal were increased. Whether the surfactants or polymeric dispersants were added to the system or not, no RTP signal was observed when TlNO3 was used as a heavy atom perturber (HAP), but intense RTP emissions were observed when KI was present as HAP. Recoveries of 95.2%-104% with relative standard deviations of 2.4%-4.0% were obtained in spiked water and soil samples.

Studies on properties and application of non-protected room temperature phosphorescence of propranolol.

A direct and simple non-protected room temperature phosphorimetry (NP-RTP) for determine propranolol, which using I- as a heavy atom perturber and sodium sulfite as a deoxygenator, has been developed. The phosphorescence peak wavelength maxima lambda(ex)/lambda(em) = 288/494, 522 nm. The analytical curve of propranolol gives a linear dynamic range of 8.0 x 10(-8)-2.0 x 10(-5) mol l(-1) and a detection limit of 3 x 10(-8) mol l(-1). The influence of I- concentration on RTP lifetime of propranolol was studied and the luminescence kinetic parameters were calculated. It is found that the relation between I- concentration (x) and RTP lifetime (tau) can be expressed as tau = 1.25e(-0.477x) and the rate constants of phosphorescence emission k(p) was 0.800 per ms. The method was applied directly to determination of propranolol in urine and drug tablets with a satisfactory result. The recoveries were 96.6-97.4% and the relative standard deviation was 2% for the 1.00 x 10(-6)-4.00 x 10(-6) mol l(-1) propranolol in spiked urine sample.

Complication of cesarean section: pregnancy on the cicatrix of a previous cesarean section.

OBJECTIVE: To probe into the clinical manifestation, diagnosis, as well as treatment of pregnancy on the cicatrix of a previous cesarean section at the uterine isthmus in the first trimester. METHODS: Analysis of 14 patients with pregnancy on the cicatrix of a previous cesarean section at the uterine isthmus in the first trimester was made after conservative treatment by drugs from January 1996 to December 1999. RESULTS: The 14 patients with a pregnancy on the cicatrix of a previous cesarean section at the uterine isthmus in the first trimester were painless, had slight vaginal bleeding, and concurrently had increased serum beta-subunit human chorionic gonadotropin (beta-HCG). Doppler ultrasonic examination revealed an obvious enlargement of the previous cesarean section cicatrix in the uterine isthmus, and found a gestational sac or mixed mass attached to the cicatrice, with a very thin myometrium between the gestational sac and bladder walls. Among the 14 patients, 12 patients had crystalline trichosanthes injected into the cervix, mifepristone taken orally, or methotrexate in the form of intramuscular injection. Following this procedure, their serum beta-HCG dropped to normal. The other 2 patients had a total hysterectomy. CONCLUSIONS: Pregnancy on the cicatrix of a previous cesarean section at the uterine isthmus in the first trimester is a complication of cesarean section. Early diagnosis and effective conservative treatment by drugs are instrumental in decreasing the potential occurrence of uterine rupture, which is also conducive to preserving the patient's future fertility.