Rapid and high-precision displacement sensing based on the multiple mode dip areas in a SNAP microresonator.

Whispering gallery mode (WGM) microresonators offer significant potential for precise displacement measurement owing to their compact size, ultrahigh sensitivity, and rapid response. However, conventional WGM displacement sensors are prone to noise interference, resulting in accuracy loss, while the demodulation process for displacement often exhibits prolonged duration. To address these limitations, this study proposes a rapid and high-precision displacement sensing method based on the dip areas of multiple resonant modes in a surface nanoscale axial photonics microresonator. By employing a neural network to fit the nonlinear relationship between displacement and the areas of multiple resonant dips, we achieve displacement prediction with an accuracy better than 0.03 µm over a range of 200 µm. In comparison to alternative sensing approaches, this method exhibits resilience to temperature variations, and its sensing performance remains comparable to that in a noise-free environment as long as the signal-to-noise ratio is greater than 25 dB. Furthermore, the extraction of the dip area enables significantly enhanced speed in displacement measurement, providing an effective solution for achieving rapid and highly accurate displacement sensing.

Study on the Expression Significance of Mb, BChE and cTnI in Myocardial Infarction and Their Relationship with Prognosis.

Objective: Circulating biomarkers can be used as effective prediction tools for AMI diagnosis and prognosis, but their prediction efficiency is limited and still needs to be explored. The study aimed to investigate the changes of myocardial troponin I (cTn I), myoglobin (Mb), and butyryl cholinesterase (BChE) levels in patients with acute myocardial infarction (AMI) and its clinical predictive efficacy. Methods: In this prospective cohort study, fifty patients with AMI who received PCI (AMI group) and 50 healthy subjects who underwent physical examination (reference group) during the same period were included. According to the occurrence of short-term major adverse cardiovascular events (MACE) during 6-month follow-up, they were divided into MACE group and non-MACE group . The difference of Mb, BChE, and cTnI levels was compared, and the ROC curve was drawn to analyze the prediction efficiency. Results: Compared with the reference group or non-MACE group, Mb and cTnI significantly increased and BChE significantly decreased inAMI group and MACE group, respectively (P < .05). The AUC of Mb, cTnI and BChE in diagnosing AMI occurrence and prognosis were all > 0.75, and the sensitivity and specificity were all > 85.00%. cTnI, Mb and BChE have good diagnostic efficacy in disease occurrence and prognosis evaluation of AMI patients. Conclusions: High expression of Mb and cTnI and low expression of BChE can increase the risk of AMI incidence and MACE occurrence and have high diagnostic efficacy, which can be used as sensitive factors in clinical AMI diagnosis and evaluation. Thess provided a theoretical foundation for AMI diagnosis and MACE preventing in AMI patients.

Displacement sensing in a multimode SNAP microcavity by an artificial neural network.

Benefiting from the coupling between the Surface Nanoscale Axial Photonics (SNAP) microcavity and the waveguide, i.e., influenced by their abrupt field overlap, multiple axial modes in the transmission spectrum form a functional relationship with the coupling position, thus enabling displacement sensing. However, this functional relationship is complex and nonlinear, which is difficult to be fitted using analytical methods. We introduce a back-propagation neural network (BPNN) to model this functional relationship. The numerical results show that the multimode sensing scheme has great potential for practical large-range, high-precision displacement sensing platforms compared with the single-mode sensing based on the whispering gallery mode (WGM) resonators.

Metformin and the risk of dementia based on an analysis of 396,332 participants.

Background: AMPK has attracted widespread interest as a potential therapeutic target for age-related diseases, given its key role in controlling energy homeostasis. Metformin (Met) has historically been used to treat Type 2 diabetes and has been shown to counteract age-related diseases. However, studies regarding the relationship between Met and a variety of age-related classifications of cognitive decline have reported mixed findings. Objective: To assess the potential effect of Met on the onset of dementia and discuss the possible biological mechanisms involved. Methods: This study was registered in the PROSPERO database (CRD420201251468). PubMed, Embase, and Cochrane Library were searched from inception to 25 May 2021, for population-based cohort studies. Effect estimates with 95% confidence intervals (CIs) were pooled using the random-effects model. Meta-regression and subgroup analyses were performed to explore sources of heterogeneity and the stability of the results. Results: Fourteen population-based cohort studies (17 individual comparisons) involving 396,332 participants were identified. Meta-analysis showed that Met exposure was significantly associated with reduced risk of all subtypes of dementias [relative risk (RR) = 0.79, 95% CI = 0.68-0.91; p < 0.001]. Conversely, no significant reduction in risk was observed for those who received Met monotherapy at the onset of vascular dementia (VD), Parkinson's disease (PD), and Alzheimer's disease (AD). The effect was more prominent in patients who had long-term Met exposure (⩾4 years) (RR = 0.38, 95% CI = 0.32-0.46; p < 0.001), while no such significant effect was found with short-term Met exposure (1-2 years) (RR = 1.20, 95% CI = 0.87-1.66; p < 0.001). Moreover, no association was observed for Met exposure in participants of European descent (RR = 1.01, 95% CI = 0.66-1.54; p = 0.003) compared with those from other countries. Conclusion: Based on the evidence from population-based cohort studies, our findings suggest that the AMPK activator, Met, is a potential geroprotective agent for dementias, particularly among long-term Met users. Due to the significant heterogeneity among the included studies, we should interpret the results with caution.

Progress in diagnosis of bone metastasis of prostate cancer. / å‰åˆ—è ºç™Œéª¨è½¬ç§»è¯Šæ–­çš„ç ”ç©¶è¿›å±•.

The diagnosis of bone metastasis of prostate cancer (PC) is of great significance to the treatment and prognosis of patients with PC.Bone scan is the most commonly used in the early diagnosis of bone metastasis, but its specificity is low and there is a high false positive.In recent years, with the in-depth study of the application of CT, MRI, emission computed tomography (ECT), positron emission computed tomography/computed tomography (PET/CT) and deep learning algorithm-convolutional neural networks (CNN) in the diagnosis of bone metastasis, the combined application of various auxiliary parameters in the diagnosis of bone metastasis has significantly been improved. The therapeutic effect of PC patients with bone metastasis can also be evaluated, which is expected to achieve the treatment of bone metastasis as well as diagnosis. By systematically expounding the research progress of the above-mentioned techniques in the diagnosis of bone metastasis, it can provide clinicians with new methods for the diagnosis of bone metastasis and improve the diagnostic efficiency for bone metastasis.

Simulation and Optimization of SNAP-Taper Coupling System in Displacement Sensing.

Sensing applications based on whispering gallery mode (WGM) microcavities have attracted extensive attention recently, especially in displacement sensing applications. However, the traditional displacement sensing scheme based on shift in a single resonance wavelength, has a lot of drawbacks. Herein, a novel displacement sensing scheme based on the surface nanoscale axial photonics (SNAP) is proposed to achieve a wide range and high-resolution displacement sensor through analyzing the transmittance of multiple axial modes. By analyzing the surface plot of the resonance spectrum with different coupling positions, the ideal coupling parameters and ERV for displacement sensing are obtained. In the following, displacement sensing with high sensitivity and a wide range is theoretically realized through adjusting the sensitivity threshold and the number of modes. Finally, we present our views on the current challenges and the future development of the displacement sensing based on an SNAP resonator. We believe that a comprehensive understanding on this sensing scheme would significantly contribute to the advancement of the SNAP resonator for a broad range of applications.

High spectral purity electromagnetically induced transparency-based microwave optoelectronic oscillator with a quasi-cylindrical microcavity.

High spectral purity microwave oscillators are widely exploited in science and military areas including communication, radar, and navigation. Here, we theoretically analyze and experimentally observe the application of tunable electromagnetically induced transparency (EIT) effect generated within a single quasi-cylindrical microresonator (QCMR) to a high spectral purity microwave optoelectronic oscillator (OEO). Stable single-frequency microwave oscillation with phase noise of -123 dBc/Hz at 10 kHz offset from ~5 GHz carrier and -135 dBc/Hz at 100 kHz offset is demonstrated without using any narrow-band RF filters. Moreover, we evaluate the impact of laser-mode locking state, quality factor as well as spectral lineshapes of the EIT resonance, laser coupling efficiency, and three configurations of optical energy storage elements on the spectral purity of the oscillator, so as to improve its phase noise and stability performances. Extending the concept of EIT to a microwave generator opens a promising avenue towards compact low-phase-noise oscillator systems for emerging mass applications.

Dispersion engineering of a microsphere via multi-layer coating.

Controlling dispersion of a whispering gallery mode resonator is of critical importance for many nonlinear applications, such as frequency comb generation, parametric oscillators, Raman lasers, stimulated Brillouin lasers, and ultrafast optics. Here, we show by numerical and theoretical modeling that dispersion can be strongly engineered in a three-layer-coated microsphere of high, low, and high refractive indices (RIs). We investigate the impact of the coating thickness, the gap between the two high-RI layers, the surrounding medium, and the coating materials on the group-velocity dispersion and discover that the dispersion is controllable over a broad range in both normal and anomalous dispersion regimes. Our approach provides dispersion engineering flexibility in any axisymmetric resonator with a three-layer-coating structure.

Long non-coding RNA MEG3 inhibits microRNA-125a-5p expression and induces immune imbalance of Treg/Th17 in immune thrombocytopenic purpura.

BACKGROUND: The imbalance of Treg/Th17 cells is an important pathogenic factor for immune thrombocytopenic purpura (ITP). We previously reported miR-125a-5p targeted CXCL13 and participated in the process of ITP. In the present study, the role of miR-125a-5p in regulating Treg/Th17 ratio and its potential molecular mechanism were investigated. METHOD: A total of 30 adults with ITP and 30 healthy subjects were included. MEG3 expression in peripheral blood derived CD4+ T cells from ITP patients and healthy subjects were detected by real-time PCR. In vitro experiments, the effects of inhibiting or overexpressing MEG3 on the expression of miR-125a-5p, Foxp3 and ROTγt in CD4+ T cells were investigated. RESULTS: MEG3 expression was increased in CD4+ T cells of patients with ITP. Dexamethasone decreased MEG3 expression level of CD4+ T cells in vitro. MEG3 directly interacted with miR-125a-5p and MEG3 overexpression inhibited miR-125a-5p expression in CD4+ T cells exposed to dexamethasone. MEG3 down-regulation or miR-125a-5p overexpression promoted Foxp3 expression and inhibited RORγt expression. CONCLUSION: MEG3 interacted with miR-125a-5p and inhibited its expression, and MEG3/miR-125a-5p contributed to induce immune imbalance of Treg/Th17 in ITP.

PEBP4 silencing inhibits hypoxia-induced epithelial-to-mesenchymal transition in prostate cancer cells.

Hypoxia induced epithelial-to-mesenchymal transition (EMT) to facilitate the tumor biology. Phosphatidylethanolamine-binding protein 4 (PEBP4) is a member of the PEBP family and has been reported to be upregulated in various cancer types. The definite function of PEBP4 in regulating the EMT of prostate cancer, however, is still unclear. Here, we examined the functional role of PEBP4 and the underlying molecular mechanisms in hypoxia-induced EMT in prostate cancer cells. Our results showed that PEBP4 mRNA and protein expression was markedly increased in the human prostate cancer tissues and cell lines. Knockdown of PEBP4 significantly inhibited hypoxia-induced migration/invasion and EMT program. Furthermore, knockdown of PEBP4 prevented hypoxia-induced the expression of p-Akt and p-mTOR in prostate cancer cells. Taken together, this study reported here provided evidence that knockdown of PEBP4 inhibited hypoxia-induced EMT in prostate cancer cells. Our study uncovered a novel role for PEBP4 in prostate cancer progression, which might support the potential for PEBP4 targeting in prostate cancer therapy.

Stable controlling of electromagnetically induced transparency-like in a single quasi-cylindrical microresonator.

We experimentally and theoretically demonstrate electromagnetically induced transparency (EIT)-like and Fano resonance in a single quasi-cylindrical microresonator (QCMR). Stable controlling of the EIT and Fano resonance lineshapes can be achieved by vertically moving the resonator along its axis while in touch with the tapered fiber. Moreover, by horizontally scanning the coupling point along the tapered fiber, asymmetric Fano resonances of the transmission spectra are observed and can be engineered to vary periodically. Interestingly, the two different kinds of mechanisms that induce the Fano or EIT resonances can work on the same mode simultaneously. Our device offers a stable platform for controlling the EIT and Fano resonances and holds unique potential in all-optical switching, quantum information processing and sensitivity-enhanced sensing applications.

Selective excitation of axial modes in a high-Q microcylindrical resonator for controlled and robust coupling.

We investigate selective excitation of localized axial modes in a high-Q microcylindrical resonator experimentally, numerically, and theoretically. The resonator is fabricated using a standard fusion splicer, and the characteristic resonance spectra are acquired by using a tapered fiber coupled at different positions along the microcylinder. The spatial and spectral mode properties are analyzed with our numerical and theoretical model, which are in good agreement with the experimental results. Moreover, controlled and robust coupling is experimentally demonstrated by vertically moving the resonator while keeping it in contact with the tapered fiber. Our microcylindrical resonator combines clean and nearly equidistant spectra, a high quality factor up to 3.1×10(7), a large mode volume, and a more favorable frequency spacing of ∼3.91 GHz, offering unique potential in sensors, microlasers, optical filters, group delay lines, and especially some applied fields that require tuning.

MicroRNA-125-5p targeted CXCL13: a potential biomarker associated with immune thrombocytopenia.

BACKGROUND: Immune thrombocytopenia (ITP) is an acquired and autoimmune disease of adults and children characterized by decreased platelet production. CXC chemokine ligand-13 (CXCL13) participates in multiple immunological responses. However, it is still unknown the relationship between CXCL13 and ITP. METHODS: Plasma CXCL13 was detected in ITP (n = 30) children. CD4+ T cells was isolated from peripheral blood mononuclear cells (PBMCs) from healthy volunteers. Treated CD4+ T cells with dexamethasone and/or miR-125-5p mimic/inhibitor, to observe the regulation of CXCL13. RESULTS: Compared with controls, ITP children had elevated plasma CXCL13, the concentration of which was reduced after treatment. In vitro, dexamethasone decreased CXCL13 level in in dose- dependent and in time-dependent manner. MiR-125-5p mimic decreased CXCL13 level and miR-125-5p inhibitor increased CXCL13 level in CD4+ T cells. CXCL13 was implied to be target gene of miR-125-5p. MiR-125-5p inhibitor also canceled dexamethasone induced decrease of CXCL13. CONCLUSION: CXCL13 is the target gene of miR-125-5p, which is possibly involved in the pathological process of ITP.

Packaged microsphere-taper coupling system with a high Q factor.

A novel packaged microsphere-taper coupling system which consists of a glass tube and two glass plates is proposed and demonstrated in this paper. We analyze the impact of the microsphere distortion on the resonant spectrum and it is observed that a very high quality factor (Q) up to 1.08×10(8) can be achieved by optimizing the microsphere position and orientation relative to the fiber taper. The maintenance of Q and a stable spectrum are realized by placing the packaged structure in a sealed organic glass box. Furthermore, to verify the practicability of the sealed device, thermal sensing experiments are carried out, which indicates the excellent convenience of the device with a resolution of 1.12×10(-4)°C. The portability and robustness of the packaged structure make it strikingly attractive and illustrate its potential in practical microcavity sensors and lasers.

[Expressions of transforming growth factor-beta(1) and Smad4 in rat models of chronic nonbacterial prostatitis and their clinical significance].

OBJECTIVE: To investigate the expressions of transforming growth factor-beta(1) and Smad4 in the prostatic tissue of rat models of chronic nonbacterial prostatitis (CNP), and to explore the mechanisms of CNP and its fibrosis. METHODS: Sixty 6-month-old SD rats were randomly allocated into three groups of equal number: normal control, 30 d CNP model and 45 d CNP model, the models made by castration + high-dose intramuscular injection of estradiol benzoate. The expressions of TGF-beta1 and Smad4 in the prostatic tissue were detected by immunohistochemistry and Western blot. RESULTS: Compared with the normal controls, the 30 d and 45 d CNP rat models showed a significantly increased expression of TGF-beta1 and decreased expression of Smad4 (P < 0.05), even more significantly in the 45 d than in the 30 d group. And the expression of TGF-beta1 was negatively correlated with that of Smad4 in the CNP rat models. CONCLUSION: TGF-beta1 and Smad4 may be involved in the pathogenesis of CNP, and prostatic fibrosis may make the condition difficult to cure.

[Genetic detection and analysis of the VHL gene in patients with sporadic pheochromocytoma].

OBJECTIVE: To carry out a genetic detection and analysis of Von Hippel-Lindau (VHL) gene in Chinese patients with sporadic pheochromocytoma. METHODS: DNA samples were extracted from peripheral blood cells and fresh pheochromocytoma specimens from 41 patients with sporadic pheochromocytoma were assayed by polymerase chain reaction and direct sequencing. The DNA samples of 50 healthy volunteers were extracted from peripheral blood as a control. The PCR products of exon 1, exon 2 and exon 3 were used for molecular analysis of the VHL gene. The genetic detection of family members of VHL gene mutations was also performed. RESULTS: One of mutations was located at nucleotide 572 (G-->C) in exon 2, presenting a codon 120 from arginine (R) to threonine (T). Tow small insertions were locatated at nucleotide 623T (TTTGTtG) in exon 2, leading to a frameshift mutation. There were also three carriers of G572C and three carriers of 623T (TTTGTtG) in family members of the three cases. CONCLUSION: There are some Chinese patients with sporadic pheochromocytoma with tumorigenic VHL gene mutations. It is recommended to use the genetic detection and analysis of VHL gene as a routine examination for patients with sporadic pheoehromoeytoma under the age of 50 years with questionable family history. The genetic detection and analysis of VHL gene may be useful as a marker for the diagnosis of hereditary pheochromocytoma.

[Mutation screening of VHL gene in a Chinese family with nonsyndromic pheochromocytoma].

OBJECTIVE: To detect the VHL gene mutations in a Chinese family with nonsyndromic pheochromocytoma. METHODS: Mutations of VHL gene were detected in a Chinese family with nonsyndromic pheochromocytoma. Five patients and fifteen relatives were involved in this study. Peripheral blood was collected and total genomic DNA was prepared for polymerase chain reaction (PCR). PCR products of all the three exons of VHL gene were purified and a direct gene sequence analysis was performed. RESULTS: All the five patients presented a codon 125 from Histidine (H) to Proline (P) change at nucleotide 587 (A --> C) in exon 2. Seven members of fifteen relatives were carriers with the same VHL gene mutation. Two carriers were detected with bilateral adrenal tumors and right renal cyst respectively by ultrasonic inspection. CONCLUSION: The novel VHL gene mutation detected in this kindred may be the causative gene. Genetic test can detect the carriers in an early period. It is recommended as a routine method of genetic test in nonsyndromic pheochromocytoma patients.