The influence of preoperative urodynamic parameters on clinical results in patients with benign prostatic hyperplasia after transurethral resection of the prostate.

PURPOSE: To identify the urodynamic parameters affecting the clinical outcomes of transurethral resection of the prostate(TURP) surgery for patients with benign prostatic hyperplasia(BPH) by multifactor analysis and establish a regression model with diagnostic values. METHODS: The medical records of patients who underwent TURP surgery for BPH between December 2018 and September 2021 were collected from the urology department of the Second Affiliated Hospital of Kunming Medical University, Kunming, China. The patients' clinical data and urodynamic parameters were collected before surgery. The urodynamic parameters affecting surgical efficacy were identified by multifactor analysis, and a regression model with diagnostic values was established and evaluated. RESULTS: A total of 201 patients underwent TURP, of whom 144 had complete preoperative urodynamic data. Each urodynamic factor was subjected to multifactor analysis, and the bladder contractility index (BCI), bladder outflow obstruction index (BOOI), bladder residual urine, and bladder compliance (BC) were found to be independent influence factors on the efficacy of TURP in patients with BPH. The diagnostic value of the regression model was analyzed by receiver operating characteristics (ROC) analysis, and it was found that the AUC = 0.939 (95% CI 0.886-0.972), for which the sensitivity and specificity were 95.19% and 80%, respectively. CONCLUSIONS: The regression model had high diagnostic sensitivity and specificity in predicting the efficacy of surgery, and the diagnostic value was higher than that of individual urodynamic factors. Therefore, BCI, BOOI, bladder residual urine, and BC should be considered as independent influence factors on the efficacy of TURP surgery for BPH.

Microwave photonic radar system with improved SNR performance utilizing optical resonant amplification and random Fourier coefficient waveforms.

A microwave photonic (MWP) radar system with improved signal-to-noise ratio (SNR) performance is proposed and experimentally demonstrated. By improving the SNR of echoes through properly designed radar waveforms and resonant amplification in the optical domain, the proposed radar system can detect and image weak targets that were previously hidden in noise. Echoes with a common low-level SNR obtain high optical gain and the in-band noise is suppressed during resonant amplification. The designed radar waveforms, based on random Fourier coefficients, reduce the effect of optical nonlinearity while providing reconfigurable waveform performance parameters for different scenarios. A series of experiments are developed to verify the feasibility of the SNR improvement of the proposed system. Experimental results show a maximum SNR improvement of 3.6 dB with an optical gain of 28.6 dB for the proposed waveforms over a wide input SNR range. From a comparison with linear frequency modulated signals in microwave imaging of rotating targets, significant quality enhancement is observed. The results confirm the ability of the proposed system to improve SNR performance of MWP radars and its great application potential in SNR-sensitive scenarios.

Investigation of signal-to-noise ratio performance of microwave photonic links enhanced by optical injection locking and channelized spectrum stitching.

A signal-to-noise ratio (SNR) improvement method for microwave photonic (MWP) links enhanced by optical injection locking (OIL) and channelized spectrum stitching (CSS) is investigated and experimentally demonstrated. By exploiting the resonant amplification characteristics of OIL, both optical gain and in-band noise suppression of the input radio frequency signal can be achieved. The injection bandwidth is channelized to further suppress noise during OIL, and the input signal can be well reconstructed by spectrum stitching in the digital domain. Experimental results show that the optimal improvement in SNR of 3.6 dB is achieved for linear frequency modulated signals and at least an additional improvement of 7.2 dB can be obtained by adopting CSS. Other broadband signals for radar and communication are used to further verify the ability to improve SNR. The potential for application scenarios with large operating bandwidth and high optical gain is also demonstrated.

Scalable distributed microwave photonic MIMO radar based on a bidirectional ring network.

A scalable distributed microwave photonic multiple-input-multiple-output (MIMO) radar is proposed based on a bidirectional ring network. The network is constructed with a fiber ring on which a local node and several remote nodes are distributed. In the local node, radar signals are generated over different optical wavelengths based on external modulation. Employing wavelength-division multiplexing, the radar signals are sent to remote nodes through the fiber ring. In different remote nodes, radar signals modulated on corresponding wavelength are utilized for transmitting or photonic de-chirp processing. Benefiting from the bidirectional ring network, the proposed radar is suitable for large-scale distribution. Together with the pluggable remote nodes, the scalability of the radar is enhanced. A proof-of-concept experiment is demonstrated to verify the feasibility of the system. Measurements of two-dimensional position and velocity of targets are realized. The position error and velocity error are better than 8 cm and 0.20 m/s respectively.

Microwave photonic de-chirp receiver for breaking the detection range swath limitation.

A novel microwave photonics-based de-chirp radar receiver which breaks the limitation of the detection range swath is proposed and demonstrated. In the proposed receiver, a multi-channel time-division photonics de-chirp processing is implemented to increase the detection range swath. A linear frequency modulated pulse train is sent to multiple reception channels and temporally delayed in the optical domain to form reference signal replicas, enabling time-division photonics-de-chirp processing with echoes reflected from different distance regions so that the total detection range swath is increased and determined by the number of reference replicas. Hardware-in-the-loop simulation experiments are demonstrated and an inverse synthetic aperture 2D imaging is carried out, showing that the MWP radar with the proposed photonics de-chirp receiver is capable of achieving a detection range swath of 13km which is 20 times larger than that when employing a conventional de-chirp receiver with the same parameters.

Novel RF-source-free reconfigurable microwave photonic radar.

A novel reconfigurable microwave photonic (MWP) radar has been proposed and experimentally demonstrated. At a transmitting end, a microwave signal with a large bandwidth and ultra-low phase noise is generated by a Fourier domain mode locking optoelectronic oscillator. At a receiving end, photonics-based de-chirp processing is implemented by phase-modulating light waves in a dual-drive Mach-Zehnder modulator and mixing the modulated light waves at a photodetector. Without the requirement of external RF sources, the developed photonics-assisted programmable radar is capable of generating and processing microwave signals with adjustable format, bandwidth and central frequency. The proposed radar working from X to Ku band with an instantaneous bandwidth of 2 GHz is demonstrated. The reconfiguration of the radar is theoretically analyzed. The tunability of radar bandwidth and central frequency is investigated. Microwave imaging of a pair of trihedral corner reflectors based on the developed MWP radar is achieved.

Channelized photonic-assisted deramp receiver with an extended detection distance along the range direction for LFM-CW radars.

A novel photonic-assisted deramp receiver extends detection distance along range direction of linearly-frequency-modulated continuous wave (LFM-CW) radars is proposed. A dual-polarization quadrature phase shift keying (DP-QPSK) modulator is used to modulate an optical frequency-comb (OFC) to generate orthogonally polarized optical signals. Then the orthogonally polarized optical signals are coherently detected with an optical local oscillator (OLO), which is generated by modulating the other OFC with the RF-reference signal on a null-biased Mach-Zehnder modulator (MZM). At the output of each detection unit, beating results can be recovered using a digital signal processing algorithm. By stitching the beating results of several paralleled detection units, the deramp signal corresponded to an extended range distance can be recovered. The proposed technique is experimentally evaluated through both simulated echoes and real echoes of two static trihedral corner reflectors (TCRs) distributed along range direction.

Wide-band RF receiver based on dual-OFC-based photonic channelization and spectrum stitching technique.

A novel wide-band RF receiver based on a dual-OFC-based channelization and spectrum stitching technique is proposed and demonstrated experimentally. In the scheme, a dual-OFC-based channelizer is utilized as the front-end to slice the RF signals into multiple channels. In the back-end, through the channel estimation and spectrum stitching, the received signals can be well reconstructed in the digital domain. A proof-of-concept experiment is performed, in which signals with 3 GHz bandwidths are sliced and reconstructed using the proposed receiver with a normalized mean squared error (NMSE) of 7.9×10-3. The performances of the reconstructed signals on pulse compression are also demonstrated to evaluate the potential of the proposed technique in practical applications.

Reconfigurable multi-band microwave photonic radar transmitter with a wide operating frequency range.

A photonics-assisted multi-band radar transmitter operating in a wide frequency range has been proposed and experimentally demonstrated. The multi-band radar transmitter incorporates a tunable optoelectronic oscillator (OEO), a low-frequency RF source and a microwave photonic frequency-converting link. In the frequency-converting link, a single tone with ultra-low phase noise and a low-frequency narrow-band RF signal that are generated respectively by the OEO and the RF source, are mixed, frequency converted and bandwidth multiplied to generate multi-band transmission signals. The central frequency, bandwidth and modulation format of transmission signals are reconfigurable. A multi-band radar transmitter with an instantaneous bandwidth of 1.6 GHz is developed. The frequency range of the multi-band radar transmitter covers six bands (from S to Ka), and a moving target detection experiment verifies that the proposed system has potential in multifunctional radar applications.

Correlation between gastric carcinoma and ZAC gene-associated microsatellite instability and loss of heterozygosity.

The present study explored the association between loss of heterozygosity (LOH) or microsatellite instability (MSI) of the zinc finger regulator of apoptosis and cell-cycle arrest (ZAC) gene and the clinicopathological factors of gastric cancer. Samples of cancer and cancer-adjacent normal tissue from 30 patients with gastric cancer were collected. The genomic DNA was extracted from each and amplified with primers specific to ZAC microsatellite mutations, then run on a polyacrylamide gel for analysis. The CA197 microsatellite locus exhibited LOH in cancer sample 4. There was LOH in the 15AAAG locus in cancer sample 27 and cancer-adjacent tissue 23, and MSI at 15AAAG in cancer-adjacent tissue 27. There was MSI at the D6S1703 microsatellite locus in cancer-adjacent tissue 28. There was no LOH or MSI in the CA340 microsatellite locus in the gastric cancer or adjacent tissues analyzed. Thus, the frequency of LOH or MSI at ZAC gene-associated microsatellite loci for all patients was 13.3% (4/30). The present study has demonstrated that LOH and MSI events may contribute to the downregulation of ZAC; however, it is unlikely to be the primary cause, as it was only identified in 13.3% of cases.

Influence of extract of Ginkgo biloba leaves tablets on the aquaporin-1 expression in isolated lung ischemia reperfusion.

BACKGROUND: The extract of Ginkgo biloba leaves tablets, ginaton, is widely used in treating ischemic cerebrovascular disease in the clinic. This study aimed to investigate the expression of aquaporin-1 (AQP-1) in rat lung with ischemia/reperfusion injury after pretreatment with ginaton, and whether the pretreatment with ginaton reduces the acute lung injury caused by ischemia/reperfusion injury. METHODS: Adult Wistar rats were divided into two groups. Some rats were used as donors (n = 20), the others as recipients (n = 20). Left lungs of donor rats were used for the isolated lung reperfusion model, which perfused only with low potassium dextran (LPD) solution as group A (n = 10); the others were pretreated with ginaton before reperfusion as group C (n = 10). Right lung of donor rat without any treatment was used as a control group (group B and group D, n = 10 for each group). After the model was established, the expression of AQP-1 in the lung tissues was examined by immunohistochemistry, Western blotting, and reverse transcriptase-polymerase chain reaction. RESULTS: Immunohistochemical examination revealed that AQP-1 was expressed in endothelia. Immunoblotting demonstrated that the relative gray values of AQP-1 protein in groups A and C were 0.65±0.06, 0.88±0.11, respectively. The relative gray values of the mRNA expression in groups A and C were 0.30±0.08, 0.49±0.11, respectively. The expression of AQP-1 protein and mRNA in group C was significantly higher than in group A (P < 0. 05). CONCLUSION: The pretreatment with ginaton can reduce the acute lung injury caused by ischemia/reperfusion.

[Detection of the expression level of S100C gene in lung cancer tissue by RT-PCR and construction and identification of prokaryotic expression vector].

OBJECTIVE: To analyze the expression level of S100C gene in lung cancer tissue and to construct prokaryotic expression vector pET30a-S100C in order to select fusion antibody in further study. METHODS: mRNA expression level of S100C gene in lung cancer tissue and ambient tissue in 26 cases was detected by RT-PCR with beta-actin as references. The full-length cDNA of S100C was cloned by RT-PCR. The amplified DNA fragments were ligated into pET30a vector and then transformed into E. coli stain JM109. The positive clones were screened out and indentified. RESULTS: The expression level of S100C in lung cancer tissue was lower than that in ambient tissue. The difference between the two groups was statistically significant (P < 0.05). The prokaryotic expression vector of S100C was successfully constructed. The sequence homogenuity was up to 100%. CONCLUSION: The down-regulation expression of S100C gene probably takes important part in the carcinogenisis of lung cancer.

[Detection of the expression level of S100C gene in lung cancer tissue by RT-PCR and construction and identification of prokaryotic expression vector].

OBJECTIVE: To analyze the expression level of S100C gene in lung cancer tissue and to construct prokaryotic expression vector pET30a-S100C in order to select fusion antibody in further study. METHODS: mRNA expression level of S100C gene in lung cancer tissue and ambient tissue in 26 cases was detected by RT-PCR with p-actin as references. The full-length cDNA of S100C was cloned by RT-PCR. The amplified DNA fragments were ligated into pET30a vector and then transformed into E. coli stain JM109. The positive clones were screened out and indentified. RESULTS: The expression level of S100C in lung cancer tissue was lower than that in ambient tissue. The difference between the two groups was statistically significant (P < 0.05). The prokaryotic expression victor of S100C was successfully constructed. The sequence homogenuity was up to 100%. CONCLUSION: The down-regulation expression of S100C gene probably takes important part in the carcinogenisis of lung cancer.

Role of stress-activated MAP kinase P38 in cisplatin- and DTT-induced apoptosis of the esophageal carcinoma cell line Eca109.

AIM: To study the role of P38 kinase in esophageal cancer cell apoptosis induced by genotoxin, cisplatin and the unfolded protein response (UPR) inducer, dithiothreitol (DTT). METHODS: Esophageal carcinoma cell line Eca109 was cultured in RPMI 1640 medium to 70% confluency and treated with either cisplatin, DTT, or cisplatin plus DTT in the presence or absence of P38 inhibitor, SB203580. The untreated cells served as the control. The esophageal carcinoma cell apoptosis was detected by agarose gel DNA ladder analysis and quantified by flow cytometry. The P38 phosphorylation was detected by immunohistochemistry using antibodies specific to phosphorylated P38 protein. RESULTS: (1) Both cisplatin and DTT induced apoptosis in the esophageal cancer cell line Eca109 as shown by DNA ladder formation; (2) As detected by antibodies specific for the phosphorylated P38 protein (p-P38), both cisplatin and DTT treatments activated the stress-activated enzyme, MAP kinase P38. The number of positive cells was about 50% for the treatment groups, comparing to that of 10% for untreated group. DTT treatment, but not cisplatin treatment, induces nuclear localization of p-P38; (3) As measured by flow cytometry, inhibition of P38 activity by SB203580 blocks DTT- and cisplatin-induced apoptosis. The rates for DTT, cisplatin, and DTT plus cisplatin-induced apoptosis were 16.8%, 17.1%, and 21.4%, respectively. Addition of the SB compound during the incubation reduced the apoptotic rate to about 7.6% for all the treatment groups, suggesting that P38 activation is essential for cisplatin- and DTT-induced apoptosis in Eca109 cells. CONCLUSION: (1) Both DTT and cisplatin were able to induce apoptosis in esophageal cancer cell line Eca109; (2) P38 MAP kinase is essential for DTT- and cisplatin-induced apoptosis in Eca109 cells; (3) P38 activation may be the common signaling component relaying the multiple upstream signaling events to the downstream cell death program.