Immobilized enzyme-based enzyme electrode biosensors, characterized by high sensitivity and efficiency, strong specificity, and compact size, demonstrate broad application prospects in life science research, disease diagnosis and monitoring, etc. Immobilization of enzyme is a critical step in determining the performance (stability, sensitivity, and reproducibility) of the biosensors. Random immobilization (physical adsorption, covalent cross-linking, etc.) can easily bring about problems, such as decreased enzyme activity and relatively unstable immobilization. Whereas, directional immobilization utilizing amino acid residue mutation, affinity peptide fusion, or nucleotide-specific binding to restrict the orientation of the enzymes provides new possibilities to solve the problems caused by random immobilization. In this paper, the principles, advantages and disadvantages and the application progress of enzyme electrode biosensors of different directional immobilization strategies for enzyme molecular sensing elements by specific amino acids (lysine, histidine, cysteine, unnatural amino acid) with functional groups introduced based on site-specific mutation, affinity peptides (gold binding peptides, carbon binding peptides, carbohydrate binding domains) fused through genetic engineering, and specific binding between nucleotides and target enzymes (proteins) were reviewed, and the application fields, advantages and limitations of various immobilized enzyme interface characterization techniques were discussed, hoping to provide theoretical and technical guidance for the creation of high-performance enzyme sensing elements and the manufacture of enzyme electrode sensors.

Objective: To evaluate the efficacy and safety of plasma exchange (PE) in thymoma-associated myasthenia gravis (MG), thereby to provide theoretical support for its application in the treatment of thymoma-associated MG. Methods: A total of 133 patients with thymoma-associated MG admitted from January 2018 to September 2024 were retrospectively analyzed. Patients were matched using propensity score to reduce selection bias, yielding 22 matched pairs for both PE group (n=22) and non-PE group (n=22). Patient characteristics including gender, age of disease onset, course of disease, history of thymoma resection, clinical absolute scores [clinical absolute scores (CAS) and clinical relative scores (CRS)], and synchronized immunotherapy regimen of the two groups were analyzed. The CAS scores before and after treatment were compared between the two groups, and the CRS was used to assess the treatment efficiency. Safety of the two treatment regimens were also compared. Continuous variables were compared using the t-test or ANOVA, while categorical data were compared by the chi-square test. Results: A total of 133 patients were included and divided into two groups according to whether they underwent plasma exchange treatment: the PE group (n=22) and the non-PE group (n=111). To exclude bias caused by large difference in the number of cases between the two groups, we performed propensity score matching. After matching, the number of cases in both groups was 22. There was no significant difference in baseline clinical characteristics between the two groups (P>0.05), including gender, age of onset, duration of disease course, history of thymectomy and baseline CAS score before treatment. Compared to the non-PE group, patients in the PE group showed more significant improvement in CAS score (5.09±1.95 vs 3.59±1.50, P<0.05) and a higher CRS score (75.00% vs 50.00%, P<0.001). Compared to the non-PE group, PE group had significantly longer ICU stay, longer hospital stay and higher hospitalization cost (P<0.05). There was no statistically significant difference in adverse events between the two groups during treatment (P>0.05). During long-term follow-up, both the PE and non-PE groups showed relatively low 1-, 3-, and 5-year recurrence rate, with no significant difference between the two groups (P>0.05). Conclusion: This study indicates that plasma exchange has clear value in the treatment of patients with thymoma-associated myasthenia gravis. It can not only significantly improve patients' muscle strength to alleviate motor dysfunction and enhance quality of life, but also does not significantly increase the incidence of adverse reactions. Therefore, it can be regarded as one of the preferred treatment options that achieve a "balance between efficacy and safety" for such patients, and provides an important basis for optimizing treatment strategies, improving prognosis, and promoting the application of subsequent treatment regimens.

Objective:To investigate the correlations of urinary adverse reactions with dose to the bladder and urethra during external pelvic irradiation for locally advanced cervical cancer.Methods:This study retrospectively collected relevant dosimetric parameters and urinary symptoms, such as frequent, urgent, and painful urination, from locally advanced cervical cancer patients treated with external pelvic irradiation in the Department of Oncology, Affiliated Hospital of Guizhou Medical University. The dosimetric parameters examined in this study included the maximum, minimum, and mean doses to bladder and urethra (i.e., Dmax, Dmin and Dmean), mean doses received in an area of 0.1, 1, and 2 cm 3 around the planning target volume, D0.1 cm 3, D1 cm 3, D2 cm 3, and percentages of irradiated volumes in the whole organ volume under doses of 5, 10, 15, 20, 25, 30, 35, 40, 45, 50 Gy, V5 Gy, V10 Gy, V15 Gy, V20 Gy, V25 Gy, V30 Gy, V35 Gy, V40 Gy, V45 Gy, V50 Gy. Then the correlations between urinary symptoms and these dosimetric parameters were analyzed using the independent-sample t-test and the Logistic regression model. Results:The median volumes of bladder and urethra were 294.8 and 4.71 cm 3, respectively. Patients were divided into two groups based on the median division. The univariate analysis showed that urethral Dmax, Dmin, Dmean, V5 Gy, V10 Gy, V15Gy, V20 Gy, V25 Gy, V30 Gy, V35 Gy, V40 Gy, V45 Gy and V50 Gy correlated with urinary complications ( t = 14.30, 21.65, 32.19, 33.36, 16.62, 17.91, 21.52, 20.11, 12.27, 37.25, 30.18, 36.24 and 21.98, P<0.05). The multivariate analysis further indicates that urethral D2 cm 3, V20 Gy, V40 Gy and Bladder V40 Gy, D1 cm 3, D2 cm 3 were independent predictors of grade 2 urinary adverse reactions ( P<0.05). Conclusions:This study reported the correlations of relevant dosimetric parameters of urethra with urinary toxicity during external pelvic irradiation. It holds that urethral D2 cm 3, V20 Gy and V40 Gy should be restricted to minimize the risks of grade 2 urinary complications.

Tropane alkaloids (TAs) are a class of anticholinergic drugs widely used in clinical practice and mainly extracted from plant, among which Atopa belladonna is the main commercial drug source. It is of great industrial value to obtain TAs in large quantities by plant metabolic engineering. In TAs pathway, cytochrome oxidase CYP82M3 catalyze the synthesis of tropinone and then tropinone reductase I (TRI) compete with TRII for tropinone to form tropine leading to the TAs synthesis (drainage). In this study, based on the "increasing flow and drainage" metabolic engineering strategy, two genes, namely HnCYP82M3 and DsTRI from Hyoscyamus niger and Datura stramonium, respectively, were overexpressed in the hair roots of A. belladonna, with a view to promote the TAs accumulation. The HnCYP82M3 gene was cloned from the root of H. niger, and it encoded amino acid with 91.7% sequence identity with AbCYP82M3 from A. belladonna. Overexpression of HnCYP82M3 alone did not affect the content of TAs in hair roots of A. belladonna, indicating that CYP82M3 was not a key enzyme in TAs biosynthesis. Simultaneous overexpression of HnCYP82M3 and DsTRI greatly promoted the accumulation of the three TAs, and the contents of hyoscyamine, anisodamine and scopolamine were 4.97 times, 2.83 times and 2.19 times that of the control, respectively, and the increase amplitude was greater than that of single overexpression of DsTRI. This study showed that the "increasing flow and drainage" strategy of enzyme genes co-expression at branch points was a promising metabolic engineering method to effectively improve the biosynthesis of TAs in A. belladonna, and laid a theoretical and technical foundation for the large-scale industrial acquisition of TAs.

AIM To establish a quantitative analysis of multi-components by single-marker(QAMS)method for the simultaneous content determination of gastrodin,parishin E,syringin,parishin B,parishin C,ferulic acid,parishin A,buddleoside,harpagoside and cinnamic acid in Tianma Toufengling Capsules.METHODS The analysis was performed on a 30℃thermostatic GL Science InertsilTM ODS-3 column(150 mm×4.6 mm,5 μm),with the mobile phase comprising of acetonitrile-0.1%phosphoric acid flowing at 1.0 mL/min in a gradient elution manner,and the detection wavelengths were set at 220,280 nm.Syringin was used as an internal standard to calculate the relative correction factors of the other nine constituents,after which the content determination was made.RESULTS Ten constituents showed good linear relationships within their own ranges(r≥0.999 7),whose average recoveries were 98.53%-102.22%with the RSDs of 1.26%-2.68%.The result obtained by QAMS approximated those obtained by external standard method.CONCLUSION This accurate and specific method can be used for the quality control of Tianma Toufengling Capsules.

AIM To study the chemical constituents from the leaves of Cyanocarya paliurus(Batalin)Iljinskaja and their α-glucosidase inhibitory activities.METHODS The 95%ethanol extract from the leaves of C.paliurus was isolated and purified by macroporous resin,silica gel,Sephadex LH-20,polyamide,C18 reversed-phase silica gel and semi-preparative HPLC,then the structures of obtained compounds were identified by physicochemical properties and spectral data.Their α-glucosidase inhibitory activities were evaluated by PNPG.RESULTS Fifteen compounds were isolated and identified as cyclopaloside C(1),cyclopaloside A(2),juglanosides E(3),vaccinin A(4),ent-murin A(5),kaempferol 3-O-α-L-rhamnopyranoside(6),kaempferol-3-O-β-D-glucopyranoside(7),kaempferol-3-O-β-D-glucuronide methyl ester(8),kaempferol-3-O-β-D-glucuronide ethyl ester(9),kaempferol-3-O-β-D-glucuronide butyl ester(10),quercetin-3-O-α-L-rhamnopyranoside(11)quercetin-3-O-β-D-glucopyranoside(12),quercetin-3-O-β-D-galactopyranoside(13),quercetin-3-O-β-D-glucuronide butyl ester(14),dihydrokaempferol(15).The IC50 value of total extracts ihibited α-glucosidase was(1.83±0.04)μg/mL,and the IC50 values of compounds 1,4-5 were(29.48±1.86),(0.50±0.07),(0.71±0.07)μmol/L,respectively.CONCLUSION Compound 1 is a new tetrahydronaphthalene glycoside.Compounds 4-5,8-10 and 14 are isolated from the leaves of C.paliurus for the first time.Compounds 4-5 are relatively rare flavonoid lignans with potential inhibitory activities against α-glucosidase.

Purpose::To assess the value of the driving pressure variation rate (ΔP%) in predicting the outcome of weaning from invasive mechanical ventilation in patients with acute respiratory distress syndrome.Methods::In this case-control study, a total of 35 patients with moderate-severe acute respiratory distress syndrome were admitted to the intensive care unit between January 2022 and December 2022 and received invasive mechanical ventilation for at least 48 h were enrolled. Patients were divided into successful weaning group and failed weaning group depending on whether they could be removed from ventilator support within 14 days. Outcome measures including driving pressure, PaO 2:FiO 2, and positive end-expiratory pressure, etc. were assessed every 24 h from day 0 to day 14 until successful weaning was achieved. The measurement data of non-normal distribution were presented as median (Q 1, Q 3), and the differences between groups were compared by Wilcoxon rank sum test. And categorical data use the Chi-square test or Fisher's exact test to compare. The predictive value of ΔP% in predicting the outcome of weaning from the ventilator was analyzed using receiver operating characteristic curves. Results::Of the total 35 patients included in the study, 17 were successful vs. 18 failed in weaning from a ventilator after 14 days of mechanical ventilation. The cut-off values of the median ΔP% measured by Operator 1 vs. Operator 2 in the first 4 days were ≥ 4.17% and 4.55%, respectively ( p < 0.001), with the area under curve of 0.804 (sensitivity of 88.2%, specificity of 64.7%) and 0.770 (sensitivity of 88.2%, specificity of 64.7%), respectively. There was a significant difference in mechanical ventilation duration between the successful weaning group and the failure weaning group (8 (6, 13) vs. 12 (7.5, 17.3), p = 0.043). The incidence of ventilator-associated pneumonia in the successful weaning group was significantly lower than in the failed weaning group (0.2‰ vs. 2.3‰, p = 0.001). There was a significant difference noted between these 2 groups in the 28-day mortality (11.8% vs. 66.7%, p = 0.003). Conclusion::The median ΔP% in the first 4 days of mechanical ventilation showed good predictive performance in predicting the outcome of weaning from mechanical ventilation within 14 days. Further study is needed to confirm this finding.

Objective:To investigate the accuracy of magnetic resonance imaging (MRI) cine sequences in determining the range of tumor motion in radiotherapy, providing a basis for the precise delineation of the target volume in motion for radiation therapy.Methods:A modified chest motion phantom was placed in a MRI scanner, and a water-filled sphere was used to simulate a tumor. True fast imaging with steady precession (TrueFISP) MRI cine sequences from Siemens were used to capture the two-dimensional motion images of the simulated tumor. The phantom experiments were divided into three modes: head-foot motion mode, rotation motion mode, and actual respiratory waveform mode. In the head-foot motion mode, respiratory motion period (3, 4, 5, 6, 7 and 8 s), amplitude (5, 10 and 15 mm), and respiratory waveform of the simulated tumor (sin and cos4) were set, resulting in a total of 36 motion combinations. In the rotation motion mode, a cos4 waveform was used for respiration, with respiratory periods of 3, 4, 5, 6, 7 and 8 s, head-foot motion set amplitudes of 5, 10 and 15 mm, and anterior-posterior (AP) and left-right (LR) motion set amplitudes in three combinations ([2.5, 2.5] mm, [2.5, 5.0] mm, [5.0, 5.0] mm), resulting in a total of 54 motion combinations. In the actual respiratory waveform mode, respiratory waveforms of 5 randomly selected patients from Affiliated Cancer Hospital of Zhengzhou University were obtained. Under each motion combination, TrueFISP cine images (30 frames, with an acquisition time of 11 s per frame) were obtained. The code was used to automatically identify the two-dimensional coordinates of the center of the simulated tumor in each image, and sin and cos4 functions were separately employed to fit the tumor position in the motion direction, thereby obtaining the fitted motion period and amplitude. The difference between the maximum and minimum values of the tumor's center coordinates in the head-to-foot direction is taken as the range of movement, referred to as the calculated amplitude. For the actual respiratory waveform, the distance between the measured maximum and minimum positions is used to calculate the amplitude.Results:In the head-foot motion mode, the fitted amplitudes of both sin and cos4 waveforms deviated from the set amplitudes by 0-0.51 mm, with relative deviations of 0%-4.2%. The deviation range between the calculated amplitudes and the set amplitudes of the two waveforms were 0.08-0.94 mm, with relative deviations of 1.1%-6.3%. In the rotation motion mode, the fitted amplitudes deviated from the set amplitudes by 0-0.61 mm, with relative deviations of 0%-6.2%. And the deviation range between the calculated amplitudes and the set amplitudes were 0.16-0.94 mm, with relative deviations of 0%-6.3%. In the actual respiratory waveform motion mode, the deviation range between the calculated amplitudes and the set amplitudes were 0.10-0.48 mm, with relative deviations of 2.2%-8.6%.Conclusion:TrueFISP cine sequences show minimal deviations in determining the range of tumor head-foot motion and effectively captures the tumor's movement state, thereby providing important support for the precise definition of the tumor movement target area during radiotherapy .

Male patients with prolactinomas usually present with typical hyperprolactinemia symptoms, including sexual dysfunction and infertility. However, clinical factors related to sexual dysfunction and surgical outcomes in these patients remain unclear. This study aimed to investigate the outcomes of male patients with prolactinomas after transsphenoidal surgery and the risk factors affecting sexual dysfunction. This study was conducted on 58 male patients who underwent transsphenoidal surgery for prolactinomas between May 2014 and December 2020 at the First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China. We evaluated the sexual function of patients before and after surgery through International Index of Erectile Function-5 scores, libido, and frequency of morning erection. Of the 58 patients, 48 (82.8%) patients had sexual intercourse preoperatively. Among those 48 patients, 41 (85.4%) patients presented with erectile dysfunction. The preoperative International Index of Erectile Function-5 scores in patients with macroprolactinomas were significantly higher than those in patients with giant prolactinomas (17.63 ± 0.91 vs 13.28 ± 1.43; P = 0.01). Postoperatively, the incidence of erectile dysfunction was 47.9%, which was significantly lower than that preoperatively (85.4%; P = 0.01). Twenty-eight (68.3%) patients demonstrated an improvement in erectile dysfunction. Tumor size and invasiveness were significantly correlated with the improvement of erectile dysfunction. Preoperative testosterone <2.3 ng ml^-1 was an independent predictor of improvement in erectile dysfunction. In conclusion, our results indicated that tumor size and invasiveness were important factors affecting the improvement of sexual dysfunction in male patients with prolactinoma. The preoperative testosterone level was an independent predictor related to the improvement of erectile dysfunction.
Humans ; Male ; Prolactinoma/surgery* ; Erectile Dysfunction/etiology* ; Retrospective Studies ; Sexual Dysfunction, Physiological/complications* ; Testosterone ; Pituitary Neoplasms/pathology*

Objective: To analyze the factors associated with readmission within three months of surgery for gastric cancer and the impact of readmission on patients' long-term nutritional status and quality of life. Methods: This was a prospective cohort study comprising patients who underwent radical gastrectomy in the Department of Pancreatic and Gastric Surgery, National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences from October 2018 to August 2019. Patients who failed to complete postoperative follow-up, whose body mass index (BMI) could not be accurately estimated, or who were unable to complete a quality-of-life questionnaire were excluded. The patients were followed up for 12 months. Time to, cause(s) of, and outcomes of readmission were followed up 1, 2 and 3 months postoperatively. BMI was followed up 1, 3, 6 and 12 months postoperatively. Results of blood tests were collected and patients' nutritional status and quality of life were assessed 12 months postoperatively. Nutritional status was evaluated by BMI, hemoglobin, albumin, and total lymphocyte count. Quality of life was evaluated using the European Organization for Research in the Treatment of Cancer (EORTC) Quality of Life scale. The higher the scores for global health and functional domains, the better the quality of life, whereas the higher the score in the symptom domain, the worse the quality of life. Results: The study cohort comprised 259 patients with gastric cancer, all of whom were followed up for 3 months and 236 of whom were followed up for 12 months. Forty-four (17.0%) patients were readmitted within 3 months. The commonest reasons for readmission were gastrointestinal dysfunction (16 cases, 36.3%), intestinal obstruction (8 cases, 18.2%), and anastomotic stenosis (8 cases, 18.2%). Logistic regression analysis showed that preoperative Patient-Generated Subjective Global Assessment score ≥ 4 points (OR=1.481, 95% CI: 1.028‒2.132), postoperative complications (OR=3.298, 95%CI:1.416‒7.684) and resection range (OR=1.582, 95% CI:1.057‒2.369) were risk factors for readmission within 3 months of surgery. Compared with patients who had not been readmitted 12 months after surgery, patients who were readmitted within 3 months of surgery tended to have greater decreases in their BMI [-2.36 (-5.13,-0.42) kg/m² vs. -1.73 (-3.33,-0.33) kg/m², Z=1.850, P=0.065), significantly lower hemoglobin and albumin concentrations [(122.1±16.6) g/L vs. (129.8±18.4) g/L, t=2.400, P=0.017]; [(40.9±5.0) g/L vs. (43.4±3.3) g/L, t=3.950, P<0.001], and significantly decreased global health scores in the quality of life assessment [83 (67, 100) vs. 100 (83, 100), Z=2.890,P=0.004]. Conclusion: Preoperative nutritional risk, total or proximal radical gastrectomy, and complications during hospitalization are risk factors for readmission within 3 months of surgery for gastric cancer. Perioperative management and postoperative follow-up should be more rigorous. Readmission within 3 months after surgery may be associated with a decline in long-term nutritional status and quality of life. Achieving improvement in long-term nutritional status and quality of life requires tracking of nutritional status, timely evaluation, and appropriate interventions in patients who need readmission.
Humans ; Nutritional Status ; Quality of Life ; Patient Readmission ; Stomach Neoplasms/complications* ; Prospective Studies ; Postoperative Complications/etiology* ; Gastrectomy/adverse effects* ; Retrospective Studies