Highly accurate and effective deep neural networks in pathological diagnosis of prostate cancer.

PURPOSE: To established an AI system to make the pathological diagnosis of prostate cancer. METHODS: Prostate histopathological whole mount (WM) sections from patients underwent robot-assisted laparoscopic prostatectomy were prepared. All the prostate WM pathological sections were converted to digital image data and marked with different colors on the basis of the ISUP Gleason grade group. The image was then fed into a segmentation algorithm. We chose modified U-Net as our fundamental network architecture. RESULTS: 172 patients were involved in this study. 896 pieces of prostate WM pathological sections from 160 patients, in which 826 pieces of WM sections from 148 patients were assigned to the training set randomly. After image segmentation there were totally 2,138,895 patches, of which 1,646,535 patches were valid for training. The other WM section was arranged for testing. Based on the whole image testing, AI and pathologists presented the same answers among 21 of 22 pieces of sections. To evaluate the diagnostic results at the pixel level, we anticipated correct cancer or non-cancer diagnose from this AI system. The area under the ROC curve as 96.8%. The value of pixel accuracy of three methods (binary analysis, clinically oriented analysis and analysis for different ISUP Gleason grade) were 96.93%, 95.43% and 93.88%, respectively. The value of frequency weighted IoU were 94.32%, 92.13% and 90.21%, respectively. CONCLUSIONS: This AI system is able to assist pathologists to make a final diagnosis, indicating the great potential and a wide-range of applications of AI in the medical field.

Potassium sodium hydrogen citrate intervention on gut microbiota and clinical features in uric acid stone patients.

The high recurrence rate of renal uric acid stone (UAS) poses a significant challenge for urologists, and potassium sodium hydrogen citrate (PSHC) has been proven to be an effective oral dissolution drug. However, no studies have investigated the impact of PSHC on gut microbiota and its metabolites during stone dissolution therapy. We prospectively recruited 37 UAS patients and 40 healthy subjects, of which 12 patients completed a 3-month pharmacological intervention. Fasting vein blood was extracted and mid-stream urine was retained for biochemical testing. Fecal samples were collected for 16S ribosomal RNA (rRNA) gene sequencing and short chain fatty acids (SCFAs) content determination. UAS patients exhibited comorbidities such as obesity, hypertension, gout, and dyslipidemia. The richness and diversity of the gut microbiota were significantly decreased in UAS patients, Bacteroides and Fusobacterium were dominant genera while Subdoligranulum and Bifidobacterium were poorly enriched. After PSHC intervention, there was a significant reduction in stone size accompanied by decreased serum uric acid and increased urinary pH levels. The abundance of pathogenic bacterium Fusobacterium was significantly downregulated following the intervention, whereas there was an upregulation observed in SCFA-producing bacteria Lachnoclostridium and Parasutterella, leading to a significant elevation in butyric acid content. Functions related to fatty acid synthesis and amino acid metabolism within the microbiota showed upregulation following PSHC intervention. The correlation analysis revealed a positive association between stone pathogenic bacteria abundance and clinical factors for stone formation, while a negative correlation with SCFAs contents. Our preliminary study revealed that alterations in gut microbiota and metabolites were the crucial physiological adaptation to PSHC intervention. Targeted regulation of microbiota and SCFA holds promise for enhancing drug therapy efficacy and preventing stone recurrence. KEY POINTS: • Bacteroides and Fusobacterium were identified as dominant genera for UAS patients • After PSHC intervention, Fusobacterium decreased and butyric acid content increased • The microbiota increased capacity for fatty acid synthesis after PSHC intervention.

Prediction of false-positive PI-RADS 5 lesions on prostate multiparametric MRI: development and internal validation of a clinical-radiological characteristics based nomogram.

BACKGROUND: To develop a risk model including clinical and radiological characteristics to predict false-positive The Prostate Imaging Reporting and Data System (PI-RADS) 5 lesions. METHODS: Data of 612 biopsy-naïve patients who had undergone multiparametric magnetic resonance imaging (mpMRI) before prostate biopsy were collected. Clinical variables and radiological variables on mpMRI were adopted. Lesions were divided into the training and validation cohort randomly. Stepwise multivariate logistic regression analysis with backward elimination was performed to screen out variables with significant difference. A diagnostic nomogram was developed in the training cohort and further validated in the validation cohort. Calibration curve and receiver operating characteristic (ROC) analysis were also performed. RESULTS: 296 PI-RADS 5 lesions in 294 patients were randomly divided into the training and validation cohort (208 : 88). 132 and 56 lesions were confirmed to be clinically significant prostate cancer in the training and validation cohort respectively. The diagnostic nomogram was developed based on prostate specific antigen density, the maximum diameter of lesion, zonality of lesion, apparent diffusion coefficient minimum value and apparent diffusion coefficient minimum value ratio. The C-index of the model was 0.821 in the training cohort and 0.871 in the validation cohort. The calibration curve showed good agreement between the estimation and observation in the two cohorts. When the optimal cutoff values of ROC were 0.288 in the validation cohort, the sensitivity, specificity, PPV, and NPV were 90.6%, 67.9%, 61.7%, and 92.7% in the validation cohort, potentially avoiding 9.7% unnecessary prostate biopsies. CONCLUSIONS: We developed and validated a diagnostic nomogram by including 5 factors. False positive PI-RADS 5 lesions could be distinguished from clinically significant ones, thus avoiding unnecessary prostate biopsy.

Incidence, risk factors, and significance of 20% decrease from new baseline estimated glomerular filtration rate after radical and partial nephrectomy within 2 years.

OBJECTIVES: To evaluate the incidence and risk factors of a 20% decrease from new baseline (NB)-estimated glomerular filtration rate (eGFR) within 2 years after radical nephrectomy (RN) and partial nephrectomy (PN) and to examine the difference in the incidence of end-stage renal disease (ESRD) with or without the 20% decrease. METHODS: This retrospective study included 238 patients undergoing RN and 369 undergoing PN for cT1a-cT3a renal cancer. The incidence of a 20% decrease from NB-eGFR within 2 years after RN/PN was examined and its potential risk factors including surgery type were assessed by multivariate logistic regression analysis. The development of ESRD was analyzed as an endpoint and its incidence was compared according to the presence or absence of the 20% decrease from NB-eGFR within 2 years. RESULTS: Overall, the 20% decrease from NB-eGFR within 2 years was observed in 37 patients (6.1%), including 10 (4.2%) and 27 (7.3%) after RN and PN, respectively (p = 0.117). Diabetes mellitus, proteinuria, and perioperative complications were shown to be independent risk factors for the 20% decrease from NB-eGFR, while surgery type was not. During the median follow-up of 65 months, the ESRD-free survival rate at 6 years was 75.5% and 99.6% in patients with and without the 20% decrease from NB-eGFR, respectively (p < 0.001), while no significant difference was observed between patients undergoing RN and PN (98.1% and 98.7%, p = 0.561). CONCLUSIONS: Because the incidence of ESRD after the 20% decrease from NB-eGFR within 2 years was as high as 24.5% at 6 years, these patients should be followed with utmost care.

Autonomous Landing of Quadrotor Unmanned Aerial Vehicles Based on Multi-Level Marker and Linear Active Disturbance Reject Control.

Landing on unmanned surface vehicles (USV) autonomously is a critical task for unmanned aerial vehicles (UAV) due to complex environments. To solve this problem, an autonomous landing method is proposed based on a multi-level marker and linear active disturbance rejection control (LADRC) in this study. A specially designed landing board is placed on the USV, and ArUco codes with different scales are employed. Then, the landing marker is captured and processed by a camera mounted below the UAV body. Using the efficient perspective-n-point method, the position and attitude of the UAV are estimated and further fused by the Kalman filter, which improves the estimation accuracy and stability. On this basis, LADRC is used for UAV landing control, in which an extended state observer with adjustable bandwidth is employed to evaluate disturbance and proportional-derivative control is adopted to eliminate control error. The results of simulations and experiments demonstrate the feasibility and effectiveness of the proposed method, which provides an effective solution for the autonomous recovery of unmanned systems.

Cardiovascular outcomes among patients with castration-resistant prostate cancer: A comparative safety study using US administrative claims data.

BACKGROUND: Cardiovascular conditions are the most prevalent comorbidity among patients with prostate cancer, regardless of treatment. Additionally, cardiovascular risk has been shown to increase following exposure to certain treatments for advanced prostate cancer. There is conflicting evidence on risk of overall and specific cardiovascular outcomes among men treated for metastatic castrate resistant prostate cancer (CRPC). We, therefore, sought to compare incidence of serious cardiovascular events among CRPC patients treated with abiraterone acetate plus predniso(lo)ne (AAP) and enzalutamide (ENZ), the two most widely used CRPC therapies. METHODS: Using US administrative claims data, we selected CRPC patients newly exposed to either treatment after August 31, 2012, with prior androgen deprivation therapy (ADT). We assessed incidence of hospitalization for heart failure (HHF), ischemic stroke, and acute myocardial infarction (AMI) during the period 30-days after AAP or ENZ initiation to discontinuation, outcome occurrence, death, or disenrollment. We matched treatment groups on propensity-scores (PSs) to control for observed confounding to estimate the average treatment effect among the treated (AAP) using conditional Cox proportional hazards models. To account for residual bias, we calibrated our estimates against a distribution of effect estimates from 124 negative-control outcomes. RESULTS: The HHF analysis included 2322 (45.1%) AAP initiators and 2827 (54.9%) ENZ initiators. In this analysis, the median follow-up times among AAP and ENZ initiators (after PS matching) were 144 and 122 days, respectively. The empirically calibrated hazard ratio (HR) estimate for HHF was 2.56 (95% confidence interval [CI]: 1.32, 4.94). Corresponding HRs for AMI and ischemic stroke were 1.94 (95% CI: 0.90, 4.18) and 1.25 (95% CI: 0.54, 2.85), respectively. CONCLUSIONS: Our study sought to quantify risk of HHF, AMI and ischemic stroke among CRPC patients initiating AAP relative to ENZ within a national administrative claims database. Increased risk for HHF among AAP compared to ENZ users was observed. The difference in myocardial infarction did not attain statistical significance after controlling for residual bias, and no differences were noted in ischemic stroke between the two treatments. These findings confirm labeled warnings and precautions for AAP for HHF and contribute to the comparative real-world evidence on AAP relative to ENZ.

CT-quantified sarcopenic visceral obesity is associated with poor transplant waitlist mortality in patients with cirrhosis.

Sarcopenic obesity is associated with higher rates of morbidity and mortality than seen with either sarcopenia or obesity alone. We aimed to define sarcopenic visceral obesity (SVO) using CT-quantified skeletal muscle index and visceral-to-subcutaneous adipose tissue ratio and to examine its association with waitlist mortality in patients with cirrhosis. Included were 326 adults with cirrhosis awaiting liver transplantation in the ambulatory setting with available abdominal CT within 6 months from enrollment between February 2015 and January 2018. SVO was defined as patients with sarcopenia (skeletal muscle index <50 cm 2 /m 2 in men and <39 cm 2 /m 2 in women) and visceral obesity (visceral-to-subcutaneous adipose tissue ratio ≥1.21 in men and ≥0.48 in women). The percentage who met criteria for sarcopenia, visceral obesity, and SVO were 44%, 29%, and 13%, respectively. Cumulative incidence of waitlist mortality was higher in patients with SVO compared to patients with sarcopenia without visceral obesity or visceral obesity without sarcopenia at 12 months (40% vs. 21% vs. 12%) (overall logrank p =0.003). In univariable Cox regression, SVO was associated with waitlist mortality (HR: 3.42, 95% CI: 1.58-7.39), which remained significant after adjusting for age, sex, diabetes, ascites, encephalopathy, MELDNa, liver frailty index, and different body compositions (HR: 2.64, 95% CI: 1.11-6.30). SVO was associated with increase waitlist mortality in patients with cirrhosis in the ambulatory setting awaiting liver transplantation. Concurrent loss of skeletal muscle and gain of adipose tissue seen in SVO quantified by CT may be a useful and objective measurement to identify patients at risk for suboptimal pretransplant outcomes.

Flexible strain sensor based on a frequency selective surface.

Frequency selective surfaces (FSSs), modern artificial materials, show great potential in engineering applications due to their excellent frequency selection capabilities. In this paper, we introduce a flexible strain sensor based on FSS reflection characteristics, which can be well conformally attached to the surface of an object and bear mechanical deformation from a certain load. When the FSS structure changes, the original working frequency will be shifted. By measuring the difference in electromagnetic performance, the strain degree of the object can be monitored in real-time. In this study, we designed an FSS sensor with a working frequency of 31.4 GHz and amplitude that reaches -35 dB that exhibits favorable resonance properties in the Ka-band. The quality factor of FSS is 16.2, which indicates that the sensor has excellent sensing performance. The sensor was applied in the strain detection of a rocket engine case through statics and electromagnetic simulations. The analysis showed that the working frequency of the sensor shifted by approximately 200 MHz for 1.64% radial expansion of the engine case and the frequency shift exhibits an excellent linear relationship with the deformation in diverse loads, so it can be used for accurate strain detection of the case. Based on experiments, we carried out the uniaxial tensile test of the FSS sensor in this study. The sensor's sensitivity was 1.28 GHz/mm when the FSS was stretched by 0-3 mm in the test. Therefore, the FSS sensor has high sensitivity and strong mechanical properties, which verifies the practical value of the FSS structure designed in this paper. It has a broad development space in this field.

Very high-frequency, gate-tunable CrPS4 nanomechanical resonator with single mode.

Two-dimensional (2D) antiferromagnetic semiconductor chromium thiophosphate (CrPS4) has gradually become a major candidate material for low-dimensional nanoelectromechanical devices due to its remarkable structural, photoelectric characteristics and potentially magnetic properties. Here, we report the experimental study of a new few-layer CrPS4 nanomechanical resonator demonstrating excellent vibration characteristics through the laser interferometry system, including the uniqueness of resonant mode, the ability to work at the very high frequency, and gate tuning. In addition, we demonstrate that the magnetic phase transition of CrPS4 strips can be effectively detected by temperature-regulated resonant frequencies, which proves the coupling between magnetic phase and mechanical vibration. We believe that our findings will promote the further research and applications of the resonator for 2D magnetic materials in the field of optical/mechanical signal sensing and precision measurement.

Gate-tunable bolometer based on strongly coupled graphene mechanical resonators.

Bolometers based on graphene have demonstrated outstanding performance with high sensitivity and short response time. In situ adjustment of bolometers is very important in various applications, but it is still difficult to implement in many systems. Here we propose a gate-tunable bolometer based on two strongly coupled graphene nanomechanical resonators. Both resonators are exposed to the same light field, and we can measure the properties of one bolometer by directly tracking the resonance frequency shifts, and indirectly measure the other bolometer through mechanical coupling. We find that the sensitivity and the response bandwidth of both bolometers can be independently adjusted by tuning the corresponding gate voltages. Moreover, the properties of the indirectly measured bolometer show a dependence on the coupling between the two resonators, with other parameters being fixed. Our method has the potential to optimize the design of large-scale bolometer arrays, and open new horizons in infrared/terahertz astronomy and communication systems.

Tuning Superinductors by Quantum Coherence Effects for Enhancing Quantum Computing.

Research on spatially inhomogeneous weakly coupled superconductors has recently received a boost of interest because of the experimental observation of a dramatic enhancement of the kinetic inductance with relatively low losses. Here, we study the kinetic inductance and the quality factor of a strongly disordered, weakly coupled superconducting thin film. We employ a gauge-invariant random-phase approximation capable of describing collective excitations and other fluctuations. In line with the experimental findings, we have found that in the range of frequencies of interest, and for sufficiently low temperatures, an exponential increase of the kinetic inductance with disorder coexists with a still large quality factor of ∼10^{4}. More interestingly, on the metallic side of the superconductor-insulator transition, we have identified a range of frequencies and temperatures, T∼0.1T_{c}, where quantum coherence effects induce a broad statistical distribution of the quality factor with an average value that increases with disorder. We expect these findings to further stimulate experimental research on the design and optimization of superinductors for a better performance and miniaturization of quantum devices such as qubit circuits and microwave detectors.

Comparative Analysis of Super-Mini Percutaneous Nephrolithotomy Combined with Flexible Ureteroscopic Lithotripsy versus Flexible Ureteroscopic Lithotripsy Alone for Treating Complex Kidney Stones: A Retrospective Study of 205 Patients.

BACKGROUND This retrospective study aimed to compare outcomes from super-mini percutaneous nephrolithotomy (SMP) combined with flexible ureteroscopic lithotripsy (FURL) and FURL alone in 205 patients with 2.5-4.2 cm diameter complex kidney stones. MATERIAL AND METHODS Between January 2018 and December 2022, 92 patients were treated with SMP combined with FURL (group A), and 113 patients were treated with FURL alone (group B). The stone-free rate (SFR), retreatment ratio, operation time, mean decline in hemoglobin level, postoperative pain visual analogue scale (VAS), and postoperative hospitalization time and complications were analyzed and compared between the 2 groups. RESULTS The SFR 3 days after the operation was 85.87% in group A, which was significantly higher than that in group B (72.57%) (P=0.021). The rate of retreatment in group A (3.26%) was significantly lower than that in group B (10.62%) (P=0.044). The SFR after 90 days was higher in group A (94.57%) than in group B (90.27%) (P=0.254). The mean decrease in hemoglobin, postoperative hospitalization duration, and VAS score 6 hours after the operation were all significantly higher in group A than in group B (P<0.05). However, there was no significant difference in operation time, VAS score at 12 and 24 hours after the operation, and complication rate. CONCLUSIONS In the treatment of complex renal stones, compared with FURL, SMP combined with FURL in the oblique supine lithotomy position has the advantages of a higher early SFR with no increased risk of complications.

Trends of radical cystectomy and comparisons of surgical outcomes among surgical approaches focusing on robot-assisted radical cystectomy: A Japanese nationwide database study.

OBJECTIVE: To clarify the trends in radical cystectomy and to compare surgical outcomes among surgical approaches focusing on robot-assisted radical cystectomy based on a Japanese nationwide database. METHODS: The Diagnosis Procedure Combination database was used to extract data on radical cystectomy cases. Trends in open radical cystectomy, laparoscopic radical cystectomy, minimum incision endoscopic radical cystectomy, and robot-assisted radical cystectomy between April 2012 and March 2021 were evaluated. Basic characteristics and peri-operative indicators were compared among the four groups. Propensity score matching was applied to assess the differences between open radical cystectomy and robot-assisted radical cystectomy. RESULTS: During the study period, a decreasing number of open radical cystectomies and an increasing number of minimally invasive radical cystectomies were shown in the total cohort of 28 345 cases. The number of robot-assisted radical cystectomies rapidly increased after government approval in 2018. Minimally invasive radical cystectomies, including robot-assisted radical cystectomies, had a significantly lower complication rate, a shorter length of stay, and a lower blood transfusion rate, but a longer anesthesia time than open radical cystectomies. In the propensity score matching analysis comparing the surgical outcomes of robot-assisted radical cystectomy and open radical cystectomy, similar results were demonstrated, and blood transfusion rates were equivalent. CONCLUSION: For the past decade, the number of minimally invasive radical cystectomies has steadily increased without compromised surgical outcomes, except for anesthesia time. Robot-assisted radical cystectomies in particular rapidly became widespread in Japan after government approval in 2018 and became a standard surgery within the first 3 years.

Surgical outcomes of robot-assisted radical cystectomy in octogenarian or older patients: A Japanese nationwide study.

OBJECTIVE: To evaluate the surgical outcomes of robot-assisted radical cystectomy (RARC) in octogenarian or older patients based on a Japanese nationwide database. METHODS: The diagnosis procedure combination database was used to extract the data on radical cystectomy cases. Surgical outcomes of RARC in octogenarian or older patients (older group) were initially compared to those of patients younger than 80 years (younger group). Then, the surgical outcomes of RARC in the older group were compared to those of open radical cystectomy (ORC) and laparoscopic radical cystectomy (LRC) in the same age group. RESULTS: Between 2018 and 2021, 478 RARC cases in the older group and 2257 RARC cases in the younger group were identified. In the older group, ileal conduit, neobladder, and other urinary diversions were carried out in 352 (73.6%), 22 (4.6%), and 104 (21.8%) patients, respectively. In the older group, when compared with the younger group, the complication rate (24.9%), blood transfusion rate (41.4%), and in-hospital mortality (1.4%) were equivalent, while significantly shorter anesthesia time and longer length of stay were observed in the older group (521.0 ± 140.4 min vs. 595.1 ± 141.71 min, p < 0.01, and 32.9 ± 16.8 days vs. 30.6 ± 17.8 days, p = 0.01, respectively). In the comparison of the surgical outcomes of older patients receiving RARC to those receiving ORC (n = 746) and LRC (n = 375), the RARC group had the lowest complication rate and the shortest length of stay, while the shortest anesthesia time was noted in the ORC group. CONCLUSION: The feasibility of RARC for octogenarian or older patients was demonstrated by the nationwide database study.

Significance of dorsal bladder neck involvement in predicting the progression of non-muscle-invasive bladder cancer.

OBJECTIVES: Accurately predicting of progression is important for patients with non-muscle-invasive bladder cancer (NMIBC). We previously reported that bladder neck involvement (BNI) was significantly associated with progression of NMIBC. In this study, we evaluated the prognostic significance of the detailed BNI location in NMIBC patients. METHODS: We retrospectively reviewed 651 patients diagnosed with primary NMIBC at a single center between 2000 and 2018. Using the detailed BNI location, patients were divided into the following three groups: dorsal BNI (BNId; 4 to 8 o'clock position), ventral BNI (BNIv; 8 to 4 o'clock but not 4 to 8 o'clock position), and non-BNI group. Both time to progression to muscle-invasive disease and distant metastasis was compared among the three groups. A prognostic model was developed and its discriminative ability was evaluated. RESULTS: Dorsal bladder neck involvement and BNIv were observed in 43 (6.6%) and 36 (5.5%) patients, respectively. During a median follow-up of 61 months, 35 (5.4%) patients progressed. The cumulative incidence at 5 years was 12%, 0%, and 5.0% in BNId, BNIv, and non-BNI groups, respectively. On multivariate analysis, BNId was a significant and independent risk factor for progression, tumor stage pT1, and histologic grade G3. One point was assigned to each factor, and patients were classified into four well-stratified prognostic groups based on the total score. CONCLUSION: Dorsal bladder neck involvement was an independent and significant risk factor for progression in primary NMIBC. Our simple and practical prognostic model including BNId is easy to use and may help selecting the optimal treatment and its timing.

What contributes to local-level institutional adaptation under climate change? A configurational approach based on evidence from China's Sponge City Program.

Unrestrained human industrial and agricultural production activities exacerbate climate change and environmental pollution. Climate change leads to an increase in flood risks and the spread of water and soil pollution, resulting in challenges in urban stormwater management. Institutional adaptation to climate change is vital for realizing effective local urban stormwater management. However, the accumulated knowledge on climate adaptation over the past decade has been concentrated at the technical and economic levels, with limited research on institutional adaptation. The Sponge City Program in China selects 30 pilot cities to promote a novel stormwater management approach that combines the reliability of traditional gray infrastructures made of concrete materials with the adaptability and sustainability of green-blue infrastructures based on natural-based solutions, but the extent of institutional adaptation in this process varies considerably across pilot cities. To explain what drives institutional adaptation, a configurational analysis of pilot cities is conducted using the fuzzy-set qualitative comparative analysis method. Based on data from 628 official reports and 36 interviews, we demonstrate local governments are significant institutional entrepreneurs, and high institutional adaptation occurs with the combined effects of institutional capacity, financial resources, and reputational incentives. There are three types of paths driving institutional adaptation: "strong institutional capacity-strong financial resource-low reputational reserve," "strong institutional capacity-strong financial resource-high reputational competition," and "strong institutional capacity-weak financial resource-low reputational reserve." These three paths account for 72% of the instances of high institutional adaptation outcomes, and 90% of cases share a given configuration of conditions associated with an outcome. Our conclusion advances a theoretical understanding of the drivers of institutional adaptation and provides guidelines for future climate adaptation practices.

Biotransformation of Ursonic Acid by Aspergillus ochraceus and Aspergillus oryzae to Discover Anti-Neuroinflammatory Derivatives.

Biotransformation of ursonic acid (1) by two fungal strains Aspergillus ochraceus CGMCC 3.5324 and Aspergillus oryzae CGMCC 3.407 yielded thirteen new compounds (4, 5, 7-10, and 13-19), along with five recognized ones. The structural details of new compounds were determined through spectroscopic examination (NMR, IR, and HR-MS) and X-ray crystallography. Various modifications, including hydroxylation, epoxidation, lactonization, oxygen introduction, and transmethylation, were identified on the ursane core. Additionally, the anti-neuroinflammatory efficacy of these derivatives was assessed on BV-2 cells affected by lipopolysaccharides. It was observed that certain methoxylated and epoxylated derivatives (10, 16, and 19) showcased enhanced suppressive capabilities, boasting IC50 values of 8.2, 6.9, and 5.3 µM. Such ursonic acid derivatives might emerge as potential primary molecules in addressing neurodegenerative diseases.

Chemistry and biological activity of resin glycosides from Convolvulaceae species.

Carbohydrate-based drug discovery has gained more and more attention during the last few decades. Resin glycoside is a kind of novel and complex glycolipids mainly distributed in plants of the family Convolvulaceae. Over the last decade, a number of natural resin glycosides and derivatives have been isolated and identified, and exhibited a broad spectrum of biological activities, such as cytotoxic, multidrug-resistant reversal on both microbial pathogens and mammalian cancer cells, antivirus, anticonvulsant, antidepressant, sedative, vasorelaxant, laxative, and α-glucosidase inhibitory effects, indicating their potential as lead compounds for drug discovery. A systematic review of the literature studies was carried out to summarize the chemistry and biological activity of resin glycosides from Convolvulaceae species, based on various data sources such as PubMed, Web of Science, Scopus, and Google scholar. The keyword "Convolvulaceae" was paired with "resin glycoside," "glycosidic acid," "glycolipid," or "oligosaccharide," and the references published between 2009 and June 2021 were covered. In this article, we comprehensively reviewed the structures of 288 natural resin glycoside and derivatives newly reported in the last decade. Moreover, we summarized the biological activities and mechanisms of action of the resin glycosides with pharmaceutical potential. Taken together, great progress has been made on the chemistry and biological activity of resin glycosides from Convolvulaceae species, however, more exploratory research is still needed, especially on the mechanism of action of the biological activities.

Hydroamination of Unactivated Alkenes with Aliphatic Azides.

We report here an efficient and highly diastereoselective intermolecular anti-Markovnikov hydroamination of unactivated alkenes with aliphatic azides in the presence of silane. The system tolerates a wide range of azides and alkenes and operates with alkene as limiting reagent. Mechanistic studies suggest a radical chain pathway that involves aminium radical formation, radical addition to alkenes and HAT from silane to ß-aminium alkyl radical. The use of sterically bulky silane is proposed to contribute to the excellent diastereoselectivity for HAT. Computational analysis uncovers the reaction pathway of aliphatic azide activation with silyl radical for aminyl radical formation.

The analgesic effects of ß-elemene in rats with neuropathic pain by inhibition of spinal astrocytic ERK activation.

Neuropathic pain takes a heavy toll on individual well-being, while current therapy is far from desirable. Herein, we assessed the analgesic effect of ß-elemene, a chief component in the traditional Chinese medicine Curcuma wenyujin, and explored the underlying mechanisms at the level of spinal dorsal horn (SDH) under neuropathic pain. A spared nerve injury (SNI)-induced neuropathic pain model was established in rats. Intraperitoneal injection (i.p.) of ß-elemene was administered for 21 consecutive days. Mechanical allodynia was explored by von Frey filaments. The activation of the mitogen-activated protein kinase (MAPK) family (including ERK, p38, and JNK) in spinal neurons, astrocytes, and microglia was evaluated using immunostaining 29 days after SNI surgery. The expression of GFAP, Iba-1, p-ERK, p-JNK, and p-p38 within the SDH was measured using immunoblotting. The levels of proinflammatory cytokines (including TNF-α, IL-1ß, and IL-6) were measured with ELISA. The levels of oxidative stress indicators (including MDA, SOD, and GSH-PX) were detected using biochemical tests. Consecutive i.p. administration of ß-elemene relieved SNI-induced mechanical allodynia (with an EC50 of 16.40 mg/kg). SNI significantly increased the expression of p-ERK in spinal astrocytes but not microglia on day 29. ß-elemene reversed spinal astrocytic ERK activation and subsequent upregulation of proinflammatory cytokines in SNI rats, with no effect on the expression of p38 and JNK in spinal glia. ß-elemene also exerted antioxidative effects by increasing the levels of SOD and GSH-PX and decreasing the level of MDA. Our results suggest that SNI induces robust astrocytic ERK activation within the SDH in the late phase of neuropathic pain. ß-elemene exerts remarkable analgesic effects on neuropathic pain, possibly by inhibiting spinal astrocytic ERK activation and subsequent neuroinflammatory processes. Our findings suggest that ß-elemene might be a promising analgesic for the treatment of chronic pain.