Perioperative acute kidney injury: The renoprotective effect and mechanism of dexmedetomidine.

Dexmedetomidine (DEX) is a highly selective and potent α2-adrenoceptor (α2-AR) agonist that is widely used as a clinical anesthetic to induce anxiolytic, sedative, and analgesic effects. In recent years, a growing body of evidence has demonstrated that DEX protects against acute kidney injury (AKI) caused by sepsis, drugs, surgery, and ischemia-reperfusion (I/R) in organs or tissues, indicating its potential role in the prevention and treatment of AKI. In this review, we summarized the evidence of the renoprotective effects of DEX on different models of AKI and explored the mechanism. We found that the renoprotective effects of DEX mainly involved antisympathetic effects, reducing inflammatory reactions and oxidative stress, reducing apoptosis, increasing autophagy, reducing ferroptosis, protecting renal tubular epithelial cells (RTECs), and inhibiting renal fibrosis. Thus, the use of DEX is a promising strategy for the management and treatment of perioperative AKI. The aim of this review is to further clarify the renoprotective mechanism of DEX to provide a theoretical basis for its use in basic research in various AKI models, clinical management, and the treatment of perioperative AKI.

Riboflavin protects against pancreatic cancer metastasis by targeting TGF-ß receptor 1.

The inhibition of transforming growth factor-ß1 (TGF-ß1) signaling by targeting TGF-ß receptor 1 (TßR1) has been considered as an ideal approach for the prevention of pancreatic cancer metastasis. Utilizing a pharmacophore model for TßR1 inhibitors, candidate compounds with the potential TßR1 binding ability were screened from the U.S. Food and Drug Administration (FDA) database, and riboflavin (RF) with a highest fit value was chosen to investigate its binding ability to TßR1 and effect on TGF-ß1 signaling in pancreatic cancer cells. Molecular docking and cellular thermal shift assay (CETSA) proved that RF at pharmacological concentrations could directly bind to TßR1. Further studies showed that pharmacological concentrations of RF in vitro could block TGF-ß1 signaling, suppress the migration and invasion, and prevent epithelial-mesenchymal transition (EMT) process of pancreatic cancer cells in the absence or presence of TGF-ß1 stimulation, indicating that RF presented anti-metastatic effect in pancreatic cancer cells. Knockdown of TßR1 could significantly attenuate the effects of RF on the migration and EMT process in pancreatic cancer cells, further confirming that the anti-metastatic effect of RF was achieved by blocking TGF-ß1 signaling after binding to TßR1. Moreover, in a mouse model of pancreatic cancer metastasis, it was certified that RF administration could block lung and liver metastases, TGF-ß1 signaling and EMT process of pancreatic cancer in vivo. In summary, our findings showed that RF could block TGF-ß1 signaling by directly binding to TßR1, thereby suppressing the metastasis of pancreatic cancer cells by inhibiting EMT process both in vitro and in vivo.

Risk factors for infant hearing loss: a meta-analysis.

Hearing loss is a common disability in infants that significantly impacts their cognitive, language, and literacy development. This study aimed to systematically assess the risk factors for the early identification and intervention in infant hearing loss. Databases were searched for meta-analyses of observational studies until November 2023. The quality assessment was performed using the Cochrane risk of bias tool, and the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach was used to assess the certainty of the evidence. A meta-analysis identified 14 risk factors significantly associated with infant hearing loss. According to the GRADE approach, there were four factors with moderate-certainty evidence (low birth weight(LBW), congenital anomalies, craniofacial anomalies, intracranial hemorrhages), seven factors with low-certainty evidence (ototoxic medications, family history of hearing loss, mechanical ventilation > 5 days, intrauterine infection, admission to neonatal intensive care unit (NICU) > 5 days, mechanical ventilation and asphyxia) and six with extremely-low-certainty evidence (very low birth weight < 1500 g (VLBW), hyperbilirubinemia, sepsis or meningitis, male sex, premature birth, small for gestational age (SGA)). Nevertheless, no significant association was found between infant hearing loss and factors such as small for gestational age (SGA), male sex, and premature birth (P > 0.05).  Conclusion: The identification of these 14 interrelated risk factors can prove advantageous in clinical practice, as these findings could guide hearing screening and parental counseling. Furthermore, prospective research could be conducted to develop risk-based scoring systems based on these factors. What is Known: • Infant hearing loss is a worldwide issue. • Risk factors for this condition are debated. What is New: • This is the first meta-analysis to comprehensively evaluate perinatal and postnatal risk factors for hearing loss in infants. • Intracranial hemorrhage, mechanical ventilation, and low birth weight are associated with infant hearing loss. However, no evidence of an association was found between premature birth, being small for gestational age, or male sex and hearing loss.

Risk factors of neonatal stroke from different origins: a systematic review and meta-analysis.

Given the persistent ambiguity regarding the etiology of neonatal stroke across diverse origins, our objective was to conduct a comprehensive evaluation of both qualitative and quantitative risk factors. An exhaustive search of eight databases was executed to amass all pertinent observational studies concerning risk factors for neonatal stroke from various origins. Subsequent to independent screening, data extraction, and bias assessment by two researchers, a meta-analysis was conducted utilizing RevMan and Stata software. Nineteen studies, encompassing a total of 30 factors, were incorporated into this analysis. Beyond established risk factors, our investigation unveiled gestational diabetes (OR, 5.51; P < 0.00001), a history of infertility (OR, 2.44; P < 0.05), placenta previa (OR, 3.92; P = 0.02), postdates (OR, 2.07; P = 0.01), preterm labor (OR, 2.32; P < 0.00001), premature rupture of membranes (OR, 3.02; P = 0.007), a prolonged second stage of labor (OR, 3.94; P < 0.00001), and chorioamnionitis (OR, 4.35; P < 0.00001) as potential risk factors for neonatal cerebral arterial ischemic stroke. Additionally, postdates (OR, 4.31; P = 0.003), preterm labor (OR, 1.60; P < 0.00001), an abnormal CTG tracing (OR, 9.32; P < 0.0001), cesarean section (OR, 4.29; P = 0.0004), male gender (OR, 1.73; P = 0.02), and vaginal delivery (OR, 1.39; P < 0.00001) were associated with an elevated risk for neonatal hemorrhagic stroke. CONCLUSIONS: This study provides a succinct overview and comparative analysis of maternal, perinatal, and additional risk factors associated with neonatal cerebral artery ischemic stroke and neonatal hemorrhagic stroke, furnishing critical insights for healthcare practitioners involved in the diagnosis and prevention of neonatal stroke. This research also broadens the conceptual framework for future investigations. WHAT IS KNOWN: • Research indicates that prenatal, perinatal, and neonatal risk factors can elevate the risk of neonatal arterial ischemic stroke (NAIS). However, the risk factors for neonatal cerebral arterial ischemic stroke remain contentious, and those for neonatal hemorrhagic stroke (NHS) and neonatal cerebral venous sinus thrombosis (CVST) are still not well-defined. WHAT IS NEW: • This study is the inaugural comprehensive review and meta-analysis encompassing 19 studies that explore maternal, perinatal, and various risk factors linked to neonatal stroke of differing etiologies. Notably, our analysis elucidates eight risk factors associated with NAIS: gestational diabetes mellitus, a history of infertility, placenta previa, postdates, preterm birth, premature rupture of membranes, a prolonged second stage of labor, and chorioamnionitis. Furthermore, we identify six risk factors correlated with NHS: postdates, preterm birth, an abnormal CTG, the method of delivery, male gender, and vaginal delivery. Additionally, our systematic review delineates risk factors associated with CVST.

Comparative proteomic analysis of two divergent strains provides insights into thermotolerance mechanisms of Ganoderma lingzhi.

Heat stress (HS) is a major abiotic factor influencing fungal growth and metabolism. However, the genetic basis of thermotolerance in Ganoderma lingzhi (G. lingzhi) remains largely unknown. In this study, we investigated the thermotolerance capacities of 21 G. lingzhi strains and screened the thermo-tolerant (S566) and heat-sensitive (Z381) strains. The mycelia of S566 and Z381 were collected and subjected to a tandem mass tag (TMT)-based proteome assay. We identified 1493 differentially expressed proteins (DEPs), with 376 and 395 DEPs specific to the heat-tolerant and heat-susceptible genotypes, respectively. In the heat-tolerant genotype, upregulated proteins were linked to stimulus regulation and response. Proteins related to oxidative phosphorylation, glycosylphosphatidylinositol-anchor biosynthesis, and cell wall macromolecule metabolism were downregulated in susceptible genotypes. After HS, the mycelial growth of the heat-sensitive Z381 strain was inhibited, and mitochondrial cristae and cell wall integrity of this strain were severely impaired, suggesting that HS may inhibit mycelial growth of Z381 by damaging the cell wall and mitochondrial structure. Furthermore, thermotolerance-related regulatory pathways were explored by analyzing the protein-protein interaction network of DEPs considered to participate in the controlling the thermotolerance capacity. This study provides insights into G. lingzhi thermotolerance mechanisms and a basis for breeding a thermotolerant germplasm bank for G. lingzhi and other fungi.

Lateral scanning Raman scattering lidar for accurate measurement of atmospheric temperature and water vapor from ground to height of interest: publisher's note.

This publisher's note contains corrections to Opt. Lett.48, 2595 (2023).10.1364/OL.488924.

Lateral scanning Raman scattering lidar for accurate measurement of atmospheric temperature and water vapor from ground to height of interest.

A novel lateral scanning Raman scattering lidar (LSRSL) system is proposed, aiming to realize the accurate measurement of atmospheric temperature and water vapor from the ground to a height of interest and to overcome the effect of a geometrical overlap function of backward Raman scattering lidar. A configuration of the bistatic lidar is employed in the design of the LSRSL system, in which four horizontally aligned telescopes mounted on a steerable frame to construct the lateral receiving system are spatially separated to look at a vertical laser beam at a certain distance. Each telescope, combined with a narrowband interference filter, is utilized to detect the lateral scattering signals of the low- and high-quantum-number transitions of the pure rotational Raman scattering spectra and vibrational Raman scattering spectra of N2 and H2O. The profiling of lidar returns in the LSRSL system is performed by the elevation angle scanning of the lateral receiving system, in which the intensities of the lateral Raman scattering signals at each setting of elevation angles are sampled and analyzed. Preliminary experiments are carried out after the construction of a LSRSL system in Xi'an city, whose retrieval results and statistical error analyses present a good performance in the detection of atmospheric temperature and water vapor from the ground to a height of 1.11 km and show the feasibility for combination with backward Raman scattering lidar in atmospheric measurement.

Causal associations between dietary habits and CVD: a Mendelian randomisation study.

Over the years, numerous observational studies have substantiated that various dietary choices have opposing effects on CVD. However, the causal effect has not yet been established. Thus, we conducted a Mendelian randomisation (MR) analysis to reveal the causal impact of dietary habits on CVD. Genetic variants strongly associated with 20 dietary habits were selected from publicly available genome-wide association studies conducted on the UK Biobank cohort (n 449 210). Summary-level data on CVD were obtained from different consortia (n 159 836-977 323). The inverse-variance weighted method (IVW) was the primary outcome, while MR-Egger, weighted median and MR Pleiotropy RESidual Sum and Outlier were used to assess heterogeneity and pleiotropy. We found compelling evidence of a protective causal effect of genetic predisposition towards cheese consumption on myocardial infarction (IVW OR = 0·67; 95 % CI = 0·544, 0·826; P = 1·784 × 10-4) and heart failure (IVW OR = 0·646; 95 % CI = 0·513, 0·814; P = 2·135 × 10-4). Poultry intake was found to be a detrimental factor for hypertension (IVW OR = 4·306; 95 % CI = 2·158, 8·589; P = 3·416 × 10-5), while dried fruit intake was protective against hypertension (IVW OR = 0·473; 95 % CI = 0·348, 0·642; P = 1·683 × 10-6). Importantly, no evidence of pleiotropy was detected. MR estimates provide robust evidence for a causal relationship between genetic predisposition to 20 dietary habits and CVD risk, suggesting that well-planned diets may help prevent and reduce the risk of CVD.

Binding Interaction of Betulinic Acid to α-Glucosidase and Its Alleviation on Postprandial Hyperglycemia.

Inhibiting the intestinal α-glucosidase can effectively control postprandial hyperglycemia for type 2 diabetes mellitus (T2DM) treatment. In the present study, we reported the binding interaction of betulinic acid (BA), a pentacyclic triterpene widely distributed in nature, on α-glucosidase and its alleviation on postprandial hyperglycemia. BA was verified to exhibit a strong inhibitory effect against α-glucosidase with an IC50 value of 16.83 ± 1.16 µM. More importantly, it showed a synergistically inhibitory effect with acarbose. The underlying inhibitory mechanism was investigated by kinetics analysis, surface plasmon resonance (SPR) detection, molecular docking, molecular dynamics (MD) simulation and binding free energy calculation. BA showed a non-competitive inhibition on α-glucosidase. SPR revealed that it had a strong and fast affinity to α-glucosidase with an equilibrium dissociation constant (KD) value of 5.529 × 10-5 M and a slow dissociation. Molecular docking and MD simulation revealed that BA bound to the active site of α-glucosidase mainly due to the van der Waals force and hydrogen bond, and then changed the micro-environment and secondary structure of α-glucosidase. Free energy decomposition indicated amino acid residues such as PHE155, PHE175, HIE277, PHE298, GLU302, TRY311 and ASP347 of α-glucosidase at the binding pocket had strong interactions with BA, while LYS153, ARG210, ARG310, ARG354 and ARG437 showed a negative contribution to binding affinity between BA and α-glucosidase. Significantly, oral administration of BA alleviated the postprandial blood glucose fluctuations in mice. This work may provide new insights into the utilization of BA as a functional food and natural medicine for the control of postprandial hyperglycemia.

Caring ability of nursing students pre- and post-internship: a longitudinal study.

BACKGROUND: Nursing students' internship experiences may significantly impact their caring ability. However, there is a lack of comprehensive evaluation of undergraduate nursing students' caring ability pre-and post-internship in China. This study aimed to explore the differences in the caring ability of undergraduate nursing students before and after internship. METHODS: The sample comprised 305 undergraduate nursing students who had undergone internships during 2018-2020 in three hospitals in Changsha, China. Caring Ability Inventory was used to measure and compare nursing students' caring ability before and after internship. Descriptive statistics and paired t-test were employed to analyze data in SPSS software (version 22.0). RESULTS: A total of 300 students completed the survey (response rate = 98.37%). The overall score of caring ability and scores of cognitive and patience dimensions were higher after internship than before internship (P < 0.05). There was no significant improvement in the courage dimension (P > 0.05). CONCLUSIONS: Caring ability of undergraduate nursing students in China was at a low level, their overall caring ability significantly improved after the internship, indicating a positive relationship between internship and caring ability. Nursing educators and clinical nurses should emphasize the importance of caring ability development in internship planning and encourage nursing students to engage more with patients.

[Birth weight curves of singleton neonates with a gestational age of 24-42 weeks and their regional differences in 11 cities of China: an analysis of 93 720 cases]. / 中国11市93 720例胎龄24~42å‘¨å•èƒŽå„¿å‡ºç”Ÿä½“é‡æ›²çº¿åŠå ¶åœ°åŒºå·®å¼‚ç‰¹å¾.

OBJECTIVES: To develop the birth weight curve of singleton neonates with a gestational age of 24-42 weeks, and to investigate the regional differences of the birth weight curve. METHODS: A total of 11 maternal and child health hospitals with more than 7 000 neonates delivered annually were selected in 11 cities of China (Haikou, Guangzhou, Shenzhen, Liuzhou, Guilin, Quanzhou, Chongqing, Chengdu, Changsha, Ningbo, and Lianyungang), and all live singleton neonates delivered in the 11 hospitals from January 1, 2017 to December 31, 2020 were enrolled for the development of birth weight curves. RESULTS: A total of 93 720 singleton neonates with a gestational age of 24-42 weeks from the 11 cities were included in the study. The reference values of the 3rd-97th percentiles of birth weight of singleton neonates for the total of the 11 cities and for each of the 11 cities were established, and the birth weight percentile curves were drawn. The birth weight curve level of singleton neonates in Shenzhen and Quanzhou was almost the same as the average level of the 11 cities; the birth weight curve level of singleton neonates in Haikou, Guangzhou, Guilin, and Liuzhou was slightly lower than the average level of the 11 cities; the birth weight curve level of singleton neonates in Chongqing, Chengdu, and Changsha was slightly higher than the average level of the 11 cities; the birth weight curve level of singleton neonates in Ningbo and Lianyungang was higher than the average level of the 11 cities. The average birth weight curve level of singleton neonates in the 11 cities were very close to that of China Neonatal Cooperation Network in 2011-2014. CONCLUSIONS: The reference values of the 3rd-97th percentiles of birth weight of singleton neonates for the total of the 11 cities and for each of the 11 cities are developed, which can be used as a reference for evaluating the intrauterine growth of singleton neonates in the region. The level of intrauterine growth of neonates in some cities is different from the national level.

[Birth weights of singleton neonates of 14 Chinese ethnic groups in 11 cities of China]. / 中国11市14ä¸ªæ°‘æ—å•èƒŽå„¿å‡ºç”Ÿä½“é‡ç ”ç©¶.

OBJECTIVES: To develop the birth weight curves of the Chinese Han (26-41 weeks of gestation) and Zhuang (28-41 weeks of gestation) singleton neonates in 11 cities of China, as well as the birth weight means of full-term neonates of 14 Chinese ethnic groups. METHODS: The live singleton neonates who were born in 11 maternal and child health care hospitals from 11 cities of China between January 2017 and December 2020 were classified according to the mother's ethnic group. Birth weight means were calculated for the full-term neonates of each ethnic group. For the Han and Zhuang singleton neonates with a large sample size, the Lambda-Mu-Sigma (LMS) method was used to establish the birth weight percentile curves of the Han and Zhuang singleton neonates with different gestational ages. RESULTS: A total of 105 365 live singleton neonates were included, among whom the Han neonates had the highest number of 84 851 (26-41 weeks of gestation), followed by the Zhuang neonates (12 803 neonates with a gestational age of 28-41 weeks). The neonates of the other Chinese ethnic groups enrolled were live full-term singleton neonates, with a sample size of more than 100 neonates for each ethnic group. The 3rd-97th percentile curves of birth weight were established for the Han singleton neonates with a gestational age of 26-41 weeks and the Zhuang singleton neonates with a gestational age of 28-41 weeks. The birth weight curves of the Han singleton neonates at each gestational age were higher than those of the Zhuang singleton neonates. Birth weight means (3 199-3 499 g) and standard deviations were determined for 14 Chinese ethnic groups, i.e., Li, Mulao, Zhuang, Yao, Dong, Miao, Han, Buyi, Mongolian, Tujia, Yi, Hui, Man, and Korean ethnic groups. The Li ethnic group had the lowest birth weight, followed by the Mulao, Zhuang, Yao, Dong, Miao, Han, Buyi, Mongolian, Tujia, Yi, Hui, Man, and Korean ethnic groups. CONCLUSIONS: The 3rd-97th percentile curves of birth weight are developed for the Han (26-41 weeks of gestation) and Zhuang (28-41 weeks of gestation) singleton neonates in 11 cities of China, and birth weight means are determined for the full-term neonates of 14 Chinese ethnic groups in 11 cities of China, which provides a reference for evaluating the intrauterine growth of neonates in these ethnic groups.

Birth weight curves of twin neonates with a gestational age of 25-40 weeks and their regional differences in 11 cities of China: an analysis of 17 256 cases. / 中国11市17 256例胎龄25~40周双胎儿出生体重曲线及地区差异特征.

OBJECTIVES: To develop the birth weight curve of twin neonates with a gestational age of 25-40 weeks, and to investigate the regional differences of the birth weight curve. METHODS: A total of 11 maternal and child health care hospitals with more than 7 000 neonates delivered annually were selected in 11 cities of China (Haikou, Guangzhou, Liuzhou, Guilin, Quanzhou, Shenzhen, Chongqing, Chengdu, Changsha, Ningbo, and Lianyungang), and all live twin neonates delivered in the 11 hospitals from January 1, 2017 to December 31, 2020 were enrolled for the development of birth weight curves. RESULTS: A total of 17 256 twin neonates with a gestational age of 25-40 weeks from the 11 cities were included in the study. The reference values of the 3rd-97th percentiles of birth weight of twin neonates for the total of the 11 cities and for each of the 11 cities in China were established, and the birth weight percentile curves were drawn. The birth weight curve level of twin neonates in Liuzhou was lower than the average level of the 11 cities; the birth weight curve level of twin neonates in Ningbo was higher than the average level of the 11 cities; the birth weight curve level of twin neonates in Lianyungang was obviously higher than the average level of the 11 cities; the birth weight curve level of twin neonates in other 8 cities was almost the same as the average level of the 11 cities. CONCLUSIONS: The reference values of the 3rd-97th percentiles of birth weight of twin neonates for the total of the 11 cities and for each of the 11 cities are developed, which can be used as a reference for evaluating the intrauterine growth of twin neonates in the region. The level of intrauterine growth of twin neonates in some cities is different from the average level of the 11 cities of China.

Inhibitory effect of triterpenoids from the mushroom Inonotus obliquus against α-glucosidase and their interaction: Inhibition kinetics and molecular stimulations.

Bioassay-guided fractionation led to the isolation of a series of triterpenoids (1-46) including 12 new ones (1-12) from the mushroom Inonotus obliquus. The structures of all the compounds were elucidated by spectroscopic analysis as well as by comparison with literature data. Triterpenoids 1-3, 6, 7, 16, 24, 25, 27, 38, 43, 44 and 46 showed strong α-glucosidase inhibition, with IC50 values from 11.5 to 81.8 µM. Their structure-activity relationships were discussed. Inonotusol F (24) showed the strongest inhibitory activity and it presented noncompetitive inhibition against α-glucosidase. Molecular docking and molecular dynamics stimulation further demonstrated that GLU302 and PHE298 were key amino acids for the inhibition of inonotusol F (24) towards α-glucosidase. This study indicates the vital role of triterpenoids in explaining hypoglycemic effect of Inonotus obliquus and provides important evidence for further development and utilization of this mushroom.

A home-based, post-discharge early intervention program promotes motor development and physical growth in the early preterm infants: a prospective, randomized controlled trial.

BACKGROUND: The implementation of early intervention (EI) in medical settings is time-consuming and resource-intensive, which limits its extensive use. In 2018, the Chinese Eugenics Association developed a home-based, post-discharge EI program. This study aims at evaluating the impact of this EI program on neurodevelopment and physical growth of early preterm infants. METHODS: This study was a prospective, partially blinded, randomized controlled trial (RCT), followed by an open phase. A total of 73 infants born at 28+ 0 ~ 31+ 6 weeks' gestation who were admitted to the Children's Hospital of Chongqing Medical University between December 1, 2019, and June 31, 2020, were enrolled. Another 33 infants were retrospectively recruited as the reference group. Thirty-seven infants randomized in the first early intervention, then standard care (EI-SC) group performed a 30-day EI during RCT period, while 36 infants allocated to SC-EI group were given EI in the following open phase. The test of infant motor performance (TIMP), development quotient (DQ), and anthropometric measures (length, weight, head circumference) were measured at the baseline (T0), termination of the RCT (T1), and termination of the open phase (T2). Repeated measures analysis was performed for comparison among groups. RESULTS: From T0 to T1, both groups had significant improvements in all outcome measures (all p < 0.001). A 30-day EI program was more effective in improving TIMP than standard care (from 53.12 ± 8.79 to 83.50 ± 11.85 in EI-SC group vs from 50.52 ± 8.64 to 75.97 ± 13.44 in SC-EI group, F = 4.232, p = 0.044). EI-SC group also had greater improvements in length, weight, and head circumference than SC-EI group (all p < 0.05). From T0 to T2, there was no significant difference regarding the improvements in all outcomes between the groups (all p > 0.05). At the endpoint of T2, the EI-SC and SC-EI group had similar TIMP and anthropometric measures, but much higher than the reference group (all p < 0.05). CONCLUSIONS: These findings demonstrated that a home-based, post-discharge EI program in this study was a practical approach to promote motor development and physical growth in early preterm infants. TRIAL REGISTRATION: CHICTR, CTR1900028330, registered December 19, 2019, https:// http://www.chictr.org.cn/showproj.aspx?proj=45706.

The molecular architecture of photoreceptor phosphodiesterase 6 (PDE6) with activated G protein elucidates the mechanism of visual excitation.

Photoreceptor phosphodiesterase 6 (PDE6) is the central effector of the visual excitation pathway in both rod and cone photoreceptors, and PDE6 mutations that alter PDE6 structure or regulation can result in several human retinal diseases. The rod PDE6 holoenzyme consists of two catalytic subunits (Pαß) whose activity is suppressed in the dark by binding of two inhibitory γ-subunits (Pγ). Upon photoactivation of rhodopsin, the heterotrimeric G protein (transducin) is activated, resulting in binding of the activated transducin α-subunit (Gtα) to PDE6, displacement of Pγ from the PDE6 active site, and enzyme activation. Although the biochemistry of this pathway is understood, a lack of detailed structural information about the PDE6 activation mechanism hampers efforts to develop therapeutic interventions for managing PDE6-associated retinal diseases. To address this gap, here we used a cross-linking MS-based approach to create a model of the entire interaction surface of Pγ with the regulatory and catalytic domains of Pαß in its nonactivated state. Following reconstitution of PDE6 and activated Gtα with liposomes and identification of cross-links between Gtα and PDE6 subunits, we determined that the PDE6-Gtα protein complex consists of two Gtα-binding sites per holoenzyme. Each Gtα interacts with the catalytic domains of both catalytic subunits and induces major changes in the interaction sites of the Pγ subunit with the catalytic subunits. These results provide the first structural model for the activated state of the transducin-PDE6 complex during visual excitation, enhancing our understanding of the molecular etiology of inherited retinal diseases.

Enhanced production of recombinant proteins in Corynebacterium glutamicum by constructing a bicistronic gene expression system.

BACKGROUND: Corynebacterium glutamicum is a traditional food-grade industrial microorganism, in which an efficient endotoxin-free recombinant protein expression factory is under developing in recent years. However, the intrinsic disadvantage of low recombinant protein expression level is still difficult to be solved. Here, according to the bacteria-specific polycistronic feature that multiple proteins can be translated in one mRNA, efforts have been made to insert a leading peptide gene upstream of target genes as an expression enhancer, and it is found that this can remarkably improve the expression level of proteins under the control of inducible tac promoter in C. glutamicum. RESULTS: In this research, the Escherichia coli (E. coli) tac promoter combined with 24 different fore-cistron sequences were constructed in a bicistronic manner in C. glutamicum. Three strong bicistronic expression vectors were isolated and exhibited high efficiency under different culture conditions. The compatibility of these bicistronic vectors was further validated using six model proteins- aldehyde dehydrogenase (ALDH), alcohol dehydrogenase (ADH), RamA (regulator of acetate metabolism), Bovine interferon-α (BoIFN-α), glycoprotein D protein (gD) of infectious bovine rhinotracheitis virus (IBRV) and procollagen type Ι N-terminal peptide (PΙNP). All examined proteins were highly expressed compared with the original vector with tac promoter. Large-scale production of PΙNP was also performed in fed-batch cultivation, and the highest PΙNP production level was 1.2 g/L. CONCLUSION: In this study, the strength of the inducible tac promoter for C. glutamicum was improved by screening and inserting fore-cistron sequences in front of the target genes. Those vectors with bicistronic expression patterns have strong compatibility for expressing various heterogeneous proteins in high yield. This new strategy could be used to further improve the performance of inducible promoters, achieving double competence of inducible control and high yield.

MicroRNA-93-5p expression in tumor tissue and its tumor suppressor function via targeting programmed death ligand-1 in colorectal cancer.

This work aimed to investigate miR-93-5p expression in tumor tissue and its in vitro effects in colorectal cancer (CRC) by targeting programmed death ligand-1 (PD-L1). MiR-93-5p and PD-L1 expression was detected in CRC and adjacent normal tissues by quantitative real-time polymerase chain reaction and immunohistochemistry. The correlation between miR-93-5p and PD-L1 was validated by a dual-luciferase reporter assay. HCT116 and SW480 cells were divided into blank, miR-NC, miR-93-5p mimics, miR-93-5p inhibitor, PD-L1 small interfering RNA (siRNA) and miR-93-5p inhibitor + PD-L1 siRNA groups, and wound-healing and transwell assays were performed to detect cell migration and invasion, respectively. Protein expression was measured by western blotting. The secretion of cytokines was detected in the CRC cell/T coculture models. MiR-93-5p was downregulated in CRC tissues with upregulated PD-L1. In PD-L1-negative patients, miR-93-5p expression was increased compared with that in PD-L1-positive patients. MiR-93-5p and PD-L1 expression levels were associated with the tumor differentiation, lymphatic metastasis, TNM, Duke's stage, and prognosis of CRC. PD-L1 siRNA weakened the migration and invasion abilities via decreased expression of matrix metalloproteinase-1 (MMP-1), -2, and -9, and these effects were abolished by the miR-93-5p inhibitor. Additionally, anti-PD-L1 upregulated the expressions of interleukin-2 (IL-2), tumor necrosis factor-α (TNF-α), and interferon γ (IFN-γ) in the coculture of T cells with CRC cells, but downregulated the expressions of IL-1ß, IL-10, and TGF-ß. However, these changes were partially reversed by miR-93-5p inhibition. miR-93-5p is expected to be a novel target for CRC treatment since it decreases the migration and invasion, as well as the immune evasion, of CRC cells via targeting PD-L1.

Construction of a 3A system from BioBrick parts for expression of recombinant hirudin variants III in Corynebacterium glutamicum.

Standardized parts can be efficiently assembled into novel biological systems using the three antibiotic (3A) system, ensuring the reusability of components and repeatability of experiments. In this study, we created the 3A expression system for easy construction of gene expression cassettes in Corynebacterium glutamicum (C. glutamicum), which was applied to screen combinations of promoters and signal peptides for improved secreted rhv3 production. We first obtained three strong promoters P2252, Podhi, and PyweA from all of promoters, which drive the highest expression of green fluorescent protein (egfp). The three promoters were then assembled with different signal peptides to generate a series of constructs using the 3A expression system developed in this study, from which the highest activity of rhv3 reached 3187.5 ATU/L of PyweA-CspA-rhv3. Further increased production of rhv3 achieved large-scale fermentation using 5-L jar bioreactor, with the highest rhv3 accumulation 1.21 g/L obtained after 40 h of cultivation, which is higher than 0.95 g/L reported in E. coli. To the best of our knowledge, this is the first report of rhv3 secretory expression in C. glutamicum, which could be applied for the production of other recombinant proteins with significant applications.Key points• We have exploited a 3A system for the genetic manipulation in C. glutamicum.• We constructed element libraries for assembling standard sequence in C. glutamicum.• The secreted expression of rhv3 was realized by 3A system in C. glutamicum.

2-Benzoylbenzofuran derivatives possessing piperazine linker as anticancer agents.

A series of novel 2-benzoylbenzofuran derivatives possessing piperazine linker have been prepared, and their in vitro anticancer activity against a panel of human tumor cell lines by MTT assay were evaluated. The results demonstrated that tertiary amine derivatives exhibited better cytotoxic activity, and SAR study revealed that electron-donating substituents on the phenyl ring of the derivatization functionality contributed to potent anticancer activities. Among them, compounds 6, 9, 11, 18, 23 and 25 displayed both better anti-tumor activity and lower cytotoxic effect on human normal liver cell L02. Further apoptosis analysis showed that compound 18 significantly induced apoptosis in A549 cell, which was considered as the most potent anticancer agent.