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The first example of an acid-promoted difunctionalization of ketones to construct C–P and C–C bonds via a phospha-aldol-elimination is described under metal- and solvent-free conditions.

Various biochemical functions of organisms are performed by protein–protein interactions (PPIs). Therefore, recognition of protein–protein interactions is very important for understanding most life activities, such as DNA replication and transcription, protein synthesis and secretion, signal transduction and metabolism. Although high-throughput technology makes it possible to generate large-scale PPIs data, it requires expensive cost of both time and labor, and leave a risk of high false positive rate. In order to formulate a more ingenious solution, biology community is looking for computational methods to quickly and efficiently discover massive protein interaction data. In this paper, we propose a computational method for predicting PPIs based on a fresh idea of combining orthogonal locality preserving projections (OLPP) and rotation forest (RoF) models, using protein sequence information. Specifically, the protein sequence is first converted into position-specific scoring matrices (PSSMs) containing protein evolutionary information by using the Position-Specific Iterated Basic Local Alignment Search Tool (PSI-BLAST). Then we characterize a protein as a fixed length feature vector by applying OLPP to PSSMs. Finally, we train an RoF classifier for the purpose of identifying non-interacting and interacting protein pairs. The proposed method yielded a significantly better results than existing methods, with 90.07% and 96.09% prediction accuracy on Yeast and Human datasets. Our experiment show the proposed method can serve as a useful tool to accelerate the process of solving key problems in proteomics.

To study the correlation between CT imaging features of acceleration and deceleration brain injury and injury degree.A total of 299 cases with acceleration and deceleration brain injury were collected and divided into acceleration brain injury group and deceleration brain injury group according to the injury mechanism. Subarachnoid hemorrhage (SAH) and Glasgow coma scale (GCS), combined with skull fracture, epidural hematoma (EDH), subdural hematoma (SDH) and brain contusion on the same and opposite sides of the stress point were selected as the screening indexes.EDH on the same side of the stress point, brain contusion on the opposite of the stress point and GCS can be used as key indicators to distinguish acceleration and deceleration injury mechanism. In addition, skull fracture on the same side of the stress point, EDH and SDH on the opposite of the stress point and SAH were relatively weak indicators in distinguishing acceleration and deceleration injury mechanism.

To apply the convolutional neural network (CNN) Inception_v3 model in automatic identification of acceleration and deceleration injury based on CT images of brain, and to explore the application prospect of deep learning technology in forensic brain injury mechanism inference.CT images from 190 cases with acceleration and deceleration brain injury were selected as the experimental group, and CT images from 130 normal brain cases were used as the control group. The above-mentioned 320 imaging data were divided into training validation dataset and testing dataset according to random sampling method. The model classification performance was evaluated by the accuracy rate, precision rate, recall rate,In the training process and validation process, the accuracy rate of the model to classify acceleration injury, deceleration injury and normal brain was 99.00% and 87.21%, which met the requirements. The optimized model was used to test the data of the testing dataset, the result showed that the accuracy rate of the model in the test set was 87.18%, and the precision rate, recall rate,Inception_v3 model has potential application value in distinguishing acceleration and deceleration injury based on brain CT images, and is expected to become an auxiliary tool to infer the mechanism of head injury.

Symbionts can regulate animal reproduction in multiple ways, but the underlying physiological and biochemical mechanisms remain largely unknown. The presence of multiple lineages of maternally inherited, intracellular symbionts (the primary and secondary symbionts) in terrestrial arthropods is widespread in nature. However, the biological, metabolic, and evolutionary role of co-resident secondary symbionts for hosts is poorly understood. The bacterial symbionts Hamiltonella and Arsenophonus have very high prevalence in two globally important pests, the whiteflies Bemisia tabaci and Trialeurodes vaporariorum, respectively. Both symbionts coexist with the primary symbiont Portiera in the same host cell (bacteriocyte) and are maternally transmitted. We found that elimination of both Hamiltonella and Arsenophonous by antibiotic treatment reduced the percentage of female offspring in whiteflies. Microsatellite genotyping and cytogenetic analysis revealed that symbiont deficiency inhibited fertilization in whiteflies, leading to more haploid males with one maternal allele, which is consistent with distorted sex ratio in whiteflies. Quantification of essential amino acids and B vitamins in whiteflies indicated that symbiont deficiency reduced B vitamin levels, and dietary B vitamin supplementation rescued fitness of whiteflies. This study, for the first time, conclusively demonstrates that these two intracellular symbionts affect sex ratios in their whitefly hosts by regulating fertilization and supplying B vitamins. Our results reveal that both symbionts have the convergent function of regulating reproduction in phylogenetically-distant whitefly species. The 100% frequency, the inability of whiteflies to develop normally without their symbiont, and rescue with B vitamins suggests that both symbionts may be better considered co-primary symbionts.

Biliary strictures after liver transplantation (LT) remain clinically arduous and challenging situations, and endoscopic retrograde cholangiopancreatography (ERCP) has been considered as the gold standard for the management of biliary strictures after LT. Nevertheless, in the treatment of biliary strictures after LT with ERCP, many studies show that there is a large variation in diagnostic accuracy and therapeutic success rate. Digital single-operator peroral cholangioscopy (DSOC) is considered a valuable diagnostic modality for indeterminate biliary strictures.To evaluate DSOC in addition to ERCP for management of biliary strictures after LT.Nineteen patients with duct-to-duct biliary reconstruction who underwent ERCP for suspected biliary complications between March 2019 and March 2020 at Beijing Chaoyang Hospital, Capital Medical University, were consecutively enrolled in this observational study. After evaluating bile ducts using fluoroscopy, cholangioscopy using a modern digital single-operator cholangioscopy system (SpyGlass DS™) was performed during the same procedure with patients under conscious sedation. All patients received peri-interventional antibiotic prophylaxis. Biliary strictures after LT were classified according to the manifestations of choledochoscopic strictures and the manifestations of transplanted hepatobiliary ducts.Twenty-one biliary strictures were found in a total of 19 patients, among which anastomotic strictures were evident in 18 (94.7%) patients, while non-anastomotic strictures in 2 (10.5%), and space-occupying lesions in 1 (5.3%). Stones were found in 11 (57.9%) and loose sutures in 8 (42.1%). A benefit of cholangioscopy was seen in 15 (78.9%) patients. Cholangioscopy was crucial for selective guidewire placement prior to planned intervention in 4 patients. It was instrumental in identifying biliary stone and/or loose sutures in 9 patients in whom ERCP failed. It also provided a direct vision for laser lithotripsy. A space-occupying lesion in the bile duct was diagnosed by cholangioscopy in one patient. Patients with biliary stricture after LT displayed four types: (A) mild inflammatory change (DSOC can provide important diagnostic information, helping plan and perform interventional procedures in LT-related biliary strictures.

BACKGROUND This retrospective study from 2 centers in Beijing, China aimed to assess the safety and efficacy of endoscopic radiofrequency therapy under direct vision in 59 patients with gastroesophageal reflux disease (GERD) using the gastroesophageal reflux disease questionnaire (GerdQ). MATERIAL AND METHODS Fifty-nine GERD patients who underwent endoscopic radiofrequency treatment were included. Patients were divided into 2 groups: the endoscopic radiofrequency therapy under direct vision group and the non-direct vision radiofrequency therapy group. Indicators such as GerdQ score, lower esophageal sphincter (LES) pressure, DeMeester score, acid exposure time, and proton pump inhibitors (PPIs) use were collected before and after radiofrequency treatment. Postoperative complications were also recorded. The efficacy and safety of endoscopic radiofrequency therapy under direct vision were evaluated by comparing the indicators of patients in the 2 groups. RESULTS At 3 months after radiofrequency treatment, patients in the endoscopic radiofrequency therapy under direct vision group improved significantly in GerdQ score, decreased from 11.0 (10.0, 12.0) to 6.0 (6.0, 8.0), better than patients in the non-direct vision radiofrequency therapy group, and the better improvements remained at 12 months after the procedure (P0.05). At 6 months after treatment, patients in the endoscopic radiofrequency therapy under direct vision group had significant improvements in LES pressure, which increased from 8.15 (3.18, 12.88) mmHg to 15.20 (10.25, 27.03) mmHg (P0.05). There were no severe complications in our trial. CONCLUSIONS When compared with non-visualized endoscopic radiofrequency therapy, treatment under direct vision was safer and improved the GerdQ score and LES pressure at up to 12 months.

Nutritional symbionts are restricted to specialized host cells called bacteriocytes in various insect orders. These symbionts can provide essential nutrients to the host. However, the cellular mechanisms underlying the regulation of these insect-symbiont metabolic associations remain largely unclear. The whitefly Bemisia tabaci MEAM1 hosts “Candidatus Portiera aleyrodidarum” (here, “Ca. Portiera”) and “Candidatus Hamiltonella defensa” (here, “Ca. Hamiltonella”) bacteria in the same bacteriocyte. In this study, the induction of autophagy by chemical treatment and gene silencing decreased symbiont titers and essential amino acid (EAA) and B vitamin contents. In contrast, the repression of autophagy in bacteriocytes via Atg8 silencing increased symbiont titers, and amino acid and B vitamin contents. Furthermore, dietary supplementation with non-EAAs or B vitamins alleviated autophagy in whitefly bacteriocytes, elevated TOR (target of rapamycin) expression, and increased symbiont titers. TOR silencing restored symbiont titers in whiteflies after dietary supplementation with B vitamins. These data suggest that “Ca. Portiera” and “Ca. Hamiltonella” evade autophagy of the whitefly bacteriocytes by activating the TOR pathway via providing essential nutrients. Taken together, we demonstrate that autophagy plays a critical role in regulating the metabolic interactions between the whitefly and two intracellular symbionts. Therefore, this study reveals that autophagy is an important cellular basis for bacteriocyte evolution and symbiosis persistence in whiteflies. The whitefly symbiosis unravels the interactions between cellular and metabolic functions of bacteriocytes. IMPORTANCE Nutritional symbionts, which are restricted to specialized host cells called bacteriocytes, can provide essential nutrients for many hosts. However, the cellular mechanisms of regulation of animal-symbiont metabolic associations have been largely unexplored. Here, using the whitefly-“Ca. Portiera”/“Ca. Hamiltonella” endosymbiosis, we demonstrate autophagy regulates the symbiont titers and thereby alters the essential amino acid and B vitamin contents. For persistence in the whitefly bacteriocytes, “Ca. Portiera” and “Ca. Hamiltonella” alleviate autophagy by activating the TOR (target of rapamycin) pathway through providing essential nutrients. Therefore, we demonstrate that autophagy plays a critical role in regulating the metabolic interactions between the whitefly and two intracellular symbionts. This study also provides insight into the cellular basis of bacteriocyte evolution and symbiosis persistence in the whitefly. The mechanisms underlying the role of autophagy in whitefly symbiosis could be widespread in many insect nutritional symbioses. These findings provide a new avenue for whitefly control via regulating autophagy in the future.

The Zanhuang Complex is located in central section of the Trans-North China Orogen (TNCO) in the North China Craton (NCC) with complicated tectonic history. The formation timing (Neoarchean or Paleoproterozoic) of the Guandu Group or Central Zanhuang Domain (CZD) is still under debate, while this question is critical for understanding the tectonic evolution of the Zanhuang Complex and the TNCO. The mafic rocks in the Guandu Group (or CZD) can be subdivided into three different types by petrological, geochronological, structural and petrogenetic differences. Type 1 consists of “pillow” epidosites and amphibolites, located at the west part of the Guandu Group; type 2 dominated by amphibolites and interbedding with various sedimentary rocks, located at the east part; and type 3 consists of mafic dikes beyond the scope of this paper. Type 1 mafic rock yielded zircon U-Pb age of 2501 ± 12 Ma which constrains it formed at Neoarchean with older Nd TDM ages (2.8–3.0 Ga). Interbedded sedimentary rocks with younger than 2.1 Ga detrital zircon ages, and the much younger Nd TDM model ages (2.2–2.3 Ga) of the amphibolites from type 2, together suggest that the type 2 mafic rocks and associated sedimentary rocks may have formed at Paleoproterozoic. Thus, we propose that the so-called Guandu Group is not a single and unitary tectonic-lithological unit but consists of at least two different volcanic-sedimentary successions formed at different times and pieced together by later tectonic event (s). A new two-period tectonic events model is proposed here. Before 2.5 Ga, the western margin of the Eastern Block deposited a series of volcanic-sedimentary rocks (type 1). At ∼2.5 Ga, the Fuping arc (including the Western Zanhuang Domain) amalgamated with the Eastern Block by arc-continent collision. After a quiescent period, it underwent ∼2.1 Ga extension and rifting. Later, the rift evolved into a small ocean basin with the deposition of volcanic-sedimentary sequences (type 2), then closed through west-dipping subduction and collision at 1.9–1.85 Ga, resulting in the final amalgamation of the NCC and the widespread deformation and metamorphism in the Zanhuang Complex as well as the whole TNCO.

Horizontal gene transfer is widespread in insects bearing intracellular symbionts. Horizontally transferred genes (HTGs) are presumably involved in amino acid synthesis in sternorrhynchan insects. However, their role in insect-symbiont interactions remains largely unknown. We found symbionts Portiera, Hamiltonella and Rickettsia possess most genes involved in lysine synthesis in the whitefly Bemisia tabaci MEAM1 although their genomes are reduced. Hamiltonella maintains a nearly complete lysine synthesis pathway. In contrast, Portiera and Rickettsia require the complementation of whitefly HTGs for lysine synthesis and have lysE, encoding a lysine exporter. Furthermore, each horizontally transferred lysine gene of ten B. tabaci cryptic species shares an evolutionary origin. We demonstrated that Hamiltonella did not alter the titers of Portiera and Rickettsia or lysine gene expression of Portiera, Rickettsia and whiteflies. Hamiltonella also did not impact on lysine levels or protein localization in bacteriocytes harboring Portiera and ovaries infected with Rickettsia. Complementation with whitefly lysine synthesis HTGs rescued E. coli lysine gene knockout mutants. Silencing whitefly lysA in whiteflies harboring Hamiltonella reduced lysine levels, adult fecundity and titers of Portiera and Rickettsia without influencing the expression of Hamiltonella lysA. Furthermore, silencing whitefly lysA in whiteflies lacking Hamiltonella reduced lysine levels, adult fecundity and titers of Portiera and Rickettsia in ovarioles. Therefore, we, for the first time, demonstrated an essential amino acid lysine synthesized through HTGs is important for whitefly reproduction and fitness of both obligate and facultative symbionts, and it illustrates the mutual dependence between whitefly and its two symbionts. Collectively, this study reveals that acquisition of horizontally transferred lysine genes contributes to coadaptation and coevolution between B. tabaci and its symbionts., Author summary Revealing which molecules are exchanged between host and symbionts will illuminate how host and bacterial symbiont establish beneficial relationships. Horizontally transferred genes (HTGs) presumably complement the missing genes involved in synthesis of essential amino acids (EAAs) in symbionts of sternorrhynchan insects. We demonstrate that whitefly HTGs can cooperate with Portiera and Rickettsia for lysine synthesis. The lysine synthesized through HTGs impacts both whitefly reproduction and symbiont fitness. Taken together, we reveal that horizontally acquired lysine genes underlie the basis for the mutual dependence between whitefly and two intracellular symbionts. Therefore, our study demonstrates the critical role of HTGs in the synthesis of EAAs and their function in insect-symbiont interactions and coevolution.

It is well known that a dual trigger treatment can improve clinical outcomes of in vitro fertilization (IVF) in high or normal ovarian responders. However, it is not clear whether dual triggering also benefits patients with diminished ovarian reserve (DOR). The aim of this study was to investigate whether a dual trigger treatment of gonadotropin-releasing hormone (GnRH) agonist combined with human chorionic gonadotropin (hCG) for final follicular maturation improves the cumulative live birth rate (CLBR) during the GnRH-antagonist cycle in patients with DOR.This retrospective study included patients with DOR who received a GnRH-antagonist protocol during IVF and intracytoplasmic sperm injection (IVF-ICSI) cycles at Peking University People's Hospital from January 1, 2017 through December 31, 2017. Oocyte maturation was triggered by GnRH combined with hCG (n=110) or hCG alone (n=71). Embryos were transferred on the third day after oocyte retrieval or during a subsequent freeze-thaw cycle. Patients were followed up for 3 years.The dual trigger treatment did not affect CLBR, which is an overall determinant of the success rate of assisted reproductive technology (ART). Women in the dual trigger group had significantly higher rates of fertilization than those in the hCG group (90.1% vs. 83.9%, P=0.040).Dual trigger with GnRH agonist and hCG did not improve CLBR in patients with DOR, but did slightly improve fertilization rate, oocyte count, and embryo quality.

To investigate the infection of reproductive Mycoplasma genitalium (MG) detected by real-time fluorescence constant-temperature simultaneous amplification and testing (SAT) of nucleic acid among patients present at the clinics of urology, gynecology or venereal diseases.We retrospectively analyzed the clinical data on 5 711 patients with suspected genitourinary tract (GUT) infection present at the clinics of urology, gynecology or sexually transmitted diseases in Hangzhou Third People's Hospital, Shaoxing People's Hospital and General Hospital of Eastern Theater Command from January 2018 to December 2018. The patients were aged 16－73 (38.77 ± 11.32) years, 3 425 males and 2 286 females. We collected urine samples from 3 666, GUT secretion samples from 2 095, and both urine and GUT samples from 50 of the patients. Using the SAT technique, we detected the infections of MG, Ureaplasma urealyticum (UU), Chlamydia trachomatis (CT), and Neisseria gonorrhoeae (NG) in the patients.Of the 5 711 patients, 294 (5.15%) were found MG-positive, with a significantly higher positive rate in the males than in the females (5.96% ［206/3 425］ vs 3.85% ［88/2 286］, P0.05). The laboratory results with the urine and GUT secretion samples from 50 of the cases showed a consistency rate of 100%. Simple MG infection accounted for 52.04% in the 294 MG-positive cases, 63.11% in the 206 MG-positive males, and 26.13% in the 88 females, with a significantly higher positive rate in the males than in the females (P0.05). MG combined with UU infection had the highest rate among the mixed infections in both the males and females and in those aged ≤20 years, even higher in the females than in the males (P0.05) and in the ≤20-year-old males than in the ≤20-year-old females (8.65% ［9/104］ vs 5.13% ［4/78］, P0.05). There were statistically significant differences in the MG-positive rate among different age groups (χ2 = 32.74, P0.05).Among patients with suspected GUT infection, the MG-positive rate is higher in men than in women, with MG + UU-positive as the most common mixed infection, and it decreases with the increase of age. The results of SAT of urine and GUT secretion have a high consistency rate.

Abundant life activities are maintained by various biomolecule relationships in human cells. However, many previous computational models only focus on isolated objects, without considering that cell is a complete entity with ample functions. Inspired by holism, we constructed a Molecular Associations Network (MAN) including 9 kinds of relationships among 5 types of biomolecules, and a prediction model called MAN-GF. More specifically, biomolecules can be represented as vectors by the algorithm called biomarker2vec which combines 2 kinds of information involved the attribute learned by k-mer, etc and the behavior learned by Graph Factorization (GF). Then, Random Forest classifier is applied for training, validation and test. MAN-GF obtained a substantial performance with AUC of 0.9647 and AUPR of 0.9521 under 5-fold Cross-validation. The results imply that MAN-GF with an overall perspective can act as ancillary for practice. Besides, it holds great hope to provide a new insight to elucidate the regulatory mechanisms., Guo et al. construct a large scale Molecular Associations Network (MAN) including 9 kinds of associations among 5 types of biomolecules, namely protein, miRNA, lncRNA, disease and drug. They further propose a computational model, MAN-GF, that can predict links between these biomolecules and displays a substantial performance under 5-fold cross validation.

Background The interactions between non-coding RNAs (ncRNA) and proteins play an essential role in many biological processes. Several high-throughput experimental methods have been applied to detect ncRNA-protein interactions. However, these methods are time-consuming and expensive. Accurate and efficient computational methods can assist and accelerate the study of ncRNA-protein interactions. Results In this work, we develop a stacking ensemble computational framework, RPI-SE, for effectively predicting ncRNA-protein interactions. More specifically, to fully exploit protein and RNA sequence feature, Position Weight Matrix combined with Legendre Moments is applied to obtain protein evolutionary information. Meanwhile, k-mer sparse matrix is employed to extract efficient feature of ncRNA sequences. Finally, an ensemble learning framework integrated different types of base classifier is developed to predict ncRNA-protein interactions using these discriminative features. The accuracy and robustness of RPI-SE was evaluated on three benchmark data sets under five-fold cross-validation and compared with other state-of-the-art methods. Conclusions The results demonstrate that RPI-SE is competent for ncRNA-protein interactions prediction task with high accuracy and robustness. It’s anticipated that this work can provide a computational prediction tool to advance ncRNA-protein interactions related biomedical research.

Some symbiotic microbes are restricted to specialized host cells called bacteriocytes. However, the molecular and cellular mechanisms underlying the development of bacteriocytes are largely obscure. We find that maternally inherited bacteriocytes proliferate in adult females but degenerate in adult males of the whitefly Bemisia tabaci. Single-cell transcriptomics and immunohistochemistry reveal that cell division only occurs in the bacteriocytes of adult females, whereas autophagy and apoptosis are induced in the bacteriocytes of adult males. A transcription factor, Adf-1, enriched in bacteriocytes, is highly expressed in female bacteriocytes relative to male bacteriocytes. Silencing Adf-1 reduces the bacteriocyte number and Portiera titer and activates autophagy and apoptosis in females. The differential dynamics of both cell division and death in bacteriocytes and distinct expression of Adf-1 in bacteriocytes between whitefly sexes underlie the sexual differentiation of bacteriocyte development. Our study reveals that insect sex affects the development of bacteriocytes by cellular and molecular remodeling.

Materials with tunable Poisson’s ratio and lightweight are important to engineering applications. Based on the traditional star-shaped structure, a novel 2D arc-star-shaped structure (2D-AS) with tunable Poisson’s ratio is designed in this paper. Moreover, the 2D-AS has also been generalized to two different 3D configurations, including the 3D-ATC (3D configuration of the arc-star-shaped of traditional connection) and the 3D-ANC (3D configuration of the arc-star-shaped of new connection). The effective Poisson’s ratios and the effective Young’s moduli of the 2D-AS, 3D-ATC, and 3D-ANC are analyzed using the energy method and numerical simulations. The theoretical results and the numerical results are verified by the compression test. The results indicate that the effective Poisson’s ratios of the proposed structures can be programmed from positive to negative by changing the geometry coefficients. The properties of the structures present promising potentials for applications in the fields of machinery, encompassing biomedicine, and electronic devices.

In this paper, the complete electromechanical properties of the cellular-materials-based piezoelectric metamaterial are obtained by using micromechanical modeling method on the basis of the finite element. This study considers the piezoelectric star-shaped cellular structures (PSSCSs) with three connection modes (with symmetric interconnects, with asymmetric interconnects, and without any interconnects) and two poling directions (longitudinal and transverse). The representative volume units of three types of PSSCSs are established respectively, and the finite element analysis is implemented to the effect of different structural length parameters on the effective electromechanical response and the applicability of specific engineering applications. Compared with the monolithic piezoelectric materials, the PSSCSs show an enhanced performance combination. Besides, the results show that PSSCSs have adjustable electromechanical properties.

Protein-protein interactions (PPIs), as an important molecular process within cells, are of pivotal importance in the biochemical function of cells. Although high-throughput experimental techniques have matured, enabling researchers to detect large amounts of PPIs, it has unavoidable disadvantages, such as having a high cost and being time consuming. Recent studies have demonstrated that PPIs can be efficiently detected by computational methods. Therefore, in this study, we propose a novel computational method to predict PPIs using only protein sequence information. This method was developed based on a deep learning algorithm-stacked sparse autoencoder (SSAE) combined with a Legendre moment (LM) feature extraction technique. Finally, a probabilistic classification vector machine (PCVM) classifier is used to implement PPI prediction. The proposed method was performed on human, unbalanced-human, H. pylori, and S. cerevisiae datasets with 5-fold cross-validation and yielded very high predictive accuracies of 98.58%, 97.71%, 93.76%, and 96.55%, respectively. To further evaluate the performance of our method, we compare it with the support vector machine- (SVM-) based method. The experimental results indicate that the PCVM-based method is obviously preferable to the SVM-based method. Our results have proven that the proposed method is practical, effective, and robust.