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1.
J Org Chem ; 89(12): 8531-8536, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38838346

RESUMEN

An effective multicomponent reaction for the synthesis of 4-phosphorylated 4H-chromenes via a tandem phosphorylation/alkylation/cyclization/dehydration sequence with water as the only byproduct was developed. Extensive mechanistic investigations involving in situ NMR experiments, time control experiments, and in situ HRMS experiment allowed us to elucidate the order of each subreaction to arrive at a complete understanding of the underlying mechanism of this multicomponent reaction. Mechanistic data confirm that the reaction begins with a phospha-aldol-elimination, followed by addition of a ketone enolate, intermolecular alkylation, intramolecular cyclization, and dehydration under acidic conditions.

2.
World J Clin Cases ; 12(17): 2976-2982, 2024 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-38898850

RESUMEN

BACKGROUND: Diabetic foot ulcers (DFUs) are a common complication of diabetes, often leading to severe infections, amputations, and reduced quality of life. The current standard treatment protocols for DFUs have limitations in promoting efficient wound healing and preventing complications. A comprehensive treatment approach targeting multiple aspects of wound care may offer improved outcomes for patients with DFUs. The hypothesis of this study is that a comprehensive treatment protocol for DFUs will result in faster wound healing, reduced amputation rates, and improved overall patient outcomes compared to standard treatment protocols. AIM: To compare the efficacy and safety of a comprehensive treatment protocol for DFUs with those of the standard treatment protocol. METHODS: This retrospective study included 62 patients with DFUs, enrolled between January 2022 and January 2024, randomly assigned to the experimental (n = 32) or control (n = 30) group. The experimental group received a comprehensive treatment comprising blood circulation improvement, debridement, vacuum sealing drainage, recombinant human epidermal growth factor and anti-inflammatory dressing, and skin grafting. The control group received standard treatment, which included wound cleaning and dressing, antibiotics administration, and surgical debridement or amputation, if necessary. Time taken to reduce the white blood cell count, number of dressing changes, wound healing rate and time, and amputation rate were assessed. RESULTS: The experimental group exhibited significantly better outcomes than those of the control group in terms of the wound healing rate, wound healing time, and amputation rate. Additionally, the comprehensive treatment protocol was safe and well tolerated by the patients. CONCLUSION: Comprehensive treatment for DFUs is more effective than standard treatment, promoting granulation tissue growth, shortening hospitalization time, reducing pain and amputation rate, improving wound healing, and enhancing quality of life.

3.
Brief Bioinform ; 25(2)2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38271483

RESUMEN

The advent of single-cell sequencing technologies has revolutionized cell biology studies. However, integrative analyses of diverse single-cell data face serious challenges, including technological noise, sample heterogeneity, and different modalities and species. To address these problems, we propose scCorrector, a variational autoencoder-based model that can integrate single-cell data from different studies and map them into a common space. Specifically, we designed a Study Specific Adaptive Normalization for each study in decoder to implement these features. scCorrector substantially achieves competitive and robust performance compared with state-of-the-art methods and brings novel insights under various circumstances (e.g. various batches, multi-omics, cross-species, and development stages). In addition, the integration of single-cell data and spatial data makes it possible to transfer information between different studies, which greatly expand the narrow range of genes covered by MERFISH technology. In summary, scCorrector can efficiently integrate multi-study single-cell datasets, thereby providing broad opportunities to tackle challenges emerging from noisy resources.

4.
RSC Adv ; 14(6): 3757-3760, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38268541

RESUMEN

An efficient method has been developed for reacting dialkyl H-phosphonates or diarylphosphine oxides with alcohols for constructing C-P bonds. This reaction was catalyzed by Lewis acid and involved nucleophilic substitution. A series of diphenylphosphonates and diphenylphosphine oxides were obtained, from the phosphorylation of alcohols, with good-to-excellent yields.

5.
BMC Bioinformatics ; 24(1): 481, 2023 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-38104057

RESUMEN

BACKGROUND: The rapid emergence of single-cell RNA-seq (scRNA-seq) data presents remarkable opportunities for broad investigations through integration analyses. However, most integration models are black boxes that lack interpretability or are hard to train. RESULTS: To address the above issues, we propose scInterpreter, a deep learning-based interpretable model. scInterpreter substantially outperforms other state-of-the-art (SOTA) models in multiple benchmark datasets. In addition, scInterpreter is extensible and can integrate and annotate atlas scRNA-seq data. We evaluated the robustness of scInterpreter in a variety of situations. Through comparison experiments, we found that with a knowledge prior, the training process can be significantly accelerated. Finally, we conducted interpretability analysis for each dimension (pathway) of cell representation in the embedding space. CONCLUSIONS: The results showed that the cell representations obtained by scInterpreter are full of biological significance. Through weight sorting, we found several new genes related to pathways in PBMC dataset. In general, scInterpreter is an effective and interpretable integration tool. It is expected that scInterpreter will bring great convenience to the study of single-cell transcriptomics.


Asunto(s)
Leucocitos Mononucleares , Análisis de Expresión Génica de una Sola Célula , Análisis de Secuencia de ARN/métodos , Leucocitos Mononucleares/metabolismo , Análisis de la Célula Individual/métodos , Perfilación de la Expresión Génica/métodos , Análisis por Conglomerados
6.
J Org Chem ; 88(23): 16216-16228, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37967376

RESUMEN

An effective and economical acid-promoted three-component reaction for the construction of C-P and C-C bonds for the synthesis of γ-ketophosphine oxides with water as the only byproduct was developed. Detailed mechanistic experiments confirmed that the reaction proceeds by phospha-aldol elimination, in which a benzylic carbocation is generated from the phosphorylation of aldehydes, which then reacts with ketone enolates under acidic conditions.

7.
Fa Yi Xue Za Zhi ; 39(2): 186-192, 2023 Apr 25.
Artículo en Inglés, Chino | MEDLINE | ID: mdl-37277382

RESUMEN

OBJECTIVES: To survey the development status and actual needs of virtual autopsy technology in China and to clarify the applicability of forensic virtual autopsy laboratory accreditation. METHODS: The questionnaire was set up included three aspects:(1) the current status of virtual autopsy technology development; (2) the accreditation elements such as personnel, equipment, entrustment and acceptance, methods, environmental facilities; (3) the needs and suggestions of practicing institutions. A total of 130 forensic pathology institutions were surveyed by online participation through the Questionnaire Star platform. RESULTS: Among the 130 institutions, 43.08% were familiar with the characteristics of virtual autopsy technology, 35.38% conducted or received training in virtual autopsy, and 70.77% have establishment needs (including maintenance). Relevant elements were suitable for laboratory accreditation. CONCLUSIONS: Virtual autopsy identification has gained social recognition. There is a demand for accreditation of forensic virtual autopsy laboratory. After the preliminary assessment, considering the characteristics and current situation of this technology, China National Accreditation Service for Conformity Assessment (CNAS) can first carry out the accreditation pilot of virtual autopsy project at large comprehensive forensic institutions with higher identification capability, and then CNAS can popularize the accreditation in a wide range when the conditions are suitable.


Asunto(s)
Autopsia , Patologia Forense , Laboratorios , Medicina Legal , Acreditación , Laboratorios/normas , China
8.
BMC Bioinformatics ; 23(Suppl 7): 518, 2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36457083

RESUMEN

BACKGROUND: Self-interacting proteins (SIPs), two or more copies of the protein that can interact with each other expressed by one gene, play a central role in the regulation of most living cells and cellular functions. Although numerous SIPs data can be provided by using high-throughput experimental techniques, there are still several shortcomings such as in time-consuming, costly, inefficient, and inherently high in false-positive rates, for the experimental identification of SIPs even nowadays. Therefore, it is more and more significant how to develop efficient and accurate automatic approaches as a supplement of experimental methods for assisting and accelerating the study of predicting SIPs from protein sequence information. RESULTS: In this paper, we present a novel framework, termed GLCM-WSRC (gray level co-occurrence matrix-weighted sparse representation based classification), for predicting SIPs automatically based on protein evolutionary information from protein primary sequences. More specifically, we firstly convert the protein sequence into Position Specific Scoring Matrix (PSSM) containing protein sequence evolutionary information, exploiting the Position Specific Iterated BLAST (PSI-BLAST) tool. Secondly, using an efficient feature extraction approach, i.e., GLCM, we extract abstract salient and invariant feature vectors from the PSSM, and then perform a pre-processing operation, the adaptive synthetic (ADASYN) technique, to balance the SIPs dataset to generate new feature vectors for classification. Finally, we employ an efficient and reliable WSRC model to identify SIPs according to the known information of self-interacting and non-interacting proteins. CONCLUSIONS: Extensive experimental results show that the proposed approach exhibits high prediction performance with 98.10% accuracy on the yeast dataset, and 91.51% accuracy on the human dataset, which further reveals that the proposed model could be a useful tool for large-scale self-interacting protein prediction and other bioinformatics tasks detection in the future.


Asunto(s)
Evolución Biológica , Biología Computacional , Humanos , Secuencia de Aminoácidos , Posición Específica de Matrices de Puntuación , Leucocitos , Saccharomyces cerevisiae/genética
9.
Curr Med Sci ; 42(5): 1066-1070, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35997911

RESUMEN

OBJECTIVE: 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. METHODS: 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. RESULTS: 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). CONCLUSION: 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.


Asunto(s)
Enfermedades del Ovario , Reserva Ovárica , Masculino , Embarazo , Humanos , Femenino , Inyecciones de Esperma Intracitoplasmáticas/métodos , Tasa de Natalidad , Inducción de la Ovulación/métodos , Índice de Embarazo , Estudios Retrospectivos , Semen , Fertilización In Vitro/métodos , Antagonistas de Hormonas/farmacología , Antagonistas de Hormonas/uso terapéutico , Gonadotropina Coriónica/farmacología , Gonadotropina Coriónica/uso terapéutico , Hormona Liberadora de Gonadotropina , Oocitos
10.
Fa Yi Xue Za Zhi ; 38(2): 217-222, 2022 Apr 25.
Artículo en Inglés, Chino | MEDLINE | ID: mdl-35899510

RESUMEN

OBJECTIVES: To study the correlation between CT imaging features of acceleration and deceleration brain injury and injury degree. METHODS: 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. χ2 test was used for primary screening, and binary logistic regression analysis was used for secondary screening. The indexes with the strongest correlation in acceleration and deceleration injury mechanism were selected. RESULTS: χ2 test showed that skull fracture and EDH on the same side of the stress point; EDH, SDH and brain contusion on the opposite of the stress point; SAH, GCS were correlated with acceleration and deceleration injury (P<0.05). According to binary logistic regression analysis, the odds ratio (OR) of EDH on the same side of the stress point was 2.697, the OR of brain contusion on the opposite of the stress point was 0.043 and the OR of GCS was 0.238, suggesting there was statistically significant (P<0.05). CONCLUSIONS: 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.


Asunto(s)
Contusión Encefálica , Lesiones Encefálicas , Hematoma Epidural Craneal , Fracturas Craneales , Heridas no Penetrantes , Lesiones Encefálicas/diagnóstico por imagen , Hematoma Subdural/diagnóstico por imagen , Hematoma Subdural/etiología , Humanos , Modelos Logísticos , Fracturas Craneales/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Heridas no Penetrantes/diagnóstico por imagen
11.
Fa Yi Xue Za Zhi ; 38(2): 223-230, 2022 Apr 25.
Artículo en Inglés, Chino | MEDLINE | ID: mdl-35899511

RESUMEN

OBJECTIVES: 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. METHODS: 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, F1-value and AUC value. RESULTS: 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, F1-score and AUC of the model to recognize acceleration injury were 84.38%, 90.00%, 87.10% and 0.98, respectively, to recognize deceleration injury were 86.67%, 72.22%, 78.79% and 0.92, respectively, to recognize normal brain were 88.57%, 89.86%, 89.21% and 0.93, respectively. CONCLUSIONS: 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.


Asunto(s)
Lesiones Encefálicas , Aprendizaje Profundo , Encéfalo/diagnóstico por imagen , Humanos , Redes Neurales de la Computación
12.
World J Gastrointest Oncol ; 14(5): 1037-1049, 2022 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-35646282

RESUMEN

BACKGROUND: 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. AIM: To evaluate DSOC in addition to ERCP for management of biliary strictures after LT. METHODS: 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. RESULTS: 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 (n = 9); (B) acute inflammatory change edema, ulceration, and sloughing (n = 3); (C) chronic inflammatory change; and (D) acute suppurative change. Complications were seen in three patients with post-interventional cholangitis and another three with hyperamylasemia. CONCLUSION: DSOC can provide important diagnostic information, helping plan and perform interventional procedures in LT-related biliary strictures.

13.
Cell Rep ; 38(9): 110455, 2022 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-35235797

RESUMEN

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.


Asunto(s)
Hemípteros , Animales , Diferenciación Celular , Femenino , Hemípteros/metabolismo , Masculino , Simbiosis , Factores de Transcripción/metabolismo
15.
BMC Bioinformatics ; 22(Suppl 5): 622, 2022 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-35317723

RESUMEN

BACKGROUND: lncRNAs play a critical role in numerous biological processes and life activities, especially diseases. Considering that traditional wet experiments for identifying uncovered lncRNA-disease associations is limited in terms of time consumption and labor cost. It is imperative to construct reliable and efficient computational models as addition for practice. Deep learning technologies have been proved to make impressive contributions in many areas, but the feasibility of it in bioinformatics has not been adequately verified. RESULTS: In this paper, a machine learning-based model called LDACE was proposed to predict potential lncRNA-disease associations by combining Extreme Learning Machine (ELM) and Convolutional Neural Network (CNN). Specifically, the representation vectors are constructed by integrating multiple types of biology information including functional similarity and semantic similarity. Then, CNN is applied to mine both local and global features. Finally, ELM is chosen to carry out the prediction task to detect the potential lncRNA-disease associations. The proposed method achieved remarkable Area Under Receiver Operating Characteristic Curve of 0.9086 in Leave-one-out cross-validation and 0.8994 in fivefold cross-validation, respectively. In addition, 2 kinds of case studies based on lung cancer and endometrial cancer indicate the robustness and efficiency of LDACE even in a real environment. CONCLUSIONS: Substantial results demonstrated that the proposed model is expected to be an auxiliary tool to guide and assist biomedical research, and the close integration of deep learning and biology big data will provide life sciences with novel insights.


Asunto(s)
ARN Largo no Codificante , Biología Computacional/métodos , Aprendizaje Automático , Redes Neurales de la Computación , ARN Largo no Codificante/genética , Curva ROC
16.
Med Sci Monit ; 28: e933848, 2022 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-35194010

RESUMEN

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 (P<0.05). 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 (P<0.05). 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.


Asunto(s)
Reflujo Gastroesofágico/terapia , Terapia por Radiofrecuencia/métodos , Encuestas y Cuestionarios , Beijing/epidemiología , Endoscopía Gastrointestinal/métodos , Femenino , Estudios de Seguimiento , Reflujo Gastroesofágico/diagnóstico , Reflujo Gastroesofágico/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Retrospectivos
17.
Appl Environ Microbiol ; 88(3): e0208921, 2022 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-34818107

RESUMEN

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.


Asunto(s)
Halomonadaceae , Hemípteros , Complejo Vitamínico B , Animales , Autofagia , Halomonadaceae/genética , Hemípteros/microbiología , Simbiosis/genética , Complejo Vitamínico B/metabolismo
18.
PLoS Pathog ; 17(11): e1010120, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34843593

RESUMEN

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.


Asunto(s)
Evolución Molecular , Transferencia de Gen Horizontal , Halomonadaceae/fisiología , Hemípteros/microbiología , Lisina/metabolismo , Rickettsia/fisiología , Simbiosis , Animales , Hemípteros/genética , Hemípteros/crecimiento & desarrollo , Lisina/genética
19.
Sci Rep ; 11(1): 16910, 2021 08 19.
Artículo en Inglés | MEDLINE | ID: mdl-34413375

RESUMEN

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.


Asunto(s)
Evolución Molecular , Mapeo de Interacción de Proteínas , Bases de Datos de Proteínas , Humanos , Curva ROC , Reproducibilidad de los Resultados , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Máquina de Vectores de Soporte
20.
Org Lett ; 23(18): 7100-7105, 2021 09 17.
Artículo en Inglés | MEDLINE | ID: mdl-34436910

RESUMEN

An efficient method for the Lewis acid promotion of the synthesis 9-phosphoryl fluorenes has been reported. This method focuses on ketone phosphonylation to form a C-P bond and a C-C bond between diphenylmethanone and H-phosphinate esters, H-phosphites, and H-phosphine oxides via phospha-aldol elimination, in which a series of 9-phosphoryl fluorene derivatives were selectively obtained in moderate to excellent yields.

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