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1.
J Exp Bot ; 75(1): 258-273, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37721809

RESUMO

Intercropping improves resource utilization. Under wide-narrow-row maize (Zea mays) intercropping, maize plants are subjected to weak unilateral illumination and exhibit high photosynthetic performance. However, the mechanism regulating photosynthesis under unilateral weak light remains unknown. We investigated the relationship between photosynthesis and sugar metabolism in maize under unilateral weak light. Our results showed that the net photosynthetic rate (Pn) of unshaded leaves increased as the level of shade on the other side increased. On the contrary, the concentration of sucrose and starch and the number of starch granules in the unshaded leaves decreased with increased shading due to the transfer of abundant C into the grains. However, sink loss with ear removal reduced the Pn of unshaded leaves. Intense unilateral shade (40% to 20% normal light), but not mild unilateral shade (60% normal light), reduced grain yield (37.6% to 54.4%, respectively). We further found that in unshaded leaves, Agpsl, Bmy, and Mexl-like expression significantly influenced sucrose and starch metabolism, while Sweet13a and Sut1 expression was crucial for sugar export. In shaded leaves, expression of Sps1, Agpsl, and Sweet13c was crucial for sugar metabolism and export. This study confirmed that unshaded leaves transported photosynthates to the ear, leading to a decrease in sugar concentration. The improvement of photosynthetic performance was associated with altered sugar transport. We propose a narrow-row spacing of 40 cm, which provides appropriate unilateral shade and limits yield reduction.


Assuntos
Fotossíntese , Zea mays , Fotossíntese/fisiologia , Zea mays/fisiologia , Folhas de Planta/fisiologia , Amido , Sacarose
2.
J Sci Food Agric ; 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38980001

RESUMO

BACKGROUND: Relay intercropping of maize and soybean can improve land productivity. However, the mechanism behind N2O emissions in this practice remains unclear. A two-factor randomized block field trial was conducted to reveal the mechanism of N2O emissions in a full additive maize-soybean relay intercropping. Factor A was three cropping systems - that is, monoculture maize (Zea mays L.), monoculture soybean (Glycine max L. Merr.) and maize-soybean relay intercropping. Factor B was different N supply, containing no N, reduced N and conventional N. Differences in N2O emissions, soil properties, rhizosphere bacterial communities and yield advantage were evaluated. RESULTS: The land equivalent ratio was 1.55-2.44, and the cumulative N2O emission ( C E N 2 O $$ \mathrm{C}{\mathrm{E}}_{{\mathrm{N}}_2\mathrm{O}} $$ ) was notably lower by 60.2% in intercropping than in monoculture, respectively. Reduced N declined C E N 2 O $$ \mathrm{C}{\mathrm{E}}_{{\mathrm{N}}_2\mathrm{O}} $$ without penalty on the yield advantages. The relay intercropping shifted soil properties - for example, soil organic matter, total N, NH 4 + $$ {\mathrm{NH}}_4^{+} $$ and protease activity - and improved the soil microorganism community - for example, Proteobacteria and Acidobacteria. Intercropping reduced C E N 2 O $$ \mathrm{C}{\mathrm{E}}_{{\mathrm{N}}_2\mathrm{O}} $$ by directly suppressing nirS- and amoA-regulated N2O generation during soil N cycling, or nirS- and amoA-mediated soil properties shifted to reduce C E N 2 O $$ \mathrm{C}{\mathrm{E}}_{{\mathrm{N}}_2\mathrm{O}} $$ indirectly. Reduced N directly reduced C E N 2 O $$ \mathrm{C}{\mathrm{E}}_{{\mathrm{N}}_2\mathrm{O}} $$ by decreasing soil N content and reducing soil microorganism activities to alleviate N2O produced in soil N cycling. CONCLUSION: Conducting a full additive maize-soybean relay intercropping with reduced nitrogen supply provides a way to alleviate N2O emissions without the penalty on the yield advantage by changing rhizosphere bacterial communities and soil N cycling. © 2024 Society of Chemical Industry.

3.
Angew Chem Int Ed Engl ; 63(19): e202402363, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38497318

RESUMO

Crystalline frameworks represent a cutting-edge frontier in material science, and recently, there has been a surge of interest in energetic crystalline frameworks. However, the well-established porosity often leads to diminished output energy, necessitating a novel approach for performance enhancement. Thiol-yne coupling, a versatile metal-free click reaction, has been underutilized in crystalline frameworks. As a proof of concept, we herein demonstrate the potential of this approach by introducing the energy-rich, size-matched, and reductive 1,2-dicarbadodecaborane-1-thiol (CB-SH) into an acetylene-functionalized framework, Zn(AIm)2, via thiol-yne click reaction. This innovative decoration strategy resulted in a remarkable 46.6 % increase in energy density, a six-fold reduction in ignition delay time (4 ms) with red fuming nitric acid as the oxidizer, and impressive enhancement of stability. Density functional theory calculations were employed to elucidate the mechanism by which CB-SH promotes hypergolic ignition. The thiol-yne click modification strategy presented here permits engineering of crystalline frameworks for the design of advanced energetic materials.

4.
Mol Biol Evol ; 39(3)2022 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-35038730

RESUMO

The spotted hyena (Crocuta crocuta) is a large and unique terrestrial carnivore. It is a particularly fascinating species due to its distinct phenotypic traits, especially its complex social structure and scavenging lifestyle, with associated high dietary exposure to microbial pathogens. However, the underlying molecular mechanisms related to these phenotypes remain elusive. Here, we sequenced and assembled a high-quality long-read genome of the spotted hyena, with a contig N50 length of ∼13.75 Mb. Based on comparative genomics, immunoglobulin family members (e.g., IGKV4-1) showed significant adaptive duplications in the spotted hyena and striped hyena. Furthermore, immune-related genes (e.g., CD8A, LAG3, and TLR3) experienced species-specific positive selection in the spotted hyena lineage. These results suggest that immune tolerance between the spotted hyena and closely related striped hyena has undergone adaptive divergence to cope with prolonged dietary exposure to microbial pathogens from scavenging. Furthermore, we provided the potential genetic insights underlying social complexity, hinting at social behavior and cognition. Specifically, the RECNE-associated genes (e.g., UGP2 and ACTR2) in the spotted hyena genome are involved in regulation of social communication. Taken together, our genomic analyses provide molecular insights into the scavenging lifestyle and societal complexity of spotted hyenas.


Assuntos
Hyaenidae , Animais , Sequência de Bases , Genoma , Hyaenidae/genética , Comportamento Social
5.
BMC Plant Biol ; 23(1): 438, 2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37726682

RESUMO

Intercropping can obtain yield advantages, but the mechanism of yield advantages of maize-legume intercropping is still unclear. Then, we explored the effects of cropping systems and N input on yield advantages in a two-year experiment. Cropping systems included monoculture maize (Zea mays L.) (MM), monoculture soybean (Glycine max L. Merr.) (MS), monoculture peanut (Arachis hypogaea L.) (MP), maize-soybean substitutive relay intercropping (IMS), and maize-peanut substitutive strip intercropping (IMP). N input included without N (N0) and N addition (N1). Results showed that maize's leaf area index was 31.0% and 34.6% higher in IMS and IMP than in MM. The specific leaf weight and chlorophyll a (chl a) of maize were notably higher by 8.0% and 18.8% in IMS, 3.1%, and 18.6% in IMP compared with MM. Finally, N addition resulted in a higher thousand kernels weight of maize in IMS and IMP than that in MM. More dry matter accumulated and partitioned to the grain, maize's averaged partial land equivalent ratio and the net effect were 0.76 and 2.75 t ha-1 in IMS, 0.78 and 2.83 t ha-1 in IMP. The leaf area index and specific leaf weight of intercropped soybean were 16.8% and 26% higher than MS. Although soybean suffers from shade during coexistence, recovered growth strengthens leaf functional traits and increases dry matter accumulation. The averaged partial land equivalent ratio and the net effect of intercropped soybean were 0.76 and 0.47 t ha-1. The leaf area index and specific leaf weight of peanuts in IMP were 69.1% and 14.4% lower than in the MP. The chlorophyll a and chlorophyll b of peanut in MP were 17.0% and 24.4% higher than in IMP. A less dry matter was partitioned to the grain for intercropped peanut. The averaged pLER and NE of intercropped peanuts were 0.26 and -0.55 t ha-1. In conclusion, the strengthened leaf functional traits promote dry matter accumulation, maize-soybean relay intercropping obtained a win-win yield advantage, and maize-peanut strip intercropping achieved a trade-off yield advantage.


Assuntos
Fabaceae , Zea mays , Clorofila A , Verduras , Glycine max , Arachis , Folhas de Planta , Grão Comestível
6.
J Cardiovasc Pharmacol ; 81(4): 259-269, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36668724

RESUMO

ABSTRACT: Mitochondrial dysfunction plays a key role in the development of heart failure, but targeted therapeutic interventions remain elusive. Previous studies have shown coenzyme Q10 (CoQ10) insufficiency in patients with heart disease with undefined mechanism and modest effectiveness of CoQ10 supplement therapy. Using 2 transgenic mouse models of cardiomyopathy owing to cardiac overexpression of Mst1 (Mst1-TG) or ß 2 -adrenoceptor (ß 2 AR-TG), we studied changes in cardiac CoQ10 content and alterations in CoQ10 biosynthesis genes. We also studied in Mst1-TG mice effects of CoQ10, delivered by oral or injection regimens, on both cardiac CoQ10 content and cardiomyopathy phenotypes. High performance liquid chromatography and RNA sequencing revealed in both models significant reduction in cardiac content of CoQ10 and downregulation of most genes encoding CoQ10 biosynthesis enzymes. Mst1-TG mice with 70% reduction in cardiac CoQ10 were treated with CoQ10 either by oral gavage or i.p. injection for 4-8 weeks. Oral regimens failed in increasing cardiac CoQ10 content, whereas injection regimen effectively restored the cardiac CoQ10 level in a time-dependent manner. However, CoQ10 restoration in Mst1-TG mice did not correct mitochondrial dysfunction measured by energy metabolism, downregulated expression of marker proteins, and oxidative stress nor to preserve cardiac contractile function. In conclusion, mouse models of cardiomyopathy exhibited myocardial CoQ10 deficiency likely due to suppressed endogenous synthesis of CoQ10. In contrast to ineffectiveness of oral administration, CoQ10 administration by injection regimen in cardiomyopathy mice restored cardiac CoQ10 content, which, however, failed in achieving detectable efficacy at molecular and global functional levels.


Assuntos
Cardiomiopatias , Ubiquinona , Camundongos , Animais , Ubiquinona/metabolismo , Ubiquinona/uso terapêutico , Cardiomiopatias/tratamento farmacológico , Cardiomiopatias/genética , Coração , Camundongos Transgênicos
7.
Phytother Res ; 35(11): 6401-6416, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34585457

RESUMO

Although renal fibrosis is a common complication of chronic kidney disease (CKD), effective options for its treatment are currently limited. In this study, we evaluated the renal protective effect and possible mechanism of eleutheroside B. In order to solve the allergic reactions, side effects, and low oral bioavailability of eleutheroside B, we successfully prepared PLGA (poly [lactic-co-glycolic acid])-eleutheroside B nanoparticles (NPs) with the diameter of about 128 nm. In vitro and in vivo results showed that eleutheroside B could inhibit expression levels of α-smooth muscle actin (α-SMA) and collagen I. Molecular docking results showed that eleutheroside B bound to Smad3 and significantly decreased the expression of phospho-Smad3 (p-Smad3). Silencing Smad3 reversed the fibrotic protective effect of eleutheroside B in HK2 cells. Furthermore, small animal imaging showed that NPs can selectively accumulate in the UUO kidneys of mice, and retention time reached as long as 7 days. In conclusion, our results suggested that eleutheroside B is a potential drug to protect renal fibrosis and PLGA-eleutheroside B NPs could facilitate specific targeted therapy for renal fibrosis.


Assuntos
Fibrose , Nefropatias , Nanopartículas , Animais , Glucosídeos , Glicolatos , Nefropatias/tratamento farmacológico , Camundongos , Simulação de Acoplamento Molecular , Fenilpropionatos , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Proteína Smad3
8.
HPB (Oxford) ; 23(8): 1217-1229, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33413992

RESUMO

BACKGROUND: A method for predicting prognosis of patients who undergo partial hepatectomy for huge hepatocellular carcinoma (HHCC, diameter ≥10 cm) is currently lacking. This study aimed to establish two online nomograms to predict the overall survival (OS) and disease-free survival (DFS) for patients undergoing resection for HHCC. METHODS: The clinicopathologic characteristics and follow-up information of patients who underwent partial hepatectomy for HHCC at two medical centers were reviewed. Using a training cohort, a Cox model was used to identify the predictors of survival. Two dynamic nomograms for OS and DFS were developed and validated based on the data. RESULTS: Eight and nine independent factors derived from the multivariate analysis of the training cohort were screened and incorporated into the nomograms for OS and DFS, respectively. In the training cohort, the nomogram achieved concordance indices (C-indices) of 0.745 and 0.738 in predicting the OS and DFS, respectively. These results were supported by external validation (C-indices: 0.822 for OS and 0.827 for DFS). Further, the calibration curves of the endpoints showed a favorable agreement between the nomograms' assessments and actual observations. CONCLUSIONS: The two web-based nomograms demonstrated optimal predictive performance for patients undergoing partial hepatectomy for HHCC. This provides a practical method for a personalized prognosis based on an individual's underlying risk factors.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Carcinoma Hepatocelular/cirurgia , Hepatectomia/efeitos adversos , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/cirurgia , Nomogramas , Prognóstico , Estudos Retrospectivos
9.
J Cell Mol Med ; 24(5): 2901-2916, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32000296

RESUMO

Glioblastoma (GBM) continues to show a poor prognosis despite advances in diagnostic and therapeutic approaches. The discovery of reliable prognostic indicators may significantly improve treatment outcome of GBM. In this study, we aimed to explore the function of verbascoside (VB) in GBM and its effects on GBM cell biological processes via let-7g-5p and HMGA2. Differentially expressed GBM-related microRNAs (miRNAs) were initially screened. Different concentrations of VB were applied to U87 and U251 GBM cells, and 50 µmol/L of VB was selected for subsequent experiments. Cells were transfected with let-7g-5p inhibitor or mimic, and overexpression of HMGA2 or siRNA against HMGA2 was induced, followed by treatment with VB. The regulatory relationships between VB, let-7g-5p, HMGA2 and Wnt/ß-catenin signalling pathway were determined. The results showed that HMGA2 was a direct target gene of let-7g-5p. VB treatment or let-7g-5p overexpression inhibited HMGA2 expression and the activation of Wnt/ß-catenin signalling pathway, which further inhibited cell viability, invasion, migration, tumour growth and promoted GBM cell apoptosis and autophagy. On the contrary, HMGA2 overexpression promoted cell viability, invasion, migration, tumour growth while inhibiting GBM cell apoptosis and autophagy. We demonstrated that VB inhibits cell viability and promotes cell autophagy in GBM cells by up-regulating let-7g-5p and down-regulating HMGA2 via Wnt/ß-catenin signalling blockade.


Assuntos
Progressão da Doença , Regulação para Baixo/genética , Glioblastoma/genética , Glioblastoma/patologia , Glucosídeos/farmacologia , Proteína HMGA2/genética , MicroRNAs/metabolismo , Fenóis/farmacologia , Via de Sinalização Wnt/genética , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Autofagia/efeitos dos fármacos , Autofagia/genética , Sequência de Bases , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Movimento Celular/genética , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Regulação para Baixo/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Proteína HMGA2/metabolismo , Humanos , Camundongos Nus , MicroRNAs/genética , Invasividade Neoplásica , Proteína Quinase C/metabolismo , Via de Sinalização Wnt/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
10.
J Gene Med ; 22(3): e3146, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31742804

RESUMO

BACKGROUND: Hypertrophic cardiomyopathy (HCM) is the most common inheritable cardiac disease and is characterised by unexplained ventricular myocardial hypertrophy. HCM is highly heterogeneous and is primarily caused by the mutation of genes encoding sarcomere proteins. As a result of its genetic basis, we investigated the underlying cause of HCM in a Chinese family by whole-exome sequencing. METHODS: Whole-exome sequencing was performed for seven clinically diagnosed HCM family members and the resulting single nucleotide variants associated with cardiac hypertrophy or heart development were analysed by a polymerase chain reaction and Sanger sequencing. RESULTS: A non-frameshift deletion mutation (p.S527del) of Formin Homology 2 Domain Containing 3 (FHOD3) was detected in all of the affected family members and was absent in all unaffected members, with the exception of one young member. Moreover, three single nucleotide variants associated with heart development and morphogenesis were identified in the proband but were absent in the other affected subjects. CONCLUSIONS: This is the first HCM family case of FHOD3 (p.S527del) variation in Asia. Additionally, RNF207 (p.Q268P), CCM2 (p. E233K) and SGCZ (p.Q134X) may be related to the clinical heterogeneity of the family. The present study could enable the provision of genetic counseling for this family and provide a basis for future genetic and functional studies.


Assuntos
Cardiomiopatia Hipertrófica/genética , Exoma , Forminas/genética , Povo Asiático , Cardiomiopatia Hipertrófica/diagnóstico , Feminino , Predisposição Genética para Doença , Variação Genética , Humanos , Masculino , Mutação , Linhagem , Reação em Cadeia da Polimerase , Polimorfismo de Nucleotídeo Único , Deleção de Sequência , Sequenciamento do Exoma
11.
Physiol Plant ; 170(3): 345-356, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32588443

RESUMO

Soybean is an important oilseed crop grown globally. However, two examples of environmental stresses that drastically regulate soybean growth are low light and high-temperature. Emerging evidence suggests a possible interconnection between these two environmental stimuli. Low light and high-temperature as individual factors have been reported to regulate plant hypocotyl elongation. However, their interactive signal effect on soybean growth and development remains largely unclear. Here, we report that gibberellins (GAs) and auxin are required for soybean hypocotyl elongation under low light and high-temperature interaction. Our analysis indicated that low light and high-temperature interaction enhanced the regulation of soybean hypocotyl elongation and that the endogenous GA3 , GA7 , indole-3-acetic acid (IAA), and indole-3-pyruvate (IPA) contents significantly increased. Again, analysis of the effect of exogenous phytohormones and biosynthesis inhibitors treatments showed that exogenous GA, IAA, and paclobutrazol (PAC), 2, 3, 5,-triiodobenzoic acid (TIBA) treatments significantly regulated soybean seedlings growth under low light and high-temperature interaction. Further qRT-PCR analysis showed that the expression level of GA biosynthesis pathway genes (GmGA3ox1, GmGA3ox2 and GmGA3) and auxin biosynthesis pathway genes (GmYUCCA3, GmYUCCA5 and GmYUCCA7) significantly increased under (i) low light and high-temperature interaction and (ii) exogenous GA and IAA treatments. Altogether, these observations support the hypothesis that gibberellins and auxin regulate soybean hypocotyl elongation under low light and high-temperature stress interaction.


Assuntos
Arabidopsis , Giberelinas , Regulação da Expressão Gênica de Plantas , Giberelinas/farmacologia , Hipocótilo , Ácidos Indolacéticos , Luz , Glycine max/genética , Temperatura
12.
Mol Genet Genomics ; 293(1): 217-223, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29018978

RESUMO

Conotruncal heart defects (CTDs) are a group of cardiac malformations that involve outflow tract anomalies and the arterial pole of the heart. Recent reports have identified mutations in a number of genes associated with CTDs in human and animal models. ZFPM2 plays a role in cardiac development by acting as a transcriptional cofactor that interacts with GATA4. Because ZFPM2 was found to be important for cardiac development in a knockout mouse model, we screened for ZFPM2 mutations in 528 CTD patients. We identified six rare and nonsynonymous ZFPM2 variants, and this was the first time that five of these variants (R698Q, R736L, E1005K, T32A, and I488V) were reported in East Asians. Western blots showed that there was no significant difference in the protein expression of wild-type ZFPM2, ZFPM2R698Q, or ZFPM2R736L. A dual luciferase reporter assay demonstrated that both ZFPM2 mutants R698Q and R736L reduced GATA4-mediated transcription. However, when ZFPM2R698Q was co-transfected with GATA4, BNP promoter activity increased significantly, whereas co-transfection with ZFPM2R736L and GATA4 did not significantly increase BNP promoter activity. This suggests that the R698Q mutation may affect the ability of ZFPM2 to bind GATA4.


Assuntos
Proteínas de Ligação a DNA/genética , Fator de Transcrição GATA4/genética , Predisposição Genética para Doença , Cardiopatias Congênitas/genética , Fatores de Transcrição/genética , Animais , Análise Mutacional de DNA , Proteínas de Ligação a DNA/metabolismo , Feminino , Fator de Transcrição GATA4/metabolismo , Cardiopatias Congênitas/metabolismo , Cardiopatias Congênitas/patologia , Humanos , Masculino , Camundongos , Mutação de Sentido Incorreto , Ligação Proteica , Fatores de Transcrição/metabolismo
13.
Twin Res Hum Genet ; 20(6): 521-532, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29192580

RESUMO

Congenital heart disease (CHD) is one of the most common birth defects. More than 200 susceptibility loci have been identified for CHDs, yet a large part of the genetic risk factors remain unexplained. Monozygotic (MZ) twins are thought to be completely genetically identical; however, discordant phenotypes have been found in MZ twins. Recent studies have demonstrated genetic differences between MZ twins. We aimed to test whether copy number variants (CNVs) and/or genetic mutation differences play a role in the etiology of CHDs by using single nucleotide polymorphism (SNP) genotyping arrays and whole exome sequencing of twin pairs discordant for CHDs. Our goal was to identify mutations present only in the affected twins, which could identify novel candidates for CHD susceptibility loci. We present a comprehensive analysis for the CNVs and genetic mutation results of the selected individuals but detected no consistent differences within the twin pairs. Our study confirms that chromosomal structure or genetic mutation differences do not seem to play a role in the MZ twins discordant for CHD.


Assuntos
Variações do Número de Cópias de DNA/genética , Doenças em Gêmeos/genética , Cardiopatias Congênitas/genética , Gêmeos Monozigóticos/genética , Adulto , China/epidemiologia , Doenças em Gêmeos/patologia , Exoma/genética , Feminino , Genótipo , Cardiopatias Congênitas/patologia , Humanos , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Mutação , Sequenciamento do Exoma
14.
J Electron Imaging ; 25(6)2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28458481

RESUMO

Visual prostheses require an effective representation method due to the limited display condition which has only 2 or 3 levels of grayscale in low resolution. Edges derived from abrupt luminance changes in images carry essential information for object recognition. Typical binary (black and white) edge images have been used to represent features to convey essential information. However, in scenes with a complex cluttered background, the recognition rate of the binary edge images by human observers is limited and additional information is required. The polarity of edges and cusps (black or white features on a gray background) carries important additional information; the polarity may provide shape from shading information missing in the binary edge image. This depth information may be restored by using bipolar edges. We compared object recognition rates from 16 binary edge images and bipolar edge images by 26 subjects to determine the possible impact of bipolar filtering in visual prostheses with 3 or more levels of grayscale. Recognition rates were higher with bipolar edge images and the improvement was significant in scenes with complex backgrounds. The results also suggest that erroneous shape from shading interpretation of bipolar edges resulting from pigment rather than boundaries of shape may confound the recognition.

15.
Cell Physiol Biochem ; 37(3): 1066-74, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26401820

RESUMO

BACKGROUND/AIMS: Congenital heart defects (CHD) can occur with upper limbs deformities. Holt-Oram syndrome is the main type of heart-hand syndromes, characterized by upper limb radial ray malformations, CHD and/or conduction abnormalities. Mutations of the TBX5 gene, most of which are found within the T-box domain, are one cause of the disease. We aimed to find the cause of the disease in a family with two children exhibiting symptoms of Holt-Oram syndrome while the parents tend to be normal. METHODS: Chromosomal microarray analysis and exome sequencing were applied in the proband segments bearing the specific mutation and single nucleotide variants (SNVs) suspected of being involved in the disease were analyzed by polymerase chain reaction and direct sequencing. RESULTS: A splice acceptor site mutation c.148-1G>C of TBX5 was detected in both the father and the proband. The mutation may result in an aberrant transcript which will most probably undergo nonsense-mediated decay (NMD) system resulting in haploinsufficiency of TBX5 protein. In the meantime, 3 candidated SNVs were detected. CONCLUSIONS: c.148-1G>C of TBX5 should be the pathogenic cause of the disease in this family. Works have been done to find a possible explanation of the unusual genotype-phenotype correlations in this family and further studies are still needed.


Assuntos
Anormalidades Múltiplas/patologia , Estudos de Associação Genética/métodos , Cardiopatias Congênitas/patologia , Comunicação Interatrial/patologia , Deformidades Congênitas das Extremidades Inferiores/patologia , Mutação Puntual , Análise de Sequência de DNA/métodos , Proteínas com Domínio T/genética , Deformidades Congênitas das Extremidades Superiores/patologia , Anormalidades Múltiplas/genética , Adulto , Citosina/metabolismo , Exoma , Guanina/metabolismo , Cardiopatias Congênitas/genética , Comunicação Interatrial/genética , Humanos , Lactente , Deformidades Congênitas das Extremidades Inferiores/genética , Masculino , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Linhagem , Sítios de Splice de RNA , Deformidades Congênitas das Extremidades Superiores/genética
16.
Cell Physiol Biochem ; 35(1): 270-80, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25591769

RESUMO

BACKGROUND: Cornelia de Lange Syndrome (CdLS) is a rare but severe clinically heterogeneous developmental disorder characterized by facial dysmorphia, growth and cognitive retardation, and abnormalities of limb development. OBJECTIVES: To determine the pathogenesis of a patient with CdLS. METHODS: We studied a patient with CdLS by whole exome sequencing, karyotyping and Agilent CGH Array. The results were confirmed by quantitative real-time PCR analysis of the patient and her parents. Further comparison of our patient and cases with partially overlapping deletions retrieved from the literature and databases was undertaken. RESULTS: Whole exome sequencing had excluded the mutation of cohesion genes such as NIPBL,SMC1A and SMC3. The result of karyotyping showed a deletion of chromosome 9q31.1-q32 and the result of Agilent CGH Array further displayed a 12.01-Mb region of deletion at chromosome bands 9q31.1-q32. Reported cases with the deletion of 9q31.1-q32 share similar features with our CdLS patient. One of the genes in the deleted region, SMC2, belongs to the Structural Maintenance of Chromosomes (SMC) family and regulates gene expression and DNA repair. CONCLUSIONS: Patients carrying the deletion of 9q31.1-q32 showed similar phenotypes with CdLS.


Assuntos
Cromossomos Humanos Par 9 , Síndrome de Cornélia de Lange/genética , Hibridização Genômica Comparativa , Síndrome de Cornélia de Lange/patologia , Ecocardiografia , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Lactente , Cariotipagem , Fenótipo , Análise de Sequência de DNA
17.
Biotechnol Appl Biochem ; 62(6): 765-71, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25524457

RESUMO

Nogalamycin is an anthracycline antitumor antibiotic, consisting of the aromatic aglycone attached with a nogalose and a nogalamine. At present, the biosynthesis pathway of nogalamycin, especially the glycosylation mechanism of the two deoxysugar moieties, had still not been extensively investigated in vivo. In this study, we inactivated the three glycotransferase genes in the nogalamycin-produced strain, and investigated the function of these genes by analyzing the metabolites profiles in the fermentation broth. The in-frame deletion of snogD and disruption of snogE abolished the production of nogalamycin completely, indicating that the gene products of snogD and snogE are essential to the biosynthesis of nogalamycin. On the other hand, in-frame deletion of snogZ does not abolish the production of nogalamycin, but production yield was reduced to 28% of the wild type, implying that snogZ gene may involved in the activation of other glycotransferases in nogalamycin biosynthesis. This study laid the foundation of modification of nogalamycin biosynthesis/production by genetic engineering methods.


Assuntos
Inativação Gênica , Engenharia Genética/métodos , Glicosiltransferases/deficiência , Glicosiltransferases/genética , Nogalamicina/biossíntese , Escherichia coli/genética , Escherichia coli/metabolismo , Glicosiltransferases/metabolismo , Alinhamento de Sequência , Streptomyces/genética , Streptomyces/metabolismo
18.
PLoS One ; 19(7): e0290805, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38985788

RESUMO

OBJECTIVE: Chronic inflammation and dyslipidemia are key risk factors for atherosclerotic cardiovascular diseases. We retrospectively explored the association between the neutrophil to lymphocyte ratio (NLR), the ratio of low-density lipoprotein cholesterol (LDL-C) to high-density lipoprotein cholesterol (HDL-C), and the neutrophil to HDL-C ratio (NHR), and the severity of coronary lesions in patients with acute coronary syndrome (ACS). METHOD: In June 2023, we selected 1210 patients who were diagnosed with ACS based on chest pain from January 2017 to December 2022. Of these, 1100 patients with abnormal coronary angiography were categorized into the experimental group, and 110 patients with normal coronary angiography were classified as the control group. We collected routine blood tests, lipid profiles, and coronary angiography results at admission (before coronary angiography). Patients were then stratified into a control group (Gensini score = 0) and an experimental group (Gensini score = 0) based on the Gensini score. The experimental group was further divided into a low score group (Gensini score < 69) and a high score group (Gensini score ≥ 69). RESULT: 1. Statistically significant differences were observed between the control and experimental groups in terms of gender, age, body mass index (BMI), hypertension, diabetes, smoking history, and counts of neutrophils (NEU), lymphocytes (LYM), monocytes (MON), eosinophils (EOS), red cell distribution width (RDW), total cholesterol (TC), HDL-C, LDL-C, NLR, LDL-C/HDL-C, and NHR (P<0.05). Furthermore, differences in BMI, hypertension, diabetes, smoking history, NEU, LYM, MON, TC, triglyceride (TG), HDL-C, LDL-C, NLR, LDL-C/HDL-C, and NHR were significant between the low and high score groups (P<0.05). 2. NEU, LYM, MON, TC, HDL-C, LDL-C, NLR, LDL-C/HDL-C, and NHR showed significant correlations with the Gensini score (r>0.2, P<0.05), with NLR and LDL-C/HDL-C showing the strongest correlations (r = 0.822, P = 0.000). 3. The Receiver Operating Characteristic (ROC) curve indicated that the combination of NLR and LDL-C/HDL-C had superior sensitivity and specificity in predicting the severity of coronary lesions, with a significant difference (P<0.05). The sensitivity was 87.1%, the specificity was 90.9%, and the cut-off point was 2.04. 4. A predictive model was developed based on the ratio of NLR and LDL-C/HDL-C to the Gensini score. The final model score was calculated as 6.803 + 7.029NLR + 13.079LDL-C/HDL-C (R2 = 0.708). CONCLUSION: Compared to NLR, LDL-C/HDL-C, and NHR, the combined NLR and LDL-C/HDL-C ratio is a more accurate marker for assessing the severity of coronary artery disease in ACS patients. Its convenience and effectiveness make it a promising tool for early assessment, timely risk stratification, and appropriate clinical intervention, ultimately improving clinical outcomes for ACS patients.


Assuntos
HDL-Colesterol , LDL-Colesterol , Doença da Artéria Coronariana , Linfócitos , Neutrófilos , Humanos , Feminino , Masculino , HDL-Colesterol/sangue , Pessoa de Meia-Idade , Doença da Artéria Coronariana/sangue , LDL-Colesterol/sangue , Idoso , Estudos Retrospectivos , Angiografia Coronária , Síndrome Coronariana Aguda/sangue , Fatores de Risco
19.
Health Inf Sci Syst ; 12(1): 5, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38093715

RESUMO

Liver cancer is the leading cause of mortality in the world. Over the years, researchers have spent much effort in developing computer-aided techniques to improve clinicians' diagnosis efficiency and precision, aiming at helping patients with liver cancer to take treatment early. Recently, attention mechanisms can enhance the representational power of convolutional neural networks (CNNs), which have been widely used in medical image analysis. In this paper, we propose a novel architectural unit, local cross-channel recalibration (LCR) module, dynamically adjusting the relative importance of intermediate feature maps by considering the roles of different global context features and building the local dependencies between channels. LCR first extracts different global context features and integrates them by global context integration operator, then estimates per channel attention weight with a local cross-channel interaction manner. We combine the LCR module with the residual block to form a Residual-LCR module and construct a deep neural network termed local cross-channel recalibration network (LCRNet) based on a stack of Residual-LCR modules to recognize live cancer atomically based on CT images. Furthermore, This paper collects a clinical CT image dataset of liver cancer, AMU-CT, to verify the effectiveness of LCRNet, which will be publicly available. The experiments on the AMU-CT dataset and public SD-OCT dataset demonstrate our LCRNet significantly outperforms state-of-the-art attention-based CNNs. Specifically, our LCRNet improves accuracy by over 11% than ECANet on the AMU-CT dataset. Supplementary Information: The online version contains supplementary material available at 10.1007/s13755-023-00263-6.

20.
Ticks Tick Borne Dis ; 15(2): 102293, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38086248

RESUMO

Ticks are primary vectors for many tick-borne pathogens (TBPs) and pose a serious threat to veterinary and public health. Information on the presence of TBPs in Chinese Milu deer (Elaphurus davidianus) is limited. In this study, a total of 102 Chinese Milu deer blood samples were examined for Anaplasma spp., Theileria spp., Babesia spp., Rickettsia spp., and Borrelia spp., and three TBPs were identified: Anaplasma phagocytophilum (48; 47.1 %), Candidatus Anaplasma boleense (47; 46.1%), and Theileria capreoli (8; 7.8 %). Genetic and phylogenetic analysis of the 16S rRNA and 18S rRNA confirmed their identity with corresponding TBPs. To our knowledge, this is the first report on Candidatus A. boleense and T. capreoli detection in Chinese Milu deer. A high prevalence of A. phagocytophilum with veterinary and medical significance was identified in endangered Chinese Milu deer, which could act as potential zoonotic reservoirs. The identification of the TBPs in Chinese Milu deer provides useful information for the prevention and control of tick-borne diseases.


Assuntos
Cervos , Rickettsia , Theileria , Doenças Transmitidas por Carrapatos , Carrapatos , Animais , Carrapatos/microbiologia , Cervos/microbiologia , Filogenia , RNA Ribossômico 16S/genética , Rickettsia/genética , Anaplasma/genética , Doenças Transmitidas por Carrapatos/epidemiologia , Doenças Transmitidas por Carrapatos/veterinária , Doenças Transmitidas por Carrapatos/microbiologia , Theileria/genética , China/epidemiologia
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