Deeply functional identification of TCS1 alleles provides efficient technical paths for low-caffeine breeding of tea plants

Caffeine is an important functional component in tea,which has the effect of excitement and nerve stimulation,but excessive intake can cause insomnia and dysphoria.Therefore,the production of tea with low-caffeine content can meet the consumption needs of certain people.Here,in addition to the previous alleles of the tea caffeine synthase(TCS1)gene,a new allele(TCS1h)from tea germplasms was identified.Results of in vitro activity analysis showed that TCS1h had both theobromine synthase(TS)and caffeine synthase(CS)activities.Site-directed mutagenesis experiments of TCS1a,TCS1c,and TCS1h demonstrated that apart from the 225th amino acid residue,the 269th amino acid also determined the CS activity.GUS histochemical analysis and dual-luciferase assay indicated the low promoter activity of TCS1e and TCS1f.In parallel,insertion and deletion mutations in large fragments of alleles and experiments of site-directed mutagenesis identified a key cis-acting element(G-box).Furthermore,it was found that the contents of purine alkaloids were related to the expression of corresponding functional genes and alleles,and the absence or presence and level of gene expression determined the content of purine alkaloids in tea plants to a certain extent.In summary,we concluded TCS1 alleles into three types with different functions and proposed a strategy to effectively enhance low-caffeine tea germplasms in breeding practices.This research provided an applicable technical avenue for accelerating the cultivation of specific low-caffeine tea plants.

Application effect of phloroglucinol injection in elderly patients with spastic abdominal pain in emergency department

BACKGROUND Although norepinephrine injection is commonly used in emergency situations,it is associated with risks for elderly patients with spasmodic liver pain.This study explores the safety and effectiveness of mebendazole injection,an alternative treatment option,for the emergency management of spasmodic abdominal pain,while minimizing adverse reactions,in elderly patients.AIM To explore the development of norepinephrine injection and the adverse reactions of this drug in emergency elderly patients with spasmodic liver pain.METHODS The control group consisted of 56 elderly patients visiting our hospital from January 2021 to December 2021.After hospital admission,the control group was intravenously administered tolopin.The experimental group consisted of 56 emergency patients with spasmodic abdominal pain who visited our hospital until June 2022.After hospital admission,the experimental group was intravenously administered toloxazole.The two groups were treated for 3 d.The disappearance of clinical symptoms was observed before and after the treatment,and the difference in adverse reactions between the two groups was compared.RESULTS The pain of the wife,fire,diarrhea,drowning,and surrounding time disappeared in the experimental group.No statistical difference was observed between the experimental and control groups in visual pain analog scale(VAS)scores before and after the treatment(P>0.05).The VAS scores of abdominal pain severity after 0.5 h,1.0 h,and after 6.0 h of treatment were significantly lower for the experimental group than for the control group.After the treatment,the therapeutic effect in the experimental group was higher and statistically significant than that in the control group(P<0.05).The probability of adverse reactions before the treatment was lower in the experimental group than in the control group.CONCLUSION During emergency,mebendazole injection exhibited a good therapeutic value when used for the clinical treatment of elderly patients with spasmodic stomach pain.It accelerated the disappearance of clinical symptoms such as stomach pain,reduced the stomach weight,and improved clinical activity.Reducing and promoting the frequency of high treatment safety with mebendazole injection is worthwhile.

The Philadelphia chromosome in leukemogenesis

The truncated chromosome 22 that results from the reciprocal translocation t(9;22)(q34;q11) is known as the Phila?delphia chromosome(Ph) and is a hallmark of chronic myeloid leukemia(CML).In leukemia cells,Ph not only impairs the physiological signaling pathways but also disrupts genomic stability.This aberrant fusion gene encodes the breakpoint cluster region?proto?oncogene tyrosine?protein kinase(BCR?ABL1) oncogenic protein with persistently enhanced tyrosine kinase activity.The kinase activity is responsible for maintaining proliferation,inhibiting differentia?tion,and conferring resistance to cell death.During the progression of CML from the chronic phase to the accelerated phase and then to the blast phase,the expression patterns of different BCR?ABL1 transcripts vary.Each BCR?ABL1 transcript is present in a distinct leukemia phenotype,which predicts both response to therapy and clinical outcome.Besides CML,the Ph is found in acute lymphoblastic leukemia,acute myeloid leukemia,and mixed?phenotype acute leukemia.Here,we provide an overview of the clinical presentation and cellular biology of different phenotypes of Ph?positive leukemia and highlight key findings regarding leukemogenesis.

Identification and distribution of a single nucleotide polymorphism responsible for the catechin content in tea plants

Catechins are the predominant products in tea plants and have essential functions for both plants and humans.Several genes encoding the enzymes regulating catechin biosynthesis have been identified,and the identification of single nucleotide polymorphisms(SNPs)resulting in nonsynonymous mutations within these genes can be used to establish a functional link to catechin content.Therefore,the transcriptomes of two parents and four filial offspring were sequenced using next-generation sequencing technology and aligned to the reference genome to enable SNP mining.Subsequently,176 tea plant accessions were genotyped based on candidate SNPs using kompetitive allelespecific polymerase chain reaction(KASP).The catechin contents of these samples were characterized by highperformance liquid chromatography(HPLC),and analysis of variance(ANOVA)was subsequently performed to determine the relationship between genotypes and catechin content.As a result of these efforts,a SNP within the chalcone synthase(CHS)gene was shown to be functionally associated with catechin content.Furthermore,the geographical and interspecific distribution of this SNP was investigated.Collectively,these results will contribute to the early evaluation of tea plants and serve as a rapid tool for accelerating targeted efforts in tea breeding.

Effect of transplantation of bone marrow stem cells on myocardial infarction size in a rabbit model

BACKGROUND:Intravenous transplantation has been regarded as a most safe method in stem cell therapies.There is evidence showing the homing of bone marrow stem cells(BMSCs) into the injured sites,and thus these cells can be used in the treatment of acute myocardial infarction(Ml).This study aimed to investigate the effect of intravenous and epicardial transplantion of BMSCs on myocardial infarction size in a rabbit model.METHODS:A total of 60 New Zealand rabbits were randomly divided into three groups:control group,epicardium group(group Ⅰ) and ear vein group(group Ⅱ).The BMSCs were collected from the tibial plateau in group Ⅰ and group Ⅱ,cultured and labeled.In the three groups,rabbits underwent thoracotomy and ligation of the middle left anterior descending artery.The elevation of ST segment>0.2 mV lasting for 30 minutes on the lead Ⅱ and Ⅲ of electrocardiogram suggested successful introduction of myocardial infarction.Two weeks after myocardial infarction,rabbits in group Ⅰ were treated with autogenous BMSCs at the infarct region and those in group Ⅱ received intravenous transplantation of BMSCs.In the control group,rabbits were treated with PBS following thoracotomy.Four weeks after myocardial infarction,the heart was collected from all rabbits and the infarct size was calculated.The heart was cut into sections followed by HE staining and calculation of infarct size with an image system.RESULTS:In groups Ⅰ and Ⅱ,the infarct size was significantly reduced after transplantation with BMSCs when compared with the control group(P<0.05).However,there was no significant difference in the infarct size between groups Ⅰ and Ⅱ(P>0.05).CONCLUSION:Transplantation of BMSCs has therapeutic effect on Ml.Moreover,epicardial and intravenous transplantation of BMSCs has comparable therapeutic efficacy on myocardial infarction.

Ultrafine Cu nanoclusters confined within covalent organic frameworks for efficient electroreduction of CO_(2) to CH_(4) by synergistic strategy

Electrocatalytic CO_(2) reduction(ECR)to high value-added chemicals by using renewable electricity presents a promising strategy to realize“carbon neutrality”.However,the ECR system is still limited by its low current density and poor CO_(2) utilization efficiency.Herein,by using the confinement effect of covalent organic frame-works(COFs)to confine the in-situ growth of metal nanoclusters(NCs),we develop a series of Cu NCs encap-sulated on COF catalysts(Cu-NC@COF)for ECR.Among them,Cu-NC@CuPc-COF as a gas diffusion electrode(GDE)achieves a maximum CO_(2)-to-CH_(4) Faradaic efficiency of 74±3%(at-1.0 V vs.Reversible Hydrogen Electrode(RHE))with a current density of 538±31 mA cm^(-2)(at-1.2 V vs.RHE)in a flow cell,making it one of the best among reported materials.More importantly,the current density is much higher than the relevant industrial current density(200 mA cm^(-2)),indicating the potential for industrial application.This work opens up new possibilities for the design of ECR catalysts that utilize synergistic strategy.

A novel micro-straw for cryopreservation of sma number of human spermatozoon

Cryopreservation of few spermatozoa is still a major challenge for male fertility preservation. This study reports use a new micro-straw （LSL straw） for freezing few spermatozoa for intracytoplasmic sperm injection （ICSI）. Semen samples from 22 fertile donors were collected, and each semen sample was diluted and mixed with cryoprotectant in a ratio of 1：1, and then frozen using three different straws such as LSL straw （50-100μl）, traditional 0.25 ml and 0.5 ml straws. For freezing, all straws were fumigated with liquid nitrogen, with temperature directly reducing to -130--140℃. Sperm concentration, progressive motility, morphology, acrosome integrity, and DNA fragmentation index were evaluated before and after freezing. After freezing-thawing, LSL straw group had significantly higher percentage of sperm motility than traditional 0.25 ml and 0.5 ml straw groups （38.5% vs 27.4% and 25.6%, P 〈 0.003）. Sperm motility and acrosomal integrity after freezing-thawing were significantly lower than that of before freezing. However, there was no significant difference in morphology, acrosome, and DNA integrity between the three types of straws （P 〉 0.05）. As LSL straws were thinner and hold very small volume, the freezing rate of LSL straw was obviously faster than 0.25 ml straw and 0.5 ml straws. In conclusion, LSL micro-straws may be useful to store few motile spermatozoa with good recovery of motility for patients undergoing ICSI treatment.

Novel double-layer Silastic testicular prosthesis with controlled release of testosterone in vitro, and its effects on castrated rats

Testicular prostheses have been used to deal with anorchia for nearly 80 years. Here, we evaluated a novel testicular prosthesis that can controllably release hormones to maintain physiological levels of testosterone in vivo for a long time. Silastic testicular prostheses with controlled release of testosterone （STPT） with different dosages of testosterone undecanoate （TU） were prepared and implanted into castrated Sprague-Dawley rats. TU oil was applied by oral administration to a separate group of castrated rats. Castrated untreated and sham-operated groups were used as controls. Serum samples from every group were collected to measure the levels of testosterone （T）, follicle-stimulating hormone and luteinizing hormone （LH）. Maximum intracavernous penile pressure （ICPmax） was recorded. The prostates and seminal vesicles were weighed and subjected to histology, and a terminal dexynucleotidyl transferase-mediated UTP nick end labeling （TUNEL） assay was used to evaluate apoptosis. Our results revealed that the weights of these tissues and the levels of T and LH showed significant statistical differences in the oral administration and TU replacement groups compared with the castrated group （P 〈 0.05）. Compared with the sham-operated group, the ICPmax, histology and TUNEL staining for apoptosis, showed no significant differences in the hormone replacement groups implanted with medium and high doses of STPT. Our results suggested that this new STPT could release TU stably through its double semi-permeable membranes with excellent biocompatibility. The study provides a new approach for testosterone replacement therapy.

A Review on the Development of Spaceborne Membrane Antennas

The membrane antenna technology is a very promising approach to obtain large aperture with light weight and low stowed volume.In the past decades,extensive studies have been carried out on active and passive membrane antennas.However,the practical spaceborne applications are rare due to many challenges,e.g.,the surface accuracy maintenance,the on-orbit reliability,and the environmental compatibility.This paper summarizes the history and state-of-art progresses on spaceborne membrane antennas.Curved surface reflectors,conformal active membrane antennas,planar array membrane antennas,and planar reflectarray membrane antennas have been introduced,respectively.Radiofrequency design,deploying mechanism,material,experiment,application,and analysis method have been presented.By concluding the advantages and challenges of the current membrane antennas,this paper is aimed at providing a perspective of the existing problems and future trend of spaceborne membrane antennas.