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1.
Nature ; 629(8014): 1075-1081, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38811711

RESUMO

Climate warming induces shifts from snow to rain in cold regions1, altering snowpack dynamics with consequent impacts on streamflow that raise challenges to many aspects of ecosystem services2-4. A straightforward conceptual model states that as the fraction of precipitation falling as snow (snowfall fraction) declines, less solid water is stored over the winter and both snowmelt and streamflow shift earlier in season. Yet the responses of streamflow patterns to shifts in snowfall fraction remain uncertain5-9. Here we show that as snowfall fraction declines, the timing of the centre of streamflow mass may be advanced or delayed. Our results, based on analysis of 1950-2020 streamflow measurements across 3,049 snow-affected catchments over the Northern Hemisphere, show that mean snowfall fraction modulates the seasonal response to reductions in snowfall fraction. Specifically, temporal changes in streamflow timing with declining snowfall fraction reveal a gradient from earlier streamflow in snow-rich catchments to delayed streamflow in less snowy catchments. Furthermore, interannual variability of streamflow timing and seasonal variation increase as snowfall fraction decreases across both space and time. Our findings revise the 'less snow equals earlier streamflow' heuristic and instead point towards a complex evolution of seasonal streamflow regimes in a snow-dwindling world.


Assuntos
Aquecimento Global , Chuva , Estações do Ano , Neve , Ecossistema , Rios , Fatores de Tempo , Movimentos da Água , Aquecimento Global/estatística & dados numéricos , Análise Espaço-Temporal
2.
Anal Chem ; 96(8): 3335-3344, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38363654

RESUMO

Metabolomics has emerged as a powerful tool in biomedical research to understand the pathophysiological processes and metabolic biomarkers of diseases. Nevertheless, it is a significant challenge in metabolomics to identify the reliable core metabolites that are closely associated with the occurrence or progression of diseases. Here, we proposed a new research framework by integrating detection-based metabolomics with computational network biology for function-guided and network-based identification of core metabolites, namely, FNICM. The proposed FNICM methodology is successfully utilized to uncover ulcerative colitis (UC)-related core metabolites based on the significantly perturbed metabolic subnetwork. First, seed metabolites were screened out using prior biological knowledge and targeted metabolomics. Second, by leveraging network topology, the perturbations of the detected seed metabolites were propagated to other undetected ones. Ultimately, 35 core metabolites were identified by controllability analysis and were further hierarchized into six levels based on confidence level and their potential significance. The specificity and generalizability of the discovered core metabolites, used as UC's diagnostic markers, were further validated using published data sets of UC patients. More importantly, we demonstrated the broad applicability and practicality of the FNICM framework in different contexts by applying it to multiple clinical data sets, including inflammatory bowel disease, colorectal cancer, and acute coronary syndrome. In addition, FNICM was also demonstrated as a practicality methodology to identify core metabolites correlated with the therapeutic effects of Clematis saponins. Overall, the FNICM methodology is a new framework for identifying reliable core metabolites for disease diagnosis and drug treatment from a systemic and a holistic perspective.


Assuntos
Colite Ulcerativa , Metabolômica , Humanos , Metabolômica/métodos , Biologia Computacional/métodos , Colite Ulcerativa/diagnóstico
3.
Ann Hematol ; 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38907072

RESUMO

Myelofibrosis is a rare and often fatal hematological neoplasm, and the treatment of myelofibrosis-associated anemia remains suboptimal, with no improved therapies. Luspatercept was shown to display some efficacy in a phase 2 clinical trial for Myelofibrosis with anemia, yet relevant research are limited. Threrfore, data from patients diagnosed with refractory anemic primary or post-essential thrombocythemia/polycythemia vera myelofibrosis, who were treated with luspatercept for at least 9 weeks, were retrospectively collected. Eighteen patients with myelofibrosis treated with luspatercept were enrolled. Median age was 68 years (range, 44-80 years), and 27.8% were males. Ten (55.6%) were transfusion-dependent. Ten (55.6%) were Dynamic International Prognostic Scoring System intermediate-1, and eight (44.4%) were intermediate-2. The median follow-up was 7 (4-16) months. Erythroid response occurred in eight patients (44.4%) at week 12, four patients (30.8%) at week 24, and nine (50%) at the end of follow-up. Patients who were transfusion-dependent and not transfusion-dependent had similar HI-E responses, at different time points (P > 0.05). Patients had a significantly higher hemoglobin level at 12 weeks, 24 weeks, and at the end of follow-up, than at baseline (P = 0.001, P = 0.021, and P = 0.005, respectively). Treatment-related adverse events occurred in five (16.7%) patients, with no serious adverse events. Two (11.1%) patients relapsed at weeks 15 and 31. One patient progressed to acute myeloid leukemia. No patients had died by the end of follow-up. Luspatercept induced a good response in patients with anemic myelofibrosis, with a low relapse rate and good tolerance.

4.
Virol J ; 21(1): 114, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38778344

RESUMO

BACKGROUND: EV71 is one of the important pathogens of Hand-foot-and-mouth disease (HFMD), which causes serious neurological symptoms. Several studies have speculated that there will be interaction between 5'UTR and 3D protein. However, whether 5'UTR interacts with the 3D protein in regulating virus replication has not been clarified. METHODS: Four 5'UTR mutation sites (nt88C/T, nt90-102-3C, nt157G/A and nt574T/A) and two 3D protein mutation sites (S37N and R142K) were mutated or co-mutated using virulent strains as templates. The replication of these mutant viruses and their effect on autophagy were determined. RESULTS: 5'UTR single-point mutant strains, except for EGFP-EV71(nt90-102-3C), triggered replication attenuation. The replication ability of them was weaker than that of the parent strain the virulent strain SDLY107 which is the fatal strain that can cause severe neurological complications. While the replication level of the co-mutant strains showed different characteristics. 5 co-mutant strains with interaction were screened: EGFP-EV71(S37N-nt88C/T), EGFP-EV71(S37N-nt574T/A), EGFP-EV71(R142K-nt574T/A), EGFP-EV71(R142K-nt88C/T), and EGFP-EV71(R142K-nt157G/A). The results showed that the high replicative strains significantly promoted the accumulation of autophagosomes in host cells and hindered the degradation of autolysosomes. The low replicative strains had a low ability to regulate the autophagy of host cells. In addition, the high replicative strains also significantly inhibited the phosphorylation of AKT and mTOR. CONCLUSIONS: EV71 5'UTR interacted with the 3D protein during virus replication. The co-mutation of S37N and nt88C/T, S37N and nt574T/ A, R142K and nt574T/A induced incomplete autophagy of host cells and promoted virus replication by inhibiting the autophagy pathway AKT-mTOR. The co-mutation of R142K and nt88C/T, and R142K and nt157G/A significantly reduced the inhibitory effect of EV71 on the AKT-mTOR pathway and reduced the replication ability of the virus.


Assuntos
Regiões 5' não Traduzidas , Enterovirus Humano A , Proteínas Proto-Oncogênicas c-akt , Serina-Treonina Quinases TOR , Replicação Viral , Enterovirus Humano A/genética , Enterovirus Humano A/fisiologia , Enterovirus Humano A/patogenicidade , Regiões 5' não Traduzidas/genética , Humanos , Serina-Treonina Quinases TOR/metabolismo , Serina-Treonina Quinases TOR/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Autofagia , Animais , Proteínas não Estruturais Virais/genética , Proteínas não Estruturais Virais/metabolismo , Transdução de Sinais , Chlorocebus aethiops , Mutação , Linhagem Celular , Células Vero
5.
Int J Behav Nutr Phys Act ; 21(1): 17, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38355565

RESUMO

BACKGROUND: How physical activity (PA) and different sleep traits and overall sleep pattern interact in the development of Parkinson's disease (PD) remain unknown. OBJECTIVE: To prospectively investigate the joint associations of PA and sleep pattern with risk of PD. METHODS: Included were 339,666 PD-free participants from the UK Biobank. Baseline PA levels were grouped into low (< 600 MET-mins/week), medium (600 to < 3000 MET-mins/week) and high (≥ 3000 MET-mins/week) according to the instructions of the UK Biobank. Healthy sleep traits (chronotype, sleep duration, insomnia, snoring, and daytime sleepiness) were scored from 0 to 5 and were categorized into "ideal sleep pattern" (≥ 3 sleep scores) and "poor sleep pattern" (0-2 sleep scores). Hazard ratios (HRs) and 95% confidence intervals (CIs) of PD were estimated by Cox proportional hazards models. RESULTS: During a median of 11.8 years of follow-up, 1,966 PD events were identified. The PD risk was lower in participants with high PA (HR = 0.73; 95% CI: 0.64, 0.84), compared to those with low PA; and participants with ideal sleep pattern also had a lower risk of PD (HR = 0.78; 95% CI: 0.69, 0.87), compared to those with poor sleep pattern. When jointly investigating the combined effect, participants with both high PA and ideal sleep pattern had the lowest risk of incident PD (HR = 0.55; 95% CI: 0.44, 0.69), compared to those with low PA and poor sleep pattern; notably, participants with high PA but poor sleep pattern also gained benefit on PD risk reduction (HR = 0.74; 95% CI: 0.55, 0.99). CONCLUSIONS: Both high PA and ideal sleep pattern were independently associated with lower risk of developing PD, and those with both high PA level and ideal sleep pattern had the lowest risk. Our results suggest that improving PA levels and sleep quality may be promising intervention targets for the prevention of PD.


Assuntos
Doença de Parkinson , Humanos , Estudos de Coortes , Doença de Parkinson/epidemiologia , Sono , Exercício Físico , Comportamento de Redução do Risco , Fatores de Risco
6.
Bioorg Chem ; 143: 107044, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38134522

RESUMO

Musashi1 and Musashi2 are RNA-binding proteins originally found in drosophila, in which they play a crucial developmental role. These proteins are pivotal in the maintenance and differentiation of stem cells in other organisms. Research has confirmed that the Musashi proteins are highly involved in cell signal-transduction pathways such as Notch and TGF-ß. These signaling pathways are related to the induction and development of cancers, such as breast cancer, leukemia, hepatoma and liver cancer. In this review we focus on how Musashi proteins interact with molecules in different signaling pathways in various cancers and how they affect the physiological functions of these pathways. We further illustrate the status quo of Musashi proteins-targeted therapies and predict the target RNA regions that Musashi proteins interact with, in the hope of exploring the prospect of the design of Musashi protein-targeted medicines.


Assuntos
Química Farmacêutica , Neoplasias , Humanos , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Proteínas de Ligação a RNA/metabolismo , Neoplasias/tratamento farmacológico , RNA
7.
BMC Psychiatry ; 24(1): 431, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38858633

RESUMO

BACKGROUND: Depression is a prevalent mental health problem in postmenopausal women. Given its significant impact on the quality of life and overall well-being of postmenopausal women, there is need for a comprehensive review and meta-analysis of the existing research globally. This systematic review and meta-analysis evaluated the global prevalence of depression and potential associated factors in postmenopausal women. METHODS: The Cochrane Library, PubMed, EMBASE, Web of Science, MEDLINE, and PsycINFO databases were systematically searched from inception to March 22, 2023. The meta-analysis used the random-effects model to calculate the prevalence of depression rates and associated factors. In addition, subgroup analysis and sensitivity analysis were performed. Publication bias was assessed using funnel plots, Egger's test, and nonparametric trim-and-fill tests. RESULTS: The meta-analysis included 50 studies that involved 385,092 postmenopausal women. The prevalence of depression in postmenopausal women was 28.00% (95% CI, 25.80-30.10). Among the factors relevant to depression among postmenopausal women, marital status (OR: 2.03, 95%CI: 1.33-3.11), history of mental illness (OR: 2.31, 95%CI: 1.50-3.57), chronic disease (OR: 3.13, 95%CI: 2.20-4.44), menstrual cycle (OR: 1.42, 95%CI: 1.17-1.72), abortion numbers (OR: 1.59, 95%CI: 1.40-1.80), menopausal symptoms (OR: 2.10, 95%CI: 1.52-2.90), and hormone replacement therapy (OR: 1.76, 95%CI: 1.31-2.35) were risk factors, while physical activity (OR: 0.56, 95%CI: 0.53-0.59), number of breastfed infants (OR: 0.43, 95%CI: 0.19-0.97), menopause age (OR: 0.44, 95%CI: 0.37-0.51) were preventive factors. CONCLUSIONS: This study demonstrated that the prevalence of postmenopausal depression is high, and some risk factors and protective factors associated with it have been identified. It is necessary to improve screening and management and optimize prevention and intervention strategies to reduce the harmful effects of postmenopausal depression.


Assuntos
Pós-Menopausa , Humanos , Pós-Menopausa/psicologia , Feminino , Prevalência , Fatores de Risco , Depressão/epidemiologia , Transtorno Depressivo/epidemiologia
8.
BMC Womens Health ; 24(1): 126, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38365686

RESUMO

OBJECTIVE: To compare the application of sequential embryo transfer, cleavage embryo transfer, and blastocyst transfer combined with intrauterine perfusion in frozen-thawed embryo transfer cycles in patients with recurrent implantation failure to provide a reference for reproductive clinicians. METHODS: The 166 patients who underwent frozen-thawed embryo transfer due to recurrent implantation failure in the reproductive center from January 2021 to March 2022 were retrospectively analyzed. According to the different embryos transferred, they were divided into cleavage embryo transfer groups (72 cases in Group A), blastocyst transfer group (29 cases in Group B), and sequential transfer group (65 cases in Group C). All three groups were treated with intrauterine perfusion 5 days before embryo transfer. The general data and clinical pregnancy outcome indicators, such as embryo implantation rate, clinical pregnancy rate, ongoing pregnancy rate, live birth rate, twin rate, were compared among the three groups. RESULTS: The embryo implantation rate (53.1%), clinical pregnancy rate (76.9%), ongoing pregnancy rate (67.7%) and live birth rate(66.15%) in the sequential transfer group were significantly higher than those in the other two groups (P < 0.05), and the ectopic pregnancy rate was lower in the sequential transfer group. CONCLUSION: Sequential transfer combined with intrauterine perfusion partially improves clinical pregnancy outcomes and reduces the risk of ectopic pregnancy in frozen embryo cycle transfers in patients with recurrent implantation failure, which may be a favourable transfer reference strategy for patients with recurrent implantation failure.


Assuntos
Resultado da Gravidez , Gravidez Ectópica , Feminino , Gravidez , Humanos , Estudos Retrospectivos , Transferência Embrionária , Implantação do Embrião , Taxa de Gravidez , Gravidez Ectópica/etiologia , Perfusão , Fertilização in vitro
9.
Proc Natl Acad Sci U S A ; 118(21)2021 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-34001592

RESUMO

Functional biomolecules, such as RNA, encapsulated inside a protocellular membrane are believed to have comprised a very early, critical stage in the evolution of life, since membrane vesicles allow selective permeability and create a unit of selection enabling cooperative phenotypes. The biophysical environment inside a protocell would differ fundamentally from bulk solution due to the microscopic confinement. However, the effect of the encapsulated environment on ribozyme evolution has not been previously studied experimentally. Here, we examine the effect of encapsulation inside model protocells on the self-aminoacylation activity of tens of thousands of RNA sequences using a high-throughput sequencing assay. We find that encapsulation of these ribozymes generally increases their activity, giving encapsulated sequences an advantage over nonencapsulated sequences in an amphiphile-rich environment. In addition, highly active ribozymes benefit disproportionately more from encapsulation. The asymmetry in fitness gain broadens the distribution of fitness in the system. Consistent with Fisher's fundamental theorem of natural selection, encapsulation therefore leads to faster adaptation when the RNAs are encapsulated inside a protocell during in vitro selection. Thus, protocells would not only provide a compartmentalization function but also promote activity and evolutionary adaptation during the origin of life.


Assuntos
Células Artificiais/enzimologia , Compartimento Celular , Modelos Biológicos , Origem da Vida , RNA Catalítico/metabolismo , Sequência de Bases , Evolução Molecular , Ensaios de Triagem em Larga Escala , Cinética , Seleção Genética , Termodinâmica
10.
PLoS Genet ; 17(7): e1009675, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34324497

RESUMO

Emerging evidence indicates that tRNA-derived small RNAs (tsRNAs) are involved in fine-tuning gene expression and become dysregulated in various cancers. We recently showed that the 22nt LeuCAG3´tsRNA from the 3´ end of tRNALeu is required for efficient translation of a ribosomal protein mRNA and ribosome biogenesis. Inactivation of this 3´tsRNA induced apoptosis in rapidly dividing cells and suppressed the growth of a patient-derived orthotopic hepatocellular carcinoma in mice. The mechanism involved in the generation of the 3´tsRNAs remains elusive and it is unclear if the 3´-ends of 3´tsRNAs are aminoacylated. Here we report an enzymatic method utilizing exonuclease T to determine the 3´charging status of tRNAs and tsRNAs. Our results showed that the LeuCAG3´tsRNA, and two other 3´tsRNAs are fully aminoacylated. When the leucyl-tRNA synthetase (LARS1) was inhibited, there was no change in the total tRNALeu concentration but a reduction in both the charged tRNALeu and LeuCAG3´tsRNA, suggesting the 3´tsRNAs are fully charged and originated solely from the charged mature tRNA. Altering LARS1 expression or the expression of various tRNALeu mutants were also shown to affect the generation of the LeuCAG3´tsRNA further suggesting they are created in a highly regulated process. The fact that the 3´tsRNAs are aminoacylated and their production is regulated provides additional insights into their importance in post-transcriptional gene regulation that includes coordinating the production of the protein synthetic machinery.


Assuntos
RNA de Transferência/biossíntese , RNA de Transferência/genética , Aminoacilação de RNA de Transferência/genética , Aminoácidos/genética , Expressão Gênica/genética , Regulação da Expressão Gênica/genética , Células HeLa , Humanos , Leucina/genética , Leucina/metabolismo , Processamento Pós-Transcricional do RNA , Pequeno RNA não Traduzido/genética , Pequeno RNA não Traduzido/metabolismo , RNA de Transferência/metabolismo , Proteínas Ribossômicas , Aminoacilação de RNA de Transferência/fisiologia
11.
Sensors (Basel) ; 24(6)2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38544266

RESUMO

With the development of IoT technology and 5G massive machine-type communication, the 3GPP standardization body considered as viable the integration of Narrowband Internet of Things (NB-IoT) in low Earth orbit (LEO) satellite-based architectures. However, the presence of the LEO satellite channel comes up with new challenges for the NB-IoT random access procedures and coverage enhancement mechanism. In this paper, an Adaptive Coverage Enhancement (ACE) method is proposed to meet the requirement of random access parameter configurations for diverse applications. Based on stochastic geometry theory, an expression of random access channel (RACH) success probability is derived for LEO satellite-based NB-IoT networks. On the basis of a power consumption model of the NB-IoT terminal, a multi-objective optimization problem is formulated to trade-off RACH success probability and power consumption. To solve this multi-objective optimization problem, we employ the Non-dominated Sorting Genetic Algorithms-II (NSGA-II) method to obtain the Pareto-front solution set. According to different application requirements, we also design a random access parameter configuration method to minimize the power consumption under the constraints of RACH success probability requirements. Simulation results show that the maximum number of repetitions and back-off window size have a great influence on the system performance and their value ranges should be set within [4, 18] and [0, 2048]. The power consumption of coverage enhancement with ACE is about 58% lower than that of the 3GPP proposed model. All this research together provides good reference for the scale deployment of NB-IoT in LEO satellite networks.

12.
J Am Chem Soc ; 145(29): 15971-15980, 2023 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-37435826

RESUMO

The encoding step of translation involves attachment of amino acids to cognate tRNAs by aminoacyl-tRNA synthetases, themselves the product of coded peptide synthesis. So, the question arises─before these enzymes evolved, how were primordial tRNAs selectively aminoacylated? Here, we demonstrate enzyme-free, sequence-dependent, chemoselective aminoacylation of RNA. We investigated two potentially prebiotic routes to aminoacyl-tRNA acceptor stem-overhang mimics and analyzed those oligonucleotides undergoing the most efficient aminoacylation. Overhang sequences do not significantly influence the chemoselectivity of aminoacylation by either route. For aminoacyl-transfer from a mixed anhydride donor strand, the chemoselectivity and stereoselectivity of aminoacylation depend on the terminal three base pairs of the stem. The results support early suggestions of a second genetic code in the acceptor stem.


Assuntos
Aminoacil-tRNA Sintetases , RNA , RNA/metabolismo , Aminoacilação , Sequência de Bases , Código Genético , RNA de Transferência/química , Aminoacil-tRNA Sintetases/metabolismo , Conformação de Ácido Nucleico
13.
BMC Plant Biol ; 23(1): 259, 2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37189063

RESUMO

BACKGROUND: Human-guided crop domestication has lasted for more than 10,000 years. In terms of the domestication and breeding of vegetables, cellulose content in edible tissues is one of the most important traits. Primulina eburnea is a recently developed calcium-rich vegetable with a high soluble and bioavailable calcium content in its leaves. However, the high cellulose content in the leaves hampers the taste, and no research has been reported on the genetic basis of cellulose biosynthesis in this calcium-rich vegetable. RESULTS: We identified 36 cellulose biosynthesis-involved genes belonging to eight gene families in the P. eburnea genome. The cellulose accumulated decreasingly throughout leaf development. Nineteen genes were considered core genes in cellulose biosynthesis, which were highly expressed in buds but lowly expressed in mature leaves. In the nitrogen fertilization experiment, exogenous nitrogen decreased the cellulose content in the buds. The expressing pattern of 14 genes were consistent with phenotypic variation in the nitrogen fertilization experiment, and thus they were proposed as cellulose toolbox genes. CONCLUSIONS: The present study provides a strong basis for the subsequent functional research of cellulose biosynthesis-involved genes in P. eburnea, and provides a reference for breeding and/or engineering this calcium-rich vegetable with decreased leaf cellulose content to improve the taste.


Assuntos
Cálcio , Celulose , Humanos , Verduras , Melhoramento Vegetal , Nitrogênio
14.
J Microsc ; 291(2): 186-196, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37268302

RESUMO

Commercial electron backscatter diffraction (EBSD) systems generally use interplanar angle matching for pattern indexing, and thus, they are unable to distinguish between some similar phases with close interplanar angles, such as Al and Si. The interplanar spacing is more diagnostic but generally difficult to apply in pattern indexing because it lacks precision. In this study, we proposed an efficient approach for accurately measuring interplanar spacing by correcting the reciprocal-lattice vector (RLV). The phase discrimination of Al and Si was performed by interplanar spacing matching. The Kikuchi bands were identified automatically by the self-developed method using pattern rotation combined with grey gradient recognition without the help of human eyes. The reliable RLV relationship was extracted by accurately drawing reciprocal-lattice vectors. The lengths of RLVs were corrected, and then the RLVs were used for evaluating lattice spacing. The results of five Kikuchi patterns with different clarity showed that this new method reduced the average error of interplanar spacings by 50.611% and achieved an average accuracy of 1.644% for lattice spacing calculation. The method could distinguish structures with a difference in lattice spacing of at least 3.3%. This method was also effective for fuzzy patterns and partially missing Kikuchi bands and might be used as a new strategy for improving the calculation accuracy of lattice spacing for fuzzy patterns. The method did not have additional requirements concerning the number of detected Kikuchi bands and poles. The accuracy of lattice spacing could be effectively improved by correcting the RLVs based on routine pattern recognition. This method might be used as an auxiliary approach to differentiate between similar phases and is well-adapted to the existing commercial EBSD system.

15.
Thromb J ; 21(1): 19, 2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36782246

RESUMO

BACKGROUND: The use of cardiac implantable electronic devices has grown substantially over the past two decades, lead-related vascular issues are commonly encountered in clinical practice. Superior vena cava (SVC) syndrome due to pacemaker leads is an uncommon complication. Anticoagulation remains the mainstay of therapy to restore some degree of patency and relieve swelling. However, there are limited clinical trials on direct oral anticoagulants (DOACs). CASE PRESENTATION: We report a case of an 80-year-old man who developed SVC syndrome after transvenous pacemaker implantation with symptoms of obstruction that were significantly relieved after four months of DOACs. His symptoms had completely resolved nine months later. CONCLUSIONS: DOACs are effective in the treatment of SVC syndrome after pacemaker implantation, representing an important new approach. It is a very good choice for patients who do not want to undergo interventional therapy.

16.
Bioorg Chem ; 139: 106686, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37399616

RESUMO

Since most tumors become resistant to drugs in a gradual and irreversible manner, making treatment less effective over time, anticancer drugs require continuous development. Peptoids are a class of peptidomimetics that can be easily synthesized and optimized. They exhibit a number of unique characteristics, including protease resistance, non-immunogenicity, do not interfere with peptide functionality and skeleton polarity, and can adopt different conformations. They have been studied for their efficacy in different cancer therapies, and can be considered as a promising alternative molecular category for the development of anticancer drugs. Herein, we discuss the extensive recent advances in peptoids and peptoid hybrids in the treatment of cancers such as prostate, breast, lung, and other ones, in the hope of providing a reference for the further development of peptoid anticancer drugs.


Assuntos
Antineoplásicos , Peptoides , Masculino , Humanos , Peptoides/farmacologia , Peptoides/química , Peptídeos , Conformação Molecular , Antineoplásicos/química , Peptídeo Hidrolases
17.
Plant Dis ; 2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37682221

RESUMO

Multiple species of Streptomyces cause common scab disease in potato (Solanum tuberosum) (Kämpfer et al. 1991). Potato tubers (cv. Jinshu1 #5 and Longshu #6) with severe pitted common scab symptoms were observed from two farms in Chaozhou in Shanxi Province and in Tianzhu in Gansu Province during the national disease survey of bacterial diseases of potatoes in 2021. The disease incidence was around 30% on the 6.7 ha of the Chaozhou farm and 10% on the 0.7 ha on the Tianzhu farm. Three tubers with scab symptoms were surface disinfested with 3% sodium hypochlorite for 1 min. The symptomatic tissue was then ground in sterile water. Serially diluted ground samples were cultured on Streptomyces ISP Medium 5 agar plates (Shirling and Gottlieb 1966) and incubated at 280C for 5 days. Eight pure Streptomyces colonies were obtained and sequenced for identification using the universal 16S rRNA gene primers 27F (5'-AGAGTTTGATCMTGGCTCAG-3') and 1492R (5'-TACGGYTACCTTGTTACGACTT-3') (Monciardini et al. 2002) by colony PCR. Blast results of the sequences against the NCBI GenBank for the eight isolates, ZRIMU1508, ZRIMU1510, ZRIMU1511, ZRIMU1512, ZRIMU1514, ZRIMU1515, ZRIMU1516 and ZRIMU1530 (Accession numbers: OP941573 - OP941580), showed more than 99% sequence identity to S. niveiscabiei NRRLB-24457T type strain. Additionally, 12 housekeeping gene sequences, acnA (OP997624 - OP997625), atpD (OP997622 - OP997623), dnaN (OP997620 - OP997621), gap (OP997618 - OP997619), gyrA (OP997614 - OP997615), gyrB (OP997612 - OP997613), infB (OP997610- OP997611), mdh (OP997608 - OP997609), recA (OP997602 - OP997603), rplB (OP997600 - OP997601), rpoB (OP997598- OP997599), and trpB (OP997594 - OP997595), were extracted from the genome sequences of two strains, ZRIMU1510 and ZRIMU1530, and uploaded to GenBank. Genes for pathogenicity, txtA (OP997593 - OP997594), tomA (OP997596 - OP997597) and Nec1(OP997606 - OP997607), were also identified from the genome sequence and uploaded to GenBank. The housekeeping genes and the pathogenicity genes showed over 98% identity with S. niveiscabiei. Phylogenetic trees were constructed using concatenated housekeeping gene sequences (Kumar et al. 1994) and the cladogram showed that the isolates ZRIMU1510 and ZRIMU1530 grouped with the type strain NRRLB-24457T. Pathogenicity tests were done by drench application of 100 ml spore suspensions (104 CFU/ml) of ZRIMU1530, ZRIMU1510, or phosphate buffer into pots with potato plants (cv. Favorita) grown in potting mix. Five tubers were planted and inoculated with each pathogen or phosphate buffer as the negative control. The plants were then placed in a greenhouse with 12 h of light per day, irrigated regularly, and harvested after 3 months. The newly formed tubers were checked for disease symptoms. Tubers from pots inoculated with ZRIMU1530 and ZRIMU1510 exhibited typical symptoms of common scab with raised corky lesions with deep pits, but the negative controls remained asymptomatic. The pathogens were reisolated from the lesions and confirmed to be identical to the original isolates by 16S rRNA gene sequences, thus completing Koch's postulates. The pot experiment was conducted twice: first in May 2022 and second in February 2023. To our knowledge, this is the first report of S. niveiscabiei causing common scab of potato in Shanxi and Gansu, China. S. niveiscabiei was first reported in Korea (Park et al. 2003) and this report will draw attention to the study and management of scab pathogens in China.

18.
Phytochem Anal ; 34(7): 830-841, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36843182

RESUMO

BACKGROUND: Semen Aesculi, a traditional Chinese herbal medicine, has a long history of use for treating chest and abdominal pain with distension. In addition, the horse chestnut (Aesculus hippocastanum L.) is another species of Aesculus in Europe and has notable clinical significance in alleviating chronic venous insufficiency, hemorrhoids, and postoperative edema. Thus, highlighting the comparative study of Semen Aesculi and horse chestnut may broaden clinical applications. OBJECTIVES: To conduct a comprehensive comparative analysis on the chemical profiling of these two varieties and determine whether they have equivalent clinical efficacy by integrating plant metabolomics and multivariate statistical methods. METHODS: Initially, a comprehensive characterisation was performed using ultra-performance liquid chromatography quadrupole time-of-flight tandem mass spectrometry (UPLC-QTOF-MS/MS) platform, and in total 44 active ingredients were identified. Then, untargeted metabolomics combined with principal component analysis (PCA) and partial least squares-discriminant analysis (PLS-DA) was applied for the discrimination of a German species and three official Chinese species. Next, 24 marker compounds responsible for the discrimination of different species were screened out and used to predict the species of unknown samples by genetic algorithm-optimised support vector machine (GA-SVM) with a high prediction accuracy. Finally, a heatmap visualisation was employed for clarifying the distribution of the identified active ingredients. RESULTS: The three species of Chinese Semen Aesculi showed distinct separation from each other, while European horse chestnut and Aesculus chinensis Bunge were similar in chemical composition. CONCLUSIONS: This work provided experimental evidence for further expanding the clinical application of Chinese Semen Aesculi and promoted the species identification and quality control of Semen Aesculi.


Assuntos
Aesculus , Espectrometria de Massas em Tandem/métodos , Quimiometria , Sementes , Metabolômica/métodos , Cromatografia Líquida de Alta Pressão/métodos
19.
Sensors (Basel) ; 23(7)2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-37050606

RESUMO

In this paper, an asynchronous collision-tolerant ACRDA scheme based on satellite-selection collaboration-beamforming (SC-ACRDA) is proposed to solve the avalanche effect caused by packet collision under random access (RA) high load in the low earth orbit (LEO) satellite Internet of Things (IoT) networks. A non-convex optimization problem is formulated to realize the satellite selection problem in multi-satellite collaboration-beamforming. To solve this problem, we employ the Charnes-Cooper transformation to transform a convex optimization problem. In addition, an iterative binary search algorithm is also designed to obtain the optimization parameter. Furthermore, we present a signal processing flow combined with ACRDA protocol and serial interference cancellation (SIC) to solve the packet collision problem effectively in the gateway station. Simulation results show that the proposed SC-ACRDA scheme can effectively solve the avalanche effect and improve the performance of the RA protocol in LEO satellite IoT networks compared with benchmark problems.

20.
Molecules ; 29(1)2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38202725

RESUMO

The hydrophilic polysaccharides (PS) were isolated and purified from the tuberous roots of Pseudostellaria heterophylla. The extraction process of PS from Pesudostellariae radix was optimized by single-factor experiments and orthogonal design. The extract was purified by DEAE cellulose column to obtain the pure polysaccharide PHP. Then PHP was treated with different intensities of sonication to study the effect of sonication on PHP's characteristics and its biological activity in vitro and in vivo. The results of this study revealed that ultrasound treatment did not significantly change the properties of PHP. Further, with the increase of ultrasound intensity, PHP enhanced the proliferation and phagocytosis of macrophage RAW264.7. Meanwhile, it could also significantly improve the body's antioxidant activity and immune function. The results of this study demonstrated that PHP has the potential as a food additive with enhanced antioxidant and immune functions, and its biological activities could be enhanced by sonication.


Assuntos
Antioxidantes , Caryophyllaceae , Antioxidantes/farmacologia , Aditivos Alimentares , Ultrassonografia , Polissacarídeos/farmacologia
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