工程技术最新文献

Genome editing tools have rapidly been adopted by plant scientists for crop improvement. Genome editing using a multiplex sgRNA-CRISPR/Cas9 genome editing system is a useful technique for crop improvement in monocot species. In this study, we utilized precise gene editing techniques to generate wheat 3'(2'), 5'-bisphosphate nucleotidase (TaSal1) mutants using a multiplex sgRNA-CRISPR/Cas9 genome editing system. Five active TaSal1 homologous genes were found in the genome of Giza168 in addition to another apparently inactive gene on chromosome 4A. Three gRNAs were designed and used to target exons 4, 5 and 7 of the five wheat TaSal1 genes. Among the 120 Giza168 transgenic plants, 41 lines exhibited mutations and produced heritable TaSal1 mutations in the M₁ progeny and 5 lines were full 5 gene knock-outs. These mutant plants exhibit a rolled-leaf phenotype in young leaves and bended stems, but there were no significant changes in the internode length and width, leaf morphology, and stem shape. Anatomical and scanning electron microscope studies of the young leaves of mutated TaSal1 lines showed closed stomata, increased stomata width and increase in the size of the bulliform cells. Sal1 mutant seedlings germinated and grew better on media containing polyethylene glycol than wildtype seedlings. Our results indicate that the application of the multiplex sgRNA-CRISPR/Cas9 genome editing is efficient tool for mutating more multiple TaSal1 loci in hexaploid wheat.

Herein, we investigated the phytochemical composition and antibacterial activities of the organic layers from biosynthesized silver nanoparticles (AgNPs). AgNPs were synthesized using Musa paradisiaca and Musa sapientum extracts. UV-vis absorption in the 400-450 nm range indicated surface plasmonic resonance peak of AgNPs. Samples analyses using dynamic light scattering and transmission electron microscopy revealed the presence of particles within nanometric ranges, with sizes of 30-140 nm and 8-40 nm, respectively. Fourier transform infrared (FTIR) unveiled the presence of several organic functional groups on the surface of AgNPs, indicating the presence of phytochemicals from plant extracts. Thin layer chromatography (TLC) of the phytochemicals (capping agents) from AgNPs identified multiple groups of secondary metabolites. These phytochemical capping agents exhibited antibacterial activities against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa, with minimum inhibitory concentrations ranging from 62.5 to 1000 µg/mL. Regardless of the bacterial species or plant parts (leaves or pseudo-stems), capping agents from M. sapientum nanoparticles displayed significantly enhanced antibacterial effectiveness compared to all other samples, including the raw plant extracts and biosynthesized capped and uncapped AgNPs. These results suggest the presence of antimicrobial phytochemicals on biosynthesized AgNPs, highlighting the promise of green nanoparticle synthesis as a valuable approach in bioprospecting antimicrobial agents.

Objective: This trial probed the correlation between miR-31 expression and endometrial receptivity (ER) in patients with repeated implantation failure (RIF) of in vitro fertilization and embryo transfer (IVF-ET).

Methods: A retrospective study of 80 infertility patients who underwent IVF-ET assisted conception treatment were divided into RIF group and normal pregnancy group (control group) according to the pregnancy outcome after embryo transfer. General information of both groups was collected. Endometrial tissues were collected in the middle luteal phase of the menstrual cycle before IVF-ET. miR-31 levels in endometrial tissues were measured, and endometrial tolerance indicator pulsatility index (PI), resistance index (RI), and endometrial thickness (Em) were detected. The correlation between endometrial miR-31 levels and ER indices was evaluated by Pearson method. ROC curves were utilized to analyze the efficacy of miR-31 in predicting RIF occurrence. The influencing factors of RIF were analyzed by binary Logistic regression.

Results: RIF patients had increased miR-31 expression level and endometrial tolerance indicator PI, and RI while decreased Em (p < 0.05). miR-31 in RIF patients was positively correlated with PI and RI, and negatively correlated with Em (p < 0.05). The area under the curve for miR-31 to predict the occurrence of RIF was 0.899, with a sensitivity of 0.750 and a specificity of 0.950. PI, RI, and miR-31 were risk factors for developing RIF in IVF-ET women, and Em was a protective factor (p < 0.05).

Conclusion: miR-31 in RIF patients is positively correlated with PI and RI, and negatively correlated with Em.

The signaling mechanisms active within mesenchymal stromal cells (MSCs) influence the composition of microvesicles (MVs) and exosomes (Exos) secreted by them. Previously, we showed that priming MSCs with a p38 pharmacological inhibitor (pMSCs) rejuvenates them and improves their ability to promote ex vivo hematopoietic stem cell (HSC) expansion. This study examined whether pMSCs exerted HSC-supportive ability via MVs (pMVs) and Exos (pExos). Our findings demonstrate distinct regulation of HSC fate by pMVs and pExos. pMVs promoted the expansion of long-term HSCs (LT-HSCs), distinguished by their robust self-renewal capacity and superior engraftment ability. In contrast, pExos facilitated expansion of short-term HSCs (ST-HSCs) with high proliferative and differentiation potential. Infusing a combination of pMVs- and pExos-expanded HSCs as a composite graft resulted in significantly higher HSC engraftment, emphasizing the synergistic interaction between LT- and ST-HSC populations. Gene expression studies, functional and phenotypic experiments showed that pMVs regulate HSC quiescence via the Egr1/Cdkn1a axis, while pExos control HSC proliferation via the Nfya/Cdkn1a axis. These findings provide insights into the molecular mechanisms underlying the differential regulation of HSC function by pMVs and pExos. It also proposes a composite graft strategy of using pMVs and pExos as "MSC-derived biologics" for improving the HSC transplantation success.

Bacterial infections associated with healthcare are a challenge on a global scale due to the high morbidity and mortality rates, especially those caused by multidrug-resistant isolates. Hospital textiles are abiotic surfaces that may serve as a means of disseminating and persisting microorganisms in hospitals, as microorganisms can remain viable on these surfaces for up to months. In this study, we employed a green synthesis approach utilizing guava leaf extract (Psidium guajava) to produce silver nanoparticles, which were then incorporated into a cotton fabric. Antimicrobial properties and the cytotoxicity of the functional textile were assessed. The finding indicated that the green synthesis method was efficient and resulted in a predominant population of nanoparticles with diameters ranging from 25 to 84 nm that were uniformly dispersed in the textile. The functional textile exhibited low toxicity and high antimicrobial efficiency, even against multidrug-resistant microorganisms of particular concern in hospital settings. Atomic force microscopy carried out evidenced invaginations in the cell wall of bacteria submitted to this textile, suggesting surface damage as an important mechanism of action silver nanoparticles incorporated.

Triple-negative breast cancer (TNBC) is a significant global health issue, with high mortality rates. The chemotherapeutic drugs currently used for TNBC have significant side effects, impacting both normal and cancer cells. In this study, we investigated a potential use of fruit peel extract of Psidium guajava (PGP) encapsulated with chitosan nanoparticles (CSNPs) to combat TNBC. The synthesized PGP-CSNPs were characterized using UV-vis spectroscopy, Fourier transform infra-red (FTIR) spectroscopy, TEM and GC-MS. The maximum loading capacity and encapsulation efficacy of PGP-CSNPs were found to be 72.5 ± 0.49% and 92.9 ± 0.10%, respectively. Furthermore, in vitro cytotoxicity was assessed, and the IC₅₀ value for PGP-CSNPs was 50.13 µg/mL. It was observed that PGP-CSNPs could induce apoptosis in MDA-MB-231 cells in dose-dependent manner. Furthermore, molecular docking was performed for bioactive compounds retrieved from PGP-CSNPs against human tumour suppressor proteins Bcl2, and results showed that the PGP-CSNPs had lower binding energy than cisplatin. This suggests that, the synthesized PGP-CSNPs have the potential to serve as a therapeutic agent for tackling TNBC. However, to validate its efficacy in human therapy, furthermore pre-clinical and clinical procedures should be examined, as this is an ongoing and significant step towards developing an effective and safe anticancer drug.

Malic acid markedly affects watermelon flavor. Reducing the malic acid content can significantly increase the sweetness of watermelon. An effective solution strategy is to reduce watermelon malic acid content through molecular breeding technology. In this study, we measured the TSS and pH of six watermelon varieties at four growth nodes. The TSS content was very low at 10 DAP and accumulated rapidly at 18, 26, and 34 DAP. Three phosphoenolpyruvate carboxykinase (PEPCK) genes of watermelon were identified and analyzed. The ClaPEPCK4 expression was inversely proportional to malate content variations in fruits. In transgenic watermelon plants, overexpressing the ClaPEPCK4 gene, malic acid content markedly decreased. In the knockout transgenic watermelon plants, two SNP mutations and one base deletion occurred in the ClaPEPCK4 gene, with the malic acid content in the leaves increasing considerably and the PEPCK enzyme activity reduced to half of the wild-type. It is interesting that the ClaPEPCK4 gene triggered the closure of leaf stomata under dark conditions in the knockout transgenic plants, which indicated its involvement in stomatal movement. In conclusion, this study provides a gene target ClaPEPCK4 for creating innovative new high-sweetness watermelon varieties.

Motor planning plays a pivotal role in daily life. Transcutaneous auricular vagus nerve stimulation (taVNS) has been demonstrated to enhance decision-making efficiency, illustrating its potential use in cognitive modulation. However, current research primarily focuses on behavioral and single-modal electrophysiological signal, such as electroencephalography (EEG) and electrocardiography (ECG). To investigate the effect of taVNS on motor planning, a total of 21 subjects were recruited for this study and were divided into two groups: active group (n = 10) and sham group (n = 11). Each subject was required to be involved in a single-blind, sham-controlled, between-subject end-state comfort (ESC) experiment. The study compared behavioral indicators and electrophysiological features before and following taVNS. The results indicated a notable reduction in reaction time and an appreciable increase in the proportion of end-state comfort among the participants following taVNS, accompanied by notable alterations in motor-related cortical potential (MRCP) amplitude, low-frequency power of HRV (LF), and cortico-cardiac coherence, particularly in the parietal and occipital regions. These findings show that taVNS may impact the brain and heart, potentially enhancing their interaction, and improve participants' ability of motor planning.

Identifying the cognitive state can help educators understand the evolving thought processes of learners, and it is important in promoting the development of higher-order thinking skills (HOTS). Cognitive neuroscience research identifies cognitive states by designing experimental tasks and recording electroencephalography (EEG) signals during task performance. However, most of the previous studies primarily concentrated on extracting features from individual channels in single-type tasks, ignoring the interconnection across channels. In this study, three learning activities (i.e., video watching activity, keyword extracting activity, and essay creating activity) were designed based on a revised Bloom's taxonomy and the Interactive-Constructive-Active-Passive framework and used with 31 college students. The EEG signals were recorded when they were engaged in these activities. First, whole-brain network temporal dynamics were characterized by EEG microstate sequence analysis. Such dynamic changes rely on learning activity and corresponding functional brain systems. Subsequently, phase locking value was used to construct synchrony-based functional brain networks. The network characteristics were extracted to be inputted into different machine learning classifiers: Support Vector Machine, K-Nearest Neighbour, Random Forest, and eXtreme Gradient Boosting (XGBoost). XGBoost showed superior performance in the classification of cognitive states, with an accuracy of 88.07%. Furthermore, SHapley Additive exPlanations (SHAP) was adopted to reveal the connections between different brain regions that contributed to the classification of cognitive state. SHAP analysis reveals that the connections in the frontal, temporal, and central regions are most important for the high cognitive state. Collectively, this study may provide further evidence for educators to design cognitive-guided instructional activities to enhance learners' HOTS.

To feed the world's expanding population, crop breeders need to increase agricultural productivity and expand major crops base. Orphan crops are indigenously important crops with great potential because they are climate resilient, highly nutritious, contain nutraceutical compounds, and can improve the livelihood of smallholder farmers and consumers, but they have received little or no scientific attention. This review article examines several research and developmental strategies for hastening the improvement of these crops so that they can effectively play their role in securing food and nutrition. The integration of both research and developmental approaches will open up modern opportunities for crop improvement. We summarized ways in which advanced tools in phenotyping and genotyping, using high-throughput processes, can be used to accelerate their improvement. Finally, we suggest roles the genebanks can play in improving orphan crops, as the utilization of plant genetic resources is important for the genetic improvement of a crop.