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“Earth summit mission 2022” is one of the landmark scientific research activities of the Second Tibetan Plateau Scientific Expedition and Research (STEP). This scientific expedition firstly used advanced technology and methods to detect vertical meteorological elements and produce forecasts for mountain climbing. The “Earth summit mission 2022” Qomolangma scientific expedition exceeded an altitude of over 8000 meters for the first time and carried out a comprehensive scientific investigation mission on the summit of Mt. Qomolangma. Among the participants, the westerly-monsoon synergy and influence team stationed in the Mt. Qomolangma region had two tasks: 1) detecting the vertical structure of the atmosphere for parameters such as wind, temperature, humidity, and pressure with advanced instruments for high-altitude detection at the Mt. Qomolangma base camp; and 2) observing extreme weather processes to ensure that members of the mountaineering team could successfully reach the top. Through this scientific expedition, a better understanding of the vertical structure and weather characteristics of the complex area of Mt. Qomolangma is gained.

Studies of electric effects in biological systems, from the work on action potential to studies on limb regeneration or wound healing, commonly focus on transitory behaviour and not on addressing the question of homeostasis. Here we use a microfluidic device to study how the homeostasis of confluent epithelial tissues is modified when a transepithelial potential difference that is different from the natural one is imposed on an epithelial layer. When the field direction matches the natural one, we can restore perfect confluence in an epithelial layer turned defective either by E-cadherin knockout or by weakening the cell–substrate adhesion; additionally, the tissue pushes on the substrate with kilopascal stress, inducing active-cell response such as death and differentiation. When the field is opposite, the tissue pulls with similar strengths, whereas homeostasis is destroyed by the perturbation of junctional actin and cell shapes, increased cell division rate and formation of mounds. Most of these observations can be quantitatively explained by an electrohydrodynamic theory involving local cytoplasmic electro-osmotic flows. We expect this work to motivate further studies on the long-time effects of electromechanical pathways with important tissue engineering applications.

AbstractThe aim of this study was to investigate the association between expressions of five periodontal pathogens (Actinobacillus actinomycetemcomitans(Aa), Porphyromonas gingivalis(Pg), Tannerella forsythensis(Tf), Treponema denticola(Td) and Prevotella intermedia(Pi) and the periodontal pocket depth (PD) in people suffering from periodontitis. A study of 1164 plaque samples from individuals with periodontitis were conducted by multiplex real-time quantitative fluorescence-polymerase chain reaction to evaluate the PD and loads of five periodontal pathogens. The total bacterial number did not differ significantly between people with different subtypes of periodontitis. However, expression of specific pathogens (Pg, Td, Tf, Pi) showed a significant increase with the development of periodontitis. Expression of Pg, Td and Tf showed close correlation between them as well as with PD. Analyses of receiver operating characteristic curves showed that expression of Pg, Td, Tf and Pi had good potential for grading periodontitis severity. We found a close correlation between the relative expression of Pg, Td and Tf and PD. Measuring expression of target bacteria in the oral cavity could facilitate the understanding of the role of bacteria in periodontitis. Taking the appropriate steps to eliminate these pathogens might aid the prevention of periodontitis development.

Background: The decline in the quantity and quality of mitochondria are closely associated with infertility, particularly in advanced maternal age. Transferring autologous mitochondria into the oocytes of infertile females represents an innovative and viable strategy for treating infertility, with no concerns regarding ethical considerations. As the donor cells of mitochondria, stem cells have biological advantages but research and evidence in this area are quite scarce. Methods: To screen out suitable human autologous ooplasmic mitochondrial donor cells, we performed comprehensive assessment of mitochondrial physiology, function and metabolic capacity on a varity of autologous adipose, marrow, and urine-derived mesenchymal stromal cells (ADSC, BMSC and USC) and ovarian germline granulosa cells (GC). Further, to explore the biosafety, effect and mechanism of stem cell-derived mitochondria transfer on human early embryo development, randomized in-vitro basic studies were performed in both of the young and aged oocytes from infertile females. Results: Compared with other types of mesenchymal stromal cells, USC demonstrated a non-fused spherical mitochondrial morphology and low oxidative stress status which resembled the oocyte stage. Moreover, USC mitochondrial content, activity and function were all higher than other cell types and less affected by age, and it also exhibited a biphasic metabolic pattern similar to the pre-implantation stage of embryonic development. After the biosafety identification of the USC mitochondrial genome, early embryos after USC mitochondrial transfer showed improvements in mitochondrial content, activity, and cytoplasmic Ca2+levels. Further, aging embryos also showed improvements in embryonic morphological indicators, euploidy rates, and oxidative stress status. Conclusion: Autologous non-invasively derived USC mitochondria transfer may be an effective strategy to improve embryonic development and metabolism, especially in infertile females with advanced age or repeated pregnancy failure. It provides evidence and possibility for the autologous treatment of infertile females without invasive and ethical concerns.

ABSTRACTIn this paper, we report the development of a label-free biosensor, based on surface plasmon resonance, for real-time monitoring of captured human CD4+T-cells, and their dynamic cytokine production upon specific antigen stimulation. Microarrays of CD4+T-cells, and interferon gamma (IFN-γ) specific antibody (Ab) spots were printed side by side onto the poly(OEGMA-co-HEMA) matrix. The placement of CD4+T-cells near the anti IFN-γ Ab-coated spots ensured a high local concentration of secreted IFN-γ for detection. We have demonstrated that this approach enables the detection of tuberculosis (TB) infection in clinical samples, with an overall sensitivity of 85.5% and an overall specificity of 97.7%.

Surface plasmon resonance (SPR) biosensor is a powerful tool for studying the kinetics of biomolecular interactions because they offer unique real-time and label-free measurement capabilities with high detection sensitivity. In the past two decades, SPR technology has been successfully commercialized and its performance has continuously been improved with lots of engineering efforts. In this review, we describe the recent advances in SPR technologies. The developments of SPR technologies focusing on detection speed, sensitivity, and portability are discussed in details. The incorporation of imaging techniques into SPR sensing is emphasized. In addition, our SPR imaging biosensors based on the scanning of wavelength by a solid-state tunable wavelength filter are highlighted. Finally, significant advances of the vast developments in nanotechnology-associated SPR sensing for sensitivity enhancements are also reviewed. It is hoped that this review will provide some insights for researchers who are interested in SPR sensing, and help them develop SPR sensors with better sensitivity and higher throughput.

Abstract: The “solidified liquid layer” model has been examined using a quartz crystal microbalance (QCM) with a polymeric matrix. The model is shown to give a reasonable explanation for the following experimental observations: (i) The opposite response of the QCM and surface plasmon resonance (SPR) for the activation process; (ii) the marked difference in the responses for IgG/anti-IgG interaction between QCM and SPR. Theoretical analysis and experimental results indicated that QCM is sensitive to the thickness change of the “solidified liquid layer” but not the mass of captured biomolecules (i.e., the immobilized mass), implying caution must be taken in interpreting QCM results.

We aimed to compare the clinical outcomes of pre-emptive angioplasty versus post-thrombotic percutaneous endovascular restoration of dysfunctional arteriovenous fistula (AVF).

A wavelength-multiplexing phase-sensitive surface plasmon resonance (SPR) imaging sensor offering wide dynamic detection range and microarray capability is reported. Phase detection is accomplished by performing self-interference between the s- and p- polarizations within the signal beam. A liquid crystal tunable filter is used to sequentially select the SPR excitation wavelength from a white light source. This wavelength-multiplexing approach enables fast detection of the sensor’s SPR phase response over a wide range of wavelengths, thereby covering literally any regions of interest within the SPR dip and thus maintaining the highest sensitivity point at all times. The phase-sensitive approach is particularly important for imaging SPR sensing applications because of its less stringent requirements for intensity signal-to-noise ratio, which also means the possibility of using uncooled modest resolution analog-to-digital conversion imaging devices. Experimental results demonstrate a resolution of 2.7×10^−7  RIU with a dynamic range of 0.0138 RIU.