pH-Dependence of the Optical Bio-sensor Based on DNA-carbon Nanotube

In 2006, Daniel A. Heller et al. [1] demonstrated that carbon nanotubes (CNNTs) wrapped with DNA can be placed inside living cells and detect trace amounts of harmful contaminants using near infrared light. This discovery could lead to new types of optical sensors and biomarkers at the sub cellular level. The working principle of this optical bio-sensor from DNA and CNNTs can be explained by a simple theoretical model which was introduced in [3]. In this paper, the pH-dependence of DNA and the pH-dependence of solution around CNNTs are shown by using data analysis method. By substituting them into the same model, the pH-dependence of DNA-wrapped CNNTs was elicited in this paper. The range of parameters for workable conditions of this bio-sensor was indicated that the solution should have pH from 6 to 9 and the concentration of ions should be more than a critical value. These results are according to the experimental data and the deduction about pH and salt concentration in solution. They are very useful as using such a new bio-sensor like this in living environment

Van Der Waals and Casimir Interactions of Some Graphene, Material Plate and CNTs Systems

The Van der Waals and Casimir interactions between graphene and a material plate are studied by using the Lifshitz theory and approximate expressions for the free energy and force. The reflection properties of electromagnetic oscillations on graphene are governed by specific boundary conditions imposed on the infinitely thin positively charged plasma sheet, carrying a continuous fluid with some mass and charge density. The obtained formulas are applied to the cases of a graphene interacting with Au plate. We calculated also the Casimir interaction between carbon nanotube single wall and Au plate. The comparision with other recently obtained theoretical results are made and the generalizations to more complicated carbon nanostructures are discussed

Serum free light-chain concentration and relationship with some characteristics of patients with multiple myeloma

Introduction: Quantifying serum free light-chain is a valuable test to determine the risk at the time of diagnosis, assess the response to treatment, and monitor the recurrence of multiple myeloma. Objective: To investigate the characteristics of serum free light-chain concentration and its relationship with some clinical and subclinical characteristics in patients with multiple myeloma. Methods: Descriptive, retrospective, non-controlled study was conducted, in 74 patients with multiple myeloma. All patients were completed with quantitative tests serum free light-chain κ, and serum free light-chain λ. Results: Intact immunoglobulin multiple myeloma accounted for most patients (81%). Most patients had abnormal serum free light-chain at the time of diagnosis (98.6%). High serum free light-chain concentration was correlated with M protein concentration > 3 g/dL (p< 0.05) and there was no statistically significant correlation between high serum free light-chain and other clinical and subclinical features. Conclusion: Most patients with multiple myeloma have an elevated serum free light-chain at admission time. Correlation of high serum free light-chain with increased serum M protein was noted

Gasdermin E Does Not Limit Apoptotic Cell Disassembly by Promoting Early Onset of Secondary Necrosis in Jurkat T Cells and THP-1 Monocytes

During the progression of necroptosis and pyroptosis, the plasma membrane will become permeabilized through the activation of mixed lineage kinase domain like pseudokinase (MLKL) or gasdermin D (GSDMD), respectively. Recently, the progression of apoptotic cells into secondary necrotic cells following membrane lysis was shown to be regulated by gasdermin E (GSDME, or DFNA5), a process dependent on caspase 3-mediated cleavage of GSDME. Notably, GSDME was also proposed to negatively regulate the disassembly of apoptotic cells into smaller membrane-bound vesicles known as apoptotic bodies (ApoBDs) by promoting earlier onset of membrane permeabilisation. The presence of a process downstream of caspase 3 that would actively drive cell lysis and limit cell disassembly during apoptosis is somewhat surprising as this could favor the release of proinflammatory intracellular contents and hinder efficient clearance of apoptotic materials. In contrast to the latter studies, we present here that GSDME is not involved in regulating secondary necrosis in human T cells and monocytes, and also unlikely in epithelial cells. Furthermore, GSDME is evidently not a negative regulator of apoptotic cell disassembly in our cell models. Thus, the function of GSDME in regulating membrane permeabilization and cell disassembly during apoptosis may be more limited

Moving beyond size and phosphatidylserine exposure: evidence for a diversity of apoptotic cell-derived extracellular vesicles in vitro

Apoptosis is a form of programmed cell death that occurs throughout life as part of normal development as well as pathologic processes including chronic inflammation and infection. Although the death of a cell is often considered as the only biological outcome of a cell committed to apoptosis, it is becoming increasingly clear that the dying cell can actively communicate with other cells via soluble factors as well as membrane-bound extracellular vesicles (EVs) to regulate processes including cell clearance, immunity and tissue repair. Compared to EVs generated from viable cells such as exosomes and microvesicles, apoptotic cell-derived EVs (ApoEVs) are less well defined and the basic criteria for ApoEV characterization have not been established in the field. In this study, we will examine the current understanding of ApoEVs, in particular, the ApoEV subtype called apoptotic bodies (ApoBDs). We described that a subset of ApoBDs can be larger than 5 μm and smaller than 1 μm based on flow cytometry and live time-lapse microscopy analysis, respectively. We also described that a subset of ApoBDs can expose a relatively low level of phosphatidylserine on its surface based on annexin A5 staining. Furthermore, we characterized the presence of caspase-cleaved proteins (in particular plasma membrane-associated or cytoplasmic proteins) in samples enriched in ApoBDs. Lastly, using a combination of biochemical-, live imaging- and flow cytometry-based approaches, we characterized the progressive lysis of ApoBDs. Taken together, these results extended our understanding of ApoBDs

Minimal information for studies of extracellular vesicles (MISEV2023): From basic to advanced approaches

Extracellular vesicles (EVs), through their complex cargo, can reflect the state of their cell of origin and change the functions and phenotypes of other cells. These features indicate strong biomarker and therapeutic potential and have generated broad interest, as evidenced by the steady year-on-year increase in the numbers of scientific publications about EVs. Important advances have been made in EV metrology and in understanding and applying EV biology. However, hurdles remain to realising the potential of EVs in domains ranging from basic biology to clinical applications due to challenges in EV nomenclature, separation from non-vesicular extracellular particles, characterisation and functional studies. To address the challenges and opportunities in this rapidly evolving field, the International Society for Extracellular Vesicles (ISEV) updates its 'Minimal Information for Studies of Extracellular Vesicles', which was first published in 2014 and then in 2018 as MISEV2014 and MISEV2018, respectively. The goal of the current document, MISEV2023, is to provide researchers with an updated snapshot of available approaches and their advantages and limitations for production, separation and characterisation of EVs from multiple sources, including cell culture, body fluids and solid tissues. In addition to presenting the latest state of the art in basic principles of EV research, this document also covers advanced techniques and approaches that are currently expanding the boundaries of the field. MISEV2023 also includes new sections on EV release and uptake and a brief discussion of in vivo approaches to study EVs. Compiling feedback from ISEV expert task forces and more than 1000 researchers, this document conveys the current state of EV research to facilitate robust scientific discoveries and move the field forward even more rapidly

Implementation of an adaptive voltage maximum power point tracking method on a Solar LED DC-DC converter for micro grid system

International audienc

Ảnh hưởng của quá trình tiền xử lý đến chất lượng cam Sành (Citrus sinensis) sấy dẻo

Cam sành là nguồn cung cấp dồi dào hợp chất tự nhiên có hoạt tính sinh học cao. Nghiên cứu phát triển các sản phẩm mới, đặc biệt là sản phẩm cam sấy dẻo, có thể tận dụng nguồn nguyên liệu cam sành dồi dào và cung cấp đầu ra bền vững cho sản xuất trong nước là vấn đề cần thiết. Tuy nhiên, vị đắng trong một số sản phẩm chế biến từ cam là một trong những vấn đề lớn của ngành công nghiệp chế biến. Do vậy, nghiên cứu giảm vị đắng trong cam sấy dẻo là vấn đề cần thiết. Mục tiêu của nghiên cứu là xác định ảnh hưởng của (i) loại hóa chất xử lý (NaOH, Na3C6H5O7, NaOH+Na3C6H5O7, NaCl và Na2CO3) và phương pháp tiền xử lý (ngâm trong dung dịch hóa chất sau đó chần hoặc chần trong dung dịch hóa chất); (ii) ảnh hưởng nồng độ của hóa chất xử lý (0, 50, 100, 150 và 200 ppm) đến khả năng giảm hàm lượng naringin và duy trì giá trị dinh dưỡng của sản phẩm cam sành sấy dẻo. Kết quả nghiên cứu cho thấy cam sành được chần trong dung dịch NaOH với nồng độ 150 ppm giúp giảm được hàm lượng naringin cao (từ 18,75 giảm còn 2,11 mg/100g). Hàm lượng polyphenol và vitamin C trong sản phẩm vẫn còn duy trì ở mức cao, tương ứng là 5,57 mgGAE/g and 71,71 mg/100 g