scholarly journals Technical and Methodological Aspects of Cell-Free Nucleic Acids Analyzes

2020 ◽  
Vol 21 (22) ◽  
pp. 8634
Author(s):  
Zuzana Pös ◽  
Ondrej Pös ◽  
Jakub Styk ◽  
Angelika Mocova ◽  
Lucia Strieskova ◽  
...  

Analyzes of cell-free nucleic acids (cfNAs) have shown huge potential in many biomedical applications, gradually entering several fields of research and everyday clinical care. Many biological properties of cfNAs can be informative to gain deeper insights into the function of the organism, such as their different types (DNA, RNAs) and subtypes (gDNA, mtDNA, bacterial DNA, miRNAs, etc.), forms (naked or vesicle bound NAs), fragmentation profiles, sequence composition, epigenetic modifications, and many others. On the other hand, the workflows of their analyzes comprise many important steps, from sample collection, storage and transportation, through extraction and laboratory analysis, up to bioinformatic analyzes and statistical evaluations, where each of these steps has the potential to affect the outcome and informational value of the performed analyzes. There are, however, no universal or standard protocols on how to exactly proceed when analyzing different cfNAs for different applications, at least according to our best knowledge. We decided therefore to prepare an overview of the available literature and products commercialized for cfNAs processing, in an attempt to summarize the benefits and limitations of the currently available approaches, devices, consumables, and protocols, together with various factors influencing the workflow, its processes, and outcomes.

2013 ◽  
Vol 3 (1) ◽  
Author(s):  
Mayer F. Wowor

Abstract: Efficient and accurate diagnosis of dengue is of primary importance for clinical care, surveillance activities, outbreak control, pathogenesis, academic research, vaccine development, and clinical trials. Laboratory diagnostic methods for confirming dengue virus infection may involve detection of the viruses, viral nucleic acids, antigens and antibodies, or a combination of these techniques. After the onset of illness, the virus can be detected in serum, plasma, circulating blood cells, and other tissues for 4–5 days. During the early stage of the disease, virus isolation and the detection of viral nucleic acids or antigens, can be used to confirm the diagnosis of dengue infection. NS1 antigen appears as early as day 1 after the onset of fever, and declines to undetectable levels after day 5–6. At the end of the acute phase of infection, a serological test is the method of choice for diagnosis. A range of laboratory diagnostic methods has been developed to support patient management and disease control. The choice of diagnostic method depends on the purpose for which the test is done, available  laboratory facilities and technical expertise, costs, and the time of sample collection. Keywords: laboratory diagnostic methods, acute phase, NS1 antigen     Abstrak: Diagnosis dengue yang efisien dan akurat adalah hal yang paling penting  untuk proses perawatan di klinik, aktivitas surveilens, kontrol penularan penyakit, patogenesis, penelitian akademik, pengembangan vaksin dan percobaan-percobaan klinis. Metode diagnosis laboratorium untuk mengonfirmasi adanya infeksi virus dengue dapat meliputi deteksi virus dengue, asam nukleat virus, antigen dan antibodi, atau kombinasi dari teknik-teknik tersebut. Setelah serangan penyakit, virus dapat dideteksi dalam serum, plasma, sel-sel darah yang bersirkulasi, dan di jaringan lain dalam waktu 4-5 hari. Selama tahap awal dari penyakit, isolasi virus, asam nukleat virus, atau deteksi antigen dapat digunakan untuk diagnosis infeksi. Antigen NS1 muncul pada hari pertama setelah serangan demam dan menurun ke tingkat tidak terdeteksi setelah 5-6 hari. Pada akhir fase akut infeksi, serologi adalah metode pilihan untuk diagnosis. Metode diagnosis laboratorium telah berkembang untuk menunjang penanganan pasien dan kontrol penyakit. Pilihan untuk metode diagnosis bergantung pada tujuan tes dilakukan, fasilitas laboratorium dan tenaga ahli yang tersedia, biaya, dan saat sampel dikumpulkan. Kata kunci: metode diagnosis laboratorium, fase akut, antigen NS1


2020 ◽  
Vol 27 (9) ◽  
pp. 1387-1404 ◽  
Author(s):  
Karishma Biswas ◽  
Humaira Ilyas ◽  
Aritreyee Datta ◽  
Anirban Bhunia

Antimicrobial Peptides (AMPs), within their realm incorporate a diverse group of structurally and functionally varied peptides, playing crucial roles in innate immunity. Over the last few decades, the field of AMP has seen a huge upsurge, mainly owing to the generation of the so-called drug resistant ‘superbugs’ as well as limitations associated with the existing antimicrobial agents. Due to their resilient biological properties, AMPs can very well form the sustainable alternative for nextgeneration therapeutic agents. Certain drawbacks associated with existing AMPs are, however, issues of major concern, circumventing which are imperative. These limitations mainly include proteolytic cleavage and hence poor stability inside the biological systems, reduced activity due to inadequate interaction with the microbial membrane, and ineffectiveness because of inappropriate delivery among others. In this context, the application of naturally occurring AMPs as an efficient prototype for generating various synthetic and designed counterparts has evolved as a new avenue in peptide-based therapy. Such designing approaches help to overcome the drawbacks of the parent AMPs while retaining the inherent activity. In this review, we summarize some of the basic NMR structure based approaches and techniques which aid in improving the activity of AMPs, using the example of a 16-residue dengue virus fusion protein derived peptide, VG16KRKP. Using first principle based designing technique and high resolution NMR-based structure characterization we validate different types of modifications of VG16KRKP, highlighting key motifs, which optimize its activity. The approaches and designing techniques presented can support our peers in their drug development work.


2020 ◽  
Vol 21 (4) ◽  
pp. 429-438 ◽  
Author(s):  
Bruno Casciaro ◽  
Francesca Ghirga ◽  
Deborah Quaglio ◽  
Maria Luisa Mangoni

Cationic antimicrobial peptides (AMPs) are an interesting class of gene-encoded molecules endowed with a broad-spectrum of anti-infective activity and immunomodulatory properties. They represent promising candidates for the development of new antibiotics, mainly due to their membraneperturbing mechanism of action that very rarely induces microbial resistance. However, bringing AMPs into the clinical field is hampered by some intrinsic limitations, encompassing low peptide bioavailability at the target site and high peptide susceptibility to proteolytic degradation. In this regard, nanotechnologies represent an innovative strategy to circumvent these issues. According to the literature, a large variety of nanoparticulate systems have been employed for drug-delivery, bioimaging, biosensors or nanoantibiotics. The possibility of conjugating different types of molecules, including AMPs, to these systems, allows the production of nanoformulations able to enhance the biological profile of the compound while reducing its cytotoxicity and prolonging its residence time. In this minireview, inorganic gold nanoparticles (NPs) and biodegradable polymeric NPs made of poly(lactide-coglycolide) are described with particular emphasis on examples of the conjugation of AMPs to them, to highlight the great potential of such nanoformulations as alternative antimicrobials.


2021 ◽  
pp. 1-16
Author(s):  
Anca Butiuc-Keul ◽  
Anca Farkas ◽  
Rahela Carpa ◽  
Dumitrana Iordache

Being frequently exposed to foreign nucleic acids, bacteria and archaea have developed an ingenious adaptive defense system, called CRISPR-Cas. The system is composed of the Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) array, together with CRISPR (<i>cas</i>)-associated genes. This system consists of a complex machinery that integrates fragments of foreign nucleic acids from viruses and mobile genetic elements (MGEs), into CRISPR arrays. The inserted segments (spacers) are transcribed and then used by cas proteins as guide RNAs for recognition and inactivation of the targets. Different types and families of CRISPR-Cas systems consist of distinct adaptation and effector modules with evolutionary trajectories, partially independent. The origin of the effector modules and the mechanism of spacer integration/deletion is far less clear. A review of the most recent data regarding the structure, ecology, and evolution of CRISPR-Cas systems and their role in the modulation of accessory genomes in prokaryotes is proposed in this article. The CRISPR-Cas system&apos;s impact on the physiology and ecology of prokaryotes, modulation of horizontal gene transfer events, is also discussed here. This system gained popularity after it was proposed as a tool for plant and animal embryo editing, in cancer therapy, as antimicrobial against pathogenic bacteria, and even for combating the novel coronavirus – SARS-CoV-2; thus, the newest and promising applications are reviewed as well.


2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Nattaphop Noothuan ◽  
Kantamas Apitanyasai ◽  
Somsak Panha ◽  
Anchalee Tassanakajon

Abstract Objective Snails secrete different types of mucus that serve several functions, and are increasingly being exploited for medical and cosmetic applications. In this study, we explored the protein pattern and compared the biological properties of the mucus secreted from the mantle collar and foot of two snail species, Lissachatina fulica and Hemiplecta distincta. Result Protein profile showed a different pattern between the two species and between the two secretory parts. The mantle-specific protein bands were further characterized and among them was an antibacterial protein, achacin. Accordingly, the mucus from the mantle exhibited the higher antibacterial activity than that from the foot in both snail species. The mucus from H. distincta, first reported here, also showed antibacterial properties, but with a lower activity compared to that for L. fulica. Snail mucus also exhibited anti-tyrosinase activity and antioxidant activity but with no significant difference between the foot and mantle mucus. These results indicate some different protein compositions and biological activities of snail slime from the mantle and foot, which might be associated with their specific functions in the animal and are useful for medical applications.


Planta Medica ◽  
2021 ◽  
Author(s):  
Jerald J. Nair ◽  
Johannes van Staden

AbstractOver 600 alkaloids have to date been identified in the plant family Amaryllidaceae. These have been arranged into as many as 15 different groups based on their characteristic structural features. The vast majority of studies on the biological properties of Amaryllidaceae alkaloids have probed their anticancer potential. While most efforts have focused on the major alkaloid groups, the volume and diversity afforded by the minor alkaloid groups have promoted their usefulness as targets for cancer cell line screening purposes. This survey is an in-depth review of such activities described for around 90 representatives from 10 minor alkaloid groups of the Amaryllidaceae. These have been evaluated against over 60 cell lines categorized into 18 different types of cancer. The montanine and cripowellin groups were identified as the most potent, with some in the latter demonstrating low nanomolar level antiproliferative activities. Despite their challenging molecular architectures, the minor alkaloid groups have allowed for facile adjustments to be made to their structures, thereby altering the size, geometry, and electronics of the targets available for structure-activity relationship studies. Nevertheless, it was seen with a regular frequency that the parent alkaloids were better cytotoxic agents than the corresponding semisynthetic derivatives. There has also been significant interest in how the minor alkaloid groups manifest their effects in cancer cells. Among the various targets and pathways in which they were seen to mediate, their ability to induce apoptosis in cancer cells is most appealing.


2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Tina Briolay ◽  
Tacien Petithomme ◽  
Morgane Fouet ◽  
Nelly Nguyen-Pham ◽  
Christophe Blanquart ◽  
...  

Abstract Background As a complement to the clinical development of new anticancer molecules, innovations in therapeutic vectorization aim at solving issues related to tumor specificity and associated toxicities. Nanomedicine is a rapidly evolving field that offers various solutions to increase clinical efficacy and safety. Main Here are presented the recent advances for different types of nanovectors of chemical and biological nature, to identify the best suited for translational research projects. These nanovectors include different types of chemically engineered nanoparticles that now come in many different flavors of ‘smart’ drug delivery systems. Alternatives with enhanced biocompatibility and a better adaptability to new types of therapeutic molecules are the cell-derived extracellular vesicles and micro-organism-derived oncolytic viruses, virus-like particles and bacterial minicells. In the first part of the review, we describe their main physical, chemical and biological properties and their potential for personalized modifications. The second part focuses on presenting the recent literature on the use of the different families of nanovectors to deliver anticancer molecules for chemotherapy, radiotherapy, nucleic acid-based therapy, modulation of the tumor microenvironment and immunotherapy. Conclusion This review will help the readers to better appreciate the complexity of available nanovectors and to identify the most fitting “type” for efficient and specific delivery of diverse anticancer therapies.


Nanoscale ◽  
2015 ◽  
Vol 7 (48) ◽  
pp. 20460-20473 ◽  
Author(s):  
Tianshu Wu ◽  
Keyu He ◽  
Qinglin Zhan ◽  
Shengjun Ang ◽  
Jiali Ying ◽  
...  

As quantum dots (QDs) are widely used in biomedical applications, the number of studies focusing on their biological properties is increasing.


RSC Advances ◽  
2015 ◽  
Vol 5 (12) ◽  
pp. 8680-8687 ◽  
Author(s):  
P. Mostafalu ◽  
S. Sonkusale

Different types of nanowires made from platinum, nickel and copper are fabricated and patterned with microscale resolution on paper substrates and employed for biomedical applications.


Author(s):  
Weibing Teng ◽  
Joseph Cappello ◽  
Xiaoyi Wu

Genetic engineering of protein-based materials provides material scientists with high levels of control in material microstructures, properties, and functions [1]. For example, multi-block protein copolymers in which individual block may possess distinct mechanical or biological properties have been biosynthesized [2, 3]. Polypeptide sequences derived from well-studied structural proteins (e.g., collagen, silk, elastin) are often used as motifs in the design and synthesis of new protein-based material, in which new functional groups may be incorporated. In this fashion, we have produced a series of silk-elastin-like proteins (SELPs) consisting of polypeptide sequences derived from silk of superior mechanical strength and elastin that is extremely durable and resilient [2, 4]. Notably, the silk-like blocks are capable of crystallizing to form virtual cross-links between elastin-mimetic sequences, which, in turn, lower the crystallinity of the silk-like blocks and thus enhance the solubility of SELPs. Consequently, SELPs may be fabricated into useful structures for biomedical applications, including drug delivery. In this study, we will characterize viscoelastic properties of SELPs, which are particularly relevant to tissue engineering applications.


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