Lung cancer (LC) and chronic obstructive pulmonary disease (COPD) are among the leading causes of mortality worldwide. Cigarette smoking is among the main aetiologic factors for both ailments. These diseases share common pathogenetic mechanisms including inflammation, oxidative stress, and tissue remodelling. Current therapeutic approaches are limited by low efficacy and adverse effects. Consequentially, LC has a 5-year survival of < 20%, while COPD is incurable, underlining the necessity for innovative treatment strategies. Two promising emerging classes of therapy against these diseases include plant-derived molecules (phytoceuticals) and nucleic acid-based therapies. The clinical application of both is limited by issues including poor solubility, poor permeability, and, in the case of nucleic acids, susceptibility to enzymatic degradation, large size, and electrostatic charge density. Nanoparticle-based advanced drug delivery systems are currently being explored as flexible systems allowing to overcome these limitations. In this review, an updated summary of the most recent studies using nanoparticle-based advanced drug delivery systems to improve the delivery of nucleic acids and phytoceuticals for the treatment of LC and COPD is provided. This review highlights the enormous relevance of these delivery systems as tools that are set to facilitate the clinical application of novel categories of therapeutics with poor pharmacokinetic properties.
Matched MeSH terms: Nucleic Acids/administration & dosage; Nucleic Acids/therapeutic use
An abdominal aortic aneurysm (AAA) is abnormal swelling in the abdominal aorta and a prevalent life-threatening disease. This research introduces a new interdigitated microelectrode (IDME)-sensing surface modified by iron oxide nanoworms (IONWs) for detecting the AAA biomarker insulin-like growth factor-1 (IGF1). A sandwich pattern was formulated with the IGF1 aptamer and IGFBP1 (IGF binding protein-1) on the IONW-constructed IDME hybrid to identify IGF1. The surface morphology of the IONWs revealed a uniform distribution of worm-like structures (80-100 nm) as confirmed by FESEM and FETEM analyses. Further, the presence of the major elements, Fe and O, was confirmed by EDX and XPS studies. The crystal planes that appeared in the IONW reflect cubic magnetite. IONW-modified IDME attained a limit of detection for IGF1 of 1 fM (3σ) with an aptamer-IGF1-IGFBP1 sandwich. This sandwich with IGFBP1 enhanced the current level at all concentrations of IGF1 and displayed linearity in the range 1 fM to 100 pM with a determination coefficient of R2 = 0.9373 [y = 3.38221x - 4.79]. Control experiments with complementary aptamer sequences, IGF2 and IGFBP3 did not show notable signal changes, indicating the specific detection of IGF1. This IONW constructed electrode helps to achieve the detection of low amounts of IGF1 and diagnose AAA at the stage prior to rupture.
Madagascar periwinkle, Catharanthus roseus (L.) G. Don, is a member of the Apocynaceae plant family that is native to Madagascar and produces dimeric terpenoid indole alkaloids that are used in the treatment of hypertension and cancer. Periwinkle as an indicator plant is highly susceptible to phytoplasmas and spiroplasma infection from different crops, and has been found to be naturally infected with spiroplasmas in Arizona, California, and the Mediterranean countries. In this study, surveys of suspected diseased periwinkles were conducted in various regions of Selangor State, Malaysia. Periwinkles showing rapid decline in the number and size of the flowers, premature abscission of buds and flowers, reduction in leaf size, chlorosis of the leaf tips and margins, general chlorosis, and stunting and dying plants were collected. These symptoms were widespread on periwinkle in this state. Diagnosis of the disease was based on symptomatology, grafting, serology (ELISA), PCR techniques, and cultivation. Tests for transmission by grafting were conducted using symptomatic periwinkle plants. Symptoms were induced on all eight graft-inoculated healthy periwinkles approximately 2 weeks after side grafting. Preliminary examination was performed by ELISA with Spiroplasma citri Saglio polyclonal antibody that was prepared against an Iranian S. citri isolate (H. Rahimian, unpublished data). Leaf extracts of all 24 symptomatic periwinkles gave positive ELISA reactions at OD405 readings ranging from 0.310 to 0.654 to the antibody against S. citri by the indirect ELISA method. Six healthy periwinkle leaves gave OD405 readings around 0.128. Total nucleic acids were extracted from 10 symptomatic and 5 asymptomatic plants (4). PCR using the ScR16F1/ScR16R1 primer pair designed to detect S. citri in carrot and P1/P7 and secA for1/rev3 primer pairs designed for identification of phytoplasmas were used to detect the causal agent (1-3). Amplification failed when the P1/P7 universal phytoplasma primer pair was used for diseased samples. However, the PCR assays resulted in products of 1,833 and 800 bp with ScR16F1/ScR16R1 and secA for1/rev3, respectively. Five of each ScR16F1/ScR16R1 and SecAfor1/SecArev3 products were cloned with the Topo TA cloning kit (Invitrogen, Carlsbad, CA), sequenced, and deposited as GenBank Accession Nos. HM015669 and FJ011099, respectively. Sequences for both genes indicated that S. citri was associated with the disease on periwinkle. ScR16F1/ScR16R1 products cloned from symptomatic periwinkles had 98% sequence identity with S. citri (GenBank Accession No. AM285316), while nucleotide sequences of SecAfor1/SecArev3 products had 88% sequence identity with S. citri GII3-3X (GenBank Accession No. AM285304). S. citri was cultivated from 10 S. citri-infected periwinkles using filtration and SP-4 media. Twenty culture tubes started to change culture medium color from red to yellow 1 month after cultivation. Helical and motile S. citri was observed in the dark-field microscope. To our knowledge, this is the first report on the presence and occurrence of S. citri in Southeast Asia and its association with lethal yellows on periwinkle in Malaysia. References: (1) J. Hodgetts et al. Int. J. Syst. Evol. Microbiol. 58:1826, 2008. (2) I.-M. Lee et al. Phytopathology 85:728, 1995. (3) I.-M. Lee et al. Plant Dis. 90:989, 2006. (4) Y.-P. Zhang et al. J. Virol. Methods. 71:45, 1998.
Aptamers are a class of folded nucleic acid strands capable of binding to different target molecules with high affinity and selectivity. Over the years, they have gained a substantial amount of interest as promising molecular tools for numerous medical applications, particularly in targeted therapeutics. However, only the different treatment approaches and current developments of aptamer-drug therapies have been discussed so far, ignoring the crucial technical and functional aspects of constructing a therapeutically effective aptamer-driven drug delivery system that translates to improved in-vivo performance. Hence, this paper provides a comprehensive review of the strategies used to improve the therapeutic performance of aptamer-guided delivery systems. We focus on the different functional features such as drug deployment, payload capacity, in-vivo stability and targeting efficiency to further our knowledge in enhancing the cell-specific delivery of aptamer-drug conjugates. Each reported strategy is critically discussed to emphasize both the benefits provided in comparison with other similar techniques and to outline their potential drawbacks with respect to the molecular properties of the aptamers, the drug and the system to be designed. The molecular architecture and design considerations for an efficient aptamer-based delivery system are also briefly elaborated.
Genetic intervention via the delivery of functional genes such as plasmid DNA (pDNA) and short-interfering RNA (siRNA) offers a great way to treat many single or multiple genetic defects effectively, including mammary carcinoma. Delivery of naked therapeutic genes or siRNAs is, however, short-lived due to biological clearance by scavenging nucleases and circulating monocytes. Low cellular internalization of negatively-charged nucleic acids further causes low transfection or silencing activity. Development of safe and effectual gene vectors is therefore undeniably crucial to the success of nucleic acid delivery. Inorganic nanoparticles have attracted considerable attention in the recent years due to their high loading capacity and encapsulation activity. Here we introduce strontium salt-based nanoparticles, namely, strontium sulfate, strontium sulfite and strontium fluoride as new inorganic nanocarriers. Generated strontium salt particles were found to be nanosized with high affinity towards negatively-charged pDNA and siRNA. Degradation of the particles was seen with a drop in pH, suggesting their capacity to respond to pH change and undergo dissolution at endosomal pH to release the genetic materials. While the particles are relatively nontoxic towards the cells, siRNA-loaded SrF2 and SrSO3 particles exerted superior transgene expression and knockdown activity of MAPK and AKT, leading to inhibition of their phosphorylation to a distinctive extent in both MCF-7 and 4T1 cells. Strontium salt nanoparticles have thus emerged as a promising tool for applications in cancer gene therapy.
In this study, we report for the first time the development of a dry-reagent-based nucleic acid-sensing platform by combining a thermostabilised linear-after-the-exponential (LATE)-PCR assay with a one-step, hybridisation-based nucleic acid lateral flow biosensor. The nucleic acid-sensing platform was designed to overcome the need for stringent temperature control during transportation or storage of reagents and reduces the dependency on skilled personnel by decreasing the overall assay complexity and hands-on time. The platform was developed using toxigenic Vibrio cholerae as the model organism due to the bacterium's propensity to cause epidemic and pandemic cholera. The biosensor generates result which can be visualised with the naked eyes and the limit of detection was found to be 1pg of pure genomic DNA and 10CFU/ml of toxigenic V. cholerae. The dry-reagent-based nucleic acid-sensing platform was challenged with 95 toxigenic V. cholerae, 7 non-toxigenic V. cholerae and 66 other bacterial strains in spiked stool sample and complete agreement was observed when the results were compared to that of monosialoganglioside (GM1)-ELISA. Heat-stability of the thermostabilised LATE-PCR reaction mixes at different storage temperatures (4-56°C) was investigated for up to 90days. The dry-reagent-based genosensing platform with ready-to-use assay components provides an alternative method for sequence-specific detection of nucleic acid without any cold chain restriction that is associated with conventional molecular amplification techniques.
In this work, a simple and inexpensive physical lysis method using a cordless drill fitted with a plastic pellet pestle and 150 mg of sterile sea sand was established for the extraction of DNA from six strains of freshwater microalgae. This lysis method was also tested for RNA extraction from two microalgal strains. Lysis duration between 15 and 120 s using the cetyltrimethyl ammonium bromide (CTAB) buffer significantly increased the yield of DNA from four microalgalstrains (Monoraphidium griffithii NS16, Scenedesmus sp. NS6, Scenedesmus sp. DPBC1 and Acutodesmus sp. DPBB10) compared to control. It was also found that grinding was not required to obtain DNA from two strains of microalgae (Choricystis sp. NPA14 and Chlamydomonas sp. BM3). The average DNA yield obtained using this lysis method was between 62.5 and 78.9 ng/mg for M. griffithii NS16, 42.2-247.0 ng/mg for Scenedesmus sp. NS6, 70.2-110.9 ng/mg for Scenedesmus sp. DPBC1 and 142.8-164.8 ng/mg for Acutodesmus sp. DPBB10. DNA obtained using this method was sufficiently pure for PCR amplification. Extraction of total RNA from M. griffithii NS16 and Mychonastes sp. NPD7 using this lysis method yielded high-quality RNA suitable for RT-PCR. This lysis method is simple, cheap and would enable rapid nucleic acid extraction from freshwater microalgae without requiring costly materials and equipment such as liquid nitrogen or beadbeaters, and would facilitate molecular studies on microalgae in general.
Cellulose and its forms are widely used in biomedical applications due to their biocompatibility, biodegradability and lack of cytotoxicity. It provides ample opportunities for the functionalization of supported magnetic nanohybrids (CSMNs). Because of the abundance of surface hydroxyl groups, they are surface tunable in either homogeneous or heterogeneous solvents and thus act as a substrate or template for the CSMNs' development. The present review emphasizes on the synthesis of various CSMNs, their physicomagnetic properties, and potential applications such as stimuli-responsive drug delivery systems, MRI, enzyme encapsulation, nucleic acid extraction, wound healing and tissue engineering. The impact of CSMNs on cytotoxicity, magnetic hyperthermia, and folate-conjugates is highlighted in particular, based on their structures, cell viability, and stability. Finally, the review also discussed the challenges and prospects of CSMNs' development. This review is expected to provide CSMNs' development roadmap in the context of 21st-century demands for biomedical therapeutics.
Current immunological issues in bone grafting regarding the transfer of xenogeneic donor bone cells into the recipient are challenging the industry to produce safer acellular natural matrices for bone regeneration. The aim of this study was to investigate the efficacy of a novel decellularization technique for producing bovine cancellous bone scaffold and compare its physicochemical, mechanical, and biological characteristics with demineralized cancellous bone scaffold in an in-vitro study. Cancellous bone blocks were harvested from a bovine femoral head (18-24 months old) subjected to physical cleansing and chemical defatting, and further processed in two ways. Group I was subjected to demineralization, while Group II underwent decellularization through physical, chemical, and enzymatic treatments. Both were then freeze-dried, and gamma radiated, finally producing a demineralized bovine cancellous bone (DMB) scaffold and decellularized bovine cancellous bone (DCC) scaffold. Both DMB and DCC scaffolds were subjected to histological evaluation, scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/EDS), fourier-transform infrared spectroscopy (FTIR), quantification of lipid, collagen, and residual nucleic acid content, and mechanical testing. The osteogenic potential was investigated through the recellularization of scaffolds with human osteoblast cell seeding and examined for cell attachment, proliferation, and mineralization by Alizarin staining and gene expression. DCC produced a complete acellular extracellular matrix (ECM) with the absence of nucleic acid content, wider pores with extensive interconnectivity and partially retaining collagen fibrils. DCC demonstrated a higher cell proliferation rate, upregulation of osteogenic differentiation markers, and substantial mineralized nodules production. Our findings suggest that the decellularization technique produced an acellular DCC scaffold with minimal damage to ECM and possesses osteogenic potential through the mechanisms of osteoconduction, osteoinduction, and osteogenesis in-vitro.
The coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) began as a cluster of pneumonia cases in Wuhan, China before spreading to over 200 countries and territories on six continents in less than six months. Despite rigorous global containment and quarantine efforts to limit the transmission of the virus, COVID-19 cases and deaths have continued to increase, leaving devastating impacts on the lives of many with far-reaching effects on the global society, economy and healthcare system. With over 43 million cases and 1.1 million deaths recorded worldwide, accurate and rapid diagnosis continues to be a cornerstone of pandemic control. In this review, we aim to present an objective overview of the latest nucleic acid-based diagnostic tests for the detection of SARS-CoV-2 that have been authorized by the Food and Drug Administration (FDA) under emergency use authorization (EUA) as of 31 October 2020. We systematically summarize and compare the principles, technologies, protocols and performance characteristics of amplification- and sequencing-based tests that have become alternatives to the CDC 2019-nCoV Real-Time RT-PCR Diagnostic Panel. We highlight the notable features of the tests including authorized settings, along with the advantages and disadvantages of the tests. We conclude with a brief discussion on the current challenges and future perspectives of COVID-19 diagnostics.
A novel electrochemical DNA biosensor for ultrasensitive and selective quantitation of Escherichia coli DNA based on aminated hollow silica spheres (HSiSs) has been successfully developed. The HSiSs were synthesized with facile sonication and heating techniques. The HSiSs have an inner and an outer surface for DNA immobilization sites after they have been functionalized with 3-aminopropyltriethoxysilane. From field emission scanning electron microscopy images, the presence of pores was confirmed in the functionalized HSiSs. Furthermore, Brunauer-Emmett-Teller (BET) analysis indicated that the HSiSs have four times more surface area than silica spheres that have no pores. These aminated HSiSs were deposited onto a screen-printed carbon paste electrode containing a layer of gold nanoparticles (AuNPs) to form a AuNP/HSiS hybrid sensor membrane matrix. Aminated DNA probes were grafted onto the AuNP/HSiS-modified screen-printed electrode via imine covalent bonds with use of glutaraldehyde cross-linker. The DNA hybridization reaction was studied by differential pulse voltammetry using an anthraquinone redox intercalator as the electroactive DNA hybridization label. The DNA biosensor demonstrated a linear response over a wide target sequence concentration range of 1.0×10-12-1.0×10-2 μM, with a low detection limit of 8.17×10-14 μM (R2 = 0.99). The improved performance of the DNA biosensor appeared to be due to the hollow structure and rough surface morphology of the hollow silica particles, which greatly increased the total binding surface area for high DNA loading capacity. The HSiSs also facilitated molecule diffusion through the silica hollow structure, and substantially improved the overall DNA hybridization assay. Graphical abstract Step-by-step DNA biosensor fabrication based on aminated hollow silica spheres.
A rapid, simple, sensitive, and selective point-of-care diagnosis tool kit is vital for detecting the coronavirus disease (COVID-19) based on the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) strain. Currently, the reverse transcriptase-polymerase chain reaction (RT-PCR) is the best technique to detect the disease. Although a good sensitivity has been observed in RT-PCR, the isolation and screening process for high sample volume is limited due to the time-consuming and laborious work. This study introduced a nucleic acid-based surface-enhanced Raman scattering (SERS) sensor to detect the nucleocapsid gene (N-gene) of SARS-CoV-2. The Raman scattering signal was amplified using gold nanoparticles (AuNPs) possessing a rod-like morphology to improve the SERS effect, which was approximately 12-15 nm in diameter and 40-50 nm in length. These nanoparticles were functionalised with the single-stranded deoxyribonucleic acid (ssDNA) complemented with the N-gene. Furthermore, the study demonstrates method selectivity by strategically testing the same virus genome at different locations. This focused approach showcases the method's capability to discern specific genetic variations, ensuring accuracy in viral detection. A multivariate statistical analysis technique was then applied to analyse the raw SERS spectra data using the principal component analysis (PCA). An acceptable variance amount was demonstrated by the overall variance (82.4 %) for PC1 and PC2, which exceeded the desired value of 80 %. These results successfully revealed the hidden information in the raw SERS spectra data. The outcome suggested a more significant thymine base detection than other nitrogenous bases at wavenumbers 613, 779, 1219, 1345, and 1382 cm-1. Adenine was also less observed at 734 cm-1, and ssDNA-RNA hybridisations were presented in the ketone with amino base SERS bands in 1746, 1815, 1871, and 1971 cm-1 of the fingerprint. Overall, the N-gene could be detected as low as 0.1 nM within 10 mins of incubation time. This approach could be developed as an alternative point-of-care diagnosis tool kit to detect and monitor the COVID-19 disease.