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Crystallization, formation, and accumulation of defects and mesopores in the ZSM-5 zeolite samples, which are synthesized from the gel composition of 1.2Na2O 0.1Al2O3 0.8 tetra-propylammonium hydroxide (TPAOH) 6SiO2 400H2O at a temperature of 140 degree Celsius (°C) in 10, 15, and 18 h, are studied by using the Positron annihilation lifetime (PALS) and X-ray diffraction (XRD) spectroscopies. The XRD is used for investigating the crystalline concentration and nano-crystal size of ZSM-5 during the crystallizing process, whereas the PALS is performed in order to determine the presence of templates, defects, and mesopores in the zeolite samples. The latter are calcined in air during 1, 2, and 3 h at a temperature of 600 °C before being measured. The results obtained indicate that there exist clusters of small crystals in the early crystalline stages of the samples. The size of these crystals increases with time and reaches approximately 100 nm after 18 h of reaction. In addition, the template (TPAOH) is found to exist not only in the channels inside the framework but also in the mesopores outside it. Finally, by analyzing the Positron lifetime spectra, we have found for the first time the simultaneous existence of defects and mesopores, which are formatted and accumulated during the crystallization of ZSM-5. Those important results contribute significantly to our understanding of the internal structure of the synthetic zeolite ZSM-5 as well as the synthetic processes for producing zeolites with special features.

To serve health care, up to now, sciences have successfully developed many drugs with different effects. In general, in terms of chemical structure and effect characteristics, medicine can be classified into groups including inorganic drugs, small-molecule organic drugs, protein drugs (macromolecules), and recently a new group of drugs has been formed, separate from the protein drug class, which is the RNA drugs. In terms of pharmacological effects, in general, the mechanisms of protein drugs and small-molecule organic drugs do not differ too much because they all act at a particular stage related to pathological manifestations. Protein drugs in the process of development have gone through many different stages, with different origins, from extraction and isolation from living tissues at an early stage to biosynthesis by recombinant technology and other modern biotechnology methods. To date, most of the proteins used in medicine have been produced through recombinant pathways, possibly through different semisynthetic steps to give the molecules more superior drug properties. Therefore, the group of protein drugs has an additional new name, biopharmaceuticals, to indicate their synthetic origin by biological methods. The research, development, and application of protein drugs into clinical practice are of great significance, helping to enhance the ability of medicine to control and treat many difficult-to-treat diseases today, bringing many opportunities to have good health for people. Keywords: Protein drugs, RNA drugs, Biopharmaceuticals, Inorganic drugs, Small-molecule organic drugs, Drug development, Cytokine, Enzyme, Hormone peptide, Stem cell, Recombinant technology, Biosimilar. *  

RNA drugs are a new group of drugs that delivers RNAs or similar structures inside the body to achieve the therapeutic effect. This is a promising direction in drug development to treat serious and rare genetic diseases more specifically and effectively. In reality, the genetic systems and protein synthesis processes of living organisms are extremely complex, so the development of RNA drugs faces many difficulties. To achieve success, many different studies have been carried out to address issues such as finding suitable RNAs, synthesizing similar RNA structures, stabilizing RNA structures, and introducing drugs into targeted cells. Since the first RNA drug was officially approved by the FDA (2004), 10 RNA drugs in total have been approved to date. Among them, two vaccines, appearing at the time when much needed support to cope with the new SARS-CoV-2 variants, were developed using mRNA technology. With these achievements, scientists can have more confidence in the possibilities of evolving a new drug group that is more specific and effective, which is RNA drugs. This review briefly introduces the group of drugs that use RNAs, RNA structural analogs, and RNA biomarkers to develop novel drugs for application in the diagnosis, prevention, and treatment of disease. Keywords: RNA drugs; mRNA; the protein; vaccines; RNA diagnostics; small molecule drugs; RNA target. References [1] U. Sahin, K. Karikó, Ö. Türeci, Mrna-Based Therapeutics-Developing A New Class of Drugs, Nature Reviews Drug Discovery, Vol. 13, No. 10, 2014, pp. 759-780.[2] T. H. Nguyen, T. M. H. Pham, M. K. Tu, Pharmacogenetics: Prospects and Issues. Journal of Pharmacy, No. 54, Vol. 456, 2014, pp. 2-6.[3] A. M. Yu, Y. H. Choi, M. J. Tu, Rna Drugs and Rna Targets for Small Molecules: Principles, Progress, and Challenges, Pharmacological Reviews, Vol. 72, No. 4, 2020, pp. 862-898.[4] M. A. Hendaus, F. A. Jomha, Mrna Vaccines for Covid-19: A Simple Explanation, Qatar Medical Journal, Vol. 2021, No. 1, 2021, pp. 1-5.[5] A. Banerji, P. G. Wickner, R. Saff, C. A. Stone Jr, L. B. Robinson, A. A. Long et al., Mrna Vaccines to Prevent Covid-19 Disease and Reported Allergic Reactions: Current Evidence and Suggested Approach, the Journal of Allergy and Clinical Immunology: in Practice, Vol. 9, No. 4, 2021, pp. 1423-1437.[6] https://www.Fda.Gov/Emergency-Preparedness-and-Response/Coronavirus-Disease-2019-Covid-19/Covid-19-Vaccines (accessed on: December 15th, 2021).[7] E. H. Aarntzen, G. Schreibelt, K. Bol, W. J. Lesterhuis, A. J. Croockewit, J .H. De Wilt et al., Vaccination with Mrna-Electroporated Dendritic Cells Induces Robust Tumor Antigen-Specific Cd4+ and Cd8+ T Cells Responses in Stage Iii and Iv Melanoma Patients, Clinical Cancer Research, Vol. 18, No. 19, 2012, pp. 5460-5470.[8] H. M. Phan, K. L. Vu, T. H. Nguyen, T. T. Bui, A Comprehensive Review of Vaccines Against Covid-19, VNU Journal of Science: Medical and Pharmaceutical Sciences, Vol. 37, No. 3, 2021, pp. 1-19 (in Vietnamese).[9] N. Pardi, M. J. Hogan, F. W. Porter, D. Weissman, Mrna Vaccines - A New Era in Vaccinology, Nature Reviews Drug Discovery, Vol. 17, No. 4, 2018, pp. 261-279.[10] G. Wen, T. Zhou, W. Gu, The Potential of Using Blood Circular Rna As Liquid Biopsy Biomarker for Human Diseases. Protein & Cell, Vol. 12, No. 12, 2021, pp. 911-946.[11] S. Sabarimurugan, C. Kumarasamy, S. Baxi, A. Devi, R. Jayaraj, Systematic Review and Meta-Analysis of Prognostic Microrna Biomarkers for Survival Outcome in Nasopharyngeal Carcinoma. Plos One, Vol. 14, No. 2, 2019, pp. 1-18.[12] F. Wang, T. Zuroske, J. K. Watts, Rna Therapeutics on the Rise, Nat Rev Drug Discov, Vol. 19, No. 7, 2020, pp. 441-442.[13] E. J. Wild, S. J. Tabrizi, Therapies Targeting Dna and Rna in Huntington's Disease, The Lancet Neurology, Vol. 16, No. 10, 2017, pp. 837-847.[14] H. Han, Rna Interference to Knock Down Gene Expression, Disease Gene Identification, 2018, pp. 293-302.[15] J. Kim, C. Hu, C. M. E. Achkar, L.E. Black, J. Douville, A. Larson et al., Patient-Customized Oligonucleotide Therapy for A Rare Genetic Disease, New England Journal of Medicine, Vol. 381, No. 17, 2019, pp. 1644-1652.[16] U. Food, D. Administration, Fda Approves First-of-Its Kind Targeted Rna-Based Therapy to Treat A Rare Disease, Silver Spring (Md): Usfda, 2018.[17] E. Sardh, P. Harper, M. Balwani, P. Stein, D. Rees, D. M. Bissel et al., Phase 1 Trial of An Rna Interference Therapy for Acute Intermittent Porphyria, New England Journal of Medicine, Vol. 380, No. 6, 2019, pp. 549-558.[18] G. Devi, Sirna-Based Approaches in Cancer Therapy, Cancer Gene Therapy, Vol. 13, No. 9, 2006, pp. 819-829.[19] T. G. Hopkins, M. Mura, H. A. A. Ashtal, R. M. Lahr, N. A. Latip, K. Sweeney et al., The Rna-Binding Protein Larp1 Is A Post-Transcriptional Regulator of Survival and Tumorigenesis in Ovarian Cancer, Nucleic Acids Research, Vol. 44, No. 3, 2016, pp. 1227-1246.[20] V. Iadevaia, M. D. Wouters, A. Kanitz, A. M. M. González, E. E. Laing, A. P. Gerber, Tandem Rna Isolation Reveals Functional Rearrangement of Rna-Binding Proteins on Cdkn1b/P27 Kip1 3’utrs in Cisplatin Treated Cells, Rna Biology, Vol. 17, No. 1, 2020, pp. 33-46.[21] T. T. Bui, K. S. Phan, T. M. H. Pham, T. H. Nguyen, PEGylation of Curcumin and Prospect of Application, VNU Journal of Science: Medical and Pharmaceutical Sciences, Vol. 32, No. 1, 2016, pp 1-11.

The present paper proposes a novel model for estimating the free-volume size of the porous materials based on the analysis of the experimental ortho-positronium (o-Ps) lifetimes collecting within more than four decades. The model is derived by combining the semi-classical (SE) physics model, which works in the region of large pores (pore size R > 1 nm), with the conventional Tao-Eldrup (TE) model, which is applicable only for the small-pore region (R < 1 nm). Thus, the resulting model, called the hybrid (HYB) model, is able to smoothly connect the o-Ps lifetimes in the two regions of the pore. Moreover, by introducing the o-Ps diffusion probability parameter (D), the HYB model has reproduced quite well the experimental o-Ps lifetimes in the whole region of pore sizes. It is even in a better agreement with the experimental data than the most up-to-date rectangular TE (RTE) and Tokyo models. In particular, by adjusting the value of D, * Corresponding Author the HYB model can also describe very well the two defined sets of experimental o-Ps lifetime in the pores with spherical and channel geometries. The merit of the present model, in comparison with the previously proposed ones, is that it is applicable for the pore size in the universal range of 0.2 − 400 nm for most of porous materials with different geometries.

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Background: Amphotericin B (AmB) is a drug of choice in the therapy of systemic fungal infection because of its board-spectrum antifungal activity. However, its conventional formulation has many side effects such as acute and chronic nephrotoxicity. Liposomes have been developed to reduce the drug’s toxicity. However, they had to meet strict stability criteria. In general, liposomes can be freeze-dried to inhibit liposomes infusion, phospholipids degradation during storage. Liposomal size usually increases after freeze-drying because of being influenced by many factors in freezing, lyophilizing and rehydration processes. Therefore, cryoprotectants are used to stabilize liposomal vesicles during freeze-drying process. </P><P> Objective: In the present study, we developed AmB liposomal suspension and lyophilized liposomes loaded with AmB, evaluated the effect of different cryoprotectants on the characterization of freeze-dried AmB liposomes. </P><P> Methods: In this study, AmB liposomes were prepared from hydrogenated soy phosphatidylcholine, distearoylphosphatidylglycerol and cholesterol by thin lipid film hydration method using different hydrate mediums likely: Glucose solution, citrate buffer, phosphate buffer. High-pressure homogenization and extrusion methods were used to reducing vesicles size. Dynamic light scattering was used to characterize liposomal size, and size distribution. HPLC method was used to assay drug and determine entrapment efficiency. Liposomal suspension was lyophilized with different cryoprotectants: Sucrose, mannitol, lactose, trehalose and glycerol. Differential scanning calorimetry was used to study lyophilized cake. </P><P> Results: We found that liposomal suspension with hydration medium10 mM citrate buffer pH 5.5 had a small average size (<100nm) and narrow distribution (PDI <0.2). Sucrose and trehalose stabilized vesicles size during freezing process, and lyophilized liposomes with sucrose and trehalose had an elegant appearance, yellow, compact cake. DSC study showed that sucrose and trehalose in lyophilized cake were amorphous. The cake was rehydrated within 10 seconds to form liposomal suspension, in which vesicles size was less than 140 nm. </P><P> Conclusion: We have developed successfully AmB liposomal suspension and lyophilized liposomes loaded with AmB. Sucrose and trehalose can be used as cryoprotectants in the freeze-drying and reconstitution process.