DEVELOPING A MODEL OF LIPOSOMAL FORMULATION OF A NEW NATIONAL ANALOGUE HYPOTHALAMIC HORMONE SOMATOSTATIN, WHICH HAS ANTI-TUMOR ACTIVITY

2015 ◽  
Vol 14 (4) ◽  
pp. 73-78
Author(s):  
E. V. Sanarova ◽  
A. V. Lantsova ◽  
Xi Zhang ◽  
M. V. Dmitrieva ◽  
A. P. Polozkova ◽  
...  

At present, the hormone somatostatin analogues is increasing interest in connection with their activity against hormone-dependent tumors, which leads to the need to develop domestic drugs belonging to this group. In the laboratory of chemical synthesis Institute of experimental diagnostics and chemotherapy of FSBI «N.N. Blokhin RCRC» synthesized new domestic pentapeptide somatostatin analogue of hypothalamic hormone (AGGS). In preliminary studies of this substance demonstrated sufficiently high antitumor activity AGGS on transplanted solid tumors of mice. Due to the insolubility of the substance in the water as an alternative liposomal formulation proposed, allowing to increase the bioavailability of the drag due to the possibility of intravenous administration, increased therapeutic efficacy and reduce side effects, by improving the selectivity of action against tumor cells. During experiments on the development of the liposomal formulation AGGS pre-established model containing as essential components of the liposomal bilayer and egg lecithin PEG-2000-DSPE in a molar ratio 72/1 and as a ciyo- protectant - sucrose. In developing the technological parameters of the process of obtaining dosage form (LF) found that for an acceptable size derived phosphohpid vesicles needs about 7 cycles extrusion. The lack of stability of liposomal dispersion selected composition during storage has led to this problem by means of freeze-drying, which kept the physico-chemical parameters LF at the initial level. The efficacy of the model LF on transplantable tumors of mice - breast adenocarcinoma Ca-755, which was more than 60 % of ITG at a dose of 5 mg / kg and more than 80 % ITG with 20 mg / kg. The findings of biological experiments indicate the prospects for further research and improvement liposomal LF to produce high-performance domestic anticancer drag from the group of somatostatin analogues.

2016 ◽  
Vol 15 (4) ◽  
pp. 78-84
Author(s):  
E. V. Sanarova ◽  
Zhang Xi ◽  
M. V. Dmitrieva ◽  
A. V. Lantsova ◽  
O. L. Orlova ◽  
...  

Background. In connection with the prospect of the use of an analog of the hypothalamic hormone somatostatin synthesized by the laboratory of chemical synthesis Institute of experimental diagnostics and chemotherapy of FSBI «N.N. Blokhin Russian Cancer Research Center» and showed a high anti-tumor activity as a drug arises a need to establish an optimal technology of its receipt. In preliminary studies in a modelformulation for an analog of the hypothalamic hormone somatostatin selected liposome technological process of which has a series of specific steps comprising. Objective. Development of technology for obtaining liposomal formulation hypothalamic hormone somatostatin analogue. Materials and methods. Liposomes analog of the hypothalamic hormone somatostatin obtained by method Bengema in modification for hydrophobic substances. To reduce the diameter of the liposome are used methods extrusion, homogenization and ultrasonic. Analysis of the size of the liposomes was performed by correlation spectroscopy light scattering using nanosizer. The pH of the liposomal dispersion was determined by potentiometry. The quantitative content of the drug substance was determined by spectrophotometry using a standard sample with X (282 ± 3) nm and an alcoholic solution of empty liposomes as a reference solution. Amount of incorporated drug was calculated as the ratio of the concentration of drug in the liposome dispersion after filtration to the concentration of drug in the dispersion after preparation. Results and Conclusion. The hydrophobic nature of the substance causes an analog of the hypothalamic hormone somatostatin technological features of obtaining liposomal formulation. Since the step of forming a film of the lipid substance is dissolved in an organic solvent together with lipids, film is hydrated by a solution of cryoprotectant. Grinding liposomes an analog of the hypothalamic hormone somatostatin appropriate to be carried out using homogenization or extrusion methods, due to the high efficiency of these methods, the preservation stability of the liposomes and a high percentage of inclusion an analog of the hypothalamic hormone somatostatin, included in the liposomal bilayer. At the stage of separating the non-inclusion of substance an analog of the hypothalamic hormone somatostatin due to the insolubility of the substance in the water, you can use the filtering method, without the need for complicated procedures gel filtration, dialysis, etc. Furthermore the process of separating a substance not included can be combined with the sterilization of the liposome dispersion by selecting a particular filter material.


1986 ◽  
Vol 113 (1) ◽  
pp. 42-46 ◽  
Author(s):  
Gareth Williams ◽  
Marius Kraenzlin ◽  
Laurence Sandier ◽  
Jacky Burrin ◽  
Adam Law ◽  
...  

Abstract. Inappropriate hypersecretion of TSH was investigated in a 25 year old man whose hyperthyroidism had relapsed 4 years after subtotal thyroidectomy. Serum TSH levels were further increased by both TRH and metoclopramide and were partially suppressed by triiodothyronine (120 μ/day). The serum α-subunit: TSH molar ratio was < 1.0, and computerised axial tomography showed no evidence of a pituitary tumour. These features are characteristic of inappropriate TSH secretion due to thyrotroph resistance to thyroid hormones. A long-acting somatostatin analogue (SMS 201-995), 50 μg injected sc twice-daily for three days, suppressed TSH levels and nearly normalised thyroid hormone levels. Somatostatin analogues may be therapeutically useful in thyrotoxicosis due to non-tumoural inappropriate TSH hypersecretion.


2018 ◽  
Vol 935 (5) ◽  
pp. 54-63
Author(s):  
A.A. Maiorov ◽  
A.V. Materuhin ◽  
I.N. Kondaurov

Geoinformation technologies are now becoming “end-to-end” technologies of the new digital economy. There is a need for solutions for efficient processing of spatial and spatio-temporal data that could be applied in various sectors of this new economy. Such solutions are necessary, for example, for cyberphysical systems. Essential components of cyberphysical systems are high-performance and easy-scalable data acquisition systems based on smart geosensor networks. This article discusses the problem of choosing a software environment for this kind of systems, provides a review and a comparative analysis of various open source software environments designed for large spatial data and spatial-temporal data streams processing in computer clusters. It is shown that the software framework STARK can be used to process spatial-temporal data streams in spatial-temporal data streams. An extension of the STARK class system based on the type system for spatial-temporal data streams developed by one of the authors of this article is proposed. The models and data representations obtained as a result of the proposed expansion can be used not only for processing spatial-temporal data streams in data acquisition systems based on smart geosensor networks, but also for processing spatial-temporal data streams in various purposes geoinformation systems that use processing data in computer clusters.


Materials ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4304
Author(s):  
Markssuel Teixeira Marvila ◽  
Afonso Rangel Garcez de de Azevedo ◽  
Paulo R. de de Matos ◽  
Sergio Neves Monteiro ◽  
Carlos Maurício Fontes Vieira

This review article proposes the identification and basic concepts of materials that might be used for the production of high-performance concrete (HPC) and ultra-high-performance concrete (UHPC). Although other reviews have addressed this topic, the present work differs by presenting relevant aspects on possible materials applied in the production of HPC and UHPC. The main innovation of this review article is to identify the perspectives for new materials that can be considered in the production of novel special concretes. After consulting different bibliographic databases, some information related to ordinary Portland cement (OPC), mineral additions, aggregates, and chemical additives used for the production of HPC and UHPC were highlighted. Relevant information on the application of synthetic and natural fibers is also highlighted in association with a cement matrix of HPC and UHPC, forming composites with properties superior to conventional concrete used in civil construction. The article also presents some relevant characteristics for the application of HPC and UHPC produced with alkali-activated cement, an alternative binder to OPC produced through the reaction between two essential components: precursors and activators. Some information about the main types of precursors, subdivided into materials rich in aluminosilicates and rich in calcium, were also highlighted. Finally, suggestions for future work related to the application of HPC and UHPC are highlighted, guiding future research on this topic.


2011 ◽  
Vol 217-218 ◽  
pp. 1606-1610
Author(s):  
Dong Jiang ◽  
Xiao Ran Zhang ◽  
Yan Mei Ma ◽  
Cheng You Ma

A series of random polysulfone/polyethersulfone (PSF/PES) copolymers were synthesized by the polycondensation of 4, 4'-isopropylidendiphenol, 4, 4΄-dihyolroxy diphenyl sulfone and 4, 4'-dichlorodiphenyl sulfone in the presence of K2CO3. We obtained a series of copolymers by changing the molar ratio of 4, 4΄-dihyolroxy diphenyl sulfone and 4, 4'-isopropylidendiphenol (it was marked as the ratio of S:A). The copolymers have the similar solubility with polyethersulfone. They also have high glass transition temperatures (Tg: 199°C~229°C) and 5% weight loss temperatures (4, 4'-isopropylidendiphenol: 4, 4΄-dihyolroxy diphenyl sulfone=1:1, Td5=497°C). At the same time the elongation at break is much higher than that of PES, while the tensile strength is a little lower than that of PES.


Author(s):  
Arpita Patel ◽  
Rahul Dhande ◽  
Hetal Thakkar

Abstract Objectives This project aimed at the formulation of dual drug entrapped liposomes held as freeze-dried intravaginal rod insert (IVR), to be administered by vaginal route for uterine targeting. Methods Liposomes were formulated by dehydration–rehydration method using 3 : 1 molar ratio of1,2-distearoyl-sn-glycero-3-phosphocholine : Cholesterol. Characterization was done for vesicle size, zeta potential, entrapment efficiency, surface morphology and % loading. Key findings Spherical and discrete vesicles of size 354 nm were observed in transmission electron microscopy (TEM) image. The entrapment efficiency of 90.91% and 74.3% w/w was obtained for Raloxifene Hydrochloride (RLX) and Leuprolide acetate (LA) respectively. Drug release was sustained for 6 days. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay results showed that dual drug entrapped liposomal formulation show significant cytotoxicity, as also confirmed by higher apoptosis in cell cycle analysis and apoptosis studies (FACS) analysis. Pharmacodynamic studies in New Zealand white female rabbits revealed that intravaginal administration of RLX-LA entrapped liposomal formulation shows considerable fibroid regression. Conclusions Uterine targeting of liposomal RLX-LA suggests its potential to solve the limitations of the presently available therapeutic options.


2015 ◽  
Vol 88 (3) ◽  
pp. 310-313 ◽  
Author(s):  
Ana Valea ◽  
Cristina Ghervan ◽  
Mara Carsote ◽  
Andra Morar ◽  
Iulia Iacob ◽  
...  

 Background and aims. Acromegaly is a complex endocrine disorder caused by excessive secretion of GH, secondary to a GH secreting pituitary adenoma or a mixed pituitary adenoma secreting GH and PRL.Methods. The aim of this study was to evaluate the effects of combination therapy: dopamine agonist and somatostatin analogue on GH and IGF1 levels in a group of 30 patients with acromegaly. Cabergoline in a dose of 2 mg/week and 4 mg/week respectively was associated with Sandostatin LAR in a dose of 20 mg/month and 30 mg/months respectively. Eight patients were treated with Lanreotide 30 mg/week and Cabergoline 2 mg/week and 3 patients were treated with Bromocriptine 10 mg/day and Sandostatin LAR 30 mg/month.Results. Combination therapy: Cabergoline and Sandostatin achieved normal levels of IGF1  in 32% of the patients, better results being obtained after 12 months of treatment in the group treated with 4 mg Cabergoline/week. In 37% of cases the levels of IGF1 decreased by 50% after 12 months of treatment. In the group treated with Cabergoline and Somatuline a normal level of IGF1 was achieved in 25% of patients after 12 months of treatment. The outcome for the group treated with Sandostatin and Bromocriptine was similar to that obtained under Cabergoline 2 mg/week. There was no significant correlation between the level of GH and the type or dose of dopamine agonist used.Conclusions. In conclusion, combination therapy consisting of dopamine agonist and somatostatin analogue achieves a significant reduction of IGF1 levels in patients with mixed adenomas secreting GH and PRL. A decrease in IGF1 levels is directly correlated with the dose of Cabergoline used. 


2013 ◽  
Vol 154 (39) ◽  
pp. 1535-1540 ◽  
Author(s):  
László Herszényi ◽  
Emese Mihály ◽  
Zsolt Tulassay

The effect of somatostatin on the gastrointestinal tract is complex; it inhibits the release of gastrointestinal hormones, the exocrine function of the stomach, pancreas and bile, decreases motility and influences absorption as well. Based on these diverse effects there was an increased expectation towards the success of somatostatin therapy in various gastrointestinal disorders. The preconditions for somatostatin treatment was created by the development of long acting somatostatin analogues (octreotide, lanreotide). During the last twenty-five years large trials clarified the role of somatostatin analogues in the treatment of various gastrointestinal diseases. This study summarizes shortly these results. Somatostatin analogue treatment could be effective in various pathological conditions of the gastrointestinal tract, however, this therapeutic modality became a part of the clinical routine only in neuroendocrine tumours and adjuvant treatment of oesophageal variceal bleeding and pancreatic fistulas. Orv. Hetil., 2013, 154, 1535–1540.


Author(s):  
Xiaoyu Wang ◽  
Tinghao Jia ◽  
Lun Pan ◽  
Qing Liu ◽  
Yunming Fang ◽  
...  

AbstractThe development of advanced air transportation has raised new demands for high-performance liquid hydrocarbon fuels. However, the measurement of fuel properties is time-consuming, cost-intensive, and limited to the operating conditions. The physicochemical properties of aerospace fuels are directly influenced by chemical composition. Thus, a thorough investigation should be conducted on the inherent relationship between fuel properties and composition for the design and synthesis of high-grade fuels and the prediction of fuel properties in the future. This work summarized the effects of fuel composition and hydrocarbon molecular structure on the fuel physicochemical properties, including density, net heat of combustion (NHOC), low-temperature fluidity (viscosity and freezing point), flash point, and thermal-oxidative stability. Several correlations and predictions of fuel properties from chemical composition were reviewed. Additionally, we correlated the fuel properties with hydrogen/carbon molar ratios (nH/C) and molecular weight (M). The results from the least-square method implicate that the coupling of H/C molar ratio and M is suitable for the estimation of density, NHOC, viscosity and effectiveness for the design, manufacture, and evaluation of aviation hydrocarbon fuels.


Polymers ◽  
2019 ◽  
Vol 11 (12) ◽  
pp. 1972 ◽  
Author(s):  
Heng Yue ◽  
Qianqian Xu ◽  
Xianheng Li ◽  
Jeevithan Elango ◽  
Wenhui Wu ◽  
...  

To investigate the structure and immunomodulatory activity of polysaccharide from Solanum muricatum, a novel acid polysaccharide named SMP-3a was purified from Solanum muricatum pulp through DEAE-52 cellulose column and Sephadex G-200 chromatography. Monosaccharide composition analysis showed that SMP-3a was mainly composed of rhamnose, arabinose, galactose, and galacturonic acid with the molar ratio of 1.09:2.64:1.54:1. The average molecular weight was found to be 227 kDa by high performance gel permeation chromatography (HPGPC). Thermal studies revealed the SMP-3a was a thermally stable polymer. Based on the results of methylation and NMR analysis, the backbone chain of SMP-3a was composed of →2)-α-l-Rhap-(1→, →4)-α-d-GalpA-(1→ and →4)-α-d-Galp-(1→. The side chain was consisted of α-l-Araf-(1→ and →5)-α-l-Araf-(1→. Immunomodulatory assay indicated that SMP-3a could significantly promote the proliferation of macrophages and stimulate the secretion of cytokines, including TNF-α, IL-1β, and IL-6. Our results suggested that SMP-3a could be used as a novel potential immunomodulatory agent in functional food.


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