Analysis of current γ knife stability testing status in medical institutions / 中国职业医学

@#Abstract: Objective To follow up and evaluate the stability testing status of γ stereotactic radiotherapy system (hereinafter γ knife WS 582-2017 Specifications for Testing of Quality Control in X and γ referred to ) in medical institutions based on the RayStereotactic Radiotherapy System WS 582-2017 Methods (hereinafter referred to ). A total of 43 medical institutions using γ knife and 54 medical physics personnel were recruited as the research subjects by random sampling method. Based on the - - standard tracking evaluation method, we followed up the evaluation of γ knife stability testing based on WS 582 2017. Results - Only 66.7% of the 54 subjects preformed WS 582 2017 in their daily work. Only 30.2% (all were tertiary hospital) of 43 medical institutions were equipped with complete quality control and testing equipment. The implementation rate of γ knife stability test was 67.4%, and it was not carried out in strict accordance with the test events and test cycle requirements - specified in the WS 582 2017. There were incomplete test events, incomplete records or test cycles that did not meet the Conclusion standard requirements in γ knife stability test. Medical institutions did not carry out γ knife stability tests in strict - accordance with the projects and cycle required by the WS 582 2017. The reasons are related to medical institutions are not equipped with complete testing equipment, the personnel are lack of understanding of relevant national standards, the poor publicity and implementation of the standards, the lack of standardized training channels and inadequate health supervision.

Genetic analysis of some morphological traits in synthetic x naturally polyploid cotton derivatives

Cotton has received attention of geneticists since more than a century. Gossypium hirsutum, the predominantly cultivated cotton species worldwide, has a narrow genetic base. It is important to broaden its genetic base through introgression of novel alleles from related species. Here, we report the development and characterization of a backcross population derived from the hybridization of a ‘synthetic’ (derived by crossing and chromosomal doubling of nonprogenitor Gossypium species) and natural tetraploid upland cotton. ‘Synthetic’ was observed to be male-sterile and thus, was used as the female parent. A total of 7434 flowers were pollinated to obtain 1868 BC1F1 seeds by direct and reciprocal crosses. Characterization of the experimental plant material was conducted in the field for several morphological traits such as pubescence on the stem, leaf, petiole and bract, presence/absence of petal spot, petal margin colouration and stamen filament colouration. Genetic analysis revealed that petal margin colouration phenotype was governed by a single dominant gene, whereas the petal spot and filament colouration phenotypes manifested segregation distortion. None of the BC1F1 plants was devoid of trichomes thus demonstrating that presence of trichomes is dominant over their absence. Modern upland cotton cultivars are usually devoid of petal spot, petal margin colouration and stamen filament colouration. These floral anthocyanin pigmentation characteristics, if fixed in the cotton germplasm, may serve as diagnostic features for the identification of cultivars during DUS testing as well as in the maintenance breeding programmes

PEG-PCL Nanocapsules Containing Curcumin: Validation of HPLC Method for Analyzing Drug-loading Efficiency, Stability Testing and Cytotoxicity on NIH-3T3 Cell Line

Abstract Curcumin (CUR) shows potential use for treating cancer. However, CUR has low solubility and reduced bioavailability, which limit its clinical effect. Therefore, the development of nanocarriers can overcome these problems and can ensure the desired pharmacological effect. In addition, it is mandatory to prove the quality, the efficacy, and the safety for a novel nanomedicine to be approved. In that sense, this paper aimed (a) to prepare CUR-loaded polyethylene glycol-poly(ε-caprolactone) nanocapsules; (b) to validate an analytical method by high performance liquid chromatography (HPLC) for quantifying CUR in these nanoformulations; (c) to evaluate the physicochemical stability of these formulations; and to investigate their cytotoxicity on NIH-3T3 mouse fibroblast cells. The HPLC method was specific to CUR in the loaded nanocapsules, linear (r = 0.9994) in a range of 10.0 to 90.0 µg.mL-1 with limits of detection and quantification of 0.160 and 0.480 µg.mL-1, respectively. Precision was demonstrated by a relative standard deviation lower than 5%. Suitable accuracy (102.37 ± 0.92%) was obtained. Values of pH, particle size, polydispersity index, and zeta potential presented no statistical difference (p > 0.05) for CUR-loaded nanoparticles. No cytotoxicity was observed against NIH-3T3 mouse embryo fibroblast cell line using both the tetrazolium salt and sulforhodamine B assays. In conclusion, a simple and inexpensive HPLC method was validated for the CUR quantification in the suspensions of nanocapsules. The obtained polymeric nanocapsules containing CUR showed suitable results for all the performed assays and can be further investigated as a feasible novel approach for cancer treatment.

Development And In Vitro Evaluation Of A New Topical O/W Emulgel From Fruit Extract Of Pyrus Communis

Objective: The aim of the present study was to develop a new topical dosage form containing Pyrus communis fruit extract. Developed formulation was O/W Emulgel which was evaluated by its in vitro tests and its stability studies at different storage conditions. Methods: Hydroalcoholic Pyrus communis extract was prepared by the maceration process. A 4% Pyrus communis emulgel was prepared by the combination of emulsion and gel at a specific temperature and mixing through homogenizers. The formulations having different concentration of carbopol 940 (gelling agent) were placed at 8 °C, 25 °C, 40 °C and 40 °C+75%RH for 3 mo in order to find out the most stable formulation. After the selection of final emulgel formulation was eventually further evaluated for in vitro studies such as phase separation, centrifugation, rheology, pH, conductivity, organoleptic properties and mean droplet size over a period of 12 w at 8 °C, 25 °C, 40 °C and 40 °C+75%RH. Results: In vitro evaluation of the selected Pyrus communis emulgel formulation showed good resistance to phase separation on centrifugation, conductivity gradually increases due to oil in water emulgel and pH of formulation was gradually decreased. The rheological behavior was non-Newtonian pseudoplastic and showed shear thinning fluid behavior. Mean droplet size of Pyrus communis emulgel was 16.0±0.20 µm and after 90 d droplet size was 16.7±0.55 µm at high storage temperatures at 40 °C and 40 °C+75RH and no significant changes were observed at normal storage conditions at 8 °C and 25 °C. Conclusion: Pyrus communis emulgel fresh fruit extract showed stable formulation at different storage conditions. This new formulation will be a good addition to pharmaceutical dosage forms made from traditionally used plants.

The impact of storage conditions upon gentamicin coated antimicrobial implants☆ / 药物分析学报

A systematic approach was developed to investigate the stability of gentamicin sulfate (GS) and GS/poly (lactic-co-glycolic acid) (PLGA) coatings on hydroxyapatite surfaces. The influence of environmental factors (light, humidity, oxidation and heat) upon degradation of the drug in the coatings was investigated using liquid chromatography with evaporative light scattering detection and mass spectrometry. GS coated rods were found to be stable across the range of environments assessed, with only an oxidizing atmosphere resulting in significant changes to the gentamicin composition. In contrast, rods coated with GS/PLGA were more sensitive to storage conditions with compositional changes being detected after storage at 60 °C, 75%relative humidity or exposure to light. The effect of γ-irradiation on the coated rods was also investigated and found to have no significant effect. Finally, liquid chromatography–mass spectrometry analysis revealed that known gentamines C1, C1a and C2 were the major degradants formed. Forced degradation of gentamicin coatings did not produce any unexpected degradants or impurities.

Stability Testing of Pharmaceutical Products.

Stability studies ensuring the maintenance of product quality, safety and efficacy throughout the shelf life are considered as pre-requisite for the acceptance and approval of any pharmaceutical product. These studies are required to be conducted in a planned way following the guidelines issued by ICH, WHO and or other agencies. Importance of various methods followed for stability testing of pharmaceutical products, guidelines issued for stability testing and other aspects related to stability of pharmaceutical products have been presented in a concise manner in the present review.