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Due to the high similarity with the lipid layer between human skin keratinocytes, functional cosmetics with layered liquid crystal structure prepared by liquid crystal emulsification technology encapsulating natural active substances have become a hot research topic in recent years. This type of functional cosmetic often has a fresh and natural skin feel, excellent skin barrier repair function and efficient moisturizing effect, etc., showing great potential in cosmetic application. However, the present research on the application of liquid crystal emulsification technology to functional cosmetics is still in the initial stage, and there are fewer relevant reports with reference values. Based on the mentioned above, this review provides a comprehensive summary of functional cosmetics with layered liquid crystal structures prepared by liquid crystal emulsification technology from the following aspects: the structure of human skin, the composition of lamellar liquid crystal, the advantages of liquid crystal emulsification technology containing natural active substances used in the field of functional cosmetics, the preparation process, main components, influencing factors during the preparation and the market functional cosmetics with lamellar liquid crystal structure. Finally, the prospect of the application of liquid crystal emulsification technology in functional cosmetics is presented, to provide useful references for those engaged in the research of liquid crystal emulsification technology-related functional cosmetics.
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Long-acting analgesia is a common clinical treatment method after surgery. The slow-release injection with long-acting analgesia has the advantages of less medication frequency and stable effect. In this study, the analgesic drug lappaconitine hydrobromide lyotropic liquid crystal injection was prepared, and its sustained release mechanism, drug release and pharmacodynamic characteristics were evaluated. The results of polarizing microscope and freeze-transmission electron microscope showed that the lyotropic liquid crystal injection of the liquid crystal precursor preparation of lappaconitine hydrobromide could be obtained by the combination of glycerol monooleate (GMO) and soybean lecithin (SPC) in different proportions. The results of dissolution study in vitro showed that the drug release rate of different forms of liquid crystal preparations was layered liquid crystal > cubic liquid crystal > hexagonal liquid crystal. The mathematical model fitting results of the release data showed that the external release of layered liquid crystal, cubic liquid crystal and hexagonal liquid crystal conforms to the Ritger-Peppas model, and the release mechanism was Fick diffusion. The results of pharmacodynamics study in vivo showed that the analgesic effect of lappaconitine hydrobromide lyotropic liquid crystal injection lasted for 3 days, and there was no abnormality in the incision and local tissue, showing good safety and tolerance. The study on drug release and elimination process of the in vivo gel repository showed that lappaconitine hydrobromide could be completely released from the lyotropic liquid crystal 3 days after administration, and the sustained-release materials could be gradually eliminated locally. All animal experiments were approved by the Experimental Animal Ethics Committee of the Shanghai Institute of Materia Medica, Chinese Academy of Sciences (No. 2021-08-GY-61) and the experiments were conducted in accordance with the relevant guiding principles and regulations. The lyotropic liquid crystal injection of lappaconitine hydrobromide prepared in this study presented a solution state at room temperature, and underwent phase transition in contact with the body fluid at the administration site, formed a drug depot and exerted a slow drug release effect. This preparation can reduce systemic toxicity, prolong the duration of analgesia, reduce the number of administrations, improve the compliance of postoperative patients, and provide a reference for the design of long-term sustained release analgesic preparations.
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The article was to study the effect of local photodynamics therapy combined with carbon dioxide lattice laser - "light needles" for the treatment of basal cell carcinoma (BCC). 5-Aminolevulinic acid (5-ALA) cubic liquid crystal using glyceryl monostearate (GMO) as the substrate was prepared. The cytotoxicity of 5-ALA cubic liquid crystal combined with light needles in vitro were evaluated. The pharmacodynamics study of 5-ALA cubic liquid crystal combined with light needles of high or low energy for BCC was carried out based on the pathological changes, tumor volume, vascular endothelial growth factor (VEGF) expression and the recurrence rate, which has been approved by the Ethics Committee of Beijing Institute of Radiation Medicine. The cubic liquid crystal was isotropic with the lattice of PN3M. The cytotoxicity of 5-ALA cubic liquid crystal combined with light needles was much higher than that of 5-ALA or light needles alone. Compared with light needles or photodynamic therapy alone, 5-ALA cubic liquid crystal combined with light needles of high energy could prevent the BCC metastasis and of low energy could inhibit BCC growth. It demonstrated the obvious therapeutical effects for BCC. 5-ALA cubic liquid crystal combined with light needles can effectively treat BCC, which provides a new choice for clinical BCC treatment.
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Lyotropic liquid crystal is an ordered system with various geometric shapes or three-dimensional structures formed by the interaction of amphiphilic molecules dissolved in polar solvents, and has the characteristics of excellent drug applicability, high drug loading, good bioadhesive property and high transdermal permeability. Through a comprehensive analysis of the research results in this research group and the related research reports of LLC drug delivery system, the authors systematically discussed the research value, development potential and research status of LLC in the field of new drug delivery system of traditional Chinese medicine(TCM), especially in the percutaneous and mucosal drug delivery system and the oral microparticle drug delivery system of TCM. At the same time, due to the current research field of TCM-LLC drug delivery system starts late, many of the basic research problems to be further perfect, this paper had carried on the induction summary to these problems, and put forward the research countermeasures:①the basic research of TCM-LLC drug delivery system should be strengthened by referencing the research experience and methods of LLC drug delivery system of single chemical component combined with TCM characteristics, ②the research on the release mechanism of the chemical components in TCM should be strengthened, and the basic research on the LLC drug delivery system of synchronized sustained release TCM should be carried out, ③development of new LLC materials applicable to TCM, ④the quality evaluation system of TCM-LLC should be improved, ⑤to explore the LLC preparation process suitable for industrialization.
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OBJECTIVE: To prepare and characterize triptolide cubic liquidcrystal,study the rheological properties and in vitro transdermal properties. METHODS: Cubic liquid crystal (V2) was prepared by using phytantriol-carbitol-water three-component system. Using the ternary phase diagram method to optimize the target area. V2 was characterized by small-angle X-ray scattering, infrared spectroscopy and differential scanning calorimetry. Rheological properties of V2 was studied by a DHR-2 rheometer. In vitro drug release studies were conducted by using improved Franz diffusion cell method. RESULTS: SAXS is shown as double-diamond lattice cubic liquid crystal; rheological parameters are good; DSC results show V2 can be converted into a hexagonal phase at 65.5 ℃ and converted into a layered liquid crystal at 90 ℃, and the addition of the drug does not change the liquid crystal structure. In vitro transdermal cumulative permeation amount is about 1.54 times that of the gel, and the sustained release of triptolide can be as long as 48 h. CONCLUSION: The prepared triptolide liquid crystal has good appearance and suitable rheology, and its cumulative permeation amount and infiltration rate of V2 are superior to the hydrophilic gel, which provides theoretical reference for triptolide percutaneous administration.
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Lyotropic liquid crystal(LLC) is generally a kind of micelle association formed by self-assembly of amphiphilic lipid polymers in polar solvents. It have been applied in the study of drug delivery of administration of oral, skin injection, ocular, and cavity channel routes(including buccal cavity, nasal cavity, vagina), et al. Medical liquid crystal mainly includes lamellar phase, inverse hexagonal phase and inverse cubic phase. Inner assembling order in different structures of liquid crystals will affect the drug localization, viscosity, molecular interactions, and further drug release in vitro and in vivo, pharmacokinetics and so on. Thus, it is very important to characterize their microstructures. In this article, the characterization methods of LLC microstructures are comprehensively described based on the research of LLC as drug delivery carrier and related literatures, which can provide reference for further study of LLC drug delivery system.
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Three different kinds of sinomenine in situ liquid crystal were prepared for different prescriptions, to investigate the rheological properties before and after in situ treatment and evaluate its feasibility for embolization. Rheological experiments were carried out with cone plate fixtures. Both the steady-state rheological and non-steady-state rheological properties of in-situ gels and the swelling gels were studied and compared. Steady-state rheological study results showed that all the three liquid embolic agents were non-newtonian fluid before and after in situ treatment, which would become less ropy when they were pressed with shear stress; their viscosities differed by 2-5 orders of magnitude. It had a yield value of about 10 Pa before in situ treatment and about 4 500 Pa after in situ treatment. All the six systems had thixotropy while their dynamic viscosities were not influenced by the shear rate, all less than 0.3 Pa·s before in situ treatment more than 1 Pa·s after in situ treatment, differing by an order of magnitude. The results of temperature sweeping showed a slight decrease with a steady rate in viscosity within the range of 10-50 °C, differing by 3-4 orders of magnitude. The results of unsteady rheology showed that there was no obvious linear viscoelastic region in the three kinds of agents, indicating the properties of liquid. After in situ treatment, their linear viscoelastic range γ<1% (No.3 was 5%), and their elastic modulus G' was larger than the viscous modulus G", indicating the properties of solid. Frequency scanning results showed that for the systems at low frequencies, G">G', system viscosity in a dominant position; while at high frequencies, G'>G", system elasticity in a dominant position. The results of compound viscosity test also proved that the liquid embolic agent in situ can form a cubic liquid crystal (the structure of No. 3 was destroyed after in situ treatment). The DHR-2 rheometer was used to investigate the rheological properties of in situ gels with three different prescriptions. The method is simple and the result is reliable, which can provide more theoretical reference for the evaluation and practical application of the product.
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@#Lyotropic liquid crystal system is formed by the amphiphilic molecules dissolving in polar solvents with a special geometric structure. Lamellar, cubic and hexagonal mesophases are some of the most common lyotropic liquid crystal systems. Recently, they have attracted much research attention because of their distinctive structures and physico-chemical properties(like strong bioadhesion, high permeability, low liquidity, and slow released drug), and have been widely used as carriers for drug delivery systems, especially in transdermal and mucosal fields. According to the research about lyotropic liquid crystal and nasal route of administration in our group, and the related references in recent years, we investigate the technical strategies about the using of lyotropic liquid crystal in transdermal and mucosal drug delivery system. Among them, we specially put the emphasis on the application prospects of lyotropic liquid crystal in the nasal mucosal administration, and then provide a theoretical basis and future research directions in the development of lyotropic liquid crystal in transdermal and mucosal administration fields.
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This review introduced the formation, structural characteristics of lyotropic liquid crystals and the recent progress in study on lyotropic liquid crystals as drug delivery system. The authors analyzed the advantages, prospect and existing problems of lyotropic liquid crystals as drug delivery system. This review emphasized the effect of additives on lyotropic liquid crystals and provided a reference for further study on lyotropic liquid crystals as drug delivery system.
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ABSTRACT Various approaches have been taken to improve our knowledge of the microenvironmental regulation of limbal epithelial stem cells. Researchers have extensively investigated the roles of growth factors, survival factors, cytokines, enzymes, and permeable molecules secreted by the limbal cells. However, recent evidence suggests that stem cell fate (i.e., self-renewal or differentiation) can also be influenced by biophysical and mechanical cues related to the supramolecular organization and the liquid crystalline (mesophase) nature of the stromal extracellular matrix. These cues can be sensed by stem cells and transduced into intracellular biochemical and functional responses, a process known as mechanotransduction. The objective of this review is to offer perspectives on the supramolecular microenvironmental regulation of limbal epithelial stem cells and the differentiation of their progeny.
RESUMO Muitas abordagens têm sido utilizadas para ampliar entendimentos sobre a regulação microambiental das células tronco epiteliais limbais. Neste contexto, pesquisadores têm exaustivamente investigado a participação de fatores de crescimento, fatores de sobrevida, citocinas, enzimas e moléculas permeáveis secretadas pelas células limbais. Entretanto, evidências recentes sugerem que o destino (ie. autorrenovação ou recrutamento para a via de diferenciação) das células tronco também sofre influência de estímulos biofísicos ou mecânicos relacionados à organização supramolecular e à natureza liquido-cristalina (mesofases) da matriz extracelular estromal. Esses estímulos podem ser percebidos e traduzidos pelas células tronco em sinais bioquímicos que geram respostas funcionais, através de um processo designado de mecanotransdução. Objetiva-se, com a presente revisão, oferecer ao leitor perspectivas supramoleculares sobre a regulação microambiental das células tronco epiteliais limbais e a diferenciação de sua progênie.
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Humans , Stem Cells/physiology , Cell Differentiation/physiology , Limbus Corneae/cytology , Epithelium, Corneal/cytology , Mechanotransduction, Cellular/physiology , Extracellular Matrix/physiology , Epithelium, Corneal/physiology , Stem Cell Niche/physiologyABSTRACT
OBJECTIVE: To prepare and characterize sinomenine liquid crystal gel, study the rheological properties and in vitro transdermal properties and compare with sinomenine ointment and sinomenine hydrophilic gel. METHODS: Sinomenine liquid crystal gel was prepared by using phytanetriol-water system and then characterized by polarized light microscope(PLM)and small angle X-ray diffraction(SAXS). Using DHR-2 rheometer, the rheological properties of sinomenine liquid crystal gel were investigated and compared with those of sinomenine ointment and sinomenine hydrophilic gel. Modified Franz diffusion cell was used for in vitro transdermal experiment and the in vitro transdermal properties were compared with sinomenine hydrogels and ointments. RESULTS: The appearance of sinomenine liquid crystal gel was colorless, clear and transparent, and showed dark field under PLM. SAXS showed cubic phase. The rheological parameters were good. The steady-state infiltration rates of sinomenine liquid crystal gel, ointment and hydrophilic gel were 153.93, 119.99, and 106.89 μg·cm-2·h-1, and their 48 h cumulative permeation amounts(%)were 93.76%, 91.55%, and 87.60%, respectively. CONCLUSION: PLM and SAXS can be used to characterize the liquid crystal gel.The prepared sinomenine liquid crystal gel has good appearance and suitable rheology, and its infiltration rate and 48 h cumulative permeation amount are superior to those of ointment and hydrophilic gel, which provides theoretical reference for sinomenine percutaneous administration.
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ABSTRACT Liquid crystal systems (LCSs) have interesting cosmetic applications because of their ability to increase the therapeutic efficiency and solubility of active ingredients. The aim of the present research was to develop green tea glycolic extract-loaded LCSs, to characterize and to perform microbiological control. The ternary phase diagram was constructed using polysorbate 20, silicone glycol copolymer (SGC) - DC 193(r), and distilled water with 1.5% glycolic green tea extract. The systems were characterized by polarized light microscopy. Formulations selected were characterized as transparent viscous systems and transparent liquid system indicated mesophases lamellar structure. The results of the microbiological analysis of mesophilic aerobic microorganisms (bacteria and fungi) revealed that the above formulation showed a biologic load <10 CFU/mL in all samples. In conclusion, liquid crystalline systems that have presented formation of a lamellar mesophases were developed. Furthermore, the formulation and products tested presented the adequate microbiological quality in accordance with official recommendations.
Subject(s)
/analysis , Camellia sinensis/classification , Liquid Crystals/microbiology , Liquid Crystals , Cosmetics/analysis , Cosmetic MicrobiologyABSTRACT
@#The aim of the study was to investigate the effect of oleic acid(OA)and isosorbide mononitrate(ISMN)on the phase diagrams of glyceryl monooleate(GMO)liquid crystalline systems and release of ISMN from them. Liquid crystalline systems of GMO/H2O, GMO/H2O/ISMN and GMO/H2O/OA were prepared and their phase diagrams were plotted. Investigation of water absorption of GMO and ISMN release profiles shown that the release mechanism of ISMN was diffusion-controlled. Increased drug loading accelerated the release rate. However, the increased loading of OA decreased ISMN release. The result could offer practical basis for drug loading and the selection of additives in GMO liquid crystalline system.
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Phytantriol (PT), ethanol (ET) and water were used to prepare in situ cubic liquid crystal (ISV2). The pseudo-ternary phase diagram of PT-ET-water was constructed and isotropic solution formulations were chosen for further optimization. The physicochemical properties of isotropic solution formulations were evaluated to optimize the composition of ISV2. In situ hexagonal liquid crystals (ISH2) were prepared based on the composition of ISV2 with the addition of vitamin E acetate (VitEA) and the amount of VitEA was optimized by in vitro release behavior. The phase structures of liquid crystalline gels formed by ISV2 and ISH2 in excess water were confirmed by crossed polarized light microscopy and small angle X-ray scattering, respectively. Rheological properties of ISV2 and ISH2 were studied by a DHR-2 rheometer. In vitro drug release studies were conducted by using a dialysis membrane diffusion method. Pharmacokinetics was investigated by determination of sinomenine hydrochloride (SMH) concentration in synovial membrane after intra-articular injection of SMH-loaded ISH2 in adjuvant-induced arthritis rats. The optimal ISV2 (PT/ET/water, 64:16:20, w/w/w) loaded with 6 mg·g-1 of SMH showed a suitable pH, injectable and formed a cubic liquid crystalline gel in situ with minimum water absorption in the shortest time. The optimal ISV2 was able to sustain the drug release for 144 h. The optimal ISH2 system was prepared by addition of 5% VitEA into PT in the optimal ISV2 system. This ISH2 (PT/VitEA/ET/water, 60.8:3.2:16:20, w/w/w/w) was an injectable isotropic solution with suitable pH. The new ISH2 was able to sustain the drug release for more than 240 h. Local pharmacokinetics study indicated that the retention time and AUC0-∞ of ISH2 group were increased significantly compared with that of SMH solution group and the AUC0-∞ of ISH2 group was 6.01 times higher than that of SMH solution group. The developed ISH2 was suitable for intra-articular injection that may apply to patients in the treatment of rheumatoid arthritis.
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[ ABSTRACT] AIM:To develop the cell model of polymer/liquid crystal and to study the effect of their elasticity on the adhesion of rat bone marrow mesenchymal stem cells (rBM-MSCs).METHODS: Using the method of solvent e-vaporation induced phase separation, the cell model of polymer/liquid crystal was constructed.The surface morphology and phase separation structure were determined by polarized optical microscopy ( POM) , scanning electron microscopy ( SEM) and small angle X-ray scattering ( SAXS ) .rBM-MSCs were separated and expanded by adherent culture.The surface markers of rBM-MSCs were detected by flow cytometry.The cells were induced to osteogenic differentiation and adipogenic differentiation for 2 weeks.After 3 passages, the cells were divided into 4 groups, including total PU control group, 10%membrane group, 30%membrane group and 50%membrane group.The cells were then incubated with rhodamine phalloi-din for cytoskeleton staining and were observed under the confocal laser scanning microscope after cultured for 24 h.RE-SULTS:The cell model of polymer/liquid crystal was constructed successfully using the method of solvent evaporation in-duced phase separation.Flow cytometry results showed that the rBM-MSCs positively expressed CD29, CD44 and CD90, and negatively expressed CD34 and CD45.After stained with alizarin red S and oil red O, the calcium nodule and lipid droplets in rBM-MSCs were observed obviously.The cytoskeleton staining result indicated that the area in total PU control group, 10%membrane group and 30%membrane group were greater, and the actin microfilaments were also clearer than that in 50%membrane group.CONCLUSION:The cell model with suitable content of liquid crystal made a contribution to the rBM-MSCs’ adhesion, but too much liquid crystal inhibits cell adhesion.
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OBJETIVO: O objetivo deste trabalho foi avaliar o desempenho de 24 monitores LCD utilizados nos laudos médicos, segundo testes recomendados pelo AAPM Report 03, de 2005. MATERIAL E MÉ-TODO: Os testes foram realizados de acordo com o AAPM Report 03 de 2005, em parâmetros como: distorção geométrica, reflexão, uniformidade e resposta de luminância, contraste, resolução, ruído e velamento por reflexão interna, com auxílio de fotômetro ou visualmente. RESULTADOS: Apresentaram-se problemas de: ruído (38% das estações de trabalho), resposta de luminância econtraste (33%) e uniformidade da luminância (4%). CONCLUSÃO: Em razão de o modelo MDNC4130 estar configurado para maximizar a vida útil, sua luminância é baixa, fazendo com que ruídos causados por sujeira comprometam a imagem. Em retestes, mostrou-se que a limpeza periódica dosmonitores resolve este problema. Já no caso das não conformidades em luminância e contraste, percebeu-se que a calibração automática com o software do monitor nem sempre corrige as distorções apresentadas.
OBJECTIVE: The purpose of this paper was to investigate the imagequality of 24 display devices and to compare the results of performance. MATERIAL AND METHOD: Tests were executed following AAPM Report 03 on 24 display devices installed in the Instituto de Radiologia do Hospital das Clínicas, São Paulo, SP, Brazil.The evaluation of test pattern considered these parameters:geometric distortions, luminance uniformity and response, contrast,reflections, resolution, and noise. RESULTS: The problems found were: noise (38% of workstations), luminance and contrast (33%) and luminance uniformity (4%). CONCLUSION: The model MDNC4130 was setting to preserve the life of display device, then the luminance is low, making the noise caused by dirt compromising image. The new test showed that regular cleaning of displaydevices solves this problem. In the case of non compliance of luminance and constrast realized that the automatic calibration of the display devices is not always correct the distortions.
Subject(s)
Liquid Crystals , Monitoring Stations , Quality Control , Radiographic Image Enhancement , RadiologyABSTRACT
OBJETIVO: O objetivo deste trabalho foi avaliar o desempenho de 24 monitores LCD utilizados noslaudos médicos, segundo testes recomendados pela AAPM Report 03, de 2005. MATERIAL E MÉ-TODO: Os testes foram realizados de acordo com o AAPM Report 03 de 2005 em parâmetros como:distorção geométrica, reflexão, uniformidade e resposta de luminância, contraste, resolução, ruído e velamento por reflexão interna, com auxílio de fotômetro ou visualmente. RESULTADOS: Apresentaram-se problemas de ruído (38% das estações de trabalho), resposta de luminância e contraste (33%) e uniformidade da luminância (4%). CONCLUSÃO: Em razão de o modelo MDNC4130 estarconfigurado para maximizar a vida útil, sua luminância é baixa, fazendo com que ruídos causados por sujeira comprometam a imagem. Em retestes, mostrou-se que a limpeza periódica dos monitores resolve este problema. Já no caso das não conformidades em luminância e contraste, percebeu-se que a calibração automática com o software do monitor nem sempre corrige as distorções apresentadas.
OBJECTIVE: The purpose of this paper was to investigate the imagequality of 24 display devices and to compare the results of performance. MATERIAL AND METHOD: Tests were executed following AAPM Report 03 on 24 display devices installed in Instituto de Radiologia do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, São Paulo, SP, Brazil. The evaluation of test pattern considered these parameters: geometric distortions, luminance uniformity and response, contrast, reflections, resolution, and noise. RESULTS: The problems found were: noise (38% of workstations), luminance and contrast (33%) and luminance uniformity (4%). CONCLUSION: The model MDNC4130 was setting to preserve the life of display device, then the luminance is low, making the noise caused by dirt compromising image. The new testshowed that regular cleaning of display devices solves this problem.In the case of non compliance of luminance and contrast realized that the automatic calibration of the display devices is not always correct the distortions.
Subject(s)
Expert Testimony , Magnetic Resonance Spectroscopy , Radiographic Image Enhancement , Tomography, X-Ray Computed , Television , Quality ControlABSTRACT
Objective To assess the influence of medical monochrome liquid crystal displays (LCD) with different resolutions for the detection performance of micro-nodules (diameter <10 mm) on chest radiograms. Methods Eighty-seven DR chest images that were verified with CT were selected from PACS on-line, including 32 positive images, 32 suspected images and 23 normal images. The diameters of all nodules were lower than 10 mm. Three of high-, mid- and low-experienced radiologists who participated in the ROC study interpreted these 87 images using three types of LCDs with different resolutions, respectively. Regarding the presence of nodule, five-point confidence level rating scale was used, i.e. definitely absent, probably absent, possibly present, probably present and definitely present. All observers marked their confidence levels of every image according to the presence of pulmonary nodule on different displays. Software SPSS 13.0 was used for statistical analysis. Results AUC increased with the increasing resolutions and radiologists' experiences in 2MP, 3MP, 5MP displays. For the detection performance of pulmonary nodules (diameter <10 mm), there was no significant difference among different types of displays or different aptitudes of radiologists. Conclusion It's equivalent for the detection performance of pulmonary nodule (diameter <10 mm) on 2MP, 3MP and 5MP medical monochrome LCD when no restriction on the use of image post-processing tools. Highly-experienced radiologist can get the most information when using 5MP display. It is advisable to combine the diagnostic workstation system with high-, mid- and low-resolution monitors, and reasonable equipment scheme between different types of displays and different aptitudes of radiologists could result in better cost-efficacy.
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Objective To study the relationship between the selection of tube tension in digitalchest radiograph and image quality.Methods When tube current was fixed at 4 mAs, the choice of X-ray tube voltage changed from 60 to 120 kV.CDRAD2.0 contrast details phantom and normal human chest were exposed by X-ray system with 7 kinds of tube voltage (the difference between tube voltage was 10 kV) ,and the X-ray incidental dose of phantom surface was measured.Five radiologists with 3 years working experience evaluated the image quality on monitor and calculated the image quality factor (IQF) and image reading score.Statistics analysis was then performed by using ANOVA test and t test.According to the results, the optimum tube voltage range was determined.Results (1) The incidental dose of phantom surface increased with the higher tube voltage.(2)When the tube voltage was changed from 60 kV to 120 kV, the IQF value observed in CDRAD2.0 phantom image on monitor was 75.0±10.4,57.1±6.4,52.7±2.5,47.9±4.5, 46.0±3.8,46.0±2.8,45.2±3.5 ,there was significant statistical differences between groups(F=19.10, P<0.01).(3)The integrated score of the chest image quality in the tube voltage 90 kV and 120 kV were 12.4±0.9 and 13.0±0.7, respectively, and there was no statistical difference between two groups(t= 1.500,P>0.05).Conclusions (1)With the increase of tube tension,the display capacity of display device gradually strengthened.When the tube tension exceeded 90 kV, the increase of image quality on monitor was not evident.(2) With proper radiation dose, the value of tube tension in digital X-ray chest photograph was about 90 kV.
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The military portable ECG for triage is a kind of minitype monitoring equipment for life information for the purpose that the ambulanceman carry through first aids in frontline. Life information of the wounded will be acquired exactly and quickly applying with this equipment, then quickening the triage and reducing the casualties. The system is based on C8051F310 single chip microcomputer, applying with high accuracy, low offset drift instrumentation amplifier AD620 and ultra low power LCM LMS019 to display real-time and accurate ECG signal sampled. The equipment is easy to use and inexpensive, suitable for mass requirement of our field army.