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To improve the efficacy of 5-aminolevulinic acid (5-ALA)-mediated photodynamic therapy (PDT), a fluorocarbon microemulsion-based gel (FMBG) loaded with both 5-ALA and carbon dioxide (CO2) was prepared in this study. Its physical and chemical properties such as particle size, zeta potential, morphology, pH value and viscosity were characterized. Acid-base titration experiment was used to determine the CO2 loading, a fluorescence derivatization method was established to determine the content of 5-ALA, and the confocal laser scanning microscope and Franz diffusion cell method were carried out to investigate its transdermal ability. Through the laser speckle contrast imaging, the CO2-affected blood flow perfusion of skin was measured. Finally, the skin irritation test was tested by hematoxylin-eosin staining (H&E) method. These results showed that the prepared FMBG was a milky white gel, with an average particle size of 202.4 nm, a zeta potential of -25.3 mV, a pH of 6.0, and a viscosity of 1 062.0 mPa·s. It can be stored stably for seven days at room temperature. The 5-ALA content of FMBG was measured to be approximately equal to 20% (w/w). At room temperature and normal pressure, the CO2 loading content of FMBG was 5.016 mg·L-1, which was 1.5 times as much as that of water. The transdermal absorption experiment and blood perfusion results showed that the FMBG can effectively enable the transdermal delivery of 5-ALA and CO2, and significantly increased the blood perfusion of skin. H&E staining results indicated that FMBG had negligible skin irritation (all animal tests were approved by the Ethics Committee of 900 Hospital of the Joint Logistics Team). In this study, a safe and stable FMBG loaded with both 5-ALA and CO2 was successfully prepared. It was suitable for transdermal application, having the potential of enhancing the efficacy of 5-ALA-mediated PDT.
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Objective: To prepare the liposomes carrying doxorubicin hydrochloride (DOX) and liquid fluorocarbon (PFH) in liquid form based liposomes (Lip-PFH-DOX), and to investigate the Lip-PFH-DOX nanoparticle enhanced ultrasound imaging and its therapeutic effect on human breast cancer MAD-MB-231 cells. Methods: Lip-PFH-DOX nanoparticles were prepared by using biocompatible phospholipid mixture as film-forming material and lipophilic DOX as additive. The morphology, particle size, potential and encapsulation efficiency of Lip-PFH-DOX nanoparticles were tested. Low intensity focused ultrasound was used to induce phase transition and rupture of nanoparticles. High performance liquid chromatography was used to detect drug release at different time points. The cytotoxic effect of the nanoparticles on human breast cancer MDA-MB-231 cells was detected and the apoptosis was observed. A nude mouse breast cancer mda-mb-231 model was established, and an appropriate amount of nanoparticles were injected into the tail vein to observe the enhanced ultrasound at the tumor site. Results: The liposomes loaded with DOX and PFH were successfully prepared. The particle size was (340.81±68.54)nm, the potential was (-17.72±7.66)mV, and the drug encapsulation rate was (86.80±2.55)%. Under transmission electron microscopy, the drug was successfully encapsulated in the liposomes. Under light microscopy, the liposomes were uniform in size, and the phase transition was occured. In vitro, the release rate of DOX of Lip-PFH-DOX reached 40.05±3.22 at 48 h. After 48 h, when the concentration was 100 μg/ml of Lip-PFH-DOX, the survival rate decreased to 45.00%. Lip-PFH-DOX and the nanoparticles can significantly enhance ultrasound development in vivo after low intensity ultrasound irradiation. Conclusion: The nanoparticles of DOX and PFH was successfully prepared, which can achieve ultrasound development in vivo and in vitro, and DOX can kill MAD-MB-231 cells.
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Objective To investigate the therapeutic effect of high intensity focused ultrasound (HIFU) ablation combined with homemade liquid fluorocarbon nanoparticles on cervical cancer in nude mice.Methods The cell experiment was divided into three groups:a,control group;b,HIFU group;c, HIFU + PFB nanoparticle group,and the viability of cells was detected using CCK-8 reagent.The mice were also divided into three groups:A,0.9% NaCI group;B,HIFU + 0.9% NaCI group;C,HIFU + PFB nanoparticle group. The tumors were removed and underwent triphenyl tetrazolium chloride(TTC) staining,and the necrosis area was measured.Histopathological changes of the tumors were examined by light microscopy.Results After HIFU irradiation,the viability rate of group c was (40.5 ±9.7)%,it was lower than that of group b (77.7 ±8.5)% (P <0.05) and that of group a(100 ±4.8)% (P <0.05). TTC staining of tumor showed a large scale of necrotic tissue in group C.The necrosis ratio of the three groups was 0%,(34.14±12.2)% and (65.97 ±25.1)%,respectively (P <0.05).HE staining showed karyorrhexis or an absence of nuclei in group B and group C,which demonstrated the coagulation necrosis. Conclusions HIFU ablation combined with liquid fluorocarbon nanoparticles can effectively treat the xenograft model of the human cervical carcinoma in nude mice.
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Retinoschisis is an abnormal separation of the retinal layers and is asymptomatic in most cases. Enlargement of the area of retinoschisis and retinal tear and detachment are possible complications of the disease, and the treatment of retinoschisis is controversial. In this case report, we present a case of retinal detachment associated with senile retinoschisis in which pneumatic retinopexy was chosen as the treatment of choice and was performed successfully in one of the eyes. After a literature review on retinoschisis and pneumatic retinopexy for the treatment of associated retinal detachment, we found only one case that was successfully treated without drainage of subretinal fluid, using air as the filler. However, no previous reports have been found in the literature on the effectiveness of pneumatic retinopexy using C3F8 as the sole treatment for progressive retinal detachment in senile retinoschisis.
Retinosquise significa uma separação anormal das camadas da retina e, na maioria dos casos, é assintomática. Aumento da área de retinosquise, roturas e descolamento de retina são possíveis complicações da doença, sendo seus tratamentos controversos. Nesse relato, apresentamos um caso de descolamento de retina associado à retinosquise senil em que foi optado pela retinopexia pneumática como primeiro tratamento, com sucesso em um dos olhos tratados. Revisada literatura sobre retinosquises e retinopexia pneumática para tratamento de descolamento de retina associado, foi encontrado apenas um caso tratado com sucesso, sem drenagem de líquido sub-retiniano, utilizando-se ar como agente tamponante. Não existem relatos na literatura de retinopexia pneumática efetiva utilizando C3F8 como tratamento único para descolamento de retina progressivo na retinosquise senil.
Subject(s)
Humans , Male , Middle Aged , Fluorocarbons/therapeutic use , Retinal Detachment/therapy , Retinoschisis/therapy , Disease Progression , Follow-Up Studies , Light Coagulation , Ophthalmologic Surgical Procedures , Retinal Detachment/pathology , Retinoschisis/pathology , Subretinal Fluid , Tomography, Optical Coherence , Treatment FailureABSTRACT
A ruptura do ligamento cruzado cranial (RLCCr) figura entre as principais enfermidades ortopédicas na espécie canina, sendo responsável por instabilidade da articulação do joelho, o que resulta em claudicação e desenvolvimento de doença articular degenerativa (DAD). O objetivo deste trabalho foi avaliar os resultados da técnica de TightRope modificada (TRM) na estabilização do joelho de cães com ruptura do ligamento cruzado cranial (RLCCr). O procedimento cirúrgico foi realizado em seis animais, os quais foram avaliados por 120 dias de pós-operatório. A modificação da técnica para estabilização extra capsular da RLCCr, consiste na utilização de fio de fluorcarbono, e fio de aço inoxidável de 1 mm como forma de fixação óssea. A TRM promoveu a estabilidade do joelho dos pacientes com ruptura do ligamento cruzado cranial no pós-operatório imediato e durante o acompanhamento clínico pós-cirúrgico demonstrou, aos 30 dias, progressiva melhora da marcha e suporte de peso à deambulação, estando todos os animais recuperados clinicamente aos 120 dias de pós-operatório.
Rupture of the cranial cruciate ligament is one of the leading orthopedic diseases in dogs. Thus aimed to evaluate the techniqueof Tightrope modified (TRM) in the knees of dogs with the purpose of providing less invasive and cost-effective surgery. Thesurgical procedure was performed in six animals, and these were evaluated up to 120 days postoperatively. The modification of thetechnique for stabilization of extra capsular CCL consists in using fluorocarbon and the stainless steel wire of 1 mm in order bonefixation. The TRM promoted the stability of the knee of patients diagnosed with cranial cruciate ligament rupture in the immediatepostoperative period. Clinical follow-up after surgery showed after 30 days postoperatively, improved gait and progressive weightsupport for ambulation, being all animals recovered clinically at 120 days postoperatively.
Subject(s)
Animals , Dogs , Carbon Fiber , Fracture Fixation/methods , Fracture Fixation/veterinary , Knee Injuries/surgery , Knee Injuries/veterinaryABSTRACT
Fluorinated denture base acrylic resins can present more stable physical properties when compared with conventional polymers. This study evaluated the incorporation of a fluoroalkyl methacrylate (FMA) mixture in a denture base material and its effect on roughness and flexural strength. A swelling behavior assessment of acrylic resin specimens (n=3, per substance) after 12 h of FMA or methyl methacrylate (MMA) immersion was conducted to determine the solvent properties. Rectangular specimens (n=30) were allocated to three groups, according to the concentration of FMA substituted into the monomer component of a heat-polymerized acrylic resin (Lucitone 550), as follows: 0 percent (control), 10 percent and 20 percent (v/v). Acrylic resin mixed with concentrations of 25 percent or more did not reach the dough stage and was not viable. The surface roughness and flexural strength of the specimens were tested. Variables were analyzed by ANOVA and Tukey's test (a=0.05). Immersion in FMA produced negligible swelling, and MMA produced obvious swelling and dissolution of the specimens. Surface roughness at concentrations of 0 percent, 10 percent and 20 percent were: 0.25 ± 0.04, 0.24 ± 0.04, 0.22 ± 0.03 mm (F=1.78; p=0.189, not significant). Significant differences were found for flexural strength (F=15.92; p<0.001) and modulus of elasticity (F=7.67; p=0.002), with the following results: 96 ± 6, 82 ± 5, 84 ± 6 MPa, and 2,717 ± 79, 2,558 ± 128, 2574 ± 87 MPa, respectively. The solvent properties of FMA against acrylic resin are weak, which would explain why concentrations over 20 percent were not viable. Surface changes were not detected after the incorporation of FMA in the denture base acrylic resin tested. The addition of FMA into denture base resin may lower the flexural strength and modulus of elasticity, regardless of the tested concentration.
Subject(s)
Acrylic Resins/chemistry , Denture Bases , Fluorocarbon Polymers/chemistry , Methacrylates/chemistry , Dental Stress Analysis , Elastic Modulus , Fluorine/chemistry , Materials Testing , Methylmethacrylate , Pliability , Solvents , Surface PropertiesABSTRACT
BACKGROUND: Liquid ventilation is associated with decreased inflammatory response in an injured lung. This study was performed to investigate if whether perfluorocarbon (PFC) can decrease chemokine expression in airway epithelial cells. METHODS : A549 cells were used for airway epithelial cells and perfluorodecalin for PFC. To expose cells to PFC, lower chamber of Transwell a plate was used. This study was performed in two parts. In the first part, we examined whether PFC could decrease chemokine expression in airway epithelial cells through inhibition of other inflammatory cells. Peripheral blood mononuclear cells (PBMC's) were isolated and stimulated with lipopolysaccharide (LPS, 10 mg/mL) for 24 hours with or without exposure to PFC. Then A549 cells were stimulated with conditioned media (CM) containing the culture supernatants of PBMC . After 24 hours, the expressions of interleukin-8 (IL-8) and RANTES were measured. In the second part of the study, we studied whether PFC could directly suppress chemokine expression in airway epithelial cells. A549 cells were stimulated for 24 hours with interleukin-1b and/or tumor necrosis factor-a with or without exposure to PFC (,)and then the chemokine expression was measured. Northern analysis was used to measure the mRNA expression (,) and ELISA was used for immunoreactive protein measurements in culture supernatant. RESULTS: 1. IL-8 and RANTES mRNA expression and immunoreactive protein production were increased significantly by CM from LPS-stimulated PBMC in A459 cells compared with CM from unstimulated PBCM(p<0.05) (,)but exposure of PFC had no significant effect on either mRNA expression immunoreactive protein expression. 2. IL-8 and RANTES mRNA expression and immunoreactive protein production were increased significantly by IL-1b and TNF-a in A549 cells(p<0.05)(,)but exposure of PFC had no significant effect on either mRNA expression or immunoreactive protein production. CONCLUSION: Decreased chemokine expression of airway epithelial cells may not be involved in decreased inflammatory response observed in liquid ventilation. Further studies on possible mechanisms of decreased inflammatory response are warranted.
Subject(s)
Chemokine CCL5 , Culture Media, Conditioned , Enzyme-Linked Immunosorbent Assay , Epithelial Cells , Inflammation , Interleukin-8 , Liquid Ventilation , Lung , Necrosis , RNA, MessengerABSTRACT
The use of resorbable implants has always been attractive to surgeons because there is no need to remove implant ai'ter fracture fixation. Other advantages include decreased load sharing, multi-taskirv ancl no metal toxicity. But the strength and stiffness of resorhable implants are less than those of metallic implants. Therefore, these implants are suitahle for fixation of particular fractwre sites such as cancellous bone and epiphyscs in which shear loads comprise the major strains. The purpose of this experimental study was to determine whether there are changes in mechanical properties and tissue reactions in the polylactic acid (PLA) rod hy surface moditication using plasma coating or hexafluoropropylene (CF3CF=CF2). PLA rods were inserted into the subcutaneous tissue of back and distal femur in rabbits. Rods in subcutaneous tissue were retrieved for material characterization and those in distal femur were ohtained for histologic observation at postoperative 2, 5, 12 and 16 weeks. The results were as follows; 1. The hydrophobicity of PLA surface was successfully ohtained by plasma coating of hexatluoropropylene gas. 2. Thcre is no significant change in tissue reaction. between controi and plasma coating PLA group. 3. The diametral strength and 3-points bending strength of plasma coating groups were higher than those of control group until postoperative 12 wks, but, diminished at postoperative 16 weeks. In conclusion, the plasma coating of PLA rod using fluorocarbon is a reasonable technique to incrcase the surface hydrophohicily and a promising method to delay the reduction of the strength of PLA rod. Further study on thicker plasma coating and Jong term effect including degradation, nsetaholism and excretion of cotated fluorocarhon will be needed.
Subject(s)
Rabbits , Femur , Fracture Fixation , Hydrophobic and Hydrophilic Interactions , Plasma , Subcutaneous TissueABSTRACT
BACKGROUND: Left ventricular contrast echocardiography has been used to evaluate congenital cardiac anomaly, valvular regurgitation, left ventricular wall motion and myocardial perfusion. The contrast agent capable of crossing the pulmonary capillary must be small, stable and echoreflective. METHODS: To make a transpulmonary contrast agent, a mixture of 8 mL of fluorocarbon (C3F8) gas, 5% human serum albumin and 5% dextrose solution was sonicated for 80 seconds. We measured the microbubble size and number of the contrast agent by Coulter counter and hemocytometer. We injected the contrast agent intravenously into the 8 mongrel dogs with systemic arterial blood pressure and heart rate monitoring. The dosage of the contrast agent was various from 0.01 mL/Kg to 0.1 mL/Kg. Echocardiographic examination was done while the contrast agent was injected. Arterial blood gas analysis was done repeatedly before and after contrast agent injection. RESULTS: The microbubble size of the contrast agent was 60.8+/-9.3 fL, and its number was 1.0 x 10 8 /mL. Left ventricular opacification was observed in all cases by intravenous injection of the contrast agent. The minimal dose for the complete opacification of the left ventricle by visual estimation was 0.05 mL/Kg. Hemodynamic variables did not change between pre and post injection of the contrast agent. CONCLUSION: Fluorocarbon based contrast agent could be used intravenously to opacify the left ventricle and it causes no hemodynamic chage in mongrel dogs.
Subject(s)
Animals , Dogs , Humans , Arterial Pressure , Blood Gas Analysis , Capillaries , Echocardiography , Glucose , Heart Rate , Heart Ventricles , Hemodynamics , Injections, Intravenous , Microbubbles , Perfusion , Serum AlbuminABSTRACT
Objective It has been shown that partial liquid ventilation (PLV) with perfluorocarbon (PFC) can reduce intrapulmonary aggregation of neutrophils (PMNs) and macrophages and their cytokine release during acute lung injury (ALI) . The purpose of this study was to investigate the effect of PFC on activation of nuclear factor-kappa B (NF-?B) in neutrophils induced by lipopolysacchride (LPS) .Methods PMNs were isolated from peripheral blood obtained from 36 healthy volunteers and incubated in RPM 1640 cell culture medium yielding a concentration of 1?108/ hole. The PMNs were randomly divided into two groups : (Ⅰ) LPS group in which PMNs were incubated with LPS 10?g?ml-1(n = 18) and (Ⅱ) PFC group in which 5 min after stimulation of PMNs with the same concentration of LPS (10?g?ml-1 ) , PFC was added to the cell suspension with the final concentration of PFC / cell culture medium (vol / vol) of 0.3 (n=18 ). After incubation with LPS for 3 h (T1), 8h (T2) and 24 h (T3), the cell suspensions were centrifuged. The supernatants were analyzed for TNF-? concentration and gray value of activated NF-?B was measured in the nuclear of neutrophils. Results The concentration of TNF-a and gray value of NF-?B in PFC group were significantly lower than those in LPS group at all time points ( P
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Objective To study the efficacy and safety of nanometer perfluorocarbon (PFC) in the treatment of hemorrhagic shock, and its role in protecting cerebral cortex nerve cells.Methods Hemorrhagic shock was induced in New Zealand rabbits by arterial bleeding. In the course of the experiment, heart rate, respiratory rate, blood pressure, blood gases, hepatic and renal function, and pathological changes in cerebral cortex were observed. Results The survival rate of animals in the experimental group at 12 hours was higher than that of control group, respiration was deeper and respiratory rate was faster, blood pressure and PaO 2 were significantly higher than that in animals of the control group. There was a tendency of acidosis in the control group. Pupil reflex was more sensitive in the experimental group, and hepatic and renal functions were better in the experimental group than that in control group. Pathological observation showed the cerebral cortex was less damaged in the treatment group than that in control group. Conclusions Nanometer PFC was effective in combating hemorrhagic shock, showing no toxicity to liver and kidney, and it could also be used as an effective neuroprotective agent.
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Fluorocarbon emulsion, a substitute of blood, 20 ml/kg were injected once into dogs intravenously. As a result, part of the substitute deposited in the lympho-retic-ular system and was phagocytized by fixed and free histiocytes (rnonophagocytic system), and the histiocytes then converted into foaming cells.One month after injection, the fluorocarbon's deposits in the foaming cells remained at the peak level in the liver, spleen and other organs of the lympho-reti-cuJar system. After six months,no deposits could be found in all viscera and no signs of any pathological changes, except the spleen under a light microscope.After twelve months, no foaming cells were found in the spleen, liver, and kidney under light cmicroscope,yet but foaming cells could be found in the spleen and liver with the help of an electron microscope and we believed that this sign had no pathological significance in clinic practice.The target cells only showed the action of phagocitizing and depositing.According to our observation, the fluorocarbon emulsion is a non cytoplasmic toxin and an inert biologic substance, so there are no secondary histo-pathologic changes caused by fluorocarbon deposition. It seems that 20 ml/kg of fluorocarbon emulsion (equal to 1200 ml for adult human)injected intravenously is rather safe.