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?In allusion to the training requirements of eight-year program medical students, combining with our own experience in teaching this type of the students in ophthalmology, we have done some thinking about the training methods of eight-year program medical students in order to improving their comprehensive abilities of ophthalmology. Several suggestions are made in various aspects, including the study of the basic theory of ophthalmology, the training of doctor - patient communication skills, the training of basic clinical skills, the interest developments in ophthalmology subspecialty areas and the training of basic experiment skills.
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Adenosine is an important biological substance in the body. It exists extensively in intracellular and extracellular tissues. In physiological condition, adenosine remains at very low level intissue. However, under stress such as inflammation, ischemia, hypoxia, trauma, or pain etc. the adenosine concentrationwill be elevated dramatically,indicating that adenosine participates in multiple histopathological processes. Adenosine is a natural chemical messenger that binds to four subtypes( A1, A2A, A2B, A3 ) of adenosine receptors and by that, it regulates multiple kinds of physiological functions. Studies found that adenosine plays an important role in the central nervous system, cardiovascular system and coagulation system. In recent years, adenosine has been seen as an attractive option to improve the treatment of glaucoma and retinal diseases. The effects of adenosine in ophthalmology were as follows: adjusting intraocular pressure, inhibiting retinal angiogenesis, dilating retinal blood vessels, regulating retinal nerve conduction, protecting retinal photoreceptors and ganglion cells, arresting the inflammatory response. This article discusses the research progress in adenosine and its receptors as well as biological products of adenosine and projects the application of adenosine in ophthalmology.
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To clarify whether erythropoietin [EPO] could substitute for the serum component in cultured retinal neurocytes suffering from serum withdrawal. The study was performed in the Shanghai Institute of Traumatology and Orthopedics, Shanghai, China between April 2008 and March 2009. A total of 160 postnatal 2-3 day-old Sprague-Dawley rats were used for this study. After the retinal neurocytes were cultured for 48 hours, the culture media was replaced with serum-free media, and the cells were exposed to 1 U/ml, 3 U/ml, and 6 U/ml EPO for another 24 or 48 hours, the cell body diameter was then assessed using a computerized image-analysis system, and the survival and apoptosis rates of those cells were estimated by method of transcription and translation assay and flow cytometry. Immunocytochemistry was used to detect EPO and erythropoietin receptor [EPOR] expression. The retinal neurocytes had obvious EPO/EPOR expression. The early [p=0.002] and total [p=0.049] apoptosis rates of retinal neurocytes cultured with serum withdrawal were significantly higher than that of neurocytes cultured with serum, and the cell viability of neurocytes cultured with serum withdrawal was significantly lower than that of neurocytes cultured with serum [p=0.047]. The EPO had no effect on the cell body diameter of cultured retinal neurocytes. The cell viability and the apoptosis rates of retinal neurocytes were not significantly different from that of simple serum-withdrawal culture at any EPO concentration. As the addition of EPO immediately after serum withdrawal had no effect in preventing retinal neurocytes apoptosis induced by serum withdrawal, EPO cannot substitute for the serum component
Subject(s)
Animals, Laboratory , Retina , Retinal Neurons , Rats, Sprague-Dawley , NeuronsABSTRACT
This study was purposed to evaluate a method to discriminate the action loci of anticancer agents in G(2) and M phases of cell cycle. The meta-amsacrine (m-AMSA) and vinblastine (VBL), already known as G(2) and M phase arrest agent respectively, were used to induce the arrest of MOLT-4 cells at G(2) and M phases, the change of DNA content was detected by flow cytometry, the morphology of arrested cells was observed by confocal microscopy so as to find the arrest efficacy difference of 2 anticancer agents. As a result, the flow cytometric detection showed that the arrested MOLT-4 cells displayed the raise of peaks in G(2) and M phases, but flow cytometric detection alone can not discriminate the difference between them. The observation with confocal microscopy showed that the MOLT-4 cells arrested by m-AMSA displayed the morphologic features in G(2) phase, while the MOLT-4 cells arrested by VBL displayed the morphologic features in M phase. This observation with confocal microscopy is helpful to discriminate the difference between them. In conclusion, the combination of flow cytometry with confocal microscopy is one of the effective methods to discriminate the kind of G(2) or M phase arresting agent of anticancer drugs.
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Humans , Antineoplastic Agents , Pharmacology , Cell Cycle , Cell Division , Flow Cytometry , G2 Phase , Microscopy, Confocal , Tumor Cells, CulturedABSTRACT
This study was purposed to investigate the biological effect of vinblastine (VLS), usually known as inductor of mitotic arrest, on MOLT-4 of ALL cells and to evaluate its significance. The cell arrest in M phase and/or cell apoptosis were induced by treatment of MOLT-4 cells with 0.05 microg/ml VLS for 0 - 12 hours; the DNA histogram was detected by flow cytometry; the morphological changes of cells were observed by confocal microscopy; the cell cycle distribution, cell apoptosis and morphological changes of cells before and after arrest were analyzed by using arrest increasing rate (AIR), arrest efficiency (AE), apoptosis rate (AR) and morphologic parameters respectively. The results indicated that the cell arrest did not accompanied by significant increase of apoptosis rate; the DNA histogram of cell arrest showed dynamic change of cell cycle in time-dependent manner; the arrest efficiency could be quantified. The cell arrest at M phase was accompanied by cell stack in S phase, the cell proliferation rate dropped after cell arrest occurred. The cells arrested at M phase possessed of characteristic morphologic features in cell mitosis. It is concluded that the vinblastine can solely induce arrest of MOLT-4 cells at M phase. This study provides experimental basis for further investigating the relation of cell cycle arrest to apoptosis, mechanism of checkpoint and development of new anticancer drugs.
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Humans , Apoptosis , Cell Cycle , Cell Division , Flow Cytometry , Tumor Cells, Cultured , Vinblastine , PharmacologyABSTRACT
Objective To observe the protective effect of Erigeron Breviscapus(Vant.)Hand-Mazz(EBHM) on retinal ganglion cells(RGCs) and optic nerve in rabbits with elevated intraocular pressure(IOP). Methods Twenty rabbits with chronic elevated IOP were divided into two groups randomly: EBHM treated group(the ocular hypertension with EBHM treated subgroup and the normal IOP with EBHM treated subgroup) and untreated group(the simple ocular hypertension subgroup and the simple normal IOP subgroup). EBHM was irrigated into the stomachs to the treated group after IOP elevated continuously for 7 d.For light and electron microscopy studies,the rabbits' eyes were made into eyeball samples and optic nerve samples after 60 d.The density of RGCs,thickness of retinal nerve fiber layer(RNFL),and optic nerve axons were observed and quantitated by computer image analysis system.The ultra-microstructure changes of RGCs and optic nerve axons were observed by electron microscope.Results(①The RNFL) thickness,RGCs density and number of axons of the two ocular hypertension subgroups were decreased,compared with those of the two normal IOP subgroups(P
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Objective To investigate whether erythropoietin(Epo) is potentially beneficial in protecting cultured retinal neurocytes.Methods Primary isolated retinal nerve cells were cultured.Expressions of Epo and EpoR protein in cultured retinal neurocytes were decected by immunohistochemical analysis.Survival of cultured neurocytes that were incubated in the presence of Epo or glutamate in the presence or absence of Epo were estimated by determining the activity of their mitochondrial dehydrogenases using the MTT assay.Results Epo and EpoR protein were expressed on the cultured retinal neurocytes.The presence of different concentrations of Epo did not improve the survival of retinal neurocytes,and Epo could prevent glutamateinduced toxicity. Conclusion Epo is beneficial in protecting mixed cultured retinal neurocytes from glutamate-induced cytotoxicity.
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0.05).The recurrence of pterygium was related to the age.If the age increased five years,the risk of recurrence decreased 18.1%. Conclusion The application of MMC(during) the operation could decrease the recurrence rate of pterygium.The recurrence rate of pterygium was not related to the time of application of 0.02% MMC,and detainment for 3 min was enough during the operation.
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Objective To explore the effect of interferon-?(IFN-?)on phenotypic transition of human Tenon’s conjunctival capsular fibroblast(HTCF). Methods Cultured HTCF derived from 4 operated human cataracts was induced for 48 hours in absence or presence of IFN-? and/or transforming growth factor-?1(TGF-?1). Then immunocytochemistry and Western blot technology were used to detect the ?-smooth muscle actin(?-SMA)expression and identificate the cell phenotype. Results In contrast to normal HTCF, IFN-?(10 ng/mL) inhibited the expression of ?-SMA(P