Ultrastructural study of closed macular hole- preliminary application of a novel high magnification module combining with OCT.

BACKGROUND: As a novel high magnification module (HMM) combining with OCT (OCT-HMM) is able to detect the microstructure of retina, we apply it to explore the ultrastructure of the macula after closure of the idiopathic macular hole (IMH) by surgery. METHODS: This is an observational case series study in which patients with full-thickness IMHs who had undergone successful macular closure by vitrectomy and internal limiting membrane peeling and healthy subjects were recruited. After comprehensive ophthalmic examinations, the images of macular area were obtained and collected by professional operators using OCT-HMM. Then images were independently analyzed by 4 masked vitreoretinal specialists. RESULTS: A total of 24 IMH eyes and 42 healthy eyes were examined. HMM images were obtained in 10 IMH eyes. Among them, 4 eyes whose macula closed completely with recovery of photoreceptor layer presented a dark arc nasal to the fovea, oriented to the optic, and the notch of arc faced temporally. Six eyes in which the macula closed incompletely with photoreceptor cells loss revealed a dark ring with uneven bright spots inside. The other 14 eyes failed to obtain clear images by OCT-HMM. The contra lateral eyes of the patients and the healthy subjects' eyes succeeded to obtain the HMM images which displayed evenly grey background thickly covered with tiny bright dots that was in similar size and evenly and widely distributed and there no dark arc or ring. OCT B-scan and IR images could be acquired in all of the IMH and healthy eyes. CONCLUSION: The preliminary application of HMM has supplied us a brand-new insight into the microstructure of closed IMH. A dark arc sign could be detected with OCT-HMM in the macula which was functionally closed after surgery that was probably the healing mark on a microstructure photoreceptors level. Its existence and shape indicated that the functional closure followed by a retinal displacement mainly horizontally from temporal side to nasal side but not symmetric centripetally.

Anticancer effect of docetaxel induces apoptosis of prostate cancer via the cofilin-1 and paxillin signaling pathway.

Prostate cancer is a common multiple malignant tumor occurring in males. Prostate cancer mortality is the 2nd most common of all tumor types in Western countries and the mortality of morbidity is 13% in the USA. The present study aimed to investigate the anticancer effect of docetaxel on inducing the apoptosis of prostate cancer via the cofilin­1 and paxillin signaling pathway. Treatment with docetaxel (1­50 nM) disposed the human LNCaP prostate cancer cells for 24 h. Cell growth and cytotoxicity were subsequently measured using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and lactate dehydrogenase assay, respectively. Docetaxel-induced cell death was analyzed using flow cytometric and caspase-3 assays. Reverse transcription­quantitative polymerase chain reaction analysis was used to detect the gene expression of cofilin­1 and western blots were used to determine the protein expression of paxillin. Treatment with docetaxel inhibited cell growth, promoted cytotoxicity, activated apoptosis and increased caspase­3 activity in the LNCaP cells. Notably, administration of docetaxel reduced the gene expression of cofilin­1 and the protein expression of paxillin in the LNCaP cells. Additionally, knockdown of cofilin­1 advanced the anticancer effect of docetaxel against LNCaP cells through suppression of the paxillin pathway. The present findings demonstrated that the anticancer effect of docetaxel induces the apoptosis of prostate cancer via the suppression of the cofilin­1 and paxillin signaling pathways, which will assist in setting a stage for the clinical treatment of prostate cancer.

Evaluation of Docetaxel-Sensitive and Docetaxel-Resistant Proteomes in PC-3 Cells.

OBJECTIVES: Docetaxel was the first drug with proven survival benefit in men with castration-resistant prostate cancer. Acquired resistance to docetaxel precedes fatality in castration-resistant prostate cancer. The aims of this study were to evaluate docetaxel-sensitive and docetaxel-resistant proteomes in PC-3 cells, and to investigate the molecular mechanism of docetaxel-resistant PC-3 cells. METHODS: Docetaxel-resistant PC-3 cells were developed by docetaxel dose escalation. The global profiling of the protein expression was investigated in docetaxel-sensitive and docetaxel-resistant proteomes in PC-3 cells using 2-dimensional polyacrylamide gel electrophoresis/matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. RESULTS: Forty-nine differential proteins were found in docetaxel-resistant PC-3 cells in comparison with docetaxel-sensitive PC-3 cells. Expression in 29 proteins was upregulated, whereas expression in 20 proteins was downregulated. ATP synthase and galectin-1 were involved in the formation of tumor vessels; calreticulin, cathepsin D, and cofilin were involved in tumor metastasis, and GRP78 (78-kDa glucose-regulated protein) and microtubule-associated protein-6 were involved in drug resistance of tumor. CONCLUSION: It is suggested that a proteomic expression difference exists between docetaxel-sensitive and docetaxel-resistant PC-3 cells, which would be helpful for further understanding the molecular mechanisms of docetaxel resistance in PC-3 cells.

A modified suspension test for estimating the mutagenicity of samples containing free and (or) protein-bound histidine.

The Ames test has not been very effective in estimating the mutagenicity of histidine-containing samples because external free and (or) protein-bound histidine in these samples would allow the histidine auxotrophs in such test samples to grow more compared with the negative controls that were used as the reference. This could give rise to a false positive.n this study, a modified suspension mutagenicity assay (MS assay) was developed. The tester strains were incubated in Luria-Bertani (LB) broth containing different concentrations of traditional Chinese medicines (TCMs) until the declining phase, and the test samples were assayed to be mutagenic or not by observing whether statistically significant differences were demonstrated in the relative reversion frequencies (RRFs) between the negative control groups and the test groups. Collectively, using LB broth as the test medium and comparing the RRFs in the declining phase made this assay less influenced by the presence of histidine in the test samples.The mutagenicity of some TCMs was measured with the MS assay. The results in MS assay were consistent with those in the mammalian bone marrow chromosomal aberration test, which indicated that the MS assay was appropriate to estimate the mutagenicity of samples containing free and (or) protein-bound histidine.

[Toxic effects of HSV-TK and CD-TK suicidal gene systems on prostate carcinoma cells].

BACKGROUND & OBJECTIVE: Suicidal gene therapy is one of promising gene therapies. In order to assess the value of suicidal gene therapy on human prostate carcinoma, the authors studied the toxic effects of HSV-TK gene and CD-TK fusion gene systems on prostate carcinoma cell line PC-3m. METHODS: HSV-TK gene and CD-TK fusion gene were separately transfected into PC-3m cells through retrovirus vectors. Reverse transcription-polymerase chain reaction (RT-PCR) was used to demonstrate successful transfection and transcription of suicidal genes. The toxic effects of GCV, 5-FC, and both of them on transfected PC-3m cells were explored by MTT assay; non-transfected PC-3m cells were used as control. RESULTS: Significantly cytotoxic activity of GCV was observed and 50% inhibitory concentration(IC(50)) was 8.34 microg/ml,the bystander effect of GCV was modest,while the bystander effect of 5-Fc was significant,it began to show when the percent of tansfected PC-3m cells in mixed cells was 5%. Simultaneous treatment with two prodrugs on CD-TK expressing cells resulted in additive or synergistic toxicity,coefficient of drug interaction(CDI) was under 1. CONCLUSION: CD-TK fusion suicidal gene system has significant toxic effect on PC-3m cells in vitro, which was superior to HSV-TK alone gene system.

Morphologies and phylogenetic classification of cellulolytic myxobacteria.

The evolutionary distances of the 16S rDNA sequences in cellulolytic myxobacteria are less than 3%, which units all the strains into a single genus, Sorangium. The size of myxospores and the shape of sporangioles, rather than fruiting body colors or swarm morphologies are consistent with the changes of the 16S rDNA sequences. It is suggested that there are at least two species in the genus Sorangium: one includes strains with small myxospores and spherical sporangioles, and the color of the fruiting bodies is normally orange or brown, though sometimes yellow or black. The second species has large myxospores, polyhedral sporangioles with many inter-cystic substrates, and normally deep brown to black color.