[Impacts of Anthropogenic Emission Reduction and Meteorological Conditions on PM2.5 Pollution in Typical Cities of Beijing-Tianjin-Hebei in Winter].

This study used sampling analysis and a CAMx-PSAT coupling model to analyze the components, transmission, and source apportionment of PM2.5 in Beijing and Tangshan in January 2018. The results showed that in January 2018, water-soluble inorganic ions (WSⅡs) accounted for 49.59% and 39.13% of PM2.5 mass concentrations in Beijing and Tangshan, respectively. The ratios of NO3- to SO42- were 2.02 and 1.51, respectively, indicating that pollution in both cities was dominated by mobile sources. In Beijing and Tangshan, PM2.5 accounted for 48.74% and 30.67% of transmission, respectively. Regional transmissions were mainly contributed by neighboring areas, northwest masses, and southwest masses. However, the contribution of the southwest passage to pollution in the respective cities increased by 9.65% and 15.02% during pollution periods. The principal sources contributing to PM2.5 pollution in Beijing were mobile and dust sources. Secondary ions were more obviously affected by regional contributions, mobile and industrial sources had the most significant effect in Tangshan, and most particulate matter and sulfate were contributed by local emissions. From 2013 to 2018, the dominant component of WSⅡs changed from sulfate to nitrate while the main pollution sources changed from coal-fired and industrial sources to mobile and dust sources. Meanwhile, in January 2018, the meteorological factors were more favorable for pollution mitigation than in 2013. The meteorological impact of secondary ions is closely related to the lower relative humidity in 2018, compared to 2013.

[Comparison Analysis of the Effect of Emission Reduction Measures for Major Events and Heavy Air Pollution in the Capital].

Taking the "9.3" military parade in 2015 and two red alerts of heavy air pollution in December of the same year as examples, the characteristics of meteorological factors and pollutant concentration variation were compared. Based on the estimation of pollutant emission reduction under different periods, the WRF-CAMx model was used to evaluate the effect of PM2.5 pollution improvement. The results showed that the daily average PM2.5 concentration (19.0 µg·m-3) during the parade (from August 20 to September 4) decreased by 60.0% and 48.0%, respectively, in comparison to that before (August 15-19) and after (September 5-15) the parade. The daily average PM2.5 concentration (232.3 µg·m-3) during the first red alert period was higher than that of the second red alert (216.6 µg·m-3). The air quality before the second red alert was better than that before the first red alert. The proportion of emission reduction during the parade was generally larger than that during the red alert periods, which provided a controllable and favorable condition for the realization of the "Parade Blue". The PM2.5 concentration in Beijing decreased by 32.4%, 17.1%, and 22.0% under the control measures during the periods of the "9.3" parade, the first red alert, and second red alert, respectively. The higher proportion of PM2.5 concentration reduction could be attributed to the more intensive regional emission reduction and the favorable meteorological conditions. The intensity of the pollution reduction, the timing of the implementation of emergency control measures, and meteorological conditions were the most important factors that may have influenced the improvement of pollution.

Clinical efficacy of Ahmed glaucoma valve implantation combined with 23-gauge vitrectomy for medically uncontrolled neovascular glaucoma with proliferative diabetic retinopathy.

AIM: To describe the clinical results of combined Ahmed valve implantation and 23-gauge vitrectomy for medically uncontrolled neovascular glaucoma (NVG) secondary to proliferative diabetic retinopathy (PDR). METHODS: The medical records of medically uncontrolled NVG patients with PDR who underwent Ahmed valve implantation and 23-gauge vitrectomy between March 2016 and December 2018 were reviewed. Enrolled patients had at least 6-month follow-up. Panretinal photocoagulation (PRP), anti-vascular endothelial growth factor, surgery and medication history were documented. RESULTS: Eleven eyes of 11 patients were included in our study. The visual acuity improved in 8 eyes and remained unchanged in 3 eyes. The preoperative intraocular pressure (IOP) was significantly decreased at the last follow-up (48.8±4.3 to 17.0±1.5 mm Hg, P<0.001). All eyes needed three topical anti-glaucomatous medications before surgery, but the number was significantly reduced to 0.72±0.19 at the last visit (P<0.001). Four eyes had choroidal detachment and 3 eyes had minor hyphemia, all of which gradually resolved without treatments in one week. CONCLUSION: Ahmed glaucoma valve implantation combined with 23-gauge vitrectomy might be a safe and alternative treatment for NVG with PDR.

Comparison of canaloplasty and trabeculectomy for open angle glaucoma: a Meta-analysis.

AIM: To evaluate the advantage of canaloplasty compared to trabeculectomy for patients with open angle glaucoma. METHODS: Potentially relevant studies were systematically searched using various databases from inception until December 2015. The outcome analyses performed automatically using Revman 5.3 included intraocular pressure reduction (IOPR), postoperative success rate, anti-glaucoma medications reduction and the incidence of adverse events. RESULTS: We included four qualified studies incorporating a total of 215 eyes for quantitative synthesis. The weighted mean difference (WMD) of IOPR between canaloplasty and trabeculectomy from baseline to 12mo was -2.33 (95%CI: -4.00, -0.66). There was not significant improvement in the complete or qualified success rate (OR: 0.58, 95%CI: 0.26, 1.31; OR: 0.50, 95%CI: 0.10, 2.44, respectively). Similarly, no statistically significance was observed in anti-glaucoma mediations reduction (WMD: -0.54, 95%CI: -1.18, 0.09). Sensitivity analysis of the primary outcome estimate confirmed the stability of the Meta-analysis result. CONCLUSION: Trabeculectomy seems to be more effective in lowering IOP up to 12mo when comparing with canaloplasty. Canaloplasty does not seem to be inferior to trabeculectomy considering the postoperative success rate or the number of postoperative anti-glaucoma medications. Meanwhile, it has an advantage of less bleb related complications.

Effect of adenosine on GLAST expression in the retina of a chronic ocular hypertension rat model.

This study was performed to evaluate the effect of adenosine and an adenosine receptor antagonist on the expression of the L-glutamate/L-aspartate transporter (GLAST) in the retina of a chronic ocular hypertension (COH) rat model. COH models were established via the cauterization of three episcleral veins. Measurements of the intraocular pressure of the right eye (COH eye) were taken weekly by a handheld digital tonometer. A total of 10 µM adenosine or 10 µM adenosine + 100 nM SCH442416 solution (2 µl) was injected into the rat vitreous space. The reverse transcription-quantitative polymerase chain reaction, western blotting and immunohistochemistry were used to detect GLAST expression. Compared with the COH group, GLAST mRNA expression was decreased by 33.6% in the group treated with adenosine (n=6, P=0.020) and was increased by 159.6% in the group treated with SCH442416 (n=6, P=0.001). Administration of adenosine decreased GLAST protein expression by 34.7% (n=6, P<0.001), while treatment with the adenosine A2A receptor antagonist SCH442416 increased GLAST protein expression by 48.3% compared with the control COH group (n=6, P<0.001). Immunohistochemical experiments showed that administration of adenosine decreased GLAST protein expression, as compared with expression in the control COH rat retina. Administration of SCH442416 markedly increased GLAST protein expression. The results of the present study may provide a novel method for retinal neuron protection.

A New Terminal Cyano Group-containing Benzodiazepine Alkaloid from the Mangrove Endophytic Fungus Penicillium sp. .

A new benzodiazepine alkaloid containing terminal cyano group has been isolated from a mangrove endophytic fungus, Penicillium 299#. Structure elucidation was determined by 1D and 2D NMR spectroscopy and the absolute configuration was determined by electronic circular dichroism (ECD). The new compound showed no cytotoxic activities in vitro against human cancer lines MDA-MB-435, HepG2, HCT-116, and Calu-3.

The effect of ROCK-1 activity change on the adhesive and invasive ability of Y79 retinoblastoma cells.

BACKGROUND: Retinoblastoma (Rb) is the most common intraocular tumor in childhood worldwide. It is a deadly pediatric eye cancer. The main cause of death in Rb patients is intracranial and systemic metastasis. ROCK is the main downstream effector of Ras-homologous (Rho) family of GTPases which are involved in many cellular functions, such as cell proliferation, invasion and metastasis. Overexpression of ROCK promotes invasion and metastasis of many solid tumors. However, the effect of ROCK in Rb is largely unknown. METHODS: ROCK-1 and ROCK-2 mRNA expression in Y79 cell lines were examined by RT-PCR. Protein expression in the Y79 cell line were examined by western blot analyses. ROCK-1 and ROCK-2 siRNA were transfected into Y79 cells with Lipofectamine 2000. Cell proliferation was evaluated by CCK-8 assay after exposure to ROCK inhibitor (Y-27632). We examined the effect of ROCK inhibitors (Y-27632, ROCK-1 and ROCK-2 siRNA) on Y79 cell adhesive capacity by cell adhesion assay. Cell invasion assay through matrigel was used to study the effect of ROCK inhibitors on Y79 cell invasive capacity. RESULTS: The expression of mRNA of ROCK-1 was more than that of ROCK-2 in the Y79 cell line. The protein expression levels of ROCK-1 and ROCK-2 were downregulated in the cells transfected with siRNA. Y-27632 treatment didn't lead to any changes of Y79 cells proliferation. Adhesive ability of Y79 cells was enhanced following Y-27632 or ROCK-1 siRNA treatment. The invasive capacity of Y79 cells showed an inverse relationship with increasing Y-27632 concentration. Invasiveness of Y79 cells also decreased in Y79 cells transfected with ROCK-1 siRNA. However, there was no change in adhesive ability or invasive capacity in Y79 cells transfected with siRNA against ROCK-2. CONCLUSIONS: The findings of this study demonstrate that ROCK-1 protein plays a key role in regulating metastasis and invasion of Y79 cells, suggesting that the ROCK-1 dependent pathway may be a potential target for therapy of Rb.

Ahmed valve implantation for neovascular glaucoma after 23-gauge vitrectomy in eyes with proliferative diabetic retinopathy.

AIM: To report on the outcome of Ahmed glaucoma valve (AGV) implantation for the management of neovascular glaucoma (NVG) after 23-gauge vitrectomy for proliferative diabetic retinopathy (PDR). METHODS: Twelve medically uncontrolled NVG with earlier 23-gauge vitrectomy for PDR underwent AGV implantation. The control of intraocular pressure (IOP), preoperative and postoperative best-corrected visual acuity, the development of intraoperative and postoperative complications were evaluated during the follow-up. RESULTS: The mean follow-up was 15.4±4.3 months (9-23 months). Mean preoperative IOP was 49.4±5.1mmHg and mean postoperative IOP at the last visit was 17.5±1.6mmHg. The control of IOP was achieved at the final follow-up visits in all patients, however, 8 of 12 patients still needed anti-glaucoma medication (mean number of medications, 0.8±0.7). The visual acuity improved in nine eyes, and the visual acuity unchanged in three eyes at the final follow-up visits. The complications that occurred were minor hyphema in three eyes, choroid detachment in two eyes, and the minor hyphema and choroid detachments were reabsorbed without any surgical intervention. CONCLUSION: AGV implantation is a safe and effective procedure that enables successful IOP control and vision preservation in the NVG patients with the history of earlier 23-gauge vitrectomy for PDR.

Potassium ion channels in retinal ganglion cells (review).

Retinal ganglion cells (RGCs) consolidate visual processing and constitute the last step prior to the transmission of signals to higher brain centers. RGC death is a major cause of visual impairment in optic neuropathies, including glaucoma, age­related macular degeneration, diabetic retinopathy, uveoretinitis and vitreoretinopathy. Discharge patterns of RGCs are primarily determined by the presence of ion channels. As the most diverse group of ion channels, potassium (K+) channels play key roles in modulating the electrical properties of RGCs. Biochemical, molecular and pharmacological studies have identified a number of K+ channels in RGCs, including inwardly rectifying K+ (Kir), ATP­sensitive K+ (KATP), tandem­pore domain K+ (TASK), voltage­gated K+ (Kv), ether­à­go­go (Eag) and Ca2+­activated K+ (KCa) channels. Kir channels are important in the maintenance of the resting membrane potential and controlling RGC excitability. KATP channels are involved in RGC survival and neuroprotection. TASK channels are hypothesized to contribute to the regulation of resting membrane potentials and firing patterns of RGCs. Kv channels are important regulators of cellular excitability, functioning to modulate the amplitude, duration and frequency of action potentials and subthreshold depolarizations, and are also important in RGC development and protection. Eag channels may contribute to dendritic repolarization during excitatory postsynaptic potentials and to the attenuation of the back propagation of action potentials. KCa channels have been observed to contribute to repetitive firing in RGCs. Considering these important roles of K+ channels in RGCs, the study of K+ channels may be beneficial in elucidating the pathophysiology of RGCs and exploring novel RGC protection strategies.

Effect of Y-27632 on the cultured retinal neurocytes of rats.

AIM: To investigate the effect of Y-27632 on the survival and neurite outgrowth of the cultured retinal neurocytes. METHODS: After the postnatal day 2-3, Sprague-Dawley retinal neurocytes were cultured for 48 hours, the culture media was replaced with serum-free media (control group) and serum-free media contained 30µmol/L Y-27632 (Y-27632 group), and the cells were continually cultured another 48 hours. The cultured retinal neurocytes were identified with anti-neuron specific enolase (NSE) immunocytochemistry. The survival state of those cells was estimated by MTT assay, and the neurite outgrowth of those cells was evaluated by the computerized image-analysis system. RESULTS: Compared with the control group, the absorbance values of cells survival in Y-27632 group increased 12.90% and 33.33% respectively after 72 and 96 hours culture. Y-27632 had no significant effect on the diameter of cultured retinal neurocytes. Compared with the control group, Y-27632 induced a stable improvement of neurite outgrowth of retinal neurocytes after 72 and 96 hours culture (P=0.001). CONCLUSION: Y-27632 could promote the survival and neurite outgrowth of the early postnatal cultured retinal neurocytes.

Evaluation of a partial optic nerve crush model in rats.

This study was performed to determine whether a partial optic nerve crush (PONC) model in rats is effective and reliable for the study of optic nerve protection and regeneration. Bilateral superior colliculus (SC) retrograde 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate (DiI) labeling of retinal ganglion cells (RGCs; n=3) and unilateral SC retrograde labeling of RGCs (n=3) were performed in adult Sprague-Dawley (SD) rats and the results were compared with the bilateral and unilateral SC retrograde-labeled RGCs. Another 40 adult SD rats, three days after bilateral SC retrograde DiI labeling of RGCs underwent crushing with a non-invasive vascular clip (40 gram power) 1 mm behind the right optic nerve head for 5, 10 and 30 sec (n=10 each), and a sham-operated control group (n=10) was used as a control. The retinas of all 40 rats were flattened by four radial cuts, mounted vitreal side-up on gelatin-coated slides, and the number of labeled RGCs was counted in four distinct regions per retinal quadrant at three different eccentricities of 1/6, 3/6 and 5/6 of the retinal radius three days later. Bilateral SC retrograde DiI injection labeled the majority of normal RGCs, while unilateral SC injections only labeled a small part of the RGCs; the majority of RGCs were not labeled. In the mild crush (5 sec) injury group, the bilateral SC retrograde DiI injection labeled the majority of RGCs. The RGC densities at 1/6, 3/6 and 5/6 of the retinal radius showed no significant difference compared with the RGC densities at the corresponding region of the retinal radius in the sham-operated control group (P=0.734, 0.461, 0.273, respectively). In the moderate crush injury (10 sec) group, the number of labeled RGCs was significantly lower compared to that of the sham-operated control group, and the RGC densities at 1/6, 3/6, 5/6 of the retinal radius were significantly lower compared to the RGC densities at the corresponding retinal radius in the sham-operated control group (P<0.001). In the severe crush injury (30 sec) group the number of labeled RGCs was significantly decreased, and the labeled RGCs were not observed in the region at 5/6 of the retinal radius. The RGC densities at 1/6 and 3/6 of the retinal radius were significantly lower compared to the RGC densities at the corresponding retinal radius region in the sham-operated control group (P<0.001). Compared with the mild and severe optic nerve crush injury models, the moderate crush injury model is more suitable for the study of optic nerve damage and regeneration.

Blue-on-yellow perimetry and corneal thickness in patients with ocular hypertension.

AIM: To evaluate the frequency of blue-on-yellow perimetry (B/YP) deficits in ocular hypertension (OHT) patients and to correlate these findings with central corneal thickness (CCT), and to investigate the influence of age, refraction and gender on the B/YP results in OHT patients. METHODS: The B/YP and CCT were checked respectively in 72 OHT patients with normal white-on-white perimetry(W/WP) and normal optic nerve head. The B/YP was tested by Octopus 101 automated perimetry using G2 strategy, while the CCT was checked with DGH-550 ultrasound pachymeter. All patients were chosen randomly one eye for statistical analysis, a binary regression model was used to determine the independent contribution of variables included in the model, and the differences of the intraocular pressure (IOP), CCT, age, refraction and gender between the normal B/YP group and abnormal B/YP group were compared. RESULTS: Forty-nine out of 72 patients with OHT showed normal B/YP results, whereas 23 of 72 patients(31.9%) demonstrated abnormal B/YP results. CCT showed a correlation with the B/YP results (B=-0.038, SE=0.019, P=0.044), whereas none of the IOP, age, refraction and gender was found to be correlated with the B/YP results. The mean CCT in OHT patients with abnormal B/YP group was lower than that with normal B/YP group (t=2.066, P=0.043).There was a significant positive correlation between IOP and CCT (R(2)=0.513, P=0.000). CONCLUSION: The mean CCT in OHT patients with abnormal B/YP results was lower than that with normal B/YP results. There was a significant positive correlation between IOP and CCT in OHT patients. The age, refraction and gender didn't influence the B/YP results in OHT patients.

Rho/ROCK pathway and neural regeneration: a potential therapeutic target for central nervous system and optic nerve damage.

Rho-associated kinase (ROCK) is a serine/threonine kinase and one of the major downstream effectors of the small GTPase RhoA. The Rho/ROCK pathway is closely related to the pathogenesis of several central nervous system (CNS) disorders, and involved in many aspects of neuronal functions including neurite outgrowth and retraction. In the adult CNS, the damaged neuron regeneration is very difficult due to the presence of myelin-associated axon growth inhibitors such as Nogo, myelin-associated glycoprotein (MAG) and oligodendrocyte-myelin glycoprotein (Omgp), etc. The effects of these axon growth inhibitors are reversed by blocking the Rho/ROCK pathway in vitro, and the inhibition of Rho/ROCK pathway can promote axon regeneration and functional recovery in the injured CNS in vivo. In addition, the therapeutic effects of the Rho/ROCK inhibitors have also been demonstrated in some animal models and the Rho/ROCK pathway becomes an attractive target for the development of drugs for treating CNS disorders. In this review, we summarized on the effect of the Rho and the downstream factor ROCK in neural regeneration, and the potential therapeutic effect of Rho/ROCK inhibitors in the survival and axonal regeneration of retinal ganglion cells was also discussed.

Effect of erythropoietin on the survival of retinal neurocytes in culture upon serum withdrawal.

OBJECTIVES: To clarify whether erythropoietin (EPO) could substitute for the serum component in cultured retinal neurocytes suffering from serum withdrawal. METHODS: 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. RESULTS: 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. CONCLUSION: 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.

[Discrimination of anticancer agent action loci at G(2) and M phases by flow cytometry and confocal microscopic imaging].

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.

[Cell cycle arrest at M phase induced by vinblastine in MOLT-4 cells].

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.

Erythropoietin with retrobulbar administration protects retinal ganglion cells from acute elevated intraocular pressure in rats.

OBJECTIVE: The aim of this study was to clarify whether erythropoietin (EPO) with a retrobulbar administration could protect retinal ganglion cells (RGCs) from acute elevated intraocular pressure (IOP). METHODS: The anterior chamber of the right eye was cannulated, and the IOP was raised to 70 mm Hg for a duration of up to 60 min. One thousand (1000) units of recombinant erythropoietin (rhEPO) or vehicle solution was administered a retrobulbar injection immediately after the onset of the acute elevated IOP. After 1 week, RGCs were labeled with a commercially available retrograde tracer applied to the superior colliculi. Densities of surviving RGCs were estimated by counting retrograde-tracer-labeled cells in whole-mounted retinas. The ultrastructural changes of RGCs were observed by transmission electron microscope. Immunocytochemistry was used to detect EPO and erythropoietin receptor (EPOR) expression in the RGCs layer. RESULTS: The acute elevated IOP could result in the loss of RGCs. The number of surviving RGCs per square millimeter in the eyes of the acute elevated IOP + rhEPO retrobulbar injection group was significantly higher than that in the eyes of the acute elevated IOP and acute elevated IOP + vehicle solution retrobulbar injection groups (P < 0.05). The number of the organelles in the RGCs plasm decreased, but some intact mitochondrian still existed in the RGCs plasm in the eyes of the acute elevated IOP + rhEPO retrobulbar injection group. The densities of EPO and EPOR expression of the RGCs layer in the eyes of the acute elevated IOP + rhEPO retrobulbar injection group were significantly higher than that in the eyes of the acute elevated IOP and acute elevated IOP + vehicle solution retrobulbar injection groups (P < 0.01). CONCLUSION: EPO with a retrobulbar administration could protect RGCs from acute elevated IOP.

[Correlation of intra-cellular localization and variations of active caspase-3 to morphology changes in apoptotic MOLT-4 cells induced by X-ray].

BACKGROUND & OBJECTIVE: How pro-caspase-3 activation lead to serial morphology changes during progress of cell apoptosis is unclear. This study was to investigate the variations and intra-localization of active Caspase-3, determine cell morphology changes in apoptotic MOLT-4 cells induced by X-ray, and evaluate their relationship. METHODS: MOLT-4 cells were irradiated by 10 Gy X-ray. Sub G(1)peak method, and DNA fragmentation assay were used to detect variations of DNA in apoptotic cells. Annexin V/PI method was used to determine the cell membrane reversion, and fluorescence labeled inhibitor of Caspases (FLICA) was used to detect the active Caspase-3 in apoptotic cells. Cell morphology and Caspase-3 intra-localization were determined by confocal microscopy. RESULTS: MOLT-4 cells irradiated by 10 Gy X-ray presented classical apoptotic morphology changes such as membrane reversion, and apoptotic body. Caspase-3 was activated after irradiation, and increased remarkably after irradiated for 4 hours. Activated Caspase-3 moved from sub-membrane toward cytoplasm and nucleus. Caspase-3 activity was detected 2 hours earlier than membrane reversion. CONCLUSIONS: Caspase-3 was activated in MOLT-4 cells induced by X-ray, and its intra-localization correlated with the apoptotic morphology changes. The spatial shift of active Caspase-3 in MOLT-4 cells induced by X-ray is one of the mechanisms of apoptosis.