RESUMEN
Autophagy is a membrane-mediated degradation process of macromolecule recycling. Although the formation of double-membrane degradation vesicles (autophagosomes) is known to have a central role in autophagy, the mechanism underlying this process remains elusive. The serine/threonine kinase Atg1 has a key role in the induction of autophagy. In this study, we show that overexpression of Drosophila Atg1 promotes the phosphorylation-dependent activation of the actin-associated motor protein myosin II. A novel myosin light chain kinase (MLCK)-like protein, Spaghetti-squash activator (Sqa), was identified as a link between Atg1 and actomyosin activation. Sqa interacts with Atg1 through its kinase domain and is a substrate of Atg1. Significantly, myosin II inhibition or depletion of Sqa compromised the formation of autophagosomes under starvation conditions. In mammalian cells, we found that the Sqa mammalian homologue zipper-interacting protein kinase (ZIPK) and myosin II had a critical role in the regulation of starvation-induced autophagy and mammalian Atg9 (mAtg9) trafficking when cells were deprived of nutrients. Our findings provide evidence of a link between Atg1 and the control of Atg9-mediated autophagosome formation through the myosin II motor protein.
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Autofagia/fisiología , Proteínas de Drosophila/fisiología , Miosina Tipo II/metabolismo , Fagosomas/metabolismo , Proteínas Serina-Treonina Quinasas/fisiología , Inanición/metabolismo , Animales , Animales Modificados Genéticamente , Autofagia/genética , Homólogo de la Proteína 1 Relacionada con la Autofagia , Proteínas Relacionadas con la Autofagia , Células Cultivadas , Drosophila/genética , Drosophila/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Expresión Génica/fisiología , Humanos , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Proteínas de la Membrana/fisiología , Quinasa de Cadena Ligera de Miosina/genética , Quinasa de Cadena Ligera de Miosina/metabolismo , Quinasa de Cadena Ligera de Miosina/fisiología , Fosforilación , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Inanición/genética , Distribución TisularRESUMEN
In relation to dietary Na(+) intake and aldosterone levels, collecting duct principal cells are exposed to large variations in Na(+) transport. In these cells, Na(+) crosses the apical membrane via epithelial Na(+) channels (ENaC) and is extruded into the interstitium by Na,K-ATPase. The activity of ENaC and Na,K-ATPase must be highly coordinated to accommodate variations in Na(+) transport and minimize fluctuations in intracellular Na(+) concentration. We hypothesized that, independent of hormonal stimulus, cross-talk between ENaC and Na,K-ATPase coordinates Na(+) transport across apical and basolateral membranes. By varying Na(+) intake in aldosterone-clamped rats and overexpressing γ-ENaC or modulating apical Na(+) availability in cultured mouse collecting duct cells, enhanced apical Na(+) entry invariably led to increased basolateral Na,K-ATPase expression and activity. In cultured collecting duct cells, enhanced apical Na(+) entry increased the basolateral cell surface expression of Na,K-ATPase by inhibiting p38 kinase-mediated endocytosis of Na,K-ATPase. Our results reveal a new role for p38 kinase in mediating cross-talk between apical Na(+) entry via ENaC and its basolateral exit via Na,K-ATPase, which may allow principal cells to maintain intracellular Na(+) concentrations within narrow limits.
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Canales Epiteliales de Sodio/fisiología , Túbulos Renales Colectores/metabolismo , Sistema de Señalización de MAP Quinasas/fisiología , ATPasa Intercambiadora de Sodio-Potasio/fisiología , Sodio/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/fisiología , Proteínas Quinasas Activadas por AMP/fisiología , Aldosterona/fisiología , Animales , Membrana Basal/metabolismo , Transporte Biológico Activo/fisiología , Línea Celular Transformada , Membrana Celular/metabolismo , Polaridad Celular , Endocitosis/fisiología , Inducción Enzimática , Canales Epiteliales de Sodio/biosíntesis , Canales Epiteliales de Sodio/genética , Homeostasis/fisiología , Líquido Intracelular/metabolismo , Transporte Iónico/fisiología , Túbulos Renales Colectores/citología , Lisosomas/metabolismo , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Masculino , Ratones , Ratas , Ratas Sprague-Dawley , ATPasa Intercambiadora de Sodio-Potasio/biosíntesis , ATPasa Intercambiadora de Sodio-Potasio/genética , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/antagonistas & inhibidoresRESUMEN
Two new marine-derived caryophyllene-type sesquiterpenoids, rumphellols A and B (1 and 2), were obtained from the gorgonian coral, Rumphella antipathies, collected off the waters of Taiwan. Although caryophyllene-type sesquiterpenes are rarely found in marine organisms, compounds of this type could be principal components of R. antipathies. The structures of new Compounds 1 and 2 were determined by analysis of their spectroscopic data, including 1D and 2D NMR experiments. Caryophyllene 1 and 2 were evaluated in terms of their anti-inflammatory activity by examining their inhibitory effects on the generation of superoxide anions and the release of elastase by human neutrophils.
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Antozoos/química , Antiinflamatorios no Esteroideos/química , Extractos Celulares/química , Sesquiterpenos/química , Sesterterpenos/química , Animales , Antiinflamatorios no Esteroideos/farmacología , Extractos Celulares/farmacología , Humanos , Neutrófilos/efectos de los fármacos , Neutrófilos/enzimología , Elastasa Pancreática/metabolismo , Sesquiterpenos Policíclicos , Sesquiterpenos/farmacología , Sesterterpenos/farmacología , Superóxidos/metabolismoRESUMEN
BACKGROUND: The disproportionate distribution of arable land and water resources has become a bottleneck for guaranteeing food security in China. Virtual water and virtual water trade theory have provided a potential solution to improve water resources management in agriculture and alleviate water crises in water-scarce regions. The present study evaluates the green and blue virtual water content of wheat, maize and rice at the regional scale in China. It then assesses the water-saving benefits of virtual water flows related to the transfer of the three crops between regions. RESULTS: The national average virtual water content of wheat, maize and rice were 1071 m(3) per ton (50.98% green water, 49.02% blue water ), 830 m(3) per ton (76.27% green water, 23.73% blue water) and 1294 m(3) per ton (61.90% green water, 38.10% blue water), respectively. With the regional transfer of wheat, maize and rice, virtual water flows reached 30.08 Gm(3) (59.91% green water, 40.09% blue water). Meanwhile, China saved 11.47 Gm(3) green water, while it consumed 7.84 Gm(3) more blue water than with a no-grain transfer scenario in 2009. CONCLUSION: In order to guarantee food security in China, the government should improve water productivity (reduce virtual water content of crops) during the grain production process. Meanwhile, under the preconditions of economic feasibility and land-water resources availability, China should guarantee the grain-sown area in southern regions for taking full advantage of green water resources and to alleviate the pressure on water resources.
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Agricultura/métodos , Conservación de los Recursos Naturales , Oryza/metabolismo , Triticum/metabolismo , Abastecimiento de Agua , Agua/metabolismo , Zea mays/metabolismo , China , Abastecimiento de AlimentosRESUMEN
OBJECTIVE: To discuss the distribution characteristics of language areas in Chinese-English non-fluent late bilinguals. METHODS: Six Chinese-English bilinguals with eloquent tumors underwent awake-surgeries. The activated areas of BOLD-fMRI were obtained as the patients performed pure naming, verb generation, and abstract/concrete judgment tasks. Direct cortical stimulation(DCS) as the golden standard of language mapping were performed during awake-surgeries on the exposed cortical areas. BOLD-fMRI results of 3 language tasks were compared with DCS results. The statistical method was McNemer. RESULTS: Sixteen positive sites(22.5%) were comfirmed out of 71 stimulations. There were 3 specific language sites, in which 2 sites were specific English sites and 1 site was specific Chinese site. When activated areas of BOLD-fMRI were compared with the DCS results, verb generation task had the highest concordance rate 40.9% (95%CI:30.2%-52.5%) . There were significant differences between the results of BOLD-fMRI and DCS of all 3 bilingual tasks(P < 0.017). CONCLUSIONS: There are specific language areas in Chinese-English non-fluent late bilinguals. The BOLD-fMRI language mapping could not substitute DCS in the context of mapping language areas in bilinguals.
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Mapeo Encefálico , Neoplasias Encefálicas/cirugía , Corteza Cerebral/fisiología , Multilingüismo , Adulto , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Adulto JovenRESUMEN
Amorpha fruticosa and Amygdalus pedunculata are common plant species used for greening construction in arid and semi-arid region of Northwest China. In order to explore the feasibility of greening construction and ecological restoration by A. fruticose with A. pedunculata, we exami-ned the allelopathic effects of five concentrations of aqueous leaf extracts of A. fruticosa (0.025, 0.05, 0.10, 0.15 and 0.20 g·mL-1) on eight A. pedunculata varieties (YY1, YY3, YY4, YY5, YY6, SM6, SM7 and SM8), using the methods of paper-petri dish and soilless culture. The results showed that when the concentration of A. fruticosa leaf extracts were 0.025 and 0.05 g·mL-1, the seed germination and seedling growth of YY1 and SM6 were significantly better than other varieties. With increasing concentration of A. fruticosa leaf extracts, the catalase activity of A. pedunculata seedlings first increased and then decreased. The activities of peroxidase and superoxide dismutase, and the contents of soluble protein and chlorophyll showed a downward trend, while the contents of malondialdehyde and soluble sugar and the permeability of cell membrane gradually increased. Results of the principal component and cluster analysis showed that the growth potential of A. pedunculata decreased with the order of YY1, SM6, SM8, SM7, YY6, YY3, YY5 and YY4 under the allelopathic effect of A. fruticose. In conclusion, the artificial collocation and mixed planting of low-density of A. fruticosa with YY1 and SM6 were beneficial to seed germination and seedling growth of A. pedunculata.
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Fabaceae , Thoracica , Animales , China , Germinación , Extractos Vegetales , Plantones , SemillasRESUMEN
Symbiosomes are specific intracellular membrane-bound vacuoles containing microalgae in a mutualistic Cnidaria (host)-dinoflagellate (symbiont) association. The symbiosome membrane is originally derived from host plasma membranes during phagocytosis of the symbiont; however, its molecular components and functions are not clear. In order to investigate the protein components of the symbiosome membranes, homogenous symbiosomes were isolated from the sea anemone Aiptasia pulchella and their purities and membrane intactness examined by Western blot analysis for host contaminants and microscopic analysis using various fluorescent probes, respectively. Pure and intact symbiosomes were then subjected to biotinylation by a cell impermeant agent (Biotin-XX sulfosuccinimidyl ester) to label membrane surface proteins. The biotinylated proteins, both Triton X-100 soluble and insoluble fractions, were subjected to 2-D SDS-PAGE and identified by MS using an LC-nano-ESI-MS/MS. A total of 17 proteins were identified. Based on their different subcellular origins and functional categories, it indicates that symbiosome membranes serve as the interface for interaction between host and symbiont by fulfilling several crucial cellular functions such as those of membrane receptors/cell recognition, cytoskeletal remodeling, ATP synthesis/proton homeostasis, transporters, stress responses/chaperones, and anti-apoptosis. The results of proteomic analysis not only indicate the molecular identity of the symbiosome membrane, but also provide insight into the possible role of symbiosome membranes during the endosymbiotic association.
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Cnidarios/metabolismo , Dinoflagelados/metabolismo , Membranas Intracelulares/metabolismo , Proteínas de la Membrana/metabolismo , Orgánulos/metabolismo , Proteómica/métodos , Simbiosis , Animales , Biotinilación , Electroforesis en Gel de Poliacrilamida , Colorantes Fluorescentes/metabolismo , Espectrometría de Masas , Proteínas de la Membrana/química , Proteoma/química , Proteoma/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Fracciones Subcelulares/metabolismoRESUMEN
OBJECTIVE: To survey birth defects of neonates conceived by using various types of in vitro fertilization and embryo transfer (IVF-ET) between 1998 and 2007 in Shanghai. METHODS: From 1998 to 2007, 8507 neonates from 6551 pregnancies conceived through assistant reproductive technology (ART) from 7 reproductive medicine center in Shanghai were enrolled in this retrospective study, including Shanghai Ji-Ai Genetics and IVF Institute, Shanghai Jiaotong University School of Medicine affiliated Renji Hospital, Ruijin Hospital, China Welfare Institute International Maternal and Infant Health Hospital, Shanghai First Maternity and Infant Health Hospital, Shanghai the Ninth People's Hospital and the Second Military Medical University affiliated Changhai Hospital. The clinical data about the type and incidence of birth defect were analyzed. Meanwhile, the factors associated with birth defect were investigated, such as various ART, gender, mother age, numbers of gestational sac, the source and quality of sperm. RESULTS: The birth defect rate was 1.08% (92/8507) and the most remarkable malformation occurred in circulation system [34% (31/92)]. The rates of major congenital malformations were 1.21% (34/2799) in fresh conventional IVF-ET, 1.07% (20/1871) in IVF-frozen-thawed embryo transfer (IVF-FET), 1.04% (23/2212) in fresh intracyto plasmic sperm injection (ICSI)-ET and 0.92% (15/1625) in ICSI-FET, which did not show statistical difference (P > 0.05). There was also no significantly different incidence of malformations between 1.12% (49/4371) in male neonates and 1.02% (42/4136) in female neonates (P > 0.05). However, the occurrence of congenital malformation is positively related with maternal age, the rates were 0.84%(41/4884) in mother's age less than 30 years and 1.77% (16/902) in mother' age more than 35 years, which reached statistical difference (P < 0.05). It also showed remarkable different incidence among 0.53% (25/4679) in singletons, 1.59% (57/3576) in twins and 3.97% (10/252) in triplets (P < 0.05). No remarkable difference of malformation rate among sperm sources used in fertilization were observed, including 1.09% (81/7419) in ejaculated sperm, 1.21% (7/579) in percutaneous epididymal aspiration (PESA) and 0.79% (4/509) in donor sperm (P > 0.05). CONCLUSIONS: The overall incidence of birth defect in neonates from ART is similar to those conceived naturally and is not associated with different types of IVF-ET, embryo cryopreservation, sperm sources. However, maternal age and multiple pregnancies confer the higher possibility of birth defect.
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Anomalías Congénitas/epidemiología , Transferencia de Embrión , Fertilización In Vitro/efectos adversos , Inyecciones de Esperma Intracitoplasmáticas/efectos adversos , Anomalías Múltiples/epidemiología , Anomalías Múltiples/etiología , Adulto , Factores de Edad , China/epidemiología , Anomalías Congénitas/etiología , Criopreservación , Femenino , Humanos , Incidencia , Lactante , Recién Nacido , Masculino , Embarazo , Embarazo Múltiple , Estudios Retrospectivos , Factores de RiesgoRESUMEN
The present study was aimed to analyze the immunogenicity of recombinant human zona pellucida-3 peptides (r-huZP3a(22 approximately 176) and r-huZP3b(177 approximately 348)) expressed in E. coli through immunizing rabbits, and to evaluate the efficacy of their polyclonal antisera against r-huZP3a(22 approximately 176) and r-huZP3b(177 approximately 348) to inhibit in vitro human sperm-egg binding respectively. Male New Zealand rabbits were immunized using r-huZP3a(22 approximately 176) or r-huZP3b(177 approximately 348) as antigen respectively, which was purified through an improved method of preparative gel polyacryulamide gel electrophoresis. The antibody response level of r-huZP3a(22 approximately 176) or r-huZP3b(177 approximately 348) immunogen in rabbits was determined by ELISA using mouse ZP3-5 (amino acid sequence(137 approximately 150) being completely conserved with huZP3(138 approximately 151) sequence) and specific huZP3-14 (amino acid sequence(327 approximately 340)) synthetic peptides as coating antigens respectively. The immunoreactivity and specificity of the anti-r-huZP3a(22 approximately 176) and anti-r-huZP3b(177 approximately 348) antisera with each r-huZP3 peptides, were tested by immunoblot and immunohistochemistry (using native huZP and human ovary section) respectively. A competitive hemizona assay (HZA) was used to evaluate the efficacy of the antisera against r-huZP3a(22 approximately 176) and r-huZP3b(177 approximately 348) to inhibit in vitro human sperm-egg binding. Both r-huZP3 peptides were able to induce higher antibody titers in rabbits. Each antiserum could specifically recognize or bind to each target r-huZP3 peptide expressed in E. coli and native human ZP in vitro. The antisera also inhibited sperm-egg binding in the HZA. These results show that r-huZP3a(22 approximately 176) and r-huZP3b(177 approximately 348) are of strong immunogenicity. They can be used to develop a kit for detecting whether there are autoantibodies to zona pellucida in unexplained infertile women, and their antisera might be useful tools for determining minimal B-cell epitope sequences of several known huZP3 epitope peptides.
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Proteínas del Huevo/biosíntesis , Proteínas del Huevo/inmunología , Sueros Inmunes/inmunología , Glicoproteínas de Membrana/biosíntesis , Glicoproteínas de Membrana/inmunología , Receptores de Superficie Celular/biosíntesis , Receptores de Superficie Celular/inmunología , Proteínas Recombinantes/inmunología , Interacciones Espermatozoide-Óvulo/inmunología , Animales , Proteínas del Huevo/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Femenino , Humanos , Inmunización , Masculino , Glicoproteínas de Membrana/genética , Conejos , Receptores de Superficie Celular/genética , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/genética , Glicoproteínas de la Zona PelúcidaRESUMEN
Human sperm-egg recognition, adhesion and fusion are key steps in the whole reproductive process. Some abnormalities in human gamete interaction have been shown to be due to defects in the sperm, others attributed to defects in the zona pellucida (ZP) and the egg plasma membrane. This paper reviews the molecular basis and molecular mechanisms of human sperm-egg interaction. More and more advances in the studies of these aspects are shown to be of significant value to the diagnosis and treatment of infertility as well as to the development of assisted reproductive techniques.
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Infertilidad Masculina/fisiopatología , Interacciones Espermatozoide-Óvulo/fisiología , Reacción Acrosómica/fisiología , Femenino , Humanos , Masculino , Zona PelúcidaRESUMEN
The contents of 10 trace elements in edible cactus were determined by air-acetylene flame atomic absorption spectrometry. The sample was dissolved by ashing method. The experiment conditions were optimized by preparing mixed standard solution of these elements and adding LaCl3 and CsCl for interfering complements. The results show that the contents of following elements in the cactus are: 13-47 mg x g(-1) for Mg, K and Ca; 108-243 microg x g(-1) for Zn, Mn, Fe and Na; 34.8 microg x g(-1) for Cu, and 9.8-11.7 micro x g(-1) for Ni, Sr; and the contents of Mg, K, Ca, Zn, Mn, Fe, Na and Cu are higher than those in carrot.
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Hepatic cancer is a class of cancer that is relatively insensitive to chemotherapy, and cancers that harbor EGFR active mutations are more sensitive to EGFR-TK inhibitor such as gefitinib, which becomes the first-line treatment of this subtype of cancer. However, almost all patients treated with gefitinib will develop drug resistance. Here we show that a protein called integrin beta-8 (ITGB8) when over-expressed, is correlated with the gefitinib resistance of hepatic cancer cell line HepG2/G. After ITGB8 silencing, the drug resistance is reversed as the cell proliferation decreases and apoptosis rate increases significantly by gefitinib treatment when compared to HepG2/G. We demonstrated that multi-drug resistant proteins ABCB1, ABCC2 and ABCG2, anti-apoptosis proteins like survivin and Bcl-2, and cycle promoting protein CDK1 are involved in drug resistance of HepG2/G. Other drug-resistance relative proteins like SOD, GST, TS and HIF-1 are also modulated by ITGB8 silencing, but their role in this gefitinib resistance might be indirect. TGF beta pathway could be a critical pathway by which ITGB8 modulates the sensitivity of HepG2/G to gefitinib.
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The soil water storage, growth development, biomass and yield in maize/soybean intercropping system under different separation methods were measured to analyze the resource competition of the intercropping crops. The treatments included no shoot or root separation (T1), shoot and root separation (T2), only root separation (T3), and only shoot separation (T4). Results indicated that compared to others, the average soil moisture content in the 0-120 cm soil layer decreased by 3.1%-12.9% in maize line, and by 2.8%-12.5% in soybean line for T1. Compared to T1, maize growth stage in T2, T3 and T4 came late, and the plant height, leaf area and cumulative total biomass, yield and yield components all decreased, while the trends found for soybean were the opposite. In summary, the changes of crop growth and yield in the maize/soybean intercropping system were driven by the interactions of above- and below-ground parts, and the below-ground part played a more important role.
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Agricultura/métodos , Glycine max/crecimiento & desarrollo , Zea mays/crecimiento & desarrollo , Biomasa , Productos Agrícolas/crecimiento & desarrollo , Raíces de Plantas , Suelo/química , AguaRESUMEN
Objective@#To explore the status of PM 2.5 pollution in school classrooms and the student exposure level, and to provide basic data to safeguard the health of students.@*Methods@#This study continuously monitored the PM 2.5 levels of 16 naturally ventilated classrooms in eight primary and secondary schools in Jiamusi for one academic year using an online environmental monitoring instrument. At the same time, outdoor PM 2.5 data was captured for comparative research, and student exposure to PM 2.5 during school hours was evaluated.@*Results@#The average concentration of PM 2.5 in the classroom in the spring and autumn semesters was (26.93±24.7) and (31.85±30.37)μg/m 3, respectively, and the indoor/outdoor ratio ( I/O ) was 0.92 and 0.95, respectively, which indicated a strong correlation between them. The daily average concentration of all classrooms during both semesters was ( 28.93 ±26.85)μg/m 3, which was slightly higher than the average concentration of (27.53±26.53)μg/m 3 during the daytime when students were in school. In addition, the concentration on workdays was higher than that observed on weekends, and this was termed the "weekend effect". The indoor PM 2.5 concentration was lower on higher floors. The comprehensive exposure concentration of students during school was 28.48 μg/m 3 in spring semester and 31.87 μg/m 3 in autumn semester.@*Conclusion@#PM 2.5 levels in the classrooms varied according to time, the horizontal space, and the vertical space, and the level of indoor PM 2.5 pollution largely depended on outdoor pollution sources. Differences in PM 2.5 exposure were observed between.
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Polyvinylpyrrolidone is a macromolecular polymer with widespread use in industry as well as in medicine for various purposes. Its effect on cells cultured in vitro, however, has not been fully investigated. To elucidate this issue, we studied the influence of PVP K-30 on cultured HeLa cells. PVP K-30 treatment produced a dose- and time-dependent toxicity to HeLa cells. Cells exposed to PVP K-30 exhibited several morphological features of apoptosis. Gel electrophoresis of DNA from PVP K-30-treated cells showed typical apoptotic ladder. And flow cytometric analysis demonstrated that PVP K-30 induced cell cycle arrest at G2/M phase and the subsequent appearance of sub-G1 population. In addition, it was shown that procaspase-3 was activated in response to PVP K-30 treatment. We also found that alpha-tocopherol efficiently protected HeLa cells from PVP K-30 cytotoxicity. This is the first demonstration that PVP K-30 could induce apoptosis in HeLa cells and cell cycle arrest at G2/M phase, and that PVP K-30 toxicity could be attenuated by alpha-tocopherol.