Vision therapy system 4D combined with stereoscopic 3D training technology for the treatment of amblyopia / 国际眼科杂志(Guoji Yanke Zazhi)

AIM:To investigate the effect of vision therapy system 4D combined with stereoscopic 3D technology training for the treatment of amblyopia.METHODS: Prospective study. A total of 102 children with amblyopia who attended the clinic from January 2018 to January 2022 were selected, and they were randomly assigned into two groups by computer, with 51 cases in each group. Control group received stereoscopic 3D technology training, while observation group participated in vision therapy system 4D on the basis of control group. Then the overall effective rate, binocular visual function, spherical equivalent(SE), axial length(AL), mean corneal curvature(Km), best corrected visual acuity(BCVA)and visual evoked potential were compared between two groups.RESULTS: The overall efficacy rate was 94.1% in observation group, which was obviously higher than control group(74.5%; P<0.05). The improvement in binocular vision parameters simultaneous perception, total fusion, and stereoacuity were all more remarkable in observation group than in control group(P<0.05). The △SE, △AL and △Km yielded no statistical difference between two groups(P>0.05). The latency of two spatial frequencies(1°grid and 15'grid)showed a decline in both groups, and the decline was more notable in observation group than in control group(P<0.05). In both groups, BCVA improved, and the improvement was more significant in observation group compared with control group(P<0.05).CONCLUSION: Application of vision therapy system 4D combined with stereoscopic 3D technology training for amblyopia can effectively ameliorate the visual acuity, promote the reconstruction of simultaneous perception, total fusion, and stereoacuity without additional risk of myopic shift, and improve visual pathway function in children.

Shexiang Tongxin Dropping Pill () Protects against NaSO-Induced Hypoxia-Reoxygenation Injury in H9c2 Cells / 中国结合医学杂志

OBJECTIVES@#To investigate the protective effects of Shexiang Tongxin Dropping Pill (, STP) on NaSO-induced hypoxia-reoxygenation injury in cardiomyoblast H9c2 cells.@*METHODS@#The cell viability and levels of mRNA and protein expression in H9c2 cells were determined following NaSO-induced hypoxia using Hoechst staining, annexin V/propidium iodide (PI) flow cytometry, real-time polymerase chain reaction and Western blot analysis.@*RESULTS@#STP pretreatment significantly increased the viability and inhibited aberrant morphological changes in H9c2 cardiomyoblast cells induced by NaSO treatment (P<0.05). In addition, STP pretreatment attenuated NaSO-induced hypoxic damage, down-regulated the expression of pro-apoptotic Bax, and up-regulated the expression of anti-apoptotic Bcl-2 in H9c2 cells (P<0.05).@*CONCLUSIONS@#STP was strongly cardioprotective in hypoxia-reoxygenation injury by preventing hypoxic damage and inhibiting cellular apoptosis. These results further support the use of STP as an effective drug for the treatment of ischemic heart disease.

Effect of jianpi tongluo jiedu recipe on expression levels of COX-2, NF-kappaBp65, and Bcl-2 in gastric mucosa of patients with precancerous lesions of gastric cancer / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To explore the effect of Jianpi Tongluo Jiedu Recipe (JTJR) on protein expression levels of COX-2, NF-kappaBp65, Bcl-2, and Bax, mRNA expression levels of COX-2 and Bcl-2, and the apoptotic index (Al) in gastric mucosa of patients with precancerous lesions of gastric cancer (PL-GC).</p><p><b>METHODS</b>Totally 65 PLGC patients were recruited and treated by JTJR (modified by syndrome typing), one dose per day for six successive months. Protein expression levels of COX-2, NF-KBp65, Bcl-2, and Bax were detected in 65 patients using immunohistochemical (IHC) assay before and after treatment. mRNA expression levels of COX-2 and Bcl-2 were detected in 54 patients using reverse transcription-polymerase chain reaction (RT-PCR). Meanwhile, changes of Al was detected in 65 patients using TdT-mediated dUTP-biotin nick end labeling (TUNEL) fluorescence method.</p><p><b>RESULTS</b>After treatment with JTJR, positive protein expression levels of COX-2, NF-KBp65, and Bcl-2 were obviously decreased in the gastric mucosa of PLGC patients (P <0.01), but Bax positive protein expression was found to be higher (P < 0.05). At the same time mRNA expression levels of COX-2 and Bcl-2 were significantly lower after treatment than before treatment (P < 0.05, P < 0.01); Al also increased after treatment (P < 0.05).</p><p><b>CONCLUSION</b>JTJR could promote apoptosis possibly via NF-kappaBp65/COX-2, COX-2/Bcl-2, and NF-kappaBp65/Bcl-2 signaling pathways, thereby affecting PLGC patients.</p>

Anti-atherosclerotic Effects of Bear Bile Powder in Shexiang Tongxin Dripping Pill: a Mechanism Study / 中国中西医结合杂志

<p><b>UNLABELLED</b>OBJECTIVE : To study the anti-atherosclerotic mechanism of bear bile powder (BBP) in Shexiang Tongxin Dripping Pill (STDP) , and to provide scientific evidence for treating atherosclerosis (AS) by its therapeutic characteristics of cool resuscitation.</p><p><b>METHODS</b>AS model was duplicated using ApoE-/- gene knocked mice fed with high-fat diet. Thirty ApoE-/- deficient male mice were divided into four groups according to body weight using random digit table, i.e., the model group (A, n =9), the STDP group (B, n=E7), the STDP without BBP group (C, n =7), and the BBP group (D, n =9). Besides, another 9 C57BL/6J male mice of the same age were recruited as a normal control group (E). All mice in Group B, C, and D were respectively administered with corresponding drugs (30, 30, and 0. 33 mg/kg) by gastrogavage. Equal volume of normal saline was administered to mice in Group A and E. All medication lasted for 8 successive weeks. Serum levels of inflammatory cytokines such as interleukin 2 (IL-2), interleukin 6 (IL-6), tumor necrosis factor a (TNF-α), interferon y (IFNγ), and oxidized low-density lipoprotein (ox-LDL) were measured by ELISA. Serum levels of malondialdehyde (MDA), activities of glutathione (GSH) and superoxide dismutase (SOD) were determined using biochemical assay. Contents of reactive oxygen species (ROS) in the aortic root was detected by dihydroethidum (DHE) fluorescent probe. Expression levels of microRNAs (such as miR-20, miR-21, miR-126, and miR-155) were detected by real-time PCR.</p><p><b>RESULTS</b>The fluorescence intensity of the aorta was obviously enhanced in Group A. But it was obviously attenuated in Group B, C, and D, and the attenuation was the most in Group B. Compared with Group E, serum levels of IL-2, IL-6, TNF-α, IFN-γ, oxLDL, and MDA all increased (P <0. 01), GSH contents and SOD activities decreased (P <0. 01), expression levels of miR-126, miR-21, and miR-155 in aorta increased (P <0. 01), and the expression level of miR-20 decreased in Group A (P<0. 01). Compared with Group A, serum levels of IL-2, IL-6, TNF-α, IFN-γ, oxLDL, and MDA were all down-regulated (P <0. 01), GSH contents and SOD activities were up-regulated (P <0. 01), expression levels of miR-126, miR-21, and miR-155 in aorta were down-regulated in Group B, C, and D (P <0. 01). The expression level of miR20 was up-regulated in Group B and D (P <0. 01). Compared with Group B, serum levels of IL-2, IL-6, TNF-α, IFN-γ increased (P <0.01); GSH contents and SOD activities decreased, levels of MDA and oxLDL increased (P <0. 01) in Group C and D. Expression levels of miR-20 and miR-155 were down-regulated in Group C and D (P <0. 01).</p><p><b>CONCLUSIONS</b>STDP played roles in significantly regulating inflammatory factors and oxidative stress factors. Its mechanism might be possibly associated with regulating expressions of miR-126, miR-21, miR-155, and miR-20 in aorta. BBP played significant roles in STDP.</p>

Effect of electric acupoint stimulation on shivering in cesarean section / 中国针灸

<p><b>OBJECTIVE</b>To explore the efficacy of electric acupoint stimulation on shivering in cesarean section.</p><p><b>METHODS</b>Eighty cases of parturients, under the America Society of Anesthesiologists (ASA) physical status II , were randomized into a transcutaneous electrical acupoint stimulation (TEAS) assisted anesthesia group (group A) and an anesthesia group (group B). Spinal-epidural anesthesia(CSEA) puncture was applied to both groups and 8 mg of 0. 75% bubivacaine was given by spinal injection, the block level was T4 T8. In group A, TEAS was applied before CSEA at paired acupoints-ipsilateral Hegu (LI 4)-Laogong (PC 8) and Sanyinjiao (SP 6)-Zusanli (ST 36) till ending the surgery. The 4 pair of bilateral acupoints were fixed with self-adhesive electrodes and connected with Han's acupoint and nerve stimulator (HANS, LH402H), the frequency was 2 Hz/ 15 Hz, the intensity was 10- 30 mA and the form was densedisperse wave within the patients' tolarance. The heart rate (HR), mean arterial pressure (MAP), oxyhemoglobin saturation (SPO) and shivering degree were recorded before anesthesia (To), 1 min after anesthesia puncture (Ti), 1 min after the delivery (Tz), during abdomen closure (T3) and at the end of surgery (T4).</p><p><b>RESULTS</b>The occurrence rate of shivering was 35. 0% (14/40) in group A, which was lower to 67. 5% (27/40, P<0. 05) in group B; the degree of shivering was lighter in group A than that in group B at T2, T3 and T4 (all P<0. 01). In group A, HR was faster at T1 and T2 compared to that at To (all P<0. 05), while at T3 and T4, the HR was the same with that before anesthesia (all P>0. 05). In group B, the HR was faster at T1, T2, T3 and T4 compared to that at T0 (P<0. 05, P<0. 01). In both groups, the MAP was lower at T1, T2 (P<0.05,P<0.01) and resumed to that before anesthesia at T3 and T4 (all P>0.05); there was no statistical significance of SPO2 in both groups (all P>0.05).</p><p><b>CONCLUSION</b>TEAS can reduce the occurrence rate of shivering and steady the heart rate in cesarean section.</p>

Concurrent versus sequential systemic chemotherapy and whole brain radiation therapy for brain matastases in non-small-cell lung cancer patients / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To evaluate the efficacy, survival and toxicity in patients with brain metastases from non-small cell lung cancer (NSCLC), treated with concurrent systemic chemotherapy and whole brain radiation therapy (WBRT) or sequential systemic chemotherapy/WBRT.</p><p><b>METHODS</b>A total of 60 NSCLC patients with brain metastases were divided into two groups in this prospective clinical study: concurrent systemic chemotherapy and WBRT group (concurrent group) and sequential systemic chemotherapy/WBRT group (sequential group).</p><p><b>RESULTS</b>Of 59 assessable patients, the overall response rate was 22.0%, and the brain response rate was 35.6%; the median progression-free survival time was 3.0 months, and the overall 1- and 2-year survival rates were 55% and 24.4%, respectively, with a median survival time of 16.0 months. The overall response rate was 20.0% in the concurrent group and 24.1% in sequential group (P > 0.05). The brain response rates of 43.3% in concurrent group and 27.6% in sequential group were also not significantly different (P > 0.05). The median progression-free survival time for the patients in the concurrent group was 3.0 months versus 4.0 months in the sequential group, and the median survival time was 16.0 months versus 13.0 months (all P > 0.05). The 1- and 2-year survival rates were 58.5% and 37.2% versus 52.9% and 18.9%, respectively, with a significant difference in the 2-year survival rate between the two groups (P = 0.011). In the sequential group, leukopenia was more frequent during chemotherapy than that in the concurrent group (P = 0.029).</p><p><b>CONCLUSION</b>Concurrent systemic chemotherapy and WBRT is effective with tolerable adverse events in treating brain metastasis from NSCLC with an encouraging survival, and deserves further large sample and randomized multicenter clinical trials.</p>

Cytoplasmic dynein participates in meiotic checkpoint inactivation in mouse oocytes by transporting cytoplasmic mitotic arrest-deficient (Mad) proteins from kinetochores to spindle poles.

The present study was designed to investigate the localization and function of cytoplasmic dynein (dynein) during mouse oocyte meiosis and its relationship with two major spindle checkpoint proteins, mitotic arrest-deficient (Mad) 1 and Mad2. Oocytes at various stages during the first meiosis were fixed and immunostained for dynein, Mad1, Mad2, kinetochores, microtubules, and chromosomes. Some oocytes were treated with nocodazole before examination. Anti-dynein antibody was injected into the oocytes at germinal vesicle (GV) stage before the examination of its effects on meiotic progression or Mad1 and Mad2 localization. Results showed that dynein was present in the oocytes at various stages from GV to metaphase II and the locations of Mad1 and Mad2 were associated with dynein's movement. Both Mad1 and Mad2 had two existing states: one existed in the cytoplasm (cytoplasmic Mad1 or cytoplasmic Mad2), which did not bind to kinetochores, while the other bound to kinetochores (kinetochore Mad1 or kinetochore Mad2). The equilibrium between the two states varied during meiosis and/or in response to the changes of the connection between microtubules and kinetochores. Cytoplasmic Mad1 and Mad2 recruited to chromosomes when the connection between microtubules and chromosomes was destroyed. Inhibition of dynein interferes with cytoplasmic Mad1 and Mad2 transportation from chromosomes to spindle poles, thus inhibits checkpoint silence and delays anaphase onset. These results indicate that dynein may play a role in spindle checkpoint inactivation.

Regulation of intracellular MEK1/2 translocation in mouse oocytes: cytoplasmic dynein/dynactin-mediated poleward transport and cyclin B degradation-dependent release from spindle poles.

We recently reported that MEK1/2 plays an important role in microtubule organization and spindle pole tethering in mouse oocytes, but how the intracellular transport of this protein is regulated remains unknown. In the present study, we investigated the mechanisms of poleward MEK1/2 transport during the prometaphase I/metaphase I transition and MEK1/2 release from the spindle poles during the metaphase I/anaphase I transition in mouse oocytes. Firstly, we found that p-MEK1/2 was colocalized with dynactin at the spindle poles. Inhibition of the cytoplasmic dynein/dynactin complex by antibody microinjection blocked polar accumulation of p-MEK1/2 and caused obvious spindle abnormalities. Moreover, coimmunoprecipitation of p-MEK1/2 and dynein or dynactin from mouse oocyte extracts confirmed their association at metaphase I. Secondly, disruption of microtubules by nocodazole resulted in the failure of poleward p-MEK1/2 transport. Whereas, when the nocodazole-treated oocytes were recovered in fresh culture medium, the spindle reformed and p-MEK1/2 relocalized to the spindle poles. Finally, we examined the mechanism of p-MEK1/2 release from the spindle poles. In control oocytes, polar p-MEK1/2 was gradually released during metaphase I/anaphase I transition. By contrast, in the presence of nondegradable cyclin B (Delta90), p-MEK1/2 still remained at the spindle poles at anaphase I. Our results indicate that poleward MEK1/2 transport is a cytoplasmic dynein/dynactin-mediated and spindle microtubule-dependent intracellular movement, and that its subsequent anaphase release from spindle poles is dependent on cyclin B degradation.

MEK1/2 regulates microtubule organization, spindle pole tethering and asymmetric division during mouse oocyte meiotic maturation.

It is well known that MAPK plays pivotal roles in oocyte maturation, but the function of MEK (MAPK kinase) remains unknown. We have studied the expression, subcellular localization and functional roles of MEK during meiotic maturation of mouse oocytes. Firstly, we found that MEK1/2 phoshorylation (p-MEK1/2, indicative of MEK activation) was low in GV (germinal vesicle) stage, increased 2h after GVBD (germinal vesicle breakdown), and reached the maximum at metaphase II. Secondly, we found that P-MEK1/2 was restricted in the GV prior to GVBD. In prometaphase I and metaphase I, P-MEK1/2 was mainly associated with the spindle, especially with the spindle poles. At anaphase I and telophase I, p-MEK1/2 became diffusely distributed in the region between the separating chromosomes, and then became associated with the midbody. The association of p-MEK1/2 with spindle poles was further confirmed by its colocalization with the centrosomal proteins, gamma-tubulin and NuMA. Thirdly, we have investigated the possible functional role of MEK1/2 activation by intravenous administration and intrabursal injection of a specific MEK inhibitor, U0126, and by microinjection of MEK siRNA into oocytes. All these manipulations cause disorganized spindle poles and spindle structure, misaligned chromosomes and larger than normal polar bodies. Our results suggest that MEK1/2 may function as a centrosomal protein and may have roles in microtubule organization, spindle pole tethering and asymmetric division during mouse oocyte maturation.

Removal of Low Concentration Formaldehyde in Indoor Air by Chemisorption Using Copper Sulfate / 环境与健康杂志

Objective To research the removal of the low concentration of formaldehyde in the indoor air by using copper sulfate.Methods The low concentration of formaldehyde(10.0 mg/L)in the indoor air was determined by the way of MBTH spectrophotometry.The influence of pH,chelon and concentration on the removal of different concentration formaldehyde was investigated by the way of chemisorption.Results When pH was 11.99,12.86,13.08 and 13.42,using copper sulfate,the removal rate of 10.0 mg/L formaldehyde was 43.82%,62.75%,69.21% and 73.40% respectively.When the concentration of copper sulfate was at 3.0 g/L,5.0 g/L,7.0 g/L and 10.0 g/L,the removal rate was 51.43%,73.40%,66.36% and 62.18% respectively in the condition of pH=13.42.When used potassium sodium tartrate and EDTA as the ehelon,pH=13.42,concentration of copper sulfate was 5.0 g/L,the removal rate of 2.0 mg/L formaldehyde was 77.21% and 62.51% respectively,that of 10.0 mg/L formaldehyde was 86.54% and 73.40% respectively,that of 100.0mg/L formaldehyde was 96.71% and 91.32% respectively.Conclusion Using potassium sodium tartrate as the chelon,at pH=13.42,5.0 g/L copper sulfate can produce a good removal efficiency for indoor low level formaldehyde.

Degradation of securin in mouse and pig oocytes is dependent on ubiquitin-proteasome pathway and is required for proteolysis of the cohesion subunit, Rec8, at the metaphase-to-anaphase transition.

Although securin/separase/cohesion pathway was reported to regulate chromosome segregation during meiotic metaphase-to-anaphase transition, little biochemical evidence was provided. We recently found that oocytes could not progress beyond meiotic metaphase when ubiquitin-proteasome pathway was inhibited, but the mechanisms remain unclear. In the present study, we investigated the quantity of securin and Rec8 protein and the localization of securin, a cohesion subunit, during oocyte meiosis providing data in support of the hypothesis that the effect of ubiquitin-proteasome pathway on metaphase-to-anaphase transition was mediated by regulating securin and Rec8 degradation in mouse and pig oocytes. In germinal vesicle-stage oocytes, immunostaining of securin was mainly localized in the germinal vesicle. Shortly after germinal vesicle breakdown, immunoreactive securin accumulated around the condensed chromosomes at prometaphase I. At metaphase I and metaphase II, when chromosomes were organized at the equatorial plate, immunoreactive securin was concentrated around the aligned chromosomes, putatively associated with the position of the metaphase spindle. The accumulation of securin could not be detected at anaphase I and anaphase II. In both mouse and pig oocytes, Western blot analysis showed that securin protein was low at germinal vesicle stage, reached the highest level at metaphase I, while decreased at anaphase I. Securin was increased again at metaphase II, while it was decreased at anaphase II. Rec8 protein was present in germinal vesicle-stage oocytes and remained until metaphase I, while it was decreased at anaphase I. Like securin, Rec8 was increased at metaphase II, while it was decreased again at anaphase II. The inhibition of the ubiquitin-proteasome pathway inhibited the decrease in securin and Rec8 at metaphase-to-anaphase transitions in both mouse and pig oocytes. Microinjection of securin antibody into MII-arrested oocytes leads to the degradation of Rec8. In conclusion, these results suggest that the proteolysis of securin is dependent on ubiquitin-proteasome pathway and is necessary for the degradation of Rec8 during meiotic metaphase-to-anaphase transitions in mouse and pig oocytes.

Cell-cycle-dependent subcellular localization of cyclin B1, phosphorylated cyclin B1 and p34cdc2 during oocyte meiotic maturation and fertilization in mouse.

M phase or maturation promoting factor (MPF), a kinase complex composed of the regulatory cyclin B and the catalytic p34cdc2 kinase, plays important roles in meiosis and mitosis. This study was designed to detect and compare the subcellular localization of cyclin B1, phosphorylated cyclin B1 and p34cdc2 during oocyte meiotic maturation and fertilization in mouse. We found that all these proteins were concentrated in the germinal vesicle of oocytes. Shortly after germinal vesicle breakdown, all these proteins were accumulated around the condensed chromosomes. With spindle formation at metaphase I, cyclin B1 and phosphorylated cyclin B1 were localized around the condensed chromosomes and concentrated at the spindle poles, while p34cdc2 was localized in the spindle region. At the anaphase/telophase transition, phosphorylated cyclin B1 was accumulated in the midbody between the separating chromosomes/chromatids, while p34cdc2 was accumulated in the entire spindle except for the midbody region. At metaphase II, both cyclin B1 and p34cdc2 were horizontally localized in the region with the aligned chromosomes and the two poles of the spindle, while phosphorylated cyclin B1 was localized in the two poles of spindle and the chromosomes. We could not detect a particular distribution of cyclin B1 in fertilized eggs when the pronuclei were initially formed, but in late pronuclei cyclin B1 was accumulated in the pronuclei. p34cdc2 and phosphorylated cyclin B1 were always concentrated in one pronucleus after parthenogenetic activation or in two pronuclei after fertilization. At metaphase of 1-cell embryos, cyclin B1 was accumulated around the condensed chromosomes. Cyclin B1 was accumulated in the nucleus of late 2-cell embryos but not in early 2-cell embryos. Furthermore, we also detected the accumulation of p34cdc2 in the nucleus of 2- and 4-cell embryos. All these results show that cyclin B1, phosphorylated cyclin B1 and p34cdc2 have similar distributions at some stages but different localizations at other stages during oocyte meiotic maturation and fertilization, suggesting that they may play a common role in some events but different roles in other events during oocyte maturation and fertilization.

Inducible nitric oxide synthase-derived nitric oxide regulates germinal vesicle breakdown and first polar body emission in the mouse oocyte.

The present study investigated the subcellular localization of inducible nitric oxide synthase (iNOS) during mouse oocyte meiotic maturation and fertilization using confocal microscopy, and further studied the roles of iNOS-derived NO in oocyte maturation by using an iNOS-specific inhibitor aminoguanidine (AG) and iNOS antibody microinjection. In germinal vesicle-stage oocytes, iNOS immunoreactivity was mainly localized in the germinal vesicle. Shortly after germinal vesicle breakdown, the iNOS immunoreactivity accumulated around the condensed chromosomes. At metaphase I and metaphase II, with the organization of chromosomes to the equatorial plate, iNOS immunoreactivity was concentrated around the aligned chromosomes, putatively the position of the metaphase spindle. The accumulation of iNOS immunoreactivity could not be detected at anaphase I and anaphase II. However, at telophase I and telophase II, the staining of iNOS was concentrated in the region between the separating chromosomes/chromatids. Furthermore, the staining of iNOS also accumulated in the male and female pronuclei in fertilized eggs. Germinal vesicle breakdown and the first polar body emission of the oocytes were significantly blocked by the iNOS-specific inhibitor AG in a dose-dependent manner. The germinal vesicle breakdown in oocytes injected with iNOS antibody was also inhibited. We found that the phosphorylation of mitogen-activated protein kinase in oocytes after germinal vesicle breakdown was inhibited by AG treatment. The control oocytes extruded a normal first polar body, while the AG-treated oocytes exhibited an elongated protrusion or no elongated protrusion. The results of confocal microscopy showed that the AG-treated oocytes were arrested at anaphase I-telophase I. Our results suggest that the iNOS-derived NO pathway plays important roles in mouse oocyte meiotic maturation, especially in germinal vesicle breakdown and the anaphase-telophase transition.

Regulation of ubiquitin-proteasome pathway on pig oocyte meiotic maturation and fertilization.

Degradation of proteins mediated by the ubiquitin-proteasome pathway (UPP) plays essential roles in the eukaryotic cell cycle. The main aim of the present study was to analyze the functional roles and regulatory mechanisms of the UPP in pig oocyte meiotic maturation, activation, and early embryo mitosis by drug treatment, Western blot analysis, and confocal microscopy. By using the hypoxanthine-maintained meiotic arrest model, we showed that the meiotic resumption of both cumulus-enclosed oocytes and denuded oocytes was stimulated in a dose- and time-dependent manner by two potent and cell-permeable proteasome inhibitors. Both the mitogen-activated protein kinase (MAPK) kinase inhibitor U0126 and the maturation-promoting factor inhibitor roscovitine overcame the stimulation of germinal vesicle breakdown induced by proteasome inhibitors. The phosphorylation of MAPK and p90rsk and the expression of cyclin B1 increased in a dose- and time-dependent manner when treated with proteasome inhibitors during oocyte in vitro-maturation culture. Both U0126 and roscovitine inhibited the phosphorylation of MAPK and p90rsk, and the synthesis of cyclin B1 stimulated by proteasome inhibitors. When matured oocytes were pretreated with proteasome inhibitors and then fertilized or artificially activated, the second polar body emission and the pronuclear formation were inhibited, and the dephosphorylation of MAPK and p90rsk as well as the degradation of cyclin B1 that should occur after oocyte activation were also inhibited. We also investigated, to our knowledge for the first time, the subcellular localization of 20S proteasome alpha subunits at different stages of oocyte and early embryo development. The 20S proteasome alpha subunits were accumulated in the germinal vesicle, around the condensed chromosomes at prometaphase, with spindle at metaphase I and II, the region between the separating chromosomes, and especially the midbody at anaphase I and telophase I, the pronucleus, and the nucleus in early embryonic cells. In conclusion, our results suggest that the UPP is important at multiple steps of pig oocyte meiosis, fertilization, and early embryonic mitosis and that it may play its roles by regulating cyclin B1 degradation and MAPK/p90rsk phosphorylation.