ROS-induced oxidative stress and mitochondrial dysfunction: a possible mechanism responsible for noise-induced ribbon synaptic damage.

Evidence suggests that damage to the ribbon synapses (RS) may be the main cause of auditory dysfunction in noise-induced hearing loss (NIHL). Oxidative stress is implicated in the pathophysiology of synaptic damage. However, the relationship between oxidative stress and RS damage in NIHL remains unclear. To investigate the hypothesis that noise-induced oxidative stress is a key factor in synaptic damage within the inner ear, we conducted a study using mice subjected to single or repeated noise exposure (NE). We assessed auditory function using auditory brainstem response (ABR) test and examined cochlear morphology by immunofluorescence staining. The results showed that mice that experienced a single NE exhibited a threshold shift and recovered within two weeks. The ABR wave I latencies were prolonged, and the amplitudes decreased, suggesting RS dysfunction. These changes were also demonstrated by the loss of RS as evidenced by immunofluorescence staining. However, we observed threshold shifts that did not return to baseline levels following secondary NE. Additionally, ABR wave I latencies and amplitudes exhibited notable changes. Immunofluorescence staining indicated not only severe damage to RS but also loss of outer hair cells. We also noted decreased T-AOC, ATP, and mitochondrial membrane potential levels, alongside increased hydrogen peroxide concentrations post-NE. Furthermore, the expression levels of 4-HNE and 8-OHdG in the cochlea were notably elevated. Collectively, our findings suggest that the production of reactive oxygen species leads to oxidative damage in the cochlea. This mitochondrial dysfunction consequently contributes to the loss of RS, precipitating an early onset of NIHL.

Yacon as an alternative host plant for Encarsia formosa mass-rearing: validating a multinomial theorem for bootstrap technique in life table research.

BACKGROUND: Yacon (Smallanthus sonchifolius) is a broadleaf host plant suitable for rearing the greenhouse whitefly, Trialeurodes vaporariorum (Westwood). Here, the possibility of using yacon as an alternative host plant for production of the parasitoid, Encarsia formosa Gahan, one of the most important natural enemies of whiteflies, was explored. Data on the demographic characteristics, parasitism rate, and host-feeding rate were collected and analyzed using the TWOSEX-MSChart, CONSUME-MSChart, and TIMING-MSChart computer programs, and then contrasted with comparable data from the more commonly utilized host plant, tobacco. RESULTS: Higher fecundity (F) (190.13 eggs/female) and more oviposition days (Od ) (16.60 days) were observed in E. formosa when yacon was used as the host plant for rearing T. vaporariorum, compared with when tobacco was used (F = 150.13 eggs/female, Od = 15.27 days). The intrinsic rate of increase (r), finite rate of increase (λ), and net reproduction rate (R0 ) were significantly higher in E. formosa parasitizing T. vaporariorum reared on yacon compared with those parasitizing tobacco-reared T. vaporariorum. Furthermore, the net host-feeding rate (C0 = 40.87 prey/parasitoid), net killing rate (Z0 = 239.73 prey/parasitoid), and finite killing rate ( υ = 0.2560/day) for E. formosa on yacon-reared whiteflies were significantly higher than those from tobacco-reared whiteflies. CONCLUSION: Our results showed that yacon is more suitable than tobacco as a host plant for mass-rearing E. formosa for biological control programs to manage whiteflies. An innovative application of the multinomial theorem for calculating the exact probability of bootstrap samples in life table research was also introduced. © 2021 Society of Chemical Industry.

[F4.8 visual miniature nephroscope for the diagnosis and treatment of hematospermia].

OBJECTIVE: To explore the practicability and safety of the F4.8 visual miniature nephroscope in the diagnosis and treatment of hematospermia. METHODS: This study included 12 cases of refractory hematospermia accompanied by perineal or lower abdominal pain and discomfort. All the patients failed to respond to two months of systemic anti-inflammatory medication and local physiotherapy. Seminal vesicle tumor and tuberculosis were excluded preoperatively by rectal seminal vesicle ultrasonography, MRI or CT. Under epidural anesthesia, microscopic examination was performed with the F4.8 miniature nephroscope through the urethra and ejaculatory duct orifice into the seminal vesicle cavity, the blood clots washed out with normal saline, the seminal vesicle stones extracted by holmium laser lithotripsy and with the reticular basket, the seminal vesicle polyps removed by holmium laser ablation and vaporization, and the seminal vesicle cavity rinsed with diluted iodophor after operation. RESULTS: Of the 10 patients subjected to bilateral seminal vesiculoscopy, 3 with unilateral and 2 with bilateral seminal vesicle stones were treated by holmium laser lithotripsy, saline flushing and reticular-basket removal, 2 with seminal vesicle polyps by holmium laser ablation and vaporization, and the other 3 with blood clots in the seminal vesicle cavity by saline flushing for complete clearance. The 2 patients subjected to unilateral seminal vesiculoscopy both received flushing of the seminal vesicle cavity for clearance of the blood clots. The operations lasted 10－55 (25 ± 6) minutes. There were no such intra- or post-operative complications as rectal injury, peripheral organ injury, and external urethral sphincter injury. The urethral catheter was removed at 24 hours, anti-infection medication withdrawn at 72 hours, and regular sex achieved at 2 weeks postoperatively. The patients were followed up for 6－20 (7 ± 2.3) months, during which hematospermia and related symptoms disappeared in 10 cases at 3 months and recurrence was observed in the other 2 at 4 months after surgery but improved after antibiotic medication. CONCLUSIONS: The F4.8 visual miniature nephroscope can be applied to the examination of the seminal vesicle cavity and treatment of seminal vesicle stones and polyps, with the advantages of minimal invasiveness, safety and reliability.

Clinical effects of Huoxue Zhuyu Qingdu Decoction combined with routine treatment on patients with sepsis-induced acute kidney injury / 中成药

AIM To investigate clinical effects of Huoxue Zhuyu Qingdu Decoction combined with routine treatment on patients with sepsis-induced acute kidney injury.METHODS One hundred and twenty-two patients were randomly and equally divided into control group for a four-week routine treatment,and observation group for a four-week intervention of Huoxue Zhuyu Qingdu Decoction on the basis of routine treatment.RESULTS Significantly decreased post-treatment APACHE Ⅱ,SOFA scores,and TNF-α,IL-6,IL-18,Scr,CysC,NGAL levels in both groups (P ＜ 0.05),and markedly lower values of the indices in the observation group than in the control group were observed (P ＜ 0.05).Meanwhile,the observation group demonstrated its superiority in terms of significantly shorter hospitalization time and lower mortality rate (P ＜ 0.05).CONCLUSION For patients with sepsisinduced acute kidney injury,a combination therapy of Huoxue Zhuyu Qingdu Decoction and routine treatment contributes to a good prognosis due to their synergistic effect in alleviating inflammatory reactions and improving renal injury.

Combined standard percutaneous nephrolithotomy and 4.8Fr micro- percutaneous nephrolithotomy and for multiple renal calculi (46 cases) / 中国内镜杂志

Objective To explore the application of visible standard channel combined with F4.8 visible puncture percutaneous nephrolithotomy in the treatment of multiple renal calculi. Methods The clinical data of 46 patients with multiple renal calculi from October 2015 to September 2016 were retrospectively analyzed. There were 28 male and 18 female, with a mean age of 42.6 years (aged from 25 to 65 years). Stone diameter 3.0~5.2 cm, average (4.3 ± 0.8) cm. Application of F4.8 visual puncture assisted angioplasty to establish the standard channel, nephrolithotomy combined with ultrasonic lithotripsy treatment in the field of visible stones, then apply the F4.8 visual micro puncture percutaneous nephrolithotomy combined with holmium laser treatment of other parts of the stone, summarizes the channel establishment total time, operation time, blood red protein decreased and stone clearance rate and complication index. Results All cases were successfully established single standard channel under the guidance of F4.8 visual puncture, 24 cases were combined with single ultramicro channel, 16 cases were combined with double ultramicro channels, and the other 6 cases were combined with the three ultra micro channels. Postoperative indwelling single renal fistula, micro channel indwelling fistula, postoperative indwelling F5 double J tube. F4.8 visual puncture established standard channel establishment time (6.8 ± 1.8) min, single F4.8 visible puncture ultra - channel establishment time of (4.5 ± 0.9) min, operation time of (92.0 ± 15.0) min. A stone clearance rate was 91.3% (42/46), a decrease in hemoglobin value of (12.2 ± 2.5) g/L, 8 cases of postoperative fever, given anti-inflammatory treatment improved, 4 cases with residual calyceal stones visible 0.5~0.8 cm, given extracorporeal shock wave lithotripsy combined with postural drainage, stone, 1 months after the treatment of stones were discharged, did not appear Shi Jie, delayed bleeding, adjacent organ injury, ureteral injury cases. Conclusion Visual standard channel combined with F4.8 ultra visible puncture percutaneous nephrolithotomy in treatment of multiple renal calculi has the advantages of reducing the large number of channels, high stone clearance rate, safety, less complications, F4.8 was used to establish the visual puncture channel is more safe and accurate.

Combined standard percutaneous nephrolithotomy and 4.8Fr micro- percutaneous nephrolithotomy and for multiple renal calculi (46 cases) / 中国内镜杂志

Objective To explore the application of visible standard channel combined with F4.8 visible puncture percutaneous nephrolithotomy in the treatment of multiple renal calculi. Methods The clinical data of 46 patients with multiple renal calculi from October 2015 to September 2016 were retrospectively analyzed. There were 28 male and 18 female, with a mean age of 42.6 years (aged from 25 to 65 years). Stone diameter 3.0~5.2 cm, average (4.3 ± 0.8) cm. Application of F4.8 visual puncture assisted angioplasty to establish the standard channel, nephrolithotomy combined with ultrasonic lithotripsy treatment in the field of visible stones, then apply the F4.8 visual micro puncture percutaneous nephrolithotomy combined with holmium laser treatment of other parts of the stone, summarizes the channel establishment total time, operation time, blood red protein decreased and stone clearance rate and complication index. Results All cases were successfully established single standard channel under the guidance of F4.8 visual puncture, 24 cases were combined with single ultramicro channel, 16 cases were combined with double ultramicro channels, and the other 6 cases were combined with the three ultra micro channels. Postoperative indwelling single renal fistula, micro channel indwelling fistula, postoperative indwelling F5 double J tube. F4.8 visual puncture established standard channel establishment time (6.8 ± 1.8) min, single F4.8 visible puncture ultra - channel establishment time of (4.5 ± 0.9) min, operation time of (92.0 ± 15.0) min. A stone clearance rate was 91.3% (42/46), a decrease in hemoglobin value of (12.2 ± 2.5) g/L, 8 cases of postoperative fever, given anti-inflammatory treatment improved, 4 cases with residual calyceal stones visible 0.5~0.8 cm, given extracorporeal shock wave lithotripsy combined with postural drainage, stone, 1 months after the treatment of stones were discharged, did not appear Shi Jie, delayed bleeding, adjacent organ injury, ureteral injury cases. Conclusion Visual standard channel combined with F4.8 ultra visible puncture percutaneous nephrolithotomy in treatment of multiple renal calculi has the advantages of reducing the large number of channels, high stone clearance rate, safety, less complications, F4.8 was used to establish the visual puncture channel is more safe and accurate.

Radiation-induced expression of IER5 is dose-dependent and not associated with the clinical outcomes of radiotherapy in cervical cancer.

This study aimed to investigate the expression of the immediate-early response 5 (IER5) gene in cervical cancer tissues and explore the association between the expression of IER5 and the clinical outcomes of radiotherapy. We collected specimens by surgery or biopsy and obtained 53 specimens from tissues after radiotherapy and 16 specimens from tissues before radiotherapy. Immunohistochemistry and western blotting were used to assess the protein expression levels of IER5. Quantitative polymerase chain reaction (qPCR) was performed to assess the mRNA expression levels of IER5. The protein and mRNA expression levels of IER5 in cervical cancer patients treated with radiation doses ≥20 Gy were significantly higher than in those treated with radiation doses <20 Gy (P<0.05) and before treatment with radiotherapy. Moreover, the expression of IER5 was significantly positively correlated with the radiation dose (immunohistochemistry: r=0.548, P=0.019; qPCR: r=0.671, P=0.002; western blotting: r=0.573, P<0.0001). Radiotherapy induced the upregulated expression of IER5 and this was dependent on the radiation dose. However, the radiation-induced expression of IER5 was not associated with the clinical outcomes of radiotherapy in cervical cancer.

Characteristics and evaluation on heavy metal contamination in Changchun municipal waste landfill after closure.

In the present study, comprehensive investigation on the spot and typical investigation method were used to assess Mn, Zn, Pb, Cd, Cr, Ni, As and Cu level, pH value, organic matter, total nitrogen and total phosphorus contents in soil of Changchun municipal waste landfill. The results showed that soil in the closure area of Changchun municipal waste landfill was alkaline in nature and the average value of organic matter, total nitrogen and total phosphorus contents were lower than that in normal black soil in Changchun City of Jilin Province. Single factor indices of As, Pb and Cr content was > 1, where P(As) was 1.131, P(Pb) 1.061 and P(Cr) 1.092 mildly contaminated. In different sample spots but the same landfill time, the comprehensive Nemerow contamination indexes of 7a (5 #) and 7a (2 #) were P(2 comprehensive) = 1.176 and P(5 comprehensive) = 1.229. The performance value of of heavy metal contamination in soil was similar and there was a low ecological risk.

[Health risk assessment of coke oven PAHs emissions].

Polycyclic aromatic hydrocarbons (PAHs) produced by coke oven are with strong toxicity and carcinogenicity. Taken typical coke oven of iron and steel enterprises as the case study, the dispersion and migration of 13 kinds of PAHs emitted from coke oven were analyzed using AERMOD dispersion model, the carcinogenic and non-carcinogenic risks at the receptors within the modeling domain were evaluated using BREEZE Risk Analyst and the Human Health Risk Assessment Protocol for Hazardous Waste Combustion (HHRAP) was followed, the health risks caused by PAHs emission from coke oven were quantitatively evaluated. The results indicated that attention should be paid to the non-carcinogenic risk of naphthalene emission (the maximum value was 0.97). The carcinogenic risks of each single pollutant were all below 1.0E-06, while the maximum value of total carcinogenic risk was 2.65E-06, which may have some influence on the health of local residents.

[Expressions of immunogenic molecules in low-dose radiotherapy-treated human renal clear cell carcinoma 786-0 cells].

OBJECTIVE: To explore the effects of low-dose radiation on the expression of immunogenic membrane molecules calreticulin (CRT) and MHC-I/II on the surface of human renal clear cell carcinoma 786-0 cells. METHODS: The inhibitory activity of low-dose radiation on cell line 786-0 was examined by CCK-8 assay. And the post-radiation membrane expressions of CRT, MHC-I and MHC-II were measured by flow cytometry while CRT was visualized by immunofluorescence photography. RESULTS: The inhibition rates on the proliferative capacities of four 786-0 cell lines rose with the incremental radiation doses of 0, 6, 12 and 24 Gy. And the CRT expression levels of each experimental group was significantly higher than that of the control group (P < 0.001). Along with incremental doses of irradiation, the average calreticulin fluorescence intensities increased gradually initially and then there was a downward trend. The membrane expressions of MHC-I and MHC-II of each experimental group was significantly higher than those of the control group (P < 0.05). As the irradiation dose increased, the average MHC-I fluorescence intensities increased gradually in a dose-dependent manner. CONCLUSION: The low-dose radiotherapy may up-regulate CRT and MHC class I/II related with the immunogenicity of tumor cells to induce immune response against tumors.

Clinical study on the association of ocular dominance with accommodation in myopia adult / 中华实验眼科杂志

Background Dominant eye is one of the functional asymmetric organ,and the dfference between dominant eye and undominant eye is a researching hotspot.But the study about accommodation in adult myopia is less.Objective This study was to determine the association between ocular dominances and accommodative factors in the subjects with adult myopia.Methods This study used prospective descriptive research method.Thirty-five subjects aged from 18 to 35 years with the myopia ranged from-2.00 D to-10.00 D and anisometropia less than 1.5 D,BCVA≥ 1.0 were recruited consecutively in this study.Ocular dominance was determined using the hole-inthe-card test and thumb test.Refractive error was measured with objective and subjective optometry,and amplitude of accommodation was measured by push-up test.Fusion cross cylinder(FCC) was used to measure the accommodative lag,and flipper test was applied to determine the accommodative facility.Oral informed consent was obtained from each subject before any relevant examination.Results No significant differences were found in the amplitude of accommodation (D),accommodative facility (cpm) and accommodative lag (D) between the dominant eye and undominant eye (accommodative amplitude:9.69 D±2.30 D vs.9.60 D±2.37 D,P =0.294 ;accommodative facility: 11.08 D±4.20 D vs.10.63 D± 4.60 D,P=0.260;accommodative lag:P=0.141).In the patients with the right eyes as dominance eyes,the accommodative amplitude of both eyes were (9.48±2.29) cpm and (9.33 ± 2.49) cpm,and accommodative facility were (10.50 ± 4.70) cpm and (9.99 ± 4.90) cpm.There were no significant differences between the right and left eyes in the accommodative amplitude,accommodative facility and accommodative lag (P =0.319,0.116,0.590).In the patients with the left eyes as dominant eyes,the accommodative amplitude of both eyes were (9.91±2.35)D and (9.88±2.26) D,and accommodative facility were (10.70±3.77)cpm and (11.25 ±4.27) cpm.No significant differences were seen between the right eyes and left eyes in the accommodative amplitude,accommodative facility and accommodative lag (P =0.749,0.295,0.238).Conclusions The amplitude of accommodation of the dominant eye is not significantly enhanced,and less accommodative lag and better accommodative facility also are found in the demonstrate eye in myopia adults with low anisometropia.

[Bone marrow stem cell-derived astrocytes are involved in glia limitans formation in rats after brain injury].

OBJECTIVE: To investigate the involvement of bone marrow stem cell-derived astrocytes (BMDSCs) in the formation of glia limitans after brain injury. METHODS: In a female SD rat model of brain injury, green fluorescence protein (GFP)-labeled BMDSCs from male SD rats were transplanted via the caudal vein 24 h after the injury. The rats were sacrificed at 2, 4 and 8 weeks after the transplantation, and immunohistochemistry for glial fibrillary acidic protein (GFAP) was performed to observe the astrocytes. The fluorescence emitted by GFP was observed to identify the presence of the bone marrow-derived stem cells, and the GFAP(+)/GFP(+) cells in the glia limitnas were detected under fluorescence microscopy. RESULTS The GFAP(+)/GFP(+) cells were found in the glia limitans between the brain lesion and normal brain tissue. CONCLUSION: Bone marrow stem cell-derived astrocytes is involved in glia limitans formation after brain injury, which can be of significance in brain injury recovery and implantation of engineered materials.

RNA interference mediated silencing of alpha-synuclein in MN9D cells and its effects on cell viability.

OBJECTIVE: To silence the expression of alpha-synuclein in MN9D dopaminergic cells using vector mediated RNA interference (RNAi) and examined its effects on cell proliferation and viability. METHODS: We identified two 19-nucleotide stretches within the coding region of the alpha-synuclein gene and designed three sets of oligonucleotides to generate double-stranded (ds) oligos. The ds oligos were inserted into the pENTR/H1/TO vector and transfected into MN9D dopaminergic cells. alpha-Synuclein expression was detected by RT-PCR, real-time PCR, immunocytochemistry staining and Western blot. In addition, we measured cell proliferation using growth curves and cell viability by 3-(4, 5)-dimethylthiahiazo (-z-y1)-3, 5-di- phenytetrazoliumromide (MTT). RESULTS: The mRNA and protein levels of alpha-synuclein gene were significantly down-regulated in pSH2/alpha-SYN-transfected cells compared with control MN9D and pSH/CON-transfected MN9D cells, while pSH1/alpha-SYN-transfected cells showed no significant difference. Silencing alpha-synuclein expression does not affect cell proliferation but may decrease cell viability. CONCLUSION: Our results demonstrated pSH2/alpha-SYN is an effective small interfering RNA (siRNA) sequence and potent silencing of mouse alpha-synuclein expression in MN9D cells by vector-based RNAi, which provides the tools for studying the normal function of alpha-synuclein and examining its role in Parkinson's disease (PD) pathogenesis. alpha-Synuclein may be important for the viability of MN9D cells, and loss of alpha-synuclein may induce cell injury directly or indirectly.

Astrocytes protect MN9D neuronal cells against rotenone-induced oxidative stress by a glutathione-dependent mechanism.

Astrocytes maintain homeostasis of neuronal microenvironment, provide metabolic and trophic support to neurons and modulate neuronal responses to injury. Rotenone specifically inhibits mitochondrial complex I, and long exposure to rotenone may increase the risk for Parkinson's disease (PD) and cause Parkinsonism. However, little is known about the role of astrocytes in the process of rotenone-induced dopaminergic neuron injury. In order to investigate this issue, we used MN9D cells as a cell model of dopaminergic neurons and rotenone as a toxin to initiate mitochondrial deficiency. MN9D cells treated with the normal medium or astrocyte-conditioned medium (ACM) were exposed to different concentrations of rotenone for different time followed by cell viability measurement by MTT assay. Besides, various concentrations of ACM and temporally different treatments were devised to evaluate protective efficiency of ACM. Growth curve of cells in the normal medium or ACM was continuously assessed by cell counting for 8 d. The influence of rotenone and ACM on cellular oxidative stress was determined by DCFH-DA staining followed by flow cytometric analysis. Glutathione (GSH) content after treatment of ACM or rotenone was measured by GSH assay kit. Our results showed that rotenone decreased viability of MN9D cells in a dose-dependent manner and ACM treatment significantly attenuated rotenone toxicity at each concentration. No significant difference in growth rate was observed between the normal medium and ACM treatment. Four concentrations of ACM, namely 1/3ACM, 1/2ACM, 2/3ACM and pure ACM, all displayed protection, increasing cell viability to (124.15+/-0.79)%, (126.59+/-0.82) %, (125.84+/-0.61) % and (117.15+/-1.63) % of the cells exposed directly to rotenone, respectively. Treatment with ACM through the whole experiment except the initial 24 h, 24 h before or at the same time of rotenone addition all exerted protective effects, with cell viability being (110.11+/-2.52)%, (113.30+/-2.36) %, (114.42+/-2.00)% of the cells exposed directly to rotenone, respectively. Conversely, ACM treatment 12 h after rotenone addition had no protective effect, with cell viability being (102.54+/-1.36)% of the cells exposed directly to rotenone. Moreover, ACM treatment up-regulated GSH level in MN9D cells nearly twofold. Incubation with 100 nmol/L rotenone for 24 h depleted GSH level by nearly two thirds of the control, but ACM treatment mitigated the drop of GSH level, maintaining its content at (147.83+/-0.63)% of the control. Consistent with GSH change, rotenone administration resulted in a positive rate of 96.24% of DCF staining, implying a great extent of oxidative stress, whereas treatment with ACM reduced the extent of oxidative stress to a positive rate of 78.31%. Taken together, these findings suggest that astrocytes protect MN9D cells from oxidative stress caused by rotenone, and GSH partially accounts for the protection. Therefore, astrocytes may play a protective role in the process of PD.

[Overexpression of alpha-synuclein in SH-SY5Y cells partially protected against oxidative stress induced by rotenone].

Both genetic and environmental factors are involved in the pathogenesis of Parkinsonos disease (PD). Epidemiological studies showed that environmental factors shared with the common mechanisms of resulting in alpha-synuclein aggregation by inhibiting complex I of mitochondria and leading to oxidative stress. To investigate the relationship between alpha-synuclein and oxidative stress, we used human dopaminergic SH-SY5Y cells transfected with alpha-synuclein-enhanced green fluorescent protein (EGFP). alpha-synuclein gene expression was determined by immunocytochemistry and real-time quantitative PCR. Both SH-SY5Y and alpha-synuclein overexpressed SH-SY5Y (SH-SY5Y/Syn) cells were treated with various concentrations of rotenone for different time. Cell viability and oxidative stress were detected by MTT assay and DCF assay. Superoxide dismutase (SOD) activity was assessed with xanthine peroxidase method. Cell apoptosis was detected with flow cytometry. Results showed that alpha-synuclein gene was constantly overexpressed in SH-SY5Y/Syn cells. After treatment with rotenone, both cell viability and complex I activity in these cells were reduced in a concentration-dependent manner. Oxidative stress was also found in these cells. Compared with SH-SY5Y cells, SOD activity in SH-SY5Y/Syn cells was increased distinctly (P<0.05) and alpha-synuclein significantly attenuated rotenone-induced cell apoptosis. These results suggest that the alpha-synuclein overexpression in SH-SY5Y cells has a tendency to partially resist oxidative stress induced by rotenone and this response may assist cell survival.

[Protective effect of maternal immunoglobulin G against NMDA-induced neurotoxicity on hippocampus neurons].

OBJECTIVE: To investigate possible protective effect of maternal immunoglobulin G (IgG) against N-methyl-D-aspartate-mediated neurotoxicity on primary-cultured rat hippocampal neurons and the mechanism of the effect. METHODS: An in vitro system had been developed for the study of hippocampal neurons. Intracellular lactic dehydrogenase (LDH) release was used as a marker to measure the rates of neuronal damage. The cells were stained with Trypan blue to measure the rate of neuronal death. RESULTS: N-methyl-D-aspartate (NMDA) at a concentration of 50 micromol/L resulted in increased release of LDH and the cell mortality (P < 0.01, respectively). Maternal IgG of different concentration (10 mg/L, 100 mg/L) inhibited NMDA-induced intracellular LDH release (P < 0.01, respectively) and cell mortality (P < 0.05, 0.01, respectively), and larger dose had stronger effect (P < 0.05). CONCLUSIONS: Maternal IgG had protective effect on primary-cultured rat hippocampal neurons injured by NMDA and the effect was dose-dependent.

[Maternal factors affecting development of early mouse embryos].

In vertebrates, oocytes undergo a series of maturation steps, arresting at metaphase II, and can then be fertilized by a sperm. Fertilization initiates molecular events that lead to the activation of early embryonic development. Fertilized oocytes or activated reconstituted embryos then activate the zygotic genome, a crucial event that initiates early embryonic development. The functions of the maternal factors derived from oocytes are different at various mouse embryonic developmental stages. Mouse zygotic genome is activated at the two-cell stage which implies that embryonic development is transferred from the oocyte itself to the embryo. Sometimes mouse embryos are blocked at the two-cell stage, for which the mechanism is not clear. So exploring the functions of some maternal factors in the two-cell stage embryos may help us to understand the potential reasons for early embryonic development failure. Reprogramming a foreign and terminally differentiated somatic nucleus by transferring it to the enucleated oocyte cytoplasm triggers epigenetic changes that eventually lead to the birth of a viable animal. This indicates the oocyte cytoplasm plays a critical role in the development of reconstructed embryos.

The assays of activities and function of TH, AADC, and GCH1 and their potential use in ex vivo gene therapy of PD.

In the past decades, there have been numerous studies in the gene therapy for Parkinson's disease (PD), especially in delivering genes of enzymes for dopamine (DA) synthesis. Gene therapy in PD appears to be at the brink of the clinical study phase. However, there are many questions that need to be solved before this approach can be contemplated clinically, especially the question about the control of DA production because too much DA could cause toxicity. Until recently, few studies have investigated the relation between DA production and PD improvement and respective expressed human tyrosine hydroxylase (hTH), human GTP-cyclohydrolase 1 (hGCH1), and human aromatic acid decarboxylase (hAADC) in ex vivo gene therapy for PD. Now, we have developed a simple, fast, and reliable method to assay the activities of TH and AADC and have provided the possibility of ex vivo gene therapy for PD by genetically modifying cells with separate hTH, hGCH1, and hAADC genes. Using the method, we found though hTH, hGCH1, and hAADC genes were expressed, respectively, they could fulfil the function of DA synthesis by incubating together in vitro, and more DA was synthesized in vitro when hTH, hGCH1, and hAADC genes were expressed together rather than hTH and hAADC genes expressed or hTH expressed. The result suggests that we could easily control DA production in ex vivo gene therapy before transplantation. By combining this method and microdialysis, we also could further investigate the DA production in vitro and in vivo and then decide the optimal number and ratio of different transduced cells to improve the therapy of PD. Thus, the method has potential use in ex vivo gene therapy of PD.

[Gene therapy of tyrosine hydroxylase, aromatic L-amino acid decarboxylase, and GTP cyclohydrolase genes in rat model of Parkinson's disease].

OBJECTIVE: To detect the expression and function of enzyme genes involved in biosynthetic pathway for dopamine in vitro and assess their effect in rat model of Parkinson's disease. METHODS: Cos7 cells were transfected with separate adeno-associated virus (AAV) expressing tyrosine hydroxylase (TH) gene, aromatic L-amino acid decarboxylase (AADC) gene and GTP cyclohydrolase I (GCH-I) gene. The expression and function of the three genes were detected by methods of immunohistochemistry, in situ hybridization and high performance liquid chromatograph and electrochemical detection (HPLC-ECD). Gene engineered cells were sequentially transplanted into the striatum of 6-hydroxy-dopamine-leisioned Parkinsonian rat by stereotaxic instrastriatal injection. The asymmetric rotations of these rats after apomorphine administration were detected every week after transplantation. 10 weeks after grafting, the animals were sacrificed and the dopamine produced in the striatum was detected by HPLC-ECD. RESULTS: In vitro experiments showed that the three genes were high expressed in Cos7 cells. When Cos7 cells expressing TH, AADC and GCH-I were cocultured, they produced large amount of dopamine in the condition of existance of L-tyrosine. Furthermore, triple genes therapy resulted in greater dopamine production in the striatum of Parkinsonian rats and improved the rotational behavior of the rats more efficiently than did single gene therapy. However, the production of dopamine in the rats with triple genes therapy is no more than double genes therapy. CONCLUSION: For gene therapy in Parkinson's disease, the amount of target genes to be used should be determined by the level of doperminergic neurons damaged. In the present study, the efficiency of multiple genes therapy is significantly better than that of single gene therapy.

[Differentiation of bone marrow-derived stem cells in injured rat brain tissue].

OBJECTIVE: To investigate the differentiation of bone marrow-derived stem cells (BMDSCs) migrated from blood circulation and resided in the injured brain tissue. METHODS: Brain injury model was established by iridectomy in the right cerebral cortex of female SD rats. Twenty-four hours after brain injury, the female rats received the implantation of green fluorescence protein (GFP)-labeled BMDSCs from male SD rats and were sacrificed at 2, 4 and 8 weeks after the implantation. Fluorescent immunohistochemistry for CD11b and glial fibrillary acidic protein (GFAP) on the brain sections was used to detect the GFP-positive cells. RESULTS: One week after the transplantation of the GFP-labeled BMDSCs, 3.53% of the peripheral blood white cells were GFP-positive; at 4 weeks and 8 weeks, a significant number of GFP-positive cells were found at the injury sites, some of which expressed CD11b and others expressed GFAP. CONCLUSION: GFP-labeled BMDSCs can migrate to the injured brain tissue and differentiate into cells that express microglia- and astrocytes-specific antigens.