Background RCS-rdy--P+ rat occur retinitis pigmentosa (PR) with the aging and development.To find OUt the retinal functional change using electrophysiological technique is useful for the further study of RCS-rdy--P+ rat. Ohjectlve The goal of this experiment was to investigate the dark-adapted electroretinogram (ERG) of RCS rats with aging. Methods The series of seotopic ERG were recorded in postnatal 21-,32-,37-,45-,60-day-old RCS-rdy--P+ rats respectively,and the age-matched RCS-rdy+-P+ rats were simultaneously recorded as control group.The ERG record was performed by a series of flash with RETI-scan system,gold-foil ring form cornea recording electrode and home-made stainless steel needle electrode.The use of animals complied with the Regulations of the Administration of Affair Concerning Experimental Animals by State Science and Technology Commission. Results Increase dark adaptation duration led to an ascended amplitude in ERG b-wave within 12 hours under the same light intensity,frequency and body temperature.Compared with the RCS-rdy+-P+ rats,the amplitudes of scotopic ERG a-wave and b-wave in RCS-rdy--P+ rats with postnatal 21 days age were apparently declined,showing significant difference between them(P<0.01).The implicit time of both RCS-rdy+-P+ rats and RCS-rdy--P+ rats were delayed, especially for the a-wave. The amplitudes of a-wave and b-wave were declined drastically with the growth of RCS-rdy--P+ rats and progression of their retinal degeneration, and the ERG responses were undetectable at the postnatal 60 days. Both the b-wave and a-wave amplitudes were lowered at P21-day RCS-rdy+-P+ rats and after that,significant increase amplitudes were noted till the P32-day rats. Thereafter, the b-wave amplitude and a-wave amplitude were stable from P32 d to P45 d,and much more ascending of b-wave and a-wave amplitudes was at P60 d RCS-rdy+-P+ rats. Conclusion RCS-rdy--P+ rats occur the retrogression of retinal function along with the ages growth. The scotopic ERG changes of RCS-rdy--P+ rats with aging is evidently different and is in accordance to the characteristics of the RP.

Background Channelrhodopsin-2 (ChR2)is a cation channel isolated from the eyespot of Chlamydomonas algae and has been used to control neuron activity.The light stimulation is a more precise fashion whether space or time than that of electrical,magnetic and ultrasound stimulation. Objective This study was to construct a replication deficient recombinant adenovirus cxpression vector of ChR2 and to determine its function.Methods Human embryo kidney 293 (HEK293) cell line was cultured and passaged in DF12 medium containing 10％ fetal bovine serum(FBS).The ChR2 gene was cloned at the downstream of cytomegalovirus(CMV)promoter of the adenoviral shuttle plasmid pSB291 in sense direction,and the resultant recombinant plasmid pSB291-hChR2- GFP was transfected into HEK293 cell together with plasmid pBHG lox ( deltaE1,3 ) containing adenoviral genome,then small amounts replication deficient recombinant adenovirus expression vector of ChR2 (Ad-ChR2) was obtained.Through amplification gradient centrifugation and dialysis,pure Ad-ChR2 was obtained.Visual cortex cells derived from 4 1-day-old clean Long Evans rats were primary cultured with serum-free culture media and infected by AdChR2.When expressing green fluorescencc,those cells received the stimulated of blue light with 460 nm.Patch clamp technique was applied to record an action potential. Results After purification and concentration,the titer of AdhCHR2 reached 7.9×1010 PFU/ml.Twenty-four hours after transfect of Ad-ChR2,HEK293 cell membrane showed the green fluorescence for the recombinant plasmid with green fluorescence protein under the inversed fluorescence microscope.The HEK293 cells change their shape from flat to round 13 days after transfected.The primary cultured visual cortex cells exhibited the green fluorescence 3-5 days after infected by Ad-ChR2.The action potentials evoked by blue light stimulation were recorded with patch clamp on those cells expressing green fluorescence. Conclusions Ad-ChR2 expressing vector is constructed successfully in this study.It is verified that Ad-ChR2 expressing vector can infect visual cortex cells with visual function.This result is very important for visual plasticity study.

Background Oscillatory potentials (OPs) of scotopic electroretinogram (ERG) plays an important role in the evaluation of visual function in multiple retinal diseases.However,the origin of OPs is uncompletely clear.It is essential to analyze the time domain and frequency domain components for the further study of OPs.Objective The present study was to investigate the change characteristics of frequency spectrum of scotopic OPs with age and stimulating intensity.Methods RCS-rdy+-p+rats with the ages of 21,25,32,35,37,46,60,90 days were selected iu this study and 3 rats for each.Scotopic flash ERG were recorded from all the rats with RETI-scan system.Gold-foil ring cornea recording electrode was used as the recording electrode and the steel needle electrode was used as the reference and earth electrode during the record.The intensity of stimulating light was set at-20,-10,-5,0 and 5 dB respectively.Data were output into the computer and processed by the software Matlab7.0.Results The principle frequency corresponding to maximum amplitude component was 80-120 Hz in the various ages of rats under the different stimulating conditions above.With the increase of the intensity of stimulating light,high frequency component (200-250 Hz) began to appear and the amplitudes showed a gradually raise upon the intensity of light.The major component was subdivided into two peaks at 0 dB stimulation.Further,the age affected the major frequency peak with the maximum value at 60-day-old rats and the minimum value at 25-day-old rats.Also,the pass-band width of main amplitude appeared to be maximal at 60-day-old rats and minimal at 25-day-old rats.Conclusions OPs in Rcsrdy+-p+ rats are influenced by stimulating intensity and agc.Stimulating intensity affects the amplitude and age lead to the change of distribution of primary frequency of OPs.It is possible to know the influences of the degeneration of rods and be helpful to diagnosis this kind of disease.

Background:Reduced expression of tripartite motif-containing 3 (TRIM3) has been reported to be involved in the pathogenesis of human glioblastoma.In our previous research,we found that TRIM3 expression was markedly reduced in human primary hepatocellular carcinoma (HCC) tissues and that low TRIM3 expression was associated with short survival of HCC patients.However,the role of TRIM3 in liver cancer remains unknown.This study aimed to investigate the function of TRIM3 in liver cancer cells.Methods:The protein levels of TRIM3 in five liver cancer cell lines (SK-Hep1,Hep3B,Huh7,HepG2,Bel-7402) and one normal liver cell line (L02) were detected with Western blotting.HepG2 and Bel-7402 cells with IowTRIM3 expression were infected with recombinant lentiviruses overexpressing TRIM3 (LV-TRIM3),whereas Huh7 and Hep3B cells with high TRIM3 expression were transfected with TRIM3-targeted small interfering RNA (siTRIM3).The functions of TRIM3 in the proliferation,colony formation,cell cycle,migration,invasion,and apoptosis of the above cell lines were examined.The effect of TRIM3 on tumor growth and metastases in nude mice was also investigated.Results:TRIM3 was overexpressed in HepG2 and Bel-7402 cells with LV-TRIM3 infection,which further reduced proliferation,colony formation,migration,and invasion of both cell lines.Cell cycle analysis showed thatTRIM3 overexpression induced G0/G1 phase arrest in HepG2 and Bel-7402 cells.Moreover,apoptosis was not increased in HepG2 or Bel-7402 cells overexpressing TRIM3.Contrarily,silencing TRIM3 expression in Huh7 and Hep3B cells by siTRIM3 led to significantly decreased percentages of both cells in the G0/G1 phase and promoted cell proliferation,colony formation,migration,and invasion.In vivo experiment results confirmed thatTRIM3 overexpression suppressed tumor growth and metastasis.Conclusions:TRIM3 plays a tumor-suppressing role in the regulation of liver cancer development by reducing cell proliferation through cell cycle arrest at the G0/G1 phase.

BACKGROUND AND PURPOSE: It is essential to develop a reliable predictive serum biomarker for Parkinson's disease (PD). The accumulation of alpha-synuclein (αSyn) and up-regulated expression of Rab35 participate in the etiology of PD. The purpose of this investigation was to determine whether the combined assessment of serum αSyn and Rab35 is a useful predictive biomarker for PD. METHODS: Serum levels of αSyn or Rab35 were determined in serum samples from 59 sporadic PD patients, 19 progressive supranuclear palsy (PSP) patients, 20 multiple system atrophy (MSA) patients, and 60 normal controls (NC). Receiver operating characteristics (ROC) curves were calculated to determine the diagnostic accuracy of αSyn or/and Rab35 in discriminating PD patients from NC or atypical parkinsonian patients. RESULTS: The levels of αSyn and Rab35 were increased in PD patients. The serum level of Rab35 was positively correlated with that of αSyn in PD patients. Compared to analyzing αSyn or Rab35 alone, the combined analysis of αSyn and Rab35 produced a larger area under the ROC curve and performed better in discriminating PD patients from NC, MSA patients, or PSP patients. When age was dichotomized at 55, 60, 65, or 70 years, the combined assessment of αSyn and Rab35 for classifying PD was better in the group below the cutoff age than in the group above the cutoff age. CONCLUSIONS: Combined assessment of serum αSyn and Rab35 is a better biomarker for discriminating PD patients from NC or atypical parkinsonian patients, and is a useful predictive biomarker for younger sporadic PD patients.
alpha-Synuclein ; Humans ; Multiple System Atrophy ; Parkinson Disease ; ROC Curve ; Supranuclear Palsy, Progressive

Distinct from the complementary inhibition mechanism through binding to the target with three-dimensional conformation of small molecule inhibitors, targeted protein degradation technology takes tremendous advantage of endogenous protein degradation pathway inside cells to degrade plenty of “undruggable” target proteins, which provides a novel route for the treatment of many serious diseases, mainly including proteolysis-targeting chimeras, lysosome-targeting chimeras, autophagy-targeting chimeras, antibody-based proteolysis-targeting chimeras, etc. Unlike proteolysis-targeting chimeras first found in 2001, which rely on ubiquitin-proteasome system to mainly degrade intracellular proteins of interest, lysosome-targeting chimeras identified in 2020, which was act as the fastly developing technology, utilize cellular lysosomal pathway through endocytosis mediated by lysosome-targeting receptor to degrade both extracellular and membrane proteins. As an emerging biomedical technology, nucleic acid-driven lysosome-targeting chimeras utilize nucleic acids as certain components of chimera molecule to replace with ligand to lysosome-targeting receptor or protein of interest, exhibiting broad application prospects and potential clinical value in disease treatment and drug development. This review mainly introduced present progress of nucleic acid-driven lysosome-targeting chimeras technology, including its basic composition, its advantages compared with antibody or glycopeptide-based lysosome-targeting chimeras, and focused on its chief application, in terms of the type of lysosome-targeting receptors. Most research about the development of nucleic acid-driven lysosome-targeting chimeras focused on those which utilized cation-independent mannose-6-phosphonate receptor as the lysosome-targeting receptor. Both mannose-6-phosphonate-modified glycopeptide and nucleic aptamer targeting cation-independent mannose-6-phosphonate receptor, even double-stranded DNA molecule moiety can be taken advantage as the ligand to lysosome-targeting receptor. The same as classical lysosome-targeting chimeras, asialoglycoprotein receptor can also be used for advance of nucleic acid-driven lysosome-targeting chimeras. Another new-found lysosome-targeting receptor, scavenger receptor, can bind dendritic DNA molecules to mediate cellular internalization of complex and lysosomal degradation of target protein, suggesting the successful application of scavenger receptor-mediated nucleic acid-driven lysosome-targeting chimeras. In addition, this review briefly overviewed the history of lysosome-targeting chimeras, including first-generation and second-generation lysosome-targeting chimeras through cation-independent mannose-6-phosphonate receptor-mediated and asialoglycoprotein receptor-mediated endocytosis respectively, so that a clear timeline can be presented for the advance of chimera technique. Meantime, current deficiency and challenge of lysosome-targeting chimeras was also mentioned to give some direction for deep progress of lysosome-targeting chimeras. Finally, according to faulty lysosomal degradation efficiency, more cellular mechanism where lysosome-targeting chimeras perform degradation of protein of interest need to be deeply explored. In view of current progress and direction of nucleic acid-driven lysosome-targeting chimeras, we discussed its current challenges and development direction in the future. Stability of natural nucleic acid molecule and optimized chimera construction have a great influence on the biological function of lysosome-targeting chimeras. Discovery of novel lysosome-targeting receptors and nucleic aptamer with higher affinity to the target will greatly facilitate profound advance of chimera technique. In summary, nucleic acid-driven lysosome-targeting chimeras have many superiorities, such as lower immunogenicity, expedient synthesis of chimera molecules and so on, in contrast to classical lysosome-targeting chimeras, making it more valuable. Also, the chimera technology provides new ideas and methods for biomedical research, drug development and clinical treatment, and can be used more widely through further research and optimization.