N6-methyladenosine (m6A) depletion regulates pluripotency exit by activating signaling pathways in embryonic stem cells.

N6-methyladenosine (m6A) deposition on messenger RNA (mRNA) controls embryonic stem cell (ESC) fate by regulating the mRNA stabilities of pluripotency and lineage transcription factors (TFs) [P. J. Batista et al., Cell Stem Cell 15, 707-719 (2014); Y. Wang et al., Nat. Cell Biol. 16, 191-198 (2014); and S. Geula et al., Science 347, 1002-1006 (2015)]. If the mRNAs of these two TF groups become stabilized, it remains unclear how the pluripotency or lineage commitment decision is implemented. We performed noninvasive quantification of Nanog and Oct4 TF protein levels in reporter ESCs to define cell-state dynamics at single-cell resolution. Long-term single-cell tracking shows that immediate m6A depletion by Mettl3 knock-down in serum/leukemia inhibitory factor supports both pluripotency maintenance and its departure. This is mediated by differential and opposing signaling pathways. Increased FGF5 mRNA stability activates pErk, leading to Nanog down-regulation. FGF5-mediated coactivation of pAkt reenforces Nanog expression. In formative stem cells poised toward differentiation, m6A depletion activates both pErk and pAkt, increasing the propensity for mesendodermal lineage induction. Stable m6A depletion by Mettl3 knock-out also promotes pErk activation. Higher pErk counteracts the pluripotency exit delay exhibited by stably m6A-depleted cells upon differentiation. At single-cell resolution, we illustrate that decreasing m6A abundances activates pErk and pAkt-signaling, regulating pluripotency departure.

HP1c regulates development and gut homeostasis by suppressing Notch signaling through Su(H).

Notch signaling and epigenetic factors are known to play critical roles in regulating tissue homeostasis in most multicellular organisms, but how Notch signaling coordinates with epigenetic modulators to control differentiation remains poorly understood. Here, we identify heterochromatin protein 1c (HP1c) as an essential epigenetic regulator of gut homeostasis in Drosophila. Specifically, we observe that HP1c loss-of-function phenotypes resemble those observed after Notch signaling perturbation and that HP1c interacts genetically with components of the Notch pathway. HP1c represses the transcription of Notch target genes by directly interacting with Suppressor of Hairless (Su(H)), the key transcription factor of Notch signaling. Moreover, phenotypes caused by depletion of HP1c in Drosophila can be rescued by expressing human HP1γ, suggesting that HP1γ functions similar to HP1c in Drosophila. Taken together, our findings reveal an essential role of HP1c in normal development and gut homeostasis by suppressing Notch signaling.

SIRT1 Mediates H2S-Ameliorated Diabetes-Associated Cognitive Dysfunction in Rats: Possible Involvement of Inhibiting Hippocampal Endoplasmic Reticulum Stress and Synaptic Dysfunction.

Diabetes-associated cognitive dysfunction (DACD) characterized by hippocampal injury increases the risk of major cerebrovascular events and death. Endoplasmic reticulum (ER) stress and synaptic dysfunction play vital roles in the pathological process. At present, no specific treatment exists for the prevention and/or the therapy of DACD. We have recently reported that hydrogen sulfide (H2S) exhibits therapeutic potential for DACD, but the underlying mechanism has not been fully elucidated. Silent information regulator 1 (SIRT1) has been shown to play a role in regulating the progression of diabetes and is also indispensable for memory formation and cognitive performance. Hence, the present study was performed to explore whether SIRT1 mediates the protective effect of H2S on streptozotocin (STZ)-induced cognitive deficits, an in vivo rat model of DACD, via inhibiting hippocampal ER stress and synaptic dysfunction. The results showed that administration of NaHS (an exogenous H2S donor) increased the expression of SIRT1 in the hippocampus of STZ-induced diabetic rats. Then, results proved that sirtinol, a special blocker of SIRT1, abrogated the inhibition of NaHS on STZ-induced cognitive deficits, as appraised by Morris water maze test, Y-maze test, and Novel object recognition behavioral test. In addition, administration of NaHS eliminated STZ-induced ER stress as evidenced by the decreases in the expressions of ER stress-related proteins including glucose-regulated protein 78, C/EBP homologous protein, and cleaved caspase-12 in the hippocampus, while these effects of NaHS were also reverted by sirtinol. Furthermore, the NaHS-induced up-regulation of hippocampal synapse-related protein (synapsin-1, SYN1) expression in STZ-induced diabetic rats was also abolished by sirtinol. Taken together, these results demonstrated that SIRT1 mediates the protection of H2S against cognitive dysfunction in STZ-diabetic rats partly via inhibiting hippocampal ER stress and synaptic dysfunction.

Formaldehyde induces ferritinophagy to damage hippocampal neuronal cells.

Formaldehyde (FA) causes neurotoxicity and contributes to the occurrence of neurodegenerative diseases. However, the mechanism of FA-induced neurotoxicity has not been fully elucidated. Ferritinophagy, an autophagy process of ferritin mediated by the nuclear receptor coactivator 4 (NCOA4), is a potential mechanism of neurotoxicity. In this study, we explored whether ferritinophagy is associated with the neurotoxicity of FA. Our results showed that FA (50, 100, 200 µM; 24 h) exposure upregulated ferritinophagy in the mouse hippocampal neuronal HT22 cells, which was evidenced by the upregulated autophagic flux, the increased colocalizations of NCOA4 with ferritin heavy chain (FTH1) and NCOA4 with microtubule-associated protein 1 light chain-3B (LC3B), the augmented expression of NCOA4, and the reduced content of FTH1. We also found that FA (0.1, 1, and 10 µmol, i.c.v., 7d) administration boosted ferritinophagy in the hippocampus of Sprague-Dawley (SD) rats, which was demonstrated by the accumulated autophagosomes, the increased expressions of LC3II/I and NCOA4, and the decreased contents of p62 and FTH1 in the hippocampus. Further, we confirmed that inhibition of ferritinophagy by silencing the expression of NCOA4 decreased FA-induced toxic damage in HT22 cells. These results indicated that FA induces neurotoxicity by promoting ferritinophagy. Our findings suggest a potential mechanism insight into the FA-induced neurotoxicity, which in turn provides a new thought for the treatment of FA-related neurodegenerative diseases.

Histone H3K27 methylation modulates the dynamics of FANCD2 on chromatin to facilitate NHEJ and genome stability.

Dysregulation of the homeostatic balance of histone H3 di- and tri-methyl lysine 27 (H3K27me2/3) levels caused by the mis-sense mutation of histone H3 (H3K27M) is reported to be associated with various types of cancers. In this study, we found that reduction in H3K27me2/3 caused by H3.1K27M, a mutation of H3 variants found in patients with diffuse intrinsic pontine glioma (DIPG), dramatically attenuated the presence of 53BP1 (also known as TP53BP1) foci and the capability of non-homologous end joining (NHEJ) in human dermal fibroblasts. H3.1K27M mutant cells showed increased rates of genomic insertions/deletions and copy number variations, as well as an increase in p53-dependent apoptosis. We further showed that both hypo-H3K27me2/3 and H3.1K27M interacted with FANCD2, a central player in the choice of DNA repair pathway. H3.1K27M triggered the accumulation of FANCD2 on chromatin, suggesting an interaction between H3.1K27M and FANCD2. Interestingly, knockdown of FANCD2 in H3.1K27M cells recovered the number of 53BP1-positive foci, NHEJ efficiency and apoptosis rate. Although these findings in HDF cells may differ from the endogenous regulation of the H3.1K27M mutant in the specific tumor context of DIPG, our results suggest a new model by which H3K27me2/3 facilitates NHEJ and the maintenance of genome stability.This article has an associated First Person interview with the first author of the paper.

Hydrogen Sulfide Inhibits Homocysteine-Induced Neuronal Senescence by Up-Regulation of SIRT1.

Homocysteine (Hcy) accelerates neuronal senescence and induces age-related neurodegenerative diseases. Silence signal regulating factor 1 (SIRT1) prolongs lifespan and takes neuroprotective effects. We have previously demonstrated that hydrogen sulfide (H2S) prevents Hcy-induced apoptosis of neuronal cells and has neuroprotective effect. In the present work, we aimed to investigate whether H2S protects HT22 cells against Hcy-induced neuronal senescence and whether SIRT1 mediates this role of H2S. We found that Hcy induced cellular senescence in HT22 cells, as determined by ß-galactosidase staining, expressions of P16INK4a, P21CIPL, and trypan blue Staining, which are the markers of cellular senescence. However, sodium hydrosulfide (NaHS, the donor of H2S) significantly reversed Hcy-induced cellular senescence. Interestingly, NaHS not only up-regulated the expression of SIRT1 in HT22 cells but also reversed Hcy-downregulated the expression of SIRT1 in HT22 cells. Furthermore, we found that pretreatment with Sirtinol (an inhibitor of SIRT1) markedly reversed the protection of NaHS against Hcy-induced HT22 cells senescence and apoptosis. Our findings illustrated that H2S protects HT22 cells against Hcy-induced senescence by up-regulating SIRT1.

Histone H2B monoubiquitination is a critical epigenetic switch for the regulation of autophagy.

Autophagy is an evolutionarily conserved cellular process that primarily participates in lysosome-mediated protein degradation. Although autophagy is a cytoplasmic event, how epigenetic pathways are involved in the regulation of autophagy remains incompletely understood. Here, we found that H2B monoubiquitination (H2Bub1) is down-regulated in cells under starvation conditions and that the decrease in H2Bub1 results in the activation of autophagy. We also identified that the deubiquitinase USP44 is responsible for the starvation-induced decrease in H2Bub1. Furthermore, the changes in H2Bub1 affect the transcription of genes involved in the regulation of autophagy. Therefore, this study reveals a novel epigenetic pathway for the regulation of autophagy through H2Bub1.

The association between S100A13 and HMGA1 in the modulation of thyroid cancer proliferation and invasion.

BACKGROUND: S100A13 and high mobility group A (HMGA1) are known to play essential roles in the carcinogenesis and progression of cancer. However, the correlation between S100A13 and HMGA1 during cancer progression is not yet well understood. In this study, we determined the effects of S100A13 on HMGA1 expression in thyroid cancer cells and examined the role of HMGA1 in thyroid cancer progression. METHODS: Stable ectopic S100A13 expression TT cellular proliferation was evaluated by nude mice xenografts assays. The effect of lentivirus-mediated S100A13 knockdown on thyroid cancer cellular oncogenic properties were evaluated by MTT, colony formation assays and transwell assays in TPC1 and SW579 cells. The effect of siRNA-mediated HMGA1 knockdown on thyroid cancer cellular proliferation and invasion were evaluated by MTT, colony formation assays and transwell assays. The tissue microarray was performed to investigate the correlation between S100A13 and HMGA1 expression in tumor tissues. RESULTS: The ectopic expression of S100A13 could increase tumor growth in a TT cell xenograft mouse model. Moreover, lentivirus-mediated S100A13 knockdown led to the inhibition of cellular oncogenic properties in thyroid cancer cells, and HMGA1 was found to be involved in the effect of S100A13 on thyroid cancer growth and invasion. Furthermore, siRNA-mediated HMGA1 knockdown was proved to inhibit the growth of TPC1 cells and invasive abilities of SW579 cells. Clinically, it was revealed that both S100A13 and HMGA1 showed a higher expression levels in thyroid cancer cases compared with those in matched normal thyroid cases (P = 0.007 and P = 0.000); S100A13 and HMGA1 expressions were identified to be positively correlated (P = 0.004, R = 0.316) when analyzed regardless of thyroid cancer types. CONCLUSIONS: This is the first report for the association between HMGA1 and S100A13 expression in the modulation of thyroid cancer growth and invasion. Those results would provide an essential insight into the effect of S100A13 on carcinogenesis of thyroid tumor, rending S100A13 to be potential biological marker for the diagnosis of thyroid cancer.

Redox-active quinones induces genome-wide DNA methylation changes by an iron-mediated and Tet-dependent mechanism.

DNA methylation has been proven to be a critical epigenetic mark important for various cellular processes. Here, we report that redox-active quinones, a ubiquitous class of chemicals found in natural products, cancer therapeutics and environment, stimulate the conversion of 5 mC to 5 hmC in vivo, and increase 5 hmC in 5751 genes in cells. 5 hmC increase is associated with significantly altered gene expression of 3414 genes. Interestingly, in quinone-treated cells, labile iron-sensitive protein ferritin light chain showed a significant increase at both mRNA and protein levels indicating a role of iron regulation in stimulating Tet-mediated 5 mC oxidation. Consistently, the deprivation of cellular labile iron using specific chelator blocked the 5 hmC increase, and a delivery of labile iron increased the 5 hmC level. Moreover, both Tet1/Tet2 knockout and dimethyloxalylglycine-induced Tet inhibition diminished the 5 hmC increase. These results suggest an iron-regulated Tet-dependent DNA demethylation mechanism mediated by redox-active biomolecules.

Simhypo-sand: a simple hypoplastic model for granular materials and SPH implementation.

This paper introduces a new hypoplastic model characterized by a simple and elegant formulation. It requires only 7 material parameters to depict salient mechanical behaviors of granular materials. The numerical implementation employs an explicit integration method, enhanced by a best-fit stress correction algorithm in a smoothed particle hydrodynamics code. The performance of this model in capturing soil behavior across a range of scenarios is demonstrated by conducting various numerical tests, including triaxial and simple shear at low strain rates, as well as granular collapse, rigid penetration and landslide process at high strain rates.

Single-cell m6A mapping in vivo using picoMeRIP-seq.

Current N6-methyladenosine (m6A) mapping methods need large amounts of RNA or are limited to cultured cells. Through optimized sample recovery and signal-to-noise ratio, we developed picogram-scale m6A RNA immunoprecipitation and sequencing (picoMeRIP-seq) for studying m6A in vivo in single cells and scarce cell types using standard laboratory equipment. We benchmark m6A mapping on titrations of poly(A) RNA and embryonic stem cells and in single zebrafish zygotes, mouse oocytes and embryos.

Practical Guidance for the Use of Patisiran in the Management of Polyneuropathy in Hereditary Transthyretin-Mediated Amyloidosis.

Variant transthyretin amyloidosis (ATTRv) is an autosomal dominant inherited genetic disorder that affects 5000-10,000 people worldwide. It is caused by mutations in the transthyretin (TTR) gene and results in amyloid deposition in a variety of organs due to abnormal accumulation of TTR protein fibrils. Although this is a multisystem disorder, the heart and peripheral nerves are the preferentially affected organs. Over 150 TTR gene mutations have been associated with this disease and the clinical phenotype can vary significantly. Severe forms of the disorder can be fatal. Fortunately, the oligonucleotide-based therapy era has resulted in the development of several novel treatment options. Patisiran is a small interfering RNA (siRNA) encapsulated in a lipid nanoparticle that targets both mutant and wild-type TTR and results in significant reductions of the TTR protein in the serum and in tissue deposits. Patisiran has been approved for treatment of adults with polyneuropathy due to hereditary TTR-mediated amyloidosis in both the United States (US) and European Union (EU). In this review, we will discuss the development of patisiran, the clinical trials that lead to treatment approval, and provide guideline parameters for use in clinical practice.  .

Association between obstructive sleep apnea and floppy eyelid syndrome: A systematic review and metaanalysis.

RATIONALE: Obstructive sleep apnoea (OSA) has been linked to various ocular disorders, including floppy eyelid syndrome (FES). Previous studies have hypothesised the underlying association between the 2 , but results are currently still inconclusive. OBJECTIVE: To investigate the association between OSA and FES. METHODS: Four databases (Pubmed, Embase, Scopus, and Cochrane Library) were searched from inception until 28 February 2022 for observational studies and randomized controlled trials assessing the association between OSA and FES. Two reviewers selected studies, extracted data, graded the risk of bias using the Newcastle-Ottawa scale and the quality of assessment using the Grading of Recommendations Assessment, Development, and Evaluation system. Random-effects models were used to metaanalyze the associations. RESULTS: Twelve studies were included in the systematic review, of which nine were suitable for metaanalysis, with a combined cohort of 1,109 patients. Risk of bias was low to moderate. The overall analysis showed a significant positive association between OSA and FES (OR = 1.89, 95% CI = 1.27-2.83, I 2 = 44%). Further analysis revealed that the more severe the OSA was, the higher the risk of developing FES. Patients with severe OSA had the nominally highest risk of developing FES (OR = 3.06, 95% CI = 1.62-5.78, I 2 = 0%), followed by moderate OSA (OR = 2.53, 95% CI = 1.29-4.97, I 2 = 0%), and patients with mild OSA had the lowest risk (OR = 1.76, 95% CI = 0.85-3.62, I 2 = 0%). CONCLUSION: Our metaanalysis reports a positive association between OSA and FES, with increasing severity of OSA correlating with a significantly higher risk of FES. More longitudinal studies with sufficient duration of follow-up are needed to better characterise the relationship between OSA and FES.

Obstructive sleep apnoea and glaucoma: a systematic review and meta-analysis.

INTRODUCTION: Obstructive sleep apnoea (OSA) has been thought to be associated with glaucoma, however there are many conflicting studies on this topic. With many new studies having been published since the previous meta-analysis, we believe it is important to clarify this association. Hence, in this study we meta-analyse the recent literature regarding the association between OSA and glaucoma. METHODS: Pubmed, Embase, Scopus and Cochrane Library were searched from inception till the 28th February 2022 for observational as well as cross-sectional studies examining the association between OSA and glaucoma. Two reviewers selected studies, extracted data, graded the quality of included non-randomized studies using the Newcastle-Ottawa scale. The overall quality of evidence was assessed using GRADE. Random-effects models were used to meta-analyse the maximally covariate- adjusted associations. RESULTS: 48 studies were included in our systematic review, with 46 suitable for meta-analysis. Total study population was 4,566,984 patients. OSA was associated with a higher risk of glaucoma (OR 3.66, 95% CI 1.70 to 7.90, I2 = 98%, p < 0.01). After adjustment for various important confounders including age, gender and patient comorbidities such as hyperlipidaemia, hypertension, cardiovascular diseases and diabetes, patients with OSA had up to 40% higher odds of glaucoma. Substantial heterogeneity was eliminated through subgroup and sensitivity analyses after consideration of glaucoma subtype, OSA severity and adjustment for confounders. CONCLUSIONS: In this meta-analysis, OSA was associated with higher risk of glaucoma, as well as more severe ocular findings characteristic of the glaucomatous disease process. We suggest more clinical studies looking into the effects of OSA treatment on the progression of glaucoma to help clinical decision making for patients.

Incorporation of a histone mutant with H3K56 site substitution perturbs the replication machinery in mouse embryonic stem cells.

Sense mutations in several conserved modifiable sites of histone H3 have been found to be strongly correlated with multiple tissue-specific clinical cancers. These clinical site mutants acquire a distinctively new epigenetic role and mediate cancer evolution. In this study, we mimicked histone H3 at the 56th lysine (H3K56) mutant incorporation in mouse embryonic stem cells (mESCs) by lentivirus-mediated ectopic expression and analyzed the effects on replication and epigenetic regulation. The data show that two types of H3K56 mutants, namely H3 lysine 56-to-methionine (H3K56M) and H3 lysine 56-to-alanine (H3K56A), promote replication by recruiting more minichromosome maintenance complex component 3 and checkpoint kinase 1 onto chromatin compared with wild-type histone H3 and other site substitution mutants. Under this condition, the frequency of genomic copy number gain in H3K56M and H3K56A cells globally increases, especially in the Mycl1 region, a known molecular marker frequently occurring in multiple malignant cancers. Additionally, we found the disruption of H3K56 acetylation distribution in the copy-gain regions, which indicates a probable epigenetic mechanism of H3K56M and H3K56A. We then identified that H3K56M and H3K56A can trigger a potential adaptation to transcription; genes involved in the mitogen-activated protein kinase pathway are partially upregulated, whereas genes associated with intrinsic apoptotic function show obvious downregulation. The final outcome of ectopic H3K56M and H3K56A incorporation in mESCs is an enhanced ability to form carcinomas. This work indicates that H3K56 site conservation and proper modification play important roles in harmonizing the function of the replication machinery in mESCs.

Clinical Study on Efficiency of Using Traditional Direct Bonding or OrthGuide Computer-Aided Indirect Bonding in Orthodontic Patients.

Objective: This study aims to clinically investigate and compare the therapeutic effects and treatment cycle between traditional direct bonding and OrthGuide computer-aided indirect bonding in orthodontic treatment. Methods: Forty patients treated at the Department of Orthodontics, Beijing Rytime Dental Hospital between July 1, 2016, and December 31, 2019, were included. The patients were divided into a control group (n = 20, traditional direct bonding) and a test group (n = 20, OrthGuide computer-aided indirect bonding). The American Board of Orthodontics (ABO) measurement was performed on patients using Uceph cephalometric analysis software to compare intragroup and intergroup differences, and the treatment cycles of all patients were recorded. Results: After treatment, U1-NA (mm), ∠U1-SN (°), LL-EP (mm), and UL-EP (mm) in the control group were significantly lower than before treatment, and there was no significant difference in other ABO measurement indexes, while the test group showed no marked difference in all ABO measurements between pre- and posttreatment. Further, intergroup comparison showed no significant difference in ABO measurements in pre- and posttreatment between the two groups. The test group had a shorter treatment cycle than the control group, with an average treatment cycle of 21.20 ± 7.14 months in the control group and 17.17 ± 4.16 months in the test group. Conclusion: There was no significant difference in the therapeutic effects between the direct and indirect bonding techniques. However, OrthGuide computer-assisted indirect bonding demonstrated a significantly shorter treatment cycle and might be more efficient than traditional direct bonding.

Hydrogen Sulfide Attenuates the Cognitive Dysfunction in Parkinson's Disease Rats via Promoting Hippocampal Microglia M2 Polarization by Enhancement of Hippocampal Warburg Effect.

Identification of innovative therapeutic targets for the treatment of cognitive impairment in Parkinson's disease (PD) is urgently needed. Hydrogen sulfide (H2S) plays an important role in cognitive function. Therefore, this work is aimed at investigating whether H2S attenuates the cognitive impairment in PD and the underlying mechanisms. In the rotenone- (ROT-) established PD rat model, NaHS (a donor of H2S) attenuated the cognitive impairment and promoted microglia polarization from M1 towards M2 in the hippocampus of PD rats. NaHS also dramatically upregulated the Warburg effect in the hippocampus of PD rats. 2-Deoxyglucose (2-DG, an inhibitor of the Warburg effect) abolished NaHS-upregulated Warburg effect in the hippocampus of PD rats. Moreover, the inhibited hippocampal Warburg effect by 2-DG abrogated H2S-excited the enhancement of hippocampal microglia M2 polarization and the improvement of cognitive function in ROT-exposed rats. Our data demonstrated that H2S inhibits the cognitive dysfunction in PD via promoting microglia M2 polarization by enhancement of hippocampal Warburg effect.

Transient impact of prolonged versus repetitive stretch on hand motor control in chronic stroke.

BACKGROUND AND PURPOSE: The purpose of this study was to investigate the influence of prolonged and repetitive passive range of motion (PROM) stretching of the fingers on hand function in stroke survivors. PARTICIPANTS: Fifteen chronic stroke survivors with moderate to severe hand impairment took part in the study. METHOD: Participants underwent 3 experimental sessions consisting of 30 minutes of rest, prolonged, or repetitive stretching of the finger flexor muscles by a powered glove orthosis (X-Glove). Outcome measures, comprised of 3 selected tasks from the Graded Wolf Motor Function Test (GWMFT), grip strength, lateral pinch strength, and grip relaxation time, were recorded at the start and end of each session. Change in outcome score for each session was used for analysis. RESULTS: Data suggested a trend for improvement following stretching, especially for the repetitive PROM case. For one GWMFT task (lift washcloth), the effect of stretching condition on performance time approached a statistical significance (P = .015), with repetitive PROM stretching producing the greatest mean reduction. Similarly, repetitive stretching led to a 12% ± 16% increase in grip strength, although this change was not statistically different across groups (P = .356); and grip termination time was reduced, albeit non-significantly, by 66% ± 133%. CONCLUSION: Repetitive PROM stretching exhibited trends to be more effective than prolonged stretching for improving hand motor control. Although the results were highly variable and the effects are undoubtedly transient, an extended period of repetitive PROM stretching may prove advantageous prior to hand therapy sessions to maximize treatment.

Sez-6 may play an important role in neurite outgrowth through the PKCgamma signaling pathways.

Seizure-related gene 6 (sez-6) was originally identified in a study of pentylenetetrazole-treated cortical neurons. Further studies on the structure and expression pattern suggested that Sez-6 may play an important role in neuronal development and function. In the present study, PC12 cells were used as a model to investigate the role of Sez-6 in neurite outgrowth. After a period of NGF treatment, the expression of Sez-6 in PC12 cells was increased. When Sez-6 expression was suppressed by the addition of an effective short hairpin RNA (shRNA) plasmid, the neurite outgrowth was significantly inhibited. In addition, we detected the expression level of protein kinase Cgamma (PKCgamma), and found that the PKCgamma protein level was reduced in the differentiated PC12 cells but increased in PC12 cells lacking Sez-6. Taken together, our results indicate that Sez-6 acts on the neurite outgrowth of PC12 cells likely through the PKCgamma signaling pathways.

Electrodiagnostic Assessment of Motor Neuron Disease.

Motor neuron diseases involve degeneration of motor neurons in the brain (upper motor neurons), brain stem, and spinal cord (lower motor neurons). Symptoms vary depending on the degree of upper and lower neuron involvement, but progressive painless weakness is the predominant complaint. Motor neuron disease includes numerous specific disorders, including amyotrophic lateral sclerosis, spinal muscular atrophy, spinal bulbar muscular atrophy, and other inherited and acquired conditions. Abnormalities on nerve conduction studies, repetitive nerve stimulation, needle electromyography, and other electrodiagnostic techniques help to distinguish these disorders from each other, and from other disorders with progressive weakness.