Subtle mutations in the SMN1 gene in Chinese patients with SMA: p.Arg288Met mutation causing SMN1 transcript exclusion of exon7

BACKGROUND: Proximal spinal muscular atrophy (SMA) is a common neuromuscular disorder resulting in death during childhood. Around 81 ~ 95% of SMA cases are a result of homozygous deletions of survival motor neuron gene 1 (SMN1) gene or gene conversions from SMN1 to SMN2. Less than 5% of cases showed rare subtle mutations in SMN1. Our aim was to identify subtle mutations in Chinese SMA patients carrying a single SMN1 copy. METHODS: We examined 14 patients from 13 unrelated families. Multiplex ligation-dependent probe amplification analysis was carried out to determine the copy numbers of SMN1 and SMN2. Reverse transcription polymerase chain reaction (RT-PCR) and clone sequencing were used to detect subtle mutations in SMN1. SMN transcript levels were determined using quantitative RT-PCR. RESULTS: Six subtle mutations (p.Ser8LysfsX23, p.Glu134Lys, p.Leu228X, p.Ser230Leu, p.Tyr277Cys, and p.Arg288Met) were identified in 12 patients. The p.Tyr277Cys mutation has not been reported previously. The p.Ser8LysfsX23, p.Leu228X, and p.Tyr277Cys mutations have only been reported in Chinese SMA patients and the first two mutations seem to be the common ones. Levels of full length SMN1 (fl-SMN1) transcripts were very low in patients carrying p.Ser8LysfsX23, p.Leu228X or p.Arg288Met compared with healthy carriers. In patients carrying p.Glu134Lys or p.Ser230Leu, levels of fl-SMN1 transcripts were reduced but not significant. The SMN1 transcript almost skipped exon 7 entirely in patients with the p.Arg288Met mutation. CONCLUSIONS: Our study reveals a distinct spectrum of subtle mutations in SMN1 of Chinese SMA patients from that of other ethnicities. The p.Arg288Met missense mutation possibly influences the correct splicing of exon 7 in SMN1. Mutation analysis of the SMN1 gene in Chinese patients may contribute to the identification of potential ethnic differences and enrich the SMN1 subtle mutation database

Effect of epidural block on surgical conditions during pediatric subumbilical laparoscopic surgery involving a supraglottic airway: a randomized clinical trial

BackgroundFew studies have examined the effect of epidural block on surgical conditions during pediatric subumbilical laparoscopic surgery involving a supraglottic airway (SGA). This study investigated the surgical condition scores for such procedures in cases where neuromuscular block, epidural block, or neither was used.MethodsA total of 150 patients aged 3–12 years undergoing laparoscopic orchiopexy with a ProSeal SGA device were randomly allocated to one of three groups: the control group (did not receive neuromuscular block and epidural block), the NMB group [received a neuromuscular block (train-of-four 1–2 twitches) using rocuronium], or the EDB group (received an epidural block using ropivacaine). The primary outcome was the quality of surgical conditions evaluated with the Leiden-Surgical Rating Scale by the blinded surgeon. The secondary outcome measures included intraoperative hemodynamic data (including mean arterial pressure and heart rate), the SGA device removal time, the PACU discharge time, the pain score in the PACU and intraoperative adverse events (including bradycardia, hypotension, peak airway pressure > 20 cmH2O, and poor or extremely poor surgical conditions occurred during the operation). Statistical analysis was performed with one-way analysis of variance, the Kruskal–Wallis test, the chi-square test or Fisher’s exact test. Bonferroni corrections for multiple comparisons were made for primary and secondary outcomes.ResultsSurgical condition scores were significantly higher in the NMB and EDB groups than in the control group (median difference: 0.8; 95% confidence interval [CI], 0.5–1.0; p < 0.0001; and median difference: 0.7; 95% CI, 0.5–0.8; p < 0.0001, respectively). Blood pressure and heart rate were significantly lower in the EDB group than in the other two groups (p < 0.0001 and p = 0.004). Patients in the EDB group had significantly lower pain scores during PACU than those in the other two groups (p < 0.0001). The sufentanil dose was lower in the EDB group than in the other two groups (p = 0.001).ConclusionEpidural block can improve surgical conditions during pediatric subumbilical laparoscopic surgery involving a SGA to a degree comparable to that with moderate neuromuscular block

Gut-brain axis: Mechanisms and potential therapeutic strategies for ischemic stroke through immune functions

After an ischemic stroke (IS) occurs, immune cells begin traveling to the brain and immune system from the gut and gastrointestinal tract, where most of them typically reside. Because the majority of the body’s macrophages and more than 70% of the total immune cell pool are typically found within the gut and gastrointestinal tract, inflammation and immune responses in the brain and immune organs require the mobilization of a large number of immune cells. The bidirectional communication pathway between the brain and gut is often referred to as the gut-brain axis. IS usually leads to intestinal motility disorders, dysbiosis of intestinal microbiota, and a leaky gut, which are often associated with poor prognosis in patients with IS. In recent years, several studies have suggested that intestinal inflammation and immune responses play key roles in the development of IS, and thus may become potential therapeutic targets that can drive new therapeutic strategies. However, research on gut inflammation and immune responses after stroke remains in its infancy. A better understanding of gut inflammation and immune responses after stroke may be important for developing effective therapies. This review discusses the immune-related mechanisms of the gut-brain axis after IS and compiles potential therapeutic targets to provide new ideas and strategies for the future effective treatment of IS

CERKL regulates autophagy via the NAD-dependent deacetylase SIRT1

<p>Macroautophagy/autophagy is an important intracellular mechanism for the maintenance of cellular homeostasis. Here we show that the <i>CERKL</i> (ceramide kinase like) gene, a retinal degeneration (RD) pathogenic gene, plays a critical role in regulating autophagy by stabilizing SIRT1. <i>In vitro</i> and <i>in vivo</i>, suppressing CERKL results in impaired autophagy. SIRT1 is one of the main regulators of acetylation/deacetylation in autophagy. In CERKL-depleted retinas and cells, SIRT1 is downregulated. ATG5 and ATG7, 2 essential components of autophagy, show a higher degree of acetylation in CERKL-depleted cells. Overexpression of SIRT1 rescues autophagy in CERKL-depleted cells, whereas CERKL loses its function of regulating autophagy in SIRT1-depleted cells, and overexpression of CERKL upregulates SIRT1. Finally, we show that CERKL directly interacts with SIRT1, and may regulate its phosphorylation at Ser27 to stabilize SIRT1. These results show that CERKL is an important regulator of autophagy and it plays this role by stabilizing the deacetylase SIRT1.</p

SnoRNAs from the filamentous fungus Neurospora crassa: structural, functional and evolutionary insights

<p>Abstract</p> <p>Background</p> <p>SnoRNAs represent an excellent model for studying the structural and functional evolution of small non-coding RNAs involved in the post-transcriptional modification machinery for rRNAs and snRNAs in eukaryotic cells. Identification of snoRNAs from <it>Neurospora crassa</it>, an important model organism playing key roles in the development of modern genetics, biochemistry and molecular biology will provide insights into the evolution of snoRNA genes in the fungus kingdom.</p> <p>Results</p> <p>Fifty five box C/D snoRNAs were identified and predicted to guide 71 2'-O-methylated sites including four sites on snRNAs and three sites on tRNAs. Additionally, twenty box H/ACA snoRNAs, which potentially guide 17 pseudouridylations on rRNAs, were also identified. Although not exhaustive, the study provides the first comprehensive list of two major families of snoRNAs from the filamentous fungus <it>N. crassa</it>. The independently transcribed strategy dominates in the expression of box H/ACA snoRNA genes, whereas most of the box C/D snoRNA genes are intron-encoded. This shows that different genomic organizations and expression modes have been adopted by the two major classes of snoRNA genes in <it>N. crassa </it>. Remarkably, five gene clusters represent an outstanding organization of box C/D snoRNA genes, which are well conserved among yeasts and multicellular fungi, implying their functional importance for the fungus cells. Interestingly, alternative splicing events were found in the expression of two polycistronic snoRNA gene hosts that resemble the UHG-like genes in mammals. Phylogenetic analysis further revealed that the extensive separation and recombination of two functional elements of snoRNA genes has occurred during fungus evolution.</p> <p>Conclusion</p> <p>This is the first genome-wide analysis of the filamentous fungus <it>N. crassa </it>snoRNAs that aids in understanding the differences between unicellular fungi and multicellular fungi. As compared with two yeasts, a more complex pattern of methylation guided by box C/D snoRNAs in multicellular fungus than in unicellular yeasts was revealed, indicating the high diversity of post-transcriptional modification guided by snoRNAs in the fungus kingdom.</p

A Herbal Composition of Semen Hoveniae, Radix Puerariae, and Fructus Schisandrae Shows Potent Protective Effects on Acute Alcoholic Intoxication in Rodent Models

This study is designed to evaluate the effects of a herbal composition of Semen Hoveniae, Radix Puerariae and Fructus Schisandrae (SRF) against acute alcoholic intoxication. The animals were treated with SRF extract (SRFE) for 14 days, and ethanol was conducted subsequent to the final treatment. The effects of SRFE on righting reflex, inebriety rates, kinetic parameters of blood ethanol and acetaldehyde were determined. In addition; levels of alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH), the activities of cytochrome P450 2E1 (CYP2E1), selected antioxidative enzymes, and the contents of malonaldehyde (MDA) were measured. SRFE-pretreated rodents exhibited lower rates of intoxication, longer times to loss of righting reflex, and shortened times to recovery of righting reflex than in controls. The peak concentrations and area under the time-concentration curves were lower in the pretreated animals than in controls, which corresponded to higher levels of ADH and ALDH in both gastrointestines and livers of the SRFE-treated animals. The activities of CYP2E1 were lower in SRFE-pretreated animals, which also exhibited higher activities of some antioxidant enzymes and lower hepatic MDA levels. These findings suggest that the anti-inebriation effects of SRFE may involve inhibition of ethanol absorption, promotion of ethanol metabolism, and enhancing hepatic anti-oxidative functions

FGF21 ameliorates the neurocontrol of blood pressure in the high fructose-drinking rats

Fibroblast growth factor-21 (FGF21) is closely related to various metabolic and cardiovascular disorders. However, the direct targets and mechanisms linking FGF21 to blood pressure control and hypertension are still elusive. Here we demonstrated a novel regulatory function of FGF21 in the baroreflex afferent pathway (the nucleus tractus solitarii, NTS; nodose ganglion, NG). As the critical co-receptor of FGF21, β-klotho (klb) significantly expressed on the NTS and NG. Furthermore, we evaluated the beneficial effects of chronic intraperitoneal infusion of recombinant human FGF21 (rhFGF21) on the dysregulated systolic blood pressure, cardiac parameters, baroreflex sensitivity (BRS) and hyperinsulinemia in the high fructose-drinking (HFD) rats. The BRS up-regulation is associated with Akt-eNOS-NO signaling activation in the NTS and NG induced by acute intravenous rhFGF21 administration in HFD and control rats. Moreover, the expressions of FGF21 receptors were aberrantly down-regulated in HFD rats. In addition, the up-regulated peroxisome proliferator-activated receptor-γ and -α (PPAR-γ/-α) in the NTS and NG in HFD rats were markedly reversed by chronic rhFGF21 infusion. Our study extends the work of the FGF21 actions on the neurocontrol of blood pressure regulations through baroreflex afferent pathway in HFD rats