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@#Aortic stenosis (AS) is the most common primary valve lesion requiring surgery or transcatheter intervention in modern era. Its prevalence is rising rapidly as a consequence of the aging population. Transcatheter aortic valve replacement (TAVR) as a therapy option for older high-risk symptomatic severe AS patients has emerged and is currently extending its indications towards surgery intermediate- and low-risk subjects. Considering the common characteristics of frailty and high comorbidity among AS patients, cardiac rehabilitation (CR) has been proven to improve not only survival but also quality of life in previous reports. CR as a classⅠ recommendation in guidelines for the prevention and treatment of cardiovascular disease has been widely used in clinical practice. The purpose of this article is to sort out the current CR programs for TAVR patients in global medical management, and explore the CR optimization program fit for China medical model in post COVID-19 pandemic era.
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Although the functions of metabolic enzymes and nuclear receptors in controlling physiological homeostasis have been established, their crosstalk in modulating metabolic disease has not been explored. Genetic ablation of the xenobiotic-metabolizing cytochrome P450 enzyme CYP2E1 in mice markedly induced adipose browning and increased energy expenditure to improve obesity. CYP2E1 deficiency activated the expression of hepatic peroxisome proliferator-activated receptor alpha (PPARα) target genes, including fibroblast growth factor (FGF) 21, that upon release from the liver, enhanced adipose browning and energy expenditure to decrease obesity. Nineteen metabolites were increased in Cyp2e1-null mice as revealed by global untargeted metabolomics, among which four compounds, lysophosphatidylcholine and three polyunsaturated fatty acids were found to be directly metabolized by CYP2E1 and to serve as PPARα agonists, thus explaining how CYP2E1 deficiency causes hepatic PPARα activation through increasing cellular levels of endogenous PPARα agonists. Translationally, a CYP2E1 inhibitor was found to activate the PPARα-FGF21-beige adipose axis and decrease obesity in wild-type mice, but not in liver-specific Ppara-null mice. The present results establish a metabolic crosstalk between PPARα and CYP2E1 that supports the potential for a novel anti-obesity strategy of activating adipose tissue browning by targeting the CYP2E1 to modulate endogenous metabolites beyond its canonical role in xenobiotic-metabolism.
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Adult olfactory neurogenesis plays critical roles in maintaining olfactory functions. Newly-generated neurons in the subventricular zone migrate to the olfactory bulb (OB) and determine olfactory discrimination, but the mechanisms underlying the regulation of olfactory neurogenesis remain unclear. Our previous study indicated the potential of APPL2 (adaptor protein, phosphotyrosine interacting with PH domain and leucine zipper 2) as a modulating factor for neurogenesis in the adult olfactory system. In the present study, we report how APPL2 affects neurogenesis in the OB and thereby mediates olfactory discrimination by using both in vitro neural stem cells (NSCs) and an in vivo animal model-APPL2 transgenic (Tg) mice. In the in vitro study, we found that APPL2 overexpression resulted in NSCs switching from neuronal differentiation to gliogenesis while APPL2 knockdown promoted neurogenesis. In the in vivo study, APPL2 Tg mice had a higher population of glial cells and dampened neuronal production in the olfactory system, including the corpus callosum, OB, and rostral migratory stream. Adult APPL2 Tg mice displayed impaired performance in olfactory discrimination tests compared with wild-type mice. Furthermore, we found that an interaction of APPL2 with Notch1 contributed to the roles of APPL2 in modulating the neurogenic lineage-switching and olfactory behaviors. In conclusion, APPL2 controls olfactory discrimination by switching the fate choice of NSCs via interaction with Notch1 signaling.
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Adult olfactory neurogenesis plays critical roles in maintaining olfactory functions. Newly-generated neurons in the subventricular zone migrate to the olfactory bulb (OB) and determine olfactory discrimination, but the mechanisms underlying the regulation of olfactory neurogenesis remain unclear. Our previous study indicated the potential of APPL2 (adaptor protein, phosphotyrosine interacting with PH domain and leucine zipper 2) as a modulating factor for neurogenesis in the adult olfactory system. In the present study, we report how APPL2 affects neurogenesis in the OB and thereby mediates olfactory discrimination by using both in vitro neural stem cells (NSCs) and an in vivo animal model-APPL2 transgenic (Tg) mice. In the in vitro study, we found that APPL2 overexpression resulted in NSCs switching from neuronal differentiation to gliogenesis while APPL2 knockdown promoted neurogenesis. In the in vivo study, APPL2 Tg mice had a higher population of glial cells and dampened neuronal production in the olfactory system, including the corpus callosum, OB, and rostral migratory stream. Adult APPL2 Tg mice displayed impaired performance in olfactory discrimination tests compared with wild-type mice. Furthermore, we found that an interaction of APPL2 with Notch1 contributed to the roles of APPL2 in modulating the neurogenic lineage-switching and olfactory behaviors. In conclusion, APPL2 controls olfactory discrimination by switching the fate choice of NSCs via interaction with Notch1 signaling.
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Few medications are available for meeting the increasing disease burden of nonalcoholic fatty liver disease (NAFLD) and its progressive stage, nonalcoholic steatohepatitis (NASH). Traditional herbal medicines (THM) have been used for centuries to treat indigenous people with various symptoms but without clarified modern-defined disease types and mechanisms. In modern times, NAFLD was defined as a common chronic disease leading to more studies to understand NAFLD/NASH pathology and progression. THM have garnered increased attention for providing therapeutic candidates for treating NAFLD. In this review, a new model called "multiple organs-multiple hits" is proposed to explain mechanisms of NASH progression. Against this proposed model, the effects and mechanisms of the frequently-studied THM-yielded single anti-NAFLD drug candidates and multiple herb medicines are reviewed, among which silymarin and berberine are already under U.S. FDA-sanctioned phase 4 clinical studies. Furthermore, experimental designs for anti-NAFLD drug discovery from THM in treating NAFLD are discussed. The opportunities and challenges of reverse pharmacology and reverse pharmacokinetic concepts-guided strategies for THM modernization and its global recognition to treat NAFLD are highlighted. Increasing mechanistic evidence is being generated to support the beneficial role of THM in treating NAFLD and anti-NAFLD drug discovery.
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Objective@#To evaluate clinical efficacy and safety of microneedle-mediated intradermal injection with hyaluronic acid for the treatment of sensitive skin.@*Methods@#A total of 53 female patients aged 21-54 years and diagnosed with sensitive skin were enrolled from Department of Cosmetic Dermatology, Dermatology Hospital of Southern Medical University from January to June in 2018, and were divided into 3 groups by using a random number generator and a residue-based method: high-pressure jet injection group (n = 23) receiving high-pressure jet injection with hyaluronic acid on the right side of the face (treatment side) and high-pressure jet injection with 0.9% sodium chloride solution on the left side of the face (control side) once every 2 weeks, microneedle injection group (n = 15) receiving microneedle-mediated injection with hyaluronic acid on the right side of the face (treatment side) and microneedle-mediated injection with 0.9% sodium chloride solution on the left side of the face (control side) once every 4 weeks, combination group (n = 15) receiving microneedle-mediated injection with hyaluronic acid on the right side of the face (treatment side) and high-pressure jet injection with hyaluronic acid on the left side of the face (control side) once every 4 weeks. All the patients in the above 3 groups received 4 consecutive sessions of treatment. Before the initial treatment and 2 weeks after the final treatment, erythema and skin pore scores were determined on the right and left sides of the face by using VISIA facial imaging system, lactic acid stinging test was performed, and skin sensitivity including severity of itching, dryness, erythema and scaling was evaluated. Two weeks after the final treatment, the overall improvement was evaluated with the Global Aesthetic Improvement Scale (GAIS) by clinicians and patients. Adverse reactions were recorded during and after treatment. Statistical analysis was carried out by using paired t test, Wilcoxon sign rank sum test and chi-square test.@*Results@#Two weeks after the final treatment, the improvement of skin pore score in the treatment side was superior to that in the control side in the high-pressure jet injection group (t = 2.19, P = 0.03) , while no significant difference in the improvement of erythema score was observed between the treatment side and control side (t = 1.10, P = 0.27) ; in the microneedle injection group, the improvement of erythema and skin pore scores was greater in the treatment side than in the control side (t = 2.47, 3.02, both P = 0.01) ; in the combination group, the VISIA erythema score in the treatment and control sides was 0.59 ± 0.25 and 0.85 ± 0.31 respectively, the improvement of erythema score in the treatment side was superior to that in the control side (t = 5.02, P < 0.01) , while there was no significant difference in the improvement of skin pore score between the treatment side and control side (P > 0.05) . Two weeks after the final treatment, the severity of itching, dryness and scaling was significantly improved in both the treatment and control sides in the 3 groups compared with those before the initial treatment (P < 0.05) , while the severity of erythema was significantly improved only in the treatment side in the microneedle injection group and combination group when compared with that before the initial treatment (Z = -2.236, -2.887, respectively, both P < 0.05) . Moreover, both the microneedle injection group and combination group showed significantly decreased severity of erythema in the treatment side compared with that in the control side two weeks after the final treatment (Z = -2.646, -2.887, respectively, both P < 0.05) . Two weeks after the final treatment, the positive rate of the lactic acid stinging test significantly decreased in the treatment side compared with that before the initial treatment in the microneedle injection group (χ2 = 4.821, P = 0.028) , but showed no significant changes in the other groups (all P > 0.05) . No severe adverse reactions were observed during or after the treatment.@*Conclusion@#Microneedle intradermal injection with hyaluronic acid can effectively and safely improve erythema, skin pore and sensitive symptoms in patients with sensitive skin.
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Objective To evaluate clinical efficacy and safety of microneedle-mediated intradermal injection with hyaluronic acid for the treatment of sensitive skin.Methods A total of 53 female patients aged 21-54 years and diagnosed with sensitive skin were enrolled from Department of Cosmetic Dermatology,Dermatology Hospital of Southern Medical University from January to June in 2018,and were divided into 3 groups by using a random number generator and a residue-based method:high-pressure jet injection group (n =23) receiving high-pressure jet injection with hyaluronic acid on the right side of the face (treatment side) and high-pressure jet injection with 0.9％ sodium chloride solution on the left side of the face (control side) once every 2 weeks,microneedle injection group (n =15) receiving microneedle-mediated injection with hyaluronic acid on the right side of the face (treatment side)and microneedle-mediated injection with 0.9％ sodium chloride solution on the left side of the face (control side) once every 4 weeks,combination group (n =15) receiving microneedle-mediated injection with hyaluronic acid on the right side of the face (treatment side) and high-pressure jet injection with hyaluronic acid on the left side of the face (control side) once every 4 weeks.All the patients in the above 3 groups received 4 consecutive sessions of treatment.Before the initial treatment and 2 weeks after the final treatment,erythema and skin pore scores were determined on the right and left sides of the face by using VISIA facial imaging system,lactic acid stinging test was performed,and skin sensitivity including severity of itching,dryness,erythema and scaling was evaluated.Two weeks after the final treatment,the overall improvement was evaluated with the Global Aesthetic Improvement Scale (GAIS)by clinicians and patients.Adverse reactions were recorded during and after treatment.Statistical analysis was carried out by using paired t test,Wilcoxon sign rank sum test and chi-square test.Results Two weeks after the final treatment,the improvement of skin pore score in the treatment side was superior to that in the control side in the high-pressure jet injection group (t =2.19,P =0.03),while no significant difference in the improvement of erythema score was observed between the treatment side and control side (t =1.10,P =0.27);in the microneedle injection group,the improvement of erythema and skin pore scores was greater in the treatment side than in the control side (t =2.47,3.02,both P =0.01);in the combination group,the VISIA erythema score in the treatment and control sides was 0.59 ± 0.25 and 0.85 ± 0.31 respectively,the improvement of erythema score in the treatment side was superior to that in the control side (t =5.02,P ＜ 0.01),while there was no significant difference in the improvement of skin pore score between the treatment side and control side (P ＞ 0.05).Two weeks after the final treatment,the severity of itching,dryness and scaling was significantly improved in both the treatment and control sides in the 3 groups compared with those before the initial treatment (P ＜ 0.05),while the severity of erythema was significantly improved only in the treatment side in the microneedle injection group and combination group when compared with that before the initial treatment (Z =-2.236,-2.887,respectively,both P ＜ 0.05).Moreover,both the microneedle injection group and combination group showed significantly decreased severity of erythema in the treatment side compared with that in the control side two weeks after the final treatment (Z =-2.646,-2.887,respectively,both P ＜ 0.05).Two weeks after the final treatment,the positive rate of the lactic acid stinging test significantly decreased in the treatment side compared with that before the initial treatment in the microneedle injection group (x2 =4.821,P =0.028),but showed no significant changes in the other groups (all P ＞ 0.05).No severe adverse reactions were observed during or after the treatment.Conclusion Microneedle intradermal injection with hyaluronic acid can effectively and safely improve erythema,skin pore and sensitive symptoms in patients with sensitive skin.
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Objective To establish an efficient method of genotyping for Leprdb/ +mouse offsprings by TaqMan probe quantitative fluorescence PCR. Methods Genome DNA was extracted from tails of 228 Leprdb/ +mouse offsprings. PCR primers and TaqMan probes were designed according to the mutation sites of Lepr gene(rs1801133). Real time PCR assay was applied and SNP loci were typed with SDS software. The genotyping of 2-month old Leprdb/dbmice was validated by the phenotype and Hardy-Weinberg equilibrium test was performed. Results 228 samples were detected by the established TaqMan fluorescence quantitative PCR assay. 64 mice were of GG genotype, with a genotype frequency of 0.1929. 123 mice were of GT genotype, with a genotype frequency of 0.5395. 41 mice were of TT genotype, with a genotype frequency of 0.2807. Compared with the phenotype typing,the sensitivity of the TaqMan fluorescence quantitative PCR was 97.56% and the specificity was 99.47%. Conclusions TaqMan probe quantitative fluorescence PCR assay is a simple and efficient method,and can be used to detect the genotype of Leprdb/ +mouse offsprings.
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Objective To study the expression of lipoic acid synthase(LIAS)in the liver and kidney of Leprdb/db mice with deficient leptin receptor. Methods Eight 10-week old male Leprdb/ +mice and Leprdb/dbmice were included in this study. The body weight of rats in the two groups was measured. Fasting blood glucose(FPG)was measured with blood glucose test strips for all mice after fasting for 8 hours. Blood samples were obtained from the abdominal aorta and the animals were sacrificed. The liver and kidney were weighed. The right lobe of liver and the left kidney samples were fixed in 4% paraformaldehyde for pathological examination. Serum samples were separated and the sereum contents of CHO, TG,HDL and LDL were detected. The mitochondria of liver and kidney tissues were extracted with a mitochondrial isolation kit, and the protein was extracted. The expression of LIAS protein was detected by western blot. Results Histopathological observation showed that the liver and kidney tissues of Leprdb/ +mice have intact and clear structure. But the liver tissue of Leprdb/dbmice showed fatty degeneration, the kidney tissue showed glomerular hypertrophy, basement membrane thickening, mesangial area widened, including mesangial cells and mesangial matrix increased. The GLU,CHO,TG,LDL and AST of Leprdb/dbmice were significantly increased compared with those of Leprdb/ +mice(P<0.05). Compared with Leprdb/ +mice,the LIAS protein expression was significantly increased in the liver and kidney mitochondria of Leprdb/dbmice(P<0.05). Conclusions There is impaired glucose and lipid metabolism in the Leprdb/dbmice which has defect leptin receptor,and the expression of LIAS protein in liver and kidney of the Leprdb/dbmice is higher than that of Leprdb/ +mice.
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Background:CBX3 is a member of heterochromatin protein family. Recent studies indicated that CBX3 was closely related to lung cancer,osteosarcoma,gastric cancer. Aims:To investigate the expression and clinical significance of CBX3 in colorectal cancer,and explore the potential mechanism. Methods:Thirty colorectal cancer patients from June 2011 to June 2012 at Shanghai Renji Hospital were enrolled. Real-time quantitative PCR and immunohistochemistry were used to determine mRNA and protein expressions of CBX3 in colorectal cancer tissues and corresponding paracancerous tissues, respectively. Human colorectal cancer cell line RKO was transfected with overexpressed plasmid or siRNA of CBX3. Cell proliferation was measured by CCK-8 assay,Western blotting was implemented to determine the protein expressions of CBX3 and p53. Results:The mRNA and protein expressions of CBX3 were significantly increased in colorectal cancer tissues than in corresponding paracancerous tissues. Increased protein expression of CBX3 was closely correlated with tumor size (P ＝ 0. 025 ),lymph node metastasis (P ＝ 0. 013 )and TNM staging (P ＝ 0. 020 ). After intervention with overexpressed plasmid of CBX3,the mRNA and protein expressions of CBX3 were efficiently upregulated in RKO cells, cell proliferation and protein expression of p53 were significantly increased. Meanwhile,the mRNA and protein expressions of CBX3 were efficiently downregulated in RKO cells after knockdown of CBX3,resulting in significantly decreased cell proliferation and protein expression of p53. Conclusions:CBX3 may promote the proliferation of colorectal cancer cells via influencing the expression of p53,thus promoting the progression of colorectal cancer. This indicates that CBX3 has the potential to be a new target for diagnosis and therapy of colorectal cancer.
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Objective To explore the nursing soft skills constitute elements of higher vocational nursing students and give some suggestions for their education. Methods A qualitative study was used. In-depth individual interviews were conducted with 15 participants including higher vocational nursing educators, nursing managers and clinical nursing teachers. The results were finally coded, described, classified and analyzed. Results The nursing soft skills of higher vocational nursing students are composed of three main dimensions comprising personal attributes, interpersonal skills and conceptual/thinking skills, among which personal attributes include personality and self-management; interpersonal skills include interpersonal communication and teamwork skills; conceptual/thinking skills include problem-solving and critical-thinking skills. Conclusions Personal attributes are the decisive elements for higher vocational nursing students' competencies. Interpersonal skills are the core competency for nursing works. Conceptual/thinking skills ensure higher vocational nursing students to acquire sustained development. A systematic nursing soft skills training model should be constructed.
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Objective@#To investigate the role of enolase 1 (ENO1) in hepatocellular carcinoma (HCC) and possible mechanism.@*Methods@#Real-time PCR and Western blot were used to measure the expression of ENO1 in HCC tissue, adjacent tissue, hepatoma cells, and normal hepatocytes. The siRNA interference technique was used for ENO1 knockout in HepG2 cells, and then CCK-8, colony formation assay, and transwell assay were used to measure the proliferation, migration, and invasion abilities of HepG2 cells. Real-time PCR and Western blot were used to measure the expression of proteins and genes involved in the activation of the Notch signaling pathway. The two-independent-samples t test and a one-way analysis of variance were used for comparison.@*Results@#HCC tissue and HepG2 cells had significantly higher expression of ENO1 than adjacent tissue and normal hepatocytes (P < 0.05). There were significant reductions in the proliferation, migration, and invasion abilities of HepG2 cells after siRNA interference (P < 0.05). There were also significant reductions in the expression of N1ICD, snail, slug, HEY1, HES1, and HES5 (P < 0.05).@*Conclusion@#ENO1 may promote the development of HCC, possibly by participating in the regulation of the Notch signaling pathway.
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Objective To observe the effect of electroacupuncture at the beginning and ending points of bicipital muscle on the superficial electromyography (sEMG) of the spastic limb in hemiplegia.Method Forty patients with spastic hemiplegia after cerebral stroke were divided by the random number table into a group of electroacupuncture at the beginning and ending points (group A) and a group of electroacupuncture at antagonistic muscles (group B). The former selected Ashi points at the beginning and ending points of bicipital muscle, while the latter selected points at the antagonistic muscles [Tianjing (TE10), Qinglingyuan (TE11), etc.], to receive perpendicular puncturing. The needles were retained for 30 min, and the sEMG of bicipital muscles in resting state was detected after the removal of the needles. The spastic bicipital muscle was examined by sEMG prior to the acupuncture treatment, and respectively after 2-week and 4-week acupuncture treatment, and the detected parameters included root mean square (RMS) and integrated electromyography (IEMG).ResultThe EMG and IEMG declined gradually in the two groups after the acupuncture treatment; the intra-group comparisons of the RMS and IEMG values at three time points, e.g. prior to acupuncture treatment, after 2-week acupuncture treatment and after 4-weekacupuncture treatment, showed that the values changed significantly compared to those at the previous time point (P0.05). The RMS and IEMG values presented same changing tendencies after 4-week acupuncture treatment in the two groups.ConclusionAcupuncture at the beginning and ending points and at the points on antagonistic muscles both can decrease the resting-state muscle tension in hemiplegia patients; sEMG is of certain significance in evaluating the treatment of hemiplegia.
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Urid acid is one of the terminal metabolites of human body.More and more attention was paid to its metabolic mechanisms in intestinal tract;however, few studies were seen so far.This study aims to illuminate the metabolic mechanism of uric acid in intestinal tract by two ways:one is the transporters associated with intestinal epithelium, including ABCG2 and SLC2A9, the other is decomposition of uric acid by intestinal flora.We hope this review can provide new insights to decrease blood uric acid and treat urate-related diseases, and also provide a new way to alleviate drug-induced kidney damage.
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Background:Vitamin D receptor( VDR)is a member of the steroid hormone receptor superfamily,which plays roles in various biological processes including cell proliferation,differentiation,apoptosis and immune responses,and is low expressed in many malignant tumors. Aims:To evaluate the expression and regulation mechanism of VDR in colorectal cancer. Methods:A total of 30 patients with colorectal cancer admitted from February 2010 to December 2012 at Ren Ji Hospital,School of Medicine,Shanghai Jiao Tong University were enrolled. Expression of VDR in cancerous tissue and para-cancer noncancerous tissue was determined by immunohistochemistry. Clinical data of 224 patients with colorectal cancer were collected from Gene Expression Omnibus( GEO)for analyzing the correlation between VDR expression in cancerous tissue and clinicopathological characteristics as well as survival time. Expression of VDR in human colon cancer cell lines HCT116 and SW620 transfected with enhancer of zeste homolog 2( EZH2 )-siRNA or treated with 5-azacytidine (5-AZA)was determined by real-time PCR,and methylation level of VDR promoter was determined by methylation-specific PCR( MSP). Results:Positivity rate of VDR was significantly lower in colorectal cancer tissue than that in para-cancer noncancerous tissue( 26. 7% vs. 70. 0%,P < 0. 001 ). Expression of VDR was negatively correlated with histological staging,distant metastasis,vascular metastasis and lymph node metastasis of colorectal cancer(P<0. 05). Survival time was significantly longer in patients with high expression of VDR than patients with low expression of VDR (P=0. 032). Compared with cells transfected with control-siRNA,expression of EZH2 mRNA and methylation level of VDR promoter in HCT116 and SW620 cells transfected with EZH2-siRNA were significantly decreased(P<0. 05),and expression of VDR mRNA was significantly increased(P<0. 05). Compared with negative control group,methylation level of VDR promoter in HCT116 and SW620 cells treated with 5-AZA was significantly decreased(P<0. 05),and expression of VDR mRNA was significantly increased(P<0. 05). Conclusions:Expression of VDR in colorectal cancer is down-regulated and positively correlated with a favourable prognosis. Transcriptional repression of VDR in colorectal cancer is co-regulated by histone methylation and DNA methylation.
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This study seeks to explore the early signs of cognitive impairment in patients with obstructive sleep apnea hypopnea syndrome (OSAHS). According to polysomnography, twenty patients diagnosed with OSAHS and twenty normal controls underwent event-related potential (ERP) examination including mismatch negativity (MMN) and P300. Compared with normal controls, OSAHS patients showed significantly prolonged latency of MMN and P300 at Cz. After controlling age and body mass index (BMI), MMN latency positively correlated with apnea hypopnea index (AHI), oxygen reduction index, stage N1 sleep and arousal index, while MMN latency negatively correlated with stage N3 sleep and mean blood oxygen saturation; and P300 latency positively related to AHI and oxygen reduction index; no relationships were found among MMN latency, MMN amplitude, P300 latency and P300 amplitude. These results suggest that the brain function of automatic processing and controlled processing aere impaired in OSAHS patients, and these dysfunction are correlated with nocturnal repeatedly hypoxemia and sleep structure disturbance.
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Humans , Case-Control Studies , Cognition Disorders , Event-Related Potentials, P300 , Hypoxia , Oximetry , Polysomnography , Sleep Apnea, Obstructive , Sleep StagesABSTRACT
A new stent with triangular wire cross-section was proposed. The new stents were compared with traditional circular wire cross-section stent in the same porosity in order to investigate its effectiveness in treating intracranial aneurysms. Three models were established separately, including the aneurysm model with circle cross section stent, the aneurysm model with triangular cross section stent and the aneurysm model with non-stent. Then the same boundary conditions were set to contrast the resistance to flow, velocity, pressure, wall shear stress and total mesh displacement. The resistance to flow of triangular cross section stent was lower than circle cross section stent and the velocity, pressure, total mesh displacement of aneurysm model with triangular cross section stent were all higher than those of the model with circle cross section stent. Moreover, the peak value and valley value of wall shear stress in aneurysm model with triangular cross section stent were higher than those of the other. Triangular cross section stent might play a negative role to aneurysm rupturing. Thus, the therapeutic effect of stent with triangle cross section was not better than the stent with circle cross section. In the clinical application, doctors should consider the various factors, and choose the most suitable one.
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Humans , Aneurysm , Therapeutics , Computer Simulation , Hemorheology , Physiology , Intracranial Aneurysm , Therapeutics , Prosthesis Design , StentsABSTRACT
A chimeric protein called Wallerian degeneration slow (Wld(S)) was first discovered in a spontaneous mutant strain of mice that exhibited delayed Wallerian degeneration. This provides a useful tool in elucidating the mechanisms of axon degeneration. Over-expression of Wld(S) attenuates the axon degeneration that is associated with several neurodegenerative disease models, suggesting a new logic for developing a potential protective strategy. At molecular level, although Wld(S) is a fusion protein, the nicotinamide mononucleotide adenylyl transferase 1 (Nmnat1) is required and sufficient for the protective effects of Wld(S), indicating a critical role of NAD biosynthesis and perhaps energy metabolism in axon degeneration. These findings challenge the proposed model in which axon degeneration is operated by an active programmed process and thus may have important implication in understanding the mechanisms of neurodegeneration. In this review, we will summarize these recent findings and discuss their relevance to the mechanisms of axon degeneration.
Subject(s)
Animals , Humans , Mice , Axons , Physiology , Mice, Mutant Strains , Models, Neurological , Mutant Proteins , Genetics , Physiology , Mutation , NAD , Nerve Degeneration , Genetics , Nerve Tissue Proteins , Genetics , Physiology , Nicotinamide-Nucleotide Adenylyltransferase , Genetics , PhysiologyABSTRACT
Objective To make a preliminary evaluation of the degradation of AZ31 bioabsorbable magnesium alloy stent implanted in the abdominal aorta of experimental rabbits.Methods Twelve AZ31 biodegradable magnesium alloy stents were separately deployed in the infrarenal abdominal aortas of twelve New Zealand white rabbits.Every three experimental rabbits were sacrificed each time at one,two,three and four months after the procedure of stenting.The stenting segment of the aortas were harvested,radiographod and sent for pathologic examination to observe the degradable performance of the stent.Results All animals survived form the operation in the scheduled follow-up period.Radiographically and pathologically,the stents were fully expanded with perfect shape one month after the procedure,and part of the stent struts began to be degraded and fractured in two months,resulting in the loss of its supporting function.Three months after the implantation most stents were corroded.and in four months all the stents become completely destroyed.The estimating time for producing complete degradation of AZ31 magnesium alloy stents in rabbit's aorta was 104.5 days.Conclusion AZ31 bioabsorbable magnesium alloy stents implanted in rabbit abdominal aorta will lose their radial force in two months.How to prolong the functioning time of the implanted stents is the next research target.