TMSN-AA纳米复合物促进人胚胎干细胞向心肌细胞分化的潜在机制研究

目的研究优化后的TMSN-AA纳米复合物促进人胚胎干细胞(h ESCs)心肌分化的可能性,并探讨其诱导心肌分化的潜在机制。方法采用优化抗坏血酸(AA)负载的荧光TRITC介孔二氧化硅纳米粒子(TMSN-AA)作为诱导剂,诱导h ESCs细胞心肌分化。通过荧光定位检测该诱导剂进入细胞情况,流式细胞仪检测其进入细胞后对细胞存活与凋亡的影响,Western blot检测TMSN-AA诱导后,心肌标记基因cTn I、FLK-1以及干性基因OCT4和SOX2的表达以及相关信号通路ERK1/2的激活情况。结果荧光定位发现TMSN-AA可以靶向进入h ESCs细胞,流式细胞仪分析结果显示,二氧化硅和荧光染料四甲基罗丹明修饰介孔二氧化硅不会影响h ESCs的存活和凋亡;且TMSN-AA诱导后,干性基因OCT4和SOX2均下调,且上调心肌标记基因c Tn I和FLK-1的表达。Western blot检测结果显示,TMSN-AA的处理可以激活ERK1/2信号通路,同时证实,该过程Akt信号通路并未参与其中。结论优化后的TMSN-AA纳米载体可以成功进入h ESCs细胞,并靶向诱导其心肌分化,而该诱导过程,至少在一定程度上是通过激活ERK1/2,而不是Akt信号通路实现的。

Different histological subtypes of parotid gland tumors: CT findings and diagnostic strategy

AIM:To present computed tomography(CT) findings of different histological subtypes of parotid gland masses in detail and to establish diagnostic strategy.METHODS:From January 2009 to November 2011,56 patients were collected through the histopathology and Picture Archiving and Communication Systems records,which revealed 5 basal cell adenoma(BCA),16 pleomorphic adenoma(PA),25 Warthin's tumor(War-T),3 Kimura's disease(KD) and 7 parotid carcinoma(PCa) cases.All the CT images were retrospectively analyzed by two radiologists in consensus,based on their description of morphology(location,number,size,margin and fibrous capsule) and enhancement patterns of masses.In addition,the diagnostic efficiency of diagnostic strategy is tested.RESULTS:War-T and BCA patients' mean age was 59.9 ± 12.6 years and 58.4 ± 18.2 years;the significant difference was seen in War-T vs PA and BCA vs PA.About 40% of War-Ts presented with bilateral multifocal lesions,a higher ratio than others.Seventy two percent of War-Ts were limited to the superficial lobe,followed by BCA 60% and PA 40%.Vessel facing sign and enlarged lymph nodes were both frequent in War-T,which respectively accounts for 84% and 76% of cases.Rapid contrast enhancement and decreases were unique for War-T.BCA and PA showed obvious delayed enhancement.The diagnostic strategy of parotid gland tumor had a good diagnostic efficiency,with high accuracy,sensitivity and specificity.CONCLUSION:Determination of the histological subtypes of parotid gland masses might be possible based on CT findings and clinical data.A diagnostic strategy with high diagnostic efficiency was established.

Uterine intravenous leiomyomatosis with cardiac extension: Imaging characteristics and literature review

Intravenous leiomyomatosis(IVL),showing unusual growth patterns of uterine leiomyoma,is a rare neoplasm characterized by intravascular proliferation of a histologically benign-looking smooth muscle cell tumor mass,but not invading the tissue.To date,less than 300 cases have been reported and fewer than 100 cases with cardiac involvement.Imaging characteristics of IVL are still not clear so it is usually misdiagnosed before surgery.A 36-year-old woman,who had undergone hysterectomy due to hysteromyoma,presented with shortness of breath after activities.Imaging showed IVL with mass involvement of the left ovarian vein,left renal vein,left external and common iliac vein,as well as within the inferior vena cava(IVC),extending into the right atrium.The operation demonstrated that the mass had no stalk and had welldemarcated borders with the wall of the right atrium and IVC.The patient underwent a one-stage combined multidisciplinary thoraco-abdominal operation under general anesthetic.Subsequently,the pathology report confirmed IVL.IVL should be considered in a female patient presenting with an extensive mass in the right side of the heart.Imaging technology,such as echocardiogram,contrast-enhanced computed tomography and magnetic resonance imaging,can provide important information to reveal the mass,the range and path of the lesion,and relates to the surgical plan decision.Consequently,perfect and exact image examination is very necessary pre-operation.

PRSS1_p.Leu81Met mutation results in autoimmune pancreatitis

AIM: To describe protease serine 1 (PRSS1) gene mutations in patients with autoimmune pancreatitis (AIP) and the clinical features of AIP. METHODS: Fourteen patients with AIP, 56 with other chronic pancreatitis, 254 with pancreatic cancer and 120 normal controls were studied. The mutations and polymorphisms of four genes involved with pancreatitis or pancreatic cancer, PRSS1 , SPINK1 , CFTR and MEN1 , were sequenced. The pathogenic mechanism of AIP was investigated by comparing the wild-type expression system with the p.81Leu→Met mutant expression system. RESULTS: Two novel mutations (p.81Leu→Met and p.91Ala→Ala) were found in PRSS1 gene from four patients with AIP. PRSS1_p.81Leu→Met mutation led to a trypsin display reduction (76.2%) combined with phenyl agarose (Ca2+ induced failure). Moreover, the ratio of trypsin/amylase in patients with AIP was higher than in the patients with pancreatic cancer and other pancreatitis. A large number of lymphocytes and plasma cells were found in the bile ducts accompanied by hyperplasia of myofibroblasts. CONCLUSION: Autoimmune pancreatitis may be related to PRSS1 gene mutations.

Cu^2+-catalyzed mechanism in oxygen-pressure acid leaching of artificial sphalerite

The potential autoclave was used to study the catalytic mechanism of Cu^2+during the oxygen pressure leaching process of artificial sphalerite.By studying the potential change of the system at different temperatures and the SEM–EDS difference of the leaching residues,it was found that in the temperature range of 363–423 K,the internal Cu^2+formed a Cu S deposit on the surface of sphalerite,which hindered the leaching reaction,resulting in a zinc leaching rate of only 51.04%.When the temperature exceeds 463 K,the system potential increases steadily.The increase in temperature leads to the dissolution of the CuS,which is beneficial to the circulation catalysis of Cu^2+.At this time,the leaching rate of Zn exceeds 95%.In addition,the leaching kinetics equations at 363–423 and 423–483 K were established.The activation energy of zinc leaching at 363–423 and 423–483 K is 38.66 and 36.25 kJ/mol,respectively,and the leaching process is controlled by surface chemical reactions.

CNKSR2 mutation causes the X-linked epilepsy-aphasia syndrome:A case report and review of literature

The mutation in CNKSR2 leads to a broad spectrum of phenotypic variability and manifests as an X-linked intellectual disability. However, we reported that the male patient in this study not only had intellectual disability but also epileptic seizures. In addition, there were progressive language impairment, attention deficit hype-ractivity disorder and autism. Electroencephalograms showed continuous spike-and-wave during sleep. Genetic testing revealed a de novo mutation of the CNKSR2 gene(c.2185C >T, p.Arg729Ter) in the child that was not detected in the parents. Therefore, the child was diagnosed with X-linked epilepsy aphasia syndrome. Deletion of the CNKSR2 gene has been rarely reported in epilepsy aphasia syndrome, but no de novo mutation has been found in this gene. This report not only adds to the spectrum of epilepsy aphasia syndrome but also helps clinicians in diagnosis and genetic counseling.

Separation of halogens and recovery of heavy metals from secondary copper smelting dust

The separation of halogens and recovery of heavy metals from secondary copper smelting(SCS)dust using a sulfating roasting−water leaching process were investigated.The thermodynamic analysis results confirm the feasibility of the phase transformation to metal sulfates and to gaseous HF and HCl.Under the sulfating roasting conditions of the roasting temperature of 250°C and the sulfuric acid excess coefficient of 1.8,over 74 wt.%of F and 98 wt.%of Cl were volatilized into flue gas.Approximately 98.6 wt.%of Zn and 96.5 wt.%of Cu in the roasting product were dissolved into the leaching solution after the water leaching process,while the leaching efficiencies of Pb and Sn were only 0.12%and 0.22%,respectively.The mechanism studies indicate the pivotal effect of roasting temperature on the sulphation reactions from various metal species to metal sulfates and the salting out reactions from various metal halides to gaseous hydrogen halides.

Palladium-catalyzed alkynylative[5+1]carboannulation of 1,3-diarylprop-2-yn-1-yl acetates with terminal alkynes enabled by C-H functionalization

A new method for the synthesis of 3-ethynyl-1-methylene-1,2-dihydronaphthalenes via copper-pro-moted palladium-catalyzed intermolecular alkynylative[5+1]carboannulation of 1-arylphenyl-prop-2-yn-1-yl acetates involving C–H functionalization is described.Two terminal alkyne molecules serve as an alkynylation reagent and a one-carbon unit to enable alkynylative[5+1]carboannulation with excellent selectivity control,broad substrate scope and good tolerance of functional groups.