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1.
Genetic susceptibility to retinopathy of prematurity (ROP) has been reported. However, no virulence genes are currently known for ROP. This study aimed to assess FZD4, LRP5, TSPAN12, and NDP, which are known virulence genes involved in familial exudative vitreoretinopathy, an ailment that shares some symptoms with ROP. After approval from the parents of diseased infants, blood samples from 29 Han patients with ROP were collected for genomic DNA extraction. Direct sequencing was used to assess the four candidate genes, namely FZD4, LRP5, TSPAN12, and NDP. Finally, genetic mutations were screened. Changes of three nucleotide sequences were found in the four candidate genes; notably, a c.954G>A hybrid mutation in the TSPAN12 gene was predicted to cause protein structure and function alterations. The molecular pathogenesis of ROP is complex, and likely involves the c.954G>A mutation in TSPAN12.  相似文献   

2.
In this paper, the circadian pattern of Clock and genes mediated by the Clock was investigated in peripheral lymphocytes of rats. Circadian rhythms of Clock are found under the regimes of constant darkness (DD) and 12-h light-12-h dark (LD12:12h), with the peak phase at CT7 and ZT21, respectively. Ten differential cDNA fragments were identified to be mediated by the Clock, including three known genes (catalase, myelin proteolipid protein, and histone acetylase), four known expressed sequence tags (ESTs), and three novel ESTs. Experiment of the RNA interference revealed that these ESTs were down-regulated by the Clock gene and three of them were identified as clock-controlled genes. Understanding of clock-mediated genes may lead to a new direction in drug design for control of circadian rhythms.  相似文献   

3.
Three novel scalarane sesterterpenes were isolated from a Korean marine sponge, Psammocinia sp., along with four known derivatives. Their structures were elucidated on the basis of NMR, MS and IR spectroscopic data. The three new compounds are 12-deacetoxy-23-hydroxyscalaradial (1), 12-dehydroxy-23-hydroxyhyrtiolide (2) and 12-O-acetyl-16-deacetoxy-23-acetoxyscalarafuran (3), respectively, and the four known compounds are 12-deacetoxy-23-hydroxyheteronemin (4), 12-deacetoxy-23-acetoxy-19-O-acetylscalarin (5), 12-deacetoxy-23-O-acetoxyheteronemin (6) and 12-deacetoxyscalaradial (7). They exhibited cytotoxicity against intractable human cancer cell lines A498, ACHN, MIA-paca and PANC-1, with an IC50 range of 0.4–48 μM.  相似文献   

4.
Three abietane diterpenoids were isolated from the suspension cultured cells of Torreya nucifera var. radicans along with four known abietane diterpenoids. Based on spectroscopic evidence, the structures of the three were elucidated as (3S,5R,10S)-7-oxo-12-methoxyabieta-8,11,13-triene-3,11-diol, (3S,5R,10S)-7-oxo-12-methoxyabieta-8,11,13-triene-3,11,14-triol and (5R,10S)-3-oxo-7R,12-dimethoxyabieta-8,11,13-trien-11-ol, respectively.  相似文献   

5.
Calea trichomata gave in addition to four known 1β-hydroxy-8β-tigloyloxy-11(13)-eudesmen-6α, 12-olide derivatives a new heliangolide, 3-deoxy  相似文献   

6.
Two new pentahydroxylated steroids, (3β,12β,16β,23E)-cholesta-5,23-diene-3,12,16,20,25-pentaol (1) and (3β,12β,16β)-cholesta-5,25(26)-diene-3,12,16,20,24-pentaol (2), were isolated from the EtOH extract of the South China Sea gorgonian Subergorgia suberosa. In addition, four known steroids were detected. The structures of these compounds were established by spectroscopic methods and comparison of their data with those of the related known compounds. In addition, the cyctotoxicities of the compounds were evaluated against selected cancer cell lines.  相似文献   

7.
Yoon SH  Robyt JF 《Carbohydrate research》2003,338(19):1969-1980
Acarbose analogues, 4IV-maltohexaosyl acarbose (G6-Aca) and 4IV-maltododecaosyl acarbose (G12-Aca), were prepared by the reaction of cyclomaltodextrin glucanyltransferase with cyclomaltohexaose and acarbose. The inhibition kinetics of acarbose and the two acarbose analogues were studied for four different alpha-amylases: Aspergillus oryzae, Bacillus amyloliquefaciens, human salivary, and porcine pancreatic alpha-amylases. The three inhibitors showed mixed, noncompetitive inhibition, for all four alpha-amylases. The acarbose inhibition constants, Ki, for the four alpha-amylases were 270, 13, 1.27, and 0.80 microM, respectively; the Ki values for G6-Aca were 33, 37, 14, and 7 nM, respectively; and the G12-Aca Ki constants were 59, 81, 18, and 11 nM, respectively. The G6-Aca and G12-Aca analogues are the most potent alpha-amylase inhibitors observed, with Ki values one to three orders of magnitude more potent than acarbose, which itself was one to three orders of magnitude more potent than other known alpha-amylase inhibitors.  相似文献   

8.
A 2 2/3-year-old girl with 12p trisomy resulting from a maternal translocation is presented. Her clinical symptoms are strikingly similar to the other four cases known in the literature. A characteristic combination of symptoms for a 12p trisomy syndrome is delineated.  相似文献   

9.
Z Kiss  Y A Luo 《FEBS letters》1986,198(2):203-207
Phosphorylation of liver plasma proteins by protein kinase C was studied by using the two best known activators of the enzyme, 12-O-tetradecanoylphorbol-13-acetate (TPA) and 1,2-diolein. While the effects of TPA and diolein were almost identical on two proteins and similar in magnitude on four proteins, the phosphorylation of an additional four proteins was increased only by TPA. We conclude that in respect to phosphorylation of membrane proteins, TPA and diglycerides are not fully equivalent activators of kinase C.  相似文献   

10.
采用抑制差减杂交技术(Suppression subtractive hybridization,SSH)对禽致病性大肠杆菌E037株(血清型O78)与非致病菌株K-12MG1655以及同一O2血清型高致病菌株E058与低致病菌株E526进行基因组差异片段克隆与分析。从E037株中共检出17个特异性差异片段,E058株中共检出32个特异性差异片段。经同源分析,这些序列可分为4类:质粒相关序列、噬菌体相关序列、已知功能序列、未知功能序列。这些差异片段包含许多重要的大肠杆菌毒力相关基因,如大肠杆菌素、气杆菌素受体、铁基因簇等。49个片段中,14个片段与其它微生物基因组同源性较高。结果表明,大肠杆菌高致病株与低致病菌株或非致病菌株基因组间存在较多差异基因,其中包括毒力、毒力相关基因、代谢以及噬菌体等基因成分。  相似文献   

11.
Examination of the aerial parts of Achillea clavennae afforded eight guaianolides (1-8), three bisabolenes (9-11), four flavonols (12-15), sesamin (lignan) and isofraxidin (coumarin). The structures of the new compounds (2, 4, 5, 7 and 10) were determined by spectroscopic methods. The antiproliferative action of 2, 8, 9 and 12 were tested to HeLa, K562 and Fem-X human cancer cell lines. Guaianolides 2 (9alpha-acetoxyartecanin) and 8 (apressin) showed significant cytotoxic effects to all tested lines and inducumenone (9) exhibited a moderate activity. The most active was flavonol centaureidin (12), already known as cytotoxic compound.  相似文献   

12.
As little is known about the course of untreated epilepsy the time intervals between untreated tonic clonic seizures were examined retrospectively in a series of 183 patients presenting to a neurological department having had two to five seizures. After the first seizure a second attack had occurred within one month in 56 patients, within three months in 93, and within one year in 159. The median interval between the first two seizures was 12 weeks (95% confidence interval 10 to 18 weeks), between the second and third eight weeks (four to 12 weeks), between the third and fourth four weeks (two to 20 weeks), and between the fourth and fifth three weeks (one to four weeks). When patients who had had three, four, or five untreated seizures were considered separately a similar pattern of decreasing intervals was seen. Successive intervals between seizures could be compared in 82 patients. In 48 the interval decreased, in 16 it did not change, and in 18 it increased. These results suggest that in many patients there is an accelerating disease process in the early stages of epilepsy.  相似文献   

13.
Siddiqui BS  Ilyas F  Rasheed M  Begum S 《Phytochemistry》2004,65(14):2077-2084
The continued studies on the constituents of the fresh leaves and stem bark of Plumeria obtusa Linn. have led to the isolation and characterization of four new triterpenoids, dammara-12,20(22)Z-dien-3-one (1), dammara-12,20(22)Z-dien-3beta-ol (2), olean-12-en-3beta,27-diol (3), and 27-hydroxyolean-12-en-3-one (4) and 12 known compounds, which included eight triterpenoids; dammara-3beta,20(S),25-triol (5), urs-12-en-3beta-hydroxy-27-Z-feruloyloxy-28-oic acid (6), 3beta-hydroxyolean-12-en-28-oic acid (7), 3beta,27-dihydroxylupan-29-ene (8), 3beta-hydroxylupan-29-en-28-oic acid (9), 3beta-hydroxyursan-12-en-28-oic acid (11), 3beta-hydroxy-27-p-coumaroyloxy-olea-12-en-28-oic acid (12) and urs-12-en-3-one (15); an iridoid 1alpha-plumieride (10); a cardenolide 3alpha,14beta-dihydroxy-17beta-card-20(22)-enolide (13); a fatty acid ester methyl n-octadecanoate (14) and a steroid 3beta-hydroxy-delta5-stigmastane (16). The new constituents were characterized through spectroscopic studies including 1D (1H and 31C NMR) and 2D (COSY-45, NOESY, J-resolved, HMQC and HMBC) NMR and chemical transformations. This is the first report on the isolation of dammarane triterpenoids from P. obtusa. Compounds 5 and 6 are hitherto unreported from P. obtusa. The known compounds were identified by comparison of their spectral data with those reported in the literature.  相似文献   

14.
Tentative assignment of piebald trait gene to chromosome band 4q12   总被引:6,自引:0,他引:6  
Summary A case of de novo del(4)(q12q21.1) is presented. Three of four patients with comparable deletion show abnormal integumentary pigmentation, which is compatible with the known autosomal dominantly inherited piebald trait. Further analysis of breakpoints of five cases with proximal interstitial 4q deletion suggests the possible localization of the piebald trait gene within the band 4q12.Dedicated to Professor Dr. med. G. G. Wendt, a founding editor of the journal, on the occasion of his 65th birthday  相似文献   

15.
Katrin Linse 《Polar Biology》2006,29(2):120-127
Bouvet Island is one of the most isolated islands in the Southern Ocean and its marine benthic fauna has rarely been investigated and so is poorly known. This study adds 30 molluscan species to the previous faunal record of 16 species. During the expedition ANT XXI-2 of PFS Polarstern 25 species of shelled gastropods, 12 species of bivalves, 3 species of polyplacophorans and 1 species of solenogaster (Aplacophora) were collected at four sites around Bouvet Island in depths between 120 m and 550 m. High percentages of the species representing the shelled molluscan fauna of Bouvet Island are known from sub and high (continental) Antarctica.  相似文献   

16.
Four homeobox genes that belong to the four homeobox gene clusters known in mammals have been regionally assigned to four distinct porcine chromosomes in conserved regions between human and pig. HOXA11, HOXB6, HOXC8, and HOXD4 genes were mapped by radioactive in situ hybridization to porcine Chromosomes (Chrs) 18q21-24 (with a secondary signal in 16q14-21), 12p11-12, 5p11-12, and 15q22-23 respectively. Besides, we have also revealed the presence of a porcine homeobox (pig Hbx24) which, although showing DNA sequence homology with a mouse gene of HOXB cluster, was located on porcine Chr 3 (3p14-13) outside the Hox clusters. To support the identity of the homeobox gene clusters analyzed and in the light of the high sequence similarity among homeobox genes, we also localized markers known to be mapped near each Hox cluster in human. In this way, four genes were also mapped in pig: GAPD (5q12-21), GAD1 (15q21-22), INHBA (18q24), and IGFBP3 (18q24). Mapping of HOXA11, INHBA, and IGFBP3 on pig Chr 18 constitutes the first assignments of genes on this small chromosome. These new localizations extend the information on the conservation of four human chromosomal regions in the pig genome. Received: 7 August 1995 / Accepted: 16 October 1995  相似文献   

17.
Autosomal dominant pure hereditary spastic paraplegia (ADPHSP) is clinically characterized by slowly progressive lower-limb spasticity. The condition is genetically heterogeneous, and loci have been mapped at chromosomes 2p, 8q, 14q, and 15q. We have performed a genomewide linkage screen on a large family with ADPHSP, in which linkage to all four previously known loci was excluded. Analysis of markers on chromosome 12q gave a peak pairwise LOD score of 3.61 at D12S1691, allowing us to assign a new locus for ADPHSP (a locus that we have designated "SPG10") to this region. Haplotype construction and analysis of recombination events narrowed the SPG10 locus to a 9.2-cM region between markers D12S368 and D12S83. In addition, our data strongly suggest that there are at least six ADPHSP loci, since we describe a further family in which linkage to all five known ADPHSP loci has been excluded.  相似文献   

18.
Interruption of the enterohepatic circulation by cholestyramine causes a several-fold increase in bile acid synthesis, reflected in a stimulation of cholesterol 7 alpha-hydroxylase activity; the synthesis of cholic acid being stimulated to a greater extent than chenodeoxycholic acid. It is not known if this preferential increase in cholic acid is due to an increase of the 12 alpha-hydroxylase activity. The present study aimed at investigating the 12 alpha-hydroxylase activity and its relation to cholesterol 7 alpha-hydroxylase activity in liver microsomes of patients with different levels of cholesterol 7 alpha-hydroxylase activity. Liver biopsies were obtained from four gallstone-free patients, and seven untreated and two cholestyramine-treated gallstone patients undergoing cholecystectomy, and four patients with Crohn's disease undergoing intestinal resection. The combined group of cholestyramine-treated and ileum-resected patients had four times higher cholesterol 7 alpha-hydroxylase activity and two times higher 12 alpha-hydroxylase activity than the other patients. A positive correlation was obtained between cholesterol 7 alpha-hydroxylase activity and 12 alpha-hydroxylase activity (r = +0.69; n = 16). These results indicate that the increased ratio between the synthesis of cholic acid and chenodeoxycholic acid during cholestyramine treatment is due to a compensatory increase of the 12 alpha-hydroxylase activity.  相似文献   

19.
Bioactivity-guided fractionation on the leaves of Aleurites fordii led to the isolation of a new tigliane diterpene ester, 12-O-hexadecanoyl-7-oxo-5-ene-16-hydroxyphorbol-13-acetate (1) along with four known compounds, 12-O-hexadecanoyl-7-oxo-5-ene-phorbol-13-acetate (2), 12-O-hexadecanoyl-phorbol-13-acetate (3), 12-O-hexadecanoyl-16-hydroxyphorbol-13-acetate (4), and 12-O-hexadecanoyl-4-deoxy-4α-16-hydroxyphorbol-13-acetate (5). The structures of these compounds were determined by interpretation of NMR (1D and 2D) spectroscopic data and MS data. All the isolates were evaluated for their effects on the induction of IFN-γ in NK92 cells. Compounds 3 and 4 exhibited the most potent responses in IFN-γ induction, comparable to the positive control, phorbol 12-myristate 13-acetate (PMA).  相似文献   

20.
Non-lineage section studied in total 90 mAb samples, including 23 submitted as known CD specificities. Thirty four samples submitted as unknown and potentially novel specificities recognized actually well known molecules (HLA class I, CD7, 11b, 14, 18, 44, 45, 45RB, 47, 59, 62L, 71, 82, 147). Seven samples reacted with newly defined CD molecules (CD281, 282, 284, 298, 315, 316, 321) and specificities of 12 samples remained unresolved.  相似文献   

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