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31.
32.
Platelet-melanoma cell interaction is mediated by the glycoprotein IIb- IIIa complex 总被引:3,自引:0,他引:3
A human malignant melanoma cell line (M3Dau) was observed by electron microscopy to interact directly with human platelets and induced platelet aggregation. Fab fragments of a monoclonal antibody MoAb (LYP18), directed against the platelet glycoprotein (GP) IIb-IIIa complex, inhibited platelet-melanoma interactions and platelet-platelet aggregation. M3Dau melanoma cells bind LYP 18 and synthesize IIb-IIIa- like GPs. When the melanoma cells were preincubated with LYP 18, tumor- platelet interaction did not occur, suggesting that the interaction may be mediated by the IIb-IIIa-like GPs present on the melanoma cell surface. Glanzmann's thrombasthenic platelets, lacking GPIIb and IIIa, did not interact with melanoma cells, indicating that the platelet GPIIb-IIIa complex is also necessary for the platelet-melanoma cell interaction. This work demonstrates the importance of the IIb-IIIa-like GPs, present on M3Dau melanoma cells, in mediating tumor-platelet interactions. 相似文献
33.
Nayu Ikeda David Sapienza Ramiro Guerrero Wichai Aekplakorn Mohsen Naghavi Ali H Mokdad Rafael Lozano Christopher JL Murray Stephen S Lim 《Bulletin of the World Health Organization》2014,92(1):10-19C
Objective
To examine hypertension management across countries and over time using consistent and comparable methods.Methods
A systematic search identified nationally representative health examination surveys from 20 countries containing data from 1980 to 2011 on blood pressure measurements, the diagnosis and treatment of hypertension and its control with antihypertensive drugs. For each country, the prevalence of hypertension (i.e. systolic blood pressure ≥ 140 mmHg or antihypertensive use) and the proportion of hypertensive individuals whose condition was diagnosed, treated or controlled with medications (i.e. systolic pressure < 140 mmHg) were estimated.Findings
The age-standardized prevalence of hypertension varied between countries: for individuals aged 35 to 49 years, it ranged from around 12% in Bangladesh, Egypt and Thailand to around 30% in Armenia, Lesotho and Ukraine; for those aged 35 to 84 years, it ranged from 20% in Bangladesh to more than 40% in Germany, the Russian Federation and Turkey. The age-standardized percentage of hypertensive individuals whose condition was diagnosed, treated or controlled was highest in the United States of America: for those aged 35 to 49 years, it was 84%, 77% and 56%, respectively. Percentages were especially low in Albania, Armenia, the Islamic Republic of Iran and Turkey. Although recent trends in prevalence differed in England, Japan and the United States, treatment coverage and hypertension control improved over time, particularly in England.Conclusion
Globally the proportion of hypertensive individuals whose condition is treated or controlled with medication remains low. Greater efforts are needed to improve hypertension control, which would reduce the burden of noncommunicable diseases. 相似文献34.
35.
36.
37.
AMP-18,一种新发现的胃黏膜保护因子 总被引:3,自引:0,他引:3
AMP-18是一种新发现的由胃腺体上皮细胞合成的小分子蛋白质,独特表达于胃黏膜,机体其他部位少见,胃癌组织中表达缺失.AMP-18 由185个氨基酸组成,除去N端信号肽(20个氨基酸)后大小约18 ku,第54-150个氨基酸组成高度保守的结构域(BRICHOS区域)承担主要的生理功能.AMP-18由胃腺体上皮细胞以胞吐的方式分泌到胃黏液中,他的合成和分泌与个体生长发育有关,并受福斯高林、吲哚美辛、地塞米松等药物的影响.目前发现 AMP-18的生理功能主要有促进胃黏膜上皮细胞的有丝分裂,促进细胞的迁徙,促胃肠黏膜损伤的修复,保持胃肠黏膜的完整等. 相似文献
38.
Berge-Lefranc JL; Jay P; Massacrier A; Cau P; Mattei MG; Bauer S; Marsollier C; Berta P; Fontes M 《Human molecular genetics》1996,5(10):1637-1641
While constructing a cDNA library of human embryos, we have isolated a
clone homologous to jumonji, a mouse gene required for neural tube
formation. We have determined the complete coding sequence of the human
homologue (JMJ) and deduced the amino acid sequence of the putative
protein. We show here that human and mouse jumonji putative proteins are
homologous and present 90% identity. During human embryogenesis, JMJ mRNAs
are predominantly expressed in neurons and particularly in dorsal root
ganglion cells. They are also expressed in neurons of human adult cerebral
cortex. In view of these observations, we propose JMJ as a candidate gene
for developmental defects of the central nervous system in the human. The
human JMJ gene maps at position 6p24-6p23.
相似文献
39.
Screening for proteins with polyglutamine expansions in autosomal dominant cerebellar ataxias 总被引:2,自引:8,他引:2
Stevanin G; Trottier Y; Cancel G; Durr A; David G; Didierjean O; Burk K; Imbert G; Saudou F; Abada-Bendib M; Gourfinkel-An I; Benomar A; Abbas N; Klockgether T; Grid D; Agid Y; Mandel JL; Brice A 《Human molecular genetics》1996,5(12):1887-1892
Expansion of trinucleotide CAG repeats coding for polyglutamine has been
implicated in five neurodegenerative disorders, including spinocerebellar
ataxia (SCA) 1 and SCA3 or Machado-Joseph disease (SCA3/MJD), two forms of
type I autosomal dominant cerebellar ataxias (ADCA). Using the 1C2 antibody
which specifically recognizes large polyglutamine tracts, particularly
those that are expanded, we recently reported the detection of proteins
with pathological glutamine expansions in lymphoblasts from another form of
ADCA type I, SCA2, as well as from patients presenting with the distinct
phenotype of ADCA type II. We now have screened a large series of patients
with ADCA or isolated cases with cerebellar ataxia, for the presence of
proteins with polyglutamine expansions. A 150 kDa SCA2 protein was detected
in 16 out of 40 families with ADCA type I. This corresponds to 24% of all
ADCA type I families, which is much more frequent than SCA1 in this series
of patients (13%). The signal intensity of the SCA2 protein was negatively
correlated to age at onset, as expected for an expanded and unstable
trinucleotide repeat mutation. The disease segregated with markers closely
linked to the SCA2 locus in all identified SCA2 families. In addition, a
specific 130 kDa protein, which segregated with the disease, was detected
in lymphoblasts of patients from nine families with ADCA type II. It was
also visualized in the cerebral cortex of one of the patients,
demonstrating its translation in the nervous system. Finally, no new
disease-related proteins containing expanded polyglutamine tracts could be
detected in lymphoblasts from the remaining patients with ADCA or isolated
cases with cerebellar ataxia.
相似文献
40.
Ramesh JL. Kandimalla Prabhakar S Binukumar BK Willayat Yousuf Wani Deep Raj Sharma V.K. Grover Neerja Bhardwaj Kajal Jain Kiran Dip Gill 《Neuroscience letters》2011
Alzheimer's disease (AD) is the most common form of dementia, and is characterized by the degeneration of neurons and their synapses, and a higher number of amyloid plaques and neurofibrillary tangles (NFTs) compared with that found in non-demented individuals. Amyloid-β-peptides (Aβ) are major components of amyloid plaques in AD brain whereas NFTs are composed of Tau and associated with ubiquitin. The aim of the present study was to analyze the levels of Aβ42, hTau (total Tau) and ubiquitin in CSF of North Indian population. CSF Aβ42, Tau and ubiquitin were measured in CSF of AD patients as well as controls using ELISA assays. Here we report low Aβ42 levels in AD patients (324.24 ± 76.38 pg/ml) as compared to those in non-AD (NAD) (668.34 ± 43.13 pg/ml), neurological controls (NCs) (727.28 ± 46.49 pg/ml) and healthy controls (HCs) (976.47 ± 124.46 pg/ml). In contrast, hTau and ubiquitin levels were significantly high (568.65 ± 48.89 pg/ml and 36.82 ± 4.34 ng/ml, respectively) in AD patients compared to those in NAD, NC and HC. The hTau levels were 267.37 ± 36.64 pg/ml, 167.34 ± 44.27 pg/ml and 107.62 ± 24.27 pg/ml in NAD, NC and HC, respectively. Similarly, ubiquitin levels were 23.57 ± 2.32 ng/ml, 19.76 ± 3.64 ng/ml and 13.24 ± 4.56 ng/ml in NAD, NC and HC, respectively. In conclusion, low Aβ42 and high Tau–ubiquitin levels were found in North Indian AD patients. 相似文献