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91.
朊病毒疾病即海绵状脑病,是人的动物中的一类致死性中央神经系统疾病,介绍了朊病毒疾病的诊断技术,病理诊断,基因诊断,免疫诊断和血液检测。 相似文献
92.
Melanoma is one of the most common skin cancer that is characterized by rapid growth, early metastasis, high malignant, and mortality. Accumulating evidence demonstrated that promoter methylation of tumor-suppressor genes is implicated in the pathogenesis of melanoma. In the current study, we performed a meta-analysis to identify promising methylation biomarkers in the diagnosis of melanoma. We carried out a systematic literature search using Pubmed, Embase, and ISI web knowledge database and found that gene promoter methylation of 50 genes was reported to be associated with the risk of melanoma. Meta-analysis revealed that hypermethylation of claudin 11 (CLDN11; odds ratio [OR], 16.82; 95% confidence interval [CI], 1.97–143.29; p = 0.010), O-6-methylguanine-DNA methyltransferase (MGMT; OR, 5.59; 95% CI, 2.51–12.47; p < 0.0001), cyclin-dependent kinase inhibitor 2A (p16; OR, 6.57; 95% CI, 2.19–19.75; p = 0.0008), retinoic acid receptor β (RAR-β2; OR, 24.31; 95% CI, 4.58–129.01; p = 0.0002), and Ras association domain family member (RASSF1A; OR, 9.35; 95% CI, 4.73–18.45; p < 0.00001) was significantly higher in melanoma patients compared with controls. CLDN11 (OR, 14.52; 95% CI, 1.84–114.55; p = 0.01), MGMT (OR, 8.08; 95% CI, 1.84–35.46; p = 0.006), p16 (OR, 9.44; 95% CI, 2.68–33.29; p = 0.0005), and RASSF1A (OR, 7.72; 95% CI, 1.05–56.50; p = 0.04) hypermethylation was significantly increased in primary melanoma compared with controls. Methylation frequency of CLDN11 (OR, 25.56; 95% CI, 2.32–281.66; p = 0.008), MGMT (OR, 4.64; 95% CI, 1.98–10.90; p = 0.0004), p16 (OR, 4.31; 95% CI, 1.33–13.96; p = 0.01), and RASSF1A (OR, 10.10; 95% CI, 2.87–35.54; p = 0.0003) was significantly higher in metastasis melanoma compared with controls. These findings indicated that CLDN11, MGMT, p16, RAR-β2, and RASSF1A hypermethylation is a risk factor and a potential biomarker for melanoma. CLDN11, MGMT, p16, and RASSF1A promoter methylation may take part in the development of melanoma and become useful biomarkers in the early diagnosis of the disease. 相似文献
93.
Six new species of the spider genus Spiricoelotes Wang, 2002 are described, Spiricoelotes
anshiensis Chen & Li, sp. n. (♂♀), Spiricoelotes
chufengensis Chen & Li, sp. n. (♂♀), Spiricoelotes
nansheensis Chen & Li, sp. n. (♂♀), Spiricoelotes
taipingensis Chen & Li, sp. n. (♂♀), Spiricoelotes
xianheensis Chen & Li, sp. n. (♂♀) and Spiricoelotes
xiongxinensis Chen & Li, sp. n. (♀). All new species were collected from caves in Jiangxi Province, China. 相似文献
94.
Anand Bery Felix Leung Christopher R Smith Eleftherios P Diamandis Vathany Kulasingam 《Clinical proteomics》2014,11(1):13
Background
Conventional proteomic approaches have thus far been unable to identify novel serum biomarkers for ovarian cancer that are more sensitive and specific than the current clinically used marker, CA-125. Because endogenous peptides are smaller and may enter the circulation more easily than proteins, a focus on the low-molecular-weight region may reveal novel biomarkers with enhanced sensitivity and specificity. In this study, we deciphered the peptidome of ascites fluid from 3 ovarian cancer patients and 3 benign individuals (ascites fluid from patients with liver cirrhosis).Results
Following ultrafiltration of the ascites fluids to remove larger proteins, each filtrate was subjected to solid phase extraction and fractionated using strong cation exchange chromatography. The resultant fractions were analyzed using an Orbitrap mass spectrometer. We identified over 2000 unique endogenous peptides derived from 259 proteins. We then catalogued over 777 peptides that were found only in ovarian cancer ascites. Our list of peptides found in ovarian cancer specimens includes fragments derived from the proteins vitronectin, transketolase and haptoglobin.Conclusions
Peptidomics may uncover previously undiscovered disease-specific endogenous peptides that warrant further investigation as biomarkers for ovarian cancer. 相似文献95.
Teresa Pérez Antoni Gómez Raimon Sanmarti Odette Vi?as Guadalupe Ercilla Isabel Haro 《Letters in Peptide Science》2002,9(6):291-300
Antifilaggrin autoantibodies (AFA) have described to be the most specific markers of rheumatoid arthritis (RA) and epitopes containing citrulline within the sequence of filaggrin identified as major antigenic sites recognised by AFA. In this paper we confirm that citrulline is an essential constituent of filaggrin related antigenic determinants recognised by RA specific autoantibodies, thus having an important role for the development of filaggrin peptides based serological tests. Moreover, we describe our findings on the comparative conformational analysis of filaggrin (306–324) peptide sequence and an analogue in which two arginines were simultaneously substituted by citrulline carried out by Circular Dichroism (CD) and Fourier-Transform Infrared Spectroscopy (FTIR). Results might contribute to the understanding of the structural features that may be important to explain the enhanced binding characteristics of citrullinated peptides to the autoantibodies in rheumatoid arthritis. 相似文献
96.
97.
98.
Prithwiraj De Anita G. Amin Danara Flores Anne Simpson Karen Dobos Delphi Chatterjee 《The Journal of biological chemistry》2021,297(5)
In Mycobacterium tuberculosis (Mtb), surface-exposed Lipoarabinomannan (LAM) is a key determinant of immunogenicity, yet its intrinsic heterogeneity confounds typical structure–function analysis. Recently, LAM gained a strong foothold as a validated marker for active tuberculosis (TB) infection and has shown great potential in new diagnostic efforts. However, no efforts have yet been made to model or evaluate the impact of mixed polyclonal Mtb infections (infection with multiple strains) on TB diagnostic procedures other than antibiotic susceptibility testing. Here, we selected three TB clinical isolates (HN878, EAI, and IO) and purified LAM from these strains to present an integrated analytical approach of one-dimensional and two-dimensional Nuclear Magnetic Resonance (NMR) spectroscopy, as well as enzymatic digestion and site-specific mass spectrometry (MS) to probe LAM structure and behavior at multiple levels. Overall, we found that the glycan was similar in all LAM preparations, albeit with subtle variations. Succinates, lactates, hydroxybutyrate, acetate, and the hallmark of Mtb LAM-methylthioxylose (MTX), adorned the nonreducing terminal arabinan of these LAM species. Newly identified acetoxy/hydroxybutyrate was present only in LAM from EAI and IO Mtb strains. Notably, detailed LC/MS-MS unambiguously showed that all acyl modifications and the lactyl ether in LAM are at the 3-OH position of the 2-linked arabinofuranose adjacent to the terminal β-arabinofuranose. Finally, after sequential enzymatic deglycosylation of LAM, the residual glycan that has ∼50% of α−arabinofuranose -(1→5) linked did not bind to monoclonal antibody CS35. These data clearly indicate the importance of the arabinan termini arrangements for the antigenicity of LAM. 相似文献
99.
100.
J. De Kok C. Van Der Schoot M. Veldhuizen H. Th. Wolterbeek 《Biological trace element research》1993,38(1):13-26
The in vitro uptake of zinc by erythrocytes was measured under near-physiological conditions, using65Zn as a radioactive tracer. Because of the presence of serum albumin—a strong zinc ligand—a low concentration of medium free
zinc was maintained. Under these conditions a high-affinity carrier for zinc transport over the cell membrane was identified.
With human erythrocytes, a Michaelis constant (K
m
) of 0.2 nM with respect to free medium zinc was measured and aV
max
of 4.5 nmoles Zn transported per h/g dry wt. TheK
m
for medium Zn increases when the size of the internal erythrocytic Zn pool is augmented, whereasV
max
remains virtually unchanged. A model to explain this phenomenon is proposed. It is suggested that this phenomenon could underlie
observations, confirmed here, that the in vitro uptake of Zn by animal erythrocytes depends on the Zn status of the animal. 相似文献