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61.
Saponins are steroid and triterpenoid glycosides that display diverse biological activities. The wide-spread occurrence in plants as well as the potential for pharmaceutical application has led to saponin extraction and identification in numerous species. Although these efforts are important to extend our knowledge of naturally occurring saponin structures, recent attention has been given to the biosynthesis and distribution in plants. In this review, we present recent advances on saponin production and distribution and highlight studies showing effects on the growth and development. 相似文献
62.
Victor X Jin Gregory AC Singer Francisco J Agosto-Pérez Sandya Liyanarachchi Ramana V Davuluri 《BMC bioinformatics》2006,7(1):114-13
Background
The canonical core promoter elements consist of the TATA box, initiator (Inr), downstream core promoter element (DPE), TFIIB recognition element (BRE) and the newly-discovered motif 10 element (MTE). The motifs for these core promoter elements are highly degenerate, which tends to lead to a high false discovery rate when attempting to detect them in promoter sequences. 相似文献63.
The health hazard associated with the consumption of fish from the Gomti River in India, contaminated with the heavy metals Cr, Cu, Mn, Ni, Pb, and Zn was assessed in terms of target hazard quotients (THQs). The concentrations of metals (mg kg?1, wet weight basis) in the muscle tissues of different fish species Mastacembelus puncalus, Clupisona garua, Cyrinous carpio, Botia lochachata, Channa punctatus, Heteropneustise fossilis, Puntius sofore, and Clarious batrachus ranged as follows: Cr (2.2–21.4), Cu (0.3–14.3), Mn (2.3–5.5), Ni (0.5–10.9), Pb (1.0–3.9), and Zn (12.3–46.9). The accumulation of metals in fish muscle tissue was in the order: Zn > Cr > Ni > Mn > Cu > Pb. THQs indicated a potential health hazard to children due to the consumption of fish contaminated with Ni and Pb; their THQs were greater than 1 for almost all fish species except for Ni in C. garua (THQ, 0.07) and C. carpio (THQ, 0.90). For adults, insignificant health hazard was associated with THQs less than 1 for all metals in the different fish species, but long-term exposure to these metals and subsequent bioaccumulation in the body may require additional investigation. 相似文献
64.
Christophe Rodriguez Cathia Soulié Anne-Geneviève Marcelin Vincent Calvez Diane Descamps Charlotte Charpentier Philippe Flandre Patricia Recordon-Pinson Pantxika Bellecave Jean-Michel Pawlotsky Bernard Masquelier the ANRS AC Study Group 《PloS one》2015,10(6)
Background
Maraviroc is an HIV entry inhibitor that alters the conformation of CCR5 and is poorly efficient in patients infected by viruses that use CXCR4 as an entry coreceptor. The goal of this study was to assess the capacity of ultra-deep pyrosequencing (UDPS) and different data analysis approaches to characterize HIV tropism at baseline and predict the therapeutic outcome on maraviroc treatment.Methods
113 patients with detectable HIV-1 RNA on HAART were treated with maraviroc. The virological response was assessed at months 1, 3 and 6. The sequence of the HIV V3 loop was determined at baseline and prediction of maraviroc response by different software and interpretation algorithms was analyzed.Results
UDPS followed by analysis with the Pyrotrop software or geno2pheno algorithm provided better prediction of the response to maraviroc than Sanger sequencing. We also found that the H34Y/S substitution in the V3 loop was the strongest individual predictor of maraviroc response, stronger than substitutions at positions 11 or 25 classically used in interpretation algorithms.Conclusions
UDPS is a powerful tool that can be used with confidence to predict maraviroc response in HIV-1-infected patients. Improvement of the predictive value of interpretation algorithms is possible and our results suggest that adding the H34S/Y substitution would substantially improve the performance of the 11/25/charge rule. 相似文献65.
Denusa M Veríssimo Renata FC Leit?o S?nia D Figueiró Júlio C Góes Vilma Lima Charles O Silveira Gerly AC Brito 《Experimental biology and medicine (Maywood, N.J.)》2015,240(2):175-184
The aim of this study was to evaluate the bone regenerative effect of glutaraldehyde (GA) cross-linking on mineralized polyanionic collagen membranes in critical-sized defects on rat calvarias. Bone calvarial defects were induced in Wistar rats, which were then divided into five groups: a sham group; a control group, which received a commercial membrane; and GA, 25GA, and 75GA groups, which received one of three different polyanionic collagen membranes mineralized by 0, 25, or 75 hydroxyapatite cycles and then cross-linked by GA. Bone formation was evaluated based on digital radiography and computerized tomography. Histological analyses were performed 4 and 12 weeks after the surgical procedure to observe bone formation, membrane resorption, and fibrous tissue surrounding the membranes. Measurement of myeloperoxidase activity, tumor necrosis factor alpha, and interleukin 1beta production was performed 24 h after surgery. The percentage of new bone formation in the GA, 25GA, and 75GA groups was higher compared with the control and sham groups. In the GA and 25 GA groups, the membranes were still in place and were contained in a thick fibrous capsule after 12 weeks. No significant difference was found among the groups regarding myeloperoxidase activity and interleukin 1beta levels, although the GA, 25GA, and 75GA groups presented decreased levels of tumor necrosis factor alpha compared with the control group. These new GA cross-linked membranes accelerated bone healing of the calvarium defects and did not induce inflammation. In addition, unlike the control membrane, the experimental membranes were not absorbed during the analyzed period, so they may offer advantages in large bone defects where prolonged membrane barrier functions are desirable. 相似文献
66.
Norfariza Jamaluddin Arbakariya B. Ariff Fadzlie Wong Faizal Wong 《Biotechnology progress》2019,35(1):e2719
Aqueous micellar two-phase system (AMTPS) is an extractive technique of biomolecule, where it is based on the differential partitioning behavior of biomolecule between a micelle-rich and a micelle-poor phase. In this study, an AMTPS composed of a nonionic surfactant, Triton X-100 (TX-100) was used for purifying a bacteriocin-like inhibitory substance (BLIS) derived from Pediococcus acidilactici Kp10. The influences of the surfactant concentration and the effect of additives on the partitioning behavior and activity yield of the BLIS were investigated. The obtained coexistence curves showed that the mixtures of solutions composed of different surfactant concentrations (5–30% w/w) and 50% w/w crude load were able to separate into two phases at temperatures of above 60 °C. The optimum conditions for BLIS partitioning using the TX-100-based AMTPS were: TX-100 concentration of 22.5% w/w, CFCS load of 50% w/w, incubation time of 30 min at 75 °C, and back-extraction using acetone precipitation. This optimal partitioning resulted in an activity yield of 64.3% and a purification factor of 5.8. Moreover, the addition of several additives, such as sorbitol, KCl, dioctyl sulfosuccinate sodium salt, and Coomassie® Brilliant Blue, demonstrated no improvement in the BLIS separation, except for Amberlite® resin XAD-4, where the activity yield was improved to 70.3% but the purification factor was reduced to 2.3. Results from this study have demonstrated the potential and applicability of TX-100-based AMTPS as a primary recovery method for the BLIS from a complex fermentation broth of P. acidilactici Kp10. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 35: e2719, 2019 相似文献
67.
Overbeek MJ Boonstra A Voskuyl AE Vonk MC Vonk-Noordegraaf A van Berkel MP Mooi WJ Dijkmans BA Hondema LS Smit EF Grünberg K 《Arthritis research & therapy》2011,13(2):R61-13
Introduction
Systemic sclerosis (SSc) complicated by pulmonary arterial hypertension (PAH) carries a poor prognosis, despite pulmonary vascular dilating therapy. Platelet-derived growth factor receptor-β (PDGFR-β) and epidermal growth factor receptor (EGFR) are potential therapeutic targets for PAH because of their proliferative effects on vessel remodelling. To explore their role in SScPAH, we compared PDGFR- and EGFR-mmunoreactivity in lung tissue specimens from SScPAH. We compared staining patterns with idiopathic PAH (IPAH) and pulmonary veno-occlusive disease (PVOD), as SScPAH vasculopathy differs from IPAH and sometimes displays features of PVOD. Immunoreactivity patterns of phosphorylated PDGFR-β (pPDGFR-β) and the ligand PDGF-B were evaluated to provide more insight into the patterns of PDGFR-b activation.Methods
Lung tissue specimens from five SScPAH, nine IPAH, six PVOD patients and five controls were examined. Immunoreactivity was scored for presence, distribution and intensity.Results
All SScPAH and three of nine IPAH cases (P = 0.03) showed PDGFR-β-immunoreactivity in small vessels (arterioles/venules); of five SScPAH vs. two of nine IPAH cases (P = 0.02) showed venous immunoreactivity. In small vessels, intensity was stronger in SScPAH vs. IPAH. No differences were found between SScPAH and PVOD. One of five normal controls demonstrated focally mild immunoreactivity. There were no differences in PDGF-ligand and pPDGFR-b-immunoreactivity between patient groups; however, pPDGFR-b-immunoreactivity tended to be more prevalent in SScPAH small vasculature compared to IPAH. Vascular EGFR-immunoreactivity was limited to arterial and arteriolar walls, without differences between groups. No immunoreactivity was observed in vasculature of normals.Conclusions
PDGFR-β-immunoreactivity in SScPAH is more common and intense in small- and post-capillary vessels than in IPAH and does not differ from PVOD, fitting in with histomorphological distribution of vasculopathy. PDGFR-β immunoreactivity pattern is not paralleled by pPDGFR-β or PDGF-B patterns. PDGFR-β- and EGFR-immunoreactivity of pulmonary vessels distinguishes PAH patients from controls. 相似文献68.
Nuclear actin - which is immunologically distinct from cytoplasmic actin - has been documented in a number of differentiated cell types, and cardiac isoforms of troponin I (cTnI) and troponin T (cTnT) have been detected in association with nuclei of adult human cardiac myocytes. It is not known whether these and related proteins are present in undifferentiated stem cells, or when they appear in cardiomyogenic cells following differentiation. We first tested the hypothesis that nuclear actin and cardiac isoforms of troponin C (cTnC) and tropomyosin (cTm) are present along with cTnI and cTnT in nuclei of isolated, neonatal rat cardiomyocytes in culture. We also tested the hypothesis that of these five proteins, only actin is present in nuclei of multipotent, bone marrow-derived mesenchymal stem cells (BM-MSCs) from adult rats in culture, but that cTnC, cTnI, cTnT and cTm appear early and uniquely following cardiomyogenic differentiation. Here we show that nuclear actin is present within nuclei of both ventricular cardiomyocytes and undifferentiated, multipotent BM-MSCs. We furthermore show that cTnC, cTnI, cTnT and cTm are not only present in myofilaments of ventricular cardiomyocytes in culture but are also within their nuclei; significantly, these four proteins appear between days 3 and 5 in both myofilaments and nuclei of BM-MSCs treated to differentiate into cardiomyogenic cells. These observations indicate that cardiac troponin and tropomyosin could have important cellular function(s) beyond Ca(2+)-regulation of contraction. While the roles of nuclear-associated actin, troponin subunits and tropomyosin in cardiomyocytes are not known, we anticipate that the BM-MSC culture system described here will be useful for elucidating their function(s), which likely involve cardiac-specific, Ca(2+)-dependent signaling in the nucleus. 相似文献
69.
Hennie G Raterman Alexandre E Voskuyl Ben AC Dijkmans Michael T Nurmohamed 《Arthritis research & therapy》2009,11(5):413-2
With great interest, we read the article by Toms and colleagues [1] in the previous issue of Arthritis Research & Therapy, in which they assessed prevalences of metabolic syndrome (MetS) in rheumatoid arthritis (RA) patients. Moreover, they identified demographic and clinical factors that may be associated with MetS. Toms and colleagues found prevalences of up to 45% of MetS and demonstrated older age and health status (health assessment questionnaire) to be associated with MetS irrespectively of the definition used. Of most interest, an association between methotrexate (MTX) use and decreased presence of MetS was observed in patients more than 60 years of age. The investigators hypothesized that this may be attributed to a drug-specific effect (and not to an anti-inflammatory effect) either by changing levels of adenosine, which is known to interact with glucose and lipid metabolism, or by an indirect effect mediated through concomitant folic acid administration, thereby decreasing homocysteine levels.Recently, we also examined the prevalence of MetS in (a subgroup of) RA patients in the CARRÉ investigation, a prospective cohort study on prevalent and incident cardiovascular disease and its underlying cardiovascular risk factors [2]. The findings of Toms and colleagues stimulated us to perform additional analyses in our total study population (n = 353).The prevalences of MetS were 35% and 25% (Table (Table1)1) according to criteria of National Cholesterol Education Program (NCEP) 2004 and NCEP 2001, respectively. In multivariate backward regression analyses, we found significant associations between body mass index, pulse rate, creatinine levels, hypothyroidism and diabetes mellitus and the presence of MetS independently of the criteria used (Table (Table2).2). However, an independent association between single use of MTX or use of MTX in combination with other disease-modifying antirheumatic drugs, on the one hand, and a decreased prevalence of MetS, on the other hand, could not be demonstrated (even in the subgroup of patients over the age of 60).
Open in a separate windowaMetabolic syndrome (MetS) according to National Cholesterol Education Program (NCEP) 2001; bMetS according to NCEP 2004. Continuous variables are presented as means (± standard deviations) in cases of normal distribution or as medians (interquartile ranges) in cases of non-normal distribution. BMI, body mass index; CRP, C-reactive protein; DAS28, disease activity score using 28 joint counts; DMARD, disease-modifying antirheumatic drug; ESR, erythrocyte sedimentation rate; HCQ, hydroxychloroquine; MTX, methotrexate; RA, rheumatoid arthritis; SSZ, sulfasalazine; TNF, tumour necrosis factor.
Open in a separate windowaIn multivariate analyses, the following variables were used: gender, age, prednisolone only, methotrexate only, sulfasalazine only, hydroxychloroquine only, tumour necrosis factor-blocking agents, combination of disease-modifying antirheumatic drugs, pack-years, smoking, erosions, DAS28 (disease activity score using 28 joint counts), body mass index, pulse rate, creatinine levels, renal clearance, hypothyroidism and diabetes mellitus. CI, confidence interval; OR, odds ratio.Therefore, to get more support for a drug-specific effect, it is of interest to know whether or not in the study of Toms and colleagues the MTX effect was present only in the group of RA patients with single use of MTX or in the group of MTX-treated patients with other antirheumatic drugs. As patients with MetS were significantly older, it would give further information whether age was an independent risk factor for MetS in regression analyses. Moreover, as readers, we are not informed about comorbidities like diabetes and clinical hypothyroidism, which are notorious cardiometabolic risk factors. On the whole, we could not confirm a plausible protective role for the use of MTX and presence of MetS, and hence further investigation is required to explain the discrepancy between our findings and those of Toms and colleagues. 相似文献
Table 1
Characteristics of the study populationMetS presenta | MetS absenta | MetS presentb | MetS absentb | |||
---|---|---|---|---|---|---|
n = 84 | n = 265 | n = 121 | n = 228 | P valuea | P valueb | |
Demographics | ||||||
Age, years | 63.8 (± 8) | 63.1 (± 7) | 64.3 (± 8) | 62.7 (± 7) | 0.46 | 0.045 |
Female, percentage | 76 | 63 | 74 | 62 | 0.022 | 0.028 |
RA-related characteristics | ||||||
DAS28 | 4.2 (± 1.3) | 3.9 (± 1.4) | 4.1 (± 1.3) | 3.8 (± 1.4) | 0.21 | 0.062 |
ESR, mm/hour | 22 (10-35) | 16 (9-30) | 20 (10-34) | 17 (9-31) | 0.059 | 0.33 |
CRP, mg/L | 11 (4-21) | 6 (3-16) | 8 (3-18) | 6 (3-19) | 0.021 | 0.46 |
RA duration, years | 7 (4-10) | 7 (4-10) | 7 (4-10) | 7 (5-10) | 0.83 | 0.19 |
Erosion, percentage | 77 | 83 | 79 | 83 | 0.20 | 0.36 |
Number of DMARDs | 1 (1-2) | 1 (1-1) | 1 (1-2) | 1 (1-1) | 0.26 | 0.43 |
MTX current, percentage | 62 | 60 | 63 | 59 | 0.71 | 0.46 |
MTX only, percentage | 39 | 39 | 41 | 38 | 0.95 | 0.67 |
SSZ only, percentage | 8 | 13 | 9 | 14 | 0.23 | 0.22 |
HCQ only, percentage | 1 | 4 | 3 | 4 | 0.31 | 0.55 |
Combination of DMARDs, percentage | 31 | 25 | 29 | 25 | 0.24 | 0.38 |
TNF-blocking agent, percentage | 11 | 9 | 11 | 9 | 0.73 | 0.65 |
Prednisolone only, percentage | 1 | 2 | 3 | 1 | 1.00 | 0.42 |
Cardiovascular risk factors | ||||||
Current smoker, percentage | 26 | 31 | 25 | 32 | 0.42 | 0.15 |
Pack-years, years | 17 (0-34) | 19 (2-38) | 19 (0-35) | 18 (2-38) | 0.23 | 0.75 |
BMI, kg/m2 | 30 (± 4) | 26 (± 5) | 29 (± 4) | 25 (± 5) | < 0.001 | < 0.001 |
Creatinine, μmol/L | 89 (± 21) | 89 (± 16) | 91 (± 22) | 87 (± 14) | 0.99 | 0.070 |
Renal clearance, mL/minute | 81 (± 24) | 72 (± 19) | 77 (± 23) | 73 (± 19) | 0.003 | 0.062 |
Pulse, beats per minute | 76 (± 11) | 73 (± 9) | 75 (± 11) | 73 (± 9) | 0.005 | 0.015 |
Diabetes mellitus, percentage | 14 | 3 | 12 | 3 | < 0.001 | 0.001 |
Hypothyroidism, percentage | 12 | 2 | 9 | 2 | 0.001 | 0.003 |
Table 2
Variables associated with metabolic syndromeUnivariate | Multivariatea | |||||
---|---|---|---|---|---|---|
OR | 95% CI | P value | OR | 95% CI | P value | |
Body mass index | 1.2 | 1.1-1.3 | < 0.001 | 1.2 | 1.1-1.3 | < 0.001 |
Pulse | 1.03 | 1.01-1.06 | 0.011 | 1.03 | 1.00-1.06 | 0.020 |
Creatinine | 1.01 | 1.00-1.02 | 0.080 | 1.02 | 1.00-1.03 | 0.017 |
Hypothyroidism | 4.5 | 1.5-13.2 | 0.007 | 4.7 | 1.5-15.0 | 0.009 |
Diabetes mellitus | 4.8 | 1.8-12.9 | 0.002 | 4.5 | 1.4-15.2 | 0.014 |
70.
Jennie Ursum Wouter H Bos Rob J van de Stadt Ben AC Dijkmans Dirkjan van Schaardenburg 《Arthritis research & therapy》2009,11(3):R75-6