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31.
Gracilaria is a red seaweed that has been cultivated worldwide and is commercially used for food, fertilizers, animal fodder, and phycocolloids. However, the high morphological plasticity of seaweeds often leads to the misidentification in the traditional identification of Gracilaria species. Molecular markers are important especially in the correct identification of Gracilaria species with high economic value. Microsatellite markers were developed from the expressed sequence tags of seaweeds deposited at the National Center for Biotechnology Information database and used for differentiating Gracilaria changii collected at various localities and two other Gracilaria species. Out of 33 primer pairs, only one primer pair gave significant results that can distinguish between three different Gracilaria species as well as G. changii from various localities based on the variation in repeated nucleotides. The unweighted pair group method using arithmetic mean dendrogram analysis grouped Gracilaria species into five main clades: (a) G. changii from Batu Besar (Malacca), Sandakan (Sabah), Bintulu (Sarawak), Batu Tengah (Malacca), Gua Tanah (Malacca), Middle Banks (Penang), Sungai (Sg.) Merbok (Kedah), Teluk Pelandok (Negeri Sembilan), Pantai Dickson (Negeri Sembilan), Sg. Kong-Kong (Johore), and Sg. Pulai (Johore); (b) Gracilaria manilaensis from Cebu, Philippines; (c) G. changii from Morib (Selangor); (d) Gracilaria fisheri from Pattani, Thailand; and (e) G. changii from Pantai Dickson (Negeri Sembilan), Gua Tanah (Malacca), Sg. Merbok (Kedah), Sg. Kong-Kong (Johore), and Sg. Pulai (Johore). This result shows that this primer pair was able to distinguish between three different species, which are G. changii from Morib (Malaysia), G. fisheri from Pattani (Thailand), and G. manilaensis from Cebu (Philippines), and also between different genotypes of G. changii. This suggested that the simple sequence repeat primer we developed was suitable for differentiating between different Gracilaria species due to the polymorphisms caused by the variability in the number of tandem repeats.  相似文献   
32.
Systems neuroscience has identified a set of canonical large-scale networks in humans. These have predominantly been characterized by resting-state analyses of the task-unconstrained, mind-wandering brain. Their explicit relationship to defined task performance is largely unknown and remains challenging. The present work contributes a multivariate statistical learning approach that can extract the major brain networks and quantify their configuration during various psychological tasks. The method is validated in two extensive datasets (n = 500 and n = 81) by model-based generation of synthetic activity maps from recombination of shared network topographies. To study a use case, we formally revisited the poorly understood difference between neural activity underlying idling versus goal-directed behavior. We demonstrate that task-specific neural activity patterns can be explained by plausible combinations of resting-state networks. The possibility of decomposing a mental task into the relative contributions of major brain networks, the "network co-occurrence architecture" of a given task, opens an alternative access to the neural substrates of human cognition.  相似文献   
33.
Ch14.18 manufactured in Chinese hamster ovary (CHO) cells is currently being evaluated in clinical trials. Short-term infusion (STI) (8–20 h/day; 4–5 days) of 100 mg/m2 ch14.18/CHO (dinutiximab β) per cycle in combination with cytokines is standard treatment of neuroblastoma (NB) patients. As pain is a limiting factor, we investigated a novel delivery method by continuous long-term infusion (LTI) of 100 mg/m2 over 10 days. 53 NB patients were treated with 5–6 cycles of 6 × 106 IU/m2 subcutaneous interleukin-2 (d 1-5, 8-12), LTI of 100 mg/m2 ch14.18/CHO (d 8-18) and 160 mg/m2 oral 13-cis-retinoic acid (d 22-35). Human anti-chimeric antibody (HACA), antibody-dependent cell-mediated cytotoxicity and complement-dependent cytotoxicity were determined. With LTI, we observed a maximum concentration of ch14.18/CHO (Cmax) of 12.56 ± 0.68 µg/ml and a terminal half-life time (t1/2 β) of 32.7 ± 16.2 d. The clearance values for LTI and STI of 0.54 ± 0.13 and 0.41 ± 0.29 L/d m2 and area under the serum concentration-time curve (AUC) values of 189.6 ± 41.4 and 284.8 ± 156.8 µg×d/ml, respectively, were not significantly different. Importantly, we detected ch14.18/CHO trough concentration of ≥ 1 µg/ml at time points preceding subsequent antibody infusions after cycle 1, allowing a persistent activation of antibody effector mechanisms over the entire treatment period of 6 months. HACA responses were observed in 10/53 (19%) patients, similar to STI (21%), indicating LTI had no effect on the immunogenicity of ch14.18/CHO. In conclusion, LTI of ch14.18/CHO induced effector mechanisms over the entire treatment period, and may therefore emerge as the preferred delivery method of anti-GD2 immunotherapy to NB patients.  相似文献   
34.

Background

Impaired renal function causes dyslipidemia that contributes to elevated cardiovascular risk in patients with chronic kidney disease (CKD). The proprotein convertase subtilisin/kexin type 9 (PCSK9) is a regulator of the LDL receptor and plasma cholesterol concentrations. Its relationship to kidney function and cardiovascular events in patients with reduced glomerular filtration rate (GFR) has not been explored.

Methods

Lipid parameters including PCSK9 were measured in two independent cohorts. CARE FOR HOMe (Cardiovascular and Renal Outcome in CKD 2–4 Patients—The Forth Homburg evaluation) enrolled 443 patients with reduced GFR (between 90 and 15 ml/min/1.73 m2) referred for nephrological care that were prospectively followed for the occurrence of a composite cardiovascular endpoint. As a replication cohort, PCSK9 was quantitated in 1450 patients with GFR between 90 and 15 ml/min/1.73 m2 enrolled in the Ludwigshafen Risk and Cardiovascular Health Study (LURIC) that were prospectively followed for cardiovascular deaths.

Results

PCSK9 concentrations did not correlate with baseline GFR (CARE FOR HOMe: r = -0.034; p = 0.479; LURIC: r = -0.017; p = 0.512). 91 patients in CARE FOR HOMe and 335 patients in LURIC reached an endpoint during a median follow-up of 3.0 [1.8–4.1] years and 10.0 [7.3–10.6] years, respectively. Kaplan-Meier analyses showed that PCSK9 concentrations did not predict cardiovascular events in either cohort [CARE FOR HOMe (p = 0.622); LURIC (p = 0.729)]. Sensitivity analyses according to statin intake yielded similar results.

Conclusion

In two well characterized independent cohort studies, PCSK9 plasma levels did not correlate with kidney function. Furthermore, PCSK9 plasma concentrations were not associated with cardiovascular events in patients with reduced renal function.  相似文献   
35.
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37.
Bats broadcast rapid sequences of echolocation calls, named ‘drinking buzzes’, when they approach water to drink on the wing. So far this phenomenon has received little attention. We recorded echolocation sequences of drinking bats for 12 species, for 11 of which we also recorded feeding buzzes. Based on the different sensorial tasks faced by feeding and drinking bats, we hypothesize that the drinking buzz structure will differ from that of feeding buzzes since unlike the latter drinking buzzes are not designed to detect and track mobile prey. We demonstrated that drinking buzzes are structurally different from feeding buzzes. We show that the buzz‐II phase common in feeding buzzes is absent in drinking buzzes; that is, call frequency is not lowered to broaden sonar beam since the task of drinking does not imply tracking fast‐moving targets. This finding indirectly confirms the role of buzz II in feeding buzzes. Pulse rate in drinking buzzes is also lower than in feeding buzzes, as predicted since the high pulse rate typical of feeding buzzes is important to update rapidly the relative location of moving targets. The most likely function of drinking buzzes is to guide a safe drinking manoeuvre, similar to ‘landing buzzes’ broadcast when bats land on the ground.  相似文献   
38.
The liver is the most important organ in cholesterol metabolism, which is instrumental in regulating cell proliferation and differentiation. The gene Tm7sf2 codifies for 3 β-hydroxysterol-Δ14-reductase (C14-SR), an endoplasmic reticulum resident protein catalyzing the reduction of C14-unsaturated sterols during cholesterol biosynthesis from lanosterol. In this study we analyzed the role of C14-SR in vivo during cell proliferation by evaluating liver regeneration in Tm7sf2 knockout (KO) and wild-type (WT) mice. Tm7sf2 KO mice showed no alteration in cholesterol content. However, accumulation and delayed catabolism of hepatic triglycerides was observed, resulting in persistent steatosis at all times post hepatectomy. Moreover, delayed cell cycle progression to the G1/S phase was observed in Tm7sf2 KO mice, resulting in reduced cell division at the time points examined. This was associated to abnormal ER stress response, leading to alteration in p53 content and, consequently, induction of p21 expression in Tm7sf2 KO mice. In conclusion, our results indicate that Tm7sf2 deficiency during liver regeneration alters lipid metabolism and generates a stress condition, which, in turn, transiently unbalances hepatocytes cell cycle progression.  相似文献   
39.
Objective: The early identification of gastric cancer (GC) represents a major clinical challenge. We conducted a systematic review of studies evaluating the miRNA expression profiling as a diagnostic tool in GC.

Methods: We performed a search of PubMed, ISI Web of Science and SCOPUS databases for studies on diagnostic miRNAs and GC, published in English up to October 2017. Eligibility criteria included case-control studies evaluating blood or tissue-based miRNA expression profiles, and incorporating at least two detection phases (screening and validation).

Results: We included 27 eligible studies, that reported on 97 deregulated miRNAs either in blood or tissue, out of which 30 were reported in at least two studies. Among 22 studies on tissue-diagnostic miRNAs, 13 consistently upregulated miRNAs (miR-214, miR-21, miR-103, miR-107, miR-196a, miR-196b, miR-7, miR-135b, miR-222, miR-23b, miR-25, miR-92 and miR-93), and six consistently downregulated miRNAs (miR-148a, miR-375, miR-133b, miR-30a, miR-193a and miR-204) were reported. Ten miRNAs with inconsistent direction of expression in tissues were identified. Among the five studies performed on blood samples, only one miRNA was consistently upregulated (miR-20a).

Conclusions: This review shows that some tissue or blood miRNAs may be considered as potential biomarkers for GC diagnosis, that urgently needs to be confirmed from large prospective studies.  相似文献   

40.
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