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131.
The maturity of green coffee beans is the most influential determinant of the quality and flavor of the resultant coffee beverage. However, the chemical compounds that can be used to discriminate the maturity of the beans remain uncharacterized. We herein analyzed four distinct stages of maturity (immature, semi-mature, mature and overripe) of nine different varieties of green Coffea arabica beans hand-harvested from a single experimental field in Hawaii. After developing a high-throughput experimental system for sample preparation and liquid chromatography-mass spectrometry (LC-MS) measurement, we applied metabolic profiling, integrated with chemometric techniques, to explore the relationship between the metabolome and maturity of the sample in a non-biased way. For the multivariate statistical analyses, a partial least square (PLS) regression model was successfully created, which allowed us to accurately predict the maturity of the beans based on the metabolomic information. As a result, tryptophan was identified to be the best contributor to the regression model; the relative MS intensity of tryptophan was higher in immature beans than in those after the semi-mature stages in all arabica varieties investigated, demonstrating a universal discrimination factor for diverse arabica beans. Therefore, typtophan, either alone or together with other metabolites, may be utilized for traders as an assessment standard when purchasing qualified trading green arabica bean products. Furthermore, our results suggest that the tryptophan metabolism may be tightly linked to the development of coffee cherries and/or beans.  相似文献   
132.
An array of lipidic compounds that constitute the cell wall of mycobacteria is recognized by host receptors. Examples include trehalose dimycolate (TDM), which is a major surface-exposed glycolipid of mycobacteria, that interacts with the macrophage inducible C-type lectin, Mincle, and exerts its highly potent adjuvant functions. Recent evidence has suggested that glycerol monomycolate (GroMM), another mycolate-containing lipid species produced by mycobacteria, can stimulate innate immune cells; however, its specific host receptors have yet to be identified. We here demonstrated that cell transfectants expressing human Mincle (hMincle) reacted to both TDM and GroMM, while those expressing mouse Mincle (mMincle) only reacted to TDM and failed to recognize GroMM. Studies using domain swap chimeras confirmed that the ectodomain of hMincle, but not that of mMincle, interacted with GroMM, and site-directed mutagenesis analyses revealed that short stretches of amino acid residues at positions 174–176 and 195–196 were involved in GroMM recognition. To further substantiate the differential recognition of GroMM by hMincle and mMincle, hMincle transgenic/mMincle knock-out mice (i.e. hMincle+ mice) were established and compared with non-transgenic mice (i.e. mMincle+ mice). We showed that macrophages derived from hMincle+ mice were activated by GroMM and produced inflammatory cytokines, whereas those derived from mMincle+ mice did not exhibit any reactivity to GroMM. Furthermore, local inflammatory responses were elicited in the GroMM-injected skin of hMincle+, but not mMincle+ mice. These results demonstrated that GroMM is a unique ligand for hMincle that is not recognized by mMincle.  相似文献   
133.
Location of the disulfide bonds connecting three polypeptide chains (alpha 3, 27kd; 2, 43kd; beta, 75kd) of C3c has been investigated by partial reduction with cysteine followed by alkylation with 14C-monoiodoacetic acid. Treatment of C3c with cysteine produced a partially reduced fragment, composed of disulfide-linked beta and alpha 3 chains. A single thiol residue was detected on the alpha 3 chain but not on the beta chain of the fragment, suggesting that the alpha 2 chain in C3c is linked through a single disulfide bond to the alpha 3 chain but not to the beta chain.  相似文献   
134.
The Drosophila visual system consists of the compound eyes and the optic ganglia in the brain. Among the eight photoreceptor (R) neurons, axons from the R1-R6 neurons stop between two layers of glial cells in the lamina, the most superficial ganglion in the optic lobe. Although it has been suggested that the lamina glia serve as intermediate targets of R axons, little is known about the mechanisms by which these cells develop. We show that DPP signaling plays a key role in this process. dpp is expressed at the margin of the lamina target region, where glial precursors reside. The generation of clones mutant for Medea, the DPP signal transducer, or inhibition of DPP signaling in this region resulted in defects in R neuron projection patterns and in the lamina morphology, which was caused by defects in the differentiation of the lamina glial cells. glial cells missing/glial cells deficient (gcm; also known as glide) is expressed shortly after glia precursors start to differentiate and migrate. Its expression depends on DPP; gcm is reduced or absent in dpp mutants or Medea clones, and ectopic activation of DPP signaling induces ectopic expression of gcm and REPO. In addition, R axon projections and lamina glia development were impaired by the expression of a dominant-negative form of gcm, suggesting that gcm indeed controls the differentiation of lamina glial cells. These results suggest that DPP signaling mediates the maturation of the lamina glia required for the correct R axon projection pattern by controlling the expression of gcm.  相似文献   
135.
6-O-acyl-muramyldipeptides (MDP) with various lengths of fatty acid chains were examined for their dendritic cell (DC) maturation activity expressed through TLRs. Judging from anti-TLR mAb/inhibitor-blocking analysis, MDP derivatives with a single octanoyl or stearoyl fatty acid chain were found to activate TLR2 and TLR4 on human DCs, although intact and diacylated MDP expressed no ability to activate TLRs. Human DC activation profiles by the monoacylated MDP were essentially similar to those by Calmette-Guerin (BCG)-cell wall skeleton (CWS) and BCG-peptidoglycan (PGN) based on their ability to up-regulate costimulators, HLA-DR, beta(2)-microglobulin, and allostimulatory MLR. Monoacylated MDP induced cytokines with similar profiles to BCG-CWS or -PGN, although their potency for induction of TNF-alpha, IL-12p40, and IL-6 was less than that of BCG-CWS or -PGN. The MDP derivatives initiated similar activation in normal mouse macrophages, but exhibited no effect on TLR2/4-deficient or MyD88-deficient mouse macrophages. Mutation of d-isoGln to l-isoGln in monoacylated MDP did not result in loss of the DC maturation activity, suggesting marginal participation of nucleotide-binding oligomerization domain 2, if any, in monoacyl MDP-dependent DC maturation. These results define the adjuvant activity of 6-O-acyl MDP compounds at the molecular level. They target TLR2/TLR4 and act through the MyD88-dependent pathway in DCs and macrophages. Hence, the unusual combined activation of TLR2 and TLR4 observed with Mycobacterium tuberculosis is in part reflected in the functional properties of monoacylated MDP compounds. These findings infer that the essential minimal requirement for TLR2/4-mediated adjuvancy of BCG lies within a modified MDP.  相似文献   
136.

Purpose

We investigated that preoperative membranous urethral length (MUL) would be associated with the recovery of urinary continence after robot-assisted laparoscopic prostatectomy (RALP).

Patients and methods

We studied 204 patients who underwent RALP between May 2013 and March 2016. All patients underwent pelvic magnetic resonance imaging (MRI) preoperatively to measure MUL. Urinary continence was defined as the use of one pad or less (safety pad). The 204 patients were divided into two groups: continence group, those who achieved recovery of continence at 3, 6, and 12?months after RALP, and incontinence group, those who did not. We retrospectively analyzed the patients in terms of preoperative clinical factors including age, body mass index (BMI), estimated prostate volume, neurovascular bundle salvage, history of preoperative hormonal therapy, and MUL.

Results

The safety pad use rate was 69.6%, 86.9%, and 91.1% at 3, 6, and 12?months, respectively. On univariate and multivariate analyses, MUL were significant factors in every term of recovery of urinary continence in both groups. According to the receiver operating characteristic (ROC) curve analysis, the preoperative MUL that could best predict early recovery of urinary continence at 3 months after RALP was 12?mm.

Conclusions

We suggest that preoperative MUL >?12?mm would be a predictor of early recovery of urinary continence after RALP.
  相似文献   
137.
A multi-car elevator system is an elevator system that has more than one car installed in each elevator shaft. This system enables us to improve the transportation capability without increasing the occupied floor space. The primary purpose of this study is to consider the group control problem of operating cars efficiently without collision nor reversal in a multi-car elevator system, based on a detailed and realistic model where floor stoppage time of cars cannot be known in advance. In the context of elevator systems, reversal means that a car travels in the direction opposite to the desired direction of on-board passengers, which is prohibited because it makes passengers uncomfortable. We first propose an optimization-based collision and reversal avoidance method to operate cars in the same shaft. Next, we construct simple methods to allocate calls to individual cars under immediate and delayed guidance policies. Under the immediate guidance policy a call is allocated to a car immediately after it is registered, while under the delayed guidance policy the allocation may be changed until it is actually served. The effectiveness of the proposed group control method is examined by computer simulation.  相似文献   
138.
Additional forms of human decay-accelerating factor (DAF)   总被引:7,自引:0,他引:7  
Decay-accelerating factor (DAF) of human erythrocytes is a glycoprotein with a Mr of 65,000 that is anchored in the membrane via a glycolipid tail. During the purification of DAF, two lower m.w. forms were noted. DAF-A had an Mr of 63,000, and DAF-B had an Mr of 55,000. In a fluid phase assay, both forms accelerated the decay of the classical and the alternative C3 convertases with a specific activity similar to that of DAF. However, the decay-accelerating activity for the cell-bound C3 convertases was abolished, suggesting that neither could insert into E membranes and therefore that the glycolipid tail is altered. Analysis by molecular sieve high-pressure liquid chromatography demonstrated that DAF-A eluted with a Mr of approximately 450,000, similar to native DAF, and was thus in an aggregated form. In contrast, DAF-B eluted as a monomer with a Mr of approximately 60,000. DAF-A, but not DAF-B, bound to a hydrophobic column. To further characterize these two forms, surface-labeled human erythrocytes were incubated with phosphatidyl inositol-specific phospholipase C or papain. The phospholipase inefficiently released a form of DAF that was slightly larger (Mr of 64,000) than DAF-A. Papain efficiently released a 55,000 fragment that had the same Mr as DAF-B. To determine if DAF was cleaved by endogenous enzymes, surface-labeled erythrocytes were incubated with leukocytes. The kinetics of the leukocyte-induced degradation was similar to those observed with papain, and the released fragment aligned on seizing gels with the papain-derived fragment. We hypothesize that endogenous phospholipases and proteases cleave DAF to produce fragments similar to DAF-A and DAF-B, respectively.  相似文献   
139.
The third component of human complement, C3 is composed of two disulfide-bridged polypeptide chains of Mr 120,000 (alpha chain) and Mr 70,000 (beta chain). C3 has a thioester bond that serves as a binding site for targets when C3 is activated. Heat treatment of C3 induces autolytic peptide bond cleavage at the thioester site in the alpha chain as well as rupture of the thioester bond. The alpha chain fragments are linked to each other and beta chain via disulfide bonds. This study, however, documented that prolonged heating gave rise to liberation of several fragments including beta and the larger fragment of alpha chain. Using a fluorescent thiol reagent and [14C]iodoacetamide, we analyzed thiol residues present on each fragment, and elucidated that the thiol residue exposed by rupture of the thioester bond shifts in turn to another fragment resulting in the liberation of the fragments. The results were compatible with those on C4, and suggested that the generated thiol residue induces thiol-disulfide interchange reaction. On heating of plasma, fragments of C3 were not released, while the cleavage of the alpha chain occurred more effectively. The heated C3 (56 degrees C, 15 min) became insusceptible to C3b inactivator (I) and factor H, suggesting that additional conformational change is accompanied with cleavage of the thioester bond.  相似文献   
140.
Bisphenol A (BPA) is an endocrine disruptor that may have adverse effects on human health. We recently isolated protein-disulfide isomerase (PDI) as a BPA-binding protein from rat brain homogenates and found that BPA markedly inhibited PDI activity. To elucidate mechanisms of this inhibition, detailed structural, biophysical, and functional analyses of PDI were performed in the presence of BPA. BPA binding to PDI induced significant rearrangement of the N-terminal thioredoxin domain of PDI, resulting in more compact overall structure. This conformational change led to closure of the substrate-binding pocket in b′ domain, preventing PDI from binding to unfolded proteins. The b′ domain also plays an essential role in the interplay between PDI and ER oxidoreduclin 1α (Ero1α), a flavoenzyme responsible for reoxidation of PDI. We show that BPA inhibited Ero1α-catalyzed PDI oxidation presumably by inhibiting the interaction between the b′ domain of PDI and Ero1α; the phenol groups of BPA probably compete with a highly conserved tryptophan residue, located in the protruding β-hairpin of Ero1α, for binding to PDI. Consistently, BPA slowed down the reoxidation of PDI and caused the reduction of PDI in HeLa cells, indicating that BPA has a great impact on the redox homeostasis of PDI within cells. However, BPA had no effect on the interaction between PDI and peroxiredoxin-4 (Prx4), another PDI family oxidase, suggesting that the interaction between Prx4 and PDI is different from that of Ero1α and PDI. These results indicate that BPA, a widely distributed and potentially harmful chemical, inhibits Ero1-PDI-mediated disulfide bond formation.  相似文献   
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