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31.

Objective

We devised a percutaneous coronary intervention (PCI) scoring system based on angiographic lesion complexity and assessed its association with in-hospital complications.

Background

Although PCI is finding increasing application in patients with coronary artery disease, lesion complexity can lead to in-hospital complications.

Methods

Data from 3692 PCI patients were scored based on lesion complexity, defined by bifurcation, chronic total occlusion, type C, and left main lesion, along with acute thrombus in the presence of ST-segment elevation myocardial infarction (1 point assigned for each variable).

Results

The patients’ mean age was 67.5 +/- 10.8 years; 79.8% were male. About half of the patients (50.3%) presented with an acute coronary syndrome, and 2218 (60.1%) underwent PCI for at least one complex lesion. The patients in the higher-risk score groups were older (p < 0.001) and had present or previous heart failure (p = 0.02 and p = 0.01, respectively). Higher-risk score groups had significantly higher in-hospital event rates for death, heart failure, and cardiogenic shock (from 0 to 4 risk score; 1.7%, 4.5%, 6.3%, 7.1%, 40%, p < 0.001); bleeding with a hemoglobin decrease of >3.0 g/dL (3.1%, 11.0%, 13.1%, 10.3%, 28.6%, p < 0.001); and postoperative myocardial infarction (1.5%, 3.1%, 3.8%, 3.8%, 10%, p = 0.004), respectively. The association with adverse outcomes persisted after adjustment for known clinical predictors (odds ratio 1.72, p < 0.001).

Conclusion

The complexity score was cumulatively associated with in-hospital mortality and complication rate and could be used for event prediction in PCI patients.  相似文献   
32.
Katakori is a symptom name that is unique to Japan, and refers to myofascial pain syndrome-like clinical signs in the shoulder girdle. Various methods of pain relief for katakori have been reported, but in the present study, we examined the clinical effects of multi-acupuncture point injections (MAPI) in the acupuncture points with which we empirically achieved an effect, as well as the anatomical sites affected by liquid medicine. The subjects were idiopathic katakori patients (n = 9), and three cadavers for anatomical investigation. BL-10, GB-21, LI-16, SI-14, and BL-38 as the WHO notation were selected as the acupuncture point. Injections of 1 mL of 1% w/v mepivacaine were introduced at the same time into each of these points in the patients. Assessment items were the Pain Relief Score and the therapeutic effect period. Dissections were centered at the puncture sites of cadavers. India ink was similarly injected into each point, and each site that was darkly-stained with India ink was evaluated. Katakori pain in the present study was significantly reduced by MAPI. Regardless of the presence or absence of trigger points, pain was significantly reduced in these cases. Dark staining with India ink at each of the points in the anatomical analysis was as follows: BL-10: over the rectus capitis posterior minor muscle and rectus capitis posterior major muscle fascia; GB-21: over the supraspinatus muscle fascia; LI-16: over the supraspinatus muscle fascia; SI-14: over the rhomboid muscle fascia; and BL-38: over the rhomboid muscle fascia. The anatomical study suggested that the drug effect was exerted on the muscles above and below the muscle fascia, as well as the peripheral nerves because the points of action in acupuncture were darkly-stained in the spaces between the muscle and the muscle fascia.  相似文献   
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34.
We examined factors controlling temporal changes in net ecosystem production (NEP) in a high Arctic polar semi-desert ecosystem in the snow-free season. We examined the relationships between NEP and biotic and abiotic factors in a dominant plant community (Salix polaris–moss) in the Norwegian high Arctic. Just after snowmelt in early July, the ecosystem released CO2 into the atmosphere. A few days after snowmelt, however, the ecosystem became a CO2 sink as the leaves of S. polaris developed. Diurnal changes in NEP mirrored changes in light incidence (photosynthetic photon flux density, PPFD) in summer. NEP was significantly correlated with PPFD when S. polaris had fully developed leaves, i.e., high photosynthetic activity. In autumn, NEP values decreased as S. polaris underwent senescence. During this time, CO2 was sometimes released into the atmosphere. In wet conditions, moss made a larger contribution to NEP. In fact, the water content of the moss regulated NEP during autumn. Our results indicate that the main factors controlling NEP in summer are coverage and growth of S. polaris, PPFD, and precipitation. In autumn, the main factor controlling NEP is moss water content.  相似文献   
35.
Megalin-mediated endocytosis of cystatin C in proximal tubule cells   总被引:1,自引:0,他引:1  
Serum levels of cystatin C, an endogenous cysteine proteinase inhibitor, are often used as an indicator of glomerular filtration rate. Although it is known that cystatin C is filtered by glomeruli and metabolized in proximal tubule cells (PTC), the precise molecular mechanism underlying this process is undetermined. Using quartz-crystal microbalance analyses, we demonstrate that cystatin C binds directly to megalin, an endocytic receptor in PTC, in a Ca(+)-dependent manner. We also find that cystatin C is endocytosed specifically via megalin in rat yolk sac epithelium-derived L2 cells which share a variety of characteristics with PTC. Finally, in vivo studies using kidney-specific megalin knockout mice provide evidence that megalin mediates proximal tubular uptake of cystatin C. We conclude that megalin is an endocytic receptor of cystatin C in PTC.  相似文献   
36.
(R)-Specific enoyl-coenzyme A (enoyl-CoA) hydratases (PhaJs) are capable of supplying monomers from fatty acid β-oxidation to polyhydroxyalkanoate (PHA) biosynthesis. PhaJ1Pp from Pseudomonas putida showed broader substrate specificity than did PhaJ1Pa from Pseudomonas aeruginosa, despite sharing 67% amino acid sequence identity. In this study, the substrate specificity characteristics of two Pseudomonas PhaJ1 enzymes were investigated by site-directed mutagenesis, chimeragenesis, X-ray crystallographic analysis, and homology modeling. In PhaJ1Pp, the replacement of valine with isoleucine at position 72 resulted in an increased preference for enoyl-coenzyme A (CoA) elements with shorter chain lengths. Conversely, at the same position in PhaJ1Pa, the replacement of isoleucine with valine resulted in an increased preference for enoyl-CoAs with longer chain lengths. These changes suggest a narrowing and broadening in the substrate specificity range of the PhaJ1Pp and PhaJ1Pa mutants, respectively. However, the substrate specificity remains broader in PhaJ1Pp than in PhaJ1Pa. Additionally, three chimeric PhaJ1 enzymes, composed from PhaJ1Pp and PhaJ1Pa, all showed significant hydratase activity, and their substrate preferences were within the range exhibited by the parental PhaJ1 enzymes. The crystal structure of PhaJ1Pa was determined at a resolution of 1.7 Å, and subsequent homology modeling of PhaJ1Pp revealed that in the acyl-chain binding pocket, the amino acid at position 72 was the only difference between the two structures. These results indicate that the chain-length specificity of PhaJ1 is determined mainly by the bulkiness of the amino acid residue at position 72, but that other factors, such as structural fluctuations, also affect specificity.  相似文献   
37.
The larvicidal activity against Culex pipiens of all stereoisomers of dihydroguaiaretic acid (DGA) and secoisolariciresinol was measured, and these DGAs were found to be potent. Sixteen (-)-DGA derivatives were then newly synthesized to analyze their structure-activity relationship. Two derivatives monohydroxylated at the 3- or 4-position of the 7-phenyl group of DGA induced acute paralytic activity in the mosquitoes. Derivatives with several hydroxyl groups had lower activity than the natural compound, suggesting that hydrophobicity was probably an important factor for their insecticidal activity.  相似文献   
38.
39.
The designed cytosine-carbohydrate hybrid molecule selectively recognized and stabilized the bulged duplex DNA possessing the complementary bulged DNA base, guanine, while the nucleotide base itself did not exhibit any such ability. It was also found that the assistance of the carbohydrate to stabilize the interaction between the nucleotide base and the complementally bulge DNA base is very helpful for the selective recognition and stabilization of the single-bulged duplex DNA.  相似文献   
40.
Monascin (1) constitutes one of the azaphilonoid pigments in the extracts of Monascus pilosus-fermented rice (red-mold rice). Compound 1 was evaluated for its anti-tumor-initiating activity via oral administration on the two-stage carcinogenesis of mouse skin tumor induced by peroxynitrite (ONOO-; PN) or by ultraviolet light B (UVB) as an initiator and 12-O-tetradecanoylphorbol-13-acetate (TPA) as a promoter. Compound 1 exhibited marked inhibitory activity on both PN- and UVB-induced mouse skin carcinogenesis tests. These findings suggest that compound 1 may be valuable as potential cancer chemopreventive agent in chemical and environmental carcinogenesis.  相似文献   
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