1.Effects of cadmiumin vitro on contractile and relaxant responses of isolated rat aortas.
Yuji TAKAHASHI ; Michael POTESER ; Hidehisa MASUI ; Naoko KOIZUMI ; Ichiro WAKABAYASHI
Environmental Health and Preventive Medicine 2004;9(6):251-256
OBJECTIVECadmium is known to affect the vascular tone of isolated blood vesselsin vitro and the arterial pressure of ratsin vivo. However, the mechanisms of cadmium actions on the vascular system have not been clarified. To elucidate the actions of cadmium on vascular tonus, effects of cadmium on vasocontractile and vasorelaxant responsesin vitro were investigated using aortic strips isolated from rats.
METHODSAortic strips isolated from male Wistar rats were incubated with CdCl(2) (10μM) for 24 hr, washed with fresh CdCl(2)-free medium, and then used for measurement of isometric tension and Western blot analysis of eNOS (endothelial nitric oxide synthase) and iNOS (inducible nitric oxide synthase).
RESULTSIn the aortas pretreated with cadmiumin vitro, the contractile response to phenylephrine was significantly higher than that in the control aortic strips pretreated with a vehicle. The sodium nitroprusside-induced relaxing response was significantly higher in the aortic strips pretreated with cadmium for 24 hr, compared with that in the control pretreated with a vehicle. The isoproterenol-induced relaxing response was also significantly higher in the cadmium-accumulated aortic strips.In vitro cadmium treatment slightly but not significantly increased the acetylcholine-induced relaxation of the aortic strips. Cadmium treatment induced expression of iNOS and significantly increased expression of eNOS in the aortic strips, while it did not affect expression of β-actin.
CONCLUSIONSCadmium treatmentin vitro augmented the α1 adrenoceptor-mediated contractile response, even though eNOS and iNOS were upregulated by cadmium treatment. NO-induced and β-adrenoceptor-mediated relaxing responses were also augmented by cadmium treatment. These results suggest that both vasocontractile and vasorelaxing responses are augmented in cadmium-accumulated aortas.
2.Clinical features of catheter-related candidemia at disease onset.
Yusuke YOSHINO ; Yoshitaka WAKABAYASHI ; Satoshi SUZUKI ; Kazunori SEO ; Ichiro KOGA ; Takatoshi KITAZAWA ; Shu OKUGAWA ; Yasuo OTA
Singapore medical journal 2014;55(11):579-582
INTRODUCTIONEarly detection of catheter-related candidemia is necessary to ensure that patients receive prompt and appropriate treatment. The aim of the present case-control study is to investigate the clinical features of catheter-related candidemia at disease onset, so as to determine the clinical indications for empiric antifungal therapy.
METHODSAll 41 cases of catheter-related candidemia from September 2009 to August 2011 at a teaching hospital were included in the present study. To determine the characteristics that were risk factors for developing catheter-related candidemia, we compared all cases of catheter-related candidemia with all 107 cases of catheter-related blood stream infection (CRBSI) caused by non-Candida spp.
RESULTSIn comparison with CRBSI due to non-Candida spp., the duration of catheter use was significantly longer in cases of catheter-related candidemia (13.9 ± 9.0 days vs. 23.2 ± 25.2 days). There was also a significant difference in the frequency of pre-antibiotic treatment between catheter-related candidemia and CRBSI due to non-Candida spp. (97.6% [40/41 cases] vs. 44.9% [48/107 cases]). Patients with catheter-related candidemia also had significantly more severe clinical statuses (measured using the Sepsis-related Organ Failure Assessment score) than patients with CRBSI due to non-Candida spp. (7.63 ± 3.65 vs. 5.92 ± 2.81).
CONCLUSIONWhen compared to patients with CRBSI caused by non-Candida spp., patients with catheter-related candidemia had significantly more severe clinical backgrounds, longer duration of catheter use and more frequent prior administration of antibiotic agents.
Aged ; Aged, 80 and over ; Candida ; pathogenicity ; Candidemia ; diagnosis ; Case-Control Studies ; Catheter-Related Infections ; diagnosis ; Female ; Humans ; Male ; Middle Aged
3.Resveratrol inhibits Ca
Mikio MARUMO ; Kazumi EKAWA ; Ichiro WAKABAYASHI
Environmental Health and Preventive Medicine 2020;25(1):70-70
BACKGROUND:
Resveratrol has been shown to inhibit platelet aggregation. However, the mechanism for this action of resveratrol remains to be clarified. The purpose of this study was to elucidate the Ca
METHODS:
Ca
RESULTS:
Thapsigargin-induced Ca
CONCLUSIONS
The results suggest that resveratrol inhibits thrombin-induced platelet aggregation through decreasing Ca
Antioxidants/administration & dosage*
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Calcium/physiology*
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Humans
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Platelet Aggregation/drug effects*
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Platelet Aggregation Inhibitors/pharmacology*
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Resveratrol/pharmacology*
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Signal Transduction/drug effects*