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Y Fukuuchi

Publications and source records attributed to Y Fukuuchi.

197 records · Page 11Linked to original sources

Quantitative measurement of blood flow velocity in feline pial arteries during hemorrhagic hypotension and hypercapnia.

Due to methodologic difficulties, few investigations have been made on the blood flow velocity in the cerebral microcirculation. Using a newly developed video camera method, we simultaneously measured the blood flow velocity and diameter of pial arteries during hemorrhagic hypotension, after blood pressure recovery, and during CO2 inhalation in cats. When the mean arterial blood pressure was lowered from 129.7 +/- 6.6 to 71.5 +/- 4.1 mm Hg, the blood flow velocity inevitably decreased from 36.6 +/- 5.3 to 27.0 +/- 3.9 mm/sec (p less than 0.001). The calculated blood flow rate [pi X (diameter/2)2 X flow velocity] was preserved in cases with concomitant vasodilation. Conversely, the blood flow velocity increased from 25.3 +/- 5.1 to 31.0 +/- 5.4 mm/sec (p less than 0.001) after mean arterial blood pressure recovery from 67.1 +/- 3.7 to 129.8 +/- 5.8 mm Hg. The blood flow rate was again preserved in vessels with a vasoconstrictive response. Each pial artery apparently dilated or constricted in proportion to the decrease or increase in flow velocity during blood pressure changes, maintaining a constant cerebral blood flow. This indicated the importance of the pial arteries in the mechanisms of cerebral blood flow autoregulation. During 5% CO2 inhalation, the blood flow velocity increased markedly from 25.4 +/- 4.6 to 37.2 +/- 10.0 mm/sec (p less than 0.05), while the pial artery diameter (85.0 +/- 13.7 microns) increased by 9.6 +/- 1.5% (p less than 0.01). The increased flow velocity might be attributable to preferential dilatation of small arterioles or intraparenchymal vessels during hypercapnia.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Expression of interleukin-6 in cerebral neurons and ovarian cancer tissue in Trousseau syndrome.

Interleukin-6 (IL-6) is reportedly increased in serum and CSF from acute stroke patients. However, the cellular origin and possible role of IL-6 in CNS after stroke are unclear. We describe a woman with recurrent stroke, disseminated intravascular coagulation (DIC) and non-bacterial thrombotic endocarditis (NBTE) caused by ovarian cancer (Trousseau syndrome). The patient died 50 days after the final episode of cerebral embolism. The immunohistochemical study revealed IL-6 protein to have been expressed both in cerebral neurons spared from ischemic insult and in epithelial cells of the ovarian tumor. We speculate that IL-6 produced in ovarian cancer may be associated with the hypercoagulable state and the development of NBTE in this patient. In contrast, IL-6 induction in cerebral neurons may contribute to the survival of these neurons after a stroke.

Coronary Thrombosis↗