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C H Tu

Publications and source records attributed to C H Tu.

8 recordsLinked to original sources

Activation of the hypothalamus characterizes the acupuncture stimulation at the analgesic point in human: a positron emission tomography study.

We performed a positron emission tomography study, using regional cerebral blood flow as the index of brain activity, to address the specificity of brain activation pattern by acupuncture stimulation of short duration at the classical analgesic point. Needling manipulation at 2 Hz was performed at a classical point of prominent analgesic efficacy (Li 4, Heku) and a near-by non-classical/non-analgesic point, respectively, in normal subjects. Regions activated by acupuncture stimulation at Li 4 included the hypothalamus with an extension to midbrain, the insula, the anterior cingulate cortex, and the cerebellum. Of note, it was only the stimulation at Li 4 that activated the hypothalamus under the similar psychophysical ratings of acupuncture sensation (deqi) as elicited by the stimulation at the two points, respectively. The data suggested that the hypothalamus might characterize the central expression of acupuncture stimulation at the classical analgesic point and serve as one key element in mediating analgesic efficacy of acupuncture stimulation.

Acupuncture Analgesia↗

Impaired cytosolic calcium mobilization and aggregation in response to collagen in platelets from Japanese black cattle with Chediak-Higashi syndrome.

OBJECTIVE: To examine whether impaired aggregation of platelets from Japanese Black cattle with Chediak-Higashi syndrome (CHS) was attributable to mobilization of cytosolic Ca2+. ANIMALS: 4 healthy Japanese Black cattle and 3 Japanese Black cattle with CHS. PROCEDURE: Aggregation and mobilization of cytosolic Ca2+ in response to various receptor agonists was measured in platelets from healthy cattle and cattle with CHS. Involvement of endogenous ADP and arachidonic acid in collagen-induced responses was examined. Cytosolic Ca2+ concentration was measured after platelets were loaded with the Ca2+ indicator fura-PE3. Platelet aggregation was measured with an aggregometer. RESULTS: Collagen (3 to 15 micrograms/ml)-induced increases in cytosolic Ca2+ concentration and aggregation were markedly impaired for platelets from cattle with CHS, compared with values for platelets from healthy cattle. Although aggregation and the sustained phase of the cytosolic Ca2+ response to ADP were also decreased in platelets from cattle with CHS, these decreases were small, compared with those in response to collagen. A cyclooxygenase inhibitor and a phospholipase A2 inhibitor did not have any effect on peak cytosolic Ca2+ concentration or collagen-induced aggregation of platelets from healthy cattle. Responses to a P2 tau-purinoceptor antagonist suggested that decreased release of endogenous ADP was only partially involved in the impaired response to collagen among platelets from cattle with CHS. CONCLUSIONS AND CLINICAL RELEVANCE: Marked inhibition of collagen-induced Ca2+ mobilization, rather than decreased release of endogenous substances, appeared to be the major cause of impaired platelet response to collagen and the hemorrhagic tendency in cattle with CHS.

Adenosine Diphosphate↗

Clinical, morphologic, and biochemical characteristics of Chediak-Higashi syndrome in fifty-six Japanese black cattle.

OBJECTIVE: To characterize Chediak-Higashi syndrome (C-HS) in Japanese Black cattle. ANIMALS: 56 of 200 cattle with a bleeding disorder and giant granules in leukocytes. PROCEDURE: Clinical observation, CBC, hemostatic screening test, platelet aggregometry, electron microscopy, platelet constituent analysis, and ophthalmoscopic examination were done. RESULTS: Affected Japanese Black cattle had increased bleeding tendency and abnormal granules in their leukocytes. Susceptibility to infection was not increased. Cutaneous albinism was evident in 6 new-born calves, but not in most affected cattle. In all affected cattle, the tapetal fundus was pale and the nontapetal fundus was almost devoid of pigment. By electron microscopy, a remarkable decrease in the number of dense granules in platelets was observed. Functionally, collagen-induced platelet aggregation was markedly reduced. CONCLUSIONS: This bleeding disorder was diagnosed as C-HS. With regard to susceptibility to infection, albinism, and mortality, clinical manifestations of C-HS in Japanese Black cattle were moderate, compared with C-HS in human beings and Hereford cattle. CLINICAL RELEVANCE: Because an autosomal recessive mode of inheritance was documented and recessive homozygotes could be easily detected, C-HS in Japanese Black cattle can be controlled.

Adenosine Diphosphate↗

Inheritance of Chediak-Higashi syndrome in Japanese black cattle.

Fifty-six Japanese black cattle affected with Chediak-Higashi syndrome (C-HS) have been referred to Miyazaki University Veterinary Teaching Hospital during the past 12 years, and 44 pedigree records were collected. In pedigree analysis, the parents had no clinical sign, the affected dams had clinically normal calves, and approximately equal numbers of males and females were affected, we therefore considered this syndrome to be an autosomal recessive trait. Quantitative genetic analyses were then made in a restricted area. Segregation analysis by the a priori method in 8 families showed that C-HS was a simple autosomal recessive trait. Furthermore, 36 dams and their 257 offspring (including 8 C-HS affected cattle) were analyzed using population genetics in the same area. The result was the same as in the former analysis.

Animals↗

[Irreducible fracture dislocation of the ankle: report of two cases].

The goal of operative treatment of ankle fracture are to obtain an anatomical reduction and rigid fixation to ensure a healed fracture and normally functioning recovery. Irreducible ankle fracture or fracture-dislocation is seldom encountered in clinical practice. Two cases of irreducible ankle fractures are presented. They are different from previous cases reported in the literature. During operation we recognized that the extensor tendons were entrapped in the distal tibiofibular joint under the extensor retinaculum. The reducible ankle fractures reported in the literature, together with the two cases in this report, are classified into three categories. Type I is a medial malleolar fracture with deltoid ligament or posterior tibialis tendon interposition. Type II is an irreducible fracture dislocation of the ankle due to posterior dislocation of the fibula. Type III is a diastatic ankle fracture with extensor tendons entrapped in the distal tibiofibular joint and restricted by extensor retinaculum. The mechanism of the irreducible ankle fracture is discussed and correlated with Lauge-Hansen classification and mechanism.

Adolescent↗