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K Chihara

Publications and source records attributed to K Chihara.

419 records · Page 24Linked to original sources

[Prolactin].

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Animals↗

Characterization of a chymotrypsin-like hydrolytic activity in the opossum kidney cell.

To characterize a chymotrypsin-like hydrolytic activity in the cell surface membranes of intact opossum kidney (OK) cells, we partially purified a protease from the membrane fractions of OK cells using Suc-Leu-Leu-Val-Tyr-MCA (Suc, succinyl; MCA, 4-methylcoumaryl-7-amide), a synthetic substrate for chymotrypsin, as the substrate. The semipure enzyme showed seryl chymotrypsin-like characteristics such as preferential hydrolysis of Suc-Leu-Leu-Val-Tyr-MCA and inhibition by phenylmethylsulfonyl fluoride, diisopropylfluorophosphate, and chymostatin. However, it clearly differed from alpha-chymotrypsin in its weak ability to hydrolyze Suc-Ala-Ala-Pro-Phe-MCA and in its high molecular mass (250-300 kDa). The enzyme also had an endopeptidase-like activity in that it cleaved human parathyroid hormone(1-84) at the Leu(37)-Gly(38) and Arg(52)-Lys(53) bonds. These results suggest that a high molecular mass chymotrypsin-like endopeptidase with unique characters is present in the membrane fractions of OK cells.

Amino Acid Sequence↗

[A case of cephalic tetanus presenting with opisthotonus].

We report a case of cephalic tetanus presenting with opisthotonus. A 49-year-old man was admitted because of repeated convulsions. The patient was a garbage truck driver known to be alcoholic, who fell down to suffer an injury of the left face two days before the onset of convulsion. Intravenous administration of diazepam and phenytoin partially relieved the convulsions. Anti-tetanus human immuno-globulin was also administered despite absence of typical clinical sign. Six hours later, however, the patient became unable to open the mouth, i.e. lockjaw developed, and the diagnosis of tetanus was made. Additional anti-tetanus human immunoglobulin of 3,000 units and 4,500 units on the next day rapidly relieved the lockjaw, convulsion, and general muscle rigidity without sequalae. The patient showed transient bilateral facial palsy and rotatory nystagmus during the course. Cephalic tetaus is characterized by a history of an injury of the head and a short latency before developing generalized tonic convulsion or opisthotonus. While a typical case presents with lockjaw, our case presented with opisthotonus, presumably because of early systemic lymphatic spreading of tetanus toxin. Early diagnosis and treatment is important to prevent generalized convulsions which are more frequent and sometimes lethal in cephalic tetanus than the common form.

Facial Injuries↗