Thoracic duct cyst in supraclavicular region.

A 28-year-old female attended an outpatient clinic in October, 1989, because of a tumor in the left supraclavicular fossa, detected in a health examination. Following exploratory puncture of the tumor which yielded milky-white fluid, suggesting a cyst in the thoracic duct, she was admitted to our department. The cyst was unilocular measuring about 6 cm in diameter, and the fluid content was chyle-rich in lipids. Lymphography demonstrated a lymphatic structure adjacent to the lesion and scattered lymph vessels on the cyst surface. On November 16 the cyst was resected. A restiform structure was observed between the cyst and the thoracic duct, but the presence or absence of communication was unclear. The histological diagnosis was thoracic duct cyst. Thoracic duct cyst occurring in the cervical region is very rare. Our case may provide useful information as to its pathogenesis and the mode of retention of cyst fluid.     

Epidural opioids for postoperative pain relief following hepatectomy.

Postoperative pain relief with epidural morphine or buprenorphine and intramuscular morphine was investigated in 67 patients undergoing hepatectomy. When the patient first complained of pain after surgery, 1 or 2mg of epidural morphine, or 0.06 mg of epidural buprenorphine given either at T 10-11 or L 3-4, or 0.1 mg/kg of morphine intramuscularly was administered. Lumbar epidural morphine 2mg, as well as thoracic epidural morphine 2mg, produced excellent and long-lasting pain relief. Nine of 12 patients receiving thoracic epidural buprenorphine 0.06 mg were completely pain-free. Thoracic epidural morphine 1 mg and lumbar epidural buprenorphine 0.06 mg produced incomplete analgesia. Analgesic duration of intramuscular morphine tended to be shorter than that of 2 mg of epidural morphine. PaCO2 increased significantly following thoracic epidural morphine 2 mg, although PaCO2 did not change after lumbar epidural morphine 2 mg. No patient had serious side effects. The lumbar epidural administration of 2 mg morphine may be recommended for postoperative analgesia following hepatectomy.     

Difference between substance P- and acetylcholine-induced currents in mammalian smooth muscle cells.

The effects of substance P (SP) and acetylcholine (ACh) on membrane currents were compared using freshly isolated smooth muscle cells from guinea-pig ileum. Both SP (100 nM) and ACh (10 microM) induced inward currents at negative holding potentials. The ACh-induced current, but not the SP-induced current, showed relaxation upon voltage-stepping. The SP-induced current was increased by hyperpolarization more negative than -50 mV whereas the ACh-induced current was decreased by hyperpolarization. The results suggest that the SP-induced inward current is elicited via an ionic pathway different from that involved with ACh-activated channels.     

Effects of arginine derivatives on soluble guanylate cyclase from neuroblastoma N1E 115 cells

The effects of L-arginine (Arg) derivatives on soluble guanylate cyclase from neuroblastoma N1E 115 cells were examined. The Arg derivatives were modified at the -NH2, -COOH, C alpha-proton or guanidino group of Arg. Among the synthesized derivatives, eight compounds, i.e. the 5-(dimethylamino)-1-naphthalenesulfonyl (DNS) ones, especially N-cyclohexyl-2-(N-DNSamino)-5-guanidino-2-methylvaleramide and 1-[2-(N-DNSamino)-2-(2-imino-1,2,3,4,5,6-hexahydropyrimidin- 4-yl)acetyl]- piperidine, were found to inhibit the activity of crude guanylate cyclase in the 105,000 g supernatant fraction of the cell homogenate. The enzyme, partially purified by a column of Chelex 100 Na+, was also inhibited by these eight compounds. The mode of the inhibition was competitive. The Ki values were in the range of 2-8 microM for the enzyme in the 105,000 g supernatant fraction and 3-16 microM for the partially purified enzyme, in the presence of Mg2+ as a metal cofactor. In contrast, a new derivative, methyl 2-amino-5-guanidinovalerate (M Arg ME), as well as the Arg methyl ester (Arg ME) and Arg; were found to enhance the activity of the partially purified guanylate cyclase; KA values of M Arg ME, Arg ME and Arg were approximately 9, 4 and 3 microM respectively. From these results, the free guanidino group including 2-imino-1,2,3,4,5,6-hexahydropyrimidin-4-yl or 2-imino-1,2,3,4,5,6-hexahydropyrimidin-5-yl and modification of the --NH2 residue with a hydrophobic group such as DNS seemed to be essential for inhibition of the guanylate cyclase; however, the guanidino and --NH2 residue of Arg should be free for activation by these Arg derivatives.     

Different origin of leiomyoblastoma by immunohistochemical study.

Leiomyoblastoma has been regarded as a neoplasm of smooth muscle origin. With recent progress in immunohistostaining techniques, many clinicopathological discrepancies have been pointed out about the origin of leiomyoblastoma. It has been claimed that gastrointestinal non-epithelial tumors should be regarded as stromal tumors in order to study their origin. In the present study, we performed various forms of immunohistostaining in seven cases of leiomyoblastoma to determine their origin. One case expressed desmine and muscle specific actin and was considered to be derived from smooth muscle. Four neoplasms expressed X-100 protein (two cases were also NSE positive) and were thought to be derived from the nerve. Two cases were of unknown derivation. These results suggest that the cells of leiomyoblastoma may arise from a primitive to totipotential cell of neural lineages that may anomalously express smooth muscle filaments.