Fraction of pluripotent hemopoietic stem cells in DNA synthesis varies with generation age

The fraction of pluripotent hemopoietic stem cell (CFU-S) in DNA synthesis (S phase) was evaluated for day 7 through 13-spleen colonies. The CFU-S in S phase in normal bone marrow decreased progressively, from 43% on day 7, to 23% on day 11, and 4% on day 13. The cycling fraction of 5-fluorouracil (5FU)-treated CFU-S was also evaluated. The S phase fraction for CFU-S surviving 5FU was 100.0, 58.8, 54.7, and 25.6% at day 7, 9, 11, and 13, respectively, and the proportion of the fraction also was not constant. The S phase fraction for CFU-S surviving 5FU was much higher than that for normal bone marrow cells; this might be attributed to the extensive regenerating ability of CFU-S surviving 5-FU. The results obtained suggest that a stem cell population in S-phase may exhibit a hierarchy based on the "generation-age hypothesis" (Rosendaal, Hodgson, and Bradley 1979) of the stem cell compartment.     

Enkephalin-like immunoreactive neurons and fibers in the ventromedial hypothalamic nucleus

Enkephalin-like immunoreactive (ENK-IR) neurons and fibers in the rat ventromedial hypothalamic nucleus (VMH) were examined by light and electron microscopy using the peroxidase-antiperoxidase immunocytochemistry. There were groups of ENK-IR neurons present in the ventrolateral part of the VMH, and such neurons were scattered elsewhere. These neurons had perikarya 10-25 microns in diameter with moderately developed cell organelles and enfolded nuclei that were often distributed eccentrically placed in the cell. The perikarya and dendrites contained diffuse, large-cored vesicles (LCV) (60-230 nm with a predominance in the 60-80 nm). ENK-IR neurons received synaptic inputs on the soma and dendrites from unlabeled axonal boutons containing many small, clear vesicles and occasional LCV. The ultrastructural features of the ENK-IR cells in the VMH seemed to correspond to the "common cells" described by Millhouse. Dense ENK-IR fibers were distributed in this nucleus throughout the rostrocaudal and ventrodorsal areas. Axonal boutons containing numerous small, clear vesicles, and dispersed LCV generally made synaptic contacts with the cell bodies and dendrites of unlabeled neurons. The findings suggest that opioid peptides directly influence VMH neurons through synaptic contacts.     

Effects of Chinese herbal medicine "kanbaku-taiso-to" on transmembrane ionic currents and its local anesthetic action

The Chinese herbal medicine, "Kanbaku-taiso-to" (KT) which is a mixture of Glycyrrhizae Radix, Triticii Semen and Zizyphi Fructus, sometimes shows marked effects on insomnia, infantile convulsions and emotional irritability. To elucidate the mechanism of the sedative effect of KT, effects of KT on the transmembrane ionic currents and local anesthetic action were examined and the following results were obtained. KT showed an inhibition of sodium, calcium and potassium currents in snail neurons. KT showed an inhibitory effect on pentylenetetrazol-induced bursting activity. KT had local anesthetic action on frog nerve fibers. Together with our previous study, these results suggest that KT has an inhibitory effect on hyperexcitability of the neuronal membrane and this is the main cause of the sedative effect of KT.     

A Pilon Fracture With Fibular Head Dislocation Treated With the Use of 3D Preoperative Planning: A Case Report and Literature Review

Pilon fractures with intact fibula have been associated with low-energy trauma. However, the compression force onto the ankle joint can damage the tibiofibular linkage as in a Maisonneuve fracture. Herein, we describe a case of a patient who had a pilon fracture (AO type 43 C3.2) without a fibular fracture. Three-dimensional preoperative simulation by reduction with the surface registration technique was performed as the fibular length was intact and there was no reference for the tibial length. The preoperative simulation revealed superior fibular head dislocation and shortening of the distal tibia. After emergency external fixation on the day of arrival, a 2-staged surgery was performed. During the first operation, the fibular head was reduced and the tibial posterolateral fragment was fixed to restore the tibia length. During the second operation, medial and anterolateral fragments were fixed in order to reduce joint surface of the distal tibia. In general, proximal fibular head fractures are easily overlooked. In the case of pilon fractures with severe length shortening of the tibia without a fibular fracture, a proximal tibiofibular injury should be suspected.     

VAMP2 is expressed in myogenic cells during rat development

Vesicle-associated membrane protein 2 (VAMP2) is a member of the SNARE family of proteins that regulate the intracellular vesicle fusion process. This study investigated the developmental expression of VAMP2 in the rat embryo. In the trunk, VAMP2 was primarily found in the heart on embryonic day (E) 10. On E12.5, VAMP2 expression was found in nerve fibers, somites, and heart. In somites, epithelial cells in the dorsomedial lip, and elongated myoblasts in myotome were positive for VAMP2. On E16.5, VAMP2 was expressed in the heart, nerve fibers, and skeletal muscles. In skeletal muscles, multinuclear myotubes were positive for VAMP2. In the head, where muscles are derived both from somitic and non-somitic origin, VAMP2 was found in myotubes of the extrinsic ocular muscles and masseter muscle on E16.5. These findings suggest the involvement of VAMP2 in the development of skeletal muscles of somitic and non-somitic origins.     

Vasculitis and Pyrexia Associated with Superficial Spreading Gastric Carcinoma

A case of low grade fever developing about a month before the discovery of gastric carcinoma is reported. No findings of infection or collagen disease were revealed. The fever continued for about 3 months, but promptly disappeared after surgical removal of the tumor. A superficial spreading mucosal carcinoma with minimal invasion to the sub-mucosa was seen in the antrum, showing the features of poorly differentiated adenocarcinoma. In addition, unique venous inflammation was recognized beneath and around the neoplasm. Arteries and lymph vessels did not exhibit any inflammatory changes. It was presumed that the gastric carcinoma had induced phlebitis, which subsequently brought about the fever. As to the pathogenetic mechanism, it was suggested that a substance produced by the carcinoma cells flowed into nearby veins to induce the phlebitis. Acta Pathol Jpn 42 : 293-297, 1992.     

Purification of a Protective Antigen from a Saline Extract of Pasteurella multocida

It has been shown previously that soluble material extracted from Pasteurella multocida P-1059 by a 2.5% NaCl solution protects turkeys from generalized septicemia at a subsequent challenge exposure to the organism. In the present study, a protective antigen was purified from the crude soluble material by chromatographic methods. Four protein peaks were obtained by gel filtration with Sephadex G-200. The protective antigen was detected only in the first peak fraction, which contained a substantial amount of carbohydrate. The peak 1 fraction was adsorbed onto DEAE-cellulose and eluted by a linear gradient of NaCl. Fractions corresponding to a single protein peak were pooled and passed through an immunoadsorbent column to remove any possible serum component originating from the growth medium. The purified antigen had a carbohydrate/protein ratio of 1.5 and formed a single precipitin line with rabbit antiserum against the crude material in gel diffusion and immunoelectrophoresis analyses. The antigen produced antibodies in rabbits and turkeys which formed a single precipitin line against the crude material. Upon sodium dodecyl sulfate-polyacryl-amide gel electrophoresis, the purified antigen showed three protein bands, corresponding to molecular weights of 44,000, 31,000, and 25,000, and one carbohydrate band. The carbohydrate band did not correspond to any of the three protein bands. Upon isoelectric focusing gel analysis, the purified antigen showed two bands (pI = 3.5 to 4.0 and 4.5 to 5.5), but the two bands were antigenically identical by isoelectric focusing crossed immunoelectrophoresis. The 50% protective dose of the purified antigen was between 10 and 50 μg of protein in trials where two doses were given at 14-day intervals to 10- to 20-week-old turkeys.