Scanning electron microscopic study of the capillary loops in the dermal papillae. Skin of the hand of the Japanese monkey (Macaca fuscata)

The microvasculature of the skin of the hand of Japanese monkeys was examined by means of scanning electron microscopy of corrosion casts. The vasculature of all areas of the skin of the hand was examined and divided into three structures excluding the nail bed: (1) In the ball of the finger, the typical structure of the capillary loops was studied. Capillary loops were formed out of not just one capillary vessel, but two or three vessels. Each capillary vessel arose and divided into several branches at the papilla, and they became descending limbs. After the loop passed a hairpin turn, the descending limbs were 1.5 times larger than the ascending limbs in the intrapapillary portion, and they became extrapapillary venules. The descending limbs connected with the postcapillary venules in the postpapillary portion and with the horizontal network. The postcapillary venules fused with each other (1-5 loops) to form the primary and secondary venous arcades. (2) In the thenar eminence, the capillary loops were a little lower, and their grooves were wider than in the ball of the finger. The characteristic structure in this area was the interpapillar capillary network. (3) In the lateral side of the finger, the number of capillary loops formed by the arterial capillary network of the subepidermal layer was smaller. The capillary loops here had the lowest height and a simple structure.     

Role of actin in the cAMP-dependent activation of sodium/glucose cotransporter in renal epithelial cells

We examined whether actin filaments are involved in the cAMP-dependent activation of a high affinity sodium/glucose cotransporter (SGLT1) using epithelial expression systems. The expression of enhanced green fluorescent protein-tagged SGLT1 (EGFP-SGLT1) in Madin-Darby canine kidney (MDCK) cells was revealed by Western blotting and confocal laser microscopy. 8-Br-cAMP, a membrane permeable cAMP analog, enhanced [¹⁴C]-α-methyl glucopyranoside ([¹⁴C]-AMG) uptake. Both basal and 8-Br-cAMP-elicited [¹⁴C]-AMG uptakes were inhibited by N-(2{[3-(4-bromophenyl)-2-propenyl]-amino}-ethyl)-5-isoquinolinesulfonamide (H-89), a protein kinase A inhibitor, and cytochalasin D, an actin filament formation inhibitor. Furthermore, cytochalasin D inhibited the distribution of EGFP-SGLT1 at the apical surface. These results suggest that the EGFP-SGLT1 protein is functionally expressed in the apical membrane of MDCK cells, and is up-regulated by a cAMP-dependent pathway requiring intact actin filaments.     

Effects of delayed mating on preimplantation embryos in spontaneously ovulated mice

The effects of delayed mating on mouse preimplantation embryos (78 ± 1 hours) were studied by setting up different mating periods in relation to the estimated time of spontaneous ovulation. Copulation occurred even in the late morning and early afternoon after the night of spontaneous ovulation. However, females mated in the early afternoon had no viable embryos at the time of laparotomy. Although embryonic development was not affected in the groups mated 6 or 10 hours after estimated ovulation, the percentage of degenerated embryos was increased in these groups. These results suggest that prolonged intervals between the estimated time of ovulation and mating have some deleterious effects on preimplantation embryos.     

Effect of Ni2+ on Ca2+-stimulated adenosine triphosphatase in the microsomal fraction of the rat parotid gland in vitro

Ni2+ inhibited Ca2+-stimulated adenosine triphosphatase activity in the microsomal fraction of the rat parotid gland in vitro. The Ni2+ concentration required for 50% inhibition was 0.45 mM. Inhibition mechanisms of Ni2+ for Ca2+ and ATP were of the competitive type and the noncompetitive type, respectively. The Ki values of Ni2+ for Ca2+ and ATP were 0.52 and 0.59 mM, respectively. The inhibitory effect of Ni2+ was reversible.     

Characterization of β-amylase and its deficiency in various rice cultivars

 β-Amylase deficiency in various cultivars of rice was examined at the molecular level. Using an antibody against β-amylase purified from germinating seeds of rice, we were able to demonstrate the expression and organization of the β-amylase gene in normal and deficient cultivars. Although β-amylase is a starch-hydrolyzing enzyme, as is α-amylase, the β-amylase protein/gene is expressed differently from the α-amylase protein/gene; i.e. (1) β-amylase is synthesized only in aleurone cells, (2) the enzyme production in the embryo-less half-seeds is not under hormonal control. We identified some cultivars of rice that are deficient for β-amylase activity. We present new evidence that synthesis is blocked at the level of mRNA synthesis in the deficient cultivars. The usefulness of β-amylase as a crop trait is also discussed. Received: 8 May 1998 / Accepted: 5 June 1998     

Hyperthermic treatment of chromomycosis with disposable chemical pocket warmers

A case of chromomycosis in which hyperthermia proved effective is reported. The patient was a 56-year-old male bean curd maker who, without any previous history of minor trauma, developed on the extensor side of the left upper arm an eczematous lesion that underwent gradual radial expansion. The lesion showed a well-defined, 7×10 cm infiltrated erythematous plaque with the central area healed and, at the upper and lower borders, adherent scales and crusts on the surface. Histological examination revealed granulomatous changes in the dermis, as well as sclerotic cells within giant cells and microabscesses. On culturing,Fonsecaea pedrosoi was isolated. The patient was treated with disposable chemical pocket warmers, which were secured over the lesion with a rather tight elastic bandage, so that they kept the affected area warm for 24 hours a day. After a month of such hyperthermic treatment, the erythema and infiltration had decreased considerably, and microscopic examination and culture of the crusts both yielded negative results. Examination of biopsy specimens of the lesion after the third month showed that it had cicatrized. The treatment was stopped after 4 months, and no relapse occurred. We also summarize the published results of local hyperthermic treatment of chromomycosis in Japan.     

Analgesic effects of dynorphin-A and morphine in mice

To investigate whether or not dynorphin-A is analgesic, the effect of this peptide was tested in comparison with that of morphine in mice. Dynorphin-A produced a potent analgesic effect in the acetic acid writhing and tail pinch tests, but a weak effect in the tail flick test when given by intracerebroventricular injection. In contrast, morphine caused a potent analgesia in all the tests. Dynorphin-A was more effective when given by intrathecal injection than by intracerebroventricular injection, whereas morphine was equipotent by both injection routes. The results suggest that dynorphin-A is analgesic and that its analgesia may be differentiated from that of morphine.     

Nesting behavior of the semi-aquatic spider wasp,Anoplius eous,which transports its prey on the surface film of water (Hymenoptera,Pompilidae)

Anoplius eous Yasumatsu (Hymenoptera, Pompilidae) exhibits some outstanding nesting behavior. Females excavate a unicellular or multicellular nest in wet ground, or dig a single-celled nest in rotten wood, or build clustered mud cells in narrow spaces between walls of such substances as wood or vinyl sheets. The latter nest-type has been unknown within the subfamily Pompilinae. Females prepare a nest-cell before hunting, and construct it further after hunting, leaving the prey near the nest (behavior-formula: IVPTIOC). They transport their prey backward on the ground, grasping it in their mandibles by any part of the legs, and forward on the surface film of water or on the ground, grasping it by the middle part of the 1st or 2nd legs. Their only prey is the adult female semi-aquatic spider,Pardosa pseudoannulata (Lycosidae). These nesting and provisioning behavior patterns are compared with those of other pompilids. The position of the present species in the behavioral evolution of the Pompilidae is suggested.     

Solution Radioactivated by Hadron Radiation Can Increase Sister Chromatid Exchanges

When energetic particles irradiate matter, it becomes activated by nuclear reactions. Radioactivation induced cellular effects are not clearly understood, but it could be a part of bystander effects. This investigation is aimed at understanding the biological effects from radioactivation in solution induced by hadron radiation. Water or phosphate buffered saline was activated by being exposed to hadron radiation including protons, carbon- and iron-ions. 1 mL of radioactivated solution was transferred to flasks with Chinese hamster ovary (CHO) cells cultured in 5 mL of complete media. The induction of sister chromatid exchanges (SCE) was used to observe any increase in DNA damage responses. The energy spectrum and the half-lives of the radioactivation were analyzed by NaI scintillation detector in order to identify generated radionuclides. In the radioactivated solution, 511 keV gamma-rays were observed, and their half-lives were approximately 2 min, 10 min, and 20 min. They respectively correspond to the beta+ decay of ¹⁵O, ¹³N, and ¹¹C. The SCE frequencies in CHO cells increased depending on the amount of radioactivation in the solution. These were suppressed with a 2-hour delayed solution transfer or pretreatment with dimethyl sulfoxide (DMSO). Our results suggest that the SCE induction by radioactivated solution was mediated by free radicals produced by the annihilated gamma-rays. Since the SCE induction and DMSO modulation are also reported in radiation-induced bystander effects, our results imply that radioactivation of the solution may have some contribution to the bystander effects from hadron radiation. Further investigations are required to assess if radioactivation effects would attribute an additional level of cancer risk of the hadron radiation therapy itself.