Unique tissue distribution of a mouse macrophage C-type lectin

We examined mouse tissue for the expression of macrophage galactose/N-acetylgalactosamine-specificC-type lectin using a rat monoclonal antibody (mAb) specificfor this lectin (mAb LOM-14). The binding of mAb LOM-14 wasdetected in detergent extracts from tissue by means of immunoblottinganalysis. It was shown that this mAb did not cross-react withmouse hepatic lectins, a structural homologue. The macrophagelectin was widely distributed among various mouse tissues asjudged by the affinity isolation followed by the immunochemicaldetection. The exceptions were brain, liver, kidney, small intestine,and peripheral blood. Extracts from these organs exhibited,at best, very weak signals upon mAb LOM-14 binding, despitethe presence of cells expressing macrophage markers. The mostintense signal was observed in the extract from skin, suggestingthat cells expressing this lectin are abundant in skin. Thetissues shown to contain this lectin were further investigatedby immunohistochemical staining of the sections. Cells weredistributed in the connective tissue and in the interstice,particularly the dermis and subcutaneous layer of skin. Cellslocalized in the epithelium of skin (epidermis) or other epitheliathat we examined were not stained. Perivascular localizationof cells stained with mAb LOM-14 was also demonstrated in cardiacand skeletal muscle tissues. Immunoelectron microscopy revealedthe presence of this lectin along the rough endoplasmic reticulum.In conclusion, the distribution of C-type lectin specific forgalactose/N-acetylgalactosamine in mice was unique. The connectivetissue-specific distribution should provide important informationon the biological role of this lectin. lectin macrophage calcium-type lectin connective tissue     

Physical effects of negative air ions in a wet sauna

 The physical effects of negative air ions on humans were determined in an experimental sauna room equipped with an ionizer. Thirteen healthy persons took a wet sauna bath (dry bulb temperature 42° C, relative humidity 100%, 10 min exposure) with or without negative air ions. The subjects were not told when they were being exposed to negative air ions. There were no differences in the moods of these persons or changes in their blood pressures between the two saunas. The surface temperatures of the foreheads, hands, and legs in the sauna with negative ions were significantly higher than those in the sauna without ions. The pulse rates and sweat produced in the sauna with ions were singificantly higher than those in the sauna without ions. The results suggest that negative ions may amplify the effects on humans of the sauna. Received: 31 March 1995 / Revised: 25 July 1995 / Accepted: 26 July 1996     

Effect of Temperature on Pratylenchus penetrans Development

Reproduction and development of Pratylenchus penetrans were studied on genetically transformed ladino clover roots. Solitary females developing on transformed roots in nutrient gellan gum medium (pH 5.5) deposited 1.2, 1.5, 1.6, 1.8, and 2.0 eggs per day at the respective temperatures of 17, 20, 25, 27, and 30 °C. The number of eggs deposited was highly correlated with temperature. A reduction in egg-laying rates at the start of hatching was observed at all temperatures. Juvenile mortality was higher at 17 °C (50.4%), 20 °C (50.3%), and 30 °C (58.4%) than at 25 °C (34.6%) and 27 °C (37.6%). Life-cycle (egg deposition to egg deposition) duration was 46, 38, 28, 26, and 22 days at the respective temperatures. The developmental zero degrees (°C) and the effective accumulative temperatures (degree-days) required for hatching, female emergence, and onset of oviposition (completion of one generation) of P. penetrans were estimated to be 2.7 and 200, 4.2 and 548, and 5.1 and 564, respectively. Pratylenchus penetrans reproduces over a wide range of temperatures.     

Nanomolar Amyloid β Protein-Induced Inhibition of Cellular Redox Activity in Cultured Astrocytes

Abstract: It has been previously reported that Alzheimer's amyloid β protein (Aβ) induces reactive astrocytosis in culture. In the present study, we found that Aβ potently inhibits cellular redox activity of cultured astrocytes, as determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide reduction assay. The following comparative studies revealed several differences between these two actions of Aβ on astrocytes. First, Aβ-induced reactive morphological change was suppressed by the presence of serum or thrombin, and Aβ inhibition of cellular redox activity was observed in either the presence or the absence of serum. Second, micromolar concentrations (10 µ M or more) were required for Aβ to induce reactive astrocytosis, whereas nanomolar concentrations (0.1–100 n M ) were sufficient to inhibit cellular redox activity. Third, the effect of micromolar Aβ was virtually irreversible, but nanomolar Aβ-induced inhibition of cellular redox activity was reversed by washing out Aβ. Furthermore, as it has been reported that Aβ neurotoxicity is mediated by reactive oxygen species, we also examined if similar mechanisms are involved in astrocytic response to Aβ. However, neither Aβ-induced morphological change nor inhibition of redox activity was blocked by antioxidants, suggesting that these effects are not caused by oxidative stress.     

Protective Effects of Pyridoxal Phosphate Against Glucose Deprivation-Induced Damage in Cultured Hippocampal Neurons

Abstract: When hippocampal cultures were deprived of glucose, massive release of lactate dehydrogenase (LDH), an indicator of neuronal death, occurred via NMDA receptor activation. Addition of pyridoxal phosphate (PLP; 1 and 10 µ M ) inhibited this LDH release in a concentration-dependent manner. Prior exposure to PLP evoked more potent inhibitory effects on LDH release compared with those treated at the onset of glucose deprivation. Furthermore, PLP inhibited the reduction of intracellular content of pyruvate induced by glucose deprivation, which was accompanied by the reversal of intracellular ATP depletion. A noteworthy elevation of extracellular glutamate in response to glucose deprivation was completely reversed by addition of PLP. Aminooxyacetic acid, a potent inhibitor of PLP-dependent enzymes, antagonized the effects of PLP on LDH release, pyruvate production, and ATP formation. These results suggest that PLP protects neurons from glucose deprivation-induced damage by enhancing the formation of energy-yielding products and relieving extracellular load of glutamate. The observed phenomena further indicate that PLP might be used prophylactically against neuronal death induced by metabolic disorders.     

p53-Knockout Mice Are Protected Against the Long-Term Effects of Methamphetamine on Dopaminergic Terminals and Cell Bodies

Abstract: p53-knockout mice provide a useful model to test the role of p53 in the neurotoxic effects of drugs in vivo. To test the involvement of p53 in methamphetamine (METH)-induced toxicity, wild-type mice, as well as heterozygous and homozygous p53-knockout male mice, were administered four injections of three different doses (2.5, 5.0, and 10.0 mg/kg) of the drug given at 2-h intervals within the space of 1 day. METH caused a marked dose-dependent loss of dopamine transporters in both the striatum and the nucleus accumbens of wild-type mice killed 2 weeks after drug administration. However, this METH-induced decrease in dopamine transporters was attenuated in both homozygous and heterozygous p53-knockout mice, with homozygous animals showing significantly greater protection. The possibility for p53 involvement in METH-induced toxicity was also supported by the observation that METH caused marked increases in p53-like immunoreactivity in the striata of wild-type mice and very little change in heterozygous p53-knockout mice, whereas no p53-like immunostaining was detected in the homozygous p53-knockout mice. Further support for p53 involvement was provided by the fact that METH treatment caused significant decreases in dopamine transporter mRNA and the number of tyrosine hydroxylase-positive cells in the substantia nigra pars compacta and the ventral tegmental area of wild-type but not homozygous p53-knockout mice killed 2 weeks after cessation of METH administration. These results provide concordant evidence for a role of the tumor suppressor, p53, in the long-term deleterious effects of a drug acting on brain dopamine systems.     

Immunoblotting of mite aeroallergens collected with an indoor Burkard air sampler

We examined the kinetics of airborne levels of mite allergen particles in a house by combined use of an indoor Burkard air sampler and immunoblotting. Airborne mite allergens collected on the Burkard sampling tape were transferred onto a nitrocellulose membrane, reacted with mouse monoclonal anti-mite allergen (Der pI) antibody, then treated with alkaline phosphatase conjugated anti-mouse IgG. Finally, the blotted allergen on the membrane was reacted with BCIP/NBT phosphatase, and purple spots visible by the naked eye were produced. The shape of the spots was observed under a microscope, and the spot area was measured by an image processor. This technique might be useful for analyzing the behavior of airborne allergen particles in indoor environments.     

Establishment and characterization of a new,spontaneously immortalized,pancreatic ductal cell line from the Syrian golden hamster

Spontaneously immortal pancreatic cell lines are not available. By use of a defined culture medium, such a line (TAKA-1) was established from the Syrian golden hamster. Cytological, cytogenetic, molecular biological, enzymatic and receptor patterns as well as antigenicity were studied and were compared with those of the normal hamster pancreatic ductal cells in vivo. TAKA-1 cells grew exponentially in a monolayer on collagen gel in a defined medium but did not proliferate in soft agar. Ultrastructurally, the cells closely resembled the normal hamster pancreatic ductal cells. Similarities and dissimilarities were found between the normal ductal cells and TAKA-1 cells. Similarities included the presence of cytokeratin, carbonic anhydrase and some tumor-associated antigens. However, unlike the normal ductal cells, TAKA-1 cells expressed blood group A angigen and anti-vimentin, showed affinity to selected lectins, and an abnormality of chromosome 3, which is suggested to be associated with immortality. Moreover, unlike the hamster pancreatic ductal cancer cells but like the normal hamster pancreatic ductal cells, TAKA-1 cells did not have a c-Ki-ras mutation. EGF, TGF- and secretin, but not CCK or GRP, bound to the TAKA-1 cells. TAKA-1 cells produced TGF-, and their growth was stimulated by exogenous EGF in serum-free medium. This cell line presents a suitable model for biologic and pathologic study of the hamster pancreatic ductal cells in vitro.     

Predominant maternal egg care and promiscuous mating system in the Japanese filefish,Rudarius ercodes (Monacanthidae)

Synopsis Reproductive behavior of the Japanese filefish, Rudarius ercodes, was studied at the rocky reef off Koinoura, northern Kyushu, Japan, between June and October 1989. Aggressive display was observed between males, but they were not territorial. Males had four types of courtship behavior: vibrating, tail bending, leaning and nuzzle. Spawning occurred early in the morning. A female and 1–3 male(s) mated together on brown algae. Each female spawned repeatedly with an interval of 6–12 days. Females cared for eggs and embryos from just after spawning until hatching, 2–4 days. Female egg care consisted of tending and guarding. Females tended eggs by blowing water on them and by fanning them with their pectoral fins. Females guarded eggs by driving away fish passing nearby. In some cases, males also guarded eggs by staying near the eggs and driving away conspecific males. Whether a male cares for eggs with a female seems to be affected by the form of mating (pair mating or single female-multiple male mating), and the probability of further reproduction after spawning. Dominant males showed a tendency to pair with a specific female intermittently over a two-month period. Mating, however, did not always occur between members of such pairs, and mates appeared to be inter-changeable with a promiscuous mating system.     

Karyomorphology of some Moraceae and Cecropiaceae (Urticales)

The karyomorphology of 16 species in 13 genera representing Moraceae and Cecropiaceae was investigated in an effort to contribute to a better understanding of chromosome features and evolution in the families. All genera investigated have similar karyomorphology, but differences are found in (1) chromosome features of Interphase nucleus (simple, simple-complex, or complex chromocenter type), (2) basic chromosome number (x=13 or 14), (3) size variation (mono-or bimodial), and (4) frequencies of chromosomes with median centromeres (m-chromosome) (25–85%) and those with subterminal (or terminal) centromeres (st-chromosome) (14–69%). Comparisons with Ulmaceae as an outgroup of the remainder of Urticales suggest that the simple chromocenter type,x=14 comprising bothm- andst-chromosomes, and the monomodial karyotype are plesiomorphies in Moraceae and Cecropiaceae. Most of Moraceae and Cecropiaceae retain generalized chromosome features of the order, but have involved a few evolutionary changes in karyomorphology. Based on some detailed karyomorphological data, inter- and infrafamilial relationships are also briefly discussed.