Consumer power as the major evolutionary force

Each trophic level in evolving ecosystems can behave as either a supplier toward the downstream of trophic energy flow or a consumer toward the upstream, or an arbitrary mixture of the two. We show that each trophic level behaves almost completely as a consumer in evolutionarily sustainable ecosystems. The present prevalence of consumers in evolving ecosystems derives from a model trophic dynamics minimizing the artificial constraints to be applied arbitrarily.

The identification of proliferating cell nuclear antigen (PCNA) on rat tissue cryosections and its application to double immunostaining with other markers

Proliferating cell nuclear antigen (PCNA) in a useful marker for monitoring cell proliferation in most species. The immunostaining of PCNA on tissue cryosections, however, has been hampered by a loss of PCNA immunoreactivity during the staining process. The need for both identifying the actual phenotypes of proliferating cells and differentiating them from other tissue components prompted us to establish reliable techniques for PCNA immunostaining on cryosections and to apply these to double immunostainings with other markers. We tested various fixing conditions for rat tissue cryosections and the effect derived from unmasking with pepsin digestion to restore PCNA immunoreactivity after fixation. For single immunostainings, the unmasking was effective in most fixing conditions tested. Particularly, 4% paraformaldehyde/0.05% glutaraldehyde fixation followed by 0.001% pepsin digestion resulted in the strongest immunoreactivity for PCNA and the best morphology, and was the first choice for double immunostainings with relatively stable second antigens. Alternatively, periodate-lysine-paraformaldehyde fixation was also applicable to other second antigens which are labile to the former treatment. These techniques can serve in the collection of important information from frozen tissues regarding the relationship between PCNA and other markers of interest which are usually susceptible to routine formalin and/or paraffin embedding.

Primary hemostasis during women's life cycle measured by Thrombostat 4000

The Thrombostat 4000 was used to investigate primary hemostasis in women during different stages of their life cycle. Nonpregnant females were studied during their proliferative and luteal phases; pregnant women were investigated during their 28-35th weeks of gestation and some women between the ages of 70-84. Data were compared to those obtained from male volunteers injected with 40 mg estrogen. No significant differences between proliferative and luteal phases were found, but BT2 was prolonged in the elderly women. In the pregnant women extremely short BT2 values were measured. Shortening of BT2 was also seen in the males injected with estrogen.

Slow and macroscopic modulation of thermal fluctuations in myofibrils

A comparison was made between fluctuations in a length of sarcomere from a myofibril during relaxed and rigor conditions. The fluctuations of the length associated with rigor states was due entirely to thermal fluctuations in the ambient. In contrast, the fluctuations associated with relaxed states were accompanied by extremely slow and macroscopically modulated thermal fluctuations. A slow, macroscopic modulation of the thermal fluctuations of the length of sarcomere was found to be unique to myofibrils in their relaxed conditions.

ATP hydrolysis and sliding movement of actomyosin complex in the presence of ethanol

We measured both the ATPase activity of actomyosin complex and the sliding velocity of actin filaments on myosin heads under hydrophobic conditions in the presence of ethanol. Both the ATPase activity and the sliding velocity decrease with the increase of ethanol concentration, if the ionic strength is not too high. As ionic strength increases, there appears an optimum concentration of ethanol that can enhance both the ATPase activity and the sliding velocity.

Acute effects of sigma ligands on the extracellular DOPAC level in rat frontal cortex and striatum

Acute administration of (+)-N-allylnormetazocine ((+)-SKF-10,047) and (+/-)-pentazocine, was found to increase the extracellular level of 3,4-dihydroxyphenylacetic acid (DOPAC), a major dopamine (DA) metabolite, in the rat frontal cortex. By contrast, these benzomorphan sigma ligands did not change the extracellular DOPAC level in the rat striatum. On the other hand, 1,3-di(2-tolyl)guanidine (DTG) increased the extracellular DOPAC level in the frontal cortex, while it decreased that level in the striatum. Another non-benzomorphan sigma ligand, (+)-3-(3-hydroxyphenyl)-N-(1-propyl)piperidine ((+)-3-PPP) decreased the extracellular DOPAC level in both frontal cortex and striatum. Moreover, the increase of the extracellular DOPAC level elicited by (+)-SKF-10,047 was significantly inhibited by rimcazole, a putative sigma antagonist, while the DTG-induced increment was not reversed by rimcazole. These findings indicated that the effects of sigma ligands on the mesocortical DA neurons differed from those on the nigrostriatal DA neurons. In addition, the effects of benzomorphan sigma ligands on the central DA neurons were different from those of non-benzomorphan sigma ligands.

Identification of DNA-binding proteins changed after induction of sporulation in Bacillus cereus

DNA-binding proteins were extracted from both exponentially growing cells of Bacillus cereus ts-4 and cells that were induced to sporulate at different stages of chromosome replication, by using a double-stranded B. cereus ts-4 DNA-cellulose column. Two-dimensional electrophoresis of the proteins found that the amounts of 17 proteins changed drastically after induction of sporulation at all the stages. For 8 of those proteins, the largest or the smallest amount was found in the cells which were induced to sporulate 40 min after the initiation of chromosome replication, the sensitive stage for sporulation. The N-terminal amino acids of 6 proteins among the selected proteins were sequenced. The sequence obtained from a 59-kDa protein had sequence similarity (> 45%) to GroEL from several bacterial species. In addition, the sequences from 76- and 52-kDa proteins matched deduced amino acid sequences of a Mycobacterium leprae gene showing homology to the bacteria atp operon and the B. subtilis guaB for IMP dehydrogenase, respectively.

Quantum and biological computation

Ubiquitous internal measurement of material origin and conservation laws, when combined together, uphold biological computation as a specific mode of quantum computation. Internal measurement supplemented by conservation laws can reproduce quantum mechanics or the uncertainty principle in particular. Furthermore, biological computation founded upon internal measurement provides an irreversible enhancement of organization and quantum coherency through non-algorithmic and non-programmable procedures of generating variations in accordance with the operation of the uncertainty principle.

Cholesteryl ester transfer protein gene: two common mutations and their effect on plasma high-density lipoprotein cholesterol content

Cholesteryl ester transfer protein regulates high-density lipoprotein cholesterol (HDL-C) level, and genetic deficiency causes hyperalphalipoproteinemia (HALP). The G to A mutation in the intron 14 splice donor (I14A) has been known to be a common mutation in HALP. Recently, another mutant, D442G (Asp 442 to Gly), was ascertained. The allelic frequencies of I14A and D442G were investigated using 226 unrelated patients with HDL-C of 1.03 mmol/L (40 mg/dL) or greater. Of these, 44 had a mutation I14A and/or D442G. The I14A was found in 15, including 4 compound heterozygotes (I14A/D442G) in patients with HDL-C of 2.05 mmol/L (80 mg/dL) or greater. All I14A homozygotes (n = 5) were present in the group with HDL-C of 3.08 mmol/L (120 mg/dL) or greater, and the allelic frequency paralleled the increase in HDL-C level. D442G was identified in 33, including the 4 compound heterozygotes. Its allelic frequency appeared as two clusters, one at HDL-C around 1.79-2.03 mmol/L (70-79 mg/dL) and the other at HDL-C of 2.82 mmol/L (110 mg/dL) or greater; the latter consisted exclusively of compound heterozygotes. Allelic frequency in the general population for I14A and D442G was 0.81% and 4.62%, respectively. These data suggest that D442G is a common mutation and that, although I14A is responsible for the most severe HALP, D442G leads to a relatively smaller increase in HDL-C.

ALDH2 polymorphism and biological monitoring of toluene

In this study, we evaluated the effects of the genetic polymorphism of ALDH2 (low Km aldehyde dehydrogenase) on toluene metabolism and determined biological exposure indices (BEIs) of the genotypes of ALDH2. The study subjects included 45 toluene workers and 122 nonexposed students. The genotype of ALDH2 was classified into the homozygous genotype of normal ALDH2 (NN), the homozygous genotype of an inactive one (DD), and the heterozygous genotype of normal and inactive ones (ND) by means of artificial-RFLP. The personal exposure levels to toluene were monitored, using diffusion type samplers and urinary hippuric acid (HA) and creatine concentrations were determined. The urinary HA levels of the three genotypes of ALDH2 of nonexposed students did not differ. In the toluene workers, positive correlations between the personal exposure to toluene and urinary HA levels were observed in the NN, ND, and DD groups. The urinary HA level of the DD group was significantly lower than that of the NN or ND group. Regression lines were used to estimate the BEIs of the NN, ND, and DD groups, which were approximately 2.9 g/g creatinine, 3.3 g/g creatinine, and 1.9 g/g creatinine, respectively.

Ameliorating effects of sigma receptor ligands on the impairment of passive avoidance tasks in mice: involvement in the central acetylcholinergic system

Three sigma receptor ligands were examined for their ameliorating effects on p-chloroamphetamine-induced amnesia in mice. p-Chloroamphetamine was administered intraperitoneally 30 min before the training session of the passive avoidance response. Each sigma receptor ligand was administered 60 min before or immediately after the training session, or 60 min before the retention test. (+)-N-Allylnormetazocine ((+)-SKF-10,047), a prototype benzomorphan sigma receptor ligand, significantly reduced the p-chloroamphetamine-induced amnesia in these three administration schedules, as do acetylcholinesterase inhibitors. On the contrary, the significant anti-amnesic effects elicited by non-benzomorphan sigma receptor ligands, 1,3-di-(2-tolyl)guanidine (DTG) or (+)-3-(3-hydroxyphenyl)-N-(1-propyl)piperizine ((+)-3-PPP), were observed depending upon the timing of their administration. In addition, the ameliorating effect of (+)-SKF-10,047 against the p-chloroamphetamine-induced amnesia was superior to that of (-)-SKF-10,047. The (+)-SKF-10,047-induced anti-amnesic effect was significantly antagonized by the concurrent administration of either scopolamine, a muscarinic receptor antagonist, or hemicholinium-3, an inhibitor of the Na(+)-dependent high-affinity choline uptake site. These findings indicated that sigma receptor ligands had anti-amnesic effects against drug-induced memory impairment. In addition, the anti-amnesic effect of (+)-SKF-10,047 was superior to those of other sigma receptor ligands, and was mediated by both the sigma receptor and the central acetylcholinergic system.

Efficiency of serum copper/zinc ratio for differential diagnosis of patients with and without lung cancer

We examined serum copper (Cu), serum zinc (Zn), and the serum copper/zinc ratio (Cu/Zn) in 162 patients. All of them were seen to have an abnormal shadow in the chest X-ray films, that is, 109 patients with lung cancer (LC) and 53 patients with no lung cancer (NLC). The mean Cu and Cu/Zn in LC patients were significantly higher than those in NLC patients (p < 0.05). In LC patients, Cu and Cu/Zn were higher and Zn was lower in advanced tumors than early ones. There was a significantly clear relation between Cu or Cu/Zn and the tumor (T) stages. When the relative risk (RR) of LC was estimated, it was seen that the higher Cu and Cu/Zn became, the higher RR became. Furthermore, we showed the sensitivity of the receiver operator characteristic of the test (ROC) curve for Cu, Cu/Zn, and carcinoembryonic antigen (CEA) to diagnose LC, as explained in a paragraph of methods. The determinations of Cu, Zn, and Cu/Zn are simple and inexpensive. They also appear to have a great diagnostic value in determining the local invasion of LC and as a screening test in the high-risk patients for LC.

[Automated simultaneous measurements of activity and antigenicity of plasma antithrombin III]

Plasma antithrombin III activity and concentration were measured simultaneously on COBAS MIRA-S by colorimetry using a synthetic substrate and by immunoturbidimetry, respectively, in normal subjects (n = 30), in patients with liver disease (n = 37), and in those with thrombosis (n = 76). The activity/concentration ratio of plasma antithrombin III, in which concentration was represented as the ratio to the mean concentration for normal, was evaluated in each group. Results showed that the ratio was significantly lower in patients with liver diseases (0.76 +/- 0.18, mean +/- SD, p < 0.01) and in thrombotic patients (0.89 +/- 0.18, p < 0.01) than that in normal (1.07 +/- 0.06), demonstrating the predominance of antithrombin III molecules with low activity in the former groups. This simple and rapid (< 10 min) method is applicable for detecting such the constitutional change in plasma antithrombin III.

Appraisal of the clinical competence of registered nurses in relation to their designated levels in the Western Australian nursing career structure

This cross-sectional survey examined the relationship of the competence of 529 nurses to their designated career structure levels. The extent of the relationships between nursing education and experience with clinical competence was determined, and attitudes of nurses toward their work environment were measured. Results indicated a wide dispersion in clinical nursing skills and that nurses' designation in the Western Australian Career Structure did not reflect their clinical competence. Clinical experience and education independently exerted a significant effect on competence, but there was no interaction between these variables on increasing competence. Attitudes of the nurses were found to be affected by their work environment.

[Medical examination of workers exposed to lead in the Philippines]

The medical examination of workers exposed to lead was conducted as part of the activity of the Occupational Safety and Health Center (OSHC) Project in the Philippines (JICA Project). The subjects of the medical examination were 21 male and 193 female workers of a semi-conductor plant (abbreviated A company), 59 male and 6 female workers of a refrigerator manufacture (B company); 199 male workers of a storage battery manufacturer (C company); and 107 male and 6 female workers of a lead smelter (D company). Among the examination items were questions regarding occupational history, subjective complaints and objective signs, determination of blood lead levels, urine delta aminolevulinic acid levels, and examination for anemia. The survey was conducted from June to September in 1990. The following results were obtained: 1) The mean age of the workers ranged from 21.8 to 33.8 years. Those of companies A and B were younger than those of companies C and D. The mean employment duration of males at C company was 10.7 yr, and the longest among the four companies. That in both sexes for A company was 1.8 yr and the shortest among the above mentioned companies. 2) The blood lead geometric mean levels of companies C and D showed the highest concentration. The level in males of C company was 64.5 micrograms/dl and that of D company was 80.8 micrograms/dl. The level in females of A company was 9.9 micrograms/dl and the lowest in concentration. The urine delta aminolevulinic acid geometric mean levels were less than 6.0 mg/l in the four companies. There was no company having hemoglobin mean values less than 14.0 g/dl in males or less than 12.0 g/dl in females. 3) The proportion of blood lead levels of 60 micrograms/dl or more was 67.3% in males of C company, and 89.7% in males and 16.7% in females of D company. The proportion of urine delta aminolevulinic acid levels of 6 mg/l or more was 1.0% in females of A company, 20.1% in males of C company, and 43.0% in males of D company. The proportion of hemoglobin values less than 14.0 g/dl in males or less than 12.0 g/dl in females was 4.7% in females of A company, 1.7% in males of B company, 3.5% in males of C company, and 12.1% in males of D company.(ABSTRACT TRUNCATED AT 400 WORDS)

Cytosolic interaction between deltex and Notch ankyrin repeats implicates deltex in the Notch signaling pathway

Genetic data from Drosophila have suggested a functional relationship between the novel cytoplasmic protein encoded by the deltex locus and the transmembrane receptor encoded by Notch. We have demonstrated a direct interaction between these proteins from expression studies conducted in cultured cells, in yeast, and in the imaginal wing disc. deltex binds specifically to the Notch ankyrin repeats, a region that is crucial for Notch signaling and that constitutes the most conserved domain among Notch family members. In addition, we present a new Notch allele, Nsu42c, that is associated with a missense mutation within the fifth ankyrin repeat. In addition to representing a new class of viable Notch allele, this mutation behaves similarly to mutations of deltex and further implicates the ankyrin repeats in Notch function.

Promoter of the POU-M1/SGF-3 gene involved in the expression of Bombyx silk genes

To characterize the transcription regulation of the POU-M1/SGF-3 gene, we have cloned a genomic DNA fragment encompassing the whole coding region and its flanking sequences. This gene does not contain any intron. The 5'-flanking region of the gene contains several interesting motifs, such as homeodomain-binding motifs, sequences resembling the transcriptional factor Sp1-binding site, and TGTTT motifs, but lacks some of the typical transcriptional regulatory sequences, such as TATA and CCAAT boxes. Transcriptional analysis of a series of deletion mutants of the gene in the nuclear extracts prepared from the middle silk gland of 2-day-old fifth instar larvae revealed the presence of multiple cis-regulatory elements located both upstream and downstream of the initiation site. One of these elements, the homeodomain-binding element, was identified to mediate negative regulation. By mobility shift assay using the POU-M1 specific antibodies, we found that this negative element interacts with the POU-M1/SGF-3. Transcription analysis in vitro using templates mutagenized in the PB region and one of the POU-M1 antibodies indicated that the PB region is an autoregulatory element responsible for SGF-3-dependent transcriptional repression.

Electron spin resonance studies of free radicals in gamma-irradiated golden hamster embryo cells: radical formation at 77 and 295 K, and radioprotective effects of vitamin C at 295 K

Formation of free radicals in golden hamster embryo (GHE) cells produced by gamma irradiation at 77 and 295 K has been studied by electron spin resonance (ESR) spectroscopy. The yields of free radicals in the gamma-irradiated frozen cells at 77 K increase linearly with increasing dose in the range from 8 Gy to 1.3 kGy, suggesting that the mechanism of radical formation at a dose of 8 Gy is the same as that at 1.3 kGy. When GHE cells are irradiated with 5 kGy gamma rays at 295 K and then the ESR spectrum is measured at 77 K, a part of the organic radicals produced can be observed clearly. The organic radicals survive in GHE cells for more than 24 h at room temperature. The formation of the organic radicals by gamma irradiation is suppressed upon the addition of vitamin C to the GHE cells. When an aqueous solution of albumin (0.1 kg dm-3) is gamma-irradiated with 5 kGy at 295 K, albumin radicals are observed by ESR. The formation of the albumin radicals is suppressed drastically upon the addition of vitamin C. The efficient radioprotection of vitamin C against radical formation has been interpreted in terms of the scavenging of albumin radicals by vitamin C.

Personal exposure to nitrogen dioxide from indoor heaters and cooking stoves

The personal exposure to NO2 generated from various heaters and cooking stoves were studied, using 85 university students. The students attached NO2 filter badges to their chests or collars and wrote down the period of time for heating and cooking for 1 week. Types of heaters and smoking habits were described through a questionnaire. The urinary hydroxyproline/creatinine ratio (HOP/C) was examined as a biomarker for health effects. The outdoor NO2 concentration during the study period was 13.5-13.7 micrograms/m3. Smoking and the usage of electric heaters did not affect the exposure to NO2. Exposure increased according to the length of time kerosene heaters or oil fan heaters were used. The NO2 concentration during the heating by a kerosene heater and an oil fan heater was calculated to be 219 and 474 micrograms/m3, respectively. The correlation between the period of cooking and personal exposure was also observed. The NO2 levels during cooking were calculated to be 290 micrograms/m3. Using these calculated values of NO2 concentration, it is possible to presume the personal exposure levels from the length of time heaters and cooking stoves are used even if the subjects do not attach the filter badges. Neither smoking nor exposure to NO2 were associated with the increase of urinary HOP/C.

Molecular cloning of a POU domain-containing factor involved in the regulation of the Bombyx sericin-1 gene

The POU domain is a highly conserved region found in a number of transcription factors and products of developmental control genes. We report here the isolation and characterization of a POU domain-containing cDNA (POU-M1) from the middle silk gland of Bombyx mori. It encodes a protein with a POU domain identical to that of the Drosophila Cf1-a protein. By mobility shift and nuclease protection assays, the POU-M1 protein and the putative silk gland factor 3 (SGF-3) were found to interact in an indistinguishable manner with the SC region (positions -204 to -183) of the sericin-1 gene, a key cis-acting element involved in the regulation of the gene through the interaction with SGF-3. Antibodies raised against the synthetic oligopeptide corresponding to the COOH-terminal region of the putative POU-M1 sequence reacted specifically to both the POU-M1 protein and SGF-3. Northern blot hybridization and Western blotting revealed that POU-M1 expression is regulated both temporally and spatially during silk gland development. We conclude that the POU-M1 protein is SGF-3 and propose that the differential expression of the POU-M1 gene is probably involved in the transcriptional regulation of the silk protein genes.