Impacts of skipping breakfast and late dinner on the incidence of being overweight: a 3-year retrospective cohort study of men aged 20-49 years.

BACKGROUND: Most studies on the dietary habits and overweight status of men aged 20-49 years have been cross-sectional, with longitudinal studies being scarce. One-quarter of Japanese men aged 20-49 years skip breakfast or have dinner within 2 h of bedtime (late dinner); therefore, the effects of these eating habits on men's increasing body weight need to be determined. METHODS: We conducted a retrospective cohort study using health check-up data provided from several health insurance societies in Japan. Participants comprised 45 524 men employees aged 20-49 years who were followed up for 3 years. The primary outcome investigated was body mass index (BMI) ≥25 kg m-2 . We conducted a multivariable logistic regression analysis and calculated the odds ratios for skipping breakfast and late dinner, as well as baseline age, body mass index, smoking status, eating speed, snack-eating status, alcohol drinking frequency, physical activity, sleep habits, and the interaction between skipping breakfast and late dinner. RESULTS: Of the participants, 17 706 (38.8%) skipped breakfast and 25 987 (57.1%) had a late dinner. At the 3-year follow-up, 5093 (11.2%) had a BMI ≥25 kg m-2 . The odds ratios of men skipping breakfast and having a late dinner were 1.18 (95% confidence interval = 1.04-1.33) and 0.92 (95% confidence interval = 0.84-1.01), respectively. The interaction between these factors was nonsignificant. CONCLUSIONS: We suggest that skipping breakfast among men aged 20-49 years was one predictor of being overweight; however, having dinner within 2 h of bedtime was not a predictor.

Multi-decadal survival of an Antarctic nematode, Plectus murrayi, in a -20°C stored moss sample.

It is not clear for how long Antarctic soil nematodes might tolerate freezing. Samples of the Antarctic moss, Bryum argenteum, were collected on 1 October 1983 at Langhovde, Soya coast, eastern Antarctica and were stored at -20°C. After 25.5 years of storage, living nematodes were recovered from the samples and were identified as Plectus murrayi by morphological examination and nucleotide sequencing of ribosomal RNA loci. The nematodes can grow and reproduce in a water agar plate with bacteria (mainly Pseudomonas sp.) cultured from the moss extract. They showed freezing tolerance at -20°C and -80°C and their survival rate after exposure to -20°C, but not -80°C, was increased if they were initially frozen slowly at a high sub-zero temperature. They also showed some ability to tolerate desiccation stress.

Prediction of hypotension during spinal anesthesia for elective cesarean section by altered heart rate variability induced by postural change.

BACKGROUND: Maternal hypotension is a common complication during cesarean section performed under spinal anesthesia. Changes in maternal heart rate with postural changes or values of heart rate variability have been reported to predict hypotension. Therefore, we hypothesized that changes in heart rate variability due to postural changes can predict hypotension. METHODS: A total of 45 women scheduled to undergo cesarean section under spinal anesthesia were enrolled. A postural change test was performed the day before cesarean section. The ratio of the power of low and high frequency components contributing to heart rate variability was assessed in the order of supine, left lateral, and supine. Patients who exhibited a ⩾two-fold increase in the low-to-high frequency ratio when moving to supine from the lateral position were assigned to the postural change test-positive group. RESULTS: According to the findings of the postural change test, patients were assigned to the positive (n=22) and negative (n=23) groups, respectively. Hypotension occurred in 35/45 patients, of whom 21 (60%) were in the positive group and 14 (40%) were in the negative group. The incidence of hypotension was greater in the positive group (P<0.01). The total dose of ephedrine was greater in the positive group (15±11 vs. 7±7mg, P=0.005). The area under the receiver operating characteristic curve was 0.76 for the postural change test as a predictor of hypotension. CONCLUSION: The postural change test with heart rate variability analysis may be used to predict the risk of hypotension during spinal anesthesia for cesarean section.

Differential display analysis of gene expression in developing embryos of Xenopus laevis.

Differential display (DD), an arbitrarily primed RT-PCR fingerprinting technique, is a novel approach for the search of differentially expressed transcripts. Using our improved DD protocol, reproducible cDNA fingerprints were successfully obtained from RNAs of Xenopus laevis embryos at six representative stages. Parallel comparison among the fingerprints revealed a number of bands with differential expression patterns. Analysis with clones of three randomly chosen bands confirmed that their expression patterns were faithfully reflected on fingerprints, thereby proving the reliability and validity of the approach. Nucleotide sequencing of these clones revealed that one is identical with a known transcript (cardiac actin), the second is a novel developmentally regulated gene showing no significant homology with those reported previously, and the last is a close but unique relative of XK endo B gene showing somewhat different spatial expression pattern. These results indicated that the DD analysis provides a rapid and reliable way for the identification of novel differentially expressed genes as well as a unique 'scope' for the survey of the changes in overall gene expression profiles occurring in the early embryonic development of Xenopus as well as of other organisms.

Identification of novel isoforms of human RAD52.

In yeast, RAD52 has been shown to be essential for homologous recombination of DNA and to be involved in the repair of double-stranded DNA breaks. Recently, the human homologue of yeast RAD52, a 418-amino-acid protein, has been identified. In this study, we report three different isoforms of human RAD52 isolated from brain and testis cDNA libraries. cDNAs of these isoforms contain distinct insertions and encode truncated proteins due to translational frame-shifts. The three isoforms consist of 226-, 139-, and 118-amino-acid residues, and are designated as RAD52beta, gamma, and delta, respectively. The original RAD52 is termed as RAD52alpha in this paper. Messages of these isoforms have been detected in various human tissues. We found that the RAD52 isoforms were unable to interact with RAD52alpha because of partial defect of the self-interaction domain. Furthermore, like RAD52alpha, the isoforms have been shown to bind to both single-stranded and double-stranded DNA. These results suggest that RAD52beta, gamma, and delta might affect RAD52alpha function through their DNA-binding property and their inability to bind to RAD52alpha. Thus, these isoforms might act as dominant negative mutants or negative regulators of RAD52alpha.

MCP-1 receptor binding affinity is up-regulated by pre-stimulation with MCP-1 in an actin polymerization-dependent manner.

Monocyte chemoattractant protein-1 (MCP-1) induces monocyte chemotaxis via interaction with the MCP-1 receptor CCR2. We found that MCP-1 binding to monocytic THP-1 cells was increased by pre-treatment with MCP-1. The amount of CCR2 mRNA and the cell-surface expression of CCR2 were not affected by MCP-1 stimuli. In contrast, the MCP-1-treated THP-1 cells showed a sixfold increase in MCP-1 binding affinity compared with untreated cells. MCP-1 binding to CCR2B-transfected HEK-293 cells was also enhanced by pre-treatment with MCP-1, and MCP-1 binding affinity increased by sixfold. In both cell lines, the enhancement of MCP-1 binding by stimulation with MCP-1 was blocked by cytochalasin D, an inhibitor of actin polymerization. This effect of pre-treatment with MCP-1 is insensitive to pertussis toxin and partially blocked by U73122, an inhibitor of phospholipase C. These results demonstrate that the MCP-1 receptor binding affinity is up-regulated by MCP-1 stimuli in an actin polymerization-dependent manner.

Fluorescent differential display analysis of gene expression in differentiating neuroblastoma cells.

Identification of differentially-expressed genes provides an important step toward the elucidation of molecular mechanisms underlying a variety of biological processes. A novel PCR-based approach to detect and clone such transcripts is the so-called differential display (DD). We established an improved DD protocol that can be performed on an automated fluorescent DNA sequencer to ensure high throughput as well as operational safety. Using this fluorescent DD (FDD) technique, we analyzed the gene expression profile in the retinoic acid-induced differentiation of a human neuroblastoma cell line SH-SY5Y. Screening with 102 primer combinations at eight different time points revealed 66 cDNA bands with variously different behaviors out of approximately 6000 bands displayed. Subsequent analyses with 15 cloned species confirmed the differential expression of corresponding transcripts in all the cases, thereby demonstrating the high reliability of FDD analysis. These clones were composed of seven novel and eight known genes, the latter of which included those that had never been described in the context of neuronal differentiation. These results indicate that FDD is an effective approach to obtain not only novel genes but also clues to possible novel functions of known genes involved in various biological phenomena.

Fluorescent differential display: arbitrarily primed RT-PCR fingerprinting on an automated DNA sequencer.

We established robust, reliable protocols for 'Differential Display (DD),' an RNA fingerprinting method originally developed by Liang and Pardee [(1992) Science 257, 967-971] using RT-PCR with arbitrary primers. Our protocols are optimized so that reliable DD analysis can be performed on a fluorescent DNA sequencer to ensure high throughput as well as improved operational safety, compared with the original one using radioactive compounds. Such 'Fluorescent Differential Display (FDD)' techniques will accelerate the identification of differentially expressed as well as polymorphic transcripts to address various biological questions.

Age changes of myofibrils of human minor pectoral muscle.

Micro- and ultramicromeasuring studies have been made on the age changes of surgically resected minor pectoral muscles in 200 Japanese females of various ages (26-80 years). With advancement of age, muscle fibers of type I decreased in number and increased in size, and the age-related increase in size is not considered to be due to an increase in number of myofibrils but seems to be due to an increase in their volume resulting from an increase in the number of myofilaments.

Age changes in size and number of muscle fibers in human minor pectoral muscle.

Micromeasuring studies have been made on the senile changes of the surgically resected minor pectoral muscles in 200 Japanese females of various ages (26-80 years). The microscopic differentiation between type I (red) and type II (white) fibers were made by the histochemically demonstrated myosin-ATPase activity with frozen sections and also by the immunohistochemical demonstration of beta-enolase in the paraffin sections with indirect antibody method. The decrease with age in weight of the muscle was not markedly observed. Muscle fibers of type I were significantly decreased in number and increased in size after 60 years of age. However, size of muscle fibers of type II decreased gradually after 40 years of age. However, size of muscle fibers of type II decreased gradually after 40 years of age. Total volume of type I muscle fibers was not changed according to age, on the contrary, that of the type II fibers decreased significantly after 60 years of age.

Enhanced expression of PP1 gamma 1, a catalytic subunit isoform of protein phosphatase type 1, in invasive ductal carcinoma of the breast.

Breast cancer is one of the most common malignancies of women. Assessing the biological parameters of malignant tumors may facilitate predictions of clinical outcome. The expression of the three catalytic subunits of protein phosphatase (PP) type 1, PP1 alpha, PP1 gamma 1 and PP1 delta, as well as the one catalytic subunit of PP type 2, PP2AC, were examined in ten cases of mammary dysplasia, ten cases of fibroadenoma and 12 cases of invasive ductal carcinoma, using immunohistochemical analysis. Moreover, we measured the S-phase fraction of the cell cycle for use as a marker value of cell growth, using flow cytometric analysis. The percentage of proliferating cells that stained positive with antisera against PP1 gamma 1 was significantly higher in invasive ductal carcinoma than in mammary dysplasia and fibroadenoma. Furthermore, invasive ductal carcinoma showed a markedly high number of tumor cells in the S-phase of the cell cycle, as compared to mammary dysplasia and fibroadenoma. Our results indicate that PP1 gamma 1 may be involved in the accelerated growth of malignant cells in breast tumors.

Lactate and pH mapping in calf muscles of rats during ischemia/reperfusion assessed by in vivo proton and phosphorus magnetic resonance chemical shift imaging.

RATIONALE AND OBJECTIVES: Metabolic images of phosphocreatine, inorganic phosphate (Pi), and pH formed by phosphorus 31 (31P) nuclear magnetic resonance (NMR) spectroscopy, that of lactate by proton (1H) NMR spectroscopy and 1H magnetic resonance imaging (MRI) were concurrently observed using the same ischemia/reperfusion model in the calf muscles of rats. From the multidimensional analyses, the correlation between tissue pH and lactate formation was examined. METHODS: Six rats were used in the study. For the selective detection of lactate by 1H NMR, a multiple quantum coherence filter was used. The localization of the metabolites and pH was achieved by three-dimensional chemical shift imaging technique. These observations were repeated in 1-hour cycles during 6 hours of ischemia and after reperfusion. RESULTS: The tibialis anterior and gastrocnemius muscles, which are mainly composed of fast-twitch muscle fibers, showed severe tissue edema and irreversible phosphoenergetic change. These muscles became more acidic than other portions of the calf. In contrast, the central part of the calf including soleus muscle (slow-twitch muscle) showed reversible phosphoenergetic changes. Lactate accumulated mainly between the muscles showing reversible and irreversible phospho-energetic changes. CONCLUSION: Discrepancy between acidosis and lactate accumulation in calf muscles was observed in this ischemia/reperfusion model, although the exact reasons for this phenomenon could not be explained by this study.

Effects of estrogen on the turnover rates of ornithine amino transferase in rat liver and kidney.

The turnover rates of ornithine aminotransferase in the liver and kidney of control rats and those treated with estrogen were determined by injecting L-[14C]leucine (U) and following the decay of specific radioactivity incorporated into immunoprecipitates from the partially purified enzymes. The half-life of the ornithine aminotransferase [EC 2.6.1.13] in the liver (t1/2=0.95 days) was significantly different from that of the kidney enzyme (t1/2=4.0 days). Studies on the incorporation of radioactive leucine into ornithine aminotransferase in the kidney under steady-state conditions showed that the rate of synthesis of this enzyme after treatment with estrogen was 5 to 6 times higher than that in untreated animals. The rate constant of degradation of kidney ornithine aminotransferase under steady-state conditions induced by estrogen treatment was not significantly different from that under control conditions. The results showed that the increase in the rate of biosynthesis, not to a decrease in the rate of degradation. No significant changes in the rates of biosynthesis and degradation of liver ornithine aminotransferase were observed after administration of estrogen.

Mode of inhibition of ornithine aminotransferase by L-canaline.

The mechanism of inhibition of ornithine aminotransferase [EC 2.6.1.13] by L-canaline (alpha-amino-gamma-amino-oxybutyric acid) was investigated. Spectral changes of pyridoxal 5'-phosphate in ornithine aminotransferase on addition of L-canaline showed that L-canaline formed an oxime-type compound with pyridoxal 5'-phosphate that had the same spectra as the compound formed on addition of hydroxylamine to the holoenzyme. Kinetic studies indicated that hydroxylamine was a reversible noncompetitive inhibitor, whereas L-canaline was an irreversible inhibitor of ornithine aminotransferase. Other analogs, such as delta-aminovaleric acid and alpha-N-acetyl-L-ornithine, also reacted with the pyridoxal 5'-phosphate of the enzyme, but these compounds were competitive inhibitors with respect to L-ornithine. L-Canaline and hydroxylamine also reacted with pyridoxal 5'-phosphate in pig heart aspartate aminotransferase [EC 2.6.1.1] to produce an oxime, but both of them were reversible and noncompetitive inhibitors of the enzyme. The Ki value of hydroxylamine for ornithine aminotransferase was 4.3 X 10(-7) M and those of L-canaline and hydroxylamine for aspartate aminotransferase were 1.7 X 10(-4) M and 2.2 X 10(-5) M, respectively.

Abnormal expression of a serine protease in human dystrophic muscle.

The activities of serine protease in muscles from normal persons and from patients with progressive muscular and neuromuscular diseases have been determined. A significant increase in the level of serine protease was found in muscle of patients with Duchenne-type muscular dystrophy and with Becker-type muscular dystrophy, but the activity was not increased in muscle of a patient with amyotrophic lateral sclerosis.

Monoclonal antibody (VOM2) specific for the luminal surface of the rat vomeronasal sensory epithelium.

Monoclonal antibodies were raised and selected for reactivity with the luminal surface of the rat vomeronasal organ. Among the monoclonal antibodies generated, the one named VOM2 showed specific immunoreactivity within the luminal surface of the rat vomeronasal sensory epithelium. The VOM2 antigen appeared weakly on the luminal surface at postnatal day 14 (P14). After P21, VOM2 immunoreactivity as strong as that in the adult vomeronasal organ was observed. Immunofluorescence staining using VOM2 antibody showed no reactivity on the luminal surface of the adult mouse or hamster vomeronasal organ. An immunoblotting analysis showed that the VOM2 antigen was a protein with a molecular weight of 24,500.

Imaging of phosphoenergetic state and intracellular pH in human calf muscles after exercise by 31P NMR spectroscopy.

Phosphoenergetic and pH images in human calf muscles before and after ischemic exercise were generated by 31P NMR chemical shift imaging (CSI) with a 1.5 T standard clinical MR machine using a home-built volume coil. Acquisition of data was repeated four times with 8 x 8 phase-encoding steps and 1 s repetition time. The total acquisition time was 4 min 16 s. After 3-dimensional (3D) Fourier transformation with zero-filling, 2-dimensional (2D) images with 32 x 32 matrices of phosphocreatine (PCr), inorganic phosphate (Pi), PCr/(PCr + Pi) and pH were constructed. These metabolic images were overlaid with concurrently observed 1H MRI to locate the areas showing metabolic response. After 3 min exercise consisting of repeated plantarflexion of the foot under ischemic conditions, decreases in phosphoenergetic levels and acidosis were the most severe in the peroneus muscles, moderate in the tibialis anterior muscle, and slight in the triceps muscle of the calf. Under maintained ischemic conditions, phosphoenergetic level further decreased, but the acidosis in each muscle did not progress further. Heterogeneous metabolic and pH changes throughout the entire calf muscle were clearly demonstrated in detail by these images.

Incidence of p53 and ras gene mutations in DMBA-induced rat leukemias.

Leukemia, a form of haematological malignancy, is a multi-stage disease and a wide range of diverse genes has been speculated to correlate with its initiation and development. Ras has been speculated to be an initiating gene for haematological malignancy, but more investigation will be needed to determine the genes associated with the progression of the disease. 7,12-dimethylbenz(a)anthracene (DMBA)-induced rat leukemia provides a good tool for research into various stages of the disease. The entire coding regions of p53 and ras genes were examined for mutations in the present study. In this experiment, we used fluorescence-labeled polymerase chain reaction single-stranded conformation polymorphism analysis (PCR-SSCP) and direct sequencing to detect mutations of both genes on rat erythroleukemia. Fifteen out of 18 (83.3%) rat leukemias were found to have N-ras codon 61 mutation, consistent with previous results. The result of direct sequencing showed a single base substitution (CAA to CTA), resulting in an amino-acid change from Gln to Leu. No mutations were found in H-ras, K-ras or codon 12 of N-ras. The incidence of p53 gene mutation was 16.6% (3/18) in rat leukemia at late-stage. In the present study, mutation of the p53 gene was detected in three DMBA-induced leukemias as follows: a single-base substitution (CAT to CGT) at codon 177 (exon 5), resulting in an amino-acid change from Arg to Leu, a CGG to CTG/CGG changed at codon 211 (exon 6) resulting in an amino-acid change from His to Arg/His, and a GGG to TGG at codon 242 (exon 6) resulting in an amino-acid change from Gly to Trp, respectively. Thus, mutations of p53 gene do not seem to respond to the carcinogenesis of the DMBA-induced leukemia, in contrast to mutation of the N-ras oncogene, and may possibly be involved in the progress of multi-stage leukemogenesis.

Duodenum-preserving resection of the pancreatic head for mucinous ductal ectasia without overt carcinoma.

BACKGROUND/AIMS: The clinical characteristics of mucinous ductal ectasia (MDE) of the pancreas without overt carcinoma have not been clarified. To clarify MDE and assess the optimal treatment procedure, including the technique of duodenum-preserving resection of the pancreatic head (DpRPH), we studied four patients. METHODOLOGY: Our patients consisted of three men and one woman, with a mean age of 71 years. The patients underwent DpRPH (n=3) or the pylorus-preserving Whipple procedure (PpW) (n=1). Clinicopathological features, postoperative pancreatic function, and technique to preserve duodenal blood flow were studied. RESULTS: All patients had intraductal mucin-hypersecretion and multilocular cysts lined by hyperplastic epithelium. The lesions were located in the uncinate process (n=3) or head-body (n=1) of the pancreas. DpRPH totally removed the lesions in the uncinate process. Of the three patients receiving DpRPH, dusky duodenum and a postoperative duodenal ulcer developed in two whose gastroduodenal arteries (GDA) were divided, but did not develop in one with undivided GDA. Postoperative glucose tolerance test and peptide para-aminobenzoic acid test after DpRPH showed better values than those after PpW. All patients are alive and well 22 to 40 months after surgery. CONCLUSIONS: DpRPH is a new standard for MDE. During DpRPH, preservation of the GDA and the superior portion of the pancreatic head is recommended to maintain an adequate duodenal blood flow.