Structure and chemical synthesis of a biologically active form of renilla (sea pansy) luciferin

The structure of a biologically active form of Renilla (sea pansy) luciferin has been elucidated; this structure, confirmed by total chemical synthesis, is 3,7-dihydro-2-methyl-6-(p-hydroxyphenyl)-8-benzylimidazo [1,2-a] pyrazin-3-one. In the natural compound the methyl group at the 2 position is replaced by an unknown, more complex group. For this reason the synthetic compound is 10% as active as the natural compound in producing light with Renilla luciferase. However, the spectral properties of the two compounds are identical. In addition the rates of the luminescent reaction with both compounds are similar, and the color of the light produced is identical in each case.A compound isolated from the calcium-triggered photoprotein aequorin has been identified by Shimomura and Johnson [(1972) Biochemistry 11, 1602] to be 2-amino-3-benzyl-5-(p-hydroxyphenyl)pyrazine. This compound forms an integral part of the structure of Renilla luciferin. This, and other evidence, suggests that the structure elucidated for Renilla luciferin is a more general one associated with the luciferins of most, if not all, bioluminescent coelenterates.

Structure of native Renilla reinformis luciferin

The structure of native luciferin from the bioluminescent coelenterate Renilla reniformis is shown to be 3,7-dihydro-2-(p-hydroxybenzyl)-6-(p-hydroxyphenyl)-8-benzylimidazo[1,2-a]pyrazin-3-one by mass spectral analysis of synthetic luciferin and the luciferin derived from a protein directly involved in the bioluminescent system. A previous report of the molecular weight of luciferin is shown to be incorrect by reexamination of the spectral data and by synthesis of two derivatives. Detailed analysis of kinetic, emission, and quantum yield data for the isolated and synthetic luciferins confirms this structure. Confirmation of this structure in a number of species from different phyla suggests a common substrate for a variety of bioluminescent marine organisms.

Age-related Changes in Tongue Pressure during Swallowing

Although swallowing movement is known to change with aging, age-related differences in the tongue pressure for propelling a bolus from the oral cavity into the pharynx have yet to be investigated in a physiological condition. We hypothesized that tongue pressure during swallowing changed with aging and, using a 0.1-mm-thick sensor sheet with 5 measuring points, measured it while a 15-mL quantity of water was swallowed by young and elderly dentate individuals. Both groups showed a similar order of tongue pressure production at each point. However, the elderly group showed longer duration at each point, lower maximal magnitude in the anterio-median part of the hard palate, and higher magnitude in the circumferential parts of the hard palate than the young group. These results provide the first quantitative evidence of the age-related changes in tongue movement during natural swallowing, which could be attributed to muscle weakening and morphological changes in the oropharynx.

CO2 insufflation for potentially difficult colonoscopies: Efficacy when used by less experienced colonoscopists

AIM: To clarify the effectiveness of CO₂ insufflation in potentially difficult colonoscopy cases, particularly in relation to the experience level of colonoscopists.

METHODS: One hundred twenty potentially difficult cases were included in this study, which involved females with a low body mass index and patients with earlier abdominal and/or pelvic open surgery or previously diagnosed left-side colon diverticulosis. Patients receiving colonoscopy examinations without sedation using a pediatric variable-stiffness colonoscope were divided into two groups based on either CO₂ or standard air insufflation. Both insufflation procedures were also evaluated according to the experience level of the respective colonoscopists who were divided into an experienced colonoscopist (EC) group and a less experienced colonoscopist (LEC) group. Study measurements included a 100-mm visual analogue scale (VAS) for patient pain during and after colonoscopy examinations, in addition to insertion to the cecum and withdrawal times.

RESULTS: Examination times did not differ, however, VAS scores in the CO₂ group were significantly better than in the air group (P < 0.001, two-way ANOVA) from immediately after the procedure and up to 2 h later. There were no significant differences between either insufflation method in the EC group (P = 0.29), however, VAS scores for CO₂ insufflation were significantly better than air insufflation in the LEC group (P = 0.023) immediately after colonoscopies and up to 4 h afterwards.

CONCLUSION: CO₂ insufflation reduced patient pain after colonoscopy in potentially difficult cases when performed by LECs.

Novel chromoendoscopic method using an acetic acid-indigocarmine mixture for diagnostic accuracy in delineating the margin of early gastric cancers

BACKGROUND AND AIM

Recent endoscopic imaging techniques for recognition of unclear lesions in the stomach (e.g. narrow band imaging, magnifying endoscopy) require special equipment and therefore are not commonly used. The aim of the present study was to estimate the accuracy of a new chromoendoscopic method using an acetic acid-indigo carmine mixture (AIM) in diagnosing early gastric cancers (EGC).

METHODS

Studied were 108 EGC lesions in 104 patients. EGC were initially observed by white light (WL) after which indigo carmine (IC) solution was sprinkled onto the gastric mucosa. Images by WL and IC observation were recorded by a digital filing system. After washing away IC solution with water, AIM solution was sprinkled onto the gastric mucosa and images were recorded. Margin lines of EGC determined by each observation were drawn on recorded images by graphic software for comparison with resected specimens. After lines were similarly drawn on images of resected specimens, the extent of the lesions was compared with that determined by endoscopic images.

RESULTS

Diagnostic accuracy of WL, IC, and AIM observations were 50.0%, 75.9% and 90.7%, respectively. No adverse events occurred with the AIM method.

CONCLUSIONS

This chromoendoscopic method can be used to delineate the margin of EGC accurately, easily, safely and inexpensively.

Risk factors associated with local recurrence of early gastric cancers after endoscopic submucosal dissection

BACKGROUND

Although endoscopic submucosal dissection (ESD) is expected to reduce the local recurrence of gastric cancers, we still experience cases of recurrence after an ESD.

OBJECTIVE

To characterize clinical and pathologic features of cases with local recurrence of early gastric cancer after an ESD.

DESIGN

A prospective cohort study.

SETTING AND PATIENTS

A total of 306 patients with gastric cancers removed by ESD at Okayama University Hospital and Tsuyama Central Hospital between March 2001 and December 2005 were enrolled.

INTERVENTION

ESD.

MAIN OUTCOME MEASUREMENT

Local recurrence.

RESULTS

The incidence of a complete en bloc resection was 80.4% when pathologically evaluated. Within a median follow-up period of 26 months (12-64 months), a local recurrence was found in 7 cases, all of which had been declared incomplete resections. One patient underwent a second ESD, and the remaining 6 underwent a surgical resection. All removed lesions were mucosal cancers. No lymph-node metastases were found in patients with a surgical resection. There was a significant correlation between the incidence of an incomplete resection and that of a local recurrence (P < .0001). Among the clinical characteristics, tumor size (>30 mm vs <20 mm; odds ratio [OR] 16 mm [95% CI, 2.0-130 mm]) and tumor location (upper vs middle or lower; OR 7.6 [95% CI, 1.3-45]) were identified as factors that were significantly associated with the incidence of a local recurrence.

LIMITATION

Short follow-up duration.

CONCLUSIONS

The incidence of a local recurrence was strongly associated with that of an incomplete resection. The frequency of a local recurrence also showed significant correlations with the tumor size and location within the stomach.

Novel QTLs for photoperiodic flowering revealed by using reciprocal backcross inbred lines from crosses between japonica rice cultivars

The rice japonica cultivars Nipponbare and Koshihikari differ in heading date and response of heading to photoperiod (photoperiod sensitivity). Using simple sequence repeat (SSR) and single nucleotide polymorphism (SNP) markers, we conducted quantitative trait locus (QTL) analyses for heading date in a set of reciprocal backcross inbred lines (BILs) from crosses between Nipponbare and Koshihikari. Under natural-day conditions, transgressive segregation in days to heading (DTH) toward both early and late heading was observed in both BIL populations. QTL analyses revealed that two QTLs--on chromosomes 3 and 6--were involved in the difference in heading date between the parental cultivars. The Nipponbare allele at the QTLs on chromosomes 3 and 6 showed, respectively, increasing and decreasing effects on DTH in both BIL populations. The transgressive segregation observed in the BILs could be accounted for mainly by the complementary action of a set of alleles with opposing effects. Both QTLs were finely mapped as single Mendelian factors in secondary mapping populations (BC2F2 plants/BC2F3 lines). The QTL on chromosome 3 was mapped in the 1,140-kb interval between 94O03-4 (SSR) and OJ21G19-4 (SNP) and was designated Hd16. The QTL on chromosome 6 was mapped in the 328-kb interval between P548D347 (SSR) and 0007O20 (SSR) and was designated Hd17. Both Hd16 and Hd17 were involved in photoperiod sensitivity, as revealed by observation of the DTH of nearly isogenic lines of Nipponbare under short- and long-day conditions, suggesting that allelic differences in both Hd16 and Hd17 account for most of the difference in photoperiod sensitivity between the parental cultivars.

Interobserver agreement in endoscopic evaluation of reflux esophagitis using a modified Los Angeles classification incorporating grades N and M: a validation study in a cohort of Japanese endoscopists

The Los Angeles classification system is the most widely employed criteria associated with the greatest interobserver agreement among endoscopists. In Japan, the Los Angeles classification system has been modified (modified LA system) to include minimal changes as a distinct grade of reflux esophagitis, rather than as auxiliary findings. This adds a further grading M defined as minimal changes to the mucosa, such as erythema and/or whitish turbidity. The modified LA system has come to be used widely in Japan. However, there have been few reports to date that have evaluated the interobserver agreement in diagnosis when using the modified LA classification system incorporating these minimal changes as an additional grade. A total of 100 endoscopists from university hospitals and community hospitals, as well as private practices in the Osaka-Kobe area participated in the study. A total of 30 video clips of 30-40 seconds duration, mostly showing the esophagocardiac junction, were created and shown to 100 endoscopists using a video projector. The participating endoscopists completed a questionnaire regarding their clinical experience and rated the reflux esophagitis as shown in the video clips using the modified LA classification system. Agreement was assessed employing kappa (kappa) statistics for multiple raters. The kappa-value for all 91 endoscopists was 0.094, with a standard error of 0.002, indicating poor interobserver agreement. The endoscopists showed the best agreement on diagnosing grade A esophagitis (0.167), and the poorest agreement when diagnosing grade M esophagitis (0.033). The kappa-values for the diagnoses of grades N, M, and A esophagitis on identical video pairs were 0.275-0.315, with a standard error of 0.083-0.091, indicating fair intraobserver reproducibility among the endoscopists. The study results consistently indicate poor agreement regarding diagnoses as well as fair reproducibility of these diagnoses by endoscopists using the modified LA classification system, regardless of age, type of practice, past endoscopic experience, or current workload. However, grade M reflux esophagitis may not necessarily be irrelevant, as it may suggest an early form of reflux disease or an entirely new form of reflux esophagitis. Further research is required to elucidate the pathophysiological basis of minimal change esophagitis.

Asymptomatic disseminated carcinomatosis of bone marrow presenting as hyperphosphatasia: report of a case

Metastatic involvement of the musculoskeletal system is one of the most significant clinical issues facing orthopaedic oncologists. The number of patients with metastasis to the skeletal system from a carcinoma is 15 times greater than the number of patients with primary bone tumours of all types. However, progression patterns like disseminated carcinomatosis of bone marrow are comparatively rare. The pathophysiology for disseminated carcinomatosis of bone marrow, with a prognosis reported to be very poor, is still unknown. We describe a patient who had no symptoms with hyperphosphatasia. Bone scintigraphy showed a so-called super bone scan and a needle biopsy from the ileum showed adenocarcinoma cells. Additional endoscopic investigation was performed and signet cell gastric cancer was found. From the bone scan and biopsy, we established the diagnosis of disseminated carcinomatosis of the bone marrow. From the experience of this case, we believe that intensive stomach investigation should be considered in cases with hyperphosphatasia, even when the patient has no symptoms.

Apparent diffusion coefficient of pituitary macroadenoma evaluated with line-scan diffusion-weighted imaging

OBJECTIVE

The goal of this study was to evaluate the consistency of pituitary macroadenoma using apparent diffusion coefficient (ADC) with line-scan diffusion-weighted imaging (LSDWI).

METHODS

Patients with pituitary macroadenoma (n=19) were studied prospectively. The LSDWI was performed using a maximum b factor of 1000 s/mm2. The consistency of macroadenoma was rated as soft, intermediate or hard at transsphenoidal surgery. The ADC values of tumors were compared with the tumor-consistency ratings.

RESULTS

A soft consistency was found at surgery in 13 patients (mean ADC: 0.84+/-0.1x10(-3) mm2/s); an intermediate consistency was observed in six patients (mean ADC: 0.81+/-0.16x10(-3) mm2/s). No tumors of hard consistency were found. There was no significant difference in ADC values between tumors of soft consistency compared with tumors of intermediate consistency (P=0.37).

CONCLUSIONS

A relationship between tumor consistency and the ADCs of soft and intermediate macroadenomas was not shown in this study using LSDWI.

A software environment for simulators suitable for complex biological analysis

In order to understand the function of biological elements and their interactions, computer analysis and simulation is an essential technique. For higher research efficiency, it is important to provide a system framework for constructing biological simulation systems that handle multiple phenomena. This paper proposes "DynaBioS", a comprehensive system framework for complex biological simulations. This framework consists of three main features, a component-based architecture, a customizable system operation, and an exchangeable model set. The system based on DynaBioS consists of a simulation core and system components. The system components are sub-simulators for individual functional factors and utility modules corresponding to specific information technologies. The simulation core manages and controls all components, in accordance with a simulation scenario and a simulation model. The DynaBioS makes it possible to implement different simulation systems by combining individual functional components, specific interactions and different simulation models. The versatility of DynaBioS is shown by two examples, a heart pumping simulator and a parameter optimization system for physiological models.

Association between IL-18 gene promoter polymorphisms and inflammatory bowel disease in a Japanese population

BACKGROUND

Interleukin-18 (IL-18) is a pleiotropic cytokine that induces the production of interferon (IFN)-gamma and also to regulate Th2 cytokines. Recently, association studies between IL-18 gene promoter polymorphisms and several Th1- or Th2-mediated inflammatory diseases were reported. In inflammatory bowel diseases (IBD), including ulcerative colitis (UC) and Crohn's disease (CD), recent evidence suggests that IL-18 is involved in the pathogenesis.

METHODS

Using DNA direct sequencing, we investigated IL-18 gene promoter polymorphisms at -607C/A and -137G/C. Allele, genotype, and haplotype frequencies were determined in 210 Japanese patients with UC, 205 patients with CD, and 212 controls.

RESULTS

In UC, the -137C allele frequency was significantly higher in the proctitis-type patients than in controls (Pc = 0.0068). The -137 genotype frequency was also significantly different in the proctitis-type patients than in controls (Pc = 0.032). No other allele and genotype frequencies were significantly associated with UC after Bonferroni correction. Furthermore, the frequency of haplotype 2 (-607A, -137C), which had a lower promoter activity and IFN-gamma mRNA level than the other haplotypes as previously reported, was significantly higher in the proctitis-type patients than in controls (Pc = 0.01). In CD, we could not find any significant differences.

CONCLUSIONS

IL-18 gene promoter polymorphisms may not be associated with disease susceptibility but related to the extent of disease in UC.

QTL analysis of Fusarium head blight resistance using a high-density linkage map in barley

Fusarium head blight (FHB) resistance was evaluated in a set of recombinant inbred (RI) lines from a cross between Russia 6 (resistant) and H.E.S. 4 (susceptible), which had one of the widest differences of FHB resistance reactions among ca. 5,000 barley germplasm accessions in Okayama University. Field-grown spikes were sampled and inoculated by the 'cut-spike test'. Resistance reactions on the parents and RI lines were scored by eleven grades, from resistant (0) to susceptible (10). Quantitative trait loci (QTL) analysis detected three QTL: two located on the long arm of chromosome 2H, and another on the short arm of chromosome 5H. A QTL located on chromosome 2H was coincident with the vrs1 locus, which governs inflorescence row type. The other QTL on chromosome 2H was positioned in the vicinity of cleistogamy locus (cly1 or Cly2) that determines inflorescence opening/closing. Resistant gene analog (RGA) and expressed sequence tag (EST) markers with homology for disease resistance genes were integrated into the high-density linkage map. Most of these markers were not localized near the identified resistance QTL, except for one RGA marker (FXLRRfor_XLRRrev170) localized in the vicinity of the cly1/Cly2 locus. Five AFLP markers localized in the vicinity of the identified QTL were sequenced to convert them into sequence tagged site (STS) markers. Genotyping of each RI line using two AFLP-STS markers and the vrs1 locus indicated that the RI lines with three Russia 6 QTL alleles exhibited the same level of high FHB resistance reactions as Russia 6. In contrast, RI lines with three susceptible alleles showed reactions close to H.E.S. 4. Therefore, the markers closely linked to the QTL can be efficiently used for the selection of resistance.

Resolution of primary amyloidosis by melphalan and prednisolone: a case report

We here report a case of a 50-year-old man who showed histologically evident resolution of primary amyloidosis by melphalan and prednisolone. The patient was admitted to our hospital for further evaluation of nephrotic syndrome and remarkable hepatomegaly with refractory ascites, on September 11, 1998. Laboratory tests at presentation showed nephrotic syndrome with slight renal impairment and elevation of the enzymes of the biliary system. Monoclonal light chains were not detected in the serum or urine by immunoelectrophoresis. A renal biopsy revealed global deposition of amyloid in all glomeruli, interstitium and blood vessels. Immunofluorescence staining was positive for kappa light chains. Liver biopsy specimens showed extensive deposition of amyloid along sinusoid walls. Bone marrow aspiration contained 7% plasma cells but no clusters or abnormal cells. Based on these findings, systemic AL- (amyloid light chain) amyloidosis was diagnosed, and the treatment with combinations of melphalan and prednisolone was started from October 1998 at intervals of 4-6 weeks. Renal impairment progressed, resulting in the initiation of maintenance hemodialysis in February 1999. Reinfusion of ascitic fluid into the hemodialysis circuit had been performed from March 1999 for refractory ascites, and ascites disappeared in July 1999. Furthermore, urinary output increased after 14 courses of chemotherapy. Renal function gradually ameliorated with a concomitant reduction in the enzymes of biliary system, and finally hemodialysis was discontinued in April 2001. Sixteen courses of chemotherapy were administered by April 2001. Proteinuria was negative in August 2001. A second renal biopsy was performed on November 20, 2001, which showed markedly decreased amyloid deposition and a proliferation of mesangial cells and increase in matrix in various degrees. We report a case of a patient with primary amyloidosis who was successfully treated by melphalan and prednisolone, resulting in marked resolution of renal amyloidosis.

Dynamics of airborne pollen particles from inhalation to allergic reaction in the nose

BACKGROUND

Pollinosis is common worldwide, and has been frequently studied. However, the intranasal dynamics of pollen grains have not yet been documented. The purpose of this study is to elucidate for the first time the dynamics of Japanese cedar pollen (JCP) in the human nose at consecutive steps from inhalation to allergic reaction together with release of Cry j 1 (a major allergenic component of JCP) in the nose.

METHODS

A personal sampler collected airborne pollens at head height outdoor on the street, while intranasal pollens after natural or experimental inhalation were collected by irrigation with 200ml saline. Cry j 1 in the supernatant after in vitro incubation with phosphate buffered saline or lavage was determined by enzyme-linked immunoassay.

RESULTS

Head-height pollen was 183.0 +/- 43.1/300L/h, with 99% of the inhaled pollens deposited on the nasal surface. Eighty eight% of the inhaled pollen was transported to the out-side of the nose by ciliary function within 3 hours. During this process, considerable amounts of Cry j 1 were released in the nose reaching its plateau within 30 min. When the number of pollen deposited exceeded more than approximately 65 particles, symptoms may occur, leading presumably up to a 74% reduction of the intra-nasal pollen.

CONCLUSION

The majority of inhaled airborne pollens was deposited on the nasal mucosal surface and moved out from the nose by mucociliary transportation. During this process, when allergenic substances are released up to a critical concentration, allergic reactions occur leading to expelling of pollen from the nose followed by subsiding of the symptoms.

Hippocalcin-deficient mice display a defect in cAMP response element-binding protein activation associated with impaired spatial and associative memory

Hippocalcin is a member of the neuronal calcium sensor (NCS) protein family that is highly expressed in hippocampal pyramidal cells and moderately expressed in the neurons of cerebral cortex, cerebellum and striatum. Here we examined the physiological roles of hippocalcin using targeted gene disruption. Hippocalcin-deficient (-/-) mice displayed no obvious structural abnormalities in the brain including hippocampal formation at the light microscopic level. Deletion of hippocalcin did not result in up-regulation of the hippocalcin-related proteins; neural visinin-like Ca(2+)-binding proteins (NVP) 1, 2, and 3. The synaptic excitability of hippocampal CA1 neurons appeared to be normal, as estimated by the shape of field excitatory postsynaptic potentials elicited by single- and paired-pulse stimuli, and by tetanic stimulation. However, N-methyl-d-aspartate stimulation- and depolarization-induced phosphorylation of cAMP-response element-binding protein (CREB) was significantly attenuated in -/- hippocampal neurons, suggesting an impairment in an activity-dependent gene expression cascade. In the Morris water maze test, the performance of -/- mice was comparable to that of wild-type littermates except in the probe test, where -/- mice crossed the previous location of the platform significantly less often than +/+ mice. Hippocalcin-deficient mice were also impaired on a discrimination learning task in which they needed to respond to a lamp illuminated on the left or right side to obtain food reinforcement. No abnormalities were observed in motor activity, anxiety behavior, or fear learning. These results suggest that hippocalcin plays a crucial role in the Ca(2+)-signaling pathway that underlies long-lasting neural plasticity and that leads to spatial and associative memory.

High fidelity SNP genotyping using sequence-specific primer elongation and fluorescence correlation spectroscopy

Reliable, efficient and cost-effective modalities are urgently needed for mass screening of gene mutations. Previous reports have shown that SSCP or genechip methods require substantial time and monetary costs, thus limiting their appeal. Sequence Specific Primer Polymerase Chain Reaction (SSP-PCR) is a reliable and cost-effective method that utilizes the 3'-end discrimination properties of polymerase. However, the applicability of conventional SSP-PCR is limited due to the difficulties associated with determining optimal conditions and because mis-matched primers are amplified, resulting in signal noise during end-point assay. To overcome this problem, we eliminated the reverse primers from SSP-PCR, thus preventing amplification of mis-matched primers. We designated this method Sequence-Specific Primer Cycle Elongation (SSPCE). However, the detection of elongated sequence specific primers was difficult using conventional electrophoresis due to the small amounts of amplification product present. We therefore combined SSPCE and Fluorescence Correlation Spectroscopy, which is a novel technique used to determine the number and size of fluorophores at nano-molar concentrations, and designated the method SSPCE-FCS. We compared conventional SSP-PCR and SSPCE-FCS with regard to determining optimal conditions using two Mitochondrial SNPs (G --> A at position 1598, G --> A at position 12192). We were able to determine the optimal conditions for the SNP at position 1598 using either method. However, optimal conditions could only be determined for SSPCE-FCS with the 12192 mutation because non-specific amplification was observed at a wide range of annealing temperatures in SSP-PCR. We then applied this method to three other SNPs and the results were consistent with the results of sequencing data.