Reducing the number of accepted species in Aspergillus series Nigri

The Aspergillus series Nigri contains biotechnologically and medically important species. They can produce hazardous mycotoxins, which is relevant due to the frequent occurrence of these species on foodstuffs and in the indoor environment. The taxonomy of the series has undergone numerous rearrangements, and currently, there are 14 species accepted in the series, most of which are considered cryptic. Species-level identifications are, however, problematic or impossible for many isolates even when using DNA sequencing or MALDI-TOF mass spectrometry, indicating a possible problem in the definition of species limits or the presence of undescribed species diversity. To re-examine the species boundaries, we collected DNA sequences from three phylogenetic markers (benA, CaM and RPB2) for 276 strains from series Nigri and generated 18 new whole-genome sequences. With the three-gene dataset, we employed phylogenetic methods based on the multispecies coalescence model, including four single-locus methods (GMYC, bGMYC, PTP and bPTP) and one multilocus method (STACEY). From a total of 15 methods and their various settings, 11 supported the recognition of only three species corresponding to the three main phylogenetic lineages: A. niger, A. tubingensis and A. brasiliensis. Similarly, recognition of these three species was supported by the GCPSR approach (Genealogical Concordance Phylogenetic Species Recognition) and analysis in DELINEATE software. We also showed that the phylogeny based on benA, CaM and RPB2 is suboptimal and displays significant differences from a phylogeny constructed using 5 752 single-copy orthologous proteins; therefore, the results of the delimitation methods may be subject to a higher than usual level of uncertainty. To overcome this, we randomly selected 200 genes from these genomes and performed ten independent STACEY analyses, each with 20 genes. All analyses supported the recognition of only one species in the A. niger and A. brasiliensis lineages, while one to four species were inconsistently delimited in the A. tubingensis lineage. After considering all of these results and their practical implications, we propose that the revised series Nigri includes six species: A. brasiliensis, A. eucalypticola, A. luchuensis (syn. A. piperis), A. niger (syn. A. vinaceus and A. welwitschiae), A. tubingensis (syn. A. chiangmaiensis, A. costaricensis, A. neoniger and A. pseudopiperis) and A. vadensis. We also showed that the intraspecific genetic variability in the redefined A. niger and A. tubingensis does not deviate from that commonly found in other aspergilli. We supplemented the study with a list of accepted species, synonyms and unresolved names, some of which may threaten the stability of the current taxonomy. Citation: Bian C, Kusuya Y, Sklenář F, D'hooge E, Yaguchi T, Ban S, Visagie CM, Houbraken J, Takahashi H, Hubka V (2022). Reducing the number of accepted species in Aspergillus series Nigri. Studies in Mycology 102: 95-132. doi: 10.3114/sim.2022.102.03.

Monkeypox Vaccination in the Republic of Korea: Identifying the High-Risk Target Group

In June 2022, the first monkeypox case was reported as imported into Korea. The general public asked whether they should get vaccinated against monkeypox because of the recent COVID-19 vaccination experience. As of the current monkeypox outbreak situation, a ring vaccination strategy for the high-risk group is more appropriate than the mass population vaccination with smallpox vaccines. Therefore, identifying the proper target group by available vaccines based on the risk and benefit analysis is a key issue of the vaccination program. In addition, the target group should be reviewed by the epidemiological situation of the jurisdiction along with the updated evidence of the monkeypox virus on transmission dynamics, severity, and fatality.

Search for Electron Antineutrino Appearance in a Long-Baseline Muon Antineutrino Beam

Electron antineutrino appearance is measured by the T2K experiment in an accelerator-produced antineutrino beam, using additional neutrino beam operation to constrain parameters of the Pontecorvo-Maki-Nakagawa-Sakata (PMNS) mixing matrix. T2K observes 15 candidate electron antineutrino events with a background expectation of 9.3 events. Including information from the kinematic distribution of observed events, the hypothesis of no electron antineutrino appearance is disfavored with a significance of 2.40σ and no discrepancy between data and PMNS predictions is found. A complementary analysis that introduces an additional free parameter which allows non-PMNS values of electron neutrino and antineutrino appearance also finds no discrepancy between data and PMNS predictions.

Predicting the Debonding of CAD/CAM Composite Resin Crowns with AI

A preventive measure for debonding has not been established and is highly desirable to improve the survival rate of computer-aided design/computer-aided manufacturing (CAD/CAM) composite resin (CR) crowns. The aim of this study was to assess the usefulness of deep learning with a convolution neural network (CNN) method to predict the debonding probability of CAD/CAM CR crowns from 2-dimensional images captured from 3-dimensional (3D) stereolithography models of a die scanned by a 3D oral scanner. All cases of CAD/CAM CR crowns were manufactured from April 2014 to November 2015 at the Division of Prosthodontics, Osaka University Dental Hospital (Ethical Review Board at Osaka University, approval H27-E11). The data set consisted of a total of 24 cases: 12 trouble-free and 12 debonding as known labels. A total of 8,640 images were randomly divided into 6,480 training and validation images and 2,160 test images. Deep learning with a CNN method was conducted to develop a learning model to predict the debonding probability. The prediction accuracy, precision, recall, F-measure, receiver operating characteristic, and area under the curve of the learning model were assessed for the test images. Also, the mean calculation time was measured during the prediction for the test images. The prediction accuracy, precision, recall, and F-measure values of deep learning with a CNN method for the prediction of the debonding probability were 98.5%, 97.0%, 100%, and 0.985, respectively. The mean calculation time was 2 ms/step for 2,160 test images. The area under the curve was 0.998. Artificial intelligence (AI) technology-that is, the deep learning with a CNN method established in this study-demonstrated considerably good performance in terms of predicting the debonding probability of a CAD/CAM CR crown with 3D stereolithography models of a die scanned from patients.

Search for CP Violation in Neutrino and Antineutrino Oscillations by the T2K Experiment with 2.2×10^{21} Protons on Target

The T2K experiment measures muon neutrino disappearance and electron neutrino appearance in accelerator-produced neutrino and antineutrino beams. With an exposure of 14.7(7.6)×10^{20} protons on target in the neutrino (antineutrino) mode, 89 ν_{e} candidates and seven anti-ν_{e} candidates are observed, while 67.5 and 9.0 are expected for δ_{CP}=0 and normal mass ordering. The obtained 2σ confidence interval for the CP-violating phase, δ_{CP}, does not include the CP-conserving cases (δ_{CP}=0, π). The best-fit values of other parameters are sin^{2}θ_{23}=0.526_{-0.036}^{+0.032} and Δm_{32}^{2}=2.463_{-0.070}^{+0.071}×10^{-3}  eV^{2}/c^{4}.

[How Does Advance Provision of Emergency Contraceptives Affect Contraceptive Use and Sexual Activity Among Adolescents? Systematic Review and Meta-Analysis]

PURPOSE

The purpose of this study was to analyze the effect of emergency contraceptive pill on adolescent sexuality and contraceptive behaviors through a meta - analysis of intervention studies on advance provision of emergency contraceptives. This study aimed to provide objective data on the transition of general medicines to be discussed in relation to the reclassification of emergency contraceptive pills.

METHODS

Using electronic database, 1,820 studies written in Korean or English without limitation of the year were reviewed and for analysis, 5 studies were selected, in which emergency contraceptives were provided to adolescents.

RESULTS

The advance provision of emergency contraceptives has increased their use and shortened the time it takes to take contraceptive pills after unprotected sex. There was no change in the frequency of engaging in sexual intercourse and unprotected sex or in existing contraceptive behavior, pregnancy rates decreased, but there was no increase in sexually transmitted infection.

CONCLUSION

The results of this study provide objective grounds for the reclassification of emergency contraceptive pills and propose effective interventional programs on contraceptive education, such as on efficacy and side effects of the contraceptive drug and its proper use among the youth who engage in sexual activity, to improve their reproductive health.

Combined Analysis of Neutrino and Antineutrino Oscillations at T2K

T2K reports its first results in the search for CP violation in neutrino oscillations using appearance and disappearance channels for neutrino- and antineutrino-mode beams. The data include all runs from January 2010 to May 2016 and comprise 7.482×10^{20} protons on target in neutrino mode, which yielded in the far detector 32 e-like and 135  μ-like events, and 7.471×10^{20} protons on target in antineutrino mode, which yielded 4 e-like and 66  μ-like events. Reactor measurements of sin^{2}2θ_{13} have been used as an additional constraint. The one-dimensional confidence interval at 90% for the phase δ_{CP} spans the range (-3.13, -0.39) for normal mass ordering. The CP conservation hypothesis (δ_{CP}=0, π) is excluded at 90% C.L.

Measurement of Coherent π^{+} Production in Low Energy Neutrino-Carbon Scattering

We report the first measurement of the flux-averaged cross section for charged current coherent π^{+} production on carbon for neutrino energies less than 1.5 GeV, and with a restriction on the final state phase space volume in the T2K near detector, ND280. Comparisons are made with predictions from the Rein-Sehgal coherent production model and the model by Alvarez-Ruso et al., the latter representing the first implementation of an instance of the new class of microscopic coherent models in a neutrino interaction Monte Carlo event generator. We observe a clear event excess above background, disagreeing with the null results reported by K2K and SciBooNE in a similar neutrino energy region. The measured flux-averaged cross sections are below those predicted by both the Rein-Sehgal and Alvarez-Ruso et al.

Computing the Heat of Adsorption using Molecular Simulations: The Effect of Strong Coulombic Interactions

Molecular simulations are an important tool for the study of adsorption of hydrocarbons in nanoporous materials such as zeolites. The heat of adsorption is an important thermodynamic quantity that can be measured both in experiments and molecular simulations, and therefore it is often used to investigate the quality of a force field for a certain guest-host (g - h) system. In molecular simulations, the heat of adsorption in zeolites is often computed using either of the following methods: (1) using the Clausius-Clapeyron equation, which requires the partial derivative of the pressure with respect to temperature at constant loading, (2) using the energy difference between the host with and without a single guest molecule present, and (3) from energy/particle fluctuations in the grand-canonical ensemble. To calculate the heat of adsorption from experiments (besides direct calorimetry), only the first method is usually applicable. Although the computation of the heat of adsorption is straightforward for all-silica zeolites, severe difficulties arise when applying the conventional methods to systems with nonframework cations present. The reason for this is that these nonframework cations have very strong Coulombic interactions with the zeolite. We will present an alternative method based on biased interactions of guest molecules that suffers less from these difficulties. This method requires only a single simulation of the host structure. In addition, we will review some of the other important issues concerning the handling of these strong Coulombic interactions in simulating the adsorption of guest molecules. It turns out that the recently proposed Wolf method ( J. Chem. Phys. 1999, 110 , 8254 ) performs poorly for zeolites as a large cutoff radius is needed for convergence.

Analysis of the effect of structural materials in a wall-less tissue-equivalent proportional counter irradiated by 290 MeV u(-1) carbon beam

Effects of structural materials in a wall-less tissue-equivalent proportional counter were evaluated based on the calculation of energy deposits by EGS5 and the measurement of lineal energy distributions using 290 MeV u(-1) carbon beams. It is found that the correction of measured data based on simulation is necessary for understanding the energy deposition spectra in the homogeneous condition in tissues.

Competitive coexistence of superconductivity with antiferromagnetism in CeRhIn5

We carried out ac magnetic susceptibility measurements under pressures P on the heavy fermion antiferromagnet CeRhIn5. We report bulk superconductivity (SC) at ambient pressure with a transition temperature Tc approximately or equal to 90 mK. The degraded SC in a powdered or polished sample was restored by annealing, showing that the SC state is sensitive to inhomogeneity. In a coexistence region of the SC with antiferromagnetism (AF), we find that Tc(P)(n)TN(P)(1-n) = const where TN indicates a Néel temperature and n denotes a ratio of electronic specific heat coefficients below and above TN, indicating the competition of the SC and the AF for states at the Fermi surface.

Venepuncture is preferable to heel lance for blood sampling in term neonates

BACKGROUND

The analgesic effect of oral sucrose in newborn infants undergoing painful procedures is generally accepted. For blood sampling, some studies have shown that venepuncture (VP) is less painful than heel lance (HL).

OBJECTIVE

To determine the least painful and most effective method among blood sampling by VP or HL with or without sucrose.

DESIGN

Randomised, double blind, placebo controlled trial.

SUBJECTS

A total of 100 healthy, full term newborn infants being screened for inborn errors of metabolism were randomly allocated to one of four experimental groups (25 infants in each). Intervention and

OUTCOME MEASURE

Seven specially trained nurses took turns to carry out blood sampling two minutes after administration of oral sucrose or water. Neonatal pain was assessed by the neonatal facial coding system (NFCS), as well as by crying.

RESULTS

Without sucrose, the NFCS score was higher in the HL group than the VP group during blood sampling (median 58 v 23, p<0.001). Oral sucrose significantly reduced the score of the HL group (58 v 47, p<0.01) and also tended to reduce the score of the VP group (23 v 2, p<0.1). However, the HL with sucrose group still had a higher score than the VP without sucrose group (47 v 23, p<0.01). Crying and the total procedure time showed the same trends as the NFCS score.

CONCLUSIONS

VP is less painful and more effective than HL for blood sampling in newborn infants. Although oral sucrose may have an additive analgesic effect, it is not necessarily required if VP is used for blood sampling.

Arrangement of high-energy neutron irradiation field and shielding experiment using 4 m concrete at KENS

An irradiation field of high-energy neutrons produced in the forward direction from a thick tungsten target bombarded by 500 MeV protons was arranged at the KENS spallation neutron source facility. In this facility, shielding experiment was performed with an ordinary concrete shield of 4 m thickness assembled in the irradiation room, 2.5 m downstream from the target centre. Activation detectors of bismuth, aluminium, indium and gold were inserted into eight slots inside the shield and attenuations of neutron reaction rates were obtained by measurements of gamma-rays from the activation detectors. A MARS14 Monte Carlo simulation was also performed down to thermal energy, and comparisons between the calculations and measurements show agreements within a factor of 3. This neutron field is useful for studies of shielding, activation and radiation damage of materials for high-energy neutrons, and experimental data are useful to check the accuracies of the transmission and activation calculation codes.

Expression of cyclooxygenase-2 in human hyperplastic gastric polyps

Cyclooxygenase (COX)-2, an inducible isoform of prostaglandin synthetase, has been reported to be a key molecular target of colon cancer prevention by nonsteroidal anti-inflammatory drugs. Recently, it has been shown that Helicobacter pylori (H. pylori) could induce COX-2 together with inflammatory cytokines. Although human hyperplastic gastric polyps disappeared or decreased in number and size after eradication of H. pylori, the mechanisms in this step, especially the roles of COX-2, have not been yet elucidated. The aims of the present study were to examine the expression and localization of COX-2 in human hyperplastic gastric polyps immunohistochemically. Twelve specimens of human hyperplastic gastric polyps were obtained from endoscopic polypectomy. The expression of the COX-2 protein was immunohistochemically examined on formalin-fixed and paraffin-embedded tissue sections using an anti-COX-2 antibody and an avidin-biotin complex method. Cells expressing COX-2 were further immunohistochemically identified using a specific antibody against macrophages (CD68), and myofibroblasts (alpha-smooth muscle actin). Immunoreactive COX-2 was predominantly and strongly expressed in interstitial cells in the sub-epithelial layer of 10 hyperplastic polyps. Semi-quantitative analysis revealed a significant increase in COX-2 expression in interstitial cells. The staining pattern of macrophages and myofibroblasts partly corresponded to that observed for COX-2 in hyperplastic gastric polyps. These results suggest that COX-2 in mesenchymal cells induced by H. pylori may play an important role in the tumorigenesis of human hyperplastic gastric polyps.

Chromosomal instability and radiosensitivity in myelodysplastic syndrome cells

Myelodysplastic syndrome (MDS) is a clonal disorder of hematopoietic stem cells. To investigate whether chromosomal instability and/or DNA repair defects are involved in the development of MDS, we measured the micronucleus (MN) frequency in peripheral blood lymphocytes exposed to various doses of X-rays, using a cytokinesis-block micronucleus assay. The spontaneous MN frequencies in RAEB and RAEB-T patients were significantly higher than those in normal individuals (P = 0.0224, P = 0.008, respectively). Also, the X-ray-induced MN frequencies in RA/RARS, RAEB, and RAEB-T patients were significantly higher than those in normal individuals (P = 0.007, P = 0.003, P = 0.003, respectively, at 2 Gy). In order to elucidate the cause of unusual radiosensitivity, we measured the expression levels of nucleotide excision repair (NER) genes in peripheral blood mononuclear cells using a RT-PCR method. Reduction of NER gene expression was found in only one of 10 patients with low risk MDS, but in four of 11 patients with high risk MDS. Our data suggest that chromosomal instability and DNA repair defects may be involved in the pathophysiology of disease progression of MDS.

Change in cytoskeletal phenotype and extracellular matrix production of muscularis mucosae during early invasive colorectal adenocarcinoma

Bundles of eosinophilic spindle cells are often found in histological preparations of the stroma of invasive colorectal adenocarcinomas. To clarify their significance, especially during the early invasive phase, we histologically and immunohistochemically studied 33 submucosally invasive colorectal adenocarcinomas in terms of their relationship with the muscularis mucosa, their cytoskeletal phenotype, and their production of extracellular matrix (ECM). Histological continuity between bundles of eosinophilic spindle cells and the muscularis mucosa was identified in 19 out of 33 adenocarcinomas (57.6%). With respect to their cytoskeletal phenotypes, the expression of alpha-smooth muscle actin (alpha-SMA) did not differ between the muscularis mucosa and the eosinophilic spindle cells, whereas the expression of desmin and high molecular weight caldesmon (h-CD) of the eosinophilic spindle cells was decreased compared with that of the muscularis mucosa (p<0.05). Definitive type I procollagen (procollagen I) expression was identified, at least in part, in 16 out of 20 (80%) areas of the eosinophilic spindle cells that were continuous with the muscularis mucosa, and in 26 out of 29 (89.7%) areas of the eosinophilic spindle cells that were not. These findings suggest that the muscularis mucosa is the origin of the eosinophilic spindle cells, that they undergo phenotypic changes separately from the smooth muscle, that is, myofibroblastic changes, and that they contribute to carcinomatous stroma formation through production of an ECM component. These findings should be taken into consideration when determining the level of submucosal invasion by colorectal adenocarcinomas.

Response of GafChromic MD-55 radiochromic film to synchrotron radiation

Synchrotron radiation has been increasingly and extensively used for materials science, biology and medical research. For measurement of high dose from the low energy photons, tissue-equivalent dosemeters having linearity in the Gy region are required. In this study, energy and dose responses of double-layer Gafchromic film MD-55 were measured using 10-40 keV monoenergetic photons from synchrotron radiation. The result showed that the energy responses normalised at 60Co gamma rays were 0.58-0.59 at 10-20 keV, 0.66 at 30 keV and 0.72 at 40 keV in air. The linearity was confirmed to extend from 2 Gy to 100 Gy.

Modification of electrochemically deposited apatite using supercritical water

Supercritical water was used as a modification method of electrochemically deposited apatite on pure titanium. The apatites were coated on a commercially pure titanium plate using a hydrothermal-electrochemical method. A constant direct current at 12.5 mA/cm2 was loaded for 1 hr at 25, 60, 100, 150 and 200 degrees C in an electrolyte containing calcium and phosphate ions. The deposited apatite on the titanium substrate was stored in supercritical water at 450 degrees C under 45 MPa for 8 hr. With this treatment, the crystallinity of the apatites increased, sharp edges of the deposited apatites were rounded off, and the bonding strength of the titanium substrate to the deposited apatites significantly increased. On the other hand, weight loss in 0.01 N HCl decreased and the weight gain rate in a simulated body fluid also decreased with this treatment. It is suggested that the modification using supercritical water improved the mechanical strength of the deposited apatite, but worsened its bioactivity.

Establishment of a testicular carcinoma cell line producing alpha-fetoprotein

OBJECTIVE

To characterize a newly established human testicular carcinoma cell line that continuously produces alpha-fetoprotein (AFP), and to investigate the effects of retinoic acid on AFP production.

MATERIALS AND METHODS

A 24-year-old man underwent a radical orchidectomy for a right testicular tumour and was found to have two separate metastatic lesions in the lungs, both of which were removed surgically. The cancer cells were isolated from one of the tumours, which was composed of undifferentiated germ cells and produced AFP; the cells were cultured in a monolayer. This cell line was designated as KU-MT.

RESULTS

The cell line was successfully maintained both in athymic nude mice and in culture. Histological examination showed that the xenografted tumours were composed of cells in the reticular, solid and glandular patterns of a yolk sac tumour, and of embryonal carcinoma cells. These cells immunostained positively for AFP. On electron microscopy, the extracellular deposition of a basement lamina-like substance, a typical feature of yolk sac tumour, was detected. The AFP production in mice correlated well with the tumour weight of the xenograft. The cultured KU-MT cells were oval to polygonal in morphology and grew exponentially, with a population doubling time of approximately 2 days. Chromosomal analysis showed a modal number of 57 with consistent structural abnormalities of +add(1)(p13), del(1)(q32), del(2)(q31), add(6) (q21), +add(9)(p22), add(11)(p15), and add(14)(p11). Reverse-transcription polymerase chain reaction analysis showed that the retinoic acid receptors (RAR)-alpha, RAR-gamma, and retinoid X receptor-alpha were present in the cells. The expression of AFP mRNA was up-regulated in response to all-trans-retinoic acid; treatment with this agent caused morphological changes and induced apoptosis in the cells.

CONCLUSIONS

This newly established cell line provides a reproducible model system that should offer a good insight into the differentiation of testicular carcinoma.

Renal fibroblast-like cells in Goodpasture syndrome rats

BACKGROUND

The extent of renal fibrosis is the best predictor for functional outcomes in a variety of progressive renal diseases. Interstitial fibroblast-like cells (FbLCs) are presumably involved in the fibrotic process. However, such FbLCs have never been well characterized in the kidney.

METHODS

We characterized renal FbLCs in the nephritic kidney (in which the number of FbLCs and extracellular matrix accumulation were significantly increased) with regards to their expression of phenotypic and functional markers using day 49 Goodpasture syndrome (GPS) rats.

RESULTS

Within the renal cortical interstitium, there were a number of alpha-smooth muscle actin(+) (alpha-SMA(+)) FbLCs, negative for vimentin (VIM) and transforming growth factor-beta 1, and not equipped with well-developed rough endoplasmic reticulum and actin-stress fibers. All of these findings were incompatible with the typical features of granulation tissue alpha-SMA(+) myofibroblasts. On the other hand, FbLCs negative for alpha-SMA and VIM produced alpha1(I) procollagen in the nephritic kidney.

CONCLUSION

A number of FbLC populations reside within the cortical interstitium of the kidney in GPS rats, each of which is likely to have developed independently in response to the local conditions of the nephritic kidney, contributing to renal fibrogenesis. Further studies are needed to clarify the key type of FbLC that orchestrates other members to produce renal fibrosis.

Optimum treatment strategy for superficial esophageal cancer: endoscopic mucosal resection versus radical esophagectomy

This study was designed to determine the optimum treatment for a superficial esophageal cancer involving the mucosal or submucosal layer of the esophagus. The subjects were 150 patients with a superficial esophageal cancer who underwent endoscopic mucosal resection (EMR) or esophagectomy in Kurume University Hospital from 1981 to 1997. The mortality and morbidity rates, survival rate, and recurrence rate were retrospectively compared for (1) 35 patients who underwent EMR and 37 patients who underwent esophagectomy for a mucosal esophageal cancer and (2) 45 patients who underwent extended radical esophagectomy and 33 patients who underwent less radical esophagectomy for a submucosal esophageal cancer. Among the 72 patients with a mucosal cancer, lymph node metastasis/recurrence was observed in only one (1%); whereas of 78 patients with a submucosal cancer it was observed in 30 (38%). Among patients with a mucosal cancer the mortality and morbidity rates after EMR were lower than for those after esophagectomy. The survival rate after EMR was the same as that after esophagectomy. No recurrence was observed after either treatment modality. Among the patients with a submucosal cancer, the survival rate was higher and the recurrence rate lower after extended radical esophagectomy; than after less radical esophagectomy; the mortality and morbidity rates after extended radical esophagectomy were the same as those after less radical esophagectomy. Multivariate analysis demonstrated that the treatment modality (EMR versus esophagectomy) did not influence the survival of patients with a mucosal esophageal cancer, whereas it strongly influenced the survival of patients with a submucosal esophageal cancer. We concluded that EMR was the mainstay of treatment for a mucosal esophageal cancer, and extended radical esophagectomy was the mainstay of treatment for a submucosal esophageal cancer.

Dose measurements in inhomogeneous bone/tissue and lung/tissue phantoms for angiography using synchrotron radiation

For angiography using synchrotron radiation we measured the absorbed dose distribution in inhomogeneous phantoms with thin LiF:Mg, Cu, P, LiF:Mg, Ti thermoluminescent dosimeters (TLDs) in tissue and lung substitutes, and with Mg2SiO4:Tb TLDs in bone substitute for 33.32 keV monoenergetic photons from synchrotron radiation. The energy responses of the TLDs were measured in air for 10-40 keV monoenergetic photons. The values at 30 keV became smaller by 30% for LiF:Mg, Cu, P and larger by 22% for Mg2SiO4:Tb than the ratio of the mass energy absorption coefficients of the TLDs to that of air. These values were used to modify the calculated response of the TLDs in each phantom material. The absorbed dose distribution obtained was compared with that calculated using the Monte Carlo transport code EGS4 expanded to a low-energy region, and their agreement was confirmed taking linear polarization into account. In the bone substitute the dose increased by a factor of 3.9, while behind the bone the dose decreased drastically because of photon attenuation. In the lung substitute a slight dose difference from that in soft tissue was observed because of its different density. The LiF:Mg, Cu, P TLDs exhibited a better energy response, higher sensitivity and wider linear regions than did the other tissue-equivalent TLDs in the low-energy region.

Chromosomal instability in BRCA1- or BRCA2-defective human cancer cells detected by spontaneous micronucleus assay

The BRCA1 and BRCA2 gene products are believed to play an important part in the onset and/or development of many sporadic mammary cancers. Recently, it has been reported that these two proteins contribute to a centrosome function which is believed to help maintain the integrity of the chromosome segregation process. This may mean a reduced level of the BRCA1 or BRCA2 protein in mammary cells will occasionally lead to nondisjunctional chromosomal loss or gain. We now report that spontaneous micronuclei arising from chromosome(s) which fail to be incorporated into the relevant daughter nuclei during mitosis tend to occur more frequently in BRCA1- or BRCA2-defective human cancer cells than in BRCA-positive cancer cells. Some cases of mammary carcinogenesis may therefore stem from the loss of integrity of chromosome segregation in cells which have a reduced capacity to express either BRCA1 or BRCA2.

X-ray diffraction study on ordered, disordered and reconstituted intercellular lipid lamellar structure in stratum corneum

From small angle X-ray diffraction for the stratum corneum of hairless mouse, it was obtained that in the normal stratum corneum, the 1st, 2nd and 3rd order diffraction peaks for the intercellular lipid lamellar structure appear at 13.8, 6.87 and 4.59 nm, respectively and also a broad hump for the 4th order reflection appears as observed by the previous researchers. In the damaged stratum corneum prepared by the treatment of sodium dodecyl sulfate, these small-angle diffraction peaks disappear and only the broad maxima remain around the 1st, 2nd and 3rd order diffraction peaks. These facts indicate that in the normal stratum the lamellar structure is ordered and in the damaged stratum corneum the lamellar structure is disordered. Furthermore, in the reconstituted lamellar structure obtained by immersing into the dilute suspension of the mixture of ceramide 3, cholesterol and stearic acid, the 1st, 2nd and 3rd order diffraction peaks reappear at 13.3, 6.67 and 4.44 nm, respectively. This fact indicates that the reorganization of the ordered lamellar structure takes place by adding the mixture to the damaged stratum corneum.

Radioactivity induced in a 2.5 GeV electron beam dump

The saturation activity of residual nuclei was estimated based on measurements when 2.5 GeV electron beams were totally absorbed in thick Al, Fe, Cu and Pb. A calculation was also made for a beam dump from 0.1 to 10 GeV using the EGS4 and PICA95 Monte Carlo codes. Above 1 GeV, the activity was constant in units of MBq.W-1. The gamma ray dose rates from the targets were calculated using these data.

Comparison of in-phantom dose distributions for coronary angiography using an x-ray machine and synchrotron radiation

Coronary cineangiography using synchrotron radiation is anticipated, owing to the high intensity and availability of monoenergy. To investigate allowable dose levels in clinical application, absorbed dose distribution in a tissue substitute phantom for a conventional x-ray machine was measured with thermoluminescent dosimeters at the University of Tsukuba under the practical conditions used for digital angiography. The dose rate at a 0.5-cm depth was 0.145 Gy/s, and the dose per frame was 0.725 mGy for the irradiation period of 5 ms per frame. For synchrotron radiation, the dose distribution measurement was made at a 5-GeV AR (Accumulation Ring) of the High Energy Accelerator Research Organization, in which a polymethylmethacrylate (PMMA) phantom was irradiated with the strongest beam available at the facility, which was 33.32 keV, 5.2 x 6.2 cm2 beam. Using this beam, a 1-mm-diameter coronary artery has been visualized at 1% iodine concentration at the AR. Nonhomogeneous strength distribution in the beam was observed in the vertical direction. The maximum dose rate was 0.556 Gy/s, and it attenuated to 1/3000 at a 30-cm depth in the beam center. At the deep positions, the doses were influenced by the high harmonics, which was confirmed with an EGS4 Monte Carlo calculation. Outside the beam, beam contamination on both sides of the main beam affected the doses. For comparison to the x-ray machine, the measured dose was analytically converted to that needed for a 5.2 x 16 cm2 beam that is used for clinical application. The dose rate at 0.5-cm depth was found to be 0.215 Gy/s, which is 1.48 times larger than that for x-rays. Moreover, the attenuation rate in the phantom was significantly greater than that of the x-ray machine, because of the difference of the energy spectra between the x-rays and synchrotron radiation used.

HUman MicroNucleus project: international database comparison for results with the cytokinesis-block micronucleus assay in human lymphocytes: I. Effect of laboratory protocol, scoring criteria, and host factors on the frequency of micronuclei

Micronucleus (MN) expression in peripheral blood lymphocytes is well established as a standard method for monitoring chromosome damage in human populations. The first results of an analysis of pooled data from laboratories using the cytokinesis-block micronucleus (CBMN) assay and participating in the HUMN (HUman MicroNucleus project) international collaborative study are presented. The effects of laboratory protocol, scoring criteria, and host factors on baseline micronucleated binucleate cell (MNC) frequency are evaluated, and a reference range of "normal" values against which future studies may be compared is provided. Primary data from historical records were submitted by 25 laboratories distributed in 16 countries. This resulted in a database of nearly 7000 subjects. Potentially significant differences were present in the methods used by participating laboratories, such as in the type of culture medium, the concentration of cytochalasin-B, the percentage of fetal calf serum, and in the culture method. Differences in criteria for scoring micronuclei were also evident. The overall median MNC frequency in nonexposed (i.e., normal) subjects was 6.5 per thousand and the interquartile range was between 3 and 12 per thousand. An increase in MNC frequency with age was evident in all but two laboratories. The effect of gender, although not so evident in all databases, was also present, with females having a 19% higher level of MNC frequency (95% confidence interval: 14-24%). Statistical analyses were performed using random-effects models for correlated data. Our best model, which included exposure to genotoxic factors, host factors, methods, and scoring criteria, explained 75% of the total variance, with the largest contribution attributable to laboratory methods.

Interfacial oxidations of pure titanium and titanium alloys with investments

External oxides of a commercially pure titanium (cpTi), Ti6Al4V alloy, and an experimental beta-type titanium alloy (Ti 53.4 wt%, Nb 29 wt%, Ta 13 wt%, and Zr 4.6 wt%) were characterized after heating to 600, 900, 1150, and 1400 degrees C in contact with three types of investments (alumina cement, magnesia cement, and phosphate-bonded) in air. XRD studies demonstrated that MgO, Li2TiO3 and/or Li2Ti3O7 were formed through reactions with the metal and the constituents in the magnesia cement-investment after heating to 900, 1150, and 1400 degrees C. Except for these conditions, TiO2 (rutile) was only formed on cpTi. For titanium alloys, the other components apart from Ti also formed simple and complex oxides such as Al2O3 and Al2TiO5 on Ti6Al4V, and Zr0.25Ti0.75Nb2O7 on the beta-type titanium alloy. However, no oxides containing V or Ta were formed. These results suggest that the constituents of titanium alloys reacted with the investment oxides and atmospheric oxygen to form external oxides due to the free energy of oxide formation and the concentration of each element on the metal surface.

Phenotypic change of muscularis mucosae in early invasive colorectal adenocarcinoma

BACKGROUND

Invasive colorectal adenocarcinomas have bundles of eosinophilic spindle cells, which are regarded as myofibroblasts, in their desmoplastic stroma, some of which are continuous with the muscularis mucosa.

AIM

To investigate the relation between the eosinophilic spindle cells and the muscularis mucosa based on their cytoskeletal phenotypes in early invasive colorectal adenocarcinoma.

METHODS

Formalin fixed, paraffin wax embedded tissues of 17 early invasive colorectal adenocarcinomas were immunostained for alpha-smooth muscle actin (alpha-SMA), desmin, and vimentin.

RESULTS

The phenotype of the muscularis mucosa was alpha-SMA positive, desmin positive, and vimentin weakly positive, whereas the eosinophilic spindle cells showed a decreased degree of immunoreactivity for alpha-SMA and desmin in particular, and an increased degree of immunoreactivity for vimentin. The degree of phenotypic difference between the muscularis mucosa and the eosinophilic spindle cells was greater in the eosinophilic spindle cells in the centre of the invasive area that were not continuous with the muscularis mucosa than in the eosinophilic spindle cells continuous with the muscularis mucosa.

CONCLUSIONS

These findings suggest that the smooth muscle cells of the muscularis mucosa change their phenotype to become eosinophilic spindle cells, namely myofibroblasts, in the early invasive area of colorectal adenocarcinoma.

Chorioangioma: antenatal diagnosis with fast MR imaging

We report a case of chorioangioma of the placenta, in which fast magnetic resonance imaging (MRI) was useful adjunct to ultrasonography for the antenatal diagnosis. MRI allowed clear demonstration of 6.8 x 6.0 cm solid placental mass along with hydramnios and anatomically normal fetus. On T(1)-weighted breath-hold spoiled gradient-echo (fast low-angle shot [FLASH]) images, chorioangioma was mostly isointense to the placenta, but had an area of high signal intensity near the base and at the periphery, suggestive of hemorrhage. On T(2)-weighted half-Fourier single-shot fast spin echo (HASTE) images, the mass showed heterogeneous high signal intensity, but had an area of low signal intensity near the surface.

Progressive renal fibrosis in murine polycystic kidney disease: an immunohistochemical observation

BACKGROUND

The appearance of interstitial fibrosis in polycystic kidneys is emblematic of progressive disease. Matrix forming this scar tissue is derived from local renal cells in response to cystogenesis. We investigated the phenotype of collagen-producing cells in the cystic kidneys of DBA/2-pcy mice to better characterize the spectrum of interstitial cells associated with renal fibrogenesis.

METHODS

The extent of interstitial fibrosis and the number of fibroblasts in cystic kidneys were first quantitated over time using computer-assisted image analysis. Subsequently, antisera to four cell protein markers were studied by coexpression immunohistochemistry during progression of fibrosis using confocal microscopy. The antisera included fibroblast-specific protein 1 (FSP1) for fibroblast phenotype, alpha-smooth muscle actin (alpha-SMA) for contractile phenotype, vimentin (VIM) for mesenchymal phenotype, and heat shock protein 47 (HSP47) for interstitial collagen-producing phenotype.

RESULTS

Interstitial fibrosis in cystic kidneys gradually increased throughout the 30-week observation period of our study. With progression of cystogenesis, most of the tubules in pcy mice either dilated or disappeared with time. FSP1+ fibroblasts were distributed sparsely throughout the renal interstitium of young pcy and wild-type mice. Their number increased in the widening fibrotic septa by 18 weeks of age and persisted through 30 weeks of the study interval. Some epithelia among remnant tubules trapped within fibrotic septa around adjacent cysts also acquired the phenotype of FSP1+, HSP47+ collagen-producing fibroblasts, suggesting a possible role for epithelial-mesenchymal transformation (EMT) in this process. Most FSP1+ fibroblasts were alpha-SMA-, but HSP47+, suggesting they were producing collagen proteins for the extracellular matrix. alpha-SMA+, FSP1-, HSP47+ or HSP47- cells were also observed, and the latter tended to distribute independently in a linear pattern, reminiscent of vasculature adjacent to forming cysts. VIM+ expression was not observed in alpha-SMA+ cells.

CONCLUSIONS

Many nonoverlapping as well as fewer overlapping populations of FSP1+ and alpha-SMA+ cells shared in the collagen expression associated with progressive fibrogenesis in pcy mice undergoing cystogenesis. Some FSP1+ fibroblasts are likely derived from tubular epithelium undergoing EMT, while alphaSMA+, VIM- cells probably represent vascular smooth muscle cells or pericytes surviving vessel attenuation during the chaos of fibrogenesis. Importantly, not all interstitial cells producing collagens are alpha-SMA+.

Hypercalcemia in a patient with renal cell carcinoma producing parathyroid hormone-related protein and interleukin-6

A patient with renal cell carcinoma who developed humoral hypercalcemia of malignancy is reported. A 52-year-old male patient was diagnosed with renal cell carcinoma and multiple lung metastases. A cell line isolated from the surgical specimen exhibited continuous production of parathyroid hormone-related protein (PTHrP) in vitro. The production of PTHrP from the cancer cells was confirmed by RT-PCR and immunoradiometric assay. The serum calcium level was not enhanced, whereas the lung lesion was developing and producing interleukin-6, a possible modulator of osteoclastic resorption. Hypercalcemia was induced when the PTHrP concentration increased up to 3.3 pmol/L.

Inhibition of monocyte chemoattractant protein-1 expression in tubular epithelium attenuates tubulointerstitial alteration in rat Goodpasture syndrome

BACKGROUND

To examine the role of monocyte chemoattractant protein-1 (MCP-1) expressed by tubular epithelium in tubulointerstitial alterations in situ, the level of MCP-1 mRNA in tubular epithelium was lowered selectively in the rat model of Goodpasture syndrome (GPS).

METHODS

Intravenously administered antisense oligodeoxynucleotide (ODN) is taken up by renal tubular epithelium and has been found to block expression of target genes in rats. MCP-1 antisense ODN was injected into GPS rats every second day from days 27 to 35 after immunization (this represents the time when renal MCP-1 mRNA level was increased and interstitial mononuclear cell infiltration was aggravated).

RESULTS

In addition to a reduction in the level of tubular MCP-1 mRNA, antisense ODN treatment attenuated monocyte infiltration significantly and preserved renal function in GPS rats. However, ODN injection did not affect glomerular MCP-1 expression and glomerular histopathology, and there were no significant changes in the urinary protein excretion rate.

CONCLUSION

Our findings provide direct evidence that MCP-1, expressed by tubular epithelium, plays a pivotal role in mediating secondary tubulointerstitial alterations in the GPS model.

Simultaneous production of granulocyte colony-stimulating factor and parathyroid hormone-related protein in bladder cancer

A case of bladder cancer with simultaneous production of granulocyte colony-stimulating factor (G-CSF) and parathyroid hormone-related protein (PTHrP) is reported. An 81-year-old male patient was admitted to the Saitama Medical School for treatment of gross hematuria, leukocytosis and hypercalcemia and diagnosed as having advanced bladder cancer. Immediately after a cystectomy was carried out, his white cell count and serum calcium levels returned to normal. However, the tumors recurred locally and the recurrence was accompanied by an increase in the serum G-CSF and PTHrP levels with a recurrent elevation of white cell count and the serum calcium level. The production of G-CSF and PTHrP in the tumor cells was confirmed by immunohistochemistry.

Osteopontin expressed by renal tubular epithelium mediates interstitial monocyte infiltration in rats

In this study, we have shown that intravenously administered antisense oligodeoxynucleotide (ODN) was demonstrated to be taken up by tubular epithelium, after which it blocked mRNA expression of target genes in normal and nephritic rats. Therefore, we injected osteopontin (OPN) antisense ODN to Goodpasture syndrome (GPS) rats every second day between days 27 and 35, the time when renal OPN expression increased and interstitial monocyte infiltration was aggravated. In parallel to blockade of tubular OPN expression, this treatment significantly attenuated monocyte infiltration and preserved renal plasma flow in GPS rats at day 37, compared with sense ODN-treated and untreated GPS rats. No significant changes were observed in OPN mRNA level by RT-PCR and histopathology of the glomeruli after ODN treatment, which was compatible with an absence of differences in the urinary protein excretion rate. In conclusion, OPN expressed by tubular epithelium played a pivotal role in mediating peritubular monocyte infiltration consequent to glomerular disease.