Parameter variation effects on millimeter wave dosimetry based on precise skin thickness in real rats.

This study presents a parametric analysis of the steady-state temperature elevation in rat skin models due to millimeter wave exposure at frequencies from 6-100 GHz. The statistical data of the thickness of skin layers, namely epidermis, dermis, dermal white adipose tissue, and panniculus carnosus, were measured for the first time using the excised tissues of real male Sprague-Dawley rats. Based on the precise structure obtained from the histological analysis of rat skin, we solve the bioheat transfer equation to investigate the effects of changes in parameters, such as body parts and thermal constants, on the absorbed power density and temperature elevation of biological tissues. Owing to the notably thin dermal white adipose tissue layer, the surface temperature elevation in the rat head and dorsal skin at 6-100 GHz is 52.6-32.3% and 83.3-58.8% of the average values of different human skin models, respectively. Our results also reveal that the surface temperature elevation of rat skin may correlate with the tissue thickness and deep blood perfusion rates.

Excessive whole-body exposure to 28 GHz quasi-millimeter wave induces thermoregulation accompanied by a change in skin blood flow proportion in rats.

Introduction: Limited information is available on the biological effects of whole-body exposure to quasi-millimeter waves (qMMW). The aim of the present study was to determine the intensity of exposure to increase body temperature and investigate whether thermoregulation, including changes in skin blood flow, is induced in rats under whole-body exposure to qMMW. Methods: The backs of conscious rats were extensively exposed to 28 GHz qMMW at absorbed power densities of 0, 122, and 237 W/m2 for 40 minutes. Temperature changes in three regions (dorsal and tail skin, and rectum) and blood flow in the dorsal and tail skin were measured simultaneously using fiber-optic probes. Results: Intensity-dependent temperature increases were observed in the dorsal skin and the rectum. In addition, skin blood flow was altered in the tail but not in the dorsum, accompanied by an increase in rectal temperature and resulting in an increase in tail skin temperature. Discussion: These findings suggest that whole-body exposure to qMMW drives thermoregulation to transport and dissipate heat generated on the exposed body surface. Despite the large differences in size and physiology between humans and rats, our findings may be helpful for discussing the operational health-effect thresholds in the standardization of international exposure guidelines.

Intensity-dependent Temperature Rise Induced by Local Exposure to 26.5 GHz Quasi-Millimeter-Wave in Rat.

BACKGROUND/AIM: The widespread use of fifth-generation 5G millimeter-waves (MMW) generates concern about potential adverse health effects. The latest international guidelines for MMW exposure adopt an absorbed power density (APD) of 200 W/m2 to avoid a local temperature rise of 5°C in human tissues as an operational adverse health effect threshold. However, because APD is estimated by simulations using human tissue models, it is unknown whether a similar value can be confirmed for living tissues. The aim of this study was to investigate the relationship between APD and skin temperature rise in vivo, and to validate the estimated values. MATERIALS AND METHODS: The rat dorsal skin was locally exposed to a 26.5 GHz quasi-MMW (qMMW) for 18 min using a patch antenna. The qMMW exposure intensities estimated by dosimetry were set to 0-500 W/m2 of APD. The temperatures in the dorsal skin and rectum were simultaneously measured during exposure. RESULTS: The qMMW-induced local temperature increase at different sites. The dorsal skin temperature increased by approximately 11.3°C at a maximum intensity of 500 W/m2, but the rectal temperature increased by only 0.6°C, indicating highly localized effects of exposure to rats. A significant correlation was observed between APD and skin temperature rise. The relationship provided a linear regression model, and a temperature rise of less than 5°C was estimated in the skin exposed to 200 W/m2 of APD. CONCLUSION: These results suggest that the operational threshold for the MMW exposure guidelines is valid under the present experimental conditions using rats.

Cross-sectional associations between early mobile device usage and problematic behaviors among school-aged children in the Hokkaido Study on Environment and Children's Health.

BACKGROUND: Concerns have been raised about the adverse health impacts of mobile device usage. The objective of this cross-sectional study was to examine the association between a child's age at the first use of a mobile device and the duration of use as well as associated behavioral problems among school-aged children. METHODS: This study focused on children aged 7-17 years participating in the Hokkaido Study on Environment and Children's Health. Between October 2020 and October 2021, the participants (n = 3,021) completed a mobile device use-related questionnaire and the strengths and difficulties questionnaire (SDQ). According to the SDQ score (normal or borderline/high), the outcome variable was behavioral problems. The independent variable was child's age at first use of a mobile device and the duration of use. Covariates included the child's age at the time of survey, sex, sleep problems, internet addiction, health-related quality of life, and history of developmental concerns assessed at health checkups. Logistic regression analysis was performed for all children; the analysis was stratified based on the elementary, junior high, and senior high school levels. RESULTS: According to the SDQ, children who were younger at their first use of a mobile device and used a mobile device for a longer duration represented more problematic behaviors. This association was more pronounced among elementary school children. Moreover, subscale SDQ analysis showed that hyperactivity, and peer and emotional problems among elementary school children, emotional problems among junior high school children, and conduct problems among senior high school children were related to early and long usage of mobile devices. CONCLUSIONS: Elementary school children are more sensitive to mobile device usage than older children, and early use of mobile devices may exacerbate emotional instability and oppositional behaviors in teenagers. Longitudinal follow-up studies are needed to clarify whether these problems disappear with age.

Measurement of personal radio frequency exposure in Japan: The Hokkaido Study on the Environment and Children's health.

The opportunities for exposure to radiofrequency electromagnetic fields (RF-EMF) among children are increasing. Children's exposure to RF-EMF in Japan was recorded using a personal exposure meter (ExpoM-RF), and factors associated with the exposure examined. A total of 101 children, aged 10-15 years old, participated in the prospective birth cohort "Hokkaido study". RF-EMF data were recorded in the 700 MHz-5.8 GHz frequency range for 3 days. The recorded data were summarized into six groups of frequency bands: downlink from mobile phone base stations (DL), uplink from mobile phones to a base station (UL), Wireless Local Area Network (LAN), terrestrial digital TV broadcasting (digital TV), 2.5 GHz and 3.5 GHz Time Division Duplex (TDD), 1.9 GHz TDD, and total (the summation of power density in all measured frequency bands). A questionnaire was used to document the internet environment (at home) and mobile phone usage. Personal RF-EMF exposure in Japanese children was lower than that reported in studies in Europe. The DL signals from mobile phone base stations were the most significant contributors to total exposure, while Wireless LAN and digital TV were only higher at home. The urban residence was consistently associated with increases in the four groups of frequency bands (DL, UL, digital TV, and TDD). TDD level has several associations with mobile phone usage (calls using mobile phones, video viewing, text message service, and online game). The association between inattention/hyperactivity subscale of the Strengths and Difficulties Questionnaire (SDQ) and higher Wireless LAN exposure at nighttime was also noted. Further studies with additional data will shed light on factors involved in RF-EMF exposure among Japanese children.

Identification of Candidate Genes Responsible for Flower Colour Intensity in Gentiana triflora.

Gentians cultivated in Japan (Gentiana triflora and Gentiana scabra and hybrids) have blue flowers, but flower colour intensity differs among cultivars. The molecular mechanism underlying the variation in flower colour intensity is unclear. Here, we produced F2 progeny derived from an F1 cross of intense- and faint-blue lines and attempted to identify the genes responsible for flower colour intensity using RNA-sequencing analyses. Comparative analysis of flower colour intensity and transcriptome data revealed differentially expressed genes (DEGs), although known flavonoid biosynthesis-related genes showed similar expression patterns. From quantitative RT-PCR (qRT-PCR) analysis, we identified two and four genes with significantly different expression levels in the intense- and faint-blue flower lines, respectively. We conducted further analyses on one of the DEGs, termed GtMIF1, which encodes a putative mini zinc-finger protein homolog, which was most differently expressed in faint-blue individuals. Functional analysis of GtMIF1 was performed by producing stable tobacco transformants. GtMIF1-overexpressing tobacco plants showed reduced flower colour intensity compared with untransformed control plants. DNA-marker analysis also confirmed that the GtMIF1 allele of the faint-blue flower line correlated well with faint flower colour in F2 progeny. These results suggest that GtMIF1 is one of the key genes involved in determining the flower colour intensity of gentian.

Novel 60 GHz Band Spatial Synthetic Exposure Setup to Investigate Biological Effects of 5G and Beyond Wireless Systems on Human Body.

The global spread of 5th generation (5G) wireless systems causes some concern about health effects of millimeter waves (MMW). To investigate biological effects of local exposure to 5G-MMW on human body, a novel 60 GHz band exposure setup was developed, and its performance was validated. A spatial synthetic beam-type exposure setup using two dielectric lens antennas was proposed to achieve high intensity 60 GHz irradiation to the target area of human skin. Variety distributions and intensities of electromagnetic fields at the exposed area, which is modified by incident angles of the combined beams, were simulated using finite-difference time-domain methods. The exposure performance we estimated was verified by temperature elevations of surface in a physical arm-shaped silicone phantom during the MMW exposure. The interference fringes generated in the exposed area due to the combined two-directional beam radiations were observed both in the simulation and in the phantom experiment but eliminated by applying an orthogonalizing polarized feeding structure. Under these exposure conditions, the local temperature changes, which could evoke warmth sensations, were obtained at the target area of the human forearm skin, which means the achievement of exposure performance we intended.

Identification and characterization of xanthone biosynthetic genes contributing to the vivid red coloration of red-flowered gentian.

Cultivated Japanese gentians traditionally produce vivid blue flowers because of the accumulation of delphinidin-based polyacylated anthocyanins. However, recent breeding programs developed several red-flowered cultivars, but the underlying mechanism for this red coloration was unknown. Thus, we characterized the pigments responsible for the red coloration in these cultivars. A high-performance liquid chromatography with photodiode array analysis revealed the presence of phenolic compounds, including flavones and xanthones, as well as the accumulation of colored cyanidin-based anthocyanins. The chemical structures of two xanthone compounds contributing to the coloration of red-flowered gentian petals were determined by mass spectrometry and nuclear magnetic resonance spectroscopy. The compounds were identified as norathyriol 6-O-glucoside (i.e., tripteroside designated as Xt1) and a previously unreported norathyriol-6-O-(6'-O-malonyl)-glucoside (designated Xt2). The copigmentation effects of these compounds on cyanidin 3-O-glucoside were detected in vitro. Additionally, an RNA sequencing analysis was performed to identify the cDNAs encoding the enzymes involved in the biosynthesis of these xanthones. Recombinant proteins encoded by the candidate genes were produced in a wheat germ cell-free protein expression system and assayed. We determined that a UDP-glucose-dependent glucosyltransferase (StrGT9) catalyzes the transfer of a glucose moiety to norathyriol, a xanthone aglycone, to produce Xt1, which is converted to Xt2 by a malonyltransferase (StrAT2). An analysis of the progeny lines suggested that the accumulation of Xt2 contributes to the vivid red coloration of gentian flowers. Our data indicate that StrGT9 and StrAT2 help mediate xanthone biosynthesis and contribute to the coloration of red-flowered gentians via copigmentation effects.

Exposure to Radiofrequency Electromagnetic Field in the High-Frequency Band and Cognitive Function in Children and Adolescents: A Literature Review.

With increasing use of mobile phones, exposure to radiofrequency electromagnetic field (RF-EMF) in the high-frequency band associated with mobile phones has become a public concern, with potentially adverse effects on cognitive function in children and adolescents. However, findings regarding the relation of RF-EMF and cognitive function in children and adolescents have been inconsistent due to a number of study design-related factors, such as types of exposure and outcome measures, age of participants, and the era of study conduction. The present literature review focused on these possible factors that could explain this inconsistency. This review identified 12 eligible studies (participants ages 4 to 17 years) and extracted a total 477 relations. In total, 86% of the extracted relations were not statistically significant; in the remaining 14%, a negative relation between RF-EMF and cognitive performance was detected under limited conditions: when (1) RF-EMF was assessed using objective measurement not subjective measurement (i.e., questionnaire), (2) participants were relatively older (12 years and above) and had greater opportunity of exposure to RF-EMF, and (3) the collection of cognitive function data was conducted after 2012. Given that 86% of the extracted relations in this analysis were not statistically significant, the interpretation should be approached with caution due to the possibility of the 14% of significant relationships, extracted in this review, representing chance findings.

The Host Stomatal Density Determines Resistance to Septoria gentianae in Japanese Gentian.

Plant stomata represent the main battlefield for host plants and the pathogens that enter plant tissues via stomata. Septoria spp., a group of ascomycete fungi, use host plant stomata for invasion and cause serious damage to agricultural plants. There is no evidence, however, showing the involvement of stomata in defense systems against Septoria infection. In this study, we isolated Septoria gentianae 20-35 (Sg20-35) from Gentiana triflora showing gentian leaf blight disease symptoms in the field. Establishment of an infection system using gentian plants cultured in vitro enabled us to observe the Sg20-35 infection process and estimate its virulence in several gentian cultivars or lines. Sg20-35 also entered gentian tissues via stomata and showed increased virulence in G. triflora compared with G. scabra and their interspecific hybrid. Notably, the susceptibility of gentian cultivars to Sg20-35 was associated with their stomatal density on the adaxial but not abaxial leaf surface. Treatment of EPIDERMAL PATTERNING FACTOR-LIKE 9 (EPFL9/STOMAGEN) peptides, a small secreted peptide controlling stomatal density in Arabidopsis thaliana, increased stomatal density on the adaxial side of gentian leaves as well. Consequently, treated plants showed enhanced susceptibility to Sg20-35. These results indicate that stomatal density on the adaxial leaf surface is one of the major factors determining the susceptibility of gentian cultivars to S. gentianae and suggest that stomatal density control may represent an effective strategy to confer Septoria resistance.

Production of interspecific hybrids between Japanese gentians and wild species of Gentiana.

Wide hybridization, which is a powerful tool to broaden genetic variation, has been used in breeding of many crops. However, in ornamental gentian few wide hybridizations have been reported. Interspecific hybridizations between two gentian cultivated species (Gentiana scabra and G. triflora) and 11 wild species, which were classified in five sections, were carried out using ovule culture. When G. scabra was used as a female parent, normal seedlings and hybrid plants were obtained from eight and five interspecific combinations, respectively. The yield of seedling produced from ovule culture depended on interspecific combinations, ranging from 0.3 to 427.7 normal seedling per flower. In the hybridization of G. triflora with five wild species, normal seedlings and plants were produced in five and four interspecific combinations, respectively. The yield of normal seedling ranging from 0.4 to 228.3 was different between not only interspecific combinations but also reciprocal crosses. Two cultivated species are classified in sect. Pneumonanthe, and successful production of hybrids was obtained from the hybridization with species classified in sections Pneumonanthe or Cruciata. The hybrid nature of the produced plants was confirmed by molecular marker and morphology. The production of interspecific hybrids opens a novel prospect in ornamental gentian breeding.

Active implantable medical device EMI assessment for wireless power transfer operating in LF and HF bands.

The electromagnetic interference (EMI) imposed on active implantable medical devices by wireless power transfer systems (WPTSs) is discussed based upon results of in vitro experiments. The purpose of this study is to present comprehensive EMI test results gathered from implantable-cardiac pacemakers and implantable cardioverter defibrillators exposed to the electromagnetic field generated by several WPTSs operating in low-frequency (70 kHz-460 kHz) and high-frequency (6.78 MHz) bands. The constructed in vitro experimental test system based upon an Irnich's flat torso phantom was applied. EMI test experiments are conducted on 14 types of WPTSs including Qi-compliant system and EV-charging WPT system mounted on current production EVs. In addition, a numerical simulation model for active implantable medical device (AIMD) EMI estimation based on the experimental test system is newly proposed. The experimental results demonstrate the risk of WPTSs emitting intermittent signal to affect the correct behavior of AIMDs when operating at very short distances. The proposed numerical simulation model is applicable to obtain basically the EMI characteristics of various types of WPTSs.

Identification and functional analysis of SVP ortholog in herbaceous perennial plant Gentiana triflora: Implication for its multifunctional roles.

Information concerning to regulation of vegetative phase and floral initiation in herbaceous perennial plants has been limited to a few plant species. To know and compare flowering regulation in a wider range of plant species, we identified and characterized SHORT VEGETATIVE PHASE (SVP)-like genes (GtSVP-L1 and GtSVP-L2) from herbaceous perennial gentian (Gentiana triflora). Apple latent spherical virus (ALSV)-mediated silencing of the GtSVP-L1 in G. triflora seedlings resulted in early flowering and shortened vegetative phase by about one-third period of time, without vernalization. This indicated that GtSVP-L1 acts as a negative regulator of flowering and vegetative phase. Seasonal change in the expression of GtSVP was monitored in the overwinter buds (OWBs) of G. triflora. It was found that the levels of GtSVP-L1 mRNA in OWBs increased concomitantly with induction and/or maintenance of dormancy, then decreased toward release from dormancy, while that of GtSVP-L2 mRNA remained low and unchanged. These results implied that, in herbaceous perennial plants, SVP ortholog might concern to activity-dormancy control, as well as negative regulation in flowering. Practically, these results can be applicable to non-time-consuming technologies for breeding.

Allelic variants of the esterase gene W14/15 differentially regulate overwinter survival in perennial gentian (Gentiana L.).

Overwinter survival has to be under critical regulation in the lifecycle of herbaceous perennial plants. Gentians (Gentiana L.) maintain their perennial life style through producing dormant and freezing-tolerant overwinter buds (OWBs) to overcome cold winter. However, the mechanism acting on such an overwinter survival and the genes/proteins contributing to it have been poorly understood. Previously, we identified an OWB-enriched protein W14/15, a member of a group of α/ß hydrolase fold superfamily that is implicated in regulation of hormonal action in plants. The W14/15 gene has more than ten variant types in Gentiana species. However, roles of the W14/15 gene in OWB survival and functional difference among those variants have been unclear. In the present study, we examined whether the W14/15 gene variants are involved in the mechanism acting on overwinter survival, by crossing experiments using cultivars carrying different W14/15 variant alleles and virus-induced gene silencing experiments. We found that particular types of the W14/15 variants (W15a types) contributed toward obtaining high ability of overwinter survival, while other types (W14b types) did not, or even interfered with the former type gene. This study demonstrates two findings; first, contribution of esterase genes to winter hardiness, and second, paired set or paired partner among the allelic variants determines the ability of overwinter survival.

Efficient haploid and doubled haploid production from unfertilized ovule culture of gentians (Gentiana spp.).

Factors affecting reliable plant regeneration from unfertilized ovule culture of gentians (Gentiana spp.) were examined. Cold pretreatment (4°C) of flower buds enhanced or maintained production of embryo-like structure (ELS). When 43 genotypes were surveyed in two different labs, 40 of them produced ELSs ranging from 0.01 to 26.5 ELSs per flower bud. No ELSs could be obtained in three genotypes. A significant correlation (r = 0.64) was observed between the number of ELS per flower and the frequency of responding flower buds. Eight genotypes of G. triflora, which were used as common materials in two different labs, produced ELSs in both labs. The ploidy levels of a total of 1,515 regenerated plantlets were determined, revealing that the majority of these plants consisted of haploids (57.9%) and diploids (34.3%). However, the frequency of haploids and diploids was different between G. triflora and G. scabra, and G. triflora showed higher frequencies of haploids than G. scabra. When haploids were treated with oryzalin for chromosome doubling, diploids and tetraploids were obtained. These results demonstrate that the unfertilized ovule culture technique of gentians is a powerful tool for obtaining haploids and DHs because of its reproducible and reliable nature and application to a wide range of genotypes.

Construction of the first genetic linkage map of Japanese gentian (Gentianaceae).

BACKGROUND: Japanese gentians (Gentiana triflora and Gentiana scabra) are amongst the most popular floricultural plants in Japan. However, genomic resources for Japanese gentians have not yet been developed, mainly because of the heterozygous genome structure conserved by outcrossing, the long juvenile period, and limited knowledge about the inheritance of important traits. In this study, we developed a genetic linkage map to improve breeding programs of Japanese gentians. RESULTS: Enriched simple sequence repeat (SSR) libraries from a G. triflora double haploid line yielded almost 20,000 clones using 454 pyrosequencing technology, 6.7% of which could be used to design SSR markers. To increase the number of molecular markers, we identified three putative long terminal repeat (LTR) sequences using the recently developed inter-primer binding site (iPBS) method. We also developed retrotransposon microsatellite amplified polymorphism (REMAP) markers combining retrotransposon and inter-simple sequence repeat (ISSR) markers. In addition to SSR and REMAP markers, modified amplified fragment length polymorphism (AFLP) and random amplification polymorphic DNA (RAPD) markers were developed. Using 93 BC1 progeny from G. scabra backcrossed with a G. triflora double haploid line, 19 linkage groups were constructed with a total of 263 markers (97 SSR, 97 AFLP, 39 RAPD, and 30 REMAP markers). One phenotypic trait (stem color) and 10 functional markers related to genes controlling flower color, flowering time and cold tolerance were assigned to the linkage map, confirming its utility. CONCLUSIONS: This is the first reported genetic linkage map for Japanese gentians and for any species belonging to the family Gentianaceae. As demonstrated by mapping of functional markers and the stem color trait, our results will help to explain the genetic basis of agronomic important traits, and will be useful for marker-assisted selection in gentian breeding programs. Our map will also be an important resource for further genetic analyses such as mapping of quantitative trait loci and map-based cloning of genes in this species.

A single-base substitution suppresses flower color mutation caused by a novel miniature inverted-repeat transposable element in gentian.

We investigated the genetic basis for the derivation of pink coloration in petals from blue flowers in cultivated gentians. Using a revertant blue-flower phenotype that arose spontaneously from a pink-flowered cultivar, we sought to elucidate the molecular mechanism of flower color restoration caused by a suppressor mutation. Detailed sequencing analysis identified three novel deficient flavonoid 3',5'-hydroxylase (F3'5'H) alleles in pink-flowered gentians in addition to two mutations identified previously (Nakatsuka et al. in Mol Genet Genomics 275:231-241, 2006). Among the deficient alleles, one allele that contained a novel miniature inverted-repeat transposable element (GtMITE1) insertion in an intron of F3'5'H was shown to cause missplicing, resulting in abnormal F3'5'H transcripts and the pink-flower phenotype. The other two mutations were identified as a single-nucleotide insertion and gypsy-Ty3 retrotransposon (Tgt1) insertion within exon 1 and exon 2 of the F3'5'H gene, respectively. The blue-flowered revertant mutant contained a single-nucleotide spontaneous mutation immediately 3' of the TAA target site duplication and the GtMITE1 insertion, which caused restoration of normal splicing of F3'5'H and the normal blue-flower phenotype. Transient expression assays in gentian flowers in vivo demonstrated that normal F3'5'H splicing pattern was recovered from missplicing induced by the GtMITE1 insertion by the single-nucleotide substitution. These findings extend our knowledge of genomic evolution by transposable elements and spontaneous mutations in Gentiana species of economic and medical importance.

Gynogenesis in gentians (Gentiana triflora, G. scabra): production of haploids and doubled haploids.

Gynogenesis was investigated on gentian (Gentiana triflora, G. scabra and their hybrids), which is an important ornamental flower. When unfertilized ovules were cultured in 1/2 NLN medium containing a high concentration of sucrose (100 g/l), embryo-like structures (ELS) were induced. Although genotypic variation was observed in ELS induction, all four genotypes produced ELSs ranging from 0.93 to 0.04 ELSs per flower bud. The ovules collected from flower buds of later stages (just before anthesis or flower anthesis) tended to exhibit higher response. The dark culture condition produced more than four times as many ELSs than in 16-h light condition. A significant number of plantlets were directly regenerated from ELSs on MS regeneration medium. The ploidy levels of 179 regenerated plants were determined by flow cytometry, revealing that the majority of them were diploid (55.9%) and haploid (31.3%). When a total of 54 diploid plants were examined by molecular genetic markers, 52 (96.3%) were considered as doubled haploids (DHs). This is the first report showing successful gynogenesis in gentian. The production of haploids and DHs by unfertilized ovule culture opens a novel prospect in gentian F1 hybrid breeding.

Effects on rat testis of 1.95-GHz W-CDMA for IMT-2000 cellular phones.

In recent years concern has arisen whether carrying a cellular phone near the reproductive organs such as the testes may cause dysfunction and particularly decrease in sperm development and production, and thus fertility in men. The present study was performed to investigate the effects of a 1.95 GHz electromagnetic field on testicular function in male Sprague-Dawley rats. Five week old animals were divided into 3 groups of 24 each and a 1.95-GHz wide-band code division multiple access (W-CDMA) signal, which is used for the freedom of mobile multimedia access (FOMA), was employed for whole body exposure for 5 hours per day, 7 days a week for 5 weeks (the period from the age of 5 to 10 weeks, corresponding to reproductive maturation in the rat). Whole-body average specific absorption rates (SAR) for individuals were designed to be 0.4 and 0.08 W/kg respectively. The control group received sham exposure. There were no differences in body weight gain or weights of the testis, epididymis, seminal vesicles, and prostate among the groups. The number of sperm in the testis and epididymis were not decreased in the electromagnetic field (EMF) exposed groups, and, in fact, the testicular sperm count was significantly increased with the 0.4 SAR. Abnormalities of sperm motility or morphology and the histological appearance of seminiferous tubules, including the stage of the spermatogenic cycle, were not observed. Thus, under the present exposure conditions, no testicular toxicity was evident.

W14/15 esterase gene haplotype can be a genetic landmark of cultivars and species of the genus Gentiana L.

We have identified multiple alleles for a single gene termed W14/15. This gene encodes closely related but not identical proteins W14 and W15 that accumulate in overwinter buds of Gentiana triflora (Takahashi et al. in Breed Sci 56:39-46, 2006; Hikage et al. in Mol Genet Genomics 278:95-104, 2007). In this study, structural analysis of the W14/15 gene was carried out for 21 different gentian lines/cultivars consisting of 5 different species, to survey species- or line/cultivar-specific haplotypes. Within the samples examined, multiple variant forms were found. Those were categorized into seven major types (type I-VII) and ten subtypes based on the presence of three short insertion/deletion sites, three RFLP sites, and several SNP sites. Each line/cultivar had a distinct set of W14/15 gene variants for an allelic pair. Phylogenetic analysis showed that the W14/15 alleles cluster into groups that are characteristic of gentian species, i.e., G. triflora, G. scabra, G. pneumonanthe, G. septemfida and an unknown species other than the former four. In addition, within the same gentian species, different sets of haplotypes were found. Thus, the W14/15 alleles provide useful landmarks to resolve phylogenies of the genus or section Gentiana, as well as to analyze pedigree and breeding history of the cultivars derived from those Gentiana sp.