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1.
Zookeys ; 1146: 115-134, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37214591

RESUMEN

Euborellia (Anisolabididae: Anisolabidinae) is one of the most speciose genera of earwigs (Dermaptera), and its species-level classification is difficult. To settle the classification of brachypterous species with abbreviated tegmina recorded from East and Southeast Asia, we examined the morphology and reproductive isolation of three tentative Euborellia species, and analyzed the DNA barcoding region of the mitochondrial cytochrome oxidase subunit I (COI) gene. The observed complete reproductive isolation among the three Euborellia taxa and considerable differentiation in the COI sequences clearly show that each should be treated as a separate species. Based on morphology, distribution and the DNA sequence, we identify Euborellia sp. 1 of Malaysia as E.annulata (Fabricius), a circumtropical cosmopolitan with no records of a fully winged form. Samples from Ioto Island (= Iwo-jima Island: Ogasawara Islands, southern Japan) were also identified as this species. Euborellia sp. 3, from the main islands of Japan, was generally larger and lacked a Y-shaped pigmented area on the penis lobe, which is characteristic of Euborellia sp. 1. We propose reinstating E.pallipes (Shiraki) as the oldest name for this taxon. Euborellia sp. 2, even the brachypterous form, can be distinguished from these two species by its paler coloration (particularly the femora), ecarinate post-abdomen, and the shape of the male genitalia (parameres). We tentatively identify this species as E.philippinensis Srivastava based on the morphology of the brachypterous form, although the macropterous form cannot be distinguished from E.femoralis (Dohrn).

2.
Biodivers Data J ; 11: e107001, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38318508

RESUMEN

Dermaptera is a polyneopteran insect order that includes more than 2,000 described species, commonly known as earwigs, that mainly inhabit tropical, subtropical and warm temperate regions. Although 40 species have been found in Japan, their distribution and habitat preferences have remained ambiguous due to sample misidentification, particularly amongst immature specimens. To overcome this problem, we sequenced and analysed the DNA barcoding region of the mitochondrial cytochrome oxidase I gene (cox1) of dermapteran species recorded from Japan. Including publicly available data, 72.5% of known Japanese dermapteran species were subjected to molecular identification. We extensively sampled three wingless species of subfamily Anisolabidinae (Anisolabididae): Anisolabismaritima, Anisolabellamarginalis and Euborelliapallipes. Although these species exhibit similar habitat preferences as semi-synanthropes, A.maritima, a cosmopolitan species with the highest affinity to seashore, had significantly higher sequence diversity than the latter two species, which are considered endemic to East Asia. A similar trend was observed for (at least partly) winged cosmopolitan species of other families. Introgression with the congener Anisolabisseirokui is also suggested for A.maritima. Possible causes of the varying levels of sequence diversity are discussed.

3.
Endocr J ; 69(12): 1407-1414, 2022 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-35934795

RESUMEN

The development of pancreatic cancer (PC) is associated with worsening of glucose tolerance. However, there is limited information about the effects of PC on islet morphology. The aim of this study was to elucidate changes in alpha and beta cell mass in patients with PC. We enrolled 30 autopsy cases with death due to PC (9 with diabetes; DM) and 31 age- and BMI-matched autopsy cases without PC (controls, 12 with DM). Tumor-free pancreatic sections were stained for insulin and glucagon, and fractional beta cell (BCA) and alpha cell area (ACA) were quantified. In addition, expression of de-differentiation markers, i.e., ALDH1A3 and UCN3, was qualitatively evaluated. The pancreas of subjects with PC showed atrophic and fibrotic changes. There was no significant difference in BCA in subjects with PC compared to controls (1.53 ± 1.26% vs. 0.95 ± 0.42%, p = 0.07). However, ACA and ACA to BCA ratio were significantly higher in subjects with PC compared to controls (2.48 ± 2.39% vs. 0.53 ± 0.26% and 1.94 ± 1.93 vs. 0.59 ± 0.26, respectively, both p < 0.001). Increased ACA to BCA ratio was observed in subjects with PC irrespective of the presence of DM. Qualitative evaluation of ALDH1A3 and UCN3 expression showed no significant difference between the groups. In conclusion, in subjects with PC, alpha to beta cell mass ratio is increased, which may contribute to the increased risk of worsening glucose metabolism. Further studies are warranted to elucidate the mechanisms of increased alpha to beta cell mass in patients with PC.


Asunto(s)
Diabetes Mellitus , Células Secretoras de Glucagón , Células Secretoras de Insulina , Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/complicaciones , Insulina , Neoplasias Pancreáticas
4.
Health Commun ; 37(12): 1520-1533, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35505456

RESUMEN

This study quantitatively examines whether health literacy can reduce belief in COVID-19 misinformation and conspiracy theories. Conducting path and cluster analyses on survey data collected from 1,488 adults in Japan in 2021, we found that while health literacy reduces people's belief about COVID-19 and vaccination misinformation, it has no direct effect on their belief in COVID-19 conspiracy theories. That said, the results also highlighted the importance of health literacy. It is found that even though high health literacy does not guarantee a low degree of conspiracy beliefs, low health literacy is associated with high susceptibility to both misinformation and conspiracy theories. Moreover, people who relied more on social media than mass media for COVID-19 news and reported on having been more severely affected by the pandemic were found to be more likely to have lower health literacy and higher belief in misinformation and conspiracy theories. Based on the findings, we discussed ways to enhance health literacy research and promotion in Japan.


Asunto(s)
COVID-19 , Alfabetización en Salud , Adulto , COVID-19/epidemiología , Humanos , Infodemia , Japón/epidemiología , SARS-CoV-2
5.
Diabetologia ; 64(8): 1816-1821, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33938968

RESUMEN

AIMS/HYPOTHESIS: Type 2 diabetes is characterised by reduced beta cell mass (BCM). However, it remains uncertain whether the reduction in BCM in type 2 diabetes is due to a decrease in size or number of beta cells. Our aim was to examine the impact of beta cell size and number on islet morphology in humans with and without type 2 diabetes. METHODS: Pancreas samples were obtained from 64 Japanese adults with (n = 26) and without (n = 38) type 2 diabetes who underwent pancreatectomy. Using pancreatic tissues stained for insulin, we estimated beta cell size based on beta cell diameter. Beta cell number was estimated from the product of fractional beta cell area and pancreas volume divided by beta cell size. The associations of beta cell size and number with islet morphology and metabolic status were examined. RESULTS: Both beta cell size (548.7 ± 58.5 vs 606.7 ± 65.0 µm3, p < 0.01) and number (5.10 × 108 ± 2.35 × 108 vs 8.16 × 108 ± 4.27 × 108, p < 0.01) were decreased in participants with type 2 diabetes compared with those without diabetes, with the relative reduction in beta cell number (37%) being greater than for beta cell size (10%). Beta cell number but not size was positively correlated with BCM in participants with and without type 2 diabetes (r = 0.97 and r = 0.98, both p < 0.01) and negatively correlated with HbA1c (r = -0.45, p < 0.01). CONCLUSIONS/INTERPRETATION: Both beta cell size and number were reduced in participants with type 2 diabetes, with the relative reduction in beta cell number being greater. Decrease in beta cell number appears to be a major contributor to reduced BCM in type 2 diabetes.


Asunto(s)
Recuento de Células , Tamaño de la Célula , Diabetes Mellitus Tipo 2/patología , Células Secretoras de Insulina/patología , Anciano , Cromatografía Líquida de Alta Presión , Diabetes Mellitus Tipo 2/sangre , Femenino , Hemoglobina Glucada/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Pancreatectomía
6.
Zookeys ; (636): 51-65, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27917064

RESUMEN

The pygidicranid earwigs (Dermaptera) of Penang Island, Peninsular Malaysia were re-examined based on material collected in extensive field surveys in 2012-2013 and 2015. Echinosoma roseiventre Kamimura & Nishikawa, sp. n. is described and illustrated, and Cranopygia pallidipennis (de Haan, 1842) is reported from the island for the first time. The taxonomic and nomenclatural problems of the genus Cranopygiasensu Hincks (1959) [A Systematic Monograph of the Dermaptera of the World. Part II. Pygidicranidae excluding Diplatyinae. British Museum (Natural History)] are also discussed. For the members of the subfamily Pygidicraninae from Indo-Austral and Oriental regions, the system, definitions of genera, and key of Hincks (1959) are followed. The genus Mucrocranopygia Steinmann, 1986 is synonymized with Cranopygia Burr, 1908. A key to the males of small Echinosoma from the Oriental region is provided.

7.
Zootaxa ; 4084(2): 233-57, 2016 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-27394261

RESUMEN

The earwig (Dermaptera) fauna of Penang Island, Malaysia, was evaluated by means of an extensive field survey together with revision of the few published data. Based on the results of the field survey, 31 species are recognized (2 Diplatyidae, 3 Pygidicranidae, 5 Anisolabididae, 2 Labiduridae, 14 Spongiphoridae, 4 Chelisochidae, 1 Forficulidae). Fifteen of these taxa are new to Peninsular Malaysia (=West Malaysia): Diplatys annandalei Burr, 1911, Diplatys mutiara n. sp., Euborellia philippinensis Srivastava, 1979, Metisolabis punctata (Dubrony, 1879), Pseudovostox brindlei Srivastava, 2003, Chaetospania anderssoni Brindle, 1971, Chaetospania javana Borelli, 1926, Chaetospania huisiangi n. sp., Paralabellula boettcheri (Borelli, 1923), Paralabellula rotundifrons (Hincks, 1954), Nesogaster amoenus (Stål, 1855), Hamaxas crassus Borelli, 1926, Proreus coalescens (Borelli, 1927), Hypurgus humeralis (Kirby, 1891), and an unidentified Echinosoma sp. Species composition of the island are compared with the dermapteran fauna of Thailand. Descriptions of females (or female genitalia) are given for some species for the first time.


Asunto(s)
Insectos/clasificación , Distribución Animal , Estructuras Animales/anatomía & histología , Estructuras Animales/crecimiento & desarrollo , Animales , Tamaño Corporal , Ecosistema , Femenino , Insectos/anatomía & histología , Insectos/crecimiento & desarrollo , Malasia , Masculino , Tamaño de los Órganos
8.
J Phys Chem B ; 118(8): 2164-71, 2014 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-24490849

RESUMEN

Changing pressure from 1 to 2500 bar continuously tunes free energy changes for electron attachment to molecules in nonpolar liquids by nearly 0.3 eV. Rate constants for electron attachment to substituted benzoquinones were determined over an extended free energy range of nearly 1 eV by a combination of solute, pressure, temperature, and use of solvents with differing energies of the quasifree electron, V0: tetramethylsilane (TMS) and 2,2,4-trimethylpentane (TMP). The rates of attachment to both benzoquinone (BQ) and 2,5-dichlorobenzoquinone in TMS increase as the pressure increases to 2500 bar, while in TMP the rates are higher but change little with pressure; the rate of attachment to fluoranil in TMS is similarly high at 1 bar but decreases with increasing pressure. Together the observed rate constants can be qualitatively interpreted to yield a rate vs free energy relation having both normal and Marcus inverted region behavior. Because the electron attachment reactions yield excited states, quantitative interpretation of the free energy dependence requires knowledge of the excited state energies. The electron enters the second lowest π* orbital to form a π*-π* excited state, which quickly relaxes to the lower n-π* excited state. The rate of attachment to this excited state is low when the free energy of reaction, ΔG°, is positive and increases as ΔG° decreases until near -0.2 eV, after which the rate decreases. While excited state energies are uncertain, reasonable estimates are obtained from absorption, excitation, and fluorescence spectra of the product radical anions measured here. The results are modeled using Marcus theory with inclusion of a high frequency molecular vibration.

9.
J Chem Phys ; 127(1): 014504, 2007 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-17627357

RESUMEN

Excess electrons were generated in supercritical krypton by means of pulsed x-ray irradiation, and the electron transport phenomena were studied. Electron signals immediately after a 30 ps pulse showed a distinctive feature characteristic of the presence of the Ramsauer-Townsend minimum in the momentum transfer cross section. The dependence of the drift velocity v(D) on field strength was found to be concave upward in the low field region and then to go through a maximum with increasing field strength, which is also typical of the presence of a minimum in the scattering cross section at an intermediate field strength. A minimum in the electron mobility was observed at about one-half the critical density. The acoustical phonon scattering model, which successfully explained the mobility change in this density region in supercritical xenon, was again found to account for the mobility in supercritical krypton.

10.
J Phys Chem B ; 111(24): 6684-9, 2007 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-17567095

RESUMEN

The attachment of electrons to pyrazine occurs reversibly over a wide range of pressures at and above room temperature in supercritical xenon. The rate constant for attachment increases with pressure at low pressures, passes through a maximum, and levels off at values of 1-3x10(12) m(-1) s(-1) at high pressure. The activation volumes for attachment (DeltaVa*) are quite small but show maxima near the compressibility maxima. In contrast, DeltaVa* is always negative for this reaction in sc-ethane and exhibits minima near the compressibility maxima. The rate constants for electron detachment change little with pressure but increase with temperature. Activation volumes for detachment are small. To explain the small volume change observed for this reaction, it is proposed that at the higher pressures clustering around the neutral pyrazine is comparable to that around the ion; i.e., the partial molar volumes are comparable. The free energy change (DeltaGr) of this reaction decreases between 40 and 60 bar and then is fairly constant at higher pressures. The dependence of DeltaGr on pressure is consistent with clustering around the neutral pyrazine at higher pressure. Also, the electron affinity of the clusters, pyrazineXen, increases with n to a few tenths of an eV.

11.
J Phys Chem B ; 109(7): 2478-86, 2005 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-16851245

RESUMEN

This review focuses on the properties and reactions of charged species in supercritical fluids. The techniques of pulse conductivity and transient absorption are used to follow the behavior of charged species. We begin with a discussion of the mobilities, yields, and energy levels of electrons. Studies of the pressure dependence of electron attachment reactions lead to information on the magnitude of activation volumes. This as well as diffusion and energetics are factors that influence the rates of electron attachment. The free energy changes in electron attachment-detachment equilibrium reactions decrease rapidly at pressures where the compressibility maximizes. The transport properties of ions in supercritical fluids are also discussed, as these studies provide a straightforward indication of the degree of interaction between ions and the medium. We conclude with a review of electron transfer reactions in supercritical fluids.

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