We investigated the food composition of the Southeast Asian Rhacophorid frog species Polypedates leucomystax, an invasive species introduced to Okinawajima in the Ryukyu Archipelago, during their ...breeding activities and the month immediately after that. We examined the stomach contents of 190 males and 54 females, uncovering 215 prey items (including at least 56 species) from 113 males and 21 females. The rate of empty stomachs was relatively high, 45.1% for all frogs (40.5% for males and 61.1% for females). Most prey were arboreal, with a minority being obligately terrestrial or aquatic. Insects constituted the majority of the diet (61.4%), followed by other arthropods, gastropods, and a vertebrate (an agamid lizard neonate). Orthopterans were the dominant prey group in terms of number (29.8%), frequency of occurrence (43.3%), and volume (51.6%). This species is considered an opportunistic feeder, a conclusion corroborated by comparisons with locally varied dietary data from populations of conspecific or closely related species in Southeast Asia. The average prey length was approximately one-third of the body length, but instances of the consumption of larger prey were observed. Similarly, males are able to swallow prey up to two-thirds of their gape width and females up to one-third. The data obtained in this study cover most of the active season of this species on the island, and thus provide a basis for elucidating the ecological impact of this species.
The diet of the nonnative American Bullfrog Lithobates catesbeianus occurring in Ogimi Village of Okinawajima, Ryukyu Archipelago, is investigated. Seventy two of 89 frogs (nine adults, five ...subadults, and 58 juveniles) captured had food items in its stomach. We identified a total of 64 taxa from 253 food items. Our analyses show that (1) the diet consists mainly of terrestrial prey, (2) mollusks and vertebrates are the essential prey groups for adults and subadults, and (3) odonates, mollusks, and arachnids are the main prey for juveniles. Such dietary habits are quite different from those of several conspecific nonnative populations in mainland Japan and other regions. Part of this is most likely related to the absence of the frog's favorite prey, nonnative American crayfish Procambarus clarkii, in the study area. We also confirm the predation of a poisonous newt Cynops ensicauda popei (Salamandridae) and several aquatic insects by this frog and present some implications for these results.
The family Rhacophoridae, including Buergeria japonica, shows a great diversity of reproductive patterns, but the knowledge of developmental processes is still limited. The genus Buergeria is a ...sister group to all other rhacophorids and shows a conservative, probably primitive, reproductive mode for this family. Thus, it is valuable to clarify the developmental process in this genus for understanding the evolution and diversification history of reproductive modes and developmental processes across the broader family members. In this study, we describe the normal development of B. japonica by rearing eggs and larvae under ambient temperatures of 27±1°C. The developmental speed of B. japonica from fertilization to gill elongation (stage 20), corresponding to their hatching period, was faster than most of other anuran species, when comparison was made using relative age, which is independent of temperature. The rapid embryonic development may be advantageous in their highly fluctuating breeding environment.
Buergeria japonica, long thought to be a single species widely occurring on the Ryukyu Archipelago and Taiwan, proved to include three genetically differentiated clades, (1) the Northern and Central ...Ryukyu, (2) the Southern Ryukyu and Northern Taiwan, and (3) the Southern Taiwan clades. The Southern Taiwan clade has already been split from the others as a distinct species. A distinct heterospecific relationship of the Southern Ryukyu and Northern Taiwan clade from the Northern and Central Ryukyu clade was also clear from genetic evidence. Morphological comparison between specimens from the Yaeyama (the Southern Ryukyu and Northern Taiwan clade) and Amamioshima, the type locality of B. japonica (the Northern and Central Ryukyu clade), confirmed genetic differences and corroborate their independent species status. Thus, we describe the Northern Taiwan and Southern Ryukyu clade as B. choui sp. nov.
A Japanese microhylid, Microhyla okinavensis, originally described from Okinawajima Island, middle Ryukyus, was long synonymized with M. ornata from India. However, molecular phylogenetic studies ...revealed its distinct species status from M. ornata, and more recent phylogenetic study revealed the population from the Yaeyama Group of the southern Ryukyus to be a sister taxon to Chinese M. mixtura and not to populations from the remaining group of the Ryukyus, that are sister to another Chinese species, M. beilunensis. The Yaeyama and the remaining Ryukyu populations greatly differ phylogenetically, although less clearly morphologically. From these data, we consider the Yaeyama population as a species distinct from M. okinavensis from the middle Ryukyus.
Rathke's cleft cysts (RCCs) are relatively common and often detected incidentally. They are usually asymptomatic and managed conservatively. However, little is known about their natural history. ...Thus, the authors aimed to examine the natural course of RCCs and identify the risk factors for their progression.
This retrospective study examined 229 patients (median age 43.0 years) diagnosed with RCCs by MRI and followed up without surgery (median period 36.6 months). The median cyst height on the initial MRI was 10 mm. Progression or regression of RCC was defined as cyst height changes of ≥ 1 mm.
In total, 23 (10.0%) RCCs progressed, whereas 73 (31.9%) RCCs spontaneously regressed. The remaining 133 were noted to be stable throughout the follow-up period. Patients with progressed RCCs were significantly older than those with stable RCCs. In patients with acute headache as an initial symptom, RCCs were significantly more likely to spontaneously regress. New symptoms occurred in 6 patients, 5 of whom underwent surgery for RCC progression. Of these 6 patients, 1 patient had persistent adrenocorticotropic hormone deficiency and 1 patient developed diabetes insipidus. Kaplan-Meier analysis results showed RCC progression and new symptom development rates to be 12.0% and 4.1% at 5 years and 13.7% and 5.7% at 10 years, respectively.
RCCs rarely progress or cause new symptoms in the long term. Patients with asymptomatic RCC should be followed up for at least 5 years to ensure RCC inactivity. RCCs in older adults may require greater surveillance.
Recovery from adult growth hormone deficiency (AGHD) after transsphenoidal surgery (TSS) has not been well discussed because of the lack of examinations including pituitary provocation tests (PPTs) ...before and after the procedure. This study aimed to evaluate the growth hormone (GH) axis function of patients with nonfunctioning pituitary adenoma (NFPA) via pre- and postoperative PPTs. Moreover, the predictive factors for recovery from AGHD after TSS were validated to facilitate surgery for AGHD in patients with NFPA.
In total, 276 patients (median age 60.0 years) who underwent TSS for NFPA were included in this study. PPTs were performed before and 3 months after TSS. Then, the relationships between recovery from AGHD after TSS and clinical, surgical, and hormonal factors, including peak GH level based on PPTs, were evaluated statistically.
In this study, 114 patients were diagnosed with preoperative AGHD. Approximately 25.4% recovered from AGHD after TSS. In contrast, among the 162 patients without preoperative AGHD, 13 (8.0%) had newly developed postoperative AGHD. The predictive factors for recovery from AGHD were younger age, female sex, initial TSS, and high peak GH level based on preoperative PPT. According to the receiver operating characteristic curve analysis, patients who were aged ≤ 62.2 years and had a peak GH level of ≥ 0.74 μg/L based on preoperative PPT were likely to recover from AGHD (sensitivity: 82.8%, specificity: 72.9%, and area under the curve: 0.8229).
AGHD caused by NFPA can improve after initial TSS among young patients with certain peak GH levels assessed by preoperative PPT. Whether TSS for NFPA can promote recovery from AGHD is worth considering in some patients.
Purpose
Diabetes insipidus (DI) following transsphenoidal surgery (TSS) is a common complication. Although postoperative DI often occurs in patients with craniopharyngioma and Rathke’s cleft cyst, ...postoperative DI in patients with non-functioning pituitary adenoma (NFPA) has not been fully examined. We clarified the clinical characteristics and magnetic resonance imaging (MRI) findings predicting postoperative DI in NFPAs.
Methods
A total of 333 patients undergoing initial TSS for NFPA were included in this retrospective study. Hyperintensity (HI) in the posterior pituitary lobe was evaluated on preoperative T1-weighted MRI. Based on the findings of HI patients were divided into three groups as follows: HI was not detected (Disappearance group), HI located intrasellarly (Intrasellar group), and HI located suprasellarly (Suprasellar group).
Results
The overall rate of DI was 21.9%, including permanent DI in 0.6%. DI occurred at postoperative day 1 (72.6%) or day 2 (19.2%) and improved within 7 days in most cases (87.7%). Univariable and multivariable analyses showed that the predictive factors of DI were a younger age (odds ratio OR 0.97, 95% confidence interval CI 0.95–0.99,
P
= 0.0037) and larger tumor diameter (OR 1.04, 95% CI 1.01–1.08,
P
= 0.0155). The rate of DI was highest in the Disappearance group (43.8%) followed by the Intrasellar group (26.0%). The OR was 2.17 in the Intrasellar group compared with the Suprasellar group (95% CI 1.17–4.02,
P
= 0.0141).
Conclusions
Factors predicting DI following TSS for NFPA were a younger age, larger tumor size, and the location of intrasellar HI on preoperative T1-weighted MRI.
A crocodile newt, Echinotriton raffaellii, recently described from the Amami islands in the Ryukyu archipelago, western Japan has been regarded as Amami lineage of E. andersoni from the Okinawa ...islands, to which it is morphologically very similar, but genetically divergent. In the original description of E. raffaellii, only two specimens, including one born in captivity, were examined and only limited morphological comparisons with E. andersoni were made. Here we examined the morphological characteristics of E. raffaellii with an ample set of specimens, compared them with those of E. andersoni, and clarified their independent specific statuses.
Abstract
Discrepancies in geographic variation patterns between nuclear DNA and mitochondrial DNA (mtDNA) are the result of the complicated differentiation processes in organisms and are the key to ...understanding their true evolutionary processes. The genetic differentiation of the northern and Southern-Izu lineages of the Japanese newt, Cynops pyrrhogaster, was investigated through their single nucleotide polymorphism variations obtained via multiplexed ISSR genotyping by sequencing (MIG-seq). We found three genetic groups (Tohoku, N-Kanto and S-Kanto), that were not detected by mtDNA variations, in the northern lineage. N-Kanto has intermediate genetic characteristics between Tohoku and S-Kanto. The genetic groups are now moderately isolated from each other and have unique genetic characteristics. An estimation of the evolutionary history using the approximate Bayesian computation (ABC) approach suggested that Tohoku diverged from the common ancestor of S-Kanto and S-Izu. Then, S-Kanto and S-Izu split, and the recent hybridization between Tohoku and S-Kanto gave rise to N-Kanto. The origin of N-Kanto through the hybridization is relatively young and seems to be related to changes in the distributions of Tohoku and S-Kanto as a result of climatic oscillation in the Pleistocene. We conclude that the mitochondrial genome of S-Kanto was captured in Tohoku and that the original mitochondrial genome of Tohoku was entirely removed through hybridization.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
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