Anatomic variation of a duplicated uterine artery.

During the anatomical dissection of the pelvis, a duplication of the uterine artery was identified unilaterally on the left side in a 59-year-old Korean female cadaver. The first uterine artery was found to arise directly from the anterior division of the internal iliac artery and supply the upper uterine body and tube. The second uterine artery shared a common stem with the superior and inferior vesical arteries, supplying the lower uterine body. The external diameter of each uterine artery at its origin on the left side was smaller than that of the right uterine artery. One vaginal artery was identified to arise from the left internal pudendal artery. Embryologically, a duplicated uterine artery could imply the presence of two primordial arteries separately supplying the cranial and caudal parts of the Müllerian duct during the early fetal period. This case of variational anatomy is noteworthy: clinicians could elucidate it and successfully perform uterine artery embolization or hysterectomy with minimal complications.

Regression analysis of nasal shape from juvenile to adult ages for forensic facial reconstruction.

The nose is a prominent feature for facial recognition and reconstruction. To investigate the relationship of the nasal shape with the piriform aperture in Korean adults and juveniles, we performed regression analysis. By regression analysis, prediction equations for nasal shape were obtained in relation to the shape of the piriform aperture considering sex and age groups. Three-dimensional skull and face models, rendered from computed tomography images, were assessed (331 males and 334 females). Juveniles (<20 years) were divided into three age groups according to the development of the dentition. Adults were divided into three age groups of two decades each, according to their age. To measure the nasal area, nine landmarks and nine measurements were chosen, while seven landmarks and five measurements were selected to measure the piriform aperture area. Four measurements were defined to explain the direct relationship between the nasal aperture and nasal shape. First, descriptive statistical analyses were performed according to sex and age groups. Subsequently, the correlation of nasal soft tissue measurements with piriform measurements was analyzed. Last, we performed a linear regression analysis of the measurements with higher correlations, considering sex and age groups as variables. Prediction equations were used to estimate the nasal bridge length, height, protrusion, and width. Equations considering sex and age groups showed better explanation ability. Measurements related to the height of the nasal bridge presented improvement. This study may assist in the more accurate approximation of nasal shape in facial reconstruction.

Microplastics in gastrointestinal tracts of gentoo penguin (Pygoscelis papua) chicks on King George Island, Antarctica.

Microplastics (< 5 mm) have been found in marine ecosystems worldwide, even in Antarctic ecosystems. In this study, the stomach and upper intestines of 14 dead gentoo penguin (Pygoscelis papua) chicks were collected and screened for microplastics on King George Island, a gateway to Antarctic research and tourism. A total of 378 microplastics were identified by Fourier-transform infrared spectroscopy, with 27.0 ± 25.3 microplastics per individual. The detected number of microplastics did not increase with the mass of penguin chicks, suggesting no permanent accumulation of microplastics. However, the concentration of microplastics was much higher (9.1 ± 10.8 microplastics per individual within the size range 100-5000 µm) than the previously reported concentration in the penguin feces, and a greater number of smaller microplastics were found. Marine debris surveys near the breeding colony found various plastic (79.3%) to be the most frequent type of beached debris, suggesting that local sources of marine plastic waste could have contributed to microplastic contamination of penguin chicks being fed by parents that forage in nearby seas. This finding confirms the presence of microplastics in an Antarctic ecosystem and suggests the need for stronger waste management in Antarctica and a standardized scheme of microplastic monitoring in this once-pristine ecosystem.

Forest microclimate and composition mediate long-term trends of breeding bird populations.

Climate change is contributing to biodiversity redistributions and species declines. However, cooler microclimate conditions provided by old-growth forest structures compared with surrounding open or younger forests have been hypothesized to provide thermal refugia for species that are sensitive to climate warming and dampen the negative effects of warming on population trends of animals (i.e., the microclimate buffering hypothesis). In addition to thermal refugia, the compositional and structural diversity of old-growth forest vegetation itself may provide resources to species that are less available in forests with simpler structure (i.e., the insurance hypothesis). We used 8 years of breeding bird abundance data from a forested watershed, accompanied with sub-canopy temperature data, and ground- and LiDAR-based vegetation data to test these hypotheses and identify factors influencing bird population changes from 2011 to 2018. After accounting for imperfect detection, we found that for 5 of 20 bird species analyzed, abundance trends tended to be less negative or neutral at sites with cooler microclimates, which supports the microclimate buffering hypothesis. Negative effects of warming on two species were also reduced in locations with greater forest compositional diversity supporting the insurance hypothesis. We provide the first empirical evidence that complex forest structure and vegetation diversity confer microclimatic advantages to some animal populations in the face of climate change. Conservation of old-growth forests, or their characteristics in managed forests, could help slow the negative effects of climate warming on some breeding bird populations via microclimate buffering and possibly insurance effects.

Anatomical classification of middle rectal arteries regarding detailed vasculature patterns.

This study aimed to clarify the anatomy of middle rectal artery and pelvic vasculature patterns, and to provide schematic information in a manner applicable to the total mesorectal excision. Forty sides of pelvis from 20 formalin-embalmed cadavers (10 male, 10 female) were dissected, and all the pelvic vasculatures from the internal iliac artery were investigated, focusing on the middle rectal artery. Middle rectal arteries were classified into major types depending on their vascular origins. Each type was subdivided into minor types according to variability of the pelvic vasculature. A middle rectal artery was identified in 18 out of 20 cadavers, and in 25 out of 40 pelvic sides. In most cases, the middle rectal artery originated from the internal pudendal artery or inferior gluteal artery. These two arteries arose directly from the anterior trunk of the internal iliac artery or were bifurcated from the gluteal-pudendal trunk. In rare cases, these arteries arose from the posterior trunk of the internal iliac artery. The other origins of the middle rectal artery included the gluteal pudendal trunk, inferior vesical artery, internal iliac artery, obturator artery, and the prostatic artery, and the pelvic vasculatures in these cases also presented variability. The detailed anatomical findings related to the middle rectal artery and pelvic vasculatures are noteworthy for their improved clinical applicability.

Morphologic classification and innervation patterns of the pectineus muscle.

The purpose of this study was to identify the frequency of pectineal hiatus and of pectineus innervations, including femoral, obturator, and/or accessory obturator nerves. Also, this study sought to detailed intramuscular nervous distributions, with a particular focus on the relationship of nerves in multi-innervated pectineus. One hundred (49 right and 51 left) thighs from 52 cadavers (25 men and 27 women) were dissected. The morphology and innervations of the pectineus were investigated. Modified Sihler's whole-mount nerve-staining method was employed for visualization of the intramuscular nerve-distribution patterns of the pectineus. Variation of the pectineus forming a hiatus was identified in 18% of the specimens. The femoral innervations to the pectineus were identified in all specimens. Additional innervation either by the obturator or the accessory obturator branch to the pectineus was identified in 10% or 2% of specimens, respectively. No case of triple innervation to the pectineus was observed. In cases of dually innervated pectineus, two nerves formed a communication system inside the muscle. Among the three nerves supplying the pectineus, the femoral nerve branched more than the other two nerves and covered the greatest area in the muscle. The pectineal hiatus appears to be a common variation. The femoral nerve branch in a dually innervated pectineus is the dominant nerve component that supplies the muscle when considering frequency, branching pattern, and area, even though cooperation between two nerve components is implied. This study serves to advance the existing anatomical knowledge about the pectineus muscle, which is of clinical value.

When are hypotheses useful in ecology and evolution?

Research hypotheses have been a cornerstone of science since before Galileo. Many have argued that hypotheses (1) encourage discovery of mechanisms, and (2) reduce bias-both features that should increase transferability and reproducibility. However, we are entering a new era of big data and highly predictive models where some argue the hypothesis is outmoded. We hypothesized that hypothesis use has declined in ecology and evolution since the 1990s, given the substantial advancement of tools further facilitating descriptive, correlative research. Alternatively, hypothesis use may have become more frequent due to the strong recommendation by some journals and funding agencies that submissions have hypothesis statements. Using a detailed literature analysis (N = 268 articles), we found prevalence of hypotheses in eco-evo research is very low (6.7%-26%) and static from 1990-2015, a pattern mirrored in an extensive literature search (N = 302,558 articles). Our literature review also indicates that neither grant success nor citation rates were related to the inclusion of hypotheses, which may provide disincentive for hypothesis formulation. Here, we review common justifications for avoiding hypotheses and present new arguments based on benefits to the individual researcher. We argue that stating multiple alternative hypotheses increases research clarity and precision, and is more likely to address the mechanisms for observed patterns in nature. Although hypotheses are not always necessary, we expect their continued and increased use will help our fields move toward greater understanding, reproducibility, prediction, and effective conservation of nature.

Changes in the phosphorylation of nucleotide metabolism­associated proteins by leukemia inhibitory factor in mouse embryonic stem cells.

Leukemia inhibitory factor (LIF) is a stem cell growth factor that maintains self­renewal of mouse embryonic stem cells (mESCs). LIF is a cytokine in the interleukin­6 family and signals via the common receptor subunit gp130 and ligand­specific LIF receptor. LIF causes heterodimerization of the LIF receptor and gp130, activating the Janus kinase/STAT and MAPK pathways, resulting in changes in protein phosphorylation. The present study profiled LIF­mediated protein phosphorylation changes in mESCs via proteomic analysis. mESCs treated in the presence or absence of LIF were analyzed via two­dimensional differential in­gel electrophoresis and protein and phosphoprotein staining. Protein identification was performed by matrix­assisted laser desorption/ionization­time of flight mass spectrophotometry. Increased phosphorylation of 16 proteins and decreased phosphorylation of 34 proteins in response to LIF treatment was detected. Gene Ontology terms enriched in these proteins included 'organonitrogen compound metabolic process', 'regulation of mRNA splicing via spliceosome' and 'nucleotide metabolic process'. The present results revealed that LIF modulated phosphorylation levels of nucleotide metabolism­associated proteins, thus providing insight into the mechanism underlying LIF action in mESCs.

The ascending branch of the lateral circumflex femoral artery penetrating the posterior division of the femoral nerve.

Understanding anatomic variations in neurovascular structure inside the femoral triangle is crucial for regional anesthesiologists performing femoral nerve block. During routine dissection of a cadaver, an ascending branch of the lateral circumflex femoral artery with an anomalous course passing through the femoral nerve, specifically the posterior division, was identified inside the femoral triangle on the left thigh. The novel variation identified in this study occurred in an early stage of prenatal development. Recognition of this anatomic variation will be helpful for reducing unexpected complications during the femoral nerve block and the tensor fascia latae flap. Penetration of the posterior division of the femoral nerve by the arterial branch might cause pain or paresthesia of the medial aspect of the leg in the distribution of the saphenous nerve.

Variation of pectineus muscle forming a hiatus.

Knowledge of the anatomic variations in the pectineus muscle is important for vascular surgeons to minimize complications following surgical approach to the distal part of the deep femoral artery. During routine dissection of the thigh, variations in the bilateral pectineus muscles were identified in an 82-year-old male cadaver. On both sides, the superficial and deep layers of the pectineus were divided at its distal part, forming a triangular-shaped hiatus between them and the femur shaft. Distally, the tendon of the superficial part intermingled with the tendon of the adductor longus. The tendon of the deep part was inserted into the pectineal line. On the right side, the deep femoral artery and its first perforating artery passed through the hiatus. On the left side, the deep femoral artery pierced the hiatus, and then, the first perforating artery was branched from the deep femoral artery. No reported case has described a pectineal hiatus. The variations observed in this study are an ontogenetic vestige of the two different origins of the pectineus. The insertion of the superficial layer into the adductor longus tendon suggests a close relationship between these muscles during prenatal development. Surgeons should be aware of the variation to minimize injury to the pectineus muscle while approaching the deep femoral artery.

Application of nasal profile estimation methods for Korean population.

The nose is an important facial feature that affects facial reconstruction quality and its recognition. We reviewed a selection of papers that researched the nose with regression analysis and applied their regression formulae to our sample to compare the estimated value and measurements. One-hundred computed tomography (CT) scans of Korean adults were selected for this study. The subjects were patients without head trauma, severe deformities, or asymmetry at St. Mary's Hospital in Seoul, Korea. Three dimensional (3D) models of the cranium and face were remodelled and measured by Mimics 14.1 (Leuven, Belgium, Materialise). A measurement system for 3D models that referred to landmarks from previous studies was used to facilitate the comparison process. Estimation formulae were applied to the subjects and compared with the measurement results of this study's population. Corresponding measurements showed that the measurements were statistically significantly different from estimated values obtained with regression formulae. A difference in the results was expected because of the different sample population, but the age of subjects could also impact the results and cause variability. Therefore, the results of this study emphasise the necessity of basal research for a specific target population.

Changes in Emberiza bunting communities and populations spanning 100 years in Korea.

The rapid decline of a few Emberiza bunting species is increasing conservation concerns, especially in Asia. However, temporal changes in communities and populations of buntings, ones of the most common migratory songbirds in Korea, have not been quantitatively assessed. To understand how the status of buntings has changed over the past 100 years, we collated abundance data from museum collections and bird-banding records between 1910 and 2019. We also used presence-absence data for buntings collected by a nationwide census scheme between 1997 to 2012. Our analysis showed that bunting communities reconstructed from museum-specimen and bird-banding data were not significantly different; however, community composition differed over time. The Meadow (E. cioides), Yellow-throated (E. elegans), Black-faced (E. spodocephala), Rustic (E. rustica) and Chestnut Buntings (E. rutila), which are still common or were once common species, significantly affected the temporal changes in bunting community composition. There were no recent changes in the presence of Rustic and Chestnut Buntings since 1997, but they caused medium-term changes in the bunting community composition, suggesting that there was a sharp to moderate decline in their numbers in the past. The probability of the presence of six bunting species decreased annually, with the most prominent decline in two common breeders, the Meadow (-2.99%/year) and Yellow-throated Buntings (-1.82%/year). This finding suggests that breeding buntings in Korea are under high pressure, as are the migratory buntings. Moreover, despite its recent population decline, the Yellow-throated Bunting was still a major contributor to the community, suggesting that bunting diversity has also been deteriorating while bunting populations are shrinking. Long-term monitoring schemes across their distribution ranges, international cooperation for identifying major threats and key areas of conservation, and law enforcement against illegal hunting and habitat loss are strongly required to mitigate the on-going decline of buntings in Korea and Asia.

Assessment of nasal profiles for forensic facial approximation in a modern Korean population of known age and sex.

The nose is a valuable facial feature for facial recognition and approximation. We propose the use of regression functions to predict nasal profiles comprising the structures around the piriform aperture using CT-based 3D models. We examined craniofacial reconstruction models acquired from computed tomographic images of Korean adults (188 males and 201 females). Eighteen measurements using 16 craniometric landmarks were measured on 3D craniofacial models. We conducted a descriptive analysis with comparisons according to sex, and simple linear regression analyses to obtain regression functions. Using multiple regression analyses with sex and age as independent variables, multiple regression equations were developed with coefficient of determination R2 ranging from 0.314 to 0.724, meaning that the equations for known sex and age were better for the prediction of nasal profiles than equations that assumed only known sex. These equations are useful and practical for reconstructing nasal profiles in forensic analyses.

Predicting climate-driven shifts in the breeding phenology of Varied Tits (Sittiparus various) in South Korean forests.

Phenological shifts of plants and animals due to climate change can vary among regions and species, requiring study of local ecosystems to understand specific impacts. The reproductive timing of insectivorous songbirds in temperate forests is tightly synchronized with peak prey abundance, and thus they can be susceptible to such shift in timing. We aimed to investigate the effect of future climate change on the egg-laying phenology of the Varied Tit (Sittiparus various), which is common and widely distributed in South Korean forests. We developed the predictive model by investigating their egg-laying dates in response to spring temperatures along geographical gradients, and our model indicated that the tits lay eggs earlier when the average of daily mean and daily maximum temperatures rise. We predicted future shifts in egg-laying dates based on the most recent climate change model published by the Intergovernmental Panel on Climate Change (IPCC), under a scenario with no climate change mitigation and under a scenario with moderate mitigation. Under this outcome, this species might be unable to adapt to rapid climate change due to asynchrony with prey species during the reproductive period. If no mitigation is undertaken, our model predicts that egg-laying dates will be advanced by more than 10 days compared to the present in 83.58% of South Korea. However, even moderate mitigation will arrest this phenomenon and maintain present egg-laying dates. These results demonstrate the first quantitative assessment for the effect of warming temperatures on the phenological response of insectivorous songbirds in South Korea.

Lumbosacral Defects in a 16th-18th-Century Joseon Dynasty Skeletal Series from Korea.

Paleopathological evidence for congenital and degenerative disorders of the lumbosacral vertebrae is informative about ancient individual lifeways and physical conditions. However, very few studies have focused on the paleopathology of the lumbosacral vertebrae in ancient skeletal series from East Asia. One reason for the lack of studies is that skeletal samples from East Asia are typically insufficient in size to represent populations for comparative studies within the continent. Here, we present the first comprehensive analysis of lumbosacral defects in an East Asian human skeletal sample, examining occurrences of spina bifida occulta (SBO), lumbosacral transitional vertebrae (LSTV), and spondylolysis in remains from Joseon tombs dating to the 16-18th centuries in Korea. In this study, we present an alternative methodology for understanding activities of daily life among ancient Koreans through paleopathological analysis.

Spontaneous cervical epidural hematoma causing brown-sequard syndrome.

Spontaneous cervical epidural hematoma (SCEH) is a rare clinical entity and has a varied etiology. Urgent surgical decompression should be done to prevent serious permanent neurologic deficits. We describe a 59-year-old female who presented with Brown-Sequard syndrome due to spontaneous cervical epidural hematoma. Initially, she was misdiagnosed as cerebrovascular accident. Cervical magnetic resonance imaging revealed epidural hematoma to the right of the spinal cord extending from C3 to C6. She later underwent surgical evacuation and had complete restoration of neurologic function. The outcome in SCEH is essentially determined by the time taken from onset of the symptom to operation. Therefore, early and precise diagnosis such as careful history taking and MRI evaluation is mandatory.

Inhibitory effect of GBH on platelet aggregation through inhibition of intracellular Ca2+ mobilization in activated human platelets.

Geiji-Bokryung-Hwan (GBH) was studied on antiplatelet activity in human platelet suspensions. GBH consists of the 5 herbs Cinnamomi Ramulus, Poria Cocos, Mountan Cortex Radicis, Paeoniae Radix, and Persicae Semen, which have been used in herbal medicine for thousands of years for atherosclerosis. The mechanism involved in the antiplatelet activity of GBH in human platelet suspensions was investigated. GBH inhibited platelet aggregation and Ca2+ mobilization in a concentration-dependent manner without increasing intracellular cyclic AMP and cyclic GMP. GBH had no inhibitory effect on thromboxane B2 (TXB2) production in cell-free systems. Collagen-related peptide (CRP)-induced Ca2+ mobilization is regulated by phospholipase C-2 (PLC-gamma2) activation. We evaluated the effect of GBH on tyrosine phosphorylation of PLC-gamma2 and the production of inositol-1,4,5-trisphosphate (IP3). GBH at concentrations that inhibited platelet aggregation and Ca2+ mobilization had no effects on tyrosine phosphorylation of PLC-gamma2 or on the formation of IP3 induced by CRP. Similar results were obtained with thrombin-induced platelet activation. GBH inhibited platelet aggregation and Ca2+ mobilization induced by thrombin without affecting the production of IP3. We then evaluated the effect of GBH on the binding of IP3 to its receptor. GBH at high concentrations partially blocked the binding of IP3 to its receptor. Therefore, the results suggested that GBH suppresses Ca2+ mobilization at a step distal to IP3 formation. GBH may provide a good tool for investigating Ca2+ mobilization.