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Anti-β2-glycoprotein I/HLA-DR (anti-β2GPI/HLA-DR) antibody has been reported to be associated with antiphospholipid syndrome and recurrent pregnancy loss (RPL). We conducted a prospective multicenter cross-sectional study aimed at evaluating whether the anti-β2GPI/HLA-DR antibody is associated with adverse obstetric outcomes and RPL. From 2019 to 2021, serum anti-β2GPI/HLA-DR antibody levels (normal

Syphilis infection during pregnancy causes perinatal complications and mother-to-child transmission if untreated. A newborn was delivered by emergent cesarean section due to non-reassuring fetal status at 34 weeks of gestation. The mother tested negative for rapid plasma reagin (RPR) and Treponema pallidum hemagglutination (TPHA) in early pregnancy. The newborn had a severe inflammatory reaction, thrombocytopenia, and elevated IgM as well as disseminated intravascular coagulation and multiple organ failure. The 16S ribosomal RNA gene sequence analysis of the amniotic fluid detected Treponema pallidum. The newborn tested positive for RPR, TPHA, and IgM fluorescent treponemal antibody-absorption in the blood, and thus, congenital syphilis was diagnosed. This is the first case that 16S ribosomal RNA gene sequencing of the amniotic fluid led to an early diagnosis of congenital syphilis in a newborn. The 16S rRNA gene sequencing may be a useful method for the early detection of the primary causative microbe of congenital infection.

Milk-derived miR-148a-3p (miR-148a), which is abundant in breast milk, has been shown to be associated with the development of infants' intestines. Although it is well known that stress during lactation changes milk constituents in terms of lipid and protein, no studies have examined the influence of stress on miR-148a expression in breast milk. The objective of this study is to investigate the relationship between stress and miR-148a expression in milk, and to evaluate whether the changes in milk-derived miR-148a expression-caused by the mother's exposure to stress-influence intestinal ZO-1 expression in infants.The participants of this study were healthy Japanese women who were nursing. Psychological stress evaluation of the subjects was conducted using a short form of the Profile of Mood State Second Edition-Adult (POMS-2). Additionally, miR-148a expressions in restraint stressed nursing mice were investigated using quantitative real-time PCR. The levels of a tight junction protein zonula occludens-1 (ZO-1) and DNA methyltransferase 1 (DNMT1), which is a direct target of miR-148a, in ileum in neonatal mice breastfed by stressed nursing mice were investigated using Western blot. Furthermore, to investigate the influence of miR-148a on ZO-1 expression within the intestine, the levels of ZO-1 and DNMT1 in human intestinal epithelial Caco-2 cells with lentivirus-mediated miR-148a overexpression were evaluated.A significantly negative correlation was observed between relative miR-148a expression in breast milk and the total mood disturbance T-score. Each T-score on negative mood subscales of anger-hostility, confusion-bewilderment, depression-dejection, fatigue-inertia, and tension-anxiety was significantly negatively correlated with relative miR-148a expression in breast milk: a positive mood subscale vigor-activity T-score was significantly positively correlated with relative miR-148a expression in breast milk. A positive mood friendliness T-score, estimated separately from other scores, was significantly positively correlated with relative miR-148a expression in breast milk. Additionally, the relative expression of miR-148a in the milk obtained from stressed mice was significantly lower than that of control mice. The relative level of ZO-1 in ileum of neonatal mice nursed by stressed mice was significantly lower than that of neonatal mice nursed by control mice. Additionally, the relative level of DNMT1 in ileum of neonatal mice nursed by stressed mice was significantly higher than that of neonatal mice nursed by control mice. Furthermore, the relative level of ZO-1 in miR-148a-overexpressed Caco-2 cells was significantly higher than that in control cells. The relative level of DNMT1 in miR-148a-overexpressed Caco-2 cells was significantly lower than that in control cells.Mothers' exposure to stress during lactation may cause miR-148a expression in breast milk. Additionally, stressed-induced suppression of miR-148a expression in breast milk may cause a decrease in intestinal ZO-1 level via the increase in DNMT1 in infants' intestines. These observations are beneficial information for breastfeeding mothers and their families and perinatal medical professionals. Our findings encourage monitoring maternal psychological stress during lactation to promote breastfeeding and adequate infant nutrition.

NIR fluorescence imaging using bisphosphonate-Indocyanine green has been indicated for early interproximal caries detection. This study assessed diagnostic accuracy of caries detection by NIR fluorescence imaging with OsteoSense 750® (OS750) in vitro and ex vivo, and to analyze the therapeutic efficacy of a bisphosphonate (Etidronate) in inhibiting enamel caries progression in vitro. Methods: Four experiments were conducted using extracted human teeth; 1) to calculate the infiltration rate of OS750 into interproximal white spot lesions using fluorescence microscope, 2) to assess diagnostic accuracy of interproximal natural white spot lesions using desktop NIR fluorescence imaging device in vitro setting, 3) to assess diagnostic accuracy of artificially created deeper enamel carious lesion (0.5 mm~1.0 mm) using NIR fluorescence image through the head-mount display in ex vivo setting, 4) to compare the progression on the enamel caries lesions treated by Etidronate, NaF and distilled-water. Diagnostic accuracy was analyzed using sensitivity, specificity and receiver operating curves (ROC). The caries progression was calculated with micro-CT and was statistically analyzed using a two-way ANOVA and the Tukey HDS post-hoc test. Results: 1) The infiltration rate of OS750 was 101.83% ± 8.66 (Min: 90.10%, Max: 133.94%). 2) The average of sensitivity and specificity in vitro setting experiments were 86.7% ± 4.4% and 70% ± 11%, respectively. The average of area under the ROC curves (AUC) was 0.883 ± 0.059 indicating excellent performance. 3) The mean sensitivity and specificity in ex vivo setting was 82.97% ± 15% and 76.78% ± 13.27% respectively. 4) The carious lesion volume treated by Etidronate was significantly smaller at post treatment-1 (p

Purpose This study sought to explore whether the experience level of the first assistant surgeon influences perioperative organ injuries (ureteral, bladder, and intestinal injuries) in patients undergoing total laparoscopic hysterectomy (TLH) for benign diseases. We defined an experienced surgeon as a surgeon certified by the Skill Qualification Committee of the Japan Society of Gynecologic and Obstetric Endoscopy and Minimally Invasive Therapy or a surgeon with equivalent surgical skills. Methods We reviewed our surgical registry database of TLH for benign indications between 2014 and 2020 and only selected cases performed by an experienced primary surgeon. Patients were divided into two groups based on the experience level of the first assistant. Inverse probability of treatment weighting by propensity score, which was adjusted for patient and procedure characteristics, was used to examine differences in perioperative organ injuries according to the experience level of the first assistant. Results Among 1682 patients who underwent TLH, 18 organ injuries were found (0.83%). In the propensity score inverse probability of treatment weighting models, less experience of the first assistant had no significant impact on the occurrence of perioperative organ injuries (p = 0.348). Conclusion In TLH for benign indications at our hospital, given an experienced primary surgeon, the inclusion of a less experienced first assistant does not negatively affect the occurrence of perioperative organ injuries.

Sphingosine 1-phosphate (S1P), an inflammatory mediator, is abundantly contained in red blood cells and platelets. We hypothesized that the S1P concentration in the peritoneal cavity would increase especially during the menstrual phase due to the reflux of menstrual blood, and investigated the S1P concentration in the human peritoneal fluid (PF) from 14 non-endometriosis and 19 endometriosis patients. Although the relatively small number of samples requires caution in interpreting the results, S1P concentration in the PF during the menstrual phase was predominantly increased compared to the non-menstrual phase, regardless of the presence or absence of endometriosis. During the non-menstrual phase, patients with endometriosis showed a significant increase in S1P concentration compared to controls. In vitro experiments using human intra-peritoneal macrophages (MΦ) showed that S1P stimulation biased them toward an M2MΦ-dominant condition and increased the expression of IL-6 and COX-2. An in vivo study showed that administration of S1P increased the size of the endometriotic-like lesion in a mouse model of endometriosis.

Background Milk-derived microRNAs (miRNAs), including hsa-miR-148a-3p (miR-148a) and hsa-miR-125b-5p (miR-125b), have been shown to be beneficial to the gastrointestinal function in infants. Here, we investigated their expression during lactation in humans and determined whether the infant formulae available in Japan contain these miRNAs. Methods Healthy Japanese women (n = 16) who gave birth vaginally or by cesarean section at the Teine Keijinkai Hospital between 1 September 2020, and 31 April 2021 were included in this study. Breast milk was collected by nurses on days 4 or 5 after delivery (hereinafter, transition milk) and on day 30 of postpartum (hereinafter, mature milk). The levels of miR-148a and miR-125b in breastmilk and six commercially available infant formulae were compared and evaluated using quantitative reverse transcription-polymerase chain reaction. Results In all participants, the miR-148a level in mature breastmilk was significantly lower than that in the transition milk. The changes in miR-125b expression during lactation showed similar trends to the changes in miR-148a expression. The miR-148a and miR-125b levels in all analyzed infant formulae were lower than 1/500th and 1/100th of those in mature breastmilk, respectively. Conclusions The levels of both miR-148a and miR-125b in human breast milk decreased on day 30 postpartum compared with those in the transition milk. Additionally, the expression of these miRNAs in infant formulae available in Japan was very low. Further studies with larger populations are required to understand precisely the lactational changes in the expression of miR148a and miR-125b in breast milk.

This systematic review aimed to investigate complications related to initial trocar insertion among 3 different laparoscopic techniques: Veress needle (VN) entry, direct trocar entry (DTE), and open entry (OE). A literature search was completed, and complications were assessed. Major vessel injury, gastrointestinal injury, and solid organ injury were defined as major complications. Minor complications were defined as subcutaneous emphysema, extraperitoneal insufflation, omental emphysema, trocar site bleeding, and trocar site infection. Arm-based network meta-analyses were performed to identify the differences in complications among the 3 techniques. Seventeen studies were included in the quantitative analysis. DTE resulted in fewer major complications when compared with VN entry although the difference was not significant (p = .23) as well as significantly fewer minor complications (p < .001). There were no significant differences in minor complications when comparing OE and DTE (p = .74). Fewer major complications were observed with OE compared with VN entry although the difference was not significant (p = .31). There were significantly fewer minor complications for patients who underwent OE (p = .01). DTE patients experienced the least number of minor complications followed by VN entry and OE. In conclusion, major complications are extremely rare, and all 3 insertion methods can be performed without mortality.

This paper describes the amounts and size distributions of amorphous nanoparticles in clays, soils and marine sediments, and the effect of amorphous nanoparticles on the properties of clays, soils and marine sediments. So far aluminum–silicate amorphous nanoparticles such as allophane were observed only in soils of volcanic origin with a transmission electron microscope, and thus most people believed that aluminum–silicate amorphous nanoparticles were present only in soils of special origin. Recently, a method has been devised to quantify amorphous nanoparticles by using small angle X-ray scattering intensity. Using the method, we have quantified amorphous nanoparticles in clays, soils and marine sediments, and have found that all clays, soils and marine sediments measured in this study contain large amounts of amorphous nanoparticles. On the basis of this result, we have concluded that large amounts of amorphous nanoparticles are ubiquitously formed from rocks when the rocks are weathered or altered. We have also found that the amorphous nanoparticles affect the properties of clays, such as adsorption properties and plasticity. These findings show that amorphous nanoparticles play an important role in clays, soils and marine sediments.

In endometriosis, M2 MΦs are dominant in endometriotic lesions, but the actual role of M2 MΦ is unclear. CD206 positive (+) MΦ is classified in one of M2 type MΦs and are known to produce cytokines and chemokines. In the present study, we used CD206 diphtheria toxin receptor mice, which enable to deplete CD206+ cells with diphtheria toxin (DT) in an endometriosis mouse model. The depletion of CD206+ MΦ decreased the total weight of endometriotic-like lesions significantly (p

Aim This study aimed to identify the risk factors for vaginal cuff infection after laparoscopic hysterectomy for benign gynecological diseases. Methods We conducted a retrospective cohort study among 1559 Japanese women who underwent total laparoscopic hysterectomy (TLH) for benign indications between 2014 and 2018 at Teine Keijinkai Hospital in Sapporo, Japan. All patients received preoperative antibiotics based on appropriate timing, choice, and weight-based dosing. We assessed the risk factors of vaginal cuff infection after TLH, including demographic and clinical variables, and patient- and surgery-related factors, using univariable and multivariable logistic regression analyses. Results Among all the patients who underwent TLH, 71 cases of vaginal cuff infections (4.6%) were recorded. Univariate analyses showed that current smoking, pathological result of adenomyosis, use of Seprafilm as an antiadhesive material, white blood cell counts on postoperative day (POD) 2, C-reactive protein (CRP) level on POD2 and postoperative vaginal cuff hematoma were significantly associated with an increased risk of vaginal cuff infection. In multivariate analysis, current smoking, use of seprafilm, CRP level on POD2 and vaginal cuff hematoma were significantly associated with an increased risk of vaginal cuff infection. Conclusion Current smoking, use of seprafilm, CRP level on POD2 and vaginal cuff hematoma were identified as significant risk factors of vaginal cuff infection in the 30 days after surgery in Japanese women who underwent TLH for benign indications.

INTRODUCTION Although various perinatal complications have been reported to be increased in the pregnant patients with adenomyosis, it is not clear what type of patients with adenomyosis is more likely to cause obstetric complications. In this study, we focused on the positional relationship between the placenta and adenomyosis lesion in evaluating perinatal prognosis of pregnant patients with adenomyosis. MATERIAL AND METHODS This retrospective cohort study was carried out between 1 January 2005 and 31 December 2019 in a single institution. Adenomyosis was diagnosed by magnetic resonance imaging (MRI) and/or transvaginal ultrasonography (TVUS). To evaluate the influence of adenomyosis on perinatal outcomes, we classified the positional relationship between the placenta and the adenomyosis lesion into two groups and examined the perinatal prognosis of the patients with adenomyosis by analyzing their clinical records. Group I (n = 9) was defined when the placenta was not overlaid on adenomyosis lesion. Group II (n = 11) was defined when a part of the placenta was overlaid on adenomyosis lesion. RESULTS Twenty pregnant patients with adenomyosis were analyzed. There were no differences in clinical backgrounds between group I and group II. There was a significant increase in the obstetric morbidity in group II than that of Group I(group I: 6.3%, 4/63 vs group II: 18.6%, 26/77; P < 0.001). In group II, fetal growth restriction (FGR) was more frequent (0%, 0/9 vs 45.5%, 5/11; P = 0.042) and the birth weight was significantly lower than that in group I (2951.1 g ± 326.5 g vs 2318.9 ± 656.1 g; P = 0.037). There was a trend of lighter weight of the placenta in group II (550.6 ± 66.5 g vs 437.5 ± 117.8 g; P = 0.063) and the volume of bleeding during delivery was a higher trend in group II than that in group I (845.1 ± 367.1 g vs 1356 ± 604.8 g; P = 0.083). Group II was furtherly subdivided into group IIa (less than half the major axis of the placenta overlaid on adenomyosis lesion) and group IIb (more than half the major axis of placenta overlaid on adenomyosis lesion). The obstetric morbidity tended to be higher in group IIb than in group IIa (group IIa: 22.9%, 8/35 vs group IIb: 42.9%, 18/42); P = 0.09). In group IIb, the frequency of FGR was significantly higher (group IIa: 0%, 0/5 vs IIb: 83.3%, 5/6; P = 0.020) and the birth weight was significantly lower than those in group IIa (2656.8 ± 231.9 g vs 2037 ± 780.1 g; P = 0.040). All cases of FGR, hypertensive disorder of pregnancy (HDP), and oligohydramnios were observed in group IIb. CONCLUSION Placental localization near adenomyosis may increase the risk of perinatal complications.

Background: Relaxin (RLX)-2, produced by the corpus luteum and placenta, is known to be potentially effective in fibrotic diseases of the heart, lungs, kidneys, and bladder, however, its effectiveness in endometriosis has not yet been investigated. In the present study, we conducted a comprehensive study on the effect of RLX-2 on endometriosis. We checked the expressions of LGR-7, a primary receptor of RLX-2, in endometriomas using immunohistochemistry. Endometriotic stromal cells (ESCs) purified from surgical specimens were used in in vitro experiments. The effects of RLX-2 on ESCs were evaluated by quantitative-PCR, ELISA, and Western blotting. Gel contraction assay was used to assess the contraction suppressive effect of RLX-2. The effect of RLX-2 was also examined in the endometriosis mouse model. LGR-7 was expressed in endometriotic lesions. In ESCs, RLX-2 increased the production of cAMP and suppressed the secretion of interleukin-8, an inflammatory cytokine, by 15% and mRNA expression of fibrosis-related molecules, plasminogen activator inhibitor-1 (PAI-1), and collagen-I by approximately 50% (p &lt, 0.05). In the gel contraction assay, RLX-2 significantly suppressed the contraction of ESCs, which was cancelled by removing RLX-2 from the medium or by adding H89, a Protein Kinase A (PKA) inhibitor. In ESCs stimulated with RLX-2, p38 MAPK phosphorylation was significantly suppressed. In the endometriosis mouse model, administration of RLX-2 significantly decreased the area of the endometriotic-like lesion with decreasing fibrotic component compared to non-treated control (p = 0.01). RLX-2 may contribute to the control of endometriotic lesion by suppressing fibrosis, scar formation, and inflammation.

Aim It is commonly thought that laparoscopic surgery leads to faster postoperative recovery for its low invasiveness. We evaluated postoperative quality of life (QOL) after laparoscopic myomectomy (LM) by using the Euro-QOL 5 dimension (EQ-5D) score and analyzed its relationship to surgical factors. Methods Between 2014 and 2016, 541 patients underwent LM at our institution. We included 86 patients in the final analysis (16% response rate) who replied to the EQ-5D questionnaire, in order to investigate postoperative QOL. We evaluated patients' EQ-5D score before the operation and on the 3rd, 7th, 14th, 21st and 28th postoperative day (POD). We investigated the degree of correlation between the EQ-5D score and four surgical characteristics (operation time, intraoperative bleeding, number of resected myomas and weight of specimen). We examined correlation between EQ-5D scores and chief complaints such as hypermenorrhea, dysmenorrhea, other pain, myoma enlargement, palpable tumor and desire for childbearing. We also examined correlation between EQ-5D scores and other factors such as patient's age, infertility, history of abdominal surgery, marriage and body mass index. Results Full recovery, defined as an EQ-5D score of 1.0, was reported 2.3% of patients by POD3, 18.6% by POD7, 58.1% by POD14, 73.3% by POD21 and 86.0% by POD28. Longer duration of operation correlated weakly with poor recovery on POD3. Intraoperative bleeding, number of resected myomas and weight of the specimen did not significantly influence EQ-5D score. There was no correlation between chief complaints or other factors mentioned above and EQ-5D score. Conclusions More than a half of the patients undergoing LM included in our study reported full recovery of QOL after 2 weeks. The time to recover QOL was slightly influenced by the operation time. However, when LM was finished without any complications, postoperative QOL eventually seemed to improve regardless of the surgical characteristics such as operation time, intraoperative bleeding, number of resected myomas and weight of specimen.

Introduction We investigated whether temporary bilateral laparoscopic uterine artery clipping with hysteroscopic transcervical resection (LUA clipping-TCR) is an effective minimally invasive treatment for the management of cervical pregnancy. Materials and methods : This study is a retrospective clinical case series conducted at Teine Keijinkai Hospital from January 2014 to June 2019. Nine cervical pregnancies among 164 ectopic pregnancies were retrospectively examined. The intervention involved performing LUA clipping-TCR on villous tissue. Information on patient characteristics, clinical data, and surgical details was collected from medical records and surgical videos. Results The mean (range) age of the patients was 33 years (29–41 years); and mean gestational sac diameter, 12.8 mm (5–24 mm). Five patients had a history of intrauterine procedures. Three patients had a positive fetal heartbeat. The mean (range) preoperative serum hCG level (mIU/mL), surgical time (min), uterine artery blocking time (min), and amount of surgical blood loss (ml) were 14,040 (2880–41,367), 82 (62–120), 42 (21–68), and 57 (10–200), respectively. The mean decrease in serum hCG level (second postoperative day) and duration until resumption of menstruation were 79.7 % (70–86.7 %) and 46 days (35–80 days), respectively. The hospitalization period was 2–3 days, with no evidence of persistent ectopic pregnancy. Live birth was achieved in four cases. Discussion Our results confirm previous findings and provide new evidence that LUA clipping-TCR is effective for cervical pregnancy management and fertility preservation, respectively. Future large-scale prospective studies to compare different cervical pregnancy management methods are required.

Aim Postlaparoscopic shoulder pain (SP), mainly caused by pneumoperitoneum with CO2 , sometimes suffers patients. This study was aimed to analyze the backgrounds of SP after gynecologic laparoscopy to clarify the risk of SP. Methods We analyzed answers of questionnaire about the degree of SP from 696 patients undergoing gynecologic laparoscopic surgery since 2014-2018. The questionnaire asks the degree of SP with numeric rating scale from 0 to 10, before and 3 days after operation. We defined cases in which postoperative score elevated more than three compared to preoperative score as SP(+). Analyzed backgrounds were age, parity, body mass index, operative method, operative duration and amount of hemorrhage. Statistics was performed by Fisher exact analysis as univariate analysis, and with logistic regression as multivariate analysis. All laparoscopic surgeries were performed under 10-12 mmHg in pressure of pneumoperitoneum with CO2 . Results Univariate analysis revealed categories 'less than 50 years old', and 'over 2 h' and 'over 3 h' in operative duration resulted significant high rate of SP(+). For these three factors, multivariate analysis resulted that "less than 50 years old' and 'over 3 h in operative duration' were significantly high. Conclusion This study suggests that 'less than 50 years' old and 'over 3 h in operative duration' were risk factors of postlaparoscopic SP. To protect from SP after laparoscopy, some countermeasures should be necessary especially for these patients.

In endometriosis, M2 macrophages (MΦ) are dominant and promote the development of endometriosis lesions. However, the factor(s) which induces M2 MΦ are unknown. In the present study, we focused on interleukin (IL)-33, known as an alarmin and investigated its expression and its role in endometriosis, especially from the point of the relevance with MΦ. The expression of IL-33 in endometriosis lesions was examined by immunohistochemistry. The cystic fluid of ovarian cysts/tumors was obtained and used to measure IL-33 concentration. Endometriotic stromal cells (ESC) and MΦ derived from patients were used for in vitro experiments. IL-33 was detected in the epithelium and stromal cells of endometriotic lesions. The mean IL-33 concentration in the cystic fluid of endometriomas was significantly higher than that in non-endometriomas (2.2 ng/ml vs. 0.02 ng/ml, P

Study Objective To evaluate a new magnetic resonance imaging (MRI) grading system for preoperative differentiation between benign and variant-type uterine leiomyomas including smooth muscle tumors of uncertain malignant potential (STUMPs). Design Retrospective analysis (Canadian Task Force classification III). Setting Teaching hospital (Teine Keijinkai Hospital). Patients Three-hundred thirteen patient medical records were retrospectively reviewed if treated for uterine myomas and diagnosed with variant type leiomyomas or STUMPs (n = 27) or benign, typical leiomyomas (n = 286) and treated between January 2012 and December 2014. Intervention Uterine myoma classifications using MRI findings according to a 5-grade system (grades I–V) based on 3 elements. Measurements and Main Results Uterine myoma MRI classifications were based on 3 elements: T2-weighted imaging (high or low), diffusion-weighted imaging (high or low), and apparent diffusion coefficient values (high or low; apparent diffusion coefficient Conclusion This novel MRI grading system for uterine myomas may be beneficial in differentiating benign leiomyomas from STUMPs or variant type leiomyomas and could be a future effective presurgical assessment tool.

Phenotypic divergence is often unrelated to genotypic divergence. An extreme example is rapid phenotypic differentiation despite genetic similarity. Another extreme is morphological stasis despite substantial genetic divergence. These opposite patterns have been viewed as reflecting opposite properties of the lineages. In this study, phenotypic radiation accompanied by both rapid divergence and long-term conservatism is documented in the inferred molecular phylogeny of the micro land snails Cavernacmella (Assimineidae) on the Ogasawara Islands. The populations of Cavernacmella on the Sekimon limestone outcrop of Hahajima Island showed marked divergence in shell morphology. Within this area, one lineage diversified into types with elongated turret shells, conical shells and flat disc-like shells without substantial genetic differentiation. Additionally, a co-occurring species with these types developed a much larger shell size. Moreover, a lineage adapted to live inside caves in this area. In contrast, populations in the other areas exhibited no morphological differences despite high genetic divergence among populations. Accordingly, the phenotypic evolution of Cavernacmella in Ogasawara is characterized by a pattern of long-term stasis and periodic bursts of change. This pattern suggests that even lineages with phenotypic conservatism could shift to an alternative state allowing rapid phenotypic divergence.

Aim Predation is generally viewed as a factor that limits the distribution of animal prey species. However, in certain instances, such as seed dispersal, predation may enhance the dispersal capability of prey species. In a prior study, we found that land snails are preyed upon by the Japanese white-eye (Zosterops japonicus) and the brown-eared bulbul (Hypsipetes amaurotis) in the Ogasawara Islands. In this paper we provide experimental and field evidence indicating that land snails could potentially be dispersed through bird predation. Location Hahajima Island of the Ogasawara Islands in the western Pacific. Methods Experimentation was first performed to test whether the land snail Tornatellides boeningi could remain alive after being swallowed and passed through the bird digestive system. Next, in order to investigate the potential role of internal bird transport and dispersal of this snail, we investigated the relationship between the distribution of population genetic diversity in the snail and the regional geographical abundance of predatory birds. The population genetic structure of T. boeningi and isolation by distance were inferred with Arlequin. The association between nucleotide diversity in T. boeningi populations and population density of predators was examined using a generalized linear mixed model. We conducted a likelihood ratio test for the full model and for another model that removed the fixed effect. Results Of the 119 snails fed to Japanese white-eyes and 55 snails fed to brown-eared bulbuls, 14.3% and 16.4% of the snails, respectively, passed through the gut alive. Additionally, one snail gave birth to juveniles after emerging from a bird’s gut. Significant heterogeneity among the populations of T. boeningi on Hahajima was indicated using AMOVA; however, there was no evidence of isolation by distance. A positive correlation was found between levels of mitochondrial DNA variation among and within T. boeningi populations and the density of Japanese white-eyes in the wild. Main conclusions Bird predation appears to be a method of dispersal for T. boeningi, and our results suggest that bird-mediated dispersal plays a role in land snail population structure.