CRISPR screening in human trophoblast stem cells reveals both shared and distinct aspects of human and mouse placental development.

The placenta serves as the interface between the mother and fetus, facilitating the exchange of gases and nutrients between their separate blood circulation systems. Trophoblasts in the placenta play a central role in this process. Our current understanding of mammalian trophoblast development relies largely on mouse models. However, given the diversification of mammalian placentas, findings from the mouse placenta cannot be readily extrapolated to other mammalian species, including humans. To fill this knowledge gap, we performed CRISPR knockout screening in human trophoblast stem cells (hTSCs). We targeted genes essential for mouse placental development and identified more than 100 genes as critical regulators in both human hTSCs and mouse placentas. Among them, we further characterized in detail two transcription factors, DLX3 and GCM1, and revealed their essential roles in hTSC differentiation. Moreover, a gene function-based comparison between human and mouse trophoblast subtypes suggests that their relationship may differ significantly from previous assumptions based on tissue localization or cellular function. Notably, our data reveal that hTSCs may not be analogous to mouse TSCs or the extraembryonic ectoderm (ExE) in which in vivo TSCs reside. Instead, hTSCs may be analogous to progenitor cells in the mouse ectoplacental cone and chorion. This finding is consistent with the absence of ExE-like structures during human placental development. Our data not only deepen our understanding of human trophoblast development but also facilitate cross-species comparison of mammalian placentas.

Controlling primary chain dispersity in network polymers: elucidating the effect of dispersity on degradation.

Although dispersity has been demonstrated to be instrumental in determining many polymer properties, current synthetic strategies predominantly focus on tailoring the dispersity of linear polymers. In contrast, controlling the primary chain dispersity in network polymers is much more challenging, in part due to the complex nature of the reactions, which has limited the exploration of properties and applications. Here, a one-step method to prepare networks with precisely tuned primary chain dispersity is presented. By using an acid-switchable chain transfer agent and a degradable crosslinker in PET-RAFT polymerization, the in situ crosslinking of the propagating polymer chains was achieved in a quantitative manner. The incorporation of a degradable crosslinker, not only enables the accurate quantification of the various primary chain dispersities, post-synthesis, but also allows the investigation and comparison of their respective degradation profiles. Notably, the highest dispersity networks resulted in a 40% increase in degradation time when compared to their lower dispersity analogues, demonstrating that primary chain dispersity has a substantial impact on the network degradation rate. Our experimental findings were further supported by simulations, which emphasized the importance of higher molecular weight polymer chains, found within the high dispersity materials, in extending the lifetime of the network. This methodology presents a new and promising avenue to precisely tune primary chain dispersity within networks and demonstrates that polymer dispersity is an important parameter to consider when designing degradable materials.

Precautions during Direct Oral Anticoagulant Introduction in Gynecologic Malignancies: A Single-Center Retrospective Cohort Study.

The risk factors for venous thromboembolism (VTE) recurrence/exacerbation or a change from a direct oral anticoagulant (DOAC) to another anticoagulant in patients with gynecologic cancer using DOACs have not been thoroughly elucidated. Here, we aimed to investigate the risk factors for a composite primary outcome, including VTE recurrence/exacerbation, or a change from a DOAC to another anticoagulant, in this population. A total of 63 patients were analyzed. Risk factors for a primary outcome within 2 years after DOAC initiation were investigated using multiple logistic regression analysis. Among the 63 patients, 10 developed a primary outcome. Clear cell carcinoma of the ovary (adjusted odds ratio (aOR), 18.9; 95% confidence interval (CI), 2.25-350.74), pulmonary embolism (PE) or proximal deep vein thrombosis without PE (aOR, 55.6; 95% CI, 3.29-11,774.66), and D-dimer levels in the third tertile (≥7.6 µg/dL) when VTE was first diagnosed (aOR, 6.37; 95% CI, 1.17-66.61) were associated with increased odds of a primary outcome in patients with gynecologic cancer using DOACs. Patients with one or more risk factors for a primary outcome require careful follow-up after DOAC initiation for the early recognition of treatment failure.

Two cases of CRPC with BRCA mutation treated by olaparib after favorable response to cisplatin.

Introduction: Several prostate cancers carry homologous recombination repair mutations that respond to olaparib. Because of the mechanism, the efficacy of platinum-based therapy can be used to predict the efficacy of poly(adenosine diphosphate-ribose) polymerase inhibitors such as olaparib. Case presentation: We experienced two neuroendocrine prostate cancer patients who achieved a response duration of more than 1 year with platinum-based therapy. Case 1 had a BRCA2 mutation in the germline and case 2 had a BRCA2 mutation in a somatic chromosome only. Both patients responded well to olaparib. Conclusion: Cisplatin and olaparib may overlap in response due to their medicinal action. It may be useful to consider genetic testing in some CRPC patients who have responded to cisplatin.

Snapping Knee Syndrome of the Sartorius Accompanying Osteoarthritis Cured by Osteophyte Removal During Total Knee Arthroplasty.

Snapping knee syndrome on the medial side is rare. Here, we report the case of a patient with snapping knee syndrome of the sartorius with knee osteoarthritis. A large osteophyte at the posteromedial femoral condyle impinged on the sartorius myotendinous junction, causing painless snapping. The patient was successfully treated with osteophyte removal and total knee arthroplasty while preserving the tendon. Hence, tendon release or resection to treat snapping syndrome is not always necessary if the underlying cause can be eliminated. Furthermore, we found that while tendon tension is important for the occurrence of snapping syndrome, the impingement site determines the occurrence of snapping pain.

A Retrospective Analysis of Clinical Biomarkers for Olaparib Maintenance Therapy in Patients with Recurrent Ovarian Cancer.

Poly(ADP-ribose) polymerase (PARP) inhibitors theoretically promote synthetic lethality in cancer cells with homologous recombination deficiency (HRD). However, clinical evidence indicates that PARP inhibitors are also effective for treating HRD-negative ovarian cancer. The PARP inhibitor olaparib became available in Japan as a maintenance therapy for platinum-sensitive recurrent ovarian cancer regardless of homologous recombination status in April 2018. The purpose of this study was to identify potential clinical biomarkers for olaparib sensitivity in patients with recurrent ovarian cancer. Clinical information about the patients with recurrent ovarian cancer treated with olaparib maintenance therapy (OMT) was retrospectively collected. OMT duration was used as an indicator for olaparib sensitivity. The relationship between OMT duration and clinical parameters was statistically analyzed. We found a positive correlation between OMT duration and progression-free survival (PFS) or treatment free interval (TFI). In some cases, OMT duration exceeded PFS before olaparib introduction. We also found that more than half of the patients with measurable target lesions at the time of OMT introduction showed partial or complete response to OMT. These results validated the effectiveness of OMT and identified PFS and TFI as potential clinical markers for olaparib sensitivity in the patients with recurrent ovarian cancer.

Tourism infrastructure and the environment: how does environmental regulation affect welfare, tourism industry, and domestic wage inequality?

This study presents a general equilibrium model of a small open developing economy with pollution generated by the tourism industry. The national government issues emission permits and constructs tourism infrastructure for the tourism sector. We examine the effects of a stricter environmental regulation on welfare, production, and income distribution. If the elasticity of substitution in the tourism sector is sufficiently low, a stricter environmental regulation paradoxically expands the tourism sector and narrows domestic wage inequality, even under constant tourism terms of trade. In this model, in addition to the two traditional channels, there is a new channel through which a stricter environmental regulation affects the tourism terms of trade and domestic welfare. The new channel, which arises from the difference between the marginal value product of tourism infrastructure and its price, improves the tourism terms of trade and domestic welfare if (1) the marginal value product of tourism infrastructure is greater than its price, (2) the output of tourism infrastructure is increased by a stricter environmental regulation, and (3) the excess supply of a tourism service decreases with a stricter environmental regulation.

Tuning Ligand Concentration in Cu(0)-RDRP: A Simple Approach to Control Polymer Dispersity.

Cu(0)-reversible deactivation radical polymerization (RDRP) is a versatile polymerization tool, providing rapid access to well-defined polymers while utilizing mild reaction conditions and low catalyst loadings. However, thus far, this method has not been applied to tailor dispersity, a key parameter that determines the physical properties and applications of polymeric materials. Here, we report a simple to perform method, whereby Cu(0)-RDRP can systematically control polymer dispersity (D = 1.07-1.72), while maintaining monomodal molecular weight distributions. By varying the ligand concentration, we could effectively regulate the rates of initiation and deactivation, resulting in polymers of various dispersities. Importantly, both low and high dispersity PMA possess high end-group fidelity, as evidenced by MALDI-ToF-MS, allowing for a range of block copolymers to be prepared with different dispersity configurations. The scope of our method can also be extended to include inexpensive ligands (i.e., PMDETA), which also facilitated the polymerization of lower propagation rate constant monomers (i.e., styrene) and the in situ synthesis of block copolymers. This work significantly expands the toolbox of RDRP methods for tailoring dispersity in polymeric materials.

Standing stock and mass balance of marine litter in the Seto Inland Sea, Japan.

The basin of Seto Inland Sea has a population of 31 million people. The standing stock and mass balance of marine litter in this area was estimated using rapid assessment for beach litter, questionnaire surveys on removed amounts of marine litter, and existing data. The mass balance of marine litter was explained by using a single box model, assuming complete mixing and uniform density. If the standing stock of drifting and beach litter combined was 3400 tons, the inflow of litter from rivers was 3000 tons/year, generation of litter at sea was 1200 tons/year, and inflow from the open sea was 300 tons/year. The amount of marine litter removed from the beach and sea surface was 1400 tons/year, outflow to the open sea was 2400 tons/year, and deposition on the sea bottom was 700 tons/year.

Estimating spatial variation in the effects of climate change on the net primary production of Japanese cedar plantations based on modeled carbon dynamics.

Spatiotemporal prediction of the response of planted forests to a changing climate is increasingly important for the sustainable management of forest ecosystems. In this study, we present a methodology for estimating spatially varying productivity in a planted forest and changes in productivity with a changing climate in Japan, with a focus on Japanese cedar (Cryptomeria japonica D. Don) as a representative tree species of this region. The process-based model Biome-BGC was parameterized using a plant trait database for Japanese cedar and a Bayesian optimization scheme. To compare productivity under historical (1996-2000) and future (2096-2100) climatic conditions, the climate scenarios of two representative concentration pathways (i.e., RCP2.6 and RCP8.5) were used in five global climate models (GCMs) with approximately 1-km resolution. The seasonality of modeled fluxes, namely gross primary production, ecosystem respiration, net ecosystem exchange, and soil respiration, improved after two steps of parameterization. The estimated net primary production (NPP) of stands aged 36-40 years under the historical climatic conditions of the five GCMs was 0.77 ± 0.10 kgC m-2 year-1 (mean ± standard deviation), in accordance with the geographical distribution of forest NPP estimated in previous studies. Under the RCP2.6 and RCP8.5 scenarios, the mean NPP of the five GCMs increased by 0.04 ± 0.07 and 0.14 ± 0.11 kgC m-2 year-1, respectively. The increases in annual NPP were small in the southwestern region because of the decreases in summer NPP and the small increases in winter NPP under the RCP2.6 and RCP8.5 scenarios, respectively. Under the RCP2.6 scenario, Japanese cedar was at risk in the southwestern region, in accordance with previous studies, and monitoring and silvicultural practices should be modified accordingly.

Clinical impact of prophylactic clip closure of mucosal defects after colorectal endoscopic submucosal dissection.

BACKGROUND AND STUDY AIMS: Endoscopic submucosal dissection (ESD) is useful for en bloc resection of superficial colorectal neoplasms to ensure accurate histologic diagnoses. However, colorectal ESD is associated with a high frequency of adverse events (AEs). We aimed to investigate the effectiveness of prophylactic clip closure (PCC) of mucosal defects for AEs after colorectal ESD. PATIENTS AND METHODS: This study included 197 patients with 211 lesions who underwent colorectal ESD between June 2010 and August 2016. Patients who had delayed perforation, delayed bleeding, abdominal pain, or fever were defined as AEs after colorectal ESD. Complete PCC was defined as completely sutured mucosal defect using endoclips following colorectal ESD, whereas incomplete PCC was defined as the mucosal defects that did not enable PCC or were partially sutured. Clinical records were retrospectively reviewed and clinical outcomes evaluated. RESULTS: AEs occurred in 29 lesions (13.7 %), including 12 with delayed bleeding, 12 with fever, 2 with abdominal pain, 2 with fever and abdominal pain, and 1 with delayed bleeding and fever. Delayed perforation was not observed in any patient. The frequency of AEs was significantly lower in the group with complete PCC than in the group with incomplete PCC (7.3 % [9/123] vs. 22.7 % [20/88]; P  < 0.001). Multivariate analysis revealed that AEs after colorectal ESD were significantly associated with tumor size and submucosal fibrosis. Subgroup analysis among the resected specimen size of < 40 mm revealed that there was no significant difference in AEs between the 2 groups (5.6 % [6/107] vs. 17.8 % [8/45]; P  = 0.069). However, the frequency of fever with complete PCC was significantly lower than that with incomplete PCC (2.8 % [3/107] vs. 13.3 % [6/45]; P  = 0.020). CONCLUSIONS: Tumor size and submucosal fibrosis were independent risk factors for AEs after colorectal ESD. PCC may be effective in minimizing AEs after colorectal ESD, especially the frequency of fever.

Continuous use of low-dose warfarin for gastric endoscopic submucosal dissection: a prospective study.

Background and study aims Patients who receive warfarin usually require heparin bridge therapy (HBT) to prevent thromboembolic events during endoscopic submucosal dissection (ESD); however, clinical evidence demonstrating the safety and efficacy of HBT during gastric ESD is limited. Conversely, warfarin can be continuously used as a substitute for HBT to endoscopic procedures which have a low risk of bleeding. This study aimed to clarify the safety and efficacy of continuous low-dose warfarin (LDW) for gastric ESD. Patients and methods This was a prospective observational study at a single institution. A total of 22 patients who received warfarin between December 2014 and January 2016 were enrolled. The patients were treated with gastric ESD with a low dose of warfarin ( ≤ 4 mg) at approximately 1.6 - 2.6 of the international normalized ratio (INR) levels. Furthermore, we analyzed a total of 23 patients with HBT who underwent gastric ESD between January 2011 and November 2014. Results The average of warfarin dose and the INR level on the day of gastric ESD in the continuous LDW group were 2.3 mg/day (range 0.5 - 4.0) and 1.87 (range 1.41 - 2.75), respectively. Two of the 22 patients (9.1 %) in the continuous LDW group and 5 of the 23 patients (21.7 %) in the HBT group had postoperative bleeding after gastric ESD. Although the postoperative bleeding rate in the continuous LDW group was lower than that in the HBT group, no significant difference was observed between the 2 groups (P = 0.414). Conclusions Gastric ESD with continuous LDW as a substitute for HBT was feasible and may be acceptable.

Endoscopic submucosal dissection for small submucosal tumors of the rectum compared with endoscopic submucosal resection with a ligation device.

AIM: To evaluate the efficacy and safety of endoscopic submucosal dissection (ESD) for small rectal submucosal tumors (SMTs). METHODS: Between August 2008 and March 2016, 39 patients were treated with endoscopic submucosal resection with a ligation device (ESMR-L) (n = 21) or ESD (n = 18) for small rectal SMTs in this study. Twenty-five lesions were confirmed by histological evaluation of endoscopic biopsy prior to the procedure, and 14 lesions were not evaluated by endoscopic biopsy. The results for the ESMR-L group and the ESD group were retrospectively compared, including baseline characteristics and therapeutic outcomes. RESULTS: The rate of en bloc resection was 100% in both groups. Although the rate of complete endoscopic resection was higher in the ESD group than in the ESMR-L group (100% vs 95.2%), there were no significant differences between the two groups (P = 0.462). In one patient in the ESMR-L group with a previously biopsied tumor, histological complete resection with a vertical margin involvement of carcinoid tumor could not be achieved, whereas there was no incomplete resection in the ESD group. The mean length of the procedure was significantly greater in the ESD group than in the ESMR-L group (14.7 ± 6.4 min vs 5.4 ± 1.7 min, P < 0.05). The mean period of the hospitalization was also significantly longer in the ESD group than in the ESMR-L group (3.7 ± 0.9 d vs 2.8 ± 1.5 d, P < 0.05). Postoperative bleeding was occurred in one patient in the ESMR-L group. CONCLUSION: Both ESMR-L and ESD were effective for treatment of small rectal SMTs. ESMR-L was simpler to perform than ESD and took less time.

Characteristics of proteinaceous additives in stabilizing enzymes during freeze-thawing and -drying.

Protein-stabilizing characteristics of sixteen proteins during freeze-thawing and freeze-drying were investigated. Five enzymes, each with different instabilities against freezing and dehydration, were employed as the protein to be stabilized. Proteinaceous additives generally resulted in greater enzyme stabilization during freeze-thawing than sugars while the degree of stabilization for basic lysozyme and protamine were inferior to that of neutral and acidic proteins. Freeze-drying-induced inactivation of enzyme was also reduced by the presence of a proteinaceous additive, the extent of which was lower than that for a sugar. In both freeze thawing and freeze drying, the enzymes stabilization by the proteinaceous additive increased with increasing additive concentration. The enhancement of enzyme inactivation caused by pH change was also reduced in the presence of proteinaceous additives. The combined use of a sugar such as sucrose and dextran tended to increase the stabilizing effect of the proteinaceous additive.

Ligation-assisted endoscopic submucosal resection with circumferential mucosal incision for duodenal carcinoid tumor.

Here we present the case of a 64-year-old female with a duodenal carcinoid tumor treated by ligation-assisted endoscopic submucosal resection (ESMR-L) with circumferential mucosal incision (CMI). Band ligation was effective in resecting the duodenal carcinoid tumor after CMI, with an uneventful post-procedural course. Histopathological examination showed clear tumor margins at deeper tissue levels. Thus, in the present case, ESMR-L with CMI was useful for the treatment of duodenal carcinoid tumor.

Endoscopic submucosal dissection for early gastric cancer without interruption of warfarin and aspirin.

Many guidelines for the management of antithrombotic therapy in endoscopic procedures state that warfarin should be replaced by heparin in high risk endoscopic procedures. However, heparin bridging therapy is costly, requires a long hospital stay, and is indicated as a risk factor for bleeding after endoscopic submucosal dissection (ESD). It is not yet clear whether it is better to perform gastric ESD on continuous warfarin therapy or heparin bridging therapy. We report the case of a 65-year-old Japanese man who had been diagnosed with early gastric cancer. He had a past medical history of metallic valve replacement for mitral valve regurgitation, coronary artery disease with bare metal stent, and coronary artery bypass graft. Warfarin and low dose aspirin had been used to prevent thromboembolic events in the metallic mitral valve and coronary artery stent. We performed gastric ESD safely on continuous warfarin and low dose aspirin without any complications.