Self-propelled object that generates a boundary with amphiphiles at an air/aqueous interface

A benzoic acid (BA) disk was investigated as a novel self-propelled object whose driving force was the difference in surface tension. 4-Stearoyl amidobenzoic acid (SABA) was synthesized as an amphiphile to control the nature of motion based on intermolecular interactions between BA and SABA. The BA disk exhibited characteristic motion depending on the surface density of the SABA on the aqueous phase, that is, reciprocating motion as a one-dimensional motion and restricted and unrestricted motion as a two-dimensional motion. The trajectory of the reciprocating motion was determined by the initial direction of motion, and the boundary between an aqueous surface and the BA-SABA condensed molecular layer was used as the field's boundary. The presented results indicate that the characteristic nature of motion can be designed at the molecular level based on the intermolecular interactions between an energy-source molecule and an amphiphile.

Can self-propelled objects escape from compression stimulation?

We studied circular papers impregnated with camphor (CPs) and CPs with magnets (MCPs) as self-propelled objects floating on water under the compression of the water surface as an inanimate system for evacuation in an emergency. Two water chambers-Cin and Cout-were connected via a plastic gate, and eight CPs or eight MCPs were placed on Cin. We monitored the movement of the CPs or MCPs from Cin to Cout when the gate was opened and the area of Cin (Ain) was decreased using a barrier. When Ain was large, CPs moved stochastically from Cin to Cout while exhibiting random motion. The escape probability from Cin to Cout (P) at time t = 20 s increased with a decrease in Ain, and the rate of increase in P increased depending on the width of the gate (Wg). By contrast, clustering was observed for MCPs. Consequently, P of MCPs was lower than that of CPs. The difference in the surface tension between Cin and Cout (Δγ) increased with a decrease in Ain. P is discussed in relation to Δγ as the driving force for emergencies and the repulsive forces between CPs or attractive forces between MCPs. These results suggest that the repulsive force enhances the self-propulsion of objects towards the gate, that is, as a result, higher values of P are obtained.

Using strain to uncover the interplay between two- and three-dimensional charge density waves in high-temperature superconducting YBa2Cu3Oy

Uniaxial pressure provides an efficient approach to control charge density waves in YBa2Cu3Oy. It can enhance the correlation volume of ubiquitous short-range two-dimensional charge-density-wave correlations, and induces a long-range three-dimensional charge density wave, otherwise only accessible at large magnetic fields. Here, we use x-ray diffraction to study the strain dependence of these charge density waves and uncover direct evidence for a form of competition between them. We show that this interplay is qualitatively described by including strain effects in a nonlinear sigma model of competing superconducting and charge-density-wave orders. Our analysis suggests that strain stabilizes the 3D charge density wave in the regions between disorder-pinned domains of 2D charge density waves, and that the two orders compete at the boundaries of these domains. No signatures of discommensurations nor of pair density waves are observed. From a broader perspective, our results underscore the potential of strain tuning as a powerful tool for probing competing orders in quantum materials.

Effects of the Molecular Structure of Malodor Substances and Their Masking on 1,2-Dioleoyl-sn-glycero-3-phosphocholine Molecular Layers

Certain odors have been shown not only to cause health problems and stress but also to affect skin barrier function. Therefore, it is important to understand olfactory masking to develop effective fragrances to mask malodors. However, olfaction and olfactory masking mechanisms are not yet fully understood. To understand the mechanism of the masking effect that has been studied, the responses of several target substance (TS) molecules-1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) mixed molecular layers to odorant (OD) molecules were examined as a simple experimental model of epithelial cellular membranes injured by TS molecules. Here, we examined trans-2-nonenal, 1-nonanal, trans-2-decenal, and 1-decanal as TS molecules to clarify the effects of double bonds and hydrocarbon chain lengths on the phospholipid molecular layer. In addition, benzaldehyde and cyclohexanecarboxaldehyde were utilized as OD molecules to clarify the masking effect of the aromatic ring. Surface pressure (Π)-area (A) isotherms were measured to clarify the adsorption or desorption of TS and OD molecules on the DOPC molecular layer. In addition, Fourier transform infrared spectroscopy was performed to clarify the interactions among DOPC, TS, and OD molecules. We found that TS molecules with and without double bonds had different effects on the DOPC molecular layer and that molecules with shorter chain lengths had greater effects on the DOPC molecular layer. Furthermore, OD molecules with aromatic rings counteracted the effects of the TS molecules. On the basis of this research, not only a detailed mechanism by which odor molecules affect lipid membranes without mediating olfactory receptors is elucidated but also more effective OD molecules with masking effects are proposed.

Comparison of Early Postoperative Diffusion Weighted Magnetic Resonance Imaging Findings After Resection of Gliomas and Meningiomas

OBJECTIVE

Glioma and meningioma require vastly different surgical approaches, even if only involving a simple craniotomy procedure. Diffusion weighted imaging (DWI) is useful for the postoperative evaluation of ischemic damage. The present study evaluated the expected but unproven differences in DWI findings.

METHODS

A total of 41 patients with meningiomas and 63 with gliomas met the inclusion criteria for adult cases with superficial lesions treated through simple supratentorial craniotomy. Postoperative DWI findings of DWI-positive rate, DWI-positive area type, and relationship with neurological deficits were evaluated.

RESULTS

The DWI-positive rate (P = 0.01) and the proportion of rim-type lesions (P < 0.01) were significantly more common in gliomas. Patients with meningiomas and DWI-positive areas presented with higher rates of new neurological deficits (P < 0.01), and patients with meningiomas on the left side were more likely to develop new neurological deficits (P = 0.02). Patients with gliomas tended to develop new deficits with larger DWI-positive area volumes (P = 0.04).

CONCLUSIONS

Postoperative early DWI-positive rate and rim-type lesions are more common after glioma resection than meningioma resection. Larger volumes of DWI-positive areas may be associated with postoperative neurological symptoms in gliomas. DWI-positive finding is less common after meningioma than glioma resection but more likely to be associated with new neurological symptoms. These differences are important for adequate postoperative DWI evaluation of common supratentorial brain tumors.

Self-propelled motion controlled by ionic liquids

We studied the self-propulsion of a camphor disk floating on a water surface using two types of ionic liquids (hexylammonium-trifluoroacetate (HHexam-TFA) and hexylethylenediaminium-trifluoroacetate (HHexen-TFA)). Bifurcation between continuous, oscillatory, and no motion was observed depending on the concentration of the ionic liquid. The bifurcation concentration between oscillatory and no motion for HHexam-TFA was lower than that for HHexen-TFA. The different bifurcation concentrations are discussed in relation to the surface tension and Fourier transform infrared spectra of the mixtures of camphor and ionic liquids. These results suggest that the interaction between the ionic liquid molecules at the air/water interface is weakened by the addition of camphor molecules and the features of self-propulsion vary due to the change in the driving force.

Experiences and care needs of post-discharge patients who underwent cardiac surgery: A qualitative study

AIM

This study clarifies the physical, psychological, and social forms of distress in, and care needs of, cardiac surgery patients, including optimal times for supporting them in their post-hospital discharge daily lives.

METHODS

Semi-structured qualitative interviews were conducted. Participants included 12 adults (11 male and one female, mean age = 66.5 years) who had undergone cardiac surgery, experienced intensive care, and received outpatient care at the first post-discharge visit (around 2 ~ 3 weeks after discharge), around 3 months after discharge, and between 3 months and 1 year after discharge. Verbatim transcripts were analyzed based on similarities and differences for codes based on assessment items, and subcategories and categories were generated.

RESULTS

After surgery, patients experienced physical, psychological, and social distress. First, they experienced physical pain shortly after discharge. Moreover, as they recovered at home, a gap between their sense of their recovery and the perceptions of those around them about their recovery often persisted, which led to psychological and social distress. Patients gained a sense of safety through "assurance of physical recovery" and security through "shared subjective distress."

CONCLUSIONS

Post-cardiac surgery patients seek reassurance and safety by sharing experiences owing to daily life distress. Our findings could help provide better support to meet the care needs of such patients.

Phospholipid Molecular Layer that Enhances Distinction of Odors Based on Artificial Sniffing

We propose a novel odor-sensing system based on the dynamic response of phospholipid molecular layers for artificial olfaction. Organisms obtain information about their surroundings based on multidimensional information obtained from sniffing, i.e., periodic perturbations. Semiconductor- and receptor-based odor sensors have been developed previously. However, these sensors predominantly identify odors based on one-dimensional information, which limits the type of odor molecule they can identify. Therefore, the development of odor sensors that mimic the olfactory systems of living organisms is useful to overcome this limitation. In this study, we developed a novel odor-sensing system based on the dynamics of phospholipids that responds delicately to chemical substances at room temperature using multidimensional information obtained from periodic perturbations. Odor molecules are periodically supplied to the phospholipid molecular layer as an input sample. The waveform of the surface tension of the phospholipid molecular layer changes depending on the odor molecules and serves as an output. Such characteristic responses originating from the dynamics of odor molecules on the phospholipid molecular layer can be reproduced numerically. The phospholipid molecular layer amplified the information originating from the odor molecule, and the mechanism was evaluated by using surface pressure-area isotherms. This paper offers a platform for an interface-chemistry-based artificial sniffing system as an active sensor and a novel olfactory mechanism via physicochemical responses of the receptor-independent membranes of the organism.

Oscillatory Motion of an Organic Droplet Reflecting a Reaction Scheme

An organic droplet containing thymol acetate (TA) floating on a sodium dodecyl sulfate aqueous phase was examined to develop a novel self-propelled object based on reaction kinetics. Two types of oscillatory motion, without back-and-forth motion (Osc I) and with back-and-forth motion (Osc II), were observed by varying the pH of the aqueous phase. The oscillation frequency reached its maximum at pH 9.6, coinciding with the occurrence of Osc II. The kinetics of the hydrolysis of TA as a reactant and the acid-base equilibrium between thymol (TOH) and the thymolate ion (TO-) as products were evaluated experimentally. The driving force of motion was discussed on the basis of the interfacial tension. The pH dependence of the oscillation frequency and the selection of Osc I or II were attributed to the equilibrium between the TOH and TO-. These results highlight the possibility of designing self-propulsion systems by considering reaction kinetics and chemical properties.

Recursively positive and negative chemotaxis coupling with reaction kinetics in self-organized inanimate motion

Reconstructing recursive chemotaxis in inanimate self-propelled objects is inevitable in the development of recursively and autonomously artificial mass transport systems. However, the fabrication of inanimately recursive chemotaxis has been extremely challenging because of the difficulty in introducing competitive positive and negative feedback into an inanimate self-propelled object. Herein, a coumarin derivative (coumarin, 4-methylcoumarin (4-MC), or 6-methylcoumarin (6-MC))-based disk floated on water as a self-propelled object exhibited characteristic features of motion; these features include continuous motion, repetition between positive and negative chemotaxis to the Na₃PO₄ powder as a base stimulus, and oscillatory motion above the Na₃PO₄ powder depending on the Na₃PO₄ density of the powder and the functional group of coumarin derivatives. The mechanism of the characteristic features of motion to the base stimulus is discussed in relation to the surface tension of the coumarin derivatives as the driving force of motion and the reaction rate of the hydrolysis between coumarin derivatives and OH^- obtained from Na₃PO₄. This study suggests a novel avenue for developing a recursive chemotactic system coupled with reaction kinetics in self-organized motion.

Height-dependent oscillatory motion of a plastic cup with a camphor disk floated on water

We have developed a self-propelled object, which is composed of a plastic cup and a camphor disk, on water to reflect its three-dimensional shape in the nature of motion. The self-propelled object, of which the driving force of motion is the difference in the surface tension, exhibited oscillatory motion between motion and rest. The period and the maximum speed of oscillatory motion increased and decreased depending on the height of the cup, h, respectively. Two types of diffusion coefficients were estimated based on the diffusion of camphor molecules which were indirectly visualized using 7-hydroxycoumarin. The experimental result on the period of oscillatory motion depending on h could be reproduced by the numerical calculation based on the diffusion of camphor molecules around the object and the diffusion coefficients which were experimentally estimated. The experimental results suggest that characteristic features of motion can be created based on the three-dimensional shape of the object.

Epigenetic upregulation of Schlafen11 renders WNT- and SHH-activated medulloblastomas sensitive to cisplatin

BACKGROUND

Intensive chemotherapeutic regimens with craniospinal irradiation have greatly improved survival in medulloblastoma patients. However, survival markedly differs among molecular subgroups and their biomarkers are unknown. Through unbiased screening, we found Schlafen family member 11 (SLFN11), which is known to improve response to DNA damaging agents in various cancers, to be one of the top prognostic markers in medulloblastomas. Hence, we explored the expression and functions of SLFN11 in medulloblastoma.

METHODS

SLFN11 expression for each subgroup was assessed by immunohistochemistry in 98 medulloblastoma patient samples and by analyzing transcriptomic databases. We genetically or epigenetically modulated SLFN11 expression in medulloblastoma cell lines and determined cytotoxic response to the DNA damaging agents cisplatin and topoisomerase I inhibitor SN-38 in vitro and in vivo.

RESULTS

High SLFN11 expressing cases exhibited significantly longer survival than low expressing cases. SLFN11 was highly expressed in the WNT-activated subgroup and in a proportion of the SHH-activated subgroup. While WNT activation was not a direct cause of the high expression of SLFN11, a specific hypomethylation locus on the SLFN11 promoter was significantly correlated with high SLFN11 expression. Overexpression or deletion of SLFN11 made medulloblastoma cells sensitive and resistant to cisplatin and SN-38, respectively. Pharmacological upregulation of SLFN11 by the brain-penetrant histone deacetylase-inhibitor RG2833 markedly increased sensitivity to cisplatin and SN-38 in SLFN11-negative medulloblastoma cells. Intracranial xenograft studies also showed marked sensitivity to cisplatin by SLFN11-overexpression in medulloblastoma cells.

CONCLUSIONS

High SLFN11 expression is one factor which renders favorable outcomes in WNT-activated and a subset of SHH-activated medulloblastoma possibly through enhancing response to cisplatin.

Characteristic growth of chemical gardens from mixtures of two salts

Chemical gardens formed from two metal salts (MCl₂ or MSO₄) have been investigated to understand the effects of mixing on the growth of precipitate tubes. The growth of tubes can be classified into three types, i.e., collaborative, inhibited, and individual growth, depending on the combination of the two metal salts. Characteristic features of tube growth are discussed in relation to the flow near the tip of the tube controlled by osmotic pressure and the solubility product, K_sp, for M(OH)₂. The present study can be interpreted as an inanimate model system of symbiosis among different species, such as mixed cropping systems and survival among different kinds of microbial cells.

Sequentially Selective Coalescence of Binary Self-Propelled Droplets upon Collective Motion

Subsequent synthesis and detection using droplets as microreactors have shown promise in the development of novel materials and drugs because microreactors enable small-scale synthesis and detection of covalent/non-covalent intermolecular interactions. Self-organization exhibited by autonomous droplets under non-equilibrium conditions is beneficial for manipulating the sequentiality and selectivity of droplet coalescence because expensive equipment or elaborate techniques are not required with the autonomy of droplets. However, to our knowledge, selective coalescence caused by the collective motion of self-propelled droplets has not been demonstrated in inanimate systems. Here, we report sequentially selective coalescence based on the dynamic collective pattern of self-propelled droplets composed of ethyl salicylate (ES) or butyl salicylate (BS). When ES and BS droplets were placed on an aqueous sodium dodecyl sulfate (SDS) solution, the collective motion of droplets resulted in three stages of selective coalescence on the time development. Initially, coalescence was observed only between different types of self-propelled droplets. Subsequently, the formed droplets selectively coalesced with ES droplets. Finally, mature droplets merged with BS droplets. The sequentially selective coalescence was discussed from the dynamic pattern formation of swarming droplets and the collapse of the SDS monolayer at the o/w interface caused by the difference in Laplace pressure and the interfacial instability at the contact point between droplets. Thus, this study formulates a strategy of sequentially selective coalescence of droplets via the collective motion of non-identical self-propelled droplets, promoting a new type of powerful and efficient automation technology based on an autonomous inanimate manner of spatiotemporal pattern formation under non-equilibrium conditions for the droplet manipulation.

Emergent surgical evacuation of traumatic intracranial hematoma in patients with preoperative thrombocytopenia: surgical risk and early outcome

BACKGROUND

Surgical evacuation of intracranial hematoma, including epidural, subdural, intracerebral, and intraventricular hematoma, is recommended in patients with traumatic brain injury (TBI) for prevention of cerebral herniation and possible saving of life. However, preoperative coagulopathy is a major concern for emergent surgery on patients with severe TBI.

METHODS

We reviewed 65 consecutive patients with severe TBI who underwent emergency craniotomy for intracranial hematomas.

RESULTS

Univariate analysis showed preoperative pupil abnormality, absence of pupil light reflex, respiratory failure, preoperative thrombocytopenia (< 100 × 10⁹/L), increased activated partial thromboplastin time (> 36 s), low fibrinogen (< 150 mg/dL), platelet transfusion, red cell concentrate transfusion, and presence of brain contusion and traumatic subarachnoid hemorrhage (SAH) on computed tomography were correlated with poor outcome (death or vegetative state). Multivariate analysis revealed that pupil abnormality (p = 0.001; odds ratio [OR] 0.064, 95% confidence interval [CI] 0.012-0.344), preoperative thrombocytopenia (p = 0.016; OR 0.101, 95% CI 0.016-0.656), and traumatic SAH (p = 0.021; OR 0.211, 95% CI 0.057-0.791) were significant factors. Investigation of the 14 patients with preoperative thrombocytopenia found the emergency surgery was successful, with no postoperative bleeding during hospitalization. However, half of the patients died, and almost a quarter remained in the vegetative state mainly associated with severe cerebral edema.

CONCLUSIONS

Emergent craniotomy for patients with severe TBI who have preoperative thrombocytopenia is often successful, but the prognosis is often poor. Emergency medical care teams and neurosurgeons should be aware of this discrepancy between successful surgery and poor prognosis in these patients. Further study may be needed on the cerebral edema regulator function of platelets.

SPDR-4 SLFN11 RENDERS MEDULLOBLASTOMA SENSITIVE TO DNA DAMAGE CHEMOTHERAPIES

Background

Intensive chemotherapeutic regimens with craniospinal irradiation have greatly improved survival in medulloblastoma patients. However, survival markedly differs among molecular subgroups and their biomarkers are unknown. Through unbiased screening, we found Schlafen family member 11 (SLFN11), which is known to improve response to DNA damaging agents in various cancers, to be one of the top prognostic markers in medulloblastomas. Hence, we explored the expression and functions of SLFN11 in medulloblastoma.

Methods

SLFN11 expression for each subgroup was assessed by immunohistochemistry in 98 medulloblastoma patient samples and by analyzing transcriptomic databases. We genetically or epigenetically modulated SLFN11 expression in medulloblastoma cell lines and determined cytotoxic response to the DNA damaging agents cisplatin and topoisomerase I inhibitor SN-38 in vitro and in vivo.

Results

High SLFN11 expressing cases exhibited significantly longer survival than low expressing cases. SLFN11 was highly expressed in the WNT-activated subgroup and in a proportion of the SHH-activated subgroup. While WNT activation was not a direct cause of the high expression of SLFN11, a specific hypomethylation locus on the SLFN11 promoter was significantly correlated with high SLFN11 expression. Overexpression or deletion of SLFN11 made medulloblastoma cells sensitive and resistant to cisplatin and SN-38, respectively. Pharmacological upregulation of SLFN11 by the brain-penetrant histone deacetylase-inhibitor RG2833 markedly increased sensitivity to cisplatin and SN-38 in SLFN11-negative medulloblastoma cells. Intracranial xenograft studies also showed marked sensitivity to cisplatin by SLFN11-overexpression in medulloblastoma cells.

Conclusions

High SLFN11 expression renders favorable outcomes in WNT-activated and a subset of SHH-activated medulloblastoma through enhancing response to cisplatin.

Analysis of clinicopathological features and NAB2-STAT6 fusion variants of meningeal solitary fibrous tumor with ectopic salivary gland components in the cerebellopontine angle

Solitary fibrous tumors (SFTs) are rare mesenchymal tumors that can occur at any location. Since the identification of specific NAB2-STAT6 fusion in SFTs, the fusion gene variants, NAB2 exon 4-STAT6 exon 2/3 and NAB2 exon 5/6/7-STAT6 exon 16/17/18, have been reported to be associated with clinicopathological features, and the latter variant is predominant in meningeal SFTs. SFTs developing in the salivary glands are rare, and more rarely, those involving ectopic salivary glands (ESGs) have been reported in the cerebellopontine angle (CPA); however, their characteristics remain not well understood. In this study, we performed a clinicopathological and molecular analysis of 3 cases of meningeal SFT with ESGs. All cases presented with an extra-axial mass in the CPA, which is a rarer location for intracranial ESGs compared to the sellar region. Histologically, except for the presence of ESGs, there was no significant difference between current cases and ordinary SFTs. The ESGs demonstrated no cellular atypia, and although the spindle tumor cells were immunopositive for STAT6, the ESGs were negative in all cases, supporting that the ESGs are non-neoplastic components. In 1 case, ESGs were found only in the primary tumor and disappeared in recurrence/dissemination. Of note, molecular analysis identified NAB2 exon 4-STAT6 exon 2 in all cases. In conclusion, our results suggest that ESGs particularly in the CPA may be associated with SFTs and that meningeal SFTs with ESGs may be associated with the minor fusion variant of NAB2-STAT6 in the intracranial lesions.

Endoscopic Extended Transsphenoidal Approach for Sellar and Suprasellar Xanthogranuloma: Potential Implications for Surgical Strategies in Adult Craniopharyngioma

OBJECTIVE

Differentiation of suprasellar xanthogranuloma (XG) from adult craniopharyngioma (CP) can be problematic in endoscopic extended transsphenoidal surgery.

METHODS

We reviewed the clinical data, preoperative imaging, intraoperative endoscopic findings, and intraoperative frozen section pathology in newly diagnosed adult CPs (19 patients) and XGs (6 patients).

RESULTS

Intracystic signal intensity was often high on T1-weighted magnetic resonance images in the XGs but low in the CPs (P = 0.015). Capsular intensity was low on T2-weighted imaging in XGs but iso to high in CPs (P < 0.001). Capsular gadolinium enhancement was often seen in CPs and not in XGs (P < 0.001). CPs often had a solid component with contrast enhancement but none in XGs (P < 0.001). Intraoperative endoscopic observations frequently found a whitish solid component in the CPs but yellow to brown fibrous granulomatous lesions in XGs (P < 0.001). The tumor capsule was dark grayish and soft in CPs, whereas it was fibrously hard in XGs (P = 0.002). Yellowish hemosiderin deposits were seen in all XGs (P = 0.003). Intraoperative pathologic diagnosis of CP was all verified whereas no evidence of tumor was found in XGs (P < 0.001). Partial removal was performed in 4 patients with XGs. No recurrence was observed in these patients during the follow-up period (1.5-8 years).

CONCLUSIONS

Careful interpretation of preoperative magnetic resonance imaging, intraoperative endoscopic findings, and intraoperative frozen section diagnosis may be important for the differential diagnosis between XG and CP. In endoscopic-extended transsphenoidal surgery, intentional partial removal can be effective for XG after careful diagnosis.

Therapeutic Drug Monitoring of Golimumab for the Prediction of Long-Term Clinical Remission in Patients with Ulcerative Colitis

BACKGROUND AND AIMS

A considerable number of patients with ulcerative colitis (UC) who initially respond to golimumab (GLM), an anti-TNF-α antibody, gradually lose clinical response. Therapeutic drug monitoring has been proposed to optimize serum anti-TNF-α antibody concentrations before the loss of response; however, little is known about ideal serum GLM concentrations. We aimed to evaluate whether the serum GLM trough levels (TLs) early after the initiation of induction therapy affect the long-term outcomes in UC and to identify the early GLM TLs that should be targeted for better long-term outcomes.

METHODS

Thirty-one patients were prospectively evaluated. The primary outcome was clinical remission at 54 weeks, and we measured the serum GLM TLs at weeks 6, 10, and 14. Receiver operating characteristic (ROC) curves were constructed to identify optimal GLM TL thresholds early after induction therapy that were associated with clinical remission at week 54.

RESULTS

The GLM TL at week 14, but not at weeks 6 or 10, was significantly associated with clinical remission at week 54 (median [IQR] 1.6 [1.3-1.6] μg/mL vs. 0.9 [0.6-1.3] μg/mL; p = 0.04). The area under the ROC curve for GLM TLs at week 14 was 0.78. We identified a week-14 GLM TL of 1.1 μg/mL as the target threshold for achieving clinical remission at week 54.

CONCLUSION

Our results demonstrate the value of early serum GLM TLs in predicting the long-term outcomes of GLM for patients with UC.

Risk Factors for Nephrotoxicity due to Tacrolimus Therapy for Ulcerative Colitis

BACKGROUND AND AIMS

The calcineurin inhibitor tacrolimus is reportedly effective for moderate/severe ulcerative colitis (UC); however, it is also reportedly associated with nephrotoxicity. We investigated the risk factors for tacrolimus-induced nephrotoxicity and whether renal impairment adversely affected the outcomes of tacrolimus treatment in patients with UC.

METHODS

We conducted a retrospective study of 93 patients with UC who were administered tacrolimus leading to high trough levels (10-15 ng/mL) for 2 weeks and low trough levels (5-10 ng/mL) for 3 months.

RESULTS

Acute kidney injury (AKI) occurred in 44 patients (47.3%) during tacrolimus treatment. Of these patients, 34 (36.6%) developed AKI during the high trough phase and 17 (18.3%) developed AKI when the trough value exceeded the original target value of 15 ng/mL. Multivariate logistic regression analysis revealed that the male sex was significantly associated with AKI (p = 0.002, AOR = 4.38, 95% CI [1.69-11.3]). Clinical remission rate after 4, 8, 12, and 24 weeks of tacrolimus treatment in patients with AKI was lower than that in patients without AKI. Six patients (6.5%) had chronic kidney disease (CKD) after tacrolimus treatment completion, and all patients with CKD developed AKI during treatment. The median duration of treatment with no improvement in AKI was significantly longer in patients with CKD than in those without CKD (p = 0.016).

CONCLUSION

We revealed the risk factors for tacrolimus-induced nephrotoxicity. Renal impairment occurrence adversely affected the tacrolimus treatment outcome; therefore, it is important to carefully administer tacrolimus to prevent renal impairment.

Coexistence of oscillatory and reduced states on a spherical field controlled by electrical potential

The Belousov-Zhabotinsky (BZ) reaction was investigated to elucidate features of oscillations depending on the applied electrical potential, E. A cation-exchange resin bead loaded with the catalyst of the BZ reaction was placed on a platinum plate as a working electrode and then E was applied. We found that global oscillations (GO) and a reduced state coexisted on the bead at a negative value of E and that the source point of GO changed depending on E. The thickness of the reduced state was determined by a yellow colored region which corresponded to the distribution of Br₂. The present studies suggest that the distribution of the inhibitor, Br^-, which is produced from Br₂, plays an important role in the existence of the reduced state and GO, and the source point of GO.

An Adult Case of Sellar Atypical Teratoid/Rhabdoid Tumor Presenting with Lung Metastasis, Harboring a Compound Heterozygous Mutation in INI1

A typical teratoid/rhabdoid tumors (AT/RT) are highly malignant embryonal tumors in children that are associated with inactivation of the integrase interactor 1 (INI1) gene. Several adult cases of AT/RT have been reported, which were characterized by the sellar occurrence and predominantly occurred in females with INI1 mutation variants. However, clinical and genetic features are poorly understood in this unusual entity. We experienced a case of a 45-year-old female with sellar AT/RT presenting diplopia, who underwent subtotal removal of the tumor by the endoscopic endonasal transsphenoidal approach. Pathological diagnosis was AT/RT with INI1 inactivation on immunohistochemistry. Subsequently, multiple lung metastases were confirmed on fluorodeoxyglucose positron emission tomography (FDG-PET). Although she received postoperative chemoradiotherapy, she died of cerebrospinal fluid dissemination. Autopsy revealed cerebrospinal dissemination and lung metastasis of AT/RT. Biallelic alterations in the INI1 gene were identified by direct sequencing, harboring on different alleles (compound heterozygous mutations) was observed, which is the potential genetic pattern in adult AT/RT. Literature review indicated that lung metastasis frequently occurs in sellar AT/RTs, which is accompanied by cavernous sinus invasion. These observations suggested that cavernous sinus invasion causes haematogenous metastasis to the lung in sellar AT/RT. We discuss clinical and pathological features in adult sellar AT/RT to improve understanding of this unique entity.

Traveling waves propagating through coupled microbeads in the Belousov-Zhabotinsky reaction

Spatio-temporal patterns, namely global oscillations (GO) and traveling waves (TW), were investigated in spherical microbeads loaded with a catalyst for the Belousov-Zhabotinsky (BZ) reaction onto the surface (2D-loaded) or the entire volume of the bead (3D-loaded). GO and TW selectively appeared in the 2D- and 3D-loaded beads, respectively, placed on a polyethylene terephthalate (PET) sheet in the catalyst-free BZ solution. We examined two types of coupling of the two beads: 2D-3D and 3D-3D couplings. In both cases, synchronization occurred when the minimum distance between the two beads, l, was shorter than the threshold. Herein, we reported not only temporal information, that is, phase difference, but also spatial information, that is, the directions of the TW propagating through the coupled BZ beads. In the synchronization for the 2D-3D coupling, TW in the 3D-loaded bead were initiated from the point near the 2D-loaded bead as a pacemaker and propagated in the opposite direction. By contrast, the directions of the TW in the 3D-loaded bead changed depending on l in the synchronization for the 3D-3D coupling. These experimental results can be quantitatively reproduced by numerical calculations based on the diffusion dynamics of an activator of the BZ reaction. Our results suggest that the features of spatio-temporal wave propagation are indicative of the configuration of the oscillators.

Instability of the Homogeneous Distribution of Chemical Waves in the Belousov-Zhabotinsky Reaction

Chemical traveling waves play an important role in biological functions, such as the propagation of action potential and signal transduction in the nervous system. Such chemical waves are also observed in inanimate systems and are used to clarify their fundamental properties. In this study, chemical waves were generated with equivalent spacing on an excitable medium of the Belousov–Zhabotinsky reaction. The homogeneous distribution of the waves was unstable and low- and high-density regions were observed. In order to understand the fundamental mechanism of the observations, numerical calculations were performed using a mathematical model, the modified Oregonator model, including photosensitive terms. However, the homogeneous distribution of the traveling waves was stable over time in the numerical results. These results indicate that further modification of the model is required to reproduce our experimental observations and to discover the fundamental mechanism for the destabilization of the homogeneous-distributed chemical traveling waves.

Spontaneous Mode Switching of Self-Propelled Droplet Motion Induced by a Clock Reaction in the Belousov-Zhabotinsky Medium

Interfacial chemical dynamics on a droplet generate various self-propelled motions. For example, ballistic and random motions arise depending on the physicochemical conditions inside the droplet and its environment. In this study, we focus on the relationship between oxidant concentrations in an aqueous droplet and its mode of self-propelled motion in an oil phase including surfactant. We demonstrated that the chemical conditions inside self-propelled aqueous droplets were changed systematically, indicating that random motion appeared at higher concentrations of oxidants, which were H₂SO₄ and BrO₃^-, and ballistic motion at lower concentrations. In addition, spontaneous mode switching from ballistic to random motion was successfully demonstrated by adding malonic acid, wherein the initially observed reduced state of the aqueous solution suddenly changed to the oxidized state. Although we only observed one-time transition and have not yet succeeded to realize alternation between ballistic (reduced state) and random motion (oxidized state), such spontaneous transitions are fundamental steps in realizing artificial cells and understanding the fundamental mechanisms of life-like behavior, such as bacterial chemotaxis originating from periodical run-and-tumble motion.

pH-Sensitive Oscillatory Motion of a Urease Motor on the Urea Aqueous Phase

A self-propelled object coupled with an enzyme reaction between urease and urea was investigated at the air/aqueous interface. A plastic object that was fixed to a urease-immobilized filter paper was used as a self-propelled object, termed a urease motor, placed on an aqueous urea solution. The driving force of the urease motor is the difference in the surface tension around the object. Oscillatory motion or no motion was triggered depending on the initial pH of the urea solution. Both the frequency and maximum speed of the oscillatory motion varied depending on the initial pH of the water phase. The mechanisms underlying the oscillatory motion and no motion were discussed in relation to the bell-shaped enzyme activity of urease in the enzyme reaction and the surface tension around the urease motor.

GLI3 Is Associated With Neuronal Differentiation in SHH-Activated and WNT-Activated Medulloblastoma

Glioma-associated oncogene homolog 3 (GLI3), whose main function is to inhibit GLI1, has been associated with neuronal differentiation in medulloblastoma. However, it is not clear what molecular subtype(s) show increased GLI3 expression. GLI3 levels were assessed by immunohistochemistry in 2 independent cohorts, including a total of 88 cases, and found to be high in both WNT- and SHH-activated medulloblastoma. Analysis of bulk mRNA expression data and single cell RNA sequencing studies confirmed that GLI1 and GLI3 are highly expressed in SHH-activated medulloblastoma, whereas GLI3 but not GLI1 is highly expressed in WNT-activated medulloblastoma. Immunohistochemical analysis has shown that GLI3 is expressed inside the neuronal differentiated nodules of SHH-activated medulloblastoma, whereas GLI1/2 are expressed in desmoplastic areas. In contrast, GLI3 is diffusely expressed in WNT-activated medulloblastoma, whereas GLI1 is suppressed. Our data suggest that GLI3 may be a master regulator of neuronal differentiation and morphology in these subgroups.

Alternate Route Selection of Self-Propelled Filter Papers Impregnated with Camphor for Two-Branched Water Channels

The route selection of self-propelled filter papers impregnated with camphor for two-branched water channels was investigated. The two-branched water channel was composed of a stem channel and two branch channels, and the branch channels were connected to the stem channel at a junction. When a single camphor paper reached the junction from the stem channel, it selected one of the two routes equivalently. Three or five camphor papers which were placed on a stem channel exhibited either alternate or random route selection depending on the characteristic length between the leading and following papers, L_c. That is, the alternate route selection of the camphor papers for the two-branched water channels was observed at L_c ≤ 25 mm. By contrast, the alternate route selection was broken at L_c > 25 mm. The physicochemical meaning of the threshold value, L_th ∼ 26 mm, between the alternate and random route selections was discussed based on the experimental results. In addition, the distribution length of camphor molecules developed from the leading camphor paper and the change in the spatial gradient of surface tension around the junction supports the value of L_th. These results suggest that autonomous phenomena using inanimate self-propelled objects are important to understand collective motion in living organisms.

Switching between Two Oscillatory States Depending on the Electrical Potential

Various spatiotemporal patterns were created on the surface or in the body of cation-exchange resin beads which were loaded with the catalyst of the Belousov-Zhabotinsky (BZ) reaction. Either global oscillations (GO) or traveling waves (TW) and the switching between them were observed in the previous papers, but it was not clear how chemicals contribute to the reaction inside/around the BZ bead. In this paper, we scanned the electrical potential, E, from +1 to -1 V (negative scan) and then turned from -1 to +1 V (positive scan) to control the switching between GO and TW. We found that the electrical switching potential from TW to GO, E_TG, and from GO to TW, E_GT, depended on the scanning direction of E and the diameter of the bead, d. The present study suggests that the electrode-induced increase of the inhibitor, Br^-, and the activator, HBrO₂, around the BZ bead plays an important role in determining E_TG and E_GT.

BCOR Internal Tandem Duplication Expression in Neural Stem Cells Promotes Growth, Invasion, and Expression of PRC2 Targets

Central nervous system tumor with BCL6-corepressor internal tandem duplication (CNS-BCOR ITD) is a malignant entity characterized by recurrent alterations in exon 15 encoding the essential binding domain for the polycomb repressive complex (PRC). In contrast to deletion or truncating mutations seen in other tumors, BCOR expression is upregulated in CNS-BCOR ITD, and a distinct oncogenic mechanism has been suggested. However, the effects of this change on the biology of neuroepithelial cells is poorly understood. In this study, we introduced either wildtype BCOR or BCOR-ITD into human and murine neural stem cells and analyzed them with quantitative RT-PCR and RNA-sequencing, as well as growth, clonogenicity, and invasion assays. In human cells, BCOR-ITD promoted derepression of PRC2-target genes compared to wildtype BCOR. A similar effect was found in clinical specimens from previous studies. However, no growth advantage was seen in the human neural stem cells expressing BCOR-ITD, and long-term models could not be established. In the murine cells, both wildtype BCOR and BCOR-ITD overexpression affected cellular differentiation and histone methylation, but only BCOR-ITD increased cellular growth, invasion, and migration. BCOR-ITD overexpression drives transcriptional changes, possibly due to altered PRC function, and contributes to the oncogenic transformation of neural precursors.

Oscillatory Motion of a Camphor Object on a Surfactant Solution

The mode bifurcation between oscillatory motion and no motion of a camphor object floating on surfactant aqueous solution was investigated. The camphor and surfactant were used as the sources of driving and suppressing forces, respectively. A circular plastic sheet was attached to the center of the bottom of a camphor disk, which served as the self-propelled object; further, the contact area between the disk and the solution (S) was varied to control the amount of camphor molecules from the disk that dissolved in the solution. Motion features, that is, the maximum speed, frequency of oscillatory motion, and mode bifurcation, varied depending on S. We discussed the relationship between these motion features and the kinetics of camphor and surfactant molecules around the object. The results suggest that the nature of the oscillatory motion depends on the amount of camphor molecules accumulated at the base of the self-propelled object.

Ependymoma-like tumor with mesenchymal differentiation harboring C11orf95-NCOA1/2 or -RELA fusion: A hitherto unclassified tumor related to ependymoma

Recurrent fusion genes involving C11orf95, C11orf95‐RELA, have been identified only in supratentorial ependymomas among primary CNS tumors. Here, we report hitherto histopathologically unclassifiable high‐grade tumors, under the tentative label of “ependymoma‐like tumors with mesenchymal differentiation (ELTMDs),” harboring C11orf95‐NCOA1/2 or ‐RELA fusion. We examined the clinicopathological and molecular features in five cases of ELTMDs. Except for one adult case (50 years old), all cases were in children ranging from 1 to 2.5 years old. All patients presented with a mass lesion in the cerebral hemisphere. Histologically, all cases demonstrated a similar histology with a mixture of components. The major components were embryonal‐appearing components forming well‐delineated tumor cell nests composed of small uniform cells with high proliferative activity, and spindle‐cell mesenchymal components with a low‐ to high‐grade sarcoma‐like appearance. The embryonal‐appearing components exhibited minimal ependymal differentiation including a characteristic EMA positivity and tubular structures, but histologically did not fit with ependymoma because they lacked perivascular pseudorosettes, a histological hallmark of ependymoma, formed well‐delineated nests, and had diffuse and strong staining for CAM5.2. Molecular analysis identified C11orf95‐NCOA1, ‐NCOA2, and ‐RELA in two, one, and two cases, respectively. t‐distributed stochastic neighbor embedding analysis of DNA methylation data from two cases with C11orf95‐NCOA1 or ‐NCOA2 and a reference set of 380 CNS tumors revealed that these two cases were clustered together and were distinct from all subgroups of ependymomas. In conclusion, although ELTMDs exhibited morphological and genetic associations with supratentorial ependymoma with C11orf95‐RELA, they cannot be regarded as ependymoma. Further analyses of more cases are needed to clarify their differences and similarities.

A surfactant reaction model for the reciprocating motion of a self-propelled droplet

We report herein experimental observations of the reciprocating motion of a self-propelled droplet floating on the surface of an aqueous surfactant solution and a simple reaction model capable of reproducing the observed behavior of the droplet. The reciprocating motion was observed in a quasi-one-dimensional annular channel, so the reciprocation was not caused by reflections at boundaries. To understand the reciprocation, our model assumes a reaction between the surface active substance emitted from the droplet and surfactants dissolved in the aqueous solution. This reaction invokes an inversion of the surface tension gradient and thus the droplet's reciprocation. We show that the model can reproduce experimental results semi-quantitatively using numerical simulations with realistic parameters.

Charge Density Waves in YBa_{2}Cu_{3}O_{6.67} Probed by Resonant X-Ray Scattering under Uniaxial Compression

We report a comprehensive Cu L_{3}-edge resonant x-ray scattering (RXS) study of two- and three-dimensional (2D and 3D) incommensurate charge correlations in single crystals of the underdoped high-temperature superconductor YBa_{2}Cu_{3}O_{6.67} under uniaxial compression up to 1% along the two inequivalent Cu─O─Cu bond directions (a and b) in the CuO_{2} planes. We confirm the strong in-plane anisotropy of the 2D charge correlations and observe their symmetric response to pressure: pressure along a enhances correlations along b, and vice versa. Our results imply that the underlying order parameter is uniaxial. In contrast, 3D long-range charge order is only observed along b in response to compression along a. Spectroscopic RXS measurements show that the 3D charge order resides exclusively in the CuO_{2} planes and may thus be generic to the cuprates. We discuss implications of these results for models of electronic nematicity and for the interplay between charge order and superconductivity.

ATRT-17. TARGETING GLUTAMINE METABOLISM LOWERS METHYLATION POTENCIALS IN AT/RT AND SYNERGIZE WITH TAZEMETOSTAT

Atypical teratoid/rhabdoid tumors (AT/RT) have a single recurring genetic mutation in SMARCB1. This deletion leads to an abnormal SWI/SNF chromatin remodeling complex and the constitutive activation of EZH2. S-adenosyl-L-methionine (SAM) donates a methyl group to EZH2 which then methylates DNA and histones leading to the abnormal gene expression responsible for AT/RT’s aggressive phenotype. We have previously shown that glutamine metabolic inhibition with 6-diazo-5-oxo-L-norleucine (DON) confers a survival advantage in AT/RT. In this study, we identified with ultra-high performance liquid chromatography mass spectrometry that DON treatment lowered the methylation potential in AT/RT (Decreased SAM:SAH ratio, t-test in 5 AT/RT human-derived cell models comparing DON treatment to DMSO control, p<0.05). AT/RT cell lines grown in glutamine deplete media compared to normal growth conditions also had a reduced methylation potential (decreased SAM:SAH, t-test, p<0.05). DON treatment over 5 days decreased histone methylation (as determined by western blot for H3K27me3). Tazemetostat is a small molecule inhibitor that blocks the SAM methyl donor site on EZH2. We find that DON combines synergistically with Tazemetostat to slow AT/RT cell growth (MTS assay, p<0.01 t-test; MUSE viability assay, p<0.01 ANOVA) and enhances cytotoxicity (MUSE Annexin-V, p<0.01 by ANOVA). Synergies were especially pronounced at low concentrations of Tazemetostat which is significant given that Tazemetostat’s efficacy in AT/RT has been limited by poor CNS penetration. These studies identify a novel treatment strategy that has potential to improve survival in AT/RT.

MODL-04. MODELING CNS HGNET-BCOR PATHOGENESIS USING NEURAL STEM CELLS

Central nervous system high-grade neuroepithelial tumor with BCL6-corepressor alteration (CNS HGNET-BCOR) is a recently identified entity characterized by internal tandem duplication (ITD) of BCOR, a core component of polycomb repressive complex (PRC) 1.1. BCOR-ITD exclusively occurs within an essential binding domain, suggesting aberrant epigenetic activities as a possible mechanism of gliomagenesis; however, the effect of this alteration on the transcriptome and DNA methylation are poorly understood. We have generated new CNS HGNET-BCOR models by lentiviral transduction of the BCOR-ITD into human and murine neural stem cells. In the human model, qRT-PCR and subsequent RNA-seq identified a transient derepression of PRC2-target genes comparing to an isogenic model with overexpression of wildtype-BCOR. A similar effect was found in clinical specimens from previous studies. In the murine-cell model, we confirmed increased clonogenicity in soft-agar assays, and tumors developed in mice flanks. Global DNA methylation levels evaluated by ELISA were significantly lower than those of parent cells, and 177 genes were differentially expressed on RNA-seq analysis comparing to BCOR-overexpressing control cells, including upregulation of known oncogenes. These results suggest that BCOR-ITD and associated alterations in the function of PRC1.1 affect methylation patterns in neural stem cells, driving transcriptional changes and oncogenic transformation into CNS HGNET-BCOR. More detailed analyses, including methylation arrays comparisons with clinical samples and in-silico drug sensitivity testing, are being performed.

Increased Tau Expression Correlates With IDH Mutation in Infiltrating Gliomas and Impairs Cell Migration

Although the microtubule-associated protein tau is well studied in human neurodegeneration, the role of tau in neoplastic brain diseases is not well understood. Recently, studies have shown tau mRNA expression is associated with improved survival in human infiltrating gliomas. However, the biologic basis of this association is largely unexplored. Using 2 independent publicly available mRNA databases, we show that high tau mRNA expression is associated with improved patient survival in infiltrating gliomas. Higher tau protein expression is also associated with improved patient prognosis in infiltrating gliomas by immunohistochemical staining of tissue microarrays. This prognostic association is in part due to higher tau mRNA and protein expression in IDH-mutant infiltrating astrocytomas. Expression of tau in an IDH-wildtype glioblastoma cell line selectively impairs cell migration in assays designed to mimic tumor invasion. These findings suggest that tau expression is not only associated with IDH mutation status but also may contribute to improved patient outcomes by impairing tumor invasion.

Self-Propelled Motion of a Camphor Disk on a Nervonic Acid Molecular Layer and Its Dependence on Phase Transition

We studied the self-propelled motion of a camphor disk placed on water developed with a nervonic acid molecular layer to investigate the dependence of types of motion on the properties of amphiphilic compounds. The surface pressure (Π) versus area (A) isotherm exhibited a transition point corresponding to a phase transition between the fluid (F) and fluid/condensed (F/C) phases of nervonic acid. The type of motion was determined by not only the surface pressure of the nervonic acid molecular layer but also the phase, either F or F/C. When the temperature of water was varied through the phase transition temperature T_p40 (∼23 °C), with an area of 40 Ų per nervonic acid molecule in the molecular layer, no motion and oscillatory motion were observed reversibly above and below T_p40, respectively. Our results suggest that the features of camphor motion depend on not only the surface pressure but also the nature of the phase in the nervonic acid molecular layer.

Inversion probability of three-bladed self-propelled rotors after forced stops of different durations

We investigated self-propelled rotation of a symmetric three-bladed rotor on water under periodic halt and release operations. The rotation was driven by the difference in the surface tension around the blades of the rotor because camphor molecules developed from three camphor disks glued at the blade ends. Spontaneous inversion of rotation direction was observed after a forced stop of the rotor and the subsequent release. The probability of such inversion decreased with an increase in the halting time. The asymmetric distribution of camphor molecules around the blades was also inverted after the forced stop and the degree of asymmetry increased with an increase in the angular velocity characterizing the stationary rotation of the rotor. Our experimental results for rotors with different shapes indicate that there is a strong correlation between the stationary angular velocity of the rotor and the maximum time duration of the forced stop for which a high probability of inversion is observed.