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Abstract Biodegradable poly(L-lactide)-b-poly(ethylene glycol)-b-poly(L-lactide) (PLLA-PEG-PLLA) triblock copolymer could potentially be used in bioplastic applications because it is more flexible than PLLA. However, investigations into modifying PLLA-PEG-PLLA with effective fillers are still required. In this work, bamboo biochar (BC) was used as an eco-friendly and cost-effective filler for the flexible PLLA-PEG-PLLA. The influences of BC addition on crystallization properties, thermal stability, hydrophilicity, and mechanical properties of the PLLA-PEG-PLLA were explored and compared to those of the PLLA. The PLLA-PEG-PLLA matrix and BC filler were found to have strong interfacial adhesion and good phase compatibility, while the PLLA/BC composites displayed weak interfacial adhesion and poor phase compatibility. For the PLLA-PEG-PLLA, the addition of BC induced a nucleation effect that was characterized by a decrease in the cold crystallization temperature from 76 to 71–75 °C and an increase in the crystallinity from 18.6 to 21.8–24.0%; however, this effect was not observed for the PLLA. When compared to pure PLLA-PEG-PLLA, the PLLA-PEG-PLLA/BC composites displayed greater thermal stability, tensile stress, and Young’s modulus. Temperature at maximum decomposition rate (Td,max) of PLLA end-blocks increased from 315 to 319–342 °C. Ultimate tensile stress of PLLA-PEG-PLLA matrix improved from 14.5 to 16.2–22.6 MPa and Young’s modulus increased from 220 to 280–340 MPa. Based on the findings, the crystallizability, thermal stability, and mechanical properties of the flexible PLLA-PEG-PLLA bioplastic were all enhanced by the use of BC as a multi-functional filler.

The rheological properties of a polyamide (PA) resin with low crystallinity were modified by melt-mixing it with a small amount of an alternative α-olefin–maleic anhydride copolymer as a reactive compound. Because PA has a low melting point, rheological characterization was performed over a wide temperature range. Owing to the reaction between PA and the alternative α-olefin–maleic anhydride copolymer, the blend sample behaved as a long-chain branched polymer in the molten state. The thermo-rheological complexity was obvious owing to large flow activation energy values in the low modulus region, i.e., the rheological time–temperature superposition principle was not applicable. The primary normal stress difference under steady shear was greatly increased in the wide shear rate range, leading to a large swell ratio at the capillary extrusion. Furthermore, strain hardening in the transient elongational viscosity, which is responsible for favorable processability, was clear. Because this is a simple modification method, it will be widely employed to modify the rheological properties of various polyamide resins.

Ovarian squamous cell carcinoma (SCC) is rare, and most cases arise from ovarian teratomas. Herein, we present a case of ovarian SCC arising from an ovarian seromucinous borderline tumor (SMBT) with squamous overgrowth. A 71-year-old woman an underwent emergency laparotomy due to the rupture of a right ovarian tumor suspected to be a borderline or malignant tumor. We performed a total abdominal hysterectomy, bilateral salpingo-oophorectomy, and partial omentectomy. The postoperative diagnosis was stage IC3 ovarian SCC arising from the SMBT with a squamous overgrowth. Subsequently, she underwent six cycles of combination therapy comprising paclitaxel and carboplatin. Two months after the last chemotherapy treatment, she presented with back pain. A CT scan showed a 14 mm pelvic tumor affecting the ureter, leading to right hydronephrosis. The patient underwent tumor resection and ureteroureterostomy. The pathological diagnosis was keratinizing SCC, representing ovarian cancer recurrence. Eight months after the removal of the recurrent tumor, we found a 35 mm recurrent pelvic tumor causing right hydronephrosis. Additionally, a 20 mm pleural dissemination was identified. Comprehensive genome profiling of recurrent tumor revealed genomic abnormalities in TP53, ARID1A, PTEN, PIK3R1, and CDKN2A/2B. Regarding immunotherapy biomarkers, the microsatellite instability test result was negative, the tumor mutation burden was low, and PD-L1 was highly expressed. The patient was referred to another hospital for participation in an immunotherapy clinical trial for ovarian SCC. This case indicates that refractory ovarian SCC can arise from SMBT. Further evaluation of additional cases is required to identify the molecular biological characteristics of ovarian SCC.

AbstractObjectives Although the Pipelle endometrial biopsy is widely performed as a practical and minimally invasive test for endometrial disease(s), its effectiveness in ovarian cancer has not been explored. The aim of the present study was to evaluate the results of Pipelle endometrial biopsy for ovarian, fallopian tube, and peritoneal cancers.Methods A pre-treatment Pipelle-endometrial biopsy was performed in 90 patients with ovarian, fallopian tube, or peritoneal cancers between January 2014 and November 2021. We retrospectively analysed the association between the results of Pipelle endometrial biopsy and clinicopathological data. Moreover, we evaluated their impact on the following treatment in advanced cases initially treated with chemotherapy.Results The sensitivity and false-negative rates for Pipelle endometrial biopsy were 25/90 (27.8%) and 65/90 (72.2%) in all patients, respectively, and 23/56 (41.0%) and 33/56 (58.9%) in cases with advanced disease (stages III and IV), respectively. Pipelle-positive endometrial biopsy-positive (Pipelle-positive) was not observed in 29 patients with clinical stage I disease, and Pipelle-positive patients exhibited significantly more high-grade serous carcinomas, and positive peritoneal, endometrial, and cervical cytologies than Pipelle-endometrial biopsy-negative cases. Surgical pathology was confirmed in 23 Pipelle-positive patients, and 17/23 (74.0%) had the same diagnosis as that for Pipelle endometrial biopsy. Conversely, 6/23 (26.0%) patients exhibited a minor diagnostic discrepancy between Pipelle endometrial biopsy and surgical pathology. Nineteen of the 38 (50.0%) patients initially treated with chemotherapy were identified as Pipelle-positive, contributing to a prompt histological diagnosis and pre-treatment tumour sampling. Companion diagnostic tests were performed using Pipelle endometrial biopsy samples from 4 inoperable patients.Conclusion Although the positive rate of Pipelle endometrial biopsy in ovarian, fallopian tube, and peritoneal cancers is low, Pipelle endometrial biopsy may enable prompt histological diagnosis and initiation of chemotherapy while collecting tumour tissue for genetic testing in some cases with advanced disease.

Abstract The effect of thermal and shear histories on the crystallization rate of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) was studied. As with other crystalline polymers, the shear history greatly affected the crystallization rate when the shear rate was beyond a critical value, i.e., the inverse of the Rouse relaxation time. Even after the formation of extended chain crystals, spherulite texture was clearly discernable. It grew from certain points on the extended chain crystals. Consequently, a row of spherulites appeared along the flow direction. The resin temperature in the molten state was also significant. When the sample was heated to 170 °C, which is beyond the main melting peak in the differential scanning calorimetry curve, unmolten crystals did not affect the linear viscoelastic properties. They acted as effective nucleating agents for the rest of the polymer during cooling. Therefore, the shear history hardly affected the crystallization rate and the number of spherulites.

Abstract Background Nerve invasion (N‐inv) is an important prognostic factor in pancreatic ductal adenocarcinoma (PDAC). Elucidation of circulating N‐inv stimulators could provide deeper insights and novel perspectives for PDAC therapy. The interleukin (IL)‐6/gp130 axis was evaluated in this study as a candidate N‐inv stimulator. Methods A human pancreatic cancer (PC) cell, Capan‐1, was confirmed to have the stimulant activity of IL‐6/gp130 axis through the evaluation of mRNA, cell surface protein and intracellular protein levels and chemotaxis and wound healing assay. The upregulation of IL‐6/gp130 axis was evaluated using tumor‐derived IL‐6 level and intratumoral pSTAT3 expression in N‐inv of murine sciatic nerves by intraneural injection of Capan‐1 cell (N‐inv model) and using resected pancreatic cancer tissue and clinical data from 46 PDAC patients. Results mRNA and protein expressions of IL‐6 and IL‐6 receptor were found in whole cell lysate and condition medium from PC cell. Cell surface protein expression of gp130 were clearly detected on PC cell. IL‐6 promoted migration and chemotaxis of PC cell. Serum IL‐6 and tumoral IL‐6 mRNA levels in N‐inv model mice were significantly higher than those in subcutaneous tumor mice (p = 0.004 and p = 0.002, respectively). Silencing of IL‐6 and gp130 on PC cell and administration of an anti‐IL‐6 receptor antibody, tocilizumab, suppressed N‐inv, compared to each control (p = 0.070, p = 0.118 and p = 0.122, respectively). In PDAC patients, the high‐N‐inv group showed poor prognosis (p =0.059) and elevated serum levels of IL‐6 and C‐reactive protein, synthesis of which is promoted by IL‐6, compared to those in the low‐N‐inv group (p = 0.006 and p = 0.075, respectively). Tumoral gp130 expression at N‐inv was higher than that in the primary pancreatic tumor (p = 0.026). Conclusion Biological activity of IL‐6/gp130 axis promoted N‐inv in murine model and was upregulated in PDAC patients with severe N‐inv. This study is the first evidence that the IL‐6/gp130 axis offers a potential therapeutic target in PDAC with N‐inv.

WL 17 is a Class I object and was considered to have a ring–hole structure. We analyzed the structure around WL 17 to investigate the detailed properties of this object. We used Atacama Large Millimeter/submillimeter Array archival data, which have a higher angular resolution than previous observations. We investigated the WL 17 system with the 1.3 mm dust continuum and ^12 CO and C ^18 O ( J = 2–1) line emissions. The dust continuum emission showed a clear ring structure with inner and outer edges of ∼11 and ∼21 au, respectively. In addition, we detected an inner disk of

Background: Chondrosarcoma is a common form of malignant bone tumor with limited treatment options. Approximately half of chondrosarcomas harbor gain-of-function mutations in isocitrate dehydrogenase (IDH), and mutant IDH produces 2-hydroxyglutarate (2-HG), which is an oncometabolite that contributes to malignant transformation. Therefore, inhibiting 2-HG production is a novel and promising treatment for advanced chondrosarcoma. 2-HG is also expected to be a useful biomarker for the diagnosis and treatment of IDH-mutant tumors. However, few studies have confirmed this using chondrosarcoma clinical specimens. Non-invasive monitoring of 2-HG levels is useful to infer that mutant IDH inhibitors reach therapeutic targets and to confirm their therapeutic efficacy in clinical practice. Methods: To evaluate the clinical utility of 2-HG as a surrogate biomarker for diagnosis and therapeutic efficacy, we measured intra-tumor and serum levels of 2-HG using frozen tissues and peripheral blood from patients with chondrosarcoma. We also developed a non-invasive method to detect intra-tumor 2-HG signals in vivo using magnetic resonance spectroscopy (MRS) Results: Both intratumoral and serum 2-HG levels were significantly elevated in IDH-mutant tumors, and these levels correlated with decreased survival. Furthermore, we detected intratumoral 2-HG peaks using MR spectroscopy in a xenograft model of IDH-mutant chondrosarcoma, and observed that 2-HG peak signals disappeared after administering an inhibitor of mutant IDH1. Conclusions: Our findings suggest that both intratumoral and serum 2-HG levels represent potentially useful biomarkers for IDH-mutant tumors and that the 2-HG signal in MR spectra has potential value as a non-invasive biomarker. Taken together, these findings may positively impact the clinical development of mutant IDH inhibitors for the treatment of advanced chondrosarcoma.

Abstract Background Malignancy during pregnancy is increasing, and the most common type of malignancy is uterine cervical cancer. When planning the treatment of cervical cancer, it is important to look for signs of metastasis before surgery, especially metastasis to the lymph nodes. In this report, we assessed the diagnostic value of positron emission tomography/magnetic resonance imaging (PET/MRI) for evaluating cervical cancer propagation before surgery, with a focus on pregnant women. Case presentation 18F Fluorodeoxyglucose (FDG)-PET/MRI was performed in seven pregnant cervical cancer patients (28–34 years old) at 9–18 gestational weeks. In case #5, a second PET/MRI was performed at 24 gestational weeks. Of seven FDG-PET/MRI examination series in six cases (cases #1–6), FDG-PET/MR imaging could detect cervical tumors with abnormal FDG accumulation; these tumors were confirmed with a standardized uptake value max (SUV max) titer of 4.5–16. A second PET/MRI examination in case #5 revealed the same SUV max titer as the first examination. In these six imaging series (cases #1–5), there were no signs of cancer metastasis to the parametrium and lymph nodes. However, in case #6, abnormal FDG accumulation in the left parametrial lymph nodes was also detectable. Pathological examination showed lymph node metastasis in case #6. In case #7, PET/MRI could not detect any abnormal FDG accumulation in the cervix and other sites. Cone biopsy demonstrated only micro-invasive squamous cell carcinoma. After treatment for cervical cancer, all seven patients have had no recurrence of disease within the follow-up period (2.8–5.6 years), and their children have developed appropriately. Conclusion PET/MRI is an effective imaging tool to evaluate cervical cancer progression in pregnancy.

Abstract Background We report a case of pulmonary edema induced by tocolytic agents that was successfully managed with noninvasive positive-pressure ventilation (NPPV) and resulted in extended gestation. Case presentation A 36-year-old Japanese pregnant woman received tocolytic therapy with ritodrine hydrochloride, magnesium sulfate, nifedipine, and betamethasone from 28 weeks of gestation. She developed respiratory failure. and her chest X-ray showed enlarged pulmonary vascular shadows. At 29 weeks and 1 day of gestation, she was diagnosed with pulmonary edema induced by tocolytic agents. Because respiratory failure worsened 2 days after ritodrine hydrochloride and magnesium sulfate were stopped, NPPV was initiated. Her respiratory status improved and she was weaned off of NPPV after 3 days. She underwent cesarean section because of breech presentation at 30 weeks and 0 days of gestation due to initiation of labor pains. Conclusions NPPV can be safely administered in cases of tocolytic agent-induced pulmonary edema during pregnancy.

The effect of shear history on structure development during post-processing annealing was studied using poly(lactic acid) PLA. Since PLA shows a low crystallization rate, quenched films had no crystallinity. Moreover, molecular orientation was not detected in the films. During the annealing procedure beyond its glass transition temperature, however, molecular orientation to the flow direction occurred with the crystallization growth in the films having an appropriate shear history. This peculiar crystal growth during the annealing was most probably attributed to the crystallization from extended chain crystals generated during the applied shear history, although the amount of extended chain crystals was low. The results obtained in this study should be noted because the molecular orientation proceeded due to the annealing history applied. Furthermore, this phenomenon will be used to suppress dimensional change and increase product rigidity.

The rheological properties and processability at injection molding were studied for bisphenol-A polycarbonate (PC) that was modified by low-density polyethylene (LDPE) having a low shear viscosity. The LDPE addition significantly decreased the steady-state shear viscosity, especially in the high shear rate region. The decrease did not originate from slippage on the die wall but due to interfacial slippage between the PC and dispersed LDPE droplets that deformed to the flow direction to a great extent. As a result of the viscosity decrease, injection pressure largely decreased from 150 to 110 MPa with the addition only 5 wt.% of LDPE. The enhanced flowability also reduced the warpage of the molded product significantly, demonstrating that the processability at injection molding was improved by the addition of LDPE.

Mechanical responses after the uniaxial deformation of graded styrene–butadiene rubber (SBR) with a gradient in the crosslink points in the thickness direction were investigated as compared with those of homogenously vulcanized SBR samples. The elongational residual strain of a graded sample was found to depend on the part with a high crosslink density. Therefore, it showed good rubber elasticity. After stress removal, moreover, the graded sample showed a marked warpage. This suggested that shrinking stress acted on the surface with a high crosslink density, which would avoid a crack growth on the surface. The sample shape was then recovered to be flat very slowly, indicating that the shrinking stress worked for a long time. This unique rubber elasticity, i.e., slow strain recovery with an excellent strain recovery, makes graded rubber highly significant.

In this paper, the structure and properties of transparent films composed of bisphenol-A polycarbonate (PC) and a commercially available copolyester, poly(1,4-cyclohexanedimethanol-co-2,2,4,4-tetramethyl-1,3-cyclobutanediol-co-terephthalate) (CPE), were studied. Both PC and CPE films are known to be transparent with good mechanical toughness. It was found that PC/CPE (50/50) showed miscibility in both the molten and solid states, indicating that there is a high possibility for the blend system to be miscible in the whole blend ratios. Because of the miscibility, the blend films showed no light scattering originating from phase separation. The mechanical properties of the films, such as Young’s modulus, yield stress, and strain at break, were determined by the blend ratio, and the glass transition temperature increased with the PC content, which corresponded well with the values predicted by the Fox equation. These results demonstrate that the thermal and mechanical properties of the films can only be controlled by the blend ratio. Since these transparent films showed excellent mechanical toughness irrespective of the blend ratios, they can be employed in various applications.

The effects of pressure and shear rate on the miscibility of binary blends comprising bisphenol-A polycarbonate (PC) and low molecular weight poly(methyl methacrylate) (PMMA) were investigated using a capillary rheometer. Both pressure and shear rate affected the miscibility. The examination of an extruded strand of the blend provided information about the cause of the phase change. Under high pressure, pressure-induced demixing occurred at temperatures below the lower critical solution temperature (LCST) of the blend. Consequently, the extruded strand became opaque throughout. During shear-induced mixing/demixing, a part of the strand became opaque because of the distribution of the shear rate in the strand. For example, during shear-induced demixing, only the exterior of the strand, i.e., the high shear rate region, became opaque. Above the LCST, shear-induced mixing occurred, and only the center region of the strand became opaque.

Miscible blends composed of bisphenol-A polycarbonate (PC) and poly(methyl methacrylate) (PMMA), in which one of them has low molecular weight, were employed to study the surface segregation behavior during flow. The blend samples showed typical rheological behaviors, such as simple polymer melts without a long-time relaxation mechanism ascribed to phase separation, demonstrating that they were miscible. After injection molding, the amounts of a low molecular weight component on the blend surface were found to be larger than the actual blend ratio. Because the injection-molded products were transparent despite a huge difference in refractive indices between PC and PMMA, they showed no phase separation. This result demonstrated that surface segregation of a low molecular weight component occurred under flow field, which expands the material design such as tough plastics with good scratch resistance and optical fibers with tapered refractive index.

Viscoelastic properties including melt processability were evaluated for a fully biomass-based glassy plastic comprising cellulose acetate (CA) and triethyl citrate (TEC). The TEC exerted an excellent plasticizing effect without dissolving the CA crystals. Pure CA has poor melt processability. In contrast, the TEC-plasticized CA had good melt-processability at 205 °C, which is lower than the degradation temperature of CA. Extrusion was possible even at 1000 s−1 without any flow instabilities, similar to conventional plastics showing good processability at extrusion. Furthermore, there was marked strain-hardening behavior in the transient elongational viscosity, suggesting that various processing operations are possible, such as a long-chain branched polymer. This biomass-based plastic can be used as a substitute for conventional glassy plastics because it is highly transparent and its softening temperature is above 100 °C.

The effects of the ultra-high-molecular-weight (UHMW) component of polypropylene (PP) on its rheological properties, crystallization behavior, and solid-state mechanical properties were investigated using various measurement techniques. The terminal relaxation time—determined by measuring the linear viscoelasticity—was increased by adding the UHMW component. The increase in the melt elasticity produced by adding the UHMW component was observed by measuring the steady-state shear flow, although the shear viscosity was not greatly affected. Owing to the long characteristic time of the Rouse relaxation of the UHMW component, PP with the UHMW component formed highly oriented structures through a shear-induced crystallization process. The addition of the UHMW component enhanced the orientation and regularity of crystalline structure for extruded films. Therefore, the Young′s modulus, yield stress, and strength were higher in the PP film containing the UHMW component than in one without the UHMW component, irrespective of the direction of tensile deformation.

The effects of magnesium salts with various anion species on the structure and properties of a poly(vinyl alcohol) (PVA) film were studied. The glass transition temperature of the PVA film increased following the addition of a magnesium salt. Furthermore, the salt greatly enhanced the modulus and yield stress and reduced the crystallinity of the film. These effects were attributed to the strong ion–dipole interactions between the magnesium salts and the PVA chains. The strength of interaction, i.e., the reduction of segmental motions, depended on the anion species in the following order: Mg(ClO4)2, MgBr2, MgCl2, Mg(CH3COO)2, and MgSO4. The order corresponded to the Hofmeister series, which predicts the ability to break the structure of water.

In this study, Kraft lignin was esterified with phthalic anhydride and was served as reinforcing filler for poly(butylene succinate) (PBS). Composites with different ratios of PBS, lignin (L), modified lignin (ML) and kenaf core fibers (KCF) were fabricated using a compounding method. The fabricated PBS composites and its counterparts were tested for thermal, physical and mechanical properties. Weight percent gain of 4.5% after lignin modification and the FTIR spectra has confirmed the occurrence of an esterification reaction. Better thermo-mechanical properties were observed in the PBS composites reinforced with modified lignin and KCF, as higher storage modulus and loss modulus were recorded using dynamic mechanical analysis. The density of the composites fabricated ranged from 1.26 to 1.43 g/cm3. Water absorption of the composites with the addition of modified lignin is higher than that of composites with unmodified lignin. Pure PBS exhibited the highest tensile strength of 18.62 MPa. Incorporation of lignin and KCF into PBS resulted in different extents of reduction in tensile strength (15.78 to 18.60 MPa). However, PBS composite reinforced with modified lignin exhibited better tensile and flexural strength compared to its unmodified lignin counterpart. PBS composite reinforced with 30 wt% ML and 20 wt% KCF had the highest Izod impact, as fibers could diverge the cracking propagation of the matrix. The thermal conductivity value of the composites ranged from 0.0903 to 0.0983 W/mK, showing great potential as a heat insulator.

The effects of neutralizer species on the transparency of injection-molded plates were studied using isotactic polypropylene (PP) containing a crystal nucleating agent—i.e., 1,3:2,4-bis-o-(4-methylbenzylidene)-d-sorbitol (MDBS). A plate containing lithium stearate (StLi) was more transparent than one containing calcium stearate (StCa) when the MDBS content was 0.1 wt. %. The addition of StLi accelerated the formation of MDBS fibers and the crystallization of PP. However, when the MDBS content was 1.0 wt. %, StCa improved the transparency more effectively than StLi. These results indicate that the combination of an appropriate amount of MDBS and the correct neutralizer species is critical for enhancing the transparency of injection-molded PP plates.

Thermoplastic vulcanizate (TPV) has excellent elastomeric properties and can be reprocessed multiple times. TPV is typically produced by using the dynamic vulcanization (DV) method in which rubber is crosslinked simultaneously with thermoplastics. Peroxide-crosslinked TPV can increase the compatibility between rubber and thermoplastics but loses its reprocessability due to excess crosslinking in the latter. In this work, we overcome this obstacle by using a two-step mixing method to prepare fully crosslinked elastomers of ethylene vinyl acetate copolymer (EVA) and natural rubber (NR). Each sample formulation was prepared with three different mixing methods for comparison: NR-DV, Split-DV, and All-DV. For NR-DV, NR was crosslinked prior to the addition of EVA together with the thermal stabilizer (TS). For Split-DV, a small amount of EVA and NR was crosslinked prior to the addition of EVA and TS. In the All-DV method, EVA and NR were crosslinked, and then TS was added. The appearance and processability of the samples were affected by the degree of crosslinking. NR-DV showed a non-homogeneous texture. Although the samples of the All-DV method appeared homogeneous, their mechanical and rheological properties were inferior to those of the Split-DV method. The mechanical properties of the Split-DV samples were not significantly changed after reprocessing 10 times. Therefore, Split-DV is the preferred method for TPV production.

Orientation birefringence and its wavelength dispersion are studied for hot-drawn films of cellulose esters such as cellulose triacetate (CTA), cellulose diacetate (CDA), and cellulose acetate propionate (CAP) exposed to three different humidities of environments. Hot-drawn CTA films show negative birefringence that decreases with increasing wavelength. On the other hand, CDA and CAP films show positive birefringence that increases with increasing wavelength, i.e., the so-called extraordinary wavelength dispersion of birefringence. Upon exposure to high humidity environment, the orientation birefringence of CDA and CAP decreases. The decrease is prominent for the samples containing a large amount of water. CTA, however, shows an increase in magnitude of its negative orientation birefringence with increasing moisture content. The results can be explained by the increase of the polarizability anisotropy perpendicular to the stretching direction in the cellulose esters. It is found from ATR-FTIR measurements that hydrogen bonds are formed between carbonyl groups of cellulose esters and water molecules. Considering that orientation birefringence of cellulose esters is determined mainly by ester groups, the formation of hydrogen bonds contributes to the polarizability anisotropy, thus affecting the orientation birefringence.