GFN-xTB-Based Computations Provide Comprehensive Insights into Emulsion Radiation-Induced Graft Polymerization.

Invited for this month's cover are the collaborating groups of Dr. Ryohei Kakuchi and Ms. Kiho Matsubara at Gunma University, Japan, Prof. Kei Takahashi at Fukuoka Institute of Technology and The Institute of Statistical Mathematics, Japan, Prof. Takeshi Matsuda at Hannan University, Japan, Dr. Noriaki Seko and Dr. Yuji Ueki at National Institutes for Quantum Science and Technology, Japan. The cover picture shows the machine learning-based optimization and interpretation of radiation-induced graft polymerizations under emulsion conditions based on realistic information for monomers calculated by the state-of-the-art semiempirical method. More information can be found in the Research Article by Kiho Matsubara, Kei Takahashi, Ryohei Kakuchi, and co-workers.

GFN-xTB-Based Computations Provide Comprehensive Insights into Emulsion Radiation-Induced Graft Polymerization.

In this article, a deep insight into emulsion radiation-induced graft polymerization (RIGP) was obtained by computing explicit solvation free energies, conformational entropy, monomer radius and dipole moments with the state-of-the-art Conformer-Rotamer Ensemble Sampling Tool (CREST) package primarily at semiempirical GFN-xTB level. By leveraging the robustness of the CREST package, above parameters provided dynamic nature of methacrylate monomers with the consideration of realistic emulsion conditions. With the chemical and physical importance of the above results, CREST-determined explanatory variables sufficiently led to the building of the prediction models for the RIGP of methacrylate monomers. The machine learning model building resulted in effective reactivity predictions and unveiled important factors for the radiation-induced graft polymerization in a chemically interpretable fashion.

Boron neutron capture therapy using cyclotron-based epithermal neutron source and borofalan (10B) for recurrent or locally advanced head and neck cancer (JHN002): An open-label phase II trial.

BACKGROUND AND PURPOSE: Boron neutron capture therapy (BNCT) can be performed without reactors due to development of cyclotron-based epithermal neutron source (C-BENS), which is optimized for treatment for deeper-seated tumors. The purpose of this study was to evaluate efficacy and safety of cyclotron-based BNCT with borofalan (10B) for recurrent or locally advanced head and neck cancer. MATERIALS AND METHODS: In this open-label, phase II JHN002 trial of BNCT using C-BENS with borofalan (10B), patients with recurrent squamous cell carcinoma (R-SCC) or with recurrent/locally advanced non-squamous cell carcinoma (R/LA-nSCC) of the head and neck were intravenously administered 400 mg/kg borofalan (10B), followed by neutron irradiation. The tumor dose was determined passively as the mucosal maximum dose of 12 Gy-Eq. The primary endpoint was the objective response rate (ORR). Post-trial observational JHN002 Look Up study was planned for evaluating locoregional progression-free survival (LRPFS). RESULTS: Eight R-SCC and 13 R/LA-nSCC patients were enrolled. All R-SCC patients had prior radiotherapy with a median dose of 65.5 Gy (range, 59.4-76.0 Gy). The ORR for all patients was 71%, and complete response/partial response were 50%/25% in R-SCC and 8%/62% in R/LA-nSCC. The 2-year overall survival for R-SCC and R/LA-nSCC were 58% and 100%, respectively. The median LRPFS was 11.5 months for R-SCC. Frequently observed adverse events included alopecia (95%), hyperamylasemia (86%), and nausea (81%). CONCLUSION: These data suggest that BNCT using C-BENS with borofalan (10B) is a promising treatment option for patients with R-SCC or R/LA-nSCC of the head and neck.

Synthesis of Fibrous Metal Adsorbent with a Piperazinyl-Dithiocarbamate Group by Radiation-Induced Grafting and Its Performance.

A fibrous grafted metal adsorbent with a piperazinyl-dithiocarbamate (PZ-DTC) group was synthesized by radiation-induced emulsion grafting of glycidyl methacrylate onto a polyethylene-coated polypropylene nonwoven fabric (PE/PP-NF) and subsequent three-step chemical modifications consisting of amination with N-(tert-butoxycarbonyl)piperazine (N-Boc-piperazine, NBPZ), deprotection of the Boc group with HCl, and dithiocarbamation with carbon disulfide (CS2). By using the NBPZ reagent in the amination step, the self-cross-linking of piperazine (PZ) could be completely suppressed, unlike using the PZ reagent. Consequently, the PZ-DTC group density of the fibrous grafted metal adsorbent synthesized through NBPZ attained 2.122 mmol-PZ-DTC/g-adsorbent, which was approximately 6 times higher than that of the metal adsorbent synthesized through PZ. The fibrous grafted metal adsorbent with the PZ-DTC group selectively adsorbed heavy metal ions over light metal ions. Furthermore, it exhibited high adsorption capacity, particularly for Cu2+. The Cu2+ adsorption capacity was determined to be 1.903 mmol-Cu2+/g-adsorbent by a batchwise adsorption test using a single-metal-ion aqueous solution at pH 6. The order of metal ion selectivity of the fibrous grafted metal adsorbent with the PZ-DTC group was Na+ < Mg2+, Ca2+, Co2+, Cd2+ < Pb2+ ≪ Cu2+, and Co2+ ≈ Ni2+ < Zn2+ ≪ Cu2+. In addition, the fibrous grafted metal adsorbent with the PZ-DTC group did not lose its metal adsorption function even under highly alkaline conditions (pH 15). It could recover Cu2+ efficiently and selectively from a high-concentration Na+ aqueous solution at this pH. The Cu2+ adsorption capacity of the fibrous grafted metal adsorbent with the PZ-DTC group was 0.754 mmol-Cu2+/g-adsorbent under a highly alkaline condition, a 10 M NaOH aqueous solution at pH 15. This value was approximately 2.4 times higher than that of the other grafted adsorbent with an amine-type functional group.

Development of a Simplified Radiation-Induced Emulsion Graft Polymerization Method and Its Application to the Fabrication of a Heavy Metal Adsorbent.

A simplified radiation-induced emulsion graft polymerization (SREG) method is proposed. This method involves a convenient and easy degassing process of a monomer solution using a commercially available sealed glass jar. A loaded weight on the lid of the jar was used to control the jar's internal pressure as the degassing of the monomer solution took place using a vacuum pump. The degassing method was highly reproducible, resulting from no bumping of the monomer solution. The initial grafting velocity was proportional to the absorbed doses of pre-irradiation between 5 and 20 kGy. This result indicates that dissolved oxygen was sufficiently eliminated from the monomer solution at such a level where the remaining oxygen had little effect on the grafting reaction at a dose of 5 kGy. The method was then applied to the fabrication of a heavy metal adsorbent that possessed a sufficient adsorption capacity of Co(II) ions. The SREG method is applicable to the fabrication of a wide variety of functional graft polymers because high-dose-rate gamma-ray radiation and expensive experimental equipment are not necessary.

Surface Engineering of Fluoropolymer Films via the Attachment of Crown Ether Derivatives Based on the Combination of Radiation-Induced Graft Polymerization and the Kabachnik-Fields Reaction.

In this manuscript, we present the successful attachment of crown ether moieties onto fluoropolymer surfaces, via the combination of radiation-induced graft polymerization and a subsequent surface Kabachnik-Fields three-component reaction. The obtained crown ether-tethered fluoropolymer films exhibited an ammonium cation capturing ability, owing to the host-guest interactions (i.e., hydrogen bonding) between the surface-anchored crown ethers and the guest ammonium cations.

[A Clinical Study of a Mucosa-Associated Lymphoid Tissue (MALT) Lymphoma of Salivary Glands].

Malignant lymphoma involving the salivary glands is a rare entity that accounts for only 1 to 4% of all salivary gland tumors. We have analyzed the clinical features of MALT lymphoma of the salivary glands in 7 patients whom we have treated in the past 10 years, including data from 43 patients in the literature. The most common symptom was persistent or progressive swelling of the salivary glands without pain or facial palsy. The affected glands were the unilateral parotid in 62%, the unilateral submandibular gland in 6.8%, and the bilateral parotid or submandibular gland in 6.8%. The salivary gland swelling as evaluated by MRI or ultrasonography consisted of a localized solitary tumor in 68.9%, multiple tumors in 10.3%, and diffuse swelling of the gland in 26.1%. In 24 out of 50 patients, MALT lymphoma developed on the basis of Sjögren's syndrome. As for diagnosis, malignant lymphoma was suspected only in 4 cases out of 11 (36.7%) based on the fine needle aspiration cytology. In all patients, a definitive diagnosis was obtained based on histopathological study of the localized tumor or the biopsy specimens. When patients with Sjögren's syndrome have developed persistent swelling of the salivary glands, it is necessary to rule out malignant lymphomas, especially MALT lymphoma, by combination of ultrasonography, MRI, FNA, and biopsy or open surgery depending on image findings. The treatment of MALT lymphoma has not yet been standardized because MALT lymphoma is a rare entity. The choice of initial treatment is important because it is related to its prognosis. If MALT lymphoma remains in a local site, we should undertake an operation or radiotherapy. If MALT lymphoma has dissemineated systemically, we should choose chemotherapy.

[A Clinical Study of the Sclerotherapy for Large Venous Malformations of the Pharyngolarynx with Airway Stenosis].

We treated four cases of airway stenosis associated with large venous malformations of the pharyngolarynx. The patients ranged in age from 33 to 53 years, and consisted of one male and three females. The venous malformation was located in the posterior wall of the oropharynx in two cases, in the hypopharynx in. one case, and in the anterior wall of the oropharynx in one case. All the patients complained of shortness of breath upon adopting the supine position. The patients were tracheotomized under general anesthesia and treated by sclerotherapy under videolaryngoscopic guidance. We used absolute ethanol, polidocanol or monoethanolamine oleate, as appropriate, depending on the case. In regard to the efficacy of the sclerotherapy, the venous malformation disappeared in one case and reduced in size in the remaining three cases, and no severe adverse events were recognized in any of the cases. All the patients were discharged from the hospital within two weeks and did not need tracheostomy. Sclerotherapy umder videolaryngoscopic guidance is effective for the treatment of large venous malformations in the pharyngolarynx.

[The efficacy of superselective intra-arterial chemo-radiotherapy for cervical neck lymph node metastases].

We report herein on 32 cases of head and neck carcinoma with cervical lymph node metastases treated by radiotherapy and concomitant intraarterial cisplatin (RADPLAT) from April 2009 to May 2013. N3 cases revealed residual disease of the cervical lymph nodes in 7/9 cases. Among the 22 patients excluding N1 and N3 cases, the pathological CR rate was 63.6%. Among the 13 patients in whom the anticancer drug was directly infused into the cervical lymph nodes, the pathological CR rate was 76.9%, whereas in the 9 patients without direct infusion of the cervical lymph nodes, the pathological CR rate was 44.4%. Therefore, we recommend the direct infusion into cervical lymph node metastases for not only N3 cases but also N2 cases if a feeding artery is identified easily. When clinical examination after RADPLAT leads to suspected residual disease, neck dissection should be adapted. If the clinical examination leads to a diagnosis of CR, we recommend a biopsy of the original cervical lymph nodes because the cases which we diagnosed as CR revealed residual disease of the cervical lymph nodes in 4/16.

[Four cases of extracranial trigeminal benign neurogenic tumors].

Extracranial trigeminal schwannomas are rare tumors accounting for about 10% of all trigeminal schwannomas. We report herein on four cases of extracranial trigeminal benign neurogenic tumors. The patients were aged between 39 and 75 years; they consisted of one male and three females. The origins of the schwannomas consisted of the maxillary nerve in two cases and the mandibular nerve in two cases. All cases were surgically treated using a transmaxillary approach in three cases, and a combination of the transcervical-parotid approach with a midline mandibulotomy in one case. In two cases, the schwannomas located in the pterygopalatine fossa were removed using a transmaxillary approach with the endoscope and the surgical microscope. Two patients underwent selective intravascular embolization of the feeding artery to reduce intraoperative bleeding, and they were less invasively treated via the transmaxillary approach.

[A clinical study on 8 cases of sarcoidosis with a cervical mass as a symptom].

Sarcoidosis is a multiorgan granulomatous disease of unknown origin, which frequently involves the lung and the eyes. It is rare that sarcoidosis causes cervical lymphadenopathy and a chronic continuous salivary gland swelling. In the present study, we examined how to diagnose sarcoidosis in patients complaining of a cervical mass and its clinical presentation according to 8 cases which we experienced. We undertook biopsy of the cervical lymph nodes in 7 cases, and biopsy of the parotid gland in 1 case. In cases non-caseating epithelioid cell granuloma was proved, diagnosed as sarcoidosis histopathlogically. In 6 patients, the sarcoidal lesion was in other organs, whereas in 2 patients the sarcoidal lesion was confined in the head and neck. Bilateral hilar lymphadenopathy and an elevated level of angiotensin-converting enzyme which are typical in sarcoidosis were confirmed in only one of our patients. Therefore, the diagnostic value of these tests is low for the diagnosis of sarcoidosis in the patients whose chief complaint is a cervical mass. Because 4 out of 7 cases were positive for the tuberculin test, it is imperative to distinguish between sarcoidosis and cervical tuberculous lymphadenitis by combining the culture of acid-bacilli and TB-PCR with histopathological evaluation of the biopsy specimen. We experienced one patient in whom the sarcoidal lesion developed in the skin and the eyes 20 years after the onset of cervical lymphadenopathy. It is important to follow the patients carefully, even if we diagnose the disease as sarcoidosis confined in the head and neck.

[A clinical study on 10 cases of cervical tuberculous lymphadenitis].

Cervical tuberculous lymphadenitis is sometimes difficult to differentiate from sarcoidosis. We treated 10 patients with cervical tuberculous lymphadenitis from April 2002 to December 2011. Their ages ranged from 42 to 78 years old (mean 63.2 years), and the male-to-female ratio was 4: 6. All patients presented to our hospital with the chief complaint of a cervical mass. All patients underwent open biopsy of the cervical lymph nodes, and 8 patients were diagnosed histopathologically as having cervical tuberculous lymphadenitis. In the remaining 2 patients, caseous necrosis could not be recognized histopathologically and they were diagnosed as having sarcoidosis. However 8 weeks later, the culture of the acid-fast bacilli turned positive, and the diagnosis was corrected to cervical tuberculous lymphadenitis. In our cases, the culture of acid-fast bacilli was positive in 6 out of 9 cases (66.7%), and TB-PCR was positive in 4 out of 9 cases (44.4%). These results show that sensitivity of individual tests is rather low. For the diagnosis of cervical tuberculous lymphadenitis, it is important to suspect this disease from the findings of the sedimentation rate, tuberculin test, and ultrasonography with fine needle aspiration cytology. On performing an open biopsy of the cervical lymph nodes in the suspected patients, it is essential to combine histopathological study, TB-PCR and the culture of the acid-fast bacilli simultaneously.

[Two cases of spontaneous cerebrospinal fluid (CSF) otorrhea with meningitis].

We report on two cases of spontaneous CSF otorrhea, which were considered to have been caused by enlarged arachnoid granulation with bone erosion of the posterior fossa. Both cases visited us complaining of severe headache, due to bacterial meningitis. In the first patient, a 68-year-old male, a high resolution CT scan showed a bony defect in the posterior fossa plate in the right temporal bone, where CSF leakage was confirmed during the operation. In the second patient, a 54-year-old female, a bony defect was located in the posterior fossa in the left temporal bone. In both cases, the bony defects were repaired by occlusion with the pedicled temporal muscles after the meningitis had been treated. CSF otorrhea disappeared after the surgery, and has not recurred during the postoperative observation period of 1 to 3 years.

Tailoring elution of tetraalkylammonium ions. Ideal electrostatic selectivity elution order on a polymeric ion exchanger.

Although ion exchange is often depicted as a process driven by electrostatic forces, ionic solvation or hydrophobic forces contribute greatly to ion exchange selectivity and is often the dominant factor. On a variety of commercial anion exchange columns, monovalent ClO4- elutes after doubly charged SO42- and even triply charged PO43-. For identically charged alkali metal ions, electrostatic charge densities based on crystal radii would suggest Li+ to be the most strongly retained on a cation exchanger. In practice, it is typically the least strongly held cation on most cation exchangers, because of its very high hydration energy and with most eluents its capacity factor approaches zero. Even when the ion is very poorly solvated, as with tetraalkylammonium (NR4+) cations, there has never been a report on a polymeric ion exchanger of an ideal electrostatic selectivity order where NR4+ cations elute in their increasing charge density order: R = n-butyl first, followed by n-propyl, ethyl, and last, methyl. We show that this selectivity order is easily achieved on recently described methracrylate-based monolithic capillary cation exchange columns (Ueki, Y.; Umemura, T.; Li, J. X.; Odake, T; Tsunoda, K. Anal. Chem. 2004, 76, 7007-7012) with minor amounts of hydroorganic modifiers. Indeed, under such conditions, Li+ (and other alkali cations) elutes after NMe4+.

Preparation and characterization of methacrylate-based semi-micro monoliths for high-throughput bioanalysis.

Hexyl methacrylate (HMA)-based monolithic semi-micro columns were prepared by in situ polymerization within the confines of 1.02-mm-i.d. silicosteel tubing for reversed-phase and/or precipitation-redissolution liquid chromatography. Practically useful monolithic columns with adequate separation efficiency, high permeability, and good mechanical strength were successfully obtained using a polymerization mixture comprising 24% hexyl methacrylate (HMA), 6% ethylene dimethacrylate (EDMA), 44.5% 1-propanol, and 25.5% 1,4-butanediol. The column performance was evaluated through the separations of a series of alkylbenzenes. At a normal flow rate of 50 microL min(-1), the produced HMA-based monolithic columns typically exhibited 3,000 theoretical plates for a 20-cm-long column, and the pressure drop was generally less than 1 MPa per 20 cm. The monolithic columns were resistant to at least 15 MPa, and could be properly operated at 15-20 times higher flow rate than normal, reducing the separation time to 1/15-1/20. The HMA-based monolithic columns were applied to rapid and efficient separations of proteins such as ribonuclease A, cytochrome c, transferrin, and ovalbumin in the precipitation-redissolution mode. Using a CH(3)CN gradient elution at a flow rate of 1,000 microL min(-1), four proteins were baseline separated within 20 s.

Preparation of low flow-resistant methacrylate-based monolithic stationary phases of different hydrophobicity and the application to rapid reversed-phase liquid chromatographic separation of alkylbenzenes at high flow rate and elevated temperature.

Low flow-resistant alkyl methacrylate-based monolithic stationary phases of different hydrophobicity were constructed for reversed-phase capillary liquid chromatography by thermally initiated radical polymerization of respective methacrylate ester monomer with different alkyl chain (C2, C4, C6, C12, C18) and ethylene glycol dimethacrylate (EDMA) in a 250 microm i.d. fused silica capillary. The hydrophobicity was basically controlled by changing the length and/or the density of the alkyl-chain, while the composition and the ratio of porogenic solvent were adjusted to obtain highly permeable rigid monoliths with adequate column efficiency. Among the prepared monolithic stationary phases, C18-methacrylate monoliths polymerized from a binary porogenic solvent of isoamyl alcohol and 1,4-buthandiol exhibited the most promising performance in terms of hydraulic resistance and column efficiency. The pressure drops of 20-cm long monolithic columns were below approximately 0.4 MPa at a normal linear velocity of 1mm/s (a flow rate of 3 microL/min), and the numbers of theoretical plates for alkylbenzenes mostly exceeded 3000 plates/20 cm. The produced monolithic columns had good mechanical strength for high pressure and temperature, and could be properly operated even at a temperature of 80 degrees C and at a pressure of at least 33 MPa. At 80 degrees C, the theoretical plate numbers reached 6000 plates/20 cm because of the enhanced mass transfer. Due to the novel hydraulic resistance and mechanical strength, the separation time could be reduced 120-fold simply by raising the flow rate and column temperature.

Evaluation of an ODS column modified with zwitterionic/nonionic mixed surfactants and its application to direct injection determination of inorganic anions.

An octadecylsilica (ODS) column modified with zwitterionic/nonionic mixed surfactants was evaluated for the direct injection determination of inorganic anions in biological fluids by ion chromatography. A zwitterionic surfactant (sulfobetaine-type) and a nonionic surfactant (polyoxyethylene-type) were used for a stationary-phase modification. When aqueous electrolyte solutions with concentrations of sub-mM to several mM were used as a mobile phase, the zwitterionic surfactant coated on the ODS surface exhibited unique separation selectivity for ionic species, while the nonionic surfactant coated on the ODS might have formed a hydrophilic network over the ODS surface and restricted matrix proteins from adsorbing on the stationary phase. Consequently, the mixed surfactant-modified column system allowed an efficient ion chromatographic separation of inorganic anions as well as a size-exclusive removal of column-fouling proteins. This separation system was applied to the direct injection determination of UV-absorbing anions in human saliva. The detection limits for nitrite, nitrate, iodide and thiocyanate were 3.1, 2.7, 4.5 and 25 microM, respectively, with UV detection at 210 nm (injection volume; 20 microl), and their relative standard deviations for 5 replicate measurements of saliva samples spiked with 100 microM each of those anions were 1.4, 0.9, 2.2 and 5.5%, respectively.

Preparation and application of methacrylate-based cation-exchange monolithic columns for capillary ion chromatography.

Polymer-based strong cation-exchange monolithic capillary columns with different capacities were constructed for ion chromatography by radical polymerization of glycidyl methacrylate (GMA) and ethylene dimethacrylate in a 250-microm-i.d. fused-silica capillary and its subsequent sulfonation based on ring opening of epoxides with 1 M Na(2)SO(3). The cation-exchange capacities can easily and reproducibly be controlled in the range of up to 300 microequiv/mL by changing the immersion time of the epoxy-containing polymer in the Na(2)SO(3) solution. The chromatographic performance of the produced monolithic capillary columns was evaluated through the separation of a model mixture of common cations such as Na(+), NH(4)(+), K(+), Mg(2+), and Ca(2+). As an example, these cations could be well separated from one another on a 15-cm-long cation-exchange monolithic column (column volume, 7.4 microL) with a capacity of 150 microequiv/mL by elution with 10 mM CuSO(4). The pressure drop of this 15-cm column was approximately 1 MPa at a normal linear velocity of 1 mm/s (a flow rate of 3 microL/min), and the numbers of theoretical plates for the cations were above 3000 plates/15 cm. This GMA-based cation-exchange monolithic column could withstand high linear velocities of at least 10 mm/s. Over a period of at least two weeks of continuous use, no significant changes in the selectivity and resolution were observed. The applicability of a flow rate gradient elution and the feasibility of direct injection determination of major cations in human saliva sample were also presented.