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Vacuum residue (VR) was copyrolysed with polyethylene (PE) or polystyrene (PS) in a batch reactor to investigate the corresponding synergistic pyrolytic interactions. The synergistic interactions between VR and plastic pyrolysates enhanced liquid and gas production while reducing coke formation, as compared with VR-only and plastic-only pyrolysis. The pyrolysis of 9:1 w/w VR: PE 3M (PE with M w = 3 MDa) and 9:1 w/w VR/PS 350K (PS with M w ≈ 350 kDa) mixtures produced oil in yields of 28.6 and 38.4 wt%, respectively, which exceeded those expected in the absence of synergistic interactions 1.12- and 1.29-fold, respectively. The corresponding coke yields were ~ 0.9 times lower than those expected in the absence of synergistic interactions. Moreover, copyrolysis synergistically increased the yields of oil-phase paraffins and olefins while decreasing that of aromatic compounds and was therefore concluded to enable effective VR utilisation and plastic recycling by enhancing liquid and gas production., (© 2024. The Author(s).)

Nanocatalysts tend to aggregate and are difficult to recycle, limiting their practical applications. In this study, an environmentally friendly method was developed to produce cellulose beads for use as supporting materials for Cu-based nanocatalysts. Cellulose beads were synthesized from a water-in-oil emulsion using cellulose dissolved in an LiBr solution as the water phase and vegetable oil as the oil phase. Upon cooling, the gelation of the cellulose solution produced spherical cellulose beads, which were then oxidized to introduce surface carboxyl groups. These beads (diameter: 95-105 μm; specific surface area: 165-225 m 2  g -1 ) have a three-dimensional network of nanofibers (width: 20-30 nm). Furthermore, the Cu 2 O nanoparticles were loaded onto oxidized cellulose beads before testing their catalytic activity in the reduction of 4-nitrophenol using NaBH 4 . The apparent reaction rate constant increased with increasing loading of Cu 2 O nanoparticles and the conversion efficiency was >90 %. The turnover frequency was 376.2 h -1 for the oxidized cellulose beads with the lowest Cu 2 O loading, indicating a higher catalytic activity compared to those of other Cu-based nanoparticle-loaded materials. In addition to their high catalytic activity, the cellulose beads are reusable and exhibit excellent stability., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The solubilities of many substances are significantly affected by specific ions, as demonstrated by the Hofmeister series of proteins. Cellulose has a resistant fibrillar structure that hinders its swelling and dissolution. Certain inorganic salt solutions are effective swelling agents and solvents for cellulose. However, the precise effects of these ions on cellulose are not fully understood. In this study, we studied the intermediate structures of cellulose fibers during their swelling process in ZnCl 2 and LiBr solutions via in situ X-ray diffraction. Two swollen phases with characteristic morphologies were observed for both salt treatments. Only the surfaces of the fibers were swollen in ZnCl 2 , whereas the ions penetrated the fibers and formed complexes with cellulose while the morphology of the fibers was maintained in LiBr. Our findings clarify the reasons that ZnCl 2 has been used as an excellent swelling agent, whereas LiBr has been used as a good solvent for cellulose.

We demonstrated that a unique polysaccharide with extremely high molecular weight can be easily obtained via a low-cost, mild reaction in a water medium from sucrose, a photosynthetic product. α-1,3/1,6-Glucosyltransferase L (GtfL) from Streptococcus salivarius produced water-insoluble α-d-glucan from sucrose at 37 °C. Gel permeation chromatography revealed the molecular weight was extremely high; the weight-average molecular weight values were more than 1,000,000 irrespective of the substrate concentration. The Smith degradation of neat glucan and NMR spectroscopic analyses of the acetyl derivative revealed a structure similar to that of a comb-type graft copolymer, α-d-(1 → 3)-graft-(1 → 6)-glucan. The anhydroglucose units (AGUs) in the main-chain backbone are linked by (1 → 3)-glycosidic bonds, whereas a side chain consisting of four AGUs via (1 → 6)-glycosidic bonds alternately extends from C6 of the main chain., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

We explore dynamic nuclear polarization using electron spins in the photo-excited triplet state (Triplet-DNP) in magnetically oriented microcrystal arrays (MOMAs) of pentacene-doped p-terphenyl, in which the individual crystallites are magnetically aligned and UV-cured. In contrast to the conventional approach to Triplet-DNP in powder, which suffers from reduced nuclear polarization due to the averaged electron polarization and the broadening of electron-spin resonance, Triplet-DNP of the MOMAs offers as high dynamic polarization as that attainable in single-crystals. In the case of pentacene-doped p-terphenyl, the enhanced 1 H polarization in the one-dimensional MOMA, prepared simply by leaving the suspension in a stationary magnetic field before UV curation, can be higher than that attainable in the powder sample by an order of magnitude and comparable to that in single crystals and in the three-dimensional MOMA made using a modulational rotating field. Triplet-DNP of the MOMAs may find potential applications, such as the polarization of the co-doped target molecules and dissolution experiments., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Bioengineering approaches to modify lignin content and structure in plant cell walls have shown promise for facilitating biochemical conversions of lignocellulosic biomass into valuable chemicals. Despite numerous research efforts, however, the effect of altered lignin chemistry on the supramolecular assembly of lignocellulose and consequently its deconstruction in lignin-modified transgenic and mutant plants is not fully understood. In this study, we aimed to close this gap by analyzing lignin-modified rice (Oryza sativa L.) mutants deficient in 5-HYDROXYCONIFERALDEHYDE O-METHYLTRANSFERASE (CAldOMT) and CINNAMYL ALCOHOL DEHYDROGENASE (CAD). A set of rice mutants harboring knockout mutations in either or both OsCAldOMT1 and OsCAD2 was generated in part by genome editing and subjected to comparative cell wall chemical and supramolecular structure analyses. In line with the proposed functions of CAldOMT and CAD in grass lignin biosynthesis, OsCAldOMT1-deficient mutant lines produced altered lignins depleted of syringyl and tricin units and incorporating noncanonical 5-hydroxyguaiacyl units, whereas OsCAD2-deficient mutant lines produced lignins incorporating noncanonical hydroxycinnamaldehyde-derived units. All tested OsCAldOMT1- and OsCAD2-deficient mutants, especially OsCAldOMT1-deficient lines, displayed enhanced cell wall saccharification efficiency. Solid-state nuclear magnetic resonance (NMR) and X-ray diffraction analyses of rice cell walls revealed that both OsCAldOMT1- and OsCAD2 deficiencies contributed to the disruptions of the cellulose crystalline network. Further, OsCAldOMT1 deficiency contributed to the increase of the cellulose molecular mobility more prominently than OsCAD2 deficiency, resulting in apparently more loosened lignocellulose molecular assembly. Such alterations in cell wall chemical and supramolecular structures may in part account for the variations of saccharification performance of the OsCAldOMT1- and OsCAD2-deficient rice mutants., (© American Society of Plant Biologists 2022. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Although the measurement of hemoglobin A1c (HbA1c) using high-performance liquid chromatography (HPLC) is routinely used to estimate average blood glucose levels, it may not be accurately measured for various reasons, such as alteration of red blood cell lifespan and the existence of hemoglobin variants; including hemoglobin F (HbF). Here, we report cases of fulminant type 1 and type 2 diabetes mellitus in which HbA1c levels were unmeasurable because of increased labile HbA1c levels. Case 1 involved a 73-year-old man with fulminant type 1 diabetes mellitus, who was brought to our hospital with diabetic ketoacidosis. The patient's blood glucose level was 994 mg/dL, and HbA1c was unmeasurable, which turned out to be 6.2% on the next day when the blood glucose level was normalized. Case 2 involved a 72-year-old man with type 2 diabetes mellitus, whose blood glucose level was 767 mg/dL, and HbA1c was unmeasurable, which turned out to be 17.9% the following day. In both cases, the chromatograms showed that the HbA1c peaks overlapped with large labile HbA1c peaks, which decreased the next day. It is important to keep in mind that HbA1c levels may not be accurately measured in cases of extreme hyperglycemia because of an increase in labile HbA1c, regardless of the absolute HbA1c level., Competing Interests: Conflict of interestThe authors declare that there is no conflict of interest., (© The Japan Diabetes Society 2022.)

The cystine/glutamate antiporter, system x c - , is essential for the efficient uptake of cystine into cells. Interest in the mechanisms of system x c - function soared with the recognition that system x c - presents the most upstream node of ferroptosis, a recently described form of regulated necrosis relevant for degenerative diseases and cancer. Since targeting system x c - hold the great potential to efficiently combat tumor growth and metastasis of certain tumors, we disrupted the substrate-specific subunit of system x c - , xCT (SLC7A11) in the highly metastatic mouse B16F10 melanoma cell line and assessed the impact on tumor growth and metastasis. Subcutaneous injection of tumor cells into the syngeneic B16F10 mouse melanoma model uncovered a marked decrease in the tumor-forming ability and growth of KO cells compared to control cell lines. Strikingly, the metastatic potential of KO cells was markedly reduced as shown in several in vivo models of experimental and spontaneous metastasis. Accordingly, survival rates of KO tumor-bearing mice were significantly prolonged in contrast to those transplanted with control cells. Analyzing the in vitro ability of KO and control B16F10 cells in terms of endothelial cell adhesion and spheroid formation revealed that xCT expression indeed plays an important role during metastasis. Hence, system x c - emerges to be essential for tumor metastasis in mice, thus qualifying as a highly attractive anticancer drug target, particularly in light of its dispensable role for normal life in mice., (© 2020 Union for International Cancer Control.)

A hydrogel was prepared from a polysaccharide, enzymatically synthesized through a one-pot reaction in aqueous solution, and its properties as a functional material were evaluated. Enzymatic synthesis using glucosyltransferase K obtained from Streptococcus salivarius ATCC 25975 was performed with sucrose as a substrate. The synthetic product was unbranched linear (1 → 6)-α-d-glucan with a high molecular weight, M w : 1.0-3.0 × 10 5 . The synthesized (1 → 6)-α-d-glucan was insoluble in water and crystallized in a monoclinic unit cell, which is consistent with the hydrated form of dextran. Transparent and highly swellable (1 → 6)-α-d-glucan hydrogels were obtained by crosslinking with diglycidyl ethers. The hydrogels showed no syneresis and no volume change during compression, resulting in the retention of shape under repeated compression. The elastic moduli of these hydrogels (<60 kPa) are smaller than those of other polysaccharide-based hydrogels having the same solid contents. The oven-dried gels could be restored to the hydrogel state with the original transparency and a recovery ratio greater than 98%. The mechanism of water diffusion into the hydrogel was investigated using the kinetic equation of Peppas. The properties of the hydrogel are impressive relative to those of other polysaccharide-based hydrogels, suggesting its potential as a functional biomaterial., Competing Interests: The authors declare no competing financial interest., (© 2020 The Authors. Published by American Chemical Society.)

Cationic hydrogels with amino groups were successfully prepared using (1→3)-α-d-glucan synthesized by glucosyltransferase J (GtfJ) cloned from Streptococcus salivarius through a three-step reaction: (i) Azido groups were regioselectively introduced at the C6 position of (1→3)-α-d-glucan by a bromination-azidation process (degree of substitution 0.94), (ii) Azido groups were partially crosslinked with 1,8-nonadiyne via a copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC) reaction, (iii) Azido groups that were unused for crosslinking were reduced to amino groups by sodium borohydride (NaBH 4 ). The introduction of amino groups was confirmed quantitatively and qualitatively by elemental, Fourier transform infrared (FT-IR), and nuclear magnetic resonance (NMR) analyses. These cationic hydrogels showed a specific adsorption ability for bovine serum albumin (BSA) over a wide pH range of 4.5-8.0 due to their high pH values at the point of zero charge (pH pzc 8.80-8.92)., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

We examined typical commercial poly(ethersulfone) (PESf) hemodialysis and hemoconcentration membranes successfully used in manufacturing, and employed scanning probe microscope (SPM) to achieve a structural observation of the pores in the inner membrane surfaces, as well as measure the pore diameters and their distribution, verifying the relationship between the typical mass transfer properties. We focused on the differences between the PESf membranes which were expected to further improve the advanced pore structure control and functional design for various medical uses. The three-dimensional tortuous capillary pores on the inner surface of hollow fiber hemodialysis and hemoconcentrator membranes were investigated using dynamic force microscopy (DFM), and the pore diameter and distribution were measured through a line analysis. Compared with PUREMA-A, PES-Sα hemodialysis membranes have smaller three-dimensional tortuous capillary pore diameters and pore areas, as well as a smaller pore diameter distribution and pore area distribution, which make the accurate measurements of the pore diameter using FE-SEM impossible. These PESf membranes are almost the same in pure water permeability, but greatly differ in pore diameter and pore diameter distribution. By comparing and verifying as above, we may gain insight into the flexibility, versatility, and superior structural and functional controllability of PESf membrane pore structures, which could advance the development of pore structure control. Pending issues include the fact that, using a line analysis software of SPM devices, it is very difficult to measure hundred pores which clearly reflects the poor quality of pore size distributions obtained in this study, measurement accuracy must be improved further.

(1→3)-α-d-glucan synthesized by glucosyltransferase J (GtfJ) cloned from Streptococcus salivarius was regioselectively aminated as 6-amino-6-deoxy-(1→3)-α-d-glucan (aminoglucan) through three steps: bromination, azidation, and reduction. The degree of substitution of the amino group was determined by elemental analysis to be 0.97 and the molecular weight was 3.74×10 4 as measured by size exclusion chromatography. The regioselective amination at the C6 position of every pyranose ring was confirmed by 1 H/ 13 C NMR and solid state 15 N cross polarization/magic angle spinning NMR spectroscopy. Aminoglucan was characterized by FT-IR, X-ray diffraction and thermogravimetric analysis. Solubility of aminoglucan in various solvents was investigated and confirmed in aqueous solution at pH ≤ 11. Therefore, aminoglucan was crosslinked with ethylene glycol diglycidyl ether (EGDE) by an epoxy-ring opening reaction under alkaline conditions. The obtained EGDE-crosslinked aminoglucan hydrogels were highly swellable in water owing to a strong water-holding ability and no water was released on compression and breaking of the gels., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

In situ solid-state NMR measurements of a magnetically oriented microcrystal suspension (MOMS) were demonstrated. Under modulated rotation of the static field, or equivalently, of the sample tube, randomly oriented microcrystals in a viscous liquid medium feel a torque arising from the anisotropic bulk susceptibility and eventually aligned in the same direction. In this way, a three-dimensional MOMS (3D-MOMS) was obtained. To apply an elliptically rotating magnetic field to microcrystals in suspension, a probe to rotate the sample tube around an axis perpendicular to the static magnetic field was developed. Single-crystal (SC) rotation patterns were obtained from the 3D-MOMS by solid-state CP measurements triggered in synchronous with the sample-tube rotation. Unlike the traditional SC method, the 3D-MOMS approach presented here does not require the elaborate adjustment of the direction of the reference frame. The process of three-dimensional magnetic alignment was also studied by monitoring the spectral changes during continuous application of the modulated sample rotation., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Lignin is a complex phenylpropanoid polymer deposited in plant cell walls. Lignin has long been recognized as an important limiting factor for the polysaccharide-oriented biomass utilizations. To mitigate lignin-associated biomass recalcitrance, numerous mutants and transgenic plants that produce lignocellulose with reduced lignin contents and/or lignins with altered chemical structures have been produced and characterised. However, it is not fully understood how altered lignin chemistry affects the supramolecular structure of lignocellulose, and consequently, its utilization properties. Herein, we conducted comprehensive chemical and supramolecular structural analyses of lignocellulose produced by a rice cad2 mutant deficient in CINNAMYL ALCOHOL DEHYDROGENASE (CAD), which encodes a key enzyme in lignin biosynthesis. By using a solution-state two-dimensional NMR approach and complementary chemical methods, we elucidated the structural details of the altered lignins enriched with unusual hydroxycinnamaldehyde-derived substructures produced by the cad2 mutant. In parallel, polysaccharide assembly and the molecular mobility of lignocellulose were investigated by solid-state 13 C MAS NMR, nuclear magnetic relaxation, X-ray diffraction, and Simon's staining analyses. Possible links between CAD-associated lignin modifications (in terms of total content and chemical structures) and changes to the lignocellulose supramolecular structure are discussed in the context of the improved biomass saccharification efficiency of the cad2 rice mutant.

The amino acid transport system x c - is important for maintaining intracellular glutathione levels and extracellular redox balance. The main component of system x c - , xCT, is strongly induced by various stimuli, including oxidative stress and bacterial lipopolysaccharides (LPS) in macrophages. In the present study, we investigated the production of nitric oxide by LPS-stimulated mouse peritoneal macrophages isolated from both xCT-deficient and wild-type mice. After culturing macrophages in the presence of LPS for 24-48 h, nitrite levels in the medium of xCT-deficient macrophages were significantly decreased compared to that of wild-type cells. However, the transport activity of arginine, a precursor of nitric oxide, and the expression of nitric oxide synthase 2 in xCT-deficient macrophages were similar to those of wild-type cells. When wild-type macrophages were cultured in the medium that contained no cystine, nitric oxide production was decreased to the level similar to that of the xCT-deficient macrophages. When xCT-deficient macrophages were cultured with 2-mercaptoethanol, intracellular cysteine levels were increased and nitrite accumulation in the medium was significantly increased. On the other hand, when these cells were cultured with buthionine sulfoximine, an inhibitor of glutathione synthesis, nitrite accumulation in the medium was essentially unchanged, although intracellular glutathione levels were very low. Reactive oxygen species levels in xCT-deficient macrophages were higher than those of wild-type cells, and treatment with LPS caused an increase in oxidative stress in both cells. These results suggest that intracellular cysteine supplied by xCT contributes to nitric oxide production and the reduction of oxidative stress in macrophages., (Copyright © 2018 Elsevier Inc. All rights reserved.)

The orientation of poly(l-lactic acid) (PLLA) crystals was controlled through crystal growth from a magnetically oriented nucleating agent, phenylphosphonic acid zinc (PPAZn). The one-dimensional magnetically oriented microcrystal array of PPAZn microcrystals revealed the relationship between the magnetization and crystallographic axes in the PPAZn crystal. The PPAZn microcrystals were homogeneously dispersed in PLLA via melt mixing, which decreased the molecular weight of the PLLA component due to degradation. The PPAZn microcrystals in the molten PLLA were uniaxially aligned under an 8-T static or rotating magnetic field. The wide-angle X-ray diffraction and small-angle X-ray scattering patterns of the PPAZn/PLLA composite films crystallized under each magnetic field showed that the PLLA lamellae grew from the surface of the PPAZn microcrystals, which were uniaxially oriented along the easy- or hard-magnetization axis, with the c -axis of PLLA parallel to the bc -plane of PPAZn. It was also suggested that the greater nucleating effect of PPAZn on PLLA was derived not from geometrical matching, but from factors such as favorable interactions and/or the plate-like shape of the microcrystal.

System x c - was recently described as the most upstream node in a novel form of regulated necrotic cell death, called ferroptosis. In this context, the small molecule erastin was reported to target and inhibit system x c - , leading to cysteine starvation, glutathione depletion and consequently ferroptotic cell death. Although the inhibitory effect of erastin towards system x c - is well-documented, nothing is known about its mechanism of action. Therefore, we sought to interrogate in more detail the underlying mechanism of erastin's pro-ferroptotic effects. When comparing with some well-known inhibitors of system x c - , erastin was the most efficient inhibitor acting at low micromolar concentrations. Notably, only a very short exposure of cells with low erastin concentrations was sufficient to cause a strong and persistent inhibition of system x c - , causing glutathione depletion. These inhibitory effects towards system x c - did not involve cysteine modifications of the transporter. More importantly, short exposure of tumor cells with erastin strongly potentiated the cytotoxic effects of cisplatin to efficiently eradicate tumor cells. Hence, our data suggests that only a very short pre-treatment of erastin suffices to synergize with cisplatin to efficiently induce cancer cell death, findings that might guide us in the design of novel cancer treatment paradigms.

We investigated the crystal structure and molecular arrangement of the linear (1→3)-α-d-glucan synthesized by glucosyltransferase GtfJ cloned from Streptococcus salivarius using sucrose as a substrate. The synthetic products had two morphologies: wavy fibril-like crystals as major and thin lamellae as minor products. Their structures were analyzed using electron microdiffraction, synchrotron X-ray powder diffraction, and solid-state 13 C NMR spectroscopy. The fibrils and lamellae had the same allomorphic form but different molecular arrangements. The wet crystals were in a hydrated form, which converted into an anhydrous form with a significant decrease in crystallinity on drying. The hydrated and anhydrous forms had an extended-chain conformation with 2/1 helix, and the hydrated form was estimated to contain one water molecule per glucose residue. The long glucan chains were folded in the fibril crystals, while the short, extended chains were arranged perpendicular to the base plane of the lamellae., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

The single-crystal rotation technique was applied to magnetically oriented microcrystal arrays (MOMAs) of cellobiose (monoclinic) to determine the principal values and principal axes of the chemical shift tensors of C1 and C1' carbons. Rotations were performed about the magnetic χ1, χ2, and χ3 axes of MOMA, and the measurements were taken at six different orientations with respect to the applied magnetic field. Under these rotations, crowded peaks were reduced and the peaks for the C1 and C1' carbons were identified by comparing with simulation results. Six components of the chemical shift tensor expressed with respect to the magnetic χ1χ2χ3-frame were determined. The tensors thus obtained were transformed into those relative to the molecular frame., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Chemical shift tensors for the carboxyl and methyl carbons of L-alanine crystals were determined using a magnetically oriented microcrystal array (MOMA) prepared from a microcrystalline powder sample of L-alanine. A MOMA is a single-crystal-like composite in which microcrystals are aligned three-dimensionally in a matrix resin. The single-crystal rotation method was applied to the MOMA to determine the principal values and axes of the chemical shift tensors. The result showed good agreement with the literature data for the single crystal of L-alanine. This demonstrates that the present technique is a powerful tool for determining the chemical shift tensor of a crystal from a microcrystal powder sample., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Microphthalmia-associated transcription factor (Mitf) is a regulator for differentiation of melanoblasts that are derived from the neural crest. The mouse homozygous for the black-eyed white (Mitf(mi-bw)) allele is characterized by the white coat color and deafness, with black eye that is associated with the lack of melanocytes in skin and inner ear. The Mitf(mi-bw) mutation is an insertion of the LINE1 retrotransposable element into intron 3 of the Mitf gene that causes the selective deficiency of the melanocyte-specific Mitf isoform, Mitf-M. Here, we show the expression of Mitf-M mRNA in the trunk region of the homozygous Mitf(mi-bw)(bw) mouse at embryonic days (E) 11.5 and E12.5, but Mitf-M mRNA is undetectable at E13.5. In addition, using bw mouse that carries the lacZ transgene under the control of a melanoblast-specific promoter, we show that the number of migrating melanoblasts in bw embryos was less than 10% of that in control embryos at E11.5 and E12.5, and melanoblasts disappear by E13.5. The loss of melanoblasts in bw embryos was probably caused by apoptosis. Finally, forced expression of Mitf-M in the cultured neural tube of bw embryos ensured the differentiation of melanoblasts. Therefore, the correct dose of Mitf-M is required for the normal development of melanoblasts., (© 2012 The Authors. Journal compilation © 2012 by the Molecular Biology Society of Japan/Blackwell Publishing Ltd.)

Enzymatic hydrolysis was conducted with Pseudomonas lipase for film samples of graft copolymers of cellulose acetate (CA) and butyrate (CB) with poly(epsilon-caprolactone) (PCL), CA-g-PCL, and CB-g-PCL, respectively. The two trunk polymers CA and CB, both having the degree of acyl substitution (DS) of >2, are respectively immiscible and miscible with PCL. A hindrance effect of the cellulose ester trunks on the enzymatic attack to the PCL component was observed for the two copolymer series; the situation was more conspicuous in the use of CB trunks. After the selective hydrolytic degradation of the PCL component, a topographical study by AFM revealed that the CA and CB constituents as residues formed a protuberant structure on the surface of the respective film specimens. The altitude and regularity of the protuberances were variant depending on the initial copolymer composition. In a phase-imaging mode of AFM, a hydrolyzed film of CA-g-PCL with an extremely low graft-density (acetyl DS > 2.95) showed particularly larger CA domains of >25 nm in diameter. The domain sizes were in accordance with a heterogeneity scale in the original intercomponent mixing state estimated by (1)H spin-lattice relaxation time (T(1)(H)) measurements in solid-state (13)C NMR spectroscopy. The present results demonstrate a high potential in application of the PCL-grafted cellulosic copolymers as spatiotemporally biodegradation-controllable materials.

B -Catenin is closely associated with carcinoma invasion/metastasis and poor survival. Recent studies have demonstrated that abnormal expression of B -catenin, especially its nuclear accumulation, also plays an important role in wingless/Wnt signaling pathway. In this study, we evaluated immunohistochemically the nuclear localization of B -catenin in a total of 93 human-endocrine-related tumors including 1 medullary carcinoma (thyroid gland), 12 parathyroid tumors, 22 carcinoid tumors (digestive tract and liver), 7 islet cell tumors, 26 adrenocortical tumors, 13 neuroblastoma (adrenal gland), and 12 pheochromocytoma (adrenal gland), and also studied genetic alterations of the B -catenin gene. Nuclear accumulation of B -catenin was frequently detected in 8 of 22 (36%) carcinoid tumors and 2 of 7 (29%) islet cell tumors. No genetic alteration in exon 3 of the B -catenin gene encoding serine/threonine rich domain, which was phosphorylated by GSK-3 B, was detected in any groups of the endocrine tumors. However, nuclear accumulation of B -catenin in carcinoid tumors was significantly correlated with the proliferative marker Ki-67 (MIB-1) labeling index (p <0.001). Our findings suggest that nuclear transfer and accumulation of the B -catenin may contribute in the tumorigenesis of carcinoid tumor as an oncoprotein.

Air travel is convenient but can exacerbate underlying medical conditions. Most problems can be related to changes in atmospheric pressure, hypoxia, air sickness and jet lag. International travelers should be counseled about traveler's diarrhea and malaria if they are flying to endemic areas. Pregnancy is not in itself a contraindication to flying. Common-sense recommendations and reassurance can help assuage concerns about prolonged air travel.

A safe and simple method for obtaining cerebrospinal fluid from the anesthetized rabbit was accomplished by cannulating the fourth ventricle. Cerebrospinal fluid (1.5--2.0 ml) was obtained for laboratory analysis. The procedure could be repeated at 2--3 day intervals without detrimental effects.

The pharmacokinetics of spectinomycin hydrochloride after 2 g intravenous doses were studied in ten volunteers with varying degrees of renal function. Mean peak serum concentration in 8 volunteers with renal insufficiency was 150.9 +/- (SD) 42.3 microgram/ml which was similar to 2 normal volunteers who had concentrations of 139 and 186 microgram/ml. Serum half-lives in the volunteers with renal insufficiency ranged from 4.7 to 29.3 h and increased as creatinine clearance decreased. Serum half-lives of the 2 normal volunteers were 1.5 and 1.7 h. Urine concentrations and percents of recovery were variable.

Abnormal areas of increased uptake on liver scan have been controversial. While often said to be associated with superior vena caval obstruction, three distinctly different findings are possible: hot spot, warm spot, and no spot. All of these changes can be readily explained by distinct, separate anatomic venous collateral pathways. Four cases of superior vena caval obstruction with isotopic liver flow studies are presented. Anatomy of the venous collateral system is reviewed, and the potential significance of the liver "warm spot" is considered.

In 35 normal rabbits the cerebrospinal fluid glucose values ranged between 56 and 135 mg/dl, mean and standard deviation 78 +/- 13 mg/dl. Cerebrospinal total protein values ranged from 16 to 66 mg/dl, mean values were similar to those reported for human cerebrospinal fluid. Depression of the cerebrospinal glucose level in the rabbit may parallel the human situation and prove to be a useful marker of purulent inflammation.

Mezlocillin and carbenicillin were administered intravenously to healthy male volunteers, for six days each, in a double-blind crossover study. Tests to detect abnormalities in haemostasis were performed before, during and after administration. Platelet aggregation studies indicated that both antibiotics interfered with platelet aggregation and secretion resulting in prolonged bleeding times. The effect was dose related and rapidly reversible after discontinuation of the antibiotics. It always occurred earlier and was more profound with carbenicillin than with mezlocillin (P = 0.008). Bleeding times greater than 15 min were observed in 17% of volunteers who received 18 g/day of mezlocillin and 83% of volunteers who received 18 g/day of carbenicillin (P less than 0.05). There were no abnormalities in the coagulation cascade. The risk of acquiring an antibiotic-induced clinical bleeding disorder is lower with mezlocillin than with carbenicillin.