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Capability of the recycling of high strength and high fracture toughness yttria-stabilized tetragonal zirconia polycrystalline (Y-TZP) sintered body utilizing “low-temperature annealing degradation” phenomenon was investigated. Hydrothermal treatment was employed to induce the phase transformation from tetragonal to monoclinic zirconia and to disintegrate the Y-TZP sintered body. 3 mol% Y2O3–ZrO2 specimens sintered at 1,550 °C and more were disintegrated without leaving the original appearances when the treatment temperature was between 200 °C and 400 °C. The size of the disintegrated fragments of Y-TZP sintered body was much affected by hydrothermal treatment conditions. Only with hydrothermal treatment and simple ball milling, the sintered body was pulverized into the primary particle level. This technique is expected to apply to a sustainable recycling system for the zirconia ceramics, which restrains an energy consumption compared to crushing zirconia using mechanical procedures.

The recycling process for 3 mol% yttria-stabilized tetragonal zirconia polycrystals (3Y-TZP) sintered at 1450°–1550°C was examined by applying low-temperature degradation of zirconia ceramics under hydrothermal conditions. Hydrothermal treatment at a temperature from 200° to 240°C can lead to the spontaneous disintegration of 3Y-TZP sintered bodies into powdery particles. The hydrothermally obtained zirconia powder was found to consist of primary particles and aggregated particles. Detailed X-ray diffraction measurement revealed the formation of a cubic zirconia phase in the 3Y-TZP sintered bodies, which seemed to inhibit the disintegration of aggregated particles toward the primary particle level. The reclaimed 3Y-TZP powder was sintered again through a conventional powder processing route. The mechanical properties and microstructure of recycled 3Y-TZP sintered specimens were examined by comparison with those of the original 3Y-TZP sintered bodies. Dense recycled 3Y-TZP sintered at a higher temperature exhibited higher fracture toughness to some degree than the original 3Y-TZP.

A 65-year-old Japanese man was hospitalized because of acute hepatitis and severe cholestasis due to hepatitis E virus (HEV) infection combined with a drug reaction to a cold preparation. He died of disseminated intravascular coagulation and severe intestinal bleeding due to systemic cytomegalovirus reactivation following the development of severe eruptions with marked eosinophilia due to drug hypersensitivity to taurine and ursodeoxycholate preparations. The close interaction between viral infection or reactivation and drug hypersensitivity was considered as a pathophysiology in this case, which emphasizes the need for further study of the immunological mechanism of the interaction.

The following is a case study of a 36-year-old Japanese man with a trichoblastoma which exhibited a rippled-pattern on the left temporal region of the scalp. The histological findings of the tumor revealed lobular aggregations composed of immature follicular basaloid cells, lobules of squamous eddy-like foci of incomplete keratinization or small keratinous cysts, and multiple papillary mesenchymal bodies similar to hair germ. Interestingly, a rippled-pattern of basaloid cells and hyalinized matrixes resembling the Verocay bodies of neurilemmoma was also observed. We propose that the rippled-pattern of the basaloid cells and hyalinized matrices is caused by the characteristic stromal induction of trichoblastoma.

A 65-year-old Japanese man was hospitalized because of acute hepatitis and severe cholestasis due to hepatitis E virus (HEV) infection combined with a drug reaction to a cold preparation. He died of disseminated intravascular coagulation and severe intestinal bleeding due to systemic cytomegalovirus reactivation following the development of severe eruptions with marked eosinophilia due to drug hypersensitivity to taurine and ursodeoxycholate preparations. The close interaction between viral infection or reactivation and drug hypersensitivity was considered as a pathophysiology in this case, which emphasizes the need for further study of the immunological mechanism of the interaction.

Summary Background A simple list of diagnostic criteria for atopic dermatitis for use in epidemiological studies was developed by a U.K. working party. This list served well for both hospital patients with skin diseases and in general population within the U.K. Objectives To validate the U.K. diagnostic criteria in Japanese elementary schoolchildren, we collected the questionnaires on regular health checkups, which had been completed by parents of schoolchildren in 2001/2002 and 2004/2005. Methods Elementary schoolchildren were examined by dermatologists in eight areas (16,152 children) in 2001/2002 and in three areas (3849 children) in 2004/2005. The questionnaire was distributed to the parents 2 weeks before the skin examination, completed by the parents and collected after the survey. Results In 2002/2002 comparing the U.K. diagnostic criteria with the findings on clinical examination used as the reference standard, the U.K. criteria (1-year prevalence measure) showed a sensitivity of 71.8%, specificity of 89.3% and positive predictive value of 44.7%. In 2004/2005 we confirmed that the U.K. criteria for a point prevalence measure showed a higher positive predictive value (59.9%) compared with that for 1-year prevalence measure (49.3%). Conclusion Now that we know the sensitivity and specificity of the U.K. criteria in the population examined in this study, we will be able in the near future to estimate the prevalence of atopic dermatitis in a similar population with reverse operation by questionnaires alone using these criteria without examination by dermatologists. Therefore, the validation study of U.K. criteria could be useful for future epidemiologic surveys.

ejd.2012.1858 Auteur(s) : Chika Ohata1, Yasuki Mori2, Tomoko Tokita2, Hiroshi Koga1, Bungo Ohyama1, Ryosuke Sogame1, Takahiro Hamada1, Norito Ishii1, Minao Furumura1, Takashi Hashimoto1 hashimot@med.kurume-u.ac.jp 1 Department of Dermatology, Kurume University School of Medicine, 67 Asahimachi, Kurume, Fukuoka 830-0011, Japan 2 Department of Dermatology, Iwate Prefectural Central Hospital, Iwate, Japan Recently, we reported pemphigoid with autoantibodies to the laminin 332 γ2 subunit and BP230, [...]

We performed immunohistochemical, ultrastructural, terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling (TUNEL), and DNA ladder studies of apoptosis in nine cases of Merkel cell carcinoma (MCC). None of the cases showed spontaneous regression as has been reported in several MCCs. Neuron-specific enolase was demonstrated by immunohistochemistry (8/8 MCCs), and staining for cytokeratin 20 was positive (2/8 MCCs). Ultrastructural examination revealed many cytoplasmic dense-cored granules, desmosome-like structures, and intermediate filaments. The granules were seen along the plasma membrane or around perinuclear centrioles. We found various stages of development of apoptotic bodies. Apoptosis resulted in vacuolization and fragmentation of nuclei and phagocytosed bodies in tumor cells. Apoptotic cells were also detected by TUNEL, DNA ladder, and immunostaining using the antibody against Fas (Apo- 1/CD95) antigen. It seems that a high apoptotic rate is a common finding in MCC, although spontaneous regression is an exceedingly rare event. It is thus unlikely that apoptosis alone would explain spontaneous regression.

Double layered photoreceptors using low ionization potential molecules as the carrier transport layer (CTL) have been investigated. The ionization potential (l p ) was estimated by the ? technique calculation and the polarographic oxidation potential. A good correlation was obtained between the photosensitivity and the l p value of the CTL. However this result could not be explained simply by the energy level misfit of the carrier generation layer (CGL) and the CTL. Styryl dye bases, cyanine dye bases, and oxazoles were selected as CTL materials on the basis of their transparency and high solubility in polymers. The photoreceptors using these CTL materials showed much higher sensitivities than the well-known polyvinylcarbazole- trinitrofluorenone (PVK-TNF) system. The peak value of the spectral sensitivity in the system composed of an oxazole, OX-2, and a disazo pigment, chlorodianeblue (CDB), was 0.17 m 2/mJ at 650 nm.

3′-Deoxyseldomycin 5 (2), 2′-deamino-3′-epiamino-3′-deoxyseldomycin 5 (14), and 2′,3′-epimino-2′-deamino-3′-deoxyseldomycin 5 (15) were prepared from seldomycin 5 (1). Treatment of hexa-N-ethoxycarbonyl (ecb)-3′-O-tosylseldomycin 5 with sodium borohydride in DMSO gave the corresponding N-ecb-derivatives of 2, 14, and 15. Removal of the ecb groups of these compounds with aq potassium hydroxide gave the free bases 2, 14, and 15, respectively. Structure determination of the products was performed by means of MS, CMR, PMR, and chemical reactions. It was found that 2 exhibits a more potent and broader antibacterial activity than the parent compound 1, and 14 shows unique antibacterial spectrum against resistant strains, whereas 15 has almost no activity.

3′-Episeldomycin 5 (7) was synthesized from seldomycin 5. Reaction of hexa-N-ethoxycarbonylseldomycin 5 (2) with o-nitrobenzenesulfonyl chloride gave penta-N-ethoxycarbonylseldomycin 5-2′,3′-epicyclic carbamate (3) in one step. Hexa-N-ethoxycarbonyl-3′-O-tosylseldomycin 5 or hexa-N-ethoxycarbonyl-3′-O-mesylseldomycin 5, prepared from 2, was also converted into 3 by being heated in weakly basic solvents such as N,N-dimethylformamide or pyridine. Compound 3 was hydrolyzed to give 7. Structure of 7 was confirmed by PMR, CMR, MS, and Δ[M] values. Compound 7 was found to be active against resistant bacteria which carry 3′-O-phosphorylating enzymes. Δ[M] values for vicinal amino groups were shortly discussed.

The spectroscopic characterization of a novel polymorph of metal-free phthalocyanine(τ-form), showing the particular X-ray diffraction peaks, was investigated by comparing the other polymorphs. In this paper, the precise ir spectrum obtained by FTIR and visible absorption spectrum of the τ-form are reported.

2-Aminoethyl, glycyl, (S)-4-amino-2-hydroxybutyl and (S)-4-amino-2-hydroxybutyryl groups were introduced to the 2'-amino group of 4-N-[(S)-4-amino-2-hydroxybutyl]fortimicin B (2). All of the derivatives of this type prepared showed antibacterial activity almost as strong as fortimicin A (1) and were also active against fortimicin A resistant bacteria which can inactivate fortimicin A by producing an inactivating enzyme AAC(3)-I.

The 1, 2' or 6'-amino group of fortimicin A was alkylated or acylated and the antimicrobial activities of the derivatives were compared with each other. 2'-N-Substituted fortimicins A were active against the fortimicin A resistant strain which produced AAC(3)-I. AAC(3)-I is the only enzyme which can inactivate fortimicin A. Among the derivatives prepared in the present study, 2'-N-[(S)-4-amino-2-hydroxybutyl]fortimicin A showed stronger activity than fortimicin A.

播種状表在性光線性汗孔角化症 (DSAP) に併発した多発性の表皮内癌の2例を報告した。第1例は66歳男性で両手背にBowen病を生じ, 第2例は81歳男性で両手背, 頭部に光線角化症を多発して認め, 両者ともに表皮内癌の周囲に多数のDSAPを散在していた。DSAPは巨大汗孔角化症や局面型汗孔角化症とともに皮膚癌の発症母地であり, さらに日光による発癌を呈しやすい病態であると考えた。

7-Deoxy-4(R)-dihydrospectinomycin (7) has been prepared and its structure firmly established by proton magnetic resonance and high resolution mass spectrometry. This spectinomycin analog is devoid of antibiotic activity.

The spatial perturbation of plasma density and internal field perpendicular to the direction of propagation are experimentally investigated, when a high-power pulsed microwave is incident on the plasma whose plasma frequency is close to the applied one. For the microwave power above a certain threshold, the electron density and the electric field show a temporally growing perturbation which increases with the incident power. The properties of the perturbation, including its growth rate, are discussed and compared with the theory for the filamentation instability.

1,6,8-Trimethoxy-3-hydroxymethyl-2-naphthoic acid lactone (IV) was synthesized from benzoic acid in 21 steps. This lactone (IV) was completely identical with authentic dimethyl α-sorigenin, obtained by the methylation of natural α-sorigenin. Herewith the structure of α-sorigenin was confirmed to be 1,8-dihydroxy-6-methoxy-3-hydroxymethyl-2-naphthoic acid lactone (III).

Benzyl alcoholysis and hydrolysis of tetrakis-N-(benzyloxycarbonyl)fortimicin B and further transformation of the solvolysis products are described. Several derivatives of 6-epi-purpurosamine B and fortamine potentially useful for the synthesis of fortimicin analogs are presented.

3′-Episeldomycin 5 (7) was synthesized from seldomycin 5. Reaction of hexa-N-ethoxycarbonylseldomycin 5 (2) with o-nitrobenzenesulfonyl chloride gave penta-N-ethoxycarbonylseldomycin 5-2′,3′-epicyclic carbamate (3) in one step. Hexa-N-ethoxycarbonyl-3′-O-tosylseldomycin 5 or hexa-N-ethoxycarbonyl-3′-O-mesylseldomycin 5, prepared from 2, was also converted into 3 by being heated in weakly basic solvents such as N,N-dimethylformamide or pyridine. Compound 3 was hydrolyzed to give 7. Structure of 7 was confirmed by PMR, CMR, MS, and Δ[M] values. Compound 7 was found to be active against resistant bacteria which carry 3′-O-phosphorylating enzymes. Δ[M] values for vicinal amino groups were shortly discussed.

Fortimicins C, D, and KE are new aminocyclitol antibiotics produced by a mutant of fortimicin-producing organisms. Their structures have been determined by 1H and 13C NMR and mass spectra and chemical degradations. Fortimicin C is 4-N-hydantoylfortimicin B, fortimicin KE is 6'-demethylfortimicin B, and fortimicin D is 4-N-glycylfortimicin KE. The last two antibiotics have purpurosamine C instead of 6-epi-purpurosamine B.

7-Epi-spectinomycin (9) and 7-epi-4(R)-dihydrospectinomycin (10) have been prepared and their structures firmly established by proton magnetic resonance. Both of these spectinomycin analogs are devoid of antibiotic activity.

The four amino groups of fortimicin B(4) could be differentiated from each other and 2'-N-benzyloxycarbonyl-, 2', 6'-di-N-benzyloxycarbonyl-, 2'-N-tert-butoxycarbonyl-, 6'-N-tert-butoxycarbonyl- and 2', 6'-di-N-tert-butoxycarbonyl-fortimicin B (7, 8, 16, 18, 17) were prepared from 4. From these fortimicin B derivatives, selectively protected fortimicin A derivatives 13, 15, 21, 22 and 25 were prepared by combination of procedures of benzyloxycarbonylation or tert-butoxycarbonylation, 4-N-glycylation.

Among the new aminoglycoside antibiotic family for fortimicins, components A, C and D have higher activity compared to their 4-N-deacylated components B and KE. Synthesis and antibacterial activities of 4-N-acyl- and 4-N-alkyl-fortimicin B derivatives are described. 4-N-Acylfortimicin B's, which are relatively unstable in alkaline conditions, were converted to stable 4-N-alkyl derivatives with diborane. The activity is greatly affected by the 4-N-substituents, and the presence of hydrophilic group(s) is necessary to confer activity on the derivatives. 4-N-(2-Aminoethyl)-, 4-N-(4-amino-2-hydroxybutyl)- and 4-N-(2-hydroxy-4-methylaminobutyl)-fortimicin B are the most potent compounds among them.