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Notes: . Blastocystis hominis, a parasite of the human intestine, has recently been positioned within Stramenopiles by the small subunit rRNA phylogeny. To further confirm its phylogenetic position using multiple molecular sequence data, we determined the nucleotide sequences putatively encoding small subunit ribosomal RNA, cytosolic-type 70-kDa heat shock protein, translation elongation factor 2, and the non-catalytic ‘B’ subunit of vacuolar ATPase of B. hominis (HE87–1 strain). Moreover, we determined the translation elongation factor 2 sequence of an apicomplexan parasite, Plasmodium falciparum, that belongs to alveolates. The maximum likelihood analyses of small subunit rRNA and cytosolic-type 70-kDa heat shock protein clearly demonstrated that B. hominis (HE87–1 strain) is positioned within Stramenopiles, being congruent with the previous small subunit rRNA analysis, including the sequences of B. hominis (Nand strain) and a Blastocystis isolate from guinea pig. Although no clear resolution among major eukaryotic groups was obtained by the individual phytogenies based on the four molecules analyzed here, a combined analysis of various molecules, including these, clearly indicated that Blatocystis/stramenopiles are the closest relatives of alveolates.

Notes: Abstract OPLL (ossification of the posterior longitudinal ligament of the spine) is a common form of human myelopathy with a prevalence of as much as 4% in a variety of ethnic groups. To clarify the genetic factors that predispose to OPLL, we have studied ttw (tiptoe walking), a mouse model that presents ectopic ossification of the spinal ligaments similar to OPLL and have found that the ttw phenotype is caused by the nonsense mutation of the gene encoding nucleotide pyrophosphatase (NPPS), a membrane-bound glycoprotein thought to produce inorganic pyrophosphate, a major inhibitor of calcification and mineralization. To investigate a possible role of NPPS in the etiology of OPLL, we have examined its genetic variations in OPLL patients. A total of 323 OPLL patients was screened by means of polymerase chain reaction/single-strand conformation polymorphism analysis covering all the exons and their surrounding introns, plus about 1.5-kb of the promoter region. We identified ten nucleotide variations in the NPPS gene; five of the alterations caused amino-acid substitutions, and two of them were found specifically in OPLL patients. Subsequently, we performed an association study using these variations and found a significant association of an allele, viz., a deletion of T at a position 11 nucleotides upstream from the splice acceptor site of intron 20 (IVS20–11delT), with OPLL; the proportion of the individuals having this deletion was significantly higher (P = 0.0029) in OPLL patients than in controls, indicating that those who have this variation may be more susceptible to the abnormal ossification of the spinal ligaments. Thus, our study suggests that NPPS plays an important role in the etiology of human OPLL.

Notes: It is well known that two different photobiologic processes mainly take place when the human skin is exposed to ultraviolet (UV) light. The long waves of UVA and visible light (320–400 nm) irradiation causes skin tanning by melanocytic activation and the short waves of UVB (280–320 nm) can elicit variety of biologic action in cutaneous keratinocytes, melanocytes and other skin component cells. The sensitivity to the UV lights is generally depending on the three kinds of the skin type classified by the proposal of Pathak et al. [1]. The skin sensitivity of Japanese population, however, seems to be different from that of Caucasian's population because of the differences in genetic background and skin color, as indicated by Satoh and Kawada [2]. They tried to classify into three groups as J-I (always burn and rarely tan), J-II (moderately burn and moderately tan) and J-III (never burn and always tan) by the skin types to UV lights for the sun-tanning and sun-burning. Comparing these two criteria, a general concern indicates that J-I–III may correspond to the skin type II–IV of the Fitzpatrick's classification, respectively. Based on the Japanese skin types, the incidence of skin cancers and precancerous lesions related to the long-term exposure of sun-light was epidemiologically estimated by Araki et al. [3]. According to their results for several years (1992–1998), the overall number of skin cancers and precancerous states in Japanese was demonstrated to be small in comparison with the incidence of Caucasian's population, even though the people sets in areas of higher ambient solar radiation. However, working outdoors having J-I and/or a history of severe sunburn during childhood were found to be important risk factors, particularly among people of over 60 years of age. Regarding skin cancers and sun-exposed areas, we compared between 20 patients with skin cancers (males 13 and females seven) (average 65 years old) (〈link href="#t1-14"〉Table I) and 24 controls (males 10 and females 14), who were selected as similar ages to the patients at random, in their skin types and life environments by a questionnaire system. The skin types of the patients were J-I (15%), J-II (40%), and J-III (35%) and those of controls were J-I (4.2%), J-II (62.5%), and J-III (4.2%), respectively. The patient group tended not to protect from sun exposure and most of them were farmers. UV exposure is known to induce modulation of the skin immune system which Langerhans cells decrease in number in the epidermis, and on the other hand it is supposed that interleukin IL-10 producing macrophages (CD11b+) expand in the dermis. Not only IL-10, but also tumor necrosis factor (TNF)-α from macrophages and mast cells in the dermis seem to increase and suppress Th1 immune responses of the epidermis and Th2 immune responses might be induced by UV irradiation [4]. Recently, it has been reported, however, that in patients with polymorphous light eruption (PLE), the expression of TNF-α, IL-4, and IL-10 is reduced by UVB irradiation and that PLE appearance is related to UVB-induced immunosuppression [5].〈tabular xml:id="t1-14"〉I〈title type="main"〉 Twenty patients with skin cancers (average ages: 65 years old) (Department of Dermatology, Fukushima Medical University Hospital, 2001–2002) 〈table frame="topbot"〉〈tgroup cols="2" align="left"〉〈colspec colnum="1" colname="col1"/〉〈colspec colnum="2" colname="col2"/〉〈thead valign="bottom"〉〈row rowsep="1"〉Skin cancersNumber of patients〈tbody valign="top"〉Malignant melanoma8Squamous carcinoma4Bowen's disease4Basal cell carcinomas3Eccrine porocarcinoma1Location of skin cancersSun-exposed areas9Non-exposed areas11Then, we attempted to study UVB effects on atopic disease and chronic inflamed skin diseases in the therapeutic advantage, although it is harmful for the patients to be cutaneous carcinogenesis. The epidermal keratinocytes are capable of producing CC chemokines in the local Th2 response, as seen in atopic dermatitis, mycosis fungoides, etc. [6]. Thymus and activated-related chemokine (TARC) is one of the chemokines produced by keratinocytes which selectively activate lymphocytes of Th2 subset expressing CCR4 (receptor for TARC) [7]. Accumulating evidence has suggested that these chemokines have primary pathogenic importance in Th2 skin diseases. In order to find the effects of UVB irradiation on the production of TARC, we used a human keratinocyte HaCaT cell line. As assessed by RT-PCR and ELISA, UVB irradiation significantly decreased the expression of TARC mRNA and protein in HaCaT cells stimulated with interferon-γ (IFN-γ) and TNF-α in a dose-dependent manner. The down-regulation of TARC expression may be mediated in part by activation of the particular transcription, signal transducer and activator of transcription 1 (STAT 1), since it has shown that STAT 1 DNA-binding was down-regulated by UVB irradiation. Our results suggest that STAT 1 and other transcription factors play an important biological role in immune system of human skin irradiated by UVB and may support the results of Kolgen et al. [5].In this point of view, UVB irradiation will be a therapeutic tool for skin diseases related to Th2 type reaction, such as atopic dermatitis, mycosis fungoides, etc., although we need to optimize adequately the use of UVB in patients with J-I skin type or those of whom have the episode of severe sun-burn after UVB irradiation.〈section xml:id="abs1-1"〉〈title type="main"〉References1. Pathak, M.A., Nghiem, P. and Fitzpatrick, T.B. Acute and chronic effects on the skin. In: Fitzpatrick's Dermatology in General Medicine, 5th edn (Freedberg, I.M., Eisen, A.Z., Wolf, K., Austen, K.F., Goldsmith, L.A., Katz, S.I. and Fitzpatrick, T.B. eds), pp. 1598–1607. McGraw-Hill, New York (1999).2. Satoh, Y. and Kawada, A. Action spectrum for melanin pigmentation to ultraviolet light, and Japanese skin typing. In: Brown Melanoderma: Biology and Diseases of Epidermal Pigmentation (Fitzpatrick, T.B., Wick, M.M. and Toda, K. eds), pp. 87–95. University of Tokyo Press, Tokyo (1986).3. Araki, K., Nagano, T., Ueda, M., Washio, F., Watanabe, S., Yamaguchi, N. and Ichihashi, M. Incidence of skin cancers and precancerous lesions in Japanese- Risk factors and prevention. J. Epidemiol. 9, S14–S21 (1999).4. Teunissen, M. B., Piskin, G., Nuzzo, S. et al. Ultraviolet B radiation induces a transient appearance of IL-4+ neutrophils, which support the development of Th2 responses. J Immunol. 168, 3732–3739 (2002).5. Kolgen, W., van Meurs, M., Jongsma, M. et al. Differential expression of cytokines in UVB-exposed skin of patients with polymorphous light eruption. Arch. Dermatol. 140, 295–302 (2004).6. Kakinuma, T., Sugaya, M., Nakamura, K., Kaneko, F., Wakugawa, M., Matsushima, K. and Tamaki, K. Thymus and activation-regulated chemokine (TARC/CCL17) in mycosis fungoides: serum TARC levels reflect the disease activity of mycosis fungoides. J. Am. Acad. Dermatol. 48, 23–30 (2003).7. Imai, T., Nagira, M., Tkagi, S. et al. Selective recruitment of CCR4-binding Th2 cells toward antigen-presenting cells by the CC chemokins thymus and activation-regulated chemokine and macrophage-derived chemokine. Int. Immunol. 11, 81–88 (1999).

Notes: We study single-carrier traps in a GaAs/AlxGa1−xAs heterostructure by observing random telegraph signals (RTSs), which are caused by the traps having energy levels within a few kBT of the Fermi level. RTSs are observed in a split gate device while a narrow channel is shifted by independently controlling the voltage applied to each part of the split gate. This measurement reveals the variations of the energy levels of traps with the channel position. From these variations the locations and the energy distributions of the traps are demonstrated. The strength of the confinement potential around the trap is also discussed. © 1995 American Institute of Physics.

Notes: Beam position stability was found to be largely affected by the distortion of the storage ring building, especially when the beam emittance was lowered. Building distortion in the horizontal direction was noticed as the diurnal deviation of the orbit circumference. The deviation was measured by reading the amount of rf frequency variation necessary to recover the horizontal central orbit. The deviation of the orbit circumference was interpreted to be induced from the ring floor expansion. Such diurnal expansion of the ring floor was evaluated by using a model simulation that dealt with the distortion of the ring building under thermal stress. To reduce such thermal stress, the rooftop of the building was insulated. The deviation of the ring circumference measured after insulation was reduced to one-half of that measured before. The simulation also gave the same amount of deviations as measured before and after insulation.

Notes: Rotational transition in atom–diatom chemical reaction is theoretically studied. A new approximate theory (which we call IOS-DW approximation) is proposed on the basis of the physical idea that rotational transition in reaction is induced by the following two different mechanisms: rotationally inelastic half collision in both initial and final arrangement channels, and coordinate transformation in the reaction zone. This theory gives a fairy compact expression for the state-to-state transition probability. Introducing the additional physically reasonable assumption that reaction (particle rearrangement) takes place in a spatially localized region, we have reduced this expression into a simpler analytical form which can explicitly give overall rotational state distribution in reaction. Numerical application was made to the H+H2 reaction and demonstrated its effectiveness for the simplicity. A further simplified most naive approximation, i.e., independent events approximation was also proposed and demonstrated to work well in the test calculation of H+H2. The overall rotational state distribution is expressed simply by a product sum of the transition probabilities for the three consecutive processes in reaction: inelastic transition in the initial half collision, transition due to particle rearrangement, and inelastic transition in the final half collision.