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1.
Pyogenic spondylodiscitis can cause severe osteolytic and destructive lesions in the spine. Elderly or immunocompromised individuals are particularly susceptible to infectious diseases; specifically, infections in the spine can impair the ability of the spine to support the trunk, causing patients to be bedridden, which can also severely affect the physical condition of patients. Although treatments for osteoporosis have been well studied, treatments for bone loss secondary to infection remain to be elucidated because they have pathological manifestations that are similar to but distinct from those of osteoporosis. Recently, we encountered a patient with severely osteolytic pyogenic spondylodiscitis who was treated with romosozumab and exhibited enhanced bone formation. Romosozumab stimulated canonical Wnt/β-catenin signaling, causing robust bone formation and the inhibition of bone resorption, which exceeded the bone loss secondary to infection. Bone loss due to infections involves the suppression of osteoblastogenesis by osteoblast apoptosis, which is induced by the nuclear factor-κB and mitogen-activated protein kinase pathways, and osteoclastogenesis with the receptor activator of the nuclear factor-κB ligand-receptor combination and subsequent activation of the nuclear factor of activated T cells cytoplasmic 1 and c-Fos. In this study, we review and discuss the molecular mechanisms of bone loss secondary to infection and analyze the efficacy of the medications for osteoporosis, focusing on romosozumab, teriparatide, denosumab, and bisphosphonates, in treating this pathological condition.  相似文献   
2.
A method is proposed to generate categorical colour observer functions (individual colour matching functions) for any field size based on the CIE 2006 system of physiological observer functions. The method combines proposed categorical observer techniques of Sarkar et al with a physiologically-based individual observer model of Asano et al and a clustering technique to produce the optimal set of categorical observers. The number of required categorical observers varies depending on an application with as many as 50 required to predict individual observers' matches when a laser projector is viewed. However, 10 categorical observers are sufficient to represent colour-normal populations for personalized colour imaging. The proposed and recommended categorical observers represent a robust and inclusive technique to examine and quantify observer metamerism in any application of colorimetry.  相似文献   
3.
Anchietia salutaris tea is traditionally used in Brazil to treat allergies, suggesting it contains compounds with antagonistic activity on the allergic mediators. We have evaluated extracts and semi-purified fractions of Anchietia salutaris as a source of compounds having this type of antagonism on the contraction induced in guinea-pig lung parenchymal strips and on platelet aggregation and shape change. After 10 min pre-incubation dichloromethane extracts containing 30 or 100 microg mL(-1) inhibited the contraction induced by prostaglandin D2 (PGD2) in guinea-pig lung parenchymal strips with dose ratios (DR) of 0.76+/-0.14 and 0.93+/-0.19, respectively; the amount of inhibition depended both on the concentration and on the time of pre-incubation (DR after 30 min pre-incubation was 1.21+/-0.51). The dichloromethane extract and its semi-purified fractions also inhibited the contractions induced by U46619, a more potent, stable, synthetic agonist of thromboxane A2 (TxA2) prostanoid (TP) receptors, the receptors acted upon by PGD2 to produce lung contractions. The dichloromethane extract did not inhibit the lung parenchymal contractions induced by histamine, leukotriene D4 (LTD4) or platelet-activating factor (PAF). Platelet aggregation induced by U46619, adenosine 5'-diphosphate (ADP) or PAF was not inhibited by the dichloromethane extract. Indeed, the extract potentiated platelet aggregation induced by low concentrations of these agonists and also potentiated the shape change induced by U46619. These results imply that the dichloromethane extract of Anchietia salutaris and its semi-purified fractions contain an active principle that competitively inhibits TxA2 TP receptors, the stimulation of which causes lung parenchymal contraction. The inhibition seems to be selective for this receptor subtype, because the extract fails to inhibit platelet aggregation or shape change. This provides additional support of earlier reports suggesting the occurrence of TP receptor subtypes.  相似文献   
4.
Structure and mechanical properties of polyethylene-fullerene composites   总被引:1,自引:1,他引:0  
The microhardness of films of fullerene-polyethylene composites prepared by gelation from semidilute solution, using ultrahigh molecular weight polyethylene (PE) (6×106), has been determined. The composite materials were characterized by optical microscopy and X-ray diffraction techniques. The microhardness of the films is shown to increase notably with the concentration of fullerene particles within the films. In addition, a substantial hardening of the composites is obtained after annealing the materials at high temperatures (T a=130 °C) and long annealing times (t a=105s). The hardening of the composites with annealing temperature has been identified with the thickening of the PE crystalline lamellae. Comparison of X-ray scattering data and the microhardness values upon annealing leads to the conclusion of phase separation of C60 molecules from the polyethylene crystals within the material. The temperature dependence is discussed in terms of the independent contribution of the PE matrix of the C60 aggregates to the hardness value.  相似文献   
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6.
We report on a case of adenovirus hemorrhagi cystitis that developed in a 49-year-old woman during intensive chemotherapy for adult T-cell leukemia. Although rapid etiologic diagnosis is essential for the effective management of viral hemorrhagic cystitis, the isolation of adenovirus from urine is often too time-cousuming. We detected the adenovirus antigen in the patient's urine using an Adenoclone direct sandwich ELISA kit (Cambridge Bio Science), which is commonly employed for the diagnosis of adenovirus conjunctivitis. Treatment consisted of intravenous vidarabine and bladder irrigation, which resulted in prompt clinical improvement. The Adenoclone kit was useful for the rapid etiologic diagnosis of adenovirus hemmorrhagic cystitis.  相似文献   
7.
The alpha subunit of Gi2 (Gi2 alpha) is a member of the heterotrimeric G protein family, which transduces receptor signals as a proto-oncogene product. We have found a novel self-suppressive region in Gi2 alpha near its C terminus. A polypeptide consisting of residues 338-352 of Gi2 alpha (Gi2 alpha-339-352) antagonizes receptor- and receptor peptide-stimulated Gi2 alpha activation, without affecting basal activity. Antagonism by Gi2 alpha-338-352 is attributable to an interaction with activated Gi2 alpha, which is not competitive with receptor polypeptides. Combined with the reports suggesting the presence of self-suppressive domains in a juxta-C-terminal portion of Gi2 alpha and G(o) alpha, this study supports the hypothesis that Gi2 alpha-338-352 constitutes an intrinsic guanine nucleotide exchange inhibitor, which in turn antagonizes receptor stimulation, suggesting that G proteins are activated by receptors through relaxation of a self-suppressive conformation.  相似文献   
8.
To clarify the clinicopathological significance of the suppurative lesions without an epithelioid granulomatous response (SLs without Ep) in lymph nodes and their relationship to abscess-forming granulomatous lymphadenitis (AGL) and cat scratch disease (CSD), 10 cases were assessed clinicopathologically and immunohistologically. SLs without Ep were located in the subcapsular sinus, paracortical area and medullary cords, but not in the germinal centers. The microabscesses were surrounded by collections of monocytoid B-lymphocytes (MBLs), histiocytes without epithelioid features, neutrophils, small lymphocytes and small numbers of plasma cells. The majority of the MBLs seen in the SLs without Ep were of the large cell type. The histological triad of toxoplasmic lymphadenitis, i.e., reactive follicular hyperplasia, small clusters of epithelioid cells and aggregates of MBLs, were also seen in all cases. Some of the clinical and pathological findings in our 10 cases were characteristic of CSD, i.e., (1) cat exposure before the lymphadenopathy was in four of the 10 cases, (2) occurrence in autumn and winter months in all cases, (3) typical suppurative granulomas surrounded by palisaded epithelioid cells were in four of the 10 cases, and (4) Warthin-Starry silver stain-positive bacteria were detected in seven of the 10 cases. The results of our study suggest that SLs without Ep are an early stage of CSD.  相似文献   
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10.
A development of 170GHz/500kW level gyrotron was carried out as R&D work of ITER. The oscillation mode is TE31,8. In a short pulse experiment, the maximum power of 750kW was achieved at 85kV/40A. The efficiency was 22%. In the depressed collector operation, 500kW/36%/50ms was obtained. The maximum efficiency of 40% was obtained at PRF=470kW whereas the power decrease by the electron trapping was observed. Pulse extension was done up to 10s at PRF=170kW with the depressed collector operation. The power was limited by the temperature increase of the output window.  相似文献   
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