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Chronic graft-versus-host disease (cGVHD) is a frequent complication of allogenic bone marrow transplantation. Even with aggressive treatment, cGVHD is associated with a significant degree of morbidity and mortality. cGVHD resembles autoimmune disorder, particularly systemic sclerosis (SSc). Sarpogrelate hydrochloride (SH) is an antagonist of the 5-hydroxytryptamine2A (5HT2A) receptor and has been reported to be effective in the treatment of systemic sclerosis (SSc) patients with Raynaud phenomenon. We used SH to treat a cGVHD patient, and we measured plasma PDGF and total TGF-beta levels. After SH treatment, his plasma PDGF and total TGF-beta levels decreased, and he noticed improvement in his skin pigmentation. In the present case, SH may have improved the skin lesion by inhibiting the synthesis of PDGF and TGF-beta.  相似文献   
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OBJECTIVE: Previous reports have suggested an interplay between the pathways mediating coagulation and inflammation in endotoxemia and sepsis. The present study was designed to examine whether cross-signaling between the pathways mediating coagulation and inflammation occurs, as suggested by the pattern of cytokine production observed following tissue-factor (TF)-induced disseminated intravascular coagulation (DIC). DESIGN: Prospective, comparative, experimental study. SETTING: Laboratory at a university hospital. SUBJECTS: Male Wistar rats, aged 6-7 wks, and weighing 160-170 g. INTERVENTIONS: Male Wistar rats were administered TF (3.75 units/kg every 4 hrs), TF, and tranexamic acid (TA; 50 mg/kg every 4.5 hrs) or lipopolysaccharide (30 mg/kg every 4 hrs) via the tail vein, and blood was sampled at 0, 4, 8 and 12 hrs. MEASUREMENTS AND MAIN RESULTS: Subsequent alterations in thrombin-antithrombin complex and fibrinogen levels, as well as platelet counts, indicated that the severity of both types of experimental DIC (TF-induced and lipopolysaccharide-induced) was similar with respect to hemostatic activation and development of consumption coagulopathy. In lipopolysaccharide-induced DIC, a sharp increase in plasma tumor necrosis factor levels was observed at 4 hrs, after which a sharp decline was noted. Plasma levels of interleukin-6 were markedly increased at 4 hrs, after which a sustained elevation was observed for the duration of the experimental period (tumor necrosis factor, 1270 +/- 280, 180 +/- 40, and 120 +/- 30 pg/mL at 4, 8 and 12 hrs, respectively; interleukin-6, 5810 +/- 1320, 4850 +/- 730, and 5230 +/- 1280 pg/mL at 4, 8 and 12 hrs, respectively). On the other hand, tumor necrosis factor and interleukin-6 were not detected following TF-induced DIC (0 +/- 0 at 4, 8, and 12 hrs for both tumor necrosis factor and interleukin-6). In the TF+TA group, significant increases in tumor necrosis factor and interleukin-6 were observed, compared with the TF group. CONCLUSIONS: There is no overt interplay between the pathways mediating coagulation and inflammation in TF-induced DIC, as observed in lipopolysaccharide-induced DIC.  相似文献   
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Background and Purpose

Bone cancer pain is chronic and often difficult to control with opioids. However, recent studies have shown that several opioids have distinct analgesic profiles in chronic pain.

Experimental Approach

To clarify the mechanisms underlying these distinct analgesic profiles, functional changes in the μ-opioid receptor were examined using a mouse femur bone cancer (FBC) model.

Key Results

In the FBC model, the Bmax of [3H]-DAMGO binding was reduced by 15–45% in the periaqueductal grey matter (PAG), region ventral to the PAG (vPAG), mediodorsal thalamus (mTH), ventral thalamus and spinal cord. Oxycodone (10−8–10−5 M) and morphine (10−8–10−5 M) activated [35S]-GTPγS binding, but the activation was significantly attenuated in the PAG, vPAG, mTH and spinal cord in the FBC model. Interestingly, the attenuation of oxycodone-induced [35S]-GTPγS binding was quite limited (9–26%) in comparison with that of morphine (46–65%) in the PAG, vPAG and mTH, but not in the spinal cord. Furthermore, i.c.v. oxycodone at doses of 0.02–1.0 μg per mouse clearly inhibited pain-related behaviours, such as guarding, limb-use abnormalities and allodynia-like behaviour in the FBC model mice, while i.c.v. morphine (0.05–2.0 μg per mouse) had only partial or little analgesic effect on limb-use abnormalities and allodynia-like behaviour.

Conclusion and Implications

These results show that μ-opioid receptor functions are attenuated in several pain-related regions in bone cancer in an agonist-dependent manner, and suggest that modification of the μ-opioid receptor is responsible for the distinct analgesic effect of oxycodone and morphine.  相似文献   
88.
We have analysed the influence of neighbouring base sequences on the mutagenesis induced by 7,8-dihydro-8-oxoguanine (8-oxoG or G(o)), a typical oxidative lesion of DNA, using the yeast oligonucleotide transformation technique. Two oligonucleotides, oligo-CCG(o) and oligo-CGG(o), each possessing a single 8-oxoG residue and represented by the sequences 5'-CCG(o)-3' and 5'-CGG(o)-3', respectively, were introduced into a chromosome of Saccharomyces cerevisiae and their mutagenic potentials were compared. In a wild-type strain, 8-oxoG showed very weak mutagenic potential in both cases. However, the lesion in 5'-CCG(o)-3' can cause efficient G-to-T transversion in a strain lacking the rad30 gene which encodes yeast DNA polymerase eta (Ypoleta). To explore the properties associated with this translesion synthesis (TLS), the same two oligonucleotides possessing an 8-oxoG were used as templates for a standing-start primer extension assay, and the nucleotide incorporation opposite 8-oxoG was investigated. We found that dATP incorporation opposite 8-oxoG with Ypoleta was low for both sequences. In particular, very low dATP incorporation was observed for the 5'-CCG(o)-3' sequence. These results account for the efficient inhibition of mutagenesis by Ypoleta. TLS plays an important role in one DNA sequence in terms of avoiding mutagenesis induced by 8-oxoG in yeast. In contrast, human yeast DNA polymerase eta showed higher dATP incorporation rates even with the 5'-CCG(o)-3' sequence.  相似文献   
89.
The ability of a commercially available dual bias, dual MOSFET dosimetry system to measure therapeutic doses reproducibly throughout its vendor-defined dose-based lifetime has been evaluated by characterizing its sensitivity variation to integrated/cumulative doses from,high-energy (6 and 15 MV) photon radiotherapy beams. The variation of sensitivity as a function of total integrated dose was studied for three different dose-per-fraction levels; namely, 50, 200, and 1200 cGy/fraction. In standard sensitivity mode (i.e., measurements involving dose-per-fraction levels > or =100 cGy), the response of the MOSFET system to identical irradiations increased with integrated dose for both energies investigated. Dose measurement reproducibility for the low (i.e., 50 cGy) dose fractions was within 2.1% (if the system was calibrated before each in-phantom measurement) and 3.1% [if the system was calibrated prior to first use, with no intermediate calibration(s)]. Similarly, dose measurement reproducibility was between 2.2% and 6.6% for the conventional (i.e., 200 cGy) dose fractions and between 1.8% and 7.9% for escalated (i.e., 1200 cGy) dose fractions. The results of this study suggest that, due to the progressively increasing sensitivity resulting from the dual-MOSFET design, frequent calibrations are required to achieve measurement accuracy of < or =3% (within one standard deviation).  相似文献   
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