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Background: The detailed mechanisms of knee osteoarthritis (OA) pain have not been clarified, but involvement of inflammatory cytokines such as tumor necrosis factor-alpha (TNF) has been suggested. The present study aimed to investigate the more detailed neurological involvement of TNF in joint pain using a TNF-knockout mouse OA model. Methods: The right knees of twelve-week-old C57BL/6J wild and TNF-deficient knockout (TNF-ko) mice (n=15, each group) were given a single intra-articular injection of 10 µg monoiodoacetate in 10 mL sterile saline. The left knees were only punctured as the control. Evaluations were performed immediately after the injection (baseline) and at 7, 14, and 28 days after the injection with a subsequent intra-articular injection of neurotracer into both knees. The animals were evaluated for immunofluorescence of the lumbar dorsal root ganglia (DRG) innervating the knee joints. The injected knees were observed macroscopically and mouse pain-related behaviors were scored. Results: Macroscopic observation showed similar knee OA development in both wild and TNF-ko mice. Calcitonin gene-related peptide (CGRP, a neuropeptide identified as a inflammatory pain-related biomarker) was significantly increased in DRG neurons innervating OA-induced knee joints with significantly less CGRP expression in TNF-ko animals. Pain-related behavior scoring showed a significant increase in pain in OA-induced joints, but there was no significant difference in pain observed between the wild and TNF-ko mice. Conclusions: The result of the present study indicates the possible association of TNF-alpha in OA pain but not OA development.  相似文献   
3.
ABSTRACT: BACKGROUND: High salt intake in patients with chronic kidney disease (CKD) may cause high blood pressure and increased albuminuria. Although, the estimation of salt intake is essential, there are no easy methods to estimate real salt intake. METHODS: Salt intake was assessed by determining urinary sodium excretion from the collected urine samples. Estimation of salt intake by spot urine was calculated by Tanaka's formula. The correlation between estimated and measured sodium excretion was evaluated by Pearson's correlation coefficients. Performance of equation was estimated by median bias, interquartile range (IQR), proportion of estimates within 30 % deviation of measured sodium excretion (P30) and root mean square error (RMSE).The sensitivity and specificity of estimated against measured sodium excretion were separately assessed by receiver-operating characteristic (ROC) curves. RESULTS: A total of 334 urine samples from 96 patients were examined. Mean age was 58 +/- 16 years, and estimated glomerular filtration rate (eGFR) was 53 +/- 27 mL/min. Among these patients, 35 had CKD stage 1 or 2, 39 had stage 3, and 22 had stage 4 or 5. Estimated sodium excretion significantly correlated with measured sodium excretion (R = 0.52, P < 0.01). There was apparent correlation in patients with eGFR <30 mL/min (R = 0.60, P < 0.01). Moreover, IQR was lower and P30 was higher in patients with eGFR < 30 mL/min. Estimated sodium excretion had high accuracy to predict measured sodium excretion, especially when the cutoff point was >170 mEq/day (AUC 0.835). CONCLUSIONS: The present study demonstrated that spot urine can be used to estimate sodium excretion, especially in patients with low eGFR.  相似文献   
4.
Toll-like receptors (TLRs) are innate recognition molecules for microbial products, but their direct interactions with corresponding ligands remain unclarified. LPS, a membrane constituent of gram-negative bacteria, is the best-studied TLR ligand and is recognized by TLR4 and MD-2, a molecule associated with the extracellular domain of TLR4. Although TLR4-MD-2 recognizes LPS, little is known about the physical interaction between LPS and TLR4-MD-2. Here, we demonstrate cell surface LPS-TLR4-MD-2 complexes. CD14 greatly enhances the formation of LPS-TLR4-MD-2 complexes, but is not coprecipitated with LPS-TLR4-MD-2 complexes, suggesting a role for CD14 in LPS loading onto TLR4-MD-2 but not in the interaction itself between LPS and TLR4-MD-2. A tentative dissociation constant (Kd) for LPS-TLR4-MD-2 complexes was approximately 3 nM, which is approximately 10-20 times lower than the reported Kd for LPS-MD-2 or LPS-CD14. The presence of detergent disrupts LPS interaction with CD14 but not with TLR4-MD-2. E5531, a lipid A antagonist developed for therapeutic intervention of endotoxin shock, blocks LPS interaction with TLR4-MD-2 at a concentration 100 times lower than that required for blocking LPS interaction with CD14. These results reveal direct LPS interaction with cell surface TLR4-MD-2 that is distinct from that with MD-2 or CD14.  相似文献   
5.
Pancreatic beta-cell survival is critical in the setting of diabetes as well as in islet transplantation. Transgenic mice overexpressing parathyroid hormone-related protein (PTHrP) targeted to beta-cells using the rat insulin II promoter (RIP) display hyperinsulinemia, hypoglycemia, and islet hyperplasia, without a concomitant increase in beta-cell proliferation rate or enlargement of individual beta-cell size. Thus, the mechanism for increased beta-cell mass is unknown. In this study, we demonstrated that beta-cells of transgenic mice are resistant to the cytotoxic effects of streptozotocin (STZ) in vivo, as documented by a sixfold reduction in the rate of STZ-induced beta-cell death in RIP-PTHrP mice relative to their normal siblings. The reduced cell death in transgenic mice is due neither to their increased islet mass nor to a decrease in their sensing of STZ, but rather results from PTHrP-induced resistance to beta-cell death. This is also demonstrated in vitro by markedly reduced cell death rates observed in beta-cells of transgenic mice compared with normal mice when cultured in the absence of serum and glucose or in the presence of STZ. Finally, we demonstrated that NH(2)-terminal PTHrP inhibits beta-cell death. These findings support the concept that PTHrP overexpression increases islet mass in transgenic mice through inhibition of beta-cell death.  相似文献   
6.
Atrazine, one of the most commonly used herbicides in the world, has been reported to have endocrine disrupting effects in vivo. In the present experiment, influence of dietary atrazine on the late promotion/progression stage of mammary carcinogenesis in ovariectomized female Sprague-Dawley rats was examined after a single intragastric administration of 7,12-dimethylbenz(a)anthracene (DMBA). When the incidence of palpable mammary tumors reached about 50%, the animals were subjected to ovariectomy and divided into tumor bearing [DMBA-Tumor(+)] and non-tumor bearing [DMBA-Tumor(-)] groups, with subgroups of each fed a soybean-free diet containing 0, 5, 50, or 500 p.p.m. atrazine for 34 weeks. At the completion of the study, the tumor volume in the 50 and 500 p.p.m. treatment Tumor(+) subgroups was greater than in the 0 p.p.m. control case. In the DMBA-Tumor(-) group, higher incidences and volumes of the mammary tumors, with or without statistical significance (P <0.05), were observed in the 50 and 500 p.p.m. subgroups. Atrazine treatment tended to increase proportion of estrogen receptor alpha-positive tumors and stimulated cell proliferation in the DMBA-Tumor(+) group, but with no clear effects on serum hormone levels. The present study indicates that atrazine has a potential for enhancing the growth of mammary tumors, partly through increasing cell proliferation in the promotion/progression stage in female rats under ovarian hormone-free conditions.  相似文献   
7.
Akt is an important intracellular mediator of beta-cell growth and survival in rodents. However, whether constitutive activation of Akt in human beta-cells enhances the survival and function of transplanted islets is unknown. In the current study, we examined the efficacy of constitutive activation of Akt in improving human islet transplant outcomes using a marginal mass model in diabetic severe combined immunodeficient (SCID) mice. Human islets transduced with adenoviruses encoding constitutively active Akt1 (Adv-CA-Akt) displayed increased total and phosphorylated Akt and Akt kinase activity compared with control islets. Expression of CA-Akt in human islets induced a significant increase in beta-cell replication and a significant decrease in beta-cell death induced by serum and glucose deprivation or chronic hyperglycemia. Two control groups of islets (1,500 uninfected or adenovirus LacZ [Adv-LacZ]-transduced human islet equivalents [IEQs]) transplanted under the kidney capsule of streptozotocin-induced diabetic SCID mice were insufficient to correct hyperglycemia. Importantly and in marked contrast to these controls, 1,500 Adv-CA-Akt-transduced IEQs were capable of restoring euglycemia in diabetic SCID mice. Moreover, blood glucose normalization persisted for at least 6 months. Human plasma insulin at day 54 after transplant was 10-fold higher in Adv-CA-Akt islet recipients (2.4 +/- 0.4 ng/ml) compared with those receiving Adv-LacZ islets (0.25 +/- 0.08 ng/ml) (P < 0.05). In summary, expression of CA-Akt in human islets improves islet transplant outcomes in a subcapsular renal graft model in SCID mice. Akt is an attractive target for future strategies aimed at reducing the number of islets required for successful islet transplantation in humans.  相似文献   
8.
In this case report, we present genetic differences in two morphine-related gene sequences, UDP-glucuronosyltransferase 2B7 (UGT2B7) and mu opioid receptors (MOR1), in two cancer patients whose clinical responses to morphine were very different [i.e., sensitive (patient 1) and low responder (patient 2)]. In addition, allelic variants in the UGT2B7 gene were analyzed in 46 Japanese individuals. Amplified DNA fragments for the two genes of interest were screened using single strand conformation polymorphism and then sequenced. In the UGT2B7 gene, 12 single nucleotide polymorphisms (SNPs) were newly identified with an allelic frequency ranging from 0.022 to 0.978. Six SNPs in the promoter region (A-1302G, T-1295C, T-1111C, G-899A, A-327G, and T-125C) and two coding SNPs (UGT2B7*2 in exon 2 and C1059G in exon 4) appeared to be consistently linked. Remarkable differences in the nucleotide sequence of UGT2B7 were observed between the two patients; in contrast to patient 1 who had "reference" alleles at almost SNP positions, but a rare ATTGAT*2(AT)C haplotype as homozygosity, patient 2 was a homozygous carrier for the predominant GCCAGC*1(TC)G sequence. Serum morphine and two glucuronide concentrations in patient 2 suggest that the predominant GCCAGC*1G sequence was not associated with a "poor metabolizer" phenotype. In the MOR1 gene, patient 1 had no SNPs, whereas patient 2 was a heterozygous carrier for both the G-1784A and A118G alleles. The present study describes substantial differences in genotype patterns of two genes of interest between the two patients. The results necessitate larger trials to confirm these observations in larger case control studies.  相似文献   
9.
Phospholipids containing polymerizable itaconate moieties were synthesized and their formation of liposomes was studied. Although the itaconate phospholipids alone form rather unstable liposomes by ultrasonication, mixtures with other phospholipids such as dipalmitoyl phosphatidylcholine, bis(2,4-octadienoyl) phosphatidylcholine or cholesterol, form stable and single-wall, small sized liposomes. The polymerizability of itaconate phospholipids and the stabilization of such mixed liposomes are discussed.  相似文献   
10.
In 26 patients with lacunar syndromes, emergence of new lacunar infarctions were identified within 13 days from onset by diffusion-weighted magnetic resonance images. The identified lacunar infarctions were repeatedly imaged using fluid-attenuated inversion recovery (FLAIR) sequence up to 600 days from onset. On FLAIR images taken by 23 days from onset, lacunar infarctions showed homogeneous hyperintensity. On the later FLAIR images beyond 25 days from onset they were observed as heterogeneously hyperintense lesions in half of the patients. In the other patients, lacunar infarctions were observed as hypointense areas with a hyperintense rim beyond 41 days from onset, which indicates cystic transformation with surrounding gliosis. These FLAIR images of lacunar infarction differ from those of dilated perivascular space which is observed as an area of simple hypointensity.  相似文献   
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