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61.
《Cytokine》2015,74(2):245-252
BackgroundWe aimed to investigate the use of novel serum biomarkers for predicting the recurrence and survival of patients with hepatitis B virus (HBV)-related early hepatocellular carcinoma (HCC) after hepatic resection or radiofrequency ablation (RFA).MethodsOne hundred and five patients with HBV-related HCC, who fulfilled the Milan criteria without vascular invasion and underwent hepatic resection or RFA, were followed-up for a median duration of 52 months. Pretreatment serum concentrations of 16 cytokines including interleukin-6 (IL-6) were measured by using a Luminex 200 system. The measured serum cytokines and several clinical factors were analyzed retrospectively.ResultsUnivariate analysis showed that patients with lower pretreatment serum levels of IL-10, IL-6, monocyte chemoattractant protein-1, and tumor necrosis factor-α had significantly shorter disease-free survival (DFS) than those with higher levels. Multivariate analysis revealed that a low serum IL-6 level (⩽33.00 pg/mL; hazard ratio [HR] = 5.39; 95% confidence interval [CI] = 1.27–22.93; P = 0.022), low platelet count (<100 × 109/L; HR = 2.23; 95% CI = 1.28–3.89; P = 0.005), and low serum albumin level (⩽3.5 g/L; HR = 2.26; 95% CI = 1.28–3.97; P = 0.005) had a negative prognostic impact on DFS. In the analysis for overall survival, a low serum platelet level (<100 × 109/L; HR = 2.80; 95% CI = 1.31–5.99; P = 0.008) and multiple tumor (⩾2; HR = 4.05; 95% CI = 1.56–10.48; P = 0.004) showed a negative prognostic impact on the overall survival.ConclusionA low serum IL-6 level is, in addition to low platelet count and low serum albumin level, an independent prognostic factor for DFS in patients with HBV-related early HCC who underwent hepatic resection or RFA with curative intention. 相似文献
62.
63.
Summary Two previously identified forms of macrophage were investigated in primary cultures of cerebral cortical cells. Dynamic features were revealed through time-lapse video recording and aspects of macrophage function were assessed. The two cell forms were shown to be different pre-mitotic stages of a single cell type. The cell cycle for these cells involved an initial large, flat, quiescent cell which retracted to yield a slightly rounded form with numerous processes. This latter form lost processes and developed profuse filopodia as it became very rounded just prior to division; both resulting daughter cells then regained the initial large flat appearance. These cells possessed several properties of macrophages, including phagocytosis, nucleoside diphosphatase enzyme, and CR3 receptors. These properties were transient, expressed just before and after mitosis, but subsequently down-regulated in the flat daughter cells. Because of this feature, it was difficult to determine the exact size of this cell population; however, the observed rate of proliferation suggests it may be substantial. It is suggested that these cells correspond to non-microglial macrophages of brain tissue and, because of their significant down-regulation, they may be difficult to detect. This may be important in studies of brain accessory immune cells in tissue culture. 相似文献
64.
Khashayar Afshari Nazgol-Sadat Haddadi Arvin Haj-Mirzaian Mohammad Hosein Farzaei Mohammad Mojtaba Rohani Freshteh Akramian Rozita Naseri Antoni Sureda Negar Ghanaatian Amir Hossein Abdolghaffari 《Journal of cellular physiology》2019,234(12):21519-21546
Flavonoids comprise a group of natural polyphenols consisting of more than 5,000 subtypes mostly existing in fruits and vegetables. Flavonoids consumption could potentially attenuate the incidence and recurrence risk of colorectal cancers through their antiperoxidative, antioxidant, and anti-inflammatory effects. In addition, these compounds regulate the mitochondrial function, balance the bacterial flora and promote the apoptosis process in cancerous cells. However, some previous data failed to show the effectiveness of flavonoids in reducing the risk of colorectal cancer. In this study, we have reviewed the efficacy of different flavonoids subtypes on the risk of colon cancer and molecular mechanisms involved in this process in both clinical and animal studies. In addition, we tried to elucidate the potential synergy between these compounds and current colorectal cancer treatments. 相似文献
65.
PurposeThe purpose of this study was to design and develop a new range optimization for target and organs at risk (OARs) in dynamic adaptive proton beam therapy (PBT).MethodsThe new range optimization for target and OARs (RO-TO) was optimized to maintain target dose coverage but not to increase the dose exposure of OARs, while the other procedure, range optimization for target (RO-T), only focused on target dose coverage. A retrospective analysis of a patient who received PBT for abdominal lymph node metastases was performed to show the effectiveness of our new approach. The original plan (OP), which had a total dose of 60 Gy (relative biological effectiveness; RBE), was generated using six treatment fields. Bone-based registration (BR) and tumor-based registration (TR) were performed on each pretreatment daily CT image dataset acquired once every four fractions, to align the isocenter.ResultsBoth range adaptive approaches achieved better coverage (D95%) and homogeneity (D5%−D95%) than BR and TR only. However, RO-T showed the greatest increases in D2cc and Dmean values of the small intestine and stomach and exceeded the limitations of dose exposure for those OARs. RO-TO showed comparable or superior dose sparing compared with the OP for all OARs.ConclusionsOur results suggest that BR and TR alone may reduce target dose coverage, and that RO-T may increase the dose exposure to the OARs. RO-TO may achieve the planned dose delivery to the target and OARs more efficiently than the OP. The technique requires testing on a large clinical dataset. 相似文献
66.
Mohammad Rahmati Behrooz Johari Mehdi Kadivar Elham Rismani Yousef Mortazavi 《Journal of cellular physiology》2020,235(6):5429-5444
67.
《Peptides》2014
The frog skin host-defense peptide tigerinin-1R (RVCSAIPLPICH.NH2) is insulinotropic both in vitro and in vivo. This study investigates the effects on insulin release and cytotoxicity of changes in cationicity and hydrophobicity produced by selected substitutions of amino acids by l-arginine, l-lysine and l-tryptophan. The [A5W], [L8W] and [I10W] analogs produced a significant (P < 0.01) increase in the rate of insulin release from BRIN-BD11 rat clonal β cells at concentration of 0.01 nM compared with 0.1 nM for tigerinin-1R. The increase in the rate of insulin release produced by a 3 μM concentration of the [S4R], [H12K], and [I10W] analogs from both BRIN-BD11 cells and mouse islets was significantly greater (P < 0.05) than that produced by tigerinin-1R. No peptide stimulated the release of lactate dehydrogenase at concentrations up to 3 μM indicating that plasma membrane integrity had been preserved. [A5W] tigerinin-1R was the only analog tested that showed cytotoxic activity against human erythrocytes (LC50 = 265 ± 16 μM) and inhibited growth of Escherichia coli (MIC = 500 μM) and Staphylococcus aureus (MIC = 250 μM). The circular dichroism spectra of tigerinin-1R and [A5W] tigerinin-1R indicate that the peptides adopt a mixture of β-sheet, random coil and reverse β-turn conformations in 50% trifluoroethanol/water and methanol/water. Administration of [S4R] tigerinin-1R (75 nmol/kg body weight) to high-fat fed mice with insulin resistance significantly (P < 0.05) enhanced insulin release and improved glucose tolerance over a 60 min period following an intraperitoneal glucose load. The study supports the claim that tigerinin-1R shows potential for development into novel therapeutic agents for treatment of type 2 diabetes mellitus. 相似文献
68.
《Phytomedicine》2014,21(3):356-362
Trans-caryophyllene is a sesquiterpene present in many medicinal plants’ essential oils, such as Ocimum gratissimum and Cannabis sativa. In this study, we evaluated the antinociceptive activity of trans-caryophyllene in murine models of acute and chronic pain and the involvement of trans-caryophyllene in the opioid and endocannabinoid systems. Acute pain was determined using the hot plate test (thermal nociception) and the formalin test (inflammatory pain). The chronic constriction injury (CCI) of the sciatic nerve induced hypernociception was measured by the hot plate and von Frey tests. To elucidate the mechanism of action, mice were pre-treated with naloxone or AM630 30 min before the trans-caryophyllene treatment. Afterwards, thermal nociception was evaluated. The levels of IL-1β were measured in CCI-mice by ELISA. Trans-caryophyllene administration significantly minimized the pain in both the acute and chronic pain models. The antinociceptive effect observed during the hot plate test was reversed by naloxone and AM630, indicating the participation of both the opioid and endocannabinoid system. Trans-caryophyllene treatment also decreased the IL-1β levels. These results demonstrate that trans-caryophyllene reduced both acute and chronic pain in mice, which may be mediated through the opioid and endocannabinoid systems. 相似文献
69.
Liver plasma membranes prepared from genetically diabetic (db/db) mice expressed levels of Gi α-2, Gi α-3 and G-protein β-subunits that were reduced by some 75, 63 and 73% compared with levels seen in membranes from lean animals. In contrast, there were no significant differences in the expression of the 42 and 45 kDa forms of Gs α-subunits. Pertussis toxin-catalysed ADP-ribosylation of membranes from lean animals identified a single 41 kDa band whose labelling was reduced by some 86% in membranes from diabetic animals. Cholera toxin-catalysed ADP-ribosylation identified two forms of Gs α-subunits whose labelling was about 4-fold greater in membranes from diabetic animals compared with those from lean animals. Maximal stimulations of adenylyl cyclase activity by forskolin (100 μM), GTP (100 μM), p[NH]ppG (100 μM), NaF (10 mM) and glucagon (10 μM) were similar in membranes from lean and diabetic animals, whereas stimulation by isoprenaline (100 μM) was lower by about 22%. Lower concentrations (EC50-60 nM) of p[NH]ppG were needed to activate adenylyl cyclase in membranes from diabetic animals compared to those from lean animals (EC50-158 nM). As well as causing activation, p[NH]ppG was capable of eliciting a pertussis toxin-sensitive inhibitory effect upon forskolin-stimulated adenylyl cyclase activity in membranes from both lean and diabetic animals. However, maximal inhibition of adenylyl cyclase activity in membranes from diabetic animals was reduced to around 60% of that found using membranes from lean animals. Pertussis toxin-treatment in vivo enhanced maximal stimulation of adenylyl cyclase by glucagon, isoprenaline and p[NH]ppG through a process suggested to be mediated by the abolition of functional Gi activity. The lower levels of expression of G-protein β-subunits, in membranes from diabetic compared with lean animals, is suggested to perturb the equilibria between holomeric and dissociated G-protein subunits. We suggest that this may explain both the enhanced sensitivity of adenylyl cyclase to stimulation by p[NH]ppG in membranes from diabetic animals and the altered ability of pertussis and cholera toxins to catalyse the ADP-ribosylation of G-proteins in membranes from these two animals. 相似文献
70.
P. Pellegrini Anna Maria Berghella T. Del Beato Sergio Cicia Domenico Adorno Carlo Umberto Casciani 《Cancer immunology, immunotherapy : CII》1996,42(1):1-8
Recent theories have established that, during an ongoing immune response, the lymphokines produced by TH1 and TH2 subsets
of CD4+ T cells are critical to the effectiveness of that response. In vivo and in vitro studies have demonstrated that the type
of environmental cytokines plays a determinant role in directing the development of naive T cells into TH1 or TH2 effector
cells. Disregulated expansion of one or other subset may contribute to the development of certain diseases. To establish whether
a similar situation might exist in the cells of the peripheral blood (PBMC) of colorectal cancer patients, we have performed
immunological studies on a group of patients and a group of healthy subjects. We examined the interleukin-2 (IL-2), interferon
γ (IFNγ), IL-4, IL-6 and tumour necrosis factor α levels in serum; the production of IL-4 and IL-2, with and without activating
agents, by PBMC, tumour-draining lymph node lymphocytes and tumour cells; and the proliferative response of PBMC to IL-2,
IL-4 and anti-CD3 monoclonal antibody (anti-CD3), which were variously combined. The data of the present study lead us to
hypothesize that, because of suppressive effects probably due to environmental IL-4, in the peripheral blood of patients there
seems to be a disregulation in the functionality of TH1 and TH2 subsets of CD4+ T cells, with an expansion in TH2 and a malfunction in TH1 cells. Moreover it seems that this disregulation increases with
as the disease progresses through the stages, suggesting that it can be directly implicated in the mechanisms that allow the
tumour to locate and progress in the host.
Received: 27 June 1995 / Accepted: 13 November 1995 相似文献