High expression of AURKA and AURKB is associated with unfavorable cytogenetic abnormalities and high white blood cell count in patients with acute myeloid leukemia

In the present study, we analyzed AURKA and AURKB gene expression in 70 acute myeloid leukemia (AML) patients. There was no difference between leukemic samples and bone marrow mononuclear cells (BMMCs, n = 8) or CD34(+) progenitors (n = 10) from healthy donors. High white blood cells (WBC) counts were observed in the AURKA(+) and AURKB(+) groups, but no significant differences regarding age, gender, platelet counts or frequency of FLT3-ITD mutations. AURKA, but not AURKB, expression was independently associated with high WBC counts (OR: 3.15, 95% CI 1.07-9.24, p = 0.03). Moreover, the majority of cases that overexpressed AURKA and AURKB presented unfavorable cytogenetic abnormalities (p < 0.001). In conclusion, we described a significant association between overexpression of AURKA/B and cytogenetics findings in AML, which may be relevant to new therapeutic approaches, based on Aurora kinase inhibitors. (C) 2010 Elsevier Ltd. All rights reserved.

Abnormal cell-cycle expression of the proteins p27, mdm2 and cathepsin B in oral squamous-cell carcinoma infected with human papillomavirus

Since the role of human papillomavirus (HPV) infection in oral carcinogenesis is still unclear, the purpose of this study was to verify the association between the expression of p27, mdm2 and cathepsin B and by HPV-related oral lesions. Fifty-five oral biopsies were studied and HPV detection and typing (6/11, 16, 18, 31 and 33) were performed using polymerase chain reaction techniques. The distribution p27, mdm2 and cathepsin B was determined by immunohistochemistry. Twenty-one (38%) out of the 55 oral lesions tested positive for HPV, of which 6(33%) were HPV 6/11, 1 (5%) was HPV 16,14 (72%) were HPV 18 and none was HPV 33/31. Among the 55 biopsies, immunopostivity for p27, mdm2 and cathepsin B was observed in 17 (30.9%), 37 (67.2%) and 37 (67.2%), respectively. Among 21 HPV-positive oral lesions, immunopostivity of mdm2, p27 and cathepsin B was found, respectively, in 6 (33%) out of 18 benign lesions (BL), 4(22%) out of 18 potential malignant epithelial lesions (PMEL) and 11(57.9%) out of 19 malignant lesions (ML). High-risk HPV types may be associated with oral carcinoma, by cell-cycle control dysregulation, contributing to oral carcinogenesis and the overexpression of mdm2, p27 and cathepsin B. (C) 2009 Elsevier GmbH. All rights reserved.

BUBR1 expression in benign oral lesions and squamous cell carcinomas: Correlation with human papillomavirus

Oral squamous Cell carcinoma (OSCC) is the most common head and neck cancer. Only in Brazil, the estimate is for 14,160 new cases in 2009. HPV is associated with increasing risk of oral cancer, but its role in carcinogenesis is still controversial. BUBR1, all important protein in the mitotic spindle assembly checkpoint (SAC), has been associated with some virus-encoded proteins and cancer. The aim of the present study was to evaluate the expression of BUBR1 in non-malignant oral lesions and OSCC with and without metastasis associated with HPV infection. We performed immunohistochemistry for BUBR1 in 70 OSCC biopsies divided into three groups (in situ tumors, invasive tumors without metastasis and invasive tumors with metastasis) with their respective lymph nodes from samples with metastasis and in 16 non-malignant oral lesions. PCR was performed in order to detect HPV DNA. Significantly higher BUBR1 expression associated with shorter survival (p=0.0479) was observed in malignant lesions. There was also it significant correlation (r=1.000) with BUBR1 expression in lesions with metastasis and their lymph nodes. Ninety percent of OSCC and 100% of benign lesions were HPV positive. HPV16 and HVP18 were present in 13 and 24% of HPV-positive OSCC samples, respectively. HPV was more prevalent (76%) in samples with a high BUBR1 expression and the absence of viral DNA had no influence oil BUBR1 expression. These findings suggest that HPV could be associated with overexpression of BUBR1 in OSCC. but not in benign oral lesions.

Autologous Hematopoietic Stem Cell Transplantation for Childhood Autoimmune Disease

Autologous and allogeneic hematopoietic stem cell transplantation (HSCT) can be used in the management of patients with autoimmune disorders. Experience gained in adults has helped to better define the conditioning regimens required and appropriate selection of patients who are most likely to benefit from autologous HSCT. The field has been shifting toward the use of safer and less intense nonmyeloablative regimens used earlier in the disease course before patients accumulate extensive irreversible organ damage. This article reviews the experience of using autologous HSCT in treating the most common childhood autoimmune and rheumatic diseases, primarily juvenile idiopathic arthritis, systemic lupus erythematosus, and diabetes mellitus.

Factors involved in the T helper type 1 and type 2 cell commitment and osteoclast regulation in inflammatory apical diseases

Periapical chronic lesion formation involves activation of the immune response and alveolar bone resorption around the tooth apex. However, the overall roles of T helper type 1 (Th1), Th2, and T-regulatory cell (Treg) responses and osteoclast regulatory factors in periapical cysts and granulomas have not been fully determined. This study aimed to investigate whether different forms of apical periodontitis, namely cysts and granulomas, show different balances of Th1, Th2 regulators, Treg markers, and factors involved in osteoclast chemotaxis and activation. Gene expression of these factors was assessed using quantitative real-time polymerase chain reaction, in samples obtained from healthy gingiva (n = 8), periapical granulomas (n = 20), and cysts (n = 10). Periapical cysts exhibited a greater expression of GATA-3, while a greater expression of T-bet, Foxp3, and interleukin-10 (IL-10) was seen in granulomas. The expression of interferon-gamma, IL-4, and transforming growth factor-beta was similar in both lesions. Regarding osteoclastic factors, while the expression of SDF-1 alpha/CXCL12 and CCR1 was higher in cysts, the expression of RANKL was significantly higher in granulomas. Both lesions exhibited similar expression of CXCR4, CK beta 8/CCL23, and osteoprotegerin, which were significantly higher than in control. Our results showed a predominance of osteoclast activity in granulomas that was correlated with the Th1 response. The concomitant expression of Treg cell markers suggests a possible suppression of the Th1 response in granulomas. On the other hand, in cysts the Th2 activity is augmented. The mechanisms of periradicular lesion development are still not fully understood but the imbalance of immune and osteoclastic cell activity in cysts and granulomas seems to be critically regulated by Treg cells.

Regulation of type 17 helper T-cell function by nitric oxide during inflammation

Type 17 helper T (Th17) cells are implicated in the pathogenesis many of human autoimmune diseases. Development of Th17 can be enhanced by the activation of aryl hydrocarbon receptor (AHR) whose ligands include the environmental pollutant dioxin, potentially linking environmental factors to the increased prevalence of autoimmune disease. We report here that nitric oxide (NO) can suppress the proliferation and function of polarized murine and human Th17 cells. NO also inhibits AHR expression in Th17 cells and the downstream events of AHR activation, including IL-22, IL-23 receptor, and Cyp1a1. Conversely, NO did not affect the polarization of Th17 cells from mice deficient in AHR. Furthermore, mice lacking inducible nitric oxide synthase (Nos2(-/-)) developed more severe experimental autoimmune encephalomyelitis than WT mice, with elevated AHR expression, increased IL-17A, and IL-22 synthesis. NO may therefore represent an important endogenous regulator to prevent overexpansion of Th17 cells and control of autoimmune diseases caused by environmental pollutants.

Involvement of LTB4 in zymosan-induced joint nociception in mice: participation of neutrophils and PGE(2)

Leukotriene B-4 (LTB4) mediates different inflammatory events such as neutrophil migration and pain. The present study addressed the mechanisms of LTB4-mediated joint inflammation-induced hypernociception. It was observed that zymosan-induced articular hypernociception and neutrophil migration were reduced dose-dependently by the pretreatment with MK886 (1-9 mg/kg; LT synthesis inhibitor) as well as in 5-lypoxygenase-deficient mice (5LO(-/-)) or by the selective antagonist of the LTB4 receptor (CP105696; 3 mg/kg). Histological analysis showed reduced zymosan-induced articular inflammatory damage in 5LO(-/-) mice. The hypernociceptive role of LTB4 was confirmed further by the demonstration that joint injection of LTB4 induces a dose (8.3, 25, and 75 ng)-dependent articular hypernociception. Furthermore, zymosan induced an increase in joint LTB4 production. Investigating the mechanism underlying LTB4 mediation of zymosan-induced hypernociception, LTB4-induced hypernociception was reduced by indomethacin (5 mg/kg), MK886 (3 mg/kg), celecoxib (10 mg/kg), antineutrophil antibody (100 mu g, two doses), and fucoidan (20 mg/kg) treatments as well as in 5LO(-/-) mice. The production of LTB4 induced by zymosan in the joint was reduced by the pretreatment with fucoidan or antineutrophil antibody as well as the production of PGE(2) induced by LTB4. Therefore, besides reinforcing the role of endogenous LTB4 as an important mediator of inflamed joint hypernociception, these results also suggested that the mechanism of LTB4-induced articular hypernociception depends on prostanoid and neutrophil recruitment. Furthermore, the results also demonstrated clearly that LTB4-induced hypernociception depends on the additional release of endogenous LTs. Concluding, targeting LTB4 synthesis/action might constitute useful therapeutic approaches to inhibit articular inflammatory hypernociception.

Cysteinyl-leukotriene type 1 receptors transduce a critical signal for the up-regulation of eosinophilopoiesis by interleukin-13 and eotaxin in murine bone marrow

IL-13 and eotaxin play important, inter-related roles in asthma models. In the lungs, CysLT, produced by the 5-LO-LTC4S pathway, mediate some local responses to IL-13 and eotaxin; in bone marrow, CysLT enhance IL-5-dependent eosinophil differentiation. We examined the effects of IL-13 and eotaxin on eosinophil differentiation. Semi-solid or liquid cultures were established from murine bone marrow with GM-CSF or IL-5, respectively, and the effects of IL-13, eotaxin, or CysLT on eosinophil colony formation and on eosinophil differentiation in liquid culture were evaluated, in the absence or presence of: a) the 5-LO inhibitor zileuton, the FLAP inhibitor MK886, or the CysLT1R antagonists, montelukast and MK571; b) mutations that inactivate 5-LO, LTC4S, or CysLT1R; and c) neutralizing mAb against eotaxin and its CCR3 receptor. Both cytokines enhanced GM-CSF-dependent eosinophil colony formation and IL-5-stimulated eosinophil differentiation. Although IL-13 did not induce eotaxin production, its effects were abolished by anti-eotaxin and anti-CCR3 antibodies, suggesting up-regulation by IL-13 of responses to endogenous eotaxin. Anti-CCR3 blocked eotaxin completely. The effects of both cytokines were prevented by zileuton, MK886, montelukast, and MK571, as well as by inactivation of the genes coding for 5-LO, LTC4S, and CysLT1R. In the absence of either cytokine, these treatments or mutations had no effect. These findings provide evidence for: a) a novel role of eotaxin and IL-13 in regulating eosinophilopoiesis; and b) a role for CysLTRs in bone marrow cells in transducing cytokine regulatory signals. J. Leukoc. Biol. 87: 885-893; 2010.

The `club` cell and behavioural and physiological responses to chemical alarm cues in the Nile tilapia

The alarm response to skin extract has been well documented in fish. In response to skin extract, there is a decline in both locomotion activity and aggressive interactions. Our observation herein of these responses in the cichlid Nile tilapia, Oreochromis niloticus, confirmed the existence of the alarm response in this species. However, so far there has been a paucity of information on the autonomic correlates of this response. In this study, the ventilatory change in response to the chemical alarm cue was evaluated. This parameter was measured 4 min before and 4 min after exposure to 1 mL of either conspecific skin extract or distilled water (extract vehicle). Skin extract induced an increase in the ventilation rate, which suggested an anticipatory adjustment to potentially harmful stimuli. The chemical cue (alarm substance) also interfered with the prioritisation of responses to different environmental stimuli (stimuli filtering); this was suggested by the observation that the Nile tilapia declined to fight after exposure to a cue that indicates a risk of predation. Furthermore, histological analysis of the Nile tilapia skin revealed the presence of putative alarm substance-producing (club) cells.

A novel role for MNTB neuron dendrites in regulating action potential amplitude and cell excitability during repetitive firing

Principal cells of the medial nucleus of the trapezoid body (MNTB) are simple round neurons that receive a large excitatory synapse (the calyx of Held) and many small inhibitory synapses on the soma. Strangely, these neurons also possess one or two short tufted dendrites, whose function is unknown. Here we assess the role of these MNTB cell dendrites using patch-clamp recordings, imaging and immunohistochemistry techniques. Using outside-out patches and immunohistochemistry, we demonstrate the presence of dendritic Na(+) channels. Current-clamp recordings show that tetrodotoxin applied onto dendrites impairs action potential (AP) firing. Using Na(+) imaging, we show that the dendrite may serve to maintain AP amplitudes during high-frequency firing, as Na(+) clearance in dendritic compartments is faster than axonal compartments. Prolonged high-frequency firing can diminish Na(+) gradients in the axon while the dendritic gradient remains closer to resting conditions; therefore, the dendrite can provide additional inward current during prolonged firing. Using electron microscopy, we demonstrate that there are small excitatory synaptic boutons on dendrites. Multi-compartment MNTB cell simulations show that, with an active dendrite, dendritic excitatory postsynaptic currents (EPSCs) elicit delayed APs compared with calyceal EPSCs. Together with high- and low-threshold voltage-gated K(+) currents, we suggest that the function of the MNTB dendrite is to improve high-fidelity firing, and our modelling results indicate that an active dendrite could contribute to a `dual` firing mode for MNTB cells (an instantaneous response to calyceal inputs and a delayed response to non-calyceal dendritic excitatory postsynaptic potentials).

Brood cell size of Apis mellifera modifies the reproductive behavior of Varroa destructor

We undertook a field study to determine whether comb cell size affects the reproductive behavior of Varroa destructor under natural conditions. We examined the effect of brood cell width on the reproductive behavior of V. destructor in honey bee colonies, under natural conditions. Drone and worker brood combs were sampled from 11 colonies of Apis mellifera. A Pearson correlation test and a Tukey test were used to determine whether mite reproduction rate varied with brood cell width. Generalized additive model analysis showed that infestation rate increased positively and linearly with the width of worker and drone cells. The reproduction rate for viable mother mites was 0.96 viable female descendants per original invading female. No significant correlation was observed between brood cell width and number of offspring of V. destructor. Infertile mother mites were more frequent in narrower brood cells.

Association of drug metabolism gene polymorphisms with toxicities, graft-versus-host disease and survival after HLA-identical sibling hematopoietic stem cell transplantation for patients with leukemia

Individual differences in drug efficacy or toxicity can be influenced by genetic factors. We investigated whether polymorphisms of pharmacogenes that interfere with metabolism of drugs used in conditioning regimen and graft-versus-host disease (GvHD) prophylaxis could be associated with outcomes after HLA-identical hematopoietic stem cell transplantation (HSCT). Pharmacogenes and their polymorphisms were studied in 107 donors and patients with leukemia receiving HSCT. Candidate genes were: P450 cytochrome family (CYP2B6), glutathione-S-transferase family (GST), multidrug-resistance gene, methylenetetrahydrofolate reductase (MTHFR) and vitamin D receptor (VDR). The end points studied were oral mucositis (OM), hemorrhagic cystitis (HC), toxicity and venoocclusive disease of the liver (VOD), GvHD, transplantation-related mortality (TRM) and survival. Multivariate analyses, using death as a competing event, were performed adjusting for clinical factors. Among other clinical and genetic factors, polymorphisms of CYP2B6 genes that interfere with cyclophosphamide metabolism were associated with OM (recipient CYP2B6*4; P=0.0067), HC (recipient CYP2B6*2; P=0.03) and VOD (donor CYP2B6*6; P=0.03). Recipient MTHFR polymorphisms (C677T) were associated with acute GvHD (P=0.03), and recipient VDR TaqI with TRM and overall survival (P=0.006 and P=0.04, respectively). Genetic factors that interfere with drug metabolisms are associated with treatment-related toxicities, GvHD and survival after HLA-identical HSCT in patients with leukemia and should be investigated prospectively.

TAGLN expression is deregulated in endometriosis and may be involved in cell invasion, migration, and differentiation

We found an increased expression of the TAGLN gene in endometriotic lesions compared with the eutopic endometrium of the same patients by real-time polymerase chain reaction. It is possible that this deregulation contributes to the development and maintenance of endometriosis by being involved in the pathways of organization of cytoskeletal architecture. (Fertil Steril (R) 2011;96:700-3. (C)2011 by American Society for Reproductive Medicine.)

Ethinylestradiol and estradiol have different effects on oxidative stress and nitric oxide synthesis in human endothelial cell cultures

Study objective: To compare the effects of ethinylestradiol (EE) and 17 beta-estradiol (E(2)) on nitric oxide (NO) production and protection against oxidative stress in human endothelial cell cultures. Design: Experimental study. Settings: Research laboratory. Material: Human ECV304 endothelial cell cultures. Intervention(s): The NO synthesis was determined by flow cytometry, and oxidative stress was determined by a cell viability assay, after exposure to hydrogen peroxide (H(2)O(2)) and stimulation of endothelial cells with EE at concentrations similar to those of a contraceptive containing 30 mu g EE. Main Outcome Measure(s): The effects of EE were compared with those of E(2) at concentrations similar to those occurring during the follicular phase. Result(s): Ethinylestradiol did not increase NO synthesis and did not protect cells against oxidative stress. The viability of the cells incubated with E(2) in combination with H(2)O(2) was greater than the viability obtained with H(2)O(2) only or with H(2)O(2) in combination with EE. The cells stimulated with E(2) presented a significant increase in NO production compared with control. Conclusion(s): In contrast to the effects of E(2), EE did not protect human ECV304 endothelial cells against oxidative stress and did not increase their production of NO. (Fertil Steril (R) 2010; 94: 1578-82. (C) 2010 by American Society for Reproductive Medicine.)

Increased circulating cell-free hemoglobin levels reduce nitric oxide bioavailability in preeclampsia

Contrasting with increased nitric oxide (NO) formation during healthy pregnancy, reduced NO bioavailability plays a role in preeclampsia. However, no study has examined whether increased NO consumption by enhanced circulating levels of cell-free hemoglobin plays a role in preeclampsia. We studied 82 pregnant women (38 healthy pregnant and 44 with preeclampsia). To assess NO bioavailability, we measured plasma and whole blood nitrite concentrations using an ozone-based chemiluminescence assay. Plasma ceruloplasmin concentrations and plasma NO consumption (pNOc) were assessed and plasma hemoglobin (pHb) concentrations were measured with a commercial immunoassay. We found lower whole blood and plasma nitrite concentrations in preeclamptic patients (-48 and -39%, respectively; both P<0.05) compared with healthy pregnant women. Plasma samples from preeclamptic women consumed 63% more NO (P=0.003) and had 53% higher pHb and 10% higher ceruloplasmin levels than those found in healthy pregnant women (P<0.01). We found significant positive correlations between pHb and pNOc (r=0.61; P<0.0001), negative correlations between pNOc and whole blood or plasma nitrite concentrations (P=0.02; r=-0.32 and P=0.01: r=-0.34, respectively), and negative correlations between pHb and whole blood or plasma nitrite concentrations (P=0.03; r=-0.36 and P=0.01: r=-0.38, respectively). These findings suggest that increased pHb levels lead to increased NO consumption and lower NO bioavailability in preeclamptic compared with healthy pregnant women. (C) 2010 Elsevier Inc. All rights reserved.