Defective plasmacytoid dendritic cell-NK cell cross-talk in HIV infection

HIV viremia is associated with a wide range of immune dysfunctions that contribute to the immunocompromised state. HIV viremia has been shown to have a broad effect on several immune cell types and/or their interactions that are vital for mounting an effective immune response. In this study, we investigated the integrity of plasmacytoid dendritic cell (pDC)-NK cell interactions among HIV viremic, aviremic, and seronegative individuals. We describe a critical defect in the ability of pDCs from HIV-infected individuals to secrete IFN-alpha and TNF and subsequently activate NK cells. We also describe an inherent defect on NK cells from HIV-infected individuals to respond to pDC-secreted cytokines. Furthermore, we were able to demonstrate a direct effect of HIV trimeric gp120 on NK cells in vitro similar to that described ex vivo. Finally, we were able to establish that the HIV gp120-mediated suppressive effect on NK cells was a result of its binding to the integrin alpha(4)beta(7) expressed on NK cells. These findings suggest a novel mechanism by which HIV is capable of suppressing an innate immune function in infected individuals.

Diabetes mellitus after living donor liver transplantation: data from mainland China

Most reported data on posttransplantation diabetes mellitus (PTDM) are from Western countries with patients who underwent deceased donor liver transplantation. A retrospective study was performed to assess the prevalence and predictive factors of PTDM in the context of living donor liver transplantation (LDLT) in the Chinese population using the definition of PTDM proposed in 2003 by the World Health Organization and the American Diabetes Association. The prevalence of DM after LDLT in our study was 25% (21/84), and the incidence of PTDM was 14.9% (11/74) with 64% of cases diagnosed within 3 months after LDLT; 9.5% were observed to show impaired fasting glucose postoperatively. Multivariate analysis identified body mass index >or= 25 kg/m(2) before LDLT as the only independent risk factor for developing PTDM. Only one patient was operated for hepatitis C virus (HCV) infection. Hepatitis B virus (HBV)-related diseases were common in our study population, accounting for 78.6% of all patients. Both HCV and HBV infection status were not independent risk factors for developing PTDM. In addition, a greater tacrolimus trough blood level in the PTDM group versus no-DM group was observed at 3 months post-LDLT (11.03 ng/mL vs 4.87 ng/mL). The mean tacrolimus dose was not significantly different between the two groups. In conclusion, PTDM was prevalent among Chinese LDLT recipients.

Effects of losartan on fibrinolytic parameters and von Willebrand factor in Chinese subjects with hypertension: a comparative study versus atenolol

To compare the effects of losartan and atenolol on plasma fibrinolytic parameters and von Willebrand factor (vWF), Chinese subjects with mild-to-moderate hypertension were randomized to receive losartan (50 mg/day; n = 30) or atenolol (50 mg/day; n = 30) for 8 weeks. If target blood pressure (< 140/90 mmHg) was not achieved at week 4, hydrochlorothiazide (12.5 mg/day) was also administered. Plasma levels of tissue plasminogen activator (tPA), plasminogen activator inhibitor-1 (PAI-1) and vWF were determined at baseline and after treatment. Between-group baseline characteristics and blood pressure decrease were comparable. Losartan significantly reduced plasma PAI-1 and vWF and PAI-1/tPA ratio. Atenolol significantly increased plasma tPA, but PAI-1, vWF and PAI-1/tPA ratio were unchanged. In conclusion, losartan, but not atenolol improved the fibrinolytic system and reduced plasma vWF levels in Chinese hypertensives.

Preparation and analysis of 1-chloronaphthalene for highly refractive electrowetting optics

High-index oils are critical to the performance of optical electrowetting devices, such as lenses, prisms, and retroreflectors. Herein, the preparation and electrowetting analysis of 1-chloronaphthalene are reported. When 1-chloronaphthalene is mixed with small amounts of an alkane, the following properties can be achieved: refractive index > 1.60, viscosity < 5 cP for rapid switching, operation at <10 V, and +/-45 degrees of electrowetting modulation around the condition for a flat meniscus (90 degrees ).

A novel treatment strategy targeting polo-like kinase 1 in hematological malignancies

Polo-like kinase1 (PLK1) belongs to the family of serine/threonine kinases and plays an important role in centrosome maturation, bipolar spindle formation, and cytokinesis during mitosis. We found in this study that PLK1 was aberrantly highly expressed in a variety of human leukemia cell lines (n=20), as well as, freshly isolated leukemia cells from individuals with acute myelogenous leukemia (n=50) and acute lymphoblastic leukemia (n=15) compared with bone marrow mononuclear cells from healthy volunteers (n=13) (acute myelogenous leukemia, P=0.016; acute lymphoblastic leukemia, P=0.008), as measured by real-time RT-PCR. Downregulation of PLK1 by a small interfering RNA in NB4 acute myelogenous leukemia cells inhibited their proliferation. GW843682X is a novel selective PLK1 inhibitor. The compound-induced growth inhibition, caused accumulation of cells in the G2/M phase of the cell cycle and mediated apoptosis of human leukemia cells. Pre-treatment of cells with the caspase inhibitor Z-VAD-FMK attenuated the action of GW843682X in leukemia cells, indicating the involvement of the caspase pathway in the PLK1 inhibitor-mediated apoptosis. Furthermore, we found that the PLK1 inhibitor synergistically potentiated the growth inhibition and apoptosis of leukemia cells when combined with tubulin-depolymerizing agent vincristine. Taken together, targeting PLK1 may be a promising treatment strategy for individuals with leukemia.

Towards a quantitative framework for the prediction of DDIs arising from cytochrome P450 induction

Although CYP induction is not generally considered to be as clinically relevant as CYP inhibition, there are important examples where induction has caused both therapeutic failure, due to insufficient exposure to parent drug, and toxicity, mediated by increased formation of reactive metabolites. Furthermore, while there has been considerable progress in the extrapolation of in vitro data to predict the in vivo consequences of enzyme inhibition, less attention has been given to the quantitative impact of enzyme induction as a mechanism of drug-drug interaction (DDI) and as a component of compound selection and early drug development. We discuss current approaches in the context of a mechanistic framework for the prediction of the extent and time-course of enzyme induction in vivo based on in vitro experimentation. Factors influencing the extent of DDI due to CYP induction are summarised, and areas deficient in information that would allow more accurate prediction within target populations are highlighted.

The association between MIF-173 G>C polymorphism and prostate cancer in southern Chinese

BACKGROUND AND OBJECTIVES

Accumulating epidemiological and molecular evidence suggests that inflammation is an important component in the etiology of PCa. Macrophage migration inhibitory factor (MIF) plays an important role in the pro- and anti-inflammatory response to infection. This study is aimed at investigating the potential association between MIF-173 G>C polymorphism, Gleason score, clinical stage, and prostate-specific antigen (PSA) value with respect to PCa incidence among the Han nationality in Southern China.

METHODS

Genotyping was performed by using tetraprimer polymerase chain reaction (PCR) on 259 PCa patients and 301 cancer-free controls.

RESULTS

We found that the MIF-173*C variant allele was significantly associated with an increased risk of PCa [adjusted odd ratio (OR) = 2.99, 95% confident interval (CI): 1.94-4.60] and higher Gleason scores from the PCa subjects (adjusted OR = 10.72, 95% CI: 5.35-21.49). In addition, we noted that the MIF -173*C variant allele was related to higher clinical stages and PSA values in PCa patients (adjusted OR = 15.68, 95% CI: 7.40-33.23; adjusted OR = 4.37, 95% CI: 2.41-7.92, respectively).

CONCLUSION

Our data suggest that MIF-173 polymorphisms may be associated with a higher incidence of prostate cancer compared to controls, and appears to be associated with higher Gleason scores, higher clinical stages, and PSA values in those with prostate cancer.

Up-regulation of cellular FLICE-inhibitory protein in peripheral blood B lymphocytes in patients with systemic lupus erythematosus is associated with clinical characteristics

BACKGROUND

Systemic lupus erythematosus (SLE) is an autoimmune disease which is involved in T- and B-lymphocyte-mediated autoimmunity. Apoptosis contributes to the maintenance of lymphocytes homeostasis and the deletion of autoreactive cells in SLE. Although there is evidence that cellular FLICE-inhibitory protein (c-FLIP), an antiapoptosis protein, is increased in human lupus T cells to keep them from apoptosis, but the expression of apoptosis-regulatory protein c-FLIP in SLE B lymphocytes remains unknown.

AIMS

To study the expression of c-FLIP in peripheral blood B lymphocytes in SLE patients and to investigate the relationship among the expression of c-FLIP in peripheral blood B lymphocytes in SLE patients, clinical manifestation and the levels of interleukin-4 (IL-4) and IL-10.

METHODS

In this study, we detected the expression of c-FLIP in peripheral blood B lymphocytes in SLE patients by flow cytometry and the levels of IL-4 and IL-10 in SLE serum samples by enzyme-linked immunosorbent assay and analysed their relationship with clinical characteristics.

RESULTS

We observed a significantly higher percentage of c-FLIP in peripheral B cells in SLE patients with active disease when compared to inactive ones and healthy controls. And the expression of c-FLIP in lupus peripheral B cells showed positive correlations with SLEDAI, erythrocyte sedimentation rate, C-reactive protein, antinucleosome antibody titre, IL-4, and IL-10, and negative correlation with white blood cell count. Patients with lupus nephritis had higher levels of c-FLIP in peripheral B cells than patients without lupus nephritis.

CONCLUSION

Our data show that overexpression of c-FLIP is relevant to the activity and severity of SLE. Its overexpression might play a role in preventing B cell from apoptosis in SLE. The cause of c-FLIP overexpression may be due to the increase of IL-4 and IL-10 levels in SLE patients.

Sensitive determination of protein based on the fluorescence enhancement effect of terbium (III)-epinephrine-protein-sodium dodecylsulfate system

It was found that the fluorescence of Tb(3+)-epinephrine (E) complex can be enhanced by both bovine serum albumin (BSA) and sodium dodecylsulfate (SDS), and stabilized by ascorbic acid (AA). It is considered that the fluorescence enhancement of the Tb(3+)-E-BSA-AA-SDS system originates not only from the hydrophobic microenvironment provided by BSA-SDS, but also from the energy transfer from BSA to Tb(3+) in this system. Therefore, a new fluorescence method for the determination of protein concentrations as low as 1.3 x 10(-9) g mL(-1) BSA is established using Tb(3+)-epinephrine complex as probe. The method has been applied for the determination of BSA and human serum albumin in actual samples, and the results obtained are satisfactory. Compared with other fluorescence methods, this method is simpler and more sensitive for the determination of protein. The mechanism of the fluorescence enhancement of the system is studied in detail.

Significance of phosphatase and tensin homologue (PTEN), O(6)-methylguanine-DNA methyltransferase (MGMT), and DNA-dependent protein kinase catalytic subunit (DNA-PKcs) protein expression in gynaecomastia

This study was designed to investigate the pathogenesis of gynaecomastia by measuring phosphatase and tensin homologue (PTEN), O(6)-methylguanine-DNA methyltransferase (MGMT) and DNA-dependent protein kinase catalytic subunit (DNA-PKcs) protein in breast tissue specimens from 68 patients with gynaecomastia and 24 normal male controls using immunohistochemical staining. The gynaecomastia cases were divided into three different histological types: florid, intermediate and fibrous. The PTEN, MGMT and DNA-PKcs proteins were detected in both gynaecomastia and normal breast tissue, but the levels of immunohistochemical staining of each protein were significantly lower in gynaecomastia breast tissue than in normal breast tissue. There were also significant differences in the levels of immunohistochemical staining for the three proteins according to gynaecomastia histological type. These results suggest that abnormally low levels of PTEN, MGMT and DNA-PKcs protein in gynaecomastia breast tissue may play a role in the development of gynaecomastia. Further research is required to elucidate fully their individual roles in the pathophysiology of gynaecomastia.

SINGLE UV EXCITATION OF HOECHST 33342 AND PROPIDIUM IODIDE FOR VIABILITY ASSESSMENT OF RHESUS MONKEY SPERMATOZOA USING FLOW CYTOMETRY

Many fluorescent probes excited by visible light have been used to assess sperm quality by flow cytometry. Developing a viability evaluation method using UV excited stains would be useful for multiparameter analysis of sperm function. This investigation was conducted to determine the efficacy of Hoechst 33342 (H342) and propidium iodide (PI) dual staining for evaluating rhesus monkey sperm viability through use of flow cytometry and excited by a single UV laser. The results showed that the live cells stained only with H342 strongly correlated with expected sperm viability, and flow cytometric analyses were highly correlated with fluorescence microscopic observation. Using H342/PI/SYBR-14 triple staining method, it was found that the live/dead sperm distributions were completely concordant in both H342/PI and SYBR-14/PI assays. In addition, this dual staining was extended with fluorescein isothiocyanate-conjugated peanut agglutinin (FITC-PNA) to simultaneously analyze viability and acrosome integrity of sperm cryopreserved using two different extenders, TTE and TEST, and indicated that TTE offered better preservation of plasma and acrosome integrity than TEST. Therefore, the H342/PI dual staining provides an accurate technique for evaluating viability of rhesus monkey sperm and should be valuable for multiparameter flow cytometric analysis of sperm function.

Cyclin D1 promotes anchorage-independent cell survival by inhibiting FOXO-mediated anoikis

O-class forkhead box (FOXO) transcription factors are critical regulators of diverse cellular processes, including apoptosis, cell-cycle arrest, DNA damage repair and oxidative stress resistance. Here, we show that FOXO1 and FOXO3a have an essential function in promoting cell detachment-induced anoikis, resistance to which is implicated in cancer development and metastasis. In contrast, the oncoprotein cyclin D1 inhibits anoikis. We further show that cyclin D1 interacts with FOXO proteins and impedes their transcriptional regulatory and anoikis-promoting functions. This effect of cyclin D1 requires its transcription repression domain but is independent of cyclin-dependent kinases CDK4 and CDK6. Moreover, we show that cancer-derived mutants of cyclin D1 are much more stable than wild-type cyclin D1 under anchorage-independent conditions and possess a greater antagonistic effect on FOXO-regulated anoikis and anchorage-independent growth of cancer cells. These data suggest that cyclin D1 may have a critical function in tumorigenesis and cancer metastasis by inhibiting the anoikis-promoting function of FOXO proteins.

Human immunodeficiency virus and hepatitis C infections induce distinct immunologic imprints in peripheral mononuclear cells

Coinfection with hepatitis C virus (HCV) is present in one-third of all human immunodeficiency virus (HIV)-infected individuals in the United States and is associated with rapid progression of liver fibrosis and poor response to pegylated interferon (IFN) and ribavirin. In this study we examined gene expression profiles in peripheral blood mononuclear cells (PBMCs) from different groups of individuals who are monoinfected or coinfected with HIV and HCV. Data showed that HIV and HCV viremia up-regulate genes associated with immune activation and immunoregulatory pathways. HCV viremia is also associated with abnormalities in all peripheral immune cells, suggesting a global effect of HCV on the immune system. Interferon-alpha-induced genes were expressed at a higher level in PBMCs from HIV-infected individuals. HCV and HIV infections leave distinct profiles or gene expression of immune activation in PBMCs. HIV viremia induces an immune activated state; by comparison, HCV infection induces immunoregulatory and proinflammatory pathways that may contribute to progression of liver fibrosis.

CONCLUSION

An aberrant type-I IFN response seen exclusively in HIV-infected individuals could be responsible for the poor therapeutic response experienced by HIV/HCV coinfected individuals receiving interferon-alpha-based current standard of care.

A non-uniform expansion mechanical safety model of the stent

Stents have a serial unstable structure that readily leads to non-uniform expansion. Non-uniform expansion in turn creates a stent safety problem. We explain how a stent may be simplified to a serial unstable structure, and present a method to calculate the non-uniform expansion of the stent on the basis of the serial unstable structure. We propose a safety criterion based on the expansion displacement instead of the strain, and explain that the parameter Rd, the ratio of the maximum displacement of the elements to normal displacement, is meaningful to assess the safety level of the stent. We also examine how laser cutting influences non-uniform expansion. The examples illustrate how to calculate the parameter Rd to assess non-uniform expansion of the stent, and demonstrate how the laser cutting offset and strengthening coefficient of the material influence the stent expansion behaviour. The methods are valuable for assessing stent safety due to non-uniform expansion.