Malignancy-related 67kDa laminin receptor in adenoid cystic carcinoma. Effect on migration and beta-catenin expression

Adenoid cystic carcinoma is a malignant salivary gland neoplasm with recurrence and metastasis. We studied the expression of a malignancy-related non-integrin laminin receptor, the 67LR, in this neoplasm. Immunohistochemistry showed 67LR in adenoid cystic carcinoma. This receptor binds a sequence of laminin β1 chain, the YIGSR peptide. We studied the effect of 67LR and YIGSR in cells (CAC2) from adenoid cystic carcinoma. Three-dimensional cultures of cells embedded into either laminin-111 gel (controls) or YIGSR-enriched laminin-111 (treated) were prepared and studied by light microscopy. CAC2 cells treated with YIGSR appeared fibroblast-like, while control cells were epithelioid. Blockage of 67LR by antibody abolished YIGSR effect in three-dimensional cultures. We analysed the relevance of 67LR and YIGSR on β-catenin expression in CAC2 cells. Immunofluorescence and immunoblot showed that YIGSR decreased β-catenin, while blockage of 67LR restored the presence of this molecule. The 67LR and YIGSR induced fibroblast-like morphology in CAC2 cells, with disruption of cell–cell contacts and decrease of β-catenin. These features resemble epithelial–mesenchymal transition (EMT). EMT also increases cell migration. In monolayer assays YIGSR increased migration of CAC2 cells. We conclude that 67LR and YIGSR are involved in epithelial–mesenchymal transition, modulation of β-catenin expression, and migratory activity of CAC2 cells.     

The effect of a reconstituted basement membrane (Matrigel) on a human salivary gland myoepithelioma cell line

We have already demonstrated that a reconstituted basement membrane (Matrigel) is a key modulator of morphogenetic changes and cytodifferentiation of pleomorphic adenoma cells in culture. Myoepithelioma is considered to be a neoplasm closely related to pleomorphic adenoma and should experience similar induction processes. Thus, the aim of this study was to investigate whether Matrigel would influence myoepithelioma cells. We used a cell line derived from a human salivary gland plasmacytoid myoepithelioma (M1 cells) grown in a three-dimensional preparation of Matrigel. Phenotype differences were assessed using conventional light microscopy technique (haematoxylin and eosin) and phase and differential interference contrast (Nomarski). Immunofluorescence was carried out to detect smooth-muscle actin, laminin and type-IV collagen. M1 cells exhibited all proteins studied, showing a myoepithelial differentiation. M1 cells grown inside Matrigel presented morphological changes and changes in smooth-muscle actin status. By growing M1 cells inside Matrigel, it was possible to reproduce the tumour architecture with no duct-like structures. Based on our findings, we suggest that myoepithelioma would be derived from a cell with a commitment to myoepithelial differentiation. We also suggest that the mechanical properties of the matrix environment will likely regulate smooth-muscle actin expression in myoepithelioma.     

In vivo dynamics of T cell activation,proliferation, and death in HIV-1 infection: why are CD4+ but not CD8+ T cells depleted?

Deuterated glucose labeling was used to measure the in vivo turnover of T lymphocytes. A realistic T cell kinetic model, with populations of resting and activated T cells, was fitted to d-glucose labeling data from healthy and HIV-1-infected individuals before and after antiretroviral treatment. Our analysis highlights why HIV-1 infection, which increases the fraction of both CD4(+) and CD8(+) T lymphocytes that are proliferating (Ki67(+)), leads to CD4 but not CD8 depletion. We find that HIV-1 infection tends to increase the rates of death and proliferation of activated CD4(+) T cells, and to increase the rate at which resting CD4 T cells become activated, but does not increase the fraction of activated CD4(+) T cells, consistent with their preferential loss in HIV-1-infected individuals. In contrast, HIV-1 infection does not lead to an increase in proliferation or death rates of activated CD8(+) T cells, but did increase the fraction of activated CD8(+) T cells, consistent with these cells remaining in an activated state longer and undergoing more rounds of proliferation than CD4(+) T cells. Our results also explain why telomeres shorten in CD8(+) cells, but not in CD4(+) cells of HIV-1-infected patients, compared with age-matched controls.     

Mobility therapy and central or peripheral catheter-related adverse events in an ICU in Brazil

OBJECTIVE:

To determine whether mobility therapy is associated with central or peripheral catheter-related adverse events in critically ill patients in an ICU in Brazil.

METHODS:

A retrospective analysis of the daily medical records of patients admitted to the Clinical Emergency ICU of the University of São Paulo School of Medicine Hospital das Clínicas Central Institute between December of 2009 and April of 2011. In addition to the demographic and clinical characteristics of the patients, we collected data related to central venous catheters (CVCs), hemodialysis (HD) catheters and indwelling arterial catheters (IACs): insertion site; number of catheter days; and types of adverse events. We also characterized the mobility therapy provided.

RESULTS:

Among the 275 patients evaluated, CVCs were used in 49%, HD catheters were used in 26%, and IACs were used in 29%. A total of 1,268 mobility therapy sessions were provided to patients while they had a catheter in place. Catheter-related adverse events occurred in 20 patients (a total of 22 adverse events): 32%, infection; 32%, obstruction; and 32%, accidental dislodgement. We found that mobility therapy was not significantly associated with any catheter-related adverse event, regardless of the type of catheter employed: CVC-OR = 0.8; 95% CI: 0.7-1.0; p = 0.14; HD catheter-OR = 1.04; 95% CI: 0.89-1.21; p = 0.56; or IAC-OR = 1.74; 95% CI: 0.94-3.23; p = 0.07.

CONCLUSIONS:

In critically ill patients, mobility therapy is not associated with the incidence of adverse events involving CVCs, HD catheters, or IACs.     

Role of endogenous angiotensin II on glutamatergic actions in the rostral ventrolateral medulla in Goldblatt hypertensive rats

In this study, we investigated the cardiovascular responses mediated by rostral ventrolateral medulla neurons (RVLM) in the Goldblatt hypertension model (2K-1C) treated or not treated with captopril. The actions of glutamate into the RVLM were tested, injecting glutamate (0.1 mol/L, 100 nL) and its antagonist kynurenic acid (0.02 mol/L, 100 nL). Glycine (0.5 mol/L, 100 nL) was also microinjected. Experiments were performed in male Wistar rats (weight, 250 to 300 g); 5 groups were studied: (1) 2K-1C nontreated (H, n=6); (2) 2K-1C treated with captopril, 10 mg/kg per day (Ht10, n=10); (3) 2K-1C treated with captopril, 50 mg/kg per day (Ht50, n=7); (4) control normotensive rats (N, n=7); and (5) normotensive rats treated with captopril, 50 mg/kg per day (Nt50, n=8). All experiments in 2K-1C were performed 6 weeks after renal surgery; captopril treatment lasted for the last 2 weeks. In urethane-anesthetized rats (1.2 g/kg IV), bilateral microinjection of glycine into the RVLM caused a depressor response; there was no difference between groups in relation to the change of variation (N: 54+/-2; H: 46+/-12; Ht10: 50+/-3, and Ht50: 42+/-7 mm Hg). Only in the H group, kynurenic acid microinjection into the RVLM caused a depressor response (H: 158+/-8 to 132+/-8 mm Hg). Glutamate response was larger in hypertensive than in normotensive rats (N: 38+/-2.6 and H: 55+/-6); no difference was observed between hypertensive groups. The data suggest that glutamate acts tonically to drive the RVLM in 2K-1C rats, and this action is modulated by endogenous angiotensin II. The increase in the glutamate actions within the RVLM may contribute to the pathogenesis of renovascular hypertension.     

Hepatitis C virus (HCV) and human immunodeficiency virus (HIV) dynamics during HCV treatment in HCV/HIV coinfection

We studied hepatitis C virus (HCV) and human immunodeficiency virus (HIV) dynamics in 10 coinfected subjects in a trial of pegylated interferon-alpha2a (PEG-IFN) alone or combined with ribavirin (RBV), compared with IFN plus RBV for the treatment of HCV. Five subjects, 4 of whom were treated with PEG-IFN, achieved a sustained virological response, although it was delayed by >/=1 week in 3 subjects. The median treatment efficacy in blocking virion production was 99.7% in the PEG-IFN group and 60% with standard IFN. In 2 patients with detectable HIV loads before starting HCV study drugs, we observed a 1-log decrease in HIV RNA load. The estimated HCV virion half-life was longer in the HIV-coinfected subjects, which suggests that coinfection may contribute to a slower clearance of HCV. Although the early viral kinetics of coinfected subjects treated with PEG-IFN or IFN differ from those of singly infected subjects, the treatment response seems unaffected.     

Expression of acute-phase cytokines,surfactant proteins,and epithelial apoptosis in small airways of human acute respiratory distress syndrome

Purpose

Recent studies suggest a role for distal airway injury in acute respiratory distress syndrome (ARDS). The epithelium lining the small airways secretes a large number of molecules such as surfactant components and inflammatory mediators. There is little information on how these small airway secretory functions are altered in ARDS.

Materials and Methods

We studied the lungs of 31 patients with ARDS (Pao₂/fraction of inspired oxygen ≤ 200, 45 ± 14 years, 16 men) and 11 controls (52 ± 16 years, 7 men) submitted to autopsy and quantified the expression of interleukin (IL) 6, IL-8, surfactant proteins (SP) A and SP-B in the epithelium of small airways using immunohistochemistry and image analysis. In addition, an index of airway epithelial apoptosis was determined by the terminal deoxynucleotidyl transferase-mediated deoxyuridine-triphosphatase nick-end labeling assay, caspase 3, and Fas/Fas ligand expression. The density of inflammatory cells expressing IL-6 and IL-8 within the small airway walls was also quantified.

Results

Acute respiratory distress syndrome airways showed an increase in the epithelial expression of IL-8 (P = .006) and an increased density of inflammatory cells expressing IL-6 (P = .004) and IL-8 (P < .001) compared with controls. There were no differences in SP-A and SP-B epithelium expression or in epithelial apoptosis index between ARDS and controls.

Conclusion

Distal airways are involved in ARDS lung inflammation and show a high expression of proinflammatory interleukins in both airway epithelial and inflammatory cells. Apoptosis may not be a major mechanism of airway epithelial cell death in ARDS.