Oral lactoferrin results in T cell-dependent tumor inhibition of head and neck squamous cell carcinoma in vivo.

PURPOSE: Human lactoferrin is a naturally occurring glycoprotein that inhibits cancer growth. Our purpose was to evaluate recombinant human lactoferrin as a chemotherapeutic agent against head and neck squamous cell carcinoma. EXPERIMENTAL DESIGN: Controlled experiments both in vitro and in the murine model evaluating both the effect and mechanism of lactoferrin on cancer growth. RESULTS: In both human and murine cell lines, lactoferrin induced dose-dependent growth inhibition. Using flow cytometric analysis, lactoferrin was shown to induce G(1)-G(0) growth arrest. This arrest seemed to be modulated by down-regulation of cyclin D1. In the in vitro model, luminex data revealed that lactoferrin inhibited cellular release of proinflammatory and prometastatic cytokines, including interleukin-8, interleukin-6, granulocyte macrophage colony-stimulating factor, and tumor necrosis factor-alpha. Lactoferrin up-regulated the cellular activation of nuclear factor-kappaB within 4 h of cellular exposure. In C3h/HeJ mice implanted with SCCVII tumors, orally delivered lactoferrin inhibited tumor growth by 75% compared with control mice. Immunohistochemical analysis of harvested tumors revealed up to 20-fold increases of lymphocytes within treated animals. When mice were depleted of CD3(+) cells, all lactoferrin-induced tumor inhibition was abrogated. CONCLUSION: We conclude that human recombinant lactoferrin can inhibit the growth of head and neck squamous cell carcinoma via direct cellular inhibition as well as systemically via immunomodulation. Our data support the study of human lactoferrin as an immunomodulatory compound with therapeutic potential.     

Development and validation of a risk scoring tool to predict respiratory syncytial virus hospitalization in premature infants born at 33 through 35 completed weeks of gestation

OBJECTIVE: The purpose of the study was to develop and validate a clinical instrument predicting the risk of respiratory syncytial virus (RSV)-associated hospitalization (RSV-H) in premature infants born at 33 through 35 completed weeks of gestation (33-35GA). DESIGN: An RSV risk scoring tool (RSV-RS) was developed by entering risk factors for RSV-H, determined in a Canadian prospective study, into a multiple logistic regression model. The scoring tool was then validated externally with data from a Spanish case-control study (FLIP). The Canadian cohort comprised 1758 RSV-positive infants born 33-35GA, of whom 66 (3.7%) had confirmed RSV-H. The FLIP data set comprised 186 (33.4%) RSV-H cases and 371 (66.7%) controls. METHOD: The primary outcome measure was RSV-H. The RSV-RS score was the sum of the weighted probabilities for each included risk factor multiplied by 100 and ranged from 0 to 100. Receiver operator characteristic curve analyses determined cutoff points to predict subjects at low, moderate, or high RSV-H risk. RESULTS: The RSV-RS included 7 risk factors and cutoff scores of 0-48, 49-64, and 65- 100 for low-, moderate-, and high-risk subjects, respectively. For the Canadian cohort, RSV-RS sensitivity in predicting RSV-H cases was 68.2%, with 71.9% specificity. With the FLIP data set, the RSV-RS had lower accuracy (61.3% sensitivity; 65.8% specificity) but showed significant positive association with increased risk for RSV-H. CONCLUSION: The RSV-RS accurately identified 33-35GA infants at increased risk for RSV-H in a Canadian cohort. External validation with Spanish case-control study data further confirmed that the scoring tool is appropriate for the estimation of RSV-H risk.     

Trends in consumption of calcium channel blockers in the Czech Republic during 1993-1999 and comparison with selected countries: drug utilization study

OBJECTIVE: To determine the patterns of consumption in calcium channel blockers (CCB) groups in the Czech Republic between 1992 and 1999 and make a comparison with selected countries. METHODS: This was part of a drug utilization study using WHO methodology [Anatomical Therapeutic Chemical classification/defined daily doses (ATC/DDD)]. The wholesale data collected by drug distributors were used. Utilization was calculated as the DDDs for 1000 inhabitants per day. In focus was the consumption of short-acting nifedipine. Comparison with wholesale data from Finland, Norway, Germany and Australia was made. RESULTS: There was a decreasing tendency to use short-acting nifedipine in the Czech Republic over the period 1993-1999. Four years after publication of warning evidence, short-acting nifedipine still accounted for 23% of all calcium channel blockers in our country. The abundance of second-generation CCBs increased from less than 1% in 1993 to 43% in 1999. The consumption of short-acting nifedipine in the Czech Republic and Germany is probably three times more frequent than in Nordic countries and Australia. CONCLUSIONS: Consumption of short-acting nifedipine in the Czech Republic 4 years after recognition of its risks still remains very high. This suggests that implementation of clinical trial results to clinical practice is very slow and ineffective.     

Conducted vasoconstriction is reduced in a mouse model of sepsis

The ability of an arteriole to conduct vasomotor responses along its length contributes to the control of organ perfusion. Sepsis, a systemic inflammatory response to infection, may compromise this control. We aimed to determine whether sepsis, induced by cecal ligation and perforation (CLP), reduces conducted vasoconstriction 24 h post-CLP. We locally stimulated mouse cremaster arterioles with KCl, measured the resulting local and the conducted constriction (500 microm upstream) and, based on these measurements, determined the communication ratio (CR(500)) as an index of the conducted response. Sepsis significantly reduced the CR(500) from 0.75 to 0.20. Based on a mathematical model, this reduction was predicted to have a significant impact on blood flow control. In septic mice, either a 1-hour washout of the cremaster muscle with physiological saline or a treatment of this muscle with the tyrosine kinase inhibitor PP-2 (100 nM) restored the CR(500) to the control level. Treatment of septic arterioles with the nitric oxide synthase inhibitor N(omega)-nitro-L-arginine methyl ester (100 microM) partially restored the CR(500) from 0.2 to 0.4. In control mice, lipopolysaccharide (LPS; 10 microg/ml) superfused over the cremaster muscle for 1 h reduced the CR(500); the nitric oxide (NO) donor S-nitroso-N-acetyl-penicillamine (50 microM) also reduced the CR(500). Thus, LPS and NO could be two factors mediating reduced conduction of vasoconstriction in sepsis. We conclude that sepsis reduces the KCl-induced conducted vasoconstriction in the mouse cremaster muscle by a tyrosine kinase- and nitric oxide- dependent mechanism.     

Cholinergic modulation of nucleus accumbens medium spiny neurons

The rat nucleus accumbens contains acetylcholine-releasing interneurons, presumed to play a regulatory role in the electrical activity of medium spiny output neurons. In order to examine this issue in detail, we made electrophysiological recordings in rat nucleus accumbens slices. These experiments showed that gamma-aminobutyric acid-mediated inhibition of the output neurons might be facilitated by activation of nicotinic acetylcholine receptors, in addition to being suppressed via activation of muscarinic acetylcholine receptors. In contrast, glutamatergic excitation of output neurons appeared to be inhibited by activation of muscarinic acetylcholine receptors and to be insensitive to activation of nicotinic acetylcholine receptors. The spontaneous firing frequency of cholinergic neurons appeared to be under control of both a muscarinic and a nicotinic pathway in a bi-directional manner. Finally, we made paired recordings in which the functional connection between cholinergic neurons and output neurons was monitored. Driving the cholinergic neurons at physiological firing frequencies stimulated gamma-aminobutyric acid-mediated inhibition of the output neurons, via activation of nicotinic acetylcholine receptors. The onset of this effect was slow and lacked a fixed delay. These data indicate that activation of nicotinic acetylcholine receptors in rat nucleus accumbens may mediate the facilitation of gamma-aminobutyric acid-mediated inhibition of medium spiny output neurons. Possible mechanisms of neurotransmission, mediating this cholinergic modulation are discussed.     

Cost-utility analysis of patient care in children with meningeal signs

OBJECTIVES: We designed a model of diagnostic and therapeutic interventions applied in children with meningeal signs. Using this model, we determined in a cost-utility analysis the consequences for society of different diagnostic strategies in terms of quality-adjusted life-years (QALYs) and costs. METHODS: Data were used from 360 children (0.1-15 years) visiting the pediatric emergency department of the Sophia Children's Hospital Rotterdam, The Netherlands (1988-98) with meningeal signs. Model inputs included probabilities of meningitis and adverse outcome, QALYs for years lived with long-term sequelae, and costs of tests and treatments. Mean outcome measures were costs and effects of diagnostic and therapeutic interventions in children suspected of bacterial meningitis, key determinants of the model outcomes, and evaluation of alternative diagnostic strategies and two vaccination programs in an analysis. RESULTS: The population comprised 99 children with bacterial meningitis (adverse outcome in 10), 36 with serious other bacterial infections, and 225 with self-limiting diseases. Key determinants were the risk of bacterial meningitis or sequelae, costs of treatment, and long-term morbidity. Minimizing lumbar punctures and empirical treatments using a diagnostic decision rule, without missing a single case of meningitis, was a dominant strategy to actual practice. Vaccination strategies of Streptococcus pneumoniae and Neisseria meningitidis resulted in our model in incremental cost-utility ratios of 401,965 Euro dollar ([symbol: see text])/QALY and [symbol: see text]22,635/QALY, respectively. CONCLUSIONS: Costs of long-term morbidity of bacterial meningitis largely outweigh diagnostic and treatment costs. Modeling interventions in children at risk of bacterial meningitis should include long-term consequences in terms of costs and QALYs.     

Tumor necrosis factor-alpha induces apoptosis associated with poly(ADP-ribose) polymerase cleavage in HT-29 colon cancer cells

BACKGROUND: Tumor necrosis factor-alpha (TNF-alpha) is known for its selective cytotoxic activity on tumour cells. We analysed the response of HT-29 human colon carcinoma cells to this cytokine. MATERIALS AND METHODS: After TNF-alpha treatment, cell proliferation, cell cycle, reactive oxygen species (ROS) production (flow cytometry), the amount of apoptotic cells (flow cytometry, fluorescence microscopy), cleavage of poly (ADP-ribose) polymerase (PARP) and caspase-3 activity (Western blotting) were detected. RESULTS: TNF-alpha induced a decrease of cell growth and viability, an accumulation of cells in the S-phase of the cell cycle, an increase of subdiploid cell population and nuclear chromatin condensation and fragmentation, but not sooner than 96-120 hours. However, earlier events characteristic of apoptosis occurred, such as caspase-3 activation, PARP cleavage to 89 kDa fragment and changes in ROS production. CONCLUSION: We demonstrated that, in addition to being an early marker of apoptosis, activation of caspase-3 and degradation of PARP may play a causative role in HT-29 cell death induced by TNF-alpha.