Standard procedures for adults in accredited sleep medicine centres in Europe.

The present paper describes standardized procedures within clinical sleep medicine. As such, it is a continuation of the previously published European guidelines for the accreditation of sleep medicine centres and European guidelines for the certification of professionals in sleep medicine, aimed at creating standards of practice in European sleep medicine. It is also part of a broader action plan of the European Sleep Research Society, including the process of accreditation of sleep medicine centres and certification of sleep medicine experts, as well as publishing the Catalogue of Knowledge and Skills for sleep medicine experts (physicians, non-medical health care providers, nurses and technologists), which will be a basis for the development of relevant educational curricula. In the current paper, the standard operational procedures sleep medicine centres regarding the diagnostic and therapeutic management of patients evaluated at sleep medicine centres, accredited according to the European Guidelines, are based primarily on prevailing evidence-based medicine principles. In addition, parts of the standard operational procedures are based on a formalized consensus procedure applied by a group of Sleep Medicine Experts from the European National Sleep Societies. The final recommendations for standard operational procedures are categorized either as 'standard practice', 'procedure that could be useful', 'procedure that is not useful' or 'procedure with insufficient information available'. Standard operational procedures described here include both subjective and objective testing, as well as recommendations for follow-up visits and for ensuring patients' safety in sleep medicine. The overall goal of the actual standard operational procedures is to further develop excellence in the practice and quality assurance of sleep medicine in Europe.

Angiotensin-(1-7), a protective peptide against vascular aging.

Vascular aging is a complex and multifaceted process that provokes profound molecular, structural, and functional changes in the vasculature. Eventually, these profound aging alterations make arteries more prone to vascular disease, including hypertension, atherosclerosis and other arterial complications that impact the organism beyond the cardiovascular system and accelerate frailty. For these reasons, preventing or delaying the hallmarks of vascular aging is nowadays a major health goal, especially in our aged societies. In this context, angiotensin(Ang)-(1-7), a major player of the protective branch of the renin-angiotensin system, has gained relevance over recent years as growing knowledge on its anti-aging properties is being unveiled. Here, we briefly review the main actions of Ang-(1-7) against vascular aging. These include protection against vascular cell senescence, anti-inflammatory and antioxidant effects together with the induction of cytoprotective systems. Ang-(1-7) further ameliorates endothelial dysfunction, a hallmark of vascular aging and disease, attenuates fibrosis and calcification and promotes protective angiogenesis and repair. Although further research is needed to better understand the anti-aging properties of Ang-(1-7) on the vasculature, this heptapeptide arises as a promising pharmacological tool for preventing vascular aging and frailty.

Induction of multiepitopic and long-lasting immune responses against tumour antigens by immunization with peptides, DNA and recombinant adenoviruses expressing minigenes.

The development of immunization strategies to induce strong and multiepitopic T-cell responses against tumour antigens is needed for anti-tumour immunotherapy. However, a common finding after immunization with complex antigens is the preferential induction of immune responses against immunodominant epitopes. In this study, with the aim of inducing multiepitopic responses against several common tumour antigens, we have designed a minigene construct encoding four human leucocyte antigen (HLA)-A2-restricted epitopes belonging to tumour antigens CEA (CEA-691 and CEA-571), MAGE2 (MAGE2-157) and MAGE3 (MAGE3-112), as well as the universal PADRE epitope recognized by T helper lymphocytes. To optimize the activation of immune responses against these epitopes, we have used different antigen formats (short peptides encompassing individual epitopes and DNA plasmids or adenoviral constructs expressing the minigene) in single or combined immunization schedules. A single immunization with either DNA plasmid or recombinant adenovirus induced a monospecific immune response against the immunodominant epitope CEA-571, whereas immunization with the peptide pool induced responses against all epitopes. Combination of peptide priming followed by a boost with the plasmid and the recombinant adenovirus expressing the minigene induced stronger, multi-specific and long-lasting immune responses, overcoming the immunodominance imposed by the main T-cell epitope. Moreover, these combined immunization strategies were able to induce responses that were able to recognize Mel624 HLA-A2+ tumour cells expressing MAGE2. These results suggest that heterologous immunization strategies combining peptides and DNA or recombinant adenoviruses can be useful to broaden the specificity and enhance the efficacy of subunit vaccines.

Monocyte-derived dendritic cells from HCV-infected patients transduced with an adenovirus expressing NS3 are functional when stimulated with the TLR3 ligand poly(I:C).

Dendritic cells (DC) transfected with an adenovirus encoding hepatitis C virus (HCV) NS3 protein (AdNS3) induce potent antiviral immune responses when used to immunize mice. However, in HCV infected patients, controversial results have been reported regarding the functional properties of monocyte-derived DC (MoDC), a cell population commonly used in DC vaccination protocols. Thus, with the aim of future vaccination studies we decided to characterize MoDC from HCV patients transfected with AdNS3 and stimulated with the TLR3 ligand poly(I:C). Phenotypic and functional properties of these cells were compared with those from MoDC obtained from uninfected individuals. PCR analysis showed that HCV RNA was negative in MoDC from patients after the culture period. Also, phenotypic analysis of these cells showed lower expression of CD80, CD86, and CD40, but similar expression of HLA-DR molecules as compared to MoDC from uninfected individuals. Functional assays of MoDC obtained from patients and controls showed a similar ability to activate allogeneic lymphocytes or to produce IL-12 and IL-10, although lower IFN-alpha levels were produced by cells from HCV patients after poly(I:C) stimulation. Moreover, both groups of MoDC induced similar profiles of IFN-gamma and IL-5 after stimulation of allogeneic T-cells. Finally, migration assays did not reveal any difference in their ability to respond to CCL21 chemokine. In conclusion, MoDC from HCV patients are functional after transduction with AdNS3 and stimulation with poly(I:C). These findings suggest that these cells may be useful for therapeutic vaccination in chronic HCV infection.

Gender differences in the effect of aspirin on retinal ischemia, prostanoid synthesis and nitric oxide production in experimental type 1-like diabetes.

BACKGROUND: The protective effect of acetylsalicylic acid (aspirin) against cardiovascular events is known to be weaker in women than in men. The present study was designed to test whether this effect of aspirin differed between sexes in an experimental model of diabetes with retinal ischemia. METHODS: We compared nondiabetic rats and rats after 1, 2 and 3 months of diabetes that were given 2 mg/kg/day p.o. of aspirin from the first day of diabetes. The variables recorded were platelet aggregation, production of thromboxane B(2) (TxB(2)), 6-keto-prostaglandin F(1alpha) and aortic nitric oxide, and the percentage of the retinal surface occupied by horseradish peroxidase (HRP)-permeable vessels. RESULTS: In female rats made diabetic, TxB(2) synthesis was more markedly reduced, and the percentage of HRP-permeable retinal vessels was less markedly reduced, than in their male counterparts. The response to aspirin treatment was weaker in female than in male diabetic rats in terms of inhibition of TxB(2) synthesis, increased nitric oxide production, and prevention of the increase in the percentage of retinal surface covered by HRP-permeable vessels. CONCLUSION: Aspirin was less effective in preventing retinal ischemia in experimental diabetes in female than in male rats.

Cut-off Points for Muscle Mass - Not Grip Strength or Gait Speed - Determine Variations in Sarcopenia Prevalence.

OBJECTIVES: The European Working Group on Sarcopenia in Older People (EWGSOP) has proposed different methods and cut-off points for the three parameters that define sarcopenia: muscle mass, muscle strength and physical performance. Although this facilitates clinical practice, it limits comparability between studies and leads to wide differences in published prevalence rates. The aim of this study was to assess how changes in cut-off points for muscle mass, gait speed and grip strength affected sarcopenia prevalence according to EWGSOP criteria. METHODS: Cross-sectional analysis of elderly individuals recruited from outpatient clinics (n=298) and nursing homes (n=276). We measured muscle mass, grip strength and gait speed and assessed how changes in cut-off points changed sarcopenia prevalence in both populations. RESULTS: An increase from 5.45 kg/m2 to 6.68 kg/m2 in the muscle mass index for female outpatients and nursing-home residents increased sarcopenia prevalence from 4% to 23% and from 9% to 47%, respectively; for men, for an increase from 7.25 kg/m2 to 8.87 kg/m2, the corresponding increases were from 1% to 22% and from 6% to 41%, respectively. Changes in gait speed and grip strength had a limited impact on sarcopenia prevalence. CONCLUSION: The cut-off points used for muscle mass affect the reported prevalence rates for sarcopenia and, in turn, affect comparability between studies. The main factors influencing the magnitude of the change are muscle mass index distribution in the population and the absolute value of the cut-off points: the same difference between two references (e.g., 7.5 kg/m2 to 7.75 kg/m2 or 7.75 kg/m2 to 8 kg/m2) may produce different changes in prevalence. Changes in cut-off points for gait speed and grip strength had a limited impact on sarcopenia prevalence and on study comparability.

Effects of aspirin plus alpha-tocopherol on brain slices damage after hypoxia-reoxygenation in rats with type 1-like diabetes mellitus.

Diabetes mellitus is a risk factor for cerebrovascular ischemic disease. Aspirin (acetylsalicylic acid) is the most widely used drug for the secondary prevention of thrombotic phenomena. It has been also recently demonstrated that alpha-tocopherol influenced in vitro the antiplatelet effect of aspirin. The aim of the present study is to evaluate the effects aspirin plus alpha-tocopherol on cerebral oxidative stress, prostaglandin production and the nitric oxide pathway in a model of hypoxia-reoxygenation in rat brain slices. Our results show an imbalance in brain oxidative status (reflected mainly as the increase in lipid peroxides) as a result of diabetes itself rather than a failure of the glutathione-based antioxidant system. Moreover, our results also show a higher concentration of prostaglandins in the brain of diabetic animals and a higher nitric oxide concentration, mainly through a high iNOS activity. After 180 min of post-hypoxia reoxygenation, LDH activity was 40.6% higher in animals with diabetes, in comparison to non-diabetic animals. The increase of the LDH efflux observed in non-treated rats was reduced by 31.2% with aspirin, by 34.7% with alpha-tocopherol and by 69.8% with the association aspirin-alpha-tocopherol. The accumulation of prostaglandin E2 observed in diabetic non-treated rats was reduced statistically after the treatment with aspirin (34.2% inhibition), alpha-tocopherol (19.3% inhibition) or the association aspirin-alpha-tocopherol (54.4% inhibition). Nitric oxide production after 180 min reoxygenation was significantly reduced in aspirin (36.4%), alpha-tocopherol (22.7%) and aspirin-alpha-tocopherol (77.8%) treated rats with respect to diabetic non-treated animals; this was related mainly with a reduction in iNOS activity. The association between aspirin and alpha tocopherol could protects against brain ischemic-reperfusion damage with a better profile than aspirin alone.

Antioxidant and antiplatelet effects of the alpha-tocopherol-aspirin combination in type 1-like diabetic rats.

We analyze the effect of the combination of acetylsalicylic acid (2 mg/kg/day p.o.) and alpha-tocopherol (25 mg/kg/day p.o.) in a type-1-like experimental model of diabetes mellitus on platelet factors, endothelial antithrombotic factors and tissue oxidative stress. In diabetic rats, the combination of drugs had a greater inhibitory effect on platelet aggregation than in untreated control animals with diabetes (88.87%). The combination of drugs had little effect on the inhibition of thromboxane production (-90.81%) in comparison to acetylsalicylic acid alone (-84.66%), potentiated prostacyclin production (+162%) in comparison to alpha-tocopherol alone (+30.55%), and potentiated nitric oxide production (+241%) in comparison to either drug alone (acetylsalicylic acid +125%, alpha-tocopherol +142%). The combination of the two drugs improved the thromboxane/prostacyclin balance (0.145+/-0.009) in comparison to untreated diabetic animals (4.221+/-0.264) and in untreated healthy animals (0.651+/-0.045). It did not potentiate the antioxidant effect of either drug alone, but did increase tissue concentrations of reduced glutathione, especially in vascular tissue (+90.09% in comparison to untreated animals). In conclusion, in the experimental model of diabetes tested here, the combination of acetylsalicylic acid and alpha-tocopherol led to beneficial changes that can help protect tissues from thrombotic and ischemic phenomena.

[Cardiovascular risk study in patients with renin-angiotensin system blockade by means of the proteone of circulating extracellular vesicles]. / Estudio del riesgo cardiovascular en pacientes con bloqueo del sistema renina-angiotensina a través del proteoma de las vesículas extracelulares circulantes.

INTRODUCTION: Extracellular vesicles (EVs) are released to the bloodstream by certain cell types due to transport, activation and cell death processes. Blood count of EVs from platelet and endothelial origin has been proved to be a cardiovascular risk biomarker. Thus, EVs proteome might reflect the underlying cellular processes in hypertensive patients with albuminuria. MATERIAL AND METHODS: Protein content of circulating EVs was analyzed by liquid chromatography coupled to mass spectrometry. EVs were isolated by an ultracentrifugation protocol optimized in order to avoid contamination by blood plasma proteins. Purity of the isolated fraction was verified by electronic and confocal microscopy, and by flow cytometry. RESULTS: We hereby show a method to isolate circulating EVs from hypertensive patients with/without albuminuria with high yield and purity. Besides, we provide a reference proteome of the EVs of these patients, composed of 2,463 proteins, and prove that the proteins carried by these vesicles are associated with crucial processes involved in the inherent cardiovascular risk. CONCLUSION: The proteome of circulating EVs is an interesting source of indicators in the evaluation of cardiovascular risk in hypertensive patients with renin-angiotensin system blockage.

[Healthy sleep: evidence and guidelines for action. Official document of the Spanish Sleep Society]. / Sueño saludable: evidencias y guias de actuacion. Documento oficial de la Sociedad Española de Sueño.

One of the main objectives of the Spanish Sleep Society is to promote healthy sleep in both the general population and in health professionals. This document aims to conduct a review of the current scientific literature on sleep habits that can serve as the basis on which to establish a set of general recommendations, regarding healthy sleep, for use by the general population in Spain as well as to identify the main challenges faced by research into sleep habits. The document has been developed by a multidisciplinary team made up of members of the Spanish Sleep Society who are experts in paediatric sleep medicine, clinical neurophysiology, pulmonology, neurology, chronobiology, physiology and psychology. The existing scientific literature dealing with sleep habits in the general population was reviewed, and the following aspects were addressed: the current state of sleep habits in the Spanish population; a generic review of the optimum number of hours of sleep; the impact of the environmental setting (noise, temperature, illumination, etc.), hours of sleep, diet and sport, together with several specific sections for children and teenagers, shift-workers and drivers of different vehicles. The conclusions from all the aspects addressed in this document have resulted in a set of final general recommendations that will serve as a guide for the general population and health professionals. Likewise, the principal environmental challenges and future lines of research are also discussed.

Performance of the Finnish Diabetes Risk Score and a Simplified Finnish Diabetes Risk Score in a Community-Based, Cross-Sectional Programme for Screening of Undiagnosed Type 2 Diabetes Mellitus and Dysglycaemia in Madrid, Spain: The SPREDIA-2 Study.

AIM: To evaluate the performance of the Finnish Diabetes Risk Score (FINDRISC) and a simplified FINDRISC score (MADRISC) in screening for undiagnosed type 2 diabetes mellitus (UT2DM) and dysglycaemia. METHODS: A population-based, cross-sectional, descriptive study was carried out with participants with UT2DM, ranged between 45-74 years and lived in two districts in the north of metropolitan Madrid (Spain). The FINDRISC and MADRISC scores were evaluated using the area under the receiver operating characteristic curve method (ROC-AUC). Four different gold standards were used for UT2DM and any dysglycaemia, as follows: fasting plasma glucose (FPG), oral glucose tolerance test (OGTT), HbA1c, and OGTT or HbA1c. Dysglycaemia and UT2DM were defined according to American Diabetes Association criteria. RESULTS: The study population comprised 1,426 participants (832 females and 594 males) with a mean age of 62 years (SD = 6.1). When HbA1c or OGTT criteria were used, the prevalence of UT2DM was 7.4% (10.4% in men and 5.2% in women; p<0.01) and the FINDRISC ROC-AUC for UT2DM was 0.72 (95% CI, 0.69-0.74). The optimal cut-off point was ≥13 (sensitivity = 63.8%, specificity = 65.1%). The ROC-AUC of MADRISC was 0.76 (95% CI, 0.72-0.81) with ≥13 as the optimal cut-off point (sensitivity = 84.8%, specificity = 54.6%). FINDRISC score ≥12 for detecting any dysglycaemia offered the best cut-off point when HbA1c alone or OGTT and HbA1c were the criteria used. CONCLUSIONS: FINDRISC proved to be a useful instrument in screening for dysglycaemia and UT2DM. In the screening of UT2DM, the simplified MADRISC performed as well as FINDRISC.

Lipid peroxidation and glutathione system in hyperlipemic rabbits: influence of olive oil administration.

We studied the effect of supplementation (10% w/w) of a hyperlipemic diet (1% cholesterol) with olive oil (OLIV) for 6 weeks in four groups of 10 rabbits each. At the end of this period, we determined lipid peroxidation, glutathione content, and glutathione peroxidase, reductase and transferase activities in liver, brain, heart, aorta and platelets. The atherogenic diet increased tissue lipid peroxidation and decreased the protective antioxidant effect of glutathione. Dietary supplementation with olive oil reduced tissue lipid peroxidation by 71.6% in liver, 20.3% in brain, 84.5% in heart, 63.6% in aorta, 72% in platelets. The ratios total/oxidized glutathione were increased in all tissues (49% in liver, 48% in brain, 45% in heart, 83% in aorta, 70% in platelets). Olive oil increased glutathione peroxidase and transferase activities in all tissues. We conclude that in rabbits made hyperlipemic with a diet rich in saturated fatty acids, olive oil decreased tissue oxidative stress.

Immunomodulation induced by synthetic peptides derived from Staphylococcus aureus protein A.

Peptides from 10 to 22 amino acids containing sequences encompassed by Staphylococcus aureus protein A were synthesized. Some of these peptides, when present in cultures of lymphomononuclear cells from healthy donors or from cancer patients (melanoma, breast carcinoma, non-Hodgkin lymphoma and renal cell carcinoma) promoted: (i) changes in the phenotype of the lymphomononuclear population, (ii) stimulation of monocytes (release of IL-1 and TNF-alpha), and (iii) an increase in cytotoxicity against K562, Daudi and HT-29 cells. Isolated monocytes responded also to those peptides with a release of IL-1 and TNF alpha and an increase of cytotoxicity against HT-29 cells. It was found that the active peptides had the following structural pattern: a length of at least 15 amino-acid residues with a proline at position 6, valine, leucine, isoleucine, glycine, alanine or lysine at position 2, and glutamic or aspartic acid at position 11. Replacement of Pro at position 6 with any other residue turned the peptide inactive. Replacement of residues at positions 2 and 11 with amino-acid residues other than those required for activity resulted in compounds with a marked decrease in the immunomodulating properties described, or lacking these properties altogether.

Protective effect of triflusal and its main metabolite HTB in an in vitro model of anoxia-reoxygenation in rat brain slices: comparison with acetylsalicylic and salicylic acids.

Triflusal is a fluorinated derivative of acetylsalicylic acid (ASA) with demonstrated antithrombotic activity. Recently, evidence for a neuroprotective effect has been obtained. The aim of this study was to compare the neuroprotective effects of the main metabolite of triflusal (2-hydroxy-4-trifluoromethylbenzoic acid, HTB) and the ASA metabolite salicylic acid (SA) in an in vitro model of anoxia-reoxygenation in rat brain slices. Rat brain slices (n=10 per group) were subjected to a period of anoxia followed by 180 min reoxygenation. We measured oxidative stress parameters (lipid peroxidation, glutathione system), prostaglandins (PGE(2)), nitric oxide pathway activity (NO) (nitrites+nitrates, constitutive and inducible NO synthase activity) and LDH efflux, a biochemical marker of cell death. Various concentrations (10, 100 and 1,000 microM) of triflusal, HTB, ASA or SA were tested. Triflusal at 10, 100 and 1,000 microM decreased LDH efflux in rat brain slices after anoxia/reoxygenation by 24%, 35% and 49% respectively. This effect was proportionately greater than that of ASA (0%, 13% and 32%). The results with HTB were similar to those with triflusal, whereas SA showed a greater protective effect than ASA (13%, 33% and 35%). The antioxidant effects of HTB and SA on the biochemical mechanisms of cell damage studied here were also greater than the effects of triflusal and ASA, a finding attributable mainly to the decrease in lipid peroxidation and to the ability of HTB to also increase glutathione levels. The triflusal metabolite reduced inducible NO synthase activity by 18%, 21% and 30%, whereas SA inhibited this activity by 9%, 17% and 23%. Triflusal and HTB led to greater increases in NO synthase than ASA or AS. In conclusion, the metabolite HTB plays an important role in the neuroprotective effect of triflusal, at least in the experimental model of anoxia-reoxygenation tested here.

Carcinoembryonic antigen as a target to induce anti-tumor immune responses.

Identification of relevant targets for cancer therapy is a major goal in cancer research. In this field, the identification of tumor antigens has opened the possibility of inducing specific anti-tumor immune responses. Among these antigens, carcinoembryonic antigen (CEA) is especially relevant because CEA is expressed in a wide variety of adenocarcinomas such as colon, rectum, pancreas, gastric, breast, etc. The present review focuses on different strategies to induce anti-CEA immune responses. In a first group of strategies, the antigen is administered using viral and bacterial vectors expressing CEA, dendritic cells loaded with CEA protein, or dendritic cells transfected with DNA or RNA expressing CEA. A second group of strategies is based on immunizations with antigenic peptide determinants from CEA, rather than with immunogens containing the whole protein. This has been possible due to the identification of different peptide determinants from CEA, which when presented by MHC class I molecules, are recognized by T cytotoxic lymphocytes. More recently, due to the importance of CD4(+) T cells in the induction of immune responses, T helper peptides presented by MHC class II molecules have also been identified. To overcome the poor immunogenicity of CEA-derived peptide determinants, a common feature of self-antigens, their sequence has been modified to improve binding to MHC molecules or recognition by T cell receptors. Finally, in order to enhance immunization efficacy, some of these strategies have combined the administration of immunogens and cytokines or co-stimulatory molecules. Some of the immunization protocols developed are being tested in clinical trials with promising results. Thus, CEA may prove to be a valuable target antigen for the therapy of a high number of malignancies.

Polymorphic variants of the beta2-adrenergic receptor (ADRB2) gene and ADRB2-related propanolol-induced dyslipidemia in the Colombian population.

Different polymorphisms of the ADRB2 gene encoding the beta-adrenergic receptor (ADRB2) are associated with changes in a variety of responses of the sympathetic nervous system (SNS). In this study, we have investigated the distribution of frequencies of ADRB2-related allelic variants (Arg16Gly, Gln27Glu, Thr164Ile) in the Colombian population, as well as the influence of the Gln27Glu polymorphism as a risk factor for the development of dyslipidemia following propranolol administration. Genotyping was performed in unrelated Colombian volunteers, using PCR-RFLP methods. To examine the association between the Gln27Glu polymorphism of the ADRB2 gene and dyslipidemia induced by propranolol, we recruited 19 healthy individuals who were homozygous for either the Gln27 (wild-type, N = 11) or the Glu27 (homozygous mutant, N = 8) genotype. Electrocardiography (ECG), heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), body mass index (BMI), serum lipid levels (T-CHO, HDL-CHO, TG), and fibrinogen were determined before and after propranolol administration. The distribution of genotypes was as follows: Arg16Arg 46%, Arg16Gly 47.4%, Gly16Gly 6.6%, Gln27Gln 44.7%, Gln27Glu 48.2%, and Glu27Glu 7.1%, with allelic frequencies of 69.7% for Arg16, 30.3% for Gly16, 68.8% for Gln27, and 31.2% for Glu27. The Thr164Ile polymorphism was found only in one subject, who was heterozygous for the isoleucine variant. Significant changes in physiological parameters (HR, SBP, DBP) have been found in association with ADRB2 variants in both native and mutant subgroups after propranolol intake. HDL-CHO levels diminished (p = 0.005) in native homozygous individuals (Gln27Gln), whereas TG levels were found increased (p = 0.012) in the mutant homozygous individuals (Glu27Glu). T-CHO levels and serum fibrinogen levels remained unaltered in both subgroups. The evidence that subjects homozygous for Gln27 in the ADRB2 gene show a significant reduction of HDL-CHO levels, as well as the increased TG levels in subjects homozygous for Glu27 after propranolol administration, suggest that the Gln27Glu polymorphism represents a risk factor for dyslipidemia induced by propranolol. These results may contribute to a better understanding of the mechanisms underlying dyslipidemia induced by ADRB2 antagonists.

Fast and asymptotic computation of the fixation probability for Moran processes on graphs.

Evolutionary dynamics has been classically studied for homogeneous populations, but now there is a growing interest in the non-homogeneous case. One of the most important models has been proposed in Lieberman et al. (2005), adapting to a weighted directed graph the process described in Moran (1958). The Markov chain associated with the graph can be modified by erasing all non-trivial loops in its state space, obtaining the so-called Embedded Markov chain (EMC). The fixation probability remains unchanged, but the expected time to absorption (fixation or extinction) is reduced. In this paper, we shall use this idea to compute asymptotically the average fixation probability for complete bipartite graphs K(n,m). To this end, we firstly review some recent results on evolutionary dynamics on graphs trying to clarify some points. We also revisit the 'Star Theorem' proved in Lieberman et al. (2005) for the star graphs K(1,m). Theoretically, EMC techniques allow fast computation of the fixation probability, but in practice this is not always true. Thus, in the last part of the paper, we compare this algorithm with the standard Monte Carlo method for some kind of complex networks.

Adenoviral gene transfer of interleukin 12 into tumors synergizes with adoptive T cell therapy both at the induction and effector level.

Tumors infected with a recombinant defective adenovirus expressing interleukin 12 (IL-12) undergo regression, associated with a cytotoxic T lymphocyte (CTL)-mediated antitumor immune response. In the present study we generated anti-CT26 CTLs by short-term coculture of CT26 cells and lymph node cells obtained from mice harboring subcutaneous CT26 tumors injected with an adenoviral vector expressing IL-12 (AdCMVIL-12), control adenovirus (AdCMVlacZ), or saline. Regression of small intrahepatic CT26 tumors in unrelated syngeneic animals was achieved with CTLs derived from mice whose subcutaneous tumors had been injected with AdCMVIL-12 but not with CTLs from the other two control groups. The necessary and sufficient effector cell population for adoptive transfer consisted of CD8+ T cells that showed anti-CT26 specificity partly directed against the AH1 epitope presented by H-2Ld. Interestingly, treatment of a subcutaneous tumor nodule with AdCMVIL-12, combined with intravenous adoptive T cell therapy with short-term CTL cultures, had a marked synergistic effect against large, concomitant live tumors. Expression of IL-12 in the liver in the vicinity of the hepatic tumor nodules, owing to spillover of the vector into the systemic circulation, appeared to be involved in the increased in vivo antitumor activity of injected CTLs. In addition, adoptive T cell therapy improved the outcome of tumor nodules transduced with suboptimal doses of AdCMVIL-12. Our data provide evidence of a strong synergy between gene transfer of IL-12 and adoptive T cell therapy. This synergy operates both at the induction and effector phases of the CTL response, thus providing a rationale for combined therapeutic strategies for human malignancies.