Second-line treatment strategies for RAS wild-type colorectal cancer: A systematic review and Network Meta-analysis (NMA).

BACKGROUND: The optimal strategy for second-line (IIL) treatment in KRAS wt metastatic colorectal cancer (mCRC) is not determined yet. METHODS: A random-effect NMA of phase II/III RCTs was conducted to evaluate IIL treatment for all-RAS wt mCRC, comparing anti-EGFR or anti-VEGF, and chemotherapy (CT). RESULTS: Overall, 11 RCTs (3613 patients) were included. In KRAS wt patients, PFS was improved with anti-VEGF (HR 0.43) and anti-EGFR (HR 0.63) vs CT. However, anti-VEGF based therapy had the highest likelihood of being ranked as the best treatment in terms of PFS (SUCRA 99.3%) and OS (SUCRA 99.4%). Bevacizumab-based treatment is most likely to be the best treatment in terms of PFS (SUCRA 89.1%) and OS (SUCRA 86.7%). CONCLUSIONS: Second line treatment with anti-VEGF and anti-EGFR improved PFS in mCRC patients, however, anti-VEGF based therapy, particularly CT plus bevacizumab, is the best treatment according to SUCRA in terms of PFS and OS.

caso clínico: enfermedad de darier y sifilis, la gran simuladora

Se presenta un caso clínico con el objetivo de dar a conocer una genodermatosis de baja frecuencia, enfermedad de Darier, que se presentó concomitantemente a una síflis tardía, que al ser tratada con penicilina, provocó una reacción adversa a la misma.

Influence of ceria nanoparticles on chemical structure and properties of segmented polyesters.

In this work, we present new nanocomposite materials derived from segmented copolyesters, comprising ethylene terephthalate (PET) segments and dimerized linoleic acid (DLA), and nanometric cerium oxide particles (CeO2). Nanoparticles were incorporated in situ during polycondensation in various concentrations, from 0.1 up to 0.6 wt.%. It was found that preparation of nanocomposites in situ, during polycondensation, had no significant influence on changes in segmental composition as determined from (1)H and (13)C, as well as 2D NMR. Thermal analysis and calculated degree of crystallinity showed that increasing concentration of ceria nanoparticles lead to an increase in mass content of PET crystallites in hard segments. The XRD investigations also showed an increased intensity of characteristic signals with increasing ceria concentration. Simultaneously, the incorporation of CeO2 led to an increase in tensile strength and elongation at break, indicating a reinforcing and plasticizing effect of ceria nanoparticles. However, the modulus at 10% strain decreased with increasing amount of nanoparticles. The in vitro culture of human cardiac progenitor cells (hCPCs) on the new materials indicated a homogenous cell displacement across the samples after 5 days with no signs of cytotoxicity, indicating good biocompatibility in vitro of CeO2-based nanocomposites and a potential for biomedical applications.

Interfacing Sca-1(pos) mesenchymal stem cells with biocompatible scaffolds with different chemical composition and geometry.

An immortalized murine mesenchymal stem cell line (mTERT-MSC) enriched for Lin(neg)/Sca-1(pos) fraction has been obtained through the transfection of MSC with murine TERT and single-cell isolation. Such cell line maintained the typical MSC self-renewal capacity and continuously expressed MSC phenotype. Moreover, mTERT-MSC retained the functional features of freshly isolated MSC in culture without evidence of senescence or spontaneous differentiation events. Thus, mTERT-MSC have been cultured onto PLA films, 30 and 100 microm PLA microbeads, and onto unpressed and pressed HYAFF-11 scaffolds. While the cells adhered preserving their morphology on PLA films, clusters of mTERT-MSC were detected on PLA beads and unpressed fibrous scaffolds. Finally, mTERT-MSC were not able to colonize the inner layers of pressed HYAFF-11. Nevertheless, such cell line displayed the ability to preserve Sca-1 expression and to retain multilineage potential when appropriately stimulated on all the scaffolds tested.

The role of predation in variation in body shape in guppies Poecilia reticulata: a comparison of field and common garden phenotypes.

The body shapes of both wild-caught and laboratory-reared male and female Trinidadian guppies Poecilia reticulata from two low-predation and two high-predation populations were studied, but predation regime did not seem to be the most important factor affecting body shape. Instead, complicated patterns of plasticity in body shape among populations and the sexes were found. In particular, populations differed in the depth of the caudal peduncle, which is the muscular region just anterior to the tail fin rays and from which most swimming power is generated. Strikingly, the direction of population differences in caudal peduncle depth observed in wild-caught individuals was reversed when P. reticulata were raised in a common laboratory environment.

Brain Natriuretic Peptide (BNP) regulates the production of inflammatory mediators in human THP-1 macrophages.

Brain Natriuretic Peptide (BNP), besides retaining vasodilatory, diuretic and natriuretic properties, is a vasoactive hormone that it is also involved in several cardiac diseases as well as severe sepsis and septic shock. All these conditions are characterized by an ongoing inflammatory response consisting in a complex interaction of pleiotropic mediators derived from plasma or cells, including monocytes and macrophages. However, the relationship between this hormone and inflammation remains to be elucidated. Therefore, the aim of the present study was to evaluate a possible BNP immunomodulatory activity on macrophages. Our results demonstrate that BNP regulates the production of major inflammatory molecules, such as reactive oxygen- and nitrogen species (ROS and RNS), leukotriene B(4) (LTB(4)), prostaglandin E(2) (PGE(2)); modulates the cytokines (TNF-alpha, IL-12 and IL-10) profile, and affects cell motility. These results furnish novel and brand-new proofs on BNP ability of modulating the production of inflammatory mediators in macrophages whose role has broad implications in inflammatory states where increased BNP levels have been reported.

Activatory properties of lysophosphatidic acid on human THP-1 cells.

Excessive leukocyte proliferation and proinflammatory mediators release represent common phenomena in several chronic inflammatory diseases. Multiple evidences identify lysophosphatidic acid (LPA), a small lipid endowed with pleiotropic activities, as an important modulator of both proliferation and activation of different cell types involved in several inflammation-associated pathologies. However, its possible role on monocyte proinflammatory activation is not fully understood yet. Aim of the present study was to investigate LPA effects on THP-1 cells in terms of proliferation, reactive oxygen intermediates (ROI) production and release of arachidonic acid-derived inflammatory mediators. Actually, LPA significantly increased both DNA synthesis and ROI production as well as prostaglandin E(2) release and the upregulation of LPA(3) receptor expression. These findings identified LPA as both a growth factor and a triggering mediator of proinflammatory response in THP-1 cells.

Role of atrial natriuretic peptide in the suppression of lysophosphatydic acid-induced rat aortic smooth muscle (RASM) cell growth.

Lysophosphatidic acid (LPA) is a lipid mediator with multiple biological functions. In the present study we investigated the possible role of atrial natriuretic peptide (ANP), a hormone affecting cardiovascular homeostasis and inducing antimitogenic effects in different cell types, on LPA-induced cell growth and reactive oxygen species (ROS) production in rat aortic smooth muscle (RASM) cells. Both LPA effects on cell growth and levels of ROS were totally abrogated by physiological concentrations of ANP, without modifying the overexpression of LPA-receptors. These effects were also affected by cell pretreatment with wortmannin, an inhibitor of phosphatidylinositol 3-kinase (PI3K). Moreover, the LPA-induced activation of Akt, a downstream target of PI3K, was completely inhibited by physiological concentrations of ANP, which were also able to inhibit p42/p44 phosphorylation. Taken together, our data suggest that PI3K may represent an important step in the LPA signal transduction pathway responsible for ROS generation and DNA synthesis in RASM cells. At same time, the enzyme could also represent an essential target for the antiproliferative effects of ANP.

Activatory properties of lysophosphatidic acid on human THP-1 cells.

Excessive leukocyte proliferation and proinflammatory mediators release represent common phenomena in several chronic inflammatory diseases. Multiple evidences identify lysophosphatidic acid (LPA), a small lipid endowed with pleiotropic activities, as an important modulator of both proliferation and activation of different cell types involved in several inflammation-associated pathologies. However, its possible role on monocyte proinflammatory activation is not fully understood yet. Aim of the present study was to investigate LPA effects on THP-1 cells in terms of proliferation, reactive oxygen intermediates (ROI) production and release of arachidonic acid-derived inflammatory mediators. Actually, LPA significantly increased both DNA synthesis and ROI production as well as prostaglandin E(2) release and the upregulation of LPA(3) receptor expression. These findings identified LPA as both a growth factor and a triggering mediator of proinflammatory response in THP-1 cells.

Dietary alpha-linolenic acid reduces COX-2 expression and induces apoptosis of hepatoma cells.

Fatty acid synthetase (FAS) is overexpressed in various tumor tissues, and its inhibition and/or malonyl-CoA accumulation have been correlated to apoptosis of tumor cells. It is widely recognized that both omega-3 and omega-6 polyunsaturated fatty acids (PUFAs) depress FAS expression in liver, although epidemiological and experimental reports attribute antitumor properties only to omega-3 PUFA. Therefore, we investigated whether lipogenic gene expression in tumor cells is differently regulated by omega-6 and omega-3 PUFAs. Morris hepatoma 3924A cells were implanted subcutaneously in the hind legs of ACI/T rats preconditioned with high-lipid diets enriched with linoleic acid or alpha-linolenic acid. Both-high lipid diets depressed the expression of FAS and acetyl-CoA carboxylase in tumor tissue, this effect correlating with a decrease in the mRNA level of their common sterol regulatory element binding protein-1 transcription factor. Hepatoma cells grown in rats on either diet did not accumulate malonyl-CoA. Apoptosis of hepatoma cells was induced by the alpha-linolenic acid-enriched diet but not by the linoleic acid-enriched diet. Therefore, in this experimental model, apoptosis is apparently independent of the inhibition of fatty acid synthesis and of malonyl-CoA cytotoxicity. Conversely, it was observed that apoptosis induced by the alpha-linolenic acid-enriched diet correlated with a decrease in arachidonate content in hepatoma cells and decreased cyclooxygenase-2 expression.

Oxidant-induced pHi/Ca2+ changes in rat aortic smooth muscle cells. The role of atrial natriuretic peptide.

The aim of this study was to investigate the effects of oxidative stress on PLD activity, [Ca2+]i and pHi levels and the possible relationship among them. Moreover, since atrial natriuretic peptide (ANP) protects against oxidant-induced injury, we investigated the potential protective role of the hormone in rat aortic smooth muscle (RASM) cells exposed to oxidative stress. Water-soluble 2,2'-Azobis (2-amidinopropane) dihydrochloride (AAPH) was used as free radical generating system, since it generates peroxyl radicals with defined reaction and the half time of peroxyl radicals is longer than other ROS. A significant increase of PLD activity was related to a significant decrease in pHi, while [Ca2+]i levels showed an increase followed by a decrease after cell exposure to AAPH. [Ca2+]i changes and pHi fall induced by AAPH were prevented by cadmium which inhibits a plasma membrane Ca2+ ATPase coupled to Ca2+/H+ exchanger, that operates the efflux of Ca2+ coupled to H+ influx. The involvement of PLD in pHi and [Ca2+]i changes was confirmed by calphostin-c treatment, a potent inhibitor of PLD, which abolished all AAPH-induced effects. Pretreatment of RASM cells with pharmacological concentrations of ANP attenuated the AAPH effects on PLD activity as well as [Ca2+]i and pHi changes, while no effects were observed with physiological ANP concentrations, suggesting a possible role of the hormone as defensive effector against early events of the oxidative stress.

Inhibitors of DNA methylation and histone deacetylation activate cytomegalovirus promoter-controlled reporter gene expression in human glioblastoma cell line U87.

The expression of many cellular genes is modulated by DNA methylation and histone acetylation. These processes can influence malignant cell transformation and are also responsible for the silencing of DNA constructs introduced into mammalian cells for therapeutic or research purposes. As a better understanding of these biological processes may contribute to the development of novel cancer treatments and to study the complex mechanisms regulating gene silencing, we established a cellular system suitable to dissect the mechanisms regulating DNA methylation and histone acetylation. For this purpose, we stably transfected the neuroblastoma cell line U87 with a cytomegalovirus promoter-driven reporter gene construct whose expression was analyzed following treatment with the DNA methylation inhibitor 5'-aza-2'-deoxycytidine or histone deacetylation inhibitor trichostatin A. Both substances reactivated the silenced cytomegalovirus promoter, but with different reaction kinetics. Furthermore, whereas the kinetics of reactivation by trichostatin A did not substantially change over the time range considered (5 days), reactivation induced by 5'-aza-2'-deoxycytidine showed profound differences between day 1 and longer time points. We showed that this effect is related to the down-regulation of DNA replication by 5'-aza-2'-deoxycytidine. Finally, we have shown that the simultaneous administration of trichostatin A and 5'-aza-2'-deoxycytidine results in reactivation of the CMV promoter according to a cooperative, not synergistic or additive, mechanism. In conclusion, our cellular system should represent a powerful tool to investigate the complex mechanisms regulating gene silencing and to identify new anticancer drugs.

Enhanced expression of hepatic lipogenic enzymes in an animal model of sedentariness.

The hindlimb-suspended rat was used as animal model to investigate the effects induced by immobilization of the skeletal muscle in the expression of the genes encoding hepatic lipogenic enzymes. Following a 14-day period of immobilization, rats were injected intraperitoneally with radioactive acetate, and the labeling of hepatic lipids and cholesterol was evaluated 15 min after the isotope injection. The incorporation of labeled acetate in lipids and cholesterol was almost three times higher in the liver of immobilized rats than in control animals as a consequence of the enhanced transcription of the genes encoding acetyl-CoA synthase, acetyl-CoA carboxylase, fatty acid synthase, and 3-hydroxy-3-methylglutaryl-CoA reductase. The high expression of the key enzymes for fatty acid and cholesterol synthesis induced by immobilization was not paralleled by an increase of the hepatic sterol-regulatory element binding protein (SREBP)-1 and SREBP-2 mRNA content. However, the expression of the mature form of SREBP-1 and SREBP-2 was higher in the nuclear fraction of immobilized rat liver than in controls due to a significant increase of the cleavage of the native proteins. Immobilization also affected the expression of proteins involved in lipid degradation. In fact, the hepatic content of peroxisome proliferator-activated receptor-alpha (PPARalpha) mRNA and of PPARalpha target genes encoding carnitine palmitoyl transferase-1 and acyl-CoA oxidase were significantly increased upon immobilization.

Selective changes in DNA binding activity of transcription factors in UM-X7.1 cardiomyopathic hamsters.

UM-X7.1 hamsters (CH) are considered a representative model for human cardiomyopathy. CH display the loss of the cytoskeletal delta-sarcoglycan protein, associated with myocardium remodeling and fatal reduction of heart functional efficiency. Even though altered redox balance and calcium homeostasis have already been reported to affect cardiomyocyte function, the molecular mechanisms underlying this pathology are largely unknown. We found no significant differences in DNA binding activity of redox-related (NF-kappaB, Sp1, AP-1 and AP-2) transcription factors in heart ventricles of 90 day-old CH, compared to normal animals. On the other hand, DNA binding activity of calcium-dependent transcription factors NF-AT3 and CREB were increased and decreased respectively in CH vs. normal ventricles. Western blot experiments confirmed the down regulation of CREB levels and suggest a novel regulation mechanism for this transcription factor in the heart. Our results are consistent with recent studies on NF-AT3, GATA4 and CREB transgenic mice, and provide clues for the comprehension of pathogenetic mechanisms of hamster hereditary cardiomyopathy.

Atrial natriuretic factor inhibits mitogen-induced growth in aortic smooth muscle cells.

Atrial natriuretic factor (ANF) is a polypeptide able to affect cardiovascular homeostasis exhibiting diuretic, natriuretic, and vasorelaxant activities. ANF shows antimitogenic effects in different cell types acting through R(2) receptor. Excessive proliferation of smooth muscle cells is a common phenomenon in diseases such as atherosclerosis, but the role of growth factors in the mechanism which modulate this process has yet to be clarified. The potential antimitogenic role of ANF on the cell growth induced by growth factors appears very intriguing. Aim of the present study was to investigate the possible involvement of ANF on rat aortic smooth muscle (RASM) cells proliferation induced by known mitogens and the mechanism involved. Our data show that ANF, at physiological concentration range, inhibits RASM cell proliferation induced by known mitogens such as PDGF and insulin, and the effect seems to be elicited through the modulation of phosphatidic acid (PA) production and MAP kinases involvement.

Weightlessness as an accelerated model of nutritional disturbances.

Food intake and eating patterns, body functions and composition are significantly altered by short-duration space flight. Prolonged missions lasting weeks or months further aggravate these changes, and are responsible for acute or chronic physical impairments at return to ground conditions. Current projects of missions to Mars, resulting in 2 years of microgravity conditions, stress the critical need for the development of optimal nutritional programs and physical countermeasures to prevent body mass and function alterations. This review outlines ground models of microgravity simulation, summarizes the major effects of weightlessness on body composition, protein metabolism, hormonal pattern, and muscle function, and addresses contradictory findings related to the oxidative stress secondary to space flight. Potential countermeasures, such as nutrient intake and physical conditioning, as well as areas of interest for future research both in ground and space medicine, are discussed.

Reliability of DSM-IV anxiety and mood disorders: implications for the classification of emotional disorders.

The reliability of current and lifetime Diagnostic and Statistical Manual of Mental Disorders (4th ed.; DSM-IV; American Psychiatric Association, 1994) anxiety and mood disorders was examined in 362 outpatients who underwent 2 independent administrations of the Anxiety Disorders Interview Schedule for DSM-IV: Lifetime version (ADIS-IV-L). Good to excellent reliability was obtained for the majority of DSM-IV categories. For many disorders, a common source of unreliability was disagreements on whether constituent symptoms were sufficient in number, severity, or duration to meet. DSM-IV diagnostic criteria. These analyses also highlighted potential boundary problems for some disorders (e.g., generalized anxiety disorder and major depressive disorder). Analyses of ADIS-IV-L clinical ratings (0-8 scales) indicated favorable interrater agreement for the dimensional features of DSM-IV anxiety and mood disorders. The findings are discussed in regard to their implications for the classification of emotional disorders.

Depressed responsiveness of phospholipase C isoenzymes to phosphatidic acid in congestive heart failure.

The cardiac sarcolemmal membrane cis -unsaturated fatty acid-sensitive phospholipase D hydrolyzes phosphatidylcholine to form phosphatidic acid. The functional significance of phosphatidic acid is indicated by its ability to increase [Ca(2+)](i)and augment cardiac contractile performance via the activation of phospholipase C. Accordingly, we tested the hypothesis that a defect occurs in the membrane level of phosphatidic acid and/or the responsiveness of cardiomyocytes to phosphatidic acid in congestive heart failure due to myocardial infarction. Myocardial infarction was produced in rats by ligation of the left coronary artery while sham-operated animals served as control. At 8 weeks after surgery, the experimental animals were at a stage of moderate congestive heart failure. Compared to sham controls, phosphatidic acid-mediated increase in [Ca(2+)](i), as determined by the fura 2-AM technique, was significantly reduced in failing cardiomyocytes. Immunoprecipitation of sarcolemmal phospholipase C isoenzymes using specific monoclonal antibodies revealed that the stimulation of phospholipase C gamma(1)and delta(1)phosphatidylinositol 4,5-bisphosphate hydrolyzing activities by phosphatidic acid was decreased in the failing heart. Although the activity of phospholipase C beta(1)in the failing heart was higher than the control, phosphatidic acid did not stimulate this isoform in control sarcolemma, and produced an inhibitory action in the failing heart preparation. Furthermore, the specific binding of phosphatidic acid to phospholipase C gamma(1)and delta(1)isoenzymes was decreased, whereas binding to phospholipase beta(1)was absent in the failing heart. A reduction in the intramembranal level of phosphatidic acid derived via cis -unsaturated fatty acid-sensitive phospholipase D was also seen in the failing heart. These findings suggest that a defect in phosphatidic acid-mediated signal pathway in sarcolemma may represent a novel mechanism of heart dysfunction in congestive heart failure.

Insulin deficiency and reduced expression of lipogenic enzymes in cardiomyopathic hamster.

Evidence is given that the heart of the cardiomyopathic UM-X7.1 hamster has a lipid composition different from that of the same tissue isolated from animals of the Syrian hamster parent strain. Also, noncardiac tissues from cardiomyopathic and healthy hamsters exhibit significant compositional differences. On the basis of these preliminary observations, a comparative study of the hepatic biosynthesis of lipids in cardiomyopathic and healthy Syrian hamsters was undertaken. The results obtained indicate that the cardiomyopathic hamster is characterized by a generalized disturbance of lipid metabolism. In particular, the fatty acid synthase and stearoyl-CoA desaturase activities were significantly lower in the liver of UM-X7.1 hamsters than in age-matched healthy controls fed the same diet. Northern blot analysis of the mRNAs encoding the two enzymatic proteins and the "lipogenic" S14 nuclear protein indicated that the transcription of the respective genes was impaired in UM-X7.1.Short-term dietary manipulations modulated the expression of the above-mentioned genes both in cardiomyopathic and healthy animals. However, dietary carbohydrates were less effective in inducing the expression of lipogenic enzymes in UM-X7.1 liver than healthy controls. The main determinant of the metabolic defect pointed out in the present work appears to be represented by the low insulin level detectable in the plasma of the cardiomyopathic hamster.-Vecchini, A., L. Binaglia, M. Bibeau, M. Minieri, F. Carotenuto, and P. Di Nardo. Insulin deficiency and reduced expression of lipogenic enzymes in cardiomyopathic hamster. J. Lipid Res. 2001. 42: 96;-105.