Inter-fractional monitoring of [Formula: see text]C ions treatments: results from a clinical trial at the CNAO facility.

The high dose conformity and healthy tissue sparing achievable in Particle Therapy when using C ions calls for safety factors in treatment planning, to prevent the tumor under-dosage related to the possible occurrence of inter-fractional morphological changes during a treatment. This limitation could be overcome by a range monitor, still missing in clinical routine, capable of providing on-line feedback. The Dose Profiler (DP) is a detector developed within the INnovative Solution for In-beam Dosimetry in hadronthErapy (INSIDE) collaboration for the monitoring of carbon ion treatments at the CNAO facility (Centro Nazionale di Adroterapia Oncologica) exploiting the detection of charged secondary fragments that escape from the patient. The DP capability to detect inter-fractional changes is demonstrated by comparing the obtained fragment emission maps in different fractions of the treatments enrolled in the first ever clinical trial of such a monitoring system, performed at CNAO. The case of a CNAO patient that underwent a significant morphological change is presented in detail, focusing on the implications that can be drawn for the achievable inter-fractional monitoring DP sensitivity in real clinical conditions. The results have been cross-checked against a simulation study.

Effects of vineyard soil management on the characteristics of soils and roots in the lower Oltrepò Apennines (Lombardy, Italy).

Cultivation of grapevines in sloping soils is very widespread all over the world, representing also fundamental branch of local economy of several hilly areas. Vineyards can be managed in different ways. Agronomical practices in inter-rows can be significantly different and may influence deeply the soil properties and the grapevine root development. Therefore, this paper aimed to analyze the effects of different management practices of inter-rows. We focused on the traditional agricultural techniques of tillage and permanent grass mulching as well as the alternation of these two practices between adjacent inter-rows, in terms of: i) soil physical properties; ii) soil hydrological properties; iii) root density; iv) root mechanical properties and root reinforcement; as well as v) biodiversity. The research was conducted in several test-sites of Oltrepò Pavese (Lombardy region, north-western Italy), one of the most important Italian zones for wine production in northern Italian Apennines. Among the examined soil properties, hydraulic conductivity was the most influenced soil property by different soil management practices. The absence of soil tillage allowed to increase superficial (first 0.2 m of soil) hydraulic conductivity, as a consequence of higher macroporosity and amount in organic matter. Vineyards with alternation management (grass mulching together with tillage) of inter-rows had the highest root density and the strongest root reinforcement, of up to 45% in comparison to permanent grass cover, and up to 67-73% in comparison to tilled vineyards. Soil microarthropod communities had more complexity where sustainable agricultural practices (permanent grass cover; alternation management of the inter-rows) were applied. The results of this study yielded important information to establish effective management practices of vineyards such as conserving organic matter and reducing slope instabilities by a better development of root apparatus in the soil.

Footprints of BK and JC polyomaviruses in specimens from females affected by spontaneous abortion.

STUDY QUESTION: Are JC polyomavirus (JCPyV) and BK polyomavirus (BKPyV) infections associated with spontaneous abortion (SA)? SUMMARY ANSWER: There is no association of JCPyV or BKPyV with SA. WHAT IS KNOWN ALREADY: A large number of risk factors have been associated with SA. The role of polyomaviruses, including JCPyV and BKPyV, in SA remains to be clarified. STUDY DESIGN, SIZE, DURATION: This is a case-control study including women affected by spontaneous abortion (SA, n = 100, the cases) and women who underwent voluntary interruption of pregnancy (VI, n = 100, the controls). PARTICIPANTS/MATERIALS, SETTING, METHODS: Viral DNAs were investigated by qualitative PCR and quantitative droplet-digital PCR (ddPCR) in matched chorionic villi tissues and peripheral blood mononuclear cells (PBMCs) from SA (n = 100) and VI (n = 100). Indirect ELISAs with mimotopes/synthetic peptides corresponding to JCPyV and BKPyV viral capsid protein 1 epitopes were then employed to investigate specific IgG antibodies against JCPyV and BKPyV in human sera from SA (n = 80) and VI (n = 80) cohorts. MAIN RESULTS AND THE ROLE OF CHANCE: JCPyV DNA was detected in 51% and 61% of SA and VI samples, respectively, with a mean viral DNA load of 7.92 copy/104 cells in SA and 5.91 copy/104 cells in VI (P > 0.05); BKPyV DNA was detected in 11% and 12% of SA and VI specimens, respectively, with a mean viral DNA load of 2.7 copy/104 cells in SA and 3.08 copy/104 cells in VI (P > 0.05). JCPyV was more prevalent than BKPyV in both SA and VI specimens (P < 0.0001). In PBMCs from the SA and VI cohorts, JCPyV DNA was detected with a prevalence of 8% and 12%, respectively, with a mean viral DNA load of 2.29 copy/104 cells in SA and 1.88 copy/104 cells in VI (P > 0.05). The overall prevalence of serum IgG antibodies against JCPyV detected by indirect ELISAs was 52.5% and 48.7% in SA and VI groups, respectively, whereas BKPyV-positive sera were found in 80% SA and 78.7% VI samples. LIMITATIONS, REASONS FOR CAUTION: This study did not investigate the presence of viral mRNA and/or proteins, which are indicative of an active viral infection, and these might be taken into consideration in future studies. WIDER IMPLICATIONS OF THE FINDINGS: JCPyV and BKPyV DNA sequences were detected and quantitatively analyzed for the first time by PCR/ddPCR in chorionic villi tissues and PBMCs from SA and VI specimens. Moreover specific immunological approaches detected serum IgG against JCPyV/BKPyV. Statistical analyses, however, do not indicate an association between these polyomaviruses and SA. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by the University of Ferrara, FAR research grants and the University Hospital of Ferrara/University of Ferrara joint grant. No potential conflicts of interest were disclosed.

Use of the synergist piperonyl butoxide can slow the development of alpha-cypermethrin resistance in the whitefly Bemisia tabaci.

The development of insecticide resistance in insect pests of crops is a growing threat to sustainable food production, and strategies that slow the development of resistance are therefore urgently required. The insecticide synergist piperonyl butoxide (PBO) inhibits certain insect detoxification systems and so may delay the evolution of metabolic resistance. In the current study we characterized resistance development in the silverleaf whitefly, Bemisia tabaci, after selection with either a neonicotinoid (thiacloprid) or pyrethroid (alpha-cypermethrin) insecticide alone or in combination with PBO. Resistance development was significantly suppressed (> 60%) in the line selected with alpha-cypermethrin + PBO compared to the line selected with alpha-cypermethrin alone. RNA sequencing (RNAseq) analyses revealed an increase in frequency of a knock-down resistance mutation but no differentially expressed genes were identified that could explain the sensitivity shift. No significant difference was observed in the level of resistance between the thiacloprid and thiacloprid + PBO selected lines, and RNA sequencing (RNAseq) analyses revealed that the cytochrome P450 monooxygenase CYP6CM1, known to metabolize neonicotinoids, was significantly upregulated (>10-fold) in both lines. The findings of this study demonstrate that PBO used in combination with certain insecticides can suppress the development of resistance in a laboratory setting; however, the mechanism by which PBO supresses resistance development remains unclear.

Qualitative Sybr Green real-time detection of single nucleotide polymorphisms responsible for target-site resistance in insect pests: the example of Myzus persicae and Musca domestica.

Chemical insecticides have been widely used to control insect pests, leading to the selection of resistant populations. To date, several single nucleotide polymorphisms (SNPs) have already been associated with insecticide resistance, causing reduced sensitivity to many classes of products. Monitoring and detection of target-site resistance is currently one of the most important factors for insect pest management strategies. Several methods are available for this purpose: automated and high-throughput techniques (i.e. TaqMan or pyrosequencing) are very costly; cheaper alternatives (i.e. RFLP or PASA-PCRs) are time-consuming and limited by the necessity of a final visualization step. This work presents a new approach (QSGG, Qualitative Sybr Green Genotyping) which combines the specificity of PASA-PCR with the rapidity of real-time PCR analysis. The specific real-time detection of Cq values of wild-type or mutant alleles (amplified used allele-specific primers) allows the calculation of ΔCqW-M values and the consequent identification of the genotypes of unknown samples, on the basis of ranges previously defined with reference clones. The methodology is applied here to characterize mutations described in Myzus persicae and Musca domestica and we demonstrate it represents a valid, rapid and cost-effective technique that can be adopted for monitoring target-site resistance in field populations of these and other insect species.

Serum antibodies from epileptic patients react, at high prevalence, with simian virus 40 mimotopes.

BACKGROUND AND PURPOSE: It has been demonstrated that inflammation may contribute to epileptogenesis and cause neuronal injury in epilepsy. In this study, the prevalence of antibodies to simian virus 40 (SV40), a kidney and neurotropic polyomavirus, was investigated in serum samples from 88 epileptic children/adolescents/young adults. METHODS: Serum antibodies reacting to specific SV40 peptides were analysed by indirect enzyme-linked immunosorbent assay. Synthetic peptides corresponding to the epitopes of viral capsid proteins 1-3 were used as SV40 antigens. RESULTS: A significantly higher prevalence of antibodies against SV40 was detected in sera from epileptic patients compared to controls (41% vs. 19%). Specifically, the highest significant difference was revealed in the cohort of patients from 1.1 to 10 years old (54% vs. 21%), with a peak in the sub-cohort of 3.1-6 years old (65% vs. 18%). CONCLUSION: Our immunological data suggest a strong association between epilepsy and the SV40 infection.

Karyotype variations in Italian populations of the peach-potato aphid Myzus persicae (Hemiptera: Aphididae).

In this study, we present cytogenetic data regarding 66 Myzus persicae strains collected in different regions of Italy. Together with the most common 2n = 12 karyotype, the results showed different chromosomal rearrangements: 2n = 12 with A1-3 reciprocal translocation, 2n = 13 with A1-3 reciprocal translocation and A3 fission, 2n = 13 with A3 fission, 2n = 13 with A4 fission, 2n = 14 with X and A3 fissions. A 2n = 12-13 chromosomal mosaicism has also been observed. Chromosomal aberrations (and in particular all strains showing A1-3 reciprocal translocation) are especially frequent in strains collected on tobacco plants, and we suggest that a clastogenic effect of nicotine, further benefited by the holocentric nature of aphid chromosomes, could be at the basis of the observed phenomenon.

Human mesenchymal stem cells and biomaterials interaction: a promising synergy to improve spine fusion.

PURPOSE: Spine fusion is the gold standard treatment in degenerative and traumatic spine diseases. The bone regenerative medicine needs (i) in vitro functionally active osteoblasts, and/or (ii) the in vivo induction of the tissue. The bone tissue engineering seems to be a very promising approach for the effectiveness of orthopedic surgical procedures, clinical applications are often hampered by the limited availability of bone allograft or substitutes. New biomaterials have been recently developed for the orthopedic applications. The main characteristics of these scaffolds are the ability to induce the bone tissue formation by generating an appropriate environment for (i) the cell growth and (ii) recruiting precursor bone cells for the proliferation and differentiation. A new prototype of biomaterials known as "bioceramics" may own these features. Bioceramics are bone substitutes mainly composed of calcium and phosphate complex salt derivatives. METHODS: In this study, the characteristics bioceramics bone substitutes have been tested with human mesenchymal stem cells obtained from the bone marrow of adult orthopedic patients. RESULTS: These cellular models can be employed to characterize in vitro the behavior of different biomaterials, which are used as bone void fillers or three-dimensional scaffolds. CONCLUSIONS: Human mesenchymal stem cells in combination with biomaterials seem to be good alternative to the autologous or allogenic bone fusion in spine surgery. The cellular model used in our study is a useful tool for investigating cytocompatibility and biological features of HA-derived scaffolds.

Efficacy and safety of low-dose metronomic chemotherapy with capecitabine in heavily pretreated patients with metastatic breast cancer.

AIM: Registered dose capecitabine monotherapy is active against metastatic breast cancer (MBC), but retrospective analyses indicate that lower doses may be as effective and better tolerated. This study was conducted to assess the safety and efficacy of metronomic capecitabine in heavily pretreated patients with MBC. PATIENTS AND METHODS: In this phase II study 60 MBC patients received continuous metronomic capecitabine monotherapy (1500 mg once a day). Primary endpoint was clinical benefit rate, secondary end points were clinical benefit rates (CBRs), tumour response rates (RRs), overall survival (OS), time to progression (TTP), duration of response (DOR) and toxicity. RESULTS: Fifty eight assessable patients received two or more 28-day cycles of metronomic capecitabine. The CBR was 62%. Median DOR was 7 months. Median TTP and OS were 7 and 17 months, respectively. Two partial responses and 7 cases of stable disease were recorded in 13 patients who had previously received capecitabine intermittently (2000 mg/m(2)/day on days 1-14 every 21 days) as first- or subsequent-line treatment for MBC. Grade 3-4 adverse events were uncommon; haematologic toxicity was infrequent (5%) and consistently mild. CONCLUSION: This regimen of metronomic capecitabine displayed good activity and excellent tolerability in MBC patients, including those who had previously received the drug at standard doses.

Molecularly targeted endocrine therapies for breast cancer.

The identification of the estrogen receptor (ER) provided the first target for antiestrogenic therapeutic agents. Endocrine therapies, either by blocking or downregulating the receptor or by suppressing the estrogen production, inhibit the proliferative effect of estradiol on ER. While the activity on ER is considered a real target-mediated therapy, the effect on enzymatic activity involved in estrogen production (mainly inhibition of aromatase by aromatase inhibitors, AIs, and ovarian ablation) could be considered an "indirect" targeted strategy. In addiction to the direct ligand-ER signal, the complexity of endocrine and non endocrine pathways has led to combination therapies against different targets. Tamoxifen is the widely investigated, most used and representative of drugs blocking the ER and has been introduced in the advanced disease, in neoadjuvant and adjuvant setting and for chemo-prevention of high risk women. Its role has been challenged in the last years by the introduction of third generation aromatase inhibitors that have proven a higher activity than tamoxifen and different toxicity. Several other SERMs (selective estrogen receptor modulators) have been investigated, but none of them was clearly superior to tamoxifen. SERDs (selective estrogen receptor downregulators) act as pure estrogen antagonist. They are used in the treatment of advanced breast cancers and their role in other settings still needs further investigation. Here we discuss the well established data with SERMs, SERDs and AIs, mechanisms underlying resistance and rationale for recycling endocrine compounds and for simultaneously targeting different pathways.

Neurotensin receptor mechanisms and its modulation of glutamate transmission in the brain: relevance for neurodegenerative diseases and their treatment.

The extracellular accumulation of glutamate and the excessive activation of glutamate receptors, in particular N-methyl-D-aspartate (NMDA) receptors, have been postulated to contribute to the neuronal cell death associated with chronic neurodegenerative disorders such as Parkinson's disease. Findings are reviewed indicating that the tridecaptide neurotensin (NT) via activation of NT receptor subtype 1 (NTS1) promotes and reinforces endogenous glutamate signalling in discrete brain regions. The increase of striatal, nigral and cortical glutamate outflow by NT and the enhancement of NMDA receptor function by a NTS1/NMDA interaction that involves the activation of protein kinase C may favour the depolarization of NTS1 containing neurons and the entry of calcium. These results strengthen the hypothesis that NT may be involved in the amplification of glutamate-induced neurotoxicity in mesencephalic dopamine and cortical neurons. The mechanisms involved may include also antagonistic NTS1/D2 interactions in the cortico-striatal glutamate terminals and in the nigral DA cell bodies and dendrites as well as in the nigro-striatal DA terminals. The possible increase in NT levels in the basal ganglia under pathological conditions leading to the NTS1 enhancement of glutamate signalling may contribute to the neurodegeneration of the nigro-striatal dopaminergic neurons found in Parkinson's disease, especially in view of the high density of NTS1 receptors in these neurons. The use of selective NTS1 antagonists together with conventional drug treatments could provide a novel therapeutic approach for treatment of Parkinson's disease.

Prenatal exposure to the cannabinoid receptor agonist WIN 55,212-2 and carbon monoxide reduces extracellular glutamate levels in primary rat cerebral cortex cell cultures.

The effects of prenatal exposure to the cannabinoid receptor agonist WIN 55,212-2 (0.5 mg/kg s.c.), alone or in combination with carbon monoxide, on extracellular glutamate levels in primary rat cerebral cortical neuronal cultures, were investigated. Dam weight gain, pregnancy length and litter size at birth were not affected by prenatal treatment with WIN 55,212-2 and carbon monoxide alone or in combination. Basal and K(+)-evoked extracellular glutamate levels were reduced in cortical cultures from pups born to mothers exposed to WIN 55,212-2 and carbon monoxide alone or in combination compared to cultures from rats born to vehicle-treated mothers. In cultures obtained from rats exposed to vehicle or carbon monoxide alone during gestation, WIN 55,212-2 (0.01-100 nM) increased extracellular glutamate levels, displaying a bell-shaped concentration-response curve. In cultures from rats born to mothers exposed to WIN 55,212-2 alone or in combination with carbon monoxide the WIN 55,212-2 ( 1 nM)-induced increase in extracellular glutamate levels was lower than that observed in cultures from rats born to vehicle-treated mothers and similar at those observed at 10 and 100 nM concentrations. The selective CB1 receptor antagonist SR141716A (10 nM) counteracted the WIN 55,212-2-induced increase in extracellular glutamate levels in cultures exposed to vehicle or carbon monoxide during gestation, but failed to antagonise it in cultures from rats born to mothers exposed to WIN 55,212-2 alone or in combination with carbon monoxide. These findings provide evidence that prenatal exposure to the cannabinoid receptor agonist WIN 55,212-2 and carbon monoxide, alone or in combination, is associated with an impairment in cortical glutamatergic transmission. It could be speculated that such detrimental effects might be involved in the reported deficit in learning and memory associated with prenatal marijuana exposure.

Acute exposure to methylmercury at two developmental windows: focus on neurobehavioral and neurochemical effects in rat offspring.

The neurobehavioral and neurochemical effects produced by prenatal methylmercury exposure (8 mg/kg, gestational-days 8 or 15), were investigated in rats. On postnatal day 40, animals exposed to methylmercury and tested in the open field arena, showed a reduction in the number of rearings, whereas the number of crossings and resting time was not altered with respect to the age-matched control rats. The methylmercury-exposed groups showed a lower level of exploratory behavior as well as an impairment in habituation and working memory when subjected to the novel object exploration task. The neophobia displayed by methylmercury-exposed rats is unlikely to be attributed to a higher degree of anxiety. Prenatal methylmercury exposure did not affect motor coordination or motor learning in 40-day-old rats subjected to the balance task on a rotating rod, and it did not impair the onset of reflexive behavior in pups screened for righting reflex, cliff aversion and negative geotaxis. In cortical cell cultures from pups exposed to methylmercury during gestation, basal extracellular glutamate levels were higher, whereas the KCl-evoked extracellular glutamate levels were lower than that measured in cultures from rats born to control mothers. In addition, a higher responsiveness of glutamate release to N-methyl-D-aspartic acid receptor activation was evident in cortical cell cultures from pups born from methylmercury-treated dams than in cultures obtained from control rats. The present results suggest that acute maternal methylmercury exposure induces, in rat offspring, subtle changes in short-term memory as well as in exploratory behavior. These impairments seem to be associated to alterations of cortical glutamatergic signaling.

New therapeutic strategies in perinatal stroke.

Perinatal stroke represents an important cause of severe neurological deficits that span the individual's lifetime, including delayed mental and motor development, epilepsy and major cognitive deficits. Most strokes occurring in term births, infants and children can be caused by thromboembolism from intracranial and extracranial vessels and are associated with a variety of risk factors such as birth asphyxia, cardiac diseases, blood disorders, maternal disorders, trauma. Animal models of perinatal stroke have been developed to examine the nature and the time course of the events occurring after the ischemic insult and the possible therapeutic strategies useful in reducing ischemic damage. The present article addresses the potential pharmacological treatments targeting the inflammatory process and apoptotic cell death, with a specific emphasis on the emerging role of statins as neuroprotective agents in perinatal stroke. As a prelude, we will also review advances in our understanding on the mechanisms underlying the hypoxic-ischemic reperfusion injury in the newborn.

Simvastatin protects against long-lasting behavioral and morphological consequences of neonatal hypoxic/ischemic brain injury.

BACKGROUND AND PURPOSE: Recent studies suggest that statins (3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors) not only reduce the incidence of stroke by lowering cholesterol levels but may also exert neuroprotective effects via a mechanism not related to their lipid-lowering effect. Despite the growing body of evidence, however, the neuroprotective effect of statins in stroke is still controversial. Herein, we studied whether a prophylactic administration of simvastatin (Sim) provides significant protection against brain damage, and we sought to determine its long-lasting behavioral consequences in a neonatal model of hypoxia/ischemia. METHODS: Newborn male rats were injected daily from postnatal days 1 to 7 with activated Sim (20 mg/kg) or an equivalent volume of vehicle. On postnatal day 7, the rats were subjected to ligation of the right common carotid artery, followed by 3 hours of hypoxia or by sham operation. The neuroprotective effect of Sim was evaluated after the rats had achieved adulthood by using a battery of behavioral tests and histological analysis. RESULTS: Sim-treated ischemic rats performed the circular water maze, the radial arm maze, and the multiple-choice water maze significantly better than did vehicle-treated ischemic rats. Furthermore, in contrast to the ischemic rats, hypoxia/ischemia-injured rats pretreated with Sim were not hyperactive at weaning and showed less behavioral asymmetry. Consistently, it was found that brain damage was significantly attenuated. CONCLUSIONS: These findings indicate that prophylactic administration of statins may provide a potential neuroprotective strategy leading to an improvement in functional outcome in ischemic stroke. However, toxicity concern must be addressed before these agents can be directed to the asphyxiated fetus or newborn.

Autoradiographic localization of [3H]thiocolchicoside binding sites in the rat brain and spinal cord.

Thiocolchicoside is used in humans as a myorelaxant drug with anti-inflammatory and analgesic activity. Recently we established the experimental conditions that allowed the identification of [3H]thiocolchicoside binding sites in synaptic membranes of rat spinal cord and cerebral cortex. The pharmacological characterization of these sites indicated that GABA and several of its agonists and antagonists, as well as strychnine, were able to interact with [3H]thiocolchicoside binding in a dose-dependent manner and with different affinities. In order to gain more insight into the nature and the anatomical distribution of the binding sites labeled by [3H]thiocolchicoside, in the present study we examined the localization of these sites on parasagittal and coronal sections of the rat brain and spinal cord, respectively, using receptor autoradiography. In the spinal cord an intense signal was observed in the gray matter, with the highest density occurring in the superficial layers of the dorsal horns. Strychnine completely displaced [3H]thiocolchicoside binding, whereas GABA only partially removed the radioligand from its binding sites. In the brain, specific binding occurred in several areas and was displaced by both GABA and strychnine. The distribution of [3H]thiocolchicoside binding sites in brain sections, however, did not match that found for [3H]muscimol. Furthermore, cold thiocolchicoside was not able to completely displace [3H]muscimol binding, and showed a different efficacy in the various areas labeled by the radioligand. We conclude that thiocolchicoside may interact with a subpopulation of GABA(A) receptors having low-affinity binding sites for GABA. Furthermore, the observed sensitivity to strychnine in the spinal cord indicates an interaction also with strychnine-sensitive glycine receptors, suggesting that the pharmacological effects of thiocolchicoside may be the result of its interaction with different receptor populations.

The time of tumor cell division and death depends on the site of growth.

We show here, for the first time, in two very different murine tumors, a mammary one (ectoderm) and a lung one (endoderm), that: tumors have day/night differences of spontaneous apoptosis additional to the well-known circadian rhythm of mitosis. The times of maximal and minimal mitosis and apoptosis changed for a tumor cell line when growing in different organs (as metastasis) or anatomical sites. Both tumor lines, have identical circadian curves when growing in a specific organ or anatomical site. The peaks of apoptosis match with the valleys of mitosis and vice versa.

Long-lasting behavioral alterations following a hypoxic/ischemic brain injury in neonatal rats.

The characterization of motor and cognitive dysfunctions following a neonatal ischemic injury is a prerequisite to investigate putative pharmacological interventions. To this end, in the present study, we evaluated the long-lasting behavioral alterations occurring after a hypoxic/ischemic injury obtained by the combination of monolateral carotid ligation and exposure to 8% oxygen for 3 h in 7-day-old rats. These animals show a different degree of damage in the side ipsilateral to the occluded artery. Motor coordination, tested both before and after weaning, was not affected, whereas spontaneous activity was increased at weaning but not in the adult age. When tested in an open field after apomorphine administration, most ischemic animals showed a marked turning behavior ipsilateral to the lesioned side. They also had a reduced rate of spontaneous alternation and a marked tendency to visit the arm of the T-maze ipsilateral to the lesion. Injured rats were deficient in performing water maze and T-maze acquisition tests but, when evaluated in a passive avoidance paradigm, no difference from controls was observed. These data indicate that an ischemic insult in neonatal rats causes long-lasting learning deficits and motor behavior asymmetry. These behavioral alterations may represent a useful endpoint for studying the efficacy of potential pharmacological treatments that may improve the behavioral consequences of a perinatal hypoxic/ischemic insult in humans.

[Signaling pathways regulating the expression of proteases during tumor progression]. / Vias de señalizacion que regulan la expresion de proteasas durante la progresión tumoral.

Deregulation of several signaling pathways have been found to be critical for the development of different types of tumors, both in transgenic and spontaneous models. The role of proteases and adhesion molecules during the early stages of tumor progression induced by oncogenes in epithelial and mesenchymal tumors has remained relatively unexplored. This review summarizes recent work showing that different but overlapping signaling effector modules (PKC, v-Ras-RalA-PLD1 or v-Src-RalA-PLD1) induce changes in the production of proteases (uPA and MMPs) and adhesion molecules (fibronectin, CD44, beta 1-integrin) in normal epithelial or mesenchymal cell lines, associated with tumor development in vivo. Overexpression of PKC gamma in normal mammary epithelial cells or of v-Src and v-Ras in NIH3T3 fibroblasts induced in all cases overproduction of uPA and MMPs and a tumorigenic phenotype. Proteases production and tumorigenicity in transformed NIH3T3 cells were dependent on the GTPase RalA. In contrast to the common outcome in protease production by the different tumor promoting stimuli, fibronectin production was high in PKC-overexpressing mammary epithelial cells and it was organized into a rich fibrillar matrix, while oncogene transformed fibroblasts displayed reduced fibronectin production and a total loss of FN fibrillogenesis, an effect also dependent on RalA. These results show that protease overexpression is a common denominator in the acquisition of a malignant phenotype both in mesenchymal and epithelial cells. In contrast there is a dramatic difference in the expression and function of adhesion molecules like fibronectin between these two cell types, suggesting different regulatory roles for this glycoprotein during tumor progression, in cells of different tissular origin.