Compliance with recommended preventive behaviours and restrictions for Covid-19: an exploratory analysis of Italians' attitudes.

BACKGROUND AND AIM: as a reaction to the COVID-19 pandemic, countries all over the world have undertaken wide-scale measures to prevent and limit the spread of the virus. Suggested preventative measures mainly included "lockdown", social distancing, wearing facemasks, and vaccinations. The success of these measures was widely dependent on the cooperation of citizens. However, people reacted differently to the several types of restrictions and recommendations. Even if the majority followed the rules, others ignored them. This study aims to investigate the reasons for the compliance or violation of the rules developed to fight against the COVID-19 pandemic in Italy. METHODS: to answer the research question, the analysis of two different surveys conducted on a representative sample of Italians (N=2000) were conducted and analysed through descriptive statistics. RESULTS: the data collection agreed with published literature. Compliance with rules during emergencies followed diligence and altruistic patterns. Fear of sanctions did not seem to work in relation to rules compliance during emergency situations. The lack of clarity of regulations in terms of complexity or constant changes led to non-compliance even intervening as a neutralization technique. CONCLUSIONS: government's fear-based interventions did not seem to work since Italians tended to adhere to the rules primarily out of respect for legitimate authority. Future research should focus more on the topic of trust in institutions in emergency situations with the aim of highlighting the key points for successful governance, also in terms of rules compliance.

Monolayer platform to generate and purify primordial germ-like cells in vitro provides insights into human germline specification.

Generating primordial germ cell-like cells (PGCLCs) from human pluripotent stem cells (hPSCs) advances studies of human reproduction and development of infertility treatments, but often entails complex 3D aggregates. Here we develop a simplified, monolayer method to differentiate hPSCs into PGCs within 3.5 days. We use our simplified differentiation platform and single-cell RNA-sequencing to achieve further insights into PGCLC specification. Transient WNT activation for 12 h followed by WNT inhibition specified PGCLCs; by contrast, sustained WNT induced primitive streak. Thus, somatic cells (primitive streak) and PGCLCs are related-yet distinct-lineages segregated by temporally-dynamic signaling. Pluripotency factors including NANOG are continuously expressed during the transition from pluripotency to posterior epiblast to PGCs, thus bridging pluripotent and germline states. Finally, hPSC-derived PGCLCs can be easily purified by virtue of their CXCR4+PDGFRA-GARP- surface-marker profile and single-cell RNA-sequencing reveals that they harbor transcriptional similarities with fetal PGCs.

Virtual reality rehabilitation program on executive functions of children with specific learning disorders: a pilot study.

Background: The application of Virtual Reality (VR) in the field of rehabilitation has been widely studied, because it has already proven to be an effective intervention for a variety of physical and cognitive conditions. Nevertheless, its application in pediatric rehabilitation is more recent. This pilot study aims to examine whether a VR-rehabilitation program may have positive effects on the Executive Functions (EFs) of children with Specific Learning Disorders (SLD). Materials and methods: Twenty-four children with diagnosis of SLD participated to the study (range 7-11 years) and performed the VR-training across 6 weeks in the CARE Lab, that was designed with appropriate structural measures and ad hoc fittings, to hide the sophisticated technology necessary to allow the child to experience a rehabilitative setting with recreational and semi-immersive features. Children were evaluated across three main time-points: T0, assessment of cognitive level and EFs immediately before the start of the intervention; T1, assessment of EFs immediately after the end of VR intervention; T2, follow-up of EFs after 6 months from the end of the VR intervention. The rehabilitation programs were customized according to clinical needs and/or single patient's characteristics, proposing different games with variable complexity levels. Results: Results showed that scores for visual attention, inhibition, flexibility, and planning abilities were significantly higher than before the intervention, and the most part of these ameliorations were maintained after 6 months. Conclusion: These findings provide important inputs for the development of new innovative rehabilitation interventions for children with SLD that must be founded in ecological and evidence-based approaches.

Antimicrobial Resistance Patterns of Enterobacter cloacae and Klebsiella aerogenes Strains Isolated from Clinical Specimens: A Twenty-Year Surveillance Study.

We retrospectively analyzed the antimicrobial data of Enterobacter spp. strains isolated from hospitalized subjects and outpatients over 20 years (2000-2019). A total of 2277 non-duplicate Enterobacter spp. isolates, 1037 from outpatients (45%) and 1240 from hospitalized subjects (55%), were retrieved. Most of samples are infections of the urinary tract. Considering Enterobacter aerogenes, now classified as Klebsiella aerogenes, and Enterobacter cloacae, representing more than 90% of all isolates, except for aminoglycosides and fluroquinolones, which showed significant antibiotic decreasing trends (p < 0.01), none of the other antimicrobial agents tested showed significant changes in both groups (p > 0.05). Conversely, there was a significant increasing resistance trend for fosfomycin (p < 0.01), among both community and hospital-related subjects, most probably owing to uncontrolled and improper usage. Surveillance studies on antibiotic resistance at the local and regional level are required to detect new resistance mechanisms, reduce inappropriate antimicrobial consumption, and increase the focus on antimicrobial stewardship.

Training Ethical Competence in a World Growing Old: A Multimethod Ethical Round in Hospital and Residential Care Settings.

Ethical challenges are traditionally described in a negative light, even though moral conflict can express the individual ability to perceive when something is not working and promote change. The true question, therefore, is not to how to silence moral conflict but how to educate it. Although the need for ethical support of health- and social-care professionals in elderly care is clearly perceived, there is no universal method for providing effective interventions. The authors hypothesize that adequate training sessions can help care professionals enhance this skill, once clear goals and specific educational techniques are set. This research tests the hypothesis on twenty care professionals working in acute and residential care settings for the elderly, building on the ethics round method. Mixed methods drawn from literature and the experience of educators were adapted to meet different educational goals. Moral issues can hardly be removed from a context characterized by increasing demand and decreasing resources, but they can be recognized and addressed with common efforts, a critical attitude, and a growth mindset. Enhancing these skills in qualified workers can help them accept the reality of work, release pressure, and identify common team goals. Introducing these skills before graduation can help future workers avoid unreal expectations and reduce frustration and early job quit rates.

The concept of vulnerability in aged care: a systematic review of argument-based ethics literature.

BACKGROUND: Vulnerability is a key concept in traditional and contemporary bioethics. In the philosophical literature, vulnerability is understood not only to be an ontological condition of humanity, but also to be a consequence of contingent factors. Within bioethics debates, vulnerable populations are defined in relation to compromised capacity to consent, increased susceptibility to harm, and/or exploitation. Although vulnerability has historically been associated with older adults, to date, no comprehensive or systematic work exists on the meaning of their vulnerability. To fill this gap, we analysed the literature on aged care for the meaning, foundations, and uses of vulnerability as an ethical concept. METHODS: Using PRISMA guidelines, we conducted a systematic review of argument-based ethics literature in four major databases: PubMed, Embase®, Web of Science™, and Philosopher's Index. These covered biomedical, philosophy, bioethical, and anthropological literature. Titles, abstracts, and full texts of identified papers were screened for relevance. The snowball technique and citation tracking were used to identify relevant publications. Data analysis and synthesis followed the preparatory steps of the coding process detailed in the QUAGOL methodology. RESULTS: Thirty-eight publications met our criteria and were included. Publication dates ranged from 1984 to 2020, with 17 publications appearing between 2015 and 2020. Publications originated from all five major continents, as indicated by the affiliation of the first author. Our analyses revealed that the concept of vulnerability could be distinguished in terms of basic human and situational vulnerability. Six dimensions of older adults' vulnerability were identified: physical; psychological; relational/interpersonal; moral; sociocultural, political, and economic; and existential/spiritual. This analysis suggested three ways to relate to older adults' vulnerability: understanding older adults' vulnerability, taking care of vulnerable older adults, and intervening through socio-political-economic measures. CONCLUSIONS: The way in which vulnerability was conceptualised in the included publications overlaps with distinctions used within contemporary bioethics literature. Dimensions of aged care vulnerability map onto defining features of humans, giving weight to the claim that vulnerability represents an inherent characteristic of humans. Vulnerability is mostly a value-laden concept, endowed with positive and negative connotations. Most publications focused on and promoted aged care, strengthening the idea that care is a defining practice of being human.

Levels of Moral Distress among Health Care Professionals Working in Hospital and Community Settings: A Cross Sectional Study.

Moral distress is a concern for all healthcare professionals working in all care settings. Based on our knowledge, no studies explore the differences in levels of moral distress in hospital and community settings. This study aims to examine the level of moral distress among healthcare professional working in community or hospital settings and compare it by demographic and workplace characteristics. This is a cross-sectional study. All the professionals working in the hospitals or community settings involved received personal e-mail invitations to participate in the study. The Moral Distress Thermometer was used to measure moral distress among healthcare professionals. Before data collection, ethical approval was obtained from each setting where the participants were enrolled. The sample of this study is made up of 397 healthcare professionals: 53.65% of the sample works in hospital setting while 46.35% of the sample works in community setting. Moral distress was present in all professional groups. Findings have shown that nurses experienced level of moral distress higher than other healthcare professionals (mean: 4.91). There was a significant differences between moral distress among different professional categories (H(6) = 14.407; p < 0.05). The ETA Coefficient test showed significant variation between healthcare professionals working in community and in hospital settings. Specifically, healthcare professionals who work in hospital experienced a higher level of moral distress than those who work in community settings (means 4.92 vs. means 3.80). The results of this study confirm that it is imperative to develop educational programs to reduce moral distress even in those settings where the level perceived is low, in order to mitigate the moral residue and the crescendo effect.

Moral Distress in Community and Hospital Settings for the Care of Elderly People. A Grounded Theory Qualitative Study.

Background: Moral distress has frequently been investigated in single healthcare settings and concerning a single type of professional. This study aimed to describe the experience of moral distress in all the types of professionals providing daily care to elderly patients and residents. Methods: The Grounded Theory approach, developed by Corbin and Strauss, was used. This study included participants from hospital and nursing homes of northern Italy. Purposive and theoretical sampling was used. Between December 2020 and April 2021, semi-structured interviews were conducted. Results: Thirteen participants were included in the study. Four categories were derived from the data: talking and listening, care provider wellbeing, decision making, protective factors, and potential solutions. The core category identified was "sharing daily". Interviewees confirm how hard it may be to communicate to the elderly, but at the same time, how adequate communication with the leader is a protective factor of moral distress. They also confirm how communication is key to managing or downsizing misunderstandings at all levels. Findings highlight the scarcity of operators as a fundamental trigger of moral distress. Conclusions: Many determinants of this phenomenon lie behind the direct control of professionals, but education can help them learn how to prevent, manage, or downsize the consequences.

Ethical Problems and Moral Distress in Primary Care: A Scoping Review.

BACKGROUND: Since 1997, nursing ethics research has focused on solving ethical dilemmas, enhancing decision-making strategies, and introducing professional education. Few studies describe the triggers of ethical dilemmas among primary care nurses. The aim of this study was to explore the moral distress and ethical dilemmas among primary care nurses. METHODS: A scoping review was performed following Arskey and O'Malley's framework. PubMed, CINAHL, PsycINFO, Embase, and Scopus were searched systematically to retrieve relevant titles and abstracts. A temporal filter was applied to focus on the most recent literature (years of 2010-2020). The research was completed on 17 November 2020. RESULTS: Of 184 articles retrieved, 15 were included in the review. Some (n = 7) studies had a qualitative design, and the most productive country was Brazil (n = 7). The total number of nurses involved in quantitative studies was 1137 (range: 36-433); the total number of nurses involved in qualitative studies was 144 (range: 7-73). Three main focus areas were identified: (a) frequent ethical conflicts and moral distress episodes among nurses working in primary care settings; (b) frequent moral distress measures here employed; (c) coping strategies here adopted to prevent or manage moral distress. CONCLUSION: Further research is needed to examine the differences between moral distress triggers and sources of ethical dilemmas among the different care environments, such as primary care and acute care settings.

Growth disadvantage associated with centrosome amplification drives population-level centriole number homeostasis.

The centriole duplication cycle normally ensures that centriole number is maintained at two centrioles per G1 cell. However, some circumstances can result in an aberrant increase in centriole number-a phenotype that is particularly prevalent in several types of cancer. Following an artificial increase in centriole number without tetraploidization due to transient overexpression of the kinase PLK4, human cells return to a normal centriole number during the proliferation of the population. We examine the mechanisms responsible for this return to normal centriole number at the population level in human retinal pigment epithelial cells. We find that the return to normal centriole number in the population of induced cells cannot be explained by limited duplication of centrioles, instability of extra centrioles, or by grossly asymmetric segregation of extra centrioles in mitosis. However, cells with extra centrioles display heterogenous phenotypes including extended cell cycle arrest, longer interphase durations, and death, which overall results in a proliferative disadvantage relative to normal cells in the population. Although about half of cells with extra centrioles in a population were able to divide, the extent of the disadvantages conferred by other fates is sufficient to account for the observed rate of return to normal centriole number. These results suggest that only under conditions of positive selection for cells with extra centrioles, continuous generation of such centrioles, or alleviation of the disadvantageous growth phenotypes would they be maintained in a population.

Instruments to assess moral distress among healthcare workers: A systematic review of measurement properties.

BACKGROUND: An increasing number of professionals are challenged by the evolution of modern healthcare and society, often characterized by more expectations with reduced resources. Moral distress is among the psychophysical conditions now most under investigation in order to improve the wellbeing of professionals, the sustainability of organizations and the quality of care. Over the last decades, several instruments have been developed to assess the frequency or intensity of moral distress in different studies. Yet, there has not been, so far, a systematic assessment of the qualitative properties of the various instruments measuring moral distress in healthcare workers based on a universally accepted standardized framework. OBJECTIVE: (1) To identify all instruments for the measurement of moral distress available in recent literature; (2) to evaluate the evidence regarding their measurement properties; (3) to facilitate the selection of the most appropriate instrument to be adopted in practice and research. DESIGN: Systematic literature review. DATA SOURCES: PubMed, CINAHL, and PyscINFO. REVIEW METHODS: The COnsensus-based Standards for the selection of health Measurement INstruments checklist was used to evaluate the methodological quality of the identified studies. The quality of measurement properties of each instrument was evaluated using Terwee's quality criteria. RESULTS: Among the 1268 studies found, 88 full-text articles evaluated moral distress adopting different tools. Thirty two of them had a methodological design. The measurement instruments assessed in this review are different in terms of targeted population and items. The instruments were then divided into two main categories: (1) Corley's instruments on moral distress (Moral distress scale and Moral Distress Scale - Revised) and (2) instruments not directly derived from Corley's moral distress theory (Moral Distress thermometer, Moral Distress Risk Scale, Ethical Stress Scale or Moral Distress in Dementia Care Survey). The first set is the most frequently studied and used in different clinical settings and healthcare populations. A variety of psychometric properties have been evaluated for each instrument, revealing different qualities in the methodology used. CONCLUSIONS: Several instruments assessing moral distress in healthcare workers have been identified and evaluated in this systematic review. Based on the criteria used here, Corley's instruments on moral distress seems to be the most useful and most appropriate to the clinical setting for practice and research purposes. TWEETABLE ABSTRACT: The aim of this systematic review was to identify the instruments measuring moral distress now available in the literature, in order to (1) assess the evidence about their measurement properties, (2) support the selection of the most appropriate instrument to be used in practice and research.

Phosphorylation status of thymidine kinase 1 following antiproliferative drug treatment mediates 3'-deoxy-3'-[18F]-fluorothymidine cellular retention.

BACKGROUND: 3'-Deoxy-3'-[18F]-fluorothymidine ([18F]FLT) is being investigated as a Positron Emission Tomography (PET) proliferation biomarker. The mechanism of cellular [18F]FLT retention has been assigned primarily to alteration of the strict transcriptionally regulated S-phase expression of thymidine kinase 1 (TK1). This, however, does not explain how anticancer agents acting primarily through G2/M arrest affect [18F]FLT uptake. We investigated alternative mechanisms of [18F]FLT cellular retention involving post-translational modification of TK1 during mitosis. METHODS: [18F]FLT cellular retention was assessed in cell lines having different TK1 expression. Drug-induced phosphorylation of TK1 protein was evaluated by MnCl2-phos-tag gel electrophoresis and correlated with [18F]FLT cellular retention. We further elaborated the amino acid residues involved in TK1 phosphorylation by transient transfection of FLAG-pCMV2 plasmids encoding wild type or mutant variants of TK1 into TK1 negative cells. RESULTS: Baseline [18F]FLT cellular retention and TK1 protein expression were associated. S-phase and G2/M phase arrest caused greater than two-fold reduction in [18F]FLT cellular retention in colon cancer HCT116 cells (p<0.001). G2/M cell cycle arrest increased TK1 phosphorylation as measured by induction of at least one phosphorylated form of the protein on MnCl2-phos-tag gels. Changes in [18F]FLT cellular retention reflected TK1 phosphorylation and not expression of total protein, in keeping with the impact of phosphorylation on enzyme catalytic activity. Both Ser13 and Ser231 were shown to be involved in the TK1 phosphorylation-modulated [18F]FLT cellular retention; although the data suggested involvement of other amino-acid residues. CONCLUSION: We have defined a regulatory role of TK1 phosphorylation in mediating [18F]FLT cellular retention and hence reporting of antiproliferative activity, with implications especially for drugs that induce a G2/M cell cycle arrest.

A novel radiotracer to image glycogen metabolism in tumors by positron emission tomography.

The high rate of glucose uptake to fuel the bioenergetic and anabolic demands of proliferating cancer cells is well recognized and is exploited with (18)F-2-fluoro-2-deoxy-d-glucose positron emission tomography ((18)F-FDG-PET) to image tumors clinically. In contrast, enhanced glucose storage as glycogen (glycogenesis) in cancer is less well understood and the availability of a noninvasive method to image glycogen in vivo could provide important biologic insights. Here, we demonstrate that (18)F-N-(methyl-(2-fluoroethyl)-1H-[1,2,3]triazole-4-yl)glucosamine ((18)F-NFTG) annotates glycogenesis in cancer cells and tumors in vivo, measured by PET. Specificity of glycogen labeling was demonstrated by isolating (18)F-NFTG-associated glycogen and with stable knockdown of glycogen synthase 1, which inhibited (18)F-NFTG uptake, whereas oncogene (Rab25) activation-associated glycogen synthesis led to increased uptake. We further show that the rate of glycogenesis is cell-cycle regulated, enhanced during the nonproliferative state of cancer cells. We demonstrate that glycogen levels, (18)F-NFTG, but not (18)F-FDG uptake, increase proportionally with cell density and G1-G0 arrest, with potential application in the assessment of activation of oncogenic pathways related to glycogenesis and the detection of posttreatment tumor quiescence.

Synthesis and evaluation of nucleoside radiotracers for imaging proliferation.

INTRODUCTION: Uncontrolled proliferation is a fundamental characteristic of cancer, and consequently, imaging of tumor proliferative status finds interest clinically both as a diagnostic tool and for evaluation of response to treatment. Positron emission tomography (PET) radiotracers based on a nucleoside core, such as 3'-[18F]fluoro-3'-deoxythymidine ([18F]FLT), have been extensively studied for this purpose. However, [18F]FLT suffers from poor DNA incorporation leading to occasional poor correlation of [18F]FLT tumor uptake with other proliferation indicators such as Ki-67 immunostaining. METHODS: N3-((1-(2-[18F]fluoroethyl)-1H-[1,2,3]-triazol-4-yl)methyl)thymidine ([18F]2) and N3-((1-(2-[18F]fluoroethyl)-1H-[1,2,3]-triazol-4-yl)methyl)-4'-thio-ß-thymidine ([18F]3) were synthesized by click chemistry from [18F]fluoroethyl azide and by direct nucleophilic substitution of a tosylate precursor. Metabolic stability and phosphorylation potential of the radiotracers were evaluated in vitro and compared to [18F]FLT. Further, metabolic stability and biodistribution analysis of [18F]2 and [18F]3 were evaluated in vivo. RESULTS: Stable isotope standards and radiochemistry precursors were synthesized by modification of existing literature procedures. [18F]2 and [18F]3 were synthesized in a radiochemical yield of 8%-12% (end of synthesis, non-decay corrected). Both nucleosides were stable to metabolic degradation by thymidine phosphorylase, and in vivo stability analysis showed only one metabolite for [18F]3. No phosphorylation of [18F]2 could be detected in HCT116 cell homogenates, and in the same assay, only minor (∼8%) phosphorylation of [18F]3 was observed. Biodistribution in Balb/c mice indicated rapid clearance for [18F]2 and [18F]3 to a lesser extent. CONCLUSIONS: The favorable biodistribution and metabolic profile of [18F]3 warrant further investigation as a next-generation PET proliferation marker.

Novel imatinib derivatives with altered specificity between Bcr-Abl and FMS, KIT, and PDGF receptors.

Imatinib is a clinically important ATP analogue inhibitor that targets the tyrosine kinase domain of the intracellular Abl kinase and the PDGF receptor family. Imatinib has revolutionised the treatment of chronic myeloid leukaemia, which is caused by the oncogene Bcr-Abl and certain solid tumours that harbor oncogenic mutations of the PDGF receptor family. As a leading kinase inhibitor, imatinib also provides an excellent model system to investigate how changes in drug design impact biological activity, which is an important consideration for rational drug design. Herein we report a new series of imatinib derivatives that in general have greater activity against the family of PDGF receptors and poorer activity against Abl, as a result of modifications of the phenyl and N-methylpiperazine rings. These new compounds provide a platform for further drug development against the therapeutically important PDGF receptor family and they also provide insight into the engineering of drugs with altered biological activity.

Autonomy, responsibility and the Italian Code of Deontology for Nurses.

This article is a first assessment of the Italian Code of deontology for nurses (revised in 1999) on the basis of data collected from focus groups with nurses taking part in the Ethical Codes in Nursing (ECN) project. We illustrate the professional context in which the Code was introduced and explain why the 1999 revision was necessary in the light of changes affecting the Italian nursing profession. The most remarkable findings concern professional autonomy and responsibility, and how the Code is thought of as a set of guidelines for nursing practice. We discuss these issues, underlining that the 1999 Code represents a valuable instrument for ethical reflection and examination, a stimulus for putting the moral sense of the nursing profession into action, and that it represents a new era for professional nursing practice in Italy. The results of the analysis also deserve further qualitative study and future consideration.

Ethical codes in nursing practice: the viewpoint of Finnish, Greek and Italian nurses.

AIM: This paper is a report of a study exploring the use of ethical codes and obstacles to their use in nursing practice as perceived by Finnish, Greek and Italian nurses. BACKGROUND: In all European countries nurses are responsible for the well-being of patients, for their own technical and ethical competence and, for their own part, for the high standard of health care in society. These points illustrate the central content areas of nursing codes of ethics. Recent advances in medical technology have added to the complexity of nursing. Nurses today are increasingly confronted with ethical dilemmas, underlining the role and meaning of ethical codes in their decision-making. However, there is only very limited research literature on codes of ethics, their use in nursing practice and obstacles to their use. METHODS: Twenty-three focus group interviews were conducted in 2003 with a total of 138 Registered Nurses: 35 in Finland, 54 in Greece and 49 in Italy. The data were content analysed. FINDINGS: Two main categories emerged from our analysis of the use of ethical codes: (1) conscious and (2) unconscious use. Seven main categories described the obstacles to the use of ethical codes: (1) the codes themselves, (2) nurses themselves, (3) multiprofessional teamwork, (4) patients' family members, (5) the organization, (6) the nursing profession and (7) society/healthcare policy. Participants in all three countries were firmly committed to the values expressed in ethical nursing codes. Nonetheless, continued efforts are needed in all these countries to remove the remaining obstacles so that nursing care can be provided in keeping with the requirements of ethical codes. CONCLUSION: The use of codes is connected with the changes in nursing profession and in society at large. The core of nursing, however, has remained stable. Future studies should be conducted in order to generalize the findings to a broader population.

The value of nurses' codes: European nurses' views.

Nurses are responsible for the well-being and quality of life of many people, and therefore must meet high standards of technical and ethical competence. The most common form of ethical guidance is a code of ethics/professional practice; however, little research on how codes are viewed or used in practice has been undertaken. This study, carried out in six European countries, explored nurses' opinions of the content and function of codes and their use in nursing practice. A total of 49 focus groups involving 311 nurses were held. Purposive sampling ensured a mix of participants from a range of specialisms. Qualitative analysis enabled emerging themes to be identified on both national and comparative bases. Most participants had a poor understanding of their codes. They were unfamiliar with the content and believed they have little practical value because of extensive barriers to their effective use. In many countries nursing codes appear to be 'paper tigers' with little or no impact; changes are needed in the way they are developed and written, introduced in nurse education, and reinforced/implemented in clinical practice.

The human melanoma associated protein melanotransferrin promotes endothelial cell migration and angiogenesis in vivo.

Melanotransferrin is a member of the transferrin family, which is comprised of serum transferrin, lactoferrin and ovotransferrin, and is highly expressed on melanoma cells compared to normal melanocytes. Since melanoma is an highly vascularized tumour that expresses melanotransferrin at high levels, we tested purified recombinant melanotransferrin for its capability to induce angiogenesis in the chick chorioallantoic membrane. Macroscopic and microscopic evaluation of the vascular density demonstrated that melanotransferrin exerts an angiogenic response quantitatively similar to that elicited by fibroblast growth factor-2. Overexpression of vascular endothelial growth factor-receptor-2 was observed in newly formed vessels, suggesting that the angiogenic activity of melanotransferrin may depend on activation of endogenous vascular endothelial growth factor. In addition, when antibodies against vascular endothelial growth factor were included in the assay, the angiogenic response was inhibited by 50%. In a Boyden chamber assay purified recombinant melanotransferrin induced chemotactic migration of vascular cells, which was decreased in the the presence of anti-vascular endothelial growth factor antibodies suggesting an involvement of vascular endothelial growth factor present in endothelial cells also in this assay. However, melanotransferrin was found not to directly bind to integrin alphavbeta3 or the vascular endothelial growth factor-receptor-2 as assessed in a BlAcore assay. A possible correlation between vascularization occurring during melanoma progression and the expression of melanotransferrin and vascular endothelial growth factor was established by immunolocalization of the two factors in sections of melanoma at different clinical steps of melanoma progression. These latter data strongly imply that melanotransferrin may participate in the vascularization of solid tumours and that inhibition of melanotransferrin could form the basis for intervention in tumours which use this pathway.

Expression of the nerve growth factor receptors TrkA and p75NTR in the visual cortex of the rat: development and regulation by the cholinergic input.

Several lines of evidence have shown that nerve growth factor (NGF), the progenitor of the neurotrophin family of growth factors, plays a fundamental role in the developmental plasticity of the rat visual cortex. However, the expression of NGF receptors (NGFRs) TrkA and p75(NTR) and the possible sites of NGF action in the visual cortex remain to be elucidated so far. Using a highly sensitive ECL immunoblot analysis, we have been able to show, in the present study, that the TrkA protein is expressed in the rat visual cortex and that it is developmentally upregulated during the critical period for cortical plasticity. In contrast, the expression level of the low-affinity NGF receptor p75(NTR) seems to remain nearly constant throughout development. In the analysis of possible pathways involved in the regulation of NGFR expression, we found that neither blockade of the visual input nor NGF administration to the visual cortex resulted in a modulation of NGFR levels of expression. On the other hand, the selective destruction of cholinergic afferents to the visual cortex caused a dramatic, but not complete, reduction of the cortical NGFRs, which suggests that these receptors are located on cholinergic terminals predominantly. At the functional level, we found that, after the elimination of the cholinergic afferents to the visual cortex, the NGF-induced increase of both acetylcholine and glutamate release from cortical synaptosomes was strongly impaired. These results indicate that the cholinergic input is an important mediator of visual cortex responsiveness to NGF action.