Clinical profile and outcome of cardiomyopathies in infants and children seen at a tertiary centre

INTRODUCTION

Due to their rare prevalence and marked heterogeneity, pediatric cardiomyopathies (CMPs) are little known and scarcely reported. We report the etiology, clinical profile and outcome of a consecutive cohort of children diagnosed with CMP and followed at Meyer Children's Hospital over a decade.

PATIENTS AND METHODS

We retrospectively reviewed patients consecutively referred from May 2008 to May 2019 for pediatric onset CMP (<18 years). Heart disease caused by arrhythmic disorders, toxic agents, rheumatic conditions and maternal disease were excluded.

RESULTS

We enrolled 110 patients (65 males), diagnosed at a median age of 27 [4-134] months; 35% had an infant onset (<1 year of age). A positive family history was more often associated with childhood-onset (38.8%). Hypertrophic cardiomyopathy (HCM; 48 patients) was the most frequent phenotype, followed by dilated cardiomyopathy (DCM; 35 patients). While metabolic and idiopathic etiologies were preponderant in infants, metabolic and sarcomeric diseases were most frequent in the childhood-onset group. Major adverse cardiac events (MACE) occurred in 31.8% of patients, including hospitalization for acute heart failure in 25.5% of patients, most commonly due to DCM. Overall, the most severe outcomes were documented in patients with metabolic diseases.

CONCLUSIONS

In a consecutive cohort of pediatric patients with CMP, those with infantile onset and with a metabolic etiology had the worst prognosis. Overall, MACE occurred in 41% of the entire population, most commonly associated with DCM, inborn errors of metabolism and genetic syndromes. Systematic NGS genetic testing was critical for etiological diagnosis and management.

Bridging Epidemiological Data with Features of the Urban Context: An experience of Urban Public Health within the City of Milan, Italy

Referring to the Research Project “Enhancing Healthcare and Well-Being Through the Potential of Big Data: An Integration of Survey, Administrative, and Open Data to Assess Health Risk in the City of Milan with Data Science” the Authors present preliminary results regarding a survey distributed to a sample of citizens across all neighborhoods of Milano city. This survey sought to collect data regarding health risk factors of this population, including both individual (e.g. socio-demographic characteristics, behaviors, etc.) and community (e.g. environmental/morphological features, available social services, etc.) data. A digital survey was designed to collect information on the health conditions, risk factors, and lifestyle characteristics of a representative sample of the Milanese population at the neighborhood level, with reference to the census tracts and Local Identity Units (NIL). Collected survey data are entered into a system containing corresponding individual health information acquired from the Local Health Authority databases, creating a synthesized information profile with each respondent's state of health, including existing conditions, health services used, and drug therapies. The disseminated survey was developed from comparisons with similar experiences at the national/international level and divided into 60 multiple choice questions (6 for Sociodemographic profile; 8 for Context of residence; 12 for Functional limitations; 25 for Behaviors and lifestyles; 9 for Access to health services). The data from urban analysis conducted on the NIL of the City of Milan are assessed with particular reference to the theme of bicycle-pedestrian accessibility (Walkability) in the urban context and repercussions on the adoption of Healthy Lifestyles. The models developed through this research are expected to provide critical insight for designing health promotion, health protection, and disease prevention interventions aimed both at individual and community level.

Evidence-informed health care infrastructures: test of SustHealthv2 tool on hospital pilot cases

Background

Healthcare facilities are important node of health systems and several scholars from Public Health and health service field highlighted that high quality and sustainable built environment is fundamental in providing high quality health care services. Nevertheless, most hospital buildings are obsolete, not adequate to contemporary organizational models; additionally, none of the existing quality improvement tools systematically evaluate the built environment. Therefore, the study develops an evidence-informed weighted multicriteria tool and tested it on two pilot case study.

Methods

Starting from previous literature reviews and scenario analysis, different indicators for hospital quality assessment have been grouped in 17 criteria and 3 macro areas, validated through semi-structured interviews and weighted with Multicriteria Simon Roy Figueras (MCDA-SRF) and Deck Card Method (DCM). The weighted tool SustHealthv2 has been tested on two medium sized hospital pilot case studies (H1 and H2) in northern Italy.

Results

The tool is composed by three macro areas: Social, Environmental and Organizational qualities respectively accounting for 22%, 29% and 49%. The application and test of the tool highlighted transversal criticalities such as Sustainable Accessibility (H1=0.04/0.16; H2=0.11/0.16), Sensitization and Education (H1=0.06/0.18; H2=0.10/0.18). The most recent case study (H1) was able to achieve higher scores in energy (0.15/0.0.19), waste management (0.07/0.07), as well as future proofing characteristics (0.20/0.23) compared to the older one. Overall H1 scored higher in all the macro areas reaching a total fulfillment of 72/100, while H2 scored 52/100.

Conclusions

The application of SustHealth v2 on operating health care facilities can support hospital management in defining strategic area of improvements and investments for hospital building renovation providing higher level of services to patients, users and staff.

Key messages

Built environment for healthcare needs systematic evaluation frameworks to improve and contribute to health service quality. SustHealth v2 is an evidence-informed multicriteria framework for hospital built environment sustainability and quality assessment from social, environmental and organizational perspective.

Validation Checklist for Massive Vaccination Centers

Abstract

Starting from the minimum requirements indicated by Lombardy Region, a validation checklist has been developed by experts in design, healthcare layout planning, hygiene and public health, planning and compliance, in order to provide managers of COVID-19 massive vaccination centers with a useful and easy-to-use tool to ensure quality, safety and efficiency of the different activities performed.

Reversible metamorphosis from Fe3O4 to FeO of epitaxial iron oxide films grown on the Fe-p(1 × 1)O surface

The reduction and oxidation of epitaxial Fe₃O₄ films grown by reactive deposition on a Fe-p(1 × 1)O surface have been investigated by means of Auger electron spectroscopy (AES), low energy electron diffraction (LEED) and scanning tunneling microcopy (STM). The as-grown iron oxide samples display a square LEED pattern with a lattice constant compatible with a p(1 × 1) bulk terminated Fe₃O₄(001) surface. STM topographic images of Fe₃O₄ are characterized by atomically flat terraces separated by highly oriented steps running along the (010) and (100) crystallographic directions of the substrate. Upon annealing at 800 K in an ultra-high vacuum, AES reveals that magnetite transforms to FeO. The sample exposes the (001) surface of the rock salt structure, with a lattice parameter close to that of bulk wüstite. The Fe₃O₄ phase can be recovered by oxidation at 10⁻⁶ mbar of molecular oxygen.

The reduction and oxidation of epitaxial Fe₃O₄ films grown by reactive deposition on a Fe-p(1 × 1)O surface have been investigated by means of surface science techniques.

Prevalence of adverse cardiovascular events in pediatric cardiomyopathies: an analysis of 110 patients followed at a long-standing tertiary care paediatric centre

Introduction

Pediatric cardiomyopathies (CMP) are disorders of the morphology and function of the heart, with a greater heterogeneity concerning etiology and clinical presentation than adult CMP. The assessment of etiology and genetic status is of paramount importance for prognosis, family screening, and therapeutic choices.

Purpose

To report clinical presentation, etiology, and outcome of a cohort of children diagnosed with CMP followed at tertiary care pediatric referral centre.

Methods

We retrospectively reviewed clinical, laboratory and imaging data of all patients referred to our cardiomyopathy centre from May 2008 to May 2019 for pediatric CMP (&lt;18 years). CMP due to arrhythmic disorders, toxic agents' exposure, rheumatic conditions and maternal disease (i.e. maternal diabetes) were excluded. Primary endpoint was a composite of major adverse cardiovascular events (MACE: cardiovascular death, heart failure [HF] hospitalization, arrhythmic events, need for surgery or heart transplant referral).

Results

We enrolled 110 patients (65 males, age at diagnosis 67±71 months). Hypertrophic cardiomyopathy (HCM, N=48, 44%) was most frequent, followed by dilated cardiomyopathy (DCM, N=35 32%) and left ventricular non-compaction phenotype (LVNC, N=12, 11%). Mixed phenotype (N=7, 6%) and restrictive cardiomyopathy (RCM, N=3, 3%) were less common. No cases of arrhythmogenic right ventricular cardiomyopathy (ARVC) were detected. Five genotype-positive patients presented with negative clinical phenotype. A diagnosis was confirmed in all patients; the most common was sarcomere disease (30%, N=33) followed by metabolic (28%,N=31) disease, genetic syndromes (11%, N=12), neuromuscular (7,3%, N=8) diseases, and post-myocarditis cases (4,5%,N=5). Twenty-one patients (19%) were identified as idiopathic. At referral, 4,5% of children presented with NYHA class III/IV.

At 35 [14–72] months, 4 (3.7%) patients required ICD implantation, 8 (7.4%) underwent cardiac surgery, and 1 (1%) underwent heart transplant. Furthermore, 28 (26%) patients required hospitalization due to acute HF, with DCM patients being at higher risk (p&lt;0.01), 7 (6.8%) experienced arrhythmic events and 4 (3.9%) had syncope. Overall, 13 (12%) died (7 with metabolic disorders, 3 with genetic syndromes, 1 with a sarcomeric mutation, 1 post myocarditis, and 1 idiopathic).

Conclusions

In our cohort, HCM was the most common cause of pediatric CMP followed by DCM and non-compaction. MACE were present in 41% of patients. While HCM had a less severe phenotype (characterized by a higher arrhythmic burden), DCM was characterized by a higher prevalence of HF hospitalizations. DCM, inborn errors in metabolism and genetic syndromes had the worst outcome in terms mortality and heart failure long term.

Widespread availability of genetic testing provides several benefits to the clinician, confirming diagnosis in ambiguous cases and defining etiology in order to guide management and identifying relatives at risk.

Figure 1

Funding Acknowledgement

Type of funding source: None

COVID-19 lockdown: housing built environment’s effects on mental health

Background

Since the World Health Organization (WHO) declared the coronavirus infectious disease 2019 (COVID-19) outbreak a pandemic on March 11th, severe 'lockdown' measures have been adopted by the Italian Government. For over two months of stay-at-home, houses became the only place where people slept, ate, worked, practiced sports, and socialized. As consolidated evidence exists on housing as a determinant of health, it is of great interest to explore the impact that COVID-19 response-related lockdown measures had on mental health and wellbeing.

Methods

We conducted a large web-based survey on 9261 subjects in Northern Italy, one of the Regions most heavily hit by the pandemic in Europe. Participants were recruited among university staff, faculty and students. The questions included socio-demographic features of the participants; international evaluation scales designed to recognize depressive-, anxiety- and sleep-related symptoms, impulsivity, quality of life; architectural parameters investigating housing physical characteristics.

Results

As emerges from our analysis poor housing is associated with increased risk of depressive symptoms during lockdown. In particular, living in apartments &lt; 60 m2, with poor quality view and indoor area is associated with, respectively, 1.31 (95CI), 1.368 (95CI), and 2.253 (95CI) time the risk of moderate/severe and severe depressive symptoms. Subjects reporting worsened working performance from home were over four times more likely to also report depression (OR = 4.28, 95%CI).

Conclusions

Our findings suggest housing played a major role in influencing people mental health and wellbeing during COVID-19 pandemic. We argue strengthened multi-interdisciplinary approach involving urban planning, public mental health, environmental health, epidemiology, and sociology, is needed to inform the planning implementation and monitoring of housing policies centered on population health.

Key messages

COVID-19 lockdown mitigation measures strongly impacted on Mental Health. Living in apartments &lt; 60 m2, with poor quality view and indoor area significatively increase the risk of moderate and severe depressive symptoms.

The challenges in training and education of hospital designers and planners

Background

The designed hospital environment is one of the most complex endeavors of work and there is a growing need of specialization. Scientific, technological and research developments and innovation along with new discoveries within health promotion and prevention strategies are increasingly requiring a multidisciplinary and interdisciplinary approach to the design and management of hospitals. Therefore, it is likely that the current professions will be replaced and flanked by more specialized ones.

Objectives

The scope of the paper is to display an overview of the current educational courses of the emerging Hospital Planner, referring to the worldwide available training courses (BSc, MSc, specialization and PhD courses) related to healthcare design. The focus relates to the fields of Medicine and Nursing sciences, Architecture and Engineering.

Results

A preliminary investigation has been conducted of websites and snowballing technique. The search was limited to active training programs and courses. Currently several institutions offer BSc, MSc courses and PhD programs in Healthcare Design, Environmental and Building Hygiene and Public Health. As well, there are several professional postgraduate courses either in classroom or using hybrid programs including webinars. Clemson University, USA and Ontario College of Art and Design University, Canada, offer a full MSc degree in Architecture and Health. In addition, there are several joint degree programs such as physician-engineer, physician-architect, nurse-architect or engineer.

Conclusions

From the preliminary study emerged a considerable number of international experiences addressing the topic of Hospital Planner training. Further in-depth investigations will examine the topic through questionnaires and interviews of the course organization, students' experiences, outcomes and professional careers, fields of interest and collaborations with other institutions.

Key messages

Hospital environments are the most complex field of work and require many years of specialization and multidisciplinarity and influence the quality of patient outcomes. The academic stream of the built environment is evolving toward proving specific multidisciplinary courses and hands-on experiences to support a degree in hospital planning, design and management.

Educational Challenges in Healthcare Design: Training Multidisciplinary Professionals for Future Hospitals and Healthcare

BACKGROUND

Healthcare environments are one of the most complex and demanding fields of work. Scientific, technological and research developments along with new discoveries within health promotion and prevention strategies are increasingly requiring a multidisciplinary and interdisciplinary approach. Therefore, it is likely that the current professions will need to be significantly adapted to accommodate new and more specialized roles.

OBJECTIVES

To present an overview of the current educational and training courses of the emerging professions, such as hospital planner, physician-engineer, doctor-architect, nurse-architect or engineer, we review the present global training courses (BSc, MSc, specialization and PhD courses) related to healthcare design focusing on the fields of Medicine and Nursing, Architecture and Engineering sciences.

RESULTS

The paper analyses the literature review and website analysis about active teaching programs and courses. Several academic institutions offer BSc, MSc and PhD degree programs in Healthcare Design, Environmental and Building Hygiene, and Public Health. In addition, there are several professional postgraduate courses, either in classroom, hybrid-based or online.

CONCLUSIONS

A considerable number of international training experiences addresses the topic of training multidisciplinary professionals. Further in-depth investigations are needed to examine the content, teaching format and impact of the courses, student outcomes and professional careers, fields of interest and the degree of collaborations with other institutions.

Evidence Based Hospital Design. A literature review of the recent publications about the EBD impact of built environment on hospital occupants' and organizational outcomes

INTRODUCTION

Healthcare facilities are complex infrastructures where different features from technological, social, clinical and architectural field interact. In modern healthcare systems there is a growing attention to the need of quality in terms of process and outcome, while the structural (physical) aspects are not often considered. Since the Nineties the theory of the Evidence Based Design (EBD) states that there is significant relationship between built environment and health related outcome.

OBJECTIVE

Aim of this paper is to investigate, in the recent scientific literature, which are the most important occupants' and organizational outcomes influenced by EBD hospital built environment qualities.

METHODOLOGY

A Literature Review based on Scopus and PubMed databases has been run in order to understand the existing situation in terms of hospital quality evaluation from the physical and architectural point of view and to highlight the current trends. The results of the different reviews, empirical studies and post Occupancy Evaluations have been analyzed according to Ulrich's EBD conceptual framework.

RESULTS

35 peer reviewed papers from the last 2 years were included. The methodologies adopted are very different and data are mainly collected through structured interviews or observations and elaborated with qualitative (33%), quantitative (26%) or mixed (41%) methodologies. The topic is mostly investigated in USA, Australia, Canada, UK and in the Scandinavian region; few contributions come also from Italy. Built environment variables that affect user's or organizational outcomes are mainly the Visual Environment (29%), the Audio Environment (20%) and the Patient Room Design (20%).

DISCUSSION AND CONCLUSION

The most recurrent outcomes found to be affected by the built environmental qualities are staff job satisfaction (n=11), patients' stress reduction (n=9), patients' satisfaction (n=6) and patients' fall reduction (n=6). Organizational outcomes are mentioned only two times. Although EBD is an old theory, the topic is both contemporary and relevant. Due to the diversity of the contributions and the limitations of the research, a deep comparison is challenging. Further investigation is necessary to deepen each of the variables identified.

Assessment of climate change effects on mountain ecosystems through a cross-site analysis in the Alps and Apennines

Mountain ecosystems are sensitive and reliable indicators of climate change. Long-term studies may be extremely useful in assessing the responses of high-elevation ecosystems to climate change and other anthropogenic drivers from a broad ecological perspective. Mountain research sites within the LTER (Long-Term Ecological Research) network are representative of various types of ecosystems and span a wide bioclimatic and elevational range. Here, we present a synthesis and a review of the main results from ecological studies in mountain ecosystems at 20 LTER sites in Italy, Switzerland and Austria covering in most cases more than two decades of observations. We analyzed a set of key climate parameters, such as temperature and snow cover duration, in relation to vascular plant species composition, plant traits, abundance patterns, pedoclimate, nutrient dynamics in soils and water, phenology and composition of freshwater biota. The overall results highlight the rapid response of mountain ecosystems to climate change, with site-specific characteristics and rates. As temperatures increased, vegetation cover in alpine and subalpine summits increased as well. Years with limited snow cover duration caused an increase in soil temperature and microbial biomass during the growing season. Effects on freshwater ecosystems were also observed, in terms of increases in solutes, decreases in nitrates and changes in plankton phenology and benthos communities. This work highlights the importance of comparing and integrating long-term ecological data collected in different ecosystems for a more comprehensive overview of the ecological effects of climate change. Nevertheless, there is a need for (i) adopting co-located monitoring site networks to improve our ability to obtain sound results from cross-site analysis, (ii) carrying out further studies, in particular short-term analyses with fine spatial and temporal resolutions to improve our understanding of responses to extreme events, and (iii) increasing comparability and standardizing protocols across networks to distinguish local patterns from global patterns.

Numerical Verification of an Analytical Model for Phase Noise in MEMS Oscillators

A new analytical formulation for phase noise in MEMS oscillators was recently presented encompassing the role of essential nonlinearities in the electrical and mechanical domains. In this paper, we validate the effectiveness of the proposed analytical formulation with respect to the unified theory developed by Demir et al. describing phase noise in oscillators. In particular, it is shown that, over a range of the second-order mechanical nonlinear stiffness of the MEMS resonator, both models exhibit an excellent match in the phase diffusion coefficient calculation for a square-wave MEMS oscillator.

Electron spectroscopy investigation of the oxidation of ultra-thin films of Ni and Cr on Fe(0 0 1)

We investigated the room temperature oxidation of ultra-thin Ni and Cr films grown on Fe(0 0 1). In particular, we characterized the degree of crystallinity and the stoichiometry of the oxide layers and addressed the chemical stability of the interface with the highly reactive Fe substrate by means of low-energy electron diffraction and x-ray and UV photoemission spectroscopy. In the Ni case we detected, upon oxidation, the formation of a Fe(3)O(4) layer covering the Ni oxide, due to the diffusion of Fe cations towards the surface. At high temperature and in ultra-high vacuum conditions, the Ni oxide dissolved and the Fe oxide layer was reduced to FeO. In the Cr case, we observed the formation of a thin Cr(2)O(3) oxide layer, showing a diffraction pattern compatible with a defective γ-Cr(2)O(3) phase. A thicker Cr oxide layer could be produced by oxidizing the sample at 300 °C, at the expense of the incorporation of trace amounts of Fe cations.

Enhanced atom mobility on the surface of a metastable film

A remarkable enhancement of atomic diffusion is highlighted by scanning tunneling microscopy performed on ultrathin metastable body-centered tetragonal Co films grown on Fe(001). The films follow a nearly perfect layer-by-layer growth mode with a saturation island density strongly dependent on the layer on which the nucleation occurs, indicating a lowering of the diffusion barrier. Density functional theory calculations reveal that this phenomenon is driven by the increasing capability of the film to accommodate large deformations as the thickness approaches the limit at which a structural transition occurs. These results disclose the possibility of tuning surface diffusion dynamics and controlling cluster nucleation and self-organization.

Direct observation of spin-resolved full and empty electron states in ferromagnetic surfaces

We present a versatile apparatus for the study of ferromagnetic surfaces, which combines spin-polarized photoemission and inverse photoemission spectroscopies. Samples can be grown by molecular beam epitaxy and analyzed in situ. Spin-resolved photoemission spectroscopy analysis is done with a hemispherical electron analyzer coupled to a 25 kV-Mott detector. Inverse photoemission spectroscopy experiments are performed with GaAs crystals as spin-polarized electron sources and a UV bandpass photon detector. As an example, measurements on the oxygen passivated Fe(100)-p(1×1)O surface are presented.

X-ray photoemission spectroscopy investigation of the interaction between 4-mercaptopyridine and the anatase TiO2 surface

In polymer-metal oxide hybrid solar cells, an extremely careful engineering of the interface is required to ensure good device performances. Recently, very promising results have been obtained by functionalizing titanium dioxide (TiO2) by means of 4-mercaptopyridine (4-MPy) molecules, showing the beneficial effect of these molecules on the interface morphology. This study investigates the nature of the interaction of 4-MPy molecules with the TiO2 surface by means of X-ray photoemission spectroscopy. In order to mimic the device processing conditions, our analysis is carried out on molecules adsorbed from solution on a nanocrystalline surface. According to our analysis, 4-MPy molecules (C5H5NS) are likely bound with the oxide through the nitrogen atom. The bonding precedes either via a covalent interaction with Lewis surface sites, or via hydrogen mediation, possibly in the form of hydrogen bonds. Interestingly, in the latter case, we also observe strong changes in the spectroscopic features attributed to the thiol group.

Severe Neonatal Metabolic Decompensation in Methylmalonic Acidemia Caused by CblD Defect

CblD disorder is an autosomal recessive, rare, heterogeneous disease with variable clinical presentations, depending on the nature and location of the MMADHC gene mutations. Mutations in MMADHC lead to three distinct phenotypes: cblD-MMA, cblD-HC, and cblD-MMA/HC. To date, 18 cblD patients have been reported. Six of them were affected by cblD-MMA, but only three had a known clinical history. One of these patients presented with a metabolic decompensation at 11 months; the second one, born prematurely, was diagnosed with cblD after being treated for intracranial hemorrhage, respiratory distress syndrome, necrotizing enterocolitis, and convulsions at birth; the third one was diagnosed at 5 years of age.Here we present a case of a cblD-MMA patient who had an acute neonatal onset with severe hyperammonemia requiring hemodiafiltration. To the best of our knowledge, this is the first cblD-MMA patient who presented acutely in the newborn period. He has developed well upon treatment with B12, carnitine, and hypoproteic diet. At present time, at the age of 7, he shows normal growth and cognitive development. Thus, it is likely that the aggressive treatment of this child with hemodiafiltration might have prevented him from long-term neurological sequelae. Overall, this case shows that even severe, neonatal-onset patients may display a vitamin B12-responsive MMA. Furthermore, it suggests that an early treatment with vitamins might be beneficial for patients presenting with neonatal-onset hyperammonemia regardless of the suspected disease and before receiving the biochemical diagnosis.

Diamond In-Line Monitors for Synchrotron Experiments

Diamond polycrystalline films have been synthesised using the Chemical Vapour Deposition (CVD) technique in order to fabricate new types of photo-detectors for the characterisation of x-ray light sources as encountered in synchrotron experiments. Since diamond exhibits a low absorption to low energy x-ray photons, these devices allow beam position monitoring with very little beam attenuation at photon energies as low as 2 keV. We present here diamond based new devices for four different applications, including (i) semitransparent beam intensity and (ii) position monitors with high position resolution (< 2 µm), (iii) beam profile monitors with 20 µm pitch resolution, and (iv) ultra-fast diamond detectors (response time < 100 ps) that enable the intensity and temporal monitoring of fast x-ray pulses. These devices can be used for in-line characterisation of synchrotron beam line experiments for permanent in-situ monitoring of beam instabilities during experiments as well as for synchrotron machine diagnostics.

Neutron Detectors Made From Chemically Vapour Deposited Semiconductors

In this paper, we present the results of investigations on the use of semiconductors deposited by chemical vapour deposition (CVD) for the fabrication of neutron detectors. For this purpose, 20 μm thick hydrogenated amorphous silicon (a-Si:H) pin diodes and 100 μm thick polycrystalline diamond resistive detectors were fabricated. The detectors were coupled to a neutron-charged particle converter : a layer of either gadolinium or boron (isotope 10 enriched) deposited by evaporation. We have demonstrated the capability of such neutron detectors to operate at neutron fluxes ranging from 101 to 106 neutrons/cm2.s. The fabrication of large area detectors for neutron counting or cartography through the use of multichannel reading circuits is discussed. The advantages of these detectors include the ability to produce large area detectors at low cost, radiation hardness (∼ 4 Mrad for a-Si:H and ∼ 100 Mrad for diamond), and for diamond, operation at temperatures up to 500°C. These properties enable the use of these devices for neutron detection in harsh environments. Thermal neutron detection efficiency up to 22 % and 3 % are expected by coupling a-Si:H diodes and diamond detectors to 3 μm thick gadolinium (isotope 157) and 2 μm thick boron layers, respectively.

Thalamic deep brain stimulation for treatment-refractory Tourette syndrome: two-year outcome

BACKGROUND

Eighteen patients with severe and refractory Tourette syndrome (TS) underwent bilateral thalamic deep brain stimulation (DBS).

OBJECTIVE

To assess the long-term outcome on tics, behavioral symptoms, and cognitive functions in the largest case series of thalamic DBS for TS to date.

METHODS

In this prospective cohort study, 15 of the original 18 patients were evaluated before and after surgery according to a standardized protocol that included both neuropsychiatric and neuropsychological assessments.

RESULTS

In addition to marked reduction in tic severity (p = 0.001), 24-month follow-up ratings showed improvement in obsessive-compulsive symptoms (p = 0.009), anxiety symptoms (p = 0.001), depressive symptoms (p = 0.001), and subjective perception of social functioning/quality of life (p = 0.002) in 15 of 18 patients. There were no substantial differences on measures of cognitive functions before and after DBS.

CONCLUSIONS

At 24-month follow-up, tic severity was improved in patients with intractable Tourette syndrome (TS) who underwent bilateral thalamic deep brain stimulation. Available data from 15 of 18 patients also showed that neuropsychiatric symptoms were improved and cognitive performances were not disadvantaged. Controlled studies on larger cohorts with blinded protocols are needed to verify that this procedure is effective and safe for selected patients with TS.

LEVEL OF EVIDENCE

This study provides class IV evidence that bilateral thalamic deep brain stimulation reduces global tic severity measured 24 months after implantation in patients with severe intractable Tourette syndrome.

Deep brain stimulation in 18 patients with severe Gilles de la Tourette syndrome refractory to treatment: the surgery and stimulation

BACKGROUND

There have been several reports of successful deep brain stimulation (DBS) for the treatment of severe Gilles de la Tourette syndrome (GTS).

METHOD

18 cases of GTS who were resistant to at least 6 months of standard and innovative treatments, as well as to psychobehavioural techniques, underwent DBS. DBS was placed bilaterally in the centromedian-parafascicular (CM-Pfc) and ventralis oralis complex of the thalamus. Patients were evaluated after surgery, with immediate and formal assessments at least every 3 months, including "on-off" and "sham off" in the first nine patients.

RESULTS

All patients responded well to DBS, although to differing degrees. The duration of follow-up assessments ranged from 3 to 18 months. The comorbid symptoms of obsessive-compulsive behaviour, obsessive-compulsive disorder, self-injurious behaviours, anxiety and premonitory sensations decreased after treatment with DBS. There were no serious permanent adverse effects.

CONCLUSIONS

DBS is a useful and safe treatment for severe GTS. The results of ours and previous DBS reports suggest that the CM-Pfc and ventralis oralis complex of the thalamus may be a good DBS target for GTS.

Interface coupling transition in a thin epitaxial antiferromagnetic film interacting with a ferromagnetic substrate

We report experimental evidence for a transition in the interface coupling between an antiferromagnetic film and a ferromagnetic substrate. The transition is observed in a thin epitaxial NiO film grown on top of Fe(001) as the film thickness is increased. Photoemission electron microscopy excited with linearly polarized x rays shows that the NiO film is antiferromagnetic at room temperature with in-plane uniaxial magnetic anisotropy. The anisotropy axis is perpendicular to the Fe substrate magnetization when the NiO thickness is less than about 15 A, but rapidly becomes parallel to the Fe magnetization for a NiO coverage higher than 25 A.

Long-term functional outcome measures in corticosteroid-treated complex regional pain syndrome

AIM

The aim of this paper was to assess the effects of low-dose systemic corticosteroid therapy in complex regional pain syndrome (CRPS), to measure the long-term functional outcome, and to evaluate an arbitrary scale of severity of CRPS.

METHODS

An evaluation of 31 consecutive subjects diagnosed with CRPS before and after they underwent corticosteroid therapy was carried out. The clinical and functional variables considered were evaluated at baseline, halfway through therapy, at the end and after 1, 6 and 12 months after the end of treatment. A clinical severity scale of CRPS was devised.

RESULTS

The comparison between baseline and post-treatment data of the principal variables resulted in all cases significant (P<0.001), as did, in most cases, the changes in variables between successive time intervals (P<0.05), supporting the long-term efficacy of treatment. The score of the clinical severity scale of CRPS showed a significant improvement in the one-year follow-up.

CONCLUSION

Corticosteroid therapy in CRPS provides a short-term response to the pain with a low risk of side effects. The improvement in all the variables considered persisted at one-year follow-up. The arbitrary scale of clinical severity of CRPS should be further tested in order to propose it as an instrument for use in following the course of CRPS.

Efficacy of low-dose intermittent subcutaneous interleukin (IL)--2 in antiviral drug--experienced human immunodeficiency virus--infected persons with detectable virus load: a controlled study of 3 il-2 regimens with antiviral drug therapy

To evaluate the safety and efficacy of 3 regimens of intermittent subcutaneous (sc) interleukin (IL)--2 in a phase 2 study, 61 antiviral drug-experienced human immunodeficiency virus (HIV)--positive patients were randomly assigned to one of the following study arms: antiretroviral therapy (ART) plus IL-2 (12 million IU [MIU] by continuous intravenous infusion, followed by 7.5 MIU twice a day, sc, every 8 weeks); ART plus IL-2 (7.5 MIU twice a day, sc, every 8 weeks); ART plus IL-2 (3 MIU twice a day, sc, every 4 weeks); or ART alone. A significant increase of circulating CD4 cells was observed in IL-2--treated subjects, compared with those given ART alone. Low doses of IL-2 were better tolerated. Despite the incomplete suppression of viral replication, IL-2 with ART did not increase either plasma viremia or cell-associated HIV DNA levels. Low doses of intermittent sc IL-2 induced a stable increase of peripheral CD4 cells that was indistinguishable from those associated with higher, less well-tolerated doses of IL-2.

Lack of interaction between flibanserin and antidepressants in inducing serotonergic syndrome in rats

This study was aimed at evaluating the ability of flibanserin, a 5-HT1A receptor full agonist with antidepressant potential, to induce the 5-HT syndrome (flat body posture, hindlimb abduction and forepaw treading) in rats previously administered with clinically active antidepressants imipramine, fluoxetine or paroxetine. The 5-HT syndrome was observed for 50 min after intraperitoneal administration of flibanserin (0, 8 or 64 mg/kg) given 10 min after antidepressants (0 or 15 mg/kg). Flibanserin induced flat body posture and very slight hindlimb abduction only at 64 mg/kg. No dose of flibanserin elicited forepaw treading. Similar but milder symptoms were induced by antidepressants. No interaction between flibanserin and antidepressants was observed. A dose of 10 mg/kg flibanserin did not change the flat body posture induced by 8 mg/kg (+/-)-8-OH-DPAT but antagonized (+/-)-8-OH-DPAT-induced forepaw treading.

Effects of cerestat and NBQX on functional and morphological outcomes in rat focal cerebral ischemia

This study investigated the ability of NBQX, an AMPA receptor antagonist, and cerestat, a NMDA receptor antagonist, to counteract neurological deficits and morphological damage induced by permanent occlusion of the left middle cerebral artery (MCAO model) in the rat. NBQX (3, 10, and 30 mg/kg, ip) injected at 10, 60, and 120 min postocclusion did not reduce the volume of infarct in the MCAO model of cerebral ischemia and had marginal effects on sensory dysfunctions (vibrissae stimulation and body proprioception) and no effects on motor dysfunctions (forelimb flexion and footfault test). Conversely, cerestat (0.3, 1, and 3 mg/kg, sc) injected at 10 and 120 min postocclusion significantly reduced the ischemic volume at the dose of 1 mg/kg, and, at the same dose, significantly attenuated behavioural deficits in the body proprioception and in the forelimb flexion tests.

Inhibition of R5X4 dualtropic HIV-1 primary isolates by single chemokine co-receptor ligands

The susceptibility of HIV-1 to chemokine-mediated inhibition may be lost as a consequence of the expanded usage of chemokine co-receptors frequently occurring in clade B isolates obtained from individuals with advanced disease. Since chemokine-based immune intervention is under intense investigation, it is crucial to determine its potential effect on primary dualtropic HIV isolates characterized by simultaneous utilization of CCR5 and CXCR4 chemokine co-receptors (R5X4 viruses). In the present study, the CCR5 binding chemokine regulated upon activation normal T cell expressed and secreted (RANTES) strongly inhibited the replication of two of eight primary R5X4 viruses in mitogen-activated primary peripheral blood mononuclear cells (PBMC). The CXCR4 antagonist AMD3100 efficiently suppressed the replication of other two HIV isolates, whereas the remaining four viruses were partially inhibited by treatment with either RANTES or AMD3100. The potency of chemokine-mediated inhibition was influenced by PBMC donor variability, but it was usually independent from the levels of expression of CCR5 or CXCR4. Dual co-receptor usage was maintained by the viruses after two serial passages on U87.CD4 astrocytic cell lines expressing exclusively either CCR5 or CXCR4. The gp120 env variable domains were sequenced before and after passages on U87.CD4 cells. Virus replication into U87.CD4-CXCR4 cells did not result in changes in the V3 region but perturbed the dominant env V4 sequence. Interestingly, double passage onto U87.CD4-CXCR4 cells determined the loss of susceptibility to RANTES inhibition. In conclusion, interference with CCR5 may efficiently inhibit the replication of at least some dualtropic HIV-1 strains, whereas forced CXCR4 usage may result in viral escape from CCR5-dependent inhibitory effects.

An improved in vivo rat model for the study of mechanical ventilatory support effects on organs distal to the lung

OBJECTIVE

To study the influence of different mechanical ventilatory support strategies on organs distal to the lung, we developed an in vivo rat model, in which the effects of different tidal volume values can be studied while maintaining other indexes.

DESIGN

Prospective, randomized animal laboratory investigation.

SETTING

University laboratory of Ospedale Maggiore di Milano-Instituto di Ricovero e Cura a Carattere Scientifico.

SUBJECTS

Anesthetized, paralyzed, and mechanically ventilated male Sprague-Dawley rats.

INTERVENTIONS

Two groups of seven rats each were randomized to receive tidal volumes of either 25% or 75% of inspiratory capacity (IC), calculated from a preliminary estimation of total lung capacity. Ventilation strategies for the two groups were as follows: a) 25% IC, 9.9+/-0.8 mL/kg; frequency, 59+/-4 beats/min; positive end-expiratory pressure, 3.6+/-0.8 cm H2O; and peak inspiratory airway pressure (Paw), 13.2+/-2 cm H20; and b) 75% IC, 29.8+/-2.9; frequency, 23+/-13; positive end-expiratory pressure, 0; peak inspiratory Paw, 29.0+/-3.

MEASUREMENTS AND MAIN RESULTS

Mean arterial pressure (invasively monitored) remained well above adequate perfusion pressure values throughout, and no significant difference was seen between the two groups. PaO2, pHa, and PaCO2 values were compared after 60 mins of ventilation and again, no significant difference was seen between the two groups (PaO2, 269+/-25 and 260+/-55 torr; pHa, 7.432+/-0.09 and 7.415+/-0.03; PaCO2, 35.4+/-8 and 32.5+/-2 torr, for the 25% IC and 75% IC groups, respectively). Mean Paws were not different (6.4+/-0.8 cm H2O in the 25% IC groups, and 6.1+/-1.2 in the 75% IC groups, respectively). At the end of the experiment, animals were killed and the liver and kidney isolated, fixed in 4% formalin, cut, and stained for optic microscopy. Kidneys from rats ventilated with 75% IC showed increased Bowman's space with collapse of the glomerular capillaries. This occurred in a greater percentage of rats ventilated with 75% IC (0.67+/-0.2 vs. 0.29+/-0.2, 75% IC vs. 25% IC, respectively; p < .05). Perivascular edema was also present in rats ventilated with 75% IC (p < .05). Morphometric determinations of the empty zones (index of edema) demonstrated a trend toward differences between 75% IC livers and 25% IC (0.14+/-0.05 vs. 0.11+/-0.02, respectively).

CONCLUSION

We conclude that it is possible to study the effects of mechanical ventilatory support on organs distal to the lung by means of an in vivo rat model.

Shorter survival of SDF1-3'A/3'A homozygotes linked to CD4+ T cell decrease in advanced human immunodeficiency virus type 1 infection

The SDF-1 3'A allelic polymorphism has been reported to influence either positively or negatively the progression of human immunodeficiency virus type 1 (HIV-1) disease. Therefore, the SDF-1 genotype of 729 HIV-1-infected individuals pooled from 3 distinct cohorts was determined. A statistically nonsignificant association between the SDF1-3'A/3'A genotype and accelerated disease progression was evident among seroconverters (n=319), but a striking correlation of decreased survival after either diagnosis of AIDS according to the 1993 definition or loss of CD4(+) T cell counts <200 was observed. The relative hazards for SDF1-3'A/3'A homozygotes, compared with heterozygotes and wild-type homozygotes were 2.16 (P=.0047), for time from diagnosis according to the 1993 Centers for Disease Control and Prevention AIDS case definition (AIDS-'93) to death, and 3.43 (P=.0001), for time from CD4(+) T cells <200 to death. Because no difference in survival was observed after diagnosis according to AIDS-'87, the association of the SDF1-3'A/3'A genotype with the accelerated progression of late-stage HIV-1 disease appears to be explained for the most part by the loss of CD4(+) T lymphocytes.

Immunologic reconstitution by interleukin-2: facts and open questions

Interleukin-2 (IL-2), one of the most potent immunoregulatory and inflammatory cytokines, is being tested in phase III clinical trials in order to demonstrate its efficacy in combination with current antiviral agents in preventing the occurrence of opportunistic infections and death in individuals infected by the human immunodeficiency virus (HIV). In the meantime, its capacity to boost the number of CD4+ T cells in peripheral blood has been confirmed by a number of individual phase I/II trials conducted in different countries by independent investigators. In the face of this remarkable result, little is known of the effects exerted by this cytokine once administered to infected individuals in terms of its impact on different immunologic functions. The recent acquisitions on the important role played by latently infected cells in in vivo infection in reinitiating HIV replication and cytopathicity once antiviral therapy is suspended or becomes suboptimal, has shed new light on the possibility of utilizing immunologic strategies, including IL-2, for eradicating the virus from latent reservoirs. Results from a clinical trial conducted at our Institute indicate a decrease in lymphocyte-associated HIV DNA after IL-2 administration, supporting this hypothesis.

Effect of flibanserin (BIMT 17), fluoxetine, 8-OH-DPAT and buspirone on serotonin synthesis in rat brain

In male rats, the effects of the administration of the novel serotonergic agent flibanserin on the synthesis of 5-HT were evaluated in the frontal cortex (FC), hippocampus (Hip) and brainstem (Br). The selective serotonergic uptake blocker, fluoxetine, and two serotonin1A (5-HT1A) agonists, 8-hydroxy-2-(di-n-propylamino)tetraline (8-OH-DPAT) and buspirone, were used as reference compounds. The synthesis of 5-HT was assessed by measuring the accumulation of 5-hydroxytryptophan (5-HTP) after blockade of aromatic amino acid decarboxylase induced by m-hydroxybenzylhydrazine (NSD-1015), at 100 mg/kg i.p., 30 min before sacrifice. Flibanserin, 8-OH-DPAT and buspirone were given 15 min before NSD-1015, while fluoxetine 120 min before NSD-1015. In our experimental conditions, a different efficacy, expressed as percentage of maximal inhibition (Max) of 5-HTP accumulation, and a different potency, expressed in terms of minimal effective dose (MED), were observed in different brain areas with tested compounds. Flibanserin (1-32 mg/kg) decreased 5-HT synthesis with preferential activity in the FC, compared to the Hip and Br, both in terms of potency (MED=2 mg/kg in FC, 16 mg/kg in Hip and Br) and efficacy (Max=65% in FC, 44% in Hip and 29% in Br). Fluoxetine (1-30 mg/kg) decreased 5-HT synthesis with preferential activity in FC than in Hip and Br, only in terms of potency (MED=3 mg/kg in FC, 10 mg/kg in Hip and Br), this result being similar to that observed for flibanserin. In contrast, it showed greater efficacy both in FC and Hip (Max about 60%), than in Br (Max=49%). On the contrary, 8-OH-DPAT (0.3-3 mg/kg) decreased 5-HT synthesis with the same potency in all brain regions (MED=3 mg/kg) and showed the greatest efficacy in FC than in Hip and Br (Max=56% in FC, 49% in Hip and 40% in Br). Furthermore, buspirone (3-30 mg/kg), while inhibiting 5-HTP accumulation in all areas with the same efficacy (Max about 30%), seemed to have higher potency in Br than in FC and Hip (MED=3 mg/kg in Br, 10 mg/kg in FC and Hip). The results in terms of regional differences are discussed.

Envelope-dependent restriction of human immunodeficiency virus type 1 spreading in CD4(+) T lymphocytes: R5 but not X4 viruses replicate in the absence of T-cell receptor restimulation

The human immunodeficiency virus (HIV) replicates in activated CD4(+) T lymphocytes. However, only CD4(+) Th2 and Th0, but not Th1, CD4(+) T-cell clones have been reported to efficiently support HIV-1 replication. This dichotomous pattern was further investigated in the present study in Th1, Th2, or Th0 cell lines derived from umbilical human cord blood and in T-cell clones obtained from the peripheral blood mononuclear cells (PBMC) of healthy adults. Both primary and laboratory-adapted HIV-1 strains with CCR5 as the exclusive entry coreceptor (R5 viruses) efficiently replicated in Th1, Th2, and Th0 cells. In sharp contrast, CXCR4-dependent (X4) viruses poorly replicated in both polarized and unpolarized CD4(+) T cells, including adults' PBMC infected several days after mitogenic stimulation. Unlike the X4 HIV-1(NL4-3), a chimera in which the env gene had been replaced with that of the R5 HIV-1(NL(AD8)), efficiently replicated in both Th1 and Th2 cells. This X4-dependent restriction of HIV replication was not explained by either the absence of functional CXCR4 on the cell surface or by the inefficient viral entry and reverse transcription. T-cell receptor stimulation by anti-CD3 monoclonal antibodies fully rescued X4 HIV-1 replication in both Th1 and Th2 cells, whereas it did not alter the extent and kinetics of R5 HIV-1 spreading. Thus, R5 HIVs show a replicative advantage in comparison to X4 viruses in their ability to efficiently propagate among suboptimally activated T lymphocytes, regardless of their polarized or unpolarized functional profiles. This observation may help to explain the absolute predominance of R5 HIVs over X4 viruses observed after viral transmission and during early-stage disease.

Behavioral effects of flibanserin (BIMT 17)

Flibanserin is a 5-HT1A agonist that, in contrast to other 5-HT1A receptor agonists, is capable of activating 5-HT1A receptors in frontal cortex. Flibanserin also behaves as an antagonist at 5-HT2A receptors. This compound has been described to be a putative fast-acting antidepressant owing to these properties. In the present study, the effect of flibanserin was investigated in several behavioral paradigms different from animal models of depression. Intraperitoneal flibanserin, at doses of 4-8 mg/kg, antagonized d-amphetamine- and (+)SKF-10047- induced hypermotility in mice and rats. At doses of 816 mg/kg, flibanserin exerted anxiolytic-like effects in the light/dark exploratory test and stress-induced hyperthermia in mice, and antagonized d-amphetamine- and apomorphine-induced stereotypy in rats. At the dose of 16 mg/kg, flibanserin reduced spontaneous motor activity in rats. At the dose of 32 mg/kg, flibanserin did not exert any clear effect on spontaneous motor activity in mice, or on the elevated plus-maze and the water maze in rats.

Effect of antipsychotic drugs and selective dopaminergic antagonists on dopamine-induced facilitatory activity in prelimbic cortical pyramidal neurons. An in vitro study

Intracellular recordings were obtained from 119 pyramidal neurons localized in prelimbic cortex, five in the dorsal cingulate cortex, one in the infralimbic cortex, one in the border of prelimbic and cingulate cortex and two in the border of prelimbic and infralimbic cortex. The passive membrane properties of these pyramidal neurons (i.e. resting membrane potential, input membrane resistance, shape of the tetrodotoxin-sensitive action potentials, spike frequency adaptation with a prominent postspike afterhyperpolarization, tetrodotoxin-sensitive inward rectification in the depolarizing direction and the absence of bursting) suggested that they resembled regular spiking or intrinsically bursting pyramidal neurons. Bath application of dopamine (EC50 of 1.8 microM) produced a reversible facilitatory effect on all 119 pyramidal neurons localized in the middle layer of the prelimbic cortex. No consistent change in membrane potential was detected during the application of dopamine. No effect of dopamine was noted on the nine pyramidal neurons that were not localized in the prelimbic cortex. The facilitatory effect of dopamine in prelimbic cortex was concentration dependently antagonized by haloperidol, risperidone, quetiapine, clozapine and by the selective D4 dopaminergic receptor antagonist L-745,870, but not by the selective D2/D3 dopaminergic receptor antagonist (-)-sulpiride. (+)-SCH 23390, which is a selective D1/D5 dopamine receptor antagonist, produced, similarly to dopamine, a facilitatory effect per se, and an additive effect when co-administered with dopamine. These results provide evidence that dopamine has a facilitatory effect specifically on pyramidal neurons localized in the middle layer of prelimbic cortex. Antipsychotic drugs and L-745,870 block this effect of dopamine.

Defective nef alleles in a cohort of hemophiliacs with progressing and nonprogressing HIV-1 infection

Deletion of the nef gene results in viral attenuation and confers protection against challenge with wild-type simian immunodeficiency virus in macaques. Regarding HIV-1 infection, a few long-term nonprogressors (LTNP) with nef deletions have been described. In this study, the nef genes of a group of seven LTNP and eight progressors, all belonging to the same cohort of infected hemophiliacs, were analyzed by cloning and sequencing from both virion RNA and peripheral blood mononuclear cell-associated proviral DNA. Defective nef sequences coexisted with full-length nef open reading frames in five of seven LTNP and two of eight progressors. The proportion of disrupted nef sequences within each individual was significantly higher in LTNP (ranging from 10 to 63%) than in progressors (ranging from 9 to 21%) (P = 0.013). Moreover, in-frame small deletions predicting to encode Nef were found in all RNA- and DNA-derived clones from one LTNP and four progressors. A chimeric virus in which the nef gene of NL4.3 was substituted with the nef allele containing the deletion of two alanines at position 49-50 found in two progressors showed a defective replicative capacity compared to NL4.3 virus. In summary, hemophiliacs with either progressing or nonprogressing HIV-1 infection are characterized by the presence of defective nef variants.

Human CD34(+) cells express CXCR4 and its ligand stromal cell-derived factor-1. Implications for infection by T-cell tropic human immunodeficiency virus

Human CD34(+) hematopoietic progenitor cells obtained from bone marrow (BM), umbilical cord blood (UCB), and mobilized peripheral blood (MPB) were purified and investigated for the expression of the chemokine receptor CXCR4 and its ligand, stromal cell-derived factor-1 (SDF-1). CXCR4 was found present on the cell surface of all CD34(+) cells, although it was expressed at lower density on MPB with respect to BM CD34(+) cells. Freshly isolated and in vitro-cultured CD34(+) cells also coexpressed SDF-1 mRNA, as determined by reverse transcriptase-polymerase chain reaction (RT-PCR). Of interest, CD34(+)/CD38(+) committed progenitor cells, unlike primitive CD34(+)/CD38(-) cells, expressed SDF-1 mRNA. Supernatants from in vitro-cultured CD34(+) cells contained substantial (3 to 8 ng/mL) amounts of SDF-1 by enzyme-linked immunosorbent assay and induced migration of CD34(+) cells. Because CD34(+) cells express low levels of CD4, the primary receptor of the human immunodeficiency virus (HIV), and CXCR4 is a coreceptor for T-cell tropic (X4) HIV strains, we investigated the susceptibility of CD34(+) cells to infection by this subset of viruses. Lack of productive infection was almost invariably observed as determined by a conventional RT activity in culture supernatants and by real-time PCR for HIV DNA in CD34(+) cells exposed to both laboratory adapted (LAI) and primary (BON) X4 T-cell tropic HIV-1 strain. Soluble gp120 Env (sgp120) from X4 HIV-1 efficiently blocked binding of the anti-CD4 Leu3a monoclonal antibody (MoAb) to either human CD4(+) T cells or CD34(+) cells. In contrast, sgp120 interfered with an anti-CXCR4 MoAb binding to human T lymphocytes, but not to CD34(+) cells. However, CXCR4 on CD34(+) cells was downregulated by SDF-1. These results suggest that CXCR4 and its ligand SDF-1 expressed in CD34(+) progenitors may play an important role in regulating the local and systemic trafficking of these cells. Moreover, these findings suggest multiple and potentially synergistic mechanisms at the basis of the resistance of CD34(+) cells to X4 HIV infection, including their ability to produce SDF-1, and the lack of CXCR4 internalization following gp120 binding to CD4.

BIIR 561 CL: a novel combined antagonist of alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors and voltage-dependent sodium channels with anticonvulsive and neuroprotective properties

Antagonists of glutamate receptors of the alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) subtype, as well as of voltage-gated sodium channels, exhibit anticonvulsive and neuroprotective properties in vivo. One can postulate that a compound that combines both principles might be useful for the treatment of disorders of the central nervous system, like focal or global ischemia. Here, we present data on the effects of dimethyl-(2-[2-(3-phenyl-[1,2, 4]oxadiazol-5-yl)-phenoxy]ethyl)-amine hydrochloride (BIIR 561 CL) on neuronal AMPA receptors and voltage-dependent sodium channels. BIIR 561 CL inhibited AMPA receptor-mediated membrane currents in cultured cortical neurons with an IC50 value of 8.5 microM. The inhibition was noncompetitive. In a cortical wedge preparation, BIIR 561 CL reduced AMPA-induced depolarizations with an IC50 value of 10.8 microM. In addition to the effects on the glutamatergic system, BIIR 561 CL inhibited binding of radiolabeled batrachotoxin to rat brain synaptosomal membranes with a Ki value of 1.2 microM. The compound reduced sodium currents in voltage-clamped cortical neurons with an IC50 value of 5.2 microM and inhibited the veratridine-induced release of glutamate from rat brain slices with an IC50 value of 2.3 microM. Thus, BIIR 561 CL inhibited AMPA receptors and voltage-gated sodium channels in a variety of preparations. BIIR 561 CL suppressed tonic seizures in a maximum electroshock model in mice with an ED50 value of 2.8 mg/kg after s.c. administration. In a model of focal ischemia in mice, i.p. administration of 6 or 60 mg/kg BIIR 561 CL reduced the area of the infarcted cortical surface. These data show that BIIR 561 CL is a combined antagonist of AMPA receptors and voltage-gated sodium channels with promising anticonvulsive and neuroprotective properties.