Biomimetic behaviors in hydrogel artificial cells through embedded organelles

Artificial cells are biomimetic structures formed from molecular building blocks that replicate biological processes, behaviors, and architectures. Of these building blocks, hydrogels have emerged as ideal, yet underutilized candidates to provide a gel-like chassis in which to incorporate both biological and nonbiological componentry which enables the replication of cellular functionality. Here, we demonstrate a microfluidic strategy to assemble biocompatible cell-sized hydrogel-based artificial cells with a variety of different embedded functional subcompartments, which act as engineered synthetic organelles. The organelles enable the recreation of increasingly biomimetic behaviors, including stimulus-induced motility, content release through activation of membrane-associated proteins, and enzymatic communication with surrounding bioinspired compartments. In this way, we showcase a foundational strategy for the bottom-up construction of hydrogel-based artificial cell microsystems which replicate fundamental cellular behaviors, paving the way for the construction of next-generation biotechnological devices.

A microfluidic platform for the controlled synthesis of architecturally complex liquid crystalline nanoparticles

Soft-matter nanoparticles are of great interest for their applications in biotechnology, therapeutic delivery, and in vivo imaging. Underpinning this is their biocompatibility, potential for selective targeting, attractive pharmacokinetic properties, and amenability to downstream functionalisation. Morphological diversity inherent to soft-matter particles can give rise to enhanced functionality. However, this diversity remains untapped in clinical and industrial settings, and only the simplest of particle architectures [spherical lipid vesicles and lipid/polymer nanoparticles (LNPs)] have been routinely exploited. This is partially due to a lack of appropriate methods for their synthesis. To address this, we have designed a scalable microfluidic hydrodynamic focusing (MHF) technology for the controllable, rapid, and continuous production of lyotropic liquid crystalline (LLC) nanoparticles (both cubosomes and hexosomes), colloidal dispersions of higher-order lipid assemblies with intricate internal structures of 3-D and 2-D symmetry. These particles have been proposed as the next generation of soft-matter nano-carriers, with unique fusogenic and physical properties. Crucially, unlike alternative approaches, our microfluidic method gives control over LLC size, a feature we go on to exploit in a fusogenic study with model cell membranes, where a dependency of fusion on particle diameter is evident. We believe our platform has the potential to serve as a tool for future studies involving non-lamellar soft nanoparticles, and anticipate it allowing for the rapid prototyping of LLC particles of diverse functionality, paving the way toward their eventual wide uptake at an industrial level.

A Multiscale Study of Phosphorylcholine Driven Cellular Phenotypic Targeting

Phenotypic targeting requires the ability of the drug delivery system to discriminate over cell populations expressing a particular receptor combination. Such selectivity control can be achieved using multiplexed-multivalent carriers often decorated with multiple ligands. Here, we demonstrate that the promiscuity of a single ligand can be leveraged to create multiplexed-multivalent carriers achieving phenotypic targeting. We show how the cellular uptake of poly(2-(methacryloyloxy)ethyl phosphorylcholine)-poly(2-(diisopropylamino)ethyl methacry-late) (PMPC-PDPA) polymersomes varies depending on the receptor expression among different cells. We investigate the PMPC-PDPA polymersome insertion at the single chain/receptor level using all-atom molecular modeling. We propose a theoretical statistical mechanics-based model for polymersome-cell association that explicitly considers the interaction of the polymersome with the cell glycocalyx shedding light on its effect on the polymersome binding. We validate our model experimentally and show that the binding energy is a nonlinear function, allowing us to tune the interaction by varying the radius and degree of polymerization. Finally, we show that PMPC-PDPA polymersomes can be used to target monocytes in vivo due to their promiscuous interaction with SRB1, CD36, and CD81.

Manufacturing polymeric porous capsules

Polymeric porous capsules represent hugely promising systems that allow a size-selective through-shell material exchange with their surroundings. They have vast potential in applications ranging from drug delivery and chemical microreactors to artificial cell science and synthetic biology. Due to their porous core-shell structure, polymeric porous capsules possess an enhanced permeability that enables the exchange of small molecules while retaining larger compounds and macromolecules. The cross-capsule transfer of material is regulated by their pore size cut-off, which depends on the molecular composition and adopted fabrication method. This review outlines the main strategies for manufacturing polymeric porous capsules and provides some practical guidance for designing polymeric capsules with controlled pore size.

Thymosin β4 and β10 are highly expressed at the deep infiltrative margins of colorectal cancer - A mass spectrometry analysis

OBJECTIVE

Colorectal cancer (CRC) is a complicated tumor, involving several oncogenic signaling pathways, and with a molecular mechanism not fully understood yet. The implication of thymosin β4 (Tβ4) with tumor insurgence and in migration of CRC cells was evidenced in the past with different methodologies, while Tβ10 connection with CRC has been sporadically investigated. This study focused on the implication of both types of thymosin in CRC progression and invasion by analyzing the changes in their levels according to different zones of the tumor, and to Dukes stage and budding index.

PATIENTS AND METHODS

Tβ4 and Tβ10 were analyzed in deep and superficial tumor samples, and normal mucosa from 18 patients. Concentrations of Tβ4 and Tβ10 have been measured by high-pressure liquid chromatography (HPLC) coupled to electrospray-ion trap mass spectrometry (ESI-IT-MS). MS data were compared by t-test and ANOVA statistical analysis. Identification of thymosin and their proteoforms has been performed by HPLC-high resolution-ESI-IT-MSMS.

RESULTS

Both Tβ4 and Tβ10, exhibited intra-tumoral quantitative differences, being upregulated in the deep part of the CRC. They exhibited, moreover, strong association with the Dukes stage and the budding grade, being more concentrated in patients at Dukes stage B and with budding index "2".

CONCLUSIONS

The results obtained in the present investigation encouraged the hypothesis that the two thymosin are involved in colorectal cancer progression, and in promoting cancer invasion. Thus, they are good candidates to be diagnostic/prognostic biomarkers and therapy targets.

Prediction of Chronic Inflammation for Inhaled Particles: the Impact of Material Cycling and Quarantining in the Lung Epithelium

On a daily basis, people are exposed to a multitude of health-hazardous airborne particulate matter with notable deposition in the fragile alveolar region of the lungs. Hence, there is a great need for identification and prediction of material-associated diseases, currently hindered due to the lack of in-depth understanding of causal relationships, in particular between acute exposures and chronic symptoms. By applying advanced microscopies and omics to in vitro and in vivo systems, together with in silico molecular modeling, it is determined herein that the long-lasting response to a single exposure can originate from the interplay between the newly discovered nanomaterial quarantining and nanomaterial cycling between different lung cell types. This new insight finally allows prediction of the spectrum of lung inflammation associated with materials of interest using only in vitro measurements and in silico modeling, potentially relating outcomes to material properties for a large number of materials, and thus boosting safe-by-design-based material development. Because of its profound implications for animal-free predictive toxicology, this work paves the way to a more efficient and hazard-free introduction of numerous new advanced materials into our lives.

Size dependency of gold nanoparticles interacting with model membranes

The rapid development of nanotechnology has led to an increase in the number and variety of engineered nanomaterials in the environment. Gold nanoparticles (AuNPs) are an example of a commonly studied nanomaterial whose highly tailorable properties have generated significant interest through a wide range of research fields. In the present work, we characterise the AuNP-lipid membrane interaction by coupling qualitative data with quantitative measurements of the enthalpy change of interaction. We investigate the interactions between citrate-stabilised AuNPs ranging from 5 to 60 nm in diameter and large unilamellar vesicles acting as a model membrane system. Our results reveal the existence of two critical AuNP diameters which determine their fate when in contact with a lipid membrane. The results provide new insights into the size dependent interaction between AuNPs and lipid bilayers which is of direct relevance to nanotoxicology and to the design of NP vectors.

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

STUDY QUESTION

Are JC polyomavirus (JCPyV) and BK polyomavirus (BKPyV) infections associated with spontaneous abortion (SA)?

SUMMARY ANSWER

There is no association of JCPyV or BKPyV with SA.

WHAT IS KNOWN ALREADY

A large number of risk factors have been associated with SA. The role of polyomaviruses, including JCPyV and BKPyV, in SA remains to be clarified.

STUDY DESIGN, SIZE, DURATION

This is a case-control study including women affected by spontaneous abortion (SA, n = 100, the cases) and women who underwent voluntary interruption of pregnancy (VI, n = 100, the controls).

PARTICIPANTS/MATERIALS, SETTING, METHODS

Viral DNAs were investigated by qualitative PCR and quantitative droplet-digital PCR (ddPCR) in matched chorionic villi tissues and peripheral blood mononuclear cells (PBMCs) from SA (n = 100) and VI (n = 100). Indirect ELISAs with mimotopes/synthetic peptides corresponding to JCPyV and BKPyV viral capsid protein 1 epitopes were then employed to investigate specific IgG antibodies against JCPyV and BKPyV in human sera from SA (n = 80) and VI (n = 80) cohorts.

MAIN RESULTS AND THE ROLE OF CHANCE

JCPyV DNA was detected in 51% and 61% of SA and VI samples, respectively, with a mean viral DNA load of 7.92 copy/104 cells in SA and 5.91 copy/104 cells in VI (P > 0.05); BKPyV DNA was detected in 11% and 12% of SA and VI specimens, respectively, with a mean viral DNA load of 2.7 copy/104 cells in SA and 3.08 copy/104 cells in VI (P > 0.05). JCPyV was more prevalent than BKPyV in both SA and VI specimens (P < 0.0001). In PBMCs from the SA and VI cohorts, JCPyV DNA was detected with a prevalence of 8% and 12%, respectively, with a mean viral DNA load of 2.29 copy/104 cells in SA and 1.88 copy/104 cells in VI (P > 0.05). The overall prevalence of serum IgG antibodies against JCPyV detected by indirect ELISAs was 52.5% and 48.7% in SA and VI groups, respectively, whereas BKPyV-positive sera were found in 80% SA and 78.7% VI samples.

LIMITATIONS, REASONS FOR CAUTION

This study did not investigate the presence of viral mRNA and/or proteins, which are indicative of an active viral infection, and these might be taken into consideration in future studies.

WIDER IMPLICATIONS OF THE FINDINGS

JCPyV and BKPyV DNA sequences were detected and quantitatively analyzed for the first time by PCR/ddPCR in chorionic villi tissues and PBMCs from SA and VI specimens. Moreover specific immunological approaches detected serum IgG against JCPyV/BKPyV. Statistical analyses, however, do not indicate an association between these polyomaviruses and SA.

STUDY FUNDING/COMPETING INTEREST(S)

This work was supported by the University of Ferrara, FAR research grants and the University Hospital of Ferrara/University of Ferrara joint grant. No potential conflicts of interest were disclosed.

Rates of antibiotic resistance/sensitivity in bacterial cultures of hidradenitis suppurativa patients

BACKGROUND

Antibiotic (AB) treatment is one of the first steps in the management of hidradenitis suppurativa (HS). Bacteria, in HS patients, may play a double role, as triggering factors of inflammatory reactions and/or agents of infection.

OBJECTIVES

The aims of this study are as follows: (i) to assess prevalence and AB resistance of bacterial growths in HS patients (ii) assessment of the clinical relevance of obtained data in guiding the selection of the most effective AB therapy.

METHODS

Purulent material from 137 skin lesions of HS patients was collected with swabs. Bacterial flora and AB sensitivity were determined using microbiological cultures for aerobic and anaerobic bacteria.

RESULTS

A total of 114 samples resulted positive for bacteria. Sample was collected from the axillae, groin and perianal areas. A total of 163 single bacterial growths were observed; 55% were Gram-positive and 44% were Gram-negative. Among them, 18.4% were anaerobic. The most frequent bacterial families included enterobacteriaceae (30.7%), Staphylococcus (25.2%) and Streptococcus (14.1%). The most frequent genus or species were proteus spp. (13.5%) and Escherichia coli (9.8%). The prevalence of AB resistance observed was clindamycin 65.7%, rifampicin 69.3%, penicillin 70.0%, ciprofloxacin 74%, tetracycline 84.7% and erythromycin 89.0%. A limitation of the study is represented the short culture period adopted which may have impaired the isolation of anaerobes.

CONCLUSIONS

Bacterial growth in HS patients has shown a high level of resistance to ABs, including rifampicin, clindamycin and tetracyclines, cited as an empiric choice in HS therapeutic guidelines. A targeted and specific AB therapy, driven by microbiological evaluations with prolonged culture periods, seems more appropriate than empiric, generic, non-specific, therapeutic approaches. Current knowledge regarding HS bacterial AB resistance should be considered in the update of current therapeutic guidelines for HS.

Bottom-Up Evolution of Vesicles from Disks to High-Genus Polymersomes

Polymersomes are vesicles formed by the self-assembly of amphiphilic copolymers in water. They represent one of the most promising alternatives of natural vesicles as they add new possibilities in the amphiphiles' molecular engineering of aqueous compartments. Here we report the design of polymersomes using a bottom-up approach wherein self-assembly of amphiphilic copolymers poly(2-(methacryloyloxy) ethyl phosphorylcholine)-poly(2-(diisopropylamino) ethyl methacrylate) (PMPC-PDPA) into membranes is tuned using pH and temperature. We report evolution from disk micelles, to vesicles, to high-genus vesicles (vesicles with many holes), where each passage is controlled by pH switch or temperature. We show that the process can be rationalized, adapting membrane physics theories to disclose scaling principles that allow the estimation of minimal radius of vesiculation as well as chain entanglement and coupling. This approach allows us to generate nanoscale vesicles with genus from 0 to 70, which have been very elusive and difficult to control so far.

Treatment of very preterm preeclampsia via heparin-mediated extracorporeal LDL-precipitation (H.E.L.P.) apheresis: The Freiburg preeclampsia H.E.L.P.-Apheresis study

OBJECTIVE

Soluble Fms-like tyrosine kinase-1 (sFlt-1) is thought to be causative in the pathogenesis of preeclampsia (PE) and specific removal of sFlt-1 via dextran sulfate cellulose (DSC)-apheresis was suggested as cure to allow prolongation of pregnancy in preterm PE. However, in addition a deranged lipoprotein metabolism may impact endothelial and placental function in PE. Lipoprotein-apheresis by heparin-mediated extracorporeal LDL-precipitation (H.E.L.P.) was previously applied and has been shown to alleviate symptoms in PE. This clinical trial reevaluates the clinical efficacy of H.E.L.P.-apheresis in PE considering sFlt-1.

STUDY DESIGN

Open pilot study assessing the prolongation by H.E.L.P.-apheresis in 6 women (30-41 years) with very preterm PE (24+4 to 27+0 gestational weeks (GW)) (NCT01967355) compared to a historic control-group matched for GW at admission (<28 GW; n = 6). Clinical outcome of mothers and babies, and pre- and post H.E.L.P.-apheresis levels of sFlt-1 and PlGF were monitored.

MAIN OUTCOME MEASURES

In apheresis patients (2-6 treatments), average time from admission to birth was 15.0 days (6.3 days in controls; p = 0.027). Lung maturation was induced in all treated cases, and all children were released in healthy condition. Apheresis reduced triglycerides and LDL-cholesterol by more than 40%. Although H.E.L.P.-apheresis induced a transient peak baseline levels did not change and rather stabilized sFlt-1 levels at pre-apheresis levels throughout treatments, with sFlt-1/PLGF ratio remaining unaffected.

CONCLUSIONS

H.E.L.P.-apheresis proved again to be safe and prolongs pregnancies in PE. However, without changing sFlt-1 levels below baseline lowering lipids or other yet undefined factors appear to be of more relevance than reducing sFlt-1.

Method for the Study of Regional Myocardial Perfusion in Patients with Atherosclerotic Coronary Artery Disease

In patients with ischemic heart disease the evaluation of regional myocardial perfusion by 133Xenon intra-coronary injection using a gamma camera computer system allows the detection of regional alterations of myocardial perfusion. While at rest a minority of the patients studied shows large alterations, during pacing induced angina a severe reduction of regional myocardial perfusion can be evidenced both in initial distribution scintigrams, when the injection is performed during angina, and on the washout curves when angina is induced immediately after the injection, during the course of the washout.

Diagnosis of a neonatal ophthalmic discharge, Ophthalmia neonatorum, in the molecular age: investigation for a correct therapy

An early double case of acute Ophthalmia neonatorum in 3-day-old twins is reported. Culture of eye swabs showed a wide bacterial polymorphism, in which common bacteria, such as Klebsiella pneumoniae, Streptococcus pneumoniae, Corynebacterium ulcerans and other Enterobacteriaceae, coexisted with atypical Mycoplasmataceae and Chlamydiaceae from resident cervical-vaginal maternal microbiota. The neonates were in an apparently healthy state, but showed red eyes with abundant greenish-yellow secretion, mild chemosis and lid edema. The maternal cervical-vaginal ecosystem resulted differently positive to the same common cultivable, atypical bacteria culturally and molecularly determined. This suggested a direct maternal-foetal transmission or a further foetal contamination before birth. An extended culture analysis for common bacteria to atypical ones was decisive to describe the involvement of Mycoplasmas (M. hominis and U. urealyticum) within the scenario of the Ophthalmia neonatorum in a Caucasian couple. The introduction of a routine PCR molecular analysis for Chlamydiaceae and N. gonorrhoeae allowed to establish which of these were present at birth, and contributed to determine the correct laboratory diagnosis and to define an adequate therapeutic protocol obtaining a complete resolution after one year for culture and atypical bacteria controls. This study suggests to improve the quality of laboratory diagnosis as unavoidable support to a correct clinical diagnosis and therapy, in a standardized modality both for swabbing and scraping, to check the new-born microbial programming starting in uterus, overtaking the cultural age to the molecular age, and to revise the WHO guidelines of SAFE Strategy for trachoma eye disease, transforming it into SAFES Strategy where the S letter is the acronym of Sexual ecosystem and behavioural valuation/education.

Chemotactic synthetic vesicles: Design and applications in blood-brain barrier crossing

In recent years, scientists have created artificial microscopic and nanoscopic self-propelling particles, often referred to as nano- or microswimmers, capable of mimicking biological locomotion and taxis. This active diffusion enables the engineering of complex operations that so far have not been possible at the micro- and nanoscale. One of the most promising tasks is the ability to engineer nanocarriers that can autonomously navigate within tissues and organs, accessing nearly every site of the human body guided by endogenous chemical gradients. We report a fully synthetic, organic, nanoscopic system that exhibits attractive chemotaxis driven by enzymatic conversion of glucose. We achieve this by encapsulating glucose oxidase alone or in combination with catalase into nanoscopic and biocompatible asymmetric polymer vesicles (known as polymersomes). We show that these vesicles self-propel in response to an external gradient of glucose by inducing a slip velocity on their surface, which makes them move in an extremely sensitive way toward higher-concentration regions. We finally demonstrate that the chemotactic behavior of these nanoswimmers, in combination with LRP-1 (low-density lipoprotein receptor-related protein 1) targeting, enables a fourfold increase in penetration to the brain compared to nonchemotactic systems.

Cerebrospinal fluid molecular demonstration of Chlamydia pneumoniae DNA is associated to clinical and brain magnetic resonance imaging activity in a subset of patients with relapsing-remitting multiple sclerosis

To further explore the link between Chlamydia pneumoniae and multiple sclerosis (MS), we examined cerebrospinal fluid (CSF) samples from 71 patients with MS and from 72 patients suffering from other inflammatory neurological disorders (OIND) or noninflammatory neurological disorders (NIND). All samples were analysed by a touchdown nested polymerase chain reaction (n-PCR) forC. pneumoniae with primer sets which amplify target sequence genes encoding the major outer membrane protein (MOMP), the16S rRNA and the Hsp- 70 protein. A molecular study was also performed to evaluate genetic diversity among isolates of C. pneumoniae and to compare chlamydial sequences. PCR was found positive in 36.6% of total MS, in 28.1% of OIND and in 37.5% of NIND patients, without any statistical differences among the various groups examined. CSF PCR evidence of C. pneumoniae was significantly more frequent in relapsing-remitting (RR) than in secondary progressive (SP) (PB-0.001) and in primary progressive (PP)MS (PB-0.05), in clinically active than in clinically stable MS (PB-0.05) and in MRI active than in MRI inactive MS(PB-0.001). The analysis of CSF expression of each single C. pneumoniae-specific gene revealed that detectable levels of MOMP were significantly more frequent in MS patients with relapse (PB-0.05), whereas PCR positivity for MOMP and 16S rRNA genes were more represented in MS patients with clinical and MRI evidence of disease activity (PB-0.05). Similar rates for MOMP and 16S rRNA genes were detected in CSF of both MS patients and controls, whereas CSF PCR positivity for Hsp-70 gene was observed in only three active RR MS patients. Sequence analysis revealed significant homologies withC. pneumoniae compared to otherChlamydial spp. These findings confirm that theC. pneumoniae detection within the central nervous system (CNS) is not selectively restricted to MS, but accounts in a variety of neurological diseases. In addition, our results suggest that CSF C. pneumoniae-specific DNA detection can occur in a subset of MS patients with clinical and MRI active RR form in whom a C. pneumoniae brain chronic persistent infection may play a significant role in the development of disease.

Purification of Nanoparticles by Size and Shape

Producing monodisperse nanoparticles is essential to ensure consistency in biological experiments and to enable a smooth translation into the clinic. Purification of samples into discrete sizes and shapes may not only improve sample quality, but also provide us with the tools to understand which physical properties of nanoparticles are beneficial for a drug delivery vector. In this study, using polymersomes as a model system, we explore four techniques for purifying pre-formed nanoparticles into discrete fractions based on their size, shape or density. We show that these techniques can successfully separate polymersomes into monodisperse fractions.

Cerebrospinal fluid amounts of HLA-G in dimeric form are strongly associated to patients with MRI inactive multiple sclerosis

Background:

The relevance of human leukocyte antigen (HLA)-G in dimeric form in multiple sclerosis (MS) is still unknown.

Objective:

To investigate the contribution of cerebrospinal fluid (CSF) HLA-G dimers in MS pathogenesis.

Methods:

CSF amounts of 78-kDa HLA-G dimers were measured by western blot analysis in 80 MS relapsing–remitting MS (RRMS) patients and in 81 inflammatory and 70 non-inflammatory controls.

Results:

CSF amounts of 78kDa HLA-G dimers were more frequent in RRMS than in inflammatory ( p<0.01) and non-inflammatory controls ( p<0.001) and in magnetic resonance imaging (MRI) inactive than in MRI active RRMS ( p<0.00001).

Conclusion:

Our findings suggest that HLA-G dimers may be implicated in termination of inflammatory response occurring in MS.

Overall migration and kinetics of release of antioxidant compounds from citrus extract-based active packaging

Overall migration (OM) tests were conducted on an antioxidant active packaging prepared by coating plasma pretreated and untreated polyethylene terepthalate (PET) trays with a citrus extract. The release of antioxidant compounds into food simulants was measured to permit their subtraction from OM values in line with active packaging legislation. The results demonstrated the compliance of the packaging with the limit for OM for plastic material in contact with food. The validity of the procedure for OM in aqueous food simulants was questioned, with the loss of volatile compounds during evaporation of the simulant resulting in an underestimation of total compounds released. The study showed a total release of 75% of the citrus extract coating into water and 25% into oil, which decreased to 45 and 12.5%, respectively, following plasma pretreatment of the trays.

Severe pneumonia after intravesical BCG instillation in a patient with invasive bladder cancer: case report and literature review

We present here the case of a 66 year old man with a severe bilateral community acquired pneumonia secondary to dissemination after an intravesical instillation of bacilllus Calmette-Guerin (BCG). Diagnosis was based on positive polymerase chain reaction (PCR) for mycobacterium tuberculosis complex in bronchoalveolar lavage and on the finding on transbronchial biopsy of non necrotising granulomas histopathologically similar to the granulomas found in bladder biopsies. These findings were confirmed using a validated real time PCR assay demonstrating the presence of the BCG genome in transbronchial and bladder biopsies.

[Epidemiological, social and public health aspects of tuberculosis in Ferrara in the 19th century]

Our first study of tuberculosis in Ferrara during the nineteenth century, whose results have been recently published, focused on disease treatment. Here we present the descriptive analysis of mortality, with the following results being attained: two behavioural patterns are detected with regard to the onset of disease, before and after 1850; TB is a specific disease that affects all parts of the body in all age groups: childhood, and active and passive populations; there are no significant differences with regard to gender; as regards the occupations performed by the deceased, those related to industry and agriculture and to various other activities and services are those with the highest mortality; tuberculosis has a seasonal pattern; summer and autumn are the periods of greatest prevalence (hot weather and humidity are factors that affect the respiratory system); among the forms of tuberculosis it can be observed that up to the year 1850 people died in Ferrara either of pulmonary tuberculosis or TB localised in other areas; from 1851 onward there appears to have been a dramatic change, with a decrease in unspecific diagnosis but the appearance of disease manifestations in its various clinical forms.

Redescription of the male of Ixodes festai Rondelli, 1926 (Ixodida: Ixodidae) on specimens from Sardinia (Italy)

Ixodes festai Rondelli, 1926 is a poorly known bird parasite tick. Its immature forms have not been described yet, while the adult forms only insufficiently, especially the male. In this note the presence of the male of Ixodes festai for the first time in Sardinia (Italy) is reported and a detailed redescription is provided. Morphometric data as well as photographs performed both with optical and electron microscope (ESEM FEI Quanta 200) are also shown.

Argas (Persicargas) persicus (Oken, 1818) (Ixodida: Argasidae) in Sicily with considerations about its Italian and West-Mediterranean distribution

Recently, in the province of Trapani (Western Sicily), some overwintering specimens of the argasid tick Argos (Persicargas) persicus (Oken, 1818) were observed and collected. Morphological and genetic analysis were utilized in order to reach a definitive identification. The species was found in two semi-natural sites where, having been found repeatedly, its presence does not appear accidental. Moreover the characteristics of the Sicilian findings seem to exclude a human-induced spread. This record, the first regarding Sicily and South Italy, is discussed together with the previous doubtful citations for Italy. These findings revalue not only all the old citations for Italy but also the hypothesis that the Mediterranean distribution of this argasid is of a natural origin.

Molecular detection of Parachlamydia-like organisms in cerebrospinal fluid of patients with multiple sclerosis

The presence of Chlamydia-like organism DNA was investigated by polymerase chain reaction (PCR) in cerebrospinal fluid (CSF) samples from 27 patients previously found positive for Chlamydia pneumoniae DNA: 12 with multiple sclerosis (MS), grouped according to clinical and magnetic resonance imaging (MRI) evidence of disease activity, 8 with other inflammatory neurological disorders and 7 with non-inflammatory neurological disorders. PCR evidence of Chlamydia-like organisms in CSF was observed only in two relapsing-remitting MS patients with clinical and MRI disease activity. These findings suggest a possible association between C. pneumoniae and Chlamydia-like organism brain infections as a cofactor in MS development.

Clinical and diagnostic management of toxoplasmosis in the immunocompromised patient

With the advent of the highly active antiretroviral therapy (HAART), the natural course of HIV infection has markedly changed and opportunistic infections including toxoplasmosis have declined and modified in presentation, outcome and incidence. However, TE is a major cause of morbidity and mortality especially in resource-poor settings but also a common neurological complication in some countries despite the availability of HAART and effective prophylaxis. In most cases toxoplasmosis occurs in brain and toxoplasmic encephalitis (TE) is the most common presentation of toxoplasmosis in immunocompromised patients with or without AIDS. The need of a definitive diagnosis is substantial because other brain diseases could share similar findings. Rapid and specific diagnosis is thus crucial as early treatment may improve the clinical outcome. Classical serological diagnosis is often inconclusive as immunodeficient individuals fail to produce significant titres of specific antibodies. Polymerase chain reaction (PCR) has a high diagnostic value in the acute disease, but like many 'in-house' PCR assays, suffers from lack of standardization and variable performance according to the laboratory. Molecular diagnosis of toxoplasmosis can be improved by performing real-time PCR protocols. This article summarises the clinical manifestations, diagnostic procedures and management strategies for this condition.

Detection of parvovirus B19 and Chlamydophila pneumoniae in a patient with atypical sarcoidosis

We present an elderly female patient with fever, aplastic anemia, arthralgic symptoms and atypical pneumonia. Serological and clinical findings suggested Parvovirus B19 and Chlamydophila pneumoniae infection. These supposed infections delayed the recognition of underlying sarcoidosis which definitive diagnosis was reached through a lung biopsy and histological demonstration of nonnecrotizing granulomas containing giant cells and noncaseating epithelioid cells. The present case highlights the potential difficulty to diagnose sarcoidosis in the presence of unusual infections which may complicate the course of this disease.

Survey of 2-ethylhexanoic acid in baby food

A solid-phase microextraction method was developed and used to perform a survey of 2-ethylhexanoic acid (2-EHA) in 63 samples of baby food from 13 European Union countries, as well as from Norway and Switzerland. The levels of 2-EHA did not exceed 3.4 mg kg(-1). The concentrations of 2-EHA in 53 samples (84%) were in the range between <0.1 and 0.5 mg kg(-1). Ten samples showed the presence of the compound in the range between 0.5 and 3.4 mg kg(-1). An exposure assessment showed that the intake of 2-EHA does not exceed the tolerable daily intake (TDI) for infants of 6-12 months of age except one occurrence when taking the worst-case food consumption data available and the highest level of contamination of the survey. In the other cases, the levels of 2-EHA are at 13-fold below the TDI.

Aedes albopictus in Sardinia: reappearance or widespread colonization?

The Asian tiger mosquito Aedes albopictus (Skuse, 1894) was first discovered in the South of Sardinia in October 1994, in a tyre depot not far from Cagliari-Elmas airport. Insecticide treatment was thought to have successfully eradicated the mosquito, but in 1996 and 1997 new breeding sites were discovered, a few at some distance from the first. More recently two sites have been reported in the heart of the city of Cagliari. It is not known whether the mosquito has spread from the first breeding place discovered, where treatment may not have been definitive, or whether they have been newly introduced. The recent sighting of Ae. albopictus in Olbia in the Northeast of the island tends to suggest the latter. Cagliari and Olbia are actually Sardinia's two largest sea ports of entry.

Plasminogen activator production in a rat model of Pneumocystis carinii pneumonia

Several studies have indicated that the serine protease urokinase-plasminogen-activator (uPA) is an important factor in host defense against pulmonary pathogens. To gain a better insight into the role of uPA in Pneumocystis carinii (P. carinii) pneumonia (PCP), we evaluated PA production in alveolar macrophages (AMs) obtained from rats with steroid-induced PCP. Treatment with cortisone acetate favored PCP in 91% of rats. In the bronchoalveolar lavage (BAL) samples of immunosuppressed rats both with and without PCP, we observed a decrease in uPA activity as well as a decrease in cell number. Urokinase-PA production by AMs was reduced in rats treated with cortisone alone. However, an increase in cell-associated uPA was observed in rats with PCP. This increase appears to be produced in response to P carinii infection. In fact, when AMs obtained from untreated healthy or immunosuppressed uninfected rats were challenged with P carinii, a significant increase in PA activity in cell lysates was observed, though a lower response was obtained in cortisone-treated animals. Our results suggest that healthy AMs respond to the presence of P carinii with an increase in uPA production and that this response in immunodepressed rat-AMs is partially impaired.

Efficacy of a novel reverse transcriptase-polymerase chain reaction (RT-PCR) for detecting Toxoplasma gondii bradyzoite gene expression in human clinical specimens

A reverse transcriptase-polymerase chain reaction (RT-PCR) assay, was performed to evaluate the transcription degree of bradyzoite- or tachyzoite-specific genes of Toxoplasma gondii on cerebrospinal fluid (CSF) specimens from AIDS patients with toxoplasmic encephalitis (TE), and to distinguish an asymptomatic latent infection from a reactivated disease. This method was compared with nested DNA amplification (n)-PCR. The mRNA expression of the representative T. gondii cystic matrix (MAG1) or bradyzoite-specific (SAG4) genes was investigated on CSF obtained from AIDS patients with first episode (no. 11) or relapse (no. 8) of TE. The mRNA expression of tachyzoite-specific (SAG1) gene was also studied. New designed oligonucleotide primers and probes, which identify a 212 bp fragment inside to the open reading MAG1 sequence, were employed in both RT-PCR and n-PCR assays. Oligo-dT primed cDNA synthesis appeared a suitable method for subsequent analysis by n-PCR. RT-PCR has been shown to be more sensitive and specific than n-PCR. MAG1 and SAG4 gene expression was detected in 8 (100%) and 6 (75%) patients with TE relapses, respectively, while SAG1 detected 7 (63%) patients with TE first episode. These findings suggest that RT-PCR method is able to identify the bradyzoite stage of T. gondii especially in patients who are at risk for TE relapse.

Study on immunobiology in ectoparasites of public health interest: Rhipicephalus sanguineus

The recently defined range of Mediterranean Spotted Fever (MSF) in Sardinia coincides with that of the widely studied Rickettsia conorii vector, the brown dog tick Rhipicephalus sanguineus. This tick is major vector of disease in humans, domestic and wild animals. Characteristic features of the vector with respect to their seasonal activity, abundance as well as incidence of human-tick contact and how these factors influence the incidence of MSF were studied. This paper also looks at host, pathogen and tick vector interactions, re-examining some of the immunobiological parameters involved. However, the primary objective of this research is to develop a strategy that will allow better and safer tick control.

Assessment of HIV-intrathecal humoral immune response in AIDS-related neurological disorders

Intrathecal synthesis of IgG directed to HIV antigens was investigated by antibody specific index (ASI), affinity-mediated immunoblot (AMI) and Western blot (WB) assay in a group of 88 AIDS patients of which 28 with HIV-associated neurological disorders (HAND), 13 without associated neurological disorders (WAND) and 47 with non-HIV-associated neurological disorders (non-HAND). CD4+ count was above 50 cells/mm3 (CD4+>50) in 30 and below 50/mm3 (CD4+<50) in 58 patients, respectively. A significantly higher frequency for CSF complete anti-gag profile (p<0.001), and for HIV-specific oligoclonal patterns ("mixed" pattern=p<0.01) was observed in HAND as compared to patterns from the other clinical groups. A decrease in complete anti-env, anti-pol and anti-gag reactivity was present in CSF of patients with CD4+<50 as compared to those with CD4+>50. Our findings suggest that AIDS appears to be characterized by an anti-HIV intrathecal humoral immune response which is principally directed to env products with a prevalence of oligoclonal patterns and CSF complete anti-gag profile in HIV-associated neurological involvement.