Dopaminergic signalling and behavioural alterations by Comt-Dtnbp1 genetic interaction and their clinical relevance

BACKGROUND AND PURPOSE

Cognitive and motor functions are modulated by dopaminergic signalling, which is shaped by several genetic factors. The biological effects of single genetic variants might differ depending on epistatic interactions that can be functionally multi-directional and non-linear.

EXPERIMENTAL APPROACH

We performed behavioural and neurochemical assessments in genetically modified mice and behavioural assessments and genetic screening in human patients with 22q11.2 deletion syndrome (22q11.2DS).

KEY RESULTS

Here, we confirm a genetic interaction between the Comt (catechol-O-methyltransferase, human orthologue: COMT) and Dtnbp1 (dystrobrevin binding protein 1, alias dysbindin, human orthologue: DTNBP1) genes that modulate cortical and striatal dopaminergic signalling in a manner not predictable by the effects of each single gene. In mice, Comt-by-Dtnbp1 concomitant reduction leads to a hypoactive mesocortical and a hyperactive mesostriatal dopamine pathway, associated with specific cognitive abnormalities. Like mice, in subjects with the 22q11.2DS (characterized by COMT hemideletion and dopamine alterations), COMT-by-DTNBP1 concomitant reduction was associated with analogous cognitive disturbances. We then developed an easy and inexpensive colourimetric kit for the genetic screening of common COMT and DTNBP1 functional genetic variants for clinical application.

CONCLUSIONS AND IMPLICATIONS

These findings illustrate an epistatic interaction of two dopamine-related genes and their functional effects, supporting the need to address genetic interaction mechanisms at the base of complex behavioural traits.

SINEUP non-coding RNA activity depends on specific N6-methyladenosine nucleotides

SINEUPs are natural and synthetic antisense long non-coding RNAs (lncRNAs) selectively enhancing target mRNAs translation by increasing their association with polysomes. This activity requires two RNA domains: an embedded inverted SINEB2 element acting as effector domain, and an antisense region, the binding domain, conferring target selectivity. SINEUP technology presents several advantages to treat genetic (haploinsufficiencies) and complex diseases restoring the physiological activity of diseased genes and of compensatory pathways. To streamline these applications to the clinic, a better understanding of the mechanism of action is needed. Here we show that natural mouse SINEUP AS Uchl1 and synthetic human miniSINEUP-DJ-1 are N⁶-methyladenosine (m⁶A) modified by METTL3 enzyme. Then, we map m⁶A-modified sites along SINEUP sequence with Nanopore direct RNA sequencing and a reverse transcription assay. We report that m⁶A removal from SINEUP RNA causes the depletion of endogenous target mRNA from actively translating polysomes, without altering SINEUP enrichment in ribosomal subunit-associated fractions. These results prove that SINEUP activity requires an m⁶A-dependent step to enhance translation of target mRNAs, providing a new mechanism for m⁶A translation regulation and strengthening our knowledge of SINEUP-specific mode of action. Altogether these new findings pave the way to a more effective therapeutic application of this well-defined class of lncRNAs.

Clustering spatio-temporal series of confirmed COVID-19 deaths in Europe

The impact of the COVID-19 pandemic varied significantly across different countries, with important consequences in the definition of control and response strategies. In this work, to investigate the heterogeneity of this crisis, we analyse the spatial patterns of deaths attributed to COVID-19 in several European countries. To this end, we propose a Bayesian nonparametric approach, based on mixture of Gaussian processes coupled with Dirichlet process, to group the COVID-19 mortality curves. The model provides a flexible framework for the analysis of time series data, allowing the inclusion in the clustering procedure of different features of the series, such as spatial correlations, time varying parameters and measurement errors. We evaluate the proposed methodology on the death counts recorded at NUTS-2 regional level for several European countries in the period from March 2020 to February 2021.

Life-threatening complications of streptococcal sepsis: a PICU contemporary series

Background

Life-threatening streptococcal sepsis nowadays represents an uncommon event in previously healthy infants and children. Critically ill patients suffering from severe streptococcal sepsis complications may present with pre-antibiotic era clinical pictures and require a timely clinical approach to achieve restitutio ad integrum.

Results

We report a series of four patient groups affected by an uncommon life-threatening streptococcal sepsis, each of them exhibiting some distinct features. Streptococcus Agalactiae sepsis was associated with cerebral thrombotic/ischaemic lesions, whereas severe cardiogenic shock was prominent in the Streptococcus Viridans group; Streptococcus Faecalis and β-hemolytic group A Streptococcus patients mostly reported lung complications.

Conclusions

Previous antibiotic treatments should not delay aggressive treatment in the intensive care setting. Early diagnostic suspicion, as well as appropriate and aggressive treatment provided within an intensive care setting are crucial for the clinical outcome.

Zinc Polyaleuritate Ionomer Coatings as a Sustainable, Alternative Technology for Bisphenol A-Free Metal Packaging

Sustainable coatings for metal food packaging were prepared from ZnO nanoparticles (obtained by the thermal decomposition of zinc acetate) and a naturally occurring polyhydroxylated fatty acid named aleuritic (or 9,10,16-trihydroxyhexadecanoic) acid. Both components reacted, originating under specific conditions zinc polyaleuritate ionomers. The polymerization of aleuritic acid into polyaleuritate by a solvent-free, melt polycondensation reaction was investigated at different times (15, 30, 45, and 60 min), temperatures (140, 160, 180, and 200 °C), and proportions of zinc oxide and aleuritic acid (0:100, 5:95, 10:90, and 50:50, w/w). Kinetic rate constants calculated by infrared spectroscopy decreased with the amount of Zn due to the consumption of reactive carboxyl groups, while the activation energy of the polymerization decreased as a consequence of the catalyst effect of the metal. The adhesion and hardness of coatings were determined from scratch tests, obtaining values similar to robust polymers with high adherence. Water contact angles were typical of hydrophobic materials with values ≥94°. Both mechanical properties and wettability were better than those of bisphenol A (BPA)-based resins and most likely are related to the low migration values determined using a hydrophilic food simulant. The presence of zinc provided a certain degree of antibacterial properties. The performance of the coatings against corrosion was studied by electrochemical impedance spectroscopy at different immersion times in an aqueous solution of NaCl. Considering the features of these biobased lacquers, they can be potential materials for bisphenol A-free metal packaging.

Evaluation of Kisspeptin levels in prepubertal obese and overweight children: sexual dimorphism and modulation of antioxidant levels

OBJECTIVE

Kisspeptin, neuropeptide involved in puberty beginning and regulation of pituitary-gonadal axis, has been shown to stimulate antioxidant defenses in murine models. Its levels are greater in females than males and also in obese prepubertal girls. Therefore, our aim was to evaluate sex-related differences in prepubertal obese patients and the relationships of Kisspeptin with metabolic/hormonal parameters.

PATIENTS AND METHODS

We studied Kisspeptin concentrations in 54 children (22 males and 32 females, Tanner stage 1), 5-12 ys, classified according to Cole's criteria into 17 overweight and 37 obese; 25 normal-weight children, aged 6-12 years, were studied as controls. We evaluated metabolic (glucose and insulin levels after oral glucose load, total- LDL- HDL-cholesterol, triglycerides, uric acid) and hormonal (fT3, fT4, TSH, IGF-1, leptin) parameters. Moreover, total antioxidant capacity (TAC) was evaluated by spectrophotometric method, using the system H202-metmyoglobin-ABTS. Kisspeptin levels were measured by RIA.

RESULTS

We did not find significant differences between obese and normal-weight children, but obese males presented significantly lower levels than females. Kisspeptin did not correlate with BMI, HOMA-IR, Insulin peak levels and TAC; a significant correlation was found between Kisspeptin and fT3 (r2=0.25; p=0.003) in the obese group; leptin levels, significantly greater in obese vs. overweight and control children, significantly correlated with TAC (r2=0.39; p=0.03).

CONCLUSIONS

These data suggest that both hormones could modulate antioxidants, Kisspeptin indirectly via influence on thyroid hormones, and Leptin by a direct effect. This mechanism seems to be sex-related, not attributable to peripheral steroid levels. Further studies can clarify the complex interrelationship between central and peripheral Kisspeptin secretion and oxidative stress in children obesity.

Naked-Eye Detection of Rare Point Mutations in DNA

The protocol describes a naked-eye colorimetric test for the detection of somatic point mutations in an excess of wild type DNA. The future foreseen application of the method is the identification of rare mutations in circulating cell-free DNA from liquid biopsies, with a relevance in cancer diagnostics and stratification of oncological patients for personalized therapy. As a proof of concept, the test has been designed to detect the BRAF^V600E mutation in the BRAF gene, which is important to identify the sub-group of melanoma patients that can benefit from targeted therapies with BRAF inhibitors. However, this colorimetric test can be easily generalized to other somatic mutations of clinical relevance due to the use of universal detection probes, thus providing strong potential in oncological diagnostics. The test detects 0.5% of BRAF^V600E in an excess of BRAF^WT DNA, which matches the sensitivity of some commercial instrumental assays. Such sensitivity is clinically relevant for diagnostic purposes, allowing the early identification of drug-sensitive patients. In contrast to commercial assays based on real-time PCR, this test requires minimal instrumentation and processing, as it can be performed on DNA amplified with a standard PCR (or isothermal techniques) and provides a naked-eye readout with a one-tube reaction of a few steps in only one hour. At present, the test has been used only on synthetic DNA samples. However, the latter have been designed to mimic a real sample amplified from circulating cell-free DNA, to favor the translation of the test to clinical diagnostics.

Staphylococcus Aureus Panton-Valentine Leukocidin causing hip osteomyelitis, thrombophlebitis and necrotizing pneumonia in an immuocompetent child

Panton-Valentine leukocidin (PVL) represents an important virulence factor for many strains of Staphylococcus aureus. PVL is an esotoxin causing leucocyte destruction and tissue necrosis. We report on a case of osteomyelitis involving the hip joint with thromblophlebitis complicated by necrotizing pneumonia and life-threatening septic shock. The child required advance respiratory support for 14 days with circulatory support for 7 days in ICU (intensive care unit), surgical draninage via arthrotomy of hip joint and second-line antibiotic treatment for 1 month. Among a wide literature, in Europe over half of Panton-Valentine St. Aureus (PVL-SA) is MSSA. Investigations for PVL are not always available determining an under-recognition of the episodes. Data on prevalence of PVL-SA in Italy are scarce. With this clinical report, we emphasize the recognition of clinical features that must lead to suspect PVL-SA osteomyelitis in children, providing their adequate management.

An ultrasensitive colorimetric test for the detection of somatic rare mutations in DNA

Targeted therapies for cutaneous melanoma, such as those based on specific BRAF inhibitors, have improved the treatment and enhanced the survival rate of patients who harbor the V600E point mutation in the BRAF gene. However, tissue biopsies to characterize BRAF mutation status are prone to sampling bias, due to the intrinsic heterogeneity of a tumor mass. In contrast, blood biopsies, which analyze circulating tumor DNA (ctDNA), offer the most complete and sensitive characterization of the mutation status of a tumor, provide early and more accurate diagnosis, but they require instrumental and costly molecular tests. Therefore, the development of low-cost but highly sensitive tests for the non-invasive identification of BRAFV600E mutation in ctDNA would be of great clinical utility as a routine screening for the early identification of responsive patients and the follow-up of targeted therapy's response. The present work developed a naked-eye, inexpensive, yet very specific colorimetric assay, whose sensitivity is suitable for the detection of BRAFV600E rare mutation in ctDNA. Such test potentially may detect at an early stage the mutation in the tumor mass, when the first mutated cells appear in the blood, by using minimal instrumentation and thus enabling its widespread implementation in the clinics, even in local, minimally equipped laboratories. Indeed, the test detects 0.5% of BRAFV600E in an excess of BRAFWT DNA, which matches the sensitivity of some commercial instrumental assays. Such sensitivity is thus clinically relevant for diagnostic purposes, allowing the early identification of drug-sensitive patients.

Assessment, control, and prevention of microbiological and chemical hazards in seasonal swimming pools of the Versilia district (Tuscany, central Italy)

Although in Europe the quality of swimming pools (SPs) is dictated by regulations, microbiological and chemical hazards are described in the literature. Environmental bacteria or toxic disinfection by-product (DBP) compounds may indeed be recovered in waters even after disinfection. We evaluated the water quality from 26 outdoor seasonal SPs of the Versilia district, according to requirements of Regional Decree 54R/2015. In spring 2017, supply and reinstatement waters were collected after shock hyperchlorination (10 mg/L) while in summertime, a second sampling of waters before entering the pools, as well as in the pools, was performed after SPs were open to the public. In all samples, microbiological and chemical parameters were determined as defined by Directive 98/83/EC and the Italian Health Ministry. Microbiological data were within suggested limits. The first chemical analyses showed that in 35% of the feeding-pool seawater samples, the halogenated organic compounds were higher than the maximum permissible concentrations (30 μg/L). Pool waters were then dechlorinated and re-treated with hydrogen peroxide (10 mg/L) to ensure the abatement of DBPs (from 164 ± 107 to 0.9 ± 0.8 μg/L; p = 0.002). Results highlighted the need of self-controlled procedures for the SPs waters to prevent waterborne diseases and suggested hydrogen peroxide as the most appropriate disinfection method.

Microbiological Air Quality in Heating, Ventilation and Air Conditioning Systems of Surgical and Intensive Care Areas: The Application of a Disinfection Procedure for Dehumidification Devices

International literature data report that the increase of infectious risk may be due to heating, ventilation and air conditioning (HVAC) systems contaminated by airborne pathogens. Moreover, the presence of complex rotating dehumidification wheels (RDWs) may complicate the cleaning and disinfection procedures of the HVAC systems. We evaluated the efficacy of a disinfection strategy applied to the RDW of two hospitals’ HVAC systems. Hospitals have four RDW systems related to the surgical areas (SA1 and SA2) and to the intensive and sub-intensive care (IC and sIC) units. Microbiological air and surface analyses were performed in HVAC systems, before and after the disinfection treatment. Hydrogen peroxide (12%) with silver ions (10 mg/L) was aerosolized in all the air sampling points, located close to the RDW device. After the air disinfection procedure, reductions of total microbial counts at 22 °C and molds were achieved in SA2 and IC HVAC systems. An Aspergillus fumigatus contamination (6 CFU/500 L), detected in one air sample collected in the IC HVAC system, was eradicated after the disinfection. The surface samples proved to be of good microbiological quality. The results suggest the need for a disinfection procedure to improve the microbiological quality of the complex HVAC systems, mostly in surgical and intensive care areas.

Survey on Energy Drinks consumption and related lifestyle among students of two Italian high schools

BACKGROUND

The European Food Safety Authority (EFSA) has identified some risk factors for the occurrence of side effects linked to energy drinks (EDs) consumption by young people. EDs consumption has been evaluated in a sample of students in Italy together with some aspects of their lifestyle.

METHODS

The survey was performed in two high schools from September 2016 to June 2017. 583 students between 14 to 18 years were recruited and a standard questionnaire (EFSA checklist) was used to collect information on responders characteristics, beverages consumption, EDs with alcohol, and EDs and sports.

RESULTS

Despite 350 out of 583 responders (60%) consumed EDs, only 146 out of 583 (25%) were EDs-alcohol consumers. Moreover, 208 out of 379 (55%) of all physically active adolescents reported frequent EDs consumption before sport trainings.

CONCLUSIONS

Study results highlight the need for primary prevention measures in communication campaigns and training delivered by school to limit potential health threats related to excess of EDs consumption.

Improving Cleaning and Disinfection of High-Touch Surfaces in Intensive Care during Carbapenem-Resistant Acinetobacter baumannii Endemo-Epidemic Situations

Aims: High-touch surfaces cleaning and disinfection require the adoption of effective and proper executed protocols, especially during carbapenem-resistant Acinetobacter baumannii (CRAB) endemo-epidemic situations. We evaluated the effectiveness and residual disinfectant activity of disposable pre-impregnated wipes (Modified Operative Protocol, MOP) in reducing environmental bioburden versus a two-step Standard Operative Protocol (SOP) in a 12-bed Intensive Care Unit. Methods: Five high-touch surfaces were cleaned and disinfected either according to the SOP (alcohol-based cleaning and chlorine-based disinfection) or using quaternary ammonium compounds-based disposable wipes (MOP). Sampling was performed before each procedure and at 0.5, 2.5, 4.5 and 6.5 h after (560 sites). Total viable count (TVC) was evaluated according to Italian hygiene standard (<50 CFU/24 cm²). Clinical and environmental CRAB strains isolated were genotyped. Results: On non-electromedical surfaces the difference between TVC before procedure and at each of the following times was significant only for the MOP (p < 0.05, Wilcoxon test). Using the MOP, only 7.4% (10/135) of sites showed TVC >50 CFU/24 cm² (hygiene failures) versus 18.9% (25/132) after SOP (p < 0.05, Fisher’s Exact test). On infusion pumps a higher number of hygiene failures was observed after the SOP (7/44, 15.9%) compared with the MOP (4/45, 8.9%). Genotyping highlighted a common source of infection. Conclusion: On high-touch surfaces, the use of disposable wipes by in-house auxiliary nurses may represent a more effective alternative to standard cleaning and disinfection procedure performed by outsourced cleaning services, showing effectiveness in reducing microbial contamination and residual disinfection activity up to 6.5 h.

Assessing natural mineral water microbiology quality in the absence of cultivable pathogen bacteria

Italian Directives recommend the good quality of natural mineral waters but literature data assert a potential risk from microorganisms colonizing wellsprings and mineral water bottling plants. We evaluated the presence of microorganisms in spring waters (SW) and bottled mineral waters (BMW) samples. Routine microbiological indicators, additional microorganisms like Legionella spp., Nontuberculous mycobacteria (NTM) and amoebae (FLA) were assessed in 24 SW and 10 BMW samples performing cultural and molecular methods. In 33 out of 34 samples, no cultivable bacteria ≥10 CFU/L was found. Cultivable FLA were detected in 50% of water samples. qPCR showed the presence of Legionella qPCR units in 24% of samples (from 1.1 × 10² to 5.8 × 10² qPCR units/L) and NTM qPCR units in 18% of samples (from 1 × 10² to 1 × 10⁵ qPCR units/L). Vermamoeba vermiformis and Acanthamoeba polyphaga were recovered respectively in 70% of BMW samples (counts from 1.3 × 10³ to 1.2 × 10⁵ qPCR units/L) and 42% of SW samples (from 1.1 × 10³ to 1.3 × 10⁴ qPCR units/L). Vahlkampfia spp. was detected in 42% of SW and 70% of BMW samples (from 1.2 × 10³ to 1.2 × 10⁵ qPCR units/L). Considering the presence of FLA, we underline the importance of a wider microbiological risk assessment in natural mineral waters despite the absence of cultivable bacteria.

Antibacterial Melamine Foams Decorated with in Situ Synthesized Silver Nanoparticles

A new and straightforward single-step route to decorate melamine foams with silver nanoparticles (ME/Ag) is proposed. Uniform coatings of silver nanoparticles with diameters less than 10 nm are formed in situ directly on the struts surface of the foams, after their dipping in an AgNO₃ solution. We prove that the nanoparticles are stably adhered on the foams, and that their amount can be directly controlled by the concentration of the AgNO₃ solution and the dipping time. Following this production route, ME/Ag foams can be obtained with silver content ranging between 0.2 and 18.6 wt % and excellent antibacterial performance, making them appropriate for various applications. Herein we explore the possibility to use them as antibacterial filters for water treatment, proving that they are able to remove completely Escherichia coli bacteria from water when filtered at flow rates up to 100 mL/h·cm² due to the release of less than 1 ppm of Ag⁺ ions by the foams. No bacterial regrowth was observed after further dilution of the treated water, to arrive below the safety threshold of Ag⁺ for drinking water (0.1 ppm), demonstrating the excellent bactericide performance of the ME/Ag filters.

[Legal and management issues of public health requirements for swimming pools in Regione Toscana]

In this paper we describe the laws and rules applying to swimming pools. Authorization activity title for recreational swimming pools is regulated according to articles 80 and 86 of the TULPS R.D.n°773/1931. In Regione Toscana periodic management of the hygienic requirements for swimming pools is regulated by Regional Decree 54R/2015. It requires the evaluation of physical-chemical and microbiological indicators. The law applies to structural and organizational requirements of swimming pools as well as defines responsabilities of managers.

Detection of viable but non-culturable legionella in hospital water network following monochloramine disinfection

BACKGROUND

Prevention of legionellosis remains a critical issue in healthcare settings where monochloramine (MC) disinfection was recently introduced as an alternative to chlorine dioxide in controlling Legionella spp. contamination of the hospital water network. Continuous treatments with low MC doses in some instances have induced a viable but non-culturable state (VBNC) of Legionella spp.

AIM

To investigate the occurrence of such dormant cells during a long period of continuous MC treatment.

METHODS

Between November 2010 and April 2015, 162 water and biofilm samples were collected and Legionella spp. isolated in accordance with standard procedures. In sampling sites where MC was <1.5mg/L, VBNC cells were investigated by ethidium monoazide bromide (EMA)-real-time polymerase chain reaction (qPCR) and 'resuscitation' test into Acanthamoeba polyphaga CCAP 1501/18. According to the Health Protection Agency protocol, free-living protozoa were researched in 60 five-litre water samples.

FINDINGS

In all, 136 out of 156 (87.2%) of the samples taken from sites previously positive for L. pneumophila ST269 were negative by culture, but only 47 (34.5%) negative by qPCR. Although no positive results were obtained by EMA-qPCR, four out of 22 samples associated with MC concentration of 1.3 ± 0.5mg/L showed VBNC legionella resuscitation. The presence of the amoeba A. polyphaga in the hospital water network was demonstrated.

CONCLUSION

Our study is the first report evidencing the emergence of VNBC legionella during a long period of continuous MC treatment of a hospital water network, highlighting the importance of keeping an appropriate and uninterrupted MC dosage to ensure the control of legionella colonization in hospital water supplies.

Rate of Legionella pneumophila colonization in hospital hot water network after time flow taps installation

In hospital water systems legionellae may be resistant to disinfectants in pipework, which is a problem particularly in areas where there is low flow or stagnation of water. We evaluated legionella colonization of a water network of an Italian hospital after time flow taps (TFTs) installation in proximity to dead legs. The water volume flushed was 64 L/day from May 2016, and 192 L/day from December 2016. Before TFTs installation, Legionella pneumophila sg2-14 was detected in all points (4 × 10⁴ ± 3.1 × 10⁴ cfu/L). All sites remained positive (2.9 × 10⁴ ± 1.9 × 10⁴ cfu/L) through November 2016. From December 2016 legionella persisted in one point only (2 × 10² to 6.8 × 10³ cfu/L). TFTs with chemical disinfection may reduce legionella colonization associated with dead legs.

DNA Barcoding Meets Nanotechnology: Development of a Universal Colorimetric Test for Food Authentication

Food trade globalization and the growing demand for selected food varieties have led to the intensification of adulteration cases, especially in the form of species substitution and mixing with cheaper taxa. This phenomenon has huge economic impact and sometimes even public health implications. DNA barcoding represents a well-proven molecular approach to assess the authenticity of food items, although its use is hampered by analytical constraints and timeframes that are often prohibitive for the food market. To address such issues, we have introduced a new technology, named NanoTracer, that allows for rapid and naked-eye molecular traceability of any food and requires limited instrumentation and cost-effective reagents. Moreover, unlike sequencing, this method can be used to identify not only the substitution of a fine ingredient, but also its dilution with cheaper ones.

Evaluation and control of microbial and chemical contamination in dialysis water plants of Italian nephrology wards

BACKGROUND

Patients receiving haemodialysis are exposed to a large volume of dialysis fluid. The Italian Society of Nephrology (ISN) has published guidelines and microbial quality standards on dialysis water (DW) and solutions to ensure patient safety.

AIM

To identify microbial and chemical hazards, and evaluate the quality of disinfection treatment in DW plants.

METHODS

In 2015 and 2016, water networks and DW plants (closed loop and online monitors) of nine dialysis wards of Italian hospitals, hosting 162 dialysis beds overall, were sampled on a monthly basis to determine the parameters provided by ISN guidelines. Chlorinated drinking water was desalinated by reverse osmosis and distributed to the closed loop which feeds all online monitors. Disinfection with peracetic acid was performed in all DW plants on a monthly basis.

FINDINGS

Over the 24-month study period, seven out of nine DW plants (78%) recorded negative results for all investigated parameters. Closed loop contamination with Burkholderia cepacia was detected in a DW plant from January 2015 to March 2015. Pseudomonas aeruginosa was isolated from March 2016 to May 2016 in the closed loop of another DW plant. These microbial contaminations were eradicated by shock disinfection with sodium hypochlorite and peracetic acid, followed by water flushing.

CONCLUSION

These results highlight the importance of chemical and physical methods of DW disinfection. The maintenance of control measures in water plants hosted in dialysis wards ensures a microbial risk reduction for all dialysis patients.

Experimental comparison of point-of-use filters for drinking water ultrafiltration

BACKGROUND

Waterborne pathogens such as Pseudomonas spp. and Legionella spp. may persist in hospital water networks despite chemical disinfection. Point-of-use filtration represents a physical control measure that can be applied in high-risk areas to contain the exposure to such pathogens. New technologies have enabled an extension of filters' lifetimes and have made available faucet hollow-fibre filters for water ultrafiltration.

AIM

To compare point-of-use filters applied to cold water within their period of validity.

METHODS

Faucet hollow-fibre filters (filter A), shower hollow-fibre filters (filter B) and faucet membrane filters (filter C) were contaminated in two different sets of tests with standard bacterial strains (Pseudomonas aeruginosa DSM 939 and Brevundimonas diminuta ATCC 19146) and installed at points-of-use. Every day, from each faucet, 100 L of water was flushed. Before and after flushing, 250 mL of water was collected and analysed for microbiology.

FINDINGS

There was a high capacity of microbial retention from filter C; filter B released only low Brevundimonas spp. counts; filter A showed poor retention of both micro-organisms.

CONCLUSION

Hollow-fibre filters did not show good micro-organism retention. All point-of-use filters require an appropriate maintenance of structural parameters to ensure their efficiency.

Evaluation of a modified cleaning procedure in the prevention of carbapenem-resistant Acinetobacter baumannii clonal spread in a burn intensive care unit using a high-sensitivity luminometer

BACKGROUND

Enhanced environmental cleaning practices are among the most accepted measures for controlling the spread of carbapenem-resistant Acinetobacter baumannii (CR-Ab).

AIM

To evaluate the impact of heightened cleaning on an ongoing CR-Ab outbreak in a burn intensive care unit (BICU) of an Italian teaching hospital, where chlorhexidine-60% isopropyl alcohol was applied as a complementary disinfectant on high-touch surfaces.

METHODS

Compliance with the microbial limit proposed for the BICU by AFNOR-NF-S90-351 (20 colony-forming units/100cm²) was assessed by plate count, and compared with the results obtained with intracellular adenosine triphosphate (ATP) detection. Genotyping was performed using pulsed-field gel electrophoresis.

FINDINGS

During the standard cleaning regimen, three out of 23 samples (13%) gave results over the AFNOR limit and five (21.7%) showed unacceptable ATP levels with 100 relative light units/100cm² as the benchmark limit (sensibility 86.4%, specificity 92.2%). Following improvement of the cleaning procedure, only two samples out of 50 (4%) did not satisfy the microbiological criteria and seven (14%) exceeded the ATP limit. In a successive phase, eight of 30 samples collected showed unacceptable results (27%).

CONCLUSIONS

Adding chlorhexidine-60% isopropyl alcohol as complementary disinfectant proved to be effective for reducing environmental microbial contamination, ATP levels and CR-Ab infection/colonization in patients admitted to the BICU. Real-time monitoring by ATP assay was useful for managing the cleaning schedule and reducing hospital infections, although the calculated values must be interpreted as cleanliness indicators rather than risk indicators.

Efficacy of high-dose methylprednisolone pulses in a child with noninfectious persistent pleuropericarditis revealing systemic juvenile idiopathic arthritis

Not available.

Naked-eye fingerprinting of single nucleotide polymorphisms on psoriasis patients

We report a low-cost test, based on gold nanoparticles, for the colorimetric (naked-eye) fingerprinting of a panel of single nucleotide polymorphisms (SNPs), relevant for the personalized therapy of psoriasis. Such pharmacogenomic tests are not routinely performed on psoriasis patients, due to the high cost of standard technologies. We demonstrated high sensitivity and specificity of our colorimetric test by validating it on a cohort of 30 patients, through a double-blind comparison with two state-of-the-art instrumental techniques, namely reverse dot blotting and sequencing, finding 100% agreement. This test offers high parallelization capabilities and can be easily generalized to other SNPs of clinical relevance, finding broad utility in diagnostics and pharmacogenomics.

Colonization by Legionella spp. of water networks in residential buildings of the Province of Pisa, Italy

BACKGROUND

Despite the increase of community acquired cases of legionellosis in Italy over the last years, the Italian guidelines do not give indications for prevention and control of Legionella in the hot water networks (or centralized conditioning systems) of residential buildings. We performed a survey on eight medium sized apartment buildings in the Pisa district to assess the prevalence of Legionella spp. in the water network and the respondance to drinking water requisites at the point of use, according to the Italian norms.

METHODS

For each building two hot water and three cold water samples (located at water entrance from the aqueduct network into the building pipework, at the exit from pressure autoclave, and at a remote tap) were collected.

RESULTS

Legionella was detected in 20% of residential buildings, mostly in those with a central hot water production system.

CONCLUSIONS

The study highlights a condition of potential risk for susceptible population subgroups and supports the need for measures of risk assessment and control.

Spiramycin/cotrimoxazole versus pyrimethamine/sulfonamide and spiramycin alone for the treatment of toxoplasmosis in pregnancy

OBJECTIVE

To compare the effectiviness of spiramycin/cotrimoxazole (Sp/C) versus pyrimethamine/sulfonamide (Pyr/Sul) and spiramycin alone (Spy) on mother-to-child transmission of toxoplasmosis infection in pregnancy.

STUDY DESIGN

Retrospective study of pregnant women evaluated for suspected toxoplasmosis between 1992 and 2011.

RESULT

A total of 120 mothers and their 123 newborns were included. Prenatal treatment consisted of spiramycin in 43 mothers (35%), spiramycin/cotrimoxazole in 70 (56.9%) and pyrimethamine/sulfonamide in 10 (8.1%). A trend toward reduction in toxoplasmosis transmission was found when Sp/C was compared with Pyr/Sul and particularly with Spy alone (P=0.014). In particular, Spy increased the risk of congenital infection when compared with Sp/C (odds ratio (OR) 4.368; 95% CI: 1.253 to 15.219), but there was no significant reduction when Sp/C was compared with Pyr/Sul (OR 1.83; 95% CI: 0.184 to 18.274).

CONCLUSION

The treatment based on Sp/C has significant efficacy in reducing maternal-fetal transmission of Toxoplasma gondii when compared with Pyr/Sul and particularly to Spy. Randomized controlled trials would be required.

Second generation imaging of nuclear/cytoplasmic HIV-1 complexes

The ability to visualize fluorescent HIV-1 particles within the nuclei of infected cells represents an attractive tool to study the nuclear biology of the virus. To this aim we recently developed a microscopy-based fluorescent system (HIV-IN-EGFP) that has proven valid to efficiently visualize HIV-1 complexes in the nuclear compartment and to examine the nuclear import efficiency of the virus. The power of this method to investigate viral events occurring between the cytoplasmic and the nuclear compartment is further shown in this study through the analysis of HIV-IN-EGFP in cells expressing the TRIMCyp restriction factor. In these cells the HIV-IN-EGFP complexes are not detected in the nuclear compartment, while treatment with MG132 reveals an accumulation of HIV-1 complexes in the cytoplasm. However, the Vpr-mediated transincorporation strategy used to incorporate IN fused to EGFP (IN-EGFP) impaired viral infectivity. To optimize the infectivity of the HIV-IN-EGFP, we used mutated forms of IN (E11K and K186E) known to stabilize the IN complexes and to partially restore viral infectivity in transcomplementation experiments. The fluorescent particles produced with the modified IN [HIV-IN(K)EGFP_IN(E)] show almost 30% infectivity as compared to wild-type NL4.3. Detailed confocal microscopy analysis revealed that the newly generated viral particles resulted in HIV-1 complexes significantly smaller in size, thus requiring the use of brighter fluorophores for nuclear visualization [HIV-IN(K)sfGFP_IN(E)]. The second-generation visualization system HIV-IN(K)sfGFP_IN(E), in addition to allowing direct visualization of HIV-1 nuclear entry and other viral events related to nuclear import, preserves intact viral properties in terms of nuclear entry and improved infectivity.

Long-term effects of hospital water network disinfection on Legionella and other waterborne bacteria in an Italian university hospital

OBJECTIVE AND DESIGN

Legionella control still remains a critical issue in healthcare settings where the preferred approach to health risk assessment and management is to develop a water safety plan. We report the experience of a university hospital, where a water safety plan has been applied since 2002, and the results obtained with the application of different methods for disinfecting hot water distribution systems in order to provide guidance for the management of water risk.

INTERVENTIONS

The disinfection procedures included continuous chlorination with chlorine dioxide (0.4-0.6 mg/L in recirculation loops) reinforced by endpoint filtration in critical areas and a water treatment based on monochloramine (2-3 mg/L). Real-time polymerase chain reaction and a new immunoseparation and adenosine triphosphate bioluminescence analysis were applied in environmental monitoring.

RESULTS

After 9 years, the integrated disinfection-filtration strategy significantly reduced positive sites by 55% and the mean count by 78% (P < .05); however, the high costs and the occurrence of a chlorine-tolerant clone belonging to Legionella pneumophila ST269 prompted us to test a new disinfectant. The shift to monochloramine allowed us to eliminate planktonic Legionella and did not require additional endpoint filtration; however, nontuberculous mycobacteria were isolated more frequently as long as the monochloramine concentration was 2 mg/L; their cultivability was never regained by increasing the concentration up to 3 mg/L.

CONCLUSIONS

Any disinfection method needs to be adjusted/fine-tuned in individual hospitals in order to maintain satisfactory results over time, and only a locally adapted evidence-based approach allows assessment of the efficacy and disadvantages of the control measures.

Antitoxin use and pediatric intensive care for viper bites in Rome, Italy

In Italy viper bites represent an uncommon event, though envenomation can cause severe complications, more in children than adults, because of dose/body size ratio. We present a case series within a selected population: 10 Italian cases (from Rome surroundings) of viperbites requiring PICU admission, over a 5-year interval. Five children showed a systemic involvement, whereas the remaining patients showed a damage. All were managed and closely monitored in an ICU setting. Relevant clinical findings and therapeutic approach, ICU course and complications have been recorded. Age range was 3-15 years with mean age of 6,9 (SD±4,58) years; 2 patients needed respiratory support beyond oxygen supplementation. Most patients underwent fluid loading, while hemodynamic support was given to4/10. Median PICU stay was 60 hours (IQR=24.0-75.5). No mortality was reported. Indications and precautions for administration of antivenom in the last years have been reviewed: early treatment seems to reduce mortality/morbidity, though representing a threat for children. Current recommendations for the treatment of viper envenomation have been described, based on a literature's review and the application of these knowledges to clinical reality of our PICUs. Therefore, paediatric patients with systemic or rapidly evolving symptoms should be monitored carefully for the development of bite-related complications in an ICU setting mostly in younger children.

Gold-nanoparticle-based colorimetric discrimination of cancer-related point mutations with picomolar sensitivity

Point mutations in the Kirsten rat sarcoma viral oncogene homologue (KRAS) gene are being increasingly recognized as important diagnostic and prognostic markers in cancer. In this work, we describe a rapid and low-cost method for the naked-eye detection of cancer-related point mutations in KRAS based on gold nanoparticles. This simple colorimetric assay is sensitive (limit of detection in the low picomolar range), instrument-free, and employs nonstringent room temperature conditions due to a combination of DNA-conjugated gold nanoparticles, a probe design which exploits cooperative hybridization for increased binding affinity, and signal enhancement on the surface of magnetic beads. Additionally, the scheme is suitable for point-of-care applications, as it combines naked-eye detection, small sample volumes, and isothermal (PCR-free) amplification.

Ductopenia and fetal liver-like architecture as unique and evocative sign of Turner syndrome

BACKGROUND

Turner syndrome is the most common genetic disorder in females. In most subjects, with a normal physical appearance at birth, the diagnosis is suspected long after birth because of short stature, delayed puberty, primary or secondary amenorrhea or infertility. Abnormalities of liver function tests are reported in literature, with a prevalence ranging from 20% to 80%. In most subjects liver diseases are self-limiting, associated with obesity, hormonal therapy and autoimmune diseases. An association between Turner syndrome and cryptogenic liver disease has been reported. Abnormalities of liver function tests could be the unique sign of Turner syndrome in subjects with normal phenotypes. The histological picture of "fetal liver-like architecture" and "ductopenia" is of fundamental importance for the diagnosis of chromosomopathy.

AIM

Review the causes of hypertransaminasemia by focusing on more rare as metabolic and genetic diseases.

MATERIALS AND METHODS

We evaluated a 10 year old girl with a normal phenotype affected by chronic hypertransaminasemia and cholestasis, in whom a needle liver biopsy was performed after the most common causes of hypertransaminasemia were excluded.

RESULTS

Liver histological evaluation revealed a smoldering colangiopathy with mild ductopenia and a fetal liver-like architecture. Turner syndrome, suspected on the basis of this histological picture, was confirmed by a pelvic ultrasound and a chromosome analysis.

CONCLUSIONS

The histological features of "fetal liver-like architecture" and "ductopenia" represent an evocative sign that could indicate the diagnostic suspicion of Turner syndrome in a subject lacking in signs or symptoms of this disease. It is important to perform a pelvic ultrasound and an endocrinological evaluation in all females with chronic asymptomatic hypertransaminasemia even though they have normal phenotypes.

Current practice and recent advances in pediatric pain management

BACKGROUND

Differently from the adult patients, in pediatric age it is more difficult to assess and treat efficaciously the pain and often this symptom is undertreated or not treated. In children, selection of appropriate pain assessment tools should consider age, cognitive level and the presence of eventual disability, type of pain and the situation in which it is occurring. Improved understanding of developmental neurobiology and paediatric analgesic drugs pharmacokinetics should facilitate a better management of childhood pain.

AIM

The objective of this review is to discuss current practice and recent advances in pediatric pain management.

METHODS

Using PubMed we conducted an extensive literature review on pediatric pain assessment and commonly used analgesic agents from January 2000 to January 2012.

CONCLUSIONS

A multimodal analgesic regimen provides better pain control and functional outcome in children. Cooperation and communication between the anaesthesiologist, surgeon, and paediatrician are essential for successful anaesthesia and pain management.

Congenital cytomegalovirus infection: current strategies and future perspectives

INTRODUCTION

Cytomegalovirus is the most common cause of congenital infections in humans and it produces considerable morbidity in newborns.

AIMS

The present study reviews current concepts on epidemiology, clinical manifestations, diagnosis, treatment, future strategies and prognosis of children with congenital cytomegalovirus infection.

RESULTS

Congenital cytomegalovirus infection can be symptomatic or not at birth, but about 10-20% of them all will exhibit neurological damage when followed up. Sensorineural hearing loss is the most frequent long-term consequence and is not manifest invariably at birth or in the neonatal period but in many cases becomes clinically apparent in later childhood. There are growing evidences that newborns with symptomatic congenital cytomegalovirus infection would benefit from treatment with either ganciclovir or valganciclovir, the most widely studied drugs in this setting. It is not yet clear if children with asymptomatic or pauci-symptomatic infection at birth would benefit from treatment.

DISCUSSION

Studies evaluating treatment and long-term follow-up of infants with both symptomatic and asymptomatic infection are necessary, in order to definitely evaluate the short and long-term effectiveness and safety of both ganciclovir and valganciclovir and to identify risk factors associated to the development of long-term sequelae. In this way it will be possible to select those children that might benefit for treatment.

Side Effects of the Immune System: Lessons from Tuberculosis-Related Immune Reconstitution Inflammatory Syndrome

Immune reconstitution inflammatory syndrome (IRIS) is a recently described syndrome among human immunodeficiency virus (HIV)-infected patients attributable to the recovery of the immune system during antiretroviral therapy. A growing number of researches on this syndrome have been conducted in recent years, but IRIS in children has not been widely studied. We report the case of a 4.5 month-old, tuberculosis (TB)-HIV co-infected girl who developed IRIS two months after beginning antiretroviral and anti-TB medications. We moreover review the immunopathogenesis of TB-HIV coinfection and IRIS, with particular regard to TB-related IRIS.