Natural History of Aerosol-Induced Ebola Virus Disease in Rhesus Macaques

Ebola virus disease (EVD) is a serious global health concern because case fatality rates are approximately 50% due to recent widespread outbreaks in Africa. Well-defined nonhuman primate (NHP) models for different routes of Ebola virus exposure are needed to test the efficacy of candidate countermeasures. In this natural history study, four rhesus macaques were challenged via aerosol with a target titer of 1000 plaque-forming units per milliliter of Ebola virus. The course of disease was split into the following stages for descriptive purposes: subclinical, clinical, and decompensated. During the subclinical stage, high levels of venous partial pressure of carbon dioxide led to respiratory acidemia in three of four of the NHPs, and all developed lymphopenia. During the clinical stage, all animals had fever, viremia, and respiratory alkalosis. The decompensatory stage involved coagulopathy, cytokine storm, and liver and renal injury. These events were followed by hypotension, elevated lactate, metabolic acidemia, shock and mortality similar to historic intramuscular challenge studies. Viral loads in the lungs of aerosol-exposed animals were not distinctly different compared to previous intramuscularly challenged studies. Differences in the aerosol model, compared to intramuscular model, include an extended subclinical stage, shortened clinical stage, and general decompensated stage. Therefore, the shortened timeframe for clinical detection of the aerosol-induced disease can impair timely therapeutic administration. In summary, this nonhuman primate model of aerosol-induced EVD characterizes early disease markers and additional details to enable countermeasure development.

Impact of new operational dosimetric quantities on individual monitoring services

The new operational dosimetric quantities framework, proposed in the ICRU95 report, has stimulated the scientific community to start investigations that aim to assess its impact on radiation protection practices. As part of this effort, the present study describes an inter-comparison exercise among individual monitoring services (IMSs) on passive whole-body dosimetry. The inter-comparison is performed in terms of both the existing operational dose quantityHp(10)and its proposed replacementHp, to allow an evaluation of the actions that may be necessary to adapt dosimetry systems to the proposed quantity. For two of the tested IMSs, simple modifications to the detector response function, or the dose calculation algorithm, were sufficient to obtain results within acceptable limits. However, these approaches are not sufficient to give a level of performance comparable to that achieved in terms ofHp(10). This may require a modification to dosemeter design.

Molecular detection of HEV in domestic pigs in Italy from Abruzzo and Molise regions

Background

Hepatitis E virus (HEV) is a zoonotic pathogen transmitted through the faecal-oral route and it is responsible of disease in humans with more than 21.000 cases reported in the European Union (EU) over the last decade. It is a non-enveloped single stranded RNA virus that includes 8 genotypes; among these, genotypes 3 and 4 (HEV-3 and HEV-4) are the most prevalent in developed countries and infect both humans and some animal species such as domestic pigs. In this study, we investigated the prevalence of HEV in domestic pigs bred in Italy, in Abruzzo and Molise regions.

Methods

During the period October 2020-March 2021, 327 liver samples from individual pigs were analysed. In particular, 211 were collected in 1 slaughterhouse and originated from animals bred in Abruzzo in 8 different farms and 116 were collected in 7 slaughterhouses and originated from animals bred in Molise in 47 farms. The real time retro-transcriptase (RT)-polymerase chain reaction (PCR) technique was used to detect HEV by targeting the open reading frame (ORF) 3 region of the viral ribonucleic acid (RNA).

Results

None of the samples deriving from pigs bred in Abruzzo tested positive for the detection of HEV RNA. Instead, 4 samples from pigs bred in 2 different farms in Molise tested positive, showing a prevalence of 3.45%.

Conclusions

Pigs are considered important reservoirs for HEV virus. For this reason, it is opportune to investigate the role of these animals for better understanding their involvement in the human infection through the consumption of contaminated raw or undercooked pork-meat products. These findings need to be further investigated with in depth genomic characterization of positive RNA samples to highlight the role of the specific strains circulating in this region and to draw conclusions about connections between animals, potential contaminated food and human disease.

Key messages

The study paved the way for defining the role of pigs in the transmission of HEV virus to humans through the consumption of pork meat products. This study reports the prevalence of HEV in domestic pigs of Abruzzo and Molise regions, two Italian regions.

Detecting Pathogen Exposure During the Non-symptomatic Incubation Period Using Physiological Data: Proof of Concept in Non-human Primates

Background and Objectives: Early warning of bacterial and viral infection, prior to the development of overt clinical symptoms, allows not only for improved patient care and outcomes but also enables faster implementation of public health measures (patient isolation and contact tracing). Our primary objectives in this effort are 3-fold. First, we seek to determine the upper limits of early warning detection through physiological measurements. Second, we investigate whether the detected physiological response is specific to the pathogen. Third, we explore the feasibility of extending early warning detection with wearable devices.

Research Methods: For the first objective, we developed a supervised random forest algorithm to detect pathogen exposure in the asymptomatic period prior to overt symptoms (fever). We used high-resolution physiological telemetry data (aortic blood pressure, intrathoracic pressure, electrocardiograms, and core temperature) from non-human primate animal models exposed to two viral pathogens: Ebola and Marburg (N = 20). Second, to determine reusability across different pathogens, we evaluated our algorithm against three independent physiological datasets from non-human primate models (N = 13) exposed to three different pathogens: Lassa and Nipah viruses and Y. pestis. For the third objective, we evaluated performance degradation when the algorithm was restricted to features derived from electrocardiogram (ECG) waveforms to emulate data from a non-invasive wearable device.

Results: First, our cross-validated random forest classifier provides a mean early warning of 51 ± 12 h, with an area under the receiver-operating characteristic curve (AUC) of 0.93 ± 0.01. Second, our algorithm achieved comparable performance when applied to datasets from different pathogen exposures – a mean early warning of 51 ± 14 h and AUC of 0.95 ± 0.01. Last, with a degraded feature set derived solely from ECG, we observed minimal degradation – a mean early warning of 46 ± 14 h and AUC of 0.91 ± 0.001.

Conclusion: Under controlled experimental conditions, physiological measurements can provide over 2 days of early warning with high AUC. Deviations in physiological signals following exposure to a pathogen are due to the underlying host’s immunological response and are not specific to the pathogen. Pre-symptomatic detection is strong even when features are limited to ECG-derivatives, suggesting that this approach may translate to non-invasive wearable devices.

Critical points and potential pitfalls of outbreak of IMP-1-producing carbapenem-resistant Pseudomonas aeruginosa among kidney transplant recipients: a case-control study

BACKGROUND

Carbapenem-resistant Pseudomonas aeruginosa (CRPA) infection after kidney transplantation (KT) is associated with high mortality.

AIM

To analyse an outbreak of infection/colonization with IMP-1-producing CRPA on a KT ward.

METHODS

A case-control study was conducted. Cases were identified through routine surveillance culture and real-time polymerase chain reaction for carbapenemase performed directly from rectal swab samples. Controls were randomly selected from patients hospitalized on the same ward during the same period, at a ratio of 3:1. Strain clonality was analysed through pulsed-field gel electrophoresis (PFGE), and whole-genome sequencing was performed for additional strain characterization.

FINDINGS

CRPA was identified in 37 patients, in 51.4% through surveillance cultures and in 49.6% through clinical cultures. The median persistence of culture positivity was 42.5 days. Thirteen patients (35.1%) presented a total of 15 infections, of which seven (46.7%) were in the urinary tract; among those, 30-day mortality rate was 46.2%. PFGE analysis showed that all of the strains shared the same pulsotype. Multilocus sequence typing analysis identified the sequence type as ST446. Risk factors for CRPA acquisition were hospital stay >10 days, retransplantation, urological surgical reintervention after KT, use of carbapenem or ciprofloxacin in the last three months and low median lymphocyte count in the last three months.

CONCLUSION

KT recipients remain colonized by CRPA for long periods and could be a source of nosocomial outbreaks. In addition, a high proportion of such patients develop infection. During an outbreak, urine culture should be added to the screening protocol for KT recipients.

Effectiveness and safety of 1L PEG-ASC preparation for colonoscopy in patients with inflammatory bowel diseases

INTRODUCTION

The effectiveness of bowel cleansing is a key element for high-quality colonoscopy. Recently, a 1 L polyethylene glycol plus ascorbate (PEG-ASC) solution has been introduced, but effectiveness and safety of this preparation have not been assessed in IBD patients. This study aims to evaluate effectiveness and safety of 1 L PEG-ASC solution in patients with IBD compared to controls.

METHODS

We retrospectively analysed prospectively collected data on a cohort of 411 patients performing a colonoscopy after preparation with 1 L PEG-ASC, consecutively enrolled in 5 Italian centres.

RESULTS

Overall, 185/411 (45%) were patients with IBD and 226/411 (55%) served as controls. A significantly higher cleansing success was achieved in IBD patients (92.9% vs 85.4%, p = 0.02). The multiple regression model showed that presence of IBD (OR=2.514, 95%CI=1.165-5.426; P = 0.019), lower age (OR=0.981, 95%CI=0.967-0.996; P = 0.014), split preparation (OR=2.430, 95%CI=1.076-5.492; P = 0.033), absence of diabetes (OR=2.848, 95%CI=1.228-6.605; P = 0.015), and of chronic constipation (OR=3.350, 95%CI=1.429-7.852; P = 0.005), were independently associated with cleansing success. The number of treatment-emergent adverse events (TEAEs) (51 vs 62%, p = 0.821), and of patients with TEAEs (22.2% vs 21.2%, p = 0.821), were similar in IBD patients and in controls, respectively.

CONCLUSIONS

Results from this study support the effectiveness and safety of 1 L PEG-ASC solution in IBD patients, which may improve the definition of endoscopic outcomes both in Crohn's disease and ulcerative colitis.

The Clean Care Contest: promoting hand hygiene among healthcare and medical students

INTRODUCTION

Despite continuing efforts, compliance rates and knowledge of best practices in hand hygiene remain disappointing. Recognizing that conventional educational tools seem out of touch with young people and that the med and messages contents need refreshing, the Italian Study Group of Hospital Hygiene of the Italian Society of Hygiene, Preventive Medicine and Public Health devised a novel approach to promote the creation of innovative educational tools for improving knowledge of, and compliance with, hand hygiene rules among healthcare and medical students.

METHODS

A contest in creating educational material on hand hygiene practices involved university students of nursing and medicine, and of other healthcare degrees. Students from the universities of the GISIO network were invited to create educational material (e.g., videos, posters, presentations, leaflets, and screensavers) to be presented by May 5th 2019 during the World Hand Hygiene Day / Save Lives: Clean Your Hands Global Annual Initiative of the World Health Organization). A local and a national winners were awarded.

RESULTS

Three different local and national contests were performed during 2016, 2017 and 2018. During the three-year period, more than 270 educational tools have been developed: 130 (48%) were judged useful for hand hygiene promotion campaigns. The most frequent projects participating in the contests were videos (39%), posters (29%), leaflets (14%), and others (18%) submitted by more than 1,500 students of nursing (40%), medicine (31%), dentistry (7%), and of other healthcare courses in 14 universities. Products were evaluated by a local committee and, subsequently, local winners represented their University in a national contest.

CONCLUSIONS

The contest provided a framework for the creation of innovative and potentially effective educational tools via an engaging approach that leveraged student creativity. Given the need to improve compliance rates, this study suggests that new ways can be advantageously explored to teach hand hygiene procedures and increase awareness of the importance of their consistent use among healthcare and medical students.

Intensive Care Unit-Like Care of Nonhuman Primates with Ebola Virus Disease

BACKGROUND

Ebola virus disease (EVD) supportive care strategies are largely guided by retrospective observational research. This study investigated the effect of EVD supportive care algorithms on duration of survival in a controlled nonhuman primate (NHP) model.

METHODS

Fourteen rhesus macaques were challenged intramuscularly with a target dose of Ebola virus (1000 plaque-forming units; Kikwit). NHPs were allocated to intensive care unit (ICU)-like algorithms (n = 7), intravenous fluids plus levofloxacin (n = 2), or a control group (n = 5). The primary outcome measure was duration of survival, and secondary outcomes included changes in clinical laboratory values.

RESULTS

Duration of survival was not significantly different between the pooled ICU-like algorithm and control groups (8.2 vs 6.9 days of survival; hazard ratio; 0.50; P = .25). Norepinephrine was effective in transiently maintaining baseline blood pressure. NHPs treated with ICU-like algorithms had delayed onset of liver and kidney injury.

CONCLUSIONS

While an obvious survival difference was not observed with ICU-like care, clinical observations from this model may aid in EVD supportive care NHP model refinement.

Gold nanoparticle assisted synthesis of MoS2 monolayers by chemical vapor deposition

The use of metal nanoparticles is an established paradigm for the synthesis of semiconducting one-dimensional nanostructures. In this work we study their effect on the synthesis of two-dimensional semiconducting materials, by using gold nanoparticles for chemical vapor deposition growth of two-dimensional molybdenum disulfide (MoS2). In comparison with the standard method, the employment of gold nanoparticles allows us to obtain large monolayer MoS2 flakes, up to 20 μm in lateral size, even if they are affected by the localized overgrowth of MoS2 bilayer and trilayer islands. Important modifications of the optical and electronic properties of MoS2 triangular domains are reported, where the photoluminescence intensity of the A exciton is strongly quenched and a shift to a positive threshold voltage in back-gated field effect transistors is observed. These results indicate that the use of gold nanoparticles influences the flake growth and properties, indicating a method for possible localized synthesis of two-dimensional materials, improving the lateral size of monolayers and modifying their properties.

Ocrelizumab in a case of refractory chronic inflammatory demyelinating polyneuropathy with anti-rituximab antibodies

Rituximab (RTX), a chimeric anti-CD20 monoclonal antibody, has demonstrated good efficacy as treatment in patients with resistant chronic inflammatory demyelinating polyradiculoneuropathy (CIDP), but it is highly immunogenic due to its structure. Ocrelizumab (OCR) is a humanized anti-CD20 antibody, with higher tolerability and a lower immunogenic profile compared to RTX. We present a case of refractory CIDP effectively treated with OCR, switched from RTX after the development of anti-drug antibodies. A 25-year-old man was admitted to our clinic for the onset of distal upper and lower limb weakness and numbness, with electrodiagnostic criteria of CIDP. After several attempted standard CIDP treatments, RTX was introduced due to poor control of clinical relapses. Unfortunately, the patient developed a high anti-drug antibody titer after RTX infusion, with no control of disease. OCR was started as an off-label treatment, resulting in partial recovery from the last recurrence and achieving good prevention of new relapses with no adverse events. We suggest that OCR should be considered as another therapeutic option in refractory CIDP. In the literature, this is the first case of CIDP treated with OCR, demonstrating good efficacy for its anti-CD20 effect and better tolerability because of its lower immunogenicity.

Acute toxic exposures in children: analysis of a three year registry managed by a Pediatric poison control Center in Italy

Introduction

Acute pediatric poisoning is an emerging health and social problem. The aim of this study is to describe the characteristics of a large pediatric cohort exposed to xenobiotics, through the analysis of a Pediatric Poison Control Center (PPCc) registry.

Methods

This study, conducted in the Pediatric Hospital Bambino Gesù of Rome, a reference National Pediatric Hospital, collected data of children whose parents or caregivers contacted the PPCc by phone (group “P”), or who presented to the Emergency Department (group “ED”), during the three-year period 2014–2016. Data were prospectively and systematically collected in a pre-set electronic registry. Comparisons among age groups were performed and multivariable logistic regression models used to investigate associations with outcomes (hospital referral for “P”, and hospital admission for “ED”group).

Results

We collected data of 1611 children on group P and 1075 on group ED. Both groups were exposed to both pharmaceutical and non-pharmaceutical agents. Pharmaceutical agent exposure increased with age and the most common route of exposure was oral. Only 10% among P group were symptomatic children, with gastrointestinal symptoms. Among the ED patients, 30% were symptomatic children mostly with gastrointestinal (55.4%) and neurologic symptoms (23.8%). Intentional exposure (abuse substance and suicide attempt), which involved 7.7% of patients, was associated with older age and Hospital admission.

Conclusions

Our study describes the characteristics of xenobiotics exposures in different paediatric age groups, highlighting the impact of both pharmacological and intentional exposure. Furthermore, our study shows the utility of a specific PPCc, either through Phone support or by direct access to ED. PPCc phone counselling could avoid unnecessary access to the ED, a relevant achievement, particularly in the time of a pandemic.

Pain distraction during awake low anterior resection and Cuddle Delivery initiative for inpatient: frugal procedural options to support surgery in the COVID-19 era

OBJECTIVE

Since minimally invasive surgery and general anesthesia are both aerosol-generating procedures, their use became controversial during the outbreak of coronavirus disease 2019 (COVID-19). Moreover, social distancing resulted in serious psychological consequences for inpatients. This case report investigates pain distraction during awake laparotomy, as well as new possibilities for emotional postoperative support to inpatients.

PATIENTS AND METHODS

A 72-year-old man affected by middle rectal adenocarcinoma underwent lower anterior resection plus total mesorectal excision under combined spinal-epidural anesthesia. A 3D mobile theatre (3DMT) was intraoperatively used for pain distraction. A postoperative "Cuddle delivery" service was instituted: video-messages from relatives and close friends were delivered daily to the patient through the 3DMT. Emotional correlations were investigated through a clinical interview by the psychologist of our Hospital.

RESULTS

Intraoperative, as well as postoperative pain, resulted well-controlled: visual analogue scale (VAS) ≤3. Conversion to general anesthesia and postoperative intensive support/monitoring were unnecessary. The "Cuddle delivery" initiative positively fed our patient's mood and attitude, strengthening his bond to life.

CONCLUSIONS

During pandemic, awake laparotomy under loco-regional anesthesia may be a crucial option in delivering acute care surgery to selected patients when intensive care beds are unavailable. Our procedure introduces potential ways to optimize this approach.

Improved experimental evaluation and model validation of a 252Cf irradiator for delayed gamma-ray spectrometry applications

We present experimental and MCNP modeled results of neutron flux monitoring in an irradiator, which consists of a²⁵²Cf sealed source housed in the center of a cubic block of high-density polyethylene. This work is contributing to our development in the delayed gamma-ray spectroscopy non-destructive assay technique for nuclear safeguards and security applications. We evaluated the thermal and resonance flux values using the Westcott foil activation method for two measurement position count rates of ¹⁹⁷Au and ¹¹⁵In. Comparisons between the calculated thermal fluxes from measurements and those from MCNP models show deviations of ~20%. However, both the measured and modeled thermal fluxes are two orders of magnitude higher than the fluxes at the resonance peak energies at both measurement positions, demonstrating that the irradiator is sufficient. Furthermore, this work showed that with a²⁵²Cf sealed source of a strength of 4.4 × 10⁶ n.s^-1, a thermal flux in the range 2-5 × 10⁴ n.s^-1.cm^-2 is achievable in our compact irradiator making it suitable for active analysis techniques such as DGS.

Deterministic synthesis of Cu9S5 flakes assisted by single-layer graphene arrays

The employment of two-dimensional materials, as growth substrates or buffer layers, enables the epitaxial growth of layered materials with different crystalline symmetries with a preferential crystalline orientation and the synthesis of heterostructures with a large lattice constant mismatch. In this work, we employ single crystalline graphene to modify the sulfurization dynamics of copper foil for the deterministic synthesis of large-area Cu₉S₅ crystals. Molecular dynamics simulations using the Reax force-field are used to mimic the sulfurization process of a series of different atomistic systems specifically built to understand the role of graphene during the sulphur atom attack over the Cu(111) surface. Cu₉S₅ flakes show a flat morphology with an average lateral size of hundreds of micrometers. Cu₉S₅ presents a direct band-gap of 2.5 eV evaluated with light absorption and light emission spectroscopies. Electrical characterization shows that the Cu₉S₅ crystals present high p-type doping with a hole mobility of 2 cm² V^-1 s^-1.

Evaluating the plasmon-exciton interaction in ZnO tetrapods coupled with gold nanostructures by nanoscale cathodoluminescence

Plasmon-exciton coupling is gaining increasing interest for enhancing the performance of optoelectronic, photonic and photo-catalytic devices. Herein we evaluate the interaction of excitons in zinc oxide tetrapods with surface plasmons of gold nanostructures with different morphologies. The gold nanostructures are grown in situ on ZnO tetrapods by means of a photochemical process, resulting in clean interfaces. The modification of the synthesis parameters results in different morphologies, as isolated nanoparticles, nano-domes or nanoparticles aggregates. Plasmon-exciton interaction is evaluated by means of cathodoluminescence spectroscopy and mapping at the nanoscale. The ZnO excitonic emission is strongly blue-shifted and broadened in close proximity of the gold nanostructures. This effect is explained by the formation of a Schottky barrier that is strongly mediated by the morphology of metal nanostructures.

Fluoroquinolone treatment as a protective factor for 10-day mortality in Streptococcus pneumoniae bacteremia in cancer patients

To evaluate the prognostic factors in adult cancer patients with pneumococcal bacteremia, describe episode features and the phenotypic characteristics of the isolated strains. We evaluated the episodes in patients admitted to a cancer hospital between 2009 and 2015. The outcomes were defined as 48 h mortality and mortality within 10 days after the episode. The variables evaluated were: age, sex, ethnicity, ECOG, Karnofsky score, SOFA, cancer type, metastasis, chemotherapy, radiotherapy, neutropenia, previous antibiotic therapy, community or healthcare-acquired infection, comorbidities, smoking, pneumococcal vaccination, infection site, presence of fever, polymicrobial infection, antimicrobial susceptibility, serotype and treatment. 165 episodes were detected in 161 patients. The mean age was 61.3 years; solid tumors were the most prevalent (75%). 48 h and 10-day mortality were 21% (34/161) and 43% (70/161) respectively. The 48 h mortality- associated risk factors were SOFA and polymicrobial bacteremia; 10-day mortality-associated risk factors were fever, neutropenia, ECOG 3/4, SOFA and fluoroquinolones as a protective factor. Pneumococcal bacteremia presented high mortality in cancer patients, with prognosis related to intrinsic host factors and infection episodes features. Fluoroquinolone treatment, a protective factor in 10-day mortality, has potential use for IPDs and severe community-acquired pneumonia in cancer patients.

Development of a coronavirus disease 2019 nonhuman primate model using airborne exposure

Airborne transmission is predicted to be a prevalent route of human exposure with SARS-CoV-2. Aside from African green monkeys, nonhuman primate models that replicate airborne transmission of SARS-CoV-2 have not been investigated. A comparative evaluation of COVID-19 in African green monkeys, rhesus macaques, and cynomolgus macaques following airborne exposure to SARS-CoV-2 was performed to determine critical disease parameters associated with disease progression, and establish correlations between primate and human COVID-19. Respiratory abnormalities and viral shedding were noted for all animals, indicating successful infection. Cynomolgus macaques developed fever, and thrombocytopenia was measured for African green monkeys and rhesus macaques. Type II pneumocyte hyperplasia and alveolar fibrosis were more frequently observed in lung tissue from cynomolgus macaques and African green monkeys. The data indicate that, in addition to African green monkeys, macaques can be successfully infected by airborne SARS-CoV-2, providing viable macaque natural transmission models for medical countermeasure evaluation.