Radiation Therapy Generates Release of Microvesicle Particles in Keratinocytes

PURPOSE/OBJECTIVE(S)

Ionizing radiation (IR) exerts both tissue and systemic effects. However, the exact mechanism by which radiation therapy to skin results in local and systemic effects is incompletely defined. Previously our group has reported that IR of tumors results in the generation of the lipid mediator Platelet-activating factor (PAF) which resulted in systemic immunosuppressive effects via activation of regulatory T cells. Since PAF acting on the PAF receptor (PAFR) has been demonstrated to generate high levels of subcellular microvesicle particles (100-1000nm; MVP), and MVP are known to be able to signal systemically, the current studies seek to define whether IR of keratinocyte cells generates MVP, and to define the role of the PAFR in this process. Thus, we examine MVP release in the human keratinocyte cell line HaCaT. Moreover, the PAFR-dependency of IR-generated MVP is assessed by use of PAFR-positive KBP and PAFR-negative KBM cells.

MATERIALS/METHODS

HaCaT cells (human keratinocytes), KBM cells (PAFR-negative), and KBP cells (PAFR-positive) were grown in 10cm dishes and treated with IR at either no treatment 0 Gy (NT), 4 Gy and 10 Gy. IR was delivered utilizing a technology company's medical linear accelerator radiotherapy system set up with dosimetry verified by nanodot optical stimulated luminescence (Landauer, Glenwood, IL). Some cell lines were treated with PAFR agonist N-methyl carbamoyl PAF (CPAF) and a phorbol ester TPA, known inducers of MVP release. A set of cells were treated with only 90% DMSO/10% ethanol vehicle in HBSS with BSA. After treatments, cells were incubated for 4 hours prior to extraction of MVPs. MVPs were isolated through centrifuging at 2000G for 20, supernatant was collected, transferred into different tubes, and centrifuged at 20,000 G for 70 mins. MVP was detected using a NanoSight NS300 instrument. MVP concentrations were recorded, and the data was statistically analyzed using Student's t-test (JMP, Cary, NC).

RESULTS

IR treatment of HaCaT cells at various fluences exhibited statistically significant increases in MVP generation when compared to NT. Of note, 4 Gy resulted in the most fluence for MVP release but was not significant. IR treatment of KB cells resulted in MVP release in both KBM and KBP cells at both 4 and 10Gy. Augmented levels of MVP release were noted in KBP over KBM cells with any IR dose suggesting that the presence of the PAFR is involved in MVP release. Testing of inhibitors of the MVP generating enzyme acid sphingomyelinase (aSMase) also revealed involvement of this lipid metabolizing enzyme.

CONCLUSION

The present studies indicate that RT can generates MVP production in epithelial cells. The mechanism for IR-generated MVP appears to involve aSMase and the PAFR. Target cell MVP release may provide a mechanism for RT effects, including the release of cytokines that influence systemic and local inflammation. Elucidation of this novel pathway may provide insights into IR effects on skin along with new therapeutic strategies.

Technical note: Understanding the effect of COVID-19 on particle pollution using a low-cost sensor network

The 2020 coronavirus pandemic and the following quarantine measures have led to significant changes in daily life worldwide. Preliminary research indicates that air quality has improved in many urban areas as a result of these measures. This study takes a neighborhood-scale approach to quantifying this change in pollution. Using data from a network of citizen-hosted, low-cost particulate matter (PM) sensors, called Air Quality & yoU (AQ&U), we obtained high-spatial resolution measurements compared to the relatively sparse state monitoring stations. We compared monthly average estimated PM_2.5 concentrations from February 11 to May 11, 2019 at 71 unique locations in Salt Lake County, UT, USA with the same (71) sensors' measurements during the same timeframe in 2020. A paired t-test showed significant reductions (71.1% and 21.3%) in estimated monthly PM_2.5 concentrations from 2019 to 2020 for the periods from March 11-April 10 and April 11-May 10, respectively. The March time period corresponded to the most stringent COVID-19 related restrictions in this region. Significant decreases in PM_2.5 were also reported by state monitoring sites during March (p < 0.001 compared to the previous 5-year average). While we observed decreases in PM_2.5 concentrations across the valley in 2020, it is important to note that the PM_2.5 concentrations did not improve equally in all locations. We observed the greatest reductions at lower elevation, more urbanized areas, likely because of the already low levels of PM_2.5 at the higher elevation, more residential areas, which were generally below 2 μg/m³ in both 2019 and 2020. Although many of measurements during March and April were near or below the estimated detection limit of the low-cost PM sensors and the federal equivalent measurements, every low-cost sensor (51) showed a reduction in PM_2.5 concentration in March of 2020 compared to 2019. These results suggest that the air quality improvement seen after March 11, 2020 is due to quarantine measures reducing traffic and decreasing pollutant emissions in the region.

Hypereosinophilia and epigastralgia after visiting Tunisia: a rare differential diagnosis of helminthiases

Causes of hypereosinophilia among travelers returning from North Africa are dominated by helminth infections, especially when associated with gastrointestinal signs. Non-infectious causes must nonetheless be investigated after negative microbiological assessment and failure of a broad empiric antiparasite treatment. We report the case of a young man with epigastralgia and major weight loss since a stay in Tunisia. Empiric treatment with albendazole was not successful. Eosinophilic gastroenteritis was diagnosed and resolved under corticosteroid treatment.

Hospitalization of HIV positive patients: Significant demand affecting all hospital sectors

BACKGROUND

In a context of the evolution of severe morbidities in patients living with HIV (PLWH), the aim of this study was to describe reasons for hospitalization and the mode of care for the patients requiring hospitalization.

METHODS

All admissions (≥24h) of PLWH to 10 hospitals in the south of Paris (COREVIH Ile-de-France Sud) between 1/1/2011 and 12/31/2011 were identified. The hospital database and the file of patients followed in the HIV referral department of each hospital were matched. Detailed clinical and biological data were collected, by returning to the individual medical records, for a random sample (65% of hospitalized patients).

RESULTS

A total of 3013 hospitalizations (1489 patients) were recorded in 2011. The estimated rate of hospitalized patients was about 8% among the 10105 PLWH routinely managed in COREVIH Ile-de-France Sud in 2011. The majority (58.5%) of these hospitalizations occurred in a unit other than the HIV referral unit. Non-AIDS-defining infections were the main reason for admission (16.4%), followed by HIV-related diseases (15.6%), hepatic/gastrointestinal diseases (12.0%), and cardiovascular diseases (10.3%). The median length of stay was 5 days overall (IQR: 2-11), it was longer among patients admitted to a referral HIV care unit than to another ward. HIV infection had been diagnosed >10 years previously in 61.4% of these hospitalized patients. They often had associated comorbidities (coinfection HCV/HVB 40.5%, smoking 45.8%; hypertension 33.4%, dyslipidemia 28.8%, diabetes 14.8%). Subjects over 60 years old accounted for 15% of hospitalized patients, most of them were virologically controlled under HIV treatment, and cardiovascular diseases were their leading reason for admission.

CONCLUSION

Needs for hospitalization among PLWH remain important, with a wide variety in causes of admission, involving all hospital departments. It is essential to prevent comorbidities to reduce these hospitalizations, and to maintain a link between the management of PLWH, that becomes rightly, increasing ambulatory, and recourse to specialized inpatient services.

The French Infectious Diseases Society's readiness and response to epidemic or biological risk-the current situation following the Middle East respiratory syndrome coronavirus and Ebola virus disease alerts

CONTEXT

In 2012, the French Infectious Diseases Society (French acronym SPILF) initiated the "Coordination of epidemic and biological risk" (SPILF-COREB - Emergences [SCE]) group to support the readiness and response of healthcare workers (HCWs) to new alerts.

OBJECTIVE

To present the SCE group, its functioning, and the main support it provided for frontline HCWs.

METHODS

A multidisciplinary group of heads of infectious disease departments from reference hospitals was created to build a network of clinical expertise for care, training, and research in the field of epidemic and biological risk (EBR). The network developed a set of standardized operational procedures (SOPs) to guide interventions to manage EBR-suspect patients.

RESULTS

A working group created the SOP aimed at frontline HCWs taking care of patients. Priority was given to the development of a generic procedure, which was then adapted according to the current alert. Five key steps were identified and hierarchized: detecting, protecting, caring for, alerting, and referring the EBR patient. The interaction between clinicians and those responsible for the protection of the community was crucial. The SOPs validated by the SPILF and its affiliates were disseminated to a wide range of key stakeholders through various media including workshops and the SPILF's website.

CONCLUSION

SPILF can easily adapt and timely mobilize the EBR expertise in case of an alert. The present work suggests that sharing and discussing this experience, initiated at the European level, can generate a new collective expertise and needs to be further developed and strengthened.

Severe infectious mononucleosis in immunocompetent adults

OBJECTIVES

To determine the risk factors for severe infectious mononucleosis (IM) occurrence in immunocompetent adults.

METHODS

We performed a multicenter, retrospective case series including immunocompetent adults presenting with confirmed IM between 2001 and 2011. Severe presentations were compared with uncomplicated presentations using Stata^® 9 software. The significance level was set at 5%.

RESULTS

In univariate analysis, age over 30 years (n=13 or 41.9% vs. n=5 or 12.8%; P=0.006), prior use of non-steroidal anti-inflammatory drugs (NSAIDs) (n=7 or 87.5% vs. n=1 or 12.5%; P=0.009), and smoking (n=13 or 68.4% vs. n=6 or 31.6%; P=0.013) were associated with severe IM onset. In multivariate analysis, only age over 30 years (OR=3.55; P=0.05) and prior use of NSAIDs (OR=15; P=0.05) remained associated with severe IM onset, without reaching significance level (P=0.05).

CONCLUSION

Our study confirmed that age over 30 years is a risk factor for severe IM onset. Prior use of NSAIDs also seems to be correlated with severe presentations. This new data needs to be confirmed in a prospective study.

[Anti-pneumococcal vaccine coverage for hospitalized risk patients: Assessment and suggestions for improvements]

Streptococcus pneumoniae can cause invasive infections. Incidence and severity are linked to patients' risk factors. Due to the resistance to leading antibiotics, the anti-pneumococcal vaccination has become a major public health issue. The purpose of this survey was to evaluate the anti-pneumococcal vaccine coverage in a population of adults with risk factors. This was a prospective study that included patients with at least one recommendation for pneumococcal vaccination as indicated by the Weekly Epidemiological Bulletin (BEH), to which three further US recommendations were added (diabetes, obesity and age>65years). One hundred and thirty-four patients with an average age of 70 years were included. The physician could only confirm 68 % of the patients' vaccination status. Vaccination coverage as recommended by the BEH board was 30 % (n=54). All HIV patients were vaccinated (n=2) and the vaccination coverage was 75 % (n=8) for patients treated for autoimmune diseases and only 10 % (n=20) for patients treated with chemotherapy. Patients with no vaccination didn't know the existence of the vaccine or didn't know that vaccination was recommended to them. This study has highlighted a deficit in pneumococcal vaccination coverage and a high level of ignorance of the existence of recommended vaccination. In addition to awareness campaign for patients and caregiver training, the expansion of the vaccine e-book utilization could improve the vaccination status.

[Acute pericarditis and tamponade: An unusual revelation of a visceral tuberculosis]

Tuberculosis is a common pulmonary disease, which is still endemic in disadvantaged communities. Pericarditis is a rare but very lethal visceral localization. The authors report the case of a 58-year-old man, without neither medical history nor social risk, who presented a cardiac tamponade as the first and atypic manifestation of a visceral tuberculosis.

Epithelial-specific A2B adenosine receptor signaling protects the colonic epithelial barrier during acute colitis

Central to inflammatory bowel disease (IBD) pathogenesis is loss of mucosal barrier function. Emerging evidence implicates extracellular adenosine signaling in attenuating mucosal inflammation. We hypothesized that adenosine-mediated protection from intestinal barrier dysfunction involves tissue-specific signaling through the A2B adenosine receptor (Adora2b) at the intestinal mucosal surface. To address this hypothesis, we combined pharmacologic studies and studies in mice with global or tissue-specific deletion of the Adora2b receptor. Adora2b(-/-) mice experienced a significantly heightened severity of colitis, associated with a more acute onset of disease and loss of intestinal epithelial barrier function. Comparison of mice with Adora2b deletion on vascular endothelial cells (Adora2b(fl/fl)VeCadCre(+)) or intestinal epithelia (Adora2b(fl/fl)VillinCre(+)) revealed a selective role for epithelial Adora2b signaling in attenuating colonic inflammation. In vitro studies with Adora2b knockdown in intestinal epithelial cultures or pharmacologic studies highlighted Adora2b-driven phosphorylation of vasodilator-stimulated phosphoprotein (VASP) as a specific barrier repair response. Similarly, in vivo studies in genetic mouse models or treatment studies with an Adora2b agonist (BAY 60-6583) recapitulate these findings. Taken together, our results suggest that intestinal epithelial Adora2b signaling provides protection during intestinal inflammation via enhancing mucosal barrier responses.

[A French soldier returns from the Central Africa Republic with hepatitis A: Vaccination failure is possible!]

In stays in tropical countries, the French military, and travelers in general, are exposed to diseases transmitted by the fecal-oral route, some of which are vaccine-preventable. Here we report a 42-yer-old soldier with hepatitis A, which first appeared on his return from a military operation in the Central African Republic. Despite its excellent immunogenicity and a duration of seroprotection extending beyond 20 years in the vast majority of cases, the hepatitis A vaccine can fail. This reminds us of the importance of combining vaccine and non-vaccine prevention in tropical countries, especially in precarious living conditions.

[History of malaria control in the French armed forces: from Algeria to the Macedonian front during the first World War]

The French joint military health corps has long experience in malaria control. Many military physicians played an essential role in the 19th century: Maillot revolutionized malaria treatment by using quinine during the conquest of Algeria, and Laveran discovered the causal parasite (the genus Plasmodium) there. This experience continued under the direction of Laveran and the Sergent brothers on the eastern front in Greek Macedonia during World War I. The vast coordinated control plan established on this front from 1917 delivered the French infantrymen from malaria and led to victory over the Bulgarian forces, which capitulated in September 1918.

Prevention of infectious diseases during military deployments: a review of the French armed forces strategy

Military personnel in operations have always paid a high toll to infections. In the 21st century some of these diseases still cause outbreaks with significant morbidity and impact on deployments. The new configuration of the French Armed Forces requires the permanent preparedness of deployable units. During deployments, soldiers are at least exposed to the infectious diseases that are observed in travellers, but with a potentially severe impact for the combatting strengths and a risk for cancelation or failure of the operational durability. The most common disabling infections during military deployments are faeco-oral transmitted diseases including diarrhoea. Preventing infectious diseases during deployments is of great concern and the French medical service has established a strategy based on different components; risk assessment and preparation, immunizations, protective measures and chemoprophylaxis, health education, health surveillance, outbreak investigations and medical tracking. In this review, the authors present the context of deployment of the French Armed Forces, the main health risks they are exposed to and develop the key points of the force health protection strategy, focused on infections related to military deployments.

Malaria control strategies in French armed forces

Each year, 40,000 French soldiers deploy or travel through malaria-endemic areas. Despite the effective control measures that were successively implemented, malaria remains a public health concern in French armed forces with several important outbreaks and one lethal case every two years. This article describes the malaria control strategy in French armed forces which is based on three combined strategies: i) Anopheles vector control to prevent infection with the implementation of personal protection against vectors (PPAV) adapted to the field living conditions of the troops. ii) Chemoprophylaxis (CP) to prevent the disease based on prescription of effective and well tolerated doxycycline. iii) Management of cases through early diagnosis and appropriate treatment to prevent death. In isolated conditions in endemic areas, rapid diagnosis tests (RDT) are used as first-line tests by military doctors. Treatment of uncomplicated Plasmodium falciparum (P. falciparum) malaria is based either on the piperaquine tetraphosphate-dihydroartemisinin association since 2013, or on the atovaquone-proguanil association. First-line treatment of severe P. falciparum malaria is based on IV artesunate. These measures are associated with constant education of the military, epidemiological surveillance of malaria cases and monitoring of parasite chemosensitivity.

Faecal carriage of extended-spectrum β-lactamase-producing enterobacteria among soldiers at admission in a French military hospital after aeromedical evacuation from overseas

The aim of this study was to assess the faecal carriage of carbapenemase-producing enterobacteria (CPE) and extended-spectrum β-lactamase (ESBL)-producing enterobacteria among soldiers at admission in a French military hospital after aeromedical evacuation from overseas. During a period of 1 year, 83 rectal swabs collected in French soldiers at admission were screened for multidrug-resistant enterobacteria with a chromogenic medium. ESBL detection was performed with the double-disc synergy test in the absence or presence of cloxacillin. The genotypic characterisation of resistance mechanisms, sequence typing and phylotyping was performed by polymerase chain reaction (PCR) and sequencing with bacterial DNA extracted from isolates. No CPE was detected. Eleven ESBL Escherichia coli isolates belonging to four phylogenetic groups were detected, including ten CTX-M-15 and one CTX-M-14. The overall gut colonisation with ESBL-producing bacteria (13.25 %) was 6-fold higher than that reported in soldiers in the suburbs of Paris in 2009. ESBL faecal carriage was particularly high (34.48 %) in soldiers repatriated from Afghanistan (risk ratio = 18.62; p = 0.0001). This study highlights the importance of systematic additional contact precautions and CPE/ESBL screening in soldiers repatriated from overseas in French hospitals.

Emergence of Plasmodium ovale malaria among the French Armed Forces in the Republic of Ivory Coast: 20 years of clinical and biological experience

BACKGROUND

French military surveillance identified an increase in Plasmodium ovale attacks among soldiers in Ivory Coast. This emergence and the low sensitivity of biological tests raise the question of a possible role of P. ovale variant species.

METHODS

Epidemiological data about P. ovale attacks from 1993 to 2012 were studied; the species diagnosis was based on a thin blood smear and/or a quick diagnostic test. Clinical and biological features in soldiers hospitalized in 2 French military hospitals were also reviewed. Malaria polymerase chain reaction followed by genotyping was performed when available.

RESULTS

French military physicians declared 328 P. ovale attacks over the 20-year study. A peak of incidence occurred in 2005. Among patients with positive blood smears, the quick diagnostic test was positive in 33 of 101 tests performed. The hospital study showed that symptoms and biological changes were not specific, which made diagnosis challenging: fever, anemia, and thrombocytopenia were not present in 20%, 71%, and 23% of the 45 confirmed cases, respectively. It was possible to perform molecular investigations on 19 clinical isolates: 18 were classic haplotypes with additional polymorphism and 1 was variant.

CONCLUSIONS

This emergence of P. ovale malaria enabled a good description to be made in nonimmune patients. The lack of sensitivity of both clinical features and quick diagnostic tests suggests an underestimation. Reasons for this outbreak are especially intense exposure to the vectors and the insufficient efficacy of doxycycline against P. ovale. The polymorphism of classic haplotypes of P. ovale rather than variant forms could be involved.

Cannabis use and cognitive functions in at-risk mental state and first episode psychosis

BACKGROUND

Meta-analyses suggest that schizophrenia patients with a history of cannabis use have less impaired cognitive functioning compared to patients without cannabis use.

AIMS

The objective of this study was to assess the association between recency and frequency of cannabis use and cognitive functioning in at-risk mental state for psychosis (ARMS) and first episode psychosis (FEP) individuals.

METHODS

One hundred thirty-six participants completed a cognitive test battery and were assessed for current and past cannabis use. Analyses of covariance models were applied to evaluate the main effects of cannabis use and patient group (ARMS vs. FEP) as well as their interactions on cognitive functioning.

RESULTS

No differences were observed in cognitive performance between current, former, and never users, and there were no significant interactions between cannabis use and patient group. Furthermore, within the group of current cannabis users, the frequency of cannabis use was not significantly associated with cognitive functioning.

CONCLUSION

The results of the present study do not support the notion that FEP patients and ARMS individuals with a history of cannabis use have less impaired cognitive functioning compared to those without cannabis use.

Aortic thrombus and multiple embolisms during a Mycoplasma pneumoniae infection

We report the case of a patient who presented with a thrombus of the aortic arch complicated with splenic, renal and peroneal artery embolisms, associated with transient lupus anticoagulant, during a Mycoplasma pneumoniae infection. The outcome was good under antibiotic and anticoagulant treatment. We also review the medical literature on M. pneumoniae-related thromboses.

[Prediction of psychosis by stepwise multilevel assessment--the Basel FePsy (Early Recognition of Psychosis)-Project]

BACKGROUND

We have conducted various studies in Basel with the aim of improving the methods for the early detection of psychosis (Früherkennung von Psychosen, FePsy).

METHODS

From 1.3.2000 to 29.2.2004 234 individuals were screened using the Basel Screening Instrument for Psychosis (BSIP). 106 patients were identified as at risk for psychosis; out of these 53 remained in follow-up for up to 7 years (mean 5.4 years). The assessments were done with a specifically developed instrument for history taking, various scales for the psychopathology, assessments of neuropsychology and fine motor functioning, clinical and quantitative EEG, MRI of the brain, laboratory etc.

RESULTS

Based on the BSIP alone, a relatively reliable prediction was possible: 21 (39.6%) of the individuals identified as at risk developed psychosis within the follow-up time. Post-hoc prediction could be improved to 81% by weighting psychopathology and including neuropsychology. Including the other domains obviously allows further improvements of prediction.

CONCLUSIONS

The risk for psychosis should be assessed in a stepwise procedure. In a first step, a clinically oriented screening should be conducted. If an at-risk status is found, further assessments in various domains should be done in a specialised centre.

[Assessment of vaccination coverage among travelers to areas where yellow fever is endemic (Senegal)]

This prospective survey, conducted at the Dakar airport from August 18, 2011, to May 8, 2012, asked a sample of travelers living in France and returning there after a stay in Senegal to complete a questionnaire. The aim of the study was to assess the determinants of vaccination coverage against yellow fever. The study included 10 298 travelers, with a median age of 48 years (interquartile range: 27-58); 52% were tourists, and 22% were traveling for business purposes. The measured level of anti-yellow fever vaccination coverage was 39.3%. Vaccination coverage was influenced by the travelers' level of knowledge and their perception of the risk.