Bioaugmentation of a rotating biological contactor for degradation of 2-fluorophenol

The performance of a laboratory scale rotating biological contactor (RBC) towards shock loadings of 2-fluorophenol (2-FP) was investigated. During a period of ca. 2 months organic shock loadings of 25 mg L?1 of 2-FP were applied to the RBC. As no biodegradation of 2-FP was observed, bioaugmentation of the RBC with a 2-FP degrading strain was carried out and, along ca. 6 months, organic shock loadings within a range of 25-200 mg L?1 of 2-FP were applied. Complete biodegradation of 50 mg L?1 of 2-FP was observed during operation of the reactor. The RBC showed to be robust towards starvation periods, as after ca. 1month of non-supply of the target compound, the reactor resumed 2-FP degradation. The inoculated strain was retained within the biofilm in the disks, as the 2-FP degrading strain was recovered from the biofilm by the end of the experiment, thus bioaugmentation was successfully achieved.     

Universal vaccine based on ectodomain of matrix protein 2 of influenza A: Fc receptors and alveolar macrophages mediate protection

The ectodomain of matrix protein 2 (M2e) of influenza A virus is an attractive target for a universal influenza A vaccine: the M2e sequence is highly conserved across influenza virus subtypes, and induced humoral anti-M2e immunity protects against a lethal influenza virus challenge in animal models. Clinical phase I studies with M2e vaccine candidates have been completed. However, the in vivo mechanism of immune protection induced by M2e-carrier vaccination is unclear. Using passive immunization experiments in wild-type, FcRγ(-/-), FcγRI(-/-), FcγRIII(-/-), and (FcγRI, FcγRIII)(-/-) mice, we report in this study that Fc receptors are essential for anti-M2e IgG-mediated immune protection. M2e-specific IgG1 isotype Abs are shown to require functional FcγRIII for in vivo immune protection but other anti-M2e IgG isotypes can rescue FcγRIII(-/-) mice from a lethal challenge. Using a conditional cell depletion protocol, we also demonstrate that alveolar macrophages (AM) play a crucial role in humoral M2e-specific immune protection. Additionally, we show that adoptive transfer of wild-type AM into (FcγRI, FcγRIII)(-/-) mice restores protection by passively transferred anti-M2e IgG. We conclude that AM and Fc receptor-dependent elimination of influenza A virus-infected cells are essential for protection by anti-M2e IgG.     

Competition between strains of Borrelia afzelii in the host tissues and consequences for transmission to ticks

Pathogen species often consist of genetically distinct strains, which can establish mixed infections or coinfections in the host. In coinfections, interactions between pathogen strains can have important consequences for their transmission success. We used the tick-borne bacterium Borrelia afzelii, which is the most common cause of Lyme disease in Europe, as a model multi-strain pathogen to investigate the relationship between coinfection, competition between strains, and strain-specific transmission success. Mus musculus mice were infected with one or two strains of B. afzelii, strain transmission success was measured by feeding ticks on mice, and the distribution of each strain in six different mouse organs and the ticks was measured using qPCR. Coinfection and competition reduced the tissue infection prevalence of both strains and changed their bacterial abundance in some tissues. Coinfection and competition also reduced the transmission success of the B. afzelii strains from the infected hosts to feeding ticks. The ability of the B. afzelii strains to establish infection in the host tissues was strongly correlated with their transmission success to the tick vector. Our study demonstrates that coinfection and competition between pathogen strains inside the host tissues can have major consequences for their transmission success.Subject terms: Microbial ecology, Bacteria     

Hypertensive Disorders of Pregnancy: A Systematic Review of International Clinical Practice Guidelines

Background

Clinical practice guidelines (CPGs) are developed to assist health care providers in decision-making. We systematically reviewed existing CPGs on the HDPs (hypertensive disorders of pregnancy) to inform clinical practice.

Methodology & Principal Findings

MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, Cochrane Methodology Register, Health Technology Assessments, and Database of Abstracts of Reviews of Effects (Ovid interface), Grey Matters, Google Scholar, and personal records were searched for CPGs on the HDPs (Jan/03 to Nov/13) in English, French, Dutch, or German. Of 13 CPGs identified, three were multinational and three developed for community/midwifery use. Length varied from 3–1188 pages and three guidelines did not formulate recommendations. Eight different grading systems were identified for assessing evidence quality and recommendation strength. No guideline scored ≧80% on every domain of the AGREE II, a tool for assessing guideline methodological quality; two CPGs did so for 5/6 domains. Consistency was seen for (i) definitions of hypertension, proteinuria, chronic and gestational hypertension; (ii) pre-eclampsia prevention for women at increased risk: calcium when intake is low and low-dose aspirin, but not vitamins C and E or diuretics; (iii) antihypertensive treatment of severe hypertension; (iv) MgSO4 for eclampsia and severe pre-eclampsia; (v) antenatal corticosteroids at <34 wks when delivery is probable within 7 days; (vi) delivery for women with severe pre-eclampsia pre-viability or pre-eclampsia at term; and (vii) active management of the third stage of labour with oxytocin. Notable inconsistencies were in: (i) definitions of pre-eclampsia and severe pre-eclampsia; (ii) target BP for non-severe hypertension; (iii) timing of delivery for women with pre-eclampsia and severe pre-eclampsia; (iv) MgSO4 for non-severe pre-eclampsia, and (v) postpartum maternal monitoring.

Conclusions

Existing international HDP CPGs have areas of consistency with which clinicians and researchers can work to develop auditable standards, and areas of inconsistency that should be addressed by future research.     

Needs Assessment for Performance Improvement of Personnel in Charge of Epidemiological Surveillance in Morocco

Background

In line with the International Health Regulations (IHR 2005), the Morocco health surveillance system has been reinforced via infrastructure strengthening and decentralization in its regions. To plan for personnel capacity reinforcement actions, a national workforce needs assessment was conducted by the National Epidemiological Surveillance Service and the World Health Organization.

Methods

The assessment used an ad-hoc method comprising two stages: (1) A survey via a standardized electronic questionnaire, administered to all staff in regional and provincial surveillance teams. Data collected included demographics, basic qualification, complementary training, perceived training needs, and preferred training modalities. Individuals were asked to grade, on a nine-point scale, their perception of importance of a given list of tasks and of their capacity to perform them. The gap between perceptions was quantified and described. (2) Field visits to national, regional and provincial sites for direct observation and opinion gathering on broader issues such as motivators, barriers, and training needs from the local perspective.

Results

Questionnaire respondents were 122/158 agents at 78 surveillance units countrywide. Mean age was 43.6 years and job longevity 5.7 years. Only 53% (65/122) had epidemiology training, posted in 62% (48/78) of the structures. Self-assessed capacity varied by basic qualification and by structure level (regional vs. provincial). The gap between the importance granted to a task and the perceived capacity to perform it was sizable, showing an uneven distribution across competency domains, regions, surveillance level and staff''s basic qualification. From the opinions gathered, a problem of staff demotivation and high turnover emerged clearly.

Conclusions

Our method was successful in revealing specific details of the training needs countrywide. A national strategy is needed to ensure rational planning of training, personnel motivation and long-term sustainability. In terms of training, an innovative program should target the specific needs per group and per region.     

Arts and Ageing; Life Expectancy of Historical Artists in the Low Countries

Practising arts has been linked to lowering stress, anxiety and blood pressure. These mechanisms are all known to affect the ageing process. Therefore, we examine the relation between long-term involvement in arts and life expectancy at age 50 (LE50), in a cohort of 12,159 male acoustic, literary and visual artists, who were born between 1700 and 1899 in the Low Countries. We compared the life expectancy at age 50 of the various artists with the elite and middle class of that time. In the birth cohorts before 1850, acoustic (LE50:14.5–19.5) and literary artists (LE50:17.8–20.8) had a similar life expectancy at age 50 compared to the elite (LE50:18.0–19.0). Only visual artists (LE50:15.5–17.1) had a lower life expectancy at age 50 compared to the elite at that time. For the most recent birth cohorts from 1850 through 1899, the comparison between artists and the elite reversed and acoustic and literary artist had a lower life expectancy at age 50, while visual artists enjoyed a similar life expectancy at age 50. Although artists belonged to the middle socioeconomic class and lived predominantly in urban areas with poor living conditions, they had a life expectancy similar to the elite population. This is in line with observed favourable effects of practicing arts on health in the short-term. From our historical analysis, we hypothesize several mechanisms through which artistic creativity could influence the ageing process and life expectancy. These hypotheses, however, should be formally tested before any definite conclusions on effects of arts on ageing can be drawn.     

More than black and white: differences in predictors of obesity among Native Hawaiian/Pacific Islanders and European Americans

Although Native Hawaiians and Pacific Islanders exhibit the highest rates of obesity and associated chronic diseases of any racial/ethnic group, they remain vastly underrepresented in health research. In a cross-sectional survey of college students (N = 402) we examined BMI and health outcomes in an ethno-racially diverse rural sample of Native Hawaiian/Pacific Islanders (25.1%), Asian Americans (39.8%), and European Americans (35.1%). Measures assessed BMI, health status, health behaviors, frequency of exercise, and symptoms of psychiatric disorders (i.e., depression, anxiety, posttraumatic stress, and substance abuse and dependence). Regression analyses revealed that an overall model of five predictors (gender, race, regular exercise, difficulty sleeping, and anxiety) was significantly associated with obesity (P < 0.001) and correctly classified 84.2% of cases. A 30.7% of Native Hawaiians/Pacific Islanders were obese as compared with 9.2% of European Americans and 10.6% of Asian Americans. These findings suggest that Native Hawaiian/ Pacific Islanders are at high risk for obesity and associated medical comorbidities, but that regular physical activity may ameliorate this risk. Further, these results support the consideration of Native Hawaiians/Pacific Islanders as a distinct racial/ethnic subgroup separate from other Asian populations.     

Discovering New Bioactive Neuropeptides in the Striatum Secretome Using in Vivo Microdialysis and Versatile Proteomics

The striatum, a major component of the brain basal nuclei, is central for planning and executing voluntary movements and undergoes lesions in neurodegenerative disorders such as Huntington disease. To perform highly integrated tasks, the striatum relies on a complex network of communication within and between brain regions with a key role devoted to secreted molecules. To characterize the rat striatum secretome, we combined in vivo microdialysis together with proteomics analysis of trypsin digests and peptidomics studies of native fragments. This versatile approach, carried out using different microdialysis probes and mass spectrometer devices, allowed evidencing with high confidence the expression of 88 proteins and 100 processed peptides. Their secretory pathways were predicted by in silico analysis. Whereas high molecular weight proteins were mainly secreted by the classical mode (94%), low molecular weight proteins equally used classical and non-classical modes (53 and 47%, respectively). In addition, our results suggested alternative secretion mechanisms not predicted by bioinformatics tools. Based on spectrum counting, we performed a relative quantification of secreted proteins and peptides in both basal and neuronal depolarization conditions. This allowed detecting a series of neuropeptide precursors and a 6-fold increase for neurosecretory protein VGF and proenkephalin (PENK) levels. A focused investigation and a long peptide experiment led to the identification of new secreted non-opioid PENK peptides, referred to as PENK 114–133, PENK 239–260, and PENK 143–185. Moreover we showed that injecting synthetic PENK 114–133 and PENK 239–260 into the striatum robustly increased glutamate release in this region. Thus, the combination of microdialysis and versatile proteomics methods shed new light on the secreted protein repertoire and evidenced novel neuropeptide transmitters.In mammalian brain, the striatum plays a critical role for planning and executing voluntary movements and is also involved in cognitive processes (1). The striatum makes use of a complex network architecture connecting specialized anatomical structures to achieve these highly integrated tasks. It receives projections from primary sensory and motor cortices as well as motor thalamic nuclei and sends projections to downstream basal ganglia structures, thereby influencing the control of cortical and brainstem motor systems (2). In this context, communication within and between brain structures appears as a key element for brain functioning. For cell-to-cell communication, secreted proteins play a pivotal regulatory role. To enter the secretory pathway, it has been long assumed that an N-terminal signal peptide sequence is strictly required. However, recent studies have shown that endoplasmic reticulum- and Golgi-independent or non-classical mechanisms may be responsible for protein secretion (3). The extracellular medium is thus more complex than previously suspected, and its characterization has gained a special interest (4, 5). In silico analyses suggest that mature proteins secreted via classical and non-classical mechanisms share common physicochemical properties (6). In this respect, proteomics is a powerful approach for systematically analyzing proteins present in the extracellular medium (7–9). For neurochemical monitoring of the secretome within the brain, only a few tools provide an appropriate insight into its spatial and temporal dynamics. Microdialysis, in particular, has been shown to be a powerful tool for exploring the extracellular content of the brain in vivo (10–12) and for obtaining vital physiological information that cannot be gleaned from in vitro experiments. The combination of this sampling method with mass spectrometry facilitates investigation of the brain secretome in vivo. However, because of the low concentration of proteins in dialysate, which makes investigations challenging in terms of sensitivity, few studies have combined in vivo brain microdialysis and proteomics/peptidomics analysis (13–16).In this study, to investigate both proteins and peptides secreted in rat striatum, we performed mass spectrometry analysis of microdialysis fluids. Microdialysis of small and large proteins was carried out using various cutoff probes, and the samples were analyzed through proteomics and peptidomics approaches. In addition, we used spectrum counting (17, 18) to measure the relative abundance of secreted proteins and their processed peptides and to study the modulation of these abundances during neuronal depolarization. This approach allowed us to point out the secretion of new neuropeptides, including neurotransmitters.     

A Patchy Growth via Successive and Simultaneous Cambia: Key to Success of the Most Widespread Mangrove Species Avicennia marina?

BACKGROUND AND AIMS: Secondary growth via successive cambia has been intriguing researchers for decades. Insight into the mechanism of growth layer formation is, however, limited to the cellular level. The present study aims to clarify secondary growth via successive cambia in the mangrove species Avicennia marina on a macroscopic level, addressing the formation of the growth layer network as a whole. In addition, previously suggested effects of salinity on growth layer formation were reconsidered. METHODS: A 1-year cambial marking experiment was performed on 80 trees from eight sites in two mangrove forests in Kenya. Environmental (soil water salinity and nutrients, soil texture, inundation frequency) and tree characteristics (diameter, height, leaf area index) were recorded for each site. Both groups of variables were analysed in relation to annual number of growth layers, annual radial increment and average growth layer width of stem discs. KEY RESULTS: Between trees of the same site, the number of growth layers formed during the 1-year study period varied from only part of a growth layer up to four growth layers, and was highly correlated to the corresponding radial increment (0-5 mm year(-1)), even along the different sides of asymmetric stem discs. The radial increment was unrelated to salinity, but the growth layer width decreased with increasing salinity and decreasing tree height. CONCLUSIONS: A patchy growth mechanism was proposed, with an optimal growth at distinct moments in time at different positions around the stem circumference. This strategy creates the opportunity to form several growth layers simultaneously, as observed in 14 % of the studied trees, which may optimize tree growth under favourable conditions. Strong evidence was provided for a mainly endogenous trigger controlling cambium differentiation, with an additional influence of current environmental conditions in a trade-off between hydraulic efficiency and mechanical stability.     

Minimally invasive sampling to identify leprosy patients with a high bacterial burden in the Union of the Comoros

The World Health Organization (WHO) endorsed diagnosis of leprosy (also known as Hansen’s disease) entirely based on clinical cardinal signs, without microbiological confirmation, which may lead to late or misdiagnosis. The use of slit skin smears is variable, but lacks sensitivity. In 2017–2018 during the ComLep study, on the island of Anjouan (Union of the Comoros; High priority country according to WHO, 310 patients were diagnosed with leprosy (paucibacillary = 159; multibacillary = 151), of whom 263 were sampled for a skin biopsy and fingerstick blood, and 260 for a minimally-invasive nasal swab. In 74.5% of all skin biopsies and in 15.4% of all nasal swabs, M. leprae DNA was detected. In 63.1% of fingerstick blood samples, M. leprae specific antibodies were detected with the quantitative αPGL-I test. Results show a strong correlation of αPGL-I IgM levels in fingerstick blood and RLEP-qPCR positivity of nasal swabs, with the M. leprae bacterial load measured by RLEP-qPCR of skin biopsies. Patients with a high bacterial load (≥50,000 bacilli in a skin biopsy) can be identified with combination of counting lesions and the αPGL-I test. To our knowledge, this is the first study that compared αPGL-I IgM levels in fingerstick blood with the bacterial load determined by RLEP-qPCR in skin biopsies of leprosy patients. The demonstrated potential of minimally invasive sampling such as fingerstick blood samples to identify high bacterial load persons likely to be accountable for the ongoing transmission, merits further evaluation in follow-up studies.