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Japanese knotweed (Reynoutria japonica Houtt.) is an invasive Asian plant abundant along rivers in its introduced range. In riparian areas, floods and ice flows uproot the rhizomes, facilitating their dissemination downstream. Control of large, well-established R. japonica clones in riparian areas is difficult if the use of herbicides is prohibited. An alternative to controlling entrenched clones is the rapid detection and manual unearthing of rhizome fragments that have recently rooted after being deposited by floodwaters. We applied this strategy along a Canadian river where spring floods with abundant ice are recurrent. Two river stretches, with approximately 10 km of shoreline each, were selected for the fragment removal campaign. One of the stretches was heavily invaded by R. japonica, while the other was only sparsely invaded. In the heavily invaded stretch, 1,550 and 737 R. japonica rhizome fragments were unearthed in 2019 and 2020, respectively. Unearthed fragments had an average length of 27 to 32 cm. Only 21 fragments were found in the sparsely invaded stretch in 2020. Despite similar distances being surveyed, the detection and unearthing took 62% less time (overall) in the sparsely invaded than in the heavily invaded stretch. Along sparsely invaded riverbanks, a rapid response removal campaign for R. japonica cost, including transportation and labor, an estimated Can$142 (US$105) per aborted clone (i.e., fragment removed). A rapid response removal campaign is economically advantageous compared with the hypothetical eradication of large, well-established clones, but for it to be cost-effective, the time spent locating rhizome fragments must exceed the time spent unearthing them. The question is not whether rapid response unearthing is economically feasible—it is—but rather what invasion level renders the intervention practicable. In highly invaded river stretches generating thousands of fragments annually, finding and removing these fragments year after year would require a massive, unsustainable effort.

BACKGROUND Most very premature newborns (< 32 weeks of gestation) receive parenteral nutrition (PN) that is inherently contaminated with peroxides. Oxidative stress induced by PN is associated with bronchopulmonary dysplasia, a main pathological complication in these babies who have weak antioxidant capacity to detoxify peroxides because of their glutathione deficiency. In animals, glutathione supplementation of PN prevented oxidative stress and alveolar loss (the main characteristic of bronchopulmonary dysplasia). Of its two forms - disulfide (GSSG) and free thiol (GSH) - GSSG was used because of its better stability in PN. However, a 30% loss of GSSG in PN is observed. The potentially high therapeutic benefits of GSSG supplementation on the health of very premature babies makes the study of its stability highly important. MATERIALS AND METHODS GSSG was incubated in combination with the following components of PN: dextrose, multivitamins, Primene, Travasol, as well as with cysteine, cystine and peroxides for 24h. Total glutathione in these solutions was measured 0-24h after the addition of GSSG. RESULTS The combination of cysteine and multivitamins caused the maximum loss of glutathione. The stability of GSSG was not affected by multivitamins. The cysteine was responsible for about 20% of the loss of GSSG, in presence of multivitamins the loss reached more than 70%. Removing the cysteine prevented the degradation of glutathione. CONCLUSION GSSG reacts with cysteine to form cysteine-glutathione disulfide, another suitable glutathione substrate for preterm neonates. The study confirms that GSSG added to PN can potentially provide a precursor to de novo synthesis of glutathione in vivo. This article is protected by copyright. All rights reserved.

Non-disclosure of positive HIV status in population-based surveys causes underestimation of national HIV diagnosis and biases inferences about engagement in the care continuum. This study investigated individual and household factors associated with HIV non-disclosure to survey interviewers in Nigeria.Secondary analysis of a cross sectional population-based household HIV survey.We analyzed data from adults aged 15-64 years who tested positive for HIV and had antiretroviral drugs (ARVs) in their blood from a nationally representative HIV sero-survey conducted in Nigeria in 2018. We considered ARV use as a proxy for knowledge of HIV diagnosis; thus, respondents who self-reported to be unaware of their HIV status were classified as non-disclosers. We estimated the associations between non-disclosure and various sociodemographic, clinical, and household characteristics using weighted logistic regression.Among 1266 respondents living with HIV who were taking ARVs, 503 (40%) did not disclose their HIV status to interviewers. In multivariable statistical analyses, the adjusted odds of non-disclosure were highest among respondents aged 15-24 years, those with less than a primary school education, and those who were the only person living with HIV in their household.Non-disclosure of positive HIV status to survey personnel is common among adults who are receiving treatment in Nigeria. These findings highlight the importance of validating self-reported HIV status in surveys using biomarkers of ARV use. Meanwhile, it is crucial to improve disclosure by strengthening interview procedures and tailoring strategies towards groups that are disproportionately likely to underreport HIV diagnoses.

Transgender and gender-diverse communities in Zambia are highly vulnerable and experience healthcare differently than cisgender persons. The University of Maryland, Baltimore (UMB) supports projects in Zambia to improve HIV case-finding, linkage and antiretroviral treatment (ART) for Zambia's transgender community. We describe programme strategies and outcomes for HIV prevention, testing and ART linkage among transgender communities.UMB utilizes a differentiated service delivery model whereby community health workers (CHWs) recruited from key populations (KPs) reach community members through a peer-to-peer approach, with the support of local transgender civil society organizations (CSOs) and community gatekeepers. Peer CHWs are trained and certified as HIV testers and psychosocial counsellors to offer counselling with HIV testing and prevention services in identified safe spaces. HIV-negative people at risk of HIV infection are offered pre-exposure prophylaxis (PrEP), while those who test positive for HIV are linked to ART services. CHWs collect data using the standardized facility and community tools and a dedicated DHIS2 database system. We conducted a descriptive analysis examining HIV testing and prevention outcomes using proportions and comparisons by time period and geographic strata.From October 2020 to June 2021, across Eastern, Lusaka, Western and Southern Provinces, 1860 transgender persons were reached with HIV prevention messages and services. Of these, 424 (23%) were tested for HIV and 78 (18%) tested positive. Of the 346 HIV-negative persons, 268 (78%) eligible transgender individuals were initiated on PrEP. ART linkage was 97%, with 76 out of the 78 transgender individuals living with HIV initiating treatment. Programme strategies that supported testing and linkage included peer CHWs, social network strategy testing, same-day ART initiation and local KP CSO support. Challenges included non-transgender-friendly environments, stigma and discrimination, the high transiency of the transgender community and the non-availability of transgender-specific health services, such as hormonal therapy.Peer KP CHWs were able to reach many members of the transgender community, providing safe HIV testing, PrEP services and linkage to care. Focusing on community gatekeepers and CSOs to disburse health messages and employ welcoming strategies supported high linkage to both PrEP and ART for transgender people in Zambia.

We investigated factors associated with loss to follow-up (LTFU) in 24 urban health facilities in Nairobi, Kenya. We conducted a retrospective analysis of routinely collected data to assess factors associated with LTFU in the period October 1, 2016, to June 30, 2017. LTFU was defined as no antiretroviral therapy (ART) refill for ≥90 days and no documentation of transfer, death, or treatment cessation in the patient chart, and if no lapse of ≥90 days between ART refills, patients were considered retained in care. Multivariable logistic regression modeling was used to compute odds ratios and 95% confidence interval (CI) for LTFU. Our analysis included 633 individuals who were LTFU and 13,098 individuals retained in care. Most participants (69.6%) were women, and median age was 33.0 years (interquartile range, 27.2-38.3 years). Median ART duration was shorter among those LTFU (0.4 years) than retained patients (2.5 years

We present the longest tree-ring chronology to date in northeastern North America (2233 years; 227 BCE – 2005 CE), resulting from several research projects conducted at the subarctic treeline in no...

In premature infants, glutathione deficiency impairs the capacity to detoxify the peroxides resulting from O2 metabolism and those contaminating the parenteral nutrition (PN) leading to increased oxidative stress, which is a major contributor to bronchopulmonary dysplasia (BPD) development. In animals, the supplementation of PN with glutathione prevented the induction of pulmonary oxidative stress and hypoalveolarization (characteristic of BPD). Hypothesis: the dose of glutathione that corrects the plasma glutathione deficiency is sufficient to prevent oxidative stress and preserve pulmonary integrity. Three-day-old guinea pigs received a PN, supplemented or not with GSSG (up to 1300 µg/kg/d), the stable form of glutathione in PN. Animals with no handling other than being orally fed constituted the control group. After 4 days, lungs were removed to determine the GSH, GSSG, redox potential and the alveolarization index. Total plasma glutathione was quantified. The effective dose to improve pulmonary GSH and prevent the loss of alveoli was 330 µg/kg/d. A 750 µg/kg/d dose corrected the low-plasma glutathione, high-pulmonary GSSG and oxidized redox potential. Therefore, the results suggest that, in a clinical setting, the dose that improves low-plasma glutathione could be effective in preventing BPD development.

L’ objectif de cette étude était de caractériser les communautés forestières du parc national du Mont-Saint-Bruno. Plus particulièrement, nous voulions trouver les sites présentant un caractère unique quant à leur composition floristique et déterminer comment cette unicité était associée à diverses variables environnementales. Nous avons aussi évalué si certaines espèces étaient indicatrices de la présence de bordure. Pour ce faire, nous avons utilisé les données d’un inventaire floristique fait en 2013 comprenant 133 placettes d’ échantillonnage. Au total, 173 taxons ont été identifiés, y compris 21 d’origine exotique et 11 indigènes à statut précaire. Les espèces exotiques étaient en général peu abondantes et peu fréquentes. La richesse et la diversité floristiques étaient plus élevées dans les placettes situées dans les dépressions ou en bas de pente. Les communautés présentes dans 8 placettes se distinguaient significativement des autres par la présence d’espèces de milieux humides. Les espèces indicatrices des bordures étaient soit intolérantes à l’ombre, tolérantes au stress hydrique, ou rudérales. Cette étude montre que les communautés floristiques forestières du parc sont pauvres en espèces exotiques, que les sites plus humides se distinguent de la flore relativement homogène qui caractérise le parc et que les bordures ont un effet sur la composition des communautés végétales., This study aimed to characterize the forest communities of the national park of mont-Saint-Bruno (Québec, Canada). Specifically, it sought to identify sites with unique floristic compositions and to determine how this uniqueness was associated with various environmental variables. It also aimed to evaluate whether certain species were indicators of edge effects. This was done using data from plant surveys conducted in 133 plots in 2013. A total of 173 taxa were identified, including 21 exotic and 11 native at-risk species. Exotic species were generally low in abundance and frequency. Species richness and diversity were higher in plots located in depressions or at the bottom of slopes. Floristic communities in 8 plots were significantly different from the rest, due to the presence of wetland species. Edge indicator species were either shade-intolerant, tolerant to hydric stress, or ruderal. This study highlighted that the forest communities of the national park of mont-Saint-Bruno had few exotic species. It also showed that the vegetation of wetter sites differed from the otherwise homogenous flora in the park and that edges impacted plant community composition.

Extremely premature birth is associated with a permanent disruption of energy metabolism. The underlying mechanisms are poorly understood. The oxidative stress induced by parenteral nutrition (PN) during the first week of life is suspected to reprogram energy metabolism in the liver. Full-term male Hartley guinea pigs (to isolate PN from prematurity) receiving PN enriched or not with glutathione (to isolate PN effects from PN-induced oxidative stress effects) or an Oral Nutrition (ON) during the first week of life were used. At 1 week (neonatal) and 16 weeks (adult), measurements of liver glutathione (GSH and GSSG) and activities of three key enzymes of energy metabolism (glucokinase (GCK), phosphofructokinase (PFK), and acetyl-CoA carboxylase (ACC)) were performed. Differences between groups were reported ifp≤ 0.05 (Analysis of Variance). At 1 week, compared to ON, PN induced higher GSSG (oxidative stress), higher GCK activity, and lower PFK and ACC activity, the glutathione supplement prevented all PN effects. At 16 weeks, early PN induced lower GSSG (reductive stress) and lower GCK activity, which was prevented by added glutathione, and higher ACC activity independent of glutathione supplement. ACC was negatively associated (r2= 0.33) with GSSG. Increased nicotinamide adenine dinucleotide phosphate levels confirmed the glucose-6-phosphate accumulation at 1 week, whereas our protocol failed to document lipid accumulation at 16 weeks. In adult male guinea pigs, neonatal exposure to PN affected glutathione metabolism leading to reductive stress (lower GSSG) and an altered metabolic flow of glucose. Partial prevention with glutathione supplementation suggests that, in addition to peroxides, other factors of PN are involved.

The metabolism of DNA methylation is reported to be sensitive to oxidant molecules or oxidative stress. Hypothesis: early-life oxidative stress characterized by the redox potential of glutathione influences the DNA methylation level. The in vivo study aimed at the impact of modulating redox potential of glutathione on DNA methylation. Newborn guinea pigs received different nutritive modalities for 4 days: oral nutrition, parenteral nutrition including lipid emulsion Intralipid (PN-IL) or SMOFLipid (PN-SF), protected or not from ambient light. Livers were collected for biochemical determinations. Redox potential (p 0.42; p

Zambia has made tremendous progress towards HIV epidemic control; however, gaps remain among key populations (KPs), such as female sex workers (FSWs), men who have sex with men (MSM), people who inject drugs (PWID) and people in prisons and enclosed settings due to cultural, social and legal barriers. The University of Maryland, Baltimore Zambia Community HIV Epidemic Control for Key Populations (Z-CHECK) project aimed to improve HIV case-finding, linkage and treatment adherence at the community level for KPs in Zambia. We describe Z-CHECK strategies and examine HIV positivity yield and antiretroviral therapy (ART) linkage among KPs to inform ongoing programme improvement.Z-CHECK recruited, trained and deployed peer community health workers (CHWs) for KP groups, with ongoing mentorship in community engagement. CHWs offered HIV testing in safe spaces and escorted newly HIV-diagnosed clients for same-day ART initiation. Z-CHECK also reached out to KP community leaders and gatekeepers for KP mobilization and trained healthcare workers (HCWs) on KP services and sensitivity. We conducted a retrospective observational review of routinely collected aggregate data for KPs aged ≥15 years at high risk for HIV transmission across five districts in Zambia from January 2019 to December 2020.Z-CHECK provided HIV testing for 9211 KPs, of whom 2227 were HIV positive (positivity yield, 24%). Among these, 1901 (85%) were linked to ART; linkage for MSM, FSW, PWID and people in prisons and enclosed settings was 95%, 89%, 86% and 65%, respectively. Programme strategies that contributed to high positivity yield and linkage included the use of peer KP CHWs, social network testing strategies and opportunities for same-day ART initiation. Challenges to programme implementation included stigma and discrimination among HCWs, as well as KP CHW attrition, which may be explained by high mobility.Peer CHWs were highly effective at reaching KP communities, identifying persons living with HIV and linking them to care. Engaging KP community gatekeepers resulted in high diffusion of health messages and increased access to health resources. The mobility of CHWs and HCWs is a challenge for programme implementation. Innovative interventions are needed to support PWID and people in prisons and enclosed settings.

Contaminated beef is a known vehicle of Escherichia coli O157:H7 infection, although more attention is given to the control of E. coli O157:H7 in ground, rather than whole-cut, beef products. In September 2012, an investigation was initiated at an Alberta, Canada, beef plant after the detection of E. coli O157:H7 in two samples of trim cut from beef originating from this plant. Later in September 2012, Alberta Health Services identified five laboratory-confirmed infections of E. coli O157:H7, and case patients reported eating needle-tenderized beef steaks purchased at a store in Edmonton, Alberta, produced with beef from the Alberta plant. In total, 18 laboratory-confirmed illnesses in Canada in September and October 2012 were linked to beef from the Alberta plant, including the five individuals who ate needle-tenderized steaks purchased at the Edmonton store. A unique strain of E. coli O157:H7, defined by molecular subtyping and whole genome sequencing, was detected in clinical isolates, four samples of leftover beef from case patient homes, and eight samples of Alberta plant beef tested by industry and food safety partners. Investigators identified several deficiencies in the control of E. coli O157:H7 at the plant; in particular, the evaluation of, and response to, the detection of E. coli O157 in beef samples during routine testing were inadequate. To control the outbreak, 4,000 tons of beef products were recalled, making it the largest beef recall in Canadian history. This outbreak, in combination with similar outbreaks in the United States and research demonstrating that mechanical tenderization can transfer foodborne pathogens present on the surface into the interior of beef cuts, prompted amendments to Canada's Food and Drug Regulations requiring mechanically tenderized beef to be labeled as such and to provide safe cooking instructions to consumers. A detailed review of this event also led to recommendations and action to improve the safety of Canada's beef supply.

Premature neonates are submitted to an early-life oxidative stress from parenteral nutrition, which is vitamin C (VC) deficient and induces low endogenous levels of glutathione. The oxidative stress caused by these deficiencies may permanently affect liver glycolysis and lipogenesis. This study evaluates the short- and long-term effects of neonatal VC and cysteine deficient diets on redox and energy metabolism. Three-day-old Hartley guinea pigs from both sexes were given a regular or a deficient diet (VC, cysteine, or both) until week 1 of life. Half of the animals were sacrificed at this age, while the other half ate a complete diet until 12 weeks. Liver glutathione and the activity and protein levels of glucokinase, phosphofructokinase, and acetyl-CoA-carboxylase were measured. Statistics: factorial ANOVA (5% threshold). At 1 week, all deficient diets decreased glutathione and the protein levels of glucokinase and phosphofructokinase, while cysteine deficiency decreased acetyl-CoA-carboxylase levels. A similar enzyme level was observed in control animals at 12 weeks. At this age, VC deficiency decreased glutathione, while cysteine increased it. Acetyl-CoA-carboxylase protein levels were increased, which decreased its specific activity. Early-life VC and cysteine deficiencies induce neonatal oxidative stress and an adult-like metabolism, while predisposing to increased lipogenic rates during adulthood.

Most very premature newborns (< 32 weeks of gestation) receive parenteral nutrition (PN) that is inherently contaminated with peroxides. Oxidative stress induced by PN is associated with bronchopulmonary dysplasia, a main pathological complication in these babies who have weak antioxidant capacity to detoxify peroxides because of their glutathione deficiency. In animals, glutathione supplementation of PN prevented oxidative stress and alveolar loss (the main characteristic of bronchopulmonary dysplasia). Of its two forms - disulfide (GSSG) and free thiol (GSH) - GSSG was used because of its better stability in PN. However, a 30% loss of GSSG in PN is observed. The potentially high therapeutic benefits of GSSG supplementation on the health of very premature babies makes the study of its stability highly important. Thus, GSSG was incubated in combination with the following components of PN: dextrose, multivitamins, Primene, Travasol, as well as with cysteine, cystine and peroxides for 24h. Total glutathione in these solutions was measured 0-24h after the addition of GSSG. The combination of cysteine and multivitamins caused the maximum loss of glutathione. Removing the cysteine prevented the degradation of glutathione. GSSG reacts with cysteine to form cysteine-glutathione disulfide, another suitable glutathione substrate for preterm neonates.

This study aimed to identify an appropriate simple mathematical model to fit the number of coronavirus disease 2019 (COVID-19) cases at the national level for the early portion of the pandemic, before significant public health interventions could be enacted. The total number of cases for the COVID-19 epidemic over time in 28 countries was analysed and fit to several simple rate models. The resulting model parameters were used to extrapolate projections for more recent data. While the Gompertz growth model (mean R2 = 0.998) best fit the current data, uncertainties in the eventual case limit introduced significant model errors. However, the quadratic rate model (mean R2 = 0.992) fit the current data best for 25 (89%) countries as determined by R2 values of the remaining models. Projection to the future using the simple quadratic model accurately forecast the number of future total number of cases 50% of the time up to 10 days in advance. Extrapolation to the future with the simple exponential model significantly overpredicted the total number of future cases. These results demonstrate that accurate future predictions of the case load in a given country can be made using this very simple model.

There are very few studies on the spontaneous revegetation of cutover fens or bogs from which peat has been extracted to the minerotrophic layers. Most peatlands with fen-type residual peat have problems regenerating a plant cover satisfactorily from a restoration point of view. We nevertheless found a site (Moss Spur, Manitoba, Canada) presenting a substantial and diversified spontaneous plant cover. We estimated that the site would provide insights about natural revegetation processes operating in peatlands. Vegetation assemblages and environmental conditions were surveyed 19 years after extraction activities ceased. Moss Spur has densely revegetated (163 plant species, vegetation cover of 94%) with minimal human assistance. However, the composition of plant assemblages varies considerably across the site, depending on certain abiotic variables, particularly water pH, water table level, and the thickness of the residual peat layer. Moss Spur was remarkably wet considering the past peat extraction activities and the absence of active rewetting procedures. The high water table level may in part explain the successful revegetation. However, plant assemblages were not of equal quality from a restoration perspective. Some assemblages were highly diversified, and especially those dominated by Scirpus cyperinus, a species that should be further considered in peatland restoration projects to direct the recovery of the peatland towards a natural fen species composition.

Le myriophylle à épis (Myriophyllum spicatum) est une plante vasculaire exotique envahissante qui colonise les lacs et les rivières de l’Amérique du Nord depuis plusieurs décennies. Nous avons reconstitué la progression historique de son invasion au Québec à l’aide de spécimens d’herbier, de bases de données, de rapports, de journaux et de périodiques. L’aire de répartition de la plante s’est beaucoup étendue depuis son introduction à la fin des années 1950. L’espèce s’est d’abord disséminée le long du fleuve Saint-Laurent. Elle s’est ensuite propagée à l’intérieur des terres à partir des années 1970. En 2017, 14 des 17 régions administratives du Québec comptaient au moins une mention de myriophylle à épis. Cela représentait 132 lacs, 16 rivières et ruisseaux — y compris le fleuve Saint-Laurent et ses lacs fluviaux — et 4 autres plans d’eau, tels que des étangs ou des voies navigables artificielles. À lui seul, le fleuve Saint-Laurent représentait 24 % des 322 mentions. Les régions avec le plus grand nombre de mentions sont celles de la Montérégie, des Laurentides, de l’Estrie et de l’Outaouais. Bien que l’envahissement par le myriophylle à épis semble avoir progressé de manière importante ces dernières années, il est possible que l’augmentation du nombre d’observations soit davantage le reflet d’une préoccupation grandissante des acteurs du territoire par rapport à l’envahisseur que d’une accélération réelle de l’invasion., Eurasian watermilfoil (Myriophyllum spicatum) is an exotic invasive vascular plant that has been colonizing North American lakes and rivers for several decades. The present study reconstructed its spread in Québec (Canada) using herbarium specimens, database records, reports, and articles in newspapers and scientific journals. The distribution of this plant has greatly expanded since its introduction in the late 1950s. The species first spread along the St. Lawrence River, and then from the 1970s, it started to establish further inland. In 2017, 14 of the 17 administrative regions in the province had at least one record of Eurasian watermilfoil, with reports from 132 lakes, 16 rivers (including the St. Lawrence River and its fluvial lakes) and brooks, and 4 other waterbodies, such as ponds or artificial waterways. The St. Lawrence River alone accounted for 24 % of the 322 records. The highest number of observations were from the Montérégie, Laurentides, Estrie and Outaouais regions. Although the invasion by this species appears to have progressed significantly in recent years, the increased number of records may, in part, reflect the growing concern of regional stakeholders, rather than an actual spread of the plant.

Background Parenteral nutrition (PN) is associated with bronchopulmonary dysplasia in premature infants. In animals, PN leads to alveolar loss following stimulation of apoptosis by oxidative stress (oxidized redox potential). Peroxides and aldehydes generated in PN can induce hypo-alveolarization. The implication of peroxides, which is reduced by light protection, is demonstrated. The implication of aldehydes from omega-6 fatty acids oxidation is expected. The hypothesis is that composition and light exposure of PN influences bronchopulmonary dysplasia development. Since SMOFLipid (SMOF) contains a lower amount of omega-6 fatty acids than Intralipid (IL), the aim was to compare, the impacts of PN compounded with SMOF or IL, photo-protected or not, on alveolar development. Materials and methods Three-day-old Guinea pigs received PN, photo-protected or not, made with SMOF or IL through a jugular vein catheter. After 4 days, lungs were sampled for determinations of redox potential of glutathione, apoptosis (caspase-3, caspase-8, and caspase-9) and alveolarization index (histology: number of intercepts/mm). Results Compared with IL, SMOF induces a greater oxidation of redox potential (-200 ± 1 versus [vs] -205 ± 1 mV), apoptosis (caspase-3: 0.27 ± 0.04 vs 0.16 ± 0.02; caspase-9: 0.47 ± 0.03 vs 0.30 ± 0.03), and a lower alveolarization index (27.2 ± 0.8 vs 30.0 ± 0.9). Photo-protection prevented activation of caspase-9 and was statistically without effect on redox potential, caspase-3, and alveolarization index. Conclusion In our model, SMOF is pro-oxidant and induces hypo-alveolarization following exaggerated apoptosis. These results highlight the need for further studies before introducing SMOFLipid in standard neonatal care.

We experimentally tested the feasibility of a control campaign of purple jewelweed (Impatiens glandulifera), an exotic invasive species in Europe and North America. We evaluated the amount of time and money required to control the plant along riverbanks, with particular attention paid to the recovery of riparian vegetation following hand pulling and bagging. Work time was directly and significantly related to stem density and fresh biomass of the invader, but the relationship was stronger for density. Density and biomass were strongly reduced by the first hand-pulling operation from a mean of 45 to 2 stems m−2 and from a mean of 0.95 kg m−2 to nearly zero, a good performance but not enough to negate the need for a second hand pulling later in the summer. A single hand pulling significantly reduced the cover of purple jewelweed from to 30% to 7%. Riparian vegetation disturbed by the first hand pulling largely recovered during the following 30 d. Expressed over an area of 1 ha, the total amount of time required to control purple jewelweed is 1,400 work hours over 2 yr, or a minimum investment of Can$21,000 (US$17,000). Although controlling a well-established purple jewelweed population is expensive, to properly evaluate the benefits, we must also consider the costs of soil erosion caused by this species.

Choosing past and present-day indicators could strengthen the reference ecosystem used for ecological restoration projects. Based on the paleoecological analysis of four peat cores and the characterization of 13 contemporary natural sites, the reference ecosystem for minerotrophic peatlands in southeastern Canada is composed of two broad categories of plant assemblages described as tall-sedge and Sphagnum–Thuja/brown moss. In paleoecological peat profiles, tall-sedge communities were found at the transition between aquatic and terrestrial, and were associated with high graminoid production, riverine peatlands, and elevated water table in the present-day analyses. Sphagnum–Thuja communities resemble the present-day vegetation found in natural basin type peatlands. Except for Sphagnum warnstorfii Russ., these communities, with high taxonomical diversity, contain more generalist species from boreal peatland vegetation, such as Rhododendron groenlandicum (Oeder) Kron & Judd, Thuja occidentalis L., Linnaea borealis L., and Maianthemum trifolium L. They grow in dryer or shady habitats such as hummocks or forest understory. The importance of brown mosses was revealed by paleoecological analysis. Overall, findings from both approaches are complementary: paleoecological stratigraphy informs us about past ecosystem dynamics, while present-day inventories allow us to define current plant communities and their major environmental characteristics. The range of variability of vegetation and environmental variables found in these studies are essential tools for fen restoration projects.

Extremely preterm babies are exposed to various sources of injury during critical stages of development. The extremely preterm infant faces premature transition to ex utero physiology and undergoes adaptive mechanisms that may be deleterious in the long term because of permanent alterations in organ structure and function. Perinatal events can also directly cause structural injury. These disturbances induce morphologic and functional changes in their organ systems that might heighten their risks for later adult chronic diseases. This review examines the pathophysiology of programming of long-term health and diseases after preterm birth and associated perinatal risk factors.

I conducted an exhaustive literature review on Japanese knotweeds s.l. (including Reynoutria japonica, R. sachalinensis and R. ×bohemica), especially on the effects of these invasive plants on biodiversity and ecological processes or the chemical and physical characteristics of invaded habitats. A total of 44 studies have been published, the earliest in 2005, in peer-reviewed journals. Most studies were conducted in Europe, the others in the USA. Invasive knotweeds have major negative impacts on native plants, while the abundant litter produced and the deep rhizome system alter soil chemistry to the benefit of the invaders. However, the effects of knotweeds on other groups of species vary, with a combination of losers (soil bacteria, most arthropods and gastropods, some frogs and birds) and winners (most fungi, detritivorous arthropods, aquatic shredders, a few birds). This literature review highlights significant knowledge gaps of the effects of knotweeds on biodiversity (vertebrates) and ecological processes (ecohydrology). To what extent knotweed invasions have an impact on the population dynamics of native plants and animals on a regional to national scale remains to be verified. Although there is some evidence that knotweed invasions have negative effects on the environment, the research to date remains modest and a more extensive effort is needed to better define the environmental impacts of these plant invaders.

Preterm birth incurs an increased risk of early cardiovascular events and death. In the general population, cardiovascular risk factors cluster in the context of inflammation and oxidative stress. Whether this also occurs in young adults born preterm is unknown. We analyzed 101 healthy young adults (ages 18–29) born preterm (≤29 weeks of gestation) and 105 full-term controls, predominantly (90%) white. They underwent a comprehensive clinical and biological evaluation, including measurement of blood pressure, lung function (spirometry), glucose metabolism (fasting glucose, glycated hemoglobin, and oral glucose tolerance test), as well as biomarkers of inflammation and oxidative stress. Individuals born preterm were at higher risk than those born full-term of stage ≥1 hypertension (adjusted odds ratio, 2.91 [95% CI, 1.51–5.75]), glucose intolerance (adjusted odds ratio, 2.22 [95% CI, 1.13–4.48]), and airflow limitation (adjusted odds ratio, 3.47 [95% CI, 1.76–7.12]). Hypertension was strongly associated with adiposity and with glucose intolerance in participants born full-term but not in those born preterm. We did not find any group difference in levels of biomarkers of inflammation and oxidative stress. In individuals born preterm, inflammation, and oxidative stress were not related to hypertension or glucose intolerance but were associated with adiposity. In those born preterm, cardiovascular risk factors were not related to each other suggesting different pathophysiological pathways leading to the development of cardiovascular risk following preterm birth. Clinicians should consider screening for these abnormalities irrespectively of other risk factors in this at-risk population. Clinical Trial Registration URL: http://www.clinicaltrials.gov . Unique identifier: NCT03261609.

Introduction Current healthcare systems fail to provide adequate HIV services to men. In Zambia, 25% of adult men living with HIV were unaware of their HIV status in 2018, and 12% of those who were unaware of their HIV statu were not receiving antiretroviral therapy (ART) due to pervasive barriers to HIV testing services (HTS) and linkage to ART. To identify men and key and priority populations living with HIV in Zambia, and link them to care and treatment, we implemented the Community Impact to Reach Key and Underserved Individuals for Treatment and Support (CIRKUITS) project. We present HTS and ART linkage results from the first year of CIRKUITS. Methods CIRKUITS aimed to reach beneficiaries by training, mentoring, and deploying community health workers to provide index testing services and targeted community HTS. Community leaders and workplace supervisors were engaged to enable workplace HTS for men. To evaluate the effects of these interventions, we collected age‐ and sex‐disaggregated routinely collected programme data for the first 12 months of the project (October 2018 to September 2019) across 37 CIRKUITS‐supported facilities in three provinces. We performed descriptive statistics and estimated index cascades for indicators of interest, and used Chi square tests to compare indicators by age, sex, and district strata. Results Over 12 months, CIRKUITS tested 38,255 persons for HIV, identifying 10,974 (29%) new people living with HIV, of whom 10,239 (93%) were linked to ART. Among men, CIRKUITS tested 18,336 clients and identified 4458 (24%) as HIV positive, linked 4132 (93%) to ART. Men who tested HIV negative were referred to preventative services. Of the men found HIV positive, and 13.0% were aged 15 to 24 years, 60.3% were aged 25 to 39, 20.9% were aged 40 to 49 and 5.8% were ≥50 years old. Index testing services identified 2186 (49%) of HIV‐positive men, with a positivity yield of 40% and linkage of 88%. Targeted community testing modalities accounted for 2272 (51%) of HIV‐positive men identified, with positivity yield of 17% and linkage of 97%. Conclusions Index testing and targeted community‐based HTS are effective strategies to identify men living with HIV in Zambia. Index testing results in higher yield, but lower linkage and fewer absolute men identified compared to targeted community‐based HTS.

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Peroxides contaminating parenteral nutrition (PN) limit the use of methionine as a precursor of cysteine. Thus, PN causes a cysteine deficiency, characterized by low levels of glutathione, the main molecule used in peroxide detoxification, and limited growth in individuals receiving long-term PN compared to the average population. We hypothesize that glutathione supplementation in PN can be used as a pro-cysteine that improves glutathione levels and protein synthesis and reduces oxidative stress caused by PN. One-month-old guinea pigs (7&ndash, 8 per group) were used to compare glutathione-enriched to a non-enriched PN, animals on enteral nutrition were used as a reference. PN: Dextrose, amino acids (Primene), lipid emulsion (Intralipid), multivitamins, electrolytes, five-day infusion. Glutathione (GSH, GSSG, redox potential) and the incorporation of radioactive leucine into the protein fraction (protein synthesis index) were measured in the blood, lungs, liver, and gastrocnemius muscle. Data were analysed by ANOVA, p &lt, 0.05 was considered significant. The addition of glutathione to PN prevented the PN-induced oxidative stress in the lungs and muscles and supported protein synthesis in liver and muscles. The results potentially support the recommendation to add glutathione to the PN and demonstrate that glutathione could act as a biologically available cysteine precursor.

Herbarium specimens can be used to reconstruct spatiotemporal changes in plant morphology caused by environmental pressures. The reliability of herbarium-derived data requires evaluation, because specimen collection is subject to biases. We used herbarium and field data to investigate the impact of large herbivore browsing on the size of a forb. White trillium (Trillium grandiflorum (Michaux) Salisbury) was studied because the impacts of white-tailed deer (Odocoileus virginianus Zimmermann) browsing on this species are well-known. A total of 692 herbarium specimens collected in Quebec (Canada) were used to evaluate leaf area. Leaf area values of herbarium specimens were compared with those of modern (2013, 2014) specimens collected in sites either with >8 deer per square kilometre or without deer. Flowering individuals in modern sites with deer had a significantly lower leaf area than herbarium specimens and modern specimens collected in sites without deer. The distribution of white trillium individuals in deer sites was also skewed towards plants with a smaller leaf area. Herbarium specimens may offer unique and inexpensive data, compared with methods traditionally used to assess the impacts of herbivores on plants, such as exclosures or clipping experiments. Unfortunately, this rich data source is seriously jeopardized by the downtrend in specimen collecting.

OBJECTIVES: Human infection with Escherichia coli O157:H7/NM has historically been associated with consumption of undercooked ground beef. The purpose of this paper is to investigate the correlation of the decline in E. coli O157:H7/NM infections in Canada with the introduction of control efforts in ground beef by industry. METHODS: The human incidence of E. coli O157:H7/NM, prevalence in ground beef and interventions from 1996 to 2014 were analyzed. Pathogen prevalence data were obtained from federal government and industry surveillance and inspection/compliance programs. A survey of the largest ground beef producers in Canada was conducted to identify when interventions were implemented. RESULTS: The incidence of E. coli O157:H7/NM infections in Canada declined from ∼4 cases/100 000 to ∼1 case/100 000 from 2000 to 2010. Verotoxigenic Escherichia coli (VTEC) prevalence in ground beef sold at retail declined from about 30% around the year 2000 to

Hypothesis: Optimizing glutathione status in symptomatic COVID-19 patients may prevent the development of more severe aspects of the disease During the inflammatory phase in symptomatic COVID-19 patients the oxidant stress has the potential to be massive The observed cytokine storm is a source of free radicals that can cause a major oxidant stress, which in turn leads to a self-fueling vicious cycle of cytokine-mediated oxidant injury SARS-CoV-2 virus uses the angiotensin-converting enzyme 2 (ACE2) receptor to invade the cell ACE2 activation induces an antioxidant response by activating Nrf2 and inhibiting NFκB Nrf2 promotes production of glutathione that could reduce NFκB activation and consequently reduce generation of cytokines Could the glutathione status of individuals account for the unexplained variability in clinical presentations of COVID-19? Elderly subjects are the hardest hit by COVID-19 Beyond their comorbidities, they exhibit a slower protein metabolism explaining the lower level of plasma glutathione reported in this population Obesity is an aggravating factor observed in deaths occurring in elderly and younger COVID-19 patients Beyond the comorbidities such as diabetes, hypertension, cardiovascular diseases associated with obesity, the metabolic syndrome reported in these subjects is associated with lower glutathione levels and oxidant stress Optimizing glutathione levels should be considered in symptomatic subjects with proven COVID-19 Following the action of endogenous gamma-glutamyltranspeptidase, plasma glutathione is an efficient source of substrates for de novo tissue synthesis of glutathione The injection of glutathione might be contemplated in these patients Although injectable glutathione is not yet available on the market, N-acetylcysteine (NAC) could be considered It is an existing and approved form of bioavailable cysteine limiting substrate for glutathione synthesis In a recent review on NAC in COVID-19, the Center for Evidence Based Medicine (University of Oxford, UK) concluded that preclinical data suggest that NAC may have a purpose in viral respiratory infections doi: xxxxx

Oxidative stress-induced retinal pigment epithelial cell (RPE) dysfunction is a primary contributing factor to early dry age-related macular degeneration (AMD). Oxidative injury to the retina may promote extracellular vesicles (EVs) released from RPE. In this study, we investigated the effects of oxidative-induced RPE cell-derived microparticles (RMPs) on RPE cell functions. The oxidative stress induced more RMPs released from RPE cells in vitro and in vivo, and significant more RMPs were released from aged RPE cells than that from younger RPE cells. RMPs were taken up by RPE cells in a time-dependent manner; however, blockage of CD36 attenuated the uptake process. Furthermore, the decrease of RPE cell viability by RMPs treatment was associated with an increased expression of cyclin-dependent kinase inhibitors p15 and p21. RMPs enhanced senescence and interrupted phagocytic activity of RPE cells as well. The present study demonstrated that RMPs produce a strong effect of inducing RPE cell degeneration. This finding further supports the postulate that RMPs exacerbate oxidative stress damage to RPE cells, which may uncover a potentially relevant process in the genesis of dry AMD.

International audience; The spread of many invasive plants could be facilitated by their presence in urban areas that may act as dispersal centres and by climate warming. Cortaderia selloana, pampas grass, is native to South America and raises considerable concern worldwide as an introduction. We used Maxent niche modelling, based on occurrence records and on a set of simulated occurrence points with high probability of presence in urbanised areas in France, where the species was introduced and is still planted. We calibrated the model with current climate data coupled with several habitat variables and used it to predict range shifts of C. selloana under four climate change scenarios (RCP) for 2060. The results were consistent with the known ecology of the species and showed that the most important variables that explain the current distribution in the introduced area were mean annual minimum temperatures, sandy habitats, disturbed habitats and urbanised areas. While the species already occupies large areas along the western and Mediterranean coasts, the models predicted an expansion northward and inland to the east under future climates. The area of suitable habitats could increase by up to 69% under the RCP 8.5 climate scenario in 2060 and by 116% with the extra occurrences in urban/suburban areas. This latter scenario suggests that areas like public and private gardens or urban parks, where the species is currently cultivated, could contribute to increase the invasion risk under climate warming. The results provide predictions of potential environments for the species, which can be helpful for anticipating its spread.