Connectivity of stormwater ponds impacts Odonata abundance and species richness.

Context: The successful dispersal of an animal depends, partly, on landscape connectivity. Urbanization poses risks to dispersal activities by increasing hostile land cover types. Objectives: We investigated how connectivity of urban ponds impacted Odonata communities (dragonflies and damselflies), an order of semi-aquatic insects that actively disperse. Methods: We sampled 41 constructed stormwater ponds and 8 natural ponds in a metropolitan area. The effect of connectivity and the quantity of available adjacent habitats was tested at different scales for dragonflies (900 m) and damselflies (300 m), determined by a literature analysis, to account for differences in suborder dispersal capabilities. Results: Lower levels of connectivity and fewer nearest neighbours negatively impacted abundance, species richness, and composition of dragonflies (p values < 0.01, R2 = 0.18-0.70). Adult dragonfly abundance had a stronger positive relationship with connectivity than species richness. In particular, the abundance of adult dragonfly Leucorrhinia frigida, found almost exclusively at natural ponds, had a positive relationship with connectivity. Connectivity and the number of nearest neighbours had no significant impact on damselflies apart from a slight negative relationship between connectivity and species richness (p value = 0.02, R2 = 0.11). Natural ponds had significantly higher levels of connectivity when compared to stormwater ponds. Conclusions: Our results suggest that dragonflies are positively affected by increased connectivity in an urban landscape, with no benefit of connectivity to damselflies at the scale measured. We recommend intentional planning of urban stormwater pond networks, where individual ponds can act as stepping stones, incorporated with strategic inclusion of beneficial land cover types. Supplementary Information: The online version contains supplementary material available at 10.1007/s10980-024-01817-z.

Group-based exercice training programs for military members presenting musculoskeletal disorders - protocol for a pragmatic randomized controlled trial.

BACKGROUND: Musculoskeletal disorders are a leading cause of morbidity and the most prevalent source of disability among soldiers. Their high prevalence in armed forces and limited ressources have led to problems related to access to physical rehabilitation care. To increase access, supervised group-based exercise programs for the most prevalent musculoskeletal disorders (low back pain, patellofemoral pain, rotator cuff-related shoulder pain or lateral ankle sprain) have been developed at a Canadian Armed forces (CAF) base, but their effectiveness has not been evaluated. The primary objective of this randomized controlled trial is to evaluate the mid- and long-term effects of these group-based training programs on pain severity and functional limitations, in comparison with usual individual physiotherapy care. Secondary objectives include comparing both interventions in terms of health-related quality of life, pain-related fear, and patients' satisfaction. METHODS: One hundred and twenty soldiers with a new medical referral for physiotherapy services for one of the four targeted musculoskeletal disorders will be consecutively recruited. They will be randomly assigned to either group-based training program or usual individual physiotherapy care, and will take part in the assigned 12-week intervention. There will be four evaluation sessions over 26 weeks (baseline, week 6, 12 and 26). At each follow-up, functional limitations, pain severity, health-related quality of life and pain-related fears will be assessed. Patients satisfaction with treatment will also be evaluated at the end of the intervention period. Either two-way repeated measures ANOVA will be used to analyse and compare the effects of the interventions. DISCUSSION: This RCT will determine the effectiveness of group-based training programs compared to usual individual physiotherapy care. This new intervention model could represent an efficient, and more pro-active approach to manage a higher number of soldiers with musculoskeletal disorders. It could improve access to physical rehabilitation care and improve the health of soldiers. TRIAL REGISTRATION: ClinicalTrials.gov ( NCT05235152 ), February 11th 2022.

Considerations for upscaling individual effects of wind energy development towards population-level impacts on wildlife.

The expansion of wind energy poses challenges to policy- and decision-makers to address conflicts with wildlife. Conflicts are associated with impacts of existing and planned projects on wildlife, and associated difficulties of prediction where impacts are subject to considerable uncertainty. Many post-construction studies have demonstrated adverse effects on individuals of various bird and bat species. These effects may come in the form of collision-induced mortality or behavioral or physiological changes reducing the fitness of individuals exposed to wind energy facilities. Upscaling these individual effects to population impacts provides information on the true value of interest from a conservation point of view. This paper identifies methodological issues associated when moving from individual effects to population impacts in the context of wind energy. Distinct methodological approaches to predict population impacts are described using published case studies. The various choices of study design and metrics available to detect significant changes at the population level are further assessed based on these. Ways to derive impact thresholds relevant for decision-making are discussed in detail. Robust monitoring schemes and sophisticated modelling techniques may inevitably be unable to describe the whole complexity of wind and wildlife interactions and the natural variability of animal populations. Still, they will provide an improved understanding of the response of wildlife to wind energy and better-informed policies to support risk-based decision-making. Policies that support the use of adaptive management will promote assessments at the population level. Providing information to adequately balance the development of wind energy with the persistence of wildlife populations.

The nucleoside analog GS-441524 strongly inhibits feline infectious peritonitis (FIP) virus in tissue culture and experimental cat infection studies.

Feline infectious peritonitis (FIP) is a common and highly lethal coronavirus disease of domestic cats. Recent studies of diseases caused by several RNA viruses in people and other species indicate that antiviral therapy may be effective against FIP in cats. The small molecule nucleoside analog GS-441524 is a molecular precursor to a pharmacologically active nucleoside triphosphate molecule. These analogs act as an alternative substrate and RNA-chain terminator of viral RNA dependent RNA polymerase. We determined that GS-441524 was non-toxic in feline cells at concentrations as high as 100 uM and effectively inhibited FIPV replication in cultured CRFK cells and in naturally infected feline peritoneal macrophages at concentrations as low as 1 uM. We determined the pharmacokinetics of GS-441524 in cats in vivo and established a dosage that would sustain effective blood levels for 24 h. In an experimental FIPV infection of cats, GS-441524 treatment caused a rapid reversal of disease signs and return to normality with as little as two weeks of treatment in 10/10 cats and with no apparent toxicity.

The Interferon Type I/III Response to Respiratory Syncytial Virus Infection in Airway Epithelial Cells Can Be Attenuated or Amplified by Antiviral Treatment.

UNLABELLED: Human respiratory syncytial virus (RSV) is a single-stranded RNA virus that causes acute, and occasionally fatal, lower respiratory illness in young infants, the elderly, and immunocompromised patients. Therapeutic interventions able to cut short viral replication and quickly return the airways to normal function are needed. An understanding of antiviral activities and their effects on host defense mechanisms is important for the design of safe and effective therapy. We targeted functionally and temporally distinct steps within the viral life cycle using small-molecule RSV inhibitors and studied their antiviral activities and their effects on innate interferon responses of airway epithelial cells in vitro. Antivirals acting upstream of RSV polymerase activity (i.e., compounds targeting the fusion protein or the nucleoprotein) reduced viral load immediately postinfection and partially attenuated interferon responses. In contrast, antivirals directed to the RSV polymerase demonstrated activity throughout the viral replication cycle and specifically modulated the RIG-I/mitochondrial antiviral signaling protein (MAVS)/TBK1/IRF3/interferon-stimulated gene (ISG) axis, causing either an upregulation or a downregulation of interferon responses, depending on the mechanism of polymerase inhibition. Notably, polymerase inhibition leading to the accumulation of abortive RNA products correlated with the amplification of interferon-stimulated genes to up to 10 times above normal infection levels. Understanding how antiviral activities and their modulation of innate immunity may affect recovery from RSV infection will help guide the development of safe and effective therapies. IMPORTANCE: RSV circulates seasonally, causing acute lower respiratory disease. Therapeutic interventions with efficacy throughout the viral replication cycle, rapid viral clearance, and prevention of potentially harmful inflammatory responses are desirable. Compounds targeting the RSV polymerase inhibited virus replication late in the viral life cycle and, depending on the functional domain targeted, either attenuated or amplified RIG-I and downstream interferon pathways in infected cells. These data will help guide the development of safe and effective therapies by providing new molecular evidence that the mechanism of inhibition by an antiviral compound can directly impact innate antiviral immune responses in the airway epithelium.

Visceral fat enhances blood pressure reactivity to physical but not mental challenges in male adolescents.

BACKGROUND: Excess visceral fat is a major risk factor for hypertension. Enhanced blood pressure (BP) reactivity and delayed BP recovery from physical and mental challenges predict future hypertension. OBJECTIVES: Determine whether visceral fat is associated with higher BP reactivity and delayed BP recovery from physical and mental challenges during adolescence. METHODS: In a community-based sample of 283 male and 308 female adolescents, we measured visceral fat with magnetic resonance imaging, total body fat with bioimpedance, and beat-by-beat BP with a Finometer at rest and during physical (10-min standing) and mental (2-min math stress) challenges. RESULTS: Males vs. females showed greater BP reactivity and no differences in BP recovery from either type of challenges. Visceral fat was positively associated with BP reactivity to standing up only and in males only (+8.4 ± 3.6 mmHg per 1 log cm(3) of visceral fat, P = 0.008), and this association was independent of total body fat. No association was seen between visceral fat and BP recovery from either type of challenge in either sex. All these associations were independent of age, puberty stage, height and initial BP. CONCLUSIONS: Adolescent males vs. females demonstrate greater BP reactivity but similar BP recovery from physical and mental challenges. Excess visceral fat enhances BP reactivity to physical but not mental challenges in males only.

Opioid receptor mu 1 gene, fat intake and obesity in adolescence.

Dietary preference for fat may increase risk for obesity. It is a complex behavior regulated in part by the amygdala, a brain structure involved in reward processing and food behavior, and modulated by genetic factors. Here, we conducted a genome-wide association study (GWAS) to search for gene loci associated with dietary intake of fat, and we tested whether these loci are also associated with adiposity and amygdala volume. We studied 598 adolescents (12-18 years) recruited from the French-Canadian founder population and genotyped them with 530 011 single-nucleotide polymorphisms. Fat intake was assessed with a 24-hour food recall. Adiposity was examined with anthropometry and bioimpedance. Amygdala volume was measured by magnetic resonance imaging. GWAS identified a locus of fat intake in the µ-opioid receptor gene (OPRM1, rs2281617, P=5.2 × 10(-6)), which encodes a receptor expressed in the brain-reward system and shown previously to modulate fat preference in animals. The minor OPRM1 allele appeared to have a 'protective' effect: it was associated with lower fat intake (by 4%) and lower body-fat mass (by ∼2 kg, P=0.02). Consistent with the possible amygdala-mediated inhibition of fat preference, this allele was additionally associated with higher amygdala volume (by 69 mm(3), P=0.02) and, in the carriers of this allele, amygdala volume correlated inversely with fat intake (P=0.02). Finally, OPRM1 was associated with fat intake in an independent sample of 490 young adults. In summary, OPRM1 may modulate dietary intake of fat and hence risk for obesity, and this effect may be modulated by subtle variations in the amygdala volume.

Visceral fat is associated with lower executive functioning in adolescents.

BACKGROUND: Obesity, a major risk factor for cardiometabolic disease, is associated with lower cognitive performance from childhood to senescence, especially on tasks of executive function. In the cardiovascular domain, fat stored viscerally rather than elsewhere in the body carries particularly high risk. It is unknown whether this is also true in case of obesity-cognition relationships. The aim of this study was to assess the cross-sectional relationship between visceral fat (VF) and cognitive performance in a community sample of healthy adolescents. METHODS: In a community-based sample of 983 adolescents (12-18 years old, 480 males), VF was quantified using magnetic resonance imaging, total body fat was measured using a multifrequency bioimpedance, and cognitive performance was assessed using a battery of cognitive tests measuring executive function and memory. RESULTS: We found that larger volumes of VF were associated with lower performance on six measures of executive function (P=0.0001-0.02). We also found that the association of VF with executive function was moderated by sex for a subset of measures, such that relationship was present mainly in female subjects and not in male subjects (sex-by-VF interaction: P=0.001-0.04). These relationships were independent of the quantity of total body fat and a number of potential confounders, including age, puberty stage and household income. CONCLUSIONS: Our results suggest that the adverse association between obesity and executive function may be attributed to fat stored viscerally and not to fat stored elsewhere in the body. They also suggest that female subjects compared with male subjects may be more sensitive to the potentially detrimental effects of VF on cognition.

A decade of mammalian retinal stem cell research.

Ten years have now passed since the discovery of quiescent neural stem cells within the mammalian retina. Beside the fascinating aspect of stem cell biology in basic science, these cells have also offered hope for the treatment of incurable retinal diseases. The field has thus rapidly evolved, fluctuating between major advances and recurring doubts. In this review, we will retrace the efforts of scientists during this last decade to characterize these cells and to use them in regenerative medicine. We will also highlight advances made in animal models capable of stem cell-mediated retinal regeneration.

Clinical and genetic knowledge and attitudes of patients with myotonic dystrophy type 1.

AIMS: The goal was to assess clinical and genetic knowledge and attitudes in patients affected by myotonic dystrophy type 1 (DM1). METHODS: Two hundred patients with molecular confirmation of the diagnosis of DM1 completed a multi-choice questionnaire. DM1 patients' knowledge and views were compared to clinically normal DM1 noncarriers (n = 264) and controls (n = 1,474). RESULTS: Knowledge of the DM1 mode of inheritance was better in noncarriers than in patients (p < 0.001). Noncarriers were more aware than DM1 patients of the common clinical characteristics of DM1 such as limitations in physical activities and problems related to employment, schooling, activities of daily living, parenthood, peer relationships, and personality (p < 0.001). Compared to controls, DM1 patients felt less informed about the availability of clinical genetic services (p < 0.05) and new genetic technologies (p < 0.001). Among patients, logistic regression revealed that each additional year of education (p < 0.05) and each additional 100 CTG repeats (p < 0.01), respectively, increased and decreased the odds of knowing the DM1 mode of inheritance by about 23% and 18% respectively, independently of age, age at onset of symptoms, gender, severity of muscular impairment, and intellectual quotient. CONCLUSIONS: DM1 patients' genetic knowledge is significantly dependent of the level of education and the number of CTG repeats. Healthcare providers should be aware of this situation in order to adjust counselling and education accordingly.

Sexual dimorphism in the adolescent brain: Role of testosterone and androgen receptor in global and local volumes of grey and white matter.

Here we examined sex differences in the volumes of grey and white matter, and in grey-matter "density," in a group of typically developing adolescents participating in the Saguenay Youth Study (n=419; 12-18 years). In male adolescents, we also investigated the role of a functional polymorphism in androgen-receptor gene (AR) in moderating the effect of testosterone on volumes of grey and white matter and grey-matter density. Overall, both absolute and relative volumes of white matter were larger in male vs. females adolescents. The relative grey-matter volumes were slightly larger in female than male adolescents and so was the grey-matter density in a large number of cortical regions. In male adolescents, functional polymorphism of AR moderated the effect of testosterone on relative white- and grey-matter volumes. Following a discussion of several methodological and interpretational issues, we outline future directions in investigating brain-behavior relationships vis-à-vis psychopathology.

Sex differences in the growth of white matter during adolescence.

The purpose of this study was to examine sex differences in the maturation of white matter during adolescence (12 to 18 years of age). We measured lobular volumes of white matter and white-matter "density" throughout the brain using T1-weighted images, and estimated the myelination index using magnetisation-transfer ratio (MTR). In male adolescents, we observed age-related increases in white-matter lobular volumes accompanied by decreases in the lobular values of white-matter MTR. White-matter density in the putative cortico-spinal tract (pCST) decreased with age. In female adolescents, on the other hand, we found only small age-related increase in white-matter volumes and no age-related changes in white-matter MTR, with the exception of the frontal lobe where MTR increased. White-matter density in the pCST also increased with age. These results suggest that sex-specific mechanisms may underlie the growth of white matter during adolescence. We speculate that these mechanisms involve primarily age-related increases in axonal calibre in males and increased myelination in females.

Maternal cigarette smoking during pregnancy and cognitive performance in adolescence.

BACKGROUND: The incidence of cigarette smoking during pregnancy remains high. Maternal smoking during pregnancy is known to be associated with cognitive and behavioural sequelae in childhood and adolescence. We assessed the relationship between maternal cigarette smoking during pregnancy and cognitive abilities in adolescent offspring (n = 503, 12- to 18-years old) using an extensive 6-h battery of tests. METHODS: Non-exposed adolescents (controls) were matched to exposed adolescents (cases) by maternal education and school attended. Cognitive abilities were evaluated using a neuropsychological battery consisting of 33 tasks measuring verbal abilities, visuo-spatial skills, verbal and visual memory, processing speed, resistance to interference and motor dexterity. RESULTS: We found no differences between cases and controls in any of the cognitive domains whether potential confounders were included in the model or not. In addition to maternal smoking during pregnancy, we also evaluated the effect of sex and age on the various cognitive abilities in this large adolescent sample and found that most of the abilities continue to improve during adolescence to the same extent in girls and boys, with several age-independent sex differences. CONCLUSIONS: We found no effect of maternal cigarette smoking during pregnancy on cognitive abilities of the adolescent offspring when matching cases and controls by maternal education, the most common confounder of maternal cigarette smoking during pregnancy.

Reducing the harm of "harm reduction".

The article in this issue by Alan Leshner tackles one of the most contentious issues in drug use policy today and argues that we should dispense with "harm reduction" altogether--not the programs, policies, and interventions to which this term refers but the term itself. He makes the case that the initial clarity and simplicity of the phrase "harm reduction" have evolved into an emotion-laden designation that is interfering with the implementation and evaluation of public health programs.

Corpus callosum in adolescent offspring exposed prenatally to maternal cigarette smoking.

Teratogens, such as alcohol or anti-epileptic drugs, affect the size of the corpus callosum. Here we report findings obtained in a case-control study that investigated possible effects of teratogens contained in cigarette smoke on the size and structural properties of this structure. We recruited and scanned with magnetic resonance imaging a total of 408 adolescents (12 to 18 years of age); a subsample of 300 adolescents is considered in this report. Cases (n=146) were exposed to maternal cigarette smoking during pregnancy; non-exposed controls (n=154) were matched to cases by maternal education. We measured the size of corpus callosum (CC) and its sections (corrected for brain size), as well as mean values of magnetization-transfer ratio (MTR) in each CC section. Corpus callosum, and especially its posterior part, was smaller in the exposed vs. non-exposed female adolescents; no significant effects were found in males. Exposed and non-exposed subjects did not differ in the MTR-based index of myelination in either gender in any CC section. Given the lack of exposure effect on the myelination index, this finding might reflect a lower number of inter-hemispheric connections in female offspring of mothers who smoked during pregnancy.

The correlation of CTG repeat length with material and social deprivation in myotonic dystrophy.

Socioeconomic deprivation has long been recognized as a prominent feature of myotonic dystrophy type 1 (DM1), but studies performed before the discovery of the mutation causing DM1 may have suffered an ascertainment bias towards the more severe forms of the disease. We have sought to clarify the relationship between CTG repeats, muscular impairment, and socioeconomic characteristics of 200 patients with DM1. Patients with DM1 reported lower educational attainment, lower employment rate, lower family income, and higher reliance on social assistance than the reference population. Logistic regression showed, on one hand, that CTG repeats and marital status were significant predictors of social assistance recipiency and, on the other hand, that CTG repeats and gender were significant predictors of low social support from family, after adjustment for age, gender, degree of muscular impairment, CTG repeats, educational level, and marital status. For example, each additional 100 CTG repeats was found to increase the odds of relying on social assistance by about 35% and having low social support by about 22%. The chances of experiencing socioeconomic deprivation are loaded heavily against patients with DM1. The relationship between increased CTG repeat length and higher risk of material and social deprivation must be acknowledged in the clinical management of DM1.

Use of zeolite for removing ammonia and ammonia-caused toxicity in marine toxicity identification evaluations.

Ammonia occurs in marine waters including effluents, receiving waters, and sediment interstitial waters. At sufficiently high concentrations, ammonia can be toxic to aquatic species. Toxicity identification evaluation (TIE) methods provide researchers with tools for identifying aquatic toxicants. For identifying ammonia toxicity, there are several possible methods including pH alteration and volatilization, Ulva lactuca addition, microbial degradation, and zeolite addition. Zeolite addition has been used successfully in freshwater systems to decrease ammonia concentrations and toxicity for several decades. However, zeolite in marine systems has been used less because ions in the seawater interfere with zeolite's ability to adsorb ammonia. The objective of this study was to develop a zeolite method for removing ammonia from marine waters. To accomplish this objective, we performed a series of zeolite slurry and column chromatography studies to determine uptake rate and capacity and to evaluate the effects of salinity and pH on ammonia removal. We also assessed the interaction of zeolite with several toxic metals. Success of the methods was also evaluated by measuring toxicity to two marine species: the mysid Americamysis bahia and the amphipod Ampelisca abdita. Column chromatography proved to be effective at removing a wide range of ammonia concentrations under several experimental conditions. Conversely, the slurry method was inconsistent and variable in its overall performance in removing ammonia and cannot be recommended. The metals copper, lead, and zinc were removed by zeolite in both the slurry and column treatments. The zeolite column was successful in removing ammonia toxicity for both the mysid and the amphipod, whereas the slurry was less effective. This study demonstrated that zeolite column chromatography is a useful tool for conducting marine water TIEs to decrease ammonia concentrations and characterize toxicity.

The mystery of fungal infection in the guttural pouches.

Advances in the understanding of guttural pouch physiology and novel therapeutic approaches to mycotic infections in the horse are reviewed. It is suggested that the guttural pouches may contribute to the regulation of arterial blood temperature, cooling the circulation to the brain to below body temperature. Aspergillus spp. is the major organism found in a guttural pouch affected with mycosis but it is unclear why this agent becomes aggressive. Conventional therapy aims to prevent fatal haemorrhage and to treat any neurological lesions but it is desirable to try to prevent the disease. A technique consisting of inserting a transarterial coil into the internal carotid, external carotid and maxillary arteries in normal and affected horses has been reported to be rapid, safe and effective in occluding the arteries and in inducing regression of the mycotic lesions without adjunctive medical treatment. When faced with acute and uncontrollable epistaxis in the field, the most effective means to reduce haemorrhage is probably the occlusion of both common carotid arteries. However, how such arterial occlusions can result in the successful management of guttural pouch mycosis without antifungal medication remains a mystery.