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While global financial capital is abundant, it flows into corporate investments and real estate rather than climate change actions in cities. Political will and public pressure are crucial to redirecting funds. Studies of economic impacts underestimate the costs of climate disasters, especially in cities, so they undermine political commitments while understating potential climate-related returns. The shift of corporate approaches towards incorporating environmental, social, and governance (ESG) impacts offers promise for private-sector climate investments but are recently contested. Institutional barriers remain at all levels, particularly in African cities. Since the Global North controls the world's financial markets, new means of increasing funding for the Global South are needed, especially for adaptation. Innovative financial instruments and targeted use of environmental insurance tools can upgrade underdeveloped markets and align urban climate finance with ESG frameworks. These approaches, however, require climate impact data collection, programs to improve cities' and countries' creditworthiness, and trainings. This title is also available as open access on Cambridge Core.
Preclinical evidence suggests that diazepam enhances hippocampal γ-aminobutyric acid (GABA) signalling and normalises a psychosis-relevant cortico-limbic-striatal circuit. Hippocampal network dysconnectivity, particularly from the CA1 subfield, is evident in people at clinical high-risk for psychosis (CHR-P), representing a potential treatment target. This study aimed to forward-translate this preclinical evidence.
Methods
In this randomised, double-blind, placebo-controlled study, 18 CHR-P individuals underwent resting-state functional magnetic resonance imaging twice, once following a 5 mg dose of diazepam and once following a placebo. They were compared to 20 healthy controls (HC) who did not receive diazepam/placebo. Functional connectivity (FC) between the hippocampal CA1 subfield and the nucleus accumbens (NAc), amygdala, and ventromedial prefrontal cortex (vmPFC) was calculated. Mixed-effects models investigated the effect of group (CHR-P placebo/diazepam vs. HC) and condition (CHR-P diazepam vs. placebo) on CA1-to-region FC.
Results
In the placebo condition, CHR-P individuals showed significantly lower CA1-vmPFC (Z = 3.17, PFWE = 0.002) and CA1-NAc (Z = 2.94, PFWE = 0.005) FC compared to HC. In the diazepam condition, CA1-vmPFC FC was significantly increased (Z = 4.13, PFWE = 0.008) compared to placebo in CHR-P individuals, and both CA1-vmPFC and CA1-NAc FC were normalised to HC levels. In contrast, compared to HC, CA1-amygdala FC was significantly lower contralaterally and higher ipsilaterally in CHR-P individuals in both the placebo and diazepam conditions (lower: placebo Z = 3.46, PFWE = 0.002, diazepam Z = 3.33, PFWE = 0.003; higher: placebo Z = 4.48, PFWE < 0.001, diazepam Z = 4.22, PFWE < 0.001).
Conclusions
This study demonstrates that diazepam can partially restore hippocampal CA1 dysconnectivity in CHR-P individuals, suggesting that modulation of GABAergic function might be useful in the treatment of this clinical group.
This work attempts to better understand the significance of morphological diversity among fungal-algal contact zones present in lichens. We used TEM to examine a variety of lichen symbioses involving non-trebouxialean green algae that show intraparietal penetration by the mycobiont. A principal focus was on Endocarpon pusillum, a well-known member of a family (Verrucariaceae; Eurotiomycetes) previously reported to be characterized by unwalled haustoria exposing a naked fungal protoplast. Peg-like haustoria arose from an inner layer(s) of the mycobiont cell wall that broke through outer layers and penetrated a short distance into the wall of the green algal symbiont (Diplosphaera). In both fungal and algal cells at the contact interface, lomasome-like vesicles and tubules occurred as modifications of the plasmalemma intermixed with wall materials at the inner surface of the cell wall. A fungal cell wall was consistently present around the haustorium, which resembled those depicted in earlier TEM studies of Verrucariaceae. Previously published micrographs of Verrucariaceae purporting to show wall-less haustoria surrounded by an empty space are believed to have been misinterpreted. However, in the isidiose Porina and foliicolous Calopadia, Byssoloma and Fellhanera species (Lecanoromycetes), we did observe extreme degrees of reduction in the mycobiont cell wall at symbiont contact interfaces. In those lichens, a broad area of the fungal cell bulged into the adjacent algal symbiont, broadly invaginating the wall of the latter and penetrating it intraparietally without differentiation of a distinct haustorial structure. The mycobiont wall surrounding such protrusions often thinned to near indistinguishability towards its extremity. The protrusion made direct contact with the algal cell wall; no empty space occurred between them. We propose that the short, peg-like intraparietal haustoria bind the symbionts and help maintain cell contacts amid the stresses of tissue expansion and shrinkage, thereby avoiding disruption of the continuous hydrophobic coating that facilitates transfer between them. Broader contact interfaces with extremely thin adjacent walls may facilitate solute flow between symbionts. Reciprocal penetration of algal protrusions into mycobiont cells, noted in Porina as well as other lichens studied previously, is a neglected but potentially significant indication that both symbionts may actively work to maintain functional contact interfaces.
Low neuromuscular fitness is documented in adolescents with CHD and may be associated with clinical and morphological factors, indicating the need to assess strength in this population.
Objective:
To evaluate neuromuscular fitness with a multifactorial approach and its associations with other clinical and morphological factors in adolescents with CHD.
Methods:
This is an observational, cross-sectional study with adolescents with CHD, aged between 10 and 18 years. Neuromuscular fitness was calculated by the sum of the z-scores of four strength tests. Clinical factors of CHD were assessed by medical records and questionnaire. The morphological factors assessed were waist-to-height ratio, sum of skinfolds, and upper arm muscle area. Descriptive statistics, analysis of covariance, and linear regressions were performed.
Results:
Sixty adolescents with CHD participated, aged 12,7 ± 2,1 years, 55% girls. Maximum isometric strength was inadequate in 33%, jump height (power) in 33%, abdominal muscle strength resistance in 78%, and upper limb muscle strength resistance in 27%. Neuromuscular fitness was inadequate in 89% (n = 53) of adolescents with CHD. In the unadjusted regression, neuromuscular fitness was associated with arm muscle area (β = 0,12; p = 0,02; R2adj = 0,08) and in the unadjusted and adjusted regression it was lower in cyanotic (vs. acyanotic) CHDs (β = −1,76; p = 0,03 R2adj = 0,24).
Conclusion:
The findings reveal deficits in different presentations of musculoskeletal strength in a large proportion of adolescents with CHD, reinforcing the need to measure fitness from a broader perspective. Low muscle mass and the presence of cyanotic CHD may imply in reduced neuromuscular fitness in adolescents with CHD.
Individuals with schizophrenia experience significantly higher rates of chronic physical health conditions, driving a 20-year reduction in life expectancy. Poor diet quality is a key modifiable risk factor; however, owing to side-effects of antipsychotic medication, cognitive challenges and food insecurity, standard dietary counselling may not be sufficient for this population group.
Aim
To evaluate the feasibility, acceptability and preliminary effectiveness of two dietary interventions – pre-prepared meals and meal kits – for individuals with schizophrenia.
Method
The Schizophrenia, Nutrition and Choices in Kilojoules (SNaCK) study is a 12-week, three-arm, cross-over, randomised controlled trial. Eighteen participants aged 18–64 years diagnosed with schizophrenia or schizoaffective disorder will be recruited from community mental health services in Australia. Participants will be randomised to receive pre-prepared meals, meal kits or a supermarket voucher as a control, crossing-over at the end of weeks 4 and 8, so that all participants experience all three study arms. Primary outcomes include feasibility (recruitment rate and retention, number of days participants use pre-prepared meals or meal kits, adherence to meals as prescribed, difficulty in meal preparation and meal wastage) and acceptability (meal provision preference ranking and implementation) of the nutrition interventions. Secondary outcomes include the effects of the intervention on metabolic syndrome components, dietary intake, quality of life and food security measures.
Conclusions
Feasible, acceptable and effective dietary interventions for people with schizophrenia are urgently needed. Findings from this trial will inform future larger randomised controlled trials that have the potential to influence policy and improve health outcomes for this vulnerable population.
In a combined experimental and numerical effort, we investigate the generation and reduction of airfoil tonal noise. The means of noise control are streak generators in the form of cylindrical roughness elements. These elements are placed periodically along the span of the airfoil at the mid-chord streamwise position. Experiments are performed for a wide range of Reynolds numbers and angles of attack in a companion work (Alva et al., AIAA Aviation Forum, 2023). In the present work, we concentrate on numerical investigations for a further investigation of selected cases. We have performed wall-resolved large-eddy simulations for a NACA 0012 airfoil at zero angle of attack and Mach 0.3. Two Reynolds numbers (${0.8\times 10^{5}}$ and ${1.0 \times 10^{5}}$) have been investigated, showing acoustic results consistent with experiments at the same Reynolds but lower Mach numbers. Roughness elements attenuate tones in the acoustic field and, for the higher Reynolds number, suppress them. Through Fourier decomposition and spectral proper orthogonal decomposition analysis of streamwise velocity data, dominating structures have been identified. Further, the coupling between the structures generated by the surface roughness and the instability modes (Kelvin–Helmholtz) of the shear layer has been identified through stability analysis, suggesting stabilisation mechanisms by which the sound generation by the airfoil is reduced by the roughness elements.
Background: Efgartigimod, a human immunoglobulin G1 (IgG1) antibody Fc fragment, reduces IgG levels through neonatal Fc receptor blockade. Efgartigimod PH20 SC (1000-mg fixed dose, coformulated with recombinant human hyaluronidase PH20) is provided in a vial administered via a separate syringe (V+S). Here, we investigate bioequivalence, safety, and tolerability of efgartigimod PH20 SC administered via prefilled syringe (PFS) vs V+S in healthy participants. Methods: Bioequivalence was assessed in a phase 1, open-label study. Healthy participants (n=72) were randomized to receive one injection of efgartigimod PH20 SC via PFS or V+S in a crossover design. Separate studies evaluated feasibility of different injection speeds and usability of the PFS. Results: Bioequivalence between efgartigimod PH20 SC via PFS or V+S was established, as the 90% CI around the geometric least-squares mean ratio of Cmax and AUC0-inf was within predefined criteria (80.00%-125.00%). Most adverse events were mild to moderate. No observed differences in incidence of reported injection site reactions emerged. No serious adverse events or deaths occurred. Rapid (20-second) administration was feasible and the PFS could be safely prepared and administered by participants/caregivers. Conclusions: Efgartigimod PH20 SC administered via PFS is bioequivalent to efgartigimod PH20 SC administered via V+S, which may provide an additional convenient treatment option.
Background: The complement component C5 inhibitor, ravulizumab, is approved in Canada for the treatment of adults with AQP4-Ab+ NMOSD. Updated efficacy and safety results from the ongoing CHAMPION-NMOSD (NCT04201262) trial are reported. Methods: Participants received IV-administered, weight-based dosing of ravulizumab, with loading on day 1 and maintenance doses on day 15 and every 8 weeks thereafter. Following a primary treatment period (PTP; up to 2.5 years), patients could enter a long-term extension (LTE). Outcome measures included safety, time to first adjudicated on-trial relapse (OTR), risk reduction, and disability scores. Results: 56/41 patients entered/completed the LTE as of June 14, 2024. Median follow-up was 170.3 weeks (186.6 patient-years). No patients experienced an OTR. 94.8% (55/58 patients) had stable or improved Hauser Ambulation Index scores. 89.7% (52/58 patients) had no clinically important worsening in Expanded Disability Status Scale scores. Treatment-emergent adverse events (98.4%) were predominantly mild and unrelated to ravulizumab. Serious adverse events occurred in 25.9% of patients. Two cases of meningococcal infection occurred during the PTP, and none in the LTE. One unrelated death (cardiovascular) occurred during the LTE. Conclusions: Ravulizumab demonstrated long-term clinical benefit in AQP4-Ab+ NMOSD relapse prevention while maintaining or improving disability measures, with no new safety concerns.
Background: Efgartigimod, a human immunoglobulin (Ig)G1 antibody Fc fragment, blocks the neonatal Fc receptor, reducing IgGs involved in chronic inflammatory demyelinating polyneuropathy (CIDP). The multi-stage, double-blinded, placebo-controlled ADHERE (NCT04281472) and open-label extension ADHERE+ (NCT04280718) trials (interim analysis cutoff: February 16, 2024) assessed efgartigimod PH20 SC in participants with CIDP. Methods: Participants with active CIDP received open-label, weekly efgartigimod PH20 SC 1000 mg during ≤12-week run-in (stage-A). Responders were randomized (1:1) to efgartigimod or placebo for ≤48 weeks (stage-B). Participants with clinical deterioration in stage-B or who completed ADHERE entered ADHERE+. Week 36 changes from run-in baseline (CFB) in adjusted Inflammatory Neuropathy Cause and Treatment (aINCAT), Inflammatory Rasch-built Overall Disability Scale (I-RODS), and grip strength scores were evaluated. Results: Of 322 stage-A participants, 221 were randomized and treated in stage-B, and 99% entered ADHERE+. Mean CFB (SE) in aINCAT, I-RODS, and grip strength scores were -1.2 (0.15) and 8.8 (1.46) and 17.5 (2.02), respectively, at ADHERE+ Week 36 (N=150). Half the participants with clinical deterioration during ADHERE stage-B restabilized on efgartigimod from ADHERE+ Week 4. Conclusions: Interim results from ADHERE+ indicate long-term effectiveness of efgartigimod PH20 SC in clinical outcomes in participants with CIDP.
Background: Efgartigimod, a human immunoglobulin (Ig)G1 antibody Fc fragment, blocks the neonatal Fc receptor, reducing IgGs involved in chronic inflammatory demyelinating polyneuropathy (CIDP), a rare, progressive, immune-mediated disease that can lead to irreversible disability. The multi-stage, double-blinded, placebo-controlled ADHERE (NCT04281472) trial assessed efgartigimod PH20 SC in participants with CIDP. Methods: Participants with active CIDP received open-label, weekly efgartigimod PH20 SC 1000 mg during ≤12-week run-in (stage-A). Responders were randomized (1:1) to weekly efgartigimod or placebo for ≤48 weeks (stage-B). This posthoc analysis evaluated changes from run-in baseline (study enrollment) to stage-B last assessment and items of the Inflammatory Rasch-built Overall Disability Scale (I-RODS). Results: Of 322 participants who entered stage-A, 221 were randomized and treated in stage-B, and 191/221 had data for run-in baseline and post–stage-B timepoints. Mean (SE) I-RODS change at stage-B last assessment vs run-in baseline was 5.7 (1.88) and -4.9 (1.82) in participants randomized to efgartigimod and placebo, respectively. 37/97 (38.1%) and 24/92 (26.1%) participants randomized to efgartigimod and placebo, respectively, experienced ≥4-point improvements in I-RODS score. Efgartigimod-treated participants improved ≥1 point in I-RODS items of clinical interest. Conclusions: Participants who received efgartigimod in stage-B experienced improvements in I-RODS score from study enrollment to stage-B last assessment.
During pregnancy, colonization by genital mycoplasmas may be associated with adverse outcomes. This study was conducted to investigate the prevalence of four species of Mollicutes (Mycoplasma hominis, Mycoplasma genitalium, Ureaplasma parvum, and Ureaplasma urealyticum) in pregnant women receiving high-risk prenatal care and to evaluate possible associated factors. Data collection included the application of a questionnaire and the collection of cervical swabs from pregnant women. Species identification was performed by real-time PCR. The overall prevalence of Mollicutes was 60.97%. 55.9% of pregnant women were colonized by Ureaplasma spp., and 19.51% by Mycoplasma spp. The prevalence rates by species were 48.78% for U. parvum, 11.59% for U. urealyticum, 18.9% for M. hominis, and 1.22% for M. genitalium. Age, 12 years of schooling or more, age at first sexual intercourse up to 14 years, third trimester of pregnancy, having undergone infertility treatment, presence of STI, and groin lymph nodes were associated with a higher prevalence of microorganisms. The results presented are of utmost importance for understanding the prevalence of these microorganisms, the characteristics of colonized pregnant women, and planning screening strategies and interventions that minimize the negative impacts of these infections.
There is growing evidence that smoking increases the risk of developing psychiatric disorders, but the underlying mechanisms are largely unknown. We examine brain structure as a potential pathway between smoking and psychiatric disease liability.
Methods
We test associations between smoking (initiation, cigarettes per day, cessation, lifetime use) and depression, bipolar disorder, and schizophrenia, with and without correcting for volume of the amygdala, hippocampus, lateral and medial orbitofrontal cortex, superior frontal context, and cortical thickness and surface area. We use three methods that use summary statistics of genome-wide association studies to investigate genome-wide and local genetic overlap (genomic structural equation modeling, local analysis of (co)variant association), as well as causal associations (Mendelian randomization).
Results
While we find causal effects of smoking on brain volume in different brain areas, and with psychiatric disorders, brain volume did not seem to mediate the effect of smoking on psychiatric disorders.
Conclusions
While these findings are limited by characteristics of the included summary statistics (e.g. sample size), we conclude that brain volume of these areas is unlikely to explain a substantial part of any effect of smoking on psychiatric disorders. Nevertheless, genetic methods are valuable tools for exploring other potential mechanisms, such as brain functional connectivity, foregoing the need to collect all phenotypes in one dataset.
Electronic health records (EHRs), increasingly available in low- and middle-income countries (LMICs), provide an opportunity to study transdiagnostic features of serious mental illness (SMI) and its trajectories.
Aims
Characterise transdiagnostic features and diagnostic trajectories of SMI using an EHR database in an LMIC institution.
Method
We conducted a retrospective cohort study using EHRs from 2005–2022 at Clínica San Juan de Dios Manizales, a specialised mental health facility in Colombia, including 22 447 patients with schizophrenia (SCZ), bipolar disorder (BPD) or severe/recurrent major depressive disorder (MDD). Using diagnostic codes and clinical notes, we analysed the frequency of suicidality and psychosis across diagnoses, patterns of diagnostic switching and the accumulation of comorbidities. Mixed-effect logistic regression was used to identify factors influencing diagnostic stability.
Results
High frequencies of suicidality and psychosis were observed across diagnoses of SCZ, BPD and MDD. Most patients (64%) received multiple diagnoses over time, including switches between primary SMI diagnoses (19%), diagnostic comorbidities (30%) or both (15%). Predictors of diagnostic switching included mentions of delusions (odds ratio = 1.47, 95% CI 1.34–1.61), prior diagnostic switching (odds ratio = 4.01, 95% CI 3.7–4.34) and time in treatment, independent of age (log of visit number; odds ratio = 0.57, 95% CI 0.54–0.61). Over 80% of patients reached diagnostic stability within 6 years of their first record.
Conclusions
Integrating structured and unstructured EHR data reveals transdiagnostic patterns in SMI and predictors of disease trajectories, highlighting the potential of EHR-based tools for research and precision psychiatry in LMICs.
The stars of the Milky Way carry the chemical history of our Galaxy in their atmospheres as they journey through its vast expanse. Like barcodes, we can extract the chemical fingerprints of stars from high-resolution spectroscopy. The fourth data release (DR4) of the Galactic Archaeology with HERMES (GALAH) Survey, based on a decade of observations, provides the chemical abundances of up to 32 elements for 917 588 stars that also have exquisite astrometric data from the Gaia satellite. For the first time, these elements include life-essential nitrogen to complement carbon, and oxygen as well as more measurements of rare-earth elements critical to modern-life electronics, offering unparalleled insights into the chemical composition of the Milky Way. For this release, we use neural networks to simultaneously fit stellar parameters and abundances across the whole wavelength range, leveraging synthetic grids computed with Spectroscopy Made Easy. These grids account for atomic line formation in non-local thermodynamic equilibrium for 14 elements. In a two-iteration process, we first fit stellar labels to all 1 085 520 spectra, then co-add repeated observations and refine these labels using astrometric data from Gaia and 2MASS photometry, improving the accuracy and precision of stellar parameters and abundances. Our validation thoroughly assesses the reliability of spectroscopic measurements and highlights key caveats. GALAH DR4 represents yet another milestone in Galactic archaeology, combining detailed chemical compositions from multiple nucleosynthetic channels with kinematic information and age estimates. The resulting dataset, covering nearly a million stars, opens new avenues for understanding not only the chemical and dynamical history of the Milky Way but also the broader questions of the origin of elements and the evolution of planets, stars, and galaxies.
Selective serotonin reuptake inhibitors (SSRIs) are the preferred pharmacological treatment for obsessive–compulsive disorder (OCD). However, insufficient response is common and it remains unclear whether specific patient-level factors influence the likelihood of treatment response.
Aims
To determine the efficacy and acceptability of SSRIs in adult OCD, and to identify patient-level modifiers of efficacy.
Methods
We conducted an individual patient data meta-analysis (IPDMA) of industry-sponsored short-term, randomised, placebo-controlled SSRI trials submitted for approval to the Dutch regulatory agency to obtain marketing approval for treating OCD in adults. We performed a two-stage meta-analysis, using crude data of available trials. The primary outcome was the difference in Yale–Brown Obsessive–Compulsive Scale (YBOCS) change between active treatment and placebo. Secondary outcomes were differences in response (defined as the odds ratio of ≥35% YBOCS point reduction) and acceptability (defined as the odds ratio for all-cause discontinuation). We examined the modifying effect of baseline characteristics: age, gender, illness severity, depressive symptoms, weight, illness duration and history of antidepressant use.
Results
After excluding three trials because of missing data, we analysed results from 11 trials (79% of all submitted trials, n = 2372). The trial duration ranged from 10 to 13 weeks. Mean difference of SSRIs relative to placebo was 2.65 YBOCS points (95% CI 1.85–3.46, p < 0.0001), equalling a small effect size (0.33 Hedges’ g). The odds ratio for response was 2.21 in favour of active treatment (95% CI 1.72–2.83, p < 0.0001), with a number needed to treat of seven. Patient characteristics did not modify symptom change or response. Acceptability was comparable for SSRIs and placebo.
Conclusions
Our IPDMA showed that SSRIs are well accepted and superior to placebo for treating OCD. The effects are modest and independent of baseline patient characteristics.
It remains unclear which individuals with subthreshold depression benefit most from psychological intervention, and what long-term effects this has on symptom deterioration, response and remission.
Aims
To synthesise psychological intervention benefits in adults with subthreshold depression up to 2 years, and explore participant-level effect-modifiers.
Method
Randomised trials comparing psychological intervention with inactive control were identified via systematic search. Authors were contacted to obtain individual participant data (IPD), analysed using Bayesian one-stage meta-analysis. Treatment–covariate interactions were added to examine moderators. Hierarchical-additive models were used to explore treatment benefits conditional on baseline Patient Health Questionnaire 9 (PHQ-9) values.
Results
IPD of 10 671 individuals (50 studies) could be included. We found significant effects on depressive symptom severity up to 12 months (standardised mean-difference [s.m.d.] = −0.48 to −0.27). Effects could not be ascertained up to 24 months (s.m.d. = −0.18). Similar findings emerged for 50% symptom reduction (relative risk = 1.27–2.79), reliable improvement (relative risk = 1.38–3.17), deterioration (relative risk = 0.67–0.54) and close-to-symptom-free status (relative risk = 1.41–2.80). Among participant-level moderators, only initial depression and anxiety severity were highly credible (P > 0.99). Predicted treatment benefits decreased with lower symptom severity but remained minimally important even for very mild symptoms (s.m.d. = −0.33 for PHQ-9 = 5).
Conclusions
Psychological intervention reduces the symptom burden in individuals with subthreshold depression up to 1 year, and protects against symptom deterioration. Benefits up to 2 years are less certain. We find strong support for intervention in subthreshold depression, particularly with PHQ-9 scores ≥ 10. For very mild symptoms, scalable treatments could be an attractive option.
Parasite biodiversity is underestimated or unknown in many regions, yet information on parasites is critical to understanding ecosystem structure and how this will change into the future. Understanding the diversity and role of parasites is especially important in regions exposed to anthropogenic pressures, such as aquatic ecosystems, as their interactions with other stressors can either exacerbate or mediate negative impacts. Water scarcity in the Brazilian semi-arid has led to a proliferation of reservoirs for human use. These artificial waterbodies host a diversity of taxa, including a large number of fish species; however, fish parasite diversity remains undocumented. This study investigated the parasitological diversity of fishes from reservoirs in the Paraíba and Mamanguape River basins in the Caatinga domain, Brazil – one of the most populated semi-arid regions worldwide. Eight reservoirs were studied, with fish sampled across the two phases of the hydrological cycle (dry and rainy seasons) using gillnets, cast nets, and trawl nets. Endo- and ecto-parasites were identified and enumerated, and parasitological indices (prevalence, intensity, and abundance) were calculated. In total, 1,170 individuals of 21 fish species were examined. Of these individuals, 42% were parasitized with at least one of 54 parasite taxa. We recorded 32 new geographical occurrences of parasites and 23 new fish-parasite interactions, expanding our understanding of ichthyoparasite diversity in the Brazilian semi-arid. Moving forward, it is important to develop knowledge around how anthropogenic changes (e.g., biological invasions, climate, and land use change) influence host-parasite structure and dynamics and ecosystem functioning in these ecosystems.
The description and delineation of trematode species is a major ongoing task. Across the field there has been, and currently still is, great variation in the standard of this work and in the sophistication of the proposal of taxonomic hypotheses. Although most species are relatively unambiguously distinct from their congeners, many are either morphologically very similar, including the major and rapidly growing component of cryptic species, or are highly variable morphologically despite little to no molecular variation for standard DNA markers. Here we review challenges in species delineation in the context provided to us by the historical literature, and the use of morphological, geographical, host, and molecular data. We observe that there are potential challenges associated with all these information sources. As a result, we encourage careful proposal of taxonomic hypotheses with consideration for underlying species concepts and frank acknowledgement of weaknesses or conflict in the data. It seems clear that there is no single source of data that provides a wholly reliable answer to our taxonomic challenges but that nuanced consideration of information from multiple sources (the ‘integrated approach’) provides the best possibility of developing hypotheses that will stand the test of time.
Toxoplasma gondii non-archetypal strains have distinct virulence profiles and immunological activation in the host when compared with archetypal strains. The present work aims to perform an analysis of the inflammatory profile during acute and early chronic infection by T. gondii atypical strain in an experimental murine model. After euthanasia, blood was collected for the quantification of specific IgG antibodies and their subtypes (IgG1/IgG3) by ELISA; bronchoalveolar lavage (BAL) was realized and immunophenotyping of lymphocytes population was performed at 12- and 30-days post infection (dpi); the levels of IFN-γ, IL-12, IL-10, TNF-α, IL-6, IL-17, nitric oxide and total proteins were determined in the BAL supernatant. Tissue cyst burden was determined in the brain homogenate, and the parasite load in the lungs was assessed by quantitative reverse transcription polymerase chain reaction (qRT-PCR). Infection with the CK4 strain induced a lower brain cyst load similar parasite burden in the lungs, and higher levels of IgG1 and IgG3, when compared to ME49. The group infected with the CK4 strain presented higher levels of systemic IFN-γ, and both infected groups displayed similarly elevated levels of systemic TNF-α, IL-6 and IL-17 at 30 dpi, as well as higher numbers of CD4+ and CD8+ T lymphocytes in the acute stage of infection, followed by higher numbers of central and effector CD4+ T cells. IFN-γ levels in the BAL fluid were significantly higher in animals infected with the CK4 strain in both the acute and early chronic stage of infection, highlighting the involvement of the lung environment.