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1.
Oecologia ; 2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-38995365

RESUMEN

Although intraspecific trait variation is increasingly recognized as affecting ecosystem processes, few studies have examined the ecological significance of among-population variation in behavioral traits in natural ecosystems. In freshwater habitats, crayfish are consumers that can influence ecosystem structure (e.g., macroinvertebrate communities) and function (e.g., leaf litter breakdown). To test whether crayfish behavioral traits (activity, boldness, and foraging voracity) are major contributors of leaf litter breakdown rates in the field, we collected rusty crayfish (Faxonius rusticus) from eight streams across the midwestern USA and measured behaviors using laboratory assays. At the same streams, we measured breakdown rates of leaf packs that were accessible or inaccessible to crayfish. Our results provide evidence that among-population variation in crayfish boldness and foraging voracity was a strong predictor of leaf litter breakdown rates, even after accounting for commonly appreciated environmental drivers (water temperature and human land use). Our results suggest that less bold rusty populations (i.e., emerged from shelter more slowly) had greater direct impacts on leaf litter breakdown than bold populations (P = 0.001, r2 = 0.85), potentially because leaf packs can be both a shelter and food resource to crayfish. Additionally, we found that foraging voracity was negatively related to breakdown rates in leaf packs that were inaccessible to crayfish (P = 0.025, r2 = 0.60), potentially due to a trophic cascade from crayfish preying on other invertebrates that consume leaf litter. Overall, our results add to the growing evidence that trait variation in animals may be important for understanding freshwater ecosystem functioning.

3.
Nature ; 630(8018): 836-840, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38768634

RESUMEN

Interactions between exoplanetary atmospheres and internal properties have long been proposed to be drivers of the inflation mechanisms of gaseous planets and apparent atmospheric chemical disequilibrium conditions1. However, transmission spectra of exoplanets have been limited in their ability to observationally confirm these theories owing to the limited wavelength coverage of the Hubble Space Telescope (HST) and inferences of single molecules, mostly H2O (ref. 2). In this work, we present the panchromatic transmission spectrum of the approximately 750 K, low-density, Neptune-sized exoplanet WASP-107b using a combination of HST Wide Field Camera 3 (WFC3) and JWST Near-Infrared Camera (NIRCam) and Mid-Infrared Instrument (MIRI). From this spectrum, we detect spectroscopic features resulting from H2O (21σ), CH4 (5σ), CO (7σ), CO2 (29σ), SO2 (9σ) and NH3 (6σ). The presence of these molecules enables constraints on the atmospheric metal enrichment (M/H is 10-18× solar3), vertical mixing strength (log10Kzz = 8.4-9.0 cm2 s-1) and internal temperature (>345 K). The high internal temperature is suggestive of tidally driven inflation4 acting on a Neptune-like internal structure, which can naturally explain the large radius and low density of the planet. These findings suggest that eccentricity-driven tidal heating is a critical process governing atmospheric chemistry and interior-structure inferences for most of the cool (<1,000 K) super-Earth-to-Saturn-mass exoplanet population.

4.
Ecol Evol ; 14(3): e11152, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38495432

RESUMEN

The endangered population of humpback whales (Megaptera novaeangliae) breeding and calving off the Cape Verde Islands (CVI) are known to migrate to feeding areas located along the eastern margin of the North Atlantic Ocean (Iceland, and Norway). Here, we report for the first time a confirmed migration of an individual humpback whale from CVI breeding ground to a western North Atlantic feeding ground of West Greenland. This individual humpback, which was photographed and identified off the coast of West Greenland in 2021, was previously documented in CVI 22 years before (1999). An annual subsistence hunt for humpbacks occurs in West Greenland and the resighting at this location with a humpback whale from CVI has strong implications for the conservation efforts of the small CVI population.

5.
J Nutr Educ Behav ; 56(5): 321-331, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38466246

RESUMEN

OBJECTIVE: To assess the impact of the Philadelphia Beverage Tax on perceived beverage healthfulness, and awareness and opinions of the tax. DESIGN: Natural experiment SETTING: Small independent stores in Philadelphia (n = 61) and Baltimore (untaxed control site; n = 65) PARTICIPANTS: Shoppers in Philadelphia (n = 2,731) and Baltimore (n = 4,600) pre- and post-tax implementation. MAIN OUTCOME MEASURES: Perceptions of 4 beverages (unhealthy vs healthy/neutral), tax awareness, and tax opinions (oppose vs favor/neutral). ANALYSIS: Mixed-effects linear probability models estimated changes in perceived beverage healthfulness in Philadelphia, relative to Baltimore, following a difference-in-differences approach. Mixed-effects linear probability models estimated pre-post changes in tax awareness and opinions in Philadelphia-only. RESULTS: The probability of perceiving taxed beverages as unhealthy increased 2-years post-tax relative to Baltimore (regular soda: 5.7% [95% confidence interval (CI), 0.9-10.6], P = 0.02; diet soda: 7.7% [95% CI, 1.5-13.8], P < 0.001; sports drinks: 6.4% [95% CI, 0.4-12.4], P = 0.04), with similar changes at 1-year post-tax, whereas perceived healthfulness of untaxed 100% fruit juice did not change. Tax awareness was high at baseline (72%) and increased post-implementation; however, the probability of opposing the tax (22%) also increased over time. CONCLUSIONS AND IMPLICATIONS: Decreases in the perceived healthfulness of taxed beverages suggest the tax had a health-signaling effect. Consumer awareness and health education efforts could complement tax policies to enhance understanding of health risks.


Asunto(s)
Bebidas , Impuestos , Humanos , Philadelphia , Femenino , Masculino , Adulto , Bebidas/economía , Baltimore , Persona de Mediana Edad , Conocimientos, Actitudes y Práctica en Salud
6.
Nat Microbiol ; 9(3): 763-775, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38336881

RESUMEN

Many bacterial surface glycans such as the peptidoglycan (PG) cell wall are built from monomeric units linked to a polyprenyl lipid carrier. How this limiting carrier is distributed among competing pathways has remained unclear. Here we describe the isolation of hyperactive variants of Pseudomonas aeruginosa MraY, the enzyme that forms the first lipid-linked PG precursor. These variants result in the elevated production of the final PG precursor lipid II in cells and are hyperactive in vitro. The activated MraY variants have substitutions that map to a cavity on the extracellular side of the dimer interface, far from the active site. Our structural and molecular dynamics results suggest that this cavity is a binding site for externalized lipid II. Overall, our results support a model in which excess externalized lipid II allosterically inhibits MraY, providing a feedback mechanism that prevents the sequestration of lipid carrier in the PG biogenesis pathway.


Asunto(s)
Bacterias , Pseudomonas aeruginosa , Pseudomonas aeruginosa/genética , Retroalimentación , Pared Celular/metabolismo , Lípidos
7.
J Autism Dev Disord ; 54(4): 1264-1280, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36697931

RESUMEN

Youth with autism spectrum disorder (ASD) often experience difficulties related to aggression, disruptive behavior, and regulation of emotions that precipitate these behaviors (i.e., anger). The extent to which aggression, disruptive behaviors, and anger dysregulation are correlated with distinct or overlapping factors has not yet been explored. The present study examined whether aspects of participant demographics, individual youth functioning, caregiver stress, and family warmth contributed to youth aggression, disruptive behavior, and anger dysregulation. Participants were caregivers of 511 youths with ASD. Analyses revealed that significant proportions of variance in aggression, disruptive behaviors, and anger dysregulation were accounted for by shared variables pertaining to demographics, the individual youth, and caregiver stress. Implications of treatment and future research are discussed.


Asunto(s)
Trastorno del Espectro Autista , Problema de Conducta , Humanos , Adolescente , Agresión/psicología , Trastorno del Espectro Autista/psicología , Ira , Emociones
8.
J Autism Dev Disord ; 54(3): 829-840, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36626008

RESUMEN

Increased stress among parents of youth with ASD has been well-documented. However, research on aspects of the parent-child relationship and subsequent links to parenting stress is limited. We assessed parents (N = 511) of youth with ASD to examine relations between parenting stress and parent-child quality time (amount of quality time, shared enjoyment, synchronicity). Elevated parenting stress was associated with less time spent engaging with youth in shared activities and decreased parent and child enjoyment during shared interactions. Parents with elevated stress reported engaging in shared activities and experiencing synchronicity with their child less often than parents below the clinical threshold. Future research should emphasize longitudinal efforts examining the directionality of this relationship to better inform family-focused intervention.


Asunto(s)
Trastorno del Espectro Autista , Humanos , Adolescente , Responsabilidad Parental , Felicidad , Placer , Relaciones Padres-Hijo
9.
Cancer Res Commun ; 4(1): 134-151, 2024 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-38112643

RESUMEN

Wnt ligand WNT4 is critical in female reproductive tissue development, with WNT4 dysregulation linked to related pathologies including breast cancer (invasive lobular carcinoma, ILC) and gynecologic cancers. WNT4 signaling in these contexts is distinct from canonical Wnt signaling yet inadequately understood. We previously identified atypical intracellular activity of WNT4 (independent of Wnt secretion) regulating mitochondrial function, and herein examine intracellular functions of WNT4. We further examine how convergent mechanisms of WNT4 dysregulation impact cancer metabolism. In ILC, WNT4 is co-opted by estrogen receptor α (ER) via genomic binding in WNT4 intron 1, while in gynecologic cancers, a common genetic polymorphism (rs3820282) at this ER binding site alters WNT4 regulation. Using proximity biotinylation (BioID), we show canonical Wnt ligand WNT3A is trafficked for secretion, but WNT4 is localized to the cytosol and mitochondria. We identified DHRS2, mTOR, and STAT1 as putative WNT4 cytosolic/mitochondrial signaling partners. Whole metabolite profiling, and integrated transcriptomic data, support that WNT4 mediates metabolic reprogramming via fatty acid and amino acid metabolism. Furthermore, ovarian cancer cell lines with rs3820282 variant genotype are WNT4 dependent and have active WNT4 metabolic signaling. In protein array analyses of a cohort of 103 human gynecologic tumors enriched for patient diversity, germline rs3820282 genotype is associated with metabolic remodeling. Variant genotype tumors show increased AMPK activation and downstream signaling, with the highest AMPK signaling activity in variant genotype tumors from non-White patients. Taken together, atypical intracellular WNT4 signaling, in part via genetic dysregulation, regulates the distinct metabolic phenotypes of ILC and gynecologic cancers. SIGNIFICANCE: WNT4 regulates breast and gynecologic cancer metabolism via a previously unappreciated intracellular signaling mechanism at the mitochondria, with WNT4 mediating metabolic remodeling. Understanding WNT4 dysregulation by estrogen and genetic polymorphism offers new opportunities for defining tumor biology, precision therapeutics, and personalized cancer risk assessment.


Asunto(s)
Neoplasias de la Mama , Neoplasias de los Genitales Femeninos , Humanos , Femenino , Ligandos , Proteínas Quinasas Activadas por AMP/metabolismo , Neoplasias de los Genitales Femeninos/genética , Transducción de Señal , Neoplasias de la Mama/genética , Proteína Wnt4/genética , Carbonil Reductasa (NADPH)/metabolismo
10.
Nature ; 623(7988): 709-712, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37993572

RESUMEN

The abundances of main carbon- and oxygen-bearing gases in the atmospheres of giant exoplanets provide insights into atmospheric chemistry and planet formation processes1,2. Thermochemistry suggests that methane (CH4) should be the dominant carbon-bearing species below about 1,000 K over a range of plausible atmospheric compositions3; this is the case for the solar system planets4 and has been confirmed in the atmospheres of brown dwarfs and self-luminous, directly imaged exoplanets5. However, CH4 has not yet been definitively detected with space-based spectroscopy in the atmosphere of a transiting exoplanet6-11, but a few detections have been made with ground-based, high-resolution transit spectroscopy12,13 including a tentative detection for WASP-80b (ref. 14). Here we report transmission and emission spectra spanning 2.4-4.0 µm of the 825 K warm Jupiter WASP-80b taken with the NIRCam instrument of the JWST, both of which show strong evidence of CH4 at greater than 6σ significance. The derived CH4 abundances from both viewing geometries are consistent with each other and with solar to sub-solar C/O and around five times solar metallicity, which is consistent with theoretical predictions15-17.

11.
Data Brief ; 50: 109621, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37823063

RESUMEN

This dataset presents global soil organic carbon stocks in mangrove forests at 30 m resolution, predicted for 2020. We used spatiotemporal ensemble machine learning to produce predictions of soil organic carbon content and bulk density (BD) to 1 m soil depth, which were then aggregated to calculate soil organic carbon stocks. This was done by using training data points of both SOC (%) and BD in mangroves from a global dataset and from recently published studies, and globally consistent predictive covariate layers. A total of 10,331 soil samples were validated to have SOC (%) measurements and were used for predictive soil mapping. We used time-series remote sensing data specific to time periods when the training data were sampled, as well as long-term (static) layers to train an ensemble of machine learning model. Ensemble models were used to improve performance, robustness and unbiasedness as opposed to just using one learner. In addition, we performed spatial cross-validation by using spatial blocking of training data points to assess model performance. We predicted SOC stocks for the 2020 time period and applied them to a 2020 mangrove extent map, presenting both mean predictions and prediction intervals to represent the uncertainty around our predictions. Predictions are available for download under CC-BY license from 10.5281/zenodo.7729491 and also as Cloud-Optimized GeoTIFFs (global mosaics).

12.
Obes Surg ; 33(12): 3841-3849, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37816973

RESUMEN

INTRODUCTION: The role of the common channel length in duodenal switch (DS) on remission of type II diabetes mellitus (DM), when stratifying patients based on diabetes severity, is not well understood. METHODS: We retrospectively reviewed 341 consecutive patients with DM undergoing DS with one of three different common channel (CC) lengths (100 cm, 150 cm, and 200 cm), each with a fixed 300 cm alimentary limb (AL). Patients were stratified by insulin dependence (IDDM) versus non-insulin dependent diabetes (NIDDM). Data was collected at one year and at the last available follow-up. RESULTS: The NIDDM group had a similar average HbA1c at last follow-up for each of the CC lengths. However, the IDDM group had lower average HbA1c with shorter CC lengths (100 cm = 5.4%, 150 cm = 6%, 200 cm = 6.4%, p < 0.05). Shorter CC lengths resulted in a greater proportion of patients achieving remission in the IDDM group (66%, 50%, 32% in the 100 cm, 150 cm, and 200 cm CC, respectively, p < 0.01). Improvements in HbA1c were independent of weight loss and average DiaRem scores were similar between CC lengths. Rates of nutritional deficiencies were higher in shorter common channel lengths. Revision for malnutrition was similar between common channel lengths (100 cm group: 3.7%; 150 cm group: 1.8%; 200 cm group: 0%, p = NS). CONCLUSIONS: When the AL is fixed, shortening CC lengths results in improved glycemic control and remission of DM in patients with the need for insulin preoperatively. Milder forms of DM are treated well with any of the CC lengths.


Asunto(s)
Desviación Biliopancreática , Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Insulinas , Desnutrición , Obesidad Mórbida , Humanos , Obesidad Mórbida/cirugía , Desviación Biliopancreática/métodos , Diabetes Mellitus Tipo 2/cirugía , Estudios Retrospectivos , Hemoglobina Glucada , Diabetes Mellitus Tipo 1/cirugía , Desnutrición/cirugía , Duodeno/cirugía
13.
Cell Mol Life Sci ; 80(9): 274, 2023 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-37650943

RESUMEN

BACKGROUND: The stage, when tissues and organs are growing, is very vulnerable to environmental influences, but it's not clear how exposure during this time causes changes to the epigenome and increases the risk of hormone-related illnesses like uterine fibroids (UFs). METHODS: Developmental reprogramming of myometrial stem cells (MMSCs), the putative origin from which UFs originate, was investigated in vitro and in the Eker rat model by RNA-seq, ChIP-seq, RRBS, gain/loss of function analysis, and luciferase activity assays. RESULTS: When exposed to the endocrine-disrupting chemical (EDC) diethylstilbestrol during Eker rat development, MMSCs undergo a reprogramming of their estrogen-responsive transcriptome. The reprogrammed genes in MMSCs are known as estrogen-responsive genes (ERGs) and are activated by mixed lineage leukemia protein-1 (MLL1) and DNA hypo-methylation mechanisms. Additionally, we observed a notable elevation in the expression of ERGs in MMSCs from Eker rats exposed to natural steroids after developmental exposure to EDC, thereby augmenting estrogen activity. CONCLUSION: Our studies identify epigenetic mechanisms of MLL1/DNA hypo-methylation-mediated MMSC reprogramming. EDC exposure epigenetically targets MMSCs and leads to persistent changes in the expression of a subset of ERGs, imparting a hormonal imprint on the ERGs, resulting in a "hyper-estrogenic" phenotype, and increasing the hormone-dependent risk of UFs.


Asunto(s)
Disruptores Endocrinos , Leiomioma , Animales , Ratas , Disruptores Endocrinos/toxicidad , Estrógenos , Bioensayo , Leiomioma/inducido químicamente , Leiomioma/genética , Proteína de la Leucemia Mieloide-Linfoide , ADN
14.
bioRxiv ; 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37577621

RESUMEN

Many bacterial surface glycans such as the peptidoglycan (PG) cell wall, O-antigens, and capsules are built from monomeric units linked to a polyprenyl lipid carrier. How this limiting lipid carrier is effectively distributed among competing pathways has remained unclear for some time. Here, we describe the isolation and characterization of hyperactive variants of Pseudomonas aeruginosa MraY, the essential and conserved enzyme catalyzing the formation of the first lipid-linked PG precursor called lipid I. These variants result in the elevated production of the final PG precursor lipid II in cells and are hyperactive in a purified system. Amino acid substitutions within the activated MraY variants unexpectedly map to a cavity on the extracellular side of the dimer interface, far from the active site. Our structural evidence and molecular dynamics simulations suggest that the cavity is a binding site for lipid II molecules that have been transported to the outer leaflet of the membrane. Overall, our results support a model in which excess externalized lipid II allosterically inhibits MraY, providing a feedback mechanism to prevent the sequestration of lipid carrier in the PG biogenesis pathway. MraY belongs to the broadly distributed polyprenyl-phosphate N-acetylhexosamine 1-phosphate transferase (PNPT) superfamily of enzymes. We therefore propose that similar feedback mechanisms may be widely employed to coordinate precursor supply with demand by polymerases, thereby optimizing the partitioning of lipid carriers between competing glycan biogenesis pathways.

15.
J Endocr Soc ; 7(8): bvad080, 2023 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-37409182

RESUMEN

Context: One in 8 women will develop breast cancer in their lifetime. Yet, the burden of disease is greater in Black women. Black women have a 40% higher mortality rate than White women, and a higher incidence of breast cancer at age 40 and younger. While the underlying cause of this disparity is multifactorial, exposure to endocrine disrupting chemicals (EDCs) in hair and other personal care products has been associated with an increased risk of breast cancer. Parabens are known EDCs that are commonly used as preservatives in hair and other personal care products, and Black women are disproportionately exposed to products containing parabens. Objective: Studies have shown that parabens impact breast cancer cell proliferation, death, migration/invasion, and metabolism, as well as gene expression in vitro. However, these studies were conducted using cell lines of European ancestry; to date, no studies have utilized breast cancer cell lines of West African ancestry to examine the effects of parabens on breast cancer progression. Like breast cancer cell lines with European ancestry, we hypothesize that parabens promote protumorigenic effects in breast cancer cell lines of West African ancestry. Methods: Luminal breast cancer cell lines with West African ancestry (HCC1500) and European ancestry (MCF-7) were treated with biologically relevant doses of methylparaben, propylparaben, and butylparaben. Results: Following treatment, estrogen receptor target gene expression and cell viability were examined. We observed altered estrogen receptor target gene expression and cell viability that was paraben and cell line specific. Conclusion: This study provides greater insight into the tumorigenic role of parabens in the progression of breast cancer in Black women.

16.
Int J Mol Sci ; 24(14)2023 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-37511399

RESUMEN

The period during which tissue and organ development occurs is particularly vulnerable to the influence of environmental exposures. However, the specific mechanisms through which biological pathways are disrupted in response to developmental insults, consequently elevating the risk of hormone-dependent diseases, such as uterine fibroids (UFs), remain poorly understood. Here, we show that developmental exposure to the endocrine-disrupting chemical (EDC), diethylstilbestrol (DES), activates the inflammatory pathways in myometrial stem cells (MMSCs), which are the origin of UFs. Significantly, the secretome of reprogrammed MMSCs enhances the expression of critical inflammation-related genes in differentiated myometrial cells through the paracrine mechanism, which amplifies pro-inflammatory and immune suppression signaling in the myometrium. The expression of reprogrammed inflammatory responsive genes (IRGs) is driven by activated mixed-lineage leukemia protein-1 (MLL1) in MMSCs. The deactivation of MLL reverses the reprogramming of IRG expression. In addition, the inhibition of histone deacetylases (HDACs) also reversed the reprogrammed IRG expression induced by EDC exposure. This work identifies the epigenetic mechanisms of MLL1/HDAC-mediated MMSC reprogramming, and EDC exposure epigenetically targets MMSCs and imparts an IRG expression pattern, which may result in a "hyper-inflammatory phenotype" and an increased hormone-dependent risk of UFs later in life.


Asunto(s)
Leiomioma , Neoplasias Uterinas , Femenino , Humanos , Miometrio/metabolismo , Leiomioma/genética , Leiomioma/metabolismo , Células Madre/metabolismo , Hormonas/metabolismo , Epigénesis Genética , Neoplasias Uterinas/genética
18.
J Invertebr Pathol ; 199: 107948, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37276935

RESUMEN

Crayfish have strong ecological impacts in freshwater systems, yet our knowledge of their parasites is limited. This study describes the first systemic microsporidium (infects multiple tissue types) Alternosema astaquatica n. sp. (Enterocytozoonida) isolated from a crayfish host, Faxonius virilis, using histopathology, transmission electron microscopy, gene sequencing, and phylogenetics. The parasite develops in direct contact with the host cell cytoplasm producing mature spores that are monokaryotic and ellipsoid in shape. Spores have 9-10 coils of the polar filament and measure 3.07 ± 0.26 µm (SD) in length and 0.93 ± 0.08 µm (SD) in width. Our novel isolate has high genetic similarity to Alternosema bostrichidis isolated from terrestrial beetles; however, genetic data from this parasite is restricted to a small fragment (396 bp) of the SSU gene. Additional data related to spore morphology and development, host, environment, and ecology indicate that our novel isolate is distinct from A. bostrichidis, which supports a new species description. Alternosema astaquatica n. sp. represents a novel member of the Orthosomella-like group which appears to be a set of opportunists within the Enterocytozoonida. The presence of this microsporidium in F. virilis could be relevant for freshwater ecosystems across this crayfish's broad geographic range in North America and may affect interactions between F. virilis and invasive rusty crayfish Faxonius rusticus in the Midwest USA.


Asunto(s)
Microsporidios , Parásitos , Animales , Microsporidios/genética , Astacoidea , Ecosistema , Filogenia
19.
J Invertebr Pathol ; 199: 107949, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37276936

RESUMEN

Crayfishes are among the most widely introduced freshwater taxa and can have extensive ecological impacts. Knowledge of the parasites crayfish harbor is limited, yet co-invasion of parasites is a significant risk associated with invasions. In this study, we describe a novel microsporidium, Cambaraspora faxoni n. sp. (Glugeida: Tuzetiidae), from two crayfish hosts in the Midwest USA, Faxonius virilis and Faxonius rusticus. We also expand the known host range of Cambaraspora floridanus to include Procambarus spiculifer. Cambaraspora faxoni infects muscle and heart tissue of F. rusticus and develops within a sporophorous vesicle. The mature spore measures 3.22 ± 0.14 µm in length and 1.45 ± 0.13 µm in width, with 8-9 turns of the polar filament. SSU sequencing indicates the isolates from F. virilis and F. rusticus were identical (100%) and 93.49% similar to C. floridanus, supporting the erection of a new species within the Cambaraspora genus. The novel parasite was discovered within the native range of F. rusticus (Ohio, USA) and within a native congeneric (F. virilis) in the invasive range of F. rusticus (Wisconsin, USA). Faxonius virilis is invasive in other regions. This new parasite could have been introduced to Wisconsin with F. rusticus or it may be a generalist species with a broad distribution. In either case, this parasite infects two crayfish species that have been widely introduced to new drainages throughout North America and could have future effects on invasion dynamics or impacts.


Asunto(s)
Microsporidios , Animales , Microsporidios/genética , Astacoidea/parasitología , Ambiente , Wisconsin
20.
Front Neurosci ; 17: 1177458, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37274219

RESUMEN

Introduction: Neuropeptide signaling modulates the function of central clock neurons in the suprachiasmatic nucleus (SCN) during development and adulthood. Arginine vasopressin (AVP) and vasoactive intestinal peptide (VIP) are expressed early in SCN development, but the precise timing of transcriptional onset has been difficult to establish due to age-related changes in the rhythmic expression of each peptide. Methods: To provide insight into spatial patterning of peptide transcription during SCN development, we used a transgenic approach to define the onset of Avp and Vip transcription. Avp-Cre or Vip-Cre males were crossed to Ai9+/+ females, producing offspring in which the fluorescent protein tdTomato (tdT) is expressed at the onset of Avp or Vip transcription. Spatial patterning of Avp-tdT and Vip-tdT expression was examined at critical developmental time points spanning mid-embryonic age to adulthood in both sexes. Results: We find that Avp-tdT and Vip-tdT expression is initiated at different developmental time points in spatial subclusters of SCN neurons, with developmental patterning that differs by sex. Conclusions: These data suggest that SCN neurons can be distinguished into further subtypes based on the developmental patterning of neuropeptide expression, which may contribute to regional and/or sex differences in cellular function in adulthood.

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