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1.
Aquat Toxicol ; 275: 107061, 2024 Oct.
Article de Anglais | MEDLINE | ID: mdl-39217789

RÉSUMÉ

Microplastics (MPs) are becoming increasingly common in freshwater ecosystems. Rotifers may involuntarily ingest MPs through non-selective filtration, thus causing non-real satiety, leading to adverse effects on their demography. Here, we evaluated the acute and chronic effects of MPs (30 µm) on two successive generations of Brachionus calyciflorus s.s. at 20 and 25 °C. Demographic variables and ingestion rates were compared in the absence and presence of microplastics (550 spheres mL-1). For the life table experiments, cohorts of twenty neonates were introduced into 20 mL medium with four replicates per treatment. Ingestion rates of the rotifer were tested at both test temperatures in the absence and presence of the microplastics in 20 mL containers with 1 ind. mL-1 per container. The rotifer population growth rates ranged from 0.55 to 1.05 d-1 depending on the treatment. MPs decreased the fecundity by 20-24 %. The average lifespan of rotifers exposed to MPs in the F0 generation was lower than that in the F1 generation at both temperatures, indicating that pre-exposure of mothers may offer some protection to the offspring. The population growth rate was higher at 25 °C. The ingestion rates were significantly lower in the presence of the microplastics. Our observations indicated that this strain of B. calyciflorus was better adapted to 20 °C; microplastics and higher test temperature resulted in a pronounced changes in the demographic variables of the rotifer.


Sujet(s)
Microplastiques , Rotifera , Polluants chimiques de l'eau , Animaux , Rotifera/effets des médicaments et des substances chimiques , Polluants chimiques de l'eau/toxicité , Microplastiques/toxicité , Température , Croissance démographique , Fécondité/effets des médicaments et des substances chimiques
2.
Chemosphere ; 365: 143355, 2024 Oct.
Article de Anglais | MEDLINE | ID: mdl-39299462

RÉSUMÉ

Plastic contamination in aquatic ecosystems all around the world is on the rise. Microplastics (MPs) interfere with the ecological functions of different aquatic animals, including zooplankton. Other contaminants can also be transported by microplastics, resulting in higher toxicity. Here, we evaluated the effect of microplastics alone and in combination with cyanotoxins (CT) on the demographic and feeding responses of the freshwater rotifer Brachionus calyciflorus. The microplastics used were polystyrene spheres of 30 µm diameter. The cyanobacteria were obtained from a sample collected from the Valle de Bravo reservoir in Central Mexico, and the secondary metabolites were obtained after 5 cycles of freezing, thawing and sonication. We conducted acute (LC50, 24h bioassay) and chronic toxicity tests involving population growth, life table experiments, and feeding experiments. The LC50 value using microplastics was 21.91 mg/L, and for the cyanobacterial crude extract it was 2.56 µg/L, but the combination of both resulted in a higher adverse effect (16.64 mg/L) due to the microplastics. Rotifer survival, reproduction, and feeding decreased in the presence of either MPs or CT but the adverse effect was more in the presence of both contaminants. We found that the adverse effects of MPs and CT on the test rotifer species were enhanced when exposed to both contaminants simultaneously.


Sujet(s)
Cyanobactéries , Microplastiques , Rotifera , Polluants chimiques de l'eau , Animaux , Rotifera/effets des médicaments et des substances chimiques , Microplastiques/toxicité , Polluants chimiques de l'eau/toxicité , Microcystines/toxicité , Reproduction/effets des médicaments et des substances chimiques , Mexique
3.
Cureus ; 16(6): e63377, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-39077304

RÉSUMÉ

Introduction Urolithiasis, a common urological disorder affecting the global population, demonstrates geographical diversity due to factors such as water quality, climate variations, health conditions, and dietary habits. This study, conducted in Northern Sri Lanka, examines urinary stone compositions and assesses the prevalence of metabolic disorders among urolithiasis patients. Methods This prospective cross-sectional study, conducted at Jaffna Teaching Hospital, Jaffna, Sri Lanka, from July 2022 to June 2023, focused on surgically treated urolithiasis patients. Institutional ethical clearance was obtained. Patient details and investigational findings were collected through questionnaires and data extraction forms. Stone analysis utilized Fourier transform infrared spectroscopy, and a detailed metabolic evaluation of a 24-hour urine collection sample was carried out. Results This study followed 153 surgically treated urolithiasis patients, primarily male (64.3%), with a mean age of 48.64. Ureteric colic (48.4%) was common, with kidney stones (45.8%) prevalent; 57.52% had recurrent stones. Diabetes mellitus (DM; 23.5%) was the top comorbidity. Calcium oxalate monohydrate (COM) stones (78.4%) were the most frequent, followed by uric acid (12.4%). COM predominated in the 40-59 age group. There was no significant gender-stone type association. A total of 86.9% had metabolic abnormalities, notably hypocitraturia (60.1%). Moreover, 23% had both hypocitraturia and hypomagnesuria. Some metabolic disorders showed gender differences, with a marginal age-metabolic disorder association (p < 0.061). Urine oxalate levels were normal, with higher variability in males. Conclusion Middle-aged males with urolithiasis commonly presented with ureteric colic and predominantly had COM stones. Recurrent stones were common, often accompanied by metabolic abnormalities such as hypocitraturia and hypomagnesuria, with DM as the primary comorbidity.

4.
Anat Histol Embryol ; 53(4): e13075, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-38881030

RÉSUMÉ

The gross morphological examination of native caprine heart valves revealed distinctive structural characteristics of the caprine's cardiac anatomy. Four primary orifices were identified, each protected by thin, valve-like structures. Atrioventricular orifices featured tricuspid and bicuspid valves, while the aorta and pulmonary arteries were guarded by semilunar valves. Within the atrioventricular apparatus, distinct features were observed including the tricuspid valve's three leaflets and the bicuspid valve's anterior and posterior leaflets. Ultrasonography provided insights into valve thickness and chordae tendineae lengths. Morphometric studies compared leaflets/cusps within individual native valves, showcasing significant variations in dimensions. Comparative analysis between native and decellularized valves highlighted the effects of decellularization on leaflet thickness and chordae tendineae lengths. Decellularized valves exhibited reduced dimensions compared to native valves, indicating successful removal of cellular components. While some dimensions remained unchanged post-decellularization, significant reductions were observed in leaflet thicknesses and chordae tendineae lengths. Notably, semilunar valve cusps displayed varying responses to decellularization, with significant reductions in cusp lengths observed in the aortic valve, while the pulmonary valve exhibited more subtle changes. These findings underscore the importance of understanding structural alterations in heart valves post-decellularization, providing valuable insights for tissue engineering applications and regenerative medicine.


Sujet(s)
Capra , Valves cardiaques , Animaux , Capra/anatomie et histologie , Valves cardiaques/anatomie et histologie , Valve du tronc pulmonaire/anatomie et histologie , Cordages tendineux/anatomie et histologie , Valve aortique/anatomie et histologie , Valve atrioventriculaire droite/anatomie et histologie , Échographie/médecine vétérinaire , Mâle
5.
Toxics ; 11(2)2023 Feb 14.
Article de Anglais | MEDLINE | ID: mdl-36851051

RÉSUMÉ

Cyanobacterial blooms have been recognized as a problem in fresh water for about 150 years. Over the past 50 years, experimental studies on the subject have gained importance considering the increasing need to control toxic cyanobacterial blooms. This article presents information on the different lines of research that have been undertaken on zooplankton-cyanobacteria interactions over the past 50 years. These include information on filtering/ingestion rates and phytoplankton preferences of small and large rotifers, cladocerans, and copepods; growth rates of zooplankton on cyanobacterial diets; feeding rates of other freshwater invertebrates on cyanobacteria; role of zooplankton in top-down biomanipulation efforts; effect of cyanotoxins on zooplankton; bioaccumulation of cyanotoxins; and physical and chemical control of cyanobacterial blooms. We also highlight measures that have led to successful lake management and improvement of water quality in selected waterbodies.

6.
Int J Surg Case Rep ; 99: 107653, 2022 Oct.
Article de Anglais | MEDLINE | ID: mdl-36115121

RÉSUMÉ

Prostate cancer is one of the most frequent cancers in males and commonly a disease of the older population, but it is increasingly seen among older adolescents and young adults. The common sites of metastasis of prostatic carcinoma are bones and regional lymph nodes. Testicular metastasis from prostatic carcinoma is an infrequent presentation. We report a case of a young patient with prostatic carcinoma and multiple metastases, including bilateral testis. A 40-year-old male presented with lower urinary tract voiding symptoms and back pain for three months. His prostate-specific antigen level was elevated at 13.98 ng/ml. A magnetic resonance imaging of the prostate revealed two PIRADS V lesions and metastases in multiple bones and regional lymph nodes. On follow up, the patient complained of bilateral testicular swelling and ultrasound scan of the testes revealed bilateral testicular metastasis. Fine needle aspiration cytology of right-side testicular lesion revealed malignant cells compatible with metastasis from prostate cancer. Later involvement of multilevel vertebral and skull metastases was identified by magnetic resonance imaging. A T3bN1M1c staging of prostate cancer was made, androgen deprivation therapy followed by chemo and radiotherapy was instituted, following extensive discussion with the patient. Unfortunately the patient succumbed to the illness during the course of treatment. This case report is of a patient with rare presentation of bilateral testicular metastasis with prostate cancer in young age.

7.
Phys Rev Lett ; 128(14): 146601, 2022 Apr 08.
Article de Anglais | MEDLINE | ID: mdl-35476495

RÉSUMÉ

We study many-body localization (MBL) for interacting one-dimensional lattice fermions in random (Anderson) and quasiperiodic (Aubry-Andre) models, focusing on the role of interaction range. We obtain the MBL quantum phase diagrams by calculating the experimentally relevant inverse participation ratio (IPR) at half-filling using exact diagonalization methods and extrapolating to the infinite system size. For short-range interactions, our results produce in the phase diagram a qualitative symmetry between weak and strong interaction limits. For long-range interactions, no such symmetry exists as the strongly interacting system is always many-body localized, independent of the effective disorder strength, and the system is analogous to a pinned Wigner crystal. We obtain various scaling exponents for the IPR, suggesting conditions for different MBL regimes arising from interaction effects.

8.
J Psychiatr Res ; 145: 250-255, 2021 Dec 11.
Article de Anglais | MEDLINE | ID: mdl-34952375

RÉSUMÉ

Although highly effective, electroconvulsive therapy (ECT) often produces cognitive side effects which can be a barrier for patients. Monitoring cognitive side effects during the acute course is therefore recommended to identify patients at increased risk for adverse outcomes. The Brief ECT Cognitive Screen (BECS) is a brief instrument designed to measure emerging cognitive side effects from ECT. The aim of this study was to examine the clinical utility of the BECS for predicting adverse cognitive outcomes in real world clinic settings. The study included data collated from four participating sites in the Clinical Alliance for ECT and Related treatments (CARE) network. The BECS was administered at pre ECT and post 3 or 4 ECT. The primary outcome was a ≥4 point decrease on the Montreal Cognitive Assessment (MoCA) from pretreatment to post ECT. Logistic multiple regression analyses examined the BECS and other relevant clinical and demographic and treatment factors as predictors. The final analysis included 623 patients with diverse indications for ECT including 53.6% with major depression and 33.7% with schizophrenia or schizoaffective disorder. A higher total score on the BECS significantly predicted decline in Total Scores on the MoCA [B = 0.25 (0.08), p = 0.003], though not decline in MoCA Delayed Recall scores (p > 0.1). Other significant predictors included higher pretreatment MoCA Total Scores and female gender for verbal anterograde memory decline. This study confirmed that the BECS has clinical utility for identifying patients with both reduced and increased risk for adverse cognitive outcomes from ECT.

9.
Article de Anglais | MEDLINE | ID: mdl-34762559

RÉSUMÉ

The emerging contaminant 4-nonylphenol is an active ingredient in many surfactants. Though 4-nonylphenol has been reported in Mexican waterbodies, no stringent law is available to establish its permissible limits. Most ecotoxicological assays using zooplankton species are based on previously unexposed populations, and multigenerational experiments are rare. Plationus patulus and Brachionus havanaensis are widely distributed species in Mexico and have been used in ecotoxicological assessments. In this work, the median lethal concentration of 4-nonylphenol (LC50, 24 h) for both rotifer species was derived. Based on our acute toxicity data (24 h LC50 of 4-nonylphenol for P. patulus and B. havanaensis were 500 and 250 µg L-1, respectively), three sublethal concentrations (µg L-1) (7.81, 15.82 and 31.25 for B. havanaensis and 15.62, 31.25 and 62.5 for P. patulus) were used in the life table demography tests for two successive generations (F0 and F1) of either rotifer species. Regardless of the concentrations used, 4-nonylphenol had an adverse effect on both rotifer species over two successive generations. P. patulus was more sensitive than B. havanaensis in chronic toxicity tests. F1 generation of both rotifer species was far more adversely affected than the F0 in all toxicant treatments.


Sujet(s)
Perturbateurs endocriniens , Rotifera , Polluants chimiques de l'eau , Animaux , Démographie , Perturbateurs endocriniens/toxicité , Phénols , Tests de toxicité chronique , Polluants chimiques de l'eau/toxicité
10.
Phys Rev Lett ; 127(6): 067001, 2021 Aug 06.
Article de Anglais | MEDLINE | ID: mdl-34420352

RÉSUMÉ

We show that Floquet chiral topological superconductivity arises naturally in Josephson junctions made of magnetic topological insulator-superconductor sandwich structures. The Josephson phase modulation associated with an applied bias voltage across the junction drives the system into the anomalous Floquet chiral topological superconductor hosting chiral Majorana edge modes in the quasienergy spectrum, with the bulk Floquet bands carrying zero Chern numbers. The bias voltage acts as a tuning parameter enabling novel Floquet topological quantum phase transitions driving the system into a myriad of exotic Majorana-carrying Floquet topological superconducting phases. Our theory establishes a new paradigm for realizing Floquet chiral topological superconductivity in solid-state systems, which should be experimentally directly accessible.

11.
Phys Rev Lett ; 126(13): 137001, 2021 Apr 02.
Article de Anglais | MEDLINE | ID: mdl-33861104

RÉSUMÉ

We establish quasi-two-dimensional thin films of iron-based superconductors (FeSCs) as a new high-temperature platform for hosting intrinsic time-reversal-invariant helical topological superconductivity (TSC). Based on the combination of Dirac surface state and bulk extended s-wave pairing, our theory should be directly applicable to a large class of experimentally established FeSCs, opening a new TSC paradigm. In particular, an applied electric field serves as a "topological switch" for helical Majorana edge modes in FeSC thin films, allowing for an experimentally feasible design of gate-controlled helical Majorana circuits. Applying an in-plane magnetic field drives the helical TSC phase into a higher-order TSC carrying corner-localized Majorana zero modes. Our proposal should enable the experimental realization of helical Majorana fermions.

13.
Phys Rev Lett ; 126(3): 036803, 2021 Jan 22.
Article de Anglais | MEDLINE | ID: mdl-33543971

RÉSUMÉ

Inspired by the rich physics of twisted 2D bilayer moiré systems, we study Coulomb interacting systems subjected to two overlapping finite 1D lattice potentials of unequal periods through exact numerical diagonalization. Unmatching underlying lattice periods lead to a 1D bichromatic "moiré" superlattice with a large unit cell and consequently a strongly flattened band, exponentially enhancing the effective dimensionless electron-electron interaction strength and manifesting clear signatures of enhanced Mott gaps at discrete fillings. An important nonperturbative finding is a remarkable fine-tuning effect of the precise lattice commensuration, where slight variations in the relative lattice periods may lead to a suppression of the correlated insulating phase, in qualitative agreement with the observed fragility of the correlated insulating phase in twisted bilayer graphene. Our predictions, which should be directly verifiable in bichromatic optical lattices, establish that the competition between interaction and incommensuration is a key element of the physics of moiré superlattices.

14.
J Therm Biol ; 94: 102752, 2020 Dec.
Article de Anglais | MEDLINE | ID: mdl-33292993

RÉSUMÉ

Diurnal temperature fluctuations affect ectothermic species more than endothermic taxa. We tested the effect of three fixed temperatures (20, 25 and 30 °C) and a 24 h variable (20-30 °C) on the population growth and fatty acid profiles of the common rotifer Brachionus calyciflorus. Depending on the temperature treatment, the peak population abundances of B. calyciflorus varied from 65 to 80 ind./ml, the lowest being on variable temperature range. The rate of population increase varied from 0.31 to 0.52 per day, highest being at 30 °C. There was a curvilinear relationship between the population density and the egg ratio (number of eggs/female) in all the tested temperature regimes. The egg ratio was higher (>0.6) for treatments involving fixed temperatures, but for variable temperature regime, the egg ratios were lower (<0.5). Temperature also induced changes in the fatty acid content of B. calyciflorus. While the total saturated fatty acids increased, both mono-unsaturated and poly-unsaturated fatty acids decreased with increasing temperature regime. These results have been interpreted in relation to the role of temperature (both intensity and mode of exposure) on the population growth characteristics of rotifers.


Sujet(s)
Acides gras/métabolisme , Rotifera/métabolisme , Température , Animaux , Femelle , Ovule , Densité de population
15.
Case Rep Urol ; 2020: 8858606, 2020.
Article de Anglais | MEDLINE | ID: mdl-33299634

RÉSUMÉ

Torsion of epididymal cyst (EC) is an exceedingly rare cause of acute scrotum in both children and adults. We add our case as the ninth case to literature which was an 8-year-old child presented with features of acute scrotum with history of EC on conservative management. Doppler sonography showed perfused normal bilateral testes and a 4.1 × 1.7 cm septate cystic lesion of right epididymis. On scrotal exploration, we found a haemorrhagic cystic lesion attached to the upper pole of right testis and twisted for 540 degrees with normal testis and appendage. Cyst was excised, and histopathology revealed a haemorrhagic EC. Our case was peculiar due to, presenting as acute scrotum in a child of 1-10 years age group who was conservatively managed for right-sided EC and presence of 540 degrees torsion.

16.
Environ Toxicol Chem ; 39(12): 2409-2419, 2020 12.
Article de Anglais | MEDLINE | ID: mdl-32926578

RÉSUMÉ

Many urban lakes in Mexico City such as Lake Chapultepec are infested with high densities of cyanobacteria, particularly Microcystis. We tested the effect of cyanotoxins from cyanobacterial crude extracts on the demographic variables of zooplankton. The rotifers Brachionus havanaensis and Brachionus calyciflorus, and the cladocerans Ceriodaphnia dubia and Moina macrocopa were used for the assays. Temperature effects on the response of B. calyciflorus and 2 clones of M. macrocopa were tested. We hypothesized that with an increase in cyanotoxin concentration and temperature there would be an increase in the adverse effect on the test species and that the clone of Moina previously exposed to cyanobacteria from Lake Chapultepec would be more resistant to the cyanotoxins. Demography experiments showed that B. havanaensis was more sensitive than C. dubia. The negative effect of the cyanobacterial crude extract on B. calyciflorus was greater at 30 °C than at 20 °C or 25 °C. The strain of M. macrocopa isolated from Lake Chapultepec was more resistant to the cyanotoxins than the strain that had not been previously exposed to the cyanobacteria. The present study indicated that cyanobacteria in Lake Chapultepec are highly toxic and, considering the recreational use of this lake, should be controlled. Environ Toxicol Chem 2020;39:2409-2419. © 2020 SETAC.


Sujet(s)
Mélanges complexes/toxicité , Cyanobactéries/composition chimique , Lacs/composition chimique , Microcystines/toxicité , Polluants chimiques de l'eau/toxicité , Zooplancton/effets des médicaments et des substances chimiques , Animaux , Cladocera/effets des médicaments et des substances chimiques , Écotoxicologie , Mexique , Rotifera/effets des médicaments et des substances chimiques , Spécificité d'espèce , Facteurs temps
17.
Soc Sci Med ; 264: 113310, 2020 11.
Article de Anglais | MEDLINE | ID: mdl-32877846

RÉSUMÉ

Team-based primary care offers a wide range of health services to patients by using interdisciplinary health care providers committed to delivering comprehensive, coordinated and high-quality care through team collaboration. Ontario's Family Health Team (FHT), the largest team-based practice model in Canada, was introduced to improve access to and effectiveness of primary health care services, and was available primarily for physicians paid under blended capitation models (Family Health Organizations and Family Health Networks). Using health administrative data on physicians practicing under blended capitation models in Ontario between 2006 and 2015, we study the impact of switching from non-FHT to FHTs on the production of capitated comprehensive care services, after-hours services, non-incentivized services, and services provided to non-enrolled patients by family physicians. We find that when in FHTs, physicians increase the production of total services and non-incentivized services by 26% and 5% per annum and reduce capitated comprehensive care services by 3.2% per annum. When in FHTs, physicians also see and enroll more patients relative to those practicing in non-FHTs. We find evidence of improved access to physician's services under team-based primary care, but switching to FHTs has no effect on the production of after-hours services and services provided to non-enrolled patients.


Sujet(s)
Santé de la famille , Équipe soignante , Humains , Ontario , Médecins de famille , Soins de santé primaires
18.
Mar Pollut Bull ; 157: 111341, 2020 Aug.
Article de Anglais | MEDLINE | ID: mdl-32658699

RÉSUMÉ

Several abiotic factors influence the ecological responses of aquatic invertebrates to metal toxicity. We examined the effect of salinity (10, 20, and 30 psu) and temperature (25 and 32 °C) on acute and chronic arsenic (As) toxicity to the euryhaline rotifers, Proales similis and Brachionus ibericus. In general, higher salinities and low temperature resulted in lower arsenic toxicity. The population growth studies indicated that P. similis was more sensitive than B. ibericus to As. Arsenic toxicity intensified the vulnerability of P. similis to B. ibericus competition. Life table parameters decreased with increasing As levels in the medium. Chronic toxicity bioassays were more sensitive than acute toxicity tests for determining the adverse effect of As to rotifers. Our findings provide useful insights on the effect of arsenic on rotifer populations exposed to different temperature and salinity scenarios. Proales similis could be an important complement to brachionid rotifers for marine toxicity bioassays.


Sujet(s)
Arsenic , Rotifera , Polluants chimiques de l'eau , Animaux , Salinité , Température
20.
Phys Rev Lett ; 124(13): 136407, 2020 Apr 03.
Article de Anglais | MEDLINE | ID: mdl-32302172

RÉSUMÉ

We propose MnBi_{2n}Te_{3n+1} as a magnetically tunable platform for realizing various symmetry-protected higher-order topology. Its canted antiferromagnetic phase can host exotic topological surface states with a Möbius twist that are protected by nonsymmorphic symmetry. Moreover, opposite surfaces hosting Möbius fermions are connected by one-dimensional chiral hinge modes, which offers the first material candidate of a higher-order topological Möbius insulator. We uncover a general mechanism to feasibly induce this exotic physics by applying a small in-plane magnetic field to the antiferromagnetic topological insulating phase of MnBi_{2n}Te_{3n+1}, as well as other proposed axion insulators. For other magnetic configurations, two classes of inversion-protected higher-order topological phases are ubiquitous in this system, which both manifest gapped surfaces and gapless chiral hinge modes. We systematically discuss their classification, microscopic mechanisms, and experimental signatures. Remarkably, the magnetic-field-induced transition between distinct chiral hinge mode configurations provides an effective "topological magnetic switch".

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