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1.
Ultrasound Med Biol ; 49(8): 1852-1860, 2023 08.
Article in English | MEDLINE | ID: mdl-37246049

ABSTRACT

OBJECTIVE: The objective of this work was to study microbubble-enhanced temperature elevation with high-intensity focused ultrasound (HIFU) at different acoustic pressures and under image guidance. The microbubbles were administered with either local or vascular injections (that mimic systemic injections) in perfused and non-perfused ex vivo porcine liver under ultrasound image guidance. METHODS: Porcine liver was insonified for 30 s with a single-element HIFU transducer (0.9 MHz, 0.413 ms, 82% duty cycle, focal pressures of 0.6-3.5 MPa). Contrast microbubbles were injected either locally or through the vasculature. A needle thermocouple at the focus measured temperature elevation. Diagnostic ultrasound (Philips iU22, C5-1 probe) guided placement of the thermocouple and delivery of microbubbles and monitored the procedure in real time. RESULTS: At lower acoustic pressures (0.6 and 1.2 MPa) in non-perfused liver, inertial cavitation of the injected microbubbles led to greater temperatures at the focus compared with HIFU-only treatments. At higher pressures (2.4 and 3.5 MPa) native inertial cavitation in the tissue (without injecting microbubbles) resulted in temperature elevations similar to those after injecting microbubbles. The heated area was larger when using microbubbles at all pressures. In the presence of perfusion, only local injections provided a sufficiently high concentration of microbubbles necessary for significant temperature enhancement. CONCLUSION: Local injections of microbubbles provide a higher concentration of microbubbles in a smaller area, avoiding acoustic shadowing, and can lead to higher temperature elevation at lower pressures and increase the size of the heated area at all pressures.


Subject(s)
High-Intensity Focused Ultrasound Ablation , Hyperthermia, Induced , Animals , Swine , Microbubbles , Contrast Media , Ultrasonography , Liver/diagnostic imaging , Liver/surgery , Hyperthermia, Induced/methods , High-Intensity Focused Ultrasound Ablation/methods
2.
Physiol Behav ; 254: 113884, 2022 10 01.
Article in English | MEDLINE | ID: mdl-35718217

ABSTRACT

Here we use the glucocorticoid cascade hypothesis framework to address the role of baseline cortisol on changes in cognitive function over a 3-year span in non-demented rural Americans. We also determine if genotype at 4 different single nucleotide polymorphisms (SNPs) relates to change in cognitive function. We predicted 1) over time, increases in baseline cortisol will be associated with decline in cognitive function, 2) individuals homozygous for 3 CRFR1 SNP rare alleles (AA rs110402, TT rs7209436, and TT rs242924 vs. others) will show less cognitive decline and this will be particularly pronounced in those with lower baseline cortisol, and 3) FKBP5 T carriers (TT or CT vs. CC homozygotes) will have decreased cognitive performance and this will be particularly pronounced in individuals with higher baseline cortisol. Collectively, our data do not robustly support the glucocorticoid cascade hypothesis. In several cases, higher baseline cortisol related to better cognitive performance over time, but within individuals, increased cortisol over time related to decreased performance on some cognitive domains over time. Contrary to our predictions, individuals with the rare CRFR1 haplotype (AA, TT, TT) performed worse than individuals with the common haplotype across multiple domains of cognitive function. FKBP5 genotype status had minimal impacts on cognitive outcomes. Genotype effects were largely not dependent on cortisol. The Project FRONTIER dataset is supported by Texas Tech University Health Sciences Center Garrison Institute on Aging.


Subject(s)
Glucocorticoids , Hydrocortisone , Aging , Cognition , Genotype , Humans , Polymorphism, Single Nucleotide/genetics , Receptors, Corticotropin-Releasing Hormone , Tacrolimus Binding Proteins/genetics
3.
Environ Pollut ; 254(Pt A): 112977, 2019 Nov.
Article in English | MEDLINE | ID: mdl-31377326

ABSTRACT

Glyphosate, as a broad-spectrum herbicide, is frequently detected in water and several studies have investigated its effects on several freshwater aquatic organisms. Yet, only few investigations have been performed on marine macroalgae. Here, we studied both the metabolomics responses and the effect on primary production in the endemic brown algae Fucus virsoides exposed to different concentration (0, 0.5, 1.5 and 2.5 mg L-1) of a commercial glyphosate-based herbicide, namely Roundup®. Our results show that Roundup® significantly reduced quantum yield of photosynthesis (Fv/Fm) and caused alteration in the metabolomic profiles of exposed thalli compared to controls. Together with the decrease in the aromatic amino acids (phenylalanine and tyrosine), an increase in shikimate content was detected. The branched-amino acids differently varied according to levels of herbicide exposure, as well as observed for the content of choline, formate, glucose, malonate and fumarate. Our results suggest that marine primary producers could be largely affected by the agricultural land use, this asking for further studies addressing the ecosystem-level effects of glyphosate-based herbicides in coastal waters.


Subject(s)
Fucus/metabolism , Glycine/analogs & derivatives , Herbicides/toxicity , Water Pollutants, Chemical/toxicity , Agriculture , Animals , Ecosystem , Fresh Water/chemistry , Glycine/toxicity , Metabolomics , Phenylalanine/metabolism , Photosynthesis/drug effects , Shikimic Acid/metabolism , Tyrosine/metabolism , Glyphosate
4.
Neurobiol Stress ; 10: 100154, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30949563

ABSTRACT

The neurophysiological underpinnings involved in susceptibility to and maintenance of anxiety are not entirely known. However, two stress-responsive systems, the hypothalamic-pituitary-adrenal axis and the endocannabinoid system, may interact in anxiety. Here, we examine the relationship between FAAH genotype, CRFR1 genotype, baseline cortisol, and state anxiety in a rural adult population using data from Project FRONTIER. We predicted that FAAH A (AA and AC vs CC; rs324420) and three CRFR1 SNP minor alleles (rs7209436 C→ T [minor allele]; rs110402, G → A [minor]; and rs242924 G→ T [minor]), would interact to predict low baseline cortisol and low state anxiety scores. We found partial support for our prediction. In CRFR1 minor carriers, the FAAH AA or AC (vs. CC) genotype was associated with higher cortisol and with lower anxiety. In CRFR1 non-minors, those with FAAH AA or AC (vs. CC) showed decreased cortisol and higher anxiety. These results suggest that FAAH CC genotype only conveys risk for anxiety in individuals who are also carriers of the CRFR1 minor combination. FAAH genotype was significantly associated with baseline cortisol but was not independently associated with anxiety. Contrary to our predictions, baseline cortisol was negatively associated with anxiety. Lastly, we did not find any independent relationships between any of our SNPs and baseline cortisol or anxiety. These data suggest FAAH and cortisol interact to predict state anxiety, but that the relationship depends on CRFR1 genotype. The Project FRONTIER dataset is supported by Texas Tech University Health Sciences Center Garrison Institute on Aging.

5.
Optom Vis Sci ; 95(4): 323-331, 2018 04.
Article in English | MEDLINE | ID: mdl-29561501

ABSTRACT

SIGNIFICANCE: We investigated links between the intrinsically photosensitive retinal ganglion cells, light exposure, refractive error, and sleep. Results showed that morning melatonin was associated with light exposure, with modest differences in sleep quality between myopes and emmetropes. Findings suggest a complex relationship between light exposure and these physiological processes. PURPOSE: Intrinsically photosensitive retinal ganglion cells (ipRGCs) signal environmental light, with pathways to the midbrain to control pupil size and circadian rhythm. Evidence suggests that light exposure plays a role in refractive error development. Our goal was to investigate links between light exposure, ipRGCs, refractive error, and sleep. METHODS: Fifty subjects, aged 17-40, participated (19 emmetropes and 31 myopes). A subset of subjects (n = 24) wore an Actiwatch Spectrum for 1 week. The Pittsburgh Sleep Quality Index (PSQI) was administered, and saliva samples were collected for melatonin analysis. The post-illumination pupil response (PIPR) to 1 s and 5 s long- and short-wavelength stimuli was measured. Pupil metrics included the 6 s and 30 s PIPR and early and late area under the curve. RESULTS: Subjects spent 104.8 ± 46.6 min outdoors per day over the previous week. Morning melatonin concentration (6.9 ± 3.5 pg/ml) was significantly associated with time outdoors and objectively measured light exposure (P = .01 and .002, respectively). Pupil metrics were not significantly associated with light exposure or refractive error. PSQI scores indicated good sleep quality for emmetropes (score 4.2 ± 2.3) and poor sleep quality for myopes (5.6 ± 2.2, P = .04). CONCLUSIONS: We found that light exposure and time outdoors influenced morning melatonin concentration. No differences in melatonin or the ipRGC-driven pupil response were observed between refractive error groups, although myopes exhibited poor sleep quality compared to emmetropes. Findings suggest that a complex relationship between light exposure, ipRGCs, refractive error, and sleep exists.


Subject(s)
Light , Myopia/physiopathology , Pupil/physiology , Retinal Ganglion Cells/radiation effects , Sleep/physiology , Adolescent , Adult , Female , Humans , Male , Melatonin/metabolism , Photic Stimulation , Retinal Ganglion Cells/metabolism , Saliva/metabolism , Young Adult
6.
Can J Microbiol ; 63(10): 851-856, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28772085

ABSTRACT

Natural transformation is the acquisition of new genetic material via the uptake of exogenous DNA by competent bacteria. Acinetobacter baylyi is model for natural transformation. Here we focus on the natural transformation of A. baylyi ATCC 33305 grown in complex media and seek environmental conditions that appreciably affect transformation efficiency. We find that the transformation efficiency for A. baylyi is a resilient characteristic that remains high under most conditions tested. We do find several distinct conditions that alter natural transformation efficiency including addition of succinate, Fe2+ (ferrous) iron chelation, and substitution of sodium ions with potassium ones. These distinct conditions could be useful to fine tune transformation efficiency for researchers using A. baylyi as a model organism to study natural transformation.


Subject(s)
Acinetobacter/drug effects , Cations, Monovalent/pharmacology , Iron Chelating Agents/pharmacology , Succinic Acid/pharmacology , Transformation, Bacterial/drug effects , Acinetobacter/genetics , Acinetobacter/growth & development , Culture Media
7.
Ophthalmic Physiol Opt ; 37(4): 440-450, 2017 07.
Article in English | MEDLINE | ID: mdl-28656675

ABSTRACT

PURPOSE: Exposure to increasing amounts of artificial light during the night may contribute to the high prevalence of reported sleep dysfunction. Release of the sleep hormone melatonin is mediated by the intrinsically photosensitive retinal ganglion cells (ipRGCs). This study sought to investigate whether melatonin level and sleep quality can be modulated by decreasing night-time input to the ipRGCs. METHODS: Subjects (ages 17-42, n = 21) wore short wavelength-blocking glasses prior to bedtime for 2 weeks. The ipRGC-mediated post illumination pupil response was measured before and after the experimental period. Stimulation was presented with a ganzfeld stimulator, including one-second and five-seconds of long and short wavelength light, and the pupil was imaged with an infrared camera. Pupil diameter was measured before, during and for 60 s following stimulation, and the six-second and 30 s post illumination pupil response and area under the curve following light offset were determined. Subjects wore an actigraph device for objective measurements of activity, light exposure, and sleep. Saliva samples were collected to assess melatonin content. The Pittsburgh Sleep Quality Index (PSQI) was administered to assess subjective sleep quality. RESULTS: Subjects wore the blue-blocking glasses 3:57 ± 1:03 h each night. After the experimental period, the pupil showed a slower redilation phase, resulting in a significantly increased 30 s post illumination pupil response to one-second short wavelength light, and decreased area under the curve for one and five-second short wavelength light, when measured at the same time of day as baseline. Night time melatonin increased from 16.1 ± 7.5 pg mL-1 to 25.5 ± 10.7 pg mL-1 (P < 0.01). Objectively measured sleep duration increased 24 min, from 408.7 ± 44.9 to 431.5 ± 42.9 min (P < 0.001). Mean PSQI score improved from 5.6 ± 2.9 to 3.0 ± 2.2. CONCLUSIONS: The use of short wavelength-blocking glasses at night increased subjectively measured sleep quality and objectively measured melatonin levels and sleep duration, presumably as a result of decreased night-time stimulation of ipRGCs. Alterations in the ipRGC-driven pupil response suggest a shift in circadian phase. Results suggest that minimising short wavelength light following sunset may help in regulating sleep patterns.


Subject(s)
Circadian Rhythm/physiology , Pupil/physiology , Retinal Ganglion Cells/physiology , Sleep/physiology , Actigraphy , Adolescent , Adult , Female , Humans , Male , Melatonin/metabolism , Photic Stimulation , Saliva/metabolism , Time Factors , Young Adult
8.
Sci Rep ; 6: 19642, 2016 Jan 21.
Article in English | MEDLINE | ID: mdl-26791421

ABSTRACT

Coralline red algae are significant components of sea bottom and up to now considered as exclusively marine species. Here we present the first coralline alga from a freshwater environment, found in the Cetina River (Adriatic Sea watershed). The alga is fully adapted to freshwater, as attested by reproductive structures, sporelings, and an inability to survive brackish conditions. Morphological and molecular phylogenetic analyses reveal the species belongs to Pneophyllum and is described as P. cetinaensis sp. nov. The marine-freshwater transition most probably occurred during the last glaciation. The brackish-water ancestor was preadapted to osmotic stress and rapid changes in water salinity and temperature. The particular characteristics of the karst Cetina River, such as hard water enriched with dissolved calcium carbonate and a pH similar to the marine environment, favoured colonization of the river by a marine species. The upstream advance and dispersal is facilitated by exceptionally pronounced zoochory by freshwater gastropods. Pneophyllum cetinaensis defies the paradigm of Corallinales as an exclusively marine group.


Subject(s)
Ecosystem , Fresh Water , Rhodophyta , Genes, Bacterial , Phylogeny , Rhodophyta/classification , Rhodophyta/genetics , Rhodophyta/ultrastructure , Spores, Bacterial
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