•The state dependency of the neurovascular coupling was reflected by distinctive patterns of the EEG-fMRI spectra correspondence between task and resting conditions.•In the eye-open-eye-close (EOEC) ...task, a phase-amplitude coupling (PAC) was found between EEG alpha-band oscillations and the low-frequency fMRI signals in the visual area.•In the resting state, an amplitude-amplitude coupling (AAC) was demonstrated between gamma-band of EEG-Oz and the high-frequency fMRI signals (0.15–0.25 Hz) in the visual network.•Based on the hilbert-huang transform (HHT), the EEG-fMRI coupling was carried out for both PAC and AAC, exhibiting different sensitivity features between PAC/AAC spectral correspondence maps.
Neurovascular coupling serves as an essential neurophysiological mechanism in functional neuroimaging, which is generally presumed to be robust and invariant across different physiological states, encompassing both task engagement and resting state. Nevertheless, emerging evidence suggests that neurovascular coupling may exhibit state dependency, even in normal human participants. To investigate this premise, we analyzed the cross-frequency spectral correspondence between concurrently recorded electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) data, utilizing them as proxies for neurovascular coupling during the two conditions: an eye-open-eye-close (EOEC) task and a resting state. We hypothesized that given the state dependency of neurovascular coupling, EEG-fMRI spectral correspondences would change between the two conditions in the visual system. During the EOEC task, we observed a negative phase-amplitude-coupling (PAC) between EEG alpha-band and fMRI visual activity. Conversely, in the resting state, a pronounced amplitude-amplitude-coupling (AAC) emerged between EEG and fMRI signals, as evidenced by the spectral correspondence between the EEG gamma-band of the midline occipital channel (Oz) and the high-frequency fMRI signals (0.15–0.25 Hz) in the visual network. This study reveals distinct scenarios of EEG-fMRI spectral correspondence in healthy participants, corroborating the state-dependent nature of neurovascular coupling.
We explored the macro-scale neurovascular coupling via the spectral correspondence of concurrent EEG-fMRI signals in a resting-state condition and a eye-open-eye-close (EOEC) task. By decomposing time-frequency maps for both signals, we revealed the EEG-fMRI spectral coupling through the temporal correlations at different frequency bands in the resting state, as compared with those in the EOEC task. Display omitted
Ovulation is dependent upon numerous factors mediating follicular growth, vascularization, and ultimately oocyte release via follicle rupture. Endothelin-2 (EDN2) is a potent vasoconstrictor that is ...transiently produced prior to follicle rupture by granulosa cells of periovulatory follicles and induces ovarian contraction. To determine the role of Edn2 expression, surgical transplant and novel conditional knockout mice were super-ovulated and analyzed. Conditional knockout mice utilized a new iCre driven by the Esr2 promoter to selectively remove Edn2. Follicle rupture and fertility were significantly impaired in the absence of ovarian Edn2 expression. When ovaries of Edn2KO mice were transplanted in wild type recipients, significantly more corpora lutea containing un-ovulated oocytes were present after hormonal stimulation (1.0 vs. 5.4, p = 0.010). Following selective ablation of Edn2 in granulosa cells, Esr2-Edn2KO dams had reduced oocytes ovulated (3.8 vs. 16.4 oocytes/ovary) and smaller litters (4.29 ± l.02 vs. 8.50 pups/dam). However, the number of pregnancies per pairing was not different and the reproductive axis remained intact. Esr2-Edn2KO ovaries had a higher percentage of antral follicles and fewer corpora lutea; follicles progressed to the antral stage but many were unable to rupture. Conditional loss of endothelin receptor A in granulosa cells also decreased ovulation but did not affect fecundity. These data demonstrate that EDN2-induced intraovarian contraction is a critical trigger of normal ovulation and subsequent fecundity.
Endocrine disrupting chemicals (EDCs) in the environment are considered to be a contributing factor to the decline in the sperm quality. With growing evidence of the harmful effects of EDCs on the ...male reproductive system, we tested the hypothesis that prenatal exposure to an environmentally relevant phthalate mixture adversely affects reproductive outcomes and androgen synthesis. In this study, an environmentally relevant composition of phthalates (15% DiNP, 21% DEHP, 36% DEP, 15% DBP, 8% DiBP, and 5% BBzP) that were detected in urine samples of pregnant women in Illinois, United States, was used. Pregnant CD-1 mice (F0) were orally dosed with a vehicle or the phthalate mixtures (20 µg/kg/day, 200 µg/kg/day, 200 mg/kg/day, or 500 mg/kg/day) from gestational day 10.5 to the day of birth. Then, the indices of the reproductive function of the F1 males born to these dams were assessed. Those male mice prenatally exposed to the phthalate mixture had smaller gonads, prostates and seminal vesicles, especially in the 20 µg/kg/day and 500 mg/kg/day phthalate mixture groups, compared to the controls. Importantly, at the age of 12 months, those prenatally exposed mice had significantly lower serum testosterone concentrations accompanied by the decreased mRNA expression of testicular steroidogenic genes (StAR, Cyp11, and Cyp17) and impaired spermatogenesis. Taken together, this study found that prenatal exposure to environmentally relevant doses of a phthalate mixture caused a life-long impact on the reproduction in male mice.
•Prenatal exposure to an environmentally relevant doses of phthalate mixture adversely affects androgen synthesis and downregulates the testicular steroidogenic genes expression.•Prenatally exposed mice had significantly lower sperm concentration and impaired spermatogenesis.•Prenatal exposure to phthalate mixture caused a life-long impact on the reproduction in male mice.
A longer duration of untreated psychosis (DUP) has been associated with poor clinical outcomes in patients with schizophrenia (SZ); however, it remains unclear whether this is due to neurotoxic ...effects of psychosis. The purpose of this study was to use near-infrared spectroscopy (NIRS) to investigate the influence of DUP on brain function using two verbal fluency tests (VFTs) in patients with first-episode SZ (FES). A total of 28 FES patients and 29 healthy controls (HC) underwent NIRS during VFTs. Group comparisons of cortical activity were made using two-tailed t-tests and the false discovery rate method. We then examined the associations between DUP and hemodynamic changes in each channel to identify any effects of DUP on brain cortical activity. During the letter VFT, the HC group exhibited significantly greater cortical activations over bilateral frontotemporal regions compared to FES patients. However, this distinction was not observed while performing a category version of the VFT. In addition, no associations between DUP and brain cortical activity were observed in the FES group during either VFT. In conclusion, we did not find an association between DUP and frontotemporal cortical activities. This might be because neurodevelopmental disturbances result in neurocognitive deficits long before psychotic symptoms onset.
Significance In the human brain, from early in development through to adulthood, the superior temporal sulcus is deeper in the right than the left cerebral hemisphere in the area ventral of Heschl’s ...gyrus. Irrespective of gender, handedness, and language lateralization, and present in several pathologies, this asymmetry is widely shared among the human population. Its appearance early in life suggests strong genetic control over this part of the brain. In contrast, the asymmetry is barely visible in chimpanzees. Thus this asymmetry probably is a key locus to look for variations in gene expression among the primate lineage that have favored the evolution of crucial cognitive abilities sustained by this sulcus in our species, namely communication and social cognition.
Identifying potentially unique features of the human cerebral cortex is a first step to understanding how evolution has shaped the brain in our species. By analyzing MR images obtained from 177 humans and 73 chimpanzees, we observed a human-specific asymmetry in the superior temporal sulcus at the heart of the communication regions and which we have named the “superior temporal asymmetrical pit” (STAP). This 45-mm-long segment ventral to Heschl’s gyrus is deeper in the right hemisphere than in the left in 95% of typical human subjects, from infanthood till adulthood, and is present, irrespective of handedness, language lateralization, and sex although it is greater in males than in females. The STAP also is seen in several groups of atypical subjects including persons with situs inversus, autistic spectrum disorder, Turner syndrome, and corpus callosum agenesis. It is explained in part by the larger number of sulcal interruptions in the left than in the right hemisphere. Its early presence in the infants of this study as well as in fetuses and premature infants suggests a strong genetic influence. Because this asymmetry is barely visible in chimpanzees, we recommend the STAP region during midgestation as an important phenotype to investigate asymmetrical variations of gene expression among the primate lineage. This genetic target may provide important insights regarding the evolution of the crucial cognitive abilities sustained by this sulcus in our species, namely communication and social cognition.
This study used a three-dimensional (3D) printing process to develop the Ag/AgCl/TiO
2
coupled photocatalyst with a specific surface area of 748 mm
2
/g. We examined the catalytic capability of this ...photocatalyst in degrading methyl blue (MB) dye and sterilizing
Escherichia coli
as well as the durability and reliability of its continuous use. A TiO
2
module was constructed through fused filament fabrication (FFF), and the adopted 3D printing filament was composed of anatase TiO
2
nanoparticles, stearic acid, wax, and a plasticizer. The green compact of the TiO
2
module was subjected to solvent debinding, thermal debinding, and sintering to obtain a fundamental structure that was subsequently coupled with AgCl through a precipitation reaction. Ultraviolet radiation was used for the photoreduction to obtain the Ag/AgCl/TiO
2
coupled photocatalyst coupling module. This photocatalyst can effectively degrade MB dye and disinfect
E. coli
. The degradation of MB dye and sterilization of
E. coli
were conducted under visible and ultraviolet light. The degradation of MB dye by the Ag/AgCl/TiO
2
coupled photocatalyst was a first-order reaction. In addition, this coupled photocatalyst could retain its MB dye degradation rate (95%) for five cycles.
E. coli
was sterilized using the prepared photocatalytic module in a 120-min test, and this sterilization phenomenon could be presented as a hyperbolic reaction. The photocatalytic module manufactured in this study through FFF could efficiently degrade pollutants in water, and its durability and reliability after repeated use have been approved.
Severe asymptomatic carotid stenosis has been associated with cognitive impairment, but it is unknown whether this association is attributable to effects on brain connectivity. We present cognitive ...network abnormalities in a group of patients at a presymptomatic stage.
Seventeen patients with ≥ 70% asymptomatic stenosis of unilateral internal carotid artery were compared with 26 healthy controls utilizing a comprehensive neuropsychological battery, the dizziness handicap inventory, and multimodality neuroimaging including diffusion tensor imaging and resting-state functional connectivity magnetic resonance imaging. Longitudinally, assessments were completed in a subgroup of 10 patients at 3 months after carotid artery stenting.
Compared with the healthy controls, the patients had worse dizziness scores, poorer memory, complex visuo-spatial performances, and lower whole-brain mean fractional anisotropy. The Scheltens scores of leukoaraiosis/infarction were not different between groups. Their seed-based functional connectivity magnetic resonance imaging showed marked decrements of interhemispheric and intrahemispheric, ipsilaterally to carotid stenosis, functional connectivity in the frontoparietal network. In the default mode network, the intrahemispheric functional connectivity was bilaterally impaired. Importantly, the disrupted mean fractional anisotropy in the patients significantly correlated with the attention and verbal memory functions. After successful carotid artery stenting, small but measurable increments of the mean fractional anisotropy and little functional connectivity in the default mode network ipsilateral-to-carotid artery stenting were noted.
We identified for the first time distinct patterns of network disruption that correlate with cognitive fragility in patients with asymptomatic carotid stenosis. Brain connectivity may provide early and useful biomarkers for brain ischemia and reperfusion.
Reliable mapping of system-level individual differences is a critical first step toward precision medicine for complex disorders such as schizophrenia. Disrupted structural covariance indicates a ...system-level brain maturational disruption in schizophrenia. However, most studies examine structural covariance at the group level. This prevents subject-level inferences. Here, we introduce a Network Template Perturbation approach to construct individual differential structural covariance network (IDSCN) using regional gray-matter volume. IDSCN quantifies how structural covariance between two nodes in a patient deviates from the normative covariance in healthy subjects. We analyzed T1 images from 1287 subjects, including 107 first-episode (drug-naive) patients and 71 controls in the discovery datasets and established robustness in 213 first-episode (drug-naive), 294 chronic, 99 clinical high-risk patients, and 494 controls from the replication datasets. Patients with schizophrenia were highly variable in their altered structural covariance edges; the number of altered edges was related to severity of hallucinations. Despite this variability, a subset of covariance edges, including the left hippocampus-bilateral putamen/globus pallidus edges, clustered patients into two distinct subgroups with opposing changes in covariance compared to controls, and significant differences in their anxiety and depression scores. These subgroup differences were stable across all seven datasets with meaningful genetic associations and functional annotation for the affected edges. We conclude that the underlying physiology of affective symptoms in schizophrenia involves the hippocampus and putamen/pallidum, predates disease onset, and is sufficiently consistent to resolve morphological heterogeneity throughout the illness course. The two schizophrenia subgroups identified thus have implications for the nosology and clinical treatment.
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