Miracle-dz/UniFAR-FTUs huggingface dataset:
Comparison of Matching Pursuit Algorithm with Other Signal Processing Techniques for Computation of the Time-Frequency Power Spectrum of Brain Signals

Signals recorded from the brain often show rhythmic patterns at different frequencies, which are tightly coupled to the external stimuli as well as the internal state of the subject. In addition, these signals have very transient structures related to spiking or sudden onset of a stimulus, which have durations not exceeding tens of milliseconds. Further, brain signals are highly nonstationary because both behavioral state and external stimuli can change on a short time scale. It is therefore essential to study brain signals using techniques that can represent both rhythmic and transient components of the signal, something not always possible using standard signal processing techniques such as short time fourier transform, multitaper method, wavelet transform, or Hilbert transform. In this review, we describe a multiscale decomposition technique based on an over-complete dictionary called matching pursuit (MP), and show that it is able to capture both a sharp stimulus-onset transient and a sustained gamma rhythm in local field potential recorded from the primary visual cortex. We compare the performance of MP with other techniques and discuss its advantages and limitations. Data and codes for generating all time-frequency power spectra are provided.
Collagen nanofiber containing silver nanoparticles for improved wound-healing applications

Abstract Electrospun nanofibers showing great promise for fabricating nanostructured materials might help to improve the quality of wound care. The present study aimed to investigate the wound-healing potential of collagen nanofiber mats containing silver nanoparticles. Silver nanoparticles (AgNPs) synthesized by the chemical reduction method were incorporated in collagen nanofibers during the electrospinning process. Characterization of electrospun nanofiber mats revealed a mean fiber diameters in the range of 300–700 nm with a sustained release of silver ions shown to follow pseudo-order kinetics. MIC of AgNPs against Staphylococcus aureus and Pseudomonas aeruginosa were evaluated using micro-dilution assay and further antimicrobial activity of fabricated nanofibers was performed. Finally, in vivo studies were performed to demonstrate the wound-healing efficacy of composite nanofibers. In vitro results confirmed the potential antimicrobial efficacy provided by AgNPs and AgNPs composite nanofibers, essential to provide an aseptic environment at the wound site. In vivo study revealed that the rate of wound healing of the composite nanofiber mats was found to be accelerated compared with plain collagen nanofibers. Histology analysis revealed an accelerated re-epithelization, collagen production, and better wound contraction with AgNPs composite collagen nanofibers.
Mild Cognitive Impairment Is Characterized by Deficient Brainstem and Cortical Representations of Speech

Mild cognitive impairment (MCI) is recognized as a transitional phase in the progression toward more severe forms of dementia and is an early precursor to Alzheimer's disease. Previous neuroimaging studies reveal that MCI is associated with aberrant sensory–perceptual processing in cortical brain regions subserving auditory and language function. However, whether the pathophysiology of MCI extends to speech processing before conscious awareness (brainstem) is unknown. Using a novel electrophysiological approach, we recorded both brainstem and cortical speech-evoked brain event-related potentials (ERPs) in older, hearing-matched human listeners who did and did not present with subtle cognitive impairment revealed through behavioral neuropsychological testing. We found that MCI was associated with changes in neural speech processing characterized as hypersensitivity (larger) brainstem and cortical speech encoding in MCI compared with controls in the absence of any perceptual speech deficits. Group differences also interacted with age differentially across the auditory pathway; brainstem responses became larger and cortical ERPs smaller with advancing age. Multivariate classification revealed that dual brainstem–cortical speech activity correctly identified MCI listeners with 80% accuracy, suggesting its application as a biomarker of early cognitive decline. Brainstem responses were also a more robust predictor of individuals' MCI severity than cortical activity. Our findings suggest that MCI is associated with poorer encoding and transfer of speech signals between functional levels of the auditory system and advance the pathophysiological understanding of cognitive aging by identifying subcortical deficits in auditory sensory processing mere milliseconds (<10 ms) after sound onset and before the emergence of perceptual speech deficits. SIGNIFICANCE STATEMENT Mild cognitive impairment (MCI) is a precursor to dementia marked by declines in communication skills. Whether MCI pathophysiology extends below cerebral cortex to affect speech processing before conscious awareness (brainstem) is unknown. By recording neuroelectric brain activity to speech from brainstem and cortex, we show that MCI hypersensitizes the normal encoding of speech information across the hearing brain. Deficient neural responses to speech (particularly those generated from the brainstem) predicted the presence of MCI with high accuracy and before behavioral deficits. Our findings advance the neurological understanding of MCI by identifying a subcortical biomarker in auditory–sensory processing before conscious awareness, which may be a precursor to declines in speech understanding.
Inducible Activation of ERK5 MAP Kinase Enhances Adult Neurogenesis in the Olfactory Bulb and Improves Olfactory Function

Recent discoveries have suggested that adult neurogenesis in the subventricular zone (SVZ) and olfactory bulb (OB) may be required for at least some forms of olfactory behavior in mice. However, it is unclear whether conditional and selective enhancement of adult neurogenesis by genetic approaches is sufficient to improve olfactory function under physiological conditions or after injury. Furthermore, specific signaling mechanisms regulating adult neurogenesis in the SVZ/OB are not fully defined. We previously reported that ERK5, a MAP kinase selectively expressed in the neurogenic regions of the adult brain, plays a critical role in adult neurogenesis in the SVZ/OB. Using a site-specific knock-in mouse model, we report here that inducible and targeted activation of the endogenous ERK5 in adult neural stem/progenitor cells enhances adult neurogenesis in the OB by increasing cell survival and neuronal differentiation. This conditional ERK5 activation also improves short-term olfactory memory and odor-cued associative olfactory learning under normal physiological conditions. Furthermore, these mice show enhanced recovery of olfactory function and have more adult-born neurons after a zinc sulfate-induced lesion of the main olfactory epithelium. We conclude that ERK5 MAP kinase is an important endogenous signaling pathway regulating adult neurogenesis in the SVZ/OB, and that conditional activation of endogenous ERK5 is sufficient to enhance adult neurogenesis in the OB thereby improving olfactory function both under normal conditions and after injury.
Splenectomy or Partial Splenectomy should be Preferred Treatment for Large Splenic Hydatid Cysts

The article by Arce and others was helpful. However, in cases of giant splenic hydatid cyst, splenectomy or partial splenectomy is generally considered the preferred treatment rather than removal of the cyst, as reported by Rashid and others. If there is more than one cyst, a large cyst, a cyst in a deep organ location, or an infected cyst, open surgery should be done. I agree with Arce and others that the laparoscopic approach is the preferred treatment for splenic hydatid disease, but only in the case of a small cyst. Also, removal only of the cyst is not the recommended treatment in the literature for splenic hydatidosis, especially for large cysts. Similar recommendations have been made by Eris and others. I agree that preservation of the spleen whenever possible is justified because of its role in protecting against infection. But in the case of large hydatid cysts in an elderly patient, splenectomy or partial splenectomy should be preferred.
Redisplacement Rates after Reduction and Cast Immobilization of Isolated Distal Radial Fractures

Background The maintenance of satisfactory alignment in distal radial fractures following closed reduction and casting of the forearm is challenging. Redisplacement rates of between 2 and 91% have been described, mostly for Western populations and for fractures involving both the forearm bones. The local scenario is unexplored. Objective This study sought to determine the rate of redisplacement in isolated closed distal radial fractures in children aged 6-15 years and the factors contributing to the redisplacement. Setting The Kenyatta National Hospital, a teaching and referral hospital in Kenya. Patients and Methods This was a prospective study carried out between June 2005 and February2006. Patients were recruited from casualty, where the fracture was reduced and casted. Immediate check x-rays were taken to ascertain satisfactory alignment. At follow up the fractures were evaluated for redisplacement in the fracture clinic in the second and fourth weeks with further check x-rays. Redisplacement was regarded as the presence of dorsal or volar- angulation of greater than 200. The data was collected and entered into statistical package for social sciences (SPSS) 12.0 version. Comparison of the binomial outcomes of the factors determining the redisplacement of the distal radial fractures was carried out using Fischer’s exact test. P value <0.05 was taken to be significant. Results Ninety-two patients were evaluated. Overall redisplacement rate was 15.7%. Factors significantly associated with redisplacement included initial displacement, completeness of fracture and non-satisfactory initial reduction. Conclusion The rate of redisplacement of 15.7% reported here is within the range that is considered acceptable. The success of re-manipulation at the KNH is unsatisfactory. Percutaneous K-wiring should be considered for those with complete fractures with displacement that do not achieve perfect reduction at initial check radiographic film.
Alternations of Maternal and Cord Plasma Hemostasis in Preeclampsia Before and After Delivery

Objective: The aim of this study was to investigate the role of hemostatic factors in the pathogenesis of preeclampsia. Materials and Methods: Maternal and cord plasma concentrations of tissue factor (TF), tissue factor pathway inhibitor (TFPI), von willebrand factor (vWF), soluble P-selectin (sP-selectin), fibrinopeptide A (FPA), D-dimer, and antithrombin III (AT-III) were measured by enzyme-linked immunosorbent assay (ELISA) in 46 women with preeclampsia and 40 normotensive pregnant women before and after delivery. Results: The maternal plasma concentrations of TF, vWF, and sP‐selectin were higher, but lower concentrations of TFPI, AT-III, and D-dimer were observed in women with preeclampsia compared to normotensive pregnant women before and after delivery. Compared with maternal plasma, fetal plasma concentrations of TF concentrations were increased significantly in both groups, whereas vWF, FPA, TFPI, AT-III, and D-dimer were decreased. Compared with normotensive pregnancy, fetal plasma concentrations of TF were markedly increased in preeclampsia, accompanied with a higher vWF and a lower sP-selectin and D-dimer levels. Furthermore, fetal plasma TF concentrations were more significantly increased in women with high blood pressure and severe proteinuria. Conclusions: Imbalance in the coagulation/fibrinolysis equilibrium, especially alterations in the extrinsic pathway of coagulation and anticoagulation, may play an important role in the pathogenesis of preeclampsia. In addition, fetal alteration of TF may be involved in the pathogenesis of fetal complications of preeclampsia.
Targeting a Potassium Channel/Syntaxin Interaction Ameliorates Cell Death in Ischemic Stroke

The voltage-gated K+ channel Kv2.1 has been intimately linked with neuronal apoptosis. After ischemic, oxidative, or inflammatory insults, Kv2.1 mediates a pronounced, delayed enhancement of K+ efflux, generating an optimal intracellular environment for caspase and nuclease activity, key components of programmed cell death. This apoptosis-enabling mechanism is initiated via Zn2+-dependent dual phosphorylation of Kv2.1, increasing the interaction between the channel's intracellular C-terminus domain and the SNARE (soluble N-ethylmaleimide-sensitive factor activating protein receptor) protein syntaxin 1A. Subsequently, an upregulation of de novo channel insertion into the plasma membrane leads to the critical enhancement of K+ efflux in damaged neurons. Here, we investigated whether a strategy designed to interfere with the cell death-facilitating properties of Kv2.1, specifically its interaction with syntaxin 1A, could lead to neuroprotection following ischemic injury in vivo. The minimal syntaxin 1A-binding sequence of Kv2.1 C terminus (C1aB) was first identified via a far-Western peptide screen and used to create a protherapeutic product by conjugating C1aB to a cell-penetrating domain. The resulting peptide (TAT-C1aB) suppressed enhanced whole-cell K+ currents produced by a mutated form of Kv2.1 mimicking apoptosis in a mammalian expression system, and protected cortical neurons from slow excitotoxic injury in vitro, without influencing NMDA-induced intracellular calcium responses. Importantly, intraperitoneal administration of TAT-C1aB in mice following transient middle cerebral artery occlusion significantly reduced ischemic stroke damage and improved neurological outcome. These results provide strong evidence that targeting the proapoptotic function of Kv2.1 is an effective and highly promising neuroprotective strategy. SIGNIFICANCE STATEMENT Kv2.1 is a critical regulator of apoptosis in central neurons. It has not been determined, however, whether the cell death-enabling function of this K+ channel can be selectively targeted to improve neuronal survival following injury in vivo. The experiments presented here demonstrate that the cell death-specific role of Kv2.1 can be uniquely modulated to provide neuroprotection in an animal model of acute ischemic stroke. We thus reveal a novel therapeutic strategy for neurological disorders that are accompanied by Kv2.1-facilitated forms of cell death.
Top-Down Modulation of Lateral Interactions in Visual Cortex

The primary visual cortex (V1) changes its computation according to the perceptual task being performed. We propose that this cognitive modulation results from gating of V1 intrinsic connections. To test this idea, using behavioral paradigms that engage top-down modulation of V1 contextual interactions, we recorded from chronically implanted electrode arrays in macaques. We observed task-dependent changes in interactions between V1 sites measured both by correlation between spike trains and by coherence between local field potentials (LFP-LFP coherence). The direction of the changes in aggregate activity, as measured by LFPs, depended on perceptual strategy: perceptual grouping increased LFP coherence between sites crucial for the task, whereas perceptual segregation lowered the LFP coherence. Using spiking activity as a measure, we found that the behaviorally driven changes in correlation structure between neurons dramatically increased the stimulus-related information that they convey; this additional increase in encoded information at the level of neuronal ensembles equals that obtained from task-driven reconfigurations of neural tuning curves. The improvements in information encoding were strongest for stimuli with greatest discrimination difficulty.
Preeclampsia, Placenta, Oxidative Stress, and PMCA

Objective: The aim of this study is to summarize the reported evidence on the possible relationship between preeclampsia, placenta, oxidative stress and plasma membrane Ca-ATPase (PMCA) activity, responsible for fine control of intracellular calcium concentration. Methods: Literature search was conducted in MEDLINE/PubMed and several unpublished results from our laboratory were included. Results: Lipid peroxidation in placental and red blood cell plasma membranes during preeclampsia and a concomitant diminution of their PMCA activity are described. Conclusions: Uteroplacental hypoperfusion raises lipid peroxidation by-products in the blood plasma that could alter structure and functionality of the cell membranes of the endothelium and several tissues.
Blood Pressure Regulation by the Rostral Ventrolateral Medulla in Conscious Rats: Effects of Hypoxia, Hypercapnia, Baroreceptor Denervation, and Anesthesia

Current understanding of the contribution of C1 neurons to blood pressure (BP) regulation derives predominantly from experiments performed in anesthetized animals or reduced ex vivo preparations. Here, we use ArchaerhodopsinT3.0 (ArchT) loss-of-function optogenetics to explore BP regulation by C1 neurons in intact, unanesthetized rats. Using a lentivirus that expresses ArchT under the Phox2b-activated promoter PRSx8 (PRSx8-ArchT), ∼65% of transduced neurons were C1 (balance retrotrapezoid nucleus, RTN). Other rats received CaMKII-ArchT3.0 AAV2 (CaMKII-ArchT), which transduced C1 neurons and larger numbers of unidentified glutamatergic and GABAergic cells. Under anesthesia, ArchT photoactivation reduced sympathetic nerve activity and BP and silenced/strongly inhibited most (7/12) putative C1 neurons. In unanesthetized PRSx8-ArchT-treated rats breathing room air, bilateral ArchT photoactivation caused a very small BP reduction that was only slightly larger under hypercapnia (6% FiCO2), but was greatly enhanced during hypoxia (10 and 12% FiO2), after sino-aortic denervation, or during isoflurane anesthesia. The degree of hypotension correlated with percentage of ArchT-transduced C1 neurons. ArchT photoactivation produced similar BP changes in CaMKII-ArchT-treated rats. Photoactivation in PRSX8-ArchT rats reduced breathing frequency (FR), whereas FR increased in CaMKII-ArchT rats. We conclude that the BP drop elicited by ArchT activation resulted from C1 neuron inhibition and was unrelated to breathing changes. C1 neurons have low activity under normoxia, but their activation is important to BP stability during hypoxia or anesthesia and contributes greatly to the hypertension caused by baroreceptor deafferentation. Finally, C1 neurons are marginally activated by hypercapnia and the large breathing stimulation caused by this stimulus has very little impact on resting BP. SIGNIFICANCE STATEMENT C1 neurons are glutamatergic/peptidergic/catecholaminergic neurons located in the medulla oblongata, which may operate as a switchboard for differential, behavior-appropriate activation of selected sympathetic efferents. Based largely on experimentation in anesthetized or reduced preparations, a rostrally located subset of C1 neurons may contribute to both BP stabilization and dysregulation (hypertension). Here, we used Archaerhodopsin-based loss-of-function optogenetics to explore the contribution of these neurons to BP in conscious rats. The results suggest that C1 neurons contribute little to resting BP under normoxia or hypercapnia, C1 neuron discharge is restrained continuously by arterial baroreceptors, and C1 neuron activation is critical to stabilize BP under hypoxia or anesthesia. This optogenetic approach could also be useful to explore the role of C1 neurons during specific behaviors or in hypertensive models.
Hepatic disease in Alberta horses: A retrospective study of 'alsike clover poisoning' (1973-1988).

Over sixteen years, 49 horses were diagnosed by Alberta Agriculture Animal Health laboratories as having “alsike clover poisoning”. There was a distinct northwestern distribution of cases, the majority coming from the Peace River district. This distribution is opposite to that of the Alberta horse population, but coincides with areas of alsike clover cultivation. Cases could be divided into chronic or nervous clinical presentations, as described by Schofield. Tissues from 45 animals were retrieved and examined microscopically. Significant histological lesions were confined to the liver and consisted of biliary fibrosis and epithelial proliferation. I conclude that alsike clover poisoning is a specific disease entity, likely due to exposure to an exogenous toxin. The evidence is not strong enough to incriminate alsike clover as the etiology.
Cardiovascular variability before and after delivery: recovery from arterial stiffness in women with preeclampsia 4 days post partum

Objective: We studied the short-term response of autonomic control to delivery in normal pregnancies and pregnancies with preeclampsia (PE). Methods: Fourteen healthy pregnant women and 13 women with PE were monitored within four days before and four days after delivery and compared to values of 14 non-pregnant women as controls using high-resolution electrocardiogram and noninvasive continuous blood pressure monitoring. Results: In PE, blood pressure remained elevated four days postpartum, but markers for arterial stiffness normalized. In contrast, none of heart rate variability and baroreflex sensitivity parameters, altered due to either pregnancy or disease, were normalized 96 h after delivery. Conclusion: Four days after delivery, the maternal cardiovascular system is still strongly affected by pregnancy independent of the health status.
Effect of Korean Red Ginseng Supplementation on Ocular Blood Flow in Patients with Glaucoma

The purpose of this study was to evaluate the effect of Korean red ginseng (KRG) on ocular blood flow in patients with glaucoma. In a prospective, randomized, placebo-controlled, double-masked crossover trial, 36 patients with open-angle glaucoma were consecutively recruited. Subjects were randomly assigned into two groups. Group A received 1.5 g KRG, administered orally three times daily for 12 weeks, followed by a wash-out period of 8 weeks and 12 weeks of placebo treatment (identical capsules filled with 1.5 g corn starch). Group B underwent the same regimen, but took the placebo first and then KRG. Blood pressure, heart rate, and intraocular pressure were measured at baseline and at the end of each phase of the study. Visual field examination and ocular blood flow measurements by the Heidelberg Retina Flowmeter were performed at baseline and at the end of each phase of the study. Changes in blood pressure, heart rate, intraocular pressure, visual field indices, and retinal peripapillary blood flow were evaluated. Blood pressure, heart rate, intraocular pressure, and visual field indices did not change after placebo or KRG treatment. After KRG treatment, retinal peripapillary blood flow in the temporal peripapillary region significantly improved (p = 0.005). No significant changes were found in retinal peripapillary blood flow in either the rim region or the nasal peripapillary region (p = 0.051 and 0.278, respectively). KRG ingestion appears to improve retinal peripapillary blood flow in patients with open-angle glaucoma. These results imply that KRG ingestion might be helpful for glaucoma management.
External validation of a model for periconceptional prediction of recurrent early-onset preeclampsia

Objective: To validate a previously published prediction model for recurrent early-onset preeclampsia (PE). Methods: We included 229 pregnant women with a history of early-onset PE and computed their risk using the prediction model, compared the predicted risk to their pregnancy outcomes and assessed performance of the model. Results: Early-onset PE recurred in 6.6% of participants. The area under the receiver operating characteristic curve was 59% (95% CI: 45–73). The model created groups that were only moderately different in terms of their risk. Conclusions: The model’s discriminate ability was poor and predictive performance insufficient to classify women into relevant risk groups.