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CMAJ : Canadian Medical Association... Jun 2024
Topics: Humans; Male; Alopecia; Child; Tinea; Scalp; Antifungal Agents; Scalp Dermatoses
PubMed: 38830674
DOI: 10.1503/cmaj.231613-f -
Journal of Family Medicine and Primary... Apr 2024
PubMed: 38827723
DOI: 10.4103/jfmpc.jfmpc_1665_23 -
Cognitive Neurodynamics Jun 2024Mental subtraction, involving numerical processing and operation, requires a complex interplay among several brain regions. Diverse studies have utilized scalp...
UNLABELLED
Mental subtraction, involving numerical processing and operation, requires a complex interplay among several brain regions. Diverse studies have utilized scalp electroencephalograph, electrocorticogram, or functional magnetic resonance imaging to resolve the structure pattern and functional activity during subtraction operation. However, a high resolution of the spatial-temporal understanding of the neural mechanisms involved in mental subtraction is unavailable. Thus, this study obtained intracranial stereoelectroencephalography recordings from 20 patients with pharmacologically resistant epilepsy. Specifically, two sample-delayed mismatch paradigms of numeric comparison and subtracting results comparison were used to help reveal the time frame of mental subtraction. The brain sub-regions were chronologically screened using the stereoelectroencephalography recording for mental subtraction. The results indicated that the anterior cortex, containing the frontal, insular, and parahippocampous, worked for preparing for mental subtraction; moreover, the posterior cortex, such as parietal, occipital, limbic, and temporal regions, cooperated during subtraction. Especially, the gamma band activities in core regions within the parietal-cingulate-temporal cortices mediated the critical mental subtraction. Overall, this research is the first to describe the spatiotemporal activities underlying mental subtraction in the human brain. It provides a comprehensive insight into the cognitive control activity underlying mental arithmetic.
SUPPLEMENTARY INFORMATION
The online version contains supplementary material available at 10.1007/s11571-023-09937-z.
PubMed: 38826664
DOI: 10.1007/s11571-023-09937-z -
BioRxiv : the Preprint Server For... May 2024Experience changes the tuning of sensory neurons, including neurons in retinotopic visual cortex, as evident from work in humans and non-human animals. In human...
Experience changes the tuning of sensory neurons, including neurons in retinotopic visual cortex, as evident from work in humans and non-human animals. In human observers, visuo-cortical re-tuning has been studied during aversive generalization learning paradigms, in which the similarity of generalization stimuli (GSs) with a conditioned threat cue (CS+) is used to quantify tuning functions. This work utilized pre-defined tuning shapes reflecting prototypical generalization (Gaussian) and sharpening (Difference-of-Gaussians) patterns. This approach may constrain the ways in which re-tuning can be characterized, for example if tuning patterns do not match the prototypical functions or represent a mixture of functions. The present study proposes a flexible and data-driven method for precisely quantifying changes in neural tuning based on the Ricker wavelet function and the Bayesian bootstrap. The method is illustrated using data from a study in which university students (n = 31) performed an aversive generalization learning task. Oriented gray-scale gratings served as CS+ and GSs and a white noise served as the unconditioned stimulus (US). Acquisition and extinction of the aversive contingencies were examined, while steady-state visual event potentials (ssVEP) and alpha-band (8-13 Hz) power were measured from scalp EEG. Results showed that the Ricker wavelet model fitted the ssVEP and alpha-band data well. The pattern of re-tuning in ssVEP amplitude across the stimulus gradient resembled a generalization (Gaussian) shape in acquisition and a sharpening (Difference-of-Gaussian) shape in an extinction phase. As expected, the pattern of re-tuning in alpha-power took the form of a generalization shape in both phases. The Ricker-based approach led to greater Bayes factors and more interpretable results compared to prototypical tuning models. The results highlight the promise of the current method for capturing the precise nature of visuo-cortical tuning functions, unconstrained by the exact implementation of prototypical a-priori models.
PubMed: 38826264
DOI: 10.1101/2024.05.22.595429 -
The Nigerian Postgraduate Medical... Apr 2024This study reviewed the current knowledge on the epidemiology, pathophysiology, clinical presentations, diagnosis, treatment, quality-of-life assessment and recent... (Review)
Review
This study reviewed the current knowledge on the epidemiology, pathophysiology, clinical presentations, diagnosis, treatment, quality-of-life assessment and recent trends in androgenetic alopecia (AGA). Relevant articles on AGA from PubMed, Google Scholar, Medline and Scopus from 1950 to 2024 were obtained and scrutinized.. Key search words included each term like 'androgenetic alopecia', 'androgenic alopecia', 'pattern baldness' and 'pattern hair loss' AND each term like 'epidemiology', 'pathophysiology', 'genetics', 'hormones', 'micronutrient', 'stress and inflammation', 'growth factors', 'clinical features', 'staging', 'cardiovascular associations', 'diagnosis' and 'management' were used in the search. AGA is a non-scarring hair loss that is exemplified by a progressive decline of hair follicles, or non-functional or dead hair follicles in the scalp in a defined pattern. It is the most common hair loss, more common in men but can also present in younger age as premature AGA. Hormones, genetics, micronutrient deficiency, microinflammation and stress have been implicated, while psychosocial distress and cutaneous correlate of cardiovascular diseases have become sources of relentless research. AGA is a patterned hair loss that is more prevalent in Men. It results from the interactions between hormonal, genetic and other factors which determine the extent of hair loss and associated disorders (psychosocial and cardiovascular). As results of more research become available, the extent of AGA, its comorbidities as well as the full spectrum of their manifestations will continue to be sources of health education and more holistic examination by dermatologists and patients.
Topics: Humans; Alopecia; Quality of Life; Male; Female
PubMed: 38826011
DOI: 10.4103/npmj.npmj_47_24 -
Journal of Oleo Science 2024Hair is important to our appearance as well as to protect our heads. Human hair mainly consists of proteins (80-85%), melanin pigments (0-5%), water (10-13%), and lipids... (Review)
Review
Hair is important to our appearance as well as to protect our heads. Human hair mainly consists of proteins (80-85%), melanin pigments (0-5%), water (10-13%), and lipids (1-6%). The physicochemical properties of hair have been studied for over 100 years. However, they are not yet thoroughly understood. In this review, recent progress and the latest findings are summarized from the following three perspectives: structural characteristics, delivery and distribution of active ingredients, and hair as a template. The structural characteristics of hair have been mainly investigated by microscopic and/or spectroscopic techniques such as atomic force microscopy integrated with infrared spectroscopy (AFM-IR) and rheological measurements. The distribution of active ingredients has been generally evaluated through techniques such as nanoscale secondary ion mass spectrometry (NanoSIMS). And finally, attempts to explore the potential of hair to be used as a substrate for flexible device fabrication will be introduced.
Topics: Hair; Humans; Microscopy, Atomic Force; Melanins; Chemical Phenomena; Spectrometry, Mass, Secondary Ion; Rheology; Spectrophotometry, Infrared; Lipids; Water; Proteins
PubMed: 38825536
DOI: 10.5650/jos.ess23203 -
Dermatology and Therapy Jun 2024Recent advancements in androgenetic alopecia (AGA) treatment have highlighted the efficacy of botulinum toxin (BoNT). However, inconsistencies in injection sites and...
INTRODUCTION
Recent advancements in androgenetic alopecia (AGA) treatment have highlighted the efficacy of botulinum toxin (BoNT). However, inconsistencies in injection sites and depths warrant attention. It remains unclear which injection strategy is most beneficial for patients.
METHODS
This split-scalp randomized controlled trial divided each enrolled participant's scalp along the midline: one side was randomized to receive intramuscular BoNT injections in the surrounding muscles, while the other side received intradermal BoNT injections directly into the balding areas. This study evaluated the impact of treatment on hair density and diameter through trichoscopic examinations conducted at baseline and 12 weeks post treatment. Additionally, assessments of pain and overall safety were integrated into the study protocol.
RESULTS
Twenty-nine patients completed the study, with significant improvements in hair density observed in the intramuscular injection group compared to the intradermal group (p < 0.001). Both groups exhibited increases in hair diameter, but no significant difference was found between the two methods (p = 0.433). Pain evaluation revealed that intradermal injections in balding areas were more painful than intramuscular injections (p = 0.036), with no severe adverse reactions reported except for a single case of alopecia areata following injection.
CONCLUSION
Our research revealed that both BoNT injection strategies enhanced hair diameter 12 weeks post-treatment, with intramuscular injections significantly improving hair density more effectively. Despite the promising outcomes, the variability in patient responses underscores the necessity for personalized approaches and further research to refine injection protocols for optimized efficacy and safety.
TRIAL REGISTRATION NUMBER
ChiCTR2400080190.
PubMed: 38824483
DOI: 10.1007/s13555-024-01189-x -
Asian Journal of Surgery Jun 2024
PubMed: 38824019
DOI: 10.1016/j.asjsur.2024.05.122 -
Brain Stimulation 2024Transcranial magnetic stimulation (TMS) is believed to alter ongoing neural activity and cause circuit-level changes in brain function. While the electrophysiological...
BACKGROUND
Transcranial magnetic stimulation (TMS) is believed to alter ongoing neural activity and cause circuit-level changes in brain function. While the electrophysiological effects of TMS have been extensively studied with scalp electroencephalography (EEG), this approach generally evaluates low-frequency neural activity at the cortical surface. However, TMS can be safely used in patients with intracranial electrodes (iEEG), allowing for direct assessment of deeper and more localized oscillatory responses across the frequency spectrum.
OBJECTIVE/HYPOTHESIS
Our study used iEEG to understand the effects of TMS on human neural activity in the spectral domain. We asked (1) which brain regions respond to cortically-targeted TMS, and in what frequency bands, (2) whether deeper brain structures exhibit oscillatory responses, and (3) whether the neural responses to TMS reflect evoked versus induced oscillations.
METHODS
We recruited 17 neurosurgical patients with indwelling electrodes and recorded neural activity while patients underwent repeated trials of single-pulse TMS at either the dorsolateral prefrontal cortex (DLPFC) or parietal cortex. iEEG signals were analyzed using spectral methods to understand the oscillatory responses to TMS.
RESULTS
Stimulation to DLPFC drove widespread low-frequency increases (3-8 Hz) in frontolimbic cortices and high-frequency decreases (30-110 Hz) in frontotemporal areas, including the hippocampus. Stimulation to parietal cortex specifically provoked low-frequency responses in the medial temporal lobe. While most low-frequency activity was consistent with phase-locked evoked responses, anterior frontal regions exhibited induced theta oscillations following DLPFC stimulation.
CONCLUSIONS
By combining TMS with intracranial EEG recordings, our results suggest that TMS is an effective means to perturb oscillatory neural activity in brain-wide networks, including deeper structures not directly accessed by stimulation itself.
Topics: Humans; Transcranial Magnetic Stimulation; Male; Adult; Female; Middle Aged; Electroencephalography; Electrocorticography; Parietal Lobe; Young Adult; Dorsolateral Prefrontal Cortex; Brain Waves
PubMed: 38821396
DOI: 10.1016/j.brs.2024.05.014 -
Photodiagnosis and Photodynamic Therapy May 2024Dissecting cellulitis of the scalp (DCS) has a significant impact on the physical well-being and body image of the patient. Since DCS often responds poorly to...
Effectiveness of 5-aminolevulinic acid photodynamic therapy in treating dissecting cellulitis of the scalp and pathological changes in skin lesions: A retrospective study.
BACKGROUND
Dissecting cellulitis of the scalp (DCS) has a significant impact on the physical well-being and body image of the patient. Since DCS often responds poorly to conventional treatments, there is a need to identify alternative treatment strategies. This study aimed to explore the effectiveness of 5-aminolevulinic acid photodynamic therapy (ALA-PDT) in treating DCS.
METHODS
Twelve male patients with DCS treated solely with ALA-PDT between June 2022 and June 2023 at our institution were enrolled in this study. Two patients underwent a biopsy before and after treatment for comparison. The efficacy of the treatments was assessed 10 days after treatment by evaluating the symptom scores recorded on medical records and by assessing the photographs acquired before and after treatment. In addition, the impact of the treatment on pain relief and median recurrence rate were also extracted.
RESULTS
Out of the 12 enrolled patients, the majority of the patients (75%) had a significant reduction in the nodules or abscesses. The pain relief was significant in 3 patients (25%), and moderate in 7 patients (58.3%). For the subcutaneous sinus tract symptoms, 3 patients (27.3%) showed moderate improvement, and 7 (63.6%) had a mild improvement. Six patients (75%) had mild improvement in their alopecia. The pathology results showed a decrease in the number of lymphocytes, macrophages, and neutrophils within the skin lesions following the administration of ALA-PDT.
CONCLUSION
ALA-PDT can effectively reduce the DCS symptoms and the number of lymphocytes, macrophages, and neutrophils within the skin lesions.
PubMed: 38821237
DOI: 10.1016/j.pdpdt.2024.104227