"Denervation supersensitivity" of serotonin (5-HT) receptors has been proposed to explain the behavioral supersensitivity to 5-hydroxytryptophan (5-HTP) which develops after lesions of indoleamine neurons with 5,7-dihydroxytryptamine (5,7-DHT). To examine the possible role of receptor recognition sites and second messenger activity in supersensitivity, we measured regional 5-HT2 receptor ligand binding and 5-HT-stimulated phosphoinositide turnover in adult rats with 5,7-DHT lesions made by intracisternal injection and their saline-treated controls. In [3H]ketanserin binding studies of fresh brain tissue two weeks after 5,7-DHT injection, there were no significant changes in frontal cortex, brainstem, or spinal cord in Bmax, Kd, or nH of 5-HT2 receptors, 5,7-DHT lesions did not affect basal levels of [3H]inositol phosphate (IP) accumulation but significantly increased 5-HT-stimulated [3H]IP accumulation in the brainstem (+27%) and cortex (+23%). Because brainstem rather than cortex is involved in 5-HTP-evoked myoclonus, increased 5-HT-stimulated phosphoinositide hydrolysis in brainstem following 5,7-DHT lesions in the rat may be relevant to serotonergic behavioral supersensitivity.
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http://dx.doi.org/10.1016/0361-9230(90)90296-c | DOI Listing |
Jpn J Radiol
January 2025
Department of Radiology, Ehime University Graduate School of Medicine, Shitsukawa, Toon, Ehime, 791-0295, Japan.
Purpose: To evaluate the effects of four-dimensional noise reduction filtering using a similarity algorithm (4D-SF) on the image quality and tumor visibility of low-dose dynamic computed tomography (CT) in evaluating breast cancer.
Materials And Methods: Thirty-four patients with 38 lesions who underwent low-dose dynamic breast CT and were pathologically diagnosed with breast cancer were enrolled. Dynamic CT images were reconstructed using iterative reconstruction alone or in combination with 4D-SF.
J Neurol
January 2025
Department of Neurology, University of Chicago, 5841 South Maryland Avenue, Chicago, IL, 60637, USA.
Positional downbeat nystagmus (pDBN) is a common finding in dizzy patients, with etiologies ranging from benign paroxysmal positional vertigo (BPPV) to central vestibular lesions. Although peripheral pDBN often presents with distinct clinical features that differentiate it from BPPV, diagnosing its etiology can be challenging. A thorough clinical evaluation, including the physical characteristics of the nystagmus, response to positional maneuvers, and neurological findings, is often sufficient to diagnose conditions that provoke pDBN such as anterior canal BPPV, atypical posterior canal BPPV, and central causes.
View Article and Find Full Text PDFFEMS Microbiol Ecol
January 2025
NIAB East Malling, New Road, Kent, ME19 6BJ, UK.
Severity of European apple canker caused by Neonectria ditissima can vary between locations and apple genotypes. We investigated how location, cold storage/planting season, and apple scion genotype affect root-associated microbial communities. Additionally, we investigated whether differences in abundance of specific taxa could be associated with canker lesion counts.
View Article and Find Full Text PDFAcad Radiol
January 2025
Department of Hepatobiliary and Pancreatic Surgery, The Affiliated Cancer Hospital of Zhengzhou University & Henan Cancer Hospital, Zhengzhou, Henan, China (Q.L., J.O., Y.Z., J.Z.). Electronic address:
Rationale And Objectives: The purpose of this study was to demonstrate the impact of postoperative adjuvant transarterial chemoembolization (TACE) on the prognosis of patients with macrotrabecular-massive hepatocellular carcinoma (MTM-HCC).
Materials And Methods: This retrospective study used the clinical records of patients with resected MTM-HCC with/without adjuvant TACE at three centers between January 2015 and December 2022. The primary end point was recurrence free survival (RFS).
BMJ Case Rep
January 2025
Obstetrics and Gynecology, All India Institute of Medical Sciences, New Delhi, Delhi, India.
Malignant peripheral nerve sheath tumours (MPNSTs) are aggressive sarcomas that occur rarely in the cervix. Considering the varied clinical features and the absence of a pathognomonic immunohistochemical marker, it is always challenging to diagnose these tumours. Treatment has not been standardised as yet, but a combination of surgery, radiotherapy and chemotherapy is used to treat MPNSTs of the cervix.
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